xref: /linux/security/selinux/hooks.c (revision f2586d921cea4feeddd1cc5ee3495700540dba8f)
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 	if (old_tsec->exec_sid) {
2292 		new_tsec->sid = old_tsec->exec_sid;
2293 		/* Reset exec SID on execve. */
2294 		new_tsec->exec_sid = 0;
2295 
2296 		/* Fail on NNP or nosuid if not an allowed transition. */
2297 		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2298 		if (rc)
2299 			return rc;
2300 	} else {
2301 		/* Check for a default transition on this program. */
2302 		rc = security_transition_sid(old_tsec->sid,
2303 					     isec->sid, SECCLASS_PROCESS, NULL,
2304 					     &new_tsec->sid);
2305 		if (rc)
2306 			return rc;
2307 
2308 		/*
2309 		 * Fallback to old SID on NNP or nosuid if not an allowed
2310 		 * transition.
2311 		 */
2312 		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2313 		if (rc)
2314 			new_tsec->sid = old_tsec->sid;
2315 	}
2316 
2317 	ad.type = LSM_AUDIT_DATA_FILE;
2318 	ad.u.file = bprm->file;
2319 
2320 	if (new_tsec->sid == old_tsec->sid) {
2321 		rc = avc_has_perm(old_tsec->sid, isec->sid,
2322 				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2323 		if (rc)
2324 			return rc;
2325 	} else {
2326 		/* Check permissions for the transition. */
2327 		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2328 				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2329 		if (rc)
2330 			return rc;
2331 
2332 		rc = avc_has_perm(new_tsec->sid, isec->sid,
2333 				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2334 		if (rc)
2335 			return rc;
2336 
2337 		/* Check for shared state */
2338 		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2339 			rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2340 					  SECCLASS_PROCESS, PROCESS__SHARE,
2341 					  NULL);
2342 			if (rc)
2343 				return -EPERM;
2344 		}
2345 
2346 		/* Make sure that anyone attempting to ptrace over a task that
2347 		 * changes its SID has the appropriate permit */
2348 		if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2349 			u32 ptsid = ptrace_parent_sid();
2350 			if (ptsid != 0) {
2351 				rc = avc_has_perm(ptsid, new_tsec->sid,
2352 						  SECCLASS_PROCESS,
2353 						  PROCESS__PTRACE, NULL);
2354 				if (rc)
2355 					return -EPERM;
2356 			}
2357 		}
2358 
2359 		/* Clear any possibly unsafe personality bits on exec: */
2360 		bprm->per_clear |= PER_CLEAR_ON_SETID;
2361 
2362 		/* Enable secure mode for SIDs transitions unless
2363 		   the noatsecure permission is granted between
2364 		   the two SIDs, i.e. ahp returns 0. */
2365 		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2366 				  SECCLASS_PROCESS, PROCESS__NOATSECURE,
2367 				  NULL);
2368 		bprm->secureexec |= !!rc;
2369 	}
2370 
2371 	return 0;
2372 }
2373 
2374 static int match_file(const void *p, struct file *file, unsigned fd)
2375 {
2376 	return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2377 }
2378 
2379 /* Derived from fs/exec.c:flush_old_files. */
2380 static inline void flush_unauthorized_files(const struct cred *cred,
2381 					    struct files_struct *files)
2382 {
2383 	struct file *file, *devnull = NULL;
2384 	struct tty_struct *tty;
2385 	int drop_tty = 0;
2386 	unsigned n;
2387 
2388 	tty = get_current_tty();
2389 	if (tty) {
2390 		spin_lock(&tty->files_lock);
2391 		if (!list_empty(&tty->tty_files)) {
2392 			struct tty_file_private *file_priv;
2393 
2394 			/* Revalidate access to controlling tty.
2395 			   Use file_path_has_perm on the tty path directly
2396 			   rather than using file_has_perm, as this particular
2397 			   open file may belong to another process and we are
2398 			   only interested in the inode-based check here. */
2399 			file_priv = list_first_entry(&tty->tty_files,
2400 						struct tty_file_private, list);
2401 			file = file_priv->file;
2402 			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2403 				drop_tty = 1;
2404 		}
2405 		spin_unlock(&tty->files_lock);
2406 		tty_kref_put(tty);
2407 	}
2408 	/* Reset controlling tty. */
2409 	if (drop_tty)
2410 		no_tty();
2411 
2412 	/* Revalidate access to inherited open files. */
2413 	n = iterate_fd(files, 0, match_file, cred);
2414 	if (!n) /* none found? */
2415 		return;
2416 
2417 	devnull = dentry_open(&selinux_null, O_RDWR, cred);
2418 	if (IS_ERR(devnull))
2419 		devnull = NULL;
2420 	/* replace all the matching ones with this */
2421 	do {
2422 		replace_fd(n - 1, devnull, 0);
2423 	} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2424 	if (devnull)
2425 		fput(devnull);
2426 }
2427 
2428 /*
2429  * Prepare a process for imminent new credential changes due to exec
2430  */
2431 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2432 {
2433 	struct task_security_struct *new_tsec;
2434 	struct rlimit *rlim, *initrlim;
2435 	int rc, i;
2436 
2437 	new_tsec = selinux_cred(bprm->cred);
2438 	if (new_tsec->sid == new_tsec->osid)
2439 		return;
2440 
2441 	/* Close files for which the new task SID is not authorized. */
2442 	flush_unauthorized_files(bprm->cred, current->files);
2443 
2444 	/* Always clear parent death signal on SID transitions. */
2445 	current->pdeath_signal = 0;
2446 
2447 	/* Check whether the new SID can inherit resource limits from the old
2448 	 * SID.  If not, reset all soft limits to the lower of the current
2449 	 * task's hard limit and the init task's soft limit.
2450 	 *
2451 	 * Note that the setting of hard limits (even to lower them) can be
2452 	 * controlled by the setrlimit check.  The inclusion of the init task's
2453 	 * soft limit into the computation is to avoid resetting soft limits
2454 	 * higher than the default soft limit for cases where the default is
2455 	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2456 	 */
2457 	rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2458 			  PROCESS__RLIMITINH, NULL);
2459 	if (rc) {
2460 		/* protect against do_prlimit() */
2461 		task_lock(current);
2462 		for (i = 0; i < RLIM_NLIMITS; i++) {
2463 			rlim = current->signal->rlim + i;
2464 			initrlim = init_task.signal->rlim + i;
2465 			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2466 		}
2467 		task_unlock(current);
2468 		if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2469 			update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2470 	}
2471 }
2472 
2473 /*
2474  * Clean up the process immediately after the installation of new credentials
2475  * due to exec
2476  */
2477 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2478 {
2479 	const struct task_security_struct *tsec = selinux_cred(current_cred());
2480 	u32 osid, sid;
2481 	int rc;
2482 
2483 	osid = tsec->osid;
2484 	sid = tsec->sid;
2485 
2486 	if (sid == osid)
2487 		return;
2488 
2489 	/* Check whether the new SID can inherit signal state from the old SID.
2490 	 * If not, clear itimers to avoid subsequent signal generation and
2491 	 * flush and unblock signals.
2492 	 *
2493 	 * This must occur _after_ the task SID has been updated so that any
2494 	 * kill done after the flush will be checked against the new SID.
2495 	 */
2496 	rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2497 	if (rc) {
2498 		clear_itimer();
2499 
2500 		spin_lock_irq(&unrcu_pointer(current->sighand)->siglock);
2501 		if (!fatal_signal_pending(current)) {
2502 			flush_sigqueue(&current->pending);
2503 			flush_sigqueue(&current->signal->shared_pending);
2504 			flush_signal_handlers(current, 1);
2505 			sigemptyset(&current->blocked);
2506 			recalc_sigpending();
2507 		}
2508 		spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock);
2509 	}
2510 
2511 	/* Wake up the parent if it is waiting so that it can recheck
2512 	 * wait permission to the new task SID. */
2513 	read_lock(&tasklist_lock);
2514 	__wake_up_parent(current, unrcu_pointer(current->real_parent));
2515 	read_unlock(&tasklist_lock);
2516 }
2517 
2518 /* superblock security operations */
2519 
2520 static int selinux_sb_alloc_security(struct super_block *sb)
2521 {
2522 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
2523 
2524 	mutex_init(&sbsec->lock);
2525 	INIT_LIST_HEAD(&sbsec->isec_head);
2526 	spin_lock_init(&sbsec->isec_lock);
2527 	sbsec->sid = SECINITSID_UNLABELED;
2528 	sbsec->def_sid = SECINITSID_FILE;
2529 	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2530 
2531 	return 0;
2532 }
2533 
2534 static inline int opt_len(const char *s)
2535 {
2536 	bool open_quote = false;
2537 	int len;
2538 	char c;
2539 
2540 	for (len = 0; (c = s[len]) != '\0'; len++) {
2541 		if (c == '"')
2542 			open_quote = !open_quote;
2543 		if (c == ',' && !open_quote)
2544 			break;
2545 	}
2546 	return len;
2547 }
2548 
2549 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2550 {
2551 	char *from = options;
2552 	char *to = options;
2553 	bool first = true;
2554 	int rc;
2555 
2556 	while (1) {
2557 		int len = opt_len(from);
2558 		int token;
2559 		char *arg = NULL;
2560 
2561 		token = match_opt_prefix(from, len, &arg);
2562 
2563 		if (token != Opt_error) {
2564 			char *p, *q;
2565 
2566 			/* strip quotes */
2567 			if (arg) {
2568 				for (p = q = arg; p < from + len; p++) {
2569 					char c = *p;
2570 					if (c != '"')
2571 						*q++ = c;
2572 				}
2573 				arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2574 				if (!arg) {
2575 					rc = -ENOMEM;
2576 					goto free_opt;
2577 				}
2578 			}
2579 			rc = selinux_add_opt(token, arg, mnt_opts);
2580 			kfree(arg);
2581 			arg = NULL;
2582 			if (unlikely(rc)) {
2583 				goto free_opt;
2584 			}
2585 		} else {
2586 			if (!first) {	// copy with preceding comma
2587 				from--;
2588 				len++;
2589 			}
2590 			if (to != from)
2591 				memmove(to, from, len);
2592 			to += len;
2593 			first = false;
2594 		}
2595 		if (!from[len])
2596 			break;
2597 		from += len + 1;
2598 	}
2599 	*to = '\0';
2600 	return 0;
2601 
2602 free_opt:
2603 	if (*mnt_opts) {
2604 		selinux_free_mnt_opts(*mnt_opts);
2605 		*mnt_opts = NULL;
2606 	}
2607 	return rc;
2608 }
2609 
2610 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
2611 {
2612 	struct selinux_mnt_opts *opts = mnt_opts;
2613 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
2614 
2615 	/*
2616 	 * Superblock not initialized (i.e. no options) - reject if any
2617 	 * options specified, otherwise accept.
2618 	 */
2619 	if (!(sbsec->flags & SE_SBINITIALIZED))
2620 		return opts ? 1 : 0;
2621 
2622 	/*
2623 	 * Superblock initialized and no options specified - reject if
2624 	 * superblock has any options set, otherwise accept.
2625 	 */
2626 	if (!opts)
2627 		return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2628 
2629 	if (opts->fscontext_sid) {
2630 		if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2631 			       opts->fscontext_sid))
2632 			return 1;
2633 	}
2634 	if (opts->context_sid) {
2635 		if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2636 			       opts->context_sid))
2637 			return 1;
2638 	}
2639 	if (opts->rootcontext_sid) {
2640 		struct inode_security_struct *root_isec;
2641 
2642 		root_isec = backing_inode_security(sb->s_root);
2643 		if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2644 			       opts->rootcontext_sid))
2645 			return 1;
2646 	}
2647 	if (opts->defcontext_sid) {
2648 		if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2649 			       opts->defcontext_sid))
2650 			return 1;
2651 	}
2652 	return 0;
2653 }
2654 
2655 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2656 {
2657 	struct selinux_mnt_opts *opts = mnt_opts;
2658 	struct superblock_security_struct *sbsec = selinux_superblock(sb);
2659 
2660 	if (!(sbsec->flags & SE_SBINITIALIZED))
2661 		return 0;
2662 
2663 	if (!opts)
2664 		return 0;
2665 
2666 	if (opts->fscontext_sid) {
2667 		if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2668 			       opts->fscontext_sid))
2669 			goto out_bad_option;
2670 	}
2671 	if (opts->context_sid) {
2672 		if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2673 			       opts->context_sid))
2674 			goto out_bad_option;
2675 	}
2676 	if (opts->rootcontext_sid) {
2677 		struct inode_security_struct *root_isec;
2678 		root_isec = backing_inode_security(sb->s_root);
2679 		if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2680 			       opts->rootcontext_sid))
2681 			goto out_bad_option;
2682 	}
2683 	if (opts->defcontext_sid) {
2684 		if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2685 			       opts->defcontext_sid))
2686 			goto out_bad_option;
2687 	}
2688 	return 0;
2689 
2690 out_bad_option:
2691 	pr_warn("SELinux: unable to change security options "
2692 	       "during remount (dev %s, type=%s)\n", sb->s_id,
2693 	       sb->s_type->name);
2694 	return -EINVAL;
2695 }
2696 
2697 static int selinux_sb_kern_mount(struct super_block *sb)
2698 {
2699 	const struct cred *cred = current_cred();
2700 	struct common_audit_data ad;
2701 
2702 	ad.type = LSM_AUDIT_DATA_DENTRY;
2703 	ad.u.dentry = sb->s_root;
2704 	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2705 }
2706 
2707 static int selinux_sb_statfs(struct dentry *dentry)
2708 {
2709 	const struct cred *cred = current_cred();
2710 	struct common_audit_data ad;
2711 
2712 	ad.type = LSM_AUDIT_DATA_DENTRY;
2713 	ad.u.dentry = dentry->d_sb->s_root;
2714 	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2715 }
2716 
2717 static int selinux_mount(const char *dev_name,
2718 			 const struct path *path,
2719 			 const char *type,
2720 			 unsigned long flags,
2721 			 void *data)
2722 {
2723 	const struct cred *cred = current_cred();
2724 
2725 	if (flags & MS_REMOUNT)
2726 		return superblock_has_perm(cred, path->dentry->d_sb,
2727 					   FILESYSTEM__REMOUNT, NULL);
2728 	else
2729 		return path_has_perm(cred, path, FILE__MOUNTON);
2730 }
2731 
2732 static int selinux_move_mount(const struct path *from_path,
2733 			      const struct path *to_path)
2734 {
2735 	const struct cred *cred = current_cred();
2736 
2737 	return path_has_perm(cred, to_path, FILE__MOUNTON);
2738 }
2739 
2740 static int selinux_umount(struct vfsmount *mnt, int flags)
2741 {
2742 	const struct cred *cred = current_cred();
2743 
2744 	return superblock_has_perm(cred, mnt->mnt_sb,
2745 				   FILESYSTEM__UNMOUNT, NULL);
2746 }
2747 
2748 static int selinux_fs_context_submount(struct fs_context *fc,
2749 				   struct super_block *reference)
2750 {
2751 	const struct superblock_security_struct *sbsec;
2752 	struct selinux_mnt_opts *opts;
2753 
2754 	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
2755 	if (!opts)
2756 		return -ENOMEM;
2757 
2758 	sbsec = selinux_superblock(reference);
2759 	if (sbsec->flags & FSCONTEXT_MNT)
2760 		opts->fscontext_sid = sbsec->sid;
2761 	if (sbsec->flags & CONTEXT_MNT)
2762 		opts->context_sid = sbsec->mntpoint_sid;
2763 	if (sbsec->flags & DEFCONTEXT_MNT)
2764 		opts->defcontext_sid = sbsec->def_sid;
2765 	fc->security = opts;
2766 	return 0;
2767 }
2768 
2769 static int selinux_fs_context_dup(struct fs_context *fc,
2770 				  struct fs_context *src_fc)
2771 {
2772 	const struct selinux_mnt_opts *src = src_fc->security;
2773 
2774 	if (!src)
2775 		return 0;
2776 
2777 	fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL);
2778 	return fc->security ? 0 : -ENOMEM;
2779 }
2780 
2781 static const struct fs_parameter_spec selinux_fs_parameters[] = {
2782 	fsparam_string(CONTEXT_STR,	Opt_context),
2783 	fsparam_string(DEFCONTEXT_STR,	Opt_defcontext),
2784 	fsparam_string(FSCONTEXT_STR,	Opt_fscontext),
2785 	fsparam_string(ROOTCONTEXT_STR,	Opt_rootcontext),
2786 	fsparam_flag  (SECLABEL_STR,	Opt_seclabel),
2787 	{}
2788 };
2789 
2790 static int selinux_fs_context_parse_param(struct fs_context *fc,
2791 					  struct fs_parameter *param)
2792 {
2793 	struct fs_parse_result result;
2794 	int opt;
2795 
2796 	opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2797 	if (opt < 0)
2798 		return opt;
2799 
2800 	return selinux_add_opt(opt, param->string, &fc->security);
2801 }
2802 
2803 /* inode security operations */
2804 
2805 static int selinux_inode_alloc_security(struct inode *inode)
2806 {
2807 	struct inode_security_struct *isec = selinux_inode(inode);
2808 	u32 sid = current_sid();
2809 
2810 	spin_lock_init(&isec->lock);
2811 	INIT_LIST_HEAD(&isec->list);
2812 	isec->inode = inode;
2813 	isec->sid = SECINITSID_UNLABELED;
2814 	isec->sclass = SECCLASS_FILE;
2815 	isec->task_sid = sid;
2816 	isec->initialized = LABEL_INVALID;
2817 
2818 	return 0;
2819 }
2820 
2821 static void selinux_inode_free_security(struct inode *inode)
2822 {
2823 	inode_free_security(inode);
2824 }
2825 
2826 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2827 					const struct qstr *name,
2828 					const char **xattr_name, void **ctx,
2829 					u32 *ctxlen)
2830 {
2831 	u32 newsid;
2832 	int rc;
2833 
2834 	rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2835 					   d_inode(dentry->d_parent), name,
2836 					   inode_mode_to_security_class(mode),
2837 					   &newsid);
2838 	if (rc)
2839 		return rc;
2840 
2841 	if (xattr_name)
2842 		*xattr_name = XATTR_NAME_SELINUX;
2843 
2844 	return security_sid_to_context(newsid, (char **)ctx,
2845 				       ctxlen);
2846 }
2847 
2848 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2849 					  struct qstr *name,
2850 					  const struct cred *old,
2851 					  struct cred *new)
2852 {
2853 	u32 newsid;
2854 	int rc;
2855 	struct task_security_struct *tsec;
2856 
2857 	rc = selinux_determine_inode_label(selinux_cred(old),
2858 					   d_inode(dentry->d_parent), name,
2859 					   inode_mode_to_security_class(mode),
2860 					   &newsid);
2861 	if (rc)
2862 		return rc;
2863 
2864 	tsec = selinux_cred(new);
2865 	tsec->create_sid = newsid;
2866 	return 0;
2867 }
2868 
2869 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2870 				       const struct qstr *qstr,
2871 				       const char **name,
2872 				       void **value, size_t *len)
2873 {
2874 	const struct task_security_struct *tsec = selinux_cred(current_cred());
2875 	struct superblock_security_struct *sbsec;
2876 	u32 newsid, clen;
2877 	int rc;
2878 	char *context;
2879 
2880 	sbsec = selinux_superblock(dir->i_sb);
2881 
2882 	newsid = tsec->create_sid;
2883 
2884 	rc = selinux_determine_inode_label(tsec, dir, qstr,
2885 		inode_mode_to_security_class(inode->i_mode),
2886 		&newsid);
2887 	if (rc)
2888 		return rc;
2889 
2890 	/* Possibly defer initialization to selinux_complete_init. */
2891 	if (sbsec->flags & SE_SBINITIALIZED) {
2892 		struct inode_security_struct *isec = selinux_inode(inode);
2893 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
2894 		isec->sid = newsid;
2895 		isec->initialized = LABEL_INITIALIZED;
2896 	}
2897 
2898 	if (!selinux_initialized() ||
2899 	    !(sbsec->flags & SBLABEL_MNT))
2900 		return -EOPNOTSUPP;
2901 
2902 	if (name)
2903 		*name = XATTR_SELINUX_SUFFIX;
2904 
2905 	if (value && len) {
2906 		rc = security_sid_to_context_force(newsid,
2907 						   &context, &clen);
2908 		if (rc)
2909 			return rc;
2910 		*value = context;
2911 		*len = clen;
2912 	}
2913 
2914 	return 0;
2915 }
2916 
2917 static int selinux_inode_init_security_anon(struct inode *inode,
2918 					    const struct qstr *name,
2919 					    const struct inode *context_inode)
2920 {
2921 	const struct task_security_struct *tsec = selinux_cred(current_cred());
2922 	struct common_audit_data ad;
2923 	struct inode_security_struct *isec;
2924 	int rc;
2925 
2926 	if (unlikely(!selinux_initialized()))
2927 		return 0;
2928 
2929 	isec = selinux_inode(inode);
2930 
2931 	/*
2932 	 * We only get here once per ephemeral inode.  The inode has
2933 	 * been initialized via inode_alloc_security but is otherwise
2934 	 * untouched.
