xref: /openbmc/linux/security/selinux/hooks.c (revision 55fd7e02)
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/tracehook.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 
95 #include "avc.h"
96 #include "objsec.h"
97 #include "netif.h"
98 #include "netnode.h"
99 #include "netport.h"
100 #include "ibpkey.h"
101 #include "xfrm.h"
102 #include "netlabel.h"
103 #include "audit.h"
104 #include "avc_ss.h"
105 
106 struct selinux_state selinux_state;
107 
108 /* SECMARK reference count */
109 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
110 
111 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
112 static int selinux_enforcing_boot __initdata;
113 
114 static int __init enforcing_setup(char *str)
115 {
116 	unsigned long enforcing;
117 	if (!kstrtoul(str, 0, &enforcing))
118 		selinux_enforcing_boot = enforcing ? 1 : 0;
119 	return 1;
120 }
121 __setup("enforcing=", enforcing_setup);
122 #else
123 #define selinux_enforcing_boot 1
124 #endif
125 
126 int selinux_enabled_boot __initdata = 1;
127 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
128 static int __init selinux_enabled_setup(char *str)
129 {
130 	unsigned long enabled;
131 	if (!kstrtoul(str, 0, &enabled))
132 		selinux_enabled_boot = enabled ? 1 : 0;
133 	return 1;
134 }
135 __setup("selinux=", selinux_enabled_setup);
136 #endif
137 
138 static unsigned int selinux_checkreqprot_boot =
139 	CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
140 
141 static int __init checkreqprot_setup(char *str)
142 {
143 	unsigned long checkreqprot;
144 
145 	if (!kstrtoul(str, 0, &checkreqprot)) {
146 		selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
147 		if (checkreqprot)
148 			pr_warn("SELinux: checkreqprot set to 1 via kernel parameter.  This is deprecated and will be rejected in a future kernel release.\n");
149 	}
150 	return 1;
151 }
152 __setup("checkreqprot=", checkreqprot_setup);
153 
154 /**
155  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
156  *
157  * Description:
158  * This function checks the SECMARK reference counter to see if any SECMARK
159  * targets are currently configured, if the reference counter is greater than
160  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
161  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
162  * policy capability is enabled, SECMARK is always considered enabled.
163  *
164  */
165 static int selinux_secmark_enabled(void)
166 {
167 	return (selinux_policycap_alwaysnetwork() ||
168 		atomic_read(&selinux_secmark_refcount));
169 }
170 
171 /**
172  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
173  *
174  * Description:
175  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
176  * (1) if any are enabled or false (0) if neither are enabled.  If the
177  * always_check_network policy capability is enabled, peer labeling
178  * is always considered enabled.
179  *
180  */
181 static int selinux_peerlbl_enabled(void)
182 {
183 	return (selinux_policycap_alwaysnetwork() ||
184 		netlbl_enabled() || selinux_xfrm_enabled());
185 }
186 
187 static int selinux_netcache_avc_callback(u32 event)
188 {
189 	if (event == AVC_CALLBACK_RESET) {
190 		sel_netif_flush();
191 		sel_netnode_flush();
192 		sel_netport_flush();
193 		synchronize_net();
194 	}
195 	return 0;
196 }
197 
198 static int selinux_lsm_notifier_avc_callback(u32 event)
199 {
200 	if (event == AVC_CALLBACK_RESET) {
201 		sel_ib_pkey_flush();
202 		call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
203 	}
204 
205 	return 0;
206 }
207 
208 /*
209  * initialise the security for the init task
210  */
211 static void cred_init_security(void)
212 {
213 	struct cred *cred = (struct cred *) current->real_cred;
214 	struct task_security_struct *tsec;
215 
216 	tsec = selinux_cred(cred);
217 	tsec->osid = tsec->sid = SECINITSID_KERNEL;
218 }
219 
220 /*
221  * get the security ID of a set of credentials
222  */
223 static inline u32 cred_sid(const struct cred *cred)
224 {
225 	const struct task_security_struct *tsec;
226 
227 	tsec = selinux_cred(cred);
228 	return tsec->sid;
229 }
230 
231 /*
232  * get the objective security ID of a task
233  */
234 static inline u32 task_sid(const struct task_struct *task)
235 {
236 	u32 sid;
237 
238 	rcu_read_lock();
239 	sid = cred_sid(__task_cred(task));
240 	rcu_read_unlock();
241 	return sid;
242 }
243 
244 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
245 
246 /*
247  * Try reloading inode security labels that have been marked as invalid.  The
248  * @may_sleep parameter indicates when sleeping and thus reloading labels is
249  * allowed; when set to false, returns -ECHILD when the label is
250  * invalid.  The @dentry parameter should be set to a dentry of the inode.
251  */
252 static int __inode_security_revalidate(struct inode *inode,
253 				       struct dentry *dentry,
254 				       bool may_sleep)
255 {
256 	struct inode_security_struct *isec = selinux_inode(inode);
257 
258 	might_sleep_if(may_sleep);
259 
260 	if (selinux_initialized(&selinux_state) &&
261 	    isec->initialized != LABEL_INITIALIZED) {
262 		if (!may_sleep)
263 			return -ECHILD;
264 
265 		/*
266 		 * Try reloading the inode security label.  This will fail if
267 		 * @opt_dentry is NULL and no dentry for this inode can be
268 		 * found; in that case, continue using the old label.
269 		 */
270 		inode_doinit_with_dentry(inode, dentry);
271 	}
272 	return 0;
273 }
274 
275 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
276 {
277 	return selinux_inode(inode);
278 }
279 
280 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
281 {
282 	int error;
283 
284 	error = __inode_security_revalidate(inode, NULL, !rcu);
285 	if (error)
286 		return ERR_PTR(error);
287 	return selinux_inode(inode);
288 }
289 
290 /*
291  * Get the security label of an inode.
292  */
293 static struct inode_security_struct *inode_security(struct inode *inode)
294 {
295 	__inode_security_revalidate(inode, NULL, true);
296 	return selinux_inode(inode);
297 }
298 
299 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
300 {
301 	struct inode *inode = d_backing_inode(dentry);
302 
303 	return selinux_inode(inode);
304 }
305 
306 /*
307  * Get the security label of a dentry's backing inode.
308  */
309 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
310 {
311 	struct inode *inode = d_backing_inode(dentry);
312 
313 	__inode_security_revalidate(inode, dentry, true);
314 	return selinux_inode(inode);
315 }
316 
317 static void inode_free_security(struct inode *inode)
318 {
319 	struct inode_security_struct *isec = selinux_inode(inode);
320 	struct superblock_security_struct *sbsec;
321 
322 	if (!isec)
323 		return;
324 	sbsec = inode->i_sb->s_security;
325 	/*
326 	 * As not all inode security structures are in a list, we check for
327 	 * empty list outside of the lock to make sure that we won't waste
328 	 * time taking a lock doing nothing.
329 	 *
330 	 * The list_del_init() function can be safely called more than once.
331 	 * It should not be possible for this function to be called with
332 	 * concurrent list_add(), but for better safety against future changes
333 	 * in the code, we use list_empty_careful() here.
334 	 */
335 	if (!list_empty_careful(&isec->list)) {
336 		spin_lock(&sbsec->isec_lock);
337 		list_del_init(&isec->list);
338 		spin_unlock(&sbsec->isec_lock);
339 	}
340 }
341 
342 static void superblock_free_security(struct super_block *sb)
343 {
344 	struct superblock_security_struct *sbsec = sb->s_security;
345 	sb->s_security = NULL;
346 	kfree(sbsec);
347 }
348 
349 struct selinux_mnt_opts {
350 	const char *fscontext, *context, *rootcontext, *defcontext;
351 };
352 
353 static void selinux_free_mnt_opts(void *mnt_opts)
354 {
355 	struct selinux_mnt_opts *opts = mnt_opts;
356 	kfree(opts->fscontext);
357 	kfree(opts->context);
358 	kfree(opts->rootcontext);
359 	kfree(opts->defcontext);
360 	kfree(opts);
361 }
362 
363 enum {
364 	Opt_error = -1,
365 	Opt_context = 0,
366 	Opt_defcontext = 1,
367 	Opt_fscontext = 2,
368 	Opt_rootcontext = 3,
369 	Opt_seclabel = 4,
370 };
371 
372 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
373 static struct {
374 	const char *name;
375 	int len;
376 	int opt;
377 	bool has_arg;
378 } tokens[] = {
379 	A(context, true),
380 	A(fscontext, true),
381 	A(defcontext, true),
382 	A(rootcontext, true),
383 	A(seclabel, false),
384 };
385 #undef A
386 
387 static int match_opt_prefix(char *s, int l, char **arg)
388 {
389 	int i;
390 
391 	for (i = 0; i < ARRAY_SIZE(tokens); i++) {
392 		size_t len = tokens[i].len;
393 		if (len > l || memcmp(s, tokens[i].name, len))
394 			continue;
395 		if (tokens[i].has_arg) {
396 			if (len == l || s[len] != '=')
397 				continue;
398 			*arg = s + len + 1;
399 		} else if (len != l)
400 			continue;
401 		return tokens[i].opt;
402 	}
403 	return Opt_error;
404 }
405 
406 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
407 
408 static int may_context_mount_sb_relabel(u32 sid,
409 			struct superblock_security_struct *sbsec,
410 			const struct cred *cred)
411 {
412 	const struct task_security_struct *tsec = selinux_cred(cred);
413 	int rc;
414 
415 	rc = avc_has_perm(&selinux_state,
416 			  tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
417 			  FILESYSTEM__RELABELFROM, NULL);
418 	if (rc)
419 		return rc;
420 
421 	rc = avc_has_perm(&selinux_state,
422 			  tsec->sid, sid, SECCLASS_FILESYSTEM,
423 			  FILESYSTEM__RELABELTO, NULL);
424 	return rc;
425 }
426 
427 static int may_context_mount_inode_relabel(u32 sid,
428 			struct superblock_security_struct *sbsec,
429 			const struct cred *cred)
430 {
431 	const struct task_security_struct *tsec = selinux_cred(cred);
432 	int rc;
433 	rc = avc_has_perm(&selinux_state,
434 			  tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
435 			  FILESYSTEM__RELABELFROM, NULL);
436 	if (rc)
437 		return rc;
438 
439 	rc = avc_has_perm(&selinux_state,
440 			  sid, sbsec->sid, SECCLASS_FILESYSTEM,
441 			  FILESYSTEM__ASSOCIATE, NULL);
442 	return rc;
443 }
444 
445 static int selinux_is_genfs_special_handling(struct super_block *sb)
446 {
447 	/* Special handling. Genfs but also in-core setxattr handler */
448 	return	!strcmp(sb->s_type->name, "sysfs") ||
449 		!strcmp(sb->s_type->name, "pstore") ||
450 		!strcmp(sb->s_type->name, "debugfs") ||
451 		!strcmp(sb->s_type->name, "tracefs") ||
452 		!strcmp(sb->s_type->name, "rootfs") ||
453 		(selinux_policycap_cgroupseclabel() &&
454 		 (!strcmp(sb->s_type->name, "cgroup") ||
455 		  !strcmp(sb->s_type->name, "cgroup2")));
456 }
457 
458 static int selinux_is_sblabel_mnt(struct super_block *sb)
459 {
460 	struct superblock_security_struct *sbsec = sb->s_security;
461 
462 	/*
463 	 * IMPORTANT: Double-check logic in this function when adding a new
464 	 * SECURITY_FS_USE_* definition!
465 	 */
466 	BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
467 
468 	switch (sbsec->behavior) {
469 	case SECURITY_FS_USE_XATTR:
470 	case SECURITY_FS_USE_TRANS:
471 	case SECURITY_FS_USE_TASK:
472 	case SECURITY_FS_USE_NATIVE:
473 		return 1;
474 
475 	case SECURITY_FS_USE_GENFS:
476 		return selinux_is_genfs_special_handling(sb);
477 
478 	/* Never allow relabeling on context mounts */
479 	case SECURITY_FS_USE_MNTPOINT:
480 	case SECURITY_FS_USE_NONE:
481 	default:
482 		return 0;
483 	}
484 }
485 
486 static int sb_finish_set_opts(struct super_block *sb)
487 {
488 	struct superblock_security_struct *sbsec = sb->s_security;
489 	struct dentry *root = sb->s_root;
490 	struct inode *root_inode = d_backing_inode(root);
491 	int rc = 0;
492 
493 	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
494 		/* Make sure that the xattr handler exists and that no
495 		   error other than -ENODATA is returned by getxattr on
496 		   the root directory.  -ENODATA is ok, as this may be
497 		   the first boot of the SELinux kernel before we have
498 		   assigned xattr values to the filesystem. */
499 		if (!(root_inode->i_opflags & IOP_XATTR)) {
500 			pr_warn("SELinux: (dev %s, type %s) has no "
501 			       "xattr support\n", sb->s_id, sb->s_type->name);
502 			rc = -EOPNOTSUPP;
503 			goto out;
504 		}
505 
506 		rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
507 		if (rc < 0 && rc != -ENODATA) {
508 			if (rc == -EOPNOTSUPP)
509 				pr_warn("SELinux: (dev %s, type "
510 				       "%s) has no security xattr handler\n",
511 				       sb->s_id, sb->s_type->name);
512 			else
513 				pr_warn("SELinux: (dev %s, type "
514 				       "%s) getxattr errno %d\n", sb->s_id,
515 				       sb->s_type->name, -rc);
516 			goto out;
517 		}
518 	}
519 
520 	sbsec->flags |= SE_SBINITIALIZED;
521 
522 	/*
523 	 * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
524 	 * leave the flag untouched because sb_clone_mnt_opts might be handing
525 	 * us a superblock that needs the flag to be cleared.
526 	 */
527 	if (selinux_is_sblabel_mnt(sb))
528 		sbsec->flags |= SBLABEL_MNT;
529 	else
530 		sbsec->flags &= ~SBLABEL_MNT;
531 
532 	/* Initialize the root inode. */
533 	rc = inode_doinit_with_dentry(root_inode, root);
534 
535 	/* Initialize any other inodes associated with the superblock, e.g.
536 	   inodes created prior to initial policy load or inodes created
537 	   during get_sb by a pseudo filesystem that directly
538 	   populates itself. */
539 	spin_lock(&sbsec->isec_lock);
540 	while (!list_empty(&sbsec->isec_head)) {
541 		struct inode_security_struct *isec =
542 				list_first_entry(&sbsec->isec_head,
543 					   struct inode_security_struct, list);
544 		struct inode *inode = isec->inode;
545 		list_del_init(&isec->list);
546 		spin_unlock(&sbsec->isec_lock);
547 		inode = igrab(inode);
548 		if (inode) {
549 			if (!IS_PRIVATE(inode))
550 				inode_doinit_with_dentry(inode, NULL);
551 			iput(inode);
552 		}
553 		spin_lock(&sbsec->isec_lock);
554 	}
555 	spin_unlock(&sbsec->isec_lock);
556 out:
557 	return rc;
558 }
559 
560 static int bad_option(struct superblock_security_struct *sbsec, char flag,
561 		      u32 old_sid, u32 new_sid)
562 {
563 	char mnt_flags = sbsec->flags & SE_MNTMASK;
564 
565 	/* check if the old mount command had the same options */
566 	if (sbsec->flags & SE_SBINITIALIZED)
567 		if (!(sbsec->flags & flag) ||
568 		    (old_sid != new_sid))
569 			return 1;
570 
571 	/* check if we were passed the same options twice,
572 	 * aka someone passed context=a,context=b
573 	 */
574 	if (!(sbsec->flags & SE_SBINITIALIZED))
575 		if (mnt_flags & flag)
576 			return 1;
577 	return 0;
578 }
579 
580 static int parse_sid(struct super_block *sb, const char *s, u32 *sid)
581 {
582 	int rc = security_context_str_to_sid(&selinux_state, s,
583 					     sid, GFP_KERNEL);
584 	if (rc)
585 		pr_warn("SELinux: security_context_str_to_sid"
586 		       "(%s) failed for (dev %s, type %s) errno=%d\n",
587 		       s, sb->s_id, sb->s_type->name, rc);
588 	return rc;
589 }
590 
591 /*
592  * Allow filesystems with binary mount data to explicitly set mount point
593  * labeling information.
594  */
595 static int selinux_set_mnt_opts(struct super_block *sb,
596 				void *mnt_opts,
597 				unsigned long kern_flags,
598 				unsigned long *set_kern_flags)
599 {
600 	const struct cred *cred = current_cred();
601 	struct superblock_security_struct *sbsec = sb->s_security;
602 	struct dentry *root = sbsec->sb->s_root;
603 	struct selinux_mnt_opts *opts = mnt_opts;
604 	struct inode_security_struct *root_isec;
605 	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
606 	u32 defcontext_sid = 0;
607 	int rc = 0;
608 
609 	mutex_lock(&sbsec->lock);
610 
611 	if (!selinux_initialized(&selinux_state)) {
612 		if (!opts) {
613 			/* Defer initialization until selinux_complete_init,
614 			   after the initial policy is loaded and the security
615 			   server is ready to handle calls. */
616 			goto out;
617 		}
618 		rc = -EINVAL;
619 		pr_warn("SELinux: Unable to set superblock options "
620 			"before the security server is initialized\n");
621 		goto out;
622 	}
623 	if (kern_flags && !set_kern_flags) {
624 		/* Specifying internal flags without providing a place to
625 		 * place the results is not allowed */
626 		rc = -EINVAL;
627 		goto out;
628 	}
629 
630 	/*
631 	 * Binary mount data FS will come through this function twice.  Once
632 	 * from an explicit call and once from the generic calls from the vfs.
633 	 * Since the generic VFS calls will not contain any security mount data
634 	 * we need to skip the double mount verification.
635 	 *
636 	 * This does open a hole in which we will not notice if the first
637 	 * mount using this sb set explict options and a second mount using
638 	 * this sb does not set any security options.  (The first options
639 	 * will be used for both mounts)
640 	 */
641 	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
642 	    && !opts)
643 		goto out;
644 
645 	root_isec = backing_inode_security_novalidate(root);
646 
647 	/*
648 	 * parse the mount options, check if they are valid sids.
649 	 * also check if someone is trying to mount the same sb more
650 	 * than once with different security options.
651 	 */
652 	if (opts) {
653 		if (opts->fscontext) {
654 			rc = parse_sid(sb, opts->fscontext, &fscontext_sid);
655 			if (rc)
656 				goto out;
657 			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
658 					fscontext_sid))
659 				goto out_double_mount;
660 			sbsec->flags |= FSCONTEXT_MNT;
661 		}
662 		if (opts->context) {
663 			rc = parse_sid(sb, opts->context, &context_sid);
664 			if (rc)
665 				goto out;
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) {
672 			rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid);
673 			if (rc)
674 				goto out;
675 			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
676 					rootcontext_sid))
677 				goto out_double_mount;
678 			sbsec->flags |= ROOTCONTEXT_MNT;
679 		}
680 		if (opts->defcontext) {
681 			rc = parse_sid(sb, opts->defcontext, &defcontext_sid);
682 			if (rc)
683 				goto out;
684 			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
685 					defcontext_sid))
686 				goto out_double_mount;
687 			sbsec->flags |= DEFCONTEXT_MNT;
688 		}
689 	}
690 
691 	if (sbsec->flags & SE_SBINITIALIZED) {
692 		/* previously mounted with options, but not on this attempt? */
693 		if ((sbsec->flags & SE_MNTMASK) && !opts)
694 			goto out_double_mount;
695 		rc = 0;
696 		goto out;
697 	}
698 
699 	if (strcmp(sb->s_type->name, "proc") == 0)
700 		sbsec->flags |= SE_SBPROC | SE_SBGENFS;
701 
702 	if (!strcmp(sb->s_type->name, "debugfs") ||
703 	    !strcmp(sb->s_type->name, "tracefs") ||
704 	    !strcmp(sb->s_type->name, "binder") ||
705 	    !strcmp(sb->s_type->name, "bpf") ||
706 	    !strcmp(sb->s_type->name, "pstore"))
707 		sbsec->flags |= SE_SBGENFS;
708 
709 	if (!strcmp(sb->s_type->name, "sysfs") ||
710 	    !strcmp(sb->s_type->name, "cgroup") ||
711 	    !strcmp(sb->s_type->name, "cgroup2"))
712 		sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
713 
714 	if (!sbsec->behavior) {
715 		/*
716 		 * Determine the labeling behavior to use for this
717 		 * filesystem type.
718 		 */
719 		rc = security_fs_use(&selinux_state, sb);
720 		if (rc) {
721 			pr_warn("%s: security_fs_use(%s) returned %d\n",
722 					__func__, sb->s_type->name, rc);
723 			goto out;
724 		}
725 	}
726 
727 	/*
728 	 * If this is a user namespace mount and the filesystem type is not
729 	 * explicitly whitelisted, then no contexts are allowed on the command
730 	 * line and security labels must be ignored.
731 	 */
732 	if (sb->s_user_ns != &init_user_ns &&
733 	    strcmp(sb->s_type->name, "tmpfs") &&
734 	    strcmp(sb->s_type->name, "ramfs") &&
735 	    strcmp(sb->s_type->name, "devpts")) {
736 		if (context_sid || fscontext_sid || rootcontext_sid ||
737 		    defcontext_sid) {
738 			rc = -EACCES;
739 			goto out;
740 		}
741 		if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
742 			sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
743 			rc = security_transition_sid(&selinux_state,
744 						     current_sid(),
745 						     current_sid(),
746 						     SECCLASS_FILE, NULL,
747 						     &sbsec->mntpoint_sid);
748 			if (rc)
749 				goto out;
750 		}
751 		goto out_set_opts;
752 	}
753 
754 	/* sets the context of the superblock for the fs being mounted. */
755 	if (fscontext_sid) {
756 		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
757 		if (rc)
758 			goto out;
759 
760 		sbsec->sid = fscontext_sid;
761 	}
762 
763 	/*
764 	 * Switch to using mount point labeling behavior.
765 	 * sets the label used on all file below the mountpoint, and will set
766 	 * the superblock context if not already set.
767 	 */
768 	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
769 		sbsec->behavior = SECURITY_FS_USE_NATIVE;
770 		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
771 	}
772 
773 	if (context_sid) {
774 		if (!fscontext_sid) {
775 			rc = may_context_mount_sb_relabel(context_sid, sbsec,
776 							  cred);
777 			if (rc)
778 				goto out;
779 			sbsec->sid = context_sid;
780 		} else {
781 			rc = may_context_mount_inode_relabel(context_sid, sbsec,
782 							     cred);
783 			if (rc)
784 				goto out;
785 		}
786 		if (!rootcontext_sid)
787 			rootcontext_sid = context_sid;
788 
789 		sbsec->mntpoint_sid = context_sid;
790 		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
791 	}
792 
793 	if (rootcontext_sid) {
794 		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
795 						     cred);
796 		if (rc)
797 			goto out;
798 
799 		root_isec->sid = rootcontext_sid;
800 		root_isec->initialized = LABEL_INITIALIZED;
801 	}
802 
803 	if (defcontext_sid) {
804 		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
805 			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
806 			rc = -EINVAL;
807 			pr_warn("SELinux: defcontext option is "
808 			       "invalid for this filesystem type\n");
809 			goto out;
810 		}
811 
812 		if (defcontext_sid != sbsec->def_sid) {
813 			rc = may_context_mount_inode_relabel(defcontext_sid,
814 							     sbsec, cred);
815 			if (rc)
816 				goto out;
817 		}
818 
819 		sbsec->def_sid = defcontext_sid;
820 	}
821 
822 out_set_opts:
823 	rc = sb_finish_set_opts(sb);
824 out:
825 	mutex_unlock(&sbsec->lock);
826 	return rc;
827 out_double_mount:
828 	rc = -EINVAL;
829 	pr_warn("SELinux: mount invalid.  Same superblock, different "
830 	       "security settings for (dev %s, type %s)\n", sb->s_id,
831 	       sb->s_type->name);
832 	goto out;
833 }
834 
835 static int selinux_cmp_sb_context(const struct super_block *oldsb,
836 				    const struct super_block *newsb)
837 {
838 	struct superblock_security_struct *old = oldsb->s_security;
839 	struct superblock_security_struct *new = newsb->s_security;
840 	char oldflags = old->flags & SE_MNTMASK;
841 	char newflags = new->flags & SE_MNTMASK;
842 
843 	if (oldflags != newflags)
844 		goto mismatch;
845 	if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
846 		goto mismatch;
847 	if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
848 		goto mismatch;
849 	if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
850 		goto mismatch;
851 	if (oldflags & ROOTCONTEXT_MNT) {
852 		struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
853 		struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
854 		if (oldroot->sid != newroot->sid)
855 			goto mismatch;
856 	}
857 	return 0;
858 mismatch:
859 	pr_warn("SELinux: mount invalid.  Same superblock, "
860 			    "different security settings for (dev %s, "
861 			    "type %s)\n", newsb->s_id, newsb->s_type->name);
862 	return -EBUSY;
863 }
864 
865 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
866 					struct super_block *newsb,
867 					unsigned long kern_flags,
868 					unsigned long *set_kern_flags)
869 {
870 	int rc = 0;
871 	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
872 	struct superblock_security_struct *newsbsec = newsb->s_security;
873 
874 	int set_fscontext =	(oldsbsec->flags & FSCONTEXT_MNT);
875 	int set_context =	(oldsbsec->flags & CONTEXT_MNT);
876 	int set_rootcontext =	(oldsbsec->flags & ROOTCONTEXT_MNT);
877 
878 	/*
879 	 * if the parent was able to be mounted it clearly had no special lsm
880 	 * mount options.  thus we can safely deal with this superblock later
881 	 */
882 	if (!selinux_initialized(&selinux_state))
883 		return 0;
884 
885 	/*
886 	 * Specifying internal flags without providing a place to
887 	 * place the results is not allowed.
