xref: /linux/security/selinux/hooks.c (revision 5b0eea835d4e9cb5229e696c5763929fc2394f39)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  NSA Security-Enhanced Linux (SELinux) security module
4  *
5  *  This file contains the SELinux hook function implementations.
6  *
7  *  Authors:  Stephen Smalley, <sds@tycho.nsa.gov>
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 <linux/bpf.h>
89 #include <linux/kernfs.h>
90 #include <linux/stringhash.h>	/* for hashlen_string() */
91 #include <uapi/linux/mount.h>
92 #include <linux/fsnotify.h>
93 #include <linux/fanotify.h>
94 #include <linux/io_uring.h>
95 
96 #include "avc.h"
97 #include "objsec.h"
98 #include "netif.h"
99 #include "netnode.h"
100 #include "netport.h"
101 #include "ibpkey.h"
102 #include "xfrm.h"
103 #include "netlabel.h"
104 #include "audit.h"
105 #include "avc_ss.h"
106 
107 struct selinux_state selinux_state;
108 
109 /* SECMARK reference count */
110 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
111 
112 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
113 static int selinux_enforcing_boot __initdata;
114 
115 static int __init enforcing_setup(char *str)
116 {
117 	unsigned long enforcing;
118 	if (!kstrtoul(str, 0, &enforcing))
119 		selinux_enforcing_boot = enforcing ? 1 : 0;
120 	return 1;
121 }
122 __setup("enforcing=", enforcing_setup);
123 #else
124 #define selinux_enforcing_boot 1
125 #endif
126 
127 int selinux_enabled_boot __initdata = 1;
128 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
129 static int __init selinux_enabled_setup(char *str)
130 {
131 	unsigned long enabled;
132 	if (!kstrtoul(str, 0, &enabled))
133 		selinux_enabled_boot = enabled ? 1 : 0;
134 	return 1;
135 }
136 __setup("selinux=", selinux_enabled_setup);
137 #endif
138 
139 static int __init checkreqprot_setup(char *str)
140 {
141 	unsigned long checkreqprot;
142 
143 	if (!kstrtoul(str, 0, &checkreqprot)) {
144 		if (checkreqprot)
145 			pr_err("SELinux: checkreqprot set to 1 via kernel parameter.  This is no longer supported.\n");
146 	}
147 	return 1;
148 }
149 __setup("checkreqprot=", checkreqprot_setup);
150 
151 /**
152  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
153  *
154  * Description:
155  * This function checks the SECMARK reference counter to see if any SECMARK
156  * targets are currently configured, if the reference counter is greater than
157  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
158  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
159  * policy capability is enabled, SECMARK is always considered enabled.
160  *
161  */
162 static int selinux_secmark_enabled(void)
163 {
164 	return (selinux_policycap_alwaysnetwork() ||
165 		atomic_read(&selinux_secmark_refcount));
166 }
167 
168 /**
169  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
170  *
171  * Description:
172  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
173  * (1) if any are enabled or false (0) if neither are enabled.  If the
174  * always_check_network policy capability is enabled, peer labeling
175  * is always considered enabled.
176  *
177  */
178 static int selinux_peerlbl_enabled(void)
179 {
180 	return (selinux_policycap_alwaysnetwork() ||
181 		netlbl_enabled() || selinux_xfrm_enabled());
182 }
183 
184 static int selinux_netcache_avc_callback(u32 event)
185 {
186 	if (event == AVC_CALLBACK_RESET) {
187 		sel_netif_flush();
188 		sel_netnode_flush();
189 		sel_netport_flush();
190 		synchronize_net();
191 	}
192 	return 0;
193 }
194 
195 static int selinux_lsm_notifier_avc_callback(u32 event)
196 {
197 	if (event == AVC_CALLBACK_RESET) {
198 		sel_ib_pkey_flush();
199 		call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
200 	}
201 
202 	return 0;
203 }
204 
205 /*
206  * initialise the security for the init task
207  */
208 static void cred_init_security(void)
209 {
210 	struct task_security_struct *tsec;
211 
212 	tsec = selinux_cred(unrcu_pointer(current->real_cred));
213 	tsec->osid = tsec->sid = SECINITSID_KERNEL;
214 }
215 
216 /*
217  * get the security ID of a set of credentials
218  */
219 static inline u32 cred_sid(const struct cred *cred)
220 {
221 	const struct task_security_struct *tsec;
222 
223 	tsec = selinux_cred(cred);
224 	return tsec->sid;
225 }
226 
227 /*
228  * get the objective security ID of a task
229  */
230 static inline u32 task_sid_obj(const struct task_struct *task)
231 {
232 	u32 sid;
233 
234 	rcu_read_lock();
235 	sid = cred_sid(__task_cred(task));
236 	rcu_read_unlock();
237 	return sid;
238 }
239 
240 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
241 
242 /*
243  * Try reloading inode security labels that have been marked as invalid.  The
244  * @may_sleep parameter indicates when sleeping and thus reloading labels is
245  * allowed; when set to false, returns -ECHILD when the label is
246  * invalid.  The @dentry parameter should be set to a dentry of the inode.
247  */
248 static int __inode_security_revalidate(struct inode *inode,
249 				       struct dentry *dentry,
250 				       bool may_sleep)
251 {
252 	struct inode_security_struct *isec = selinux_inode(inode);
253 
254 	might_sleep_if(may_sleep);
255 
256 	if (selinux_initialized() &&
257 	    isec->initialized != LABEL_INITIALIZED) {
258 		if (!may_sleep)
259 			return -ECHILD;
260 
261 		/*
262 		 * Try reloading the inode security label.  This will fail if
263 		 * @opt_dentry is NULL and no dentry for this inode can be
264 		 * found; in that case, continue using the old label.
265 		 */
266 		inode_doinit_with_dentry(inode, dentry);
267 	}
268 	return 0;
269 }
270 
271 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
272 {
273 	return selinux_inode(inode);
274 }
275 
276 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
277 {
278 	int error;
279 
280 	error = __inode_security_revalidate(inode, NULL, !rcu);
281 	if (error)
282 		return ERR_PTR(error);
283 	return selinux_inode(inode);
284 }
285 
286 /*
287  * Get the security label of an inode.
288  */
289 static struct inode_security_struct *inode_security(struct inode *inode)
290 {
291 	__inode_security_revalidate(inode, NULL, true);
292 	return selinux_inode(inode);
293 }
294 
295 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
296 {
297 	struct inode *inode = d_backing_inode(dentry);
298 
299 	return selinux_inode(inode);
300 }
301 
302 /*
303  * Get the security label of a dentry's backing inode.
304  */
305 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
306 {
307 	struct inode *inode = d_backing_inode(dentry);
308 
309 	__inode_security_revalidate(inode, dentry, true);
310 	return selinux_inode(inode);
311 }
312 
313 static void inode_free_security(struct inode *inode)
314 {
315 	struct inode_security_struct *isec = selinux_inode(inode);
316 	struct superblock_security_struct *sbsec;
317 
318 	if (!isec)
319 		return;
320 	sbsec = selinux_superblock(inode->i_sb);
321 	/*
322 	 * As not all inode security structures are in a list, we check for
323 	 * empty list outside of the lock to make sure that we won't waste
324 	 * time taking a lock doing nothing.
325 	 *
326 	 * The list_del_init() function can be safely called more than once.
327 	 * It should not be possible for this function to be called with
328 	 * concurrent list_add(), but for better safety against future changes
329 	 * in the code, we use list_empty_careful() here.
330 	 */
331 	if (!list_empty_careful(&isec->list)) {
332 		spin_lock(&sbsec->isec_lock);
333 		list_del_init(&isec->list);
334 		spin_unlock(&sbsec->isec_lock);
335 	}
336 }
337 
338 struct selinux_mnt_opts {
339 	u32 fscontext_sid;
340 	u32 context_sid;
341 	u32 rootcontext_sid;
342 	u32 defcontext_sid;
343 };
344 
345 static void selinux_free_mnt_opts(void *mnt_opts)
346 {
347 	kfree(mnt_opts);
348 }
349 
350 enum {
351 	Opt_error = -1,
352 	Opt_context = 0,
353 	Opt_defcontext = 1,
354 	Opt_fscontext = 2,
355 	Opt_rootcontext = 3,
356 	Opt_seclabel = 4,
357 };
358 
359 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
360 static const struct {
361 	const char *name;
362 	int len;
363 	int opt;
364 	bool has_arg;
365 } tokens[] = {
366 	A(context, true),
367 	A(fscontext, true),
368 	A(defcontext, true),
369 	A(rootcontext, true),
370 	A(seclabel, false),
371 };
372 #undef A
373 
374 static int match_opt_prefix(char *s, int l, char **arg)
375 {
376 	int i;
377 
378 	for (i = 0; i < ARRAY_SIZE(tokens); i++) {
379 		size_t len = tokens[i].len;
380 		if (len > l || memcmp(s, tokens[i].name, len))
381 			continue;
382 		if (tokens[i].has_arg) {
383 			if (len == l || s[len] != '=')
384 				continue;
385 			*arg = s + len + 1;
386 		} else if (len != l)
387 			continue;
388 		return tokens[i].opt;
389 	}
390 	return Opt_error;
391 }
392 
393 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
394 
395 static int may_context_mount_sb_relabel(u32 sid,
396 			struct superblock_security_struct *sbsec,
397 			const struct cred *cred)
398 {
399 	const struct task_security_struct *tsec = selinux_cred(cred);
400 	int rc;
401 
402 	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
403 			  FILESYSTEM__RELABELFROM, NULL);
404 	if (rc)
405 		return rc;
406 
407 	rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
408 			  FILESYSTEM__RELABELTO, NULL);
409 	return rc;
410 }
411 
412 static int may_context_mount_inode_relabel(u32 sid,
413 			struct superblock_security_struct *sbsec,
414 			const struct cred *cred)
415 {
416 	const struct task_security_struct *tsec = selinux_cred(cred);
417 	int rc;
418 	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
419 			  FILESYSTEM__RELABELFROM, NULL);
420 	if (rc)
421 		return rc;
422 
423 	rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
424 			  FILESYSTEM__ASSOCIATE, NULL);
425 	return rc;
426 }
427 
428 static int selinux_is_genfs_special_handling(struct super_block *sb)
429 {
430 	/* Special handling. Genfs but also in-core setxattr handler */
431 	return	!strcmp(sb->s_type->name, "sysfs") ||
432 		!strcmp(sb->s_type->name, "pstore") ||
433 		!strcmp(sb->s_type->name, "debugfs") ||
434 		!strcmp(sb->s_type->name, "tracefs") ||
435 		!strcmp(sb->s_type->name, "rootfs") ||
436 		(selinux_policycap_cgroupseclabel() &&
437 		 (!strcmp(sb->s_type->name, "cgroup") ||
438 		  !strcmp(sb->s_type->name, "cgroup2")));
439 }
440 
441 static int selinux_is_sblabel_mnt(struct super_block *sb)
442 {
443 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
444 
445 	/*
446 	 * IMPORTANT: Double-check logic in this function when adding a new
447 	 * SECURITY_FS_USE_* definition!
448 	 */
449 	BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
450 
451 	switch (sbsec->behavior) {
452 	case SECURITY_FS_USE_XATTR:
453 	case SECURITY_FS_USE_TRANS:
454 	case SECURITY_FS_USE_TASK:
455 	case SECURITY_FS_USE_NATIVE:
456 		return 1;
457 
458 	case SECURITY_FS_USE_GENFS:
459 		return selinux_is_genfs_special_handling(sb);
460 
461 	/* Never allow relabeling on context mounts */
462 	case SECURITY_FS_USE_MNTPOINT:
463 	case SECURITY_FS_USE_NONE:
464 	default:
465 		return 0;
466 	}
467 }
468 
469 static int sb_check_xattr_support(struct super_block *sb)
470 {
471 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
472 	struct dentry *root = sb->s_root;
473 	struct inode *root_inode = d_backing_inode(root);
474 	u32 sid;
475 	int rc;
476 
477 	/*
478 	 * Make sure that the xattr handler exists and that no
479 	 * error other than -ENODATA is returned by getxattr on
480 	 * the root directory.  -ENODATA is ok, as this may be
481 	 * the first boot of the SELinux kernel before we have
482 	 * assigned xattr values to the filesystem.
483 	 */
484 	if (!(root_inode->i_opflags & IOP_XATTR)) {
485 		pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
486 			sb->s_id, sb->s_type->name);
487 		goto fallback;
488 	}
489 
490 	rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
491 	if (rc < 0 && rc != -ENODATA) {
492 		if (rc == -EOPNOTSUPP) {
493 			pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
494 				sb->s_id, sb->s_type->name);
495 			goto fallback;
496 		} else {
497 			pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
498 				sb->s_id, sb->s_type->name, -rc);
499 			return rc;
500 		}
501 	}
502 	return 0;
503 
504 fallback:
505 	/* No xattr support - try to fallback to genfs if possible. */
506 	rc = security_genfs_sid(sb->s_type->name, "/",
507 				SECCLASS_DIR, &sid);
508 	if (rc)
509 		return -EOPNOTSUPP;
510 
511 	pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
512 		sb->s_id, sb->s_type->name);
513 	sbsec->behavior = SECURITY_FS_USE_GENFS;
514 	sbsec->sid = sid;
515 	return 0;
516 }
517 
518 static int sb_finish_set_opts(struct super_block *sb)
519 {
520 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
521 	struct dentry *root = sb->s_root;
522 	struct inode *root_inode = d_backing_inode(root);
523 	int rc = 0;
524 
525 	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
526 		rc = sb_check_xattr_support(sb);
527 		if (rc)
528 			return rc;
529 	}
530 
531 	sbsec->flags |= SE_SBINITIALIZED;
532 
533 	/*
534 	 * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
535 	 * leave the flag untouched because sb_clone_mnt_opts might be handing
536 	 * us a superblock that needs the flag to be cleared.
537 	 */
538 	if (selinux_is_sblabel_mnt(sb))
539 		sbsec->flags |= SBLABEL_MNT;
540 	else
541 		sbsec->flags &= ~SBLABEL_MNT;
542 
543 	/* Initialize the root inode. */
544 	rc = inode_doinit_with_dentry(root_inode, root);
545 
546 	/* Initialize any other inodes associated with the superblock, e.g.
547 	   inodes created prior to initial policy load or inodes created
548 	   during get_sb by a pseudo filesystem that directly
549 	   populates itself. */
550 	spin_lock(&sbsec->isec_lock);
551 	while (!list_empty(&sbsec->isec_head)) {
552 		struct inode_security_struct *isec =
553 				list_first_entry(&sbsec->isec_head,
554 					   struct inode_security_struct, list);
555 		struct inode *inode = isec->inode;
556 		list_del_init(&isec->list);
557 		spin_unlock(&sbsec->isec_lock);
558 		inode = igrab(inode);
559 		if (inode) {
560 			if (!IS_PRIVATE(inode))
561 				inode_doinit_with_dentry(inode, NULL);
562 			iput(inode);
563 		}
564 		spin_lock(&sbsec->isec_lock);
565 	}
566 	spin_unlock(&sbsec->isec_lock);
567 	return rc;
568 }
569 
570 static int bad_option(struct superblock_security_struct *sbsec, char flag,
571 		      u32 old_sid, u32 new_sid)
572 {
573 	char mnt_flags = sbsec->flags & SE_MNTMASK;
574 
575 	/* check if the old mount command had the same options */
576 	if (sbsec->flags & SE_SBINITIALIZED)
577 		if (!(sbsec->flags & flag) ||
578 		    (old_sid != new_sid))
579 			return 1;
580 
581 	/* check if we were passed the same options twice,
582 	 * aka someone passed context=a,context=b
583 	 */
584 	if (!(sbsec->flags & SE_SBINITIALIZED))
585 		if (mnt_flags & flag)
586 			return 1;
587 	return 0;
588 }
589 
590 /*
591  * Allow filesystems with binary mount data to explicitly set mount point
592  * labeling information.
593  */
594 static int selinux_set_mnt_opts(struct super_block *sb,
595 				void *mnt_opts,
596 				unsigned long kern_flags,
597 				unsigned long *set_kern_flags)
598 {
599 	const struct cred *cred = current_cred();
600 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
601 	struct dentry *root = sb->s_root;
602 	struct selinux_mnt_opts *opts = mnt_opts;
603 	struct inode_security_struct *root_isec;
604 	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
605 	u32 defcontext_sid = 0;
606 	int rc = 0;
607 
608 	/*
609 	 * Specifying internal flags without providing a place to
610 	 * place the results is not allowed
611 	 */
612 	if (kern_flags && !set_kern_flags)
613 		return -EINVAL;
614 
615 	mutex_lock(&sbsec->lock);
616 
617 	if (!selinux_initialized()) {
618 		if (!opts) {
619 			/* Defer initialization until selinux_complete_init,
620 			   after the initial policy is loaded and the security
621 			   server is ready to handle calls. */
622 			if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
623 				sbsec->flags |= SE_SBNATIVE;
624 				*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
625 			}
626 			goto out;
627 		}
628 		rc = -EINVAL;
629 		pr_warn("SELinux: Unable to set superblock options "
630 			"before the security server is initialized\n");
631 		goto out;
632 	}
633 
634 	/*
635 	 * Binary mount data FS will come through this function twice.  Once
636 	 * from an explicit call and once from the generic calls from the vfs.
637 	 * Since the generic VFS calls will not contain any security mount data
638 	 * we need to skip the double mount verification.
639 	 *
640 	 * This does open a hole in which we will not notice if the first
641 	 * mount using this sb set explicit options and a second mount using
642 	 * this sb does not set any security options.  (The first options
643 	 * will be used for both mounts)
644 	 */
645 	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
646 	    && !opts)
647 		goto out;
648 
649 	root_isec = backing_inode_security_novalidate(root);
650 
651 	/*
652 	 * parse the mount options, check if they are valid sids.
653 	 * also check if someone is trying to mount the same sb more
654 	 * than once with different security options.
655 	 */
656 	if (opts) {
657 		if (opts->fscontext_sid) {
658 			fscontext_sid = opts->fscontext_sid;
659 			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
660 					fscontext_sid))
661 				goto out_double_mount;
662 			sbsec->flags |= FSCONTEXT_MNT;
663 		}
664 		if (opts->context_sid) {
665 			context_sid = opts->context_sid;
666 			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
667 					context_sid))
668 				goto out_double_mount;
669 			sbsec->flags |= CONTEXT_MNT;
670 		}
671 		if (opts->rootcontext_sid) {
672 			rootcontext_sid = opts->rootcontext_sid;
673 			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
674 					rootcontext_sid))
675 				goto out_double_mount;
676 			sbsec->flags |= ROOTCONTEXT_MNT;
677 		}
678 		if (opts->defcontext_sid) {
679 			defcontext_sid = opts->defcontext_sid;
680 			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
681 					defcontext_sid))
682 				goto out_double_mount;
683 			sbsec->flags |= DEFCONTEXT_MNT;
684 		}
685 	}
686 
687 	if (sbsec->flags & SE_SBINITIALIZED) {
688 		/* previously mounted with options, but not on this attempt? */
689 		if ((sbsec->flags & SE_MNTMASK) && !opts)
690 			goto out_double_mount;
691 		rc = 0;
692 		goto out;
693 	}
694 
695 	if (strcmp(sb->s_type->name, "proc") == 0)
696 		sbsec->flags |= SE_SBPROC | SE_SBGENFS;
697 
698 	if (!strcmp(sb->s_type->name, "debugfs") ||
699 	    !strcmp(sb->s_type->name, "tracefs") ||
700 	    !strcmp(sb->s_type->name, "binder") ||
701 	    !strcmp(sb->s_type->name, "bpf") ||
702 	    !strcmp(sb->s_type->name, "pstore") ||
703 	    !strcmp(sb->s_type->name, "securityfs"))
704 		sbsec->flags |= SE_SBGENFS;
705 
706 	if (!strcmp(sb->s_type->name, "sysfs") ||
707 	    !strcmp(sb->s_type->name, "cgroup") ||
708 	    !strcmp(sb->s_type->name, "cgroup2"))
709 		sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
710 
711 	if (!sbsec->behavior) {
712 		/*
713 		 * Determine the labeling behavior to use for this
714 		 * filesystem type.
715 		 */
716 		rc = security_fs_use(sb);
717 		if (rc) {
718 			pr_warn("%s: security_fs_use(%s) returned %d\n",
719 					__func__, sb->s_type->name, rc);
720 			goto out;
721 		}
722 	}
723 
724 	/*
725 	 * If this is a user namespace mount and the filesystem type is not
726 	 * explicitly whitelisted, then no contexts are allowed on the command
727 	 * line and security labels must be ignored.
728 	 */
729 	if (sb->s_user_ns != &init_user_ns &&
730 	    strcmp(sb->s_type->name, "tmpfs") &&
731 	    strcmp(sb->s_type->name, "ramfs") &&
732 	    strcmp(sb->s_type->name, "devpts") &&
733 	    strcmp(sb->s_type->name, "overlay")) {
734 		if (context_sid || fscontext_sid || rootcontext_sid ||
735 		    defcontext_sid) {
736 			rc = -EACCES;
737 			goto out;
738 		}
739 		if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
740 			sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
741 			rc = security_transition_sid(current_sid(),
742 						     current_sid(),
743 						     SECCLASS_FILE, NULL,
744 						     &sbsec->mntpoint_sid);
745 			if (rc)
746 				goto out;
747 		}
748 		goto out_set_opts;
749 	}
750 
751 	/* sets the context of the superblock for the fs being mounted. */
752 	if (fscontext_sid) {
753 		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
754 		if (rc)
755 			goto out;
756 
757 		sbsec->sid = fscontext_sid;
758 	}
759 
760 	/*
761 	 * Switch to using mount point labeling behavior.
762 	 * sets the label used on all file below the mountpoint, and will set
763 	 * the superblock context if not already set.
764 	 */
765 	if (sbsec->flags & SE_SBNATIVE) {
766 		/*
767 		 * This means we are initializing a superblock that has been
768 		 * mounted before the SELinux was initialized and the
769 		 * filesystem requested native labeling. We had already
770 		 * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags
771 		 * in the original mount attempt, so now we just need to set
772 		 * the SECURITY_FS_USE_NATIVE behavior.
773 		 */
774 		sbsec->behavior = SECURITY_FS_USE_NATIVE;
775 	} else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
776 		sbsec->behavior = SECURITY_FS_USE_NATIVE;
777 		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
778 	}
779 
780 	if (context_sid) {
781 		if (!fscontext_sid) {
782 			rc = may_context_mount_sb_relabel(context_sid, sbsec,
783 							  cred);
784 			if (rc)
785 				goto out;
786 			sbsec->sid = context_sid;
787 		} else {
788 			rc = may_context_mount_inode_relabel(context_sid, sbsec,
789 							     cred);
790 			if (rc)
791 				goto out;
792 		}
793 		if (!rootcontext_sid)
794 			rootcontext_sid = context_sid;
795 
796 		sbsec->mntpoint_sid = context_sid;
797 		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
798 	}
799 
800 	if (rootcontext_sid) {
801 		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
802 						     cred);
803 		if (rc)
804 			goto out;
805 
806 		root_isec->sid = rootcontext_sid;
807 		root_isec->initialized = LABEL_INITIALIZED;
808 	}
809 
810 	if (defcontext_sid) {
811 		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
812 			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
813 			rc = -EINVAL;
814 			pr_warn("SELinux: defcontext option is "
815 			       "invalid for this filesystem type\n");
816 			goto out;
817 		}
818 
819 		if (defcontext_sid != sbsec->def_sid) {
820 			rc = may_context_mount_inode_relabel(defcontext_sid,
821 							     sbsec, cred);
822 			if (rc)
823 				goto out;
824 		}
825 
826 		sbsec->def_sid = defcontext_sid;
827 	}
828 
829 out_set_opts:
830 	rc = sb_finish_set_opts(sb);
831 out:
832 	mutex_unlock(&sbsec->lock);
833 	return rc;
834 out_double_mount:
835 	rc = -EINVAL;
836 	pr_warn("SELinux: mount invalid.  Same superblock, different "
837 	       "security settings for (dev %s, type %s)\n", sb->s_id,
838 	       sb->s_type->name);
839 	goto out;
840 }
841 
842 static int selinux_cmp_sb_context(const struct super_block *oldsb,
843 				    const struct super_block *newsb)
844 {
845 	struct superblock_security_struct *old = selinux_superblock(oldsb);
846 	struct superblock_security_struct *new = selinux_superblock(newsb);
847 	char oldflags = old->flags & SE_MNTMASK;
848 	char newflags = new->flags & SE_MNTMASK;
849 
850 	if (oldflags != newflags)
851 		goto mismatch;
852 	if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
853 		goto mismatch;
854 	if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
855 		goto mismatch;
856 	if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
857 		goto mismatch;
858 	if (oldflags & ROOTCONTEXT_MNT) {
859 		struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
860 		struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
861 		if (oldroot->sid != newroot->sid)
862 			goto mismatch;
863 	}
864 	return 0;
865 mismatch:
866 	pr_warn("SELinux: mount invalid.  Same superblock, "
867 			    "different security settings for (dev %s, "
868 			    "type %s)\n", newsb->s_id, newsb->s_type->name);
869 	return -EBUSY;
870 }
871 
872 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
873 					struct super_block *newsb,
874 					unsigned long kern_flags,
875 					unsigned long *set_kern_flags)
876 {
877 	int rc = 0;
878 	const struct superblock_security_struct *oldsbsec =
879 						selinux_superblock(oldsb);
880 	struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
881 
882 	int set_fscontext =	(oldsbsec->flags & FSCONTEXT_MNT);
883 	int set_context =	(oldsbsec->flags & CONTEXT_MNT);
884 	int set_rootcontext =	(oldsbsec->flags & ROOTCONTEXT_MNT);
885 
886 	/*
887 	 * Specifying internal flags without providing a place to
888 	 * place the results is not allowed.
889 	 */
890 	if (kern_flags && !set_kern_flags)
891 		return -EINVAL;
892 
893 	mutex_lock(&newsbsec->lock);
894 
895 	/*
896 	 * if the parent was able to be mounted it clearly had no special lsm
897 	 * mount options.  thus we can safely deal with this superblock later
898 	 */
899 	if (!selinux_initialized()) {
900 		if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
901 			newsbsec->flags |= SE_SBNATIVE;
902 			*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
903 		}
904 		goto out;
905 	}
906 
907 	/* how can we clone if the old one wasn't set up?? */
908 	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
909 
910 	/* if fs is reusing a sb, make sure that the contexts match */
911 	if (newsbsec->flags & SE_SBINITIALIZED) {
912 		mutex_unlock(&newsbsec->lock);
913 		if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
914 			*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
915 		return selinux_cmp_sb_context(oldsb, newsb);
916 	}
917 
918 	newsbsec->flags = oldsbsec->flags;
919 
920 	newsbsec->sid = oldsbsec->sid;
921 	newsbsec->def_sid = oldsbsec->def_sid;
922 	newsbsec->behavior = oldsbsec->behavior;
923 
924 	if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
925 		!(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
926 		rc = security_fs_use(newsb);
927 		if (rc)
928 			goto out;
929 	}
930 
931 	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
932 		newsbsec->behavior = SECURITY_FS_USE_NATIVE;
933 		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
934 	}
935 
936 	if (set_context) {
937 		u32 sid = oldsbsec->mntpoint_sid;
938 
939 		if (!set_fscontext)
940 			newsbsec->sid = sid;
941 		if (!set_rootcontext) {
942 			struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
943 			newisec->sid = sid;
944 		}
945 		newsbsec->mntpoint_sid = sid;
946 	}
947 	if (set_rootcontext) {
948 		const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
949 		struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
950 
951 		newisec->sid = oldisec->sid;
952 	}
953 
954 	sb_finish_set_opts(newsb);
955 out:
956 	mutex_unlock(&newsbsec->lock);
957 	return rc;
958 }
959 
960 /*
961  * NOTE: the caller is responsible for freeing the memory even if on error.