2935 	 */
2936 
2937 	if (context_inode) {
2938 		struct inode_security_struct *context_isec =
2939 			selinux_inode(context_inode);
2940 		if (context_isec->initialized != LABEL_INITIALIZED) {
2941 			pr_err("SELinux:  context_inode is not initialized");
2942 			return -EACCES;
2943 		}
2944 
2945 		isec->sclass = context_isec->sclass;
2946 		isec->sid = context_isec->sid;
2947 	} else {
2948 		isec->sclass = SECCLASS_ANON_INODE;
2949 		rc = security_transition_sid(
2950 			tsec->sid, tsec->sid,
2951 			isec->sclass, name, &isec->sid);
2952 		if (rc)
2953 			return rc;
2954 	}
2955 
2956 	isec->initialized = LABEL_INITIALIZED;
2957 	/*
2958 	 * Now that we've initialized security, check whether we're
2959 	 * allowed to actually create this type of anonymous inode.
2960 	 */
2961 
2962 	ad.type = LSM_AUDIT_DATA_ANONINODE;
2963 	ad.u.anonclass = name ? (const char *)name->name : "?";
2964 
2965 	return avc_has_perm(tsec->sid,
2966 			    isec->sid,
2967 			    isec->sclass,
2968 			    FILE__CREATE,
2969 			    &ad);
2970 }
2971 
2972 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2973 {
2974 	return may_create(dir, dentry, SECCLASS_FILE);
2975 }
2976 
2977 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2978 {
2979 	return may_link(dir, old_dentry, MAY_LINK);
2980 }
2981 
2982 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2983 {
2984 	return may_link(dir, dentry, MAY_UNLINK);
2985 }
2986 
2987 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2988 {
2989 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
2990 }
2991 
2992 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2993 {
2994 	return may_create(dir, dentry, SECCLASS_DIR);
2995 }
2996 
2997 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2998 {
2999 	return may_link(dir, dentry, MAY_RMDIR);
3000 }
3001 
3002 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3003 {
3004 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
3005 }
3006 
3007 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3008 				struct inode *new_inode, struct dentry *new_dentry)
3009 {
3010 	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3011 }
3012 
3013 static int selinux_inode_readlink(struct dentry *dentry)
3014 {
3015 	const struct cred *cred = current_cred();
3016 
3017 	return dentry_has_perm(cred, dentry, FILE__READ);
3018 }
3019 
3020 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3021 				     bool rcu)
3022 {
3023 	const struct cred *cred = current_cred();
3024 	struct common_audit_data ad;
3025 	struct inode_security_struct *isec;
3026 	u32 sid;
3027 
3028 	validate_creds(cred);
3029 
3030 	ad.type = LSM_AUDIT_DATA_DENTRY;
3031 	ad.u.dentry = dentry;
3032 	sid = cred_sid(cred);
3033 	isec = inode_security_rcu(inode, rcu);
3034 	if (IS_ERR(isec))
3035 		return PTR_ERR(isec);
3036 
3037 	return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad);
3038 }
3039 
3040 static noinline int audit_inode_permission(struct inode *inode,
3041 					   u32 perms, u32 audited, u32 denied,
3042 					   int result)
3043 {
3044 	struct common_audit_data ad;
3045 	struct inode_security_struct *isec = selinux_inode(inode);
3046 
3047 	ad.type = LSM_AUDIT_DATA_INODE;
3048 	ad.u.inode = inode;
3049 
3050 	return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3051 			    audited, denied, result, &ad);
3052 }
3053 
3054 static int selinux_inode_permission(struct inode *inode, int mask)
3055 {
3056 	const struct cred *cred = current_cred();
3057 	u32 perms;
3058 	bool from_access;
3059 	bool no_block = mask & MAY_NOT_BLOCK;
3060 	struct inode_security_struct *isec;
3061 	u32 sid;
3062 	struct av_decision avd;
3063 	int rc, rc2;
3064 	u32 audited, denied;
3065 
3066 	from_access = mask & MAY_ACCESS;
3067 	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3068 
3069 	/* No permission to check.  Existence test. */
3070 	if (!mask)
3071 		return 0;
3072 
3073 	validate_creds(cred);
3074 
3075 	if (unlikely(IS_PRIVATE(inode)))
3076 		return 0;
3077 
3078 	perms = file_mask_to_av(inode->i_mode, mask);
3079 
3080 	sid = cred_sid(cred);
3081 	isec = inode_security_rcu(inode, no_block);
3082 	if (IS_ERR(isec))
3083 		return PTR_ERR(isec);
3084 
3085 	rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0,
3086 				  &avd);
3087 	audited = avc_audit_required(perms, &avd, rc,
3088 				     from_access ? FILE__AUDIT_ACCESS : 0,
3089 				     &denied);
3090 	if (likely(!audited))
3091 		return rc;
3092 
3093 	rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3094 	if (rc2)
3095 		return rc2;
3096 	return rc;
3097 }
3098 
3099 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3100 {
3101 	const struct cred *cred = current_cred();
3102 	struct inode *inode = d_backing_inode(dentry);
3103 	unsigned int ia_valid = iattr->ia_valid;
3104 	__u32 av = FILE__WRITE;
3105 
3106 	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3107 	if (ia_valid & ATTR_FORCE) {
3108 		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3109 			      ATTR_FORCE);
3110 		if (!ia_valid)
3111 			return 0;
3112 	}
3113 
3114 	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3115 			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3116 		return dentry_has_perm(cred, dentry, FILE__SETATTR);
3117 
3118 	if (selinux_policycap_openperm() &&
3119 	    inode->i_sb->s_magic != SOCKFS_MAGIC &&
3120 	    (ia_valid & ATTR_SIZE) &&
3121 	    !(ia_valid & ATTR_FILE))
3122 		av |= FILE__OPEN;
3123 
3124 	return dentry_has_perm(cred, dentry, av);
3125 }
3126 
3127 static int selinux_inode_getattr(const struct path *path)
3128 {
3129 	return path_has_perm(current_cred(), path, FILE__GETATTR);
3130 }
3131 
3132 static bool has_cap_mac_admin(bool audit)
3133 {
3134 	const struct cred *cred = current_cred();
3135 	unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3136 
3137 	if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3138 		return false;
3139 	if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3140 		return false;
3141 	return true;
3142 }
3143 
3144 static int selinux_inode_setxattr(struct mnt_idmap *idmap,
3145 				  struct dentry *dentry, const char *name,
3146 				  const void *value, size_t size, int flags)
3147 {
3148 	struct inode *inode = d_backing_inode(dentry);
3149 	struct inode_security_struct *isec;
3150 	struct superblock_security_struct *sbsec;
3151 	struct common_audit_data ad;
3152 	u32 newsid, sid = current_sid();
3153 	int rc = 0;
3154 
3155 	if (strcmp(name, XATTR_NAME_SELINUX)) {
3156 		rc = cap_inode_setxattr(dentry, name, value, size, flags);
3157 		if (rc)
3158 			return rc;
3159 
3160 		/* Not an attribute we recognize, so just check the
3161 		   ordinary setattr permission. */
3162 		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3163 	}
3164 
3165 	if (!selinux_initialized())
3166 		return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM);
3167 
3168 	sbsec = selinux_superblock(inode->i_sb);
3169 	if (!(sbsec->flags & SBLABEL_MNT))
3170 		return -EOPNOTSUPP;
3171 
3172 	if (!inode_owner_or_capable(idmap, inode))
3173 		return -EPERM;
3174 
3175 	ad.type = LSM_AUDIT_DATA_DENTRY;
3176 	ad.u.dentry = dentry;
3177 
3178 	isec = backing_inode_security(dentry);
3179 	rc = avc_has_perm(sid, isec->sid, isec->sclass,
3180 			  FILE__RELABELFROM, &ad);
3181 	if (rc)
3182 		return rc;
3183 
3184 	rc = security_context_to_sid(value, size, &newsid,
3185 				     GFP_KERNEL);
3186 	if (rc == -EINVAL) {
3187 		if (!has_cap_mac_admin(true)) {
3188 			struct audit_buffer *ab;
3189 			size_t audit_size;
3190 
3191 			/* We strip a nul only if it is at the end, otherwise the
3192 			 * context contains a nul and we should audit that */
3193 			if (value) {
3194 				const char *str = value;
3195 
3196 				if (str[size - 1] == '\0')
3197 					audit_size = size - 1;
3198 				else
3199 					audit_size = size;
3200 			} else {
3201 				audit_size = 0;
3202 			}
3203 			ab = audit_log_start(audit_context(),
3204 					     GFP_ATOMIC, AUDIT_SELINUX_ERR);
3205 			if (!ab)
3206 				return rc;
3207 			audit_log_format(ab, "op=setxattr invalid_context=");
3208 			audit_log_n_untrustedstring(ab, value, audit_size);
3209 			audit_log_end(ab);
3210 
3211 			return rc;
3212 		}
3213 		rc = security_context_to_sid_force(value,
3214 						   size, &newsid);
3215 	}
3216 	if (rc)
3217 		return rc;
3218 
3219 	rc = avc_has_perm(sid, newsid, isec->sclass,
3220 			  FILE__RELABELTO, &ad);
3221 	if (rc)
3222 		return rc;
3223 
3224 	rc = security_validate_transition(isec->sid, newsid,
3225 					  sid, isec->sclass);
3226 	if (rc)
3227 		return rc;
3228 
3229 	return avc_has_perm(newsid,
3230 			    sbsec->sid,
3231 			    SECCLASS_FILESYSTEM,
3232 			    FILESYSTEM__ASSOCIATE,
3233 			    &ad);
3234 }
3235 
3236 static int selinux_inode_set_acl(struct mnt_idmap *idmap,
3237 				 struct dentry *dentry, const char *acl_name,
3238 				 struct posix_acl *kacl)
3239 {
3240 	return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3241 }
3242 
3243 static int selinux_inode_get_acl(struct mnt_idmap *idmap,
3244 				 struct dentry *dentry, const char *acl_name)
3245 {
3246 	return dentry_has_perm(current_cred(), dentry, FILE__GETATTR);
3247 }
3248 
3249 static int selinux_inode_remove_acl(struct mnt_idmap *idmap,
3250 				    struct dentry *dentry, const char *acl_name)
3251 {
3252 	return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3253 }
3254 
3255 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3256 					const void *value, size_t size,
3257 					int flags)
3258 {
3259 	struct inode *inode = d_backing_inode(dentry);
3260 	struct inode_security_struct *isec;
3261 	u32 newsid;
3262 	int rc;
3263 
3264 	if (strcmp(name, XATTR_NAME_SELINUX)) {
3265 		/* Not an attribute we recognize, so nothing to do. */
3266 		return;
3267 	}
3268 
3269 	if (!selinux_initialized()) {
3270 		/* If we haven't even been initialized, then we can't validate
3271 		 * against a policy, so leave the label as invalid. It may
3272 		 * resolve to a valid label on the next revalidation try if
3273 		 * we've since initialized.
3274 		 */
3275 		return;
3276 	}
3277 
3278 	rc = security_context_to_sid_force(value, size,
3279 					   &newsid);
3280 	if (rc) {
3281 		pr_err("SELinux:  unable to map context to SID"
3282 		       "for (%s, %lu), rc=%d\n",
3283 		       inode->i_sb->s_id, inode->i_ino, -rc);
3284 		return;
3285 	}
3286 
3287 	isec = backing_inode_security(dentry);
3288 	spin_lock(&isec->lock);
3289 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3290 	isec->sid = newsid;
3291 	isec->initialized = LABEL_INITIALIZED;
3292 	spin_unlock(&isec->lock);
3293 }
3294 
3295 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3296 {
3297 	const struct cred *cred = current_cred();
3298 
3299 	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3300 }
3301 
3302 static int selinux_inode_listxattr(struct dentry *dentry)
3303 {
3304 	const struct cred *cred = current_cred();
3305 
3306 	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3307 }
3308 
3309 static int selinux_inode_removexattr(struct mnt_idmap *idmap,
3310 				     struct dentry *dentry, const char *name)
3311 {
3312 	if (strcmp(name, XATTR_NAME_SELINUX)) {
3313 		int rc = cap_inode_removexattr(idmap, dentry, name);
3314 		if (rc)
3315 			return rc;
3316 
3317 		/* Not an attribute we recognize, so just check the
3318 		   ordinary setattr permission. */
3319 		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3320 	}
3321 
3322 	if (!selinux_initialized())
3323 		return 0;
3324 
3325 	/* No one is allowed to remove a SELinux security label.
3326 	   You can change the label, but all data must be labeled. */
3327 	return -EACCES;
3328 }
3329 
3330 static int selinux_path_notify(const struct path *path, u64 mask,
3331 						unsigned int obj_type)
3332 {
3333 	int ret;
3334 	u32 perm;
3335 
3336 	struct common_audit_data ad;
3337 
3338 	ad.type = LSM_AUDIT_DATA_PATH;
3339 	ad.u.path = *path;
3340 
3341 	/*
3342 	 * Set permission needed based on the type of mark being set.
3343 	 * Performs an additional check for sb watches.
3344 	 */
3345 	switch (obj_type) {
3346 	case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3347 		perm = FILE__WATCH_MOUNT;
3348 		break;
3349 	case FSNOTIFY_OBJ_TYPE_SB:
3350 		perm = FILE__WATCH_SB;
3351 		ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3352 						FILESYSTEM__WATCH, &ad);
3353 		if (ret)
3354 			return ret;
3355 		break;
3356 	case FSNOTIFY_OBJ_TYPE_INODE:
3357 		perm = FILE__WATCH;
3358 		break;
3359 	default:
3360 		return -EINVAL;
3361 	}
3362 
3363 	/* blocking watches require the file:watch_with_perm permission */
3364 	if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3365 		perm |= FILE__WATCH_WITH_PERM;
3366 
3367 	/* watches on read-like events need the file:watch_reads permission */
3368 	if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3369 		perm |= FILE__WATCH_READS;
3370 
3371 	return path_has_perm(current_cred(), path, perm);
3372 }
3373 
3374 /*
3375  * Copy the inode security context value to the user.
3376  *
3377  * Permission check is handled by selinux_inode_getxattr hook.
3378  */
3379 static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3380 				     struct inode *inode, const char *name,
3381 				     void **buffer, bool alloc)
3382 {
3383 	u32 size;
3384 	int error;
3385 	char *context = NULL;
3386 	struct inode_security_struct *isec;
3387 
3388 	/*
3389 	 * If we're not initialized yet, then we can't validate contexts, so
3390 	 * just let vfs_getxattr fall back to using the on-disk xattr.
3391 	 */
3392 	if (!selinux_initialized() ||
3393 	    strcmp(name, XATTR_SELINUX_SUFFIX))
3394 		return -EOPNOTSUPP;
3395 
3396 	/*
3397 	 * If the caller has CAP_MAC_ADMIN, then get the raw context
3398 	 * value even if it is not defined by current policy; otherwise,
3399 	 * use the in-core value under current policy.
3400 	 * Use the non-auditing forms of the permission checks since
3401 	 * getxattr may be called by unprivileged processes commonly
3402 	 * and lack of permission just means that we fall back to the
3403 	 * in-core context value, not a denial.
3404 	 */
3405 	isec = inode_security(inode);
3406 	if (has_cap_mac_admin(false))
3407 		error = security_sid_to_context_force(isec->sid, &context,
3408 						      &size);
3409 	else
3410 		error = security_sid_to_context(isec->sid,
3411 						&context, &size);
3412 	if (error)
3413 		return error;
3414 	error = size;
3415 	if (alloc) {
3416 		*buffer = context;
3417 		goto out_nofree;
3418 	}
3419 	kfree(context);
3420 out_nofree:
3421 	return error;
3422 }
3423 
3424 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3425 				     const void *value, size_t size, int flags)
3426 {
3427 	struct inode_security_struct *isec = inode_security_novalidate(inode);
3428 	struct superblock_security_struct *sbsec;
3429 	u32 newsid;
3430 	int rc;
3431 
3432 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
3433 		return -EOPNOTSUPP;
3434 
3435 	sbsec = selinux_superblock(inode->i_sb);
3436 	if (!(sbsec->flags & SBLABEL_MNT))
3437 		return -EOPNOTSUPP;
3438 
3439 	if (!value || !size)
3440 		return -EACCES;
3441 
3442 	rc = security_context_to_sid(value, size, &newsid,
3443 				     GFP_KERNEL);
3444 	if (rc)
3445 		return rc;
3446 
3447 	spin_lock(&isec->lock);
3448 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3449 	isec->sid = newsid;
3450 	isec->initialized = LABEL_INITIALIZED;
3451 	spin_unlock(&isec->lock);
3452 	return 0;
3453 }
3454 
3455 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3456 {
3457 	const int len = sizeof(XATTR_NAME_SELINUX);
3458 
3459 	if (!selinux_initialized())
3460 		return 0;
3461 
3462 	if (buffer && len <= buffer_size)
3463 		memcpy(buffer, XATTR_NAME_SELINUX, len);
3464 	return len;
3465 }
3466 
3467 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3468 {
3469 	struct inode_security_struct *isec = inode_security_novalidate(inode);
3470 	*secid = isec->sid;
3471 }
3472 
3473 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3474 {
3475 	u32 sid;
3476 	struct task_security_struct *tsec;
3477 	struct cred *new_creds = *new;
3478 
3479 	if (new_creds == NULL) {
3480 		new_creds = prepare_creds();
3481 		if (!new_creds)
3482 			return -ENOMEM;
3483 	}
3484 
3485 	tsec = selinux_cred(new_creds);
3486 	/* Get label from overlay inode and set it in create_sid */
3487 	selinux_inode_getsecid(d_inode(src), &sid);
3488 	tsec->create_sid = sid;
3489 	*new = new_creds;
3490 	return 0;
3491 }
3492 
3493 static int selinux_inode_copy_up_xattr(const char *name)
3494 {
3495 	/* The copy_up hook above sets the initial context on an inode, but we
3496 	 * don't then want to overwrite it by blindly copying all the lower
3497 	 * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3498 	 */
3499 	if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3500 		return 1; /* Discard */
3501 	/*
3502 	 * Any other attribute apart from SELINUX is not claimed, supported
3503 	 * by selinux.
