xref: /linux/security/selinux/hooks.c (revision 8883957b3c9de2087fb6cf9691c1188cccf1ac9c)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Security-Enhanced Linux (SELinux) security module
4  *
5  *  This file contains the SELinux hook function implementations.
6  *
7  *  Authors:  Stephen Smalley, <stephen.smalley.work@gmail.com>
8  *	      Chris Vance, <cvance@nai.com>
9  *	      Wayne Salamon, <wsalamon@nai.com>
10  *	      James Morris <jmorris@redhat.com>
11  *
12  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
13  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
14  *					   Eric Paris <eparis@redhat.com>
15  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
16  *			    <dgoeddel@trustedcs.com>
17  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
18  *	Paul Moore <paul@paul-moore.com>
19  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
20  *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
21  *  Copyright (C) 2016 Mellanox Technologies
22  */
23 
24 #include <linux/init.h>
25 #include <linux/kd.h>
26 #include <linux/kernel.h>
27 #include <linux/kernel_read_file.h>
28 #include <linux/errno.h>
29 #include <linux/sched/signal.h>
30 #include <linux/sched/task.h>
31 #include <linux/lsm_hooks.h>
32 #include <linux/xattr.h>
33 #include <linux/capability.h>
34 #include <linux/unistd.h>
35 #include <linux/mm.h>
36 #include <linux/mman.h>
37 #include <linux/slab.h>
38 #include <linux/pagemap.h>
39 #include <linux/proc_fs.h>
40 #include <linux/swap.h>
41 #include <linux/spinlock.h>
42 #include <linux/syscalls.h>
43 #include <linux/dcache.h>
44 #include <linux/file.h>
45 #include <linux/fdtable.h>
46 #include <linux/namei.h>
47 #include <linux/mount.h>
48 #include <linux/fs_context.h>
49 #include <linux/fs_parser.h>
50 #include <linux/netfilter_ipv4.h>
51 #include <linux/netfilter_ipv6.h>
52 #include <linux/tty.h>
53 #include <net/icmp.h>
54 #include <net/ip.h>		/* for local_port_range[] */
55 #include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
56 #include <net/inet_connection_sock.h>
57 #include <net/net_namespace.h>
58 #include <net/netlabel.h>
59 #include <linux/uaccess.h>
60 #include <asm/ioctls.h>
61 #include <linux/atomic.h>
62 #include <linux/bitops.h>
63 #include <linux/interrupt.h>
64 #include <linux/netdevice.h>	/* for network interface checks */
65 #include <net/netlink.h>
66 #include <linux/tcp.h>
67 #include <linux/udp.h>
68 #include <linux/dccp.h>
69 #include <linux/sctp.h>
70 #include <net/sctp/structs.h>
71 #include <linux/quota.h>
72 #include <linux/un.h>		/* for Unix socket types */
73 #include <net/af_unix.h>	/* for Unix socket types */
74 #include <linux/parser.h>
75 #include <linux/nfs_mount.h>
76 #include <net/ipv6.h>
77 #include <linux/hugetlb.h>
78 #include <linux/personality.h>
79 #include <linux/audit.h>
80 #include <linux/string.h>
81 #include <linux/mutex.h>
82 #include <linux/posix-timers.h>
83 #include <linux/syslog.h>
84 #include <linux/user_namespace.h>
85 #include <linux/export.h>
86 #include <linux/msg.h>
87 #include <linux/shm.h>
88 #include <uapi/linux/shm.h>
89 #include <linux/bpf.h>
90 #include <linux/kernfs.h>
91 #include <linux/stringhash.h>	/* for hashlen_string() */
92 #include <uapi/linux/mount.h>
93 #include <linux/fsnotify.h>
94 #include <linux/fanotify.h>
95 #include <linux/io_uring/cmd.h>
96 #include <uapi/linux/lsm.h>
97 
98 #include "avc.h"
99 #include "objsec.h"
100 #include "netif.h"
101 #include "netnode.h"
102 #include "netport.h"
103 #include "ibpkey.h"
104 #include "xfrm.h"
105 #include "netlabel.h"
106 #include "audit.h"
107 #include "avc_ss.h"
108 
109 #define SELINUX_INODE_INIT_XATTRS 1
110 
111 struct selinux_state selinux_state;
112 
113 /* SECMARK reference count */
114 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
115 
116 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
117 static int selinux_enforcing_boot __initdata;
118 
enforcing_setup(char * str)119 static int __init enforcing_setup(char *str)
120 {
121 	unsigned long enforcing;
122 	if (!kstrtoul(str, 0, &enforcing))
123 		selinux_enforcing_boot = enforcing ? 1 : 0;
124 	return 1;
125 }
126 __setup("enforcing=", enforcing_setup);
127 #else
128 #define selinux_enforcing_boot 1
129 #endif
130 
131 int selinux_enabled_boot __initdata = 1;
132 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
selinux_enabled_setup(char * str)133 static int __init selinux_enabled_setup(char *str)
134 {
135 	unsigned long enabled;
136 	if (!kstrtoul(str, 0, &enabled))
137 		selinux_enabled_boot = enabled ? 1 : 0;
138 	return 1;
139 }
140 __setup("selinux=", selinux_enabled_setup);
141 #endif
142 
checkreqprot_setup(char * str)143 static int __init checkreqprot_setup(char *str)
144 {
145 	unsigned long checkreqprot;
146 
147 	if (!kstrtoul(str, 0, &checkreqprot)) {
148 		if (checkreqprot)
149 			pr_err("SELinux: checkreqprot set to 1 via kernel parameter.  This is no longer supported.\n");
150 	}
151 	return 1;
152 }
153 __setup("checkreqprot=", checkreqprot_setup);
154 
155 /**
156  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
157  *
158  * Description:
159  * This function checks the SECMARK reference counter to see if any SECMARK
160  * targets are currently configured, if the reference counter is greater than
161  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
162  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
163  * policy capability is enabled, SECMARK is always considered enabled.
164  *
165  */
selinux_secmark_enabled(void)166 static int selinux_secmark_enabled(void)
167 {
168 	return (selinux_policycap_alwaysnetwork() ||
169 		atomic_read(&selinux_secmark_refcount));
170 }
171 
172 /**
173  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
174  *
175  * Description:
176  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
177  * (1) if any are enabled or false (0) if neither are enabled.  If the
178  * always_check_network policy capability is enabled, peer labeling
179  * is always considered enabled.
180  *
181  */
selinux_peerlbl_enabled(void)182 static int selinux_peerlbl_enabled(void)
183 {
184 	return (selinux_policycap_alwaysnetwork() ||
185 		netlbl_enabled() || selinux_xfrm_enabled());
186 }
187 
selinux_netcache_avc_callback(u32 event)188 static int selinux_netcache_avc_callback(u32 event)
189 {
190 	if (event == AVC_CALLBACK_RESET) {
191 		sel_netif_flush();
192 		sel_netnode_flush();
193 		sel_netport_flush();
194 		synchronize_net();
195 	}
196 	return 0;
197 }
198 
selinux_lsm_notifier_avc_callback(u32 event)199 static int selinux_lsm_notifier_avc_callback(u32 event)
200 {
201 	if (event == AVC_CALLBACK_RESET) {
202 		sel_ib_pkey_flush();
203 		call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
204 	}
205 
206 	return 0;
207 }
208 
209 /*
210  * initialise the security for the init task
211  */
cred_init_security(void)212 static void cred_init_security(void)
213 {
214 	struct task_security_struct *tsec;
215 
216 	tsec = selinux_cred(unrcu_pointer(current->real_cred));
217 	tsec->osid = tsec->sid = SECINITSID_KERNEL;
218 }
219 
220 /*
221  * get the security ID of a set of credentials
222  */
cred_sid(const struct cred * cred)223 static inline u32 cred_sid(const struct cred *cred)
224 {
225 	const struct task_security_struct *tsec;
226 
227 	tsec = selinux_cred(cred);
228 	return tsec->sid;
229 }
230 
__ad_net_init(struct common_audit_data * ad,struct lsm_network_audit * net,int ifindex,struct sock * sk,u16 family)231 static void __ad_net_init(struct common_audit_data *ad,
232 			  struct lsm_network_audit *net,
233 			  int ifindex, struct sock *sk, u16 family)
234 {
235 	ad->type = LSM_AUDIT_DATA_NET;
236 	ad->u.net = net;
237 	net->netif = ifindex;
238 	net->sk = sk;
239 	net->family = family;
240 }
241 
ad_net_init_from_sk(struct common_audit_data * ad,struct lsm_network_audit * net,struct sock * sk)242 static void ad_net_init_from_sk(struct common_audit_data *ad,
243 				struct lsm_network_audit *net,
244 				struct sock *sk)
245 {
246 	__ad_net_init(ad, net, 0, sk, 0);
247 }
248 
ad_net_init_from_iif(struct common_audit_data * ad,struct lsm_network_audit * net,int ifindex,u16 family)249 static void ad_net_init_from_iif(struct common_audit_data *ad,
250 				 struct lsm_network_audit *net,
251 				 int ifindex, u16 family)
252 {
253 	__ad_net_init(ad, net, ifindex, NULL, family);
254 }
255 
256 /*
257  * get the objective security ID of a task
258  */
task_sid_obj(const struct task_struct * task)259 static inline u32 task_sid_obj(const struct task_struct *task)
260 {
261 	u32 sid;
262 
263 	rcu_read_lock();
264 	sid = cred_sid(__task_cred(task));
265 	rcu_read_unlock();
266 	return sid;
267 }
268 
269 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
270 
271 /*
272  * Try reloading inode security labels that have been marked as invalid.  The
273  * @may_sleep parameter indicates when sleeping and thus reloading labels is
274  * allowed; when set to false, returns -ECHILD when the label is
275  * invalid.  The @dentry parameter should be set to a dentry of the inode.
276  */
__inode_security_revalidate(struct inode * inode,struct dentry * dentry,bool may_sleep)277 static int __inode_security_revalidate(struct inode *inode,
278 				       struct dentry *dentry,
279 				       bool may_sleep)
280 {
281 	struct inode_security_struct *isec = selinux_inode(inode);
282 
283 	might_sleep_if(may_sleep);
284 
285 	/*
286 	 * The check of isec->initialized below is racy but
287 	 * inode_doinit_with_dentry() will recheck with
288 	 * isec->lock held.
289 	 */
290 	if (selinux_initialized() &&
291 	    data_race(isec->initialized != LABEL_INITIALIZED)) {
292 		if (!may_sleep)
293 			return -ECHILD;
294 
295 		/*
296 		 * Try reloading the inode security label.  This will fail if
297 		 * @opt_dentry is NULL and no dentry for this inode can be
298 		 * found; in that case, continue using the old label.
299 		 */
300 		inode_doinit_with_dentry(inode, dentry);
301 	}
302 	return 0;
303 }
304 
inode_security_novalidate(struct inode * inode)305 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
306 {
307 	return selinux_inode(inode);
308 }
309 
inode_security_rcu(struct inode * inode,bool rcu)310 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
311 {
312 	int error;
313 
314 	error = __inode_security_revalidate(inode, NULL, !rcu);
315 	if (error)
316 		return ERR_PTR(error);
317 	return selinux_inode(inode);
318 }
319 
320 /*
321  * Get the security label of an inode.
322  */
inode_security(struct inode * inode)323 static struct inode_security_struct *inode_security(struct inode *inode)
324 {
325 	__inode_security_revalidate(inode, NULL, true);
326 	return selinux_inode(inode);
327 }
328 
backing_inode_security_novalidate(struct dentry * dentry)329 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
330 {
331 	struct inode *inode = d_backing_inode(dentry);
332 
333 	return selinux_inode(inode);
334 }
335 
336 /*
337  * Get the security label of a dentry's backing inode.
338  */
backing_inode_security(struct dentry * dentry)339 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
340 {
341 	struct inode *inode = d_backing_inode(dentry);
342 
343 	__inode_security_revalidate(inode, dentry, true);
344 	return selinux_inode(inode);
345 }
346 
inode_free_security(struct inode * inode)347 static void inode_free_security(struct inode *inode)
348 {
349 	struct inode_security_struct *isec = selinux_inode(inode);
350 	struct superblock_security_struct *sbsec;
351 
352 	if (!isec)
353 		return;
354 	sbsec = selinux_superblock(inode->i_sb);
355 	/*
356 	 * As not all inode security structures are in a list, we check for
357 	 * empty list outside of the lock to make sure that we won't waste
358 	 * time taking a lock doing nothing.
359 	 *
360 	 * The list_del_init() function can be safely called more than once.
361 	 * It should not be possible for this function to be called with
362 	 * concurrent list_add(), but for better safety against future changes
363 	 * in the code, we use list_empty_careful() here.
364 	 */
365 	if (!list_empty_careful(&isec->list)) {
366 		spin_lock(&sbsec->isec_lock);
367 		list_del_init(&isec->list);
368 		spin_unlock(&sbsec->isec_lock);
369 	}
370 }
371 
372 struct selinux_mnt_opts {
373 	u32 fscontext_sid;
374 	u32 context_sid;
375 	u32 rootcontext_sid;
376 	u32 defcontext_sid;
377 };
378 
selinux_free_mnt_opts(void * mnt_opts)379 static void selinux_free_mnt_opts(void *mnt_opts)
380 {
381 	kfree(mnt_opts);
382 }
383 
384 enum {
385 	Opt_error = -1,
386 	Opt_context = 0,
387 	Opt_defcontext = 1,
388 	Opt_fscontext = 2,
389 	Opt_rootcontext = 3,
390 	Opt_seclabel = 4,
391 };
392 
393 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
394 static const struct {
395 	const char *name;
396 	int len;
397 	int opt;
398 	bool has_arg;
399 } tokens[] = {
400 	A(context, true),
401 	A(fscontext, true),
402 	A(defcontext, true),
403 	A(rootcontext, true),
404 	A(seclabel, false),
405 };
406 #undef A
407 
match_opt_prefix(char * s,int l,char ** arg)408 static int match_opt_prefix(char *s, int l, char **arg)
409 {
410 	unsigned int i;
411 
412 	for (i = 0; i < ARRAY_SIZE(tokens); i++) {
413 		size_t len = tokens[i].len;
414 		if (len > l || memcmp(s, tokens[i].name, len))
415 			continue;
416 		if (tokens[i].has_arg) {
417 			if (len == l || s[len] != '=')
418 				continue;
419 			*arg = s + len + 1;
420 		} else if (len != l)
421 			continue;
422 		return tokens[i].opt;
423 	}
424 	return Opt_error;
425 }
426 
427 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
428 
may_context_mount_sb_relabel(u32 sid,struct superblock_security_struct * sbsec,const struct cred * cred)429 static int may_context_mount_sb_relabel(u32 sid,
430 			struct superblock_security_struct *sbsec,
431 			const struct cred *cred)
432 {
433 	const struct task_security_struct *tsec = selinux_cred(cred);
434 	int rc;
435 
436 	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
437 			  FILESYSTEM__RELABELFROM, NULL);
438 	if (rc)
439 		return rc;
440 
441 	rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
442 			  FILESYSTEM__RELABELTO, NULL);
443 	return rc;
444 }
445 
may_context_mount_inode_relabel(u32 sid,struct superblock_security_struct * sbsec,const struct cred * cred)446 static int may_context_mount_inode_relabel(u32 sid,
447 			struct superblock_security_struct *sbsec,
448 			const struct cred *cred)
449 {
450 	const struct task_security_struct *tsec = selinux_cred(cred);
451 	int rc;
452 	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
453 			  FILESYSTEM__RELABELFROM, NULL);
454 	if (rc)
455 		return rc;
456 
457 	rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
458 			  FILESYSTEM__ASSOCIATE, NULL);
459 	return rc;
460 }
461 
selinux_is_genfs_special_handling(struct super_block * sb)462 static int selinux_is_genfs_special_handling(struct super_block *sb)
463 {
464 	/* Special handling. Genfs but also in-core setxattr handler */
465 	return	!strcmp(sb->s_type->name, "sysfs") ||
466 		!strcmp(sb->s_type->name, "pstore") ||
467 		!strcmp(sb->s_type->name, "debugfs") ||
468 		!strcmp(sb->s_type->name, "tracefs") ||
469 		!strcmp(sb->s_type->name, "rootfs") ||
470 		(selinux_policycap_cgroupseclabel() &&
471 		 (!strcmp(sb->s_type->name, "cgroup") ||
472 		  !strcmp(sb->s_type->name, "cgroup2")));
473 }
474 
selinux_is_sblabel_mnt(struct super_block * sb)475 static int selinux_is_sblabel_mnt(struct super_block *sb)
476 {
477 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
478 
479 	/*
480 	 * IMPORTANT: Double-check logic in this function when adding a new
481 	 * SECURITY_FS_USE_* definition!
482 	 */
483 	BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
484 
485 	switch (sbsec->behavior) {
486 	case SECURITY_FS_USE_XATTR:
487 	case SECURITY_FS_USE_TRANS:
488 	case SECURITY_FS_USE_TASK:
489 	case SECURITY_FS_USE_NATIVE:
490 		return 1;
491 
492 	case SECURITY_FS_USE_GENFS:
493 		return selinux_is_genfs_special_handling(sb);
494 
495 	/* Never allow relabeling on context mounts */
496 	case SECURITY_FS_USE_MNTPOINT:
497 	case SECURITY_FS_USE_NONE:
498 	default:
499 		return 0;
500 	}
501 }
502 
sb_check_xattr_support(struct super_block * sb)503 static int sb_check_xattr_support(struct super_block *sb)
504 {
505 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
506 	struct dentry *root = sb->s_root;
507 	struct inode *root_inode = d_backing_inode(root);
508 	u32 sid;
509 	int rc;
510 
511 	/*
512 	 * Make sure that the xattr handler exists and that no
513 	 * error other than -ENODATA is returned by getxattr on
514 	 * the root directory.  -ENODATA is ok, as this may be
515 	 * the first boot of the SELinux kernel before we have
516 	 * assigned xattr values to the filesystem.
517 	 */
518 	if (!(root_inode->i_opflags & IOP_XATTR)) {
519 		pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
520 			sb->s_id, sb->s_type->name);
521 		goto fallback;
522 	}
523 
524 	rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
525 	if (rc < 0 && rc != -ENODATA) {
526 		if (rc == -EOPNOTSUPP) {
527 			pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
528 				sb->s_id, sb->s_type->name);
529 			goto fallback;
530 		} else {
531 			pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
532 				sb->s_id, sb->s_type->name, -rc);
533 			return rc;
534 		}
535 	}
536 	return 0;
537 
538 fallback:
539 	/* No xattr support - try to fallback to genfs if possible. */
540 	rc = security_genfs_sid(sb->s_type->name, "/",
541 				SECCLASS_DIR, &sid);
542 	if (rc)
543 		return -EOPNOTSUPP;
544 
545 	pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
546 		sb->s_id, sb->s_type->name);
547 	sbsec->behavior = SECURITY_FS_USE_GENFS;
548 	sbsec->sid = sid;
549 	return 0;
550 }
551 
sb_finish_set_opts(struct super_block * sb)552 static int sb_finish_set_opts(struct super_block *sb)
553 {
554 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
555 	struct dentry *root = sb->s_root;
556 	struct inode *root_inode = d_backing_inode(root);
557 	int rc = 0;
558 
559 	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
560 		rc = sb_check_xattr_support(sb);
561 		if (rc)
562 			return rc;
563 	}
564 
565 	sbsec->flags |= SE_SBINITIALIZED;
566 
567 	/*
568 	 * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
569 	 * leave the flag untouched because sb_clone_mnt_opts might be handing
570 	 * us a superblock that needs the flag to be cleared.
571 	 */
572 	if (selinux_is_sblabel_mnt(sb))
573 		sbsec->flags |= SBLABEL_MNT;
574 	else
575 		sbsec->flags &= ~SBLABEL_MNT;
576 
577 	/* Initialize the root inode. */
578 	rc = inode_doinit_with_dentry(root_inode, root);
579 
580 	/* Initialize any other inodes associated with the superblock, e.g.
581 	   inodes created prior to initial policy load or inodes created
582 	   during get_sb by a pseudo filesystem that directly
583 	   populates itself. */
584 	spin_lock(&sbsec->isec_lock);
585 	while (!list_empty(&sbsec->isec_head)) {
586 		struct inode_security_struct *isec =
587 				list_first_entry(&sbsec->isec_head,
588 					   struct inode_security_struct, list);
589 		struct inode *inode = isec->inode;
590 		list_del_init(&isec->list);
591 		spin_unlock(&sbsec->isec_lock);
592 		inode = igrab(inode);
593 		if (inode) {
594 			if (!IS_PRIVATE(inode))
595 				inode_doinit_with_dentry(inode, NULL);
596 			iput(inode);
597 		}
598 		spin_lock(&sbsec->isec_lock);
599 	}
600 	spin_unlock(&sbsec->isec_lock);
601 	return rc;
602 }
603 
bad_option(struct superblock_security_struct * sbsec,char flag,u32 old_sid,u32 new_sid)604 static int bad_option(struct superblock_security_struct *sbsec, char flag,
605 		      u32 old_sid, u32 new_sid)
606 {
607 	char mnt_flags = sbsec->flags & SE_MNTMASK;
608 
609 	/* check if the old mount command had the same options */
610 	if (sbsec->flags & SE_SBINITIALIZED)
611 		if (!(sbsec->flags & flag) ||
612 		    (old_sid != new_sid))
613 			return 1;
614 
615 	/* check if we were passed the same options twice,
616 	 * aka someone passed context=a,context=b
617 	 */
618 	if (!(sbsec->flags & SE_SBINITIALIZED))
619 		if (mnt_flags & flag)
620 			return 1;
621 	return 0;
622 }
623 
624 /*
625  * Allow filesystems with binary mount data to explicitly set mount point
626  * labeling information.
627  */
selinux_set_mnt_opts(struct super_block * sb,void * mnt_opts,unsigned long kern_flags,unsigned long * set_kern_flags)628 static int selinux_set_mnt_opts(struct super_block *sb,
629 				void *mnt_opts,
630 				unsigned long kern_flags,
631 				unsigned long *set_kern_flags)
632 {
633 	const struct cred *cred = current_cred();
634 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
635 	struct dentry *root = sb->s_root;
636 	struct selinux_mnt_opts *opts = mnt_opts;
637 	struct inode_security_struct *root_isec;
638 	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
639 	u32 defcontext_sid = 0;
640 	int rc = 0;
641 
642 	/*
643 	 * Specifying internal flags without providing a place to
644 	 * place the results is not allowed
645 	 */
646 	if (kern_flags && !set_kern_flags)
647 		return -EINVAL;
648 
649 	mutex_lock(&sbsec->lock);
650 
651 	if (!selinux_initialized()) {
652 		if (!opts) {
653 			/* Defer initialization until selinux_complete_init,
654 			   after the initial policy is loaded and the security
655 			   server is ready to handle calls. */
656 			if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
657 				sbsec->flags |= SE_SBNATIVE;
658 				*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
659 			}
660 			goto out;
661 		}
662 		rc = -EINVAL;
663 		pr_warn("SELinux: Unable to set superblock options "
664 			"before the security server is initialized\n");
665 		goto out;
666 	}
667 
668 	/*
669 	 * Binary mount data FS will come through this function twice.  Once
670 	 * from an explicit call and once from the generic calls from the vfs.
671 	 * Since the generic VFS calls will not contain any security mount data
672 	 * we need to skip the double mount verification.
673 	 *
674 	 * This does open a hole in which we will not notice if the first
675 	 * mount using this sb set explicit options and a second mount using
676 	 * this sb does not set any security options.  (The first options
677 	 * will be used for both mounts)
678 	 */
679 	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
680 	    && !opts)
681 		goto out;
682 
683 	root_isec = backing_inode_security_novalidate(root);
684 
685 	/*
686 	 * parse the mount options, check if they are valid sids.
687 	 * also check if someone is trying to mount the same sb more
688 	 * than once with different security options.
689 	 */
690 	if (opts) {
691 		if (opts->fscontext_sid) {
692 			fscontext_sid = opts->fscontext_sid;
693 			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
694 					fscontext_sid))
695 				goto out_double_mount;
696 			sbsec->flags |= FSCONTEXT_MNT;
697 		}
698 		if (opts->context_sid) {
699 			context_sid = opts->context_sid;
700 			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
701 					context_sid))
702 				goto out_double_mount;
703 			sbsec->flags |= CONTEXT_MNT;
704 		}
705 		if (opts->rootcontext_sid) {
706 			rootcontext_sid = opts->rootcontext_sid;
707 			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
708 					rootcontext_sid))
709 				goto out_double_mount;
710 			sbsec->flags |= ROOTCONTEXT_MNT;
711 		}
712 		if (opts->defcontext_sid) {
713 			defcontext_sid = opts->defcontext_sid;
714 			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
715 					defcontext_sid))
716 				goto out_double_mount;
717 			sbsec->flags |= DEFCONTEXT_MNT;
718 		}
719 	}
720 
721 	if (sbsec->flags & SE_SBINITIALIZED) {
722 		/* previously mounted with options, but not on this attempt? */
723 		if ((sbsec->flags & SE_MNTMASK) && !opts)
724 			goto out_double_mount;
725 		rc = 0;
726 		goto out;
727 	}
728 
729 	if (strcmp(sb->s_type->name, "proc") == 0)
730 		sbsec->flags |= SE_SBPROC | SE_SBGENFS;
731 
732 	if (!strcmp(sb->s_type->name, "debugfs") ||
733 	    !strcmp(sb->s_type->name, "tracefs") ||
734 	    !strcmp(sb->s_type->name, "binder") ||
735 	    !strcmp(sb->s_type->name, "bpf") ||
736 	    !strcmp(sb->s_type->name, "pstore") ||
737 	    !strcmp(sb->s_type->name, "securityfs"))
738 		sbsec->flags |= SE_SBGENFS;
739 
740 	if (!strcmp(sb->s_type->name, "sysfs") ||
741 	    !strcmp(sb->s_type->name, "cgroup") ||
742 	    !strcmp(sb->s_type->name, "cgroup2"))
743 		sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
744 
745 	if (!sbsec->behavior) {
746 		/*
747 		 * Determine the labeling behavior to use for this
748 		 * filesystem type.
749 		 */
750 		rc = security_fs_use(sb);
751 		if (rc) {
752 			pr_warn("%s: security_fs_use(%s) returned %d\n",
753 					__func__, sb->s_type->name, rc);
754 			goto out;
755 		}
756 	}
757 
758 	/*
759 	 * If this is a user namespace mount and the filesystem type is not
760 	 * explicitly whitelisted, then no contexts are allowed on the command
761 	 * line and security labels must be ignored.
762 	 */
763 	if (sb->s_user_ns != &init_user_ns &&
764 	    strcmp(sb->s_type->name, "tmpfs") &&
765 	    strcmp(sb->s_type->name, "ramfs") &&
766 	    strcmp(sb->s_type->name, "devpts") &&
767 	    strcmp(sb->s_type->name, "overlay")) {
768 		if (context_sid || fscontext_sid || rootcontext_sid ||
769 		    defcontext_sid) {
770 			rc = -EACCES;
771 			goto out;
772 		}
773 		if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
774 			sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
775 			rc = security_transition_sid(current_sid(),
776 						     current_sid(),
777 						     SECCLASS_FILE, NULL,
778 						     &sbsec->mntpoint_sid);
779 			if (rc)
780 				goto out;
781 		}
782 		goto out_set_opts;
783 	}
784 
785 	/* sets the context of the superblock for the fs being mounted. */
786 	if (fscontext_sid) {
787 		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
788 		if (rc)
789 			goto out;
790 
791 		sbsec->sid = fscontext_sid;
792 	}
793 
794 	/*
795 	 * Switch to using mount point labeling behavior.
796 	 * sets the label used on all file below the mountpoint, and will set
797 	 * the superblock context if not already set.
798 	 */
799 	if (sbsec->flags & SE_SBNATIVE) {
800 		/*
801 		 * This means we are initializing a superblock that has been
802 		 * mounted before the SELinux was initialized and the
803 		 * filesystem requested native labeling. We had already
804 		 * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags
805 		 * in the original mount attempt, so now we just need to set
806 		 * the SECURITY_FS_USE_NATIVE behavior.
807 		 */
808 		sbsec->behavior = SECURITY_FS_USE_NATIVE;
809 	} else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
810 		sbsec->behavior = SECURITY_FS_USE_NATIVE;
811 		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
812 	}
813 
814 	if (context_sid) {
815 		if (!fscontext_sid) {
816 			rc = may_context_mount_sb_relabel(context_sid, sbsec,
817 							  cred);
818 			if (rc)
819 				goto out;
820 			sbsec->sid = context_sid;
821 		} else {
822 			rc = may_context_mount_inode_relabel(context_sid, sbsec,
823 							     cred);
824 			if (rc)
825 				goto out;
826 		}
827 		if (!rootcontext_sid)
828 			rootcontext_sid = context_sid;
829 
830 		sbsec->mntpoint_sid = context_sid;
831 		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
832 	}
833 
834 	if (rootcontext_sid) {
835 		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
836 						     cred);
837 		if (rc)
838 			goto out;
839 
840 		root_isec->sid = rootcontext_sid;
841 		root_isec->initialized = LABEL_INITIALIZED;
842 	}
843 
844 	if (defcontext_sid) {
845 		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
846 			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
847 			rc = -EINVAL;
848 			pr_warn("SELinux: defcontext option is "
849 			       "invalid for this filesystem type\n");
850 			goto out;
851 		}
852 
853 		if (defcontext_sid != sbsec->def_sid) {
854 			rc = may_context_mount_inode_relabel(defcontext_sid,
855 							     sbsec, cred);
856 			if (rc)
857 				goto out;
858 		}
859 
860 		sbsec->def_sid = defcontext_sid;
861 	}
862 
863 out_set_opts:
864 	rc = sb_finish_set_opts(sb);
865 out:
866 	mutex_unlock(&sbsec->lock);
867 	return rc;
868 out_double_mount:
869 	rc = -EINVAL;
870 	pr_warn("SELinux: mount invalid.  Same superblock, different "
871 	       "security settings for (dev %s, type %s)\n", sb->s_id,
872 	       sb->s_type->name);
873 	goto out;
874 }
875 
selinux_cmp_sb_context(const struct super_block * oldsb,const struct super_block * newsb)876 static int selinux_cmp_sb_context(const struct super_block *oldsb,
877 				    const struct super_block *newsb)
878 {
879 	struct superblock_security_struct *old = selinux_superblock(oldsb);
880 	struct superblock_security_struct *new = selinux_superblock(newsb);
881 	char oldflags = old->flags & SE_MNTMASK;
882 	char newflags = new->flags & SE_MNTMASK;
883 
884 	if (oldflags != newflags)
885 		goto mismatch;
886 	if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
887 		goto mismatch;
888 	if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
889 		goto mismatch;
890 	if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
891 		goto mismatch;
892 	if (oldflags & ROOTCONTEXT_MNT) {
893 		struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
894 		struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
895 		if (oldroot->sid != newroot->sid)
896 			goto mismatch;
897 	}
898 	return 0;
899 mismatch:
900 	pr_warn("SELinux: mount invalid.  Same superblock, "
901 			    "different security settings for (dev %s, "
902 			    "type %s)\n", newsb->s_id, newsb->s_type->name);
903 	return -EBUSY;
904 }
905 
selinux_sb_clone_mnt_opts(const struct super_block * oldsb,struct super_block * newsb,unsigned long kern_flags,unsigned long * set_kern_flags)906 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
907 					struct super_block *newsb,
908 					unsigned long kern_flags,
909 					unsigned long *set_kern_flags)
910 {
911 	int rc = 0;
912 	const struct superblock_security_struct *oldsbsec =
913 						selinux_superblock(oldsb);
914 	struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
915 
916 	int set_fscontext =	(oldsbsec->flags & FSCONTEXT_MNT);
917 	int set_context =	(oldsbsec->flags & CONTEXT_MNT);
918 	int set_rootcontext =	(oldsbsec->flags & ROOTCONTEXT_MNT);
919 
920 	/*
921 	 * Specifying internal flags without providing a place to
922 	 * place the results is not allowed.
923 	 */
924 	if (kern_flags && !set_kern_flags)
925 		return -EINVAL;
926 
927 	mutex_lock(&newsbsec->lock);
928 
929 	/*
930 	 * if the parent was able to be mounted it clearly had no special lsm
931 	 * mount options.  thus we can safely deal with this superblock later
932 	 */
933 	if (!selinux_initialized()) {
934 		if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
935 			newsbsec->flags |= SE_SBNATIVE;
936 			*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
937 		}
938 		goto out;
939 	}
940 
941 	/* how can we clone if the old one wasn't set up?? */
942 	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
943 
944 	/* if fs is reusing a sb, make sure that the contexts match */
945 	if (newsbsec->flags & SE_SBINITIALIZED) {
946 		mutex_unlock(&newsbsec->lock);
947 		if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
948 			*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
949 		return selinux_cmp_sb_context(oldsb, newsb);
950 	}
951 
952 	newsbsec->flags = oldsbsec->flags;
953 
954 	newsbsec->sid = oldsbsec->sid;
955 	newsbsec->def_sid = oldsbsec->def_sid;
956 	newsbsec->behavior = oldsbsec->behavior;
957 
958 	if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
959 		!(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
960 		rc = security_fs_use(newsb);
961 		if (rc)
962 			goto out;
963 	}
964 
965 	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
966 		newsbsec->behavior = SECURITY_FS_USE_NATIVE;
967 		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
968 	}
969 
970 	if (set_context) {
971 		u32 sid = oldsbsec->mntpoint_sid;
972 
973 		if (!set_fscontext)
974 			newsbsec->sid = sid;
975 		if (!set_rootcontext) {
976 			struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
977 			newisec->sid = sid;
978 		}
979 		newsbsec->mntpoint_sid = sid;
980 	}
981 	if (set_rootcontext) {
982 		const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
983 		struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
984 
985 		newisec->sid = oldisec->sid;
986 	}
987 
988 	sb_finish_set_opts(newsb);
989 out:
990 	mutex_unlock(&newsbsec->lock);
991 	return rc;
992 }
993 
994 /*
995  * NOTE: the caller is responsible for freeing the memory even if on error.