962  */
963 static int selinux_add_opt(int token, const char *s, void **mnt_opts)
964 {
965 	struct selinux_mnt_opts *opts = *mnt_opts;
966 	u32 *dst_sid;
967 	int rc;
968 
969 	if (token == Opt_seclabel)
970 		/* eaten and completely ignored */
971 		return 0;
972 	if (!s)
973 		return -EINVAL;
974 
975 	if (!selinux_initialized()) {
976 		pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n");
977 		return -EINVAL;
978 	}
979 
980 	if (!opts) {
981 		opts = kzalloc(sizeof(*opts), GFP_KERNEL);
982 		if (!opts)
983 			return -ENOMEM;
984 		*mnt_opts = opts;
985 	}
986 
987 	switch (token) {
988 	case Opt_context:
989 		if (opts->context_sid || opts->defcontext_sid)
990 			goto err;
991 		dst_sid = &opts->context_sid;
992 		break;
993 	case Opt_fscontext:
994 		if (opts->fscontext_sid)
995 			goto err;
996 		dst_sid = &opts->fscontext_sid;
997 		break;
998 	case Opt_rootcontext:
999 		if (opts->rootcontext_sid)
1000 			goto err;
1001 		dst_sid = &opts->rootcontext_sid;
1002 		break;
1003 	case Opt_defcontext:
1004 		if (opts->context_sid || opts->defcontext_sid)
1005 			goto err;
1006 		dst_sid = &opts->defcontext_sid;
1007 		break;
1008 	default:
1009 		WARN_ON(1);
1010 		return -EINVAL;
1011 	}
1012 	rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL);
1013 	if (rc)
1014 		pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n",
1015 			s, rc);
1016 	return rc;
1017 
1018 err:
1019 	pr_warn(SEL_MOUNT_FAIL_MSG);
1020 	return -EINVAL;
1021 }
1022 
1023 static int show_sid(struct seq_file *m, u32 sid)
1024 {
1025 	char *context = NULL;
1026 	u32 len;
1027 	int rc;
1028 
1029 	rc = security_sid_to_context(sid, &context, &len);
1030 	if (!rc) {
1031 		bool has_comma = strchr(context, ',');
1032 
1033 		seq_putc(m, '=');
1034 		if (has_comma)
1035 			seq_putc(m, '\"');
1036 		seq_escape(m, context, "\"\n\\");
1037 		if (has_comma)
1038 			seq_putc(m, '\"');
1039 	}
1040 	kfree(context);
1041 	return rc;
1042 }
1043 
1044 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1045 {
1046 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
1047 	int rc;
1048 
1049 	if (!(sbsec->flags & SE_SBINITIALIZED))
1050 		return 0;
1051 
1052 	if (!selinux_initialized())
1053 		return 0;
1054 
1055 	if (sbsec->flags & FSCONTEXT_MNT) {
1056 		seq_putc(m, ',');
1057 		seq_puts(m, FSCONTEXT_STR);
1058 		rc = show_sid(m, sbsec->sid);
1059 		if (rc)
1060 			return rc;
1061 	}
1062 	if (sbsec->flags & CONTEXT_MNT) {
1063 		seq_putc(m, ',');
1064 		seq_puts(m, CONTEXT_STR);
1065 		rc = show_sid(m, sbsec->mntpoint_sid);
1066 		if (rc)
1067 			return rc;
1068 	}
1069 	if (sbsec->flags & DEFCONTEXT_MNT) {
1070 		seq_putc(m, ',');
1071 		seq_puts(m, DEFCONTEXT_STR);
1072 		rc = show_sid(m, sbsec->def_sid);
1073 		if (rc)
1074 			return rc;
1075 	}
1076 	if (sbsec->flags & ROOTCONTEXT_MNT) {
1077 		struct dentry *root = sb->s_root;
1078 		struct inode_security_struct *isec = backing_inode_security(root);
1079 		seq_putc(m, ',');
1080 		seq_puts(m, ROOTCONTEXT_STR);
1081 		rc = show_sid(m, isec->sid);
1082 		if (rc)
1083 			return rc;
1084 	}
1085 	if (sbsec->flags & SBLABEL_MNT) {
1086 		seq_putc(m, ',');
1087 		seq_puts(m, SECLABEL_STR);
1088 	}
1089 	return 0;
1090 }
1091 
1092 static inline u16 inode_mode_to_security_class(umode_t mode)
1093 {
1094 	switch (mode & S_IFMT) {
1095 	case S_IFSOCK:
1096 		return SECCLASS_SOCK_FILE;
1097 	case S_IFLNK:
1098 		return SECCLASS_LNK_FILE;
1099 	case S_IFREG:
1100 		return SECCLASS_FILE;
1101 	case S_IFBLK:
1102 		return SECCLASS_BLK_FILE;
1103 	case S_IFDIR:
1104 		return SECCLASS_DIR;
1105 	case S_IFCHR:
1106 		return SECCLASS_CHR_FILE;
1107 	case S_IFIFO:
1108 		return SECCLASS_FIFO_FILE;
1109 
1110 	}
1111 
1112 	return SECCLASS_FILE;
1113 }
1114 
1115 static inline int default_protocol_stream(int protocol)
1116 {
1117 	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1118 		protocol == IPPROTO_MPTCP);
1119 }
1120 
1121 static inline int default_protocol_dgram(int protocol)
1122 {
1123 	return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1124 }
1125 
1126 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1127 {
1128 	int extsockclass = selinux_policycap_extsockclass();
1129 
1130 	switch (family) {
1131 	case PF_UNIX:
1132 		switch (type) {
1133 		case SOCK_STREAM:
1134 		case SOCK_SEQPACKET:
1135 			return SECCLASS_UNIX_STREAM_SOCKET;
1136 		case SOCK_DGRAM:
1137 		case SOCK_RAW:
1138 			return SECCLASS_UNIX_DGRAM_SOCKET;
1139 		}
1140 		break;
1141 	case PF_INET:
1142 	case PF_INET6:
1143 		switch (type) {
1144 		case SOCK_STREAM:
1145 		case SOCK_SEQPACKET:
1146 			if (default_protocol_stream(protocol))
1147 				return SECCLASS_TCP_SOCKET;
1148 			else if (extsockclass && protocol == IPPROTO_SCTP)
1149 				return SECCLASS_SCTP_SOCKET;
1150 			else
1151 				return SECCLASS_RAWIP_SOCKET;
1152 		case SOCK_DGRAM:
1153 			if (default_protocol_dgram(protocol))
1154 				return SECCLASS_UDP_SOCKET;
1155 			else if (extsockclass && (protocol == IPPROTO_ICMP ||
1156 						  protocol == IPPROTO_ICMPV6))
1157 				return SECCLASS_ICMP_SOCKET;
1158 			else
1159 				return SECCLASS_RAWIP_SOCKET;
1160 		case SOCK_DCCP:
1161 			return SECCLASS_DCCP_SOCKET;
1162 		default:
1163 			return SECCLASS_RAWIP_SOCKET;
1164 		}
1165 		break;
1166 	case PF_NETLINK:
1167 		switch (protocol) {
1168 		case NETLINK_ROUTE:
1169 			return SECCLASS_NETLINK_ROUTE_SOCKET;
1170 		case NETLINK_SOCK_DIAG:
1171 			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1172 		case NETLINK_NFLOG:
1173 			return SECCLASS_NETLINK_NFLOG_SOCKET;
1174 		case NETLINK_XFRM:
1175 			return SECCLASS_NETLINK_XFRM_SOCKET;
1176 		case NETLINK_SELINUX:
1177 			return SECCLASS_NETLINK_SELINUX_SOCKET;
1178 		case NETLINK_ISCSI:
1179 			return SECCLASS_NETLINK_ISCSI_SOCKET;
1180 		case NETLINK_AUDIT:
1181 			return SECCLASS_NETLINK_AUDIT_SOCKET;
1182 		case NETLINK_FIB_LOOKUP:
1183 			return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1184 		case NETLINK_CONNECTOR:
1185 			return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1186 		case NETLINK_NETFILTER:
1187 			return SECCLASS_NETLINK_NETFILTER_SOCKET;
1188 		case NETLINK_DNRTMSG:
1189 			return SECCLASS_NETLINK_DNRT_SOCKET;
1190 		case NETLINK_KOBJECT_UEVENT:
1191 			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1192 		case NETLINK_GENERIC:
1193 			return SECCLASS_NETLINK_GENERIC_SOCKET;
1194 		case NETLINK_SCSITRANSPORT:
1195 			return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1196 		case NETLINK_RDMA:
1197 			return SECCLASS_NETLINK_RDMA_SOCKET;
1198 		case NETLINK_CRYPTO:
1199 			return SECCLASS_NETLINK_CRYPTO_SOCKET;
1200 		default:
1201 			return SECCLASS_NETLINK_SOCKET;
1202 		}
1203 	case PF_PACKET:
1204 		return SECCLASS_PACKET_SOCKET;
1205 	case PF_KEY:
1206 		return SECCLASS_KEY_SOCKET;
1207 	case PF_APPLETALK:
1208 		return SECCLASS_APPLETALK_SOCKET;
1209 	}
1210 
1211 	if (extsockclass) {
1212 		switch (family) {
1213 		case PF_AX25:
1214 			return SECCLASS_AX25_SOCKET;
1215 		case PF_IPX:
1216 			return SECCLASS_IPX_SOCKET;
1217 		case PF_NETROM:
1218 			return SECCLASS_NETROM_SOCKET;
1219 		case PF_ATMPVC:
1220 			return SECCLASS_ATMPVC_SOCKET;
1221 		case PF_X25:
1222 			return SECCLASS_X25_SOCKET;
1223 		case PF_ROSE:
1224 			return SECCLASS_ROSE_SOCKET;
1225 		case PF_DECnet:
1226 			return SECCLASS_DECNET_SOCKET;
1227 		case PF_ATMSVC:
1228 			return SECCLASS_ATMSVC_SOCKET;
1229 		case PF_RDS:
1230 			return SECCLASS_RDS_SOCKET;
1231 		case PF_IRDA:
1232 			return SECCLASS_IRDA_SOCKET;
1233 		case PF_PPPOX:
1234 			return SECCLASS_PPPOX_SOCKET;
1235 		case PF_LLC:
1236 			return SECCLASS_LLC_SOCKET;
1237 		case PF_CAN:
1238 			return SECCLASS_CAN_SOCKET;
1239 		case PF_TIPC:
1240 			return SECCLASS_TIPC_SOCKET;
1241 		case PF_BLUETOOTH:
1242 			return SECCLASS_BLUETOOTH_SOCKET;
1243 		case PF_IUCV:
1244 			return SECCLASS_IUCV_SOCKET;
1245 		case PF_RXRPC:
1246 			return SECCLASS_RXRPC_SOCKET;
1247 		case PF_ISDN:
1248 			return SECCLASS_ISDN_SOCKET;
1249 		case PF_PHONET:
1250 			return SECCLASS_PHONET_SOCKET;
1251 		case PF_IEEE802154:
1252 			return SECCLASS_IEEE802154_SOCKET;
1253 		case PF_CAIF:
1254 			return SECCLASS_CAIF_SOCKET;
1255 		case PF_ALG:
1256 			return SECCLASS_ALG_SOCKET;
1257 		case PF_NFC:
1258 			return SECCLASS_NFC_SOCKET;
1259 		case PF_VSOCK:
1260 			return SECCLASS_VSOCK_SOCKET;
1261 		case PF_KCM:
1262 			return SECCLASS_KCM_SOCKET;
1263 		case PF_QIPCRTR:
1264 			return SECCLASS_QIPCRTR_SOCKET;
1265 		case PF_SMC:
1266 			return SECCLASS_SMC_SOCKET;
1267 		case PF_XDP:
1268 			return SECCLASS_XDP_SOCKET;
1269 		case PF_MCTP:
1270 			return SECCLASS_MCTP_SOCKET;
1271 #if PF_MAX > 46
1272 #error New address family defined, please update this function.
1273 #endif
1274 		}
1275 	}
1276 
1277 	return SECCLASS_SOCKET;
1278 }
1279 
1280 static int selinux_genfs_get_sid(struct dentry *dentry,
1281 				 u16 tclass,
1282 				 u16 flags,
1283 				 u32 *sid)
1284 {
1285 	int rc;
1286 	struct super_block *sb = dentry->d_sb;
1287 	char *buffer, *path;
1288 
1289 	buffer = (char *)__get_free_page(GFP_KERNEL);
1290 	if (!buffer)
1291 		return -ENOMEM;
1292 
1293 	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1294 	if (IS_ERR(path))
1295 		rc = PTR_ERR(path);
1296 	else {
1297 		if (flags & SE_SBPROC) {
1298 			/* each process gets a /proc/PID/ entry. Strip off the
1299 			 * PID part to get a valid selinux labeling.
1300 			 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1301 			while (path[1] >= '0' && path[1] <= '9') {
1302 				path[1] = '/';
1303 				path++;
1304 			}
1305 		}
1306 		rc = security_genfs_sid(sb->s_type->name,
1307 					path, tclass, sid);
1308 		if (rc == -ENOENT) {
1309 			/* No match in policy, mark as unlabeled. */
1310 			*sid = SECINITSID_UNLABELED;
1311 			rc = 0;
1312 		}
1313 	}
1314 	free_page((unsigned long)buffer);
1315 	return rc;
1316 }
1317 
1318 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1319 				  u32 def_sid, u32 *sid)
1320 {
1321 #define INITCONTEXTLEN 255
1322 	char *context;
1323 	unsigned int len;
1324 	int rc;
1325 
1326 	len = INITCONTEXTLEN;
1327 	context = kmalloc(len + 1, GFP_NOFS);
1328 	if (!context)
1329 		return -ENOMEM;
1330 
1331 	context[len] = '\0';
1332 	rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1333 	if (rc == -ERANGE) {
1334 		kfree(context);
1335 
1336 		/* Need a larger buffer.  Query for the right size. */
1337 		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1338 		if (rc < 0)
1339 			return rc;
1340 
1341 		len = rc;
1342 		context = kmalloc(len + 1, GFP_NOFS);
1343 		if (!context)
1344 			return -ENOMEM;
1345 
1346 		context[len] = '\0';
1347 		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1348 				    context, len);
1349 	}
1350 	if (rc < 0) {
1351 		kfree(context);
1352 		if (rc != -ENODATA) {
1353 			pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
1354 				__func__, -rc, inode->i_sb->s_id, inode->i_ino);
1355 			return rc;
1356 		}
1357 		*sid = def_sid;
1358 		return 0;
1359 	}
1360 
1361 	rc = security_context_to_sid_default(context, rc, sid,
1362 					     def_sid, GFP_NOFS);
1363 	if (rc) {
1364 		char *dev = inode->i_sb->s_id;
1365 		unsigned long ino = inode->i_ino;
1366 
1367 		if (rc == -EINVAL) {
1368 			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",
1369 					      ino, dev, context);
1370 		} else {
1371 			pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1372 				__func__, context, -rc, dev, ino);
1373 		}
1374 	}
1375 	kfree(context);
1376 	return 0;
1377 }
1378 
1379 /* The inode's security attributes must be initialized before first use. */
1380 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1381 {
1382 	struct superblock_security_struct *sbsec = NULL;
1383 	struct inode_security_struct *isec = selinux_inode(inode);
1384 	u32 task_sid, sid = 0;
1385 	u16 sclass;
1386 	struct dentry *dentry;
1387 	int rc = 0;
1388 
1389 	if (isec->initialized == LABEL_INITIALIZED)
1390 		return 0;
1391 
1392 	spin_lock(&isec->lock);
1393 	if (isec->initialized == LABEL_INITIALIZED)
1394 		goto out_unlock;
1395 
1396 	if (isec->sclass == SECCLASS_FILE)
1397 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
1398 
1399 	sbsec = selinux_superblock(inode->i_sb);
1400 	if (!(sbsec->flags & SE_SBINITIALIZED)) {
1401 		/* Defer initialization until selinux_complete_init,
1402 		   after the initial policy is loaded and the security
1403 		   server is ready to handle calls. */
1404 		spin_lock(&sbsec->isec_lock);
1405 		if (list_empty(&isec->list))
1406 			list_add(&isec->list, &sbsec->isec_head);
1407 		spin_unlock(&sbsec->isec_lock);
1408 		goto out_unlock;
1409 	}
1410 
1411 	sclass = isec->sclass;
1412 	task_sid = isec->task_sid;
1413 	sid = isec->sid;
1414 	isec->initialized = LABEL_PENDING;
1415 	spin_unlock(&isec->lock);
1416 
1417 	switch (sbsec->behavior) {
1418 	/*
1419 	 * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels
1420 	 * via xattr when called from delayed_superblock_init().
1421 	 */
1422 	case SECURITY_FS_USE_NATIVE:
1423 	case SECURITY_FS_USE_XATTR:
1424 		if (!(inode->i_opflags & IOP_XATTR)) {
1425 			sid = sbsec->def_sid;
1426 			break;
1427 		}
1428 		/* Need a dentry, since the xattr API requires one.
1429 		   Life would be simpler if we could just pass the inode. */
1430 		if (opt_dentry) {
1431 			/* Called from d_instantiate or d_splice_alias. */
1432 			dentry = dget(opt_dentry);
1433 		} else {
1434 			/*
1435 			 * Called from selinux_complete_init, try to find a dentry.
1436 			 * Some filesystems really want a connected one, so try
1437 			 * that first.  We could split SECURITY_FS_USE_XATTR in
1438 			 * two, depending upon that...
1439 			 */
1440 			dentry = d_find_alias(inode);
1441 			if (!dentry)
1442 				dentry = d_find_any_alias(inode);
1443 		}
1444 		if (!dentry) {
1445 			/*
1446 			 * this is can be hit on boot when a file is accessed
1447 			 * before the policy is loaded.  When we load policy we
1448 			 * may find inodes that have no dentry on the
1449 			 * sbsec->isec_head list.  No reason to complain as these
1450 			 * will get fixed up the next time we go through
1451 			 * inode_doinit with a dentry, before these inodes could
1452 			 * be used again by userspace.
1453 			 */
1454 			goto out_invalid;
1455 		}
1456 
1457 		rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1458 					    &sid);
1459 		dput(dentry);
1460 		if (rc)
1461 			goto out;
1462 		break;
1463 	case SECURITY_FS_USE_TASK:
1464 		sid = task_sid;
1465 		break;
1466 	case SECURITY_FS_USE_TRANS:
1467 		/* Default to the fs SID. */
1468 		sid = sbsec->sid;
1469 
1470 		/* Try to obtain a transition SID. */
1471 		rc = security_transition_sid(task_sid, sid,
1472 					     sclass, NULL, &sid);
1473 		if (rc)
1474 			goto out;
1475 		break;
1476 	case SECURITY_FS_USE_MNTPOINT:
1477 		sid = sbsec->mntpoint_sid;
1478 		break;
1479 	default:
1480 		/* Default to the fs superblock SID. */
1481 		sid = sbsec->sid;
1482 
1483 		if ((sbsec->flags & SE_SBGENFS) &&
1484 		     (!S_ISLNK(inode->i_mode) ||
1485 		      selinux_policycap_genfs_seclabel_symlinks())) {
1486 			/* We must have a dentry to determine the label on
1487 			 * procfs inodes */
1488 			if (opt_dentry) {
1489 				/* Called from d_instantiate or
1490 				 * d_splice_alias. */
1491 				dentry = dget(opt_dentry);
1492 			} else {
1493 				/* Called from selinux_complete_init, try to
1494 				 * find a dentry.  Some filesystems really want
1495 				 * a connected one, so try that first.
1496 				 */
1497 				dentry = d_find_alias(inode);
1498 				if (!dentry)
1499 					dentry = d_find_any_alias(inode);
1500 			}
1501 			/*
1502 			 * This can be hit on boot when a file is accessed
1503 			 * before the policy is loaded.  When we load policy we
1504 			 * may find inodes that have no dentry on the
1505 			 * sbsec->isec_head list.  No reason to complain as
1506 			 * these will get fixed up the next time we go through
1507 			 * inode_doinit() with a dentry, before these inodes
1508 			 * could be used again by userspace.
1509 			 */
1510 			if (!dentry)
1511 				goto out_invalid;
1512 			rc = selinux_genfs_get_sid(dentry, sclass,
1513 						   sbsec->flags, &sid);
1514 			if (rc) {
1515 				dput(dentry);
1516 				goto out;
1517 			}
1518 
1519 			if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1520 			    (inode->i_opflags & IOP_XATTR)) {
1521 				rc = inode_doinit_use_xattr(inode, dentry,
1522 							    sid, &sid);
1523 				if (rc) {
1524 					dput(dentry);
1525 					goto out;
1526 				}
1527 			}
1528 			dput(dentry);
1529 		}
1530 		break;
1531 	}
1532 
1533 out:
1534 	spin_lock(&isec->lock);
1535 	if (isec->initialized == LABEL_PENDING) {
1536 		if (rc) {
1537 			isec->initialized = LABEL_INVALID;
1538 			goto out_unlock;
1539 		}
1540 		isec->initialized = LABEL_INITIALIZED;
1541 		isec->sid = sid;
1542 	}
1543 
1544 out_unlock:
1545 	spin_unlock(&isec->lock);
1546 	return rc;
1547 
1548 out_invalid:
1549 	spin_lock(&isec->lock);
1550 	if (isec->initialized == LABEL_PENDING) {
1551 		isec->initialized = LABEL_INVALID;
1552 		isec->sid = sid;
1553 	}
1554 	spin_unlock(&isec->lock);
1555 	return 0;
1556 }
1557 
1558 /* Convert a Linux signal to an access vector. */
1559 static inline u32 signal_to_av(int sig)
1560 {
1561 	u32 perm = 0;
1562 
1563 	switch (sig) {
1564 	case SIGCHLD:
1565 		/* Commonly granted from child to parent. */
1566 		perm = PROCESS__SIGCHLD;
1567 		break;
1568 	case SIGKILL:
1569 		/* Cannot be caught or ignored */
1570 		perm = PROCESS__SIGKILL;
1571 		break;
1572 	case SIGSTOP:
1573 		/* Cannot be caught or ignored */
1574 		perm = PROCESS__SIGSTOP;
1575 		break;
1576 	default:
1577 		/* All other signals. */
1578 		perm = PROCESS__SIGNAL;
1579 		break;
1580 	}
1581 
1582 	return perm;
1583 }
1584 
1585 #if CAP_LAST_CAP > 63
1586 #error Fix SELinux to handle capabilities > 63.
1587 #endif
1588 
1589 /* Check whether a task is allowed to use a capability. */
1590 static int cred_has_capability(const struct cred *cred,
1591 			       int cap, unsigned int opts, bool initns)
1592 {
1593 	struct common_audit_data ad;
1594 	struct av_decision avd;
1595 	u16 sclass;
1596 	u32 sid = cred_sid(cred);
1597 	u32 av = CAP_TO_MASK(cap);
1598 	int rc;
1599 
1600 	ad.type = LSM_AUDIT_DATA_CAP;
1601 	ad.u.cap = cap;
1602 
1603 	switch (CAP_TO_INDEX(cap)) {
1604 	case 0:
1605 		sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1606 		break;
1607 	case 1:
1608 		sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1609 		break;
1610 	default:
1611 		pr_err("SELinux:  out of range capability %d\n", cap);
1612 		BUG();
1613 		return -EINVAL;
1614 	}
1615 
1616 	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1617 	if (!(opts & CAP_OPT_NOAUDIT)) {
1618 		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1619 		if (rc2)
1620 			return rc2;
1621 	}
1622 	return rc;
1623 }
1624 
1625 /* Check whether a task has a particular permission to an inode.
1626    The 'adp' parameter is optional and allows other audit
1627    data to be passed (e.g. the dentry). */
1628 static int inode_has_perm(const struct cred *cred,
1629 			  struct inode *inode,
1630 			  u32 perms,
1631 			  struct common_audit_data *adp)
1632 {
1633 	struct inode_security_struct *isec;
1634 	u32 sid;
1635 
1636 	validate_creds(cred);
1637 
1638 	if (unlikely(IS_PRIVATE(inode)))
1639 		return 0;
1640 
1641 	sid = cred_sid(cred);
1642 	isec = selinux_inode(inode);
1643 
1644 	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1645 }
1646 
1647 /* Same as inode_has_perm, but pass explicit audit data containing
1648    the dentry to help the auditing code to more easily generate the
1649    pathname if needed. */
1650 static inline int dentry_has_perm(const struct cred *cred,
1651 				  struct dentry *dentry,
1652 				  u32 av)
1653 {
1654 	struct inode *inode = d_backing_inode(dentry);
1655 	struct common_audit_data ad;
1656 
1657 	ad.type = LSM_AUDIT_DATA_DENTRY;
1658 	ad.u.dentry = dentry;
1659 	__inode_security_revalidate(inode, dentry, true);
1660 	return inode_has_perm(cred, inode, av, &ad);
1661 }
1662 
1663 /* Same as inode_has_perm, but pass explicit audit data containing
1664    the path to help the auditing code to more easily generate the
1665    pathname if needed. */
1666 static inline int path_has_perm(const struct cred *cred,
1667 				const struct path *path,
1668 				u32 av)
1669 {
1670 	struct inode *inode = d_backing_inode(path->dentry);
1671 	struct common_audit_data ad;
1672 
1673 	ad.type = LSM_AUDIT_DATA_PATH;
1674 	ad.u.path = *path;
1675 	__inode_security_revalidate(inode, path->dentry, true);
1676 	return inode_has_perm(cred, inode, av, &ad);
1677 }
1678 
1679 /* Same as path_has_perm, but uses the inode from the file struct. */
1680 static inline int file_path_has_perm(const struct cred *cred,
1681 				     struct file *file,
1682 				     u32 av)
1683 {
1684 	struct common_audit_data ad;
1685 
1686 	ad.type = LSM_AUDIT_DATA_FILE;
1687 	ad.u.file = file;
1688 	return inode_has_perm(cred, file_inode(file), av, &ad);
1689 }
1690 
1691 #ifdef CONFIG_BPF_SYSCALL
1692 static int bpf_fd_pass(struct file *file, u32 sid);
1693 #endif
1694 
1695 /* Check whether a task can use an open file descriptor to
1696    access an inode in a given way.  Check access to the
1697    descriptor itself, and then use dentry_has_perm to
1698    check a particular permission to the file.
1699    Access to the descriptor is implicitly granted if it
1700    has the same SID as the process.  If av is zero, then
1701    access to the file is not checked, e.g. for cases
1702    where only the descriptor is affected like seek. */
1703 static int file_has_perm(const struct cred *cred,
1704 			 struct file *file,
1705 			 u32 av)
1706 {
1707 	struct file_security_struct *fsec = selinux_file(file);
1708 	struct inode *inode = file_inode(file);
1709 	struct common_audit_data ad;
1710 	u32 sid = cred_sid(cred);
1711 	int rc;
1712 
1713 	ad.type = LSM_AUDIT_DATA_FILE;
1714 	ad.u.file = file;
1715 
1716 	if (sid != fsec->sid) {
1717 		rc = avc_has_perm(sid, fsec->sid,
1718 				  SECCLASS_FD,
1719 				  FD__USE,
1720 				  &ad);
1721 		if (rc)
1722 			goto out;
1723 	}
1724 
1725 #ifdef CONFIG_BPF_SYSCALL
1726 	rc = bpf_fd_pass(file, cred_sid(cred));
1727 	if (rc)
1728 		return rc;
1729 #endif
1730 
1731 	/* av is zero if only checking access to the descriptor. */
1732 	rc = 0;
1733 	if (av)
1734 		rc = inode_has_perm(cred, inode, av, &ad);
1735 
1736 out:
1737 	return rc;
1738 }
1739 
1740 /*
1741  * Determine the label for an inode that might be unioned.