3504 	 */
3505 	return -EOPNOTSUPP;
3506 }
3507 
3508 /* kernfs node operations */
3509 
3510 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3511 					struct kernfs_node *kn)
3512 {
3513 	const struct task_security_struct *tsec = selinux_cred(current_cred());
3514 	u32 parent_sid, newsid, clen;
3515 	int rc;
3516 	char *context;
3517 
3518 	rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3519 	if (rc == -ENODATA)
3520 		return 0;
3521 	else if (rc < 0)
3522 		return rc;
3523 
3524 	clen = (u32)rc;
3525 	context = kmalloc(clen, GFP_KERNEL);
3526 	if (!context)
3527 		return -ENOMEM;
3528 
3529 	rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3530 	if (rc < 0) {
3531 		kfree(context);
3532 		return rc;
3533 	}
3534 
3535 	rc = security_context_to_sid(context, clen, &parent_sid,
3536 				     GFP_KERNEL);
3537 	kfree(context);
3538 	if (rc)
3539 		return rc;
3540 
3541 	if (tsec->create_sid) {
3542 		newsid = tsec->create_sid;
3543 	} else {
3544 		u16 secclass = inode_mode_to_security_class(kn->mode);
3545 		struct qstr q;
3546 
3547 		q.name = kn->name;
3548 		q.hash_len = hashlen_string(kn_dir, kn->name);
3549 
3550 		rc = security_transition_sid(tsec->sid,
3551 					     parent_sid, secclass, &q,
3552 					     &newsid);
3553 		if (rc)
3554 			return rc;
3555 	}
3556 
3557 	rc = security_sid_to_context_force(newsid,
3558 					   &context, &clen);
3559 	if (rc)
3560 		return rc;
3561 
3562 	rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3563 			      XATTR_CREATE);
3564 	kfree(context);
3565 	return rc;
3566 }
3567 
3568 
3569 /* file security operations */
3570 
3571 static int selinux_revalidate_file_permission(struct file *file, int mask)
3572 {
3573 	const struct cred *cred = current_cred();
3574 	struct inode *inode = file_inode(file);
3575 
3576 	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3577 	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3578 		mask |= MAY_APPEND;
3579 
3580 	return file_has_perm(cred, file,
3581 			     file_mask_to_av(inode->i_mode, mask));
3582 }
3583 
3584 static int selinux_file_permission(struct file *file, int mask)
3585 {
3586 	struct inode *inode = file_inode(file);
3587 	struct file_security_struct *fsec = selinux_file(file);
3588 	struct inode_security_struct *isec;
3589 	u32 sid = current_sid();
3590 
3591 	if (!mask)
3592 		/* No permission to check.  Existence test. */
3593 		return 0;
3594 
3595 	isec = inode_security(inode);
3596 	if (sid == fsec->sid && fsec->isid == isec->sid &&
3597 	    fsec->pseqno == avc_policy_seqno())
3598 		/* No change since file_open check. */
3599 		return 0;
3600 
3601 	return selinux_revalidate_file_permission(file, mask);
3602 }
3603 
3604 static int selinux_file_alloc_security(struct file *file)
3605 {
3606 	struct file_security_struct *fsec = selinux_file(file);
3607 	u32 sid = current_sid();
3608 
3609 	fsec->sid = sid;
3610 	fsec->fown_sid = sid;
3611 
3612 	return 0;
3613 }
3614 
3615 /*
3616  * Check whether a task has the ioctl permission and cmd
3617  * operation to an inode.
3618  */
3619 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3620 		u32 requested, u16 cmd)
3621 {
3622 	struct common_audit_data ad;
3623 	struct file_security_struct *fsec = selinux_file(file);
3624 	struct inode *inode = file_inode(file);
3625 	struct inode_security_struct *isec;
3626 	struct lsm_ioctlop_audit ioctl;
3627 	u32 ssid = cred_sid(cred);
3628 	int rc;
3629 	u8 driver = cmd >> 8;
3630 	u8 xperm = cmd & 0xff;
3631 
3632 	ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3633 	ad.u.op = &ioctl;
3634 	ad.u.op->cmd = cmd;
3635 	ad.u.op->path = file->f_path;
3636 
3637 	if (ssid != fsec->sid) {
3638 		rc = avc_has_perm(ssid, fsec->sid,
3639 				SECCLASS_FD,
3640 				FD__USE,
3641 				&ad);
3642 		if (rc)
3643 			goto out;
3644 	}
3645 
3646 	if (unlikely(IS_PRIVATE(inode)))
3647 		return 0;
3648 
3649 	isec = inode_security(inode);
3650 	rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
3651 				    requested, driver, xperm, &ad);
3652 out:
3653 	return rc;
3654 }
3655 
3656 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3657 			      unsigned long arg)
3658 {
3659 	const struct cred *cred = current_cred();
3660 	int error = 0;
3661 
3662 	switch (cmd) {
3663 	case FIONREAD:
3664 	case FIBMAP:
3665 	case FIGETBSZ:
3666 	case FS_IOC_GETFLAGS:
3667 	case FS_IOC_GETVERSION:
3668 		error = file_has_perm(cred, file, FILE__GETATTR);
3669 		break;
3670 
3671 	case FS_IOC_SETFLAGS:
3672 	case FS_IOC_SETVERSION:
3673 		error = file_has_perm(cred, file, FILE__SETATTR);
3674 		break;
3675 
3676 	/* sys_ioctl() checks */
3677 	case FIONBIO:
3678 	case FIOASYNC:
3679 		error = file_has_perm(cred, file, 0);
3680 		break;
3681 
3682 	case KDSKBENT:
3683 	case KDSKBSENT:
3684 		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3685 					    CAP_OPT_NONE, true);
3686 		break;
3687 
3688 	case FIOCLEX:
3689 	case FIONCLEX:
3690 		if (!selinux_policycap_ioctl_skip_cloexec())
3691 			error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3692 		break;
3693 
3694 	/* default case assumes that the command will go
3695 	 * to the file's ioctl() function.
3696 	 */
3697 	default:
3698 		error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3699 	}
3700 	return error;
3701 }
3702 
3703 static int default_noexec __ro_after_init;
3704 
3705 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3706 {
3707 	const struct cred *cred = current_cred();
3708 	u32 sid = cred_sid(cred);
3709 	int rc = 0;
3710 
3711 	if (default_noexec &&
3712 	    (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3713 				   (!shared && (prot & PROT_WRITE)))) {
3714 		/*
3715 		 * We are making executable an anonymous mapping or a
3716 		 * private file mapping that will also be writable.
3717 		 * This has an additional check.
3718 		 */
3719 		rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3720 				  PROCESS__EXECMEM, NULL);
3721 		if (rc)
3722 			goto error;
3723 	}
3724 
3725 	if (file) {
3726 		/* read access is always possible with a mapping */
3727 		u32 av = FILE__READ;
3728 
3729 		/* write access only matters if the mapping is shared */
3730 		if (shared && (prot & PROT_WRITE))
3731 			av |= FILE__WRITE;
3732 
3733 		if (prot & PROT_EXEC)
3734 			av |= FILE__EXECUTE;
3735 
3736 		return file_has_perm(cred, file, av);
3737 	}
3738 
3739 error:
3740 	return rc;
3741 }
3742 
3743 static int selinux_mmap_addr(unsigned long addr)
3744 {
3745 	int rc = 0;
3746 
3747 	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3748 		u32 sid = current_sid();
3749 		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3750 				  MEMPROTECT__MMAP_ZERO, NULL);
3751 	}
3752 
3753 	return rc;
3754 }
3755 
3756 static int selinux_mmap_file(struct file *file,
3757 			     unsigned long reqprot __always_unused,
3758 			     unsigned long prot, unsigned long flags)
3759 {
3760 	struct common_audit_data ad;
3761 	int rc;
3762 
3763 	if (file) {
3764 		ad.type = LSM_AUDIT_DATA_FILE;
3765 		ad.u.file = file;
3766 		rc = inode_has_perm(current_cred(), file_inode(file),
3767 				    FILE__MAP, &ad);
3768 		if (rc)
3769 			return rc;
3770 	}
3771 
3772 	return file_map_prot_check(file, prot,
3773 				   (flags & MAP_TYPE) == MAP_SHARED);
3774 }
3775 
3776 static int selinux_file_mprotect(struct vm_area_struct *vma,
3777 				 unsigned long reqprot __always_unused,
3778 				 unsigned long prot)
3779 {
3780 	const struct cred *cred = current_cred();
3781 	u32 sid = cred_sid(cred);
3782 
3783 	if (default_noexec &&
3784 	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3785 		int rc = 0;
3786 		if (vma->vm_start >= vma->vm_mm->start_brk &&
3787 		    vma->vm_end <= vma->vm_mm->brk) {
3788 			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3789 					  PROCESS__EXECHEAP, NULL);
3790 		} else if (!vma->vm_file &&
3791 			   ((vma->vm_start <= vma->vm_mm->start_stack &&
3792 			     vma->vm_end >= vma->vm_mm->start_stack) ||
3793 			    vma_is_stack_for_current(vma))) {
3794 			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3795 					  PROCESS__EXECSTACK, NULL);
3796 		} else if (vma->vm_file && vma->anon_vma) {
3797 			/*
3798 			 * We are making executable a file mapping that has
3799 			 * had some COW done. Since pages might have been
3800 			 * written, check ability to execute the possibly
3801 			 * modified content.  This typically should only
3802 			 * occur for text relocations.
3803 			 */
3804 			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3805 		}
3806 		if (rc)
3807 			return rc;
3808 	}
3809 
3810 	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3811 }
3812 
3813 static int selinux_file_lock(struct file *file, unsigned int cmd)
3814 {
3815 	const struct cred *cred = current_cred();
3816 
3817 	return file_has_perm(cred, file, FILE__LOCK);
3818 }
3819 
3820 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3821 			      unsigned long arg)
3822 {
3823 	const struct cred *cred = current_cred();
3824 	int err = 0;
3825 
3826 	switch (cmd) {
3827 	case F_SETFL:
3828 		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3829 			err = file_has_perm(cred, file, FILE__WRITE);
3830 			break;
3831 		}
3832 		fallthrough;
3833 	case F_SETOWN:
3834 	case F_SETSIG:
3835 	case F_GETFL:
3836 	case F_GETOWN:
3837 	case F_GETSIG:
3838 	case F_GETOWNER_UIDS:
3839 		/* Just check FD__USE permission */
3840 		err = file_has_perm(cred, file, 0);
3841 		break;
3842 	case F_GETLK:
3843 	case F_SETLK:
3844 	case F_SETLKW:
3845 	case F_OFD_GETLK:
3846 	case F_OFD_SETLK:
3847 	case F_OFD_SETLKW:
3848 #if BITS_PER_LONG == 32
3849 	case F_GETLK64:
3850 	case F_SETLK64:
3851 	case F_SETLKW64:
3852 #endif
3853 		err = file_has_perm(cred, file, FILE__LOCK);
3854 		break;
3855 	}
3856 
3857 	return err;
3858 }
3859 
3860 static void selinux_file_set_fowner(struct file *file)
3861 {
3862 	struct file_security_struct *fsec;
3863 
3864 	fsec = selinux_file(file);
3865 	fsec->fown_sid = current_sid();
3866 }
3867 
3868 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3869 				       struct fown_struct *fown, int signum)
3870 {
3871 	struct file *file;
3872 	u32 sid = task_sid_obj(tsk);
3873 	u32 perm;
3874 	struct file_security_struct *fsec;
3875 
3876 	/* struct fown_struct is never outside the context of a struct file */
3877 	file = container_of(fown, struct file, f_owner);
3878 
3879 	fsec = selinux_file(file);
3880 
3881 	if (!signum)
3882 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3883 	else
3884 		perm = signal_to_av(signum);
3885 
3886 	return avc_has_perm(fsec->fown_sid, sid,
3887 			    SECCLASS_PROCESS, perm, NULL);
3888 }
3889 
3890 static int selinux_file_receive(struct file *file)
3891 {
3892 	const struct cred *cred = current_cred();
3893 
3894 	return file_has_perm(cred, file, file_to_av(file));
3895 }
3896 
3897 static int selinux_file_open(struct file *file)
3898 {
3899 	struct file_security_struct *fsec;
3900 	struct inode_security_struct *isec;
3901 
3902 	fsec = selinux_file(file);
3903 	isec = inode_security(file_inode(file));
3904 	/*
3905 	 * Save inode label and policy sequence number
3906 	 * at open-time so that selinux_file_permission
3907 	 * can determine whether revalidation is necessary.
3908 	 * Task label is already saved in the file security
3909 	 * struct as its SID.
3910 	 */
3911 	fsec->isid = isec->sid;
3912 	fsec->pseqno = avc_policy_seqno();
3913 	/*
3914 	 * Since the inode label or policy seqno may have changed
3915 	 * between the selinux_inode_permission check and the saving
3916 	 * of state above, recheck that access is still permitted.
3917 	 * Otherwise, access might never be revalidated against the
3918 	 * new inode label or new policy.
3919 	 * This check is not redundant - do not remove.
3920 	 */
3921 	return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3922 }
3923 
3924 /* task security operations */
3925 
3926 static int selinux_task_alloc(struct task_struct *task,
3927 			      unsigned long clone_flags)
3928 {
3929 	u32 sid = current_sid();
3930 
3931 	return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3932 }
3933 
3934 /*
3935  * prepare a new set of credentials for modification
3936  */
3937 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3938 				gfp_t gfp)
3939 {
3940 	const struct task_security_struct *old_tsec = selinux_cred(old);
3941 	struct task_security_struct *tsec = selinux_cred(new);
3942 
3943 	*tsec = *old_tsec;
3944 	return 0;
3945 }
3946 
3947 /*
3948  * transfer the SELinux data to a blank set of creds
3949  */
3950 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3951 {
3952 	const struct task_security_struct *old_tsec = selinux_cred(old);
3953 	struct task_security_struct *tsec = selinux_cred(new);
3954 
3955 	*tsec = *old_tsec;
3956 }
3957 
3958 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3959 {
3960 	*secid = cred_sid(c);
3961 }
3962 
3963 /*
3964  * set the security data for a kernel service
3965  * - all the creation contexts are set to unlabelled
3966  */
3967 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3968 {
3969 	struct task_security_struct *tsec = selinux_cred(new);
3970 	u32 sid = current_sid();
3971 	int ret;
3972 
3973 	ret = avc_has_perm(sid, secid,
3974 			   SECCLASS_KERNEL_SERVICE,
3975 			   KERNEL_SERVICE__USE_AS_OVERRIDE,
3976 			   NULL);
3977 	if (ret == 0) {
3978 		tsec->sid = secid;
3979 		tsec->create_sid = 0;
3980 		tsec->keycreate_sid = 0;
3981 		tsec->sockcreate_sid = 0;
3982 	}
3983 	return ret;
3984 }
3985 
3986 /*
3987  * set the file creation context in a security record to the same as the
3988  * objective context of the specified inode
3989  */
3990 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3991 {
3992 	struct inode_security_struct *isec = inode_security(inode);
3993 	struct task_security_struct *tsec = selinux_cred(new);
3994 	u32 sid = current_sid();
3995 	int ret;
3996 
3997 	ret = avc_has_perm(sid, isec->sid,
3998 			   SECCLASS_KERNEL_SERVICE,
3999 			   KERNEL_SERVICE__CREATE_FILES_AS,
4000 			   NULL);
4001 
4002 	if (ret == 0)
4003 		tsec->create_sid = isec->sid;
4004 	return ret;
4005 }
4006 
4007 static int selinux_kernel_module_request(char *kmod_name)
4008 {
4009 	struct common_audit_data ad;
4010 
4011 	ad.type = LSM_AUDIT_DATA_KMOD;
4012 	ad.u.kmod_name = kmod_name;
4013 
4014 	return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4015 			    SYSTEM__MODULE_REQUEST, &ad);
4016 }
4017 
4018 static int selinux_kernel_module_from_file(struct file *file)
4019 {
4020 	struct common_audit_data ad;
4021 	struct inode_security_struct *isec;
4022 	struct file_security_struct *fsec;
4023 	u32 sid = current_sid();
4024 	int rc;
4025 
4026 	/* init_module */
4027 	if (file == NULL)
4028 		return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
4029 					SYSTEM__MODULE_LOAD, NULL);
4030 
4031 	/* finit_module */
4032 
4033 	ad.type = LSM_AUDIT_DATA_FILE;
4034 	ad.u.file = file;
4035 
4036 	fsec = selinux_file(file);
4037 	if (sid != fsec->sid) {
4038 		rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4039 		if (rc)
4040 			return rc;
4041 	}
4042 
4043 	isec = inode_security(file_inode(file));
4044 	return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
4045 				SYSTEM__MODULE_LOAD, &ad);
4046 }
4047 
4048 static int selinux_kernel_read_file(struct file *file,
4049 				    enum kernel_read_file_id id,
4050 				    bool contents)
4051 {
4052 	int rc = 0;
4053 
4054 	switch (id) {
4055 	case READING_MODULE:
4056 		rc = selinux_kernel_module_from_file(contents ? file : NULL);
4057 		break;
4058 	default:
4059 		break;
4060 	}
4061 
4062 	return rc;
4063 }
4064 
4065 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4066 {
4067 	int rc = 0;
4068 
4069 	switch (id) {
4070 	case LOADING_MODULE:
4071 		rc = selinux_kernel_module_from_file(NULL);
4072 		break;
4073 	default:
4074 		break;
4075 	}
4076 
4077 	return rc;
4078 }
4079 
4080 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4081 {
4082 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4083 			    PROCESS__SETPGID, NULL);
4084 }
4085 
4086 static int selinux_task_getpgid(struct task_struct *p)
4087 {
4088 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4089 			    PROCESS__GETPGID, NULL);
4090 }
4091 
4092 static int selinux_task_getsid(struct task_struct *p)
4093 {
4094 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4095 			    PROCESS__GETSESSION, NULL);
4096 }
4097 
4098 static void selinux_current_getsecid_subj(u32 *secid)
4099 {
4100 	*secid = current_sid();
4101 }
4102 
4103 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid)
4104 {
4105 	*secid = task_sid_obj(p);
4106 }
4107 
4108 static int selinux_task_setnice(struct task_struct *p, int nice)
4109 {
4110 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4111 			    PROCESS__SETSCHED, NULL);
4112 }
4113 
4114 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4115 {
4116 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4117 			    PROCESS__SETSCHED, NULL);
4118 }
4119 
4120 static int selinux_task_getioprio(struct task_struct *p)
4121 {
4122 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4123 			    PROCESS__GETSCHED, NULL);
4124 }
4125 
4126 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4127 				unsigned int flags)
4128 {
4129 	u32 av = 0;
4130 
4131 	if (!flags)
4132 		return 0;
4133 	if (flags & LSM_PRLIMIT_WRITE)
4134 		av |= PROCESS__SETRLIMIT;
4135 	if (flags & LSM_PRLIMIT_READ)
4136 		av |= PROCESS__GETRLIMIT;
4137 	return avc_has_perm(cred_sid(cred), cred_sid(tcred),
4138 			    SECCLASS_PROCESS, av, NULL);
4139 }
4140 
4141 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4142 		struct rlimit *new_rlim)
4143 {
4144 	struct rlimit *old_rlim = p->signal->rlim + resource;
4145 
4146 	/* Control the ability to change the hard limit (whether
4147 	   lowering or raising it), so that the hard limit can
4148 	   later be used as a safe reset point for the soft limit
4149 	   upon context transitions.  See selinux_bprm_committing_creds. */
4150 	if (old_rlim->rlim_max != new_rlim->rlim_max)