888 	 */
889 	if (kern_flags && !set_kern_flags)
890 		return -EINVAL;
891 
892 	/* how can we clone if the old one wasn't set up?? */
893 	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
894 
895 	/* if fs is reusing a sb, make sure that the contexts match */
896 	if (newsbsec->flags & SE_SBINITIALIZED) {
897 		if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
898 			*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
899 		return selinux_cmp_sb_context(oldsb, newsb);
900 	}
901 
902 	mutex_lock(&newsbsec->lock);
903 
904 	newsbsec->flags = oldsbsec->flags;
905 
906 	newsbsec->sid = oldsbsec->sid;
907 	newsbsec->def_sid = oldsbsec->def_sid;
908 	newsbsec->behavior = oldsbsec->behavior;
909 
910 	if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
911 		!(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
912 		rc = security_fs_use(&selinux_state, newsb);
913 		if (rc)
914 			goto out;
915 	}
916 
917 	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
918 		newsbsec->behavior = SECURITY_FS_USE_NATIVE;
919 		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
920 	}
921 
922 	if (set_context) {
923 		u32 sid = oldsbsec->mntpoint_sid;
924 
925 		if (!set_fscontext)
926 			newsbsec->sid = sid;
927 		if (!set_rootcontext) {
928 			struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
929 			newisec->sid = sid;
930 		}
931 		newsbsec->mntpoint_sid = sid;
932 	}
933 	if (set_rootcontext) {
934 		const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
935 		struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
936 
937 		newisec->sid = oldisec->sid;
938 	}
939 
940 	sb_finish_set_opts(newsb);
941 out:
942 	mutex_unlock(&newsbsec->lock);
943 	return rc;
944 }
945 
946 static int selinux_add_opt(int token, const char *s, void **mnt_opts)
947 {
948 	struct selinux_mnt_opts *opts = *mnt_opts;
949 
950 	if (token == Opt_seclabel)	/* eaten and completely ignored */
951 		return 0;
952 
953 	if (!opts) {
954 		opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
955 		if (!opts)
956 			return -ENOMEM;
957 		*mnt_opts = opts;
958 	}
959 	if (!s)
960 		return -ENOMEM;
961 	switch (token) {
962 	case Opt_context:
963 		if (opts->context || opts->defcontext)
964 			goto Einval;
965 		opts->context = s;
966 		break;
967 	case Opt_fscontext:
968 		if (opts->fscontext)
969 			goto Einval;
970 		opts->fscontext = s;
971 		break;
972 	case Opt_rootcontext:
973 		if (opts->rootcontext)
974 			goto Einval;
975 		opts->rootcontext = s;
976 		break;
977 	case Opt_defcontext:
978 		if (opts->context || opts->defcontext)
979 			goto Einval;
980 		opts->defcontext = s;
981 		break;
982 	}
983 	return 0;
984 Einval:
985 	pr_warn(SEL_MOUNT_FAIL_MSG);
986 	return -EINVAL;
987 }
988 
989 static int selinux_add_mnt_opt(const char *option, const char *val, int len,
990 			       void **mnt_opts)
991 {
992 	int token = Opt_error;
993 	int rc, i;
994 
995 	for (i = 0; i < ARRAY_SIZE(tokens); i++) {
996 		if (strcmp(option, tokens[i].name) == 0) {
997 			token = tokens[i].opt;
998 			break;
999 		}
1000 	}
1001 
1002 	if (token == Opt_error)
1003 		return -EINVAL;
1004 
1005 	if (token != Opt_seclabel) {
1006 		val = kmemdup_nul(val, len, GFP_KERNEL);
1007 		if (!val) {
1008 			rc = -ENOMEM;
1009 			goto free_opt;
1010 		}
1011 	}
1012 	rc = selinux_add_opt(token, val, mnt_opts);
1013 	if (unlikely(rc)) {
1014 		kfree(val);
1015 		goto free_opt;
1016 	}
1017 	return rc;
1018 
1019 free_opt:
1020 	if (*mnt_opts) {
1021 		selinux_free_mnt_opts(*mnt_opts);
1022 		*mnt_opts = NULL;
1023 	}
1024 	return rc;
1025 }
1026 
1027 static int show_sid(struct seq_file *m, u32 sid)
1028 {
1029 	char *context = NULL;
1030 	u32 len;
1031 	int rc;
1032 
1033 	rc = security_sid_to_context(&selinux_state, sid,
1034 					     &context, &len);
1035 	if (!rc) {
1036 		bool has_comma = context && strchr(context, ',');
1037 
1038 		seq_putc(m, '=');
1039 		if (has_comma)
1040 			seq_putc(m, '\"');
1041 		seq_escape(m, context, "\"\n\\");
1042 		if (has_comma)
1043 			seq_putc(m, '\"');
1044 	}
1045 	kfree(context);
1046 	return rc;
1047 }
1048 
1049 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1050 {
1051 	struct superblock_security_struct *sbsec = sb->s_security;
1052 	int rc;
1053 
1054 	if (!(sbsec->flags & SE_SBINITIALIZED))
1055 		return 0;
1056 
1057 	if (!selinux_initialized(&selinux_state))
1058 		return 0;
1059 
1060 	if (sbsec->flags & FSCONTEXT_MNT) {
1061 		seq_putc(m, ',');
1062 		seq_puts(m, FSCONTEXT_STR);
1063 		rc = show_sid(m, sbsec->sid);
1064 		if (rc)
1065 			return rc;
1066 	}
1067 	if (sbsec->flags & CONTEXT_MNT) {
1068 		seq_putc(m, ',');
1069 		seq_puts(m, CONTEXT_STR);
1070 		rc = show_sid(m, sbsec->mntpoint_sid);
1071 		if (rc)
1072 			return rc;
1073 	}
1074 	if (sbsec->flags & DEFCONTEXT_MNT) {
1075 		seq_putc(m, ',');
1076 		seq_puts(m, DEFCONTEXT_STR);
1077 		rc = show_sid(m, sbsec->def_sid);
1078 		if (rc)
1079 			return rc;
1080 	}
1081 	if (sbsec->flags & ROOTCONTEXT_MNT) {
1082 		struct dentry *root = sbsec->sb->s_root;
1083 		struct inode_security_struct *isec = backing_inode_security(root);
1084 		seq_putc(m, ',');
1085 		seq_puts(m, ROOTCONTEXT_STR);
1086 		rc = show_sid(m, isec->sid);
1087 		if (rc)
1088 			return rc;
1089 	}
1090 	if (sbsec->flags & SBLABEL_MNT) {
1091 		seq_putc(m, ',');
1092 		seq_puts(m, SECLABEL_STR);
1093 	}
1094 	return 0;
1095 }
1096 
1097 static inline u16 inode_mode_to_security_class(umode_t mode)
1098 {
1099 	switch (mode & S_IFMT) {
1100 	case S_IFSOCK:
1101 		return SECCLASS_SOCK_FILE;
1102 	case S_IFLNK:
1103 		return SECCLASS_LNK_FILE;
1104 	case S_IFREG:
1105 		return SECCLASS_FILE;
1106 	case S_IFBLK:
1107 		return SECCLASS_BLK_FILE;
1108 	case S_IFDIR:
1109 		return SECCLASS_DIR;
1110 	case S_IFCHR:
1111 		return SECCLASS_CHR_FILE;
1112 	case S_IFIFO:
1113 		return SECCLASS_FIFO_FILE;
1114 
1115 	}
1116 
1117 	return SECCLASS_FILE;
1118 }
1119 
1120 static inline int default_protocol_stream(int protocol)
1121 {
1122 	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1123 }
1124 
1125 static inline int default_protocol_dgram(int protocol)
1126 {
1127 	return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1128 }
1129 
1130 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1131 {
1132 	int extsockclass = selinux_policycap_extsockclass();
1133 
1134 	switch (family) {
1135 	case PF_UNIX:
1136 		switch (type) {
1137 		case SOCK_STREAM:
1138 		case SOCK_SEQPACKET:
1139 			return SECCLASS_UNIX_STREAM_SOCKET;
1140 		case SOCK_DGRAM:
1141 		case SOCK_RAW:
1142 			return SECCLASS_UNIX_DGRAM_SOCKET;
1143 		}
1144 		break;
1145 	case PF_INET:
1146 	case PF_INET6:
1147 		switch (type) {
1148 		case SOCK_STREAM:
1149 		case SOCK_SEQPACKET:
1150 			if (default_protocol_stream(protocol))
1151 				return SECCLASS_TCP_SOCKET;
1152 			else if (extsockclass && protocol == IPPROTO_SCTP)
1153 				return SECCLASS_SCTP_SOCKET;
1154 			else
1155 				return SECCLASS_RAWIP_SOCKET;
1156 		case SOCK_DGRAM:
1157 			if (default_protocol_dgram(protocol))
1158 				return SECCLASS_UDP_SOCKET;
1159 			else if (extsockclass && (protocol == IPPROTO_ICMP ||
1160 						  protocol == IPPROTO_ICMPV6))
1161 				return SECCLASS_ICMP_SOCKET;
1162 			else
1163 				return SECCLASS_RAWIP_SOCKET;
1164 		case SOCK_DCCP:
1165 			return SECCLASS_DCCP_SOCKET;
1166 		default:
1167 			return SECCLASS_RAWIP_SOCKET;
1168 		}
1169 		break;
1170 	case PF_NETLINK:
1171 		switch (protocol) {
1172 		case NETLINK_ROUTE:
1173 			return SECCLASS_NETLINK_ROUTE_SOCKET;
1174 		case NETLINK_SOCK_DIAG:
1175 			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1176 		case NETLINK_NFLOG:
1177 			return SECCLASS_NETLINK_NFLOG_SOCKET;
1178 		case NETLINK_XFRM:
1179 			return SECCLASS_NETLINK_XFRM_SOCKET;
1180 		case NETLINK_SELINUX:
1181 			return SECCLASS_NETLINK_SELINUX_SOCKET;
1182 		case NETLINK_ISCSI:
1183 			return SECCLASS_NETLINK_ISCSI_SOCKET;
1184 		case NETLINK_AUDIT:
1185 			return SECCLASS_NETLINK_AUDIT_SOCKET;
1186 		case NETLINK_FIB_LOOKUP:
1187 			return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1188 		case NETLINK_CONNECTOR:
1189 			return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1190 		case NETLINK_NETFILTER:
1191 			return SECCLASS_NETLINK_NETFILTER_SOCKET;
1192 		case NETLINK_DNRTMSG:
1193 			return SECCLASS_NETLINK_DNRT_SOCKET;
1194 		case NETLINK_KOBJECT_UEVENT:
1195 			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1196 		case NETLINK_GENERIC:
1197 			return SECCLASS_NETLINK_GENERIC_SOCKET;
1198 		case NETLINK_SCSITRANSPORT:
1199 			return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1200 		case NETLINK_RDMA:
1201 			return SECCLASS_NETLINK_RDMA_SOCKET;
1202 		case NETLINK_CRYPTO:
1203 			return SECCLASS_NETLINK_CRYPTO_SOCKET;
1204 		default:
1205 			return SECCLASS_NETLINK_SOCKET;
1206 		}
1207 	case PF_PACKET:
1208 		return SECCLASS_PACKET_SOCKET;
1209 	case PF_KEY:
1210 		return SECCLASS_KEY_SOCKET;
1211 	case PF_APPLETALK:
1212 		return SECCLASS_APPLETALK_SOCKET;
1213 	}
1214 
1215 	if (extsockclass) {
1216 		switch (family) {
1217 		case PF_AX25:
1218 			return SECCLASS_AX25_SOCKET;
1219 		case PF_IPX:
1220 			return SECCLASS_IPX_SOCKET;
1221 		case PF_NETROM:
1222 			return SECCLASS_NETROM_SOCKET;
1223 		case PF_ATMPVC:
1224 			return SECCLASS_ATMPVC_SOCKET;
1225 		case PF_X25:
1226 			return SECCLASS_X25_SOCKET;
1227 		case PF_ROSE:
1228 			return SECCLASS_ROSE_SOCKET;
1229 		case PF_DECnet:
1230 			return SECCLASS_DECNET_SOCKET;
1231 		case PF_ATMSVC:
1232 			return SECCLASS_ATMSVC_SOCKET;
1233 		case PF_RDS:
1234 			return SECCLASS_RDS_SOCKET;
1235 		case PF_IRDA:
1236 			return SECCLASS_IRDA_SOCKET;
1237 		case PF_PPPOX:
1238 			return SECCLASS_PPPOX_SOCKET;
1239 		case PF_LLC:
1240 			return SECCLASS_LLC_SOCKET;
1241 		case PF_CAN:
1242 			return SECCLASS_CAN_SOCKET;
1243 		case PF_TIPC:
1244 			return SECCLASS_TIPC_SOCKET;
1245 		case PF_BLUETOOTH:
1246 			return SECCLASS_BLUETOOTH_SOCKET;
1247 		case PF_IUCV:
1248 			return SECCLASS_IUCV_SOCKET;
1249 		case PF_RXRPC:
1250 			return SECCLASS_RXRPC_SOCKET;
1251 		case PF_ISDN:
1252 			return SECCLASS_ISDN_SOCKET;
1253 		case PF_PHONET:
1254 			return SECCLASS_PHONET_SOCKET;
1255 		case PF_IEEE802154:
1256 			return SECCLASS_IEEE802154_SOCKET;
1257 		case PF_CAIF:
1258 			return SECCLASS_CAIF_SOCKET;
1259 		case PF_ALG:
1260 			return SECCLASS_ALG_SOCKET;
1261 		case PF_NFC:
1262 			return SECCLASS_NFC_SOCKET;
1263 		case PF_VSOCK:
1264 			return SECCLASS_VSOCK_SOCKET;
1265 		case PF_KCM:
1266 			return SECCLASS_KCM_SOCKET;
1267 		case PF_QIPCRTR:
1268 			return SECCLASS_QIPCRTR_SOCKET;
1269 		case PF_SMC:
1270 			return SECCLASS_SMC_SOCKET;
1271 		case PF_XDP:
1272 			return SECCLASS_XDP_SOCKET;
1273 #if PF_MAX > 45
1274 #error New address family defined, please update this function.
1275 #endif
1276 		}
1277 	}
1278 
1279 	return SECCLASS_SOCKET;
1280 }
1281 
1282 static int selinux_genfs_get_sid(struct dentry *dentry,
1283 				 u16 tclass,
1284 				 u16 flags,
1285 				 u32 *sid)
1286 {
1287 	int rc;
1288 	struct super_block *sb = dentry->d_sb;
1289 	char *buffer, *path;
1290 
1291 	buffer = (char *)__get_free_page(GFP_KERNEL);
1292 	if (!buffer)
1293 		return -ENOMEM;
1294 
1295 	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1296 	if (IS_ERR(path))
1297 		rc = PTR_ERR(path);
1298 	else {
1299 		if (flags & SE_SBPROC) {
1300 			/* each process gets a /proc/PID/ entry. Strip off the
1301 			 * PID part to get a valid selinux labeling.
1302 			 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1303 			while (path[1] >= '0' && path[1] <= '9') {
1304 				path[1] = '/';
1305 				path++;
1306 			}
1307 		}
1308 		rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1309 					path, tclass, sid);
1310 		if (rc == -ENOENT) {
1311 			/* No match in policy, mark as unlabeled. */
1312 			*sid = SECINITSID_UNLABELED;
1313 			rc = 0;
1314 		}
1315 	}
1316 	free_page((unsigned long)buffer);
1317 	return rc;
1318 }
1319 
1320 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1321 				  u32 def_sid, u32 *sid)
1322 {
1323 #define INITCONTEXTLEN 255
1324 	char *context;
1325 	unsigned int len;
1326 	int rc;
1327 
1328 	len = INITCONTEXTLEN;
1329 	context = kmalloc(len + 1, GFP_NOFS);
1330 	if (!context)
1331 		return -ENOMEM;
1332 
1333 	context[len] = '\0';
1334 	rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1335 	if (rc == -ERANGE) {
1336 		kfree(context);
1337 
1338 		/* Need a larger buffer.  Query for the right size. */
1339 		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1340 		if (rc < 0)
1341 			return rc;
1342 
1343 		len = rc;
1344 		context = kmalloc(len + 1, GFP_NOFS);
1345 		if (!context)
1346 			return -ENOMEM;
1347 
1348 		context[len] = '\0';
1349 		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1350 				    context, len);
1351 	}
1352 	if (rc < 0) {
1353 		kfree(context);
1354 		if (rc != -ENODATA) {
1355 			pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
1356 				__func__, -rc, inode->i_sb->s_id, inode->i_ino);
1357 			return rc;
1358 		}
1359 		*sid = def_sid;
1360 		return 0;
1361 	}
1362 
1363 	rc = security_context_to_sid_default(&selinux_state, context, rc, sid,
1364 					     def_sid, GFP_NOFS);
1365 	if (rc) {
1366 		char *dev = inode->i_sb->s_id;
1367 		unsigned long ino = inode->i_ino;
1368 
1369 		if (rc == -EINVAL) {
1370 			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",
1371 					      ino, dev, context);
1372 		} else {
1373 			pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1374 				__func__, context, -rc, dev, ino);
1375 		}
1376 	}
1377 	kfree(context);
1378 	return 0;
1379 }
1380 
1381 /* The inode's security attributes must be initialized before first use. */
1382 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1383 {
1384 	struct superblock_security_struct *sbsec = NULL;
1385 	struct inode_security_struct *isec = selinux_inode(inode);
1386 	u32 task_sid, sid = 0;
1387 	u16 sclass;
1388 	struct dentry *dentry;
1389 	int rc = 0;
1390 
1391 	if (isec->initialized == LABEL_INITIALIZED)
1392 		return 0;
1393 
1394 	spin_lock(&isec->lock);
1395 	if (isec->initialized == LABEL_INITIALIZED)
1396 		goto out_unlock;
1397 
1398 	if (isec->sclass == SECCLASS_FILE)
1399 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
1400 
1401 	sbsec = inode->i_sb->s_security;
1402 	if (!(sbsec->flags & SE_SBINITIALIZED)) {
1403 		/* Defer initialization until selinux_complete_init,
1404 		   after the initial policy is loaded and the security
1405 		   server is ready to handle calls. */
1406 		spin_lock(&sbsec->isec_lock);
1407 		if (list_empty(&isec->list))
1408 			list_add(&isec->list, &sbsec->isec_head);
1409 		spin_unlock(&sbsec->isec_lock);
1410 		goto out_unlock;
1411 	}
1412 
1413 	sclass = isec->sclass;
1414 	task_sid = isec->task_sid;
1415 	sid = isec->sid;
1416 	isec->initialized = LABEL_PENDING;
1417 	spin_unlock(&isec->lock);
1418 
1419 	switch (sbsec->behavior) {
1420 	case SECURITY_FS_USE_NATIVE:
1421 		break;
1422 	case SECURITY_FS_USE_XATTR:
1423 		if (!(inode->i_opflags & IOP_XATTR)) {
1424 			sid = sbsec->def_sid;
1425 			break;
1426 		}
1427 		/* Need a dentry, since the xattr API requires one.
1428 		   Life would be simpler if we could just pass the inode. */
1429 		if (opt_dentry) {
1430 			/* Called from d_instantiate or d_splice_alias. */
1431 			dentry = dget(opt_dentry);
1432 		} else {
1433 			/*
1434 			 * Called from selinux_complete_init, try to find a dentry.
1435 			 * Some filesystems really want a connected one, so try
1436 			 * that first.  We could split SECURITY_FS_USE_XATTR in
1437 			 * two, depending upon that...
1438 			 */
1439 			dentry = d_find_alias(inode);
1440 			if (!dentry)
1441 				dentry = d_find_any_alias(inode);
1442 		}
1443 		if (!dentry) {
1444 			/*
1445 			 * this is can be hit on boot when a file is accessed
1446 			 * before the policy is loaded.  When we load policy we
1447 			 * may find inodes that have no dentry on the
1448 			 * sbsec->isec_head list.  No reason to complain as these
1449 			 * will get fixed up the next time we go through
1450 			 * inode_doinit with a dentry, before these inodes could
1451 			 * be used again by userspace.
1452 			 */
1453 			goto out;
1454 		}
1455 
1456 		rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1457 					    &sid);
1458 		dput(dentry);
1459 		if (rc)
1460 			goto out;
1461 		break;
1462 	case SECURITY_FS_USE_TASK:
1463 		sid = task_sid;
1464 		break;
1465 	case SECURITY_FS_USE_TRANS:
1466 		/* Default to the fs SID. */
1467 		sid = sbsec->sid;
1468 
1469 		/* Try to obtain a transition SID. */
1470 		rc = security_transition_sid(&selinux_state, task_sid, sid,
1471 					     sclass, NULL, &sid);
1472 		if (rc)
1473 			goto out;
1474 		break;
1475 	case SECURITY_FS_USE_MNTPOINT:
1476 		sid = sbsec->mntpoint_sid;
1477 		break;
1478 	default:
1479 		/* Default to the fs superblock SID. */
1480 		sid = sbsec->sid;
1481 
1482 		if ((sbsec->flags & SE_SBGENFS) &&
1483 		     (!S_ISLNK(inode->i_mode) ||
1484 		      selinux_policycap_genfs_seclabel_symlinks())) {
1485 			/* We must have a dentry to determine the label on
1486 			 * procfs inodes */
1487 			if (opt_dentry) {
1488 				/* Called from d_instantiate or
1489 				 * d_splice_alias. */
1490 				dentry = dget(opt_dentry);
1491 			} else {
1492 				/* Called from selinux_complete_init, try to
1493 				 * find a dentry.  Some filesystems really want
1494 				 * a connected one, so try that first.
1495 				 */
1496 				dentry = d_find_alias(inode);
1497 				if (!dentry)
1498 					dentry = d_find_any_alias(inode);
1499 			}
1500 			/*
1501 			 * This can be hit on boot when a file is accessed
1502 			 * before the policy is loaded.  When we load policy we
1503 			 * may find inodes that have no dentry on the
1504 			 * sbsec->isec_head list.  No reason to complain as
1505 			 * these will get fixed up the next time we go through
1506 			 * inode_doinit() with a dentry, before these inodes
1507 			 * could be used again by userspace.
1508 			 */
1509 			if (!dentry)
1510 				goto out;
1511 			rc = selinux_genfs_get_sid(dentry, sclass,
1512 						   sbsec->flags, &sid);
1513 			if (rc) {
1514 				dput(dentry);
1515 				goto out;
1516 			}
1517 
1518 			if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1519 			    (inode->i_opflags & IOP_XATTR)) {
1520 				rc = inode_doinit_use_xattr(inode, dentry,
1521 							    sid, &sid);
1522 				if (rc) {
1523 					dput(dentry);
1524 					goto out;
1525 				}
1526 			}
1527 			dput(dentry);
1528 		}
1529 		break;
1530 	}
1531 
1532 out:
1533 	spin_lock(&isec->lock);
1534 	if (isec->initialized == LABEL_PENDING) {
1535 		if (!sid || rc) {
1536 			isec->initialized = LABEL_INVALID;
1537 			goto out_unlock;
1538 		}
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 
1549 /* Convert a Linux signal to an access vector. */
1550 static inline u32 signal_to_av(int sig)
1551 {
1552 	u32 perm = 0;
1553 
1554 	switch (sig) {
1555 	case SIGCHLD:
1556 		/* Commonly granted from child to parent. */
1557 		perm = PROCESS__SIGCHLD;
1558 		break;
1559 	case SIGKILL:
1560 		/* Cannot be caught or ignored */
1561 		perm = PROCESS__SIGKILL;
1562 		break;
1563 	case SIGSTOP:
1564 		/* Cannot be caught or ignored */
1565 		perm = PROCESS__SIGSTOP;
1566 		break;
1567 	default:
1568 		/* All other signals. */
1569 		perm = PROCESS__SIGNAL;
1570 		break;
1571 	}
1572 
1573 	return perm;
1574 }
1575 
1576 #if CAP_LAST_CAP > 63
1577 #error Fix SELinux to handle capabilities > 63.
1578 #endif
1579 
1580 /* Check whether a task is allowed to use a capability. */
1581 static int cred_has_capability(const struct cred *cred,
1582 			       int cap, unsigned int opts, bool initns)
1583 {
1584 	struct common_audit_data ad;
1585 	struct av_decision avd;
1586 	u16 sclass;
1587 	u32 sid = cred_sid(cred);
1588 	u32 av = CAP_TO_MASK(cap);
1589 	int rc;
1590 
1591 	ad.type = LSM_AUDIT_DATA_CAP;
1592 	ad.u.cap = cap;
1593 
1594 	switch (CAP_TO_INDEX(cap)) {
1595 	case 0:
1596 		sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1597 		break;
1598 	case 1:
1599 		sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1600 		break;
1601 	default:
1602 		pr_err("SELinux:  out of range capability %d\n", cap);
1603 		BUG();
1604 		return -EINVAL;
1605 	}
1606 
1607 	rc = avc_has_perm_noaudit(&selinux_state,
1608 				  sid, sid, sclass, av, 0, &avd);
1609 	if (!(opts & CAP_OPT_NOAUDIT)) {
1610 		int rc2 = avc_audit(&selinux_state,
1611 				    sid, sid, sclass, av, &avd, rc, &ad, 0);
1612 		if (rc2)
1613 			return rc2;
1614 	}
1615 	return rc;
1616 }
1617 
1618 /* Check whether a task has a particular permission to an inode.