1742  */
1743 static int
1744 selinux_determine_inode_label(const struct task_security_struct *tsec,
1745 				 struct inode *dir,
1746 				 const struct qstr *name, u16 tclass,
1747 				 u32 *_new_isid)
1748 {
1749 	const struct superblock_security_struct *sbsec =
1750 						selinux_superblock(dir->i_sb);
1751 
1752 	if ((sbsec->flags & SE_SBINITIALIZED) &&
1753 	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1754 		*_new_isid = sbsec->mntpoint_sid;
1755 	} else if ((sbsec->flags & SBLABEL_MNT) &&
1756 		   tsec->create_sid) {
1757 		*_new_isid = tsec->create_sid;
1758 	} else {
1759 		const struct inode_security_struct *dsec = inode_security(dir);
1760 		return security_transition_sid(tsec->sid,
1761 					       dsec->sid, tclass,
1762 					       name, _new_isid);
1763 	}
1764 
1765 	return 0;
1766 }
1767 
1768 /* Check whether a task can create a file. */
1769 static int may_create(struct inode *dir,
1770 		      struct dentry *dentry,
1771 		      u16 tclass)
1772 {
1773 	const struct task_security_struct *tsec = selinux_cred(current_cred());
1774 	struct inode_security_struct *dsec;
1775 	struct superblock_security_struct *sbsec;
1776 	u32 sid, newsid;
1777 	struct common_audit_data ad;
1778 	int rc;
1779 
1780 	dsec = inode_security(dir);
1781 	sbsec = selinux_superblock(dir->i_sb);
1782 
1783 	sid = tsec->sid;
1784 
1785 	ad.type = LSM_AUDIT_DATA_DENTRY;
1786 	ad.u.dentry = dentry;
1787 
1788 	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1789 			  DIR__ADD_NAME | DIR__SEARCH,
1790 			  &ad);
1791 	if (rc)
1792 		return rc;
1793 
1794 	rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1795 					   &newsid);
1796 	if (rc)
1797 		return rc;
1798 
1799 	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1800 	if (rc)
1801 		return rc;
1802 
1803 	return avc_has_perm(newsid, sbsec->sid,
1804 			    SECCLASS_FILESYSTEM,
1805 			    FILESYSTEM__ASSOCIATE, &ad);
1806 }
1807 
1808 #define MAY_LINK	0
1809 #define MAY_UNLINK	1
1810 #define MAY_RMDIR	2
1811 
1812 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1813 static int may_link(struct inode *dir,
1814 		    struct dentry *dentry,
1815 		    int kind)
1816 
1817 {
1818 	struct inode_security_struct *dsec, *isec;
1819 	struct common_audit_data ad;
1820 	u32 sid = current_sid();
1821 	u32 av;
1822 	int rc;
1823 
1824 	dsec = inode_security(dir);
1825 	isec = backing_inode_security(dentry);
1826 
1827 	ad.type = LSM_AUDIT_DATA_DENTRY;
1828 	ad.u.dentry = dentry;
1829 
1830 	av = DIR__SEARCH;
1831 	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1832 	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1833 	if (rc)
1834 		return rc;
1835 
1836 	switch (kind) {
1837 	case MAY_LINK:
1838 		av = FILE__LINK;
1839 		break;
1840 	case MAY_UNLINK:
1841 		av = FILE__UNLINK;
1842 		break;
1843 	case MAY_RMDIR:
1844 		av = DIR__RMDIR;
1845 		break;
1846 	default:
1847 		pr_warn("SELinux: %s:  unrecognized kind %d\n",
1848 			__func__, kind);
1849 		return 0;
1850 	}
1851 
1852 	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1853 	return rc;
1854 }
1855 
1856 static inline int may_rename(struct inode *old_dir,
1857 			     struct dentry *old_dentry,
1858 			     struct inode *new_dir,
1859 			     struct dentry *new_dentry)
1860 {
1861 	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1862 	struct common_audit_data ad;
1863 	u32 sid = current_sid();
1864 	u32 av;
1865 	int old_is_dir, new_is_dir;
1866 	int rc;
1867 
1868 	old_dsec = inode_security(old_dir);
1869 	old_isec = backing_inode_security(old_dentry);
1870 	old_is_dir = d_is_dir(old_dentry);
1871 	new_dsec = inode_security(new_dir);
1872 
1873 	ad.type = LSM_AUDIT_DATA_DENTRY;
1874 
1875 	ad.u.dentry = old_dentry;
1876 	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1877 			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1878 	if (rc)
1879 		return rc;
1880 	rc = avc_has_perm(sid, old_isec->sid,
1881 			  old_isec->sclass, FILE__RENAME, &ad);
1882 	if (rc)
1883 		return rc;
1884 	if (old_is_dir && new_dir != old_dir) {
1885 		rc = avc_has_perm(sid, old_isec->sid,
1886 				  old_isec->sclass, DIR__REPARENT, &ad);
1887 		if (rc)
1888 			return rc;
1889 	}
1890 
1891 	ad.u.dentry = new_dentry;
1892 	av = DIR__ADD_NAME | DIR__SEARCH;
1893 	if (d_is_positive(new_dentry))
1894 		av |= DIR__REMOVE_NAME;
1895 	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1896 	if (rc)
1897 		return rc;
1898 	if (d_is_positive(new_dentry)) {
1899 		new_isec = backing_inode_security(new_dentry);
1900 		new_is_dir = d_is_dir(new_dentry);
1901 		rc = avc_has_perm(sid, new_isec->sid,
1902 				  new_isec->sclass,
1903 				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1904 		if (rc)
1905 			return rc;
1906 	}
1907 
1908 	return 0;
1909 }
1910 
1911 /* Check whether a task can perform a filesystem operation. */
1912 static int superblock_has_perm(const struct cred *cred,
1913 			       struct super_block *sb,
1914 			       u32 perms,
1915 			       struct common_audit_data *ad)
1916 {
1917 	struct superblock_security_struct *sbsec;
1918 	u32 sid = cred_sid(cred);
1919 
1920 	sbsec = selinux_superblock(sb);
1921 	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1922 }
1923 
1924 /* Convert a Linux mode and permission mask to an access vector. */
1925 static inline u32 file_mask_to_av(int mode, int mask)
1926 {
1927 	u32 av = 0;
1928 
1929 	if (!S_ISDIR(mode)) {
1930 		if (mask & MAY_EXEC)
1931 			av |= FILE__EXECUTE;
1932 		if (mask & MAY_READ)
1933 			av |= FILE__READ;
1934 
1935 		if (mask & MAY_APPEND)
1936 			av |= FILE__APPEND;
1937 		else if (mask & MAY_WRITE)
1938 			av |= FILE__WRITE;
1939 
1940 	} else {
1941 		if (mask & MAY_EXEC)
1942 			av |= DIR__SEARCH;
1943 		if (mask & MAY_WRITE)
1944 			av |= DIR__WRITE;
1945 		if (mask & MAY_READ)
1946 			av |= DIR__READ;
1947 	}
1948 
1949 	return av;
1950 }
1951 
1952 /* Convert a Linux file to an access vector. */
1953 static inline u32 file_to_av(struct file *file)
1954 {
1955 	u32 av = 0;
1956 
1957 	if (file->f_mode & FMODE_READ)
1958 		av |= FILE__READ;
1959 	if (file->f_mode & FMODE_WRITE) {
1960 		if (file->f_flags & O_APPEND)
1961 			av |= FILE__APPEND;
1962 		else
1963 			av |= FILE__WRITE;
1964 	}
1965 	if (!av) {
1966 		/*
1967 		 * Special file opened with flags 3 for ioctl-only use.
1968 		 */
1969 		av = FILE__IOCTL;
1970 	}
1971 
1972 	return av;
1973 }
1974 
1975 /*
1976  * Convert a file to an access vector and include the correct
1977  * open permission.
1978  */
1979 static inline u32 open_file_to_av(struct file *file)
1980 {
1981 	u32 av = file_to_av(file);
1982 	struct inode *inode = file_inode(file);
1983 
1984 	if (selinux_policycap_openperm() &&
1985 	    inode->i_sb->s_magic != SOCKFS_MAGIC)
1986 		av |= FILE__OPEN;
1987 
1988 	return av;
1989 }
1990 
1991 /* Hook functions begin here. */
1992 
1993 static int selinux_binder_set_context_mgr(const struct cred *mgr)
1994 {
1995 	return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER,
1996 			    BINDER__SET_CONTEXT_MGR, NULL);
1997 }
1998 
1999 static int selinux_binder_transaction(const struct cred *from,
2000 				      const struct cred *to)
2001 {
2002 	u32 mysid = current_sid();
2003 	u32 fromsid = cred_sid(from);
2004 	u32 tosid = cred_sid(to);
2005 	int rc;
2006 
2007 	if (mysid != fromsid) {
2008 		rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2009 				  BINDER__IMPERSONATE, NULL);
2010 		if (rc)
2011 			return rc;
2012 	}
2013 
2014 	return avc_has_perm(fromsid, tosid,
2015 			    SECCLASS_BINDER, BINDER__CALL, NULL);
2016 }
2017 
2018 static int selinux_binder_transfer_binder(const struct cred *from,
2019 					  const struct cred *to)
2020 {
2021 	return avc_has_perm(cred_sid(from), cred_sid(to),
2022 			    SECCLASS_BINDER, BINDER__TRANSFER,
2023 			    NULL);
2024 }
2025 
2026 static int selinux_binder_transfer_file(const struct cred *from,
2027 					const struct cred *to,
2028 					struct file *file)
2029 {
2030 	u32 sid = cred_sid(to);
2031 	struct file_security_struct *fsec = selinux_file(file);
2032 	struct dentry *dentry = file->f_path.dentry;
2033 	struct inode_security_struct *isec;
2034 	struct common_audit_data ad;
2035 	int rc;
2036 
2037 	ad.type = LSM_AUDIT_DATA_PATH;
2038 	ad.u.path = file->f_path;
2039 
2040 	if (sid != fsec->sid) {
2041 		rc = avc_has_perm(sid, fsec->sid,
2042 				  SECCLASS_FD,
2043 				  FD__USE,
2044 				  &ad);
2045 		if (rc)
2046 			return rc;
2047 	}
2048 
2049 #ifdef CONFIG_BPF_SYSCALL
2050 	rc = bpf_fd_pass(file, sid);
2051 	if (rc)
2052 		return rc;
2053 #endif
2054 
2055 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2056 		return 0;
2057 
2058 	isec = backing_inode_security(dentry);
2059 	return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2060 			    &ad);
2061 }
2062 
2063 static int selinux_ptrace_access_check(struct task_struct *child,
2064 				       unsigned int mode)
2065 {
2066 	u32 sid = current_sid();
2067 	u32 csid = task_sid_obj(child);
2068 
2069 	if (mode & PTRACE_MODE_READ)
2070 		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ,
2071 				NULL);
2072 
2073 	return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE,
2074 			NULL);
2075 }
2076 
2077 static int selinux_ptrace_traceme(struct task_struct *parent)
2078 {
2079 	return avc_has_perm(task_sid_obj(parent), task_sid_obj(current),
2080 			    SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2081 }
2082 
2083 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2084 			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
2085 {
2086 	return avc_has_perm(current_sid(), task_sid_obj(target),
2087 			SECCLASS_PROCESS, PROCESS__GETCAP, NULL);
2088 }
2089 
2090 static int selinux_capset(struct cred *new, const struct cred *old,
2091 			  const kernel_cap_t *effective,
2092 			  const kernel_cap_t *inheritable,
2093 			  const kernel_cap_t *permitted)
2094 {
2095 	return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2096 			    PROCESS__SETCAP, NULL);
2097 }
2098 
2099 /*
2100  * (This comment used to live with the selinux_task_setuid hook,
2101  * which was removed).
2102  *
2103  * Since setuid only affects the current process, and since the SELinux
2104  * controls are not based on the Linux identity attributes, SELinux does not
2105  * need to control this operation.  However, SELinux does control the use of
2106  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2107  */
2108 
2109 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2110 			   int cap, unsigned int opts)
2111 {
2112 	return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2113 }
2114 
2115 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2116 {
2117 	const struct cred *cred = current_cred();
2118 	int rc = 0;
2119 
2120 	if (!sb)
2121 		return 0;
2122 
2123 	switch (cmds) {
2124 	case Q_SYNC:
2125 	case Q_QUOTAON:
2126 	case Q_QUOTAOFF:
2127 	case Q_SETINFO:
2128 	case Q_SETQUOTA:
2129 	case Q_XQUOTAOFF:
2130 	case Q_XQUOTAON:
2131 	case Q_XSETQLIM:
2132 		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2133 		break;
2134 	case Q_GETFMT:
2135 	case Q_GETINFO:
2136 	case Q_GETQUOTA:
2137 	case Q_XGETQUOTA:
2138 	case Q_XGETQSTAT:
2139 	case Q_XGETQSTATV:
2140 	case Q_XGETNEXTQUOTA:
2141 		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2142 		break;
2143 	default:
2144 		rc = 0;  /* let the kernel handle invalid cmds */
2145 		break;
2146 	}
2147 	return rc;
2148 }
2149 
2150 static int selinux_quota_on(struct dentry *dentry)
2151 {
2152 	const struct cred *cred = current_cred();
2153 
2154 	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2155 }
2156 
2157 static int selinux_syslog(int type)
2158 {
2159 	switch (type) {
2160 	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
2161 	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2162 		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2163 				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2164 	case SYSLOG_ACTION_CONSOLE_OFF:	/* Disable logging to console */
2165 	case SYSLOG_ACTION_CONSOLE_ON:	/* Enable logging to console */
2166 	/* Set level of messages printed to console */
2167 	case SYSLOG_ACTION_CONSOLE_LEVEL:
2168 		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2169 				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2170 				    NULL);
2171 	}
2172 	/* All other syslog types */
2173 	return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2174 			    SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2175 }
2176 
2177 /*
2178  * Check that a process has enough memory to allocate a new virtual
2179  * mapping. 0 means there is enough memory for the allocation to
2180  * succeed and -ENOMEM implies there is not.
2181  *
2182  * Do not audit the selinux permission check, as this is applied to all
2183  * processes that allocate mappings.
2184  */
2185 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2186 {
2187 	int rc, cap_sys_admin = 0;
2188 
2189 	rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2190 				 CAP_OPT_NOAUDIT, true);
2191 	if (rc == 0)
2192 		cap_sys_admin = 1;
2193 
2194 	return cap_sys_admin;
2195 }
2196 
2197 /* binprm security operations */
2198 
2199 static u32 ptrace_parent_sid(void)
2200 {
2201 	u32 sid = 0;
2202 	struct task_struct *tracer;
2203 
2204 	rcu_read_lock();
2205 	tracer = ptrace_parent(current);
2206 	if (tracer)
2207 		sid = task_sid_obj(tracer);
2208 	rcu_read_unlock();
2209 
2210 	return sid;
2211 }
2212 
2213 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2214 			    const struct task_security_struct *old_tsec,
2215 			    const struct task_security_struct *new_tsec)
2216 {
2217 	int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2218 	int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2219 	int rc;
2220 	u32 av;
2221 
2222 	if (!nnp && !nosuid)
2223 		return 0; /* neither NNP nor nosuid */
2224 
2225 	if (new_tsec->sid == old_tsec->sid)
2226 		return 0; /* No change in credentials */
2227 
2228 	/*
2229 	 * If the policy enables the nnp_nosuid_transition policy capability,
2230 	 * then we permit transitions under NNP or nosuid if the
2231 	 * policy allows the corresponding permission between
2232 	 * the old and new contexts.
2233 	 */
2234 	if (selinux_policycap_nnp_nosuid_transition()) {
2235 		av = 0;
2236 		if (nnp)
2237 			av |= PROCESS2__NNP_TRANSITION;
2238 		if (nosuid)
2239 			av |= PROCESS2__NOSUID_TRANSITION;
2240 		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2241 				  SECCLASS_PROCESS2, av, NULL);
2242 		if (!rc)
2243 			return 0;
2244 	}
2245 
2246 	/*
2247 	 * We also permit NNP or nosuid transitions to bounded SIDs,
2248 	 * i.e. SIDs that are guaranteed to only be allowed a subset
2249 	 * of the permissions of the current SID.
2250 	 */
2251 	rc = security_bounded_transition(old_tsec->sid,
2252 					 new_tsec->sid);
2253 	if (!rc)
2254 		return 0;
2255 
2256 	/*
2257 	 * On failure, preserve the errno values for NNP vs nosuid.
2258 	 * NNP:  Operation not permitted for caller.
2259 	 * nosuid:  Permission denied to file.
2260 	 */
2261 	if (nnp)
2262 		return -EPERM;
2263 	return -EACCES;
2264 }
2265 
2266 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2267 {
2268 	const struct task_security_struct *old_tsec;
2269 	struct task_security_struct *new_tsec;
2270 	struct inode_security_struct *isec;
2271 	struct common_audit_data ad;
2272 	struct inode *inode = file_inode(bprm->file);
2273 	int rc;
2274 
2275 	/* SELinux context only depends on initial program or script and not
2276 	 * the script interpreter */
2277 
2278 	old_tsec = selinux_cred(current_cred());
2279 	new_tsec = selinux_cred(bprm->cred);
2280 	isec = inode_security(inode);
2281 
2282 	/* Default to the current task SID. */
2283 	new_tsec->sid = old_tsec->sid;
2284 	new_tsec->osid = old_tsec->sid;
2285 
2286 	/* Reset fs, key, and sock SIDs on execve. */
2287 	new_tsec->create_sid = 0;
2288 	new_tsec->keycreate_sid = 0;
2289 	new_tsec->sockcreate_sid = 0;
2290 
2291 	/*
2292 	 * Before policy is loaded, label any task outside kernel space
2293 	 * as SECINITSID_INIT, so that any userspace tasks surviving from
2294 	 * early boot end up with a label different from SECINITSID_KERNEL
2295 	 * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL).
2296 	 */
2297 	if (!selinux_initialized()) {
2298 		new_tsec->sid = SECINITSID_INIT;
2299 		/* also clear the exec_sid just in case */
2300 		new_tsec->exec_sid = 0;
2301 		return 0;
2302 	}
2303 
2304 	if (old_tsec->exec_sid) {
2305 		new_tsec->sid = old_tsec->exec_sid;
2306 		/* Reset exec SID on execve. */
2307 		new_tsec->exec_sid = 0;
2308 
2309 		/* Fail on NNP or nosuid if not an allowed transition. */
2310 		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2311 		if (rc)
2312 			return rc;
2313 	} else {
2314 		/* Check for a default transition on this program. */
2315 		rc = security_transition_sid(old_tsec->sid,
2316 					     isec->sid, SECCLASS_PROCESS, NULL,
2317 					     &new_tsec->sid);
2318 		if (rc)
2319 			return rc;
2320 
2321 		/*
2322 		 * Fallback to old SID on NNP or nosuid if not an allowed
2323 		 * transition.
2324 		 */
2325 		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2326 		if (rc)
2327 			new_tsec->sid = old_tsec->sid;
2328 	}
2329 
2330 	ad.type = LSM_AUDIT_DATA_FILE;
2331 	ad.u.file = bprm->file;
2332 
2333 	if (new_tsec->sid == old_tsec->sid) {
2334 		rc = avc_has_perm(old_tsec->sid, isec->sid,
2335 				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2336 		if (rc)
2337 			return rc;
2338 	} else {
2339 		/* Check permissions for the transition. */
2340 		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2341 				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2342 		if (rc)
2343 			return rc;
2344 
2345 		rc = avc_has_perm(new_tsec->sid, isec->sid,
2346 				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2347 		if (rc)
2348 			return rc;
2349 
2350 		/* Check for shared state */
2351 		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2352 			rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2353 					  SECCLASS_PROCESS, PROCESS__SHARE,
2354 					  NULL);
2355 			if (rc)
2356 				return -EPERM;
2357 		}
2358 
2359 		/* Make sure that anyone attempting to ptrace over a task that
2360 		 * changes its SID has the appropriate permit */
2361 		if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2362 			u32 ptsid = ptrace_parent_sid();
2363 			if (ptsid != 0) {
2364 				rc = avc_has_perm(ptsid, new_tsec->sid,
2365 						  SECCLASS_PROCESS,
2366 						  PROCESS__PTRACE, NULL);
2367 				if (rc)
2368 					return -EPERM;
2369 			}
2370 		}
2371 
2372 		/* Clear any possibly unsafe personality bits on exec: */
2373 		bprm->per_clear |= PER_CLEAR_ON_SETID;
2374 
2375 		/* Enable secure mode for SIDs transitions unless
2376 		   the noatsecure permission is granted between
2377 		   the two SIDs, i.e. ahp returns 0. */
2378 		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2379 				  SECCLASS_PROCESS, PROCESS__NOATSECURE,
2380 				  NULL);
2381 		bprm->secureexec |= !!rc;
2382 	}
2383 
2384 	return 0;
2385 }
2386 
2387 static int match_file(const void *p, struct file *file, unsigned fd)
2388 {
2389 	return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2390 }
2391 
2392 /* Derived from fs/exec.c:flush_old_files. */
2393 static inline void flush_unauthorized_files(const struct cred *cred,
2394 					    struct files_struct *files)
2395 {
2396 	struct file *file, *devnull = NULL;
2397 	struct tty_struct *tty;
2398 	int drop_tty = 0;
2399 	unsigned n;
2400 
2401 	tty = get_current_tty();
2402 	if (tty) {
2403 		spin_lock(&tty->files_lock);
2404 		if (!list_empty(&tty->tty_files)) {
2405 			struct tty_file_private *file_priv;
2406 
2407 			/* Revalidate access to controlling tty.
2408 			   Use file_path_has_perm on the tty path directly
2409 			   rather than using file_has_perm, as this particular
2410 			   open file may belong to another process and we are
2411 			   only interested in the inode-based check here. */
2412 			file_priv = list_first_entry(&tty->tty_files,
2413 						struct tty_file_private, list);
2414 			file = file_priv->file;
2415 			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2416 				drop_tty = 1;
2417 		}
2418 		spin_unlock(&tty->files_lock);
2419 		tty_kref_put(tty);
2420 	}
2421 	/* Reset controlling tty. */
2422 	if (drop_tty)
2423 		no_tty();
2424 
2425 	/* Revalidate access to inherited open files. */
2426 	n = iterate_fd(files, 0, match_file, cred);
2427 	if (!n) /* none found? */
2428 		return;
2429 
2430 	devnull = dentry_open(&selinux_null, O_RDWR, cred);
2431 	if (IS_ERR(devnull))
2432 		devnull = NULL;
2433 	/* replace all the matching ones with this */
2434 	do {
2435 		replace_fd(n - 1, devnull, 0);
2436 	} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2437 	if (devnull)
2438 		fput(devnull);
2439 }
2440 
2441 /*
2442  * Prepare a process for imminent new credential changes due to exec
2443  */
2444 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2445 {
2446 	struct task_security_struct *new_tsec;
2447 	struct rlimit *rlim, *initrlim;
2448 	int rc, i;
2449 
2450 	new_tsec = selinux_cred(bprm->cred);
2451 	if (new_tsec->sid == new_tsec->osid)
2452 		return;
2453 
2454 	/* Close files for which the new task SID is not authorized. */
2455 	flush_unauthorized_files(bprm->cred, current->files);
2456 
2457 	/* Always clear parent death signal on SID transitions. */
2458 	current->pdeath_signal = 0;
2459 
2460 	/* Check whether the new SID can inherit resource limits from the old
2461 	 * SID.  If not, reset all soft limits to the lower of the current
2462 	 * task's hard limit and the init task's soft limit.
2463 	 *
2464 	 * Note that the setting of hard limits (even to lower them) can be
2465 	 * controlled by the setrlimit check.  The inclusion of the init task's
2466 	 * soft limit into the computation is to avoid resetting soft limits
2467 	 * higher than the default soft limit for cases where the default is
2468 	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2469 	 */
2470 	rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2471 			  PROCESS__RLIMITINH, NULL);
2472 	if (rc) {
2473 		/* protect against do_prlimit() */
2474 		task_lock(current);
2475 		for (i = 0; i < RLIM_NLIMITS; i++) {
2476 			rlim = current->signal->rlim + i;
2477 			initrlim = init_task.signal->rlim + i;
2478 			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2479 		}
2480 		task_unlock(current);
2481 		if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2482 			update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2483 	}
2484 }
2485 
2486 /*
2487  * Clean up the process immediately after the installation of new credentials
2488  * due to exec
2489  */
2490 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2491 {
2492 	const struct task_security_struct *tsec = selinux_cred(current_cred());
2493 	u32 osid, sid;
2494 	int rc;
2495 
2496 	osid = tsec->osid;
2497 	sid = tsec->sid;
2498 
2499 	if (sid == osid)
2500 		return;
2501 
2502 	/* Check whether the new SID can inherit signal state from the old SID.
2503 	 * If not, clear itimers to avoid subsequent signal generation and
2504 	 * flush and unblock signals.
2505 	 *
2506 	 * This must occur _after_ the task SID has been updated so that any
2507 	 * kill done after the flush will be checked against the new SID.
2508 	 */
2509 	rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2510 	if (rc) {
2511 		clear_itimer();
2512 
2513 		spin_lock_irq(&unrcu_pointer(current->sighand)->siglock);
2514 		if (!fatal_signal_pending(current)) {
2515 			flush_sigqueue(&current->pending);
2516 			flush_sigqueue(&current->signal->shared_pending);
2517 			flush_signal_handlers(current, 1);
2518 			sigemptyset(&current->blocked);
2519 			recalc_sigpending();
2520 		}
2521 		spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock);
2522 	}
2523 
2524 	/* Wake up the parent if it is waiting so that it can recheck
2525 	 * wait permission to the new task SID. */
2526 	read_lock(&tasklist_lock);
2527 	__wake_up_parent(current, unrcu_pointer(current->real_parent));
2528 	read_unlock(&tasklist_lock);
2529 }
2530 
2531 /* superblock security operations */
2532 
2533 static int selinux_sb_alloc_security(struct super_block *sb)
2534 {
2535 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
2536 
2537 	mutex_init(&sbsec->lock);
2538 	INIT_LIST_HEAD(&sbsec->isec_head);
2539 	spin_lock_init(&sbsec->isec_lock);
2540 	sbsec->sid = SECINITSID_UNLABELED;
2541 	sbsec->def_sid = SECINITSID_FILE;
2542 	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2543 
2544 	return 0;
2545 }
2546 
2547 static inline int opt_len(const char *s)
2548 {
2549 	bool open_quote = false;
2550 	int len;
2551 	char c;
2552 
2553 	for (len = 0; (c = s[len]) != '\0'; len++) {
2554 		if (c == '"')
2555 			open_quote = !open_quote;
2556 		if (c == ',' && !open_quote)
2557 			break;
2558 	}
2559 	return len;
2560 }
2561 
2562 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2563 {
2564 	char *from = options;
2565 	char *to = options;
2566 	bool first = true;
2567 	int rc;
2568 
2569 	while (1) {
2570 		int len = opt_len(from);
2571 		int token;
2572 		char *arg = NULL;
2573 
2574 		token = match_opt_prefix(from, len, &arg);
2575 
2576 		if (token != Opt_error) {
2577 			char *p, *q;
2578 
2579 			/* strip quotes */
2580 			if (arg) {
2581 				for (p = q = arg; p < from + len; p++) {
2582 					char c = *p;
2583 					if (c != '"')
2584 						*q++ = c;
2585 				}
2586 				arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2587 				if (!arg) {
2588 					rc = -ENOMEM;
2589 					goto free_opt;
2590 				}
2591 			}
2592 			rc = selinux_add_opt(token, arg, mnt_opts);
2593 			kfree(arg);
2594 			arg = NULL;
2595 			if (unlikely(rc)) {
2596 				goto free_opt;
2597 			}
2598 		} else {
2599 			if (!first) {	// copy with preceding comma
2600 				from--;
2601 				len++;
2602 			}
2603 			if (to != from)
2604 				memmove(to, from, len);
2605 			to += len;
2606 			first = false;
2607 		}
2608 		if (!from[len])
2609 			break;
2610 		from += len + 1;
2611 	}
2612 	*to = '\0';
2613 	return 0;
2614 
2615 free_opt:
2616 	if (*mnt_opts) {
2617 		selinux_free_mnt_opts(*mnt_opts);
2618 		*mnt_opts = NULL;
2619 	}
2620 	return rc;
2621 }
2622 
2623 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
2624 {
2625 	struct selinux_mnt_opts *opts = mnt_opts;
2626 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
2627 
2628 	/*
2629 	 * Superblock not initialized (i.e. no options) - reject if any
2630 	 * options specified, otherwise accept.
2631 	 */
2632 	if (!(sbsec->flags & SE_SBINITIALIZED))
2633 		return opts ? 1 : 0;
2634 
2635 	/*
2636 	 * Superblock initialized and no options specified - reject if
2637 	 * superblock has any options set, otherwise accept.