4151 		return avc_has_perm(current_sid(), task_sid_obj(p),
4152 				    SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4153 
4154 	return 0;
4155 }
4156 
4157 static int selinux_task_setscheduler(struct task_struct *p)
4158 {
4159 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4160 			    PROCESS__SETSCHED, NULL);
4161 }
4162 
4163 static int selinux_task_getscheduler(struct task_struct *p)
4164 {
4165 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4166 			    PROCESS__GETSCHED, NULL);
4167 }
4168 
4169 static int selinux_task_movememory(struct task_struct *p)
4170 {
4171 	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4172 			    PROCESS__SETSCHED, NULL);
4173 }
4174 
4175 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4176 				int sig, const struct cred *cred)
4177 {
4178 	u32 secid;
4179 	u32 perm;
4180 
4181 	if (!sig)
4182 		perm = PROCESS__SIGNULL; /* null signal; existence test */
4183 	else
4184 		perm = signal_to_av(sig);
4185 	if (!cred)
4186 		secid = current_sid();
4187 	else
4188 		secid = cred_sid(cred);
4189 	return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4190 }
4191 
4192 static void selinux_task_to_inode(struct task_struct *p,
4193 				  struct inode *inode)
4194 {
4195 	struct inode_security_struct *isec = selinux_inode(inode);
4196 	u32 sid = task_sid_obj(p);
4197 
4198 	spin_lock(&isec->lock);
4199 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
4200 	isec->sid = sid;
4201 	isec->initialized = LABEL_INITIALIZED;
4202 	spin_unlock(&isec->lock);
4203 }
4204 
4205 static int selinux_userns_create(const struct cred *cred)
4206 {
4207 	u32 sid = current_sid();
4208 
4209 	return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4210 			USER_NAMESPACE__CREATE, NULL);
4211 }
4212 
4213 /* Returns error only if unable to parse addresses */
4214 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4215 			struct common_audit_data *ad, u8 *proto)
4216 {
4217 	int offset, ihlen, ret = -EINVAL;
4218 	struct iphdr _iph, *ih;
4219 
4220 	offset = skb_network_offset(skb);
4221 	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4222 	if (ih == NULL)
4223 		goto out;
4224 
4225 	ihlen = ih->ihl * 4;
4226 	if (ihlen < sizeof(_iph))
4227 		goto out;
4228 
4229 	ad->u.net->v4info.saddr = ih->saddr;
4230 	ad->u.net->v4info.daddr = ih->daddr;
4231 	ret = 0;
4232 
4233 	if (proto)
4234 		*proto = ih->protocol;
4235 
4236 	switch (ih->protocol) {
4237 	case IPPROTO_TCP: {
4238 		struct tcphdr _tcph, *th;
4239 
4240 		if (ntohs(ih->frag_off) & IP_OFFSET)
4241 			break;
4242 
4243 		offset += ihlen;
4244 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4245 		if (th == NULL)
4246 			break;
4247 
4248 		ad->u.net->sport = th->source;
4249 		ad->u.net->dport = th->dest;
4250 		break;
4251 	}
4252 
4253 	case IPPROTO_UDP: {
4254 		struct udphdr _udph, *uh;
4255 
4256 		if (ntohs(ih->frag_off) & IP_OFFSET)
4257 			break;
4258 
4259 		offset += ihlen;
4260 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4261 		if (uh == NULL)
4262 			break;
4263 
4264 		ad->u.net->sport = uh->source;
4265 		ad->u.net->dport = uh->dest;
4266 		break;
4267 	}
4268 
4269 	case IPPROTO_DCCP: {
4270 		struct dccp_hdr _dccph, *dh;
4271 
4272 		if (ntohs(ih->frag_off) & IP_OFFSET)
4273 			break;
4274 
4275 		offset += ihlen;
4276 		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4277 		if (dh == NULL)
4278 			break;
4279 
4280 		ad->u.net->sport = dh->dccph_sport;
4281 		ad->u.net->dport = dh->dccph_dport;
4282 		break;
4283 	}
4284 
4285 #if IS_ENABLED(CONFIG_IP_SCTP)
4286 	case IPPROTO_SCTP: {
4287 		struct sctphdr _sctph, *sh;
4288 
4289 		if (ntohs(ih->frag_off) & IP_OFFSET)
4290 			break;
4291 
4292 		offset += ihlen;
4293 		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4294 		if (sh == NULL)
4295 			break;
4296 
4297 		ad->u.net->sport = sh->source;
4298 		ad->u.net->dport = sh->dest;
4299 		break;
4300 	}
4301 #endif
4302 	default:
4303 		break;
4304 	}
4305 out:
4306 	return ret;
4307 }
4308 
4309 #if IS_ENABLED(CONFIG_IPV6)
4310 
4311 /* Returns error only if unable to parse addresses */
4312 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4313 			struct common_audit_data *ad, u8 *proto)
4314 {
4315 	u8 nexthdr;
4316 	int ret = -EINVAL, offset;
4317 	struct ipv6hdr _ipv6h, *ip6;
4318 	__be16 frag_off;
4319 
4320 	offset = skb_network_offset(skb);
4321 	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4322 	if (ip6 == NULL)
4323 		goto out;
4324 
4325 	ad->u.net->v6info.saddr = ip6->saddr;
4326 	ad->u.net->v6info.daddr = ip6->daddr;
4327 	ret = 0;
4328 
4329 	nexthdr = ip6->nexthdr;
4330 	offset += sizeof(_ipv6h);
4331 	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4332 	if (offset < 0)
4333 		goto out;
4334 
4335 	if (proto)
4336 		*proto = nexthdr;
4337 
4338 	switch (nexthdr) {
4339 	case IPPROTO_TCP: {
4340 		struct tcphdr _tcph, *th;
4341 
4342 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4343 		if (th == NULL)
4344 			break;
4345 
4346 		ad->u.net->sport = th->source;
4347 		ad->u.net->dport = th->dest;
4348 		break;
4349 	}
4350 
4351 	case IPPROTO_UDP: {
4352 		struct udphdr _udph, *uh;
4353 
4354 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4355 		if (uh == NULL)
4356 			break;
4357 
4358 		ad->u.net->sport = uh->source;
4359 		ad->u.net->dport = uh->dest;
4360 		break;
4361 	}
4362 
4363 	case IPPROTO_DCCP: {
4364 		struct dccp_hdr _dccph, *dh;
4365 
4366 		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4367 		if (dh == NULL)
4368 			break;
4369 
4370 		ad->u.net->sport = dh->dccph_sport;
4371 		ad->u.net->dport = dh->dccph_dport;
4372 		break;
4373 	}
4374 
4375 #if IS_ENABLED(CONFIG_IP_SCTP)
4376 	case IPPROTO_SCTP: {
4377 		struct sctphdr _sctph, *sh;
4378 
4379 		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4380 		if (sh == NULL)
4381 			break;
4382 
4383 		ad->u.net->sport = sh->source;
4384 		ad->u.net->dport = sh->dest;
4385 		break;
4386 	}
4387 #endif
4388 	/* includes fragments */
4389 	default:
4390 		break;
4391 	}
4392 out:
4393 	return ret;
4394 }
4395 
4396 #endif /* IPV6 */
4397 
4398 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4399 			     char **_addrp, int src, u8 *proto)
4400 {
4401 	char *addrp;
4402 	int ret;
4403 
4404 	switch (ad->u.net->family) {
4405 	case PF_INET:
4406 		ret = selinux_parse_skb_ipv4(skb, ad, proto);
4407 		if (ret)
4408 			goto parse_error;
4409 		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4410 				       &ad->u.net->v4info.daddr);
4411 		goto okay;
4412 
4413 #if IS_ENABLED(CONFIG_IPV6)
4414 	case PF_INET6:
4415 		ret = selinux_parse_skb_ipv6(skb, ad, proto);
4416 		if (ret)
4417 			goto parse_error;
4418 		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4419 				       &ad->u.net->v6info.daddr);
4420 		goto okay;
4421 #endif	/* IPV6 */
4422 	default:
4423 		addrp = NULL;
4424 		goto okay;
4425 	}
4426 
4427 parse_error:
4428 	pr_warn(
4429 	       "SELinux: failure in selinux_parse_skb(),"
4430 	       " unable to parse packet\n");
4431 	return ret;
4432 
4433 okay:
4434 	if (_addrp)
4435 		*_addrp = addrp;
4436 	return 0;
4437 }
4438 
4439 /**
4440  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4441  * @skb: the packet
4442  * @family: protocol family
4443  * @sid: the packet's peer label SID
4444  *
4445  * Description:
4446  * Check the various different forms of network peer labeling and determine
4447  * the peer label/SID for the packet; most of the magic actually occurs in
4448  * the security server function security_net_peersid_cmp().  The function
4449  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4450  * or -EACCES if @sid is invalid due to inconsistencies with the different
4451  * peer labels.
4452  *
4453  */
4454 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4455 {
4456 	int err;
4457 	u32 xfrm_sid;
4458 	u32 nlbl_sid;
4459 	u32 nlbl_type;
4460 
4461 	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4462 	if (unlikely(err))
4463 		return -EACCES;
4464 	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4465 	if (unlikely(err))
4466 		return -EACCES;
4467 
4468 	err = security_net_peersid_resolve(nlbl_sid,
4469 					   nlbl_type, xfrm_sid, sid);
4470 	if (unlikely(err)) {
4471 		pr_warn(
4472 		       "SELinux: failure in selinux_skb_peerlbl_sid(),"
4473 		       " unable to determine packet's peer label\n");
4474 		return -EACCES;
4475 	}
4476 
4477 	return 0;
4478 }
4479 
4480 /**
4481  * selinux_conn_sid - Determine the child socket label for a connection
4482  * @sk_sid: the parent socket's SID
4483  * @skb_sid: the packet's SID
4484  * @conn_sid: the resulting connection SID
4485  *
4486  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4487  * combined with the MLS information from @skb_sid in order to create
4488  * @conn_sid.  If @skb_sid is not valid then @conn_sid is simply a copy
4489  * of @sk_sid.  Returns zero on success, negative values on failure.
4490  *
4491  */
4492 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4493 {
4494 	int err = 0;
4495 
4496 	if (skb_sid != SECSID_NULL)
4497 		err = security_sid_mls_copy(sk_sid, skb_sid,
4498 					    conn_sid);
4499 	else
4500 		*conn_sid = sk_sid;
4501 
4502 	return err;
4503 }
4504 
4505 /* socket security operations */
4506 
4507 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4508 				 u16 secclass, u32 *socksid)
4509 {
4510 	if (tsec->sockcreate_sid > SECSID_NULL) {
4511 		*socksid = tsec->sockcreate_sid;
4512 		return 0;
4513 	}
4514 
4515 	return security_transition_sid(tsec->sid, tsec->sid,
4516 				       secclass, NULL, socksid);
4517 }
4518 
4519 static int sock_has_perm(struct sock *sk, u32 perms)
4520 {
4521 	struct sk_security_struct *sksec = sk->sk_security;
4522 	struct common_audit_data ad;
4523 	struct lsm_network_audit net = {0,};
4524 
4525 	if (sksec->sid == SECINITSID_KERNEL)
4526 		return 0;
4527 
4528 	ad.type = LSM_AUDIT_DATA_NET;
4529 	ad.u.net = &net;
4530 	ad.u.net->sk = sk;
4531 
4532 	return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
4533 			    &ad);
4534 }
4535 
4536 static int selinux_socket_create(int family, int type,
4537 				 int protocol, int kern)
4538 {
4539 	const struct task_security_struct *tsec = selinux_cred(current_cred());
4540 	u32 newsid;
4541 	u16 secclass;
4542 	int rc;
4543 
4544 	if (kern)
4545 		return 0;
4546 
4547 	secclass = socket_type_to_security_class(family, type, protocol);
4548 	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4549 	if (rc)
4550 		return rc;
4551 
4552 	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4553 }
4554 
4555 static int selinux_socket_post_create(struct socket *sock, int family,
4556 				      int type, int protocol, int kern)
4557 {
4558 	const struct task_security_struct *tsec = selinux_cred(current_cred());
4559 	struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4560 	struct sk_security_struct *sksec;
4561 	u16 sclass = socket_type_to_security_class(family, type, protocol);
4562 	u32 sid = SECINITSID_KERNEL;
4563 	int err = 0;
4564 
4565 	if (!kern) {
4566 		err = socket_sockcreate_sid(tsec, sclass, &sid);
4567 		if (err)
4568 			return err;
4569 	}
4570 
4571 	isec->sclass = sclass;
4572 	isec->sid = sid;
4573 	isec->initialized = LABEL_INITIALIZED;
4574 
4575 	if (sock->sk) {
4576 		sksec = sock->sk->sk_security;
4577 		sksec->sclass = sclass;
4578 		sksec->sid = sid;
4579 		/* Allows detection of the first association on this socket */
4580 		if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4581 			sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4582 
4583 		err = selinux_netlbl_socket_post_create(sock->sk, family);
4584 	}
4585 
4586 	return err;
4587 }
4588 
4589 static int selinux_socket_socketpair(struct socket *socka,
4590 				     struct socket *sockb)
4591 {
4592 	struct sk_security_struct *sksec_a = socka->sk->sk_security;
4593 	struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4594 
4595 	sksec_a->peer_sid = sksec_b->sid;
4596 	sksec_b->peer_sid = sksec_a->sid;
4597 
4598 	return 0;
4599 }
4600 
4601 /* Range of port numbers used to automatically bind.
4602    Need to determine whether we should perform a name_bind
4603    permission check between the socket and the port number. */
4604 
4605 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4606 {
4607 	struct sock *sk = sock->sk;
4608 	struct sk_security_struct *sksec = sk->sk_security;
4609 	u16 family;
4610 	int err;
4611 
4612 	err = sock_has_perm(sk, SOCKET__BIND);
4613 	if (err)
4614 		goto out;
4615 
4616 	/* If PF_INET or PF_INET6, check name_bind permission for the port. */
4617 	family = sk->sk_family;
4618 	if (family == PF_INET || family == PF_INET6) {
4619 		char *addrp;
4620 		struct common_audit_data ad;
4621 		struct lsm_network_audit net = {0,};
4622 		struct sockaddr_in *addr4 = NULL;
4623 		struct sockaddr_in6 *addr6 = NULL;
4624 		u16 family_sa;
4625 		unsigned short snum;
4626 		u32 sid, node_perm;
4627 
4628 		/*
4629 		 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4630 		 * that validates multiple binding addresses. Because of this
4631 		 * need to check address->sa_family as it is possible to have
4632 		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4633 		 */
4634 		if (addrlen < offsetofend(struct sockaddr, sa_family))
4635 			return -EINVAL;
4636 		family_sa = address->sa_family;
4637 		switch (family_sa) {
4638 		case AF_UNSPEC:
4639 		case AF_INET:
4640 			if (addrlen < sizeof(struct sockaddr_in))
4641 				return -EINVAL;
4642 			addr4 = (struct sockaddr_in *)address;
4643 			if (family_sa == AF_UNSPEC) {
4644 				/* see __inet_bind(), we only want to allow
4645 				 * AF_UNSPEC if the address is INADDR_ANY
4646 				 */
4647 				if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4648 					goto err_af;
4649 				family_sa = AF_INET;
4650 			}
4651 			snum = ntohs(addr4->sin_port);
4652 			addrp = (char *)&addr4->sin_addr.s_addr;
4653 			break;
4654 		case AF_INET6:
4655 			if (addrlen < SIN6_LEN_RFC2133)
4656 				return -EINVAL;
4657 			addr6 = (struct sockaddr_in6 *)address;
4658 			snum = ntohs(addr6->sin6_port);
4659 			addrp = (char *)&addr6->sin6_addr.s6_addr;
4660 			break;
4661 		default:
4662 			goto err_af;
4663 		}
4664 
4665 		ad.type = LSM_AUDIT_DATA_NET;
4666 		ad.u.net = &net;
4667 		ad.u.net->sport = htons(snum);
4668 		ad.u.net->family = family_sa;
4669 
4670 		if (snum) {
4671 			int low, high;
4672 
4673 			inet_get_local_port_range(sock_net(sk), &low, &high);
4674 
4675 			if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4676 			    snum < low || snum > high) {
4677 				err = sel_netport_sid(sk->sk_protocol,
4678 						      snum, &sid);
4679 				if (err)
4680 					goto out;
4681 				err = avc_has_perm(sksec->sid, sid,
4682 						   sksec->sclass,
4683 						   SOCKET__NAME_BIND, &ad);
4684 				if (err)
4685 					goto out;
4686 			}
4687 		}
4688 
4689 		switch (sksec->sclass) {
4690 		case SECCLASS_TCP_SOCKET:
4691 			node_perm = TCP_SOCKET__NODE_BIND;
4692 			break;
4693 
4694 		case SECCLASS_UDP_SOCKET:
4695 			node_perm = UDP_SOCKET__NODE_BIND;
4696 			break;
4697 
4698 		case SECCLASS_DCCP_SOCKET:
4699 			node_perm = DCCP_SOCKET__NODE_BIND;
4700 			break;
4701 
4702 		case SECCLASS_SCTP_SOCKET:
4703 			node_perm = SCTP_SOCKET__NODE_BIND;
4704 			break;
4705 
4706 		default:
4707 			node_perm = RAWIP_SOCKET__NODE_BIND;
4708 			break;
4709 		}
4710 
4711 		err = sel_netnode_sid(addrp, family_sa, &sid);
4712 		if (err)
4713 			goto out;
4714 
4715 		if (family_sa == AF_INET)
4716 			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4717 		else
4718 			ad.u.net->v6info.saddr = addr6->sin6_addr;
4719 
4720 		err = avc_has_perm(sksec->sid, sid,
4721 				   sksec->sclass, node_perm, &ad);
4722 		if (err)
4723 			goto out;
4724 	}
4725 out:
4726 	return err;
4727 err_af:
4728 	/* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4729 	if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4730 		return -EINVAL;
4731 	return -EAFNOSUPPORT;
4732 }
4733 
4734 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4735  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4736  */
4737 static int selinux_socket_connect_helper(struct socket *sock,
4738 					 struct sockaddr *address, int addrlen)
4739 {
4740 	struct sock *sk = sock->sk;
4741 	struct sk_security_struct *sksec = sk->sk_security;
4742 	int err;
4743 
4744 	err = sock_has_perm(sk, SOCKET__CONNECT);
4745 	if (err)
4746 		return err;
4747 	if (addrlen < offsetofend(struct sockaddr, sa_family))
4748 		return -EINVAL;
4749 
4750 	/* connect(AF_UNSPEC) has special handling, as it is a documented
4751 	 * way to disconnect the socket
4752 	 */
4753 	if (address->sa_family == AF_UNSPEC)
4754 		return 0;
4755 
4756 	/*
4757 	 * If a TCP, DCCP or SCTP socket, check name_connect permission
4758 	 * for the port.
4759 	 */
4760 	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4761 	    sksec->sclass == SECCLASS_DCCP_SOCKET ||
4762 	    sksec->sclass == SECCLASS_SCTP_SOCKET) {
4763 		struct common_audit_data ad;
4764 		struct lsm_network_audit net = {0,};
4765 		struct sockaddr_in *addr4 = NULL;
4766 		struct sockaddr_in6 *addr6 = NULL;
4767 		unsigned short snum;
4768 		u32 sid, perm;
4769 
4770 		/* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4771 		 * that validates multiple connect addresses. Because of this
4772 		 * need to check address->sa_family as it is possible to have
4773 		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4774 		 */
4775 		switch (address->sa_family) {
4776 		case AF_INET:
4777 			addr4 = (struct sockaddr_in *)address;
4778 			if (addrlen < sizeof(struct sockaddr_in))
4779 				return -EINVAL;
4780 			snum = ntohs(addr4->sin_port);
4781 			break;
4782 		case AF_INET6:
4783 			addr6 = (struct sockaddr_in6 *)address;
4784 			if (addrlen < SIN6_LEN_RFC2133)
4785 				return -EINVAL;
4786 			snum = ntohs(addr6->sin6_port);
4787 			break;
4788 		default:
4789 			/* Note that SCTP services expect -EINVAL, whereas
4790 			 * others expect -EAFNOSUPPORT.