1619    The 'adp' parameter is optional and allows other audit
1620    data to be passed (e.g. the dentry). */
1621 static int inode_has_perm(const struct cred *cred,
1622 			  struct inode *inode,
1623 			  u32 perms,
1624 			  struct common_audit_data *adp)
1625 {
1626 	struct inode_security_struct *isec;
1627 	u32 sid;
1628 
1629 	validate_creds(cred);
1630 
1631 	if (unlikely(IS_PRIVATE(inode)))
1632 		return 0;
1633 
1634 	sid = cred_sid(cred);
1635 	isec = selinux_inode(inode);
1636 
1637 	return avc_has_perm(&selinux_state,
1638 			    sid, isec->sid, isec->sclass, perms, adp);
1639 }
1640 
1641 /* Same as inode_has_perm, but pass explicit audit data containing
1642    the dentry to help the auditing code to more easily generate the
1643    pathname if needed. */
1644 static inline int dentry_has_perm(const struct cred *cred,
1645 				  struct dentry *dentry,
1646 				  u32 av)
1647 {
1648 	struct inode *inode = d_backing_inode(dentry);
1649 	struct common_audit_data ad;
1650 
1651 	ad.type = LSM_AUDIT_DATA_DENTRY;
1652 	ad.u.dentry = dentry;
1653 	__inode_security_revalidate(inode, dentry, true);
1654 	return inode_has_perm(cred, inode, av, &ad);
1655 }
1656 
1657 /* Same as inode_has_perm, but pass explicit audit data containing
1658    the path to help the auditing code to more easily generate the
1659    pathname if needed. */
1660 static inline int path_has_perm(const struct cred *cred,
1661 				const struct path *path,
1662 				u32 av)
1663 {
1664 	struct inode *inode = d_backing_inode(path->dentry);
1665 	struct common_audit_data ad;
1666 
1667 	ad.type = LSM_AUDIT_DATA_PATH;
1668 	ad.u.path = *path;
1669 	__inode_security_revalidate(inode, path->dentry, true);
1670 	return inode_has_perm(cred, inode, av, &ad);
1671 }
1672 
1673 /* Same as path_has_perm, but uses the inode from the file struct. */
1674 static inline int file_path_has_perm(const struct cred *cred,
1675 				     struct file *file,
1676 				     u32 av)
1677 {
1678 	struct common_audit_data ad;
1679 
1680 	ad.type = LSM_AUDIT_DATA_FILE;
1681 	ad.u.file = file;
1682 	return inode_has_perm(cred, file_inode(file), av, &ad);
1683 }
1684 
1685 #ifdef CONFIG_BPF_SYSCALL
1686 static int bpf_fd_pass(struct file *file, u32 sid);
1687 #endif
1688 
1689 /* Check whether a task can use an open file descriptor to
1690    access an inode in a given way.  Check access to the
1691    descriptor itself, and then use dentry_has_perm to
1692    check a particular permission to the file.
1693    Access to the descriptor is implicitly granted if it
1694    has the same SID as the process.  If av is zero, then
1695    access to the file is not checked, e.g. for cases
1696    where only the descriptor is affected like seek. */
1697 static int file_has_perm(const struct cred *cred,
1698 			 struct file *file,
1699 			 u32 av)
1700 {
1701 	struct file_security_struct *fsec = selinux_file(file);
1702 	struct inode *inode = file_inode(file);
1703 	struct common_audit_data ad;
1704 	u32 sid = cred_sid(cred);
1705 	int rc;
1706 
1707 	ad.type = LSM_AUDIT_DATA_FILE;
1708 	ad.u.file = file;
1709 
1710 	if (sid != fsec->sid) {
1711 		rc = avc_has_perm(&selinux_state,
1712 				  sid, fsec->sid,
1713 				  SECCLASS_FD,
1714 				  FD__USE,
1715 				  &ad);
1716 		if (rc)
1717 			goto out;
1718 	}
1719 
1720 #ifdef CONFIG_BPF_SYSCALL
1721 	rc = bpf_fd_pass(file, cred_sid(cred));
1722 	if (rc)
1723 		return rc;
1724 #endif
1725 
1726 	/* av is zero if only checking access to the descriptor. */
1727 	rc = 0;
1728 	if (av)
1729 		rc = inode_has_perm(cred, inode, av, &ad);
1730 
1731 out:
1732 	return rc;
1733 }
1734 
1735 /*
1736  * Determine the label for an inode that might be unioned.
1737  */
1738 static int
1739 selinux_determine_inode_label(const struct task_security_struct *tsec,
1740 				 struct inode *dir,
1741 				 const struct qstr *name, u16 tclass,
1742 				 u32 *_new_isid)
1743 {
1744 	const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1745 
1746 	if ((sbsec->flags & SE_SBINITIALIZED) &&
1747 	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1748 		*_new_isid = sbsec->mntpoint_sid;
1749 	} else if ((sbsec->flags & SBLABEL_MNT) &&
1750 		   tsec->create_sid) {
1751 		*_new_isid = tsec->create_sid;
1752 	} else {
1753 		const struct inode_security_struct *dsec = inode_security(dir);
1754 		return security_transition_sid(&selinux_state, tsec->sid,
1755 					       dsec->sid, tclass,
1756 					       name, _new_isid);
1757 	}
1758 
1759 	return 0;
1760 }
1761 
1762 /* Check whether a task can create a file. */
1763 static int may_create(struct inode *dir,
1764 		      struct dentry *dentry,
1765 		      u16 tclass)
1766 {
1767 	const struct task_security_struct *tsec = selinux_cred(current_cred());
1768 	struct inode_security_struct *dsec;
1769 	struct superblock_security_struct *sbsec;
1770 	u32 sid, newsid;
1771 	struct common_audit_data ad;
1772 	int rc;
1773 
1774 	dsec = inode_security(dir);
1775 	sbsec = dir->i_sb->s_security;
1776 
1777 	sid = tsec->sid;
1778 
1779 	ad.type = LSM_AUDIT_DATA_DENTRY;
1780 	ad.u.dentry = dentry;
1781 
1782 	rc = avc_has_perm(&selinux_state,
1783 			  sid, dsec->sid, SECCLASS_DIR,
1784 			  DIR__ADD_NAME | DIR__SEARCH,
1785 			  &ad);
1786 	if (rc)
1787 		return rc;
1788 
1789 	rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1790 					   &newsid);
1791 	if (rc)
1792 		return rc;
1793 
1794 	rc = avc_has_perm(&selinux_state,
1795 			  sid, newsid, tclass, FILE__CREATE, &ad);
1796 	if (rc)
1797 		return rc;
1798 
1799 	return avc_has_perm(&selinux_state,
1800 			    newsid, sbsec->sid,
1801 			    SECCLASS_FILESYSTEM,
1802 			    FILESYSTEM__ASSOCIATE, &ad);
1803 }
1804 
1805 #define MAY_LINK	0
1806 #define MAY_UNLINK	1
1807 #define MAY_RMDIR	2
1808 
1809 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1810 static int may_link(struct inode *dir,
1811 		    struct dentry *dentry,
1812 		    int kind)
1813 
1814 {
1815 	struct inode_security_struct *dsec, *isec;
1816 	struct common_audit_data ad;
1817 	u32 sid = current_sid();
1818 	u32 av;
1819 	int rc;
1820 
1821 	dsec = inode_security(dir);
1822 	isec = backing_inode_security(dentry);
1823 
1824 	ad.type = LSM_AUDIT_DATA_DENTRY;
1825 	ad.u.dentry = dentry;
1826 
1827 	av = DIR__SEARCH;
1828 	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1829 	rc = avc_has_perm(&selinux_state,
1830 			  sid, dsec->sid, SECCLASS_DIR, av, &ad);
1831 	if (rc)
1832 		return rc;
1833 
1834 	switch (kind) {
1835 	case MAY_LINK:
1836 		av = FILE__LINK;
1837 		break;
1838 	case MAY_UNLINK:
1839 		av = FILE__UNLINK;
1840 		break;
1841 	case MAY_RMDIR:
1842 		av = DIR__RMDIR;
1843 		break;
1844 	default:
1845 		pr_warn("SELinux: %s:  unrecognized kind %d\n",
1846 			__func__, kind);
1847 		return 0;
1848 	}
1849 
1850 	rc = avc_has_perm(&selinux_state,
1851 			  sid, isec->sid, isec->sclass, av, &ad);
1852 	return rc;
1853 }
1854 
1855 static inline int may_rename(struct inode *old_dir,
1856 			     struct dentry *old_dentry,
1857 			     struct inode *new_dir,
1858 			     struct dentry *new_dentry)
1859 {
1860 	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1861 	struct common_audit_data ad;
1862 	u32 sid = current_sid();
1863 	u32 av;
1864 	int old_is_dir, new_is_dir;
1865 	int rc;
1866 
1867 	old_dsec = inode_security(old_dir);
1868 	old_isec = backing_inode_security(old_dentry);
1869 	old_is_dir = d_is_dir(old_dentry);
1870 	new_dsec = inode_security(new_dir);
1871 
1872 	ad.type = LSM_AUDIT_DATA_DENTRY;
1873 
1874 	ad.u.dentry = old_dentry;
1875 	rc = avc_has_perm(&selinux_state,
1876 			  sid, old_dsec->sid, SECCLASS_DIR,
1877 			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1878 	if (rc)
1879 		return rc;
1880 	rc = avc_has_perm(&selinux_state,
1881 			  sid, old_isec->sid,
1882 			  old_isec->sclass, FILE__RENAME, &ad);
1883 	if (rc)
1884 		return rc;
1885 	if (old_is_dir && new_dir != old_dir) {
1886 		rc = avc_has_perm(&selinux_state,
1887 				  sid, old_isec->sid,
1888 				  old_isec->sclass, DIR__REPARENT, &ad);
1889 		if (rc)
1890 			return rc;
1891 	}
1892 
1893 	ad.u.dentry = new_dentry;
1894 	av = DIR__ADD_NAME | DIR__SEARCH;
1895 	if (d_is_positive(new_dentry))
1896 		av |= DIR__REMOVE_NAME;
1897 	rc = avc_has_perm(&selinux_state,
1898 			  sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1899 	if (rc)
1900 		return rc;
1901 	if (d_is_positive(new_dentry)) {
1902 		new_isec = backing_inode_security(new_dentry);
1903 		new_is_dir = d_is_dir(new_dentry);
1904 		rc = avc_has_perm(&selinux_state,
1905 				  sid, new_isec->sid,
1906 				  new_isec->sclass,
1907 				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1908 		if (rc)
1909 			return rc;
1910 	}
1911 
1912 	return 0;
1913 }
1914 
1915 /* Check whether a task can perform a filesystem operation. */
1916 static int superblock_has_perm(const struct cred *cred,
1917 			       struct super_block *sb,
1918 			       u32 perms,
1919 			       struct common_audit_data *ad)
1920 {
1921 	struct superblock_security_struct *sbsec;
1922 	u32 sid = cred_sid(cred);
1923 
1924 	sbsec = sb->s_security;
1925 	return avc_has_perm(&selinux_state,
1926 			    sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1927 }
1928 
1929 /* Convert a Linux mode and permission mask to an access vector. */
1930 static inline u32 file_mask_to_av(int mode, int mask)
1931 {
1932 	u32 av = 0;
1933 
1934 	if (!S_ISDIR(mode)) {
1935 		if (mask & MAY_EXEC)
1936 			av |= FILE__EXECUTE;
1937 		if (mask & MAY_READ)
1938 			av |= FILE__READ;
1939 
1940 		if (mask & MAY_APPEND)
1941 			av |= FILE__APPEND;
1942 		else if (mask & MAY_WRITE)
1943 			av |= FILE__WRITE;
1944 
1945 	} else {
1946 		if (mask & MAY_EXEC)
1947 			av |= DIR__SEARCH;
1948 		if (mask & MAY_WRITE)
1949 			av |= DIR__WRITE;
1950 		if (mask & MAY_READ)
1951 			av |= DIR__READ;
1952 	}
1953 
1954 	return av;
1955 }
1956 
1957 /* Convert a Linux file to an access vector. */
1958 static inline u32 file_to_av(struct file *file)
1959 {
1960 	u32 av = 0;
1961 
1962 	if (file->f_mode & FMODE_READ)
1963 		av |= FILE__READ;
1964 	if (file->f_mode & FMODE_WRITE) {
1965 		if (file->f_flags & O_APPEND)
1966 			av |= FILE__APPEND;
1967 		else
1968 			av |= FILE__WRITE;
1969 	}
1970 	if (!av) {
1971 		/*
1972 		 * Special file opened with flags 3 for ioctl-only use.
1973 		 */
1974 		av = FILE__IOCTL;
1975 	}
1976 
1977 	return av;
1978 }
1979 
1980 /*
1981  * Convert a file to an access vector and include the correct open
1982  * open permission.
1983  */
1984 static inline u32 open_file_to_av(struct file *file)
1985 {
1986 	u32 av = file_to_av(file);
1987 	struct inode *inode = file_inode(file);
1988 
1989 	if (selinux_policycap_openperm() &&
1990 	    inode->i_sb->s_magic != SOCKFS_MAGIC)
1991 		av |= FILE__OPEN;
1992 
1993 	return av;
1994 }
1995 
1996 /* Hook functions begin here. */
1997 
1998 static int selinux_binder_set_context_mgr(struct task_struct *mgr)
1999 {
2000 	u32 mysid = current_sid();
2001 	u32 mgrsid = task_sid(mgr);
2002 
2003 	return avc_has_perm(&selinux_state,
2004 			    mysid, mgrsid, SECCLASS_BINDER,
2005 			    BINDER__SET_CONTEXT_MGR, NULL);
2006 }
2007 
2008 static int selinux_binder_transaction(struct task_struct *from,
2009 				      struct task_struct *to)
2010 {
2011 	u32 mysid = current_sid();
2012 	u32 fromsid = task_sid(from);
2013 	u32 tosid = task_sid(to);
2014 	int rc;
2015 
2016 	if (mysid != fromsid) {
2017 		rc = avc_has_perm(&selinux_state,
2018 				  mysid, fromsid, SECCLASS_BINDER,
2019 				  BINDER__IMPERSONATE, NULL);
2020 		if (rc)
2021 			return rc;
2022 	}
2023 
2024 	return avc_has_perm(&selinux_state,
2025 			    fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2026 			    NULL);
2027 }
2028 
2029 static int selinux_binder_transfer_binder(struct task_struct *from,
2030 					  struct task_struct *to)
2031 {
2032 	u32 fromsid = task_sid(from);
2033 	u32 tosid = task_sid(to);
2034 
2035 	return avc_has_perm(&selinux_state,
2036 			    fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2037 			    NULL);
2038 }
2039 
2040 static int selinux_binder_transfer_file(struct task_struct *from,
2041 					struct task_struct *to,
2042 					struct file *file)
2043 {
2044 	u32 sid = task_sid(to);
2045 	struct file_security_struct *fsec = selinux_file(file);
2046 	struct dentry *dentry = file->f_path.dentry;
2047 	struct inode_security_struct *isec;
2048 	struct common_audit_data ad;
2049 	int rc;
2050 
2051 	ad.type = LSM_AUDIT_DATA_PATH;
2052 	ad.u.path = file->f_path;
2053 
2054 	if (sid != fsec->sid) {
2055 		rc = avc_has_perm(&selinux_state,
2056 				  sid, fsec->sid,
2057 				  SECCLASS_FD,
2058 				  FD__USE,
2059 				  &ad);
2060 		if (rc)
2061 			return rc;
2062 	}
2063 
2064 #ifdef CONFIG_BPF_SYSCALL
2065 	rc = bpf_fd_pass(file, sid);
2066 	if (rc)
2067 		return rc;
2068 #endif
2069 
2070 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2071 		return 0;
2072 
2073 	isec = backing_inode_security(dentry);
2074 	return avc_has_perm(&selinux_state,
2075 			    sid, isec->sid, isec->sclass, file_to_av(file),
2076 			    &ad);
2077 }
2078 
2079 static int selinux_ptrace_access_check(struct task_struct *child,
2080 				     unsigned int mode)
2081 {
2082 	u32 sid = current_sid();
2083 	u32 csid = task_sid(child);
2084 
2085 	if (mode & PTRACE_MODE_READ)
2086 		return avc_has_perm(&selinux_state,
2087 				    sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2088 
2089 	return avc_has_perm(&selinux_state,
2090 			    sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2091 }
2092 
2093 static int selinux_ptrace_traceme(struct task_struct *parent)
2094 {
2095 	return avc_has_perm(&selinux_state,
2096 			    task_sid(parent), current_sid(), SECCLASS_PROCESS,
2097 			    PROCESS__PTRACE, NULL);
2098 }
2099 
2100 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2101 			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
2102 {
2103 	return avc_has_perm(&selinux_state,
2104 			    current_sid(), task_sid(target), SECCLASS_PROCESS,
2105 			    PROCESS__GETCAP, NULL);
2106 }
2107 
2108 static int selinux_capset(struct cred *new, const struct cred *old,
2109 			  const kernel_cap_t *effective,
2110 			  const kernel_cap_t *inheritable,
2111 			  const kernel_cap_t *permitted)
2112 {
2113 	return avc_has_perm(&selinux_state,
2114 			    cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2115 			    PROCESS__SETCAP, NULL);
2116 }
2117 
2118 /*
2119  * (This comment used to live with the selinux_task_setuid hook,
2120  * which was removed).
2121  *
2122  * Since setuid only affects the current process, and since the SELinux
2123  * controls are not based on the Linux identity attributes, SELinux does not
2124  * need to control this operation.  However, SELinux does control the use of
2125  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2126  */
2127 
2128 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2129 			   int cap, unsigned int opts)
2130 {
2131 	return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2132 }
2133 
2134 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2135 {
2136 	const struct cred *cred = current_cred();
2137 	int rc = 0;
2138 
2139 	if (!sb)
2140 		return 0;
2141 
2142 	switch (cmds) {
2143 	case Q_SYNC:
2144 	case Q_QUOTAON:
2145 	case Q_QUOTAOFF:
2146 	case Q_SETINFO:
2147 	case Q_SETQUOTA:
2148 	case Q_XQUOTAOFF:
2149 	case Q_XQUOTAON:
2150 	case Q_XSETQLIM:
2151 		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2152 		break;
2153 	case Q_GETFMT:
2154 	case Q_GETINFO:
2155 	case Q_GETQUOTA:
2156 	case Q_XGETQUOTA:
2157 	case Q_XGETQSTAT:
2158 	case Q_XGETQSTATV:
2159 	case Q_XGETNEXTQUOTA:
2160 		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2161 		break;
2162 	default:
2163 		rc = 0;  /* let the kernel handle invalid cmds */
2164 		break;
2165 	}
2166 	return rc;
2167 }
2168 
2169 static int selinux_quota_on(struct dentry *dentry)
2170 {
2171 	const struct cred *cred = current_cred();
2172 
2173 	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2174 }
2175 
2176 static int selinux_syslog(int type)
2177 {
2178 	switch (type) {
2179 	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
2180 	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2181 		return avc_has_perm(&selinux_state,
2182 				    current_sid(), SECINITSID_KERNEL,
2183 				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2184 	case SYSLOG_ACTION_CONSOLE_OFF:	/* Disable logging to console */
2185 	case SYSLOG_ACTION_CONSOLE_ON:	/* Enable logging to console */
2186 	/* Set level of messages printed to console */
2187 	case SYSLOG_ACTION_CONSOLE_LEVEL:
2188 		return avc_has_perm(&selinux_state,
2189 				    current_sid(), SECINITSID_KERNEL,
2190 				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2191 				    NULL);
2192 	}
2193 	/* All other syslog types */
2194 	return avc_has_perm(&selinux_state,
2195 			    current_sid(), SECINITSID_KERNEL,
2196 			    SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2197 }
2198 
2199 /*
2200  * Check that a process has enough memory to allocate a new virtual
2201  * mapping. 0 means there is enough memory for the allocation to
2202  * succeed and -ENOMEM implies there is not.
2203  *
2204  * Do not audit the selinux permission check, as this is applied to all
2205  * processes that allocate mappings.
2206  */
2207 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2208 {
2209 	int rc, cap_sys_admin = 0;
2210 
2211 	rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2212 				 CAP_OPT_NOAUDIT, true);
2213 	if (rc == 0)
2214 		cap_sys_admin = 1;
2215 
2216 	return cap_sys_admin;
2217 }
2218 
2219 /* binprm security operations */
2220 
2221 static u32 ptrace_parent_sid(void)
2222 {
2223 	u32 sid = 0;
2224 	struct task_struct *tracer;
2225 
2226 	rcu_read_lock();
2227 	tracer = ptrace_parent(current);
2228 	if (tracer)
2229 		sid = task_sid(tracer);
2230 	rcu_read_unlock();
2231 
2232 	return sid;
2233 }
2234 
2235 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2236 			    const struct task_security_struct *old_tsec,
2237 			    const struct task_security_struct *new_tsec)
2238 {
2239 	int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2240 	int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2241 	int rc;
2242 	u32 av;
2243 
2244 	if (!nnp && !nosuid)
2245 		return 0; /* neither NNP nor nosuid */
2246 
2247 	if (new_tsec->sid == old_tsec->sid)
2248 		return 0; /* No change in credentials */
2249 
2250 	/*
2251 	 * If the policy enables the nnp_nosuid_transition policy capability,
2252 	 * then we permit transitions under NNP or nosuid if the
2253 	 * policy allows the corresponding permission between
2254 	 * the old and new contexts.
2255 	 */
2256 	if (selinux_policycap_nnp_nosuid_transition()) {
2257 		av = 0;
2258 		if (nnp)
2259 			av |= PROCESS2__NNP_TRANSITION;
2260 		if (nosuid)
2261 			av |= PROCESS2__NOSUID_TRANSITION;
2262 		rc = avc_has_perm(&selinux_state,
2263 				  old_tsec->sid, new_tsec->sid,
2264 				  SECCLASS_PROCESS2, av, NULL);
2265 		if (!rc)
2266 			return 0;
2267 	}
2268 
2269 	/*
2270 	 * We also permit NNP or nosuid transitions to bounded SIDs,
2271 	 * i.e. SIDs that are guaranteed to only be allowed a subset
2272 	 * of the permissions of the current SID.
2273 	 */
2274 	rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2275 					 new_tsec->sid);
2276 	if (!rc)
2277 		return 0;
2278 
2279 	/*
2280 	 * On failure, preserve the errno values for NNP vs nosuid.
2281 	 * NNP:  Operation not permitted for caller.
2282 	 * nosuid:  Permission denied to file.
2283 	 */
2284 	if (nnp)
2285 		return -EPERM;
2286 	return -EACCES;
2287 }
2288 
2289 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2290 {
2291 	const struct task_security_struct *old_tsec;
2292 	struct task_security_struct *new_tsec;
2293 	struct inode_security_struct *isec;
2294 	struct common_audit_data ad;
2295 	struct inode *inode = file_inode(bprm->file);
2296 	int rc;
2297 
2298 	/* SELinux context only depends on initial program or script and not
2299 	 * the script interpreter */
2300 
2301 	old_tsec = selinux_cred(current_cred());
2302 	new_tsec = selinux_cred(bprm->cred);
2303 	isec = inode_security(inode);
2304 
2305 	/* Default to the current task SID. */
2306 	new_tsec->sid = old_tsec->sid;
2307 	new_tsec->osid = old_tsec->sid;
2308 
2309 	/* Reset fs, key, and sock SIDs on execve. */
2310 	new_tsec->create_sid = 0;
2311 	new_tsec->keycreate_sid = 0;
2312 	new_tsec->sockcreate_sid = 0;
2313 
2314 	if (old_tsec->exec_sid) {
2315 		new_tsec->sid = old_tsec->exec_sid;
2316 		/* Reset exec SID on execve. */
2317 		new_tsec->exec_sid = 0;
2318 
2319 		/* Fail on NNP or nosuid if not an allowed transition. */
2320 		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2321 		if (rc)
2322 			return rc;
2323 	} else {
2324 		/* Check for a default transition on this program. */
2325 		rc = security_transition_sid(&selinux_state, old_tsec->sid,
2326 					     isec->sid, SECCLASS_PROCESS, NULL,
2327 					     &new_tsec->sid);
2328 		if (rc)
2329 			return rc;
2330 
2331 		/*
2332 		 * Fallback to old SID on NNP or nosuid if not an allowed
2333 		 * transition.
2334 		 */
2335 		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2336 		if (rc)
2337 			new_tsec->sid = old_tsec->sid;
2338 	}
2339 
2340 	ad.type = LSM_AUDIT_DATA_FILE;
2341 	ad.u.file = bprm->file;
2342 
2343 	if (new_tsec->sid == old_tsec->sid) {
2344 		rc = avc_has_perm(&selinux_state,
2345 				  old_tsec->sid, isec->sid,
2346 				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2347 		if (rc)
2348 			return rc;
2349 	} else {
2350 		/* Check permissions for the transition. */
2351 		rc = avc_has_perm(&selinux_state,
2352 				  old_tsec->sid, new_tsec->sid,
2353 				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2354 		if (rc)
2355 			return rc;
2356 
2357 		rc = avc_has_perm(&selinux_state,
2358 				  new_tsec->sid, isec->sid,
2359 				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2360 		if (rc)
2361 			return rc;
2362 
2363 		/* Check for shared state */
2364 		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2365 			rc = avc_has_perm(&selinux_state,
2366 					  old_tsec->sid, new_tsec->sid,
2367 					  SECCLASS_PROCESS, PROCESS__SHARE,
2368 					  NULL);
2369 			if (rc)
2370 				return -EPERM;
2371 		}
2372 
2373 		/* Make sure that anyone attempting to ptrace over a task that
2374 		 * changes its SID has the appropriate permit */
2375 		if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2376 			u32 ptsid = ptrace_parent_sid();
2377 			if (ptsid != 0) {
2378 				rc = avc_has_perm(&selinux_state,
2379 						  ptsid, new_tsec->sid,
2380 						  SECCLASS_PROCESS,
2381 						  PROCESS__PTRACE, NULL);
2382 				if (rc)
2383 					return -EPERM;
2384 			}
2385 		}
2386 
2387 		/* Clear any possibly unsafe personality bits on exec: */
2388 		bprm->per_clear |= PER_CLEAR_ON_SETID;
2389 
2390 		/* Enable secure mode for SIDs transitions unless
2391 		   the noatsecure permission is granted between
2392 		   the two SIDs, i.e. ahp returns 0. */
2393 		rc = avc_has_perm(&selinux_state,
2394 				  old_tsec->sid, new_tsec->sid,
2395 				  SECCLASS_PROCESS, PROCESS__NOATSECURE,
2396 				  NULL);
2397 		bprm->secureexec |= !!rc;
2398 	}
2399 
2400 	return 0;
2401 }
2402 
2403 static int match_file(const void *p, struct file *file, unsigned fd)
2404 {
2405 	return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2406 }
2407 
2408 /* Derived from fs/exec.c:flush_old_files. */
2409 static inline void flush_unauthorized_files(const struct cred *cred,
2410 					    struct files_struct *files)
2411 {
2412 	struct file *file, *devnull = NULL;
2413 	struct tty_struct *tty;
2414 	int drop_tty = 0;
2415 	unsigned n;
2416 
2417 	tty = get_current_tty();
2418 	if (tty) {
2419 		spin_lock(&tty->files_lock);
2420 		if (!list_empty(&tty->tty_files)) {
2421 			struct tty_file_private *file_priv;
2422 
2423 			/* Revalidate access to controlling tty.