996  */
selinux_add_opt(int token,const char * s,void ** mnt_opts)997 static int selinux_add_opt(int token, const char *s, void **mnt_opts)
998 {
999 	struct selinux_mnt_opts *opts = *mnt_opts;
1000 	u32 *dst_sid;
1001 	int rc;
1002 
1003 	if (token == Opt_seclabel)
1004 		/* eaten and completely ignored */
1005 		return 0;
1006 	if (!s)
1007 		return -EINVAL;
1008 
1009 	if (!selinux_initialized()) {
1010 		pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n");
1011 		return -EINVAL;
1012 	}
1013 
1014 	if (!opts) {
1015 		opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1016 		if (!opts)
1017 			return -ENOMEM;
1018 		*mnt_opts = opts;
1019 	}
1020 
1021 	switch (token) {
1022 	case Opt_context:
1023 		if (opts->context_sid || opts->defcontext_sid)
1024 			goto err;
1025 		dst_sid = &opts->context_sid;
1026 		break;
1027 	case Opt_fscontext:
1028 		if (opts->fscontext_sid)
1029 			goto err;
1030 		dst_sid = &opts->fscontext_sid;
1031 		break;
1032 	case Opt_rootcontext:
1033 		if (opts->rootcontext_sid)
1034 			goto err;
1035 		dst_sid = &opts->rootcontext_sid;
1036 		break;
1037 	case Opt_defcontext:
1038 		if (opts->context_sid || opts->defcontext_sid)
1039 			goto err;
1040 		dst_sid = &opts->defcontext_sid;
1041 		break;
1042 	default:
1043 		WARN_ON(1);
1044 		return -EINVAL;
1045 	}
1046 	rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL);
1047 	if (rc)
1048 		pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n",
1049 			s, rc);
1050 	return rc;
1051 
1052 err:
1053 	pr_warn(SEL_MOUNT_FAIL_MSG);
1054 	return -EINVAL;
1055 }
1056 
show_sid(struct seq_file * m,u32 sid)1057 static int show_sid(struct seq_file *m, u32 sid)
1058 {
1059 	char *context = NULL;
1060 	u32 len;
1061 	int rc;
1062 
1063 	rc = security_sid_to_context(sid, &context, &len);
1064 	if (!rc) {
1065 		bool has_comma = strchr(context, ',');
1066 
1067 		seq_putc(m, '=');
1068 		if (has_comma)
1069 			seq_putc(m, '\"');
1070 		seq_escape(m, context, "\"\n\\");
1071 		if (has_comma)
1072 			seq_putc(m, '\"');
1073 	}
1074 	kfree(context);
1075 	return rc;
1076 }
1077 
selinux_sb_show_options(struct seq_file * m,struct super_block * sb)1078 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1079 {
1080 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
1081 	int rc;
1082 
1083 	if (!(sbsec->flags & SE_SBINITIALIZED))
1084 		return 0;
1085 
1086 	if (!selinux_initialized())
1087 		return 0;
1088 
1089 	if (sbsec->flags & FSCONTEXT_MNT) {
1090 		seq_putc(m, ',');
1091 		seq_puts(m, FSCONTEXT_STR);
1092 		rc = show_sid(m, sbsec->sid);
1093 		if (rc)
1094 			return rc;
1095 	}
1096 	if (sbsec->flags & CONTEXT_MNT) {
1097 		seq_putc(m, ',');
1098 		seq_puts(m, CONTEXT_STR);
1099 		rc = show_sid(m, sbsec->mntpoint_sid);
1100 		if (rc)
1101 			return rc;
1102 	}
1103 	if (sbsec->flags & DEFCONTEXT_MNT) {
1104 		seq_putc(m, ',');
1105 		seq_puts(m, DEFCONTEXT_STR);
1106 		rc = show_sid(m, sbsec->def_sid);
1107 		if (rc)
1108 			return rc;
1109 	}
1110 	if (sbsec->flags & ROOTCONTEXT_MNT) {
1111 		struct dentry *root = sb->s_root;
1112 		struct inode_security_struct *isec = backing_inode_security(root);
1113 		seq_putc(m, ',');
1114 		seq_puts(m, ROOTCONTEXT_STR);
1115 		rc = show_sid(m, isec->sid);
1116 		if (rc)
1117 			return rc;
1118 	}
1119 	if (sbsec->flags & SBLABEL_MNT) {
1120 		seq_putc(m, ',');
1121 		seq_puts(m, SECLABEL_STR);
1122 	}
1123 	return 0;
1124 }
1125 
inode_mode_to_security_class(umode_t mode)1126 static inline u16 inode_mode_to_security_class(umode_t mode)
1127 {
1128 	switch (mode & S_IFMT) {
1129 	case S_IFSOCK:
1130 		return SECCLASS_SOCK_FILE;
1131 	case S_IFLNK:
1132 		return SECCLASS_LNK_FILE;
1133 	case S_IFREG:
1134 		return SECCLASS_FILE;
1135 	case S_IFBLK:
1136 		return SECCLASS_BLK_FILE;
1137 	case S_IFDIR:
1138 		return SECCLASS_DIR;
1139 	case S_IFCHR:
1140 		return SECCLASS_CHR_FILE;
1141 	case S_IFIFO:
1142 		return SECCLASS_FIFO_FILE;
1143 
1144 	}
1145 
1146 	return SECCLASS_FILE;
1147 }
1148 
default_protocol_stream(int protocol)1149 static inline int default_protocol_stream(int protocol)
1150 {
1151 	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1152 		protocol == IPPROTO_MPTCP);
1153 }
1154 
default_protocol_dgram(int protocol)1155 static inline int default_protocol_dgram(int protocol)
1156 {
1157 	return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1158 }
1159 
socket_type_to_security_class(int family,int type,int protocol)1160 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1161 {
1162 	bool extsockclass = selinux_policycap_extsockclass();
1163 
1164 	switch (family) {
1165 	case PF_UNIX:
1166 		switch (type) {
1167 		case SOCK_STREAM:
1168 		case SOCK_SEQPACKET:
1169 			return SECCLASS_UNIX_STREAM_SOCKET;
1170 		case SOCK_DGRAM:
1171 		case SOCK_RAW:
1172 			return SECCLASS_UNIX_DGRAM_SOCKET;
1173 		}
1174 		break;
1175 	case PF_INET:
1176 	case PF_INET6:
1177 		switch (type) {
1178 		case SOCK_STREAM:
1179 		case SOCK_SEQPACKET:
1180 			if (default_protocol_stream(protocol))
1181 				return SECCLASS_TCP_SOCKET;
1182 			else if (extsockclass && protocol == IPPROTO_SCTP)
1183 				return SECCLASS_SCTP_SOCKET;
1184 			else
1185 				return SECCLASS_RAWIP_SOCKET;
1186 		case SOCK_DGRAM:
1187 			if (default_protocol_dgram(protocol))
1188 				return SECCLASS_UDP_SOCKET;
1189 			else if (extsockclass && (protocol == IPPROTO_ICMP ||
1190 						  protocol == IPPROTO_ICMPV6))
1191 				return SECCLASS_ICMP_SOCKET;
1192 			else
1193 				return SECCLASS_RAWIP_SOCKET;
1194 		case SOCK_DCCP:
1195 			return SECCLASS_DCCP_SOCKET;
1196 		default:
1197 			return SECCLASS_RAWIP_SOCKET;
1198 		}
1199 		break;
1200 	case PF_NETLINK:
1201 		switch (protocol) {
1202 		case NETLINK_ROUTE:
1203 			return SECCLASS_NETLINK_ROUTE_SOCKET;
1204 		case NETLINK_SOCK_DIAG:
1205 			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1206 		case NETLINK_NFLOG:
1207 			return SECCLASS_NETLINK_NFLOG_SOCKET;
1208 		case NETLINK_XFRM:
1209 			return SECCLASS_NETLINK_XFRM_SOCKET;
1210 		case NETLINK_SELINUX:
1211 			return SECCLASS_NETLINK_SELINUX_SOCKET;
1212 		case NETLINK_ISCSI:
1213 			return SECCLASS_NETLINK_ISCSI_SOCKET;
1214 		case NETLINK_AUDIT:
1215 			return SECCLASS_NETLINK_AUDIT_SOCKET;
1216 		case NETLINK_FIB_LOOKUP:
1217 			return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1218 		case NETLINK_CONNECTOR:
1219 			return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1220 		case NETLINK_NETFILTER:
1221 			return SECCLASS_NETLINK_NETFILTER_SOCKET;
1222 		case NETLINK_DNRTMSG:
1223 			return SECCLASS_NETLINK_DNRT_SOCKET;
1224 		case NETLINK_KOBJECT_UEVENT:
1225 			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1226 		case NETLINK_GENERIC:
1227 			return SECCLASS_NETLINK_GENERIC_SOCKET;
1228 		case NETLINK_SCSITRANSPORT:
1229 			return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1230 		case NETLINK_RDMA:
1231 			return SECCLASS_NETLINK_RDMA_SOCKET;
1232 		case NETLINK_CRYPTO:
1233 			return SECCLASS_NETLINK_CRYPTO_SOCKET;
1234 		default:
1235 			return SECCLASS_NETLINK_SOCKET;
1236 		}
1237 	case PF_PACKET:
1238 		return SECCLASS_PACKET_SOCKET;
1239 	case PF_KEY:
1240 		return SECCLASS_KEY_SOCKET;
1241 	case PF_APPLETALK:
1242 		return SECCLASS_APPLETALK_SOCKET;
1243 	}
1244 
1245 	if (extsockclass) {
1246 		switch (family) {
1247 		case PF_AX25:
1248 			return SECCLASS_AX25_SOCKET;
1249 		case PF_IPX:
1250 			return SECCLASS_IPX_SOCKET;
1251 		case PF_NETROM:
1252 			return SECCLASS_NETROM_SOCKET;
1253 		case PF_ATMPVC:
1254 			return SECCLASS_ATMPVC_SOCKET;
1255 		case PF_X25:
1256 			return SECCLASS_X25_SOCKET;
1257 		case PF_ROSE:
1258 			return SECCLASS_ROSE_SOCKET;
1259 		case PF_DECnet:
1260 			return SECCLASS_DECNET_SOCKET;
1261 		case PF_ATMSVC:
1262 			return SECCLASS_ATMSVC_SOCKET;
1263 		case PF_RDS:
1264 			return SECCLASS_RDS_SOCKET;
1265 		case PF_IRDA:
1266 			return SECCLASS_IRDA_SOCKET;
1267 		case PF_PPPOX:
1268 			return SECCLASS_PPPOX_SOCKET;
1269 		case PF_LLC:
1270 			return SECCLASS_LLC_SOCKET;
1271 		case PF_CAN:
1272 			return SECCLASS_CAN_SOCKET;
1273 		case PF_TIPC:
1274 			return SECCLASS_TIPC_SOCKET;
1275 		case PF_BLUETOOTH:
1276 			return SECCLASS_BLUETOOTH_SOCKET;
1277 		case PF_IUCV:
1278 			return SECCLASS_IUCV_SOCKET;
1279 		case PF_RXRPC:
1280 			return SECCLASS_RXRPC_SOCKET;
1281 		case PF_ISDN:
1282 			return SECCLASS_ISDN_SOCKET;
1283 		case PF_PHONET:
1284 			return SECCLASS_PHONET_SOCKET;
1285 		case PF_IEEE802154:
1286 			return SECCLASS_IEEE802154_SOCKET;
1287 		case PF_CAIF:
1288 			return SECCLASS_CAIF_SOCKET;
1289 		case PF_ALG:
1290 			return SECCLASS_ALG_SOCKET;
1291 		case PF_NFC:
1292 			return SECCLASS_NFC_SOCKET;
1293 		case PF_VSOCK:
1294 			return SECCLASS_VSOCK_SOCKET;
1295 		case PF_KCM:
1296 			return SECCLASS_KCM_SOCKET;
1297 		case PF_QIPCRTR:
1298 			return SECCLASS_QIPCRTR_SOCKET;
1299 		case PF_SMC:
1300 			return SECCLASS_SMC_SOCKET;
1301 		case PF_XDP:
1302 			return SECCLASS_XDP_SOCKET;
1303 		case PF_MCTP:
1304 			return SECCLASS_MCTP_SOCKET;
1305 #if PF_MAX > 46
1306 #error New address family defined, please update this function.
1307 #endif
1308 		}
1309 	}
1310 
1311 	return SECCLASS_SOCKET;
1312 }
1313 
selinux_genfs_get_sid(struct dentry * dentry,u16 tclass,u16 flags,u32 * sid)1314 static int selinux_genfs_get_sid(struct dentry *dentry,
1315 				 u16 tclass,
1316 				 u16 flags,
1317 				 u32 *sid)
1318 {
1319 	int rc;
1320 	struct super_block *sb = dentry->d_sb;
1321 	char *buffer, *path;
1322 
1323 	buffer = (char *)__get_free_page(GFP_KERNEL);
1324 	if (!buffer)
1325 		return -ENOMEM;
1326 
1327 	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1328 	if (IS_ERR(path))
1329 		rc = PTR_ERR(path);
1330 	else {
1331 		if (flags & SE_SBPROC) {
1332 			/* each process gets a /proc/PID/ entry. Strip off the
1333 			 * PID part to get a valid selinux labeling.
1334 			 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1335 			while (path[1] >= '0' && path[1] <= '9') {
1336 				path[1] = '/';
1337 				path++;
1338 			}
1339 		}
1340 		rc = security_genfs_sid(sb->s_type->name,
1341 					path, tclass, sid);
1342 		if (rc == -ENOENT) {
1343 			/* No match in policy, mark as unlabeled. */
1344 			*sid = SECINITSID_UNLABELED;
1345 			rc = 0;
1346 		}
1347 	}
1348 	free_page((unsigned long)buffer);
1349 	return rc;
1350 }
1351 
inode_doinit_use_xattr(struct inode * inode,struct dentry * dentry,u32 def_sid,u32 * sid)1352 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1353 				  u32 def_sid, u32 *sid)
1354 {
1355 #define INITCONTEXTLEN 255
1356 	char *context;
1357 	unsigned int len;
1358 	int rc;
1359 
1360 	len = INITCONTEXTLEN;
1361 	context = kmalloc(len + 1, GFP_NOFS);
1362 	if (!context)
1363 		return -ENOMEM;
1364 
1365 	context[len] = '\0';
1366 	rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1367 	if (rc == -ERANGE) {
1368 		kfree(context);
1369 
1370 		/* Need a larger buffer.  Query for the right size. */
1371 		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1372 		if (rc < 0)
1373 			return rc;
1374 
1375 		len = rc;
1376 		context = kmalloc(len + 1, GFP_NOFS);
1377 		if (!context)
1378 			return -ENOMEM;
1379 
1380 		context[len] = '\0';
1381 		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1382 				    context, len);
1383 	}
1384 	if (rc < 0) {
1385 		kfree(context);
1386 		if (rc != -ENODATA) {
1387 			pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
1388 				__func__, -rc, inode->i_sb->s_id, inode->i_ino);
1389 			return rc;
1390 		}
1391 		*sid = def_sid;
1392 		return 0;
1393 	}
1394 
1395 	rc = security_context_to_sid_default(context, rc, sid,
1396 					     def_sid, GFP_NOFS);
1397 	if (rc) {
1398 		char *dev = inode->i_sb->s_id;
1399 		unsigned long ino = inode->i_ino;
1400 
1401 		if (rc == -EINVAL) {
1402 			pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s.  This indicates you may need to relabel the inode or the filesystem in question.\n",
1403 					      ino, dev, context);
1404 		} else {
1405 			pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1406 				__func__, context, -rc, dev, ino);
1407 		}
1408 	}
1409 	kfree(context);
1410 	return 0;
1411 }
1412 
1413 /* The inode's security attributes must be initialized before first use. */
inode_doinit_with_dentry(struct inode * inode,struct dentry * opt_dentry)1414 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1415 {
1416 	struct superblock_security_struct *sbsec = NULL;
1417 	struct inode_security_struct *isec = selinux_inode(inode);
1418 	u32 task_sid, sid = 0;
1419 	u16 sclass;
1420 	struct dentry *dentry;
1421 	int rc = 0;
1422 
1423 	if (isec->initialized == LABEL_INITIALIZED)
1424 		return 0;
1425 
1426 	spin_lock(&isec->lock);
1427 	if (isec->initialized == LABEL_INITIALIZED)
1428 		goto out_unlock;
1429 
1430 	if (isec->sclass == SECCLASS_FILE)
1431 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
1432 
1433 	sbsec = selinux_superblock(inode->i_sb);
1434 	if (!(sbsec->flags & SE_SBINITIALIZED)) {
1435 		/* Defer initialization until selinux_complete_init,
1436 		   after the initial policy is loaded and the security
1437 		   server is ready to handle calls. */
1438 		spin_lock(&sbsec->isec_lock);
1439 		if (list_empty(&isec->list))
1440 			list_add(&isec->list, &sbsec->isec_head);
1441 		spin_unlock(&sbsec->isec_lock);
1442 		goto out_unlock;
1443 	}
1444 
1445 	sclass = isec->sclass;
1446 	task_sid = isec->task_sid;
1447 	sid = isec->sid;
1448 	isec->initialized = LABEL_PENDING;
1449 	spin_unlock(&isec->lock);
1450 
1451 	switch (sbsec->behavior) {
1452 	/*
1453 	 * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels
1454 	 * via xattr when called from delayed_superblock_init().
1455 	 */
1456 	case SECURITY_FS_USE_NATIVE:
1457 	case SECURITY_FS_USE_XATTR:
1458 		if (!(inode->i_opflags & IOP_XATTR)) {
1459 			sid = sbsec->def_sid;
1460 			break;
1461 		}
1462 		/* Need a dentry, since the xattr API requires one.
1463 		   Life would be simpler if we could just pass the inode. */
1464 		if (opt_dentry) {
1465 			/* Called from d_instantiate or d_splice_alias. */
1466 			dentry = dget(opt_dentry);
1467 		} else {
1468 			/*
1469 			 * Called from selinux_complete_init, try to find a dentry.
1470 			 * Some filesystems really want a connected one, so try
1471 			 * that first.  We could split SECURITY_FS_USE_XATTR in
1472 			 * two, depending upon that...
1473 			 */
1474 			dentry = d_find_alias(inode);
1475 			if (!dentry)
1476 				dentry = d_find_any_alias(inode);
1477 		}
1478 		if (!dentry) {
1479 			/*
1480 			 * this is can be hit on boot when a file is accessed
1481 			 * before the policy is loaded.  When we load policy we
1482 			 * may find inodes that have no dentry on the
1483 			 * sbsec->isec_head list.  No reason to complain as these
1484 			 * will get fixed up the next time we go through
1485 			 * inode_doinit with a dentry, before these inodes could
1486 			 * be used again by userspace.
1487 			 */
1488 			goto out_invalid;
1489 		}
1490 
1491 		rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1492 					    &sid);
1493 		dput(dentry);
1494 		if (rc)
1495 			goto out;
1496 		break;
1497 	case SECURITY_FS_USE_TASK:
1498 		sid = task_sid;
1499 		break;
1500 	case SECURITY_FS_USE_TRANS:
1501 		/* Default to the fs SID. */
1502 		sid = sbsec->sid;
1503 
1504 		/* Try to obtain a transition SID. */
1505 		rc = security_transition_sid(task_sid, sid,
1506 					     sclass, NULL, &sid);
1507 		if (rc)
1508 			goto out;
1509 		break;
1510 	case SECURITY_FS_USE_MNTPOINT:
1511 		sid = sbsec->mntpoint_sid;
1512 		break;
1513 	default:
1514 		/* Default to the fs superblock SID. */
1515 		sid = sbsec->sid;
1516 
1517 		if ((sbsec->flags & SE_SBGENFS) &&
1518 		     (!S_ISLNK(inode->i_mode) ||
1519 		      selinux_policycap_genfs_seclabel_symlinks())) {
1520 			/* We must have a dentry to determine the label on
1521 			 * procfs inodes */
1522 			if (opt_dentry) {
1523 				/* Called from d_instantiate or
1524 				 * d_splice_alias. */
1525 				dentry = dget(opt_dentry);
1526 			} else {
1527 				/* Called from selinux_complete_init, try to
1528 				 * find a dentry.  Some filesystems really want
1529 				 * a connected one, so try that first.
1530 				 */
1531 				dentry = d_find_alias(inode);
1532 				if (!dentry)
1533 					dentry = d_find_any_alias(inode);
1534 			}
1535 			/*
1536 			 * This can be hit on boot when a file is accessed
1537 			 * before the policy is loaded.  When we load policy we
1538 			 * may find inodes that have no dentry on the
1539 			 * sbsec->isec_head list.  No reason to complain as
1540 			 * these will get fixed up the next time we go through
1541 			 * inode_doinit() with a dentry, before these inodes
1542 			 * could be used again by userspace.
1543 			 */
1544 			if (!dentry)
1545 				goto out_invalid;
1546 			rc = selinux_genfs_get_sid(dentry, sclass,
1547 						   sbsec->flags, &sid);
1548 			if (rc) {
1549 				dput(dentry);
1550 				goto out;
1551 			}
1552 
1553 			if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1554 			    (inode->i_opflags & IOP_XATTR)) {
1555 				rc = inode_doinit_use_xattr(inode, dentry,
1556 							    sid, &sid);
1557 				if (rc) {
1558 					dput(dentry);
1559 					goto out;
1560 				}
1561 			}
1562 			dput(dentry);
1563 		}
1564 		break;
1565 	}
1566 
1567 out:
1568 	spin_lock(&isec->lock);
1569 	if (isec->initialized == LABEL_PENDING) {
1570 		if (rc) {
1571 			isec->initialized = LABEL_INVALID;
1572 			goto out_unlock;
1573 		}
1574 		isec->initialized = LABEL_INITIALIZED;
1575 		isec->sid = sid;
1576 	}
1577 
1578 out_unlock:
1579 	spin_unlock(&isec->lock);
1580 	return rc;
1581 
1582 out_invalid:
1583 	spin_lock(&isec->lock);
1584 	if (isec->initialized == LABEL_PENDING) {
1585 		isec->initialized = LABEL_INVALID;
1586 		isec->sid = sid;
1587 	}
1588 	spin_unlock(&isec->lock);
1589 	return 0;
1590 }
1591 
1592 /* Convert a Linux signal to an access vector. */
signal_to_av(int sig)1593 static inline u32 signal_to_av(int sig)
1594 {
1595 	u32 perm = 0;
1596 
1597 	switch (sig) {
1598 	case SIGCHLD:
1599 		/* Commonly granted from child to parent. */
1600 		perm = PROCESS__SIGCHLD;
1601 		break;
1602 	case SIGKILL:
1603 		/* Cannot be caught or ignored */
1604 		perm = PROCESS__SIGKILL;
1605 		break;
1606 	case SIGSTOP:
1607 		/* Cannot be caught or ignored */
1608 		perm = PROCESS__SIGSTOP;
1609 		break;
1610 	default:
1611 		/* All other signals. */
1612 		perm = PROCESS__SIGNAL;
1613 		break;
1614 	}
1615 
1616 	return perm;
1617 }
1618 
1619 #if CAP_LAST_CAP > 63
1620 #error Fix SELinux to handle capabilities > 63.
1621 #endif
1622 
1623 /* Check whether a task is allowed to use a capability. */
cred_has_capability(const struct cred * cred,int cap,unsigned int opts,bool initns)1624 static int cred_has_capability(const struct cred *cred,
1625 			       int cap, unsigned int opts, bool initns)
1626 {
1627 	struct common_audit_data ad;
1628 	struct av_decision avd;
1629 	u16 sclass;
1630 	u32 sid = cred_sid(cred);
1631 	u32 av = CAP_TO_MASK(cap);
1632 	int rc;
1633 
1634 	ad.type = LSM_AUDIT_DATA_CAP;
1635 	ad.u.cap = cap;
1636 
1637 	switch (CAP_TO_INDEX(cap)) {
1638 	case 0:
1639 		sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1640 		break;
1641 	case 1:
1642 		sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1643 		break;
1644 	default:
1645 		pr_err("SELinux:  out of range capability %d\n", cap);
1646 		BUG();
1647 		return -EINVAL;
1648 	}
1649 
1650 	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1651 	if (!(opts & CAP_OPT_NOAUDIT)) {
1652 		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1653 		if (rc2)
1654 			return rc2;
1655 	}
1656 	return rc;
1657 }
1658 
1659 /* Check whether a task has a particular permission to an inode.
1660    The 'adp' parameter is optional and allows other audit
1661    data to be passed (e.g. the dentry). */
inode_has_perm(const struct cred * cred,struct inode * inode,u32 perms,struct common_audit_data * adp)1662 static int inode_has_perm(const struct cred *cred,
1663 			  struct inode *inode,
1664 			  u32 perms,
1665 			  struct common_audit_data *adp)
1666 {
1667 	struct inode_security_struct *isec;
1668 	u32 sid;
1669 
1670 	if (unlikely(IS_PRIVATE(inode)))
1671 		return 0;
1672 
1673 	sid = cred_sid(cred);
1674 	isec = selinux_inode(inode);
1675 
1676 	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1677 }
1678 
1679 /* Same as inode_has_perm, but pass explicit audit data containing
1680    the dentry to help the auditing code to more easily generate the
1681    pathname if needed. */
dentry_has_perm(const struct cred * cred,struct dentry * dentry,u32 av)1682 static inline int dentry_has_perm(const struct cred *cred,
1683 				  struct dentry *dentry,
1684 				  u32 av)
1685 {
1686 	struct inode *inode = d_backing_inode(dentry);
1687 	struct common_audit_data ad;
1688 
1689 	ad.type = LSM_AUDIT_DATA_DENTRY;
1690 	ad.u.dentry = dentry;
1691 	__inode_security_revalidate(inode, dentry, true);
1692 	return inode_has_perm(cred, inode, av, &ad);
1693 }
1694 
1695 /* Same as inode_has_perm, but pass explicit audit data containing
1696    the path to help the auditing code to more easily generate the
1697    pathname if needed. */
path_has_perm(const struct cred * cred,const struct path * path,u32 av)1698 static inline int path_has_perm(const struct cred *cred,
1699 				const struct path *path,
1700 				u32 av)
1701 {
1702 	struct inode *inode = d_backing_inode(path->dentry);
1703 	struct common_audit_data ad;
1704 
1705 	ad.type = LSM_AUDIT_DATA_PATH;
1706 	ad.u.path = *path;
1707 	__inode_security_revalidate(inode, path->dentry, true);
1708 	return inode_has_perm(cred, inode, av, &ad);
1709 }
1710 
1711 /* Same as path_has_perm, but uses the inode from the file struct. */
file_path_has_perm(const struct cred * cred,struct file * file,u32 av)1712 static inline int file_path_has_perm(const struct cred *cred,
1713 				     struct file *file,
1714 				     u32 av)
1715 {
1716 	struct common_audit_data ad;
1717 
1718 	ad.type = LSM_AUDIT_DATA_FILE;
1719 	ad.u.file = file;
1720 	return inode_has_perm(cred, file_inode(file), av, &ad);
1721 }
1722 
1723 #ifdef CONFIG_BPF_SYSCALL
1724 static int bpf_fd_pass(const struct file *file, u32 sid);
1725 #endif
1726 
1727 /* Check whether a task can use an open file descriptor to
1728    access an inode in a given way.  Check access to the
1729    descriptor itself, and then use dentry_has_perm to
1730    check a particular permission to the file.
1731    Access to the descriptor is implicitly granted if it
1732    has the same SID as the process.  If av is zero, then
1733    access to the file is not checked, e.g. for cases
1734    where only the descriptor is affected like seek. */
file_has_perm(const struct cred * cred,struct file * file,u32 av)1735 static int file_has_perm(const struct cred *cred,
1736 			 struct file *file,
1737 			 u32 av)
1738 {
1739 	struct file_security_struct *fsec = selinux_file(file);
1740 	struct inode *inode = file_inode(file);
1741 	struct common_audit_data ad;
1742 	u32 sid = cred_sid(cred);
1743 	int rc;
1744 
1745 	ad.type = LSM_AUDIT_DATA_FILE;
1746 	ad.u.file = file;
1747 
1748 	if (sid != fsec->sid) {
1749 		rc = avc_has_perm(sid, fsec->sid,
1750 				  SECCLASS_FD,
1751 				  FD__USE,
1752 				  &ad);
1753 		if (rc)
1754 			goto out;
1755 	}
1756 
1757 #ifdef CONFIG_BPF_SYSCALL
1758 	rc = bpf_fd_pass(file, cred_sid(cred));
1759 	if (rc)
1760 		return rc;
1761 #endif
1762 
1763 	/* av is zero if only checking access to the descriptor. */
1764 	rc = 0;
1765 	if (av)
1766 		rc = inode_has_perm(cred, inode, av, &ad);
1767 
1768 out:
1769 	return rc;
1770 }
1771 
1772 /*
1773  * Determine the label for an inode that might be unioned.