4791 			 */
4792 			if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4793 				return -EINVAL;
4794 			else
4795 				return -EAFNOSUPPORT;
4796 		}
4797 
4798 		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4799 		if (err)
4800 			return err;
4801 
4802 		switch (sksec->sclass) {
4803 		case SECCLASS_TCP_SOCKET:
4804 			perm = TCP_SOCKET__NAME_CONNECT;
4805 			break;
4806 		case SECCLASS_DCCP_SOCKET:
4807 			perm = DCCP_SOCKET__NAME_CONNECT;
4808 			break;
4809 		case SECCLASS_SCTP_SOCKET:
4810 			perm = SCTP_SOCKET__NAME_CONNECT;
4811 			break;
4812 		}
4813 
4814 		ad.type = LSM_AUDIT_DATA_NET;
4815 		ad.u.net = &net;
4816 		ad.u.net->dport = htons(snum);
4817 		ad.u.net->family = address->sa_family;
4818 		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4819 		if (err)
4820 			return err;
4821 	}
4822 
4823 	return 0;
4824 }
4825 
4826 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4827 static int selinux_socket_connect(struct socket *sock,
4828 				  struct sockaddr *address, int addrlen)
4829 {
4830 	int err;
4831 	struct sock *sk = sock->sk;
4832 
4833 	err = selinux_socket_connect_helper(sock, address, addrlen);
4834 	if (err)
4835 		return err;
4836 
4837 	return selinux_netlbl_socket_connect(sk, address);
4838 }
4839 
4840 static int selinux_socket_listen(struct socket *sock, int backlog)
4841 {
4842 	return sock_has_perm(sock->sk, SOCKET__LISTEN);
4843 }
4844 
4845 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4846 {
4847 	int err;
4848 	struct inode_security_struct *isec;
4849 	struct inode_security_struct *newisec;
4850 	u16 sclass;
4851 	u32 sid;
4852 
4853 	err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4854 	if (err)
4855 		return err;
4856 
4857 	isec = inode_security_novalidate(SOCK_INODE(sock));
4858 	spin_lock(&isec->lock);
4859 	sclass = isec->sclass;
4860 	sid = isec->sid;
4861 	spin_unlock(&isec->lock);
4862 
4863 	newisec = inode_security_novalidate(SOCK_INODE(newsock));
4864 	newisec->sclass = sclass;
4865 	newisec->sid = sid;
4866 	newisec->initialized = LABEL_INITIALIZED;
4867 
4868 	return 0;
4869 }
4870 
4871 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4872 				  int size)
4873 {
4874 	return sock_has_perm(sock->sk, SOCKET__WRITE);
4875 }
4876 
4877 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4878 				  int size, int flags)
4879 {
4880 	return sock_has_perm(sock->sk, SOCKET__READ);
4881 }
4882 
4883 static int selinux_socket_getsockname(struct socket *sock)
4884 {
4885 	return sock_has_perm(sock->sk, SOCKET__GETATTR);
4886 }
4887 
4888 static int selinux_socket_getpeername(struct socket *sock)
4889 {
4890 	return sock_has_perm(sock->sk, SOCKET__GETATTR);
4891 }
4892 
4893 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4894 {
4895 	int err;
4896 
4897 	err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4898 	if (err)
4899 		return err;
4900 
4901 	return selinux_netlbl_socket_setsockopt(sock, level, optname);
4902 }
4903 
4904 static int selinux_socket_getsockopt(struct socket *sock, int level,
4905 				     int optname)
4906 {
4907 	return sock_has_perm(sock->sk, SOCKET__GETOPT);
4908 }
4909 
4910 static int selinux_socket_shutdown(struct socket *sock, int how)
4911 {
4912 	return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4913 }
4914 
4915 static int selinux_socket_unix_stream_connect(struct sock *sock,
4916 					      struct sock *other,
4917 					      struct sock *newsk)
4918 {
4919 	struct sk_security_struct *sksec_sock = sock->sk_security;
4920 	struct sk_security_struct *sksec_other = other->sk_security;
4921 	struct sk_security_struct *sksec_new = newsk->sk_security;
4922 	struct common_audit_data ad;
4923 	struct lsm_network_audit net = {0,};
4924 	int err;
4925 
4926 	ad.type = LSM_AUDIT_DATA_NET;
4927 	ad.u.net = &net;
4928 	ad.u.net->sk = other;
4929 
4930 	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4931 			   sksec_other->sclass,
4932 			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4933 	if (err)
4934 		return err;
4935 
4936 	/* server child socket */
4937 	sksec_new->peer_sid = sksec_sock->sid;
4938 	err = security_sid_mls_copy(sksec_other->sid,
4939 				    sksec_sock->sid, &sksec_new->sid);
4940 	if (err)
4941 		return err;
4942 
4943 	/* connecting socket */
4944 	sksec_sock->peer_sid = sksec_new->sid;
4945 
4946 	return 0;
4947 }
4948 
4949 static int selinux_socket_unix_may_send(struct socket *sock,
4950 					struct socket *other)
4951 {
4952 	struct sk_security_struct *ssec = sock->sk->sk_security;
4953 	struct sk_security_struct *osec = other->sk->sk_security;
4954 	struct common_audit_data ad;
4955 	struct lsm_network_audit net = {0,};
4956 
4957 	ad.type = LSM_AUDIT_DATA_NET;
4958 	ad.u.net = &net;
4959 	ad.u.net->sk = other->sk;
4960 
4961 	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4962 			    &ad);
4963 }
4964 
4965 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4966 				    char *addrp, u16 family, u32 peer_sid,
4967 				    struct common_audit_data *ad)
4968 {
4969 	int err;
4970 	u32 if_sid;
4971 	u32 node_sid;
4972 
4973 	err = sel_netif_sid(ns, ifindex, &if_sid);
4974 	if (err)
4975 		return err;
4976 	err = avc_has_perm(peer_sid, if_sid,
4977 			   SECCLASS_NETIF, NETIF__INGRESS, ad);
4978 	if (err)
4979 		return err;
4980 
4981 	err = sel_netnode_sid(addrp, family, &node_sid);
4982 	if (err)
4983 		return err;
4984 	return avc_has_perm(peer_sid, node_sid,
4985 			    SECCLASS_NODE, NODE__RECVFROM, ad);
4986 }
4987 
4988 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4989 				       u16 family)
4990 {
4991 	int err = 0;
4992 	struct sk_security_struct *sksec = sk->sk_security;
4993 	u32 sk_sid = sksec->sid;
4994 	struct common_audit_data ad;
4995 	struct lsm_network_audit net = {0,};
4996 	char *addrp;
4997 
4998 	ad.type = LSM_AUDIT_DATA_NET;
4999 	ad.u.net = &net;
5000 	ad.u.net->netif = skb->skb_iif;
5001 	ad.u.net->family = family;
5002 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5003 	if (err)
5004 		return err;
5005 
5006 	if (selinux_secmark_enabled()) {
5007 		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5008 				   PACKET__RECV, &ad);
5009 		if (err)
5010 			return err;
5011 	}
5012 
5013 	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5014 	if (err)
5015 		return err;
5016 	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5017 
5018 	return err;
5019 }
5020 
5021 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5022 {
5023 	int err;
5024 	struct sk_security_struct *sksec = sk->sk_security;
5025 	u16 family = sk->sk_family;
5026 	u32 sk_sid = sksec->sid;
5027 	struct common_audit_data ad;
5028 	struct lsm_network_audit net = {0,};
5029 	char *addrp;
5030 	u8 secmark_active;
5031 	u8 peerlbl_active;
5032 
5033 	if (family != PF_INET && family != PF_INET6)
5034 		return 0;
5035 
5036 	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
5037 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5038 		family = PF_INET;
5039 
5040 	/* If any sort of compatibility mode is enabled then handoff processing
5041 	 * to the selinux_sock_rcv_skb_compat() function to deal with the
5042 	 * special handling.  We do this in an attempt to keep this function
5043 	 * as fast and as clean as possible. */
5044 	if (!selinux_policycap_netpeer())
5045 		return selinux_sock_rcv_skb_compat(sk, skb, family);
5046 
5047 	secmark_active = selinux_secmark_enabled();
5048 	peerlbl_active = selinux_peerlbl_enabled();
5049 	if (!secmark_active && !peerlbl_active)
5050 		return 0;
5051 
5052 	ad.type = LSM_AUDIT_DATA_NET;
5053 	ad.u.net = &net;
5054 	ad.u.net->netif = skb->skb_iif;
5055 	ad.u.net->family = family;
5056 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5057 	if (err)
5058 		return err;
5059 
5060 	if (peerlbl_active) {
5061 		u32 peer_sid;
5062 
5063 		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5064 		if (err)
5065 			return err;
5066 		err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5067 					       addrp, family, peer_sid, &ad);
5068 		if (err) {
5069 			selinux_netlbl_err(skb, family, err, 0);
5070 			return err;
5071 		}
5072 		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
5073 				   PEER__RECV, &ad);
5074 		if (err) {
5075 			selinux_netlbl_err(skb, family, err, 0);
5076 			return err;
5077 		}
5078 	}
5079 
5080 	if (secmark_active) {
5081 		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5082 				   PACKET__RECV, &ad);
5083 		if (err)
5084 			return err;
5085 	}
5086 
5087 	return err;
5088 }
5089 
5090 static int selinux_socket_getpeersec_stream(struct socket *sock,
5091 					    sockptr_t optval, sockptr_t optlen,
5092 					    unsigned int len)
5093 {
5094 	int err = 0;
5095 	char *scontext = NULL;
5096 	u32 scontext_len;
5097 	struct sk_security_struct *sksec = sock->sk->sk_security;
5098 	u32 peer_sid = SECSID_NULL;
5099 
5100 	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5101 	    sksec->sclass == SECCLASS_TCP_SOCKET ||
5102 	    sksec->sclass == SECCLASS_SCTP_SOCKET)
5103 		peer_sid = sksec->peer_sid;
5104 	if (peer_sid == SECSID_NULL)
5105 		return -ENOPROTOOPT;
5106 
5107 	err = security_sid_to_context(peer_sid, &scontext,
5108 				      &scontext_len);
5109 	if (err)
5110 		return err;
5111 	if (scontext_len > len) {
5112 		err = -ERANGE;
5113 		goto out_len;
5114 	}
5115 
5116 	if (copy_to_sockptr(optval, scontext, scontext_len))
5117 		err = -EFAULT;
5118 out_len:
5119 	if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5120 		err = -EFAULT;
5121 	kfree(scontext);
5122 	return err;
5123 }
5124 
5125 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5126 {
5127 	u32 peer_secid = SECSID_NULL;
5128 	u16 family;
5129 	struct inode_security_struct *isec;
5130 
5131 	if (skb && skb->protocol == htons(ETH_P_IP))
5132 		family = PF_INET;
5133 	else if (skb && skb->protocol == htons(ETH_P_IPV6))
5134 		family = PF_INET6;
5135 	else if (sock)
5136 		family = sock->sk->sk_family;
5137 	else
5138 		goto out;
5139 
5140 	if (sock && family == PF_UNIX) {
5141 		isec = inode_security_novalidate(SOCK_INODE(sock));
5142 		peer_secid = isec->sid;
5143 	} else if (skb)
5144 		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5145 
5146 out:
5147 	*secid = peer_secid;
5148 	if (peer_secid == SECSID_NULL)
5149 		return -EINVAL;
5150 	return 0;
5151 }
5152 
5153 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5154 {
5155 	struct sk_security_struct *sksec;
5156 
5157 	sksec = kzalloc(sizeof(*sksec), priority);
5158 	if (!sksec)
5159 		return -ENOMEM;
5160 
5161 	sksec->peer_sid = SECINITSID_UNLABELED;
5162 	sksec->sid = SECINITSID_UNLABELED;
5163 	sksec->sclass = SECCLASS_SOCKET;
5164 	selinux_netlbl_sk_security_reset(sksec);
5165 	sk->sk_security = sksec;
5166 
5167 	return 0;
5168 }
5169 
5170 static void selinux_sk_free_security(struct sock *sk)
5171 {
5172 	struct sk_security_struct *sksec = sk->sk_security;
5173 
5174 	sk->sk_security = NULL;
5175 	selinux_netlbl_sk_security_free(sksec);
5176 	kfree(sksec);
5177 }
5178 
5179 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5180 {
5181 	struct sk_security_struct *sksec = sk->sk_security;
5182 	struct sk_security_struct *newsksec = newsk->sk_security;
5183 
5184 	newsksec->sid = sksec->sid;
5185 	newsksec->peer_sid = sksec->peer_sid;
5186 	newsksec->sclass = sksec->sclass;
5187 
5188 	selinux_netlbl_sk_security_reset(newsksec);
5189 }
5190 
5191 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5192 {
5193 	if (!sk)
5194 		*secid = SECINITSID_ANY_SOCKET;
5195 	else {
5196 		struct sk_security_struct *sksec = sk->sk_security;
5197 
5198 		*secid = sksec->sid;
5199 	}
5200 }
5201 
5202 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5203 {
5204 	struct inode_security_struct *isec =
5205 		inode_security_novalidate(SOCK_INODE(parent));
5206 	struct sk_security_struct *sksec = sk->sk_security;
5207 
5208 	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5209 	    sk->sk_family == PF_UNIX)
5210 		isec->sid = sksec->sid;
5211 	sksec->sclass = isec->sclass;
5212 }
5213 
5214 /*
5215  * Determines peer_secid for the asoc and updates socket's peer label
5216  * if it's the first association on the socket.
5217  */
5218 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5219 					  struct sk_buff *skb)
5220 {
5221 	struct sock *sk = asoc->base.sk;
5222 	u16 family = sk->sk_family;
5223 	struct sk_security_struct *sksec = sk->sk_security;
5224 	struct common_audit_data ad;
5225 	struct lsm_network_audit net = {0,};
5226 	int err;
5227 
5228 	/* handle mapped IPv4 packets arriving via IPv6 sockets */
5229 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5230 		family = PF_INET;
5231 
5232 	if (selinux_peerlbl_enabled()) {
5233 		asoc->peer_secid = SECSID_NULL;
5234 
5235 		/* This will return peer_sid = SECSID_NULL if there are
5236 		 * no peer labels, see security_net_peersid_resolve().
5237 		 */
5238 		err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5239 		if (err)
5240 			return err;
5241 
5242 		if (asoc->peer_secid == SECSID_NULL)
5243 			asoc->peer_secid = SECINITSID_UNLABELED;
5244 	} else {
5245 		asoc->peer_secid = SECINITSID_UNLABELED;
5246 	}
5247 
5248 	if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5249 		sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5250 
5251 		/* Here as first association on socket. As the peer SID
5252 		 * was allowed by peer recv (and the netif/node checks),
5253 		 * then it is approved by policy and used as the primary
5254 		 * peer SID for getpeercon(3).
5255 		 */
5256 		sksec->peer_sid = asoc->peer_secid;
5257 	} else if (sksec->peer_sid != asoc->peer_secid) {
5258 		/* Other association peer SIDs are checked to enforce
5259 		 * consistency among the peer SIDs.
5260 		 */
5261 		ad.type = LSM_AUDIT_DATA_NET;
5262 		ad.u.net = &net;
5263 		ad.u.net->sk = asoc->base.sk;
5264 		err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5265 				   sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5266 				   &ad);
5267 		if (err)
5268 			return err;
5269 	}
5270 	return 0;
5271 }
5272 
5273 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5274  * happens on an incoming connect(2), sctp_connectx(3) or
5275  * sctp_sendmsg(3) (with no association already present).
5276  */
5277 static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5278 				      struct sk_buff *skb)
5279 {
5280 	struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5281 	u32 conn_sid;
5282 	int err;
5283 
5284 	if (!selinux_policycap_extsockclass())
5285 		return 0;
5286 
5287 	err = selinux_sctp_process_new_assoc(asoc, skb);
5288 	if (err)
5289 		return err;
5290 
5291 	/* Compute the MLS component for the connection and store
5292 	 * the information in asoc. This will be used by SCTP TCP type
5293 	 * sockets and peeled off connections as they cause a new
5294 	 * socket to be generated. selinux_sctp_sk_clone() will then
5295 	 * plug this into the new socket.
5296 	 */
5297 	err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5298 	if (err)
5299 		return err;
5300 
5301 	asoc->secid = conn_sid;
5302 
5303 	/* Set any NetLabel labels including CIPSO/CALIPSO options. */
5304 	return selinux_netlbl_sctp_assoc_request(asoc, skb);
5305 }
5306 
5307 /* Called when SCTP receives a COOKIE ACK chunk as the final
5308  * response to an association request (initited by us).
5309  */
5310 static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5311 					  struct sk_buff *skb)
5312 {
5313 	struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5314 
5315 	if (!selinux_policycap_extsockclass())
5316 		return 0;
5317 
5318 	/* Inherit secid from the parent socket - this will be picked up
5319 	 * by selinux_sctp_sk_clone() if the association gets peeled off
5320 	 * into a new socket.
5321 	 */
5322 	asoc->secid = sksec->sid;
5323 
5324 	return selinux_sctp_process_new_assoc(asoc, skb);
5325 }
5326 
5327 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5328  * based on their @optname.
5329  */
5330 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5331 				     struct sockaddr *address,
5332 				     int addrlen)
5333 {
5334 	int len, err = 0, walk_size = 0;
5335 	void *addr_buf;
5336 	struct sockaddr *addr;
5337 	struct socket *sock;
5338 
5339 	if (!selinux_policycap_extsockclass())
5340 		return 0;
5341 
5342 	/* Process one or more addresses that may be IPv4 or IPv6 */
5343 	sock = sk->sk_socket;
5344 	addr_buf = address;
5345 
5346 	while (walk_size < addrlen) {
5347 		if (walk_size + sizeof(sa_family_t) > addrlen)
5348 			return -EINVAL;
5349 
5350 		addr = addr_buf;
5351 		switch (addr->sa_family) {
5352 		case AF_UNSPEC:
5353 		case AF_INET:
5354 			len = sizeof(struct sockaddr_in);
5355 			break;
5356 		case AF_INET6:
5357 			len = sizeof(struct sockaddr_in6);
5358 			break;
5359 		default:
5360 			return -EINVAL;
5361 		}
5362 
5363 		if (walk_size + len > addrlen)
5364 			return -EINVAL;
5365 
5366 		err = -EINVAL;
5367 		switch (optname) {
5368 		/* Bind checks */
5369 		case SCTP_PRIMARY_ADDR:
5370 		case SCTP_SET_PEER_PRIMARY_ADDR:
5371 		case SCTP_SOCKOPT_BINDX_ADD:
5372 			err = selinux_socket_bind(sock, addr, len);
5373 			break;
5374 		/* Connect checks */
5375 		case SCTP_SOCKOPT_CONNECTX:
5376 		case SCTP_PARAM_SET_PRIMARY:
5377 		case SCTP_PARAM_ADD_IP:
5378 		case SCTP_SENDMSG_CONNECT:
5379 			err = selinux_socket_connect_helper(sock, addr, len);
5380 			if (err)
5381 				return err;
5382 
5383 			/* As selinux_sctp_bind_connect() is called by the
5384 			 * SCTP protocol layer, the socket is already locked,
5385 			 * therefore selinux_netlbl_socket_connect_locked()
5386 			 * is called here. The situations handled are:
5387 			 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5388 			 * whenever a new IP address is added or when a new
5389 			 * primary address is selected.
5390 			 * Note that an SCTP connect(2) call happens before
5391 			 * the SCTP protocol layer and is handled via
5392 			 * selinux_socket_connect().
5393 			 */
5394 			err = selinux_netlbl_socket_connect_locked(sk, addr);
5395 			break;
5396 		}
5397 
5398 		if (err)
5399 			return err;
5400 
5401 		addr_buf += len;
5402 		walk_size += len;
5403 	}
5404 
5405 	return 0;
5406 }
5407 
5408 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5409 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5410 				  struct sock *newsk)
5411 {
5412 	struct sk_security_struct *sksec = sk->sk_security;
5413 	struct sk_security_struct *newsksec = newsk->sk_security;
5414 
5415 	/* If policy does not support SECCLASS_SCTP_SOCKET then call
5416 	 * the non-sctp clone version.
5417 	 */
5418 	if (!selinux_policycap_extsockclass())
5419 		return selinux_sk_clone_security(sk, newsk);
5420 
5421 	newsksec->sid = asoc->secid;
5422 	newsksec->peer_sid = asoc->peer_secid;
5423 	newsksec->sclass = sksec->sclass;
5424 	selinux_netlbl_sctp_sk_clone(sk, newsk);
5425 }
5426 
5427 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5428 {
5429 	struct sk_security_struct *ssksec = ssk->sk_security;
5430 	struct sk_security_struct *sksec = sk->sk_security;
5431 
5432 	ssksec->sclass = sksec->sclass;
5433 	ssksec->sid = sksec->sid;
5434 
5435 	/* replace the existing subflow label deleting the existing one
5436 	 * and re-recreating a new label using the updated context
5437 	 */
5438 	selinux_netlbl_sk_security_free(ssksec);
5439 	return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5440 }
5441 
5442 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5443 				     struct request_sock *req)
5444 {
5445 	struct sk_security_struct *sksec = sk->sk_security;
5446 	int err;
5447 	u16 family = req->rsk_ops->family;
5448 	u32 connsid;
5449 	u32 peersid;
5450 
5451 	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5452 	if (err)
5453 		return err;
5454 	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5455 	if (err)
5456 		return err;
5457 	req->secid = connsid;
5458 	req->peer_secid = peersid;
5459 
5460 	return selinux_netlbl_inet_conn_request(req, family);
5461 }
5462 
5463 static void selinux_inet_csk_clone(struct sock *newsk,
5464 				   const struct request_sock *req)
5465 {
5466 	struct sk_security_struct *newsksec = newsk->sk_security;
5467 
5468 	newsksec->sid = req->secid;
5469 	newsksec->peer_sid = req->peer_secid;
5470 	/* NOTE: Ideally, we should also get the isec->sid for the
5471 	   new socket in sync, but we don't have the isec available yet.