2424 			   Use file_path_has_perm on the tty path directly
2425 			   rather than using file_has_perm, as this particular
2426 			   open file may belong to another process and we are
2427 			   only interested in the inode-based check here. */
2428 			file_priv = list_first_entry(&tty->tty_files,
2429 						struct tty_file_private, list);
2430 			file = file_priv->file;
2431 			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2432 				drop_tty = 1;
2433 		}
2434 		spin_unlock(&tty->files_lock);
2435 		tty_kref_put(tty);
2436 	}
2437 	/* Reset controlling tty. */
2438 	if (drop_tty)
2439 		no_tty();
2440 
2441 	/* Revalidate access to inherited open files. */
2442 	n = iterate_fd(files, 0, match_file, cred);
2443 	if (!n) /* none found? */
2444 		return;
2445 
2446 	devnull = dentry_open(&selinux_null, O_RDWR, cred);
2447 	if (IS_ERR(devnull))
2448 		devnull = NULL;
2449 	/* replace all the matching ones with this */
2450 	do {
2451 		replace_fd(n - 1, devnull, 0);
2452 	} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2453 	if (devnull)
2454 		fput(devnull);
2455 }
2456 
2457 /*
2458  * Prepare a process for imminent new credential changes due to exec
2459  */
2460 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2461 {
2462 	struct task_security_struct *new_tsec;
2463 	struct rlimit *rlim, *initrlim;
2464 	int rc, i;
2465 
2466 	new_tsec = selinux_cred(bprm->cred);
2467 	if (new_tsec->sid == new_tsec->osid)
2468 		return;
2469 
2470 	/* Close files for which the new task SID is not authorized. */
2471 	flush_unauthorized_files(bprm->cred, current->files);
2472 
2473 	/* Always clear parent death signal on SID transitions. */
2474 	current->pdeath_signal = 0;
2475 
2476 	/* Check whether the new SID can inherit resource limits from the old
2477 	 * SID.  If not, reset all soft limits to the lower of the current
2478 	 * task's hard limit and the init task's soft limit.
2479 	 *
2480 	 * Note that the setting of hard limits (even to lower them) can be
2481 	 * controlled by the setrlimit check.  The inclusion of the init task's
2482 	 * soft limit into the computation is to avoid resetting soft limits
2483 	 * higher than the default soft limit for cases where the default is
2484 	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2485 	 */
2486 	rc = avc_has_perm(&selinux_state,
2487 			  new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2488 			  PROCESS__RLIMITINH, NULL);
2489 	if (rc) {
2490 		/* protect against do_prlimit() */
2491 		task_lock(current);
2492 		for (i = 0; i < RLIM_NLIMITS; i++) {
2493 			rlim = current->signal->rlim + i;
2494 			initrlim = init_task.signal->rlim + i;
2495 			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2496 		}
2497 		task_unlock(current);
2498 		if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2499 			update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2500 	}
2501 }
2502 
2503 /*
2504  * Clean up the process immediately after the installation of new credentials
2505  * due to exec
2506  */
2507 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2508 {
2509 	const struct task_security_struct *tsec = selinux_cred(current_cred());
2510 	u32 osid, sid;
2511 	int rc;
2512 
2513 	osid = tsec->osid;
2514 	sid = tsec->sid;
2515 
2516 	if (sid == osid)
2517 		return;
2518 
2519 	/* Check whether the new SID can inherit signal state from the old SID.
2520 	 * If not, clear itimers to avoid subsequent signal generation and
2521 	 * flush and unblock signals.
2522 	 *
2523 	 * This must occur _after_ the task SID has been updated so that any
2524 	 * kill done after the flush will be checked against the new SID.
2525 	 */
2526 	rc = avc_has_perm(&selinux_state,
2527 			  osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2528 	if (rc) {
2529 		clear_itimer();
2530 
2531 		spin_lock_irq(&current->sighand->siglock);
2532 		if (!fatal_signal_pending(current)) {
2533 			flush_sigqueue(&current->pending);
2534 			flush_sigqueue(&current->signal->shared_pending);
2535 			flush_signal_handlers(current, 1);
2536 			sigemptyset(&current->blocked);
2537 			recalc_sigpending();
2538 		}
2539 		spin_unlock_irq(&current->sighand->siglock);
2540 	}
2541 
2542 	/* Wake up the parent if it is waiting so that it can recheck
2543 	 * wait permission to the new task SID. */
2544 	read_lock(&tasklist_lock);
2545 	__wake_up_parent(current, current->real_parent);
2546 	read_unlock(&tasklist_lock);
2547 }
2548 
2549 /* superblock security operations */
2550 
2551 static int selinux_sb_alloc_security(struct super_block *sb)
2552 {
2553 	struct superblock_security_struct *sbsec;
2554 
2555 	sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
2556 	if (!sbsec)
2557 		return -ENOMEM;
2558 
2559 	mutex_init(&sbsec->lock);
2560 	INIT_LIST_HEAD(&sbsec->isec_head);
2561 	spin_lock_init(&sbsec->isec_lock);
2562 	sbsec->sb = sb;
2563 	sbsec->sid = SECINITSID_UNLABELED;
2564 	sbsec->def_sid = SECINITSID_FILE;
2565 	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2566 	sb->s_security = sbsec;
2567 
2568 	return 0;
2569 }
2570 
2571 static void selinux_sb_free_security(struct super_block *sb)
2572 {
2573 	superblock_free_security(sb);
2574 }
2575 
2576 static inline int opt_len(const char *s)
2577 {
2578 	bool open_quote = false;
2579 	int len;
2580 	char c;
2581 
2582 	for (len = 0; (c = s[len]) != '\0'; len++) {
2583 		if (c == '"')
2584 			open_quote = !open_quote;
2585 		if (c == ',' && !open_quote)
2586 			break;
2587 	}
2588 	return len;
2589 }
2590 
2591 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2592 {
2593 	char *from = options;
2594 	char *to = options;
2595 	bool first = true;
2596 	int rc;
2597 
2598 	while (1) {
2599 		int len = opt_len(from);
2600 		int token;
2601 		char *arg = NULL;
2602 
2603 		token = match_opt_prefix(from, len, &arg);
2604 
2605 		if (token != Opt_error) {
2606 			char *p, *q;
2607 
2608 			/* strip quotes */
2609 			if (arg) {
2610 				for (p = q = arg; p < from + len; p++) {
2611 					char c = *p;
2612 					if (c != '"')
2613 						*q++ = c;
2614 				}
2615 				arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2616 				if (!arg) {
2617 					rc = -ENOMEM;
2618 					goto free_opt;
2619 				}
2620 			}
2621 			rc = selinux_add_opt(token, arg, mnt_opts);
2622 			if (unlikely(rc)) {
2623 				kfree(arg);
2624 				goto free_opt;
2625 			}
2626 		} else {
2627 			if (!first) {	// copy with preceding comma
2628 				from--;
2629 				len++;
2630 			}
2631 			if (to != from)
2632 				memmove(to, from, len);
2633 			to += len;
2634 			first = false;
2635 		}
2636 		if (!from[len])
2637 			break;
2638 		from += len + 1;
2639 	}
2640 	*to = '\0';
2641 	return 0;
2642 
2643 free_opt:
2644 	if (*mnt_opts) {
2645 		selinux_free_mnt_opts(*mnt_opts);
2646 		*mnt_opts = NULL;
2647 	}
2648 	return rc;
2649 }
2650 
2651 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2652 {
2653 	struct selinux_mnt_opts *opts = mnt_opts;
2654 	struct superblock_security_struct *sbsec = sb->s_security;
2655 	u32 sid;
2656 	int rc;
2657 
2658 	if (!(sbsec->flags & SE_SBINITIALIZED))
2659 		return 0;
2660 
2661 	if (!opts)
2662 		return 0;
2663 
2664 	if (opts->fscontext) {
2665 		rc = parse_sid(sb, opts->fscontext, &sid);
2666 		if (rc)
2667 			return rc;
2668 		if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2669 			goto out_bad_option;
2670 	}
2671 	if (opts->context) {
2672 		rc = parse_sid(sb, opts->context, &sid);
2673 		if (rc)
2674 			return rc;
2675 		if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2676 			goto out_bad_option;
2677 	}
2678 	if (opts->rootcontext) {
2679 		struct inode_security_struct *root_isec;
2680 		root_isec = backing_inode_security(sb->s_root);
2681 		rc = parse_sid(sb, opts->rootcontext, &sid);
2682 		if (rc)
2683 			return rc;
2684 		if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2685 			goto out_bad_option;
2686 	}
2687 	if (opts->defcontext) {
2688 		rc = parse_sid(sb, opts->defcontext, &sid);
2689 		if (rc)
2690 			return rc;
2691 		if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2692 			goto out_bad_option;
2693 	}
2694 	return 0;
2695 
2696 out_bad_option:
2697 	pr_warn("SELinux: unable to change security options "
2698 	       "during remount (dev %s, type=%s)\n", sb->s_id,
2699 	       sb->s_type->name);
2700 	return -EINVAL;
2701 }
2702 
2703 static int selinux_sb_kern_mount(struct super_block *sb)
2704 {
2705 	const struct cred *cred = current_cred();
2706 	struct common_audit_data ad;
2707 
2708 	ad.type = LSM_AUDIT_DATA_DENTRY;
2709 	ad.u.dentry = sb->s_root;
2710 	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2711 }
2712 
2713 static int selinux_sb_statfs(struct dentry *dentry)
2714 {
2715 	const struct cred *cred = current_cred();
2716 	struct common_audit_data ad;
2717 
2718 	ad.type = LSM_AUDIT_DATA_DENTRY;
2719 	ad.u.dentry = dentry->d_sb->s_root;
2720 	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2721 }
2722 
2723 static int selinux_mount(const char *dev_name,
2724 			 const struct path *path,
2725 			 const char *type,
2726 			 unsigned long flags,
2727 			 void *data)
2728 {
2729 	const struct cred *cred = current_cred();
2730 
2731 	if (flags & MS_REMOUNT)
2732 		return superblock_has_perm(cred, path->dentry->d_sb,
2733 					   FILESYSTEM__REMOUNT, NULL);
2734 	else
2735 		return path_has_perm(cred, path, FILE__MOUNTON);
2736 }
2737 
2738 static int selinux_move_mount(const struct path *from_path,
2739 			      const struct path *to_path)
2740 {
2741 	const struct cred *cred = current_cred();
2742 
2743 	return path_has_perm(cred, to_path, FILE__MOUNTON);
2744 }
2745 
2746 static int selinux_umount(struct vfsmount *mnt, int flags)
2747 {
2748 	const struct cred *cred = current_cred();
2749 
2750 	return superblock_has_perm(cred, mnt->mnt_sb,
2751 				   FILESYSTEM__UNMOUNT, NULL);
2752 }
2753 
2754 static int selinux_fs_context_dup(struct fs_context *fc,
2755 				  struct fs_context *src_fc)
2756 {
2757 	const struct selinux_mnt_opts *src = src_fc->security;
2758 	struct selinux_mnt_opts *opts;
2759 
2760 	if (!src)
2761 		return 0;
2762 
2763 	fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
2764 	if (!fc->security)
2765 		return -ENOMEM;
2766 
2767 	opts = fc->security;
2768 
2769 	if (src->fscontext) {
2770 		opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL);
2771 		if (!opts->fscontext)
2772 			return -ENOMEM;
2773 	}
2774 	if (src->context) {
2775 		opts->context = kstrdup(src->context, GFP_KERNEL);
2776 		if (!opts->context)
2777 			return -ENOMEM;
2778 	}
2779 	if (src->rootcontext) {
2780 		opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL);
2781 		if (!opts->rootcontext)
2782 			return -ENOMEM;
2783 	}
2784 	if (src->defcontext) {
2785 		opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL);
2786 		if (!opts->defcontext)
2787 			return -ENOMEM;
2788 	}
2789 	return 0;
2790 }
2791 
2792 static const struct fs_parameter_spec selinux_fs_parameters[] = {
2793 	fsparam_string(CONTEXT_STR,	Opt_context),
2794 	fsparam_string(DEFCONTEXT_STR,	Opt_defcontext),
2795 	fsparam_string(FSCONTEXT_STR,	Opt_fscontext),
2796 	fsparam_string(ROOTCONTEXT_STR,	Opt_rootcontext),
2797 	fsparam_flag  (SECLABEL_STR,	Opt_seclabel),
2798 	{}
2799 };
2800 
2801 static int selinux_fs_context_parse_param(struct fs_context *fc,
2802 					  struct fs_parameter *param)
2803 {
2804 	struct fs_parse_result result;
2805 	int opt, rc;
2806 
2807 	opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2808 	if (opt < 0)
2809 		return opt;
2810 
2811 	rc = selinux_add_opt(opt, param->string, &fc->security);
2812 	if (!rc) {
2813 		param->string = NULL;
2814 		rc = 1;
2815 	}
2816 	return rc;
2817 }
2818 
2819 /* inode security operations */
2820 
2821 static int selinux_inode_alloc_security(struct inode *inode)
2822 {
2823 	struct inode_security_struct *isec = selinux_inode(inode);
2824 	u32 sid = current_sid();
2825 
2826 	spin_lock_init(&isec->lock);
2827 	INIT_LIST_HEAD(&isec->list);
2828 	isec->inode = inode;
2829 	isec->sid = SECINITSID_UNLABELED;
2830 	isec->sclass = SECCLASS_FILE;
2831 	isec->task_sid = sid;
2832 	isec->initialized = LABEL_INVALID;
2833 
2834 	return 0;
2835 }
2836 
2837 static void selinux_inode_free_security(struct inode *inode)
2838 {
2839 	inode_free_security(inode);
2840 }
2841 
2842 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2843 					const struct qstr *name, void **ctx,
2844 					u32 *ctxlen)
2845 {
2846 	u32 newsid;
2847 	int rc;
2848 
2849 	rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2850 					   d_inode(dentry->d_parent), name,
2851 					   inode_mode_to_security_class(mode),
2852 					   &newsid);
2853 	if (rc)
2854 		return rc;
2855 
2856 	return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
2857 				       ctxlen);
2858 }
2859 
2860 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2861 					  struct qstr *name,
2862 					  const struct cred *old,
2863 					  struct cred *new)
2864 {
2865 	u32 newsid;
2866 	int rc;
2867 	struct task_security_struct *tsec;
2868 
2869 	rc = selinux_determine_inode_label(selinux_cred(old),
2870 					   d_inode(dentry->d_parent), name,
2871 					   inode_mode_to_security_class(mode),
2872 					   &newsid);
2873 	if (rc)
2874 		return rc;
2875 
2876 	tsec = selinux_cred(new);
2877 	tsec->create_sid = newsid;
2878 	return 0;
2879 }
2880 
2881 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2882 				       const struct qstr *qstr,
2883 				       const char **name,
2884 				       void **value, size_t *len)
2885 {
2886 	const struct task_security_struct *tsec = selinux_cred(current_cred());
2887 	struct superblock_security_struct *sbsec;
2888 	u32 newsid, clen;
2889 	int rc;
2890 	char *context;
2891 
2892 	sbsec = dir->i_sb->s_security;
2893 
2894 	newsid = tsec->create_sid;
2895 
2896 	rc = selinux_determine_inode_label(tsec, dir, qstr,
2897 		inode_mode_to_security_class(inode->i_mode),
2898 		&newsid);
2899 	if (rc)
2900 		return rc;
2901 
2902 	/* Possibly defer initialization to selinux_complete_init. */
2903 	if (sbsec->flags & SE_SBINITIALIZED) {
2904 		struct inode_security_struct *isec = selinux_inode(inode);
2905 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
2906 		isec->sid = newsid;
2907 		isec->initialized = LABEL_INITIALIZED;
2908 	}
2909 
2910 	if (!selinux_initialized(&selinux_state) ||
2911 	    !(sbsec->flags & SBLABEL_MNT))
2912 		return -EOPNOTSUPP;
2913 
2914 	if (name)
2915 		*name = XATTR_SELINUX_SUFFIX;
2916 
2917 	if (value && len) {
2918 		rc = security_sid_to_context_force(&selinux_state, newsid,
2919 						   &context, &clen);
2920 		if (rc)
2921 			return rc;
2922 		*value = context;
2923 		*len = clen;
2924 	}
2925 
2926 	return 0;
2927 }
2928 
2929 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2930 {
2931 	return may_create(dir, dentry, SECCLASS_FILE);
2932 }
2933 
2934 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2935 {
2936 	return may_link(dir, old_dentry, MAY_LINK);
2937 }
2938 
2939 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2940 {
2941 	return may_link(dir, dentry, MAY_UNLINK);
2942 }
2943 
2944 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2945 {
2946 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
2947 }
2948 
2949 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2950 {
2951 	return may_create(dir, dentry, SECCLASS_DIR);
2952 }
2953 
2954 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2955 {
2956 	return may_link(dir, dentry, MAY_RMDIR);
2957 }
2958 
2959 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2960 {
2961 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
2962 }
2963 
2964 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2965 				struct inode *new_inode, struct dentry *new_dentry)
2966 {
2967 	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2968 }
2969 
2970 static int selinux_inode_readlink(struct dentry *dentry)
2971 {
2972 	const struct cred *cred = current_cred();
2973 
2974 	return dentry_has_perm(cred, dentry, FILE__READ);
2975 }
2976 
2977 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2978 				     bool rcu)
2979 {
2980 	const struct cred *cred = current_cred();
2981 	struct common_audit_data ad;
2982 	struct inode_security_struct *isec;
2983 	u32 sid;
2984 
2985 	validate_creds(cred);
2986 
2987 	ad.type = LSM_AUDIT_DATA_DENTRY;
2988 	ad.u.dentry = dentry;
2989 	sid = cred_sid(cred);
2990 	isec = inode_security_rcu(inode, rcu);
2991 	if (IS_ERR(isec))
2992 		return PTR_ERR(isec);
2993 
2994 	return avc_has_perm_flags(&selinux_state,
2995 				  sid, isec->sid, isec->sclass, FILE__READ, &ad,
2996 				  rcu ? MAY_NOT_BLOCK : 0);
2997 }
2998 
2999 static noinline int audit_inode_permission(struct inode *inode,
3000 					   u32 perms, u32 audited, u32 denied,
3001 					   int result)
3002 {
3003 	struct common_audit_data ad;
3004 	struct inode_security_struct *isec = selinux_inode(inode);
3005 	int rc;
3006 
3007 	ad.type = LSM_AUDIT_DATA_INODE;
3008 	ad.u.inode = inode;
3009 
3010 	rc = slow_avc_audit(&selinux_state,
3011 			    current_sid(), isec->sid, isec->sclass, perms,
3012 			    audited, denied, result, &ad);
3013 	if (rc)
3014 		return rc;
3015 	return 0;
3016 }
3017 
3018 static int selinux_inode_permission(struct inode *inode, int mask)
3019 {
3020 	const struct cred *cred = current_cred();
3021 	u32 perms;
3022 	bool from_access;
3023 	bool no_block = mask & MAY_NOT_BLOCK;
3024 	struct inode_security_struct *isec;
3025 	u32 sid;
3026 	struct av_decision avd;
3027 	int rc, rc2;
3028 	u32 audited, denied;
3029 
3030 	from_access = mask & MAY_ACCESS;
3031 	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3032 
3033 	/* No permission to check.  Existence test. */
3034 	if (!mask)
3035 		return 0;
3036 
3037 	validate_creds(cred);
3038 
3039 	if (unlikely(IS_PRIVATE(inode)))
3040 		return 0;
3041 
3042 	perms = file_mask_to_av(inode->i_mode, mask);
3043 
3044 	sid = cred_sid(cred);
3045 	isec = inode_security_rcu(inode, no_block);
3046 	if (IS_ERR(isec))
3047 		return PTR_ERR(isec);
3048 
3049 	rc = avc_has_perm_noaudit(&selinux_state,
3050 				  sid, isec->sid, isec->sclass, perms,
3051 				  no_block ? AVC_NONBLOCKING : 0,
3052 				  &avd);
3053 	audited = avc_audit_required(perms, &avd, rc,
3054 				     from_access ? FILE__AUDIT_ACCESS : 0,
3055 				     &denied);
3056 	if (likely(!audited))
3057 		return rc;
3058 
3059 	/* fall back to ref-walk if we have to generate audit */
3060 	if (no_block)
3061 		return -ECHILD;
3062 
3063 	rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3064 	if (rc2)
3065 		return rc2;
3066 	return rc;
3067 }
3068 
3069 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3070 {
3071 	const struct cred *cred = current_cred();
3072 	struct inode *inode = d_backing_inode(dentry);
3073 	unsigned int ia_valid = iattr->ia_valid;
3074 	__u32 av = FILE__WRITE;
3075 
3076 	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3077 	if (ia_valid & ATTR_FORCE) {
3078 		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3079 			      ATTR_FORCE);
3080 		if (!ia_valid)
3081 			return 0;
3082 	}
3083 
3084 	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3085 			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3086 		return dentry_has_perm(cred, dentry, FILE__SETATTR);
3087 
3088 	if (selinux_policycap_openperm() &&
3089 	    inode->i_sb->s_magic != SOCKFS_MAGIC &&
3090 	    (ia_valid & ATTR_SIZE) &&
3091 	    !(ia_valid & ATTR_FILE))
3092 		av |= FILE__OPEN;
3093 
3094 	return dentry_has_perm(cred, dentry, av);
3095 }
3096 
3097 static int selinux_inode_getattr(const struct path *path)
3098 {
3099 	return path_has_perm(current_cred(), path, FILE__GETATTR);
3100 }
3101 
3102 static bool has_cap_mac_admin(bool audit)
3103 {
3104 	const struct cred *cred = current_cred();
3105 	unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3106 
3107 	if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3108 		return false;
3109 	if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3110 		return false;
3111 	return true;
3112 }
3113 
3114 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3115 				  const void *value, size_t size, int flags)
3116 {
3117 	struct inode *inode = d_backing_inode(dentry);
3118 	struct inode_security_struct *isec;
3119 	struct superblock_security_struct *sbsec;
3120 	struct common_audit_data ad;
3121 	u32 newsid, sid = current_sid();
3122 	int rc = 0;
3123 
3124 	if (strcmp(name, XATTR_NAME_SELINUX)) {
3125 		rc = cap_inode_setxattr(dentry, name, value, size, flags);
3126 		if (rc)
3127 			return rc;
3128 
3129 		/* Not an attribute we recognize, so just check the
3130 		   ordinary setattr permission. */
3131 		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3132 	}
3133 
3134 	if (!selinux_initialized(&selinux_state))
3135 		return (inode_owner_or_capable(inode) ? 0 : -EPERM);
3136 
3137 	sbsec = inode->i_sb->s_security;
3138 	if (!(sbsec->flags & SBLABEL_MNT))
3139 		return -EOPNOTSUPP;
3140 
3141 	if (!inode_owner_or_capable(inode))
3142 		return -EPERM;
3143 
3144 	ad.type = LSM_AUDIT_DATA_DENTRY;
3145 	ad.u.dentry = dentry;
3146 
3147 	isec = backing_inode_security(dentry);
3148 	rc = avc_has_perm(&selinux_state,
3149 			  sid, isec->sid, isec->sclass,
3150 			  FILE__RELABELFROM, &ad);
3151 	if (rc)
3152 		return rc;
3153 
3154 	rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3155 				     GFP_KERNEL);
3156 	if (rc == -EINVAL) {
3157 		if (!has_cap_mac_admin(true)) {
3158 			struct audit_buffer *ab;
3159 			size_t audit_size;
3160 
3161 			/* We strip a nul only if it is at the end, otherwise the
3162 			 * context contains a nul and we should audit that */
3163 			if (value) {
3164 				const char *str = value;
3165 
3166 				if (str[size - 1] == '\0')
3167 					audit_size = size - 1;
3168 				else
3169 					audit_size = size;
3170 			} else {
3171 				audit_size = 0;
3172 			}
3173 			ab = audit_log_start(audit_context(),
3174 					     GFP_ATOMIC, AUDIT_SELINUX_ERR);
3175 			audit_log_format(ab, "op=setxattr invalid_context=");
3176 			audit_log_n_untrustedstring(ab, value, audit_size);
3177 			audit_log_end(ab);
3178 
3179 			return rc;
3180 		}
3181 		rc = security_context_to_sid_force(&selinux_state, value,
3182 						   size, &newsid);
3183 	}
3184 	if (rc)
3185 		return rc;
3186 
3187 	rc = avc_has_perm(&selinux_state,
3188 			  sid, newsid, isec->sclass,
3189 			  FILE__RELABELTO, &ad);
3190 	if (rc)
3191 		return rc;
3192 
3193 	rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3194 					  sid, isec->sclass);
3195 	if (rc)
3196 		return rc;
3197 
3198 	return avc_has_perm(&selinux_state,
3199 			    newsid,
3200 			    sbsec->sid,
3201 			    SECCLASS_FILESYSTEM,
3202 			    FILESYSTEM__ASSOCIATE,
3203 			    &ad);
3204 }
3205 
3206 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3207 					const void *value, size_t size,
3208 					int flags)
3209 {
3210 	struct inode *inode = d_backing_inode(dentry);
3211 	struct inode_security_struct *isec;
3212 	u32 newsid;
3213 	int rc;
3214 
3215 	if (strcmp(name, XATTR_NAME_SELINUX)) {
3216 		/* Not an attribute we recognize, so nothing to do. */
3217 		return;
3218 	}
3219 
3220 	if (!selinux_initialized(&selinux_state)) {
3221 		/* If we haven't even been initialized, then we can't validate
3222 		 * against a policy, so leave the label as invalid. It may
3223 		 * resolve to a valid label on the next revalidation try if
3224 		 * we've since initialized.