2638 	 */
2639 	if (!opts)
2640 		return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2641 
2642 	if (opts->fscontext_sid) {
2643 		if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2644 			       opts->fscontext_sid))
2645 			return 1;
2646 	}
2647 	if (opts->context_sid) {
2648 		if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2649 			       opts->context_sid))
2650 			return 1;
2651 	}
2652 	if (opts->rootcontext_sid) {
2653 		struct inode_security_struct *root_isec;
2654 
2655 		root_isec = backing_inode_security(sb->s_root);
2656 		if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2657 			       opts->rootcontext_sid))
2658 			return 1;
2659 	}
2660 	if (opts->defcontext_sid) {
2661 		if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2662 			       opts->defcontext_sid))
2663 			return 1;
2664 	}
2665 	return 0;
2666 }
2667 
2668 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2669 {
2670 	struct selinux_mnt_opts *opts = mnt_opts;
2671 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
2672 
2673 	if (!(sbsec->flags & SE_SBINITIALIZED))
2674 		return 0;
2675 
2676 	if (!opts)
2677 		return 0;
2678 
2679 	if (opts->fscontext_sid) {
2680 		if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2681 			       opts->fscontext_sid))
2682 			goto out_bad_option;
2683 	}
2684 	if (opts->context_sid) {
2685 		if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2686 			       opts->context_sid))
2687 			goto out_bad_option;
2688 	}
2689 	if (opts->rootcontext_sid) {
2690 		struct inode_security_struct *root_isec;
2691 		root_isec = backing_inode_security(sb->s_root);
2692 		if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2693 			       opts->rootcontext_sid))
2694 			goto out_bad_option;
2695 	}
2696 	if (opts->defcontext_sid) {
2697 		if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2698 			       opts->defcontext_sid))
2699 			goto out_bad_option;
2700 	}
2701 	return 0;
2702 
2703 out_bad_option:
2704 	pr_warn("SELinux: unable to change security options "
2705 	       "during remount (dev %s, type=%s)\n", sb->s_id,
2706 	       sb->s_type->name);
2707 	return -EINVAL;
2708 }
2709 
2710 static int selinux_sb_kern_mount(struct super_block *sb)
2711 {
2712 	const struct cred *cred = current_cred();
2713 	struct common_audit_data ad;
2714 
2715 	ad.type = LSM_AUDIT_DATA_DENTRY;
2716 	ad.u.dentry = sb->s_root;
2717 	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2718 }
2719 
2720 static int selinux_sb_statfs(struct dentry *dentry)
2721 {
2722 	const struct cred *cred = current_cred();
2723 	struct common_audit_data ad;
2724 
2725 	ad.type = LSM_AUDIT_DATA_DENTRY;
2726 	ad.u.dentry = dentry->d_sb->s_root;
2727 	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2728 }
2729 
2730 static int selinux_mount(const char *dev_name,
2731 			 const struct path *path,
2732 			 const char *type,
2733 			 unsigned long flags,
2734 			 void *data)
2735 {
2736 	const struct cred *cred = current_cred();
2737 
2738 	if (flags & MS_REMOUNT)
2739 		return superblock_has_perm(cred, path->dentry->d_sb,
2740 					   FILESYSTEM__REMOUNT, NULL);
2741 	else
2742 		return path_has_perm(cred, path, FILE__MOUNTON);
2743 }
2744 
2745 static int selinux_move_mount(const struct path *from_path,
2746 			      const struct path *to_path)
2747 {
2748 	const struct cred *cred = current_cred();
2749 
2750 	return path_has_perm(cred, to_path, FILE__MOUNTON);
2751 }
2752 
2753 static int selinux_umount(struct vfsmount *mnt, int flags)
2754 {
2755 	const struct cred *cred = current_cred();
2756 
2757 	return superblock_has_perm(cred, mnt->mnt_sb,
2758 				   FILESYSTEM__UNMOUNT, NULL);
2759 }
2760 
2761 static int selinux_fs_context_dup(struct fs_context *fc,
2762 				  struct fs_context *src_fc)
2763 {
2764 	const struct selinux_mnt_opts *src = src_fc->security;
2765 
2766 	if (!src)
2767 		return 0;
2768 
2769 	fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL);
2770 	return fc->security ? 0 : -ENOMEM;
2771 }
2772 
2773 static const struct fs_parameter_spec selinux_fs_parameters[] = {
2774 	fsparam_string(CONTEXT_STR,	Opt_context),
2775 	fsparam_string(DEFCONTEXT_STR,	Opt_defcontext),
2776 	fsparam_string(FSCONTEXT_STR,	Opt_fscontext),
2777 	fsparam_string(ROOTCONTEXT_STR,	Opt_rootcontext),
2778 	fsparam_flag  (SECLABEL_STR,	Opt_seclabel),
2779 	{}
2780 };
2781 
2782 static int selinux_fs_context_parse_param(struct fs_context *fc,
2783 					  struct fs_parameter *param)
2784 {
2785 	struct fs_parse_result result;
2786 	int opt;
2787 
2788 	opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2789 	if (opt < 0)
2790 		return opt;
2791 
2792 	return selinux_add_opt(opt, param->string, &fc->security);
2793 }
2794 
2795 /* inode security operations */
2796 
2797 static int selinux_inode_alloc_security(struct inode *inode)
2798 {
2799 	struct inode_security_struct *isec = selinux_inode(inode);
2800 	u32 sid = current_sid();
2801 
2802 	spin_lock_init(&isec->lock);
2803 	INIT_LIST_HEAD(&isec->list);
2804 	isec->inode = inode;
2805 	isec->sid = SECINITSID_UNLABELED;
2806 	isec->sclass = SECCLASS_FILE;
2807 	isec->task_sid = sid;
2808 	isec->initialized = LABEL_INVALID;
2809 
2810 	return 0;
2811 }
2812 
2813 static void selinux_inode_free_security(struct inode *inode)
2814 {
2815 	inode_free_security(inode);
2816 }
2817 
2818 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2819 					const struct qstr *name,
2820 					const char **xattr_name, void **ctx,
2821 					u32 *ctxlen)
2822 {
2823 	u32 newsid;
2824 	int rc;
2825 
2826 	rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2827 					   d_inode(dentry->d_parent), name,
2828 					   inode_mode_to_security_class(mode),
2829 					   &newsid);
2830 	if (rc)
2831 		return rc;
2832 
2833 	if (xattr_name)
2834 		*xattr_name = XATTR_NAME_SELINUX;
2835 
2836 	return security_sid_to_context(newsid, (char **)ctx,
2837 				       ctxlen);
2838 }
2839 
2840 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2841 					  struct qstr *name,
2842 					  const struct cred *old,
2843 					  struct cred *new)
2844 {
2845 	u32 newsid;
2846 	int rc;
2847 	struct task_security_struct *tsec;
2848 
2849 	rc = selinux_determine_inode_label(selinux_cred(old),
2850 					   d_inode(dentry->d_parent), name,
2851 					   inode_mode_to_security_class(mode),
2852 					   &newsid);
2853 	if (rc)
2854 		return rc;
2855 
2856 	tsec = selinux_cred(new);
2857 	tsec->create_sid = newsid;
2858 	return 0;
2859 }
2860 
2861 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2862 				       const struct qstr *qstr,
2863 				       const char **name,
2864 				       void **value, size_t *len)
2865 {
2866 	const struct task_security_struct *tsec = selinux_cred(current_cred());
2867 	struct superblock_security_struct *sbsec;
2868 	u32 newsid, clen;
2869 	int rc;
2870 	char *context;
2871 
2872 	sbsec = selinux_superblock(dir->i_sb);
2873 
2874 	newsid = tsec->create_sid;
2875 
2876 	rc = selinux_determine_inode_label(tsec, dir, qstr,
2877 		inode_mode_to_security_class(inode->i_mode),
2878 		&newsid);
2879 	if (rc)
2880 		return rc;
2881 
2882 	/* Possibly defer initialization to selinux_complete_init. */
2883 	if (sbsec->flags & SE_SBINITIALIZED) {
2884 		struct inode_security_struct *isec = selinux_inode(inode);
2885 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
2886 		isec->sid = newsid;
2887 		isec->initialized = LABEL_INITIALIZED;
2888 	}
2889 
2890 	if (!selinux_initialized() ||
2891 	    !(sbsec->flags & SBLABEL_MNT))
2892 		return -EOPNOTSUPP;
2893 
2894 	if (name)
2895 		*name = XATTR_SELINUX_SUFFIX;
2896 
2897 	if (value && len) {
2898 		rc = security_sid_to_context_force(newsid,
2899 						   &context, &clen);
2900 		if (rc)
2901 			return rc;
2902 		*value = context;
2903 		*len = clen;
2904 	}
2905 
2906 	return 0;
2907 }
2908 
2909 static int selinux_inode_init_security_anon(struct inode *inode,
2910 					    const struct qstr *name,
2911 					    const struct inode *context_inode)
2912 {
2913 	const struct task_security_struct *tsec = selinux_cred(current_cred());
2914 	struct common_audit_data ad;
2915 	struct inode_security_struct *isec;
2916 	int rc;
2917 
2918 	if (unlikely(!selinux_initialized()))
2919 		return 0;
2920 
2921 	isec = selinux_inode(inode);
2922 
2923 	/*
2924 	 * We only get here once per ephemeral inode.  The inode has
2925 	 * been initialized via inode_alloc_security but is otherwise
2926 	 * untouched.
2927 	 */
2928 
2929 	if (context_inode) {
2930 		struct inode_security_struct *context_isec =
2931 			selinux_inode(context_inode);
2932 		if (context_isec->initialized != LABEL_INITIALIZED) {
2933 			pr_err("SELinux:  context_inode is not initialized");
2934 			return -EACCES;
2935 		}
2936 
2937 		isec->sclass = context_isec->sclass;
2938 		isec->sid = context_isec->sid;
2939 	} else {
2940 		isec->sclass = SECCLASS_ANON_INODE;
2941 		rc = security_transition_sid(
2942 			tsec->sid, tsec->sid,
2943 			isec->sclass, name, &isec->sid);
2944 		if (rc)
2945 			return rc;
2946 	}
2947 
2948 	isec->initialized = LABEL_INITIALIZED;
2949 	/*
2950 	 * Now that we've initialized security, check whether we're
2951 	 * allowed to actually create this type of anonymous inode.
2952 	 */
2953 
2954 	ad.type = LSM_AUDIT_DATA_ANONINODE;
2955 	ad.u.anonclass = name ? (const char *)name->name : "?";
2956 
2957 	return avc_has_perm(tsec->sid,
2958 			    isec->sid,
2959 			    isec->sclass,
2960 			    FILE__CREATE,
2961 			    &ad);
2962 }
2963 
2964 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2965 {
2966 	return may_create(dir, dentry, SECCLASS_FILE);
2967 }
2968 
2969 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2970 {
2971 	return may_link(dir, old_dentry, MAY_LINK);
2972 }
2973 
2974 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2975 {
2976 	return may_link(dir, dentry, MAY_UNLINK);
2977 }
2978 
2979 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2980 {
2981 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
2982 }
2983 
2984 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2985 {
2986 	return may_create(dir, dentry, SECCLASS_DIR);
2987 }
2988 
2989 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2990 {
2991 	return may_link(dir, dentry, MAY_RMDIR);
2992 }
2993 
2994 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2995 {
2996 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
2997 }
2998 
2999 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3000 				struct inode *new_inode, struct dentry *new_dentry)
3001 {
3002 	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3003 }
3004 
3005 static int selinux_inode_readlink(struct dentry *dentry)
3006 {
3007 	const struct cred *cred = current_cred();
3008 
3009 	return dentry_has_perm(cred, dentry, FILE__READ);
3010 }
3011 
3012 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3013 				     bool rcu)
3014 {
3015 	const struct cred *cred = current_cred();
3016 	struct common_audit_data ad;
3017 	struct inode_security_struct *isec;
3018 	u32 sid;
3019 
3020 	validate_creds(cred);
3021 
3022 	ad.type = LSM_AUDIT_DATA_DENTRY;
3023 	ad.u.dentry = dentry;
3024 	sid = cred_sid(cred);
3025 	isec = inode_security_rcu(inode, rcu);
3026 	if (IS_ERR(isec))
3027 		return PTR_ERR(isec);
3028 
3029 	return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad);
3030 }
3031 
3032 static noinline int audit_inode_permission(struct inode *inode,
3033 					   u32 perms, u32 audited, u32 denied,
3034 					   int result)
3035 {
3036 	struct common_audit_data ad;
3037 	struct inode_security_struct *isec = selinux_inode(inode);
3038 
3039 	ad.type = LSM_AUDIT_DATA_INODE;
3040 	ad.u.inode = inode;
3041 
3042 	return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3043 			    audited, denied, result, &ad);
3044 }
3045 
3046 static int selinux_inode_permission(struct inode *inode, int mask)
3047 {
3048 	const struct cred *cred = current_cred();
3049 	u32 perms;
3050 	bool from_access;
3051 	bool no_block = mask & MAY_NOT_BLOCK;
3052 	struct inode_security_struct *isec;
3053 	u32 sid;
3054 	struct av_decision avd;
3055 	int rc, rc2;
3056 	u32 audited, denied;
3057 
3058 	from_access = mask & MAY_ACCESS;
3059 	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3060 
3061 	/* No permission to check.  Existence test. */
3062 	if (!mask)
3063 		return 0;
3064 
3065 	validate_creds(cred);
3066 
3067 	if (unlikely(IS_PRIVATE(inode)))
3068 		return 0;
3069 
3070 	perms = file_mask_to_av(inode->i_mode, mask);
3071 
3072 	sid = cred_sid(cred);
3073 	isec = inode_security_rcu(inode, no_block);
3074 	if (IS_ERR(isec))
3075 		return PTR_ERR(isec);
3076 
3077 	rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0,
3078 				  &avd);
3079 	audited = avc_audit_required(perms, &avd, rc,
3080 				     from_access ? FILE__AUDIT_ACCESS : 0,
3081 				     &denied);
3082 	if (likely(!audited))
3083 		return rc;
3084 
3085 	rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3086 	if (rc2)
3087 		return rc2;
3088 	return rc;
3089 }
3090 
3091 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3092 {
3093 	const struct cred *cred = current_cred();
3094 	struct inode *inode = d_backing_inode(dentry);
3095 	unsigned int ia_valid = iattr->ia_valid;
3096 	__u32 av = FILE__WRITE;
3097 
3098 	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3099 	if (ia_valid & ATTR_FORCE) {
3100 		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3101 			      ATTR_FORCE);
3102 		if (!ia_valid)
3103 			return 0;
3104 	}
3105 
3106 	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3107 			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3108 		return dentry_has_perm(cred, dentry, FILE__SETATTR);
3109 
3110 	if (selinux_policycap_openperm() &&
3111 	    inode->i_sb->s_magic != SOCKFS_MAGIC &&
3112 	    (ia_valid & ATTR_SIZE) &&
3113 	    !(ia_valid & ATTR_FILE))
3114 		av |= FILE__OPEN;
3115 
3116 	return dentry_has_perm(cred, dentry, av);
3117 }
3118 
3119 static int selinux_inode_getattr(const struct path *path)
3120 {
3121 	return path_has_perm(current_cred(), path, FILE__GETATTR);
3122 }
3123 
3124 static bool has_cap_mac_admin(bool audit)
3125 {
3126 	const struct cred *cred = current_cred();
3127 	unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3128 
3129 	if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3130 		return false;
3131 	if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3132 		return false;
3133 	return true;
3134 }
3135 
3136 static int selinux_inode_setxattr(struct mnt_idmap *idmap,
3137 				  struct dentry *dentry, const char *name,
3138 				  const void *value, size_t size, int flags)
3139 {
3140 	struct inode *inode = d_backing_inode(dentry);
3141 	struct inode_security_struct *isec;
3142 	struct superblock_security_struct *sbsec;
3143 	struct common_audit_data ad;
3144 	u32 newsid, sid = current_sid();
3145 	int rc = 0;
3146 
3147 	if (strcmp(name, XATTR_NAME_SELINUX)) {
3148 		rc = cap_inode_setxattr(dentry, name, value, size, flags);
3149 		if (rc)
3150 			return rc;
3151 
3152 		/* Not an attribute we recognize, so just check the
3153 		   ordinary setattr permission. */
3154 		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3155 	}
3156 
3157 	if (!selinux_initialized())
3158 		return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM);
3159 
3160 	sbsec = selinux_superblock(inode->i_sb);
3161 	if (!(sbsec->flags & SBLABEL_MNT))
3162 		return -EOPNOTSUPP;
3163 
3164 	if (!inode_owner_or_capable(idmap, inode))
3165 		return -EPERM;
3166 
3167 	ad.type = LSM_AUDIT_DATA_DENTRY;
3168 	ad.u.dentry = dentry;
3169 
3170 	isec = backing_inode_security(dentry);
3171 	rc = avc_has_perm(sid, isec->sid, isec->sclass,
3172 			  FILE__RELABELFROM, &ad);
3173 	if (rc)
3174 		return rc;
3175 
3176 	rc = security_context_to_sid(value, size, &newsid,
3177 				     GFP_KERNEL);
3178 	if (rc == -EINVAL) {
3179 		if (!has_cap_mac_admin(true)) {
3180 			struct audit_buffer *ab;
3181 			size_t audit_size;
3182 
3183 			/* We strip a nul only if it is at the end, otherwise the
3184 			 * context contains a nul and we should audit that */
3185 			if (value) {
3186 				const char *str = value;
3187 
3188 				if (str[size - 1] == '\0')
3189 					audit_size = size - 1;
3190 				else
3191 					audit_size = size;
3192 			} else {
3193 				audit_size = 0;
3194 			}
3195 			ab = audit_log_start(audit_context(),
3196 					     GFP_ATOMIC, AUDIT_SELINUX_ERR);
3197 			if (!ab)
3198 				return rc;
3199 			audit_log_format(ab, "op=setxattr invalid_context=");
3200 			audit_log_n_untrustedstring(ab, value, audit_size);
3201 			audit_log_end(ab);
3202 
3203 			return rc;
3204 		}
3205 		rc = security_context_to_sid_force(value,
3206 						   size, &newsid);
3207 	}
3208 	if (rc)
3209 		return rc;
3210 
3211 	rc = avc_has_perm(sid, newsid, isec->sclass,
3212 			  FILE__RELABELTO, &ad);
3213 	if (rc)
3214 		return rc;
3215 
3216 	rc = security_validate_transition(isec->sid, newsid,
3217 					  sid, isec->sclass);
3218 	if (rc)
3219 		return rc;
3220 
3221 	return avc_has_perm(newsid,
3222 			    sbsec->sid,
3223 			    SECCLASS_FILESYSTEM,
3224 			    FILESYSTEM__ASSOCIATE,
3225 			    &ad);
3226 }
3227 
3228 static int selinux_inode_set_acl(struct mnt_idmap *idmap,
3229 				 struct dentry *dentry, const char *acl_name,
3230 				 struct posix_acl *kacl)
3231 {
3232 	return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3233 }
3234 
3235 static int selinux_inode_get_acl(struct mnt_idmap *idmap,
3236 				 struct dentry *dentry, const char *acl_name)
3237 {
3238 	return dentry_has_perm(current_cred(), dentry, FILE__GETATTR);
3239 }
3240 
3241 static int selinux_inode_remove_acl(struct mnt_idmap *idmap,
3242 				    struct dentry *dentry, const char *acl_name)
3243 {
3244 	return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3245 }
3246 
3247 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3248 					const void *value, size_t size,
3249 					int flags)
3250 {
3251 	struct inode *inode = d_backing_inode(dentry);
3252 	struct inode_security_struct *isec;
3253 	u32 newsid;
3254 	int rc;
3255 
3256 	if (strcmp(name, XATTR_NAME_SELINUX)) {
3257 		/* Not an attribute we recognize, so nothing to do. */
3258 		return;
3259 	}
3260 
3261 	if (!selinux_initialized()) {
3262 		/* If we haven't even been initialized, then we can't validate
3263 		 * against a policy, so leave the label as invalid. It may
3264 		 * resolve to a valid label on the next revalidation try if
3265 		 * we've since initialized.
3266 		 */
3267 		return;
3268 	}
3269 
3270 	rc = security_context_to_sid_force(value, size,
3271 					   &newsid);
3272 	if (rc) {
3273 		pr_err("SELinux:  unable to map context to SID"
3274 		       "for (%s, %lu), rc=%d\n",
3275 		       inode->i_sb->s_id, inode->i_ino, -rc);
3276 		return;
3277 	}
3278 
3279 	isec = backing_inode_security(dentry);
3280 	spin_lock(&isec->lock);
3281 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3282 	isec->sid = newsid;
3283 	isec->initialized = LABEL_INITIALIZED;
3284 	spin_unlock(&isec->lock);
3285 }
3286 
3287 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3288 {
3289 	const struct cred *cred = current_cred();
3290 
3291 	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3292 }
3293 
3294 static int selinux_inode_listxattr(struct dentry *dentry)
3295 {
3296 	const struct cred *cred = current_cred();
3297 
3298 	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3299 }
3300 
3301 static int selinux_inode_removexattr(struct mnt_idmap *idmap,
3302 				     struct dentry *dentry, const char *name)
3303 {
3304 	if (strcmp(name, XATTR_NAME_SELINUX)) {
3305 		int rc = cap_inode_removexattr(idmap, dentry, name);
3306 		if (rc)
3307 			return rc;
3308 
3309 		/* Not an attribute we recognize, so just check the
3310 		   ordinary setattr permission. */
3311 		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3312 	}
3313 
3314 	if (!selinux_initialized())
3315 		return 0;
3316 
3317 	/* No one is allowed to remove a SELinux security label.
3318 	   You can change the label, but all data must be labeled. */
3319 	return -EACCES;
3320 }
3321 
3322 static int selinux_path_notify(const struct path *path, u64 mask,
3323 						unsigned int obj_type)
3324 {
3325 	int ret;
3326 	u32 perm;
3327 
3328 	struct common_audit_data ad;
3329 
3330 	ad.type = LSM_AUDIT_DATA_PATH;
3331 	ad.u.path = *path;
3332 
3333 	/*
3334 	 * Set permission needed based on the type of mark being set.
3335 	 * Performs an additional check for sb watches.
3336 	 */
3337 	switch (obj_type) {
3338 	case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3339 		perm = FILE__WATCH_MOUNT;
3340 		break;
3341 	case FSNOTIFY_OBJ_TYPE_SB:
3342 		perm = FILE__WATCH_SB;
3343 		ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3344 						FILESYSTEM__WATCH, &ad);
3345 		if (ret)
3346 			return ret;
3347 		break;
3348 	case FSNOTIFY_OBJ_TYPE_INODE:
3349 		perm = FILE__WATCH;
3350 		break;
3351 	default:
3352 		return -EINVAL;
3353 	}
3354 
3355 	/* blocking watches require the file:watch_with_perm permission */
3356 	if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3357 		perm |= FILE__WATCH_WITH_PERM;
3358 
3359 	/* watches on read-like events need the file:watch_reads permission */
3360 	if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3361 		perm |= FILE__WATCH_READS;
3362 
3363 	return path_has_perm(current_cred(), path, perm);
3364 }
3365 
3366 /*
3367  * Copy the inode security context value to the user.
3368  *
3369  * Permission check is handled by selinux_inode_getxattr hook.
3370  */
3371 static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3372 				     struct inode *inode, const char *name,
3373 				     void **buffer, bool alloc)
3374 {
3375 	u32 size;
3376 	int error;
3377 	char *context = NULL;
3378 	struct inode_security_struct *isec;
3379 
3380 	/*
3381 	 * If we're not initialized yet, then we can't validate contexts, so
3382 	 * just let vfs_getxattr fall back to using the on-disk xattr.
3383 	 */
3384 	if (!selinux_initialized() ||
3385 	    strcmp(name, XATTR_SELINUX_SUFFIX))
3386 		return -EOPNOTSUPP;
3387 
3388 	/*
3389 	 * If the caller has CAP_MAC_ADMIN, then get the raw context
3390 	 * value even if it is not defined by current policy; otherwise,
3391 	 * use the in-core value under current policy.
3392 	 * Use the non-auditing forms of the permission checks since
3393 	 * getxattr may be called by unprivileged processes commonly
3394 	 * and lack of permission just means that we fall back to the
3395 	 * in-core context value, not a denial.
3396 	 */
3397 	isec = inode_security(inode);
3398 	if (has_cap_mac_admin(false))
3399 		error = security_sid_to_context_force(isec->sid, &context,
3400 						      &size);
3401 	else
3402 		error = security_sid_to_context(isec->sid,
3403 						&context, &size);
3404 	if (error)
3405 		return error;
3406 	error = size;
3407 	if (alloc) {
3408 		*buffer = context;
3409 		goto out_nofree;
3410 	}
3411 	kfree(context);
3412 out_nofree:
3413 	return error;
3414 }
3415 
3416 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3417 				     const void *value, size_t size, int flags)
3418 {
3419 	struct inode_security_struct *isec = inode_security_novalidate(inode);
3420 	struct superblock_security_struct *sbsec;
3421 	u32 newsid;
3422 	int rc;
3423 
3424 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
3425 		return -EOPNOTSUPP;
3426 
3427 	sbsec = selinux_superblock(inode->i_sb);
3428 	if (!(sbsec->flags & SBLABEL_MNT))
3429 		return -EOPNOTSUPP;
3430 
3431 	if (!value || !size)
3432 		return -EACCES;
3433 
3434 	rc = security_context_to_sid(value, size, &newsid,
3435 				     GFP_KERNEL);
3436 	if (rc)
3437 		return rc;
3438 
3439 	spin_lock(&isec->lock);
3440 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3441 	isec->sid = newsid;
3442 	isec->initialized = LABEL_INITIALIZED;
3443 	spin_unlock(&isec->lock);
3444 	return 0;
3445 }
3446 
3447 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3448 {
3449 	const int len = sizeof(XATTR_NAME_SELINUX);
3450 
3451 	if (!selinux_initialized())
3452 		return 0;
3453 
3454 	if (buffer && len <= buffer_size)
3455 		memcpy(buffer, XATTR_NAME_SELINUX, len);
3456 	return len;
3457 }
3458 
3459 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3460 {
3461 	struct inode_security_struct *isec = inode_security_novalidate(inode);
3462 	*secid = isec->sid;
3463 }
3464 
3465 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3466 {
3467 	u32 sid;
3468 	struct task_security_struct *tsec;
3469 	struct cred *new_creds = *new;
3470 
3471 	if (new_creds == NULL) {
3472 		new_creds = prepare_creds();
3473 		if (!new_creds)
3474 			return -ENOMEM;
3475 	}
3476 
3477 	tsec = selinux_cred(new_creds);
3478 	/* Get label from overlay inode and set it in create_sid */
3479 	selinux_inode_getsecid(d_inode(src), &sid);
3480 	tsec->create_sid = sid;
3481 	*new = new_creds;
3482 	return 0;
3483 }
3484 
3485 static int selinux_inode_copy_up_xattr(const char *name)
3486 {
3487 	/* The copy_up hook above sets the initial context on an inode, but we
3488 	 * don't then want to overwrite it by blindly copying all the lower
3489 	 * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3490 	 */
3491 	if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3492 		return 1; /* Discard */
3493 	/*
3494 	 * Any other attribute apart from SELINUX is not claimed, supported
3495 	 * by selinux.
3496 	 */
3497 	return -EOPNOTSUPP;
3498 }
3499 
3500 /* kernfs node operations */
3501 
3502 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3503 					struct kernfs_node *kn)
3504 {
3505 	const struct task_security_struct *tsec = selinux_cred(current_cred());
3506 	u32 parent_sid, newsid, clen;
3507 	int rc;
3508 	char *context;
3509 
3510 	rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3511 	if (rc == -ENODATA)
3512 		return 0;
3513 	else if (rc < 0)
3514 		return rc;
3515 
3516 	clen = (u32)rc;
3517 	context = kmalloc(clen, GFP_KERNEL);
3518 	if (!context)
3519 		return -ENOMEM;
3520 
3521 	rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3522 	if (rc < 0) {
3523 		kfree(context);
3524 		return rc;
3525 	}
3526 
3527 	rc = security_context_to_sid(context, clen, &parent_sid,
3528 				     GFP_KERNEL);
3529 	kfree(context);
3530 	if (rc)
3531 		return rc;
3532 
3533 	if (tsec->create_sid) {
3534 		newsid = tsec->create_sid;
3535 	} else {
3536 		u16 secclass = inode_mode_to_security_class(kn->mode);
3537 		struct qstr q;
3538 
3539 		q.name = kn->name;
3540 		q.hash_len = hashlen_string(kn_dir, kn->name);
3541 
3542 		rc = security_transition_sid(tsec->sid,
3543 					     parent_sid, secclass, &q,
3544 					     &newsid);
3545 		if (rc)
3546 			return rc;
3547 	}
3548 
3549 	rc = security_sid_to_context_force(newsid,
3550 					   &context, &clen);
3551 	if (rc)
3552 		return rc;
3553 
3554 	rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3555 			      XATTR_CREATE);
3556 	kfree(context);
3557 	return rc;
3558 }
3559 
3560 
3561 /* file security operations */
3562 
3563 static int selinux_revalidate_file_permission(struct file *file, int mask)
3564 {
3565 	const struct cred *cred = current_cred();
3566 	struct inode *inode = file_inode(file);
3567 
3568 	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3569 	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3570 		mask |= MAY_APPEND;
3571 
3572 	return file_has_perm(cred, file,
3573 			     file_mask_to_av(inode->i_mode, mask));
3574 }
3575 
3576 static int selinux_file_permission(struct file *file, int mask)
3577 {
3578 	struct inode *inode = file_inode(file);
3579 	struct file_security_struct *fsec = selinux_file(file);
3580 	struct inode_security_struct *isec;
3581 	u32 sid = current_sid();
3582 
3583 	if (!mask)
3584 		/* No permission to check.  Existence test. */
3585 		return 0;
3586 
3587 	isec = inode_security(inode);
3588 	if (sid == fsec->sid && fsec->isid == isec->sid &&
3589 	    fsec->pseqno == avc_policy_seqno())
3590 		/* No change since file_open check. */
3591 		return 0;
3592 
3593 	return selinux_revalidate_file_permission(file, mask);
3594 }
3595 
3596 static int selinux_file_alloc_security(struct file *file)
3597 {
3598 	struct file_security_struct *fsec = selinux_file(file);
3599 	u32 sid = current_sid();
3600 
3601 	fsec->sid = sid;
3602 	fsec->fown_sid = sid;
3603 
3604 	return 0;
3605 }
3606 
3607 /*
3608  * Check whether a task has the ioctl permission and cmd
3609  * operation to an inode.
3610  */
3611 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3612 		u32 requested, u16 cmd)
3613 {
3614 	struct common_audit_data ad;
3615 	struct file_security_struct *fsec = selinux_file(file);
3616 	struct inode *inode = file_inode(file);
3617 	struct inode_security_struct *isec;
3618 	struct lsm_ioctlop_audit ioctl;
3619 	u32 ssid = cred_sid(cred);
3620 	int rc;
3621 	u8 driver = cmd >> 8;
3622 	u8 xperm = cmd & 0xff;
3623 
3624 	ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3625 	ad.u.op = &ioctl;
3626 	ad.u.op->cmd = cmd;
3627 	ad.u.op->path = file->f_path;
3628 
3629 	if (ssid != fsec->sid) {
3630 		rc = avc_has_perm(ssid, fsec->sid,
3631 				SECCLASS_FD,
3632 				FD__USE,
3633 				&ad);
3634 		if (rc)
3635 			goto out;
3636 	}
3637 
3638 	if (unlikely(IS_PRIVATE(inode)))
3639 		return 0;
3640 
3641 	isec = inode_security(inode);
3642 	rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
3643 				    requested, driver, xperm, &ad);
3644 out:
3645 	return rc;
3646 }
3647 
3648 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3649 			      unsigned long arg)
3650 {
3651 	const struct cred *cred = current_cred();
3652 	int error = 0;
3653 
3654 	switch (cmd) {
3655 	case FIONREAD:
3656 	case FIBMAP:
3657 	case FIGETBSZ:
3658 	case FS_IOC_GETFLAGS:
3659 	case FS_IOC_GETVERSION:
3660 		error = file_has_perm(cred, file, FILE__GETATTR);
3661 		break;
3662 
3663 	case FS_IOC_SETFLAGS:
3664 	case FS_IOC_SETVERSION:
3665 		error = file_has_perm(cred, file, FILE__SETATTR);
3666 		break;
3667 
3668 	/* sys_ioctl() checks */
3669 	case FIONBIO:
3670 	case FIOASYNC:
3671 		error = file_has_perm(cred, file, 0);
3672 		break;
3673 
3674 	case KDSKBENT:
3675 	case KDSKBSENT:
3676 		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3677 					    CAP_OPT_NONE, true);
3678 		break;
3679 
3680 	case FIOCLEX:
3681 	case FIONCLEX:
3682 		if (!selinux_policycap_ioctl_skip_cloexec())
3683 			error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3684 		break;
3685 
3686 	/* default case assumes that the command will go
3687 	 * to the file's ioctl() function.