1774  */
1775 static int
selinux_determine_inode_label(const struct task_security_struct * tsec,struct inode * dir,const struct qstr * name,u16 tclass,u32 * _new_isid)1776 selinux_determine_inode_label(const struct task_security_struct *tsec,
1777 				 struct inode *dir,
1778 				 const struct qstr *name, u16 tclass,
1779 				 u32 *_new_isid)
1780 {
1781 	const struct superblock_security_struct *sbsec =
1782 						selinux_superblock(dir->i_sb);
1783 
1784 	if ((sbsec->flags & SE_SBINITIALIZED) &&
1785 	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1786 		*_new_isid = sbsec->mntpoint_sid;
1787 	} else if ((sbsec->flags & SBLABEL_MNT) &&
1788 		   tsec->create_sid) {
1789 		*_new_isid = tsec->create_sid;
1790 	} else {
1791 		const struct inode_security_struct *dsec = inode_security(dir);
1792 		return security_transition_sid(tsec->sid,
1793 					       dsec->sid, tclass,
1794 					       name, _new_isid);
1795 	}
1796 
1797 	return 0;
1798 }
1799 
1800 /* Check whether a task can create a file. */
may_create(struct inode * dir,struct dentry * dentry,u16 tclass)1801 static int may_create(struct inode *dir,
1802 		      struct dentry *dentry,
1803 		      u16 tclass)
1804 {
1805 	const struct task_security_struct *tsec = selinux_cred(current_cred());
1806 	struct inode_security_struct *dsec;
1807 	struct superblock_security_struct *sbsec;
1808 	u32 sid, newsid;
1809 	struct common_audit_data ad;
1810 	int rc;
1811 
1812 	dsec = inode_security(dir);
1813 	sbsec = selinux_superblock(dir->i_sb);
1814 
1815 	sid = tsec->sid;
1816 
1817 	ad.type = LSM_AUDIT_DATA_DENTRY;
1818 	ad.u.dentry = dentry;
1819 
1820 	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1821 			  DIR__ADD_NAME | DIR__SEARCH,
1822 			  &ad);
1823 	if (rc)
1824 		return rc;
1825 
1826 	rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1827 					   &newsid);
1828 	if (rc)
1829 		return rc;
1830 
1831 	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1832 	if (rc)
1833 		return rc;
1834 
1835 	return avc_has_perm(newsid, sbsec->sid,
1836 			    SECCLASS_FILESYSTEM,
1837 			    FILESYSTEM__ASSOCIATE, &ad);
1838 }
1839 
1840 #define MAY_LINK	0
1841 #define MAY_UNLINK	1
1842 #define MAY_RMDIR	2
1843 
1844 /* Check whether a task can link, unlink, or rmdir a file/directory. */
may_link(struct inode * dir,struct dentry * dentry,int kind)1845 static int may_link(struct inode *dir,
1846 		    struct dentry *dentry,
1847 		    int kind)
1848 
1849 {
1850 	struct inode_security_struct *dsec, *isec;
1851 	struct common_audit_data ad;
1852 	u32 sid = current_sid();
1853 	u32 av;
1854 	int rc;
1855 
1856 	dsec = inode_security(dir);
1857 	isec = backing_inode_security(dentry);
1858 
1859 	ad.type = LSM_AUDIT_DATA_DENTRY;
1860 	ad.u.dentry = dentry;
1861 
1862 	av = DIR__SEARCH;
1863 	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1864 	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1865 	if (rc)
1866 		return rc;
1867 
1868 	switch (kind) {
1869 	case MAY_LINK:
1870 		av = FILE__LINK;
1871 		break;
1872 	case MAY_UNLINK:
1873 		av = FILE__UNLINK;
1874 		break;
1875 	case MAY_RMDIR:
1876 		av = DIR__RMDIR;
1877 		break;
1878 	default:
1879 		pr_warn("SELinux: %s:  unrecognized kind %d\n",
1880 			__func__, kind);
1881 		return 0;
1882 	}
1883 
1884 	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1885 	return rc;
1886 }
1887 
may_rename(struct inode * old_dir,struct dentry * old_dentry,struct inode * new_dir,struct dentry * new_dentry)1888 static inline int may_rename(struct inode *old_dir,
1889 			     struct dentry *old_dentry,
1890 			     struct inode *new_dir,
1891 			     struct dentry *new_dentry)
1892 {
1893 	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1894 	struct common_audit_data ad;
1895 	u32 sid = current_sid();
1896 	u32 av;
1897 	int old_is_dir, new_is_dir;
1898 	int rc;
1899 
1900 	old_dsec = inode_security(old_dir);
1901 	old_isec = backing_inode_security(old_dentry);
1902 	old_is_dir = d_is_dir(old_dentry);
1903 	new_dsec = inode_security(new_dir);
1904 
1905 	ad.type = LSM_AUDIT_DATA_DENTRY;
1906 
1907 	ad.u.dentry = old_dentry;
1908 	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1909 			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1910 	if (rc)
1911 		return rc;
1912 	rc = avc_has_perm(sid, old_isec->sid,
1913 			  old_isec->sclass, FILE__RENAME, &ad);
1914 	if (rc)
1915 		return rc;
1916 	if (old_is_dir && new_dir != old_dir) {
1917 		rc = avc_has_perm(sid, old_isec->sid,
1918 				  old_isec->sclass, DIR__REPARENT, &ad);
1919 		if (rc)
1920 			return rc;
1921 	}
1922 
1923 	ad.u.dentry = new_dentry;
1924 	av = DIR__ADD_NAME | DIR__SEARCH;
1925 	if (d_is_positive(new_dentry))
1926 		av |= DIR__REMOVE_NAME;
1927 	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1928 	if (rc)
1929 		return rc;
1930 	if (d_is_positive(new_dentry)) {
1931 		new_isec = backing_inode_security(new_dentry);
1932 		new_is_dir = d_is_dir(new_dentry);
1933 		rc = avc_has_perm(sid, new_isec->sid,
1934 				  new_isec->sclass,
1935 				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1936 		if (rc)
1937 			return rc;
1938 	}
1939 
1940 	return 0;
1941 }
1942 
1943 /* Check whether a task can perform a filesystem operation. */
superblock_has_perm(const struct cred * cred,const struct super_block * sb,u32 perms,struct common_audit_data * ad)1944 static int superblock_has_perm(const struct cred *cred,
1945 			       const struct super_block *sb,
1946 			       u32 perms,
1947 			       struct common_audit_data *ad)
1948 {
1949 	struct superblock_security_struct *sbsec;
1950 	u32 sid = cred_sid(cred);
1951 
1952 	sbsec = selinux_superblock(sb);
1953 	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1954 }
1955 
1956 /* Convert a Linux mode and permission mask to an access vector. */
file_mask_to_av(int mode,int mask)1957 static inline u32 file_mask_to_av(int mode, int mask)
1958 {
1959 	u32 av = 0;
1960 
1961 	if (!S_ISDIR(mode)) {
1962 		if (mask & MAY_EXEC)
1963 			av |= FILE__EXECUTE;
1964 		if (mask & MAY_READ)
1965 			av |= FILE__READ;
1966 
1967 		if (mask & MAY_APPEND)
1968 			av |= FILE__APPEND;
1969 		else if (mask & MAY_WRITE)
1970 			av |= FILE__WRITE;
1971 
1972 	} else {
1973 		if (mask & MAY_EXEC)
1974 			av |= DIR__SEARCH;
1975 		if (mask & MAY_WRITE)
1976 			av |= DIR__WRITE;
1977 		if (mask & MAY_READ)
1978 			av |= DIR__READ;
1979 	}
1980 
1981 	return av;
1982 }
1983 
1984 /* Convert a Linux file to an access vector. */
file_to_av(const struct file * file)1985 static inline u32 file_to_av(const struct file *file)
1986 {
1987 	u32 av = 0;
1988 
1989 	if (file->f_mode & FMODE_READ)
1990 		av |= FILE__READ;
1991 	if (file->f_mode & FMODE_WRITE) {
1992 		if (file->f_flags & O_APPEND)
1993 			av |= FILE__APPEND;
1994 		else
1995 			av |= FILE__WRITE;
1996 	}
1997 	if (!av) {
1998 		/*
1999 		 * Special file opened with flags 3 for ioctl-only use.
2000 		 */
2001 		av = FILE__IOCTL;
2002 	}
2003 
2004 	return av;
2005 }
2006 
2007 /*
2008  * Convert a file to an access vector and include the correct
2009  * open permission.
2010  */
open_file_to_av(struct file * file)2011 static inline u32 open_file_to_av(struct file *file)
2012 {
2013 	u32 av = file_to_av(file);
2014 	struct inode *inode = file_inode(file);
2015 
2016 	if (selinux_policycap_openperm() &&
2017 	    inode->i_sb->s_magic != SOCKFS_MAGIC)
2018 		av |= FILE__OPEN;
2019 
2020 	return av;
2021 }
2022 
2023 /* Hook functions begin here. */
2024 
selinux_binder_set_context_mgr(const struct cred * mgr)2025 static int selinux_binder_set_context_mgr(const struct cred *mgr)
2026 {
2027 	return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER,
2028 			    BINDER__SET_CONTEXT_MGR, NULL);
2029 }
2030 
selinux_binder_transaction(const struct cred * from,const struct cred * to)2031 static int selinux_binder_transaction(const struct cred *from,
2032 				      const struct cred *to)
2033 {
2034 	u32 mysid = current_sid();
2035 	u32 fromsid = cred_sid(from);
2036 	u32 tosid = cred_sid(to);
2037 	int rc;
2038 
2039 	if (mysid != fromsid) {
2040 		rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2041 				  BINDER__IMPERSONATE, NULL);
2042 		if (rc)
2043 			return rc;
2044 	}
2045 
2046 	return avc_has_perm(fromsid, tosid,
2047 			    SECCLASS_BINDER, BINDER__CALL, NULL);
2048 }
2049 
selinux_binder_transfer_binder(const struct cred * from,const struct cred * to)2050 static int selinux_binder_transfer_binder(const struct cred *from,
2051 					  const struct cred *to)
2052 {
2053 	return avc_has_perm(cred_sid(from), cred_sid(to),
2054 			    SECCLASS_BINDER, BINDER__TRANSFER,
2055 			    NULL);
2056 }
2057 
selinux_binder_transfer_file(const struct cred * from,const struct cred * to,const struct file * file)2058 static int selinux_binder_transfer_file(const struct cred *from,
2059 					const struct cred *to,
2060 					const struct file *file)
2061 {
2062 	u32 sid = cred_sid(to);
2063 	struct file_security_struct *fsec = selinux_file(file);
2064 	struct dentry *dentry = file->f_path.dentry;
2065 	struct inode_security_struct *isec;
2066 	struct common_audit_data ad;
2067 	int rc;
2068 
2069 	ad.type = LSM_AUDIT_DATA_PATH;
2070 	ad.u.path = file->f_path;
2071 
2072 	if (sid != fsec->sid) {
2073 		rc = avc_has_perm(sid, fsec->sid,
2074 				  SECCLASS_FD,
2075 				  FD__USE,
2076 				  &ad);
2077 		if (rc)
2078 			return rc;
2079 	}
2080 
2081 #ifdef CONFIG_BPF_SYSCALL
2082 	rc = bpf_fd_pass(file, sid);
2083 	if (rc)
2084 		return rc;
2085 #endif
2086 
2087 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2088 		return 0;
2089 
2090 	isec = backing_inode_security(dentry);
2091 	return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2092 			    &ad);
2093 }
2094 
selinux_ptrace_access_check(struct task_struct * child,unsigned int mode)2095 static int selinux_ptrace_access_check(struct task_struct *child,
2096 				       unsigned int mode)
2097 {
2098 	u32 sid = current_sid();
2099 	u32 csid = task_sid_obj(child);
2100 
2101 	if (mode & PTRACE_MODE_READ)
2102 		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ,
2103 				NULL);
2104 
2105 	return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE,
2106 			NULL);
2107 }
2108 
selinux_ptrace_traceme(struct task_struct * parent)2109 static int selinux_ptrace_traceme(struct task_struct *parent)
2110 {
2111 	return avc_has_perm(task_sid_obj(parent), task_sid_obj(current),
2112 			    SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2113 }
2114 
selinux_capget(const struct task_struct * target,kernel_cap_t * effective,kernel_cap_t * inheritable,kernel_cap_t * permitted)2115 static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective,
2116 			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
2117 {
2118 	return avc_has_perm(current_sid(), task_sid_obj(target),
2119 			SECCLASS_PROCESS, PROCESS__GETCAP, NULL);
2120 }
2121 
selinux_capset(struct cred * new,const struct cred * old,const kernel_cap_t * effective,const kernel_cap_t * inheritable,const kernel_cap_t * permitted)2122 static int selinux_capset(struct cred *new, const struct cred *old,
2123 			  const kernel_cap_t *effective,
2124 			  const kernel_cap_t *inheritable,
2125 			  const kernel_cap_t *permitted)
2126 {
2127 	return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2128 			    PROCESS__SETCAP, NULL);
2129 }
2130 
2131 /*
2132  * (This comment used to live with the selinux_task_setuid hook,
2133  * which was removed).
2134  *
2135  * Since setuid only affects the current process, and since the SELinux
2136  * controls are not based on the Linux identity attributes, SELinux does not
2137  * need to control this operation.  However, SELinux does control the use of
2138  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2139  */
2140 
selinux_capable(const struct cred * cred,struct user_namespace * ns,int cap,unsigned int opts)2141 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2142 			   int cap, unsigned int opts)
2143 {
2144 	return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2145 }
2146 
selinux_quotactl(int cmds,int type,int id,const struct super_block * sb)2147 static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb)
2148 {
2149 	const struct cred *cred = current_cred();
2150 	int rc = 0;
2151 
2152 	if (!sb)
2153 		return 0;
2154 
2155 	switch (cmds) {
2156 	case Q_SYNC:
2157 	case Q_QUOTAON:
2158 	case Q_QUOTAOFF:
2159 	case Q_SETINFO:
2160 	case Q_SETQUOTA:
2161 	case Q_XQUOTAOFF:
2162 	case Q_XQUOTAON:
2163 	case Q_XSETQLIM:
2164 		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2165 		break;
2166 	case Q_GETFMT:
2167 	case Q_GETINFO:
2168 	case Q_GETQUOTA:
2169 	case Q_XGETQUOTA:
2170 	case Q_XGETQSTAT:
2171 	case Q_XGETQSTATV:
2172 	case Q_XGETNEXTQUOTA:
2173 		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2174 		break;
2175 	default:
2176 		rc = 0;  /* let the kernel handle invalid cmds */
2177 		break;
2178 	}
2179 	return rc;
2180 }
2181 
selinux_quota_on(struct dentry * dentry)2182 static int selinux_quota_on(struct dentry *dentry)
2183 {
2184 	const struct cred *cred = current_cred();
2185 
2186 	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2187 }
2188 
selinux_syslog(int type)2189 static int selinux_syslog(int type)
2190 {
2191 	switch (type) {
2192 	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
2193 	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2194 		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2195 				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2196 	case SYSLOG_ACTION_CONSOLE_OFF:	/* Disable logging to console */
2197 	case SYSLOG_ACTION_CONSOLE_ON:	/* Enable logging to console */
2198 	/* Set level of messages printed to console */
2199 	case SYSLOG_ACTION_CONSOLE_LEVEL:
2200 		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2201 				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2202 				    NULL);
2203 	}
2204 	/* All other syslog types */
2205 	return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2206 			    SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2207 }
2208 
2209 /*
2210  * Check permission for allocating a new virtual mapping. Returns
2211  * 0 if permission is granted, negative error code if not.
2212  *
2213  * Do not audit the selinux permission check, as this is applied to all
2214  * processes that allocate mappings.
2215  */
selinux_vm_enough_memory(struct mm_struct * mm,long pages)2216 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2217 {
2218 	return cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2219 				   CAP_OPT_NOAUDIT, true);
2220 }
2221 
2222 /* binprm security operations */
2223 
ptrace_parent_sid(void)2224 static u32 ptrace_parent_sid(void)
2225 {
2226 	u32 sid = 0;
2227 	struct task_struct *tracer;
2228 
2229 	rcu_read_lock();
2230 	tracer = ptrace_parent(current);
2231 	if (tracer)
2232 		sid = task_sid_obj(tracer);
2233 	rcu_read_unlock();
2234 
2235 	return sid;
2236 }
2237 
check_nnp_nosuid(const struct linux_binprm * bprm,const struct task_security_struct * old_tsec,const struct task_security_struct * new_tsec)2238 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2239 			    const struct task_security_struct *old_tsec,
2240 			    const struct task_security_struct *new_tsec)
2241 {
2242 	int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2243 	int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2244 	int rc;
2245 	u32 av;
2246 
2247 	if (!nnp && !nosuid)
2248 		return 0; /* neither NNP nor nosuid */
2249 
2250 	if (new_tsec->sid == old_tsec->sid)
2251 		return 0; /* No change in credentials */
2252 
2253 	/*
2254 	 * If the policy enables the nnp_nosuid_transition policy capability,
2255 	 * then we permit transitions under NNP or nosuid if the
2256 	 * policy allows the corresponding permission between
2257 	 * the old and new contexts.
2258 	 */
2259 	if (selinux_policycap_nnp_nosuid_transition()) {
2260 		av = 0;
2261 		if (nnp)
2262 			av |= PROCESS2__NNP_TRANSITION;
2263 		if (nosuid)
2264 			av |= PROCESS2__NOSUID_TRANSITION;
2265 		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2266 				  SECCLASS_PROCESS2, av, NULL);
2267 		if (!rc)
2268 			return 0;
2269 	}
2270 
2271 	/*
2272 	 * We also permit NNP or nosuid transitions to bounded SIDs,
2273 	 * i.e. SIDs that are guaranteed to only be allowed a subset
2274 	 * of the permissions of the current SID.
2275 	 */
2276 	rc = security_bounded_transition(old_tsec->sid,
2277 					 new_tsec->sid);
2278 	if (!rc)
2279 		return 0;
2280 
2281 	/*
2282 	 * On failure, preserve the errno values for NNP vs nosuid.
2283 	 * NNP:  Operation not permitted for caller.
2284 	 * nosuid:  Permission denied to file.
2285 	 */
2286 	if (nnp)
2287 		return -EPERM;
2288 	return -EACCES;
2289 }
2290 
selinux_bprm_creds_for_exec(struct linux_binprm * bprm)2291 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2292 {
2293 	const struct task_security_struct *old_tsec;
2294 	struct task_security_struct *new_tsec;
2295 	struct inode_security_struct *isec;
2296 	struct common_audit_data ad;
2297 	struct inode *inode = file_inode(bprm->file);
2298 	int rc;
2299 
2300 	/* SELinux context only depends on initial program or script and not
2301 	 * the script interpreter */
2302 
2303 	old_tsec = selinux_cred(current_cred());
2304 	new_tsec = selinux_cred(bprm->cred);
2305 	isec = inode_security(inode);
2306 
2307 	/* Default to the current task SID. */
2308 	new_tsec->sid = old_tsec->sid;
2309 	new_tsec->osid = old_tsec->sid;
2310 
2311 	/* Reset fs, key, and sock SIDs on execve. */
2312 	new_tsec->create_sid = 0;
2313 	new_tsec->keycreate_sid = 0;
2314 	new_tsec->sockcreate_sid = 0;
2315 
2316 	/*
2317 	 * Before policy is loaded, label any task outside kernel space
2318 	 * as SECINITSID_INIT, so that any userspace tasks surviving from
2319 	 * early boot end up with a label different from SECINITSID_KERNEL
2320 	 * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL).
2321 	 */
2322 	if (!selinux_initialized()) {
2323 		new_tsec->sid = SECINITSID_INIT;
2324 		/* also clear the exec_sid just in case */
2325 		new_tsec->exec_sid = 0;
2326 		return 0;
2327 	}
2328 
2329 	if (old_tsec->exec_sid) {
2330 		new_tsec->sid = old_tsec->exec_sid;
2331 		/* Reset exec SID on execve. */
2332 		new_tsec->exec_sid = 0;
2333 
2334 		/* Fail on NNP or nosuid if not an allowed transition. */
2335 		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2336 		if (rc)
2337 			return rc;
2338 	} else {
2339 		/* Check for a default transition on this program. */
2340 		rc = security_transition_sid(old_tsec->sid,
2341 					     isec->sid, SECCLASS_PROCESS, NULL,
2342 					     &new_tsec->sid);
2343 		if (rc)
2344 			return rc;
2345 
2346 		/*
2347 		 * Fallback to old SID on NNP or nosuid if not an allowed
2348 		 * transition.
2349 		 */
2350 		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2351 		if (rc)
2352 			new_tsec->sid = old_tsec->sid;
2353 	}
2354 
2355 	ad.type = LSM_AUDIT_DATA_FILE;
2356 	ad.u.file = bprm->file;
2357 
2358 	if (new_tsec->sid == old_tsec->sid) {
2359 		rc = avc_has_perm(old_tsec->sid, isec->sid,
2360 				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2361 		if (rc)
2362 			return rc;
2363 	} else {
2364 		/* Check permissions for the transition. */
2365 		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2366 				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2367 		if (rc)
2368 			return rc;
2369 
2370 		rc = avc_has_perm(new_tsec->sid, isec->sid,
2371 				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2372 		if (rc)
2373 			return rc;
2374 
2375 		/* Check for shared state */
2376 		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2377 			rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2378 					  SECCLASS_PROCESS, PROCESS__SHARE,
2379 					  NULL);
2380 			if (rc)
2381 				return -EPERM;
2382 		}
2383 
2384 		/* Make sure that anyone attempting to ptrace over a task that
2385 		 * changes its SID has the appropriate permit */
2386 		if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2387 			u32 ptsid = ptrace_parent_sid();
2388 			if (ptsid != 0) {
2389 				rc = avc_has_perm(ptsid, new_tsec->sid,
2390 						  SECCLASS_PROCESS,
2391 						  PROCESS__PTRACE, NULL);
2392 				if (rc)
2393 					return -EPERM;
2394 			}
2395 		}
2396 
2397 		/* Clear any possibly unsafe personality bits on exec: */
2398 		bprm->per_clear |= PER_CLEAR_ON_SETID;
2399 
2400 		/* Enable secure mode for SIDs transitions unless
2401 		   the noatsecure permission is granted between
2402 		   the two SIDs, i.e. ahp returns 0. */
2403 		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2404 				  SECCLASS_PROCESS, PROCESS__NOATSECURE,
2405 				  NULL);
2406 		bprm->secureexec |= !!rc;
2407 	}
2408 
2409 	return 0;
2410 }
2411 
match_file(const void * p,struct file * file,unsigned fd)2412 static int match_file(const void *p, struct file *file, unsigned fd)
2413 {
2414 	return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2415 }
2416 
2417 /* Derived from fs/exec.c:flush_old_files. */
flush_unauthorized_files(const struct cred * cred,struct files_struct * files)2418 static inline void flush_unauthorized_files(const struct cred *cred,
2419 					    struct files_struct *files)
2420 {
2421 	struct file *file, *devnull = NULL;
2422 	struct tty_struct *tty;
2423 	int drop_tty = 0;
2424 	unsigned n;
2425 
2426 	tty = get_current_tty();
2427 	if (tty) {
2428 		spin_lock(&tty->files_lock);
2429 		if (!list_empty(&tty->tty_files)) {
2430 			struct tty_file_private *file_priv;
2431 
2432 			/* Revalidate access to controlling tty.
2433 			   Use file_path_has_perm on the tty path directly
2434 			   rather than using file_has_perm, as this particular
2435 			   open file may belong to another process and we are
2436 			   only interested in the inode-based check here. */
2437 			file_priv = list_first_entry(&tty->tty_files,
2438 						struct tty_file_private, list);
2439 			file = file_priv->file;
2440 			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2441 				drop_tty = 1;
2442 		}
2443 		spin_unlock(&tty->files_lock);
2444 		tty_kref_put(tty);
2445 	}
2446 	/* Reset controlling tty. */
2447 	if (drop_tty)
2448 		no_tty();
2449 
2450 	/* Revalidate access to inherited open files. */
2451 	n = iterate_fd(files, 0, match_file, cred);
2452 	if (!n) /* none found? */
2453 		return;
2454 
2455 	devnull = dentry_open(&selinux_null, O_RDWR, cred);
2456 	if (IS_ERR(devnull))
2457 		devnull = NULL;
2458 	/* replace all the matching ones with this */
2459 	do {
2460 		replace_fd(n - 1, devnull, 0);
2461 	} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2462 	if (devnull)
2463 		fput(devnull);
2464 }
2465 
2466 /*
2467  * Prepare a process for imminent new credential changes due to exec
2468  */
selinux_bprm_committing_creds(const struct linux_binprm * bprm)2469 static void selinux_bprm_committing_creds(const struct linux_binprm *bprm)
2470 {
2471 	struct task_security_struct *new_tsec;
2472 	struct rlimit *rlim, *initrlim;
2473 	int rc, i;
2474 
2475 	new_tsec = selinux_cred(bprm->cred);
2476 	if (new_tsec->sid == new_tsec->osid)
2477 		return;
2478 
2479 	/* Close files for which the new task SID is not authorized. */
2480 	flush_unauthorized_files(bprm->cred, current->files);
2481 
2482 	/* Always clear parent death signal on SID transitions. */
2483 	current->pdeath_signal = 0;
2484 
2485 	/* Check whether the new SID can inherit resource limits from the old
2486 	 * SID.  If not, reset all soft limits to the lower of the current
2487 	 * task's hard limit and the init task's soft limit.
2488 	 *
2489 	 * Note that the setting of hard limits (even to lower them) can be
2490 	 * controlled by the setrlimit check.  The inclusion of the init task's
2491 	 * soft limit into the computation is to avoid resetting soft limits
2492 	 * higher than the default soft limit for cases where the default is
2493 	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2494 	 */
2495 	rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2496 			  PROCESS__RLIMITINH, NULL);
2497 	if (rc) {
2498 		/* protect against do_prlimit() */
2499 		task_lock(current);
2500 		for (i = 0; i < RLIM_NLIMITS; i++) {
2501 			rlim = current->signal->rlim + i;
2502 			initrlim = init_task.signal->rlim + i;
2503 			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2504 		}
2505 		task_unlock(current);
2506 		if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2507 			update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2508 	}
2509 }
2510 
2511 /*
2512  * Clean up the process immediately after the installation of new credentials
2513  * due to exec
2514  */
selinux_bprm_committed_creds(const struct linux_binprm * bprm)2515 static void selinux_bprm_committed_creds(const struct linux_binprm *bprm)
2516 {
2517 	const struct task_security_struct *tsec = selinux_cred(current_cred());
2518 	u32 osid, sid;
2519 	int rc;
2520 
2521 	osid = tsec->osid;
2522 	sid = tsec->sid;
2523 
2524 	if (sid == osid)
2525 		return;
2526 
2527 	/* Check whether the new SID can inherit signal state from the old SID.
2528 	 * If not, clear itimers to avoid subsequent signal generation and
2529 	 * flush and unblock signals.
2530 	 *
2531 	 * This must occur _after_ the task SID has been updated so that any
2532 	 * kill done after the flush will be checked against the new SID.
2533 	 */
2534 	rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2535 	if (rc) {
2536 		clear_itimer();
2537 
2538 		spin_lock_irq(&unrcu_pointer(current->sighand)->siglock);
2539 		if (!fatal_signal_pending(current)) {
2540 			flush_sigqueue(&current->pending);
2541 			flush_sigqueue(&current->signal->shared_pending);
2542 			flush_signal_handlers(current, 1);
2543 			sigemptyset(&current->blocked);
2544 			recalc_sigpending();
2545 		}
2546 		spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock);
2547 	}
2548 
2549 	/* Wake up the parent if it is waiting so that it can recheck
2550 	 * wait permission to the new task SID. */
2551 	read_lock(&tasklist_lock);
2552 	__wake_up_parent(current, unrcu_pointer(current->real_parent));
2553 	read_unlock(&tasklist_lock);
2554 }
2555 
2556 /* superblock security operations */
2557 
selinux_sb_alloc_security(struct super_block * sb)2558 static int selinux_sb_alloc_security(struct super_block *sb)
2559 {
2560 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
2561 
2562 	mutex_init(&sbsec->lock);
2563 	INIT_LIST_HEAD(&sbsec->isec_head);
2564 	spin_lock_init(&sbsec->isec_lock);
2565 	sbsec->sid = SECINITSID_UNLABELED;
2566 	sbsec->def_sid = SECINITSID_FILE;
2567 	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2568 
2569 	return 0;
2570 }
2571 
opt_len(const char * s)2572 static inline int opt_len(const char *s)
2573 {
2574 	bool open_quote = false;
2575 	int len;
2576 	char c;
2577 
2578 	for (len = 0; (c = s[len]) != '\0'; len++) {
2579 		if (c == '"')
2580 			open_quote = !open_quote;
2581 		if (c == ',' && !open_quote)
2582 			break;
2583 	}
2584 	return len;
2585 }
2586 
selinux_sb_eat_lsm_opts(char * options,void ** mnt_opts)2587 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2588 {
2589 	char *from = options;
2590 	char *to = options;
2591 	bool first = true;
2592 	int rc;
2593 
2594 	while (1) {
2595 		int len = opt_len(from);
2596 		int token;
2597 		char *arg = NULL;
2598 
2599 		token = match_opt_prefix(from, len, &arg);
2600 
2601 		if (token != Opt_error) {
2602 			char *p, *q;
2603 
2604 			/* strip quotes */
2605 			if (arg) {
2606 				for (p = q = arg; p < from + len; p++) {
2607 					char c = *p;
2608 					if (c != '"')
2609 						*q++ = c;
2610 				}
2611 				arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2612 				if (!arg) {
2613 					rc = -ENOMEM;
2614 					goto free_opt;
2615 				}
2616 			}
2617 			rc = selinux_add_opt(token, arg, mnt_opts);
2618 			kfree(arg);
2619 			arg = NULL;
2620 			if (unlikely(rc)) {
2621 				goto free_opt;
2622 			}
2623 		} else {
2624 			if (!first) {	// copy with preceding comma
2625 				from--;
2626 				len++;
2627 			}
2628 			if (to != from)
2629 				memmove(to, from, len);
2630 			to += len;
2631 			first = false;
2632 		}
2633 		if (!from[len])
2634 			break;
2635 		from += len + 1;
2636 	}
2637 	*to = '\0';
2638 	return 0;
2639 
2640 free_opt:
2641 	if (*mnt_opts) {
2642 		selinux_free_mnt_opts(*mnt_opts);
2643 		*mnt_opts = NULL;
2644 	}
2645 	return rc;
2646 }
2647 
selinux_sb_mnt_opts_compat(struct super_block * sb,void * mnt_opts)2648 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
2649 {
2650 	struct selinux_mnt_opts *opts = mnt_opts;
2651 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
2652 
2653 	/*
2654 	 * Superblock not initialized (i.e. no options) - reject if any
2655 	 * options specified, otherwise accept.
2656 	 */
2657 	if (!(sbsec->flags & SE_SBINITIALIZED))
2658 		return opts ? 1 : 0;
2659 
2660 	/*
2661 	 * Superblock initialized and no options specified - reject if
2662 	 * superblock has any options set, otherwise accept.
2663 	 */
2664 	if (!opts)
2665 		return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2666 
2667 	if (opts->fscontext_sid) {
2668 		if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2669 			       opts->fscontext_sid))
2670 			return 1;
2671 	}
2672 	if (opts->context_sid) {
2673 		if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2674 			       opts->context_sid))
2675 			return 1;
2676 	}
2677 	if (opts->rootcontext_sid) {
2678 		struct inode_security_struct *root_isec;
2679 
2680 		root_isec = backing_inode_security(sb->s_root);
2681 		if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2682 			       opts->rootcontext_sid))
2683 			return 1;
2684 	}
2685 	if (opts->defcontext_sid) {
2686 		if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2687 			       opts->defcontext_sid))
2688 			return 1;
2689 	}
2690 	return 0;
2691 }
2692 
selinux_sb_remount(struct super_block * sb,void * mnt_opts)2693 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2694 {
2695 	struct selinux_mnt_opts *opts = mnt_opts;
2696 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
2697 
2698 	if (!(sbsec->flags & SE_SBINITIALIZED))
2699 		return 0;
2700 
2701 	if (!opts)
2702 		return 0;
2703 
2704 	if (opts->fscontext_sid) {
2705 		if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2706 			       opts->fscontext_sid))
2707 			goto out_bad_option;
2708 	}
2709 	if (opts->context_sid) {
2710 		if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2711 			       opts->context_sid))
2712 			goto out_bad_option;
2713 	}
2714 	if (opts->rootcontext_sid) {
2715 		struct inode_security_struct *root_isec;
2716 		root_isec = backing_inode_security(sb->s_root);
2717 		if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2718 			       opts->rootcontext_sid))
2719 			goto out_bad_option;
2720 	}
2721 	if (opts->defcontext_sid) {
2722 		if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2723 			       opts->defcontext_sid))
2724 			goto out_bad_option;
2725 	}
2726 	return 0;
2727 
2728 out_bad_option:
2729 	pr_warn("SELinux: unable to change security options "
2730 	       "during remount (dev %s, type=%s)\n", sb->s_id,
2731 	       sb->s_type->name);
2732 	return -EINVAL;
2733 }
2734 
selinux_sb_kern_mount(const struct super_block * sb)2735 static int selinux_sb_kern_mount(const struct super_block *sb)
2736 {
2737 	const struct cred *cred = current_cred();
2738 	struct common_audit_data ad;
2739 
2740 	ad.type = LSM_AUDIT_DATA_DENTRY;
2741 	ad.u.dentry = sb->s_root;
2742 	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2743 }
2744 
selinux_sb_statfs(struct dentry * dentry)2745 static int selinux_sb_statfs(struct dentry *dentry)
2746 {
2747 	const struct cred *cred = current_cred();
2748 	struct common_audit_data ad;
2749 
2750 	ad.type = LSM_AUDIT_DATA_DENTRY;
2751 	ad.u.dentry = dentry->d_sb->s_root;
2752 	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2753 }
2754 
selinux_mount(const char * dev_name,const struct path * path,const char * type,unsigned long flags,void * data)2755 static int selinux_mount(const char *dev_name,
2756 			 const struct path *path,
2757 			 const char *type,
2758 			 unsigned long flags,
2759 			 void *data)
2760 {
2761 	const struct cred *cred = current_cred();
2762 
2763 	if (flags & MS_REMOUNT)
2764 		return superblock_has_perm(cred, path->dentry->d_sb,
2765 					   FILESYSTEM__REMOUNT, NULL);
2766 	else
2767 		return path_has_perm(cred, path, FILE__MOUNTON);
2768 }
2769 
selinux_move_mount(const struct path * from_path,const struct path * to_path)2770 static int selinux_move_mount(const struct path *from_path,
2771 			      const struct path *to_path)
2772 {
2773 	const struct cred *cred = current_cred();
2774 
2775 	return path_has_perm(cred, to_path, FILE__MOUNTON);
2776 }
2777 
selinux_umount(struct vfsmount * mnt,int flags)2778 static int selinux_umount(struct vfsmount *mnt, int flags)
2779 {
2780 	const struct cred *cred = current_cred();
2781 
2782 	return superblock_has_perm(cred, mnt->mnt_sb,
2783 				   FILESYSTEM__UNMOUNT, NULL);
2784 }
2785 
selinux_fs_context_submount(struct fs_context * fc,struct super_block * reference)2786 static int selinux_fs_context_submount(struct fs_context *fc,
2787 				   struct super_block *reference)
2788 {
2789 	const struct superblock_security_struct *sbsec = selinux_superblock(reference);
2790 	struct selinux_mnt_opts *opts;
2791 
2792 	/*
2793 	 * Ensure that fc->security remains NULL when no options are set
2794 	 * as expected by selinux_set_mnt_opts().