3225 		 */
3226 		return;
3227 	}
3228 
3229 	rc = security_context_to_sid_force(&selinux_state, value, size,
3230 					   &newsid);
3231 	if (rc) {
3232 		pr_err("SELinux:  unable to map context to SID"
3233 		       "for (%s, %lu), rc=%d\n",
3234 		       inode->i_sb->s_id, inode->i_ino, -rc);
3235 		return;
3236 	}
3237 
3238 	isec = backing_inode_security(dentry);
3239 	spin_lock(&isec->lock);
3240 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3241 	isec->sid = newsid;
3242 	isec->initialized = LABEL_INITIALIZED;
3243 	spin_unlock(&isec->lock);
3244 
3245 	return;
3246 }
3247 
3248 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3249 {
3250 	const struct cred *cred = current_cred();
3251 
3252 	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3253 }
3254 
3255 static int selinux_inode_listxattr(struct dentry *dentry)
3256 {
3257 	const struct cred *cred = current_cred();
3258 
3259 	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3260 }
3261 
3262 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3263 {
3264 	if (strcmp(name, XATTR_NAME_SELINUX)) {
3265 		int rc = cap_inode_removexattr(dentry, name);
3266 		if (rc)
3267 			return rc;
3268 
3269 		/* Not an attribute we recognize, so just check the
3270 		   ordinary setattr permission. */
3271 		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3272 	}
3273 
3274 	/* No one is allowed to remove a SELinux security label.
3275 	   You can change the label, but all data must be labeled. */
3276 	return -EACCES;
3277 }
3278 
3279 static int selinux_path_notify(const struct path *path, u64 mask,
3280 						unsigned int obj_type)
3281 {
3282 	int ret;
3283 	u32 perm;
3284 
3285 	struct common_audit_data ad;
3286 
3287 	ad.type = LSM_AUDIT_DATA_PATH;
3288 	ad.u.path = *path;
3289 
3290 	/*
3291 	 * Set permission needed based on the type of mark being set.
3292 	 * Performs an additional check for sb watches.
3293 	 */
3294 	switch (obj_type) {
3295 	case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3296 		perm = FILE__WATCH_MOUNT;
3297 		break;
3298 	case FSNOTIFY_OBJ_TYPE_SB:
3299 		perm = FILE__WATCH_SB;
3300 		ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3301 						FILESYSTEM__WATCH, &ad);
3302 		if (ret)
3303 			return ret;
3304 		break;
3305 	case FSNOTIFY_OBJ_TYPE_INODE:
3306 		perm = FILE__WATCH;
3307 		break;
3308 	default:
3309 		return -EINVAL;
3310 	}
3311 
3312 	/* blocking watches require the file:watch_with_perm permission */
3313 	if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3314 		perm |= FILE__WATCH_WITH_PERM;
3315 
3316 	/* watches on read-like events need the file:watch_reads permission */
3317 	if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3318 		perm |= FILE__WATCH_READS;
3319 
3320 	return path_has_perm(current_cred(), path, perm);
3321 }
3322 
3323 /*
3324  * Copy the inode security context value to the user.
3325  *
3326  * Permission check is handled by selinux_inode_getxattr hook.
3327  */
3328 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3329 {
3330 	u32 size;
3331 	int error;
3332 	char *context = NULL;
3333 	struct inode_security_struct *isec;
3334 
3335 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
3336 		return -EOPNOTSUPP;
3337 
3338 	/*
3339 	 * If the caller has CAP_MAC_ADMIN, then get the raw context
3340 	 * value even if it is not defined by current policy; otherwise,
3341 	 * use the in-core value under current policy.
3342 	 * Use the non-auditing forms of the permission checks since
3343 	 * getxattr may be called by unprivileged processes commonly
3344 	 * and lack of permission just means that we fall back to the
3345 	 * in-core context value, not a denial.
3346 	 */
3347 	isec = inode_security(inode);
3348 	if (has_cap_mac_admin(false))
3349 		error = security_sid_to_context_force(&selinux_state,
3350 						      isec->sid, &context,
3351 						      &size);
3352 	else
3353 		error = security_sid_to_context(&selinux_state, isec->sid,
3354 						&context, &size);
3355 	if (error)
3356 		return error;
3357 	error = size;
3358 	if (alloc) {
3359 		*buffer = context;
3360 		goto out_nofree;
3361 	}
3362 	kfree(context);
3363 out_nofree:
3364 	return error;
3365 }
3366 
3367 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3368 				     const void *value, size_t size, int flags)
3369 {
3370 	struct inode_security_struct *isec = inode_security_novalidate(inode);
3371 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
3372 	u32 newsid;
3373 	int rc;
3374 
3375 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
3376 		return -EOPNOTSUPP;
3377 
3378 	if (!(sbsec->flags & SBLABEL_MNT))
3379 		return -EOPNOTSUPP;
3380 
3381 	if (!value || !size)
3382 		return -EACCES;
3383 
3384 	rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3385 				     GFP_KERNEL);
3386 	if (rc)
3387 		return rc;
3388 
3389 	spin_lock(&isec->lock);
3390 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3391 	isec->sid = newsid;
3392 	isec->initialized = LABEL_INITIALIZED;
3393 	spin_unlock(&isec->lock);
3394 	return 0;
3395 }
3396 
3397 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3398 {
3399 	const int len = sizeof(XATTR_NAME_SELINUX);
3400 	if (buffer && len <= buffer_size)
3401 		memcpy(buffer, XATTR_NAME_SELINUX, len);
3402 	return len;
3403 }
3404 
3405 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3406 {
3407 	struct inode_security_struct *isec = inode_security_novalidate(inode);
3408 	*secid = isec->sid;
3409 }
3410 
3411 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3412 {
3413 	u32 sid;
3414 	struct task_security_struct *tsec;
3415 	struct cred *new_creds = *new;
3416 
3417 	if (new_creds == NULL) {
3418 		new_creds = prepare_creds();
3419 		if (!new_creds)
3420 			return -ENOMEM;
3421 	}
3422 
3423 	tsec = selinux_cred(new_creds);
3424 	/* Get label from overlay inode and set it in create_sid */
3425 	selinux_inode_getsecid(d_inode(src), &sid);
3426 	tsec->create_sid = sid;
3427 	*new = new_creds;
3428 	return 0;
3429 }
3430 
3431 static int selinux_inode_copy_up_xattr(const char *name)
3432 {
3433 	/* The copy_up hook above sets the initial context on an inode, but we
3434 	 * don't then want to overwrite it by blindly copying all the lower
3435 	 * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3436 	 */
3437 	if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3438 		return 1; /* Discard */
3439 	/*
3440 	 * Any other attribute apart from SELINUX is not claimed, supported
3441 	 * by selinux.
3442 	 */
3443 	return -EOPNOTSUPP;
3444 }
3445 
3446 /* kernfs node operations */
3447 
3448 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3449 					struct kernfs_node *kn)
3450 {
3451 	const struct task_security_struct *tsec = selinux_cred(current_cred());
3452 	u32 parent_sid, newsid, clen;
3453 	int rc;
3454 	char *context;
3455 
3456 	rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3457 	if (rc == -ENODATA)
3458 		return 0;
3459 	else if (rc < 0)
3460 		return rc;
3461 
3462 	clen = (u32)rc;
3463 	context = kmalloc(clen, GFP_KERNEL);
3464 	if (!context)
3465 		return -ENOMEM;
3466 
3467 	rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3468 	if (rc < 0) {
3469 		kfree(context);
3470 		return rc;
3471 	}
3472 
3473 	rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid,
3474 				     GFP_KERNEL);
3475 	kfree(context);
3476 	if (rc)
3477 		return rc;
3478 
3479 	if (tsec->create_sid) {
3480 		newsid = tsec->create_sid;
3481 	} else {
3482 		u16 secclass = inode_mode_to_security_class(kn->mode);
3483 		struct qstr q;
3484 
3485 		q.name = kn->name;
3486 		q.hash_len = hashlen_string(kn_dir, kn->name);
3487 
3488 		rc = security_transition_sid(&selinux_state, tsec->sid,
3489 					     parent_sid, secclass, &q,
3490 					     &newsid);
3491 		if (rc)
3492 			return rc;
3493 	}
3494 
3495 	rc = security_sid_to_context_force(&selinux_state, newsid,
3496 					   &context, &clen);
3497 	if (rc)
3498 		return rc;
3499 
3500 	rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3501 			      XATTR_CREATE);
3502 	kfree(context);
3503 	return rc;
3504 }
3505 
3506 
3507 /* file security operations */
3508 
3509 static int selinux_revalidate_file_permission(struct file *file, int mask)
3510 {
3511 	const struct cred *cred = current_cred();
3512 	struct inode *inode = file_inode(file);
3513 
3514 	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3515 	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3516 		mask |= MAY_APPEND;
3517 
3518 	return file_has_perm(cred, file,
3519 			     file_mask_to_av(inode->i_mode, mask));
3520 }
3521 
3522 static int selinux_file_permission(struct file *file, int mask)
3523 {
3524 	struct inode *inode = file_inode(file);
3525 	struct file_security_struct *fsec = selinux_file(file);
3526 	struct inode_security_struct *isec;
3527 	u32 sid = current_sid();
3528 
3529 	if (!mask)
3530 		/* No permission to check.  Existence test. */
3531 		return 0;
3532 
3533 	isec = inode_security(inode);
3534 	if (sid == fsec->sid && fsec->isid == isec->sid &&
3535 	    fsec->pseqno == avc_policy_seqno(&selinux_state))
3536 		/* No change since file_open check. */
3537 		return 0;
3538 
3539 	return selinux_revalidate_file_permission(file, mask);
3540 }
3541 
3542 static int selinux_file_alloc_security(struct file *file)
3543 {
3544 	struct file_security_struct *fsec = selinux_file(file);
3545 	u32 sid = current_sid();
3546 
3547 	fsec->sid = sid;
3548 	fsec->fown_sid = sid;
3549 
3550 	return 0;
3551 }
3552 
3553 /*
3554  * Check whether a task has the ioctl permission and cmd
3555  * operation to an inode.
3556  */
3557 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3558 		u32 requested, u16 cmd)
3559 {
3560 	struct common_audit_data ad;
3561 	struct file_security_struct *fsec = selinux_file(file);
3562 	struct inode *inode = file_inode(file);
3563 	struct inode_security_struct *isec;
3564 	struct lsm_ioctlop_audit ioctl;
3565 	u32 ssid = cred_sid(cred);
3566 	int rc;
3567 	u8 driver = cmd >> 8;
3568 	u8 xperm = cmd & 0xff;
3569 
3570 	ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3571 	ad.u.op = &ioctl;
3572 	ad.u.op->cmd = cmd;
3573 	ad.u.op->path = file->f_path;
3574 
3575 	if (ssid != fsec->sid) {
3576 		rc = avc_has_perm(&selinux_state,
3577 				  ssid, fsec->sid,
3578 				SECCLASS_FD,
3579 				FD__USE,
3580 				&ad);
3581 		if (rc)
3582 			goto out;
3583 	}
3584 
3585 	if (unlikely(IS_PRIVATE(inode)))
3586 		return 0;
3587 
3588 	isec = inode_security(inode);
3589 	rc = avc_has_extended_perms(&selinux_state,
3590 				    ssid, isec->sid, isec->sclass,
3591 				    requested, driver, xperm, &ad);
3592 out:
3593 	return rc;
3594 }
3595 
3596 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3597 			      unsigned long arg)
3598 {
3599 	const struct cred *cred = current_cred();
3600 	int error = 0;
3601 
3602 	switch (cmd) {
3603 	case FIONREAD:
3604 	/* fall through */
3605 	case FIBMAP:
3606 	/* fall through */
3607 	case FIGETBSZ:
3608 	/* fall through */
3609 	case FS_IOC_GETFLAGS:
3610 	/* fall through */
3611 	case FS_IOC_GETVERSION:
3612 		error = file_has_perm(cred, file, FILE__GETATTR);
3613 		break;
3614 
3615 	case FS_IOC_SETFLAGS:
3616 	/* fall through */
3617 	case FS_IOC_SETVERSION:
3618 		error = file_has_perm(cred, file, FILE__SETATTR);
3619 		break;
3620 
3621 	/* sys_ioctl() checks */
3622 	case FIONBIO:
3623 	/* fall through */
3624 	case FIOASYNC:
3625 		error = file_has_perm(cred, file, 0);
3626 		break;
3627 
3628 	case KDSKBENT:
3629 	case KDSKBSENT:
3630 		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3631 					    CAP_OPT_NONE, true);
3632 		break;
3633 
3634 	/* default case assumes that the command will go
3635 	 * to the file's ioctl() function.
3636 	 */
3637 	default:
3638 		error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3639 	}
3640 	return error;
3641 }
3642 
3643 static int default_noexec __ro_after_init;
3644 
3645 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3646 {
3647 	const struct cred *cred = current_cred();
3648 	u32 sid = cred_sid(cred);
3649 	int rc = 0;
3650 
3651 	if (default_noexec &&
3652 	    (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3653 				   (!shared && (prot & PROT_WRITE)))) {
3654 		/*
3655 		 * We are making executable an anonymous mapping or a
3656 		 * private file mapping that will also be writable.
3657 		 * This has an additional check.
3658 		 */
3659 		rc = avc_has_perm(&selinux_state,
3660 				  sid, sid, SECCLASS_PROCESS,
3661 				  PROCESS__EXECMEM, NULL);
3662 		if (rc)
3663 			goto error;
3664 	}
3665 
3666 	if (file) {
3667 		/* read access is always possible with a mapping */
3668 		u32 av = FILE__READ;
3669 
3670 		/* write access only matters if the mapping is shared */
3671 		if (shared && (prot & PROT_WRITE))
3672 			av |= FILE__WRITE;
3673 
3674 		if (prot & PROT_EXEC)
3675 			av |= FILE__EXECUTE;
3676 
3677 		return file_has_perm(cred, file, av);
3678 	}
3679 
3680 error:
3681 	return rc;
3682 }
3683 
3684 static int selinux_mmap_addr(unsigned long addr)
3685 {
3686 	int rc = 0;
3687 
3688 	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3689 		u32 sid = current_sid();
3690 		rc = avc_has_perm(&selinux_state,
3691 				  sid, sid, SECCLASS_MEMPROTECT,
3692 				  MEMPROTECT__MMAP_ZERO, NULL);
3693 	}
3694 
3695 	return rc;
3696 }
3697 
3698 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3699 			     unsigned long prot, unsigned long flags)
3700 {
3701 	struct common_audit_data ad;
3702 	int rc;
3703 
3704 	if (file) {
3705 		ad.type = LSM_AUDIT_DATA_FILE;
3706 		ad.u.file = file;
3707 		rc = inode_has_perm(current_cred(), file_inode(file),
3708 				    FILE__MAP, &ad);
3709 		if (rc)
3710 			return rc;
3711 	}
3712 
3713 	if (selinux_state.checkreqprot)
3714 		prot = reqprot;
3715 
3716 	return file_map_prot_check(file, prot,
3717 				   (flags & MAP_TYPE) == MAP_SHARED);
3718 }
3719 
3720 static int selinux_file_mprotect(struct vm_area_struct *vma,
3721 				 unsigned long reqprot,
3722 				 unsigned long prot)
3723 {
3724 	const struct cred *cred = current_cred();
3725 	u32 sid = cred_sid(cred);
3726 
3727 	if (selinux_state.checkreqprot)
3728 		prot = reqprot;
3729 
3730 	if (default_noexec &&
3731 	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3732 		int rc = 0;
3733 		if (vma->vm_start >= vma->vm_mm->start_brk &&
3734 		    vma->vm_end <= vma->vm_mm->brk) {
3735 			rc = avc_has_perm(&selinux_state,
3736 					  sid, sid, SECCLASS_PROCESS,
3737 					  PROCESS__EXECHEAP, NULL);
3738 		} else if (!vma->vm_file &&
3739 			   ((vma->vm_start <= vma->vm_mm->start_stack &&
3740 			     vma->vm_end >= vma->vm_mm->start_stack) ||
3741 			    vma_is_stack_for_current(vma))) {
3742 			rc = avc_has_perm(&selinux_state,
3743 					  sid, sid, SECCLASS_PROCESS,
3744 					  PROCESS__EXECSTACK, NULL);
3745 		} else if (vma->vm_file && vma->anon_vma) {
3746 			/*
3747 			 * We are making executable a file mapping that has
3748 			 * had some COW done. Since pages might have been
3749 			 * written, check ability to execute the possibly
3750 			 * modified content.  This typically should only
3751 			 * occur for text relocations.
3752 			 */
3753 			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3754 		}
3755 		if (rc)
3756 			return rc;
3757 	}
3758 
3759 	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3760 }
3761 
3762 static int selinux_file_lock(struct file *file, unsigned int cmd)
3763 {
3764 	const struct cred *cred = current_cred();
3765 
3766 	return file_has_perm(cred, file, FILE__LOCK);
3767 }
3768 
3769 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3770 			      unsigned long arg)
3771 {
3772 	const struct cred *cred = current_cred();
3773 	int err = 0;
3774 
3775 	switch (cmd) {
3776 	case F_SETFL:
3777 		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3778 			err = file_has_perm(cred, file, FILE__WRITE);
3779 			break;
3780 		}
3781 		/* fall through */
3782 	case F_SETOWN:
3783 	case F_SETSIG:
3784 	case F_GETFL:
3785 	case F_GETOWN:
3786 	case F_GETSIG:
3787 	case F_GETOWNER_UIDS:
3788 		/* Just check FD__USE permission */
3789 		err = file_has_perm(cred, file, 0);
3790 		break;
3791 	case F_GETLK:
3792 	case F_SETLK:
3793 	case F_SETLKW:
3794 	case F_OFD_GETLK:
3795 	case F_OFD_SETLK:
3796 	case F_OFD_SETLKW:
3797 #if BITS_PER_LONG == 32
3798 	case F_GETLK64:
3799 	case F_SETLK64:
3800 	case F_SETLKW64:
3801 #endif
3802 		err = file_has_perm(cred, file, FILE__LOCK);
3803 		break;
3804 	}
3805 
3806 	return err;
3807 }
3808 
3809 static void selinux_file_set_fowner(struct file *file)
3810 {
3811 	struct file_security_struct *fsec;
3812 
3813 	fsec = selinux_file(file);
3814 	fsec->fown_sid = current_sid();
3815 }
3816 
3817 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3818 				       struct fown_struct *fown, int signum)
3819 {
3820 	struct file *file;
3821 	u32 sid = task_sid(tsk);
3822 	u32 perm;
3823 	struct file_security_struct *fsec;
3824 
3825 	/* struct fown_struct is never outside the context of a struct file */
3826 	file = container_of(fown, struct file, f_owner);
3827 
3828 	fsec = selinux_file(file);
3829 
3830 	if (!signum)
3831 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3832 	else
3833 		perm = signal_to_av(signum);
3834 
3835 	return avc_has_perm(&selinux_state,
3836 			    fsec->fown_sid, sid,
3837 			    SECCLASS_PROCESS, perm, NULL);
3838 }
3839 
3840 static int selinux_file_receive(struct file *file)
3841 {
3842 	const struct cred *cred = current_cred();
3843 
3844 	return file_has_perm(cred, file, file_to_av(file));
3845 }
3846 
3847 static int selinux_file_open(struct file *file)
3848 {
3849 	struct file_security_struct *fsec;
3850 	struct inode_security_struct *isec;
3851 
3852 	fsec = selinux_file(file);
3853 	isec = inode_security(file_inode(file));
3854 	/*
3855 	 * Save inode label and policy sequence number
3856 	 * at open-time so that selinux_file_permission
3857 	 * can determine whether revalidation is necessary.
3858 	 * Task label is already saved in the file security
3859 	 * struct as its SID.
3860 	 */
3861 	fsec->isid = isec->sid;
3862 	fsec->pseqno = avc_policy_seqno(&selinux_state);
3863 	/*
3864 	 * Since the inode label or policy seqno may have changed
3865 	 * between the selinux_inode_permission check and the saving
3866 	 * of state above, recheck that access is still permitted.
3867 	 * Otherwise, access might never be revalidated against the
3868 	 * new inode label or new policy.
3869 	 * This check is not redundant - do not remove.