3688 	 */
3689 	default:
3690 		error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3691 	}
3692 	return error;
3693 }
3694 
3695 static int default_noexec __ro_after_init;
3696 
3697 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3698 {
3699 	const struct cred *cred = current_cred();
3700 	u32 sid = cred_sid(cred);
3701 	int rc = 0;
3702 
3703 	if (default_noexec &&
3704 	    (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3705 				   (!shared && (prot & PROT_WRITE)))) {
3706 		/*
3707 		 * We are making executable an anonymous mapping or a
3708 		 * private file mapping that will also be writable.
3709 		 * This has an additional check.
3710 		 */
3711 		rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3712 				  PROCESS__EXECMEM, NULL);
3713 		if (rc)
3714 			goto error;
3715 	}
3716 
3717 	if (file) {
3718 		/* read access is always possible with a mapping */
3719 		u32 av = FILE__READ;
3720 
3721 		/* write access only matters if the mapping is shared */
3722 		if (shared && (prot & PROT_WRITE))
3723 			av |= FILE__WRITE;
3724 
3725 		if (prot & PROT_EXEC)
3726 			av |= FILE__EXECUTE;
3727 
3728 		return file_has_perm(cred, file, av);
3729 	}
3730 
3731 error:
3732 	return rc;
3733 }
3734 
3735 static int selinux_mmap_addr(unsigned long addr)
3736 {
3737 	int rc = 0;
3738 
3739 	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3740 		u32 sid = current_sid();
3741 		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3742 				  MEMPROTECT__MMAP_ZERO, NULL);
3743 	}
3744 
3745 	return rc;
3746 }
3747 
3748 static int selinux_mmap_file(struct file *file,
3749 			     unsigned long reqprot __always_unused,
3750 			     unsigned long prot, unsigned long flags)
3751 {
3752 	struct common_audit_data ad;
3753 	int rc;
3754 
3755 	if (file) {
3756 		ad.type = LSM_AUDIT_DATA_FILE;
3757 		ad.u.file = file;
3758 		rc = inode_has_perm(current_cred(), file_inode(file),
3759 				    FILE__MAP, &ad);
3760 		if (rc)
3761 			return rc;
3762 	}
3763 
3764 	return file_map_prot_check(file, prot,
3765 				   (flags & MAP_TYPE) == MAP_SHARED);
3766 }
3767 
3768 static int selinux_file_mprotect(struct vm_area_struct *vma,
3769 				 unsigned long reqprot __always_unused,
3770 				 unsigned long prot)
3771 {
3772 	const struct cred *cred = current_cred();
3773 	u32 sid = cred_sid(cred);
3774 
3775 	if (default_noexec &&
3776 	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3777 		int rc = 0;
3778 		if (vma->vm_start >= vma->vm_mm->start_brk &&
3779 		    vma->vm_end <= vma->vm_mm->brk) {
3780 			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3781 					  PROCESS__EXECHEAP, NULL);
3782 		} else if (!vma->vm_file &&
3783 			   ((vma->vm_start <= vma->vm_mm->start_stack &&
3784 			     vma->vm_end >= vma->vm_mm->start_stack) ||
3785 			    vma_is_stack_for_current(vma))) {
3786 			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3787 					  PROCESS__EXECSTACK, NULL);
3788 		} else if (vma->vm_file && vma->anon_vma) {
3789 			/*
3790 			 * We are making executable a file mapping that has
3791 			 * had some COW done. Since pages might have been
3792 			 * written, check ability to execute the possibly
3793 			 * modified content.  This typically should only
3794 			 * occur for text relocations.
3795 			 */
3796 			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3797 		}
3798 		if (rc)
3799 			return rc;
3800 	}
3801 
3802 	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3803 }
3804 
3805 static int selinux_file_lock(struct file *file, unsigned int cmd)
3806 {
3807 	const struct cred *cred = current_cred();
3808 
3809 	return file_has_perm(cred, file, FILE__LOCK);
3810 }
3811 
3812 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3813 			      unsigned long arg)
3814 {
3815 	const struct cred *cred = current_cred();
3816 	int err = 0;
3817 
3818 	switch (cmd) {
3819 	case F_SETFL:
3820 		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3821 			err = file_has_perm(cred, file, FILE__WRITE);
3822 			break;
3823 		}
3824 		fallthrough;
3825 	case F_SETOWN:
3826 	case F_SETSIG:
3827 	case F_GETFL:
3828 	case F_GETOWN:
3829 	case F_GETSIG:
3830 	case F_GETOWNER_UIDS:
3831 		/* Just check FD__USE permission */
3832 		err = file_has_perm(cred, file, 0);
3833 		break;
3834 	case F_GETLK:
3835 	case F_SETLK:
3836 	case F_SETLKW:
3837 	case F_OFD_GETLK:
3838 	case F_OFD_SETLK:
3839 	case F_OFD_SETLKW:
3840 #if BITS_PER_LONG == 32
3841 	case F_GETLK64:
3842 	case F_SETLK64:
3843 	case F_SETLKW64:
3844 #endif
3845 		err = file_has_perm(cred, file, FILE__LOCK);
3846 		break;
3847 	}
3848 
3849 	return err;
3850 }
3851 
3852 static void selinux_file_set_fowner(struct file *file)
3853 {
3854 	struct file_security_struct *fsec;
3855 
3856 	fsec = selinux_file(file);
3857 	fsec->fown_sid = current_sid();
3858 }
3859 
3860 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3861 				       struct fown_struct *fown, int signum)
3862 {
3863 	struct file *file;
3864 	u32 sid = task_sid_obj(tsk);
3865 	u32 perm;
3866 	struct file_security_struct *fsec;
3867 
3868 	/* struct fown_struct is never outside the context of a struct file */
3869 	file = container_of(fown, struct file, f_owner);
3870 
3871 	fsec = selinux_file(file);
3872 
3873 	if (!signum)
3874 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3875 	else
3876 		perm = signal_to_av(signum);
3877 
3878 	return avc_has_perm(fsec->fown_sid, sid,
3879 			    SECCLASS_PROCESS, perm, NULL);
3880 }
3881 
3882 static int selinux_file_receive(struct file *file)
3883 {
3884 	const struct cred *cred = current_cred();
3885 
3886 	return file_has_perm(cred, file, file_to_av(file));
3887 }
3888 
3889 static int selinux_file_open(struct file *file)
3890 {
3891 	struct file_security_struct *fsec;
3892 	struct inode_security_struct *isec;
3893 
3894 	fsec = selinux_file(file);
3895 	isec = inode_security(file_inode(file));
3896 	/*
3897 	 * Save inode label and policy sequence number
3898 	 * at open-time so that selinux_file_permission
3899 	 * can determine whether revalidation is necessary.
3900 	 * Task label is already saved in the file security
3901 	 * struct as its SID.
3902 	 */
3903 	fsec->isid = isec->sid;
3904 	fsec->pseqno = avc_policy_seqno();
3905 	/*
3906 	 * Since the inode label or policy seqno may have changed
3907 	 * between the selinux_inode_permission check and the saving
3908 	 * of state above, recheck that access is still permitted.
3909 	 * Otherwise, access might never be revalidated against the
3910 	 * new inode label or new policy.
3911 	 * This check is not redundant - do not remove.
3912 	 */
3913 	return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3914 }
3915 
3916 /* task security operations */
3917 
3918 static int selinux_task_alloc(struct task_struct *task,
3919 			      unsigned long clone_flags)
3920 {
3921 	u32 sid = current_sid();
3922 
3923 	return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3924 }
3925 
3926 /*
3927  * prepare a new set of credentials for modification
3928  */
3929 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3930 				gfp_t gfp)
3931 {
3932 	const struct task_security_struct *old_tsec = selinux_cred(old);
3933 	struct task_security_struct *tsec = selinux_cred(new);
3934 
3935 	*tsec = *old_tsec;
3936 	return 0;
3937 }
3938 
3939 /*
3940  * transfer the SELinux data to a blank set of creds
3941  */
3942 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3943 {
3944 	const struct task_security_struct *old_tsec = selinux_cred(old);
3945 	struct task_security_struct *tsec = selinux_cred(new);
3946 
3947 	*tsec = *old_tsec;
3948 }
3949 
3950 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3951 {
3952 	*secid = cred_sid(c);
3953 }
3954 
3955 /*
3956  * set the security data for a kernel service
3957  * - all the creation contexts are set to unlabelled
3958  */
3959 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3960 {
3961 	struct task_security_struct *tsec = selinux_cred(new);
3962 	u32 sid = current_sid();
3963 	int ret;
3964 
3965 	ret = avc_has_perm(sid, secid,
3966 			   SECCLASS_KERNEL_SERVICE,
3967 			   KERNEL_SERVICE__USE_AS_OVERRIDE,
3968 			   NULL);
3969 	if (ret == 0) {
3970 		tsec->sid = secid;
3971 		tsec->create_sid = 0;
3972 		tsec->keycreate_sid = 0;
3973 		tsec->sockcreate_sid = 0;
3974 	}
3975 	return ret;
3976 }
3977 
3978 /*
3979  * set the file creation context in a security record to the same as the
3980  * objective context of the specified inode
3981  */
3982 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3983 {
3984 	struct inode_security_struct *isec = inode_security(inode);
3985 	struct task_security_struct *tsec = selinux_cred(new);
3986 	u32 sid = current_sid();
3987 	int ret;
3988 
3989 	ret = avc_has_perm(sid, isec->sid,
3990 			   SECCLASS_KERNEL_SERVICE,
3991 			   KERNEL_SERVICE__CREATE_FILES_AS,
3992 			   NULL);
3993 
3994 	if (ret == 0)
3995 		tsec->create_sid = isec->sid;
3996 	return ret;
3997 }
3998 
3999 static int selinux_kernel_module_request(char *kmod_name)
4000 {
4001 	struct common_audit_data ad;
4002 
4003 	ad.type = LSM_AUDIT_DATA_KMOD;
4004 	ad.u.kmod_name = kmod_name;
4005 
4006 	return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4007 			    SYSTEM__MODULE_REQUEST, &ad);
4008 }
4009 
4010 static int selinux_kernel_module_from_file(struct file *file)
4011 {
4012 	struct common_audit_data ad;
4013 	struct inode_security_struct *isec;
4014 	struct file_security_struct *fsec;
4015 	u32 sid = current_sid();
4016 	int rc;
4017 
4018 	/* init_module */
4019 	if (file == NULL)
4020 		return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
4021 					SYSTEM__MODULE_LOAD, NULL);
4022 
4023 	/* finit_module */
4024 
4025 	ad.type = LSM_AUDIT_DATA_FILE;
4026 	ad.u.file = file;
4027 
4028 	fsec = selinux_file(file);
4029 	if (sid != fsec->sid) {
4030 		rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4031 		if (rc)
4032 			return rc;
4033 	}
4034 
4035 	isec = inode_security(file_inode(file));
4036 	return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
4037 				SYSTEM__MODULE_LOAD, &ad);
4038 }
4039 
4040 static int selinux_kernel_read_file(struct file *file,
4041 				    enum kernel_read_file_id id,
4042 				    bool contents)
4043 {
4044 	int rc = 0;
4045 
4046 	switch (id) {
4047 	case READING_MODULE:
4048 		rc = selinux_kernel_module_from_file(contents ? file : NULL);
4049 		break;
4050 	default:
4051 		break;
4052 	}
4053 
4054 	return rc;
4055 }
4056 
4057 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4058 {
4059 	int rc = 0;
4060 
4061 	switch (id) {
4062 	case LOADING_MODULE:
4063 		rc = selinux_kernel_module_from_file(NULL);
4064 		break;
4065 	default:
4066 		break;
4067 	}
4068 
4069 	return rc;
4070 }
4071 
4072 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4073 {
4074 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4075 			    PROCESS__SETPGID, NULL);
4076 }
4077 
4078 static int selinux_task_getpgid(struct task_struct *p)
4079 {
4080 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4081 			    PROCESS__GETPGID, NULL);
4082 }
4083 
4084 static int selinux_task_getsid(struct task_struct *p)
4085 {
4086 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4087 			    PROCESS__GETSESSION, NULL);
4088 }
4089 
4090 static void selinux_current_getsecid_subj(u32 *secid)
4091 {
4092 	*secid = current_sid();
4093 }
4094 
4095 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid)
4096 {
4097 	*secid = task_sid_obj(p);
4098 }
4099 
4100 static int selinux_task_setnice(struct task_struct *p, int nice)
4101 {
4102 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4103 			    PROCESS__SETSCHED, NULL);
4104 }
4105 
4106 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4107 {
4108 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4109 			    PROCESS__SETSCHED, NULL);
4110 }
4111 
4112 static int selinux_task_getioprio(struct task_struct *p)
4113 {
4114 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4115 			    PROCESS__GETSCHED, NULL);
4116 }
4117 
4118 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4119 				unsigned int flags)
4120 {
4121 	u32 av = 0;
4122 
4123 	if (!flags)
4124 		return 0;
4125 	if (flags & LSM_PRLIMIT_WRITE)
4126 		av |= PROCESS__SETRLIMIT;
4127 	if (flags & LSM_PRLIMIT_READ)
4128 		av |= PROCESS__GETRLIMIT;
4129 	return avc_has_perm(cred_sid(cred), cred_sid(tcred),
4130 			    SECCLASS_PROCESS, av, NULL);
4131 }
4132 
4133 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4134 		struct rlimit *new_rlim)
4135 {
4136 	struct rlimit *old_rlim = p->signal->rlim + resource;
4137 
4138 	/* Control the ability to change the hard limit (whether
4139 	   lowering or raising it), so that the hard limit can
4140 	   later be used as a safe reset point for the soft limit
4141 	   upon context transitions.  See selinux_bprm_committing_creds. */
4142 	if (old_rlim->rlim_max != new_rlim->rlim_max)
4143 		return avc_has_perm(current_sid(), task_sid_obj(p),
4144 				    SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4145 
4146 	return 0;
4147 }
4148 
4149 static int selinux_task_setscheduler(struct task_struct *p)
4150 {
4151 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4152 			    PROCESS__SETSCHED, NULL);
4153 }
4154 
4155 static int selinux_task_getscheduler(struct task_struct *p)
4156 {
4157 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4158 			    PROCESS__GETSCHED, NULL);
4159 }
4160 
4161 static int selinux_task_movememory(struct task_struct *p)
4162 {
4163 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4164 			    PROCESS__SETSCHED, NULL);
4165 }
4166 
4167 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4168 				int sig, const struct cred *cred)
4169 {
4170 	u32 secid;
4171 	u32 perm;
4172 
4173 	if (!sig)
4174 		perm = PROCESS__SIGNULL; /* null signal; existence test */
4175 	else
4176 		perm = signal_to_av(sig);
4177 	if (!cred)
4178 		secid = current_sid();
4179 	else
4180 		secid = cred_sid(cred);
4181 	return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4182 }
4183 
4184 static void selinux_task_to_inode(struct task_struct *p,
4185 				  struct inode *inode)
4186 {
4187 	struct inode_security_struct *isec = selinux_inode(inode);
4188 	u32 sid = task_sid_obj(p);
4189 
4190 	spin_lock(&isec->lock);
4191 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
4192 	isec->sid = sid;
4193 	isec->initialized = LABEL_INITIALIZED;
4194 	spin_unlock(&isec->lock);
4195 }
4196 
4197 static int selinux_userns_create(const struct cred *cred)
4198 {
4199 	u32 sid = current_sid();
4200 
4201 	return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4202 			USER_NAMESPACE__CREATE, NULL);
4203 }
4204 
4205 /* Returns error only if unable to parse addresses */
4206 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4207 			struct common_audit_data *ad, u8 *proto)
4208 {
4209 	int offset, ihlen, ret = -EINVAL;
4210 	struct iphdr _iph, *ih;
4211 
4212 	offset = skb_network_offset(skb);
4213 	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4214 	if (ih == NULL)
4215 		goto out;
4216 
4217 	ihlen = ih->ihl * 4;
4218 	if (ihlen < sizeof(_iph))
4219 		goto out;
4220 
4221 	ad->u.net->v4info.saddr = ih->saddr;
4222 	ad->u.net->v4info.daddr = ih->daddr;
4223 	ret = 0;
4224 
4225 	if (proto)
4226 		*proto = ih->protocol;
4227 
4228 	switch (ih->protocol) {
4229 	case IPPROTO_TCP: {
4230 		struct tcphdr _tcph, *th;
4231 
4232 		if (ntohs(ih->frag_off) & IP_OFFSET)
4233 			break;
4234 
4235 		offset += ihlen;
4236 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4237 		if (th == NULL)
4238 			break;
4239 
4240 		ad->u.net->sport = th->source;
4241 		ad->u.net->dport = th->dest;
4242 		break;
4243 	}
4244 
4245 	case IPPROTO_UDP: {
4246 		struct udphdr _udph, *uh;
4247 
4248 		if (ntohs(ih->frag_off) & IP_OFFSET)
4249 			break;
4250 
4251 		offset += ihlen;
4252 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4253 		if (uh == NULL)
4254 			break;
4255 
4256 		ad->u.net->sport = uh->source;
4257 		ad->u.net->dport = uh->dest;
4258 		break;
4259 	}
4260 
4261 	case IPPROTO_DCCP: {
4262 		struct dccp_hdr _dccph, *dh;
4263 
4264 		if (ntohs(ih->frag_off) & IP_OFFSET)
4265 			break;
4266 
4267 		offset += ihlen;
4268 		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4269 		if (dh == NULL)
4270 			break;
4271 
4272 		ad->u.net->sport = dh->dccph_sport;
4273 		ad->u.net->dport = dh->dccph_dport;
4274 		break;
4275 	}
4276 
4277 #if IS_ENABLED(CONFIG_IP_SCTP)
4278 	case IPPROTO_SCTP: {
4279 		struct sctphdr _sctph, *sh;
4280 
4281 		if (ntohs(ih->frag_off) & IP_OFFSET)
4282 			break;
4283 
4284 		offset += ihlen;
4285 		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4286 		if (sh == NULL)
4287 			break;
4288 
4289 		ad->u.net->sport = sh->source;
4290 		ad->u.net->dport = sh->dest;
4291 		break;
4292 	}
4293 #endif
4294 	default:
4295 		break;
4296 	}
4297 out:
4298 	return ret;
4299 }
4300 
4301 #if IS_ENABLED(CONFIG_IPV6)
4302 
4303 /* Returns error only if unable to parse addresses */
4304 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4305 			struct common_audit_data *ad, u8 *proto)
4306 {
4307 	u8 nexthdr;
4308 	int ret = -EINVAL, offset;
4309 	struct ipv6hdr _ipv6h, *ip6;
4310 	__be16 frag_off;
4311 
4312 	offset = skb_network_offset(skb);
4313 	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4314 	if (ip6 == NULL)
4315 		goto out;
4316 
4317 	ad->u.net->v6info.saddr = ip6->saddr;
4318 	ad->u.net->v6info.daddr = ip6->daddr;
4319 	ret = 0;
4320 
4321 	nexthdr = ip6->nexthdr;
4322 	offset += sizeof(_ipv6h);
4323 	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4324 	if (offset < 0)
4325 		goto out;
4326 
4327 	if (proto)
4328 		*proto = nexthdr;
4329 
4330 	switch (nexthdr) {
4331 	case IPPROTO_TCP: {
4332 		struct tcphdr _tcph, *th;
4333 
4334 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4335 		if (th == NULL)
4336 			break;
4337 
4338 		ad->u.net->sport = th->source;
4339 		ad->u.net->dport = th->dest;
4340 		break;
4341 	}
4342 
4343 	case IPPROTO_UDP: {
4344 		struct udphdr _udph, *uh;
4345 
4346 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4347 		if (uh == NULL)
4348 			break;
4349 
4350 		ad->u.net->sport = uh->source;
4351 		ad->u.net->dport = uh->dest;
4352 		break;
4353 	}
4354 
4355 	case IPPROTO_DCCP: {
4356 		struct dccp_hdr _dccph, *dh;
4357 
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 		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4372 		if (sh == NULL)
4373 			break;
4374 
4375 		ad->u.net->sport = sh->source;
4376 		ad->u.net->dport = sh->dest;
4377 		break;
4378 	}
4379 #endif
4380 	/* includes fragments */
4381 	default:
4382 		break;
4383 	}
4384 out:
4385 	return ret;
4386 }
4387 
4388 #endif /* IPV6 */
4389 
4390 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4391 			     char **_addrp, int src, u8 *proto)
4392 {
4393 	char *addrp;
4394 	int ret;
4395 
4396 	switch (ad->u.net->family) {
4397 	case PF_INET:
4398 		ret = selinux_parse_skb_ipv4(skb, ad, proto);
4399 		if (ret)
4400 			goto parse_error;
4401 		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4402 				       &ad->u.net->v4info.daddr);
4403 		goto okay;
4404 
4405 #if IS_ENABLED(CONFIG_IPV6)
4406 	case PF_INET6:
4407 		ret = selinux_parse_skb_ipv6(skb, ad, proto);
4408 		if (ret)
4409 			goto parse_error;
4410 		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4411 				       &ad->u.net->v6info.daddr);
4412 		goto okay;
4413 #endif	/* IPV6 */
4414 	default:
4415 		addrp = NULL;
4416 		goto okay;
4417 	}
4418 
4419 parse_error:
4420 	pr_warn(
4421 	       "SELinux: failure in selinux_parse_skb(),"
4422 	       " unable to parse packet\n");
4423 	return ret;
4424 
4425 okay:
4426 	if (_addrp)
4427 		*_addrp = addrp;
4428 	return 0;
4429 }
4430 
4431 /**
4432  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4433  * @skb: the packet
4434  * @family: protocol family
4435  * @sid: the packet's peer label SID
4436  *
4437  * Description:
4438  * Check the various different forms of network peer labeling and determine
4439  * the peer label/SID for the packet; most of the magic actually occurs in
4440  * the security server function security_net_peersid_cmp().  The function
4441  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4442  * or -EACCES if @sid is invalid due to inconsistencies with the different
4443  * peer labels.
4444  *
4445  */
4446 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4447 {
4448 	int err;
4449 	u32 xfrm_sid;
4450 	u32 nlbl_sid;
4451 	u32 nlbl_type;
4452 
4453 	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4454 	if (unlikely(err))
4455 		return -EACCES;
4456 	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4457 	if (unlikely(err))
4458 		return -EACCES;
4459 
4460 	err = security_net_peersid_resolve(nlbl_sid,
4461 					   nlbl_type, xfrm_sid, sid);
4462 	if (unlikely(err)) {
4463 		pr_warn(
4464 		       "SELinux: failure in selinux_skb_peerlbl_sid(),"
4465 		       " unable to determine packet's peer label\n");
4466 		return -EACCES;
4467 	}
4468 
4469 	return 0;
4470 }
4471 
4472 /**
4473  * selinux_conn_sid - Determine the child socket label for a connection
4474  * @sk_sid: the parent socket's SID
4475  * @skb_sid: the packet's SID
4476  * @conn_sid: the resulting connection SID
4477  *
4478  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4479  * combined with the MLS information from @skb_sid in order to create
4480  * @conn_sid.  If @skb_sid is not valid then @conn_sid is simply a copy
4481  * of @sk_sid.  Returns zero on success, negative values on failure.
4482  *
4483  */
4484 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4485 {
4486 	int err = 0;
4487 
4488 	if (skb_sid != SECSID_NULL)
4489 		err = security_sid_mls_copy(sk_sid, skb_sid,
4490 					    conn_sid);
4491 	else
4492 		*conn_sid = sk_sid;
4493 
4494 	return err;
4495 }
4496 
4497 /* socket security operations */
4498 
4499 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4500 				 u16 secclass, u32 *socksid)
4501 {
4502 	if (tsec->sockcreate_sid > SECSID_NULL) {
4503 		*socksid = tsec->sockcreate_sid;
4504 		return 0;
4505 	}
4506 
4507 	return security_transition_sid(tsec->sid, tsec->sid,
4508 				       secclass, NULL, socksid);
4509 }
4510 
4511 static int sock_has_perm(struct sock *sk, u32 perms)
4512 {
4513 	struct sk_security_struct *sksec = sk->sk_security;
4514 	struct common_audit_data ad;
4515 	struct lsm_network_audit net = {0,};
4516 
4517 	if (sksec->sid == SECINITSID_KERNEL)
4518 		return 0;
4519 
4520 	/*
4521 	 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
4522 	 * inherited the kernel context from early boot used to be skipped
4523 	 * here, so preserve that behavior unless the capability is set.
4524 	 *
4525 	 * By setting the capability the policy signals that it is ready
4526 	 * for this quirk to be fixed. Note that sockets created by a kernel
4527 	 * thread or a usermode helper executed without a transition will
4528 	 * still be skipped in this check regardless of the policycap
4529 	 * setting.
4530 	 */
4531 	if (!selinux_policycap_userspace_initial_context() &&
4532 	    sksec->sid == SECINITSID_INIT)
4533 		return 0;
4534 
4535 	ad.type = LSM_AUDIT_DATA_NET;
4536 	ad.u.net = &net;
4537 	ad.u.net->sk = sk;
4538 
4539 	return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
4540 			    &ad);
4541 }
4542 
4543 static int selinux_socket_create(int family, int type,
4544 				 int protocol, int kern)
4545 {
4546 	const struct task_security_struct *tsec = selinux_cred(current_cred());
4547 	u32 newsid;
4548 	u16 secclass;
4549 	int rc;
4550 
4551 	if (kern)
4552 		return 0;
4553 
4554 	secclass = socket_type_to_security_class(family, type, protocol);
4555 	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4556 	if (rc)
4557 		return rc;
4558 
4559 	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4560 }
4561 
4562 static int selinux_socket_post_create(struct socket *sock, int family,
4563 				      int type, int protocol, int kern)
4564 {
4565 	const struct task_security_struct *tsec = selinux_cred(current_cred());
4566 	struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4567 	struct sk_security_struct *sksec;
4568 	u16 sclass = socket_type_to_security_class(family, type, protocol);
4569 	u32 sid = SECINITSID_KERNEL;
4570 	int err = 0;
4571 
4572 	if (!kern) {
4573 		err = socket_sockcreate_sid(tsec, sclass, &sid);
4574 		if (err)
4575 			return err;
4576 	}
4577 
4578 	isec->sclass = sclass;
4579 	isec->sid = sid;
4580 	isec->initialized = LABEL_INITIALIZED;
4581 
4582 	if (sock->sk) {
4583 		sksec = sock->sk->sk_security;
4584 		sksec->sclass = sclass;
4585 		sksec->sid = sid;
4586 		/* Allows detection of the first association on this socket */
4587 		if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4588 			sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4589 
4590 		err = selinux_netlbl_socket_post_create(sock->sk, family);
4591 	}
4592 
4593 	return err;
4594 }
4595 
4596 static int selinux_socket_socketpair(struct socket *socka,
4597 				     struct socket *sockb)
4598 {
4599 	struct sk_security_struct *sksec_a = socka->sk->sk_security;
4600 	struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4601 
4602 	sksec_a->peer_sid = sksec_b->sid;
4603 	sksec_b->peer_sid = sksec_a->sid;
4604 
4605 	return 0;
4606 }
4607 
4608 /* Range of port numbers used to automatically bind.