2795 	 */
2796 	if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT)))
2797 		return 0;
2798 
2799 	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
2800 	if (!opts)
2801 		return -ENOMEM;
2802 
2803 	if (sbsec->flags & FSCONTEXT_MNT)
2804 		opts->fscontext_sid = sbsec->sid;
2805 	if (sbsec->flags & CONTEXT_MNT)
2806 		opts->context_sid = sbsec->mntpoint_sid;
2807 	if (sbsec->flags & DEFCONTEXT_MNT)
2808 		opts->defcontext_sid = sbsec->def_sid;
2809 	fc->security = opts;
2810 	return 0;
2811 }
2812 
selinux_fs_context_dup(struct fs_context * fc,struct fs_context * src_fc)2813 static int selinux_fs_context_dup(struct fs_context *fc,
2814 				  struct fs_context *src_fc)
2815 {
2816 	const struct selinux_mnt_opts *src = src_fc->security;
2817 
2818 	if (!src)
2819 		return 0;
2820 
2821 	fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL);
2822 	return fc->security ? 0 : -ENOMEM;
2823 }
2824 
2825 static const struct fs_parameter_spec selinux_fs_parameters[] = {
2826 	fsparam_string(CONTEXT_STR,	Opt_context),
2827 	fsparam_string(DEFCONTEXT_STR,	Opt_defcontext),
2828 	fsparam_string(FSCONTEXT_STR,	Opt_fscontext),
2829 	fsparam_string(ROOTCONTEXT_STR,	Opt_rootcontext),
2830 	fsparam_flag  (SECLABEL_STR,	Opt_seclabel),
2831 	{}
2832 };
2833 
selinux_fs_context_parse_param(struct fs_context * fc,struct fs_parameter * param)2834 static int selinux_fs_context_parse_param(struct fs_context *fc,
2835 					  struct fs_parameter *param)
2836 {
2837 	struct fs_parse_result result;
2838 	int opt;
2839 
2840 	opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2841 	if (opt < 0)
2842 		return opt;
2843 
2844 	return selinux_add_opt(opt, param->string, &fc->security);
2845 }
2846 
2847 /* inode security operations */
2848 
selinux_inode_alloc_security(struct inode * inode)2849 static int selinux_inode_alloc_security(struct inode *inode)
2850 {
2851 	struct inode_security_struct *isec = selinux_inode(inode);
2852 	u32 sid = current_sid();
2853 
2854 	spin_lock_init(&isec->lock);
2855 	INIT_LIST_HEAD(&isec->list);
2856 	isec->inode = inode;
2857 	isec->sid = SECINITSID_UNLABELED;
2858 	isec->sclass = SECCLASS_FILE;
2859 	isec->task_sid = sid;
2860 	isec->initialized = LABEL_INVALID;
2861 
2862 	return 0;
2863 }
2864 
selinux_inode_free_security(struct inode * inode)2865 static void selinux_inode_free_security(struct inode *inode)
2866 {
2867 	inode_free_security(inode);
2868 }
2869 
selinux_dentry_init_security(struct dentry * dentry,int mode,const struct qstr * name,const char ** xattr_name,struct lsm_context * cp)2870 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2871 					const struct qstr *name,
2872 					const char **xattr_name,
2873 					struct lsm_context *cp)
2874 {
2875 	u32 newsid;
2876 	int rc;
2877 
2878 	rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2879 					   d_inode(dentry->d_parent), name,
2880 					   inode_mode_to_security_class(mode),
2881 					   &newsid);
2882 	if (rc)
2883 		return rc;
2884 
2885 	if (xattr_name)
2886 		*xattr_name = XATTR_NAME_SELINUX;
2887 
2888 	cp->id = LSM_ID_SELINUX;
2889 	return security_sid_to_context(newsid, &cp->context, &cp->len);
2890 }
2891 
selinux_dentry_create_files_as(struct dentry * dentry,int mode,struct qstr * name,const struct cred * old,struct cred * new)2892 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2893 					  struct qstr *name,
2894 					  const struct cred *old,
2895 					  struct cred *new)
2896 {
2897 	u32 newsid;
2898 	int rc;
2899 	struct task_security_struct *tsec;
2900 
2901 	rc = selinux_determine_inode_label(selinux_cred(old),
2902 					   d_inode(dentry->d_parent), name,
2903 					   inode_mode_to_security_class(mode),
2904 					   &newsid);
2905 	if (rc)
2906 		return rc;
2907 
2908 	tsec = selinux_cred(new);
2909 	tsec->create_sid = newsid;
2910 	return 0;
2911 }
2912 
selinux_inode_init_security(struct inode * inode,struct inode * dir,const struct qstr * qstr,struct xattr * xattrs,int * xattr_count)2913 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2914 				       const struct qstr *qstr,
2915 				       struct xattr *xattrs, int *xattr_count)
2916 {
2917 	const struct task_security_struct *tsec = selinux_cred(current_cred());
2918 	struct superblock_security_struct *sbsec;
2919 	struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count);
2920 	u32 newsid, clen;
2921 	u16 newsclass;
2922 	int rc;
2923 	char *context;
2924 
2925 	sbsec = selinux_superblock(dir->i_sb);
2926 
2927 	newsid = tsec->create_sid;
2928 	newsclass = inode_mode_to_security_class(inode->i_mode);
2929 	rc = selinux_determine_inode_label(tsec, dir, qstr, newsclass, &newsid);
2930 	if (rc)
2931 		return rc;
2932 
2933 	/* Possibly defer initialization to selinux_complete_init. */
2934 	if (sbsec->flags & SE_SBINITIALIZED) {
2935 		struct inode_security_struct *isec = selinux_inode(inode);
2936 		isec->sclass = newsclass;
2937 		isec->sid = newsid;
2938 		isec->initialized = LABEL_INITIALIZED;
2939 	}
2940 
2941 	if (!selinux_initialized() ||
2942 	    !(sbsec->flags & SBLABEL_MNT))
2943 		return -EOPNOTSUPP;
2944 
2945 	if (xattr) {
2946 		rc = security_sid_to_context_force(newsid,
2947 						   &context, &clen);
2948 		if (rc)
2949 			return rc;
2950 		xattr->value = context;
2951 		xattr->value_len = clen;
2952 		xattr->name = XATTR_SELINUX_SUFFIX;
2953 	}
2954 
2955 	return 0;
2956 }
2957 
selinux_inode_init_security_anon(struct inode * inode,const struct qstr * name,const struct inode * context_inode)2958 static int selinux_inode_init_security_anon(struct inode *inode,
2959 					    const struct qstr *name,
2960 					    const struct inode *context_inode)
2961 {
2962 	u32 sid = current_sid();
2963 	struct common_audit_data ad;
2964 	struct inode_security_struct *isec;
2965 	int rc;
2966 
2967 	if (unlikely(!selinux_initialized()))
2968 		return 0;
2969 
2970 	isec = selinux_inode(inode);
2971 
2972 	/*
2973 	 * We only get here once per ephemeral inode.  The inode has
2974 	 * been initialized via inode_alloc_security but is otherwise
2975 	 * untouched.
2976 	 */
2977 
2978 	if (context_inode) {
2979 		struct inode_security_struct *context_isec =
2980 			selinux_inode(context_inode);
2981 		if (context_isec->initialized != LABEL_INITIALIZED) {
2982 			pr_err("SELinux:  context_inode is not initialized\n");
2983 			return -EACCES;
2984 		}
2985 
2986 		isec->sclass = context_isec->sclass;
2987 		isec->sid = context_isec->sid;
2988 	} else {
2989 		isec->sclass = SECCLASS_ANON_INODE;
2990 		rc = security_transition_sid(
2991 			sid, sid,
2992 			isec->sclass, name, &isec->sid);
2993 		if (rc)
2994 			return rc;
2995 	}
2996 
2997 	isec->initialized = LABEL_INITIALIZED;
2998 	/*
2999 	 * Now that we've initialized security, check whether we're
3000 	 * allowed to actually create this type of anonymous inode.
3001 	 */
3002 
3003 	ad.type = LSM_AUDIT_DATA_ANONINODE;
3004 	ad.u.anonclass = name ? (const char *)name->name : "?";
3005 
3006 	return avc_has_perm(sid,
3007 			    isec->sid,
3008 			    isec->sclass,
3009 			    FILE__CREATE,
3010 			    &ad);
3011 }
3012 
selinux_inode_create(struct inode * dir,struct dentry * dentry,umode_t mode)3013 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3014 {
3015 	return may_create(dir, dentry, SECCLASS_FILE);
3016 }
3017 
selinux_inode_link(struct dentry * old_dentry,struct inode * dir,struct dentry * new_dentry)3018 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3019 {
3020 	return may_link(dir, old_dentry, MAY_LINK);
3021 }
3022 
selinux_inode_unlink(struct inode * dir,struct dentry * dentry)3023 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3024 {
3025 	return may_link(dir, dentry, MAY_UNLINK);
3026 }
3027 
selinux_inode_symlink(struct inode * dir,struct dentry * dentry,const char * name)3028 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3029 {
3030 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
3031 }
3032 
selinux_inode_mkdir(struct inode * dir,struct dentry * dentry,umode_t mask)3033 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3034 {
3035 	return may_create(dir, dentry, SECCLASS_DIR);
3036 }
3037 
selinux_inode_rmdir(struct inode * dir,struct dentry * dentry)3038 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3039 {
3040 	return may_link(dir, dentry, MAY_RMDIR);
3041 }
3042 
selinux_inode_mknod(struct inode * dir,struct dentry * dentry,umode_t mode,dev_t dev)3043 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3044 {
3045 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
3046 }
3047 
selinux_inode_rename(struct inode * old_inode,struct dentry * old_dentry,struct inode * new_inode,struct dentry * new_dentry)3048 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3049 				struct inode *new_inode, struct dentry *new_dentry)
3050 {
3051 	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3052 }
3053 
selinux_inode_readlink(struct dentry * dentry)3054 static int selinux_inode_readlink(struct dentry *dentry)
3055 {
3056 	const struct cred *cred = current_cred();
3057 
3058 	return dentry_has_perm(cred, dentry, FILE__READ);
3059 }
3060 
selinux_inode_follow_link(struct dentry * dentry,struct inode * inode,bool rcu)3061 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3062 				     bool rcu)
3063 {
3064 	struct common_audit_data ad;
3065 	struct inode_security_struct *isec;
3066 	u32 sid = current_sid();
3067 
3068 	ad.type = LSM_AUDIT_DATA_DENTRY;
3069 	ad.u.dentry = dentry;
3070 	isec = inode_security_rcu(inode, rcu);
3071 	if (IS_ERR(isec))
3072 		return PTR_ERR(isec);
3073 
3074 	return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad);
3075 }
3076 
audit_inode_permission(struct inode * inode,u32 perms,u32 audited,u32 denied,int result)3077 static noinline int audit_inode_permission(struct inode *inode,
3078 					   u32 perms, u32 audited, u32 denied,
3079 					   int result)
3080 {
3081 	struct common_audit_data ad;
3082 	struct inode_security_struct *isec = selinux_inode(inode);
3083 
3084 	ad.type = LSM_AUDIT_DATA_INODE;
3085 	ad.u.inode = inode;
3086 
3087 	return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3088 			    audited, denied, result, &ad);
3089 }
3090 
selinux_inode_permission(struct inode * inode,int mask)3091 static int selinux_inode_permission(struct inode *inode, int mask)
3092 {
3093 	u32 perms;
3094 	bool from_access;
3095 	bool no_block = mask & MAY_NOT_BLOCK;
3096 	struct inode_security_struct *isec;
3097 	u32 sid = current_sid();
3098 	struct av_decision avd;
3099 	int rc, rc2;
3100 	u32 audited, denied;
3101 
3102 	from_access = mask & MAY_ACCESS;
3103 	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3104 
3105 	/* No permission to check.  Existence test. */
3106 	if (!mask)
3107 		return 0;
3108 
3109 	if (unlikely(IS_PRIVATE(inode)))
3110 		return 0;
3111 
3112 	perms = file_mask_to_av(inode->i_mode, mask);
3113 
3114 	isec = inode_security_rcu(inode, no_block);
3115 	if (IS_ERR(isec))
3116 		return PTR_ERR(isec);
3117 
3118 	rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0,
3119 				  &avd);
3120 	audited = avc_audit_required(perms, &avd, rc,
3121 				     from_access ? FILE__AUDIT_ACCESS : 0,
3122 				     &denied);
3123 	if (likely(!audited))
3124 		return rc;
3125 
3126 	rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3127 	if (rc2)
3128 		return rc2;
3129 	return rc;
3130 }
3131 
selinux_inode_setattr(struct mnt_idmap * idmap,struct dentry * dentry,struct iattr * iattr)3132 static int selinux_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
3133 				 struct iattr *iattr)
3134 {
3135 	const struct cred *cred = current_cred();
3136 	struct inode *inode = d_backing_inode(dentry);
3137 	unsigned int ia_valid = iattr->ia_valid;
3138 	u32 av = FILE__WRITE;
3139 
3140 	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3141 	if (ia_valid & ATTR_FORCE) {
3142 		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3143 			      ATTR_FORCE);
3144 		if (!ia_valid)
3145 			return 0;
3146 	}
3147 
3148 	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3149 			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3150 		return dentry_has_perm(cred, dentry, FILE__SETATTR);
3151 
3152 	if (selinux_policycap_openperm() &&
3153 	    inode->i_sb->s_magic != SOCKFS_MAGIC &&
3154 	    (ia_valid & ATTR_SIZE) &&
3155 	    !(ia_valid & ATTR_FILE))
3156 		av |= FILE__OPEN;
3157 
3158 	return dentry_has_perm(cred, dentry, av);
3159 }
3160 
selinux_inode_getattr(const struct path * path)3161 static int selinux_inode_getattr(const struct path *path)
3162 {
3163 	return path_has_perm(current_cred(), path, FILE__GETATTR);
3164 }
3165 
has_cap_mac_admin(bool audit)3166 static bool has_cap_mac_admin(bool audit)
3167 {
3168 	const struct cred *cred = current_cred();
3169 	unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3170 
3171 	if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3172 		return false;
3173 	if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3174 		return false;
3175 	return true;
3176 }
3177 
3178 /**
3179  * selinux_inode_xattr_skipcap - Skip the xattr capability checks?
3180  * @name: name of the xattr
3181  *
3182  * Returns 1 to indicate that SELinux "owns" the access control rights to xattrs
3183  * named @name; the LSM layer should avoid enforcing any traditional
3184  * capability based access controls on this xattr.  Returns 0 to indicate that
3185  * SELinux does not "own" the access control rights to xattrs named @name and is
3186  * deferring to the LSM layer for further access controls, including capability
3187  * based controls.
3188  */
selinux_inode_xattr_skipcap(const char * name)3189 static int selinux_inode_xattr_skipcap(const char *name)
3190 {
3191 	/* require capability check if not a selinux xattr */
3192 	return !strcmp(name, XATTR_NAME_SELINUX);
3193 }
3194 
selinux_inode_setxattr(struct mnt_idmap * idmap,struct dentry * dentry,const char * name,const void * value,size_t size,int flags)3195 static int selinux_inode_setxattr(struct mnt_idmap *idmap,
3196 				  struct dentry *dentry, const char *name,
3197 				  const void *value, size_t size, int flags)
3198 {
3199 	struct inode *inode = d_backing_inode(dentry);
3200 	struct inode_security_struct *isec;
3201 	struct superblock_security_struct *sbsec;
3202 	struct common_audit_data ad;
3203 	u32 newsid, sid = current_sid();
3204 	int rc = 0;
3205 
3206 	/* if not a selinux xattr, only check the ordinary setattr perm */
3207 	if (strcmp(name, XATTR_NAME_SELINUX))
3208 		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3209 
3210 	if (!selinux_initialized())
3211 		return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM);
3212 
3213 	sbsec = selinux_superblock(inode->i_sb);
3214 	if (!(sbsec->flags & SBLABEL_MNT))
3215 		return -EOPNOTSUPP;
3216 
3217 	if (!inode_owner_or_capable(idmap, inode))
3218 		return -EPERM;
3219 
3220 	ad.type = LSM_AUDIT_DATA_DENTRY;
3221 	ad.u.dentry = dentry;
3222 
3223 	isec = backing_inode_security(dentry);
3224 	rc = avc_has_perm(sid, isec->sid, isec->sclass,
3225 			  FILE__RELABELFROM, &ad);
3226 	if (rc)
3227 		return rc;
3228 
3229 	rc = security_context_to_sid(value, size, &newsid,
3230 				     GFP_KERNEL);
3231 	if (rc == -EINVAL) {
3232 		if (!has_cap_mac_admin(true)) {
3233 			struct audit_buffer *ab;
3234 			size_t audit_size;
3235 
3236 			/* We strip a nul only if it is at the end, otherwise the
3237 			 * context contains a nul and we should audit that */
3238 			if (value) {
3239 				const char *str = value;
3240 
3241 				if (str[size - 1] == '\0')
3242 					audit_size = size - 1;
3243 				else
3244 					audit_size = size;
3245 			} else {
3246 				audit_size = 0;
3247 			}
3248 			ab = audit_log_start(audit_context(),
3249 					     GFP_ATOMIC, AUDIT_SELINUX_ERR);
3250 			if (!ab)
3251 				return rc;
3252 			audit_log_format(ab, "op=setxattr invalid_context=");
3253 			audit_log_n_untrustedstring(ab, value, audit_size);
3254 			audit_log_end(ab);
3255 
3256 			return rc;
3257 		}
3258 		rc = security_context_to_sid_force(value,
3259 						   size, &newsid);
3260 	}
3261 	if (rc)
3262 		return rc;
3263 
3264 	rc = avc_has_perm(sid, newsid, isec->sclass,
3265 			  FILE__RELABELTO, &ad);
3266 	if (rc)
3267 		return rc;
3268 
3269 	rc = security_validate_transition(isec->sid, newsid,
3270 					  sid, isec->sclass);
3271 	if (rc)
3272 		return rc;
3273 
3274 	return avc_has_perm(newsid,
3275 			    sbsec->sid,
3276 			    SECCLASS_FILESYSTEM,
3277 			    FILESYSTEM__ASSOCIATE,
3278 			    &ad);
3279 }
3280 
selinux_inode_set_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name,struct posix_acl * kacl)3281 static int selinux_inode_set_acl(struct mnt_idmap *idmap,
3282 				 struct dentry *dentry, const char *acl_name,
3283 				 struct posix_acl *kacl)
3284 {
3285 	return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3286 }
3287 
selinux_inode_get_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)3288 static int selinux_inode_get_acl(struct mnt_idmap *idmap,
3289 				 struct dentry *dentry, const char *acl_name)
3290 {
3291 	return dentry_has_perm(current_cred(), dentry, FILE__GETATTR);
3292 }
3293 
selinux_inode_remove_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)3294 static int selinux_inode_remove_acl(struct mnt_idmap *idmap,
3295 				    struct dentry *dentry, const char *acl_name)
3296 {
3297 	return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3298 }
3299 
selinux_inode_post_setxattr(struct dentry * dentry,const char * name,const void * value,size_t size,int flags)3300 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3301 					const void *value, size_t size,
3302 					int flags)
3303 {
3304 	struct inode *inode = d_backing_inode(dentry);
3305 	struct inode_security_struct *isec;
3306 	u32 newsid;
3307 	int rc;
3308 
3309 	if (strcmp(name, XATTR_NAME_SELINUX)) {
3310 		/* Not an attribute we recognize, so nothing to do. */
3311 		return;
3312 	}
3313 
3314 	if (!selinux_initialized()) {
3315 		/* If we haven't even been initialized, then we can't validate
3316 		 * against a policy, so leave the label as invalid. It may
3317 		 * resolve to a valid label on the next revalidation try if
3318 		 * we've since initialized.
3319 		 */
3320 		return;
3321 	}
3322 
3323 	rc = security_context_to_sid_force(value, size,
3324 					   &newsid);
3325 	if (rc) {
3326 		pr_err("SELinux:  unable to map context to SID"
3327 		       "for (%s, %lu), rc=%d\n",
3328 		       inode->i_sb->s_id, inode->i_ino, -rc);
3329 		return;
3330 	}
3331 
3332 	isec = backing_inode_security(dentry);
3333 	spin_lock(&isec->lock);
3334 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3335 	isec->sid = newsid;
3336 	isec->initialized = LABEL_INITIALIZED;
3337 	spin_unlock(&isec->lock);
3338 }
3339 
selinux_inode_getxattr(struct dentry * dentry,const char * name)3340 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3341 {
3342 	const struct cred *cred = current_cred();
3343 
3344 	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3345 }
3346 
selinux_inode_listxattr(struct dentry * dentry)3347 static int selinux_inode_listxattr(struct dentry *dentry)
3348 {
3349 	const struct cred *cred = current_cred();
3350 
3351 	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3352 }
3353 
selinux_inode_removexattr(struct mnt_idmap * idmap,struct dentry * dentry,const char * name)3354 static int selinux_inode_removexattr(struct mnt_idmap *idmap,
3355 				     struct dentry *dentry, const char *name)
3356 {
3357 	/* if not a selinux xattr, only check the ordinary setattr perm */
3358 	if (strcmp(name, XATTR_NAME_SELINUX))
3359 		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3360 
3361 	if (!selinux_initialized())
3362 		return 0;
3363 
3364 	/* No one is allowed to remove a SELinux security label.
3365 	   You can change the label, but all data must be labeled. */
3366 	return -EACCES;
3367 }
3368 
selinux_path_notify(const struct path * path,u64 mask,unsigned int obj_type)3369 static int selinux_path_notify(const struct path *path, u64 mask,
3370 						unsigned int obj_type)
3371 {
3372 	int ret;
3373 	u32 perm;
3374 
3375 	struct common_audit_data ad;
3376 
3377 	ad.type = LSM_AUDIT_DATA_PATH;
3378 	ad.u.path = *path;
3379 
3380 	/*
3381 	 * Set permission needed based on the type of mark being set.
3382 	 * Performs an additional check for sb watches.
3383 	 */
3384 	switch (obj_type) {
3385 	case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3386 		perm = FILE__WATCH_MOUNT;
3387 		break;
3388 	case FSNOTIFY_OBJ_TYPE_SB:
3389 		perm = FILE__WATCH_SB;
3390 		ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3391 						FILESYSTEM__WATCH, &ad);
3392 		if (ret)
3393 			return ret;
3394 		break;
3395 	case FSNOTIFY_OBJ_TYPE_INODE:
3396 		perm = FILE__WATCH;
3397 		break;
3398 	default:
3399 		return -EINVAL;
3400 	}
3401 
3402 	/* blocking watches require the file:watch_with_perm permission */
3403 	if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3404 		perm |= FILE__WATCH_WITH_PERM;
3405 
3406 	/* watches on read-like events need the file:watch_reads permission */
3407 	if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_PRE_ACCESS |
3408 		    FS_CLOSE_NOWRITE))
3409 		perm |= FILE__WATCH_READS;
3410 
3411 	return path_has_perm(current_cred(), path, perm);
3412 }
3413 
3414 /*
3415  * Copy the inode security context value to the user.
3416  *
3417  * Permission check is handled by selinux_inode_getxattr hook.
3418  */
selinux_inode_getsecurity(struct mnt_idmap * idmap,struct inode * inode,const char * name,void ** buffer,bool alloc)3419 static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3420 				     struct inode *inode, const char *name,
3421 				     void **buffer, bool alloc)
3422 {
3423 	u32 size;
3424 	int error;
3425 	char *context = NULL;
3426 	struct inode_security_struct *isec;
3427 
3428 	/*
3429 	 * If we're not initialized yet, then we can't validate contexts, so
3430 	 * just let vfs_getxattr fall back to using the on-disk xattr.
3431 	 */
3432 	if (!selinux_initialized() ||
3433 	    strcmp(name, XATTR_SELINUX_SUFFIX))
3434 		return -EOPNOTSUPP;
3435 
3436 	/*
3437 	 * If the caller has CAP_MAC_ADMIN, then get the raw context
3438 	 * value even if it is not defined by current policy; otherwise,
3439 	 * use the in-core value under current policy.
3440 	 * Use the non-auditing forms of the permission checks since
3441 	 * getxattr may be called by unprivileged processes commonly
3442 	 * and lack of permission just means that we fall back to the
3443 	 * in-core context value, not a denial.
3444 	 */
3445 	isec = inode_security(inode);
3446 	if (has_cap_mac_admin(false))
3447 		error = security_sid_to_context_force(isec->sid, &context,
3448 						      &size);
3449 	else
3450 		error = security_sid_to_context(isec->sid,
3451 						&context, &size);
3452 	if (error)
3453 		return error;
3454 	error = size;
3455 	if (alloc) {
3456 		*buffer = context;
3457 		goto out_nofree;
3458 	}
3459 	kfree(context);
3460 out_nofree:
3461 	return error;
3462 }
3463 
selinux_inode_setsecurity(struct inode * inode,const char * name,const void * value,size_t size,int flags)3464 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3465 				     const void *value, size_t size, int flags)
3466 {
3467 	struct inode_security_struct *isec = inode_security_novalidate(inode);
3468 	struct superblock_security_struct *sbsec;
3469 	u32 newsid;
3470 	int rc;
3471 
3472 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
3473 		return -EOPNOTSUPP;
3474 
3475 	sbsec = selinux_superblock(inode->i_sb);
3476 	if (!(sbsec->flags & SBLABEL_MNT))
3477 		return -EOPNOTSUPP;
3478 
3479 	if (!value || !size)
3480 		return -EACCES;
3481 
3482 	rc = security_context_to_sid(value, size, &newsid,
3483 				     GFP_KERNEL);
3484 	if (rc)
3485 		return rc;
3486 
3487 	spin_lock(&isec->lock);
3488 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3489 	isec->sid = newsid;
3490 	isec->initialized = LABEL_INITIALIZED;
3491 	spin_unlock(&isec->lock);
3492 	return 0;
3493 }
3494 
selinux_inode_listsecurity(struct inode * inode,char * buffer,size_t buffer_size)3495 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3496 {
3497 	const int len = sizeof(XATTR_NAME_SELINUX);
3498 
3499 	if (!selinux_initialized())
3500 		return 0;
3501 
3502 	if (buffer && len <= buffer_size)
3503 		memcpy(buffer, XATTR_NAME_SELINUX, len);
3504 	return len;
3505 }
3506 
selinux_inode_getlsmprop(struct inode * inode,struct lsm_prop * prop)3507 static void selinux_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop)
3508 {
3509 	struct inode_security_struct *isec = inode_security_novalidate(inode);
3510 
3511 	prop->selinux.secid = isec->sid;
3512 }
3513 
selinux_inode_copy_up(struct dentry * src,struct cred ** new)3514 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3515 {
3516 	struct lsm_prop prop;
3517 	struct task_security_struct *tsec;
3518 	struct cred *new_creds = *new;
3519 
3520 	if (new_creds == NULL) {
3521 		new_creds = prepare_creds();
3522 		if (!new_creds)
3523 			return -ENOMEM;
3524 	}
3525 
3526 	tsec = selinux_cred(new_creds);
3527 	/* Get label from overlay inode and set it in create_sid */
3528 	selinux_inode_getlsmprop(d_inode(src), &prop);
3529 	tsec->create_sid = prop.selinux.secid;
3530 	*new = new_creds;
3531 	return 0;
3532 }
3533 
selinux_inode_copy_up_xattr(struct dentry * dentry,const char * name)3534 static int selinux_inode_copy_up_xattr(struct dentry *dentry, const char *name)
3535 {
3536 	/* The copy_up hook above sets the initial context on an inode, but we
3537 	 * don't then want to overwrite it by blindly copying all the lower
3538 	 * xattrs up.  Instead, filter out SELinux-related xattrs following
3539 	 * policy load.
3540 	 */
3541 	if (selinux_initialized() && !strcmp(name, XATTR_NAME_SELINUX))
3542 		return -ECANCELED; /* Discard */
3543 	/*
3544 	 * Any other attribute apart from SELINUX is not claimed, supported
3545 	 * by selinux.
3546 	 */
3547 	return -EOPNOTSUPP;
3548 }
3549 
3550 /* kernfs node operations */
3551 
selinux_kernfs_init_security(struct kernfs_node * kn_dir,struct kernfs_node * kn)3552 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3553 					struct kernfs_node *kn)
3554 {
3555 	const struct task_security_struct *tsec = selinux_cred(current_cred());
3556 	u32 parent_sid, newsid, clen;
3557 	int rc;
3558 	char *context;
3559 
3560 	rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3561 	if (rc == -ENODATA)
3562 		return 0;
3563 	else if (rc < 0)
3564 		return rc;
3565 
3566 	clen = (u32)rc;
3567 	context = kmalloc(clen, GFP_KERNEL);
3568 	if (!context)
3569 		return -ENOMEM;
3570 
3571 	rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3572 	if (rc < 0) {
3573 		kfree(context);
3574 		return rc;
3575 	}
3576 
3577 	rc = security_context_to_sid(context, clen, &parent_sid,
3578 				     GFP_KERNEL);
3579 	kfree(context);
3580 	if (rc)
3581 		return rc;
3582 
3583 	if (tsec->create_sid) {
3584 		newsid = tsec->create_sid;
3585 	} else {
3586 		u16 secclass = inode_mode_to_security_class(kn->mode);
3587 		struct qstr q;
3588 
3589 		q.name = kn->name;
3590 		q.hash_len = hashlen_string(kn_dir, kn->name);
3591 
3592 		rc = security_transition_sid(tsec->sid,
3593 					     parent_sid, secclass, &q,
3594 					     &newsid);
3595 		if (rc)
3596 			return rc;
3597 	}
3598 
3599 	rc = security_sid_to_context_force(newsid,
3600 					   &context, &clen);
3601 	if (rc)
3602 		return rc;
3603 
3604 	rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3605 			      XATTR_CREATE);
3606 	kfree(context);
3607 	return rc;
3608 }
3609 
3610 
3611 /* file security operations */
3612 
selinux_revalidate_file_permission(struct file * file,int mask)3613 static int selinux_revalidate_file_permission(struct file *file, int mask)
3614 {
3615 	const struct cred *cred = current_cred();
3616 	struct inode *inode = file_inode(file);
3617 
3618 	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3619 	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3620 		mask |= MAY_APPEND;
3621 
3622 	return file_has_perm(cred, file,
3623 			     file_mask_to_av(inode->i_mode, mask));
3624 }
3625 
selinux_file_permission(struct file * file,int mask)3626 static int selinux_file_permission(struct file *file, int mask)
3627 {
3628 	struct inode *inode = file_inode(file);
3629 	struct file_security_struct *fsec = selinux_file(file);
3630 	struct inode_security_struct *isec;
3631 	u32 sid = current_sid();
3632 
3633 	if (!mask)
3634 		/* No permission to check.  Existence test. */
3635 		return 0;
3636 
3637 	isec = inode_security(inode);
3638 	if (sid == fsec->sid && fsec->isid == isec->sid &&
3639 	    fsec->pseqno == avc_policy_seqno())
3640 		/* No change since file_open check. */
3641 		return 0;
3642 
3643 	return selinux_revalidate_file_permission(file, mask);
3644 }
3645 
selinux_file_alloc_security(struct file * file)3646 static int selinux_file_alloc_security(struct file *file)
3647 {
3648 	struct file_security_struct *fsec = selinux_file(file);
3649 	u32 sid = current_sid();
3650 
3651 	fsec->sid = sid;
3652 	fsec->fown_sid = sid;
3653 
3654 	return 0;
3655 }
3656 
3657 /*
3658  * Check whether a task has the ioctl permission and cmd
3659  * operation to an inode.
3660  */
ioctl_has_perm(const struct cred * cred,struct file * file,u32 requested,u16 cmd)3661 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3662 		u32 requested, u16 cmd)
3663 {
3664 	struct common_audit_data ad;
3665 	struct file_security_struct *fsec = selinux_file(file);
3666 	struct inode *inode = file_inode(file);
3667 	struct inode_security_struct *isec;
3668 	struct lsm_ioctlop_audit ioctl;
3669 	u32 ssid = cred_sid(cred);
3670 	int rc;
3671 	u8 driver = cmd >> 8;
3672 	u8 xperm = cmd & 0xff;
3673 
3674 	ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3675 	ad.u.op = &ioctl;
3676 	ad.u.op->cmd = cmd;
3677 	ad.u.op->path = file->f_path;
3678 
3679 	if (ssid != fsec->sid) {
3680 		rc = avc_has_perm(ssid, fsec->sid,
3681 				SECCLASS_FD,
3682 				FD__USE,
3683 				&ad);
3684 		if (rc)
3685 			goto out;
3686 	}
3687 
3688 	if (unlikely(IS_PRIVATE(inode)))
3689 		return 0;
3690 
3691 	isec = inode_security(inode);
3692 	rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, requested,
3693 				    driver, AVC_EXT_IOCTL, xperm, &ad);
3694 out:
3695 	return rc;
3696 }
3697 
selinux_file_ioctl(struct file * file,unsigned int cmd,unsigned long arg)3698 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3699 			      unsigned long arg)
3700 {
3701 	const struct cred *cred = current_cred();
3702 	int error = 0;
3703 
3704 	switch (cmd) {
3705 	case FIONREAD:
3706 	case FIBMAP:
3707 	case FIGETBSZ:
3708 	case FS_IOC_GETFLAGS:
3709 	case FS_IOC_GETVERSION:
3710 		error = file_has_perm(cred, file, FILE__GETATTR);
3711 		break;
3712 
3713 	case FS_IOC_SETFLAGS:
3714 	case FS_IOC_SETVERSION:
3715 		error = file_has_perm(cred, file, FILE__SETATTR);
3716 		break;
3717 
3718 	/* sys_ioctl() checks */
3719 	case FIONBIO:
3720 	case FIOASYNC:
3721 		error = file_has_perm(cred, file, 0);
3722 		break;
3723 
3724 	case KDSKBENT:
3725 	case KDSKBSENT:
3726 		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3727 					    CAP_OPT_NONE, true);
3728 		break;
3729 
3730 	case FIOCLEX:
3731 	case FIONCLEX:
3732 		if (!selinux_policycap_ioctl_skip_cloexec())
3733 			error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3734 		break;
3735 
3736 	/* default case assumes that the command will go
3737 	 * to the file's ioctl() function.