3870 	 */
3871 	return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3872 }
3873 
3874 /* task security operations */
3875 
3876 static int selinux_task_alloc(struct task_struct *task,
3877 			      unsigned long clone_flags)
3878 {
3879 	u32 sid = current_sid();
3880 
3881 	return avc_has_perm(&selinux_state,
3882 			    sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3883 }
3884 
3885 /*
3886  * prepare a new set of credentials for modification
3887  */
3888 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3889 				gfp_t gfp)
3890 {
3891 	const struct task_security_struct *old_tsec = selinux_cred(old);
3892 	struct task_security_struct *tsec = selinux_cred(new);
3893 
3894 	*tsec = *old_tsec;
3895 	return 0;
3896 }
3897 
3898 /*
3899  * transfer the SELinux data to a blank set of creds
3900  */
3901 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3902 {
3903 	const struct task_security_struct *old_tsec = selinux_cred(old);
3904 	struct task_security_struct *tsec = selinux_cred(new);
3905 
3906 	*tsec = *old_tsec;
3907 }
3908 
3909 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3910 {
3911 	*secid = cred_sid(c);
3912 }
3913 
3914 /*
3915  * set the security data for a kernel service
3916  * - all the creation contexts are set to unlabelled
3917  */
3918 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3919 {
3920 	struct task_security_struct *tsec = selinux_cred(new);
3921 	u32 sid = current_sid();
3922 	int ret;
3923 
3924 	ret = avc_has_perm(&selinux_state,
3925 			   sid, secid,
3926 			   SECCLASS_KERNEL_SERVICE,
3927 			   KERNEL_SERVICE__USE_AS_OVERRIDE,
3928 			   NULL);
3929 	if (ret == 0) {
3930 		tsec->sid = secid;
3931 		tsec->create_sid = 0;
3932 		tsec->keycreate_sid = 0;
3933 		tsec->sockcreate_sid = 0;
3934 	}
3935 	return ret;
3936 }
3937 
3938 /*
3939  * set the file creation context in a security record to the same as the
3940  * objective context of the specified inode
3941  */
3942 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3943 {
3944 	struct inode_security_struct *isec = inode_security(inode);
3945 	struct task_security_struct *tsec = selinux_cred(new);
3946 	u32 sid = current_sid();
3947 	int ret;
3948 
3949 	ret = avc_has_perm(&selinux_state,
3950 			   sid, isec->sid,
3951 			   SECCLASS_KERNEL_SERVICE,
3952 			   KERNEL_SERVICE__CREATE_FILES_AS,
3953 			   NULL);
3954 
3955 	if (ret == 0)
3956 		tsec->create_sid = isec->sid;
3957 	return ret;
3958 }
3959 
3960 static int selinux_kernel_module_request(char *kmod_name)
3961 {
3962 	struct common_audit_data ad;
3963 
3964 	ad.type = LSM_AUDIT_DATA_KMOD;
3965 	ad.u.kmod_name = kmod_name;
3966 
3967 	return avc_has_perm(&selinux_state,
3968 			    current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
3969 			    SYSTEM__MODULE_REQUEST, &ad);
3970 }
3971 
3972 static int selinux_kernel_module_from_file(struct file *file)
3973 {
3974 	struct common_audit_data ad;
3975 	struct inode_security_struct *isec;
3976 	struct file_security_struct *fsec;
3977 	u32 sid = current_sid();
3978 	int rc;
3979 
3980 	/* init_module */
3981 	if (file == NULL)
3982 		return avc_has_perm(&selinux_state,
3983 				    sid, sid, SECCLASS_SYSTEM,
3984 					SYSTEM__MODULE_LOAD, NULL);
3985 
3986 	/* finit_module */
3987 
3988 	ad.type = LSM_AUDIT_DATA_FILE;
3989 	ad.u.file = file;
3990 
3991 	fsec = selinux_file(file);
3992 	if (sid != fsec->sid) {
3993 		rc = avc_has_perm(&selinux_state,
3994 				  sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
3995 		if (rc)
3996 			return rc;
3997 	}
3998 
3999 	isec = inode_security(file_inode(file));
4000 	return avc_has_perm(&selinux_state,
4001 			    sid, isec->sid, SECCLASS_SYSTEM,
4002 				SYSTEM__MODULE_LOAD, &ad);
4003 }
4004 
4005 static int selinux_kernel_read_file(struct file *file,
4006 				    enum kernel_read_file_id id)
4007 {
4008 	int rc = 0;
4009 
4010 	switch (id) {
4011 	case READING_MODULE:
4012 		rc = selinux_kernel_module_from_file(file);
4013 		break;
4014 	default:
4015 		break;
4016 	}
4017 
4018 	return rc;
4019 }
4020 
4021 static int selinux_kernel_load_data(enum kernel_load_data_id id)
4022 {
4023 	int rc = 0;
4024 
4025 	switch (id) {
4026 	case LOADING_MODULE:
4027 		rc = selinux_kernel_module_from_file(NULL);
4028 	default:
4029 		break;
4030 	}
4031 
4032 	return rc;
4033 }
4034 
4035 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4036 {
4037 	return avc_has_perm(&selinux_state,
4038 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4039 			    PROCESS__SETPGID, NULL);
4040 }
4041 
4042 static int selinux_task_getpgid(struct task_struct *p)
4043 {
4044 	return avc_has_perm(&selinux_state,
4045 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4046 			    PROCESS__GETPGID, NULL);
4047 }
4048 
4049 static int selinux_task_getsid(struct task_struct *p)
4050 {
4051 	return avc_has_perm(&selinux_state,
4052 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4053 			    PROCESS__GETSESSION, NULL);
4054 }
4055 
4056 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
4057 {
4058 	*secid = task_sid(p);
4059 }
4060 
4061 static int selinux_task_setnice(struct task_struct *p, int nice)
4062 {
4063 	return avc_has_perm(&selinux_state,
4064 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4065 			    PROCESS__SETSCHED, NULL);
4066 }
4067 
4068 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4069 {
4070 	return avc_has_perm(&selinux_state,
4071 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4072 			    PROCESS__SETSCHED, NULL);
4073 }
4074 
4075 static int selinux_task_getioprio(struct task_struct *p)
4076 {
4077 	return avc_has_perm(&selinux_state,
4078 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4079 			    PROCESS__GETSCHED, NULL);
4080 }
4081 
4082 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4083 				unsigned int flags)
4084 {
4085 	u32 av = 0;
4086 
4087 	if (!flags)
4088 		return 0;
4089 	if (flags & LSM_PRLIMIT_WRITE)
4090 		av |= PROCESS__SETRLIMIT;
4091 	if (flags & LSM_PRLIMIT_READ)
4092 		av |= PROCESS__GETRLIMIT;
4093 	return avc_has_perm(&selinux_state,
4094 			    cred_sid(cred), cred_sid(tcred),
4095 			    SECCLASS_PROCESS, av, NULL);
4096 }
4097 
4098 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4099 		struct rlimit *new_rlim)
4100 {
4101 	struct rlimit *old_rlim = p->signal->rlim + resource;
4102 
4103 	/* Control the ability to change the hard limit (whether
4104 	   lowering or raising it), so that the hard limit can
4105 	   later be used as a safe reset point for the soft limit
4106 	   upon context transitions.  See selinux_bprm_committing_creds. */
4107 	if (old_rlim->rlim_max != new_rlim->rlim_max)
4108 		return avc_has_perm(&selinux_state,
4109 				    current_sid(), task_sid(p),
4110 				    SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4111 
4112 	return 0;
4113 }
4114 
4115 static int selinux_task_setscheduler(struct task_struct *p)
4116 {
4117 	return avc_has_perm(&selinux_state,
4118 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4119 			    PROCESS__SETSCHED, NULL);
4120 }
4121 
4122 static int selinux_task_getscheduler(struct task_struct *p)
4123 {
4124 	return avc_has_perm(&selinux_state,
4125 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4126 			    PROCESS__GETSCHED, NULL);
4127 }
4128 
4129 static int selinux_task_movememory(struct task_struct *p)
4130 {
4131 	return avc_has_perm(&selinux_state,
4132 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4133 			    PROCESS__SETSCHED, NULL);
4134 }
4135 
4136 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4137 				int sig, const struct cred *cred)
4138 {
4139 	u32 secid;
4140 	u32 perm;
4141 
4142 	if (!sig)
4143 		perm = PROCESS__SIGNULL; /* null signal; existence test */
4144 	else
4145 		perm = signal_to_av(sig);
4146 	if (!cred)
4147 		secid = current_sid();
4148 	else
4149 		secid = cred_sid(cred);
4150 	return avc_has_perm(&selinux_state,
4151 			    secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
4152 }
4153 
4154 static void selinux_task_to_inode(struct task_struct *p,
4155 				  struct inode *inode)
4156 {
4157 	struct inode_security_struct *isec = selinux_inode(inode);
4158 	u32 sid = task_sid(p);
4159 
4160 	spin_lock(&isec->lock);
4161 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
4162 	isec->sid = sid;
4163 	isec->initialized = LABEL_INITIALIZED;
4164 	spin_unlock(&isec->lock);
4165 }
4166 
4167 /* Returns error only if unable to parse addresses */
4168 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4169 			struct common_audit_data *ad, u8 *proto)
4170 {
4171 	int offset, ihlen, ret = -EINVAL;
4172 	struct iphdr _iph, *ih;
4173 
4174 	offset = skb_network_offset(skb);
4175 	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4176 	if (ih == NULL)
4177 		goto out;
4178 
4179 	ihlen = ih->ihl * 4;
4180 	if (ihlen < sizeof(_iph))
4181 		goto out;
4182 
4183 	ad->u.net->v4info.saddr = ih->saddr;
4184 	ad->u.net->v4info.daddr = ih->daddr;
4185 	ret = 0;
4186 
4187 	if (proto)
4188 		*proto = ih->protocol;
4189 
4190 	switch (ih->protocol) {
4191 	case IPPROTO_TCP: {
4192 		struct tcphdr _tcph, *th;
4193 
4194 		if (ntohs(ih->frag_off) & IP_OFFSET)
4195 			break;
4196 
4197 		offset += ihlen;
4198 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4199 		if (th == NULL)
4200 			break;
4201 
4202 		ad->u.net->sport = th->source;
4203 		ad->u.net->dport = th->dest;
4204 		break;
4205 	}
4206 
4207 	case IPPROTO_UDP: {
4208 		struct udphdr _udph, *uh;
4209 
4210 		if (ntohs(ih->frag_off) & IP_OFFSET)
4211 			break;
4212 
4213 		offset += ihlen;
4214 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4215 		if (uh == NULL)
4216 			break;
4217 
4218 		ad->u.net->sport = uh->source;
4219 		ad->u.net->dport = uh->dest;
4220 		break;
4221 	}
4222 
4223 	case IPPROTO_DCCP: {
4224 		struct dccp_hdr _dccph, *dh;
4225 
4226 		if (ntohs(ih->frag_off) & IP_OFFSET)
4227 			break;
4228 
4229 		offset += ihlen;
4230 		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4231 		if (dh == NULL)
4232 			break;
4233 
4234 		ad->u.net->sport = dh->dccph_sport;
4235 		ad->u.net->dport = dh->dccph_dport;
4236 		break;
4237 	}
4238 
4239 #if IS_ENABLED(CONFIG_IP_SCTP)
4240 	case IPPROTO_SCTP: {
4241 		struct sctphdr _sctph, *sh;
4242 
4243 		if (ntohs(ih->frag_off) & IP_OFFSET)
4244 			break;
4245 
4246 		offset += ihlen;
4247 		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4248 		if (sh == NULL)
4249 			break;
4250 
4251 		ad->u.net->sport = sh->source;
4252 		ad->u.net->dport = sh->dest;
4253 		break;
4254 	}
4255 #endif
4256 	default:
4257 		break;
4258 	}
4259 out:
4260 	return ret;
4261 }
4262 
4263 #if IS_ENABLED(CONFIG_IPV6)
4264 
4265 /* Returns error only if unable to parse addresses */
4266 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4267 			struct common_audit_data *ad, u8 *proto)
4268 {
4269 	u8 nexthdr;
4270 	int ret = -EINVAL, offset;
4271 	struct ipv6hdr _ipv6h, *ip6;
4272 	__be16 frag_off;
4273 
4274 	offset = skb_network_offset(skb);
4275 	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4276 	if (ip6 == NULL)
4277 		goto out;
4278 
4279 	ad->u.net->v6info.saddr = ip6->saddr;
4280 	ad->u.net->v6info.daddr = ip6->daddr;
4281 	ret = 0;
4282 
4283 	nexthdr = ip6->nexthdr;
4284 	offset += sizeof(_ipv6h);
4285 	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4286 	if (offset < 0)
4287 		goto out;
4288 
4289 	if (proto)
4290 		*proto = nexthdr;
4291 
4292 	switch (nexthdr) {
4293 	case IPPROTO_TCP: {
4294 		struct tcphdr _tcph, *th;
4295 
4296 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4297 		if (th == NULL)
4298 			break;
4299 
4300 		ad->u.net->sport = th->source;
4301 		ad->u.net->dport = th->dest;
4302 		break;
4303 	}
4304 
4305 	case IPPROTO_UDP: {
4306 		struct udphdr _udph, *uh;
4307 
4308 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4309 		if (uh == NULL)
4310 			break;
4311 
4312 		ad->u.net->sport = uh->source;
4313 		ad->u.net->dport = uh->dest;
4314 		break;
4315 	}
4316 
4317 	case IPPROTO_DCCP: {
4318 		struct dccp_hdr _dccph, *dh;
4319 
4320 		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4321 		if (dh == NULL)
4322 			break;
4323 
4324 		ad->u.net->sport = dh->dccph_sport;
4325 		ad->u.net->dport = dh->dccph_dport;
4326 		break;
4327 	}
4328 
4329 #if IS_ENABLED(CONFIG_IP_SCTP)
4330 	case IPPROTO_SCTP: {
4331 		struct sctphdr _sctph, *sh;
4332 
4333 		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4334 		if (sh == NULL)
4335 			break;
4336 
4337 		ad->u.net->sport = sh->source;
4338 		ad->u.net->dport = sh->dest;
4339 		break;
4340 	}
4341 #endif
4342 	/* includes fragments */
4343 	default:
4344 		break;
4345 	}
4346 out:
4347 	return ret;
4348 }
4349 
4350 #endif /* IPV6 */
4351 
4352 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4353 			     char **_addrp, int src, u8 *proto)
4354 {
4355 	char *addrp;
4356 	int ret;
4357 
4358 	switch (ad->u.net->family) {
4359 	case PF_INET:
4360 		ret = selinux_parse_skb_ipv4(skb, ad, proto);
4361 		if (ret)
4362 			goto parse_error;
4363 		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4364 				       &ad->u.net->v4info.daddr);
4365 		goto okay;
4366 
4367 #if IS_ENABLED(CONFIG_IPV6)
4368 	case PF_INET6:
4369 		ret = selinux_parse_skb_ipv6(skb, ad, proto);
4370 		if (ret)
4371 			goto parse_error;
4372 		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4373 				       &ad->u.net->v6info.daddr);
4374 		goto okay;
4375 #endif	/* IPV6 */
4376 	default:
4377 		addrp = NULL;
4378 		goto okay;
4379 	}
4380 
4381 parse_error:
4382 	pr_warn(
4383 	       "SELinux: failure in selinux_parse_skb(),"
4384 	       " unable to parse packet\n");
4385 	return ret;
4386 
4387 okay:
4388 	if (_addrp)
4389 		*_addrp = addrp;
4390 	return 0;
4391 }
4392 
4393 /**
4394  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4395  * @skb: the packet
4396  * @family: protocol family
4397  * @sid: the packet's peer label SID
4398  *
4399  * Description:
4400  * Check the various different forms of network peer labeling and determine
4401  * the peer label/SID for the packet; most of the magic actually occurs in
4402  * the security server function security_net_peersid_cmp().  The function
4403  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4404  * or -EACCES if @sid is invalid due to inconsistencies with the different
4405  * peer labels.
4406  *
4407  */
4408 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4409 {
4410 	int err;
4411 	u32 xfrm_sid;
4412 	u32 nlbl_sid;
4413 	u32 nlbl_type;
4414 
4415 	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4416 	if (unlikely(err))
4417 		return -EACCES;
4418 	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4419 	if (unlikely(err))
4420 		return -EACCES;
4421 
4422 	err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4423 					   nlbl_type, xfrm_sid, sid);
4424 	if (unlikely(err)) {
4425 		pr_warn(
4426 		       "SELinux: failure in selinux_skb_peerlbl_sid(),"
4427 		       " unable to determine packet's peer label\n");
4428 		return -EACCES;
4429 	}
4430 
4431 	return 0;
4432 }
4433 
4434 /**
4435  * selinux_conn_sid - Determine the child socket label for a connection
4436  * @sk_sid: the parent socket's SID
4437  * @skb_sid: the packet's SID
4438  * @conn_sid: the resulting connection SID
4439  *
4440  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4441  * combined with the MLS information from @skb_sid in order to create
4442  * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
4443  * of @sk_sid.  Returns zero on success, negative values on failure.
4444  *
4445  */
4446 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4447 {
4448 	int err = 0;
4449 
4450 	if (skb_sid != SECSID_NULL)
4451 		err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4452 					    conn_sid);
4453 	else
4454 		*conn_sid = sk_sid;
4455 
4456 	return err;
4457 }
4458 
4459 /* socket security operations */
4460 
4461 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4462 				 u16 secclass, u32 *socksid)
4463 {
4464 	if (tsec->sockcreate_sid > SECSID_NULL) {
4465 		*socksid = tsec->sockcreate_sid;
4466 		return 0;
4467 	}
4468 
4469 	return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4470 				       secclass, NULL, socksid);
4471 }
4472 
4473 static int sock_has_perm(struct sock *sk, u32 perms)
4474 {
4475 	struct sk_security_struct *sksec = sk->sk_security;
4476 	struct common_audit_data ad;
4477 	struct lsm_network_audit net = {0,};
4478 
4479 	if (sksec->sid == SECINITSID_KERNEL)
4480 		return 0;
4481 
4482 	ad.type = LSM_AUDIT_DATA_NET;
4483 	ad.u.net = &net;
4484 	ad.u.net->sk = sk;
4485 
4486 	return avc_has_perm(&selinux_state,
4487 			    current_sid(), sksec->sid, sksec->sclass, perms,
4488 			    &ad);
4489 }
4490 
4491 static int selinux_socket_create(int family, int type,
4492 				 int protocol, int kern)
4493 {
4494 	const struct task_security_struct *tsec = selinux_cred(current_cred());
4495 	u32 newsid;
4496 	u16 secclass;
4497 	int rc;
4498 
4499 	if (kern)
4500 		return 0;
4501 
4502 	secclass = socket_type_to_security_class(family, type, protocol);
4503 	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4504 	if (rc)
4505 		return rc;
4506 
4507 	return avc_has_perm(&selinux_state,
4508 			    tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4509 }
4510 
4511 static int selinux_socket_post_create(struct socket *sock, int family,
4512 				      int type, int protocol, int kern)
4513 {
4514 	const struct task_security_struct *tsec = selinux_cred(current_cred());
4515 	struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4516 	struct sk_security_struct *sksec;
4517 	u16 sclass = socket_type_to_security_class(family, type, protocol);
4518 	u32 sid = SECINITSID_KERNEL;
4519 	int err = 0;
4520 
4521 	if (!kern) {
4522 		err = socket_sockcreate_sid(tsec, sclass, &sid);
4523 		if (err)
4524 			return err;
4525 	}
4526 
4527 	isec->sclass = sclass;
4528 	isec->sid = sid;
4529 	isec->initialized = LABEL_INITIALIZED;
4530 
4531 	if (sock->sk) {
4532 		sksec = sock->sk->sk_security;
4533 		sksec->sclass = sclass;
4534 		sksec->sid = sid;
4535 		/* Allows detection of the first association on this socket */
4536 		if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4537 			sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4538 
4539 		err = selinux_netlbl_socket_post_create(sock->sk, family);
4540 	}
4541 
4542 	return err;
4543 }
4544 
4545 static int selinux_socket_socketpair(struct socket *socka,
4546 				     struct socket *sockb)
4547 {
4548 	struct sk_security_struct *sksec_a = socka->sk->sk_security;
4549 	struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4550 
4551 	sksec_a->peer_sid = sksec_b->sid;
4552 	sksec_b->peer_sid = sksec_a->sid;
4553 
4554 	return 0;
4555 }
4556 
4557 /* Range of port numbers used to automatically bind.
4558    Need to determine whether we should perform a name_bind
4559    permission check between the socket and the port number. */
4560 
4561 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4562 {
4563 	struct sock *sk = sock->sk;
4564 	struct sk_security_struct *sksec = sk->sk_security;
4565 	u16 family;
4566 	int err;
4567 
4568 	err = sock_has_perm(sk, SOCKET__BIND);
4569 	if (err)
4570 		goto out;
4571 
4572 	/* If PF_INET or PF_INET6, check name_bind permission for the port. */
4573 	family = sk->sk_family;
4574 	if (family == PF_INET || family == PF_INET6) {
4575 		char *addrp;
4576 		struct common_audit_data ad;
4577 		struct lsm_network_audit net = {0,};
4578 		struct sockaddr_in *addr4 = NULL;
4579 		struct sockaddr_in6 *addr6 = NULL;
4580 		u16 family_sa;
4581 		unsigned short snum;
4582 		u32 sid, node_perm;
4583 
4584 		/*
4585 		 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4586 		 * that validates multiple binding addresses. Because of this
4587 		 * need to check address->sa_family as it is possible to have
4588 		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4589 		 */
4590 		if (addrlen < offsetofend(struct sockaddr, sa_family))
4591 			return -EINVAL;
4592 		family_sa = address->sa_family;
4593 		switch (family_sa) {
4594 		case AF_UNSPEC:
4595 		case AF_INET:
4596 			if (addrlen < sizeof(struct sockaddr_in))
4597 				return -EINVAL;
4598 			addr4 = (struct sockaddr_in *)address;
4599 			if (family_sa == AF_UNSPEC) {
4600 				/* see __inet_bind(), we only want to allow
4601 				 * AF_UNSPEC if the address is INADDR_ANY
4602 				 */
4603 				if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4604 					goto err_af;
4605 				family_sa = AF_INET;
4606 			}
4607 			snum = ntohs(addr4->sin_port);
4608 			addrp = (char *)&addr4->sin_addr.s_addr;
4609 			break;
4610 		case AF_INET6:
4611 			if (addrlen < SIN6_LEN_RFC2133)
4612 				return -EINVAL;
4613 			addr6 = (struct sockaddr_in6 *)address;
4614 			snum = ntohs(addr6->sin6_port);
4615 			addrp = (char *)&addr6->sin6_addr.s6_addr;
4616 			break;
4617 		default:
4618 			goto err_af;
4619 		}
4620 
4621 		ad.type = LSM_AUDIT_DATA_NET;
4622 		ad.u.net = &net;
4623 		ad.u.net->sport = htons(snum);
4624 		ad.u.net->family = family_sa;
4625 
4626 		if (snum) {
4627 			int low, high;
4628 
4629 			inet_get_local_port_range(sock_net(sk), &low, &high);
4630 
4631 			if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4632 			    snum < low || snum > high) {
4633 				err = sel_netport_sid(sk->sk_protocol,
4634 						      snum, &sid);
4635 				if (err)
4636 					goto out;
4637 				err = avc_has_perm(&selinux_state,
4638 						   sksec->sid, sid,
4639 						   sksec->sclass,
4640 						   SOCKET__NAME_BIND, &ad);
4641 				if (err)
4642 					goto out;
4643 			}
4644 		}
4645 
4646 		switch (sksec->sclass) {
4647 		case SECCLASS_TCP_SOCKET:
4648 			node_perm = TCP_SOCKET__NODE_BIND;
4649 			break;
4650 
4651 		case SECCLASS_UDP_SOCKET:
4652 			node_perm = UDP_SOCKET__NODE_BIND;
4653 			break;
4654 
4655 		case SECCLASS_DCCP_SOCKET:
4656 			node_perm = DCCP_SOCKET__NODE_BIND;
4657 			break;
4658 
4659 		case SECCLASS_SCTP_SOCKET:
4660 			node_perm = SCTP_SOCKET__NODE_BIND;
4661 			break;
4662 
4663 		default:
4664 			node_perm = RAWIP_SOCKET__NODE_BIND;
4665 			break;
4666 		}
4667 
4668 		err = sel_netnode_sid(addrp, family_sa, &sid);
4669 		if (err)
4670 			goto out;
4671 
4672 		if (family_sa == AF_INET)
4673 			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4674 		else
4675 			ad.u.net->v6info.saddr = addr6->sin6_addr;
4676 
4677 		err = avc_has_perm(&selinux_state,
4678 				   sksec->sid, sid,
4679 				   sksec->sclass, node_perm, &ad);
4680 		if (err)
4681 			goto out;
4682 	}
4683 out:
4684 	return err;
4685 err_af:
4686 	/* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4687 	if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4688 		return -EINVAL;
4689 	return -EAFNOSUPPORT;
4690 }
4691 
4692 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4693  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4694  */
4695 static int selinux_socket_connect_helper(struct socket *sock,
4696 					 struct sockaddr *address, int addrlen)
4697 {
4698 	struct sock *sk = sock->sk;
4699 	struct sk_security_struct *sksec = sk->sk_security;
4700 	int err;
4701 
4702 	err = sock_has_perm(sk, SOCKET__CONNECT);
4703 	if (err)
4704 		return err;
4705 	if (addrlen < offsetofend(struct sockaddr, sa_family))
4706 		return -EINVAL;
4707 
4708 	/* connect(AF_UNSPEC) has special handling, as it is a documented
4709 	 * way to disconnect the socket
4710 	 */
4711 	if (address->sa_family == AF_UNSPEC)
4712 		return 0;
4713 
4714 	/*
4715 	 * If a TCP, DCCP or SCTP socket, check name_connect permission
4716 	 * for the port.
4717 	 */
4718 	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4719 	    sksec->sclass == SECCLASS_DCCP_SOCKET ||
4720 	    sksec->sclass == SECCLASS_SCTP_SOCKET) {
4721 		struct common_audit_data ad;
4722 		struct lsm_network_audit net = {0,};
4723 		struct sockaddr_in *addr4 = NULL;
4724 		struct sockaddr_in6 *addr6 = NULL;
4725 		unsigned short snum;
4726 		u32 sid, perm;
4727 
4728 		/* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4729 		 * that validates multiple connect addresses. Because of this
4730 		 * need to check address->sa_family as it is possible to have
4731 		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4732 		 */
4733 		switch (address->sa_family) {
4734 		case AF_INET:
4735 			addr4 = (struct sockaddr_in *)address;
4736 			if (addrlen < sizeof(struct sockaddr_in))
4737 				return -EINVAL;
4738 			snum = ntohs(addr4->sin_port);
4739 			break;
4740 		case AF_INET6:
4741 			addr6 = (struct sockaddr_in6 *)address;
4742 			if (addrlen < SIN6_LEN_RFC2133)
4743 				return -EINVAL;
4744 			snum = ntohs(addr6->sin6_port);
4745 			break;
4746 		default:
4747 			/* Note that SCTP services expect -EINVAL, whereas
4748 			 * others expect -EAFNOSUPPORT.