4609    Need to determine whether we should perform a name_bind
4610    permission check between the socket and the port number. */
4611 
4612 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4613 {
4614 	struct sock *sk = sock->sk;
4615 	struct sk_security_struct *sksec = sk->sk_security;
4616 	u16 family;
4617 	int err;
4618 
4619 	err = sock_has_perm(sk, SOCKET__BIND);
4620 	if (err)
4621 		goto out;
4622 
4623 	/* If PF_INET or PF_INET6, check name_bind permission for the port. */
4624 	family = sk->sk_family;
4625 	if (family == PF_INET || family == PF_INET6) {
4626 		char *addrp;
4627 		struct common_audit_data ad;
4628 		struct lsm_network_audit net = {0,};
4629 		struct sockaddr_in *addr4 = NULL;
4630 		struct sockaddr_in6 *addr6 = NULL;
4631 		u16 family_sa;
4632 		unsigned short snum;
4633 		u32 sid, node_perm;
4634 
4635 		/*
4636 		 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4637 		 * that validates multiple binding addresses. Because of this
4638 		 * need to check address->sa_family as it is possible to have
4639 		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4640 		 */
4641 		if (addrlen < offsetofend(struct sockaddr, sa_family))
4642 			return -EINVAL;
4643 		family_sa = address->sa_family;
4644 		switch (family_sa) {
4645 		case AF_UNSPEC:
4646 		case AF_INET:
4647 			if (addrlen < sizeof(struct sockaddr_in))
4648 				return -EINVAL;
4649 			addr4 = (struct sockaddr_in *)address;
4650 			if (family_sa == AF_UNSPEC) {
4651 				/* see __inet_bind(), we only want to allow
4652 				 * AF_UNSPEC if the address is INADDR_ANY
4653 				 */
4654 				if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4655 					goto err_af;
4656 				family_sa = AF_INET;
4657 			}
4658 			snum = ntohs(addr4->sin_port);
4659 			addrp = (char *)&addr4->sin_addr.s_addr;
4660 			break;
4661 		case AF_INET6:
4662 			if (addrlen < SIN6_LEN_RFC2133)
4663 				return -EINVAL;
4664 			addr6 = (struct sockaddr_in6 *)address;
4665 			snum = ntohs(addr6->sin6_port);
4666 			addrp = (char *)&addr6->sin6_addr.s6_addr;
4667 			break;
4668 		default:
4669 			goto err_af;
4670 		}
4671 
4672 		ad.type = LSM_AUDIT_DATA_NET;
4673 		ad.u.net = &net;
4674 		ad.u.net->sport = htons(snum);
4675 		ad.u.net->family = family_sa;
4676 
4677 		if (snum) {
4678 			int low, high;
4679 
4680 			inet_get_local_port_range(sock_net(sk), &low, &high);
4681 
4682 			if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4683 			    snum < low || snum > high) {
4684 				err = sel_netport_sid(sk->sk_protocol,
4685 						      snum, &sid);
4686 				if (err)
4687 					goto out;
4688 				err = avc_has_perm(sksec->sid, sid,
4689 						   sksec->sclass,
4690 						   SOCKET__NAME_BIND, &ad);
4691 				if (err)
4692 					goto out;
4693 			}
4694 		}
4695 
4696 		switch (sksec->sclass) {
4697 		case SECCLASS_TCP_SOCKET:
4698 			node_perm = TCP_SOCKET__NODE_BIND;
4699 			break;
4700 
4701 		case SECCLASS_UDP_SOCKET:
4702 			node_perm = UDP_SOCKET__NODE_BIND;
4703 			break;
4704 
4705 		case SECCLASS_DCCP_SOCKET:
4706 			node_perm = DCCP_SOCKET__NODE_BIND;
4707 			break;
4708 
4709 		case SECCLASS_SCTP_SOCKET:
4710 			node_perm = SCTP_SOCKET__NODE_BIND;
4711 			break;
4712 
4713 		default:
4714 			node_perm = RAWIP_SOCKET__NODE_BIND;
4715 			break;
4716 		}
4717 
4718 		err = sel_netnode_sid(addrp, family_sa, &sid);
4719 		if (err)
4720 			goto out;
4721 
4722 		if (family_sa == AF_INET)
4723 			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4724 		else
4725 			ad.u.net->v6info.saddr = addr6->sin6_addr;
4726 
4727 		err = avc_has_perm(sksec->sid, sid,
4728 				   sksec->sclass, node_perm, &ad);
4729 		if (err)
4730 			goto out;
4731 	}
4732 out:
4733 	return err;
4734 err_af:
4735 	/* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4736 	if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4737 		return -EINVAL;
4738 	return -EAFNOSUPPORT;
4739 }
4740 
4741 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4742  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4743  */
4744 static int selinux_socket_connect_helper(struct socket *sock,
4745 					 struct sockaddr *address, int addrlen)
4746 {
4747 	struct sock *sk = sock->sk;
4748 	struct sk_security_struct *sksec = sk->sk_security;
4749 	int err;
4750 
4751 	err = sock_has_perm(sk, SOCKET__CONNECT);
4752 	if (err)
4753 		return err;
4754 	if (addrlen < offsetofend(struct sockaddr, sa_family))
4755 		return -EINVAL;
4756 
4757 	/* connect(AF_UNSPEC) has special handling, as it is a documented
4758 	 * way to disconnect the socket
4759 	 */
4760 	if (address->sa_family == AF_UNSPEC)
4761 		return 0;
4762 
4763 	/*
4764 	 * If a TCP, DCCP or SCTP socket, check name_connect permission
4765 	 * for the port.
4766 	 */
4767 	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4768 	    sksec->sclass == SECCLASS_DCCP_SOCKET ||
4769 	    sksec->sclass == SECCLASS_SCTP_SOCKET) {
4770 		struct common_audit_data ad;
4771 		struct lsm_network_audit net = {0,};
4772 		struct sockaddr_in *addr4 = NULL;
4773 		struct sockaddr_in6 *addr6 = NULL;
4774 		unsigned short snum;
4775 		u32 sid, perm;
4776 
4777 		/* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4778 		 * that validates multiple connect addresses. Because of this
4779 		 * need to check address->sa_family as it is possible to have
4780 		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4781 		 */
4782 		switch (address->sa_family) {
4783 		case AF_INET:
4784 			addr4 = (struct sockaddr_in *)address;
4785 			if (addrlen < sizeof(struct sockaddr_in))
4786 				return -EINVAL;
4787 			snum = ntohs(addr4->sin_port);
4788 			break;
4789 		case AF_INET6:
4790 			addr6 = (struct sockaddr_in6 *)address;
4791 			if (addrlen < SIN6_LEN_RFC2133)
4792 				return -EINVAL;
4793 			snum = ntohs(addr6->sin6_port);
4794 			break;
4795 		default:
4796 			/* Note that SCTP services expect -EINVAL, whereas
4797 			 * others expect -EAFNOSUPPORT.
4798 			 */
4799 			if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4800 				return -EINVAL;
4801 			else
4802 				return -EAFNOSUPPORT;
4803 		}
4804 
4805 		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4806 		if (err)
4807 			return err;
4808 
4809 		switch (sksec->sclass) {
4810 		case SECCLASS_TCP_SOCKET:
4811 			perm = TCP_SOCKET__NAME_CONNECT;
4812 			break;
4813 		case SECCLASS_DCCP_SOCKET:
4814 			perm = DCCP_SOCKET__NAME_CONNECT;
4815 			break;
4816 		case SECCLASS_SCTP_SOCKET:
4817 			perm = SCTP_SOCKET__NAME_CONNECT;
4818 			break;
4819 		}
4820 
4821 		ad.type = LSM_AUDIT_DATA_NET;
4822 		ad.u.net = &net;
4823 		ad.u.net->dport = htons(snum);
4824 		ad.u.net->family = address->sa_family;
4825 		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4826 		if (err)
4827 			return err;
4828 	}
4829 
4830 	return 0;
4831 }
4832 
4833 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4834 static int selinux_socket_connect(struct socket *sock,
4835 				  struct sockaddr *address, int addrlen)
4836 {
4837 	int err;
4838 	struct sock *sk = sock->sk;
4839 
4840 	err = selinux_socket_connect_helper(sock, address, addrlen);
4841 	if (err)
4842 		return err;
4843 
4844 	return selinux_netlbl_socket_connect(sk, address);
4845 }
4846 
4847 static int selinux_socket_listen(struct socket *sock, int backlog)
4848 {
4849 	return sock_has_perm(sock->sk, SOCKET__LISTEN);
4850 }
4851 
4852 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4853 {
4854 	int err;
4855 	struct inode_security_struct *isec;
4856 	struct inode_security_struct *newisec;
4857 	u16 sclass;
4858 	u32 sid;
4859 
4860 	err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4861 	if (err)
4862 		return err;
4863 
4864 	isec = inode_security_novalidate(SOCK_INODE(sock));
4865 	spin_lock(&isec->lock);
4866 	sclass = isec->sclass;
4867 	sid = isec->sid;
4868 	spin_unlock(&isec->lock);
4869 
4870 	newisec = inode_security_novalidate(SOCK_INODE(newsock));
4871 	newisec->sclass = sclass;
4872 	newisec->sid = sid;
4873 	newisec->initialized = LABEL_INITIALIZED;
4874 
4875 	return 0;
4876 }
4877 
4878 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4879 				  int size)
4880 {
4881 	return sock_has_perm(sock->sk, SOCKET__WRITE);
4882 }
4883 
4884 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4885 				  int size, int flags)
4886 {
4887 	return sock_has_perm(sock->sk, SOCKET__READ);
4888 }
4889 
4890 static int selinux_socket_getsockname(struct socket *sock)
4891 {
4892 	return sock_has_perm(sock->sk, SOCKET__GETATTR);
4893 }
4894 
4895 static int selinux_socket_getpeername(struct socket *sock)
4896 {
4897 	return sock_has_perm(sock->sk, SOCKET__GETATTR);
4898 }
4899 
4900 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4901 {
4902 	int err;
4903 
4904 	err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4905 	if (err)
4906 		return err;
4907 
4908 	return selinux_netlbl_socket_setsockopt(sock, level, optname);
4909 }
4910 
4911 static int selinux_socket_getsockopt(struct socket *sock, int level,
4912 				     int optname)
4913 {
4914 	return sock_has_perm(sock->sk, SOCKET__GETOPT);
4915 }
4916 
4917 static int selinux_socket_shutdown(struct socket *sock, int how)
4918 {
4919 	return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4920 }
4921 
4922 static int selinux_socket_unix_stream_connect(struct sock *sock,
4923 					      struct sock *other,
4924 					      struct sock *newsk)
4925 {
4926 	struct sk_security_struct *sksec_sock = sock->sk_security;
4927 	struct sk_security_struct *sksec_other = other->sk_security;
4928 	struct sk_security_struct *sksec_new = newsk->sk_security;
4929 	struct common_audit_data ad;
4930 	struct lsm_network_audit net = {0,};
4931 	int err;
4932 
4933 	ad.type = LSM_AUDIT_DATA_NET;
4934 	ad.u.net = &net;
4935 	ad.u.net->sk = other;
4936 
4937 	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4938 			   sksec_other->sclass,
4939 			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4940 	if (err)
4941 		return err;
4942 
4943 	/* server child socket */
4944 	sksec_new->peer_sid = sksec_sock->sid;
4945 	err = security_sid_mls_copy(sksec_other->sid,
4946 				    sksec_sock->sid, &sksec_new->sid);
4947 	if (err)
4948 		return err;
4949 
4950 	/* connecting socket */
4951 	sksec_sock->peer_sid = sksec_new->sid;
4952 
4953 	return 0;
4954 }
4955 
4956 static int selinux_socket_unix_may_send(struct socket *sock,
4957 					struct socket *other)
4958 {
4959 	struct sk_security_struct *ssec = sock->sk->sk_security;
4960 	struct sk_security_struct *osec = other->sk->sk_security;
4961 	struct common_audit_data ad;
4962 	struct lsm_network_audit net = {0,};
4963 
4964 	ad.type = LSM_AUDIT_DATA_NET;
4965 	ad.u.net = &net;
4966 	ad.u.net->sk = other->sk;
4967 
4968 	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4969 			    &ad);
4970 }
4971 
4972 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4973 				    char *addrp, u16 family, u32 peer_sid,
4974 				    struct common_audit_data *ad)
4975 {
4976 	int err;
4977 	u32 if_sid;
4978 	u32 node_sid;
4979 
4980 	err = sel_netif_sid(ns, ifindex, &if_sid);
4981 	if (err)
4982 		return err;
4983 	err = avc_has_perm(peer_sid, if_sid,
4984 			   SECCLASS_NETIF, NETIF__INGRESS, ad);
4985 	if (err)
4986 		return err;
4987 
4988 	err = sel_netnode_sid(addrp, family, &node_sid);
4989 	if (err)
4990 		return err;
4991 	return avc_has_perm(peer_sid, node_sid,
4992 			    SECCLASS_NODE, NODE__RECVFROM, ad);
4993 }
4994 
4995 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4996 				       u16 family)
4997 {
4998 	int err = 0;
4999 	struct sk_security_struct *sksec = sk->sk_security;
5000 	u32 sk_sid = sksec->sid;
5001 	struct common_audit_data ad;
5002 	struct lsm_network_audit net = {0,};
5003 	char *addrp;
5004 
5005 	ad.type = LSM_AUDIT_DATA_NET;
5006 	ad.u.net = &net;
5007 	ad.u.net->netif = skb->skb_iif;
5008 	ad.u.net->family = family;
5009 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5010 	if (err)
5011 		return err;
5012 
5013 	if (selinux_secmark_enabled()) {
5014 		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5015 				   PACKET__RECV, &ad);
5016 		if (err)
5017 			return err;
5018 	}
5019 
5020 	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5021 	if (err)
5022 		return err;
5023 	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5024 
5025 	return err;
5026 }
5027 
5028 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5029 {
5030 	int err;
5031 	struct sk_security_struct *sksec = sk->sk_security;
5032 	u16 family = sk->sk_family;
5033 	u32 sk_sid = sksec->sid;
5034 	struct common_audit_data ad;
5035 	struct lsm_network_audit net = {0,};
5036 	char *addrp;
5037 	u8 secmark_active;
5038 	u8 peerlbl_active;
5039 
5040 	if (family != PF_INET && family != PF_INET6)
5041 		return 0;
5042 
5043 	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
5044 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5045 		family = PF_INET;
5046 
5047 	/* If any sort of compatibility mode is enabled then handoff processing
5048 	 * to the selinux_sock_rcv_skb_compat() function to deal with the
5049 	 * special handling.  We do this in an attempt to keep this function
5050 	 * as fast and as clean as possible. */
5051 	if (!selinux_policycap_netpeer())
5052 		return selinux_sock_rcv_skb_compat(sk, skb, family);
5053 
5054 	secmark_active = selinux_secmark_enabled();
5055 	peerlbl_active = selinux_peerlbl_enabled();
5056 	if (!secmark_active && !peerlbl_active)
5057 		return 0;
5058 
5059 	ad.type = LSM_AUDIT_DATA_NET;
5060 	ad.u.net = &net;
5061 	ad.u.net->netif = skb->skb_iif;
5062 	ad.u.net->family = family;
5063 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5064 	if (err)
5065 		return err;
5066 
5067 	if (peerlbl_active) {
5068 		u32 peer_sid;
5069 
5070 		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5071 		if (err)
5072 			return err;
5073 		err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5074 					       addrp, family, peer_sid, &ad);
5075 		if (err) {
5076 			selinux_netlbl_err(skb, family, err, 0);
5077 			return err;
5078 		}
5079 		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
5080 				   PEER__RECV, &ad);
5081 		if (err) {
5082 			selinux_netlbl_err(skb, family, err, 0);
5083 			return err;
5084 		}
5085 	}
5086 
5087 	if (secmark_active) {
5088 		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5089 				   PACKET__RECV, &ad);
5090 		if (err)
5091 			return err;
5092 	}
5093 
5094 	return err;
5095 }
5096 
5097 static int selinux_socket_getpeersec_stream(struct socket *sock,
5098 					    sockptr_t optval, sockptr_t optlen,
5099 					    unsigned int len)
5100 {
5101 	int err = 0;
5102 	char *scontext = NULL;
5103 	u32 scontext_len;
5104 	struct sk_security_struct *sksec = sock->sk->sk_security;
5105 	u32 peer_sid = SECSID_NULL;
5106 
5107 	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5108 	    sksec->sclass == SECCLASS_TCP_SOCKET ||
5109 	    sksec->sclass == SECCLASS_SCTP_SOCKET)
5110 		peer_sid = sksec->peer_sid;
5111 	if (peer_sid == SECSID_NULL)
5112 		return -ENOPROTOOPT;
5113 
5114 	err = security_sid_to_context(peer_sid, &scontext,
5115 				      &scontext_len);
5116 	if (err)
5117 		return err;
5118 	if (scontext_len > len) {
5119 		err = -ERANGE;
5120 		goto out_len;
5121 	}
5122 
5123 	if (copy_to_sockptr(optval, scontext, scontext_len))
5124 		err = -EFAULT;
5125 out_len:
5126 	if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5127 		err = -EFAULT;
5128 	kfree(scontext);
5129 	return err;
5130 }
5131 
5132 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5133 {
5134 	u32 peer_secid = SECSID_NULL;
5135 	u16 family;
5136 	struct inode_security_struct *isec;
5137 
5138 	if (skb && skb->protocol == htons(ETH_P_IP))
5139 		family = PF_INET;
5140 	else if (skb && skb->protocol == htons(ETH_P_IPV6))
5141 		family = PF_INET6;
5142 	else if (sock)
5143 		family = sock->sk->sk_family;
5144 	else
5145 		goto out;
5146 
5147 	if (sock && family == PF_UNIX) {
5148 		isec = inode_security_novalidate(SOCK_INODE(sock));
5149 		peer_secid = isec->sid;
5150 	} else if (skb)
5151 		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5152 
5153 out:
5154 	*secid = peer_secid;
5155 	if (peer_secid == SECSID_NULL)
5156 		return -EINVAL;
5157 	return 0;
5158 }
5159 
5160 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5161 {
5162 	struct sk_security_struct *sksec;
5163 
5164 	sksec = kzalloc(sizeof(*sksec), priority);
5165 	if (!sksec)
5166 		return -ENOMEM;
5167 
5168 	sksec->peer_sid = SECINITSID_UNLABELED;
5169 	sksec->sid = SECINITSID_UNLABELED;
5170 	sksec->sclass = SECCLASS_SOCKET;
5171 	selinux_netlbl_sk_security_reset(sksec);
5172 	sk->sk_security = sksec;
5173 
5174 	return 0;
5175 }
5176 
5177 static void selinux_sk_free_security(struct sock *sk)
5178 {
5179 	struct sk_security_struct *sksec = sk->sk_security;
5180 
5181 	sk->sk_security = NULL;
5182 	selinux_netlbl_sk_security_free(sksec);
5183 	kfree(sksec);
5184 }
5185 
5186 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5187 {
5188 	struct sk_security_struct *sksec = sk->sk_security;
5189 	struct sk_security_struct *newsksec = newsk->sk_security;
5190 
5191 	newsksec->sid = sksec->sid;
5192 	newsksec->peer_sid = sksec->peer_sid;
5193 	newsksec->sclass = sksec->sclass;
5194 
5195 	selinux_netlbl_sk_security_reset(newsksec);
5196 }
5197 
5198 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5199 {
5200 	if (!sk)
5201 		*secid = SECINITSID_ANY_SOCKET;
5202 	else {
5203 		struct sk_security_struct *sksec = sk->sk_security;
5204 
5205 		*secid = sksec->sid;
5206 	}
5207 }
5208 
5209 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5210 {
5211 	struct inode_security_struct *isec =
5212 		inode_security_novalidate(SOCK_INODE(parent));
5213 	struct sk_security_struct *sksec = sk->sk_security;
5214 
5215 	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5216 	    sk->sk_family == PF_UNIX)
5217 		isec->sid = sksec->sid;
5218 	sksec->sclass = isec->sclass;
5219 }
5220 
5221 /*
5222  * Determines peer_secid for the asoc and updates socket's peer label
5223  * if it's the first association on the socket.
5224  */
5225 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5226 					  struct sk_buff *skb)
5227 {
5228 	struct sock *sk = asoc->base.sk;
5229 	u16 family = sk->sk_family;
5230 	struct sk_security_struct *sksec = sk->sk_security;
5231 	struct common_audit_data ad;
5232 	struct lsm_network_audit net = {0,};
5233 	int err;
5234 
5235 	/* handle mapped IPv4 packets arriving via IPv6 sockets */
5236 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5237 		family = PF_INET;
5238 
5239 	if (selinux_peerlbl_enabled()) {
5240 		asoc->peer_secid = SECSID_NULL;
5241 
5242 		/* This will return peer_sid = SECSID_NULL if there are
5243 		 * no peer labels, see security_net_peersid_resolve().
5244 		 */
5245 		err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5246 		if (err)
5247 			return err;
5248 
5249 		if (asoc->peer_secid == SECSID_NULL)
5250 			asoc->peer_secid = SECINITSID_UNLABELED;
5251 	} else {
5252 		asoc->peer_secid = SECINITSID_UNLABELED;
5253 	}
5254 
5255 	if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5256 		sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5257 
5258 		/* Here as first association on socket. As the peer SID
5259 		 * was allowed by peer recv (and the netif/node checks),
5260 		 * then it is approved by policy and used as the primary
5261 		 * peer SID for getpeercon(3).
5262 		 */
5263 		sksec->peer_sid = asoc->peer_secid;
5264 	} else if (sksec->peer_sid != asoc->peer_secid) {
5265 		/* Other association peer SIDs are checked to enforce
5266 		 * consistency among the peer SIDs.
5267 		 */
5268 		ad.type = LSM_AUDIT_DATA_NET;
5269 		ad.u.net = &net;
5270 		ad.u.net->sk = asoc->base.sk;
5271 		err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5272 				   sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5273 				   &ad);
5274 		if (err)
5275 			return err;
5276 	}
5277 	return 0;
5278 }
5279 
5280 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5281  * happens on an incoming connect(2), sctp_connectx(3) or
5282  * sctp_sendmsg(3) (with no association already present).
5283  */
5284 static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5285 				      struct sk_buff *skb)
5286 {
5287 	struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5288 	u32 conn_sid;
5289 	int err;
5290 
5291 	if (!selinux_policycap_extsockclass())
5292 		return 0;
5293 
5294 	err = selinux_sctp_process_new_assoc(asoc, skb);
5295 	if (err)
5296 		return err;
5297 
5298 	/* Compute the MLS component for the connection and store
5299 	 * the information in asoc. This will be used by SCTP TCP type
5300 	 * sockets and peeled off connections as they cause a new
5301 	 * socket to be generated. selinux_sctp_sk_clone() will then
5302 	 * plug this into the new socket.
5303 	 */
5304 	err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5305 	if (err)
5306 		return err;
5307 
5308 	asoc->secid = conn_sid;
5309 
5310 	/* Set any NetLabel labels including CIPSO/CALIPSO options. */
5311 	return selinux_netlbl_sctp_assoc_request(asoc, skb);
5312 }
5313 
5314 /* Called when SCTP receives a COOKIE ACK chunk as the final
5315  * response to an association request (initited by us).
5316  */
5317 static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5318 					  struct sk_buff *skb)
5319 {
5320 	struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5321 
5322 	if (!selinux_policycap_extsockclass())
5323 		return 0;
5324 
5325 	/* Inherit secid from the parent socket - this will be picked up
5326 	 * by selinux_sctp_sk_clone() if the association gets peeled off
5327 	 * into a new socket.
5328 	 */
5329 	asoc->secid = sksec->sid;
5330 
5331 	return selinux_sctp_process_new_assoc(asoc, skb);
5332 }
5333 
5334 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5335  * based on their @optname.
5336  */
5337 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5338 				     struct sockaddr *address,
5339 				     int addrlen)
5340 {
5341 	int len, err = 0, walk_size = 0;
5342 	void *addr_buf;
5343 	struct sockaddr *addr;
5344 	struct socket *sock;
5345 
5346 	if (!selinux_policycap_extsockclass())
5347 		return 0;
5348 
5349 	/* Process one or more addresses that may be IPv4 or IPv6 */
5350 	sock = sk->sk_socket;
5351 	addr_buf = address;
5352 
5353 	while (walk_size < addrlen) {
5354 		if (walk_size + sizeof(sa_family_t) > addrlen)
5355 			return -EINVAL;
5356 
5357 		addr = addr_buf;
5358 		switch (addr->sa_family) {
5359 		case AF_UNSPEC:
5360 		case AF_INET:
5361 			len = sizeof(struct sockaddr_in);
5362 			break;
5363 		case AF_INET6:
5364 			len = sizeof(struct sockaddr_in6);
5365 			break;
5366 		default:
5367 			return -EINVAL;
5368 		}
5369 
5370 		if (walk_size + len > addrlen)
5371 			return -EINVAL;
5372 
5373 		err = -EINVAL;
5374 		switch (optname) {
5375 		/* Bind checks */
5376 		case SCTP_PRIMARY_ADDR:
5377 		case SCTP_SET_PEER_PRIMARY_ADDR:
5378 		case SCTP_SOCKOPT_BINDX_ADD:
5379 			err = selinux_socket_bind(sock, addr, len);
5380 			break;
5381 		/* Connect checks */
5382 		case SCTP_SOCKOPT_CONNECTX:
5383 		case SCTP_PARAM_SET_PRIMARY:
5384 		case SCTP_PARAM_ADD_IP:
5385 		case SCTP_SENDMSG_CONNECT:
5386 			err = selinux_socket_connect_helper(sock, addr, len);
5387 			if (err)
5388 				return err;
5389 
5390 			/* As selinux_sctp_bind_connect() is called by the
5391 			 * SCTP protocol layer, the socket is already locked,
5392 			 * therefore selinux_netlbl_socket_connect_locked()
5393 			 * is called here. The situations handled are:
5394 			 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5395 			 * whenever a new IP address is added or when a new
5396 			 * primary address is selected.
5397 			 * Note that an SCTP connect(2) call happens before
5398 			 * the SCTP protocol layer and is handled via
5399 			 * selinux_socket_connect().
5400 			 */
5401 			err = selinux_netlbl_socket_connect_locked(sk, addr);
5402 			break;
5403 		}
5404 
5405 		if (err)
5406 			return err;
5407 
5408 		addr_buf += len;
5409 		walk_size += len;
5410 	}
5411 
5412 	return 0;
5413 }
5414 
5415 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5416 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5417 				  struct sock *newsk)
5418 {
5419 	struct sk_security_struct *sksec = sk->sk_security;
5420 	struct sk_security_struct *newsksec = newsk->sk_security;
5421 
5422 	/* If policy does not support SECCLASS_SCTP_SOCKET then call
5423 	 * the non-sctp clone version.
5424 	 */
5425 	if (!selinux_policycap_extsockclass())
5426 		return selinux_sk_clone_security(sk, newsk);
5427 
5428 	newsksec->sid = asoc->secid;
5429 	newsksec->peer_sid = asoc->peer_secid;
5430 	newsksec->sclass = sksec->sclass;
5431 	selinux_netlbl_sctp_sk_clone(sk, newsk);
5432 }
5433 
5434 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5435 {
5436 	struct sk_security_struct *ssksec = ssk->sk_security;
5437 	struct sk_security_struct *sksec = sk->sk_security;
5438 
5439 	ssksec->sclass = sksec->sclass;
5440 	ssksec->sid = sksec->sid;
5441 
5442 	/* replace the existing subflow label deleting the existing one
5443 	 * and re-recreating a new label using the updated context
5444 	 */
5445 	selinux_netlbl_sk_security_free(ssksec);
5446 	return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5447 }
5448 
5449 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5450 				     struct request_sock *req)
5451 {
5452 	struct sk_security_struct *sksec = sk->sk_security;
5453 	int err;
5454 	u16 family = req->rsk_ops->family;
5455 	u32 connsid;
5456 	u32 peersid;
5457 
5458 	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5459 	if (err)
5460 		return err;
5461 	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5462 	if (err)
5463 		return err;
5464 	req->secid = connsid;
5465 	req->peer_secid = peersid;
5466 
5467 	return selinux_netlbl_inet_conn_request(req, family);
5468 }
5469 
5470 static void selinux_inet_csk_clone(struct sock *newsk,
5471 				   const struct request_sock *req)
5472 {
5473 	struct sk_security_struct *newsksec = newsk->sk_security;
5474 
5475 	newsksec->sid = req->secid;
5476 	newsksec->peer_sid = req->peer_secid;
5477 	/* NOTE: Ideally, we should also get the isec->sid for the
5478 	   new socket in sync, but we don't have the isec available yet.