3738 	 */
3739 	default:
3740 		error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3741 	}
3742 	return error;
3743 }
3744 
selinux_file_ioctl_compat(struct file * file,unsigned int cmd,unsigned long arg)3745 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd,
3746 			      unsigned long arg)
3747 {
3748 	/*
3749 	 * If we are in a 64-bit kernel running 32-bit userspace, we need to
3750 	 * make sure we don't compare 32-bit flags to 64-bit flags.
3751 	 */
3752 	switch (cmd) {
3753 	case FS_IOC32_GETFLAGS:
3754 		cmd = FS_IOC_GETFLAGS;
3755 		break;
3756 	case FS_IOC32_SETFLAGS:
3757 		cmd = FS_IOC_SETFLAGS;
3758 		break;
3759 	case FS_IOC32_GETVERSION:
3760 		cmd = FS_IOC_GETVERSION;
3761 		break;
3762 	case FS_IOC32_SETVERSION:
3763 		cmd = FS_IOC_SETVERSION;
3764 		break;
3765 	default:
3766 		break;
3767 	}
3768 
3769 	return selinux_file_ioctl(file, cmd, arg);
3770 }
3771 
3772 static int default_noexec __ro_after_init;
3773 
file_map_prot_check(struct file * file,unsigned long prot,int shared)3774 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3775 {
3776 	const struct cred *cred = current_cred();
3777 	u32 sid = cred_sid(cred);
3778 	int rc = 0;
3779 
3780 	if (default_noexec &&
3781 	    (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3782 				   (!shared && (prot & PROT_WRITE)))) {
3783 		/*
3784 		 * We are making executable an anonymous mapping or a
3785 		 * private file mapping that will also be writable.
3786 		 * This has an additional check.
3787 		 */
3788 		rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3789 				  PROCESS__EXECMEM, NULL);
3790 		if (rc)
3791 			goto error;
3792 	}
3793 
3794 	if (file) {
3795 		/* read access is always possible with a mapping */
3796 		u32 av = FILE__READ;
3797 
3798 		/* write access only matters if the mapping is shared */
3799 		if (shared && (prot & PROT_WRITE))
3800 			av |= FILE__WRITE;
3801 
3802 		if (prot & PROT_EXEC)
3803 			av |= FILE__EXECUTE;
3804 
3805 		return file_has_perm(cred, file, av);
3806 	}
3807 
3808 error:
3809 	return rc;
3810 }
3811 
selinux_mmap_addr(unsigned long addr)3812 static int selinux_mmap_addr(unsigned long addr)
3813 {
3814 	int rc = 0;
3815 
3816 	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3817 		u32 sid = current_sid();
3818 		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3819 				  MEMPROTECT__MMAP_ZERO, NULL);
3820 	}
3821 
3822 	return rc;
3823 }
3824 
selinux_mmap_file(struct file * file,unsigned long reqprot __always_unused,unsigned long prot,unsigned long flags)3825 static int selinux_mmap_file(struct file *file,
3826 			     unsigned long reqprot __always_unused,
3827 			     unsigned long prot, unsigned long flags)
3828 {
3829 	struct common_audit_data ad;
3830 	int rc;
3831 
3832 	if (file) {
3833 		ad.type = LSM_AUDIT_DATA_FILE;
3834 		ad.u.file = file;
3835 		rc = inode_has_perm(current_cred(), file_inode(file),
3836 				    FILE__MAP, &ad);
3837 		if (rc)
3838 			return rc;
3839 	}
3840 
3841 	return file_map_prot_check(file, prot,
3842 				   (flags & MAP_TYPE) == MAP_SHARED);
3843 }
3844 
selinux_file_mprotect(struct vm_area_struct * vma,unsigned long reqprot __always_unused,unsigned long prot)3845 static int selinux_file_mprotect(struct vm_area_struct *vma,
3846 				 unsigned long reqprot __always_unused,
3847 				 unsigned long prot)
3848 {
3849 	const struct cred *cred = current_cred();
3850 	u32 sid = cred_sid(cred);
3851 
3852 	if (default_noexec &&
3853 	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3854 		int rc = 0;
3855 		/*
3856 		 * We don't use the vma_is_initial_heap() helper as it has
3857 		 * a history of problems and is currently broken on systems
3858 		 * where there is no heap, e.g. brk == start_brk.  Before
3859 		 * replacing the conditional below with vma_is_initial_heap(),
3860 		 * or something similar, please ensure that the logic is the
3861 		 * same as what we have below or you have tested every possible
3862 		 * corner case you can think to test.
3863 		 */
3864 		if (vma->vm_start >= vma->vm_mm->start_brk &&
3865 		    vma->vm_end <= vma->vm_mm->brk) {
3866 			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3867 					  PROCESS__EXECHEAP, NULL);
3868 		} else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
3869 			    vma_is_stack_for_current(vma))) {
3870 			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3871 					  PROCESS__EXECSTACK, NULL);
3872 		} else if (vma->vm_file && vma->anon_vma) {
3873 			/*
3874 			 * We are making executable a file mapping that has
3875 			 * had some COW done. Since pages might have been
3876 			 * written, check ability to execute the possibly
3877 			 * modified content.  This typically should only
3878 			 * occur for text relocations.
3879 			 */
3880 			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3881 		}
3882 		if (rc)
3883 			return rc;
3884 	}
3885 
3886 	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3887 }
3888 
selinux_file_lock(struct file * file,unsigned int cmd)3889 static int selinux_file_lock(struct file *file, unsigned int cmd)
3890 {
3891 	const struct cred *cred = current_cred();
3892 
3893 	return file_has_perm(cred, file, FILE__LOCK);
3894 }
3895 
selinux_file_fcntl(struct file * file,unsigned int cmd,unsigned long arg)3896 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3897 			      unsigned long arg)
3898 {
3899 	const struct cred *cred = current_cred();
3900 	int err = 0;
3901 
3902 	switch (cmd) {
3903 	case F_SETFL:
3904 		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3905 			err = file_has_perm(cred, file, FILE__WRITE);
3906 			break;
3907 		}
3908 		fallthrough;
3909 	case F_SETOWN:
3910 	case F_SETSIG:
3911 	case F_GETFL:
3912 	case F_GETOWN:
3913 	case F_GETSIG:
3914 	case F_GETOWNER_UIDS:
3915 		/* Just check FD__USE permission */
3916 		err = file_has_perm(cred, file, 0);
3917 		break;
3918 	case F_GETLK:
3919 	case F_SETLK:
3920 	case F_SETLKW:
3921 	case F_OFD_GETLK:
3922 	case F_OFD_SETLK:
3923 	case F_OFD_SETLKW:
3924 #if BITS_PER_LONG == 32
3925 	case F_GETLK64:
3926 	case F_SETLK64:
3927 	case F_SETLKW64:
3928 #endif
3929 		err = file_has_perm(cred, file, FILE__LOCK);
3930 		break;
3931 	}
3932 
3933 	return err;
3934 }
3935 
selinux_file_set_fowner(struct file * file)3936 static void selinux_file_set_fowner(struct file *file)
3937 {
3938 	struct file_security_struct *fsec;
3939 
3940 	fsec = selinux_file(file);
3941 	fsec->fown_sid = current_sid();
3942 }
3943 
selinux_file_send_sigiotask(struct task_struct * tsk,struct fown_struct * fown,int signum)3944 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3945 				       struct fown_struct *fown, int signum)
3946 {
3947 	struct file *file;
3948 	u32 sid = task_sid_obj(tsk);
3949 	u32 perm;
3950 	struct file_security_struct *fsec;
3951 
3952 	/* struct fown_struct is never outside the context of a struct file */
3953 	file = fown->file;
3954 
3955 	fsec = selinux_file(file);
3956 
3957 	if (!signum)
3958 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3959 	else
3960 		perm = signal_to_av(signum);
3961 
3962 	return avc_has_perm(fsec->fown_sid, sid,
3963 			    SECCLASS_PROCESS, perm, NULL);
3964 }
3965 
selinux_file_receive(struct file * file)3966 static int selinux_file_receive(struct file *file)
3967 {
3968 	const struct cred *cred = current_cred();
3969 
3970 	return file_has_perm(cred, file, file_to_av(file));
3971 }
3972 
selinux_file_open(struct file * file)3973 static int selinux_file_open(struct file *file)
3974 {
3975 	struct file_security_struct *fsec;
3976 	struct inode_security_struct *isec;
3977 
3978 	fsec = selinux_file(file);
3979 	isec = inode_security(file_inode(file));
3980 	/*
3981 	 * Save inode label and policy sequence number
3982 	 * at open-time so that selinux_file_permission
3983 	 * can determine whether revalidation is necessary.
3984 	 * Task label is already saved in the file security
3985 	 * struct as its SID.
3986 	 */
3987 	fsec->isid = isec->sid;
3988 	fsec->pseqno = avc_policy_seqno();
3989 	/*
3990 	 * Since the inode label or policy seqno may have changed
3991 	 * between the selinux_inode_permission check and the saving
3992 	 * of state above, recheck that access is still permitted.
3993 	 * Otherwise, access might never be revalidated against the
3994 	 * new inode label or new policy.
3995 	 * This check is not redundant - do not remove.
3996 	 */
3997 	return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3998 }
3999 
4000 /* task security operations */
4001 
selinux_task_alloc(struct task_struct * task,unsigned long clone_flags)4002 static int selinux_task_alloc(struct task_struct *task,
4003 			      unsigned long clone_flags)
4004 {
4005 	u32 sid = current_sid();
4006 
4007 	return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
4008 }
4009 
4010 /*
4011  * prepare a new set of credentials for modification
4012  */
selinux_cred_prepare(struct cred * new,const struct cred * old,gfp_t gfp)4013 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
4014 				gfp_t gfp)
4015 {
4016 	const struct task_security_struct *old_tsec = selinux_cred(old);
4017 	struct task_security_struct *tsec = selinux_cred(new);
4018 
4019 	*tsec = *old_tsec;
4020 	return 0;
4021 }
4022 
4023 /*
4024  * transfer the SELinux data to a blank set of creds
4025  */
selinux_cred_transfer(struct cred * new,const struct cred * old)4026 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4027 {
4028 	const struct task_security_struct *old_tsec = selinux_cred(old);
4029 	struct task_security_struct *tsec = selinux_cred(new);
4030 
4031 	*tsec = *old_tsec;
4032 }
4033 
selinux_cred_getsecid(const struct cred * c,u32 * secid)4034 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4035 {
4036 	*secid = cred_sid(c);
4037 }
4038 
selinux_cred_getlsmprop(const struct cred * c,struct lsm_prop * prop)4039 static void selinux_cred_getlsmprop(const struct cred *c, struct lsm_prop *prop)
4040 {
4041 	prop->selinux.secid = cred_sid(c);
4042 }
4043 
4044 /*
4045  * set the security data for a kernel service
4046  * - all the creation contexts are set to unlabelled
4047  */
selinux_kernel_act_as(struct cred * new,u32 secid)4048 static int selinux_kernel_act_as(struct cred *new, u32 secid)
4049 {
4050 	struct task_security_struct *tsec = selinux_cred(new);
4051 	u32 sid = current_sid();
4052 	int ret;
4053 
4054 	ret = avc_has_perm(sid, secid,
4055 			   SECCLASS_KERNEL_SERVICE,
4056 			   KERNEL_SERVICE__USE_AS_OVERRIDE,
4057 			   NULL);
4058 	if (ret == 0) {
4059 		tsec->sid = secid;
4060 		tsec->create_sid = 0;
4061 		tsec->keycreate_sid = 0;
4062 		tsec->sockcreate_sid = 0;
4063 	}
4064 	return ret;
4065 }
4066 
4067 /*
4068  * set the file creation context in a security record to the same as the
4069  * objective context of the specified inode
4070  */
selinux_kernel_create_files_as(struct cred * new,struct inode * inode)4071 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4072 {
4073 	struct inode_security_struct *isec = inode_security(inode);
4074 	struct task_security_struct *tsec = selinux_cred(new);
4075 	u32 sid = current_sid();
4076 	int ret;
4077 
4078 	ret = avc_has_perm(sid, isec->sid,
4079 			   SECCLASS_KERNEL_SERVICE,
4080 			   KERNEL_SERVICE__CREATE_FILES_AS,
4081 			   NULL);
4082 
4083 	if (ret == 0)
4084 		tsec->create_sid = isec->sid;
4085 	return ret;
4086 }
4087 
selinux_kernel_module_request(char * kmod_name)4088 static int selinux_kernel_module_request(char *kmod_name)
4089 {
4090 	struct common_audit_data ad;
4091 
4092 	ad.type = LSM_AUDIT_DATA_KMOD;
4093 	ad.u.kmod_name = kmod_name;
4094 
4095 	return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4096 			    SYSTEM__MODULE_REQUEST, &ad);
4097 }
4098 
selinux_kernel_module_from_file(struct file * file)4099 static int selinux_kernel_module_from_file(struct file *file)
4100 {
4101 	struct common_audit_data ad;
4102 	struct inode_security_struct *isec;
4103 	struct file_security_struct *fsec;
4104 	u32 sid = current_sid();
4105 	int rc;
4106 
4107 	/* init_module */
4108 	if (file == NULL)
4109 		return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
4110 					SYSTEM__MODULE_LOAD, NULL);
4111 
4112 	/* finit_module */
4113 
4114 	ad.type = LSM_AUDIT_DATA_FILE;
4115 	ad.u.file = file;
4116 
4117 	fsec = selinux_file(file);
4118 	if (sid != fsec->sid) {
4119 		rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4120 		if (rc)
4121 			return rc;
4122 	}
4123 
4124 	isec = inode_security(file_inode(file));
4125 	return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
4126 				SYSTEM__MODULE_LOAD, &ad);
4127 }
4128 
selinux_kernel_read_file(struct file * file,enum kernel_read_file_id id,bool contents)4129 static int selinux_kernel_read_file(struct file *file,
4130 				    enum kernel_read_file_id id,
4131 				    bool contents)
4132 {
4133 	int rc = 0;
4134 
4135 	switch (id) {
4136 	case READING_MODULE:
4137 		rc = selinux_kernel_module_from_file(contents ? file : NULL);
4138 		break;
4139 	default:
4140 		break;
4141 	}
4142 
4143 	return rc;
4144 }
4145 
selinux_kernel_load_data(enum kernel_load_data_id id,bool contents)4146 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4147 {
4148 	int rc = 0;
4149 
4150 	switch (id) {
4151 	case LOADING_MODULE:
4152 		rc = selinux_kernel_module_from_file(NULL);
4153 		break;
4154 	default:
4155 		break;
4156 	}
4157 
4158 	return rc;
4159 }
4160 
selinux_task_setpgid(struct task_struct * p,pid_t pgid)4161 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4162 {
4163 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4164 			    PROCESS__SETPGID, NULL);
4165 }
4166 
selinux_task_getpgid(struct task_struct * p)4167 static int selinux_task_getpgid(struct task_struct *p)
4168 {
4169 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4170 			    PROCESS__GETPGID, NULL);
4171 }
4172 
selinux_task_getsid(struct task_struct * p)4173 static int selinux_task_getsid(struct task_struct *p)
4174 {
4175 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4176 			    PROCESS__GETSESSION, NULL);
4177 }
4178 
selinux_current_getlsmprop_subj(struct lsm_prop * prop)4179 static void selinux_current_getlsmprop_subj(struct lsm_prop *prop)
4180 {
4181 	prop->selinux.secid = current_sid();
4182 }
4183 
selinux_task_getlsmprop_obj(struct task_struct * p,struct lsm_prop * prop)4184 static void selinux_task_getlsmprop_obj(struct task_struct *p,
4185 					struct lsm_prop *prop)
4186 {
4187 	prop->selinux.secid = task_sid_obj(p);
4188 }
4189 
selinux_task_setnice(struct task_struct * p,int nice)4190 static int selinux_task_setnice(struct task_struct *p, int nice)
4191 {
4192 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4193 			    PROCESS__SETSCHED, NULL);
4194 }
4195 
selinux_task_setioprio(struct task_struct * p,int ioprio)4196 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4197 {
4198 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4199 			    PROCESS__SETSCHED, NULL);
4200 }
4201 
selinux_task_getioprio(struct task_struct * p)4202 static int selinux_task_getioprio(struct task_struct *p)
4203 {
4204 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4205 			    PROCESS__GETSCHED, NULL);
4206 }
4207 
selinux_task_prlimit(const struct cred * cred,const struct cred * tcred,unsigned int flags)4208 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4209 				unsigned int flags)
4210 {
4211 	u32 av = 0;
4212 
4213 	if (!flags)
4214 		return 0;
4215 	if (flags & LSM_PRLIMIT_WRITE)
4216 		av |= PROCESS__SETRLIMIT;
4217 	if (flags & LSM_PRLIMIT_READ)
4218 		av |= PROCESS__GETRLIMIT;
4219 	return avc_has_perm(cred_sid(cred), cred_sid(tcred),
4220 			    SECCLASS_PROCESS, av, NULL);
4221 }
4222 
selinux_task_setrlimit(struct task_struct * p,unsigned int resource,struct rlimit * new_rlim)4223 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4224 		struct rlimit *new_rlim)
4225 {
4226 	struct rlimit *old_rlim = p->signal->rlim + resource;
4227 
4228 	/* Control the ability to change the hard limit (whether
4229 	   lowering or raising it), so that the hard limit can
4230 	   later be used as a safe reset point for the soft limit
4231 	   upon context transitions.  See selinux_bprm_committing_creds. */
4232 	if (old_rlim->rlim_max != new_rlim->rlim_max)
4233 		return avc_has_perm(current_sid(), task_sid_obj(p),
4234 				    SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4235 
4236 	return 0;
4237 }
4238 
selinux_task_setscheduler(struct task_struct * p)4239 static int selinux_task_setscheduler(struct task_struct *p)
4240 {
4241 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4242 			    PROCESS__SETSCHED, NULL);
4243 }
4244 
selinux_task_getscheduler(struct task_struct * p)4245 static int selinux_task_getscheduler(struct task_struct *p)
4246 {
4247 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4248 			    PROCESS__GETSCHED, NULL);
4249 }
4250 
selinux_task_movememory(struct task_struct * p)4251 static int selinux_task_movememory(struct task_struct *p)
4252 {
4253 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4254 			    PROCESS__SETSCHED, NULL);
4255 }
4256 
selinux_task_kill(struct task_struct * p,struct kernel_siginfo * info,int sig,const struct cred * cred)4257 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4258 				int sig, const struct cred *cred)
4259 {
4260 	u32 secid;
4261 	u32 perm;
4262 
4263 	if (!sig)
4264 		perm = PROCESS__SIGNULL; /* null signal; existence test */
4265 	else
4266 		perm = signal_to_av(sig);
4267 	if (!cred)
4268 		secid = current_sid();
4269 	else
4270 		secid = cred_sid(cred);
4271 	return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4272 }
4273 
selinux_task_to_inode(struct task_struct * p,struct inode * inode)4274 static void selinux_task_to_inode(struct task_struct *p,
4275 				  struct inode *inode)
4276 {
4277 	struct inode_security_struct *isec = selinux_inode(inode);
4278 	u32 sid = task_sid_obj(p);
4279 
4280 	spin_lock(&isec->lock);
4281 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
4282 	isec->sid = sid;
4283 	isec->initialized = LABEL_INITIALIZED;
4284 	spin_unlock(&isec->lock);
4285 }
4286 
selinux_userns_create(const struct cred * cred)4287 static int selinux_userns_create(const struct cred *cred)
4288 {
4289 	u32 sid = current_sid();
4290 
4291 	return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4292 			USER_NAMESPACE__CREATE, NULL);
4293 }
4294 
4295 /* Returns error only if unable to parse addresses */
selinux_parse_skb_ipv4(struct sk_buff * skb,struct common_audit_data * ad,u8 * proto)4296 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4297 			struct common_audit_data *ad, u8 *proto)
4298 {
4299 	int offset, ihlen, ret = -EINVAL;
4300 	struct iphdr _iph, *ih;
4301 
4302 	offset = skb_network_offset(skb);
4303 	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4304 	if (ih == NULL)
4305 		goto out;
4306 
4307 	ihlen = ih->ihl * 4;
4308 	if (ihlen < sizeof(_iph))
4309 		goto out;
4310 
4311 	ad->u.net->v4info.saddr = ih->saddr;
4312 	ad->u.net->v4info.daddr = ih->daddr;
4313 	ret = 0;
4314 
4315 	if (proto)
4316 		*proto = ih->protocol;
4317 
4318 	switch (ih->protocol) {
4319 	case IPPROTO_TCP: {
4320 		struct tcphdr _tcph, *th;
4321 
4322 		if (ntohs(ih->frag_off) & IP_OFFSET)
4323 			break;
4324 
4325 		offset += ihlen;
4326 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4327 		if (th == NULL)
4328 			break;
4329 
4330 		ad->u.net->sport = th->source;
4331 		ad->u.net->dport = th->dest;
4332 		break;
4333 	}
4334 
4335 	case IPPROTO_UDP: {
4336 		struct udphdr _udph, *uh;
4337 
4338 		if (ntohs(ih->frag_off) & IP_OFFSET)
4339 			break;
4340 
4341 		offset += ihlen;
4342 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4343 		if (uh == NULL)
4344 			break;
4345 
4346 		ad->u.net->sport = uh->source;
4347 		ad->u.net->dport = uh->dest;
4348 		break;
4349 	}
4350 
4351 	case IPPROTO_DCCP: {
4352 		struct dccp_hdr _dccph, *dh;
4353 
4354 		if (ntohs(ih->frag_off) & IP_OFFSET)
4355 			break;
4356 
4357 		offset += ihlen;
4358 		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4359 		if (dh == NULL)
4360 			break;
4361 
4362 		ad->u.net->sport = dh->dccph_sport;
4363 		ad->u.net->dport = dh->dccph_dport;
4364 		break;
4365 	}
4366 
4367 #if IS_ENABLED(CONFIG_IP_SCTP)
4368 	case IPPROTO_SCTP: {
4369 		struct sctphdr _sctph, *sh;
4370 
4371 		if (ntohs(ih->frag_off) & IP_OFFSET)
4372 			break;
4373 
4374 		offset += ihlen;
4375 		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4376 		if (sh == NULL)
4377 			break;
4378 
4379 		ad->u.net->sport = sh->source;
4380 		ad->u.net->dport = sh->dest;
4381 		break;
4382 	}
4383 #endif
4384 	default:
4385 		break;
4386 	}
4387 out:
4388 	return ret;
4389 }
4390 
4391 #if IS_ENABLED(CONFIG_IPV6)
4392 
4393 /* Returns error only if unable to parse addresses */
selinux_parse_skb_ipv6(struct sk_buff * skb,struct common_audit_data * ad,u8 * proto)4394 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4395 			struct common_audit_data *ad, u8 *proto)
4396 {
4397 	u8 nexthdr;
4398 	int ret = -EINVAL, offset;
4399 	struct ipv6hdr _ipv6h, *ip6;
4400 	__be16 frag_off;
4401 
4402 	offset = skb_network_offset(skb);
4403 	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4404 	if (ip6 == NULL)
4405 		goto out;
4406 
4407 	ad->u.net->v6info.saddr = ip6->saddr;
4408 	ad->u.net->v6info.daddr = ip6->daddr;
4409 	ret = 0;
4410 
4411 	nexthdr = ip6->nexthdr;
4412 	offset += sizeof(_ipv6h);
4413 	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4414 	if (offset < 0)
4415 		goto out;
4416 
4417 	if (proto)
4418 		*proto = nexthdr;
4419 
4420 	switch (nexthdr) {
4421 	case IPPROTO_TCP: {
4422 		struct tcphdr _tcph, *th;
4423 
4424 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4425 		if (th == NULL)
4426 			break;
4427 
4428 		ad->u.net->sport = th->source;
4429 		ad->u.net->dport = th->dest;
4430 		break;
4431 	}
4432 
4433 	case IPPROTO_UDP: {
4434 		struct udphdr _udph, *uh;
4435 
4436 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4437 		if (uh == NULL)
4438 			break;
4439 
4440 		ad->u.net->sport = uh->source;
4441 		ad->u.net->dport = uh->dest;
4442 		break;
4443 	}
4444 
4445 	case IPPROTO_DCCP: {
4446 		struct dccp_hdr _dccph, *dh;
4447 
4448 		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4449 		if (dh == NULL)
4450 			break;
4451 
4452 		ad->u.net->sport = dh->dccph_sport;
4453 		ad->u.net->dport = dh->dccph_dport;
4454 		break;
4455 	}
4456 
4457 #if IS_ENABLED(CONFIG_IP_SCTP)
4458 	case IPPROTO_SCTP: {
4459 		struct sctphdr _sctph, *sh;
4460 
4461 		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4462 		if (sh == NULL)
4463 			break;
4464 
4465 		ad->u.net->sport = sh->source;
4466 		ad->u.net->dport = sh->dest;
4467 		break;
4468 	}
4469 #endif
4470 	/* includes fragments */
4471 	default:
4472 		break;
4473 	}
4474 out:
4475 	return ret;
4476 }
4477 
4478 #endif /* IPV6 */
4479 
selinux_parse_skb(struct sk_buff * skb,struct common_audit_data * ad,char ** _addrp,int src,u8 * proto)4480 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4481 			     char **_addrp, int src, u8 *proto)
4482 {
4483 	char *addrp;
4484 	int ret;
4485 
4486 	switch (ad->u.net->family) {
4487 	case PF_INET:
4488 		ret = selinux_parse_skb_ipv4(skb, ad, proto);
4489 		if (ret)
4490 			goto parse_error;
4491 		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4492 				       &ad->u.net->v4info.daddr);
4493 		goto okay;
4494 
4495 #if IS_ENABLED(CONFIG_IPV6)
4496 	case PF_INET6:
4497 		ret = selinux_parse_skb_ipv6(skb, ad, proto);
4498 		if (ret)
4499 			goto parse_error;
4500 		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4501 				       &ad->u.net->v6info.daddr);
4502 		goto okay;
4503 #endif	/* IPV6 */
4504 	default:
4505 		addrp = NULL;
4506 		goto okay;
4507 	}
4508 
4509 parse_error:
4510 	pr_warn(
4511 	       "SELinux: failure in selinux_parse_skb(),"
4512 	       " unable to parse packet\n");
4513 	return ret;
4514 
4515 okay:
4516 	if (_addrp)
4517 		*_addrp = addrp;
4518 	return 0;
4519 }
4520 
4521 /**
4522  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4523  * @skb: the packet
4524  * @family: protocol family
4525  * @sid: the packet's peer label SID
4526  *
4527  * Description:
4528  * Check the various different forms of network peer labeling and determine
4529  * the peer label/SID for the packet; most of the magic actually occurs in
4530  * the security server function security_net_peersid_cmp().  The function
4531  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4532  * or -EACCES if @sid is invalid due to inconsistencies with the different
4533  * peer labels.
4534  *
4535  */
selinux_skb_peerlbl_sid(struct sk_buff * skb,u16 family,u32 * sid)4536 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4537 {
4538 	int err;
4539 	u32 xfrm_sid;
4540 	u32 nlbl_sid;
4541 	u32 nlbl_type;
4542 
4543 	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4544 	if (unlikely(err))
4545 		return -EACCES;
4546 	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4547 	if (unlikely(err))
4548 		return -EACCES;
4549 
4550 	err = security_net_peersid_resolve(nlbl_sid,
4551 					   nlbl_type, xfrm_sid, sid);
4552 	if (unlikely(err)) {
4553 		pr_warn(
4554 		       "SELinux: failure in selinux_skb_peerlbl_sid(),"
4555 		       " unable to determine packet's peer label\n");
4556 		return -EACCES;
4557 	}
4558 
4559 	return 0;
4560 }
4561 
4562 /**
4563  * selinux_conn_sid - Determine the child socket label for a connection
4564  * @sk_sid: the parent socket's SID
4565  * @skb_sid: the packet's SID
4566  * @conn_sid: the resulting connection SID
4567  *
4568  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4569  * combined with the MLS information from @skb_sid in order to create
4570  * @conn_sid.  If @skb_sid is not valid then @conn_sid is simply a copy
4571  * of @sk_sid.  Returns zero on success, negative values on failure.
4572  *
4573  */
selinux_conn_sid(u32 sk_sid,u32 skb_sid,u32 * conn_sid)4574 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4575 {
4576 	int err = 0;
4577 
4578 	if (skb_sid != SECSID_NULL)
4579 		err = security_sid_mls_copy(sk_sid, skb_sid,
4580 					    conn_sid);
4581 	else
4582 		*conn_sid = sk_sid;
4583 
4584 	return err;
4585 }
4586 
4587 /* socket security operations */
4588 
socket_sockcreate_sid(const struct task_security_struct * tsec,u16 secclass,u32 * socksid)4589 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4590 				 u16 secclass, u32 *socksid)
4591 {
4592 	if (tsec->sockcreate_sid > SECSID_NULL) {
4593 		*socksid = tsec->sockcreate_sid;
4594 		return 0;
4595 	}
4596 
4597 	return security_transition_sid(tsec->sid, tsec->sid,
4598 				       secclass, NULL, socksid);
4599 }
4600 
sock_skip_has_perm(u32 sid)4601 static bool sock_skip_has_perm(u32 sid)
4602 {
4603 	if (sid == SECINITSID_KERNEL)
4604 		return true;
4605 
4606 	/*
4607 	 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
4608 	 * inherited the kernel context from early boot used to be skipped
4609 	 * here, so preserve that behavior unless the capability is set.
4610 	 *
4611 	 * By setting the capability the policy signals that it is ready
4612 	 * for this quirk to be fixed. Note that sockets created by a kernel
4613 	 * thread or a usermode helper executed without a transition will
4614 	 * still be skipped in this check regardless of the policycap
4615 	 * setting.
4616 	 */
4617 	if (!selinux_policycap_userspace_initial_context() &&
4618 	    sid == SECINITSID_INIT)
4619 		return true;
4620 	return false;
4621 }
4622 
4623 
sock_has_perm(struct sock * sk,u32 perms)4624 static int sock_has_perm(struct sock *sk, u32 perms)
4625 {
4626 	struct sk_security_struct *sksec = sk->sk_security;
4627 	struct common_audit_data ad;
4628 	struct lsm_network_audit net;
4629 
4630 	if (sock_skip_has_perm(sksec->sid))
4631 		return 0;
4632 
4633 	ad_net_init_from_sk(&ad, &net, sk);
4634 
4635 	return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
4636 			    &ad);
4637 }
4638 
selinux_socket_create(int family,int type,int protocol,int kern)4639 static int selinux_socket_create(int family, int type,
4640 				 int protocol, int kern)
4641 {
4642 	const struct task_security_struct *tsec = selinux_cred(current_cred());
4643 	u32 newsid;
4644 	u16 secclass;
4645 	int rc;
4646 
4647 	if (kern)
4648 		return 0;
4649 
4650 	secclass = socket_type_to_security_class(family, type, protocol);
4651 	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4652 	if (rc)
4653 		return rc;
4654 
4655 	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4656 }
4657 
selinux_socket_post_create(struct socket * sock,int family,int type,int protocol,int kern)4658 static int selinux_socket_post_create(struct socket *sock, int family,
4659 				      int type, int protocol, int kern)
4660 {
4661 	const struct task_security_struct *tsec = selinux_cred(current_cred());
4662 	struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4663 	struct sk_security_struct *sksec;
4664 	u16 sclass = socket_type_to_security_class(family, type, protocol);
4665 	u32 sid = SECINITSID_KERNEL;
4666 	int err = 0;
4667 
4668 	if (!kern) {
4669 		err = socket_sockcreate_sid(tsec, sclass, &sid);
4670 		if (err)
4671 			return err;
4672 	}
4673 
4674 	isec->sclass = sclass;
4675 	isec->sid = sid;
4676 	isec->initialized = LABEL_INITIALIZED;
4677 
4678 	if (sock->sk) {
4679 		sksec = selinux_sock(sock->sk);
4680 		sksec->sclass = sclass;
4681 		sksec->sid = sid;
4682 		/* Allows detection of the first association on this socket */
4683 		if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4684 			sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4685 
4686 		err = selinux_netlbl_socket_post_create(sock->sk, family);
4687 	}
4688 
4689 	return err;
4690 }
4691 
selinux_socket_socketpair(struct socket * socka,struct socket * sockb)4692 static int selinux_socket_socketpair(struct socket *socka,
4693 				     struct socket *sockb)
4694 {
4695 	struct sk_security_struct *sksec_a = selinux_sock(socka->sk);
4696 	struct sk_security_struct *sksec_b = selinux_sock(sockb->sk);
4697 
4698 	sksec_a->peer_sid = sksec_b->sid;
4699 	sksec_b->peer_sid = sksec_a->sid;
4700 
4701 	return 0;
4702 }
4703 
4704 /* Range of port numbers used to automatically bind.