5472 	   So we will wait until sock_graft to do it, by which
5473 	   time it will have been created and available. */
5474 
5475 	/* We don't need to take any sort of lock here as we are the only
5476 	 * thread with access to newsksec */
5477 	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5478 }
5479 
5480 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5481 {
5482 	u16 family = sk->sk_family;
5483 	struct sk_security_struct *sksec = sk->sk_security;
5484 
5485 	/* handle mapped IPv4 packets arriving via IPv6 sockets */
5486 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5487 		family = PF_INET;
5488 
5489 	selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5490 }
5491 
5492 static int selinux_secmark_relabel_packet(u32 sid)
5493 {
5494 	const struct task_security_struct *__tsec;
5495 	u32 tsid;
5496 
5497 	__tsec = selinux_cred(current_cred());
5498 	tsid = __tsec->sid;
5499 
5500 	return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5501 			    NULL);
5502 }
5503 
5504 static void selinux_secmark_refcount_inc(void)
5505 {
5506 	atomic_inc(&selinux_secmark_refcount);
5507 }
5508 
5509 static void selinux_secmark_refcount_dec(void)
5510 {
5511 	atomic_dec(&selinux_secmark_refcount);
5512 }
5513 
5514 static void selinux_req_classify_flow(const struct request_sock *req,
5515 				      struct flowi_common *flic)
5516 {
5517 	flic->flowic_secid = req->secid;
5518 }
5519 
5520 static int selinux_tun_dev_alloc_security(void **security)
5521 {
5522 	struct tun_security_struct *tunsec;
5523 
5524 	tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5525 	if (!tunsec)
5526 		return -ENOMEM;
5527 	tunsec->sid = current_sid();
5528 
5529 	*security = tunsec;
5530 	return 0;
5531 }
5532 
5533 static void selinux_tun_dev_free_security(void *security)
5534 {
5535 	kfree(security);
5536 }
5537 
5538 static int selinux_tun_dev_create(void)
5539 {
5540 	u32 sid = current_sid();
5541 
5542 	/* we aren't taking into account the "sockcreate" SID since the socket
5543 	 * that is being created here is not a socket in the traditional sense,
5544 	 * instead it is a private sock, accessible only to the kernel, and
5545 	 * representing a wide range of network traffic spanning multiple
5546 	 * connections unlike traditional sockets - check the TUN driver to
5547 	 * get a better understanding of why this socket is special */
5548 
5549 	return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5550 			    NULL);
5551 }
5552 
5553 static int selinux_tun_dev_attach_queue(void *security)
5554 {
5555 	struct tun_security_struct *tunsec = security;
5556 
5557 	return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5558 			    TUN_SOCKET__ATTACH_QUEUE, NULL);
5559 }
5560 
5561 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5562 {
5563 	struct tun_security_struct *tunsec = security;
5564 	struct sk_security_struct *sksec = sk->sk_security;
5565 
5566 	/* we don't currently perform any NetLabel based labeling here and it
5567 	 * isn't clear that we would want to do so anyway; while we could apply
5568 	 * labeling without the support of the TUN user the resulting labeled
5569 	 * traffic from the other end of the connection would almost certainly
5570 	 * cause confusion to the TUN user that had no idea network labeling
5571 	 * protocols were being used */
5572 
5573 	sksec->sid = tunsec->sid;
5574 	sksec->sclass = SECCLASS_TUN_SOCKET;
5575 
5576 	return 0;
5577 }
5578 
5579 static int selinux_tun_dev_open(void *security)
5580 {
5581 	struct tun_security_struct *tunsec = security;
5582 	u32 sid = current_sid();
5583 	int err;
5584 
5585 	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5586 			   TUN_SOCKET__RELABELFROM, NULL);
5587 	if (err)
5588 		return err;
5589 	err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5590 			   TUN_SOCKET__RELABELTO, NULL);
5591 	if (err)
5592 		return err;
5593 	tunsec->sid = sid;
5594 
5595 	return 0;
5596 }
5597 
5598 #ifdef CONFIG_NETFILTER
5599 
5600 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5601 				       const struct nf_hook_state *state)
5602 {
5603 	int ifindex;
5604 	u16 family;
5605 	char *addrp;
5606 	u32 peer_sid;
5607 	struct common_audit_data ad;
5608 	struct lsm_network_audit net = {0,};
5609 	int secmark_active, peerlbl_active;
5610 
5611 	if (!selinux_policycap_netpeer())
5612 		return NF_ACCEPT;
5613 
5614 	secmark_active = selinux_secmark_enabled();
5615 	peerlbl_active = selinux_peerlbl_enabled();
5616 	if (!secmark_active && !peerlbl_active)
5617 		return NF_ACCEPT;
5618 
5619 	family = state->pf;
5620 	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5621 		return NF_DROP;
5622 
5623 	ifindex = state->in->ifindex;
5624 	ad.type = LSM_AUDIT_DATA_NET;
5625 	ad.u.net = &net;
5626 	ad.u.net->netif = ifindex;
5627 	ad.u.net->family = family;
5628 	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5629 		return NF_DROP;
5630 
5631 	if (peerlbl_active) {
5632 		int err;
5633 
5634 		err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5635 					       addrp, family, peer_sid, &ad);
5636 		if (err) {
5637 			selinux_netlbl_err(skb, family, err, 1);
5638 			return NF_DROP;
5639 		}
5640 	}
5641 
5642 	if (secmark_active)
5643 		if (avc_has_perm(peer_sid, skb->secmark,
5644 				 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5645 			return NF_DROP;
5646 
5647 	if (netlbl_enabled())
5648 		/* we do this in the FORWARD path and not the POST_ROUTING
5649 		 * path because we want to make sure we apply the necessary
5650 		 * labeling before IPsec is applied so we can leverage AH
5651 		 * protection */
5652 		if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5653 			return NF_DROP;
5654 
5655 	return NF_ACCEPT;
5656 }
5657 
5658 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5659 				      const struct nf_hook_state *state)
5660 {
5661 	struct sock *sk;
5662 	u32 sid;
5663 
5664 	if (!netlbl_enabled())
5665 		return NF_ACCEPT;
5666 
5667 	/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5668 	 * because we want to make sure we apply the necessary labeling
5669 	 * before IPsec is applied so we can leverage AH protection */
5670 	sk = skb->sk;
5671 	if (sk) {
5672 		struct sk_security_struct *sksec;
5673 
5674 		if (sk_listener(sk))
5675 			/* if the socket is the listening state then this
5676 			 * packet is a SYN-ACK packet which means it needs to
5677 			 * be labeled based on the connection/request_sock and
5678 			 * not the parent socket.  unfortunately, we can't
5679 			 * lookup the request_sock yet as it isn't queued on
5680 			 * the parent socket until after the SYN-ACK is sent.
5681 			 * the "solution" is to simply pass the packet as-is
5682 			 * as any IP option based labeling should be copied
5683 			 * from the initial connection request (in the IP
5684 			 * layer).  it is far from ideal, but until we get a
5685 			 * security label in the packet itself this is the
5686 			 * best we can do. */
5687 			return NF_ACCEPT;
5688 
5689 		/* standard practice, label using the parent socket */
5690 		sksec = sk->sk_security;
5691 		sid = sksec->sid;
5692 	} else
5693 		sid = SECINITSID_KERNEL;
5694 	if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5695 		return NF_DROP;
5696 
5697 	return NF_ACCEPT;
5698 }
5699 
5700 
5701 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5702 					const struct nf_hook_state *state)
5703 {
5704 	struct sock *sk;
5705 	struct sk_security_struct *sksec;
5706 	struct common_audit_data ad;
5707 	struct lsm_network_audit net = {0,};
5708 	u8 proto = 0;
5709 
5710 	sk = skb_to_full_sk(skb);
5711 	if (sk == NULL)
5712 		return NF_ACCEPT;
5713 	sksec = sk->sk_security;
5714 
5715 	ad.type = LSM_AUDIT_DATA_NET;
5716 	ad.u.net = &net;
5717 	ad.u.net->netif = state->out->ifindex;
5718 	ad.u.net->family = state->pf;
5719 	if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5720 		return NF_DROP;
5721 
5722 	if (selinux_secmark_enabled())
5723 		if (avc_has_perm(sksec->sid, skb->secmark,
5724 				 SECCLASS_PACKET, PACKET__SEND, &ad))
5725 			return NF_DROP_ERR(-ECONNREFUSED);
5726 
5727 	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5728 		return NF_DROP_ERR(-ECONNREFUSED);
5729 
5730 	return NF_ACCEPT;
5731 }
5732 
5733 static unsigned int selinux_ip_postroute(void *priv,
5734 					 struct sk_buff *skb,
5735 					 const struct nf_hook_state *state)
5736 {
5737 	u16 family;
5738 	u32 secmark_perm;
5739 	u32 peer_sid;
5740 	int ifindex;
5741 	struct sock *sk;
5742 	struct common_audit_data ad;
5743 	struct lsm_network_audit net = {0,};
5744 	char *addrp;
5745 	int secmark_active, peerlbl_active;
5746 
5747 	/* If any sort of compatibility mode is enabled then handoff processing
5748 	 * to the selinux_ip_postroute_compat() function to deal with the
5749 	 * special handling.  We do this in an attempt to keep this function
5750 	 * as fast and as clean as possible. */
5751 	if (!selinux_policycap_netpeer())
5752 		return selinux_ip_postroute_compat(skb, state);
5753 
5754 	secmark_active = selinux_secmark_enabled();
5755 	peerlbl_active = selinux_peerlbl_enabled();
5756 	if (!secmark_active && !peerlbl_active)
5757 		return NF_ACCEPT;
5758 
5759 	sk = skb_to_full_sk(skb);
5760 
5761 #ifdef CONFIG_XFRM
5762 	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5763 	 * packet transformation so allow the packet to pass without any checks
5764 	 * since we'll have another chance to perform access control checks
5765 	 * when the packet is on it's final way out.
5766 	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5767 	 *       is NULL, in this case go ahead and apply access control.
5768 	 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5769 	 *       TCP listening state we cannot wait until the XFRM processing
5770 	 *       is done as we will miss out on the SA label if we do;
5771 	 *       unfortunately, this means more work, but it is only once per
5772 	 *       connection. */
5773 	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5774 	    !(sk && sk_listener(sk)))
5775 		return NF_ACCEPT;
5776 #endif
5777 
5778 	family = state->pf;
5779 	if (sk == NULL) {
5780 		/* Without an associated socket the packet is either coming
5781 		 * from the kernel or it is being forwarded; check the packet
5782 		 * to determine which and if the packet is being forwarded
5783 		 * query the packet directly to determine the security label. */
5784 		if (skb->skb_iif) {
5785 			secmark_perm = PACKET__FORWARD_OUT;
5786 			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5787 				return NF_DROP;
5788 		} else {
5789 			secmark_perm = PACKET__SEND;
5790 			peer_sid = SECINITSID_KERNEL;
5791 		}
5792 	} else if (sk_listener(sk)) {
5793 		/* Locally generated packet but the associated socket is in the
5794 		 * listening state which means this is a SYN-ACK packet.  In
5795 		 * this particular case the correct security label is assigned
5796 		 * to the connection/request_sock but unfortunately we can't
5797 		 * query the request_sock as it isn't queued on the parent
5798 		 * socket until after the SYN-ACK packet is sent; the only
5799 		 * viable choice is to regenerate the label like we do in
5800 		 * selinux_inet_conn_request().  See also selinux_ip_output()
5801 		 * for similar problems. */
5802 		u32 skb_sid;
5803 		struct sk_security_struct *sksec;
5804 
5805 		sksec = sk->sk_security;
5806 		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5807 			return NF_DROP;
5808 		/* At this point, if the returned skb peerlbl is SECSID_NULL
5809 		 * and the packet has been through at least one XFRM
5810 		 * transformation then we must be dealing with the "final"
5811 		 * form of labeled IPsec packet; since we've already applied
5812 		 * all of our access controls on this packet we can safely
5813 		 * pass the packet. */
5814 		if (skb_sid == SECSID_NULL) {
5815 			switch (family) {
5816 			case PF_INET:
5817 				if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5818 					return NF_ACCEPT;
5819 				break;
5820 			case PF_INET6:
5821 				if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5822 					return NF_ACCEPT;
5823 				break;
5824 			default:
5825 				return NF_DROP_ERR(-ECONNREFUSED);
5826 			}
5827 		}
5828 		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5829 			return NF_DROP;
5830 		secmark_perm = PACKET__SEND;
5831 	} else {
5832 		/* Locally generated packet, fetch the security label from the
5833 		 * associated socket. */
5834 		struct sk_security_struct *sksec = sk->sk_security;
5835 		peer_sid = sksec->sid;
5836 		secmark_perm = PACKET__SEND;
5837 	}
5838 
5839 	ifindex = state->out->ifindex;
5840 	ad.type = LSM_AUDIT_DATA_NET;
5841 	ad.u.net = &net;
5842 	ad.u.net->netif = ifindex;
5843 	ad.u.net->family = family;
5844 	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5845 		return NF_DROP;
5846 
5847 	if (secmark_active)
5848 		if (avc_has_perm(peer_sid, skb->secmark,
5849 				 SECCLASS_PACKET, secmark_perm, &ad))
5850 			return NF_DROP_ERR(-ECONNREFUSED);
5851 
5852 	if (peerlbl_active) {
5853 		u32 if_sid;
5854 		u32 node_sid;
5855 
5856 		if (sel_netif_sid(state->net, ifindex, &if_sid))
5857 			return NF_DROP;
5858 		if (avc_has_perm(peer_sid, if_sid,
5859 				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5860 			return NF_DROP_ERR(-ECONNREFUSED);
5861 
5862 		if (sel_netnode_sid(addrp, family, &node_sid))
5863 			return NF_DROP;
5864 		if (avc_has_perm(peer_sid, node_sid,
5865 				 SECCLASS_NODE, NODE__SENDTO, &ad))
5866 			return NF_DROP_ERR(-ECONNREFUSED);
5867 	}
5868 
5869 	return NF_ACCEPT;
5870 }
5871 #endif	/* CONFIG_NETFILTER */
5872 
5873 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5874 {
5875 	int rc = 0;
5876 	unsigned int msg_len;
5877 	unsigned int data_len = skb->len;
5878 	unsigned char *data = skb->data;
5879 	struct nlmsghdr *nlh;
5880 	struct sk_security_struct *sksec = sk->sk_security;
5881 	u16 sclass = sksec->sclass;
5882 	u32 perm;
5883 
5884 	while (data_len >= nlmsg_total_size(0)) {
5885 		nlh = (struct nlmsghdr *)data;
5886 
5887 		/* NOTE: the nlmsg_len field isn't reliably set by some netlink
5888 		 *       users which means we can't reject skb's with bogus
5889 		 *       length fields; our solution is to follow what
5890 		 *       netlink_rcv_skb() does and simply skip processing at
5891 		 *       messages with length fields that are clearly junk
5892 		 */
5893 		if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5894 			return 0;
5895 
5896 		rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5897 		if (rc == 0) {
5898 			rc = sock_has_perm(sk, perm);
5899 			if (rc)
5900 				return rc;
5901 		} else if (rc == -EINVAL) {
5902 			/* -EINVAL is a missing msg/perm mapping */
5903 			pr_warn_ratelimited("SELinux: unrecognized netlink"
5904 				" message: protocol=%hu nlmsg_type=%hu sclass=%s"
5905 				" pid=%d comm=%s\n",
5906 				sk->sk_protocol, nlh->nlmsg_type,
5907 				secclass_map[sclass - 1].name,
5908 				task_pid_nr(current), current->comm);
5909 			if (enforcing_enabled() &&
5910 			    !security_get_allow_unknown())
5911 				return rc;
5912 			rc = 0;
5913 		} else if (rc == -ENOENT) {
5914 			/* -ENOENT is a missing socket/class mapping, ignore */
5915 			rc = 0;
5916 		} else {
5917 			return rc;
5918 		}
5919 
5920 		/* move to the next message after applying netlink padding */
5921 		msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
5922 		if (msg_len >= data_len)
5923 			return 0;
5924 		data_len -= msg_len;
5925 		data += msg_len;
5926 	}
5927 
5928 	return rc;
5929 }
5930 
5931 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5932 {
5933 	isec->sclass = sclass;
5934 	isec->sid = current_sid();
5935 }
5936 
5937 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5938 			u32 perms)
5939 {
5940 	struct ipc_security_struct *isec;
5941 	struct common_audit_data ad;
5942 	u32 sid = current_sid();
5943 
5944 	isec = selinux_ipc(ipc_perms);
5945 
5946 	ad.type = LSM_AUDIT_DATA_IPC;
5947 	ad.u.ipc_id = ipc_perms->key;
5948 
5949 	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5950 }
5951 
5952 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5953 {
5954 	struct msg_security_struct *msec;
5955 
5956 	msec = selinux_msg_msg(msg);
5957 	msec->sid = SECINITSID_UNLABELED;
5958 
5959 	return 0;
5960 }
5961 
5962 /* message queue security operations */
5963 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5964 {
5965 	struct ipc_security_struct *isec;
5966 	struct common_audit_data ad;
5967 	u32 sid = current_sid();
5968 
5969 	isec = selinux_ipc(msq);
5970 	ipc_init_security(isec, SECCLASS_MSGQ);
5971 
5972 	ad.type = LSM_AUDIT_DATA_IPC;
5973 	ad.u.ipc_id = msq->key;
5974 
5975 	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5976 			    MSGQ__CREATE, &ad);
5977 }
5978 
5979 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
5980 {
5981 	struct ipc_security_struct *isec;
5982 	struct common_audit_data ad;
5983 	u32 sid = current_sid();
5984 
5985 	isec = selinux_ipc(msq);
5986 
5987 	ad.type = LSM_AUDIT_DATA_IPC;
5988 	ad.u.ipc_id = msq->key;
5989 
5990 	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5991 			    MSGQ__ASSOCIATE, &ad);
5992 }
5993 
5994 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
5995 {
5996 	int err;
5997 	int perms;
5998 
5999 	switch (cmd) {
6000 	case IPC_INFO:
6001 	case MSG_INFO:
6002 		/* No specific object, just general system-wide information. */
6003 		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6004 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6005 	case IPC_STAT:
6006 	case MSG_STAT:
6007 	case MSG_STAT_ANY:
6008 		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6009 		break;
6010 	case IPC_SET:
6011 		perms = MSGQ__SETATTR;
6012 		break;
6013 	case IPC_RMID:
6014 		perms = MSGQ__DESTROY;
6015 		break;
6016 	default:
6017 		return 0;
6018 	}
6019 
6020 	err = ipc_has_perm(msq, perms);
6021 	return err;
6022 }
6023 
6024 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6025 {
6026 	struct ipc_security_struct *isec;
6027 	struct msg_security_struct *msec;
6028 	struct common_audit_data ad;
6029 	u32 sid = current_sid();
6030 	int rc;
6031 
6032 	isec = selinux_ipc(msq);
6033 	msec = selinux_msg_msg(msg);
6034 
6035 	/*
6036 	 * First time through, need to assign label to the message
6037 	 */
6038 	if (msec->sid == SECINITSID_UNLABELED) {
6039 		/*
6040 		 * Compute new sid based on current process and
6041 		 * message queue this message will be stored in
6042 		 */
6043 		rc = security_transition_sid(sid, isec->sid,
6044 					     SECCLASS_MSG, NULL, &msec->sid);
6045 		if (rc)
6046 			return rc;
6047 	}
6048 