5479 	   So we will wait until sock_graft to do it, by which
5480 	   time it will have been created and available. */
5481 
5482 	/* We don't need to take any sort of lock here as we are the only
5483 	 * thread with access to newsksec */
5484 	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5485 }
5486 
5487 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5488 {
5489 	u16 family = sk->sk_family;
5490 	struct sk_security_struct *sksec = sk->sk_security;
5491 
5492 	/* handle mapped IPv4 packets arriving via IPv6 sockets */
5493 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5494 		family = PF_INET;
5495 
5496 	selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5497 }
5498 
5499 static int selinux_secmark_relabel_packet(u32 sid)
5500 {
5501 	const struct task_security_struct *__tsec;
5502 	u32 tsid;
5503 
5504 	__tsec = selinux_cred(current_cred());
5505 	tsid = __tsec->sid;
5506 
5507 	return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5508 			    NULL);
5509 }
5510 
5511 static void selinux_secmark_refcount_inc(void)
5512 {
5513 	atomic_inc(&selinux_secmark_refcount);
5514 }
5515 
5516 static void selinux_secmark_refcount_dec(void)
5517 {
5518 	atomic_dec(&selinux_secmark_refcount);
5519 }
5520 
5521 static void selinux_req_classify_flow(const struct request_sock *req,
5522 				      struct flowi_common *flic)
5523 {
5524 	flic->flowic_secid = req->secid;
5525 }
5526 
5527 static int selinux_tun_dev_alloc_security(void **security)
5528 {
5529 	struct tun_security_struct *tunsec;
5530 
5531 	tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5532 	if (!tunsec)
5533 		return -ENOMEM;
5534 	tunsec->sid = current_sid();
5535 
5536 	*security = tunsec;
5537 	return 0;
5538 }
5539 
5540 static void selinux_tun_dev_free_security(void *security)
5541 {
5542 	kfree(security);
5543 }
5544 
5545 static int selinux_tun_dev_create(void)
5546 {
5547 	u32 sid = current_sid();
5548 
5549 	/* we aren't taking into account the "sockcreate" SID since the socket
5550 	 * that is being created here is not a socket in the traditional sense,
5551 	 * instead it is a private sock, accessible only to the kernel, and
5552 	 * representing a wide range of network traffic spanning multiple
5553 	 * connections unlike traditional sockets - check the TUN driver to
5554 	 * get a better understanding of why this socket is special */
5555 
5556 	return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5557 			    NULL);
5558 }
5559 
5560 static int selinux_tun_dev_attach_queue(void *security)
5561 {
5562 	struct tun_security_struct *tunsec = security;
5563 
5564 	return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5565 			    TUN_SOCKET__ATTACH_QUEUE, NULL);
5566 }
5567 
5568 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5569 {
5570 	struct tun_security_struct *tunsec = security;
5571 	struct sk_security_struct *sksec = sk->sk_security;
5572 
5573 	/* we don't currently perform any NetLabel based labeling here and it
5574 	 * isn't clear that we would want to do so anyway; while we could apply
5575 	 * labeling without the support of the TUN user the resulting labeled
5576 	 * traffic from the other end of the connection would almost certainly
5577 	 * cause confusion to the TUN user that had no idea network labeling
5578 	 * protocols were being used */
5579 
5580 	sksec->sid = tunsec->sid;
5581 	sksec->sclass = SECCLASS_TUN_SOCKET;
5582 
5583 	return 0;
5584 }
5585 
5586 static int selinux_tun_dev_open(void *security)
5587 {
5588 	struct tun_security_struct *tunsec = security;
5589 	u32 sid = current_sid();
5590 	int err;
5591 
5592 	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5593 			   TUN_SOCKET__RELABELFROM, NULL);
5594 	if (err)
5595 		return err;
5596 	err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5597 			   TUN_SOCKET__RELABELTO, NULL);
5598 	if (err)
5599 		return err;
5600 	tunsec->sid = sid;
5601 
5602 	return 0;
5603 }
5604 
5605 #ifdef CONFIG_NETFILTER
5606 
5607 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5608 				       const struct nf_hook_state *state)
5609 {
5610 	int ifindex;
5611 	u16 family;
5612 	char *addrp;
5613 	u32 peer_sid;
5614 	struct common_audit_data ad;
5615 	struct lsm_network_audit net = {0,};
5616 	int secmark_active, peerlbl_active;
5617 
5618 	if (!selinux_policycap_netpeer())
5619 		return NF_ACCEPT;
5620 
5621 	secmark_active = selinux_secmark_enabled();
5622 	peerlbl_active = selinux_peerlbl_enabled();
5623 	if (!secmark_active && !peerlbl_active)
5624 		return NF_ACCEPT;
5625 
5626 	family = state->pf;
5627 	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5628 		return NF_DROP;
5629 
5630 	ifindex = state->in->ifindex;
5631 	ad.type = LSM_AUDIT_DATA_NET;
5632 	ad.u.net = &net;
5633 	ad.u.net->netif = ifindex;
5634 	ad.u.net->family = family;
5635 	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5636 		return NF_DROP;
5637 
5638 	if (peerlbl_active) {
5639 		int err;
5640 
5641 		err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5642 					       addrp, family, peer_sid, &ad);
5643 		if (err) {
5644 			selinux_netlbl_err(skb, family, err, 1);
5645 			return NF_DROP;
5646 		}
5647 	}
5648 
5649 	if (secmark_active)
5650 		if (avc_has_perm(peer_sid, skb->secmark,
5651 				 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5652 			return NF_DROP;
5653 
5654 	if (netlbl_enabled())
5655 		/* we do this in the FORWARD path and not the POST_ROUTING
5656 		 * path because we want to make sure we apply the necessary
5657 		 * labeling before IPsec is applied so we can leverage AH
5658 		 * protection */
5659 		if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5660 			return NF_DROP;
5661 
5662 	return NF_ACCEPT;
5663 }
5664 
5665 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5666 				      const struct nf_hook_state *state)
5667 {
5668 	struct sock *sk;
5669 	u32 sid;
5670 
5671 	if (!netlbl_enabled())
5672 		return NF_ACCEPT;
5673 
5674 	/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5675 	 * because we want to make sure we apply the necessary labeling
5676 	 * before IPsec is applied so we can leverage AH protection */
5677 	sk = skb->sk;
5678 	if (sk) {
5679 		struct sk_security_struct *sksec;
5680 
5681 		if (sk_listener(sk))
5682 			/* if the socket is the listening state then this
5683 			 * packet is a SYN-ACK packet which means it needs to
5684 			 * be labeled based on the connection/request_sock and
5685 			 * not the parent socket.  unfortunately, we can't
5686 			 * lookup the request_sock yet as it isn't queued on
5687 			 * the parent socket until after the SYN-ACK is sent.
5688 			 * the "solution" is to simply pass the packet as-is
5689 			 * as any IP option based labeling should be copied
5690 			 * from the initial connection request (in the IP
5691 			 * layer).  it is far from ideal, but until we get a
5692 			 * security label in the packet itself this is the
5693 			 * best we can do. */
5694 			return NF_ACCEPT;
5695 
5696 		/* standard practice, label using the parent socket */
5697 		sksec = sk->sk_security;
5698 		sid = sksec->sid;
5699 	} else
5700 		sid = SECINITSID_KERNEL;
5701 	if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5702 		return NF_DROP;
5703 
5704 	return NF_ACCEPT;
5705 }
5706 
5707 
5708 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5709 					const struct nf_hook_state *state)
5710 {
5711 	struct sock *sk;
5712 	struct sk_security_struct *sksec;
5713 	struct common_audit_data ad;
5714 	struct lsm_network_audit net = {0,};
5715 	u8 proto = 0;
5716 
5717 	sk = skb_to_full_sk(skb);
5718 	if (sk == NULL)
5719 		return NF_ACCEPT;
5720 	sksec = sk->sk_security;
5721 
5722 	ad.type = LSM_AUDIT_DATA_NET;
5723 	ad.u.net = &net;
5724 	ad.u.net->netif = state->out->ifindex;
5725 	ad.u.net->family = state->pf;
5726 	if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5727 		return NF_DROP;
5728 
5729 	if (selinux_secmark_enabled())
5730 		if (avc_has_perm(sksec->sid, skb->secmark,
5731 				 SECCLASS_PACKET, PACKET__SEND, &ad))
5732 			return NF_DROP_ERR(-ECONNREFUSED);
5733 
5734 	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5735 		return NF_DROP_ERR(-ECONNREFUSED);
5736 
5737 	return NF_ACCEPT;
5738 }
5739 
5740 static unsigned int selinux_ip_postroute(void *priv,
5741 					 struct sk_buff *skb,
5742 					 const struct nf_hook_state *state)
5743 {
5744 	u16 family;
5745 	u32 secmark_perm;
5746 	u32 peer_sid;
5747 	int ifindex;
5748 	struct sock *sk;
5749 	struct common_audit_data ad;
5750 	struct lsm_network_audit net = {0,};
5751 	char *addrp;
5752 	int secmark_active, peerlbl_active;
5753 
5754 	/* If any sort of compatibility mode is enabled then handoff processing
5755 	 * to the selinux_ip_postroute_compat() function to deal with the
5756 	 * special handling.  We do this in an attempt to keep this function
5757 	 * as fast and as clean as possible. */
5758 	if (!selinux_policycap_netpeer())
5759 		return selinux_ip_postroute_compat(skb, state);
5760 
5761 	secmark_active = selinux_secmark_enabled();
5762 	peerlbl_active = selinux_peerlbl_enabled();
5763 	if (!secmark_active && !peerlbl_active)
5764 		return NF_ACCEPT;
5765 
5766 	sk = skb_to_full_sk(skb);
5767 
5768 #ifdef CONFIG_XFRM
5769 	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5770 	 * packet transformation so allow the packet to pass without any checks
5771 	 * since we'll have another chance to perform access control checks
5772 	 * when the packet is on it's final way out.
5773 	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5774 	 *       is NULL, in this case go ahead and apply access control.
5775 	 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5776 	 *       TCP listening state we cannot wait until the XFRM processing
5777 	 *       is done as we will miss out on the SA label if we do;
5778 	 *       unfortunately, this means more work, but it is only once per
5779 	 *       connection. */
5780 	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5781 	    !(sk && sk_listener(sk)))
5782 		return NF_ACCEPT;
5783 #endif
5784 
5785 	family = state->pf;
5786 	if (sk == NULL) {
5787 		/* Without an associated socket the packet is either coming
5788 		 * from the kernel or it is being forwarded; check the packet
5789 		 * to determine which and if the packet is being forwarded
5790 		 * query the packet directly to determine the security label. */
5791 		if (skb->skb_iif) {
5792 			secmark_perm = PACKET__FORWARD_OUT;
5793 			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5794 				return NF_DROP;
5795 		} else {
5796 			secmark_perm = PACKET__SEND;
5797 			peer_sid = SECINITSID_KERNEL;
5798 		}
5799 	} else if (sk_listener(sk)) {
5800 		/* Locally generated packet but the associated socket is in the
5801 		 * listening state which means this is a SYN-ACK packet.  In
5802 		 * this particular case the correct security label is assigned
5803 		 * to the connection/request_sock but unfortunately we can't
5804 		 * query the request_sock as it isn't queued on the parent
5805 		 * socket until after the SYN-ACK packet is sent; the only
5806 		 * viable choice is to regenerate the label like we do in
5807 		 * selinux_inet_conn_request().  See also selinux_ip_output()
5808 		 * for similar problems. */
5809 		u32 skb_sid;
5810 		struct sk_security_struct *sksec;
5811 
5812 		sksec = sk->sk_security;
5813 		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5814 			return NF_DROP;
5815 		/* At this point, if the returned skb peerlbl is SECSID_NULL
5816 		 * and the packet has been through at least one XFRM
5817 		 * transformation then we must be dealing with the "final"
5818 		 * form of labeled IPsec packet; since we've already applied
5819 		 * all of our access controls on this packet we can safely
5820 		 * pass the packet. */
5821 		if (skb_sid == SECSID_NULL) {
5822 			switch (family) {
5823 			case PF_INET:
5824 				if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5825 					return NF_ACCEPT;
5826 				break;
5827 			case PF_INET6:
5828 				if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5829 					return NF_ACCEPT;
5830 				break;
5831 			default:
5832 				return NF_DROP_ERR(-ECONNREFUSED);
5833 			}
5834 		}
5835 		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5836 			return NF_DROP;
5837 		secmark_perm = PACKET__SEND;
5838 	} else {
5839 		/* Locally generated packet, fetch the security label from the
5840 		 * associated socket. */
5841 		struct sk_security_struct *sksec = sk->sk_security;
5842 		peer_sid = sksec->sid;
5843 		secmark_perm = PACKET__SEND;
5844 	}
5845 
5846 	ifindex = state->out->ifindex;
5847 	ad.type = LSM_AUDIT_DATA_NET;
5848 	ad.u.net = &net;
5849 	ad.u.net->netif = ifindex;
5850 	ad.u.net->family = family;
5851 	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5852 		return NF_DROP;
5853 
5854 	if (secmark_active)
5855 		if (avc_has_perm(peer_sid, skb->secmark,
5856 				 SECCLASS_PACKET, secmark_perm, &ad))
5857 			return NF_DROP_ERR(-ECONNREFUSED);
5858 
5859 	if (peerlbl_active) {
5860 		u32 if_sid;
5861 		u32 node_sid;
5862 
5863 		if (sel_netif_sid(state->net, ifindex, &if_sid))
5864 			return NF_DROP;
5865 		if (avc_has_perm(peer_sid, if_sid,
5866 				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5867 			return NF_DROP_ERR(-ECONNREFUSED);
5868 
5869 		if (sel_netnode_sid(addrp, family, &node_sid))
5870 			return NF_DROP;
5871 		if (avc_has_perm(peer_sid, node_sid,
5872 				 SECCLASS_NODE, NODE__SENDTO, &ad))
5873 			return NF_DROP_ERR(-ECONNREFUSED);
5874 	}
5875 
5876 	return NF_ACCEPT;
5877 }
5878 #endif	/* CONFIG_NETFILTER */
5879 
5880 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5881 {
5882 	int rc = 0;
5883 	unsigned int msg_len;
5884 	unsigned int data_len = skb->len;
5885 	unsigned char *data = skb->data;
5886 	struct nlmsghdr *nlh;
5887 	struct sk_security_struct *sksec = sk->sk_security;
5888 	u16 sclass = sksec->sclass;
5889 	u32 perm;
5890 
5891 	while (data_len >= nlmsg_total_size(0)) {
5892 		nlh = (struct nlmsghdr *)data;
5893 
5894 		/* NOTE: the nlmsg_len field isn't reliably set by some netlink
5895 		 *       users which means we can't reject skb's with bogus
5896 		 *       length fields; our solution is to follow what
5897 		 *       netlink_rcv_skb() does and simply skip processing at
5898 		 *       messages with length fields that are clearly junk
5899 		 */
5900 		if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5901 			return 0;
5902 
5903 		rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5904 		if (rc == 0) {
5905 			rc = sock_has_perm(sk, perm);
5906 			if (rc)
5907 				return rc;
5908 		} else if (rc == -EINVAL) {
5909 			/* -EINVAL is a missing msg/perm mapping */
5910 			pr_warn_ratelimited("SELinux: unrecognized netlink"
5911 				" message: protocol=%hu nlmsg_type=%hu sclass=%s"
5912 				" pid=%d comm=%s\n",
5913 				sk->sk_protocol, nlh->nlmsg_type,
5914 				secclass_map[sclass - 1].name,
5915 				task_pid_nr(current), current->comm);
5916 			if (enforcing_enabled() &&
5917 			    !security_get_allow_unknown())
5918 				return rc;
5919 			rc = 0;
5920 		} else if (rc == -ENOENT) {
5921 			/* -ENOENT is a missing socket/class mapping, ignore */
5922 			rc = 0;
5923 		} else {
5924 			return rc;
5925 		}
5926 
5927 		/* move to the next message after applying netlink padding */
5928 		msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
5929 		if (msg_len >= data_len)
5930 			return 0;
5931 		data_len -= msg_len;
5932 		data += msg_len;
5933 	}
5934 
5935 	return rc;
5936 }
5937 
5938 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5939 {
5940 	isec->sclass = sclass;
5941 	isec->sid = current_sid();
5942 }
5943 
5944 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5945 			u32 perms)
5946 {
5947 	struct ipc_security_struct *isec;
5948 	struct common_audit_data ad;
5949 	u32 sid = current_sid();
5950 
5951 	isec = selinux_ipc(ipc_perms);
5952 
5953 	ad.type = LSM_AUDIT_DATA_IPC;
5954 	ad.u.ipc_id = ipc_perms->key;
5955 
5956 	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5957 }
5958 
5959 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5960 {
5961 	struct msg_security_struct *msec;
5962 
5963 	msec = selinux_msg_msg(msg);
5964 	msec->sid = SECINITSID_UNLABELED;
5965 
5966 	return 0;
5967 }
5968 
5969 /* message queue security operations */
5970 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5971 {
5972 	struct ipc_security_struct *isec;
5973 	struct common_audit_data ad;
5974 	u32 sid = current_sid();
5975 
5976 	isec = selinux_ipc(msq);
5977 	ipc_init_security(isec, SECCLASS_MSGQ);
5978 
5979 	ad.type = LSM_AUDIT_DATA_IPC;
5980 	ad.u.ipc_id = msq->key;
5981 
5982 	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5983 			    MSGQ__CREATE, &ad);
5984 }
5985 
5986 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
5987 {
5988 	struct ipc_security_struct *isec;
5989 	struct common_audit_data ad;
5990 	u32 sid = current_sid();
5991 
5992 	isec = selinux_ipc(msq);
5993 
5994 	ad.type = LSM_AUDIT_DATA_IPC;
5995 	ad.u.ipc_id = msq->key;
5996 
5997 	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5998 			    MSGQ__ASSOCIATE, &ad);
5999 }
6000 
6001 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6002 {
6003 	int err;
6004 	int perms;
6005 
6006 	switch (cmd) {
6007 	case IPC_INFO:
6008 	case MSG_INFO:
6009 		/* No specific object, just general system-wide information. */
6010 		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6011 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6012 	case IPC_STAT:
6013 	case MSG_STAT:
6014 	case MSG_STAT_ANY:
6015 		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6016 		break;
6017 	case IPC_SET:
6018 		perms = MSGQ__SETATTR;
6019 		break;
6020 	case IPC_RMID:
6021 		perms = MSGQ__DESTROY;
6022 		break;
6023 	default:
6024 		return 0;
6025 	}
6026 
6027 	err = ipc_has_perm(msq, perms);
6028 	return err;
6029 }
6030 
6031 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6032 {
6033 	struct ipc_security_struct *isec;
6034 	struct msg_security_struct *msec;
6035 	struct common_audit_data ad;
6036 	u32 sid = current_sid();
6037 	int rc;
6038 
6039 	isec = selinux_ipc(msq);
6040 	msec = selinux_msg_msg(msg);
6041 
6042 	/*
6043 	 * First time through, need to assign label to the message
6044 	 */
6045 	if (msec->sid == SECINITSID_UNLABELED) {
6046 		/*
6047 		 * Compute new sid based on current process and
6048 		 * message queue this message will be stored in
6049 		 */
6050 		rc = security_transition_sid(sid, isec->sid,
6051 					     SECCLASS_MSG, NULL, &msec->sid);
6052 		if (rc)
6053 			return rc;
6054 	}
6055 
6056 	ad.type = LSM_AUDIT_DATA_IPC;
6057 	ad.u.ipc_id = msq->key;
6058 
6059 	/* Can this process write to the queue? */
6060 	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6061 			  MSGQ__WRITE, &ad);
6062 	if (!rc)
6063 		/* Can this process send the message */
6064 		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
6065 				  MSG__SEND, &ad);
6066 	if (!rc)
6067 		/* Can the message be put in the queue? */
6068 		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
6069 				  MSGQ__ENQUEUE, &ad);
6070 
6071 	return rc;
6072 }
6073 
6074 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6075 				    struct task_struct *target,
6076 				    long type, int mode)
6077 {
6078 	struct ipc_security_struct *isec;
6079 	struct msg_security_struct *msec;
6080 	struct common_audit_data ad;
6081 	u32 sid = task_sid_obj(target);
6082 	int rc;
6083 
6084 	isec = selinux_ipc(msq);
6085 	msec = selinux_msg_msg(msg);
6086 
6087 	ad.type = LSM_AUDIT_DATA_IPC;
6088 	ad.u.ipc_id = msq->key;
6089 
6090 	rc = avc_has_perm(sid, isec->sid,
6091 			  SECCLASS_MSGQ, MSGQ__READ, &ad);
6092 	if (!rc)
6093 		rc = avc_has_perm(sid, msec->sid,
6094 				  SECCLASS_MSG, MSG__RECEIVE, &ad);
6095 	return rc;
6096 }
6097 
6098 /* Shared Memory security operations */
6099 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6100 {
6101 	struct ipc_security_struct *isec;
6102 	struct common_audit_data ad;
6103 	u32 sid = current_sid();
6104 
6105 	isec = selinux_ipc(shp);
6106 	ipc_init_security(isec, SECCLASS_SHM);
6107 
6108 	ad.type = LSM_AUDIT_DATA_IPC;
6109 	ad.u.ipc_id = shp->key;
6110 
6111 	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6112 			    SHM__CREATE, &ad);
6113 }
6114 
6115 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6116 {
6117 	struct ipc_security_struct *isec;
6118 	struct common_audit_data ad;
6119 	u32 sid = current_sid();
6120 
6121 	isec = selinux_ipc(shp);
6122 
6123 	ad.type = LSM_AUDIT_DATA_IPC;
6124 	ad.u.ipc_id = shp->key;
6125 
6126 	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6127 			    SHM__ASSOCIATE, &ad);
6128 }
6129 
6130 /* Note, at this point, shp is locked down */
6131 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6132 {
6133 	int perms;
6134 	int err;
6135 
6136 	switch (cmd) {
6137 	case IPC_INFO:
6138 	case SHM_INFO:
6139 		/* No specific object, just general system-wide information. */
6140 		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6141 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6142 	case IPC_STAT:
6143 	case SHM_STAT:
6144 	case SHM_STAT_ANY:
6145 		perms = SHM__GETATTR | SHM__ASSOCIATE;
6146 		break;
6147 	case IPC_SET:
6148 		perms = SHM__SETATTR;
6149 		break;
6150 	case SHM_LOCK:
6151 	case SHM_UNLOCK:
6152 		perms = SHM__LOCK;
6153 		break;
6154 	case IPC_RMID:
6155 		perms = SHM__DESTROY;
6156 		break;
6157 	default:
6158 		return 0;
6159 	}
6160 
6161 	err = ipc_has_perm(shp, perms);
6162 	return err;
6163 }
6164 
6165 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6166 			     char __user *shmaddr, int shmflg)
6167 {
6168 	u32 perms;
6169 
6170 	if (shmflg & SHM_RDONLY)
6171 		perms = SHM__READ;
6172 	else
6173 		perms = SHM__READ | SHM__WRITE;
6174 
6175 	return ipc_has_perm(shp, perms);
6176 }
6177 
6178 /* Semaphore security operations */
6179 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6180 {
6181 	struct ipc_security_struct *isec;
6182 	struct common_audit_data ad;
6183 	u32 sid = current_sid();
6184 
6185 	isec = selinux_ipc(sma);
6186 	ipc_init_security(isec, SECCLASS_SEM);
6187 
6188 	ad.type = LSM_AUDIT_DATA_IPC;
6189 	ad.u.ipc_id = sma->key;
6190 
6191 	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6192 			    SEM__CREATE, &ad);
6193 }
6194 
6195 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6196 {
6197 	struct ipc_security_struct *isec;
6198 	struct common_audit_data ad;
6199 	u32 sid = current_sid();
6200 
6201 	isec = selinux_ipc(sma);
6202 
6203 	ad.type = LSM_AUDIT_DATA_IPC;
6204 	ad.u.ipc_id = sma->key;
6205 
6206 	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6207 			    SEM__ASSOCIATE, &ad);
6208 }
6209 
6210 /* Note, at this point, sma is locked down */
6211 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6212 {
6213 	int err;
6214 	u32 perms;
6215 
6216 	switch (cmd) {
6217 	case IPC_INFO:
6218 	case SEM_INFO:
6219 		/* No specific object, just general system-wide information. */
6220 		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6221 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6222 	case GETPID:
6223 	case GETNCNT:
6224 	case GETZCNT:
6225 		perms = SEM__GETATTR;
6226 		break;
6227 	case GETVAL:
6228 	case GETALL:
6229 		perms = SEM__READ;
6230 		break;
6231 	case SETVAL:
6232 	case SETALL:
6233 		perms = SEM__WRITE;
6234 		break;
6235 	case IPC_RMID:
6236 		perms = SEM__DESTROY;
6237 		break;
6238 	case IPC_SET:
6239 		perms = SEM__SETATTR;
6240 		break;
6241 	case IPC_STAT:
6242 	case SEM_STAT:
6243 	case SEM_STAT_ANY:
6244 		perms = SEM__GETATTR | SEM__ASSOCIATE;
6245 		break;
6246 	default:
6247 		return 0;
6248 	}
6249 
6250 	err = ipc_has_perm(sma, perms);
6251 	return err;
6252 }
6253 
6254 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6255 			     struct sembuf *sops, unsigned nsops, int alter)
6256 {
6257 	u32 perms;
6258 
6259 	if (alter)
6260 		perms = SEM__READ | SEM__WRITE;
6261 	else
6262 		perms = SEM__READ;
6263 
6264 	return ipc_has_perm(sma, perms);
6265 }
6266 
6267 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6268 {
6269 	u32 av = 0;
6270 
6271 	av = 0;
6272 	if (flag & S_IRUGO)
6273 		av |= IPC__UNIX_READ;
6274 	if (flag & S_IWUGO)
6275 		av |= IPC__UNIX_WRITE;
6276 
6277 	if (av == 0)
6278 		return 0;
6279 
6280 	return ipc_has_perm(ipcp, av);
6281 }
6282 
6283 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6284 {
6285 	struct ipc_security_struct *isec = selinux_ipc(ipcp);
6286 	*secid = isec->sid;
6287 }
6288 
6289 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6290 {
6291 	if (inode)
6292 		inode_doinit_with_dentry(inode, dentry);
6293 }
6294 
6295 static int selinux_getprocattr(struct task_struct *p,
6296 			       const char *name, char **value)
6297 {
6298 	const struct task_security_struct *__tsec;
6299 	u32 sid;
6300 	int error;
6301 	unsigned len;
6302 
6303 	rcu_read_lock();
6304 	__tsec = selinux_cred(__task_cred(p));
6305 
6306 	if (current != p) {
6307 		error = avc_has_perm(current_sid(), __tsec->sid,
6308 				     SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6309 		if (error)
6310 			goto bad;
6311 	}
6312 
6313 	if (!strcmp(name, "current"))
6314 		sid = __tsec->sid;
6315 	else if (!strcmp(name, "prev"))
6316 		sid = __tsec->osid;
6317 	else if (!strcmp(name, "exec"))
6318 		sid = __tsec->exec_sid;
6319 	else if (!strcmp(name, "fscreate"))
6320 		sid = __tsec->create_sid;
6321 	else if (!strcmp(name, "keycreate"))
6322 		sid = __tsec->keycreate_sid;
6323 	else if (!strcmp(name, "sockcreate"))
6324 		sid = __tsec->sockcreate_sid;
6325 	else {
6326 		error = -EINVAL;
6327 		goto bad;
6328 	}
6329 	rcu_read_unlock();
6330 
6331 	if (!sid)
6332 		return 0;
6333 
6334 	error = security_sid_to_context(sid, value, &len);
6335 	if (error)
6336 		return error;
6337 	return len;
6338 
6339 bad:
6340 	rcu_read_unlock();
6341 	return error;
6342 }
6343 
6344 static int selinux_setprocattr(const char *name, void *value, size_t size)
6345 {
6346 	struct task_security_struct *tsec;
6347 	struct cred *new;
6348 	u32 mysid = current_sid(), sid = 0, ptsid;
6349 	int error;
6350 	char *str = value;
6351 
6352 	/*
6353 	 * Basic control over ability to set these attributes at all.
6354 	 */
6355 	if (!strcmp(name, "exec"))
6356 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6357 				     PROCESS__SETEXEC, NULL);
6358 	else if (!strcmp(name, "fscreate"))
6359 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6360 				     PROCESS__SETFSCREATE, NULL);
6361 	else if (!strcmp(name, "keycreate"))
6362 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6363 				     PROCESS__SETKEYCREATE, NULL);
6364 	else if (!strcmp(name, "sockcreate"))
6365 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6366 				     PROCESS__SETSOCKCREATE, NULL);
6367 	else if (!strcmp(name, "current"))
6368 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6369 				     PROCESS__SETCURRENT, NULL);
6370 	else
6371 		error = -EINVAL;
6372 	if (error)
6373 		return error;
6374 
6375 	/* Obtain a SID for the context, if one was specified. */
6376 	if (size && str[0] && str[0] != '\n') {
6377 		if (str[size-1] == '\n') {
6378 			str[size-1] = 0;
6379 			size--;
6380 		}
6381 		error = security_context_to_sid(value, size,
6382 						&sid, GFP_KERNEL);
6383 		if (error == -EINVAL && !strcmp(name, "fscreate")) {
6384 			if (!has_cap_mac_admin(true)) {
6385 				struct audit_buffer *ab;
6386 				size_t audit_size;
6387 
6388 				/* We strip a nul only if it is at the end, otherwise the
6389 				 * context contains a nul and we should audit that */
6390 				if (str[size - 1] == '\0')
6391 					audit_size = size - 1;
6392 				else
6393 					audit_size = size;
6394 				ab = audit_log_start(audit_context(),
6395 						     GFP_ATOMIC,
6396 						     AUDIT_SELINUX_ERR);
6397 				if (!ab)
6398 					return error;
6399 				audit_log_format(ab, "op=fscreate invalid_context=");
6400 				audit_log_n_untrustedstring(ab, value, audit_size);
6401 				audit_log_end(ab);
6402 
6403 				return error;
6404 			}
6405 			error = security_context_to_sid_force(value, size,
6406 							&sid);
6407 		}
6408 		if (error)
6409 			return error;
6410 	}
6411 
6412 	new = prepare_creds();
6413 	if (!new)
6414 		return -ENOMEM;
6415 
6416 	/* Permission checking based on the specified context is
6417 	   performed during the actual operation (execve,
6418 	   open/mkdir/...), when we know the full context of the
6419 	   operation.  See selinux_bprm_creds_for_exec for the execve
6420 	   checks and may_create for the file creation checks. The
6421 	   operation will then fail if the context is not permitted. */
6422 	tsec = selinux_cred(new);
6423 	if (!strcmp(name, "exec")) {
6424 		tsec->exec_sid = sid;
6425 	} else if (!strcmp(name, "fscreate")) {
6426 		tsec->create_sid = sid;
6427 	} else if (!strcmp(name, "keycreate")) {
6428 		if (sid) {
6429 			error = avc_has_perm(mysid, sid,
6430 					     SECCLASS_KEY, KEY__CREATE, NULL);
6431 			if (error)
6432 				goto abort_change;
6433 		}
6434 		tsec->keycreate_sid = sid;
6435 	} else if (!strcmp(name, "sockcreate")) {
6436 		tsec->sockcreate_sid = sid;
6437 	} else if (!strcmp(name, "current")) {
6438 		error = -EINVAL;
6439 		if (sid == 0)
6440 			goto abort_change;
6441 
6442 		/* Only allow single threaded processes to change context */
6443 		if (!current_is_single_threaded()) {
6444 			error = security_bounded_transition(tsec->sid, sid);
6445 			if (error)
6446 				goto abort_change;
6447 		}
6448 
6449 		/* Check permissions for the transition. */
6450 		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6451 				     PROCESS__DYNTRANSITION, NULL);
6452 		if (error)
6453 			goto abort_change;
6454 
6455 		/* Check for ptracing, and update the task SID if ok.