4705    Need to determine whether we should perform a name_bind
4706    permission check between the socket and the port number. */
4707 
selinux_socket_bind(struct socket * sock,struct sockaddr * address,int addrlen)4708 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4709 {
4710 	struct sock *sk = sock->sk;
4711 	struct sk_security_struct *sksec = selinux_sock(sk);
4712 	u16 family;
4713 	int err;
4714 
4715 	err = sock_has_perm(sk, SOCKET__BIND);
4716 	if (err)
4717 		goto out;
4718 
4719 	/* If PF_INET or PF_INET6, check name_bind permission for the port. */
4720 	family = sk->sk_family;
4721 	if (family == PF_INET || family == PF_INET6) {
4722 		char *addrp;
4723 		struct common_audit_data ad;
4724 		struct lsm_network_audit net = {0,};
4725 		struct sockaddr_in *addr4 = NULL;
4726 		struct sockaddr_in6 *addr6 = NULL;
4727 		u16 family_sa;
4728 		unsigned short snum;
4729 		u32 sid, node_perm;
4730 
4731 		/*
4732 		 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4733 		 * that validates multiple binding addresses. Because of this
4734 		 * need to check address->sa_family as it is possible to have
4735 		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4736 		 */
4737 		if (addrlen < offsetofend(struct sockaddr, sa_family))
4738 			return -EINVAL;
4739 		family_sa = address->sa_family;
4740 		switch (family_sa) {
4741 		case AF_UNSPEC:
4742 		case AF_INET:
4743 			if (addrlen < sizeof(struct sockaddr_in))
4744 				return -EINVAL;
4745 			addr4 = (struct sockaddr_in *)address;
4746 			if (family_sa == AF_UNSPEC) {
4747 				if (family == PF_INET6) {
4748 					/* Length check from inet6_bind_sk() */
4749 					if (addrlen < SIN6_LEN_RFC2133)
4750 						return -EINVAL;
4751 					/* Family check from __inet6_bind() */
4752 					goto err_af;
4753 				}
4754 				/* see __inet_bind(), we only want to allow
4755 				 * AF_UNSPEC if the address is INADDR_ANY
4756 				 */
4757 				if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4758 					goto err_af;
4759 				family_sa = AF_INET;
4760 			}
4761 			snum = ntohs(addr4->sin_port);
4762 			addrp = (char *)&addr4->sin_addr.s_addr;
4763 			break;
4764 		case AF_INET6:
4765 			if (addrlen < SIN6_LEN_RFC2133)
4766 				return -EINVAL;
4767 			addr6 = (struct sockaddr_in6 *)address;
4768 			snum = ntohs(addr6->sin6_port);
4769 			addrp = (char *)&addr6->sin6_addr.s6_addr;
4770 			break;
4771 		default:
4772 			goto err_af;
4773 		}
4774 
4775 		ad.type = LSM_AUDIT_DATA_NET;
4776 		ad.u.net = &net;
4777 		ad.u.net->sport = htons(snum);
4778 		ad.u.net->family = family_sa;
4779 
4780 		if (snum) {
4781 			int low, high;
4782 
4783 			inet_get_local_port_range(sock_net(sk), &low, &high);
4784 
4785 			if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4786 			    snum < low || snum > high) {
4787 				err = sel_netport_sid(sk->sk_protocol,
4788 						      snum, &sid);
4789 				if (err)
4790 					goto out;
4791 				err = avc_has_perm(sksec->sid, sid,
4792 						   sksec->sclass,
4793 						   SOCKET__NAME_BIND, &ad);
4794 				if (err)
4795 					goto out;
4796 			}
4797 		}
4798 
4799 		switch (sksec->sclass) {
4800 		case SECCLASS_TCP_SOCKET:
4801 			node_perm = TCP_SOCKET__NODE_BIND;
4802 			break;
4803 
4804 		case SECCLASS_UDP_SOCKET:
4805 			node_perm = UDP_SOCKET__NODE_BIND;
4806 			break;
4807 
4808 		case SECCLASS_DCCP_SOCKET:
4809 			node_perm = DCCP_SOCKET__NODE_BIND;
4810 			break;
4811 
4812 		case SECCLASS_SCTP_SOCKET:
4813 			node_perm = SCTP_SOCKET__NODE_BIND;
4814 			break;
4815 
4816 		default:
4817 			node_perm = RAWIP_SOCKET__NODE_BIND;
4818 			break;
4819 		}
4820 
4821 		err = sel_netnode_sid(addrp, family_sa, &sid);
4822 		if (err)
4823 			goto out;
4824 
4825 		if (family_sa == AF_INET)
4826 			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4827 		else
4828 			ad.u.net->v6info.saddr = addr6->sin6_addr;
4829 
4830 		err = avc_has_perm(sksec->sid, sid,
4831 				   sksec->sclass, node_perm, &ad);
4832 		if (err)
4833 			goto out;
4834 	}
4835 out:
4836 	return err;
4837 err_af:
4838 	/* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4839 	if (sk->sk_protocol == IPPROTO_SCTP)
4840 		return -EINVAL;
4841 	return -EAFNOSUPPORT;
4842 }
4843 
4844 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4845  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4846  */
selinux_socket_connect_helper(struct socket * sock,struct sockaddr * address,int addrlen)4847 static int selinux_socket_connect_helper(struct socket *sock,
4848 					 struct sockaddr *address, int addrlen)
4849 {
4850 	struct sock *sk = sock->sk;
4851 	struct sk_security_struct *sksec = selinux_sock(sk);
4852 	int err;
4853 
4854 	err = sock_has_perm(sk, SOCKET__CONNECT);
4855 	if (err)
4856 		return err;
4857 	if (addrlen < offsetofend(struct sockaddr, sa_family))
4858 		return -EINVAL;
4859 
4860 	/* connect(AF_UNSPEC) has special handling, as it is a documented
4861 	 * way to disconnect the socket
4862 	 */
4863 	if (address->sa_family == AF_UNSPEC)
4864 		return 0;
4865 
4866 	/*
4867 	 * If a TCP, DCCP or SCTP socket, check name_connect permission
4868 	 * for the port.
4869 	 */
4870 	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4871 	    sksec->sclass == SECCLASS_DCCP_SOCKET ||
4872 	    sksec->sclass == SECCLASS_SCTP_SOCKET) {
4873 		struct common_audit_data ad;
4874 		struct lsm_network_audit net = {0,};
4875 		struct sockaddr_in *addr4 = NULL;
4876 		struct sockaddr_in6 *addr6 = NULL;
4877 		unsigned short snum;
4878 		u32 sid, perm;
4879 
4880 		/* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4881 		 * that validates multiple connect addresses. Because of this
4882 		 * need to check address->sa_family as it is possible to have
4883 		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4884 		 */
4885 		switch (address->sa_family) {
4886 		case AF_INET:
4887 			addr4 = (struct sockaddr_in *)address;
4888 			if (addrlen < sizeof(struct sockaddr_in))
4889 				return -EINVAL;
4890 			snum = ntohs(addr4->sin_port);
4891 			break;
4892 		case AF_INET6:
4893 			addr6 = (struct sockaddr_in6 *)address;
4894 			if (addrlen < SIN6_LEN_RFC2133)
4895 				return -EINVAL;
4896 			snum = ntohs(addr6->sin6_port);
4897 			break;
4898 		default:
4899 			/* Note that SCTP services expect -EINVAL, whereas
4900 			 * others expect -EAFNOSUPPORT.
4901 			 */
4902 			if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4903 				return -EINVAL;
4904 			else
4905 				return -EAFNOSUPPORT;
4906 		}
4907 
4908 		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4909 		if (err)
4910 			return err;
4911 
4912 		switch (sksec->sclass) {
4913 		case SECCLASS_TCP_SOCKET:
4914 			perm = TCP_SOCKET__NAME_CONNECT;
4915 			break;
4916 		case SECCLASS_DCCP_SOCKET:
4917 			perm = DCCP_SOCKET__NAME_CONNECT;
4918 			break;
4919 		case SECCLASS_SCTP_SOCKET:
4920 			perm = SCTP_SOCKET__NAME_CONNECT;
4921 			break;
4922 		}
4923 
4924 		ad.type = LSM_AUDIT_DATA_NET;
4925 		ad.u.net = &net;
4926 		ad.u.net->dport = htons(snum);
4927 		ad.u.net->family = address->sa_family;
4928 		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4929 		if (err)
4930 			return err;
4931 	}
4932 
4933 	return 0;
4934 }
4935 
4936 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
selinux_socket_connect(struct socket * sock,struct sockaddr * address,int addrlen)4937 static int selinux_socket_connect(struct socket *sock,
4938 				  struct sockaddr *address, int addrlen)
4939 {
4940 	int err;
4941 	struct sock *sk = sock->sk;
4942 
4943 	err = selinux_socket_connect_helper(sock, address, addrlen);
4944 	if (err)
4945 		return err;
4946 
4947 	return selinux_netlbl_socket_connect(sk, address);
4948 }
4949 
selinux_socket_listen(struct socket * sock,int backlog)4950 static int selinux_socket_listen(struct socket *sock, int backlog)
4951 {
4952 	return sock_has_perm(sock->sk, SOCKET__LISTEN);
4953 }
4954 
selinux_socket_accept(struct socket * sock,struct socket * newsock)4955 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4956 {
4957 	int err;
4958 	struct inode_security_struct *isec;
4959 	struct inode_security_struct *newisec;
4960 	u16 sclass;
4961 	u32 sid;
4962 
4963 	err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4964 	if (err)
4965 		return err;
4966 
4967 	isec = inode_security_novalidate(SOCK_INODE(sock));
4968 	spin_lock(&isec->lock);
4969 	sclass = isec->sclass;
4970 	sid = isec->sid;
4971 	spin_unlock(&isec->lock);
4972 
4973 	newisec = inode_security_novalidate(SOCK_INODE(newsock));
4974 	newisec->sclass = sclass;
4975 	newisec->sid = sid;
4976 	newisec->initialized = LABEL_INITIALIZED;
4977 
4978 	return 0;
4979 }
4980 
selinux_socket_sendmsg(struct socket * sock,struct msghdr * msg,int size)4981 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4982 				  int size)
4983 {
4984 	return sock_has_perm(sock->sk, SOCKET__WRITE);
4985 }
4986 
selinux_socket_recvmsg(struct socket * sock,struct msghdr * msg,int size,int flags)4987 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4988 				  int size, int flags)
4989 {
4990 	return sock_has_perm(sock->sk, SOCKET__READ);
4991 }
4992 
selinux_socket_getsockname(struct socket * sock)4993 static int selinux_socket_getsockname(struct socket *sock)
4994 {
4995 	return sock_has_perm(sock->sk, SOCKET__GETATTR);
4996 }
4997 
selinux_socket_getpeername(struct socket * sock)4998 static int selinux_socket_getpeername(struct socket *sock)
4999 {
5000 	return sock_has_perm(sock->sk, SOCKET__GETATTR);
5001 }
5002 
selinux_socket_setsockopt(struct socket * sock,int level,int optname)5003 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
5004 {
5005 	int err;
5006 
5007 	err = sock_has_perm(sock->sk, SOCKET__SETOPT);
5008 	if (err)
5009 		return err;
5010 
5011 	return selinux_netlbl_socket_setsockopt(sock, level, optname);
5012 }
5013 
selinux_socket_getsockopt(struct socket * sock,int level,int optname)5014 static int selinux_socket_getsockopt(struct socket *sock, int level,
5015 				     int optname)
5016 {
5017 	return sock_has_perm(sock->sk, SOCKET__GETOPT);
5018 }
5019 
selinux_socket_shutdown(struct socket * sock,int how)5020 static int selinux_socket_shutdown(struct socket *sock, int how)
5021 {
5022 	return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
5023 }
5024 
selinux_socket_unix_stream_connect(struct sock * sock,struct sock * other,struct sock * newsk)5025 static int selinux_socket_unix_stream_connect(struct sock *sock,
5026 					      struct sock *other,
5027 					      struct sock *newsk)
5028 {
5029 	struct sk_security_struct *sksec_sock = selinux_sock(sock);
5030 	struct sk_security_struct *sksec_other = selinux_sock(other);
5031 	struct sk_security_struct *sksec_new = selinux_sock(newsk);
5032 	struct common_audit_data ad;
5033 	struct lsm_network_audit net;
5034 	int err;
5035 
5036 	ad_net_init_from_sk(&ad, &net, other);
5037 
5038 	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
5039 			   sksec_other->sclass,
5040 			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5041 	if (err)
5042 		return err;
5043 
5044 	/* server child socket */
5045 	sksec_new->peer_sid = sksec_sock->sid;
5046 	err = security_sid_mls_copy(sksec_other->sid,
5047 				    sksec_sock->sid, &sksec_new->sid);
5048 	if (err)
5049 		return err;
5050 
5051 	/* connecting socket */
5052 	sksec_sock->peer_sid = sksec_new->sid;
5053 
5054 	return 0;
5055 }
5056 
selinux_socket_unix_may_send(struct socket * sock,struct socket * other)5057 static int selinux_socket_unix_may_send(struct socket *sock,
5058 					struct socket *other)
5059 {
5060 	struct sk_security_struct *ssec = selinux_sock(sock->sk);
5061 	struct sk_security_struct *osec = selinux_sock(other->sk);
5062 	struct common_audit_data ad;
5063 	struct lsm_network_audit net;
5064 
5065 	ad_net_init_from_sk(&ad, &net, other->sk);
5066 
5067 	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5068 			    &ad);
5069 }
5070 
selinux_inet_sys_rcv_skb(struct net * ns,int ifindex,char * addrp,u16 family,u32 peer_sid,struct common_audit_data * ad)5071 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5072 				    char *addrp, u16 family, u32 peer_sid,
5073 				    struct common_audit_data *ad)
5074 {
5075 	int err;
5076 	u32 if_sid;
5077 	u32 node_sid;
5078 
5079 	err = sel_netif_sid(ns, ifindex, &if_sid);
5080 	if (err)
5081 		return err;
5082 	err = avc_has_perm(peer_sid, if_sid,
5083 			   SECCLASS_NETIF, NETIF__INGRESS, ad);
5084 	if (err)
5085 		return err;
5086 
5087 	err = sel_netnode_sid(addrp, family, &node_sid);
5088 	if (err)
5089 		return err;
5090 	return avc_has_perm(peer_sid, node_sid,
5091 			    SECCLASS_NODE, NODE__RECVFROM, ad);
5092 }
5093 
selinux_sock_rcv_skb_compat(struct sock * sk,struct sk_buff * skb,u16 family)5094 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5095 				       u16 family)
5096 {
5097 	int err = 0;
5098 	struct sk_security_struct *sksec = selinux_sock(sk);
5099 	u32 sk_sid = sksec->sid;
5100 	struct common_audit_data ad;
5101 	struct lsm_network_audit net;
5102 	char *addrp;
5103 
5104 	ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5105 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5106 	if (err)
5107 		return err;
5108 
5109 	if (selinux_secmark_enabled()) {
5110 		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5111 				   PACKET__RECV, &ad);
5112 		if (err)
5113 			return err;
5114 	}
5115 
5116 	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5117 	if (err)
5118 		return err;
5119 	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5120 
5121 	return err;
5122 }
5123 
selinux_socket_sock_rcv_skb(struct sock * sk,struct sk_buff * skb)5124 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5125 {
5126 	int err, peerlbl_active, secmark_active;
5127 	struct sk_security_struct *sksec = selinux_sock(sk);
5128 	u16 family = sk->sk_family;
5129 	u32 sk_sid = sksec->sid;
5130 	struct common_audit_data ad;
5131 	struct lsm_network_audit net;
5132 	char *addrp;
5133 
5134 	if (family != PF_INET && family != PF_INET6)
5135 		return 0;
5136 
5137 	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
5138 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5139 		family = PF_INET;
5140 
5141 	/* If any sort of compatibility mode is enabled then handoff processing
5142 	 * to the selinux_sock_rcv_skb_compat() function to deal with the
5143 	 * special handling.  We do this in an attempt to keep this function
5144 	 * as fast and as clean as possible. */
5145 	if (!selinux_policycap_netpeer())
5146 		return selinux_sock_rcv_skb_compat(sk, skb, family);
5147 
5148 	secmark_active = selinux_secmark_enabled();
5149 	peerlbl_active = selinux_peerlbl_enabled();
5150 	if (!secmark_active && !peerlbl_active)
5151 		return 0;
5152 
5153 	ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5154 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5155 	if (err)
5156 		return err;
5157 
5158 	if (peerlbl_active) {
5159 		u32 peer_sid;
5160 
5161 		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5162 		if (err)
5163 			return err;
5164 		err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5165 					       addrp, family, peer_sid, &ad);
5166 		if (err) {
5167 			selinux_netlbl_err(skb, family, err, 0);
5168 			return err;
5169 		}
5170 		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
5171 				   PEER__RECV, &ad);
5172 		if (err) {
5173 			selinux_netlbl_err(skb, family, err, 0);
5174 			return err;
5175 		}
5176 	}
5177 
5178 	if (secmark_active) {
5179 		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5180 				   PACKET__RECV, &ad);
5181 		if (err)
5182 			return err;
5183 	}
5184 
5185 	return err;
5186 }
5187 
selinux_socket_getpeersec_stream(struct socket * sock,sockptr_t optval,sockptr_t optlen,unsigned int len)5188 static int selinux_socket_getpeersec_stream(struct socket *sock,
5189 					    sockptr_t optval, sockptr_t optlen,
5190 					    unsigned int len)
5191 {
5192 	int err = 0;
5193 	char *scontext = NULL;
5194 	u32 scontext_len;
5195 	struct sk_security_struct *sksec = selinux_sock(sock->sk);
5196 	u32 peer_sid = SECSID_NULL;
5197 
5198 	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5199 	    sksec->sclass == SECCLASS_TCP_SOCKET ||
5200 	    sksec->sclass == SECCLASS_SCTP_SOCKET)
5201 		peer_sid = sksec->peer_sid;
5202 	if (peer_sid == SECSID_NULL)
5203 		return -ENOPROTOOPT;
5204 
5205 	err = security_sid_to_context(peer_sid, &scontext,
5206 				      &scontext_len);
5207 	if (err)
5208 		return err;
5209 	if (scontext_len > len) {
5210 		err = -ERANGE;
5211 		goto out_len;
5212 	}
5213 
5214 	if (copy_to_sockptr(optval, scontext, scontext_len))
5215 		err = -EFAULT;
5216 out_len:
5217 	if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5218 		err = -EFAULT;
5219 	kfree(scontext);
5220 	return err;
5221 }
5222 
selinux_socket_getpeersec_dgram(struct socket * sock,struct sk_buff * skb,u32 * secid)5223 static int selinux_socket_getpeersec_dgram(struct socket *sock,
5224 					   struct sk_buff *skb, u32 *secid)
5225 {
5226 	u32 peer_secid = SECSID_NULL;
5227 	u16 family;
5228 
5229 	if (skb && skb->protocol == htons(ETH_P_IP))
5230 		family = PF_INET;
5231 	else if (skb && skb->protocol == htons(ETH_P_IPV6))
5232 		family = PF_INET6;
5233 	else if (sock)
5234 		family = sock->sk->sk_family;
5235 	else {
5236 		*secid = SECSID_NULL;
5237 		return -EINVAL;
5238 	}
5239 
5240 	if (sock && family == PF_UNIX) {
5241 		struct inode_security_struct *isec;
5242 		isec = inode_security_novalidate(SOCK_INODE(sock));
5243 		peer_secid = isec->sid;
5244 	} else if (skb)
5245 		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5246 
5247 	*secid = peer_secid;
5248 	if (peer_secid == SECSID_NULL)
5249 		return -ENOPROTOOPT;
5250 	return 0;
5251 }
5252 
selinux_sk_alloc_security(struct sock * sk,int family,gfp_t priority)5253 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5254 {
5255 	struct sk_security_struct *sksec = selinux_sock(sk);
5256 
5257 	sksec->peer_sid = SECINITSID_UNLABELED;
5258 	sksec->sid = SECINITSID_UNLABELED;
5259 	sksec->sclass = SECCLASS_SOCKET;
5260 	selinux_netlbl_sk_security_reset(sksec);
5261 
5262 	return 0;
5263 }
5264 
selinux_sk_free_security(struct sock * sk)5265 static void selinux_sk_free_security(struct sock *sk)
5266 {
5267 	struct sk_security_struct *sksec = selinux_sock(sk);
5268 
5269 	selinux_netlbl_sk_security_free(sksec);
5270 }
5271 
selinux_sk_clone_security(const struct sock * sk,struct sock * newsk)5272 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5273 {
5274 	struct sk_security_struct *sksec = selinux_sock(sk);
5275 	struct sk_security_struct *newsksec = selinux_sock(newsk);
5276 
5277 	newsksec->sid = sksec->sid;
5278 	newsksec->peer_sid = sksec->peer_sid;
5279 	newsksec->sclass = sksec->sclass;
5280 
5281 	selinux_netlbl_sk_security_reset(newsksec);
5282 }
5283 
selinux_sk_getsecid(const struct sock * sk,u32 * secid)5284 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid)
5285 {
5286 	if (!sk)
5287 		*secid = SECINITSID_ANY_SOCKET;
5288 	else {
5289 		const struct sk_security_struct *sksec = selinux_sock(sk);
5290 
5291 		*secid = sksec->sid;
5292 	}
5293 }
5294 
selinux_sock_graft(struct sock * sk,struct socket * parent)5295 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5296 {
5297 	struct inode_security_struct *isec =
5298 		inode_security_novalidate(SOCK_INODE(parent));
5299 	struct sk_security_struct *sksec = selinux_sock(sk);
5300 
5301 	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5302 	    sk->sk_family == PF_UNIX)
5303 		isec->sid = sksec->sid;
5304 	sksec->sclass = isec->sclass;
5305 }
5306 
5307 /*
5308  * Determines peer_secid for the asoc and updates socket's peer label
5309  * if it's the first association on the socket.
5310  */
selinux_sctp_process_new_assoc(struct sctp_association * asoc,struct sk_buff * skb)5311 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5312 					  struct sk_buff *skb)
5313 {
5314 	struct sock *sk = asoc->base.sk;
5315 	u16 family = sk->sk_family;
5316 	struct sk_security_struct *sksec = selinux_sock(sk);
5317 	struct common_audit_data ad;
5318 	struct lsm_network_audit net;
5319 	int err;
5320 
5321 	/* handle mapped IPv4 packets arriving via IPv6 sockets */
5322 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5323 		family = PF_INET;
5324 
5325 	if (selinux_peerlbl_enabled()) {
5326 		asoc->peer_secid = SECSID_NULL;
5327 
5328 		/* This will return peer_sid = SECSID_NULL if there are
5329 		 * no peer labels, see security_net_peersid_resolve().
5330 		 */
5331 		err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5332 		if (err)
5333 			return err;
5334 
5335 		if (asoc->peer_secid == SECSID_NULL)
5336 			asoc->peer_secid = SECINITSID_UNLABELED;
5337 	} else {
5338 		asoc->peer_secid = SECINITSID_UNLABELED;
5339 	}
5340 
5341 	if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5342 		sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5343 
5344 		/* Here as first association on socket. As the peer SID
5345 		 * was allowed by peer recv (and the netif/node checks),
5346 		 * then it is approved by policy and used as the primary
5347 		 * peer SID for getpeercon(3).
5348 		 */
5349 		sksec->peer_sid = asoc->peer_secid;
5350 	} else if (sksec->peer_sid != asoc->peer_secid) {
5351 		/* Other association peer SIDs are checked to enforce
5352 		 * consistency among the peer SIDs.
5353 		 */
5354 		ad_net_init_from_sk(&ad, &net, asoc->base.sk);
5355 		err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5356 				   sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5357 				   &ad);
5358 		if (err)
5359 			return err;
5360 	}
5361 	return 0;
5362 }
5363 
5364 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5365  * happens on an incoming connect(2), sctp_connectx(3) or
5366  * sctp_sendmsg(3) (with no association already present).
5367  */
selinux_sctp_assoc_request(struct sctp_association * asoc,struct sk_buff * skb)5368 static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5369 				      struct sk_buff *skb)
5370 {
5371 	struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5372 	u32 conn_sid;
5373 	int err;
5374 
5375 	if (!selinux_policycap_extsockclass())
5376 		return 0;
5377 
5378 	err = selinux_sctp_process_new_assoc(asoc, skb);
5379 	if (err)
5380 		return err;
5381 
5382 	/* Compute the MLS component for the connection and store
5383 	 * the information in asoc. This will be used by SCTP TCP type
5384 	 * sockets and peeled off connections as they cause a new
5385 	 * socket to be generated. selinux_sctp_sk_clone() will then
5386 	 * plug this into the new socket.
5387 	 */
5388 	err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5389 	if (err)
5390 		return err;
5391 
5392 	asoc->secid = conn_sid;
5393 
5394 	/* Set any NetLabel labels including CIPSO/CALIPSO options. */
5395 	return selinux_netlbl_sctp_assoc_request(asoc, skb);
5396 }
5397 
5398 /* Called when SCTP receives a COOKIE ACK chunk as the final
5399  * response to an association request (initited by us).
5400  */
selinux_sctp_assoc_established(struct sctp_association * asoc,struct sk_buff * skb)5401 static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5402 					  struct sk_buff *skb)
5403 {
5404 	struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5405 
5406 	if (!selinux_policycap_extsockclass())
5407 		return 0;
5408 
5409 	/* Inherit secid from the parent socket - this will be picked up
5410 	 * by selinux_sctp_sk_clone() if the association gets peeled off
5411 	 * into a new socket.
5412 	 */
5413 	asoc->secid = sksec->sid;
5414 
5415 	return selinux_sctp_process_new_assoc(asoc, skb);
5416 }
5417 
5418 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5419  * based on their @optname.
5420  */
selinux_sctp_bind_connect(struct sock * sk,int optname,struct sockaddr * address,int addrlen)5421 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5422 				     struct sockaddr *address,
5423 				     int addrlen)
5424 {
5425 	int len, err = 0, walk_size = 0;
5426 	void *addr_buf;
5427 	struct sockaddr *addr;
5428 	struct socket *sock;
5429 
5430 	if (!selinux_policycap_extsockclass())
5431 		return 0;
5432 
5433 	/* Process one or more addresses that may be IPv4 or IPv6 */
5434 	sock = sk->sk_socket;
5435 	addr_buf = address;
5436 
5437 	while (walk_size < addrlen) {
5438 		if (walk_size + sizeof(sa_family_t) > addrlen)
5439 			return -EINVAL;
5440 
5441 		addr = addr_buf;
5442 		switch (addr->sa_family) {
5443 		case AF_UNSPEC:
5444 		case AF_INET:
5445 			len = sizeof(struct sockaddr_in);
5446 			break;
5447 		case AF_INET6:
5448 			len = sizeof(struct sockaddr_in6);
5449 			break;
5450 		default:
5451 			return -EINVAL;
5452 		}
5453 
5454 		if (walk_size + len > addrlen)
5455 			return -EINVAL;
5456 
5457 		err = -EINVAL;
5458 		switch (optname) {
5459 		/* Bind checks */
5460 		case SCTP_PRIMARY_ADDR:
5461 		case SCTP_SET_PEER_PRIMARY_ADDR:
5462 		case SCTP_SOCKOPT_BINDX_ADD:
5463 			err = selinux_socket_bind(sock, addr, len);
5464 			break;
5465 		/* Connect checks */
5466 		case SCTP_SOCKOPT_CONNECTX:
5467 		case SCTP_PARAM_SET_PRIMARY:
5468 		case SCTP_PARAM_ADD_IP:
5469 		case SCTP_SENDMSG_CONNECT:
5470 			err = selinux_socket_connect_helper(sock, addr, len);
5471 			if (err)
5472 				return err;
5473 
5474 			/* As selinux_sctp_bind_connect() is called by the
5475 			 * SCTP protocol layer, the socket is already locked,
5476 			 * therefore selinux_netlbl_socket_connect_locked()
5477 			 * is called here. The situations handled are:
5478 			 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5479 			 * whenever a new IP address is added or when a new
5480 			 * primary address is selected.
5481 			 * Note that an SCTP connect(2) call happens before
5482 			 * the SCTP protocol layer and is handled via
5483 			 * selinux_socket_connect().
5484 			 */
5485 			err = selinux_netlbl_socket_connect_locked(sk, addr);
5486 			break;
5487 		}
5488 
5489 		if (err)
5490 			return err;
5491 
5492 		addr_buf += len;
5493 		walk_size += len;
5494 	}
5495 
5496 	return 0;
5497 }
5498 
5499 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
selinux_sctp_sk_clone(struct sctp_association * asoc,struct sock * sk,struct sock * newsk)5500 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5501 				  struct sock *newsk)
5502 {
5503 	struct sk_security_struct *sksec = selinux_sock(sk);
5504 	struct sk_security_struct *newsksec = selinux_sock(newsk);
5505 
5506 	/* If policy does not support SECCLASS_SCTP_SOCKET then call
5507 	 * the non-sctp clone version.
5508 	 */
5509 	if (!selinux_policycap_extsockclass())
5510 		return selinux_sk_clone_security(sk, newsk);
5511 
5512 	newsksec->sid = asoc->secid;
5513 	newsksec->peer_sid = asoc->peer_secid;
5514 	newsksec->sclass = sksec->sclass;
5515 	selinux_netlbl_sctp_sk_clone(sk, newsk);
5516 }
5517 
selinux_mptcp_add_subflow(struct sock * sk,struct sock * ssk)5518 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5519 {
5520 	struct sk_security_struct *ssksec = selinux_sock(ssk);
5521 	struct sk_security_struct *sksec = selinux_sock(sk);
5522 
5523 	ssksec->sclass = sksec->sclass;
5524 	ssksec->sid = sksec->sid;
5525 
5526 	/* replace the existing subflow label deleting the existing one
5527 	 * and re-recreating a new label using the updated context
5528 	 */
5529 	selinux_netlbl_sk_security_free(ssksec);
5530 	return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5531 }
5532 
selinux_inet_conn_request(const struct sock * sk,struct sk_buff * skb,struct request_sock * req)5533 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5534 				     struct request_sock *req)
5535 {
5536 	struct sk_security_struct *sksec = selinux_sock(sk);
5537 	int err;
5538 	u16 family = req->rsk_ops->family;
5539 	u32 connsid;
5540 	u32 peersid;
5541 
5542 	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5543 	if (err)
5544 		return err;
5545 	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5546 	if (err)
5547 		return err;
5548 	req->secid = connsid;
5549 	req->peer_secid = peersid;
5550 
5551 	return selinux_netlbl_inet_conn_request(req, family);
5552 }
5553 
selinux_inet_csk_clone(struct sock * newsk,const struct request_sock * req)5554 static void selinux_inet_csk_clone(struct sock *newsk,
5555 				   const struct request_sock *req)
5556 {
5557 	struct sk_security_struct *newsksec = selinux_sock(newsk);
5558 
5559 	newsksec->sid = req->secid;
5560 	newsksec->peer_sid = req->peer_secid;
5561 	/* NOTE: Ideally, we should also get the isec->sid for the
5562 	   new socket in sync, but we don't have the isec available yet.