6049 	ad.type = LSM_AUDIT_DATA_IPC;
6050 	ad.u.ipc_id = msq->key;
6051 
6052 	/* Can this process write to the queue? */
6053 	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6054 			  MSGQ__WRITE, &ad);
6055 	if (!rc)
6056 		/* Can this process send the message */
6057 		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
6058 				  MSG__SEND, &ad);
6059 	if (!rc)
6060 		/* Can the message be put in the queue? */
6061 		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
6062 				  MSGQ__ENQUEUE, &ad);
6063 
6064 	return rc;
6065 }
6066 
6067 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6068 				    struct task_struct *target,
6069 				    long type, int mode)
6070 {
6071 	struct ipc_security_struct *isec;
6072 	struct msg_security_struct *msec;
6073 	struct common_audit_data ad;
6074 	u32 sid = task_sid_obj(target);
6075 	int rc;
6076 
6077 	isec = selinux_ipc(msq);
6078 	msec = selinux_msg_msg(msg);
6079 
6080 	ad.type = LSM_AUDIT_DATA_IPC;
6081 	ad.u.ipc_id = msq->key;
6082 
6083 	rc = avc_has_perm(sid, isec->sid,
6084 			  SECCLASS_MSGQ, MSGQ__READ, &ad);
6085 	if (!rc)
6086 		rc = avc_has_perm(sid, msec->sid,
6087 				  SECCLASS_MSG, MSG__RECEIVE, &ad);
6088 	return rc;
6089 }
6090 
6091 /* Shared Memory security operations */
6092 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6093 {
6094 	struct ipc_security_struct *isec;
6095 	struct common_audit_data ad;
6096 	u32 sid = current_sid();
6097 
6098 	isec = selinux_ipc(shp);
6099 	ipc_init_security(isec, SECCLASS_SHM);
6100 
6101 	ad.type = LSM_AUDIT_DATA_IPC;
6102 	ad.u.ipc_id = shp->key;
6103 
6104 	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6105 			    SHM__CREATE, &ad);
6106 }
6107 
6108 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6109 {
6110 	struct ipc_security_struct *isec;
6111 	struct common_audit_data ad;
6112 	u32 sid = current_sid();
6113 
6114 	isec = selinux_ipc(shp);
6115 
6116 	ad.type = LSM_AUDIT_DATA_IPC;
6117 	ad.u.ipc_id = shp->key;
6118 
6119 	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6120 			    SHM__ASSOCIATE, &ad);
6121 }
6122 
6123 /* Note, at this point, shp is locked down */
6124 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6125 {
6126 	int perms;
6127 	int err;
6128 
6129 	switch (cmd) {
6130 	case IPC_INFO:
6131 	case SHM_INFO:
6132 		/* No specific object, just general system-wide information. */
6133 		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6134 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6135 	case IPC_STAT:
6136 	case SHM_STAT:
6137 	case SHM_STAT_ANY:
6138 		perms = SHM__GETATTR | SHM__ASSOCIATE;
6139 		break;
6140 	case IPC_SET:
6141 		perms = SHM__SETATTR;
6142 		break;
6143 	case SHM_LOCK:
6144 	case SHM_UNLOCK:
6145 		perms = SHM__LOCK;
6146 		break;
6147 	case IPC_RMID:
6148 		perms = SHM__DESTROY;
6149 		break;
6150 	default:
6151 		return 0;
6152 	}
6153 
6154 	err = ipc_has_perm(shp, perms);
6155 	return err;
6156 }
6157 
6158 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6159 			     char __user *shmaddr, int shmflg)
6160 {
6161 	u32 perms;
6162 
6163 	if (shmflg & SHM_RDONLY)
6164 		perms = SHM__READ;
6165 	else
6166 		perms = SHM__READ | SHM__WRITE;
6167 
6168 	return ipc_has_perm(shp, perms);
6169 }
6170 
6171 /* Semaphore security operations */
6172 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6173 {
6174 	struct ipc_security_struct *isec;
6175 	struct common_audit_data ad;
6176 	u32 sid = current_sid();
6177 
6178 	isec = selinux_ipc(sma);
6179 	ipc_init_security(isec, SECCLASS_SEM);
6180 
6181 	ad.type = LSM_AUDIT_DATA_IPC;
6182 	ad.u.ipc_id = sma->key;
6183 
6184 	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6185 			    SEM__CREATE, &ad);
6186 }
6187 
6188 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6189 {
6190 	struct ipc_security_struct *isec;
6191 	struct common_audit_data ad;
6192 	u32 sid = current_sid();
6193 
6194 	isec = selinux_ipc(sma);
6195 
6196 	ad.type = LSM_AUDIT_DATA_IPC;
6197 	ad.u.ipc_id = sma->key;
6198 
6199 	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6200 			    SEM__ASSOCIATE, &ad);
6201 }
6202 
6203 /* Note, at this point, sma is locked down */
6204 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6205 {
6206 	int err;
6207 	u32 perms;
6208 
6209 	switch (cmd) {
6210 	case IPC_INFO:
6211 	case SEM_INFO:
6212 		/* No specific object, just general system-wide information. */
6213 		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6214 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6215 	case GETPID:
6216 	case GETNCNT:
6217 	case GETZCNT:
6218 		perms = SEM__GETATTR;
6219 		break;
6220 	case GETVAL:
6221 	case GETALL:
6222 		perms = SEM__READ;
6223 		break;
6224 	case SETVAL:
6225 	case SETALL:
6226 		perms = SEM__WRITE;
6227 		break;
6228 	case IPC_RMID:
6229 		perms = SEM__DESTROY;
6230 		break;
6231 	case IPC_SET:
6232 		perms = SEM__SETATTR;
6233 		break;
6234 	case IPC_STAT:
6235 	case SEM_STAT:
6236 	case SEM_STAT_ANY:
6237 		perms = SEM__GETATTR | SEM__ASSOCIATE;
6238 		break;
6239 	default:
6240 		return 0;
6241 	}
6242 
6243 	err = ipc_has_perm(sma, perms);
6244 	return err;
6245 }
6246 
6247 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6248 			     struct sembuf *sops, unsigned nsops, int alter)
6249 {
6250 	u32 perms;
6251 
6252 	if (alter)
6253 		perms = SEM__READ | SEM__WRITE;
6254 	else
6255 		perms = SEM__READ;
6256 
6257 	return ipc_has_perm(sma, perms);
6258 }
6259 
6260 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6261 {
6262 	u32 av = 0;
6263 
6264 	av = 0;
6265 	if (flag & S_IRUGO)
6266 		av |= IPC__UNIX_READ;
6267 	if (flag & S_IWUGO)
6268 		av |= IPC__UNIX_WRITE;
6269 
6270 	if (av == 0)
6271 		return 0;
6272 
6273 	return ipc_has_perm(ipcp, av);
6274 }
6275 
6276 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6277 {
6278 	struct ipc_security_struct *isec = selinux_ipc(ipcp);
6279 	*secid = isec->sid;
6280 }
6281 
6282 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6283 {
6284 	if (inode)
6285 		inode_doinit_with_dentry(inode, dentry);
6286 }
6287 
6288 static int selinux_getprocattr(struct task_struct *p,
6289 			       const char *name, char **value)
6290 {
6291 	const struct task_security_struct *__tsec;
6292 	u32 sid;
6293 	int error;
6294 	unsigned len;
6295 
6296 	rcu_read_lock();
6297 	__tsec = selinux_cred(__task_cred(p));
6298 
6299 	if (current != p) {
6300 		error = avc_has_perm(current_sid(), __tsec->sid,
6301 				     SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6302 		if (error)
6303 			goto bad;
6304 	}
6305 
6306 	if (!strcmp(name, "current"))
6307 		sid = __tsec->sid;
6308 	else if (!strcmp(name, "prev"))
6309 		sid = __tsec->osid;
6310 	else if (!strcmp(name, "exec"))
6311 		sid = __tsec->exec_sid;
6312 	else if (!strcmp(name, "fscreate"))
6313 		sid = __tsec->create_sid;
6314 	else if (!strcmp(name, "keycreate"))
6315 		sid = __tsec->keycreate_sid;
6316 	else if (!strcmp(name, "sockcreate"))
6317 		sid = __tsec->sockcreate_sid;
6318 	else {
6319 		error = -EINVAL;
6320 		goto bad;
6321 	}
6322 	rcu_read_unlock();
6323 
6324 	if (!sid)
6325 		return 0;
6326 
6327 	error = security_sid_to_context(sid, value, &len);
6328 	if (error)
6329 		return error;
6330 	return len;
6331 
6332 bad:
6333 	rcu_read_unlock();
6334 	return error;
6335 }
6336 
6337 static int selinux_setprocattr(const char *name, void *value, size_t size)
6338 {
6339 	struct task_security_struct *tsec;
6340 	struct cred *new;
6341 	u32 mysid = current_sid(), sid = 0, ptsid;
6342 	int error;
6343 	char *str = value;
6344 
6345 	/*
6346 	 * Basic control over ability to set these attributes at all.
6347 	 */
6348 	if (!strcmp(name, "exec"))
6349 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6350 				     PROCESS__SETEXEC, NULL);
6351 	else if (!strcmp(name, "fscreate"))
6352 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6353 				     PROCESS__SETFSCREATE, NULL);
6354 	else if (!strcmp(name, "keycreate"))
6355 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6356 				     PROCESS__SETKEYCREATE, NULL);
6357 	else if (!strcmp(name, "sockcreate"))
6358 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6359 				     PROCESS__SETSOCKCREATE, NULL);
6360 	else if (!strcmp(name, "current"))
6361 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6362 				     PROCESS__SETCURRENT, NULL);
6363 	else
6364 		error = -EINVAL;
6365 	if (error)
6366 		return error;
6367 
6368 	/* Obtain a SID for the context, if one was specified. */
6369 	if (size && str[0] && str[0] != '\n') {
6370 		if (str[size-1] == '\n') {
6371 			str[size-1] = 0;
6372 			size--;
6373 		}
6374 		error = security_context_to_sid(value, size,
6375 						&sid, GFP_KERNEL);
6376 		if (error == -EINVAL && !strcmp(name, "fscreate")) {
6377 			if (!has_cap_mac_admin(true)) {
6378 				struct audit_buffer *ab;
6379 				size_t audit_size;
6380 
6381 				/* We strip a nul only if it is at the end, otherwise the
6382 				 * context contains a nul and we should audit that */
6383 				if (str[size - 1] == '\0')
6384 					audit_size = size - 1;
6385 				else
6386 					audit_size = size;
6387 				ab = audit_log_start(audit_context(),
6388 						     GFP_ATOMIC,
6389 						     AUDIT_SELINUX_ERR);
6390 				if (!ab)
6391 					return error;
6392 				audit_log_format(ab, "op=fscreate invalid_context=");
6393 				audit_log_n_untrustedstring(ab, value, audit_size);
6394 				audit_log_end(ab);
6395 
6396 				return error;
6397 			}
6398 			error = security_context_to_sid_force(value, size,
6399 							&sid);
6400 		}
6401 		if (error)
6402 			return error;
6403 	}
6404 
6405 	new = prepare_creds();
6406 	if (!new)
6407 		return -ENOMEM;
6408 
6409 	/* Permission checking based on the specified context is
6410 	   performed during the actual operation (execve,
6411 	   open/mkdir/...), when we know the full context of the
6412 	   operation.  See selinux_bprm_creds_for_exec for the execve
6413 	   checks and may_create for the file creation checks. The
6414 	   operation will then fail if the context is not permitted. */
6415 	tsec = selinux_cred(new);
6416 	if (!strcmp(name, "exec")) {
6417 		tsec->exec_sid = sid;
6418 	} else if (!strcmp(name, "fscreate")) {
6419 		tsec->create_sid = sid;
6420 	} else if (!strcmp(name, "keycreate")) {
6421 		if (sid) {
6422 			error = avc_has_perm(mysid, sid,
6423 					     SECCLASS_KEY, KEY__CREATE, NULL);
6424 			if (error)
6425 				goto abort_change;
6426 		}
6427 		tsec->keycreate_sid = sid;
6428 	} else if (!strcmp(name, "sockcreate")) {
6429 		tsec->sockcreate_sid = sid;
6430 	} else if (!strcmp(name, "current")) {
6431 		error = -EINVAL;
6432 		if (sid == 0)
6433 			goto abort_change;
6434 
6435 		/* Only allow single threaded processes to change context */
6436 		if (!current_is_single_threaded()) {
6437 			error = security_bounded_transition(tsec->sid, sid);
6438 			if (error)
6439 				goto abort_change;
6440 		}
6441 
6442 		/* Check permissions for the transition. */
6443 		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6444 				     PROCESS__DYNTRANSITION, NULL);
6445 		if (error)
6446 			goto abort_change;
6447 
6448 		/* Check for ptracing, and update the task SID if ok.
6449 		   Otherwise, leave SID unchanged and fail. */
6450 		ptsid = ptrace_parent_sid();
6451 		if (ptsid != 0) {
6452 			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
6453 					     PROCESS__PTRACE, NULL);
6454 			if (error)
6455 				goto abort_change;
6456 		}
6457 
6458 		tsec->sid = sid;
6459 	} else {
6460 		error = -EINVAL;
6461 		goto abort_change;
6462 	}
6463 
6464 	commit_creds(new);
6465 	return size;
6466 
6467 abort_change:
6468 	abort_creds(new);
6469 	return error;
6470 }
6471 
6472 static int selinux_ismaclabel(const char *name)
6473 {
6474 	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6475 }
6476 
6477 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6478 {
6479 	return security_sid_to_context(secid,
6480 				       secdata, seclen);
6481 }
6482 
6483 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6484 {
6485 	return security_context_to_sid(secdata, seclen,
6486 				       secid, GFP_KERNEL);
6487 }
6488 
6489 static void selinux_release_secctx(char *secdata, u32 seclen)
6490 {
6491 	kfree(secdata);
6492 }
6493 
6494 static void selinux_inode_invalidate_secctx(struct inode *inode)
6495 {
6496 	struct inode_security_struct *isec = selinux_inode(inode);
6497 
6498 	spin_lock(&isec->lock);
6499 	isec->initialized = LABEL_INVALID;
6500 	spin_unlock(&isec->lock);
6501 }
6502 
6503 /*
6504  *	called with inode->i_mutex locked
6505  */
6506 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6507 {
6508 	int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6509 					   ctx, ctxlen, 0);
6510 	/* Do not return error when suppressing label (SBLABEL_MNT not set). */
6511 	return rc == -EOPNOTSUPP ? 0 : rc;
6512 }
6513 
6514 /*
6515  *	called with inode->i_mutex locked
6516  */
6517 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6518 {
6519 	return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6520 				     ctx, ctxlen, 0);
6521 }
6522 
6523 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6524 {
6525 	int len = 0;
6526 	len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6527 					XATTR_SELINUX_SUFFIX, ctx, true);
6528 	if (len < 0)
6529 		return len;
6530 	*ctxlen = len;
6531 	return 0;
6532 }
6533 #ifdef CONFIG_KEYS
6534 
6535 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6536 			     unsigned long flags)
6537 {
6538 	const struct task_security_struct *tsec;
6539 	struct key_security_struct *ksec;
6540 
6541 	ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6542 	if (!ksec)
6543 		return -ENOMEM;
6544 
6545 	tsec = selinux_cred(cred);
6546 	if (tsec->keycreate_sid)
6547 		ksec->sid = tsec->keycreate_sid;
6548 	else
6549 		ksec->sid = tsec->sid;
6550 
6551 	k->security = ksec;
6552 	return 0;
6553 }
6554 
6555 static void selinux_key_free(struct key *k)
6556 {
6557 	struct key_security_struct *ksec = k->security;
6558 
6559 	k->security = NULL;
6560 	kfree(ksec);
6561 }
6562 
6563 static int selinux_key_permission(key_ref_t key_ref,
6564 				  const struct cred *cred,
6565 				  enum key_need_perm need_perm)
6566 {
6567 	struct key *key;
6568 	struct key_security_struct *ksec;
6569 	u32 perm, sid;
6570 
6571 	switch (need_perm) {
6572 	case KEY_NEED_VIEW:
6573 		perm = KEY__VIEW;
6574 		break;
6575 	case KEY_NEED_READ:
6576 		perm = KEY__READ;
6577 		break;
6578 	case KEY_NEED_WRITE:
6579 		perm = KEY__WRITE;
6580 		break;
6581 	case KEY_NEED_SEARCH:
6582 		perm = KEY__SEARCH;
6583 		break;
6584 	case KEY_NEED_LINK:
6585 		perm = KEY__LINK;
6586 		break;
6587 	case KEY_NEED_SETATTR:
6588 		perm = KEY__SETATTR;
6589 		break;
6590 	case KEY_NEED_UNLINK:
6591 	case KEY_SYSADMIN_OVERRIDE:
6592 	case KEY_AUTHTOKEN_OVERRIDE:
6593 	case KEY_DEFER_PERM_CHECK:
6594 		return 0;
6595 	default:
6596 		WARN_ON(1);
6597 		return -EPERM;
6598 
6599 	}
6600 
6601 	sid = cred_sid(cred);
6602 	key = key_ref_to_ptr(key_ref);
6603 	ksec = key->security;
6604 
6605 	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6606 }
6607 
6608 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6609 {
6610 	struct key_security_struct *ksec = key->security;
6611 	char *context = NULL;
6612 	unsigned len;
6613 	int rc;
6614 
6615 	rc = security_sid_to_context(ksec->sid,
6616 				     &context, &len);
6617 	if (!rc)
6618 		rc = len;
6619 	*_buffer = context;
6620 	return rc;
6621 }
6622 
6623 #ifdef CONFIG_KEY_NOTIFICATIONS
6624 static int selinux_watch_key(struct key *key)
6625 {
6626 	struct key_security_struct *ksec = key->security;
6627 	u32 sid = current_sid();
6628 
6629 	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6630 }
6631 #endif
6632 #endif
6633 
6634 #ifdef CONFIG_SECURITY_INFINIBAND
6635 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6636 {
6637 	struct common_audit_data ad;
6638 	int err;
6639 	u32 sid = 0;
6640 	struct ib_security_struct *sec = ib_sec;
6641 	struct lsm_ibpkey_audit ibpkey;
6642 
6643 	err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6644 	if (err)
6645 		return err;
6646 
6647 	ad.type = LSM_AUDIT_DATA_IBPKEY;
6648 	ibpkey.subnet_prefix = subnet_prefix;
6649 	ibpkey.pkey = pkey_val;
6650 	ad.u.ibpkey = &ibpkey;
6651 	return avc_has_perm(sec->sid, sid,
6652 			    SECCLASS_INFINIBAND_PKEY,
6653 			    INFINIBAND_PKEY__ACCESS, &ad);
6654 }
6655 
6656 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6657 					    u8 port_num)
6658 {
6659 	struct common_audit_data ad;
6660 	int err;
6661 	u32 sid = 0;
6662 	struct ib_security_struct *sec = ib_sec;
6663 	struct lsm_ibendport_audit ibendport;
6664 
6665 	err = security_ib_endport_sid(dev_name, port_num,
6666 				      &sid);
6667 
6668 	if (err)
6669 		return err;
6670 
6671 	ad.type = LSM_AUDIT_DATA_IBENDPORT;
6672 	ibendport.dev_name = dev_name;
6673 	ibendport.port = port_num;
6674 	ad.u.ibendport = &ibendport;
6675 	return avc_has_perm(sec->sid, sid,
6676 			    SECCLASS_INFINIBAND_ENDPORT,
6677 			    INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6678 }
6679 
6680 static int selinux_ib_alloc_security(void **ib_sec)
6681 {
6682 	struct ib_security_struct *sec;
6683 
6684 	sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6685 	if (!sec)
6686 		return -ENOMEM;
6687 	sec->sid = current_sid();
6688 
6689 	*ib_sec = sec;
6690 	return 0;
6691 }
6692 
6693 static void selinux_ib_free_security(void *ib_sec)
6694 {
6695 	kfree(ib_sec);
6696 }
6697 #endif
6698 
6699 #ifdef CONFIG_BPF_SYSCALL
6700 static int selinux_bpf(int cmd, union bpf_attr *attr,
6701 				     unsigned int size)
6702 {
6703 	u32 sid = current_sid();
6704 	int ret;
6705 
6706 	switch (cmd) {
6707 	case BPF_MAP_CREATE:
6708 		ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6709 				   NULL);
6710 		break;
6711 	case BPF_PROG_LOAD:
6712 		ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6713 				   NULL);
6714 		break;
6715 	default:
6716 		ret = 0;
6717 		break;
6718 	}
6719 
6720 	return ret;
6721 }
6722 
6723 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6724 {
6725 	u32 av = 0;
6726 
6727 	if (fmode & FMODE_READ)
6728 		av |= BPF__MAP_READ;
6729 	if (fmode & FMODE_WRITE)
6730 		av |= BPF__MAP_WRITE;
6731 	return av;
6732 }
6733 
6734 /* This function will check the file pass through unix socket or binder to see
6735  * if it is a bpf related object. And apply corresponding checks on the bpf
6736  * object based on the type. The bpf maps and programs, not like other files and
6737  * socket, are using a shared anonymous inode inside the kernel as their inode.