4749 			 */
4750 			if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4751 				return -EINVAL;
4752 			else
4753 				return -EAFNOSUPPORT;
4754 		}
4755 
4756 		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4757 		if (err)
4758 			return err;
4759 
4760 		switch (sksec->sclass) {
4761 		case SECCLASS_TCP_SOCKET:
4762 			perm = TCP_SOCKET__NAME_CONNECT;
4763 			break;
4764 		case SECCLASS_DCCP_SOCKET:
4765 			perm = DCCP_SOCKET__NAME_CONNECT;
4766 			break;
4767 		case SECCLASS_SCTP_SOCKET:
4768 			perm = SCTP_SOCKET__NAME_CONNECT;
4769 			break;
4770 		}
4771 
4772 		ad.type = LSM_AUDIT_DATA_NET;
4773 		ad.u.net = &net;
4774 		ad.u.net->dport = htons(snum);
4775 		ad.u.net->family = address->sa_family;
4776 		err = avc_has_perm(&selinux_state,
4777 				   sksec->sid, sid, sksec->sclass, perm, &ad);
4778 		if (err)
4779 			return err;
4780 	}
4781 
4782 	return 0;
4783 }
4784 
4785 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4786 static int selinux_socket_connect(struct socket *sock,
4787 				  struct sockaddr *address, int addrlen)
4788 {
4789 	int err;
4790 	struct sock *sk = sock->sk;
4791 
4792 	err = selinux_socket_connect_helper(sock, address, addrlen);
4793 	if (err)
4794 		return err;
4795 
4796 	return selinux_netlbl_socket_connect(sk, address);
4797 }
4798 
4799 static int selinux_socket_listen(struct socket *sock, int backlog)
4800 {
4801 	return sock_has_perm(sock->sk, SOCKET__LISTEN);
4802 }
4803 
4804 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4805 {
4806 	int err;
4807 	struct inode_security_struct *isec;
4808 	struct inode_security_struct *newisec;
4809 	u16 sclass;
4810 	u32 sid;
4811 
4812 	err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4813 	if (err)
4814 		return err;
4815 
4816 	isec = inode_security_novalidate(SOCK_INODE(sock));
4817 	spin_lock(&isec->lock);
4818 	sclass = isec->sclass;
4819 	sid = isec->sid;
4820 	spin_unlock(&isec->lock);
4821 
4822 	newisec = inode_security_novalidate(SOCK_INODE(newsock));
4823 	newisec->sclass = sclass;
4824 	newisec->sid = sid;
4825 	newisec->initialized = LABEL_INITIALIZED;
4826 
4827 	return 0;
4828 }
4829 
4830 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4831 				  int size)
4832 {
4833 	return sock_has_perm(sock->sk, SOCKET__WRITE);
4834 }
4835 
4836 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4837 				  int size, int flags)
4838 {
4839 	return sock_has_perm(sock->sk, SOCKET__READ);
4840 }
4841 
4842 static int selinux_socket_getsockname(struct socket *sock)
4843 {
4844 	return sock_has_perm(sock->sk, SOCKET__GETATTR);
4845 }
4846 
4847 static int selinux_socket_getpeername(struct socket *sock)
4848 {
4849 	return sock_has_perm(sock->sk, SOCKET__GETATTR);
4850 }
4851 
4852 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4853 {
4854 	int err;
4855 
4856 	err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4857 	if (err)
4858 		return err;
4859 
4860 	return selinux_netlbl_socket_setsockopt(sock, level, optname);
4861 }
4862 
4863 static int selinux_socket_getsockopt(struct socket *sock, int level,
4864 				     int optname)
4865 {
4866 	return sock_has_perm(sock->sk, SOCKET__GETOPT);
4867 }
4868 
4869 static int selinux_socket_shutdown(struct socket *sock, int how)
4870 {
4871 	return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4872 }
4873 
4874 static int selinux_socket_unix_stream_connect(struct sock *sock,
4875 					      struct sock *other,
4876 					      struct sock *newsk)
4877 {
4878 	struct sk_security_struct *sksec_sock = sock->sk_security;
4879 	struct sk_security_struct *sksec_other = other->sk_security;
4880 	struct sk_security_struct *sksec_new = newsk->sk_security;
4881 	struct common_audit_data ad;
4882 	struct lsm_network_audit net = {0,};
4883 	int err;
4884 
4885 	ad.type = LSM_AUDIT_DATA_NET;
4886 	ad.u.net = &net;
4887 	ad.u.net->sk = other;
4888 
4889 	err = avc_has_perm(&selinux_state,
4890 			   sksec_sock->sid, sksec_other->sid,
4891 			   sksec_other->sclass,
4892 			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4893 	if (err)
4894 		return err;
4895 
4896 	/* server child socket */
4897 	sksec_new->peer_sid = sksec_sock->sid;
4898 	err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
4899 				    sksec_sock->sid, &sksec_new->sid);
4900 	if (err)
4901 		return err;
4902 
4903 	/* connecting socket */
4904 	sksec_sock->peer_sid = sksec_new->sid;
4905 
4906 	return 0;
4907 }
4908 
4909 static int selinux_socket_unix_may_send(struct socket *sock,
4910 					struct socket *other)
4911 {
4912 	struct sk_security_struct *ssec = sock->sk->sk_security;
4913 	struct sk_security_struct *osec = other->sk->sk_security;
4914 	struct common_audit_data ad;
4915 	struct lsm_network_audit net = {0,};
4916 
4917 	ad.type = LSM_AUDIT_DATA_NET;
4918 	ad.u.net = &net;
4919 	ad.u.net->sk = other->sk;
4920 
4921 	return avc_has_perm(&selinux_state,
4922 			    ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4923 			    &ad);
4924 }
4925 
4926 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4927 				    char *addrp, u16 family, u32 peer_sid,
4928 				    struct common_audit_data *ad)
4929 {
4930 	int err;
4931 	u32 if_sid;
4932 	u32 node_sid;
4933 
4934 	err = sel_netif_sid(ns, ifindex, &if_sid);
4935 	if (err)
4936 		return err;
4937 	err = avc_has_perm(&selinux_state,
4938 			   peer_sid, if_sid,
4939 			   SECCLASS_NETIF, NETIF__INGRESS, ad);
4940 	if (err)
4941 		return err;
4942 
4943 	err = sel_netnode_sid(addrp, family, &node_sid);
4944 	if (err)
4945 		return err;
4946 	return avc_has_perm(&selinux_state,
4947 			    peer_sid, node_sid,
4948 			    SECCLASS_NODE, NODE__RECVFROM, ad);
4949 }
4950 
4951 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4952 				       u16 family)
4953 {
4954 	int err = 0;
4955 	struct sk_security_struct *sksec = sk->sk_security;
4956 	u32 sk_sid = sksec->sid;
4957 	struct common_audit_data ad;
4958 	struct lsm_network_audit net = {0,};
4959 	char *addrp;
4960 
4961 	ad.type = LSM_AUDIT_DATA_NET;
4962 	ad.u.net = &net;
4963 	ad.u.net->netif = skb->skb_iif;
4964 	ad.u.net->family = family;
4965 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4966 	if (err)
4967 		return err;
4968 
4969 	if (selinux_secmark_enabled()) {
4970 		err = avc_has_perm(&selinux_state,
4971 				   sk_sid, skb->secmark, SECCLASS_PACKET,
4972 				   PACKET__RECV, &ad);
4973 		if (err)
4974 			return err;
4975 	}
4976 
4977 	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4978 	if (err)
4979 		return err;
4980 	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4981 
4982 	return err;
4983 }
4984 
4985 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4986 {
4987 	int err;
4988 	struct sk_security_struct *sksec = sk->sk_security;
4989 	u16 family = sk->sk_family;
4990 	u32 sk_sid = sksec->sid;
4991 	struct common_audit_data ad;
4992 	struct lsm_network_audit net = {0,};
4993 	char *addrp;
4994 	u8 secmark_active;
4995 	u8 peerlbl_active;
4996 
4997 	if (family != PF_INET && family != PF_INET6)
4998 		return 0;
4999 
5000 	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
5001 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5002 		family = PF_INET;
5003 
5004 	/* If any sort of compatibility mode is enabled then handoff processing
5005 	 * to the selinux_sock_rcv_skb_compat() function to deal with the
5006 	 * special handling.  We do this in an attempt to keep this function
5007 	 * as fast and as clean as possible. */
5008 	if (!selinux_policycap_netpeer())
5009 		return selinux_sock_rcv_skb_compat(sk, skb, family);
5010 
5011 	secmark_active = selinux_secmark_enabled();
5012 	peerlbl_active = selinux_peerlbl_enabled();
5013 	if (!secmark_active && !peerlbl_active)
5014 		return 0;
5015 
5016 	ad.type = LSM_AUDIT_DATA_NET;
5017 	ad.u.net = &net;
5018 	ad.u.net->netif = skb->skb_iif;
5019 	ad.u.net->family = family;
5020 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5021 	if (err)
5022 		return err;
5023 
5024 	if (peerlbl_active) {
5025 		u32 peer_sid;
5026 
5027 		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5028 		if (err)
5029 			return err;
5030 		err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5031 					       addrp, family, peer_sid, &ad);
5032 		if (err) {
5033 			selinux_netlbl_err(skb, family, err, 0);
5034 			return err;
5035 		}
5036 		err = avc_has_perm(&selinux_state,
5037 				   sk_sid, peer_sid, SECCLASS_PEER,
5038 				   PEER__RECV, &ad);
5039 		if (err) {
5040 			selinux_netlbl_err(skb, family, err, 0);
5041 			return err;
5042 		}
5043 	}
5044 
5045 	if (secmark_active) {
5046 		err = avc_has_perm(&selinux_state,
5047 				   sk_sid, skb->secmark, SECCLASS_PACKET,
5048 				   PACKET__RECV, &ad);
5049 		if (err)
5050 			return err;
5051 	}
5052 
5053 	return err;
5054 }
5055 
5056 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
5057 					    int __user *optlen, unsigned len)
5058 {
5059 	int err = 0;
5060 	char *scontext;
5061 	u32 scontext_len;
5062 	struct sk_security_struct *sksec = sock->sk->sk_security;
5063 	u32 peer_sid = SECSID_NULL;
5064 
5065 	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5066 	    sksec->sclass == SECCLASS_TCP_SOCKET ||
5067 	    sksec->sclass == SECCLASS_SCTP_SOCKET)
5068 		peer_sid = sksec->peer_sid;
5069 	if (peer_sid == SECSID_NULL)
5070 		return -ENOPROTOOPT;
5071 
5072 	err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5073 				      &scontext_len);
5074 	if (err)
5075 		return err;
5076 
5077 	if (scontext_len > len) {
5078 		err = -ERANGE;
5079 		goto out_len;
5080 	}
5081 
5082 	if (copy_to_user(optval, scontext, scontext_len))
5083 		err = -EFAULT;
5084 
5085 out_len:
5086 	if (put_user(scontext_len, optlen))
5087 		err = -EFAULT;
5088 	kfree(scontext);
5089 	return err;
5090 }
5091 
5092 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5093 {
5094 	u32 peer_secid = SECSID_NULL;
5095 	u16 family;
5096 	struct inode_security_struct *isec;
5097 
5098 	if (skb && skb->protocol == htons(ETH_P_IP))
5099 		family = PF_INET;
5100 	else if (skb && skb->protocol == htons(ETH_P_IPV6))
5101 		family = PF_INET6;
5102 	else if (sock)
5103 		family = sock->sk->sk_family;
5104 	else
5105 		goto out;
5106 
5107 	if (sock && family == PF_UNIX) {
5108 		isec = inode_security_novalidate(SOCK_INODE(sock));
5109 		peer_secid = isec->sid;
5110 	} else if (skb)
5111 		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5112 
5113 out:
5114 	*secid = peer_secid;
5115 	if (peer_secid == SECSID_NULL)
5116 		return -EINVAL;
5117 	return 0;
5118 }
5119 
5120 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5121 {
5122 	struct sk_security_struct *sksec;
5123 
5124 	sksec = kzalloc(sizeof(*sksec), priority);
5125 	if (!sksec)
5126 		return -ENOMEM;
5127 
5128 	sksec->peer_sid = SECINITSID_UNLABELED;
5129 	sksec->sid = SECINITSID_UNLABELED;
5130 	sksec->sclass = SECCLASS_SOCKET;
5131 	selinux_netlbl_sk_security_reset(sksec);
5132 	sk->sk_security = sksec;
5133 
5134 	return 0;
5135 }
5136 
5137 static void selinux_sk_free_security(struct sock *sk)
5138 {
5139 	struct sk_security_struct *sksec = sk->sk_security;
5140 
5141 	sk->sk_security = NULL;
5142 	selinux_netlbl_sk_security_free(sksec);
5143 	kfree(sksec);
5144 }
5145 
5146 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5147 {
5148 	struct sk_security_struct *sksec = sk->sk_security;
5149 	struct sk_security_struct *newsksec = newsk->sk_security;
5150 
5151 	newsksec->sid = sksec->sid;
5152 	newsksec->peer_sid = sksec->peer_sid;
5153 	newsksec->sclass = sksec->sclass;
5154 
5155 	selinux_netlbl_sk_security_reset(newsksec);
5156 }
5157 
5158 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5159 {
5160 	if (!sk)
5161 		*secid = SECINITSID_ANY_SOCKET;
5162 	else {
5163 		struct sk_security_struct *sksec = sk->sk_security;
5164 
5165 		*secid = sksec->sid;
5166 	}
5167 }
5168 
5169 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5170 {
5171 	struct inode_security_struct *isec =
5172 		inode_security_novalidate(SOCK_INODE(parent));
5173 	struct sk_security_struct *sksec = sk->sk_security;
5174 
5175 	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5176 	    sk->sk_family == PF_UNIX)
5177 		isec->sid = sksec->sid;
5178 	sksec->sclass = isec->sclass;
5179 }
5180 
5181 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5182  * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5183  * already present).
5184  */
5185 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5186 				      struct sk_buff *skb)
5187 {
5188 	struct sk_security_struct *sksec = ep->base.sk->sk_security;
5189 	struct common_audit_data ad;
5190 	struct lsm_network_audit net = {0,};
5191 	u8 peerlbl_active;
5192 	u32 peer_sid = SECINITSID_UNLABELED;
5193 	u32 conn_sid;
5194 	int err = 0;
5195 
5196 	if (!selinux_policycap_extsockclass())
5197 		return 0;
5198 
5199 	peerlbl_active = selinux_peerlbl_enabled();
5200 
5201 	if (peerlbl_active) {
5202 		/* This will return peer_sid = SECSID_NULL if there are
5203 		 * no peer labels, see security_net_peersid_resolve().
5204 		 */
5205 		err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5206 					      &peer_sid);
5207 		if (err)
5208 			return err;
5209 
5210 		if (peer_sid == SECSID_NULL)
5211 			peer_sid = SECINITSID_UNLABELED;
5212 	}
5213 
5214 	if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5215 		sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5216 
5217 		/* Here as first association on socket. As the peer SID
5218 		 * was allowed by peer recv (and the netif/node checks),
5219 		 * then it is approved by policy and used as the primary
5220 		 * peer SID for getpeercon(3).
5221 		 */
5222 		sksec->peer_sid = peer_sid;
5223 	} else if  (sksec->peer_sid != peer_sid) {
5224 		/* Other association peer SIDs are checked to enforce
5225 		 * consistency among the peer SIDs.
5226 		 */
5227 		ad.type = LSM_AUDIT_DATA_NET;
5228 		ad.u.net = &net;
5229 		ad.u.net->sk = ep->base.sk;
5230 		err = avc_has_perm(&selinux_state,
5231 				   sksec->peer_sid, peer_sid, sksec->sclass,
5232 				   SCTP_SOCKET__ASSOCIATION, &ad);
5233 		if (err)
5234 			return err;
5235 	}
5236 
5237 	/* Compute the MLS component for the connection and store
5238 	 * the information in ep. This will be used by SCTP TCP type
5239 	 * sockets and peeled off connections as they cause a new
5240 	 * socket to be generated. selinux_sctp_sk_clone() will then
5241 	 * plug this into the new socket.
5242 	 */
5243 	err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5244 	if (err)
5245 		return err;
5246 
5247 	ep->secid = conn_sid;
5248 	ep->peer_secid = peer_sid;
5249 
5250 	/* Set any NetLabel labels including CIPSO/CALIPSO options. */
5251 	return selinux_netlbl_sctp_assoc_request(ep, skb);
5252 }
5253 
5254 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5255  * based on their @optname.
5256  */
5257 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5258 				     struct sockaddr *address,
5259 				     int addrlen)
5260 {
5261 	int len, err = 0, walk_size = 0;
5262 	void *addr_buf;
5263 	struct sockaddr *addr;
5264 	struct socket *sock;
5265 
5266 	if (!selinux_policycap_extsockclass())
5267 		return 0;
5268 
5269 	/* Process one or more addresses that may be IPv4 or IPv6 */
5270 	sock = sk->sk_socket;
5271 	addr_buf = address;
5272 
5273 	while (walk_size < addrlen) {
5274 		if (walk_size + sizeof(sa_family_t) > addrlen)
5275 			return -EINVAL;
5276 
5277 		addr = addr_buf;
5278 		switch (addr->sa_family) {
5279 		case AF_UNSPEC:
5280 		case AF_INET:
5281 			len = sizeof(struct sockaddr_in);
5282 			break;
5283 		case AF_INET6:
5284 			len = sizeof(struct sockaddr_in6);
5285 			break;
5286 		default:
5287 			return -EINVAL;
5288 		}
5289 
5290 		if (walk_size + len > addrlen)
5291 			return -EINVAL;
5292 
5293 		err = -EINVAL;
5294 		switch (optname) {
5295 		/* Bind checks */
5296 		case SCTP_PRIMARY_ADDR:
5297 		case SCTP_SET_PEER_PRIMARY_ADDR:
5298 		case SCTP_SOCKOPT_BINDX_ADD:
5299 			err = selinux_socket_bind(sock, addr, len);
5300 			break;
5301 		/* Connect checks */
5302 		case SCTP_SOCKOPT_CONNECTX:
5303 		case SCTP_PARAM_SET_PRIMARY:
5304 		case SCTP_PARAM_ADD_IP:
5305 		case SCTP_SENDMSG_CONNECT:
5306 			err = selinux_socket_connect_helper(sock, addr, len);
5307 			if (err)
5308 				return err;
5309 
5310 			/* As selinux_sctp_bind_connect() is called by the
5311 			 * SCTP protocol layer, the socket is already locked,
5312 			 * therefore selinux_netlbl_socket_connect_locked() is
5313 			 * is called here. The situations handled are:
5314 			 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5315 			 * whenever a new IP address is added or when a new
5316 			 * primary address is selected.
5317 			 * Note that an SCTP connect(2) call happens before
5318 			 * the SCTP protocol layer and is handled via
5319 			 * selinux_socket_connect().
5320 			 */
5321 			err = selinux_netlbl_socket_connect_locked(sk, addr);
5322 			break;
5323 		}
5324 
5325 		if (err)
5326 			return err;
5327 
5328 		addr_buf += len;
5329 		walk_size += len;
5330 	}
5331 
5332 	return 0;
5333 }
5334 
5335 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5336 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5337 				  struct sock *newsk)
5338 {
5339 	struct sk_security_struct *sksec = sk->sk_security;
5340 	struct sk_security_struct *newsksec = newsk->sk_security;
5341 
5342 	/* If policy does not support SECCLASS_SCTP_SOCKET then call
5343 	 * the non-sctp clone version.
5344 	 */
5345 	if (!selinux_policycap_extsockclass())
5346 		return selinux_sk_clone_security(sk, newsk);
5347 
5348 	newsksec->sid = ep->secid;
5349 	newsksec->peer_sid = ep->peer_secid;
5350 	newsksec->sclass = sksec->sclass;
5351 	selinux_netlbl_sctp_sk_clone(sk, newsk);
5352 }
5353 
5354 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
5355 				     struct request_sock *req)
5356 {
5357 	struct sk_security_struct *sksec = sk->sk_security;
5358 	int err;
5359 	u16 family = req->rsk_ops->family;
5360 	u32 connsid;
5361 	u32 peersid;
5362 
5363 	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5364 	if (err)
5365 		return err;
5366 	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5367 	if (err)
5368 		return err;
5369 	req->secid = connsid;
5370 	req->peer_secid = peersid;
5371 
5372 	return selinux_netlbl_inet_conn_request(req, family);
5373 }
5374 
5375 static void selinux_inet_csk_clone(struct sock *newsk,
5376 				   const struct request_sock *req)
5377 {
5378 	struct sk_security_struct *newsksec = newsk->sk_security;
5379 
5380 	newsksec->sid = req->secid;
5381 	newsksec->peer_sid = req->peer_secid;
5382 	/* NOTE: Ideally, we should also get the isec->sid for the
5383 	   new socket in sync, but we don't have the isec available yet.
5384 	   So we will wait until sock_graft to do it, by which
5385 	   time it will have been created and available. */
5386 
5387 	/* We don't need to take any sort of lock here as we are the only
5388 	 * thread with access to newsksec */
5389 	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5390 }
5391 
5392 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5393 {
5394 	u16 family = sk->sk_family;
5395 	struct sk_security_struct *sksec = sk->sk_security;
5396 
5397 	/* handle mapped IPv4 packets arriving via IPv6 sockets */
5398 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5399 		family = PF_INET;
5400 
5401 	selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5402 }
5403 
5404 static int selinux_secmark_relabel_packet(u32 sid)
5405 {
5406 	const struct task_security_struct *__tsec;
5407 	u32 tsid;
5408 
5409 	__tsec = selinux_cred(current_cred());
5410 	tsid = __tsec->sid;
5411 
5412 	return avc_has_perm(&selinux_state,
5413 			    tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5414 			    NULL);
5415 }
5416 
5417 static void selinux_secmark_refcount_inc(void)
5418 {
5419 	atomic_inc(&selinux_secmark_refcount);
5420 }
5421 
5422 static void selinux_secmark_refcount_dec(void)
5423 {
5424 	atomic_dec(&selinux_secmark_refcount);
5425 }
5426 
5427 static void selinux_req_classify_flow(const struct request_sock *req,
5428 				      struct flowi *fl)
5429 {
5430 	fl->flowi_secid = req->secid;
5431 }
5432 
5433 static int selinux_tun_dev_alloc_security(void **security)
5434 {
5435 	struct tun_security_struct *tunsec;
5436 
5437 	tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5438 	if (!tunsec)
5439 		return -ENOMEM;
5440 	tunsec->sid = current_sid();
5441 
5442 	*security = tunsec;
5443 	return 0;
5444 }
5445 
5446 static void selinux_tun_dev_free_security(void *security)
5447 {
5448 	kfree(security);
5449 }
5450 
5451 static int selinux_tun_dev_create(void)
5452 {
5453 	u32 sid = current_sid();
5454 
5455 	/* we aren't taking into account the "sockcreate" SID since the socket
5456 	 * that is being created here is not a socket in the traditional sense,
5457 	 * instead it is a private sock, accessible only to the kernel, and
5458 	 * representing a wide range of network traffic spanning multiple
5459 	 * connections unlike traditional sockets - check the TUN driver to
5460 	 * get a better understanding of why this socket is special */
5461 
5462 	return avc_has_perm(&selinux_state,
5463 			    sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5464 			    NULL);
5465 }
5466 
5467 static int selinux_tun_dev_attach_queue(void *security)
5468 {
5469 	struct tun_security_struct *tunsec = security;
5470 
5471 	return avc_has_perm(&selinux_state,
5472 			    current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5473 			    TUN_SOCKET__ATTACH_QUEUE, NULL);
5474 }
5475 
5476 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5477 {
5478 	struct tun_security_struct *tunsec = security;
5479 	struct sk_security_struct *sksec = sk->sk_security;
5480 
5481 	/* we don't currently perform any NetLabel based labeling here and it
5482 	 * isn't clear that we would want to do so anyway; while we could apply
5483 	 * labeling without the support of the TUN user the resulting labeled
5484 	 * traffic from the other end of the connection would almost certainly
5485 	 * cause confusion to the TUN user that had no idea network labeling
5486 	 * protocols were being used */
5487 
5488 	sksec->sid = tunsec->sid;
5489 	sksec->sclass = SECCLASS_TUN_SOCKET;
5490 
5491 	return 0;
5492 }
5493 
5494 static int selinux_tun_dev_open(void *security)
5495 {
5496 	struct tun_security_struct *tunsec = security;
5497 	u32 sid = current_sid();
5498 	int err;
5499 
5500 	err = avc_has_perm(&selinux_state,
5501 			   sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5502 			   TUN_SOCKET__RELABELFROM, NULL);
5503 	if (err)
5504 		return err;
5505 	err = avc_has_perm(&selinux_state,
5506 			   sid, sid, SECCLASS_TUN_SOCKET,
5507 			   TUN_SOCKET__RELABELTO, NULL);
5508 	if (err)
5509 		return err;
5510 	tunsec->sid = sid;
5511 
5512 	return 0;
5513 }
5514 
5515 #ifdef CONFIG_NETFILTER
5516 
5517 static unsigned int selinux_ip_forward(struct sk_buff *skb,
5518 				       const struct net_device *indev,
5519 				       u16 family)
5520 {
5521 	int err;
5522 	char *addrp;
5523 	u32 peer_sid;
5524 	struct common_audit_data ad;
5525 	struct lsm_network_audit net = {0,};
5526 	u8 secmark_active;
5527 	u8 netlbl_active;
5528 	u8 peerlbl_active;
5529 
5530 	if (!selinux_policycap_netpeer())
5531 		return NF_ACCEPT;
5532 
5533 	secmark_active = selinux_secmark_enabled();
5534 	netlbl_active = netlbl_enabled();
5535 	peerlbl_active = selinux_peerlbl_enabled();
5536 	if (!secmark_active && !peerlbl_active)
5537 		return NF_ACCEPT;
5538 
5539 	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5540 		return NF_DROP;
5541 
5542 	ad.type = LSM_AUDIT_DATA_NET;
5543 	ad.u.net = &net;
5544 	ad.u.net->netif = indev->ifindex;
5545 	ad.u.net->family = family;
5546 	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5547 		return NF_DROP;
5548 
5549 	if (peerlbl_active) {
5550 		err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5551 					       addrp, family, peer_sid, &ad);
5552 		if (err) {
5553 			selinux_netlbl_err(skb, family, err, 1);
5554 			return NF_DROP;
5555 		}
5556 	}
5557 
5558 	if (secmark_active)
5559 		if (avc_has_perm(&selinux_state,
5560 				 peer_sid, skb->secmark,
5561 				 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5562 			return NF_DROP;
5563 
5564 	if (netlbl_active)
5565 		/* we do this in the FORWARD path and not the POST_ROUTING
5566 		 * path because we want to make sure we apply the necessary
5567 		 * labeling before IPsec is applied so we can leverage AH
5568 		 * protection */
5569 		if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5570 			return NF_DROP;
5571 
5572 	return NF_ACCEPT;
5573 }
5574 
5575 static unsigned int selinux_ipv4_forward(void *priv,
5576 					 struct sk_buff *skb,
5577 					 const struct nf_hook_state *state)
5578 {
5579 	return selinux_ip_forward(skb, state->in, PF_INET);
5580 }
5581 
5582 #if IS_ENABLED(CONFIG_IPV6)
5583 static unsigned int selinux_ipv6_forward(void *priv,
5584 					 struct sk_buff *skb,
5585 					 const struct nf_hook_state *state)
5586 {
5587 	return selinux_ip_forward(skb, state->in, PF_INET6);
5588 }
5589 #endif	/* IPV6 */
5590 
5591 static unsigned int selinux_ip_output(struct sk_buff *skb,
5592 				      u16 family)
5593 {
5594 	struct sock *sk;
5595 	u32 sid;
5596 
5597 	if (!netlbl_enabled())
5598 		return NF_ACCEPT;
5599 
5600 	/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5601 	 * because we want to make sure we apply the necessary labeling
5602 	 * before IPsec is applied so we can leverage AH protection */
5603 	sk = skb->sk;
5604 	if (sk) {
5605 		struct sk_security_struct *sksec;
5606 
5607 		if (sk_listener(sk))
5608 			/* if the socket is the listening state then this
5609 			 * packet is a SYN-ACK packet which means it needs to
5610 			 * be labeled based on the connection/request_sock and
5611 			 * not the parent socket.  unfortunately, we can't
5612 			 * lookup the request_sock yet as it isn't queued on
5613 			 * the parent socket until after the SYN-ACK is sent.