5563 	   So we will wait until sock_graft to do it, by which
5564 	   time it will have been created and available. */
5565 
5566 	/* We don't need to take any sort of lock here as we are the only
5567 	 * thread with access to newsksec */
5568 	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5569 }
5570 
selinux_inet_conn_established(struct sock * sk,struct sk_buff * skb)5571 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5572 {
5573 	u16 family = sk->sk_family;
5574 	struct sk_security_struct *sksec = selinux_sock(sk);
5575 
5576 	/* handle mapped IPv4 packets arriving via IPv6 sockets */
5577 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5578 		family = PF_INET;
5579 
5580 	selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5581 }
5582 
selinux_secmark_relabel_packet(u32 sid)5583 static int selinux_secmark_relabel_packet(u32 sid)
5584 {
5585 	return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO,
5586 			    NULL);
5587 }
5588 
selinux_secmark_refcount_inc(void)5589 static void selinux_secmark_refcount_inc(void)
5590 {
5591 	atomic_inc(&selinux_secmark_refcount);
5592 }
5593 
selinux_secmark_refcount_dec(void)5594 static void selinux_secmark_refcount_dec(void)
5595 {
5596 	atomic_dec(&selinux_secmark_refcount);
5597 }
5598 
selinux_req_classify_flow(const struct request_sock * req,struct flowi_common * flic)5599 static void selinux_req_classify_flow(const struct request_sock *req,
5600 				      struct flowi_common *flic)
5601 {
5602 	flic->flowic_secid = req->secid;
5603 }
5604 
selinux_tun_dev_alloc_security(void * security)5605 static int selinux_tun_dev_alloc_security(void *security)
5606 {
5607 	struct tun_security_struct *tunsec = selinux_tun_dev(security);
5608 
5609 	tunsec->sid = current_sid();
5610 	return 0;
5611 }
5612 
selinux_tun_dev_create(void)5613 static int selinux_tun_dev_create(void)
5614 {
5615 	u32 sid = current_sid();
5616 
5617 	/* we aren't taking into account the "sockcreate" SID since the socket
5618 	 * that is being created here is not a socket in the traditional sense,
5619 	 * instead it is a private sock, accessible only to the kernel, and
5620 	 * representing a wide range of network traffic spanning multiple
5621 	 * connections unlike traditional sockets - check the TUN driver to
5622 	 * get a better understanding of why this socket is special */
5623 
5624 	return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5625 			    NULL);
5626 }
5627 
selinux_tun_dev_attach_queue(void * security)5628 static int selinux_tun_dev_attach_queue(void *security)
5629 {
5630 	struct tun_security_struct *tunsec = selinux_tun_dev(security);
5631 
5632 	return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5633 			    TUN_SOCKET__ATTACH_QUEUE, NULL);
5634 }
5635 
selinux_tun_dev_attach(struct sock * sk,void * security)5636 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5637 {
5638 	struct tun_security_struct *tunsec = selinux_tun_dev(security);
5639 	struct sk_security_struct *sksec = selinux_sock(sk);
5640 
5641 	/* we don't currently perform any NetLabel based labeling here and it
5642 	 * isn't clear that we would want to do so anyway; while we could apply
5643 	 * labeling without the support of the TUN user the resulting labeled
5644 	 * traffic from the other end of the connection would almost certainly
5645 	 * cause confusion to the TUN user that had no idea network labeling
5646 	 * protocols were being used */
5647 
5648 	sksec->sid = tunsec->sid;
5649 	sksec->sclass = SECCLASS_TUN_SOCKET;
5650 
5651 	return 0;
5652 }
5653 
selinux_tun_dev_open(void * security)5654 static int selinux_tun_dev_open(void *security)
5655 {
5656 	struct tun_security_struct *tunsec = selinux_tun_dev(security);
5657 	u32 sid = current_sid();
5658 	int err;
5659 
5660 	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5661 			   TUN_SOCKET__RELABELFROM, NULL);
5662 	if (err)
5663 		return err;
5664 	err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5665 			   TUN_SOCKET__RELABELTO, NULL);
5666 	if (err)
5667 		return err;
5668 	tunsec->sid = sid;
5669 
5670 	return 0;
5671 }
5672 
5673 #ifdef CONFIG_NETFILTER
5674 
selinux_ip_forward(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)5675 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5676 				       const struct nf_hook_state *state)
5677 {
5678 	int ifindex;
5679 	u16 family;
5680 	char *addrp;
5681 	u32 peer_sid;
5682 	struct common_audit_data ad;
5683 	struct lsm_network_audit net;
5684 	int secmark_active, peerlbl_active;
5685 
5686 	if (!selinux_policycap_netpeer())
5687 		return NF_ACCEPT;
5688 
5689 	secmark_active = selinux_secmark_enabled();
5690 	peerlbl_active = selinux_peerlbl_enabled();
5691 	if (!secmark_active && !peerlbl_active)
5692 		return NF_ACCEPT;
5693 
5694 	family = state->pf;
5695 	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5696 		return NF_DROP;
5697 
5698 	ifindex = state->in->ifindex;
5699 	ad_net_init_from_iif(&ad, &net, ifindex, family);
5700 	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5701 		return NF_DROP;
5702 
5703 	if (peerlbl_active) {
5704 		int err;
5705 
5706 		err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5707 					       addrp, family, peer_sid, &ad);
5708 		if (err) {
5709 			selinux_netlbl_err(skb, family, err, 1);
5710 			return NF_DROP;
5711 		}
5712 	}
5713 
5714 	if (secmark_active)
5715 		if (avc_has_perm(peer_sid, skb->secmark,
5716 				 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5717 			return NF_DROP;
5718 
5719 	if (netlbl_enabled())
5720 		/* we do this in the FORWARD path and not the POST_ROUTING
5721 		 * path because we want to make sure we apply the necessary
5722 		 * labeling before IPsec is applied so we can leverage AH
5723 		 * protection */
5724 		if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5725 			return NF_DROP;
5726 
5727 	return NF_ACCEPT;
5728 }
5729 
selinux_ip_output(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)5730 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5731 				      const struct nf_hook_state *state)
5732 {
5733 	struct sock *sk;
5734 	u32 sid;
5735 
5736 	if (!netlbl_enabled())
5737 		return NF_ACCEPT;
5738 
5739 	/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5740 	 * because we want to make sure we apply the necessary labeling
5741 	 * before IPsec is applied so we can leverage AH protection */
5742 	sk = sk_to_full_sk(skb->sk);
5743 	if (sk) {
5744 		struct sk_security_struct *sksec;
5745 
5746 		if (sk_listener(sk))
5747 			/* if the socket is the listening state then this
5748 			 * packet is a SYN-ACK packet which means it needs to
5749 			 * be labeled based on the connection/request_sock and
5750 			 * not the parent socket.  unfortunately, we can't
5751 			 * lookup the request_sock yet as it isn't queued on
5752 			 * the parent socket until after the SYN-ACK is sent.
5753 			 * the "solution" is to simply pass the packet as-is
5754 			 * as any IP option based labeling should be copied
5755 			 * from the initial connection request (in the IP
5756 			 * layer).  it is far from ideal, but until we get a
5757 			 * security label in the packet itself this is the
5758 			 * best we can do. */
5759 			return NF_ACCEPT;
5760 
5761 		/* standard practice, label using the parent socket */
5762 		sksec = selinux_sock(sk);
5763 		sid = sksec->sid;
5764 	} else
5765 		sid = SECINITSID_KERNEL;
5766 	if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5767 		return NF_DROP;
5768 
5769 	return NF_ACCEPT;
5770 }
5771 
5772 
selinux_ip_postroute_compat(struct sk_buff * skb,const struct nf_hook_state * state)5773 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5774 					const struct nf_hook_state *state)
5775 {
5776 	struct sock *sk;
5777 	struct sk_security_struct *sksec;
5778 	struct common_audit_data ad;
5779 	struct lsm_network_audit net;
5780 	u8 proto = 0;
5781 
5782 	sk = skb_to_full_sk(skb);
5783 	if (sk == NULL)
5784 		return NF_ACCEPT;
5785 	sksec = selinux_sock(sk);
5786 
5787 	ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf);
5788 	if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5789 		return NF_DROP;
5790 
5791 	if (selinux_secmark_enabled())
5792 		if (avc_has_perm(sksec->sid, skb->secmark,
5793 				 SECCLASS_PACKET, PACKET__SEND, &ad))
5794 			return NF_DROP_ERR(-ECONNREFUSED);
5795 
5796 	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5797 		return NF_DROP_ERR(-ECONNREFUSED);
5798 
5799 	return NF_ACCEPT;
5800 }
5801 
selinux_ip_postroute(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)5802 static unsigned int selinux_ip_postroute(void *priv,
5803 					 struct sk_buff *skb,
5804 					 const struct nf_hook_state *state)
5805 {
5806 	u16 family;
5807 	u32 secmark_perm;
5808 	u32 peer_sid;
5809 	int ifindex;
5810 	struct sock *sk;
5811 	struct common_audit_data ad;
5812 	struct lsm_network_audit net;
5813 	char *addrp;
5814 	int secmark_active, peerlbl_active;
5815 
5816 	/* If any sort of compatibility mode is enabled then handoff processing
5817 	 * to the selinux_ip_postroute_compat() function to deal with the
5818 	 * special handling.  We do this in an attempt to keep this function
5819 	 * as fast and as clean as possible. */
5820 	if (!selinux_policycap_netpeer())
5821 		return selinux_ip_postroute_compat(skb, state);
5822 
5823 	secmark_active = selinux_secmark_enabled();
5824 	peerlbl_active = selinux_peerlbl_enabled();
5825 	if (!secmark_active && !peerlbl_active)
5826 		return NF_ACCEPT;
5827 
5828 	sk = skb_to_full_sk(skb);
5829 
5830 #ifdef CONFIG_XFRM
5831 	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5832 	 * packet transformation so allow the packet to pass without any checks
5833 	 * since we'll have another chance to perform access control checks
5834 	 * when the packet is on it's final way out.
5835 	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5836 	 *       is NULL, in this case go ahead and apply access control.
5837 	 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5838 	 *       TCP listening state we cannot wait until the XFRM processing
5839 	 *       is done as we will miss out on the SA label if we do;
5840 	 *       unfortunately, this means more work, but it is only once per
5841 	 *       connection. */
5842 	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5843 	    !(sk && sk_listener(sk)))
5844 		return NF_ACCEPT;
5845 #endif
5846 
5847 	family = state->pf;
5848 	if (sk == NULL) {
5849 		/* Without an associated socket the packet is either coming
5850 		 * from the kernel or it is being forwarded; check the packet
5851 		 * to determine which and if the packet is being forwarded
5852 		 * query the packet directly to determine the security label. */
5853 		if (skb->skb_iif) {
5854 			secmark_perm = PACKET__FORWARD_OUT;
5855 			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5856 				return NF_DROP;
5857 		} else {
5858 			secmark_perm = PACKET__SEND;
5859 			peer_sid = SECINITSID_KERNEL;
5860 		}
5861 	} else if (sk_listener(sk)) {
5862 		/* Locally generated packet but the associated socket is in the
5863 		 * listening state which means this is a SYN-ACK packet.  In
5864 		 * this particular case the correct security label is assigned
5865 		 * to the connection/request_sock but unfortunately we can't
5866 		 * query the request_sock as it isn't queued on the parent
5867 		 * socket until after the SYN-ACK packet is sent; the only
5868 		 * viable choice is to regenerate the label like we do in
5869 		 * selinux_inet_conn_request().  See also selinux_ip_output()
5870 		 * for similar problems. */
5871 		u32 skb_sid;
5872 		struct sk_security_struct *sksec;
5873 
5874 		sksec = selinux_sock(sk);
5875 		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5876 			return NF_DROP;
5877 		/* At this point, if the returned skb peerlbl is SECSID_NULL
5878 		 * and the packet has been through at least one XFRM
5879 		 * transformation then we must be dealing with the "final"
5880 		 * form of labeled IPsec packet; since we've already applied
5881 		 * all of our access controls on this packet we can safely
5882 		 * pass the packet. */
5883 		if (skb_sid == SECSID_NULL) {
5884 			switch (family) {
5885 			case PF_INET:
5886 				if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5887 					return NF_ACCEPT;
5888 				break;
5889 			case PF_INET6:
5890 				if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5891 					return NF_ACCEPT;
5892 				break;
5893 			default:
5894 				return NF_DROP_ERR(-ECONNREFUSED);
5895 			}
5896 		}
5897 		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5898 			return NF_DROP;
5899 		secmark_perm = PACKET__SEND;
5900 	} else {
5901 		/* Locally generated packet, fetch the security label from the
5902 		 * associated socket. */
5903 		struct sk_security_struct *sksec = selinux_sock(sk);
5904 		peer_sid = sksec->sid;
5905 		secmark_perm = PACKET__SEND;
5906 	}
5907 
5908 	ifindex = state->out->ifindex;
5909 	ad_net_init_from_iif(&ad, &net, ifindex, family);
5910 	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5911 		return NF_DROP;
5912 
5913 	if (secmark_active)
5914 		if (avc_has_perm(peer_sid, skb->secmark,
5915 				 SECCLASS_PACKET, secmark_perm, &ad))
5916 			return NF_DROP_ERR(-ECONNREFUSED);
5917 
5918 	if (peerlbl_active) {
5919 		u32 if_sid;
5920 		u32 node_sid;
5921 
5922 		if (sel_netif_sid(state->net, ifindex, &if_sid))
5923 			return NF_DROP;
5924 		if (avc_has_perm(peer_sid, if_sid,
5925 				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5926 			return NF_DROP_ERR(-ECONNREFUSED);
5927 
5928 		if (sel_netnode_sid(addrp, family, &node_sid))
5929 			return NF_DROP;
5930 		if (avc_has_perm(peer_sid, node_sid,
5931 				 SECCLASS_NODE, NODE__SENDTO, &ad))
5932 			return NF_DROP_ERR(-ECONNREFUSED);
5933 	}
5934 
5935 	return NF_ACCEPT;
5936 }
5937 #endif	/* CONFIG_NETFILTER */
5938 
nlmsg_sock_has_extended_perms(struct sock * sk,u32 perms,u16 nlmsg_type)5939 static int nlmsg_sock_has_extended_perms(struct sock *sk, u32 perms, u16 nlmsg_type)
5940 {
5941 	struct sk_security_struct *sksec = sk->sk_security;
5942 	struct common_audit_data ad;
5943 	u8 driver;
5944 	u8 xperm;
5945 
5946 	if (sock_skip_has_perm(sksec->sid))
5947 		return 0;
5948 
5949 	ad.type = LSM_AUDIT_DATA_NLMSGTYPE;
5950 	ad.u.nlmsg_type = nlmsg_type;
5951 
5952 	driver = nlmsg_type >> 8;
5953 	xperm = nlmsg_type & 0xff;
5954 
5955 	return avc_has_extended_perms(current_sid(), sksec->sid, sksec->sclass,
5956 				      perms, driver, AVC_EXT_NLMSG, xperm, &ad);
5957 }
5958 
selinux_netlink_send(struct sock * sk,struct sk_buff * skb)5959 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5960 {
5961 	int rc = 0;
5962 	unsigned int msg_len;
5963 	unsigned int data_len = skb->len;
5964 	unsigned char *data = skb->data;
5965 	struct nlmsghdr *nlh;
5966 	struct sk_security_struct *sksec = selinux_sock(sk);
5967 	u16 sclass = sksec->sclass;
5968 	u32 perm;
5969 
5970 	while (data_len >= nlmsg_total_size(0)) {
5971 		nlh = (struct nlmsghdr *)data;
5972 
5973 		/* NOTE: the nlmsg_len field isn't reliably set by some netlink
5974 		 *       users which means we can't reject skb's with bogus
5975 		 *       length fields; our solution is to follow what
5976 		 *       netlink_rcv_skb() does and simply skip processing at
5977 		 *       messages with length fields that are clearly junk
5978 		 */
5979 		if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5980 			return 0;
5981 
5982 		rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5983 		if (rc == 0) {
5984 			if (selinux_policycap_netlink_xperm()) {
5985 				rc = nlmsg_sock_has_extended_perms(
5986 					sk, perm, nlh->nlmsg_type);
5987 			} else {
5988 				rc = sock_has_perm(sk, perm);
5989 			}
5990 			if (rc)
5991 				return rc;
5992 		} else if (rc == -EINVAL) {
5993 			/* -EINVAL is a missing msg/perm mapping */
5994 			pr_warn_ratelimited("SELinux: unrecognized netlink"
5995 				" message: protocol=%hu nlmsg_type=%hu sclass=%s"
5996 				" pid=%d comm=%s\n",
5997 				sk->sk_protocol, nlh->nlmsg_type,
5998 				secclass_map[sclass - 1].name,
5999 				task_pid_nr(current), current->comm);
6000 			if (enforcing_enabled() &&
6001 			    !security_get_allow_unknown())
6002 				return rc;
6003 			rc = 0;
6004 		} else if (rc == -ENOENT) {
6005 			/* -ENOENT is a missing socket/class mapping, ignore */
6006 			rc = 0;
6007 		} else {
6008 			return rc;
6009 		}
6010 
6011 		/* move to the next message after applying netlink padding */
6012 		msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
6013 		if (msg_len >= data_len)
6014 			return 0;
6015 		data_len -= msg_len;
6016 		data += msg_len;
6017 	}
6018 
6019 	return rc;
6020 }
6021 
ipc_init_security(struct ipc_security_struct * isec,u16 sclass)6022 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
6023 {
6024 	isec->sclass = sclass;
6025 	isec->sid = current_sid();
6026 }
6027 
ipc_has_perm(struct kern_ipc_perm * ipc_perms,u32 perms)6028 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
6029 			u32 perms)
6030 {
6031 	struct ipc_security_struct *isec;
6032 	struct common_audit_data ad;
6033 	u32 sid = current_sid();
6034 
6035 	isec = selinux_ipc(ipc_perms);
6036 
6037 	ad.type = LSM_AUDIT_DATA_IPC;
6038 	ad.u.ipc_id = ipc_perms->key;
6039 
6040 	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
6041 }
6042 
selinux_msg_msg_alloc_security(struct msg_msg * msg)6043 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6044 {
6045 	struct msg_security_struct *msec;
6046 
6047 	msec = selinux_msg_msg(msg);
6048 	msec->sid = SECINITSID_UNLABELED;
6049 
6050 	return 0;
6051 }
6052 
6053 /* message queue security operations */
selinux_msg_queue_alloc_security(struct kern_ipc_perm * msq)6054 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6055 {
6056 	struct ipc_security_struct *isec;
6057 	struct common_audit_data ad;
6058 	u32 sid = current_sid();
6059 
6060 	isec = selinux_ipc(msq);
6061 	ipc_init_security(isec, SECCLASS_MSGQ);
6062 
6063 	ad.type = LSM_AUDIT_DATA_IPC;
6064 	ad.u.ipc_id = msq->key;
6065 
6066 	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6067 			    MSGQ__CREATE, &ad);
6068 }
6069 
selinux_msg_queue_associate(struct kern_ipc_perm * msq,int msqflg)6070 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6071 {
6072 	struct ipc_security_struct *isec;
6073 	struct common_audit_data ad;
6074 	u32 sid = current_sid();
6075 
6076 	isec = selinux_ipc(msq);
6077 
6078 	ad.type = LSM_AUDIT_DATA_IPC;
6079 	ad.u.ipc_id = msq->key;
6080 
6081 	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6082 			    MSGQ__ASSOCIATE, &ad);
6083 }
6084 
selinux_msg_queue_msgctl(struct kern_ipc_perm * msq,int cmd)6085 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6086 {
6087 	u32 perms;
6088 
6089 	switch (cmd) {
6090 	case IPC_INFO:
6091 	case MSG_INFO:
6092 		/* No specific object, just general system-wide information. */
6093 		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6094 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6095 	case IPC_STAT:
6096 	case MSG_STAT:
6097 	case MSG_STAT_ANY:
6098 		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6099 		break;
6100 	case IPC_SET:
6101 		perms = MSGQ__SETATTR;
6102 		break;
6103 	case IPC_RMID:
6104 		perms = MSGQ__DESTROY;
6105 		break;
6106 	default:
6107 		return 0;
6108 	}
6109 
6110 	return ipc_has_perm(msq, perms);
6111 }
6112 
selinux_msg_queue_msgsnd(struct kern_ipc_perm * msq,struct msg_msg * msg,int msqflg)6113 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6114 {
6115 	struct ipc_security_struct *isec;
6116 	struct msg_security_struct *msec;
6117 	struct common_audit_data ad;
6118 	u32 sid = current_sid();
6119 	int rc;
6120 
6121 	isec = selinux_ipc(msq);
6122 	msec = selinux_msg_msg(msg);
6123 
6124 	/*
6125 	 * First time through, need to assign label to the message
6126 	 */
6127 	if (msec->sid == SECINITSID_UNLABELED) {
6128 		/*
6129 		 * Compute new sid based on current process and
6130 		 * message queue this message will be stored in
6131 		 */
6132 		rc = security_transition_sid(sid, isec->sid,
6133 					     SECCLASS_MSG, NULL, &msec->sid);
6134 		if (rc)
6135 			return rc;
6136 	}
6137 
6138 	ad.type = LSM_AUDIT_DATA_IPC;
6139 	ad.u.ipc_id = msq->key;
6140 
6141 	/* Can this process write to the queue? */
6142 	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6143 			  MSGQ__WRITE, &ad);
6144 	if (!rc)
6145 		/* Can this process send the message */
6146 		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
6147 				  MSG__SEND, &ad);
6148 	if (!rc)
6149 		/* Can the message be put in the queue? */
6150 		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
6151 				  MSGQ__ENQUEUE, &ad);
6152 
6153 	return rc;
6154 }
6155 
selinux_msg_queue_msgrcv(struct kern_ipc_perm * msq,struct msg_msg * msg,struct task_struct * target,long type,int mode)6156 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6157 				    struct task_struct *target,
6158 				    long type, int mode)
6159 {
6160 	struct ipc_security_struct *isec;
6161 	struct msg_security_struct *msec;
6162 	struct common_audit_data ad;
6163 	u32 sid = task_sid_obj(target);
6164 	int rc;
6165 
6166 	isec = selinux_ipc(msq);
6167 	msec = selinux_msg_msg(msg);
6168 
6169 	ad.type = LSM_AUDIT_DATA_IPC;
6170 	ad.u.ipc_id = msq->key;
6171 
6172 	rc = avc_has_perm(sid, isec->sid,
6173 			  SECCLASS_MSGQ, MSGQ__READ, &ad);
6174 	if (!rc)
6175 		rc = avc_has_perm(sid, msec->sid,
6176 				  SECCLASS_MSG, MSG__RECEIVE, &ad);
6177 	return rc;
6178 }
6179 
6180 /* Shared Memory security operations */
selinux_shm_alloc_security(struct kern_ipc_perm * shp)6181 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6182 {
6183 	struct ipc_security_struct *isec;
6184 	struct common_audit_data ad;
6185 	u32 sid = current_sid();
6186 
6187 	isec = selinux_ipc(shp);
6188 	ipc_init_security(isec, SECCLASS_SHM);
6189 
6190 	ad.type = LSM_AUDIT_DATA_IPC;
6191 	ad.u.ipc_id = shp->key;
6192 
6193 	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6194 			    SHM__CREATE, &ad);
6195 }
6196 
selinux_shm_associate(struct kern_ipc_perm * shp,int shmflg)6197 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6198 {
6199 	struct ipc_security_struct *isec;
6200 	struct common_audit_data ad;
6201 	u32 sid = current_sid();
6202 
6203 	isec = selinux_ipc(shp);
6204 
6205 	ad.type = LSM_AUDIT_DATA_IPC;
6206 	ad.u.ipc_id = shp->key;
6207 
6208 	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6209 			    SHM__ASSOCIATE, &ad);
6210 }
6211 
6212 /* Note, at this point, shp is locked down */
selinux_shm_shmctl(struct kern_ipc_perm * shp,int cmd)6213 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6214 {
6215 	u32 perms;
6216 
6217 	switch (cmd) {
6218 	case IPC_INFO:
6219 	case SHM_INFO:
6220 		/* No specific object, just general system-wide information. */
6221 		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6222 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6223 	case IPC_STAT:
6224 	case SHM_STAT:
6225 	case SHM_STAT_ANY:
6226 		perms = SHM__GETATTR | SHM__ASSOCIATE;
6227 		break;
6228 	case IPC_SET:
6229 		perms = SHM__SETATTR;
6230 		break;
6231 	case SHM_LOCK:
6232 	case SHM_UNLOCK:
6233 		perms = SHM__LOCK;
6234 		break;
6235 	case IPC_RMID:
6236 		perms = SHM__DESTROY;
6237 		break;
6238 	default:
6239 		return 0;
6240 	}
6241 
6242 	return ipc_has_perm(shp, perms);
6243 }
6244 
selinux_shm_shmat(struct kern_ipc_perm * shp,char __user * shmaddr,int shmflg)6245 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6246 			     char __user *shmaddr, int shmflg)
6247 {
6248 	u32 perms;
6249 
6250 	if (shmflg & SHM_RDONLY)
6251 		perms = SHM__READ;
6252 	else
6253 		perms = SHM__READ | SHM__WRITE;
6254 
6255 	return ipc_has_perm(shp, perms);
6256 }
6257 
6258 /* Semaphore security operations */
selinux_sem_alloc_security(struct kern_ipc_perm * sma)6259 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6260 {
6261 	struct ipc_security_struct *isec;
6262 	struct common_audit_data ad;
6263 	u32 sid = current_sid();
6264 
6265 	isec = selinux_ipc(sma);
6266 	ipc_init_security(isec, SECCLASS_SEM);
6267 
6268 	ad.type = LSM_AUDIT_DATA_IPC;
6269 	ad.u.ipc_id = sma->key;
6270 
6271 	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6272 			    SEM__CREATE, &ad);
6273 }
6274 
selinux_sem_associate(struct kern_ipc_perm * sma,int semflg)6275 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6276 {
6277 	struct ipc_security_struct *isec;
6278 	struct common_audit_data ad;
6279 	u32 sid = current_sid();
6280 
6281 	isec = selinux_ipc(sma);
6282 
6283 	ad.type = LSM_AUDIT_DATA_IPC;
6284 	ad.u.ipc_id = sma->key;
6285 
6286 	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6287 			    SEM__ASSOCIATE, &ad);
6288 }
6289 
6290 /* Note, at this point, sma is locked down */
selinux_sem_semctl(struct kern_ipc_perm * sma,int cmd)6291 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6292 {
6293 	int err;
6294 	u32 perms;
6295 
6296 	switch (cmd) {
6297 	case IPC_INFO:
6298 	case SEM_INFO:
6299 		/* No specific object, just general system-wide information. */
6300 		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6301 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6302 	case GETPID:
6303 	case GETNCNT:
6304 	case GETZCNT:
6305 		perms = SEM__GETATTR;
6306 		break;
6307 	case GETVAL:
6308 	case GETALL:
6309 		perms = SEM__READ;
6310 		break;
6311 	case SETVAL:
6312 	case SETALL:
6313 		perms = SEM__WRITE;
6314 		break;
6315 	case IPC_RMID:
6316 		perms = SEM__DESTROY;
6317 		break;
6318 	case IPC_SET:
6319 		perms = SEM__SETATTR;
6320 		break;
6321 	case IPC_STAT:
6322 	case SEM_STAT:
6323 	case SEM_STAT_ANY:
6324 		perms = SEM__GETATTR | SEM__ASSOCIATE;
6325 		break;
6326 	default:
6327 		return 0;
6328 	}
6329 
6330 	err = ipc_has_perm(sma, perms);
6331 	return err;
6332 }
6333 
selinux_sem_semop(struct kern_ipc_perm * sma,struct sembuf * sops,unsigned nsops,int alter)6334 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6335 			     struct sembuf *sops, unsigned nsops, int alter)
6336 {
6337 	u32 perms;
6338 
6339 	if (alter)
6340 		perms = SEM__READ | SEM__WRITE;
6341 	else
6342 		perms = SEM__READ;
6343 
6344 	return ipc_has_perm(sma, perms);
6345 }
6346 
selinux_ipc_permission(struct kern_ipc_perm * ipcp,short flag)6347 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6348 {
6349 	u32 av = 0;
6350 
6351 	av = 0;
6352 	if (flag & S_IRUGO)
6353 		av |= IPC__UNIX_READ;
6354 	if (flag & S_IWUGO)
6355 		av |= IPC__UNIX_WRITE;
6356 
6357 	if (av == 0)
6358 		return 0;
6359 
6360 	return ipc_has_perm(ipcp, av);
6361 }
6362 
selinux_ipc_getlsmprop(struct kern_ipc_perm * ipcp,struct lsm_prop * prop)6363 static void selinux_ipc_getlsmprop(struct kern_ipc_perm *ipcp,
6364 				   struct lsm_prop *prop)
6365 {
6366 	struct ipc_security_struct *isec = selinux_ipc(ipcp);
6367 	prop->selinux.secid = isec->sid;
6368 }
6369 
selinux_d_instantiate(struct dentry * dentry,struct inode * inode)6370 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6371 {
6372 	if (inode)
6373 		inode_doinit_with_dentry(inode, dentry);
6374 }
6375 
selinux_lsm_getattr(unsigned int attr,struct task_struct * p,char ** value)6376 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
6377 			       char **value)
6378 {
6379 	const struct task_security_struct *tsec;
6380 	int error;
6381 	u32 sid;
6382 	u32 len;
6383 
6384 	rcu_read_lock();
6385 	tsec = selinux_cred(__task_cred(p));
6386 	if (p != current) {
6387 		error = avc_has_perm(current_sid(), tsec->sid,
6388 				     SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6389 		if (error)
6390 			goto err_unlock;
6391 	}
6392 	switch (attr) {
6393 	case LSM_ATTR_CURRENT:
6394 		sid = tsec->sid;
6395 		break;
6396 	case LSM_ATTR_PREV:
6397 		sid = tsec->osid;
6398 		break;
6399 	case LSM_ATTR_EXEC:
6400 		sid = tsec->exec_sid;
6401 		break;
6402 	case LSM_ATTR_FSCREATE:
6403 		sid = tsec->create_sid;
6404 		break;
6405 	case LSM_ATTR_KEYCREATE:
6406 		sid = tsec->keycreate_sid;
6407 		break;
6408 	case LSM_ATTR_SOCKCREATE:
6409 		sid = tsec->sockcreate_sid;
6410 		break;
6411 	default:
6412 		error = -EOPNOTSUPP;
6413 		goto err_unlock;
6414 	}
6415 	rcu_read_unlock();
6416 
6417 	if (sid == SECSID_NULL) {
6418 		*value = NULL;
6419 		return 0;
6420 	}
6421 
6422 	error = security_sid_to_context(sid, value, &len);
6423 	if (error)
6424 		return error;
6425 	return len;
6426 
6427 err_unlock:
6428 	rcu_read_unlock();
6429 	return error;
6430 }
6431 
selinux_lsm_setattr(u64 attr,void * value,size_t size)6432 static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
6433 {
6434 	struct task_security_struct *tsec;
6435 	struct cred *new;
6436 	u32 mysid = current_sid(), sid = 0, ptsid;
6437 	int error;
6438 	char *str = value;
6439 
6440 	/*
6441 	 * Basic control over ability to set these attributes at all.
6442 	 */
6443 	switch (attr) {
6444 	case LSM_ATTR_EXEC:
6445 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6446 				     PROCESS__SETEXEC, NULL);
6447 		break;
6448 	case LSM_ATTR_FSCREATE:
6449 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6450 				     PROCESS__SETFSCREATE, NULL);
6451 		break;
6452 	case LSM_ATTR_KEYCREATE:
6453 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6454 				     PROCESS__SETKEYCREATE, NULL);
6455 		break;
6456 	case LSM_ATTR_SOCKCREATE:
6457 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6458 				     PROCESS__SETSOCKCREATE, NULL);
6459 		break;
6460 	case LSM_ATTR_CURRENT:
6461 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6462 				     PROCESS__SETCURRENT, NULL);
6463 		break;
6464 	default:
6465 		error = -EOPNOTSUPP;
6466 		break;
6467 	}
6468 	if (error)
6469 		return error;
6470 
6471 	/* Obtain a SID for the context, if one was specified. */
6472 	if (size && str[0] && str[0] != '\n') {
6473 		if (str[size-1] == '\n') {
6474 			str[size-1] = 0;
6475 			size--;
6476 		}
6477 		error = security_context_to_sid(value, size,
6478 						&sid, GFP_KERNEL);
6479 		if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
6480 			if (!has_cap_mac_admin(true)) {
6481 				struct audit_buffer *ab;
6482 				size_t audit_size;
6483 
6484 				/* We strip a nul only if it is at the end,
6485 				 * otherwise the context contains a nul and
6486 				 * we should audit that */
6487 				if (str[size - 1] == '\0')
6488 					audit_size = size - 1;
6489 				else
6490 					audit_size = size;
6491 				ab = audit_log_start(audit_context(),
6492 						     GFP_ATOMIC,
6493 						     AUDIT_SELINUX_ERR);
6494 				if (!ab)
6495 					return error;
6496 				audit_log_format(ab, "op=fscreate invalid_context=");
6497 				audit_log_n_untrustedstring(ab, value,
6498 							    audit_size);
6499 				audit_log_end(ab);
6500 
6501 				return error;
6502 			}
6503 			error = security_context_to_sid_force(value, size,
6504 							&sid);
6505 		}
6506 		if (error)
6507 			return error;
6508 	}
6509 
6510 	new = prepare_creds();
6511 	if (!new)
6512 		return -ENOMEM;
6513 
6514 	/* Permission checking based on the specified context is
6515 	   performed during the actual operation (execve,
6516 	   open/mkdir/...), when we know the full context of the
6517 	   operation.  See selinux_bprm_creds_for_exec for the execve
6518 	   checks and may_create for the file creation checks. The
6519 	   operation will then fail if the context is not permitted. */
6520 	tsec = selinux_cred(new);
6521 	if (attr == LSM_ATTR_EXEC) {
6522 		tsec->exec_sid = sid;
6523 	} else if (attr == LSM_ATTR_FSCREATE) {
6524 		tsec->create_sid = sid;
6525 	} else if (attr == LSM_ATTR_KEYCREATE) {
6526 		if (sid) {
6527 			error = avc_has_perm(mysid, sid,
6528 					     SECCLASS_KEY, KEY__CREATE, NULL);
6529 			if (error)
6530 				goto abort_change;
6531 		}
6532 		tsec->keycreate_sid = sid;
6533 	} else if (attr == LSM_ATTR_SOCKCREATE) {
6534 		tsec->sockcreate_sid = sid;
6535 	} else if (attr == LSM_ATTR_CURRENT) {
6536 		error = -EINVAL;
6537 		if (sid == 0)
6538 			goto abort_change;
6539 
6540 		if (!current_is_single_threaded()) {
6541 			error = security_bounded_transition(tsec->sid, sid);
6542 			if (error)
6543 				goto abort_change;
6544 		}
6545 
6546 		/* Check permissions for the transition. */
6547 		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6548 				     PROCESS__DYNTRANSITION, NULL);
6549 		if (error)
6550 			goto abort_change;
6551 
6552 		/* Check for ptracing, and update the task SID if ok.
6553 		   Otherwise, leave SID unchanged and fail. */
6554 		ptsid = ptrace_parent_sid();
6555 		if (ptsid != 0) {
6556 			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
6557 					     PROCESS__PTRACE, NULL);
6558 			if (error)
6559 				goto abort_change;
6560 		}
6561 
6562 		tsec->sid = sid;
6563 	} else {
6564 		error = -EINVAL;
6565 		goto abort_change;
6566 	}
6567 
6568 	commit_creds(new);
6569 	return size;
6570 
6571 abort_change:
6572 	abort_creds(new);
6573 	return error;
6574 }
6575 
6576 /**
6577  * selinux_getselfattr - Get SELinux current task attributes
6578  * @attr: the requested attribute
6579  * @ctx: buffer to receive the result
6580  * @size: buffer size (input), buffer size used (output)
6581  * @flags: unused
6582  *
6583  * Fill the passed user space @ctx with the details of the requested
6584  * attribute.
6585  *
6586  * Returns the number of attributes on success, an error code otherwise.
6587  * There will only ever be one attribute.