6738  * So checking that inode cannot identify if the process have privilege to
6739  * access the bpf object and that's why we have to add this additional check in
6740  * selinux_file_receive and selinux_binder_transfer_files.
6741  */
6742 static int bpf_fd_pass(struct file *file, u32 sid)
6743 {
6744 	struct bpf_security_struct *bpfsec;
6745 	struct bpf_prog *prog;
6746 	struct bpf_map *map;
6747 	int ret;
6748 
6749 	if (file->f_op == &bpf_map_fops) {
6750 		map = file->private_data;
6751 		bpfsec = map->security;
6752 		ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6753 				   bpf_map_fmode_to_av(file->f_mode), NULL);
6754 		if (ret)
6755 			return ret;
6756 	} else if (file->f_op == &bpf_prog_fops) {
6757 		prog = file->private_data;
6758 		bpfsec = prog->aux->security;
6759 		ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6760 				   BPF__PROG_RUN, NULL);
6761 		if (ret)
6762 			return ret;
6763 	}
6764 	return 0;
6765 }
6766 
6767 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6768 {
6769 	u32 sid = current_sid();
6770 	struct bpf_security_struct *bpfsec;
6771 
6772 	bpfsec = map->security;
6773 	return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6774 			    bpf_map_fmode_to_av(fmode), NULL);
6775 }
6776 
6777 static int selinux_bpf_prog(struct bpf_prog *prog)
6778 {
6779 	u32 sid = current_sid();
6780 	struct bpf_security_struct *bpfsec;
6781 
6782 	bpfsec = prog->aux->security;
6783 	return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6784 			    BPF__PROG_RUN, NULL);
6785 }
6786 
6787 static int selinux_bpf_map_alloc(struct bpf_map *map)
6788 {
6789 	struct bpf_security_struct *bpfsec;
6790 
6791 	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6792 	if (!bpfsec)
6793 		return -ENOMEM;
6794 
6795 	bpfsec->sid = current_sid();
6796 	map->security = bpfsec;
6797 
6798 	return 0;
6799 }
6800 
6801 static void selinux_bpf_map_free(struct bpf_map *map)
6802 {
6803 	struct bpf_security_struct *bpfsec = map->security;
6804 
6805 	map->security = NULL;
6806 	kfree(bpfsec);
6807 }
6808 
6809 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6810 {
6811 	struct bpf_security_struct *bpfsec;
6812 
6813 	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6814 	if (!bpfsec)
6815 		return -ENOMEM;
6816 
6817 	bpfsec->sid = current_sid();
6818 	aux->security = bpfsec;
6819 
6820 	return 0;
6821 }
6822 
6823 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6824 {
6825 	struct bpf_security_struct *bpfsec = aux->security;
6826 
6827 	aux->security = NULL;
6828 	kfree(bpfsec);
6829 }
6830 #endif
6831 
6832 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
6833 	.lbs_cred = sizeof(struct task_security_struct),
6834 	.lbs_file = sizeof(struct file_security_struct),
6835 	.lbs_inode = sizeof(struct inode_security_struct),
6836 	.lbs_ipc = sizeof(struct ipc_security_struct),
6837 	.lbs_msg_msg = sizeof(struct msg_security_struct),
6838 	.lbs_superblock = sizeof(struct superblock_security_struct),
6839 };
6840 
6841 #ifdef CONFIG_PERF_EVENTS
6842 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
6843 {
6844 	u32 requested, sid = current_sid();
6845 
6846 	if (type == PERF_SECURITY_OPEN)
6847 		requested = PERF_EVENT__OPEN;
6848 	else if (type == PERF_SECURITY_CPU)
6849 		requested = PERF_EVENT__CPU;
6850 	else if (type == PERF_SECURITY_KERNEL)
6851 		requested = PERF_EVENT__KERNEL;
6852 	else if (type == PERF_SECURITY_TRACEPOINT)
6853 		requested = PERF_EVENT__TRACEPOINT;
6854 	else
6855 		return -EINVAL;
6856 
6857 	return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
6858 			    requested, NULL);
6859 }
6860 
6861 static int selinux_perf_event_alloc(struct perf_event *event)
6862 {
6863 	struct perf_event_security_struct *perfsec;
6864 
6865 	perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
6866 	if (!perfsec)
6867 		return -ENOMEM;
6868 
6869 	perfsec->sid = current_sid();
6870 	event->security = perfsec;
6871 
6872 	return 0;
6873 }
6874 
6875 static void selinux_perf_event_free(struct perf_event *event)
6876 {
6877 	struct perf_event_security_struct *perfsec = event->security;
6878 
6879 	event->security = NULL;
6880 	kfree(perfsec);
6881 }
6882 
6883 static int selinux_perf_event_read(struct perf_event *event)
6884 {
6885 	struct perf_event_security_struct *perfsec = event->security;
6886 	u32 sid = current_sid();
6887 
6888 	return avc_has_perm(sid, perfsec->sid,
6889 			    SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
6890 }
6891 
6892 static int selinux_perf_event_write(struct perf_event *event)
6893 {
6894 	struct perf_event_security_struct *perfsec = event->security;
6895 	u32 sid = current_sid();
6896 
6897 	return avc_has_perm(sid, perfsec->sid,
6898 			    SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
6899 }
6900 #endif
6901 
6902 #ifdef CONFIG_IO_URING
6903 /**
6904  * selinux_uring_override_creds - check the requested cred override
6905  * @new: the target creds
6906  *
6907  * Check to see if the current task is allowed to override it's credentials
6908  * to service an io_uring operation.
6909  */
6910 static int selinux_uring_override_creds(const struct cred *new)
6911 {
6912 	return avc_has_perm(current_sid(), cred_sid(new),
6913 			    SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
6914 }
6915 
6916 /**
6917  * selinux_uring_sqpoll - check if a io_uring polling thread can be created
6918  *
6919  * Check to see if the current task is allowed to create a new io_uring
6920  * kernel polling thread.
6921  */
6922 static int selinux_uring_sqpoll(void)
6923 {
6924 	int sid = current_sid();
6925 
6926 	return avc_has_perm(sid, sid,
6927 			    SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
6928 }
6929 
6930 /**
6931  * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
6932  * @ioucmd: the io_uring command structure
6933  *
6934  * Check to see if the current domain is allowed to execute an
6935  * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
6936  *
6937  */
6938 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
6939 {
6940 	struct file *file = ioucmd->file;
6941 	struct inode *inode = file_inode(file);
6942 	struct inode_security_struct *isec = selinux_inode(inode);
6943 	struct common_audit_data ad;
6944 
6945 	ad.type = LSM_AUDIT_DATA_FILE;
6946 	ad.u.file = file;
6947 
6948 	return avc_has_perm(current_sid(), isec->sid,
6949 			    SECCLASS_IO_URING, IO_URING__CMD, &ad);
6950 }
6951 #endif /* CONFIG_IO_URING */
6952 
6953 /*
6954  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
6955  * 1. any hooks that don't belong to (2.) or (3.) below,
6956  * 2. hooks that both access structures allocated by other hooks, and allocate
6957  *    structures that can be later accessed by other hooks (mostly "cloning"
6958  *    hooks),
6959  * 3. hooks that only allocate structures that can be later accessed by other
6960  *    hooks ("allocating" hooks).
6961  *
6962  * Please follow block comment delimiters in the list to keep this order.
6963  *
6964  * This ordering is needed for SELinux runtime disable to work at least somewhat
6965  * safely. Breaking the ordering rules above might lead to NULL pointer derefs
6966  * when disabling SELinux at runtime.
6967  */
6968 static struct security_hook_list selinux_hooks[] __ro_after_init = {
6969 	LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6970 	LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6971 	LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6972 	LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6973 
6974 	LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6975 	LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6976 	LSM_HOOK_INIT(capget, selinux_capget),
6977 	LSM_HOOK_INIT(capset, selinux_capset),
6978 	LSM_HOOK_INIT(capable, selinux_capable),
6979 	LSM_HOOK_INIT(quotactl, selinux_quotactl),
6980 	LSM_HOOK_INIT(quota_on, selinux_quota_on),
6981 	LSM_HOOK_INIT(syslog, selinux_syslog),
6982 	LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6983 
6984 	LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6985 
6986 	LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
6987 	LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6988 	LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6989 
6990 	LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
6991 	LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
6992 	LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6993 	LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6994 	LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6995 	LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6996 	LSM_HOOK_INIT(sb_mount, selinux_mount),
6997 	LSM_HOOK_INIT(sb_umount, selinux_umount),
6998 	LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6999 	LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7000 
7001 	LSM_HOOK_INIT(move_mount, selinux_move_mount),
7002 
7003 	LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7004 	LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7005 
7006 	LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7007 	LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7008 	LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7009 	LSM_HOOK_INIT(inode_create, selinux_inode_create),
7010 	LSM_HOOK_INIT(inode_link, selinux_inode_link),
7011 	LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7012 	LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7013 	LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7014 	LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7015 	LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7016 	LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7017 	LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7018 	LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7019 	LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7020 	LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7021 	LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7022 	LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7023 	LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7024 	LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7025 	LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7026 	LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7027 	LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7028 	LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7029 	LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7030 	LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7031 	LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7032 	LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7033 	LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7034 	LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7035 	LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7036 	LSM_HOOK_INIT(path_notify, selinux_path_notify),
7037 
7038 	LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7039 
7040 	LSM_HOOK_INIT(file_permission, selinux_file_permission),
7041 	LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7042 	LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7043 	LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7044 	LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7045 	LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7046 	LSM_HOOK_INIT(file_lock, selinux_file_lock),
7047 	LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7048 	LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7049 	LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7050 	LSM_HOOK_INIT(file_receive, selinux_file_receive),
7051 
7052 	LSM_HOOK_INIT(file_open, selinux_file_open),
7053 
7054 	LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7055 	LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7056 	LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7057 	LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7058 	LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7059 	LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7060 	LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7061 	LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7062 	LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7063 	LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7064 	LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7065 	LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7066 	LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj),
7067 	LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj),
7068 	LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7069 	LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7070 	LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7071 	LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7072 	LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7073 	LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7074 	LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7075 	LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7076 	LSM_HOOK_INIT(task_kill, selinux_task_kill),
7077 	LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7078 	LSM_HOOK_INIT(userns_create, selinux_userns_create),
7079 
7080 	LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7081 	LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7082 
7083 	LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7084 	LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7085 	LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7086 	LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7087 
7088 	LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7089 	LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7090 	LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7091 
7092 	LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7093 	LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7094 	LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7095 
7096 	LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7097 
7098 	LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7099 	LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7100 
7101 	LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7102 	LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7103 	LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7104 	LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7105 	LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7106 	LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7107 
7108 	LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7109 	LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7110 
7111 	LSM_HOOK_INIT(socket_create, selinux_socket_create),
7112 	LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7113 	LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7114 	LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7115 	LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7116 	LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7117 	LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7118 	LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7119 	LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7120 	LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7121 	LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7122 	LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7123 	LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7124 	LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7125 	LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7126 	LSM_HOOK_INIT(socket_getpeersec_stream,
7127 			selinux_socket_getpeersec_stream),
7128 	LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7129 	LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7130 	LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7131 	LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7132 	LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7133 	LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7134 	LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7135 	LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7136 	LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7137 	LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow),
7138 	LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7139 	LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7140 	LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7141 	LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7142 	LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7143 	LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7144 	LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7145 	LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7146 	LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7147 	LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7148 	LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7149 	LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7150 #ifdef CONFIG_SECURITY_INFINIBAND
7151 	LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7152 	LSM_HOOK_INIT(ib_endport_manage_subnet,
7153 		      selinux_ib_endport_manage_subnet),
7154 	LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7155 #endif
7156 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7157 	LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7158 	LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7159 	LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7160 	LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7161 	LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7162 	LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7163 			selinux_xfrm_state_pol_flow_match),
7164 	LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7165 #endif
7166 
7167 #ifdef CONFIG_KEYS
7168 	LSM_HOOK_INIT(key_free, selinux_key_free),
7169 	LSM_HOOK_INIT(key_permission, selinux_key_permission),
7170 	LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7171 #ifdef CONFIG_KEY_NOTIFICATIONS
7172 	LSM_HOOK_INIT(watch_key, selinux_watch_key),
7173 #endif
7174 #endif
7175 
7176 #ifdef CONFIG_AUDIT
7177 	LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7178 	LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7179 	LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7180 #endif
7181 
7182 #ifdef CONFIG_BPF_SYSCALL
7183 	LSM_HOOK_INIT(bpf, selinux_bpf),
7184 	LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7185 	LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7186 	LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7187 	LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7188 #endif
7189 
7190 #ifdef CONFIG_PERF_EVENTS
7191 	LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7192 	LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7193 	LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7194 	LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7195 #endif
7196 
7197 #ifdef CONFIG_IO_URING
7198 	LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7199 	LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7200 	LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7201 #endif
7202 
7203 	/*
7204 	 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7205 	 */
7206 	LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount),
7207 	LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7208 	LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7209 	LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7210 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7211 	LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7212 #endif
7213 
7214 	/*
7215 	 * PUT "ALLOCATING" HOOKS HERE
7216 	 */
7217 	LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7218 	LSM_HOOK_INIT(msg_queue_alloc_security,
7219 		      selinux_msg_queue_alloc_security),
7220 	LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7221 	LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7222 	LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7223 	LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7224 	LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7225 	LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7226 	LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7227 	LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7228 #ifdef CONFIG_SECURITY_INFINIBAND
7229 	LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7230 #endif
7231 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7232 	LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7233 	LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7234 	LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7235 		      selinux_xfrm_state_alloc_acquire),
7236 #endif
7237 #ifdef CONFIG_KEYS
7238 	LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7239 #endif
7240 #ifdef CONFIG_AUDIT
7241 	LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7242 #endif
7243 #ifdef CONFIG_BPF_SYSCALL
7244 	LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7245 	LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7246 #endif
7247 #ifdef CONFIG_PERF_EVENTS
7248 	LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7249 #endif
7250 };
7251 
7252 static __init int selinux_init(void)
7253 {
7254 	pr_info("SELinux:  Initializing.\n");
7255 
7256 	memset(&selinux_state, 0, sizeof(selinux_state));
7257 	enforcing_set(selinux_enforcing_boot);
7258 	selinux_avc_init();
7259 	mutex_init(&selinux_state.status_lock);
7260 	mutex_init(&selinux_state.policy_mutex);
7261 
7262 	/* Set the security state for the initial task. */
7263 	cred_init_security();
7264 
7265 	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7266 
7267 	avc_init();
7268 
7269 	avtab_cache_init();
7270 
7271 	ebitmap_cache_init();
7272 
7273 	hashtab_cache_init();
7274 
7275 	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7276 
7277 	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7278 		panic("SELinux: Unable to register AVC netcache callback\n");
7279 
7280 	if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7281 		panic("SELinux: Unable to register AVC LSM notifier callback\n");
7282 
7283 	if (selinux_enforcing_boot)
7284 		pr_debug("SELinux:  Starting in enforcing mode\n");
7285 	else
7286 		pr_debug("SELinux:  Starting in permissive mode\n");
7287 
7288 	fs_validate_description("selinux", selinux_fs_parameters);
7289 
7290 	return 0;
7291 }
7292 
7293 static void delayed_superblock_init(struct super_block *sb, void *unused)
7294 {
7295 	selinux_set_mnt_opts(sb, NULL, 0, NULL);
7296 }
7297 
7298 void selinux_complete_init(void)
7299 {
7300 	pr_debug("SELinux:  Completing initialization.\n");
7301 
7302 	/* Set up any superblocks initialized prior to the policy load. */
7303 	pr_debug("SELinux:  Setting up existing superblocks.\n");
7304 	iterate_supers(delayed_superblock_init, NULL);
7305 }
7306 
7307 /* SELinux requires early initialization in order to label
7308    all processes and objects when they are created. */
7309 DEFINE_LSM(selinux) = {
7310 	.name = "selinux",
7311 	.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7312 	.enabled = &selinux_enabled_boot,
7313 	.blobs = &selinux_blob_sizes,
7314 	.init = selinux_init,
7315 };
7316 
7317 #if defined(CONFIG_NETFILTER)
7318 static const struct nf_hook_ops selinux_nf_ops[] = {
7319 	{
7320 		.hook =		selinux_ip_postroute,
7321 		.pf =		NFPROTO_IPV4,
7322 		.hooknum =	NF_INET_POST_ROUTING,
7323 		.priority =	NF_IP_PRI_SELINUX_LAST,
7324 	},
7325 	{
7326 		.hook =		selinux_ip_forward,
7327 		.pf =		NFPROTO_IPV4,
7328 		.hooknum =	NF_INET_FORWARD,
7329 		.priority =	NF_IP_PRI_SELINUX_FIRST,
7330 	},
7331 	{
7332 		.hook =		selinux_ip_output,
7333 		.pf =		NFPROTO_IPV4,
7334 		.hooknum =	NF_INET_LOCAL_OUT,
7335 		.priority =	NF_IP_PRI_SELINUX_FIRST,
7336 	},
7337 #if IS_ENABLED(CONFIG_IPV6)
7338 	{
7339 		.hook =		selinux_ip_postroute,
7340 		.pf =		NFPROTO_IPV6,
7341 		.hooknum =	NF_INET_POST_ROUTING,
7342 		.priority =	NF_IP6_PRI_SELINUX_LAST,
7343 	},
7344 	{
7345 		.hook =		selinux_ip_forward,
7346 		.pf =		NFPROTO_IPV6,
7347 		.hooknum =	NF_INET_FORWARD,
7348 		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7349 	},
7350 	{
7351 		.hook =		selinux_ip_output,
7352 		.pf =		NFPROTO_IPV6,
7353 		.hooknum =	NF_INET_LOCAL_OUT,
7354 		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7355 	},
7356 #endif	/* IPV6 */
7357 };
7358 
7359 static int __net_init selinux_nf_register(struct net *net)
7360 {
7361 	return nf_register_net_hooks(net, selinux_nf_ops,
7362 				     ARRAY_SIZE(selinux_nf_ops));
7363 }
7364 
7365 static void __net_exit selinux_nf_unregister(struct net *net)
7366 {
7367 	nf_unregister_net_hooks(net, selinux_nf_ops,
7368 				ARRAY_SIZE(selinux_nf_ops));
7369 }
7370 
7371 static struct pernet_operations selinux_net_ops = {
7372 	.init = selinux_nf_register,
7373 	.exit = selinux_nf_unregister,
7374 };
7375 
7376 static int __init selinux_nf_ip_init(void)
7377 {
7378 	int err;
7379 
7380 	if (!selinux_enabled_boot)
7381 		return 0;
7382 
7383 	pr_debug("SELinux:  Registering netfilter hooks\n");
7384 
7385 	err = register_pernet_subsys(&selinux_net_ops);
7386 	if (err)
7387 		panic("SELinux: register_pernet_subsys: error %d\n", err);
7388 
7389 	return 0;
7390 }
7391 __initcall(selinux_nf_ip_init);
7392 #endif /* CONFIG_NETFILTER */
7393