6456 		   Otherwise, leave SID unchanged and fail. */
6457 		ptsid = ptrace_parent_sid();
6458 		if (ptsid != 0) {
6459 			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
6460 					     PROCESS__PTRACE, NULL);
6461 			if (error)
6462 				goto abort_change;
6463 		}
6464 
6465 		tsec->sid = sid;
6466 	} else {
6467 		error = -EINVAL;
6468 		goto abort_change;
6469 	}
6470 
6471 	commit_creds(new);
6472 	return size;
6473 
6474 abort_change:
6475 	abort_creds(new);
6476 	return error;
6477 }
6478 
6479 static int selinux_ismaclabel(const char *name)
6480 {
6481 	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6482 }
6483 
6484 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6485 {
6486 	return security_sid_to_context(secid,
6487 				       secdata, seclen);
6488 }
6489 
6490 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6491 {
6492 	return security_context_to_sid(secdata, seclen,
6493 				       secid, GFP_KERNEL);
6494 }
6495 
6496 static void selinux_release_secctx(char *secdata, u32 seclen)
6497 {
6498 	kfree(secdata);
6499 }
6500 
6501 static void selinux_inode_invalidate_secctx(struct inode *inode)
6502 {
6503 	struct inode_security_struct *isec = selinux_inode(inode);
6504 
6505 	spin_lock(&isec->lock);
6506 	isec->initialized = LABEL_INVALID;
6507 	spin_unlock(&isec->lock);
6508 }
6509 
6510 /*
6511  *	called with inode->i_mutex locked
6512  */
6513 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6514 {
6515 	int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6516 					   ctx, ctxlen, 0);
6517 	/* Do not return error when suppressing label (SBLABEL_MNT not set). */
6518 	return rc == -EOPNOTSUPP ? 0 : rc;
6519 }
6520 
6521 /*
6522  *	called with inode->i_mutex locked
6523  */
6524 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6525 {
6526 	return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6527 				     ctx, ctxlen, 0);
6528 }
6529 
6530 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6531 {
6532 	int len = 0;
6533 	len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6534 					XATTR_SELINUX_SUFFIX, ctx, true);
6535 	if (len < 0)
6536 		return len;
6537 	*ctxlen = len;
6538 	return 0;
6539 }
6540 #ifdef CONFIG_KEYS
6541 
6542 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6543 			     unsigned long flags)
6544 {
6545 	const struct task_security_struct *tsec;
6546 	struct key_security_struct *ksec;
6547 
6548 	ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6549 	if (!ksec)
6550 		return -ENOMEM;
6551 
6552 	tsec = selinux_cred(cred);
6553 	if (tsec->keycreate_sid)
6554 		ksec->sid = tsec->keycreate_sid;
6555 	else
6556 		ksec->sid = tsec->sid;
6557 
6558 	k->security = ksec;
6559 	return 0;
6560 }
6561 
6562 static void selinux_key_free(struct key *k)
6563 {
6564 	struct key_security_struct *ksec = k->security;
6565 
6566 	k->security = NULL;
6567 	kfree(ksec);
6568 }
6569 
6570 static int selinux_key_permission(key_ref_t key_ref,
6571 				  const struct cred *cred,
6572 				  enum key_need_perm need_perm)
6573 {
6574 	struct key *key;
6575 	struct key_security_struct *ksec;
6576 	u32 perm, sid;
6577 
6578 	switch (need_perm) {
6579 	case KEY_NEED_VIEW:
6580 		perm = KEY__VIEW;
6581 		break;
6582 	case KEY_NEED_READ:
6583 		perm = KEY__READ;
6584 		break;
6585 	case KEY_NEED_WRITE:
6586 		perm = KEY__WRITE;
6587 		break;
6588 	case KEY_NEED_SEARCH:
6589 		perm = KEY__SEARCH;
6590 		break;
6591 	case KEY_NEED_LINK:
6592 		perm = KEY__LINK;
6593 		break;
6594 	case KEY_NEED_SETATTR:
6595 		perm = KEY__SETATTR;
6596 		break;
6597 	case KEY_NEED_UNLINK:
6598 	case KEY_SYSADMIN_OVERRIDE:
6599 	case KEY_AUTHTOKEN_OVERRIDE:
6600 	case KEY_DEFER_PERM_CHECK:
6601 		return 0;
6602 	default:
6603 		WARN_ON(1);
6604 		return -EPERM;
6605 
6606 	}
6607 
6608 	sid = cred_sid(cred);
6609 	key = key_ref_to_ptr(key_ref);
6610 	ksec = key->security;
6611 
6612 	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6613 }
6614 
6615 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6616 {
6617 	struct key_security_struct *ksec = key->security;
6618 	char *context = NULL;
6619 	unsigned len;
6620 	int rc;
6621 
6622 	rc = security_sid_to_context(ksec->sid,
6623 				     &context, &len);
6624 	if (!rc)
6625 		rc = len;
6626 	*_buffer = context;
6627 	return rc;
6628 }
6629 
6630 #ifdef CONFIG_KEY_NOTIFICATIONS
6631 static int selinux_watch_key(struct key *key)
6632 {
6633 	struct key_security_struct *ksec = key->security;
6634 	u32 sid = current_sid();
6635 
6636 	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6637 }
6638 #endif
6639 #endif
6640 
6641 #ifdef CONFIG_SECURITY_INFINIBAND
6642 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6643 {
6644 	struct common_audit_data ad;
6645 	int err;
6646 	u32 sid = 0;
6647 	struct ib_security_struct *sec = ib_sec;
6648 	struct lsm_ibpkey_audit ibpkey;
6649 
6650 	err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6651 	if (err)
6652 		return err;
6653 
6654 	ad.type = LSM_AUDIT_DATA_IBPKEY;
6655 	ibpkey.subnet_prefix = subnet_prefix;
6656 	ibpkey.pkey = pkey_val;
6657 	ad.u.ibpkey = &ibpkey;
6658 	return avc_has_perm(sec->sid, sid,
6659 			    SECCLASS_INFINIBAND_PKEY,
6660 			    INFINIBAND_PKEY__ACCESS, &ad);
6661 }
6662 
6663 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6664 					    u8 port_num)
6665 {
6666 	struct common_audit_data ad;
6667 	int err;
6668 	u32 sid = 0;
6669 	struct ib_security_struct *sec = ib_sec;
6670 	struct lsm_ibendport_audit ibendport;
6671 
6672 	err = security_ib_endport_sid(dev_name, port_num,
6673 				      &sid);
6674 
6675 	if (err)
6676 		return err;
6677 
6678 	ad.type = LSM_AUDIT_DATA_IBENDPORT;
6679 	ibendport.dev_name = dev_name;
6680 	ibendport.port = port_num;
6681 	ad.u.ibendport = &ibendport;
6682 	return avc_has_perm(sec->sid, sid,
6683 			    SECCLASS_INFINIBAND_ENDPORT,
6684 			    INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6685 }
6686 
6687 static int selinux_ib_alloc_security(void **ib_sec)
6688 {
6689 	struct ib_security_struct *sec;
6690 
6691 	sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6692 	if (!sec)
6693 		return -ENOMEM;
6694 	sec->sid = current_sid();
6695 
6696 	*ib_sec = sec;
6697 	return 0;
6698 }
6699 
6700 static void selinux_ib_free_security(void *ib_sec)
6701 {
6702 	kfree(ib_sec);
6703 }
6704 #endif
6705 
6706 #ifdef CONFIG_BPF_SYSCALL
6707 static int selinux_bpf(int cmd, union bpf_attr *attr,
6708 				     unsigned int size)
6709 {
6710 	u32 sid = current_sid();
6711 	int ret;
6712 
6713 	switch (cmd) {
6714 	case BPF_MAP_CREATE:
6715 		ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6716 				   NULL);
6717 		break;
6718 	case BPF_PROG_LOAD:
6719 		ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6720 				   NULL);
6721 		break;
6722 	default:
6723 		ret = 0;
6724 		break;
6725 	}
6726 
6727 	return ret;
6728 }
6729 
6730 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6731 {
6732 	u32 av = 0;
6733 
6734 	if (fmode & FMODE_READ)
6735 		av |= BPF__MAP_READ;
6736 	if (fmode & FMODE_WRITE)
6737 		av |= BPF__MAP_WRITE;
6738 	return av;
6739 }
6740 
6741 /* This function will check the file pass through unix socket or binder to see
6742  * if it is a bpf related object. And apply corresponding checks on the bpf
6743  * object based on the type. The bpf maps and programs, not like other files and
6744  * socket, are using a shared anonymous inode inside the kernel as their inode.
6745  * So checking that inode cannot identify if the process have privilege to
6746  * access the bpf object and that's why we have to add this additional check in
6747  * selinux_file_receive and selinux_binder_transfer_files.
6748  */
6749 static int bpf_fd_pass(struct file *file, u32 sid)
6750 {
6751 	struct bpf_security_struct *bpfsec;
6752 	struct bpf_prog *prog;
6753 	struct bpf_map *map;
6754 	int ret;
6755 
6756 	if (file->f_op == &bpf_map_fops) {
6757 		map = file->private_data;
6758 		bpfsec = map->security;
6759 		ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6760 				   bpf_map_fmode_to_av(file->f_mode), NULL);
6761 		if (ret)
6762 			return ret;
6763 	} else if (file->f_op == &bpf_prog_fops) {
6764 		prog = file->private_data;
6765 		bpfsec = prog->aux->security;
6766 		ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6767 				   BPF__PROG_RUN, NULL);
6768 		if (ret)
6769 			return ret;
6770 	}
6771 	return 0;
6772 }
6773 
6774 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6775 {
6776 	u32 sid = current_sid();
6777 	struct bpf_security_struct *bpfsec;
6778 
6779 	bpfsec = map->security;
6780 	return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6781 			    bpf_map_fmode_to_av(fmode), NULL);
6782 }
6783 
6784 static int selinux_bpf_prog(struct bpf_prog *prog)
6785 {
6786 	u32 sid = current_sid();
6787 	struct bpf_security_struct *bpfsec;
6788 
6789 	bpfsec = prog->aux->security;
6790 	return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6791 			    BPF__PROG_RUN, NULL);
6792 }
6793 
6794 static int selinux_bpf_map_alloc(struct bpf_map *map)
6795 {
6796 	struct bpf_security_struct *bpfsec;
6797 
6798 	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6799 	if (!bpfsec)
6800 		return -ENOMEM;
6801 
6802 	bpfsec->sid = current_sid();
6803 	map->security = bpfsec;
6804 
6805 	return 0;
6806 }
6807 
6808 static void selinux_bpf_map_free(struct bpf_map *map)
6809 {
6810 	struct bpf_security_struct *bpfsec = map->security;
6811 
6812 	map->security = NULL;
6813 	kfree(bpfsec);
6814 }
6815 
6816 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6817 {
6818 	struct bpf_security_struct *bpfsec;
6819 
6820 	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6821 	if (!bpfsec)
6822 		return -ENOMEM;
6823 
6824 	bpfsec->sid = current_sid();
6825 	aux->security = bpfsec;
6826 
6827 	return 0;
6828 }
6829 
6830 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6831 {
6832 	struct bpf_security_struct *bpfsec = aux->security;
6833 
6834 	aux->security = NULL;
6835 	kfree(bpfsec);
6836 }
6837 #endif
6838 
6839 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
6840 	.lbs_cred = sizeof(struct task_security_struct),
6841 	.lbs_file = sizeof(struct file_security_struct),
6842 	.lbs_inode = sizeof(struct inode_security_struct),
6843 	.lbs_ipc = sizeof(struct ipc_security_struct),
6844 	.lbs_msg_msg = sizeof(struct msg_security_struct),
6845 	.lbs_superblock = sizeof(struct superblock_security_struct),
6846 };
6847 
6848 #ifdef CONFIG_PERF_EVENTS
6849 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
6850 {
6851 	u32 requested, sid = current_sid();
6852 
6853 	if (type == PERF_SECURITY_OPEN)
6854 		requested = PERF_EVENT__OPEN;
6855 	else if (type == PERF_SECURITY_CPU)
6856 		requested = PERF_EVENT__CPU;
6857 	else if (type == PERF_SECURITY_KERNEL)
6858 		requested = PERF_EVENT__KERNEL;
6859 	else if (type == PERF_SECURITY_TRACEPOINT)
6860 		requested = PERF_EVENT__TRACEPOINT;
6861 	else
6862 		return -EINVAL;
6863 
6864 	return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
6865 			    requested, NULL);
6866 }
6867 
6868 static int selinux_perf_event_alloc(struct perf_event *event)
6869 {
6870 	struct perf_event_security_struct *perfsec;
6871 
6872 	perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
6873 	if (!perfsec)
6874 		return -ENOMEM;
6875 
6876 	perfsec->sid = current_sid();
6877 	event->security = perfsec;
6878 
6879 	return 0;
6880 }
6881 
6882 static void selinux_perf_event_free(struct perf_event *event)
6883 {
6884 	struct perf_event_security_struct *perfsec = event->security;
6885 
6886 	event->security = NULL;
6887 	kfree(perfsec);
6888 }
6889 
6890 static int selinux_perf_event_read(struct perf_event *event)
6891 {
6892 	struct perf_event_security_struct *perfsec = event->security;
6893 	u32 sid = current_sid();
6894 
6895 	return avc_has_perm(sid, perfsec->sid,
6896 			    SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
6897 }
6898 
6899 static int selinux_perf_event_write(struct perf_event *event)
6900 {
6901 	struct perf_event_security_struct *perfsec = event->security;
6902 	u32 sid = current_sid();
6903 
6904 	return avc_has_perm(sid, perfsec->sid,
6905 			    SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
6906 }
6907 #endif
6908 
6909 #ifdef CONFIG_IO_URING
6910 /**
6911  * selinux_uring_override_creds - check the requested cred override
6912  * @new: the target creds
6913  *
6914  * Check to see if the current task is allowed to override it's credentials
6915  * to service an io_uring operation.
6916  */
6917 static int selinux_uring_override_creds(const struct cred *new)
6918 {
6919 	return avc_has_perm(current_sid(), cred_sid(new),
6920 			    SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
6921 }
6922 
6923 /**
6924  * selinux_uring_sqpoll - check if a io_uring polling thread can be created
6925  *
6926  * Check to see if the current task is allowed to create a new io_uring
6927  * kernel polling thread.
6928  */
6929 static int selinux_uring_sqpoll(void)
6930 {
6931 	int sid = current_sid();
6932 
6933 	return avc_has_perm(sid, sid,
6934 			    SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
6935 }
6936 
6937 /**
6938  * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
6939  * @ioucmd: the io_uring command structure
6940  *
6941  * Check to see if the current domain is allowed to execute an
6942  * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
6943  *
6944  */
6945 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
6946 {
6947 	struct file *file = ioucmd->file;
6948 	struct inode *inode = file_inode(file);
6949 	struct inode_security_struct *isec = selinux_inode(inode);
6950 	struct common_audit_data ad;
6951 
6952 	ad.type = LSM_AUDIT_DATA_FILE;
6953 	ad.u.file = file;
6954 
6955 	return avc_has_perm(current_sid(), isec->sid,
6956 			    SECCLASS_IO_URING, IO_URING__CMD, &ad);
6957 }
6958 #endif /* CONFIG_IO_URING */
6959 
6960 /*
6961  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
6962  * 1. any hooks that don't belong to (2.) or (3.) below,
6963  * 2. hooks that both access structures allocated by other hooks, and allocate
6964  *    structures that can be later accessed by other hooks (mostly "cloning"
6965  *    hooks),
6966  * 3. hooks that only allocate structures that can be later accessed by other
6967  *    hooks ("allocating" hooks).
6968  *
6969  * Please follow block comment delimiters in the list to keep this order.
6970  *
6971  * This ordering is needed for SELinux runtime disable to work at least somewhat
6972  * safely. Breaking the ordering rules above might lead to NULL pointer derefs
6973  * when disabling SELinux at runtime.
6974  */
6975 static struct security_hook_list selinux_hooks[] __ro_after_init = {
6976 	LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6977 	LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6978 	LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6979 	LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6980 
6981 	LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6982 	LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6983 	LSM_HOOK_INIT(capget, selinux_capget),
6984 	LSM_HOOK_INIT(capset, selinux_capset),
6985 	LSM_HOOK_INIT(capable, selinux_capable),
6986 	LSM_HOOK_INIT(quotactl, selinux_quotactl),
6987 	LSM_HOOK_INIT(quota_on, selinux_quota_on),
6988 	LSM_HOOK_INIT(syslog, selinux_syslog),
6989 	LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6990 
6991 	LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6992 
6993 	LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
6994 	LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6995 	LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6996 
6997 	LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
6998 	LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
6999 	LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7000 	LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7001 	LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7002 	LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7003 	LSM_HOOK_INIT(sb_mount, selinux_mount),
7004 	LSM_HOOK_INIT(sb_umount, selinux_umount),
7005 	LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7006 	LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7007 
7008 	LSM_HOOK_INIT(move_mount, selinux_move_mount),
7009 
7010 	LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7011 	LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7012 
7013 	LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7014 	LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7015 	LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7016 	LSM_HOOK_INIT(inode_create, selinux_inode_create),
7017 	LSM_HOOK_INIT(inode_link, selinux_inode_link),
7018 	LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7019 	LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7020 	LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7021 	LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7022 	LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7023 	LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7024 	LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7025 	LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7026 	LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7027 	LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7028 	LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7029 	LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7030 	LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7031 	LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7032 	LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7033 	LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7034 	LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7035 	LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7036 	LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7037 	LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7038 	LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7039 	LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7040 	LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7041 	LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7042 	LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7043 	LSM_HOOK_INIT(path_notify, selinux_path_notify),
7044 
7045 	LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7046 
7047 	LSM_HOOK_INIT(file_permission, selinux_file_permission),
7048 	LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7049 	LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7050 	LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7051 	LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7052 	LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7053 	LSM_HOOK_INIT(file_lock, selinux_file_lock),
7054 	LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7055 	LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7056 	LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7057 	LSM_HOOK_INIT(file_receive, selinux_file_receive),
7058 
7059 	LSM_HOOK_INIT(file_open, selinux_file_open),
7060 
7061 	LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7062 	LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7063 	LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7064 	LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7065 	LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7066 	LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7067 	LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7068 	LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7069 	LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7070 	LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7071 	LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7072 	LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7073 	LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj),
7074 	LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj),
7075 	LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7076 	LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7077 	LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7078 	LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7079 	LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7080 	LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7081 	LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7082 	LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7083 	LSM_HOOK_INIT(task_kill, selinux_task_kill),
7084 	LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7085 	LSM_HOOK_INIT(userns_create, selinux_userns_create),
7086 
7087 	LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7088 	LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7089 
7090 	LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7091 	LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7092 	LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7093 	LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7094 
7095 	LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7096 	LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7097 	LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7098 
7099 	LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7100 	LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7101 	LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7102 
7103 	LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7104 
7105 	LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7106 	LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7107 
7108 	LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7109 	LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7110 	LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7111 	LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7112 	LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7113 	LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7114 
7115 	LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7116 	LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7117 
7118 	LSM_HOOK_INIT(socket_create, selinux_socket_create),
7119 	LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7120 	LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7121 	LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7122 	LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7123 	LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7124 	LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7125 	LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7126 	LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7127 	LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7128 	LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7129 	LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7130 	LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7131 	LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7132 	LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7133 	LSM_HOOK_INIT(socket_getpeersec_stream,
7134 			selinux_socket_getpeersec_stream),
7135 	LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7136 	LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7137 	LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7138 	LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7139 	LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7140 	LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7141 	LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7142 	LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7143 	LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7144 	LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow),
7145 	LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7146 	LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7147 	LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7148 	LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7149 	LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7150 	LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7151 	LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7152 	LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7153 	LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7154 	LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7155 	LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7156 	LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7157 #ifdef CONFIG_SECURITY_INFINIBAND
7158 	LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7159 	LSM_HOOK_INIT(ib_endport_manage_subnet,
7160 		      selinux_ib_endport_manage_subnet),
7161 	LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7162 #endif
7163 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7164 	LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7165 	LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7166 	LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7167 	LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7168 	LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7169 	LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7170 			selinux_xfrm_state_pol_flow_match),
7171 	LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7172 #endif
7173 
7174 #ifdef CONFIG_KEYS
7175 	LSM_HOOK_INIT(key_free, selinux_key_free),
7176 	LSM_HOOK_INIT(key_permission, selinux_key_permission),
7177 	LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7178 #ifdef CONFIG_KEY_NOTIFICATIONS
7179 	LSM_HOOK_INIT(watch_key, selinux_watch_key),
7180 #endif
7181 #endif
7182 
7183 #ifdef CONFIG_AUDIT
7184 	LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7185 	LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7186 	LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7187 #endif
7188 
7189 #ifdef CONFIG_BPF_SYSCALL
7190 	LSM_HOOK_INIT(bpf, selinux_bpf),
7191 	LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7192 	LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7193 	LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7194 	LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7195 #endif
7196 
7197 #ifdef CONFIG_PERF_EVENTS
7198 	LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7199 	LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7200 	LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7201 	LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7202 #endif
7203 
7204 #ifdef CONFIG_IO_URING
7205 	LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7206 	LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7207 	LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7208 #endif
7209 
7210 	/*
7211 	 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7212 	 */
7213 	LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7214 	LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7215 	LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7216 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7217 	LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7218 #endif
7219 
7220 	/*
7221 	 * PUT "ALLOCATING" HOOKS HERE
7222 	 */
7223 	LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7224 	LSM_HOOK_INIT(msg_queue_alloc_security,
7225 		      selinux_msg_queue_alloc_security),
7226 	LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7227 	LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7228 	LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7229 	LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7230 	LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7231 	LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7232 	LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7233 	LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7234 #ifdef CONFIG_SECURITY_INFINIBAND
7235 	LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7236 #endif
7237 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7238 	LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7239 	LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7240 	LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7241 		      selinux_xfrm_state_alloc_acquire),
7242 #endif
7243 #ifdef CONFIG_KEYS
7244 	LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7245 #endif
7246 #ifdef CONFIG_AUDIT
7247 	LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7248 #endif
7249 #ifdef CONFIG_BPF_SYSCALL
7250 	LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7251 	LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7252 #endif
7253 #ifdef CONFIG_PERF_EVENTS
7254 	LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7255 #endif
7256 };
7257 
7258 static __init int selinux_init(void)
7259 {
7260 	pr_info("SELinux:  Initializing.\n");
7261 
7262 	memset(&selinux_state, 0, sizeof(selinux_state));
7263 	enforcing_set(selinux_enforcing_boot);
7264 	selinux_avc_init();
7265 	mutex_init(&selinux_state.status_lock);
7266 	mutex_init(&selinux_state.policy_mutex);
7267 
7268 	/* Set the security state for the initial task. */
7269 	cred_init_security();
7270 
7271 	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7272 
7273 	avc_init();
7274 
7275 	avtab_cache_init();
7276 
7277 	ebitmap_cache_init();
7278 
7279 	hashtab_cache_init();
7280 
7281 	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7282 
7283 	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7284 		panic("SELinux: Unable to register AVC netcache callback\n");
7285 
7286 	if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7287 		panic("SELinux: Unable to register AVC LSM notifier callback\n");
7288 
7289 	if (selinux_enforcing_boot)
7290 		pr_debug("SELinux:  Starting in enforcing mode\n");
7291 	else
7292 		pr_debug("SELinux:  Starting in permissive mode\n");
7293 
7294 	fs_validate_description("selinux", selinux_fs_parameters);
7295 
7296 	return 0;
7297 }
7298 
7299 static void delayed_superblock_init(struct super_block *sb, void *unused)
7300 {
7301 	selinux_set_mnt_opts(sb, NULL, 0, NULL);
7302 }
7303 
7304 void selinux_complete_init(void)
7305 {
7306 	pr_debug("SELinux:  Completing initialization.\n");
7307 
7308 	/* Set up any superblocks initialized prior to the policy load. */
7309 	pr_debug("SELinux:  Setting up existing superblocks.\n");
7310 	iterate_supers(delayed_superblock_init, NULL);
7311 }
7312 
7313 /* SELinux requires early initialization in order to label
7314    all processes and objects when they are created. */
7315 DEFINE_LSM(selinux) = {
7316 	.name = "selinux",
7317 	.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7318 	.enabled = &selinux_enabled_boot,
7319 	.blobs = &selinux_blob_sizes,
7320 	.init = selinux_init,
7321 };
7322 
7323 #if defined(CONFIG_NETFILTER)
7324 static const struct nf_hook_ops selinux_nf_ops[] = {
7325 	{
7326 		.hook =		selinux_ip_postroute,
7327 		.pf =		NFPROTO_IPV4,
7328 		.hooknum =	NF_INET_POST_ROUTING,
7329 		.priority =	NF_IP_PRI_SELINUX_LAST,
7330 	},
7331 	{
7332 		.hook =		selinux_ip_forward,
7333 		.pf =		NFPROTO_IPV4,
7334 		.hooknum =	NF_INET_FORWARD,
7335 		.priority =	NF_IP_PRI_SELINUX_FIRST,
7336 	},
7337 	{
7338 		.hook =		selinux_ip_output,
7339 		.pf =		NFPROTO_IPV4,
7340 		.hooknum =	NF_INET_LOCAL_OUT,
7341 		.priority =	NF_IP_PRI_SELINUX_FIRST,
7342 	},
7343 #if IS_ENABLED(CONFIG_IPV6)
7344 	{
7345 		.hook =		selinux_ip_postroute,
7346 		.pf =		NFPROTO_IPV6,
7347 		.hooknum =	NF_INET_POST_ROUTING,
7348 		.priority =	NF_IP6_PRI_SELINUX_LAST,
7349 	},
7350 	{
7351 		.hook =		selinux_ip_forward,
7352 		.pf =		NFPROTO_IPV6,
7353 		.hooknum =	NF_INET_FORWARD,
7354 		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7355 	},
7356 	{
7357 		.hook =		selinux_ip_output,
7358 		.pf =		NFPROTO_IPV6,
7359 		.hooknum =	NF_INET_LOCAL_OUT,
7360 		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7361 	},
7362 #endif	/* IPV6 */
7363 };
7364 
7365 static int __net_init selinux_nf_register(struct net *net)
7366 {
7367 	return nf_register_net_hooks(net, selinux_nf_ops,
7368 				     ARRAY_SIZE(selinux_nf_ops));
7369 }
7370 
7371 static void __net_exit selinux_nf_unregister(struct net *net)
7372 {
7373 	nf_unregister_net_hooks(net, selinux_nf_ops,
7374 				ARRAY_SIZE(selinux_nf_ops));
7375 }
7376 
7377 static struct pernet_operations selinux_net_ops = {
7378 	.init = selinux_nf_register,
7379 	.exit = selinux_nf_unregister,
7380 };
7381 
7382 static int __init selinux_nf_ip_init(void)
7383 {
7384 	int err;
7385 
7386 	if (!selinux_enabled_boot)
7387 		return 0;
7388 
7389 	pr_debug("SELinux:  Registering netfilter hooks\n");
7390 
7391 	err = register_pernet_subsys(&selinux_net_ops);
7392 	if (err)
7393 		panic("SELinux: register_pernet_subsys: error %d\n", err);
7394 
7395 	return 0;
7396 }
7397 __initcall(selinux_nf_ip_init);
7398 #endif /* CONFIG_NETFILTER */
7399