6588  */
selinux_getselfattr(unsigned int attr,struct lsm_ctx __user * ctx,u32 * size,u32 flags)6589 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
6590 			       u32 *size, u32 flags)
6591 {
6592 	int rc;
6593 	char *val = NULL;
6594 	int val_len;
6595 
6596 	val_len = selinux_lsm_getattr(attr, current, &val);
6597 	if (val_len < 0)
6598 		return val_len;
6599 	rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0);
6600 	kfree(val);
6601 	return (!rc ? 1 : rc);
6602 }
6603 
selinux_setselfattr(unsigned int attr,struct lsm_ctx * ctx,u32 size,u32 flags)6604 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
6605 			       u32 size, u32 flags)
6606 {
6607 	int rc;
6608 
6609 	rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len);
6610 	if (rc > 0)
6611 		return 0;
6612 	return rc;
6613 }
6614 
selinux_getprocattr(struct task_struct * p,const char * name,char ** value)6615 static int selinux_getprocattr(struct task_struct *p,
6616 			       const char *name, char **value)
6617 {
6618 	unsigned int attr = lsm_name_to_attr(name);
6619 	int rc;
6620 
6621 	if (attr) {
6622 		rc = selinux_lsm_getattr(attr, p, value);
6623 		if (rc != -EOPNOTSUPP)
6624 			return rc;
6625 	}
6626 
6627 	return -EINVAL;
6628 }
6629 
selinux_setprocattr(const char * name,void * value,size_t size)6630 static int selinux_setprocattr(const char *name, void *value, size_t size)
6631 {
6632 	int attr = lsm_name_to_attr(name);
6633 
6634 	if (attr)
6635 		return selinux_lsm_setattr(attr, value, size);
6636 	return -EINVAL;
6637 }
6638 
selinux_ismaclabel(const char * name)6639 static int selinux_ismaclabel(const char *name)
6640 {
6641 	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6642 }
6643 
selinux_secid_to_secctx(u32 secid,struct lsm_context * cp)6644 static int selinux_secid_to_secctx(u32 secid, struct lsm_context *cp)
6645 {
6646 	u32 seclen;
6647 	int ret;
6648 
6649 	if (cp) {
6650 		cp->id = LSM_ID_SELINUX;
6651 		ret = security_sid_to_context(secid, &cp->context, &cp->len);
6652 		if (ret < 0)
6653 			return ret;
6654 		return cp->len;
6655 	}
6656 	ret = security_sid_to_context(secid, NULL, &seclen);
6657 	if (ret < 0)
6658 		return ret;
6659 	return seclen;
6660 }
6661 
selinux_lsmprop_to_secctx(struct lsm_prop * prop,struct lsm_context * cp)6662 static int selinux_lsmprop_to_secctx(struct lsm_prop *prop,
6663 				     struct lsm_context *cp)
6664 {
6665 	return selinux_secid_to_secctx(prop->selinux.secid, cp);
6666 }
6667 
selinux_secctx_to_secid(const char * secdata,u32 seclen,u32 * secid)6668 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6669 {
6670 	return security_context_to_sid(secdata, seclen,
6671 				       secid, GFP_KERNEL);
6672 }
6673 
selinux_release_secctx(struct lsm_context * cp)6674 static void selinux_release_secctx(struct lsm_context *cp)
6675 {
6676 	if (cp->id == LSM_ID_SELINUX) {
6677 		kfree(cp->context);
6678 		cp->context = NULL;
6679 		cp->id = LSM_ID_UNDEF;
6680 	}
6681 }
6682 
selinux_inode_invalidate_secctx(struct inode * inode)6683 static void selinux_inode_invalidate_secctx(struct inode *inode)
6684 {
6685 	struct inode_security_struct *isec = selinux_inode(inode);
6686 
6687 	spin_lock(&isec->lock);
6688 	isec->initialized = LABEL_INVALID;
6689 	spin_unlock(&isec->lock);
6690 }
6691 
6692 /*
6693  *	called with inode->i_mutex locked
6694  */
selinux_inode_notifysecctx(struct inode * inode,void * ctx,u32 ctxlen)6695 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6696 {
6697 	int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6698 					   ctx, ctxlen, 0);
6699 	/* Do not return error when suppressing label (SBLABEL_MNT not set). */
6700 	return rc == -EOPNOTSUPP ? 0 : rc;
6701 }
6702 
6703 /*
6704  *	called with inode->i_mutex locked
6705  */
selinux_inode_setsecctx(struct dentry * dentry,void * ctx,u32 ctxlen)6706 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6707 {
6708 	return __vfs_setxattr_locked(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6709 				     ctx, ctxlen, 0, NULL);
6710 }
6711 
selinux_inode_getsecctx(struct inode * inode,struct lsm_context * cp)6712 static int selinux_inode_getsecctx(struct inode *inode, struct lsm_context *cp)
6713 {
6714 	int len;
6715 	len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6716 					XATTR_SELINUX_SUFFIX,
6717 					(void **)&cp->context, true);
6718 	if (len < 0)
6719 		return len;
6720 	cp->len = len;
6721 	cp->id = LSM_ID_SELINUX;
6722 	return 0;
6723 }
6724 #ifdef CONFIG_KEYS
6725 
selinux_key_alloc(struct key * k,const struct cred * cred,unsigned long flags)6726 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6727 			     unsigned long flags)
6728 {
6729 	const struct task_security_struct *tsec;
6730 	struct key_security_struct *ksec = selinux_key(k);
6731 
6732 	tsec = selinux_cred(cred);
6733 	if (tsec->keycreate_sid)
6734 		ksec->sid = tsec->keycreate_sid;
6735 	else
6736 		ksec->sid = tsec->sid;
6737 
6738 	return 0;
6739 }
6740 
selinux_key_permission(key_ref_t key_ref,const struct cred * cred,enum key_need_perm need_perm)6741 static int selinux_key_permission(key_ref_t key_ref,
6742 				  const struct cred *cred,
6743 				  enum key_need_perm need_perm)
6744 {
6745 	struct key *key;
6746 	struct key_security_struct *ksec;
6747 	u32 perm, sid;
6748 
6749 	switch (need_perm) {
6750 	case KEY_NEED_VIEW:
6751 		perm = KEY__VIEW;
6752 		break;
6753 	case KEY_NEED_READ:
6754 		perm = KEY__READ;
6755 		break;
6756 	case KEY_NEED_WRITE:
6757 		perm = KEY__WRITE;
6758 		break;
6759 	case KEY_NEED_SEARCH:
6760 		perm = KEY__SEARCH;
6761 		break;
6762 	case KEY_NEED_LINK:
6763 		perm = KEY__LINK;
6764 		break;
6765 	case KEY_NEED_SETATTR:
6766 		perm = KEY__SETATTR;
6767 		break;
6768 	case KEY_NEED_UNLINK:
6769 	case KEY_SYSADMIN_OVERRIDE:
6770 	case KEY_AUTHTOKEN_OVERRIDE:
6771 	case KEY_DEFER_PERM_CHECK:
6772 		return 0;
6773 	default:
6774 		WARN_ON(1);
6775 		return -EPERM;
6776 
6777 	}
6778 
6779 	sid = cred_sid(cred);
6780 	key = key_ref_to_ptr(key_ref);
6781 	ksec = selinux_key(key);
6782 
6783 	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6784 }
6785 
selinux_key_getsecurity(struct key * key,char ** _buffer)6786 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6787 {
6788 	struct key_security_struct *ksec = selinux_key(key);
6789 	char *context = NULL;
6790 	unsigned len;
6791 	int rc;
6792 
6793 	rc = security_sid_to_context(ksec->sid,
6794 				     &context, &len);
6795 	if (!rc)
6796 		rc = len;
6797 	*_buffer = context;
6798 	return rc;
6799 }
6800 
6801 #ifdef CONFIG_KEY_NOTIFICATIONS
selinux_watch_key(struct key * key)6802 static int selinux_watch_key(struct key *key)
6803 {
6804 	struct key_security_struct *ksec = selinux_key(key);
6805 	u32 sid = current_sid();
6806 
6807 	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6808 }
6809 #endif
6810 #endif
6811 
6812 #ifdef CONFIG_SECURITY_INFINIBAND
selinux_ib_pkey_access(void * ib_sec,u64 subnet_prefix,u16 pkey_val)6813 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6814 {
6815 	struct common_audit_data ad;
6816 	int err;
6817 	u32 sid = 0;
6818 	struct ib_security_struct *sec = ib_sec;
6819 	struct lsm_ibpkey_audit ibpkey;
6820 
6821 	err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6822 	if (err)
6823 		return err;
6824 
6825 	ad.type = LSM_AUDIT_DATA_IBPKEY;
6826 	ibpkey.subnet_prefix = subnet_prefix;
6827 	ibpkey.pkey = pkey_val;
6828 	ad.u.ibpkey = &ibpkey;
6829 	return avc_has_perm(sec->sid, sid,
6830 			    SECCLASS_INFINIBAND_PKEY,
6831 			    INFINIBAND_PKEY__ACCESS, &ad);
6832 }
6833 
selinux_ib_endport_manage_subnet(void * ib_sec,const char * dev_name,u8 port_num)6834 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6835 					    u8 port_num)
6836 {
6837 	struct common_audit_data ad;
6838 	int err;
6839 	u32 sid = 0;
6840 	struct ib_security_struct *sec = ib_sec;
6841 	struct lsm_ibendport_audit ibendport;
6842 
6843 	err = security_ib_endport_sid(dev_name, port_num,
6844 				      &sid);
6845 
6846 	if (err)
6847 		return err;
6848 
6849 	ad.type = LSM_AUDIT_DATA_IBENDPORT;
6850 	ibendport.dev_name = dev_name;
6851 	ibendport.port = port_num;
6852 	ad.u.ibendport = &ibendport;
6853 	return avc_has_perm(sec->sid, sid,
6854 			    SECCLASS_INFINIBAND_ENDPORT,
6855 			    INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6856 }
6857 
selinux_ib_alloc_security(void * ib_sec)6858 static int selinux_ib_alloc_security(void *ib_sec)
6859 {
6860 	struct ib_security_struct *sec = selinux_ib(ib_sec);
6861 
6862 	sec->sid = current_sid();
6863 	return 0;
6864 }
6865 #endif
6866 
6867 #ifdef CONFIG_BPF_SYSCALL
selinux_bpf(int cmd,union bpf_attr * attr,unsigned int size)6868 static int selinux_bpf(int cmd, union bpf_attr *attr,
6869 				     unsigned int size)
6870 {
6871 	u32 sid = current_sid();
6872 	int ret;
6873 
6874 	switch (cmd) {
6875 	case BPF_MAP_CREATE:
6876 		ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6877 				   NULL);
6878 		break;
6879 	case BPF_PROG_LOAD:
6880 		ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6881 				   NULL);
6882 		break;
6883 	default:
6884 		ret = 0;
6885 		break;
6886 	}
6887 
6888 	return ret;
6889 }
6890 
bpf_map_fmode_to_av(fmode_t fmode)6891 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6892 {
6893 	u32 av = 0;
6894 
6895 	if (fmode & FMODE_READ)
6896 		av |= BPF__MAP_READ;
6897 	if (fmode & FMODE_WRITE)
6898 		av |= BPF__MAP_WRITE;
6899 	return av;
6900 }
6901 
6902 /* This function will check the file pass through unix socket or binder to see
6903  * if it is a bpf related object. And apply corresponding checks on the bpf
6904  * object based on the type. The bpf maps and programs, not like other files and
6905  * socket, are using a shared anonymous inode inside the kernel as their inode.
6906  * So checking that inode cannot identify if the process have privilege to
6907  * access the bpf object and that's why we have to add this additional check in
6908  * selinux_file_receive and selinux_binder_transfer_files.
6909  */
bpf_fd_pass(const struct file * file,u32 sid)6910 static int bpf_fd_pass(const struct file *file, u32 sid)
6911 {
6912 	struct bpf_security_struct *bpfsec;
6913 	struct bpf_prog *prog;
6914 	struct bpf_map *map;
6915 	int ret;
6916 
6917 	if (file->f_op == &bpf_map_fops) {
6918 		map = file->private_data;
6919 		bpfsec = map->security;
6920 		ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6921 				   bpf_map_fmode_to_av(file->f_mode), NULL);
6922 		if (ret)
6923 			return ret;
6924 	} else if (file->f_op == &bpf_prog_fops) {
6925 		prog = file->private_data;
6926 		bpfsec = prog->aux->security;
6927 		ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6928 				   BPF__PROG_RUN, NULL);
6929 		if (ret)
6930 			return ret;
6931 	}
6932 	return 0;
6933 }
6934 
selinux_bpf_map(struct bpf_map * map,fmode_t fmode)6935 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6936 {
6937 	u32 sid = current_sid();
6938 	struct bpf_security_struct *bpfsec;
6939 
6940 	bpfsec = map->security;
6941 	return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6942 			    bpf_map_fmode_to_av(fmode), NULL);
6943 }
6944 
selinux_bpf_prog(struct bpf_prog * prog)6945 static int selinux_bpf_prog(struct bpf_prog *prog)
6946 {
6947 	u32 sid = current_sid();
6948 	struct bpf_security_struct *bpfsec;
6949 
6950 	bpfsec = prog->aux->security;
6951 	return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6952 			    BPF__PROG_RUN, NULL);
6953 }
6954 
selinux_bpf_map_create(struct bpf_map * map,union bpf_attr * attr,struct bpf_token * token)6955 static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
6956 				  struct bpf_token *token)
6957 {
6958 	struct bpf_security_struct *bpfsec;
6959 
6960 	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6961 	if (!bpfsec)
6962 		return -ENOMEM;
6963 
6964 	bpfsec->sid = current_sid();
6965 	map->security = bpfsec;
6966 
6967 	return 0;
6968 }
6969 
selinux_bpf_map_free(struct bpf_map * map)6970 static void selinux_bpf_map_free(struct bpf_map *map)
6971 {
6972 	struct bpf_security_struct *bpfsec = map->security;
6973 
6974 	map->security = NULL;
6975 	kfree(bpfsec);
6976 }
6977 
selinux_bpf_prog_load(struct bpf_prog * prog,union bpf_attr * attr,struct bpf_token * token)6978 static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
6979 				 struct bpf_token *token)
6980 {
6981 	struct bpf_security_struct *bpfsec;
6982 
6983 	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6984 	if (!bpfsec)
6985 		return -ENOMEM;
6986 
6987 	bpfsec->sid = current_sid();
6988 	prog->aux->security = bpfsec;
6989 
6990 	return 0;
6991 }
6992 
selinux_bpf_prog_free(struct bpf_prog * prog)6993 static void selinux_bpf_prog_free(struct bpf_prog *prog)
6994 {
6995 	struct bpf_security_struct *bpfsec = prog->aux->security;
6996 
6997 	prog->aux->security = NULL;
6998 	kfree(bpfsec);
6999 }
7000 
selinux_bpf_token_create(struct bpf_token * token,union bpf_attr * attr,const struct path * path)7001 static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
7002 				    const struct path *path)
7003 {
7004 	struct bpf_security_struct *bpfsec;
7005 
7006 	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
7007 	if (!bpfsec)
7008 		return -ENOMEM;
7009 
7010 	bpfsec->sid = current_sid();
7011 	token->security = bpfsec;
7012 
7013 	return 0;
7014 }
7015 
selinux_bpf_token_free(struct bpf_token * token)7016 static void selinux_bpf_token_free(struct bpf_token *token)
7017 {
7018 	struct bpf_security_struct *bpfsec = token->security;
7019 
7020 	token->security = NULL;
7021 	kfree(bpfsec);
7022 }
7023 #endif
7024 
7025 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
7026 	.lbs_cred = sizeof(struct task_security_struct),
7027 	.lbs_file = sizeof(struct file_security_struct),
7028 	.lbs_inode = sizeof(struct inode_security_struct),
7029 	.lbs_ipc = sizeof(struct ipc_security_struct),
7030 	.lbs_key = sizeof(struct key_security_struct),
7031 	.lbs_msg_msg = sizeof(struct msg_security_struct),
7032 #ifdef CONFIG_PERF_EVENTS
7033 	.lbs_perf_event = sizeof(struct perf_event_security_struct),
7034 #endif
7035 	.lbs_sock = sizeof(struct sk_security_struct),
7036 	.lbs_superblock = sizeof(struct superblock_security_struct),
7037 	.lbs_xattr_count = SELINUX_INODE_INIT_XATTRS,
7038 	.lbs_tun_dev = sizeof(struct tun_security_struct),
7039 	.lbs_ib = sizeof(struct ib_security_struct),
7040 };
7041 
7042 #ifdef CONFIG_PERF_EVENTS
selinux_perf_event_open(struct perf_event_attr * attr,int type)7043 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
7044 {
7045 	u32 requested, sid = current_sid();
7046 
7047 	if (type == PERF_SECURITY_OPEN)
7048 		requested = PERF_EVENT__OPEN;
7049 	else if (type == PERF_SECURITY_CPU)
7050 		requested = PERF_EVENT__CPU;
7051 	else if (type == PERF_SECURITY_KERNEL)
7052 		requested = PERF_EVENT__KERNEL;
7053 	else if (type == PERF_SECURITY_TRACEPOINT)
7054 		requested = PERF_EVENT__TRACEPOINT;
7055 	else
7056 		return -EINVAL;
7057 
7058 	return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
7059 			    requested, NULL);
7060 }
7061 
selinux_perf_event_alloc(struct perf_event * event)7062 static int selinux_perf_event_alloc(struct perf_event *event)
7063 {
7064 	struct perf_event_security_struct *perfsec;
7065 
7066 	perfsec = selinux_perf_event(event->security);
7067 	perfsec->sid = current_sid();
7068 
7069 	return 0;
7070 }
7071 
selinux_perf_event_read(struct perf_event * event)7072 static int selinux_perf_event_read(struct perf_event *event)
7073 {
7074 	struct perf_event_security_struct *perfsec = event->security;
7075 	u32 sid = current_sid();
7076 
7077 	return avc_has_perm(sid, perfsec->sid,
7078 			    SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7079 }
7080 
selinux_perf_event_write(struct perf_event * event)7081 static int selinux_perf_event_write(struct perf_event *event)
7082 {
7083 	struct perf_event_security_struct *perfsec = event->security;
7084 	u32 sid = current_sid();
7085 
7086 	return avc_has_perm(sid, perfsec->sid,
7087 			    SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7088 }
7089 #endif
7090 
7091 #ifdef CONFIG_IO_URING
7092 /**
7093  * selinux_uring_override_creds - check the requested cred override
7094  * @new: the target creds
7095  *
7096  * Check to see if the current task is allowed to override it's credentials
7097  * to service an io_uring operation.
7098  */
selinux_uring_override_creds(const struct cred * new)7099 static int selinux_uring_override_creds(const struct cred *new)
7100 {
7101 	return avc_has_perm(current_sid(), cred_sid(new),
7102 			    SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
7103 }
7104 
7105 /**
7106  * selinux_uring_sqpoll - check if a io_uring polling thread can be created
7107  *
7108  * Check to see if the current task is allowed to create a new io_uring
7109  * kernel polling thread.
7110  */
selinux_uring_sqpoll(void)7111 static int selinux_uring_sqpoll(void)
7112 {
7113 	u32 sid = current_sid();
7114 
7115 	return avc_has_perm(sid, sid,
7116 			    SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
7117 }
7118 
7119 /**
7120  * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
7121  * @ioucmd: the io_uring command structure
7122  *
7123  * Check to see if the current domain is allowed to execute an
7124  * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
7125  *
7126  */
selinux_uring_cmd(struct io_uring_cmd * ioucmd)7127 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
7128 {
7129 	struct file *file = ioucmd->file;
7130 	struct inode *inode = file_inode(file);
7131 	struct inode_security_struct *isec = selinux_inode(inode);
7132 	struct common_audit_data ad;
7133 
7134 	ad.type = LSM_AUDIT_DATA_FILE;
7135 	ad.u.file = file;
7136 
7137 	return avc_has_perm(current_sid(), isec->sid,
7138 			    SECCLASS_IO_URING, IO_URING__CMD, &ad);
7139 }
7140 #endif /* CONFIG_IO_URING */
7141 
7142 static const struct lsm_id selinux_lsmid = {
7143 	.name = "selinux",
7144 	.id = LSM_ID_SELINUX,
7145 };
7146 
7147 /*
7148  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7149  * 1. any hooks that don't belong to (2.) or (3.) below,
7150  * 2. hooks that both access structures allocated by other hooks, and allocate
7151  *    structures that can be later accessed by other hooks (mostly "cloning"
7152  *    hooks),
7153  * 3. hooks that only allocate structures that can be later accessed by other
7154  *    hooks ("allocating" hooks).
7155  *
7156  * Please follow block comment delimiters in the list to keep this order.
7157  */
7158 static struct security_hook_list selinux_hooks[] __ro_after_init = {
7159 	LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7160 	LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7161 	LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7162 	LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7163 
7164 	LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7165 	LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7166 	LSM_HOOK_INIT(capget, selinux_capget),
7167 	LSM_HOOK_INIT(capset, selinux_capset),
7168 	LSM_HOOK_INIT(capable, selinux_capable),
7169 	LSM_HOOK_INIT(quotactl, selinux_quotactl),
7170 	LSM_HOOK_INIT(quota_on, selinux_quota_on),
7171 	LSM_HOOK_INIT(syslog, selinux_syslog),
7172 	LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7173 
7174 	LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7175 
7176 	LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7177 	LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7178 	LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7179 
7180 	LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7181 	LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7182 	LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7183 	LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7184 	LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7185 	LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7186 	LSM_HOOK_INIT(sb_mount, selinux_mount),
7187 	LSM_HOOK_INIT(sb_umount, selinux_umount),
7188 	LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7189 	LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7190 
7191 	LSM_HOOK_INIT(move_mount, selinux_move_mount),
7192 
7193 	LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7194 	LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7195 
7196 	LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7197 	LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7198 	LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7199 	LSM_HOOK_INIT(inode_create, selinux_inode_create),
7200 	LSM_HOOK_INIT(inode_link, selinux_inode_link),
7201 	LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7202 	LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7203 	LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7204 	LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7205 	LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7206 	LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7207 	LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7208 	LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7209 	LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7210 	LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7211 	LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7212 	LSM_HOOK_INIT(inode_xattr_skipcap, selinux_inode_xattr_skipcap),
7213 	LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7214 	LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7215 	LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7216 	LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7217 	LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7218 	LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7219 	LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7220 	LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7221 	LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7222 	LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7223 	LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7224 	LSM_HOOK_INIT(inode_getlsmprop, selinux_inode_getlsmprop),
7225 	LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7226 	LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7227 	LSM_HOOK_INIT(path_notify, selinux_path_notify),
7228 
7229 	LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7230 
7231 	LSM_HOOK_INIT(file_permission, selinux_file_permission),
7232 	LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7233 	LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7234 	LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat),
7235 	LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7236 	LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7237 	LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7238 	LSM_HOOK_INIT(file_lock, selinux_file_lock),
7239 	LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7240 	LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7241 	LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7242 	LSM_HOOK_INIT(file_receive, selinux_file_receive),
7243 
7244 	LSM_HOOK_INIT(file_open, selinux_file_open),
7245 
7246 	LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7247 	LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7248 	LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7249 	LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7250 	LSM_HOOK_INIT(cred_getlsmprop, selinux_cred_getlsmprop),
7251 	LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7252 	LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7253 	LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7254 	LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7255 	LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7256 	LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7257 	LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7258 	LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7259 	LSM_HOOK_INIT(current_getlsmprop_subj, selinux_current_getlsmprop_subj),
7260 	LSM_HOOK_INIT(task_getlsmprop_obj, selinux_task_getlsmprop_obj),
7261 	LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7262 	LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7263 	LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7264 	LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7265 	LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7266 	LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7267 	LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7268 	LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7269 	LSM_HOOK_INIT(task_kill, selinux_task_kill),
7270 	LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7271 	LSM_HOOK_INIT(userns_create, selinux_userns_create),
7272 
7273 	LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7274 	LSM_HOOK_INIT(ipc_getlsmprop, selinux_ipc_getlsmprop),
7275 
7276 	LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7277 	LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7278 	LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7279 	LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7280 
7281 	LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7282 	LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7283 	LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7284 
7285 	LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7286 	LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7287 	LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7288 
7289 	LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7290 
7291 	LSM_HOOK_INIT(getselfattr, selinux_getselfattr),
7292 	LSM_HOOK_INIT(setselfattr, selinux_setselfattr),
7293 	LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7294 	LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7295 
7296 	LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7297 	LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7298 	LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7299 	LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7300 	LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7301 	LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7302 
7303 	LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7304 	LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7305 
7306 	LSM_HOOK_INIT(socket_create, selinux_socket_create),
7307 	LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7308 	LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7309 	LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7310 	LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7311 	LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7312 	LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7313 	LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7314 	LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7315 	LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7316 	LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7317 	LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7318 	LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7319 	LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7320 	LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7321 	LSM_HOOK_INIT(socket_getpeersec_stream,
7322 			selinux_socket_getpeersec_stream),
7323 	LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7324 	LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7325 	LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7326 	LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7327 	LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7328 	LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7329 	LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7330 	LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7331 	LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7332 	LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow),
7333 	LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7334 	LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7335 	LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7336 	LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7337 	LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7338 	LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7339 	LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7340 	LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7341 	LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7342 	LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7343 	LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7344 #ifdef CONFIG_SECURITY_INFINIBAND
7345 	LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7346 	LSM_HOOK_INIT(ib_endport_manage_subnet,
7347 		      selinux_ib_endport_manage_subnet),
7348 #endif
7349 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7350 	LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7351 	LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7352 	LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7353 	LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7354 	LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7355 	LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7356 			selinux_xfrm_state_pol_flow_match),
7357 	LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7358 #endif
7359 
7360 #ifdef CONFIG_KEYS
7361 	LSM_HOOK_INIT(key_permission, selinux_key_permission),
7362 	LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7363 #ifdef CONFIG_KEY_NOTIFICATIONS
7364 	LSM_HOOK_INIT(watch_key, selinux_watch_key),
7365 #endif
7366 #endif
7367 
7368 #ifdef CONFIG_AUDIT
7369 	LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7370 	LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7371 	LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7372 #endif
7373 
7374 #ifdef CONFIG_BPF_SYSCALL
7375 	LSM_HOOK_INIT(bpf, selinux_bpf),
7376 	LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7377 	LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7378 	LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free),
7379 	LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free),
7380 	LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free),
7381 #endif
7382 
7383 #ifdef CONFIG_PERF_EVENTS
7384 	LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7385 	LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7386 	LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7387 #endif
7388 
7389 #ifdef CONFIG_IO_URING
7390 	LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7391 	LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7392 	LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7393 #endif
7394 
7395 	/*
7396 	 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7397 	 */
7398 	LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount),
7399 	LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7400 	LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7401 	LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7402 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7403 	LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7404 #endif
7405 
7406 	/*
7407 	 * PUT "ALLOCATING" HOOKS HERE
7408 	 */
7409 	LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7410 	LSM_HOOK_INIT(msg_queue_alloc_security,
7411 		      selinux_msg_queue_alloc_security),
7412 	LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7413 	LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7414 	LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7415 	LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7416 	LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7417 	LSM_HOOK_INIT(lsmprop_to_secctx, selinux_lsmprop_to_secctx),
7418 	LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7419 	LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7420 	LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7421 #ifdef CONFIG_SECURITY_INFINIBAND
7422 	LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7423 #endif
7424 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7425 	LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7426 	LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7427 	LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7428 		      selinux_xfrm_state_alloc_acquire),
7429 #endif
7430 #ifdef CONFIG_KEYS
7431 	LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7432 #endif
7433 #ifdef CONFIG_AUDIT
7434 	LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7435 #endif
7436 #ifdef CONFIG_BPF_SYSCALL
7437 	LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create),
7438 	LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load),
7439 	LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create),
7440 #endif
7441 #ifdef CONFIG_PERF_EVENTS
7442 	LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7443 #endif
7444 };
7445 
selinux_init(void)7446 static __init int selinux_init(void)
7447 {
7448 	pr_info("SELinux:  Initializing.\n");
7449 
7450 	memset(&selinux_state, 0, sizeof(selinux_state));
7451 	enforcing_set(selinux_enforcing_boot);
7452 	selinux_avc_init();
7453 	mutex_init(&selinux_state.status_lock);
7454 	mutex_init(&selinux_state.policy_mutex);
7455 
7456 	/* Set the security state for the initial task. */
7457 	cred_init_security();
7458 
7459 	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7460 	if (!default_noexec)
7461 		pr_notice("SELinux:  virtual memory is executable by default\n");
7462 
7463 	avc_init();
7464 
7465 	avtab_cache_init();
7466 
7467 	ebitmap_cache_init();
7468 
7469 	hashtab_cache_init();
7470 
7471 	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
7472 			   &selinux_lsmid);
7473 
7474 	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7475 		panic("SELinux: Unable to register AVC netcache callback\n");
7476 
7477 	if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7478 		panic("SELinux: Unable to register AVC LSM notifier callback\n");
7479 
7480 	if (selinux_enforcing_boot)
7481 		pr_debug("SELinux:  Starting in enforcing mode\n");
7482 	else
7483 		pr_debug("SELinux:  Starting in permissive mode\n");
7484 
7485 	fs_validate_description("selinux", selinux_fs_parameters);
7486 
7487 	return 0;
7488 }
7489 
delayed_superblock_init(struct super_block * sb,void * unused)7490 static void delayed_superblock_init(struct super_block *sb, void *unused)
7491 {
7492 	selinux_set_mnt_opts(sb, NULL, 0, NULL);
7493 }
7494 
selinux_complete_init(void)7495 void selinux_complete_init(void)
7496 {
7497 	pr_debug("SELinux:  Completing initialization.\n");
7498 
7499 	/* Set up any superblocks initialized prior to the policy load. */
7500 	pr_debug("SELinux:  Setting up existing superblocks.\n");
7501 	iterate_supers(delayed_superblock_init, NULL);
7502 }
7503 
7504 /* SELinux requires early initialization in order to label
7505    all processes and objects when they are created. */
7506 DEFINE_LSM(selinux) = {
7507 	.name = "selinux",
7508 	.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7509 	.enabled = &selinux_enabled_boot,
7510 	.blobs = &selinux_blob_sizes,
7511 	.init = selinux_init,
7512 };
7513 
7514 #if defined(CONFIG_NETFILTER)
7515 static const struct nf_hook_ops selinux_nf_ops[] = {
7516 	{
7517 		.hook =		selinux_ip_postroute,
7518 		.pf =		NFPROTO_IPV4,
7519 		.hooknum =	NF_INET_POST_ROUTING,
7520 		.priority =	NF_IP_PRI_SELINUX_LAST,
7521 	},
7522 	{
7523 		.hook =		selinux_ip_forward,
7524 		.pf =		NFPROTO_IPV4,
7525 		.hooknum =	NF_INET_FORWARD,
7526 		.priority =	NF_IP_PRI_SELINUX_FIRST,
7527 	},
7528 	{
7529 		.hook =		selinux_ip_output,
7530 		.pf =		NFPROTO_IPV4,
7531 		.hooknum =	NF_INET_LOCAL_OUT,
7532 		.priority =	NF_IP_PRI_SELINUX_FIRST,
7533 	},
7534 #if IS_ENABLED(CONFIG_IPV6)
7535 	{
7536 		.hook =		selinux_ip_postroute,
7537 		.pf =		NFPROTO_IPV6,
7538 		.hooknum =	NF_INET_POST_ROUTING,
7539 		.priority =	NF_IP6_PRI_SELINUX_LAST,
7540 	},
7541 	{
7542 		.hook =		selinux_ip_forward,
7543 		.pf =		NFPROTO_IPV6,
7544 		.hooknum =	NF_INET_FORWARD,
7545 		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7546 	},
7547 	{
7548 		.hook =		selinux_ip_output,
7549 		.pf =		NFPROTO_IPV6,
7550 		.hooknum =	NF_INET_LOCAL_OUT,
7551 		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7552 	},
7553 #endif	/* IPV6 */
7554 };
7555 
selinux_nf_register(struct net * net)7556 static int __net_init selinux_nf_register(struct net *net)
7557 {
7558 	return nf_register_net_hooks(net, selinux_nf_ops,
7559 				     ARRAY_SIZE(selinux_nf_ops));
7560 }
7561 
selinux_nf_unregister(struct net * net)7562 static void __net_exit selinux_nf_unregister(struct net *net)
7563 {
7564 	nf_unregister_net_hooks(net, selinux_nf_ops,
7565 				ARRAY_SIZE(selinux_nf_ops));
7566 }
7567 
7568 static struct pernet_operations selinux_net_ops = {
7569 	.init = selinux_nf_register,
7570 	.exit = selinux_nf_unregister,
7571 };
7572 
selinux_nf_ip_init(void)7573 static int __init selinux_nf_ip_init(void)
7574 {
7575 	int err;
7576 
7577 	if (!selinux_enabled_boot)
7578 		return 0;
7579 
7580 	pr_debug("SELinux:  Registering netfilter hooks\n");
7581 
7582 	err = register_pernet_subsys(&selinux_net_ops);
7583 	if (err)
7584 		panic("SELinux: register_pernet_subsys: error %d\n", err);
7585 
7586 	return 0;
7587 }
7588 __initcall(selinux_nf_ip_init);
7589 #endif /* CONFIG_NETFILTER */
7590