5614 			 * the "solution" is to simply pass the packet as-is
5615 			 * as any IP option based labeling should be copied
5616 			 * from the initial connection request (in the IP
5617 			 * layer).  it is far from ideal, but until we get a
5618 			 * security label in the packet itself this is the
5619 			 * best we can do. */
5620 			return NF_ACCEPT;
5621 
5622 		/* standard practice, label using the parent socket */
5623 		sksec = sk->sk_security;
5624 		sid = sksec->sid;
5625 	} else
5626 		sid = SECINITSID_KERNEL;
5627 	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5628 		return NF_DROP;
5629 
5630 	return NF_ACCEPT;
5631 }
5632 
5633 static unsigned int selinux_ipv4_output(void *priv,
5634 					struct sk_buff *skb,
5635 					const struct nf_hook_state *state)
5636 {
5637 	return selinux_ip_output(skb, PF_INET);
5638 }
5639 
5640 #if IS_ENABLED(CONFIG_IPV6)
5641 static unsigned int selinux_ipv6_output(void *priv,
5642 					struct sk_buff *skb,
5643 					const struct nf_hook_state *state)
5644 {
5645 	return selinux_ip_output(skb, PF_INET6);
5646 }
5647 #endif	/* IPV6 */
5648 
5649 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5650 						int ifindex,
5651 						u16 family)
5652 {
5653 	struct sock *sk = skb_to_full_sk(skb);
5654 	struct sk_security_struct *sksec;
5655 	struct common_audit_data ad;
5656 	struct lsm_network_audit net = {0,};
5657 	char *addrp;
5658 	u8 proto;
5659 
5660 	if (sk == NULL)
5661 		return NF_ACCEPT;
5662 	sksec = sk->sk_security;
5663 
5664 	ad.type = LSM_AUDIT_DATA_NET;
5665 	ad.u.net = &net;
5666 	ad.u.net->netif = ifindex;
5667 	ad.u.net->family = family;
5668 	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5669 		return NF_DROP;
5670 
5671 	if (selinux_secmark_enabled())
5672 		if (avc_has_perm(&selinux_state,
5673 				 sksec->sid, skb->secmark,
5674 				 SECCLASS_PACKET, PACKET__SEND, &ad))
5675 			return NF_DROP_ERR(-ECONNREFUSED);
5676 
5677 	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5678 		return NF_DROP_ERR(-ECONNREFUSED);
5679 
5680 	return NF_ACCEPT;
5681 }
5682 
5683 static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5684 					 const struct net_device *outdev,
5685 					 u16 family)
5686 {
5687 	u32 secmark_perm;
5688 	u32 peer_sid;
5689 	int ifindex = outdev->ifindex;
5690 	struct sock *sk;
5691 	struct common_audit_data ad;
5692 	struct lsm_network_audit net = {0,};
5693 	char *addrp;
5694 	u8 secmark_active;
5695 	u8 peerlbl_active;
5696 
5697 	/* If any sort of compatibility mode is enabled then handoff processing
5698 	 * to the selinux_ip_postroute_compat() function to deal with the
5699 	 * special handling.  We do this in an attempt to keep this function
5700 	 * as fast and as clean as possible. */
5701 	if (!selinux_policycap_netpeer())
5702 		return selinux_ip_postroute_compat(skb, ifindex, family);
5703 
5704 	secmark_active = selinux_secmark_enabled();
5705 	peerlbl_active = selinux_peerlbl_enabled();
5706 	if (!secmark_active && !peerlbl_active)
5707 		return NF_ACCEPT;
5708 
5709 	sk = skb_to_full_sk(skb);
5710 
5711 #ifdef CONFIG_XFRM
5712 	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5713 	 * packet transformation so allow the packet to pass without any checks
5714 	 * since we'll have another chance to perform access control checks
5715 	 * when the packet is on it's final way out.
5716 	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5717 	 *       is NULL, in this case go ahead and apply access control.
5718 	 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5719 	 *       TCP listening state we cannot wait until the XFRM processing
5720 	 *       is done as we will miss out on the SA label if we do;
5721 	 *       unfortunately, this means more work, but it is only once per
5722 	 *       connection. */
5723 	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5724 	    !(sk && sk_listener(sk)))
5725 		return NF_ACCEPT;
5726 #endif
5727 
5728 	if (sk == NULL) {
5729 		/* Without an associated socket the packet is either coming
5730 		 * from the kernel or it is being forwarded; check the packet
5731 		 * to determine which and if the packet is being forwarded
5732 		 * query the packet directly to determine the security label. */
5733 		if (skb->skb_iif) {
5734 			secmark_perm = PACKET__FORWARD_OUT;
5735 			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5736 				return NF_DROP;
5737 		} else {
5738 			secmark_perm = PACKET__SEND;
5739 			peer_sid = SECINITSID_KERNEL;
5740 		}
5741 	} else if (sk_listener(sk)) {
5742 		/* Locally generated packet but the associated socket is in the
5743 		 * listening state which means this is a SYN-ACK packet.  In
5744 		 * this particular case the correct security label is assigned
5745 		 * to the connection/request_sock but unfortunately we can't
5746 		 * query the request_sock as it isn't queued on the parent
5747 		 * socket until after the SYN-ACK packet is sent; the only
5748 		 * viable choice is to regenerate the label like we do in
5749 		 * selinux_inet_conn_request().  See also selinux_ip_output()
5750 		 * for similar problems. */
5751 		u32 skb_sid;
5752 		struct sk_security_struct *sksec;
5753 
5754 		sksec = sk->sk_security;
5755 		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5756 			return NF_DROP;
5757 		/* At this point, if the returned skb peerlbl is SECSID_NULL
5758 		 * and the packet has been through at least one XFRM
5759 		 * transformation then we must be dealing with the "final"
5760 		 * form of labeled IPsec packet; since we've already applied
5761 		 * all of our access controls on this packet we can safely
5762 		 * pass the packet. */
5763 		if (skb_sid == SECSID_NULL) {
5764 			switch (family) {
5765 			case PF_INET:
5766 				if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5767 					return NF_ACCEPT;
5768 				break;
5769 			case PF_INET6:
5770 				if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5771 					return NF_ACCEPT;
5772 				break;
5773 			default:
5774 				return NF_DROP_ERR(-ECONNREFUSED);
5775 			}
5776 		}
5777 		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5778 			return NF_DROP;
5779 		secmark_perm = PACKET__SEND;
5780 	} else {
5781 		/* Locally generated packet, fetch the security label from the
5782 		 * associated socket. */
5783 		struct sk_security_struct *sksec = sk->sk_security;
5784 		peer_sid = sksec->sid;
5785 		secmark_perm = PACKET__SEND;
5786 	}
5787 
5788 	ad.type = LSM_AUDIT_DATA_NET;
5789 	ad.u.net = &net;
5790 	ad.u.net->netif = ifindex;
5791 	ad.u.net->family = family;
5792 	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5793 		return NF_DROP;
5794 
5795 	if (secmark_active)
5796 		if (avc_has_perm(&selinux_state,
5797 				 peer_sid, skb->secmark,
5798 				 SECCLASS_PACKET, secmark_perm, &ad))
5799 			return NF_DROP_ERR(-ECONNREFUSED);
5800 
5801 	if (peerlbl_active) {
5802 		u32 if_sid;
5803 		u32 node_sid;
5804 
5805 		if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5806 			return NF_DROP;
5807 		if (avc_has_perm(&selinux_state,
5808 				 peer_sid, if_sid,
5809 				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5810 			return NF_DROP_ERR(-ECONNREFUSED);
5811 
5812 		if (sel_netnode_sid(addrp, family, &node_sid))
5813 			return NF_DROP;
5814 		if (avc_has_perm(&selinux_state,
5815 				 peer_sid, node_sid,
5816 				 SECCLASS_NODE, NODE__SENDTO, &ad))
5817 			return NF_DROP_ERR(-ECONNREFUSED);
5818 	}
5819 
5820 	return NF_ACCEPT;
5821 }
5822 
5823 static unsigned int selinux_ipv4_postroute(void *priv,
5824 					   struct sk_buff *skb,
5825 					   const struct nf_hook_state *state)
5826 {
5827 	return selinux_ip_postroute(skb, state->out, PF_INET);
5828 }
5829 
5830 #if IS_ENABLED(CONFIG_IPV6)
5831 static unsigned int selinux_ipv6_postroute(void *priv,
5832 					   struct sk_buff *skb,
5833 					   const struct nf_hook_state *state)
5834 {
5835 	return selinux_ip_postroute(skb, state->out, PF_INET6);
5836 }
5837 #endif	/* IPV6 */
5838 
5839 #endif	/* CONFIG_NETFILTER */
5840 
5841 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5842 {
5843 	int rc = 0;
5844 	unsigned int msg_len;
5845 	unsigned int data_len = skb->len;
5846 	unsigned char *data = skb->data;
5847 	struct nlmsghdr *nlh;
5848 	struct sk_security_struct *sksec = sk->sk_security;
5849 	u16 sclass = sksec->sclass;
5850 	u32 perm;
5851 
5852 	while (data_len >= nlmsg_total_size(0)) {
5853 		nlh = (struct nlmsghdr *)data;
5854 
5855 		/* NOTE: the nlmsg_len field isn't reliably set by some netlink
5856 		 *       users which means we can't reject skb's with bogus
5857 		 *       length fields; our solution is to follow what
5858 		 *       netlink_rcv_skb() does and simply skip processing at
5859 		 *       messages with length fields that are clearly junk
5860 		 */
5861 		if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5862 			return 0;
5863 
5864 		rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5865 		if (rc == 0) {
5866 			rc = sock_has_perm(sk, perm);
5867 			if (rc)
5868 				return rc;
5869 		} else if (rc == -EINVAL) {
5870 			/* -EINVAL is a missing msg/perm mapping */
5871 			pr_warn_ratelimited("SELinux: unrecognized netlink"
5872 				" message: protocol=%hu nlmsg_type=%hu sclass=%s"
5873 				" pid=%d comm=%s\n",
5874 				sk->sk_protocol, nlh->nlmsg_type,
5875 				secclass_map[sclass - 1].name,
5876 				task_pid_nr(current), current->comm);
5877 			if (enforcing_enabled(&selinux_state) &&
5878 			    !security_get_allow_unknown(&selinux_state))
5879 				return rc;
5880 			rc = 0;
5881 		} else if (rc == -ENOENT) {
5882 			/* -ENOENT is a missing socket/class mapping, ignore */
5883 			rc = 0;
5884 		} else {
5885 			return rc;
5886 		}
5887 
5888 		/* move to the next message after applying netlink padding */
5889 		msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
5890 		if (msg_len >= data_len)
5891 			return 0;
5892 		data_len -= msg_len;
5893 		data += msg_len;
5894 	}
5895 
5896 	return rc;
5897 }
5898 
5899 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5900 {
5901 	isec->sclass = sclass;
5902 	isec->sid = current_sid();
5903 }
5904 
5905 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5906 			u32 perms)
5907 {
5908 	struct ipc_security_struct *isec;
5909 	struct common_audit_data ad;
5910 	u32 sid = current_sid();
5911 
5912 	isec = selinux_ipc(ipc_perms);
5913 
5914 	ad.type = LSM_AUDIT_DATA_IPC;
5915 	ad.u.ipc_id = ipc_perms->key;
5916 
5917 	return avc_has_perm(&selinux_state,
5918 			    sid, isec->sid, isec->sclass, perms, &ad);
5919 }
5920 
5921 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5922 {
5923 	struct msg_security_struct *msec;
5924 
5925 	msec = selinux_msg_msg(msg);
5926 	msec->sid = SECINITSID_UNLABELED;
5927 
5928 	return 0;
5929 }
5930 
5931 /* message queue security operations */
5932 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5933 {
5934 	struct ipc_security_struct *isec;
5935 	struct common_audit_data ad;
5936 	u32 sid = current_sid();
5937 	int rc;
5938 
5939 	isec = selinux_ipc(msq);
5940 	ipc_init_security(isec, SECCLASS_MSGQ);
5941 
5942 	ad.type = LSM_AUDIT_DATA_IPC;
5943 	ad.u.ipc_id = msq->key;
5944 
5945 	rc = avc_has_perm(&selinux_state,
5946 			  sid, isec->sid, SECCLASS_MSGQ,
5947 			  MSGQ__CREATE, &ad);
5948 	return rc;
5949 }
5950 
5951 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
5952 {
5953 	struct ipc_security_struct *isec;
5954 	struct common_audit_data ad;
5955 	u32 sid = current_sid();
5956 
5957 	isec = selinux_ipc(msq);
5958 
5959 	ad.type = LSM_AUDIT_DATA_IPC;
5960 	ad.u.ipc_id = msq->key;
5961 
5962 	return avc_has_perm(&selinux_state,
5963 			    sid, isec->sid, SECCLASS_MSGQ,
5964 			    MSGQ__ASSOCIATE, &ad);
5965 }
5966 
5967 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
5968 {
5969 	int err;
5970 	int perms;
5971 
5972 	switch (cmd) {
5973 	case IPC_INFO:
5974 	case MSG_INFO:
5975 		/* No specific object, just general system-wide information. */
5976 		return avc_has_perm(&selinux_state,
5977 				    current_sid(), SECINITSID_KERNEL,
5978 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
5979 	case IPC_STAT:
5980 	case MSG_STAT:
5981 	case MSG_STAT_ANY:
5982 		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5983 		break;
5984 	case IPC_SET:
5985 		perms = MSGQ__SETATTR;
5986 		break;
5987 	case IPC_RMID:
5988 		perms = MSGQ__DESTROY;
5989 		break;
5990 	default:
5991 		return 0;
5992 	}
5993 
5994 	err = ipc_has_perm(msq, perms);
5995 	return err;
5996 }
5997 
5998 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
5999 {
6000 	struct ipc_security_struct *isec;
6001 	struct msg_security_struct *msec;
6002 	struct common_audit_data ad;
6003 	u32 sid = current_sid();
6004 	int rc;
6005 
6006 	isec = selinux_ipc(msq);
6007 	msec = selinux_msg_msg(msg);
6008 
6009 	/*
6010 	 * First time through, need to assign label to the message
6011 	 */
6012 	if (msec->sid == SECINITSID_UNLABELED) {
6013 		/*
6014 		 * Compute new sid based on current process and
6015 		 * message queue this message will be stored in
6016 		 */
6017 		rc = security_transition_sid(&selinux_state, sid, isec->sid,
6018 					     SECCLASS_MSG, NULL, &msec->sid);
6019 		if (rc)
6020 			return rc;
6021 	}
6022 
6023 	ad.type = LSM_AUDIT_DATA_IPC;
6024 	ad.u.ipc_id = msq->key;
6025 
6026 	/* Can this process write to the queue? */
6027 	rc = avc_has_perm(&selinux_state,
6028 			  sid, isec->sid, SECCLASS_MSGQ,
6029 			  MSGQ__WRITE, &ad);
6030 	if (!rc)
6031 		/* Can this process send the message */
6032 		rc = avc_has_perm(&selinux_state,
6033 				  sid, msec->sid, SECCLASS_MSG,
6034 				  MSG__SEND, &ad);
6035 	if (!rc)
6036 		/* Can the message be put in the queue? */
6037 		rc = avc_has_perm(&selinux_state,
6038 				  msec->sid, isec->sid, SECCLASS_MSGQ,
6039 				  MSGQ__ENQUEUE, &ad);
6040 
6041 	return rc;
6042 }
6043 
6044 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6045 				    struct task_struct *target,
6046 				    long type, int mode)
6047 {
6048 	struct ipc_security_struct *isec;
6049 	struct msg_security_struct *msec;
6050 	struct common_audit_data ad;
6051 	u32 sid = task_sid(target);
6052 	int rc;
6053 
6054 	isec = selinux_ipc(msq);
6055 	msec = selinux_msg_msg(msg);
6056 
6057 	ad.type = LSM_AUDIT_DATA_IPC;
6058 	ad.u.ipc_id = msq->key;
6059 
6060 	rc = avc_has_perm(&selinux_state,
6061 			  sid, isec->sid,
6062 			  SECCLASS_MSGQ, MSGQ__READ, &ad);
6063 	if (!rc)
6064 		rc = avc_has_perm(&selinux_state,
6065 				  sid, msec->sid,
6066 				  SECCLASS_MSG, MSG__RECEIVE, &ad);
6067 	return rc;
6068 }
6069 
6070 /* Shared Memory security operations */
6071 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6072 {
6073 	struct ipc_security_struct *isec;
6074 	struct common_audit_data ad;
6075 	u32 sid = current_sid();
6076 	int rc;
6077 
6078 	isec = selinux_ipc(shp);
6079 	ipc_init_security(isec, SECCLASS_SHM);
6080 
6081 	ad.type = LSM_AUDIT_DATA_IPC;
6082 	ad.u.ipc_id = shp->key;
6083 
6084 	rc = avc_has_perm(&selinux_state,
6085 			  sid, isec->sid, SECCLASS_SHM,
6086 			  SHM__CREATE, &ad);
6087 	return rc;
6088 }
6089 
6090 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6091 {
6092 	struct ipc_security_struct *isec;
6093 	struct common_audit_data ad;
6094 	u32 sid = current_sid();
6095 
6096 	isec = selinux_ipc(shp);
6097 
6098 	ad.type = LSM_AUDIT_DATA_IPC;
6099 	ad.u.ipc_id = shp->key;
6100 
6101 	return avc_has_perm(&selinux_state,
6102 			    sid, isec->sid, SECCLASS_SHM,
6103 			    SHM__ASSOCIATE, &ad);
6104 }
6105 
6106 /* Note, at this point, shp is locked down */
6107 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6108 {
6109 	int perms;
6110 	int err;
6111 
6112 	switch (cmd) {
6113 	case IPC_INFO:
6114 	case SHM_INFO:
6115 		/* No specific object, just general system-wide information. */
6116 		return avc_has_perm(&selinux_state,
6117 				    current_sid(), SECINITSID_KERNEL,
6118 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6119 	case IPC_STAT:
6120 	case SHM_STAT:
6121 	case SHM_STAT_ANY:
6122 		perms = SHM__GETATTR | SHM__ASSOCIATE;
6123 		break;
6124 	case IPC_SET:
6125 		perms = SHM__SETATTR;
6126 		break;
6127 	case SHM_LOCK:
6128 	case SHM_UNLOCK:
6129 		perms = SHM__LOCK;
6130 		break;
6131 	case IPC_RMID:
6132 		perms = SHM__DESTROY;
6133 		break;
6134 	default:
6135 		return 0;
6136 	}
6137 
6138 	err = ipc_has_perm(shp, perms);
6139 	return err;
6140 }
6141 
6142 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6143 			     char __user *shmaddr, int shmflg)
6144 {
6145 	u32 perms;
6146 
6147 	if (shmflg & SHM_RDONLY)
6148 		perms = SHM__READ;
6149 	else
6150 		perms = SHM__READ | SHM__WRITE;
6151 
6152 	return ipc_has_perm(shp, perms);
6153 }
6154 
6155 /* Semaphore security operations */
6156 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6157 {
6158 	struct ipc_security_struct *isec;
6159 	struct common_audit_data ad;
6160 	u32 sid = current_sid();
6161 	int rc;
6162 
6163 	isec = selinux_ipc(sma);
6164 	ipc_init_security(isec, SECCLASS_SEM);
6165 
6166 	ad.type = LSM_AUDIT_DATA_IPC;
6167 	ad.u.ipc_id = sma->key;
6168 
6169 	rc = avc_has_perm(&selinux_state,
6170 			  sid, isec->sid, SECCLASS_SEM,
6171 			  SEM__CREATE, &ad);
6172 	return rc;
6173 }
6174 
6175 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6176 {
6177 	struct ipc_security_struct *isec;
6178 	struct common_audit_data ad;
6179 	u32 sid = current_sid();
6180 
6181 	isec = selinux_ipc(sma);
6182 
6183 	ad.type = LSM_AUDIT_DATA_IPC;
6184 	ad.u.ipc_id = sma->key;
6185 
6186 	return avc_has_perm(&selinux_state,
6187 			    sid, isec->sid, SECCLASS_SEM,
6188 			    SEM__ASSOCIATE, &ad);
6189 }
6190 
6191 /* Note, at this point, sma is locked down */
6192 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6193 {
6194 	int err;
6195 	u32 perms;
6196 
6197 	switch (cmd) {
6198 	case IPC_INFO:
6199 	case SEM_INFO:
6200 		/* No specific object, just general system-wide information. */
6201 		return avc_has_perm(&selinux_state,
6202 				    current_sid(), SECINITSID_KERNEL,
6203 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6204 	case GETPID:
6205 	case GETNCNT:
6206 	case GETZCNT:
6207 		perms = SEM__GETATTR;
6208 		break;
6209 	case GETVAL:
6210 	case GETALL:
6211 		perms = SEM__READ;
6212 		break;
6213 	case SETVAL:
6214 	case SETALL:
6215 		perms = SEM__WRITE;
6216 		break;
6217 	case IPC_RMID:
6218 		perms = SEM__DESTROY;
6219 		break;
6220 	case IPC_SET:
6221 		perms = SEM__SETATTR;
6222 		break;
6223 	case IPC_STAT:
6224 	case SEM_STAT:
6225 	case SEM_STAT_ANY:
6226 		perms = SEM__GETATTR | SEM__ASSOCIATE;
6227 		break;
6228 	default:
6229 		return 0;
6230 	}
6231 
6232 	err = ipc_has_perm(sma, perms);
6233 	return err;
6234 }
6235 
6236 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6237 			     struct sembuf *sops, unsigned nsops, int alter)
6238 {
6239 	u32 perms;
6240 
6241 	if (alter)
6242 		perms = SEM__READ | SEM__WRITE;
6243 	else
6244 		perms = SEM__READ;
6245 
6246 	return ipc_has_perm(sma, perms);
6247 }
6248 
6249 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6250 {
6251 	u32 av = 0;
6252 
6253 	av = 0;
6254 	if (flag & S_IRUGO)
6255 		av |= IPC__UNIX_READ;
6256 	if (flag & S_IWUGO)
6257 		av |= IPC__UNIX_WRITE;
6258 
6259 	if (av == 0)
6260 		return 0;
6261 
6262 	return ipc_has_perm(ipcp, av);
6263 }
6264 
6265 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6266 {
6267 	struct ipc_security_struct *isec = selinux_ipc(ipcp);
6268 	*secid = isec->sid;
6269 }
6270 
6271 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6272 {
6273 	if (inode)
6274 		inode_doinit_with_dentry(inode, dentry);
6275 }
6276 
6277 static int selinux_getprocattr(struct task_struct *p,
6278 			       char *name, char **value)
6279 {
6280 	const struct task_security_struct *__tsec;
6281 	u32 sid;
6282 	int error;
6283 	unsigned len;
6284 
6285 	rcu_read_lock();
6286 	__tsec = selinux_cred(__task_cred(p));
6287 
6288 	if (current != p) {
6289 		error = avc_has_perm(&selinux_state,
6290 				     current_sid(), __tsec->sid,
6291 				     SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6292 		if (error)
6293 			goto bad;
6294 	}
6295 
6296 	if (!strcmp(name, "current"))
6297 		sid = __tsec->sid;
6298 	else if (!strcmp(name, "prev"))
6299 		sid = __tsec->osid;
6300 	else if (!strcmp(name, "exec"))
6301 		sid = __tsec->exec_sid;
6302 	else if (!strcmp(name, "fscreate"))
6303 		sid = __tsec->create_sid;
6304 	else if (!strcmp(name, "keycreate"))
6305 		sid = __tsec->keycreate_sid;
6306 	else if (!strcmp(name, "sockcreate"))
6307 		sid = __tsec->sockcreate_sid;
6308 	else {
6309 		error = -EINVAL;
6310 		goto bad;
6311 	}
6312 	rcu_read_unlock();
6313 
6314 	if (!sid)
6315 		return 0;
6316 
6317 	error = security_sid_to_context(&selinux_state, sid, value, &len);
6318 	if (error)
6319 		return error;
6320 	return len;
6321 
6322 bad:
6323 	rcu_read_unlock();
6324 	return error;
6325 }
6326 
6327 static int selinux_setprocattr(const char *name, void *value, size_t size)
6328 {
6329 	struct task_security_struct *tsec;
6330 	struct cred *new;
6331 	u32 mysid = current_sid(), sid = 0, ptsid;
6332 	int error;
6333 	char *str = value;
6334 
6335 	/*
6336 	 * Basic control over ability to set these attributes at all.
6337 	 */
6338 	if (!strcmp(name, "exec"))
6339 		error = avc_has_perm(&selinux_state,
6340 				     mysid, mysid, SECCLASS_PROCESS,
6341 				     PROCESS__SETEXEC, NULL);
6342 	else if (!strcmp(name, "fscreate"))
6343 		error = avc_has_perm(&selinux_state,
6344 				     mysid, mysid, SECCLASS_PROCESS,
6345 				     PROCESS__SETFSCREATE, NULL);
6346 	else if (!strcmp(name, "keycreate"))
6347 		error = avc_has_perm(&selinux_state,
6348 				     mysid, mysid, SECCLASS_PROCESS,
6349 				     PROCESS__SETKEYCREATE, NULL);
6350 	else if (!strcmp(name, "sockcreate"))
6351 		error = avc_has_perm(&selinux_state,
6352 				     mysid, mysid, SECCLASS_PROCESS,
6353 				     PROCESS__SETSOCKCREATE, NULL);
6354 	else if (!strcmp(name, "current"))
6355 		error = avc_has_perm(&selinux_state,
6356 				     mysid, mysid, SECCLASS_PROCESS,
6357 				     PROCESS__SETCURRENT, NULL);
6358 	else
6359 		error = -EINVAL;
6360 	if (error)
6361 		return error;
6362 
6363 	/* Obtain a SID for the context, if one was specified. */
6364 	if (size && str[0] && str[0] != '\n') {
6365 		if (str[size-1] == '\n') {
6366 			str[size-1] = 0;
6367 			size--;
6368 		}
6369 		error = security_context_to_sid(&selinux_state, value, size,
6370 						&sid, GFP_KERNEL);
6371 		if (error == -EINVAL && !strcmp(name, "fscreate")) {
6372 			if (!has_cap_mac_admin(true)) {
6373 				struct audit_buffer *ab;
6374 				size_t audit_size;
6375 
6376 				/* We strip a nul only if it is at the end, otherwise the
6377 				 * context contains a nul and we should audit that */
6378 				if (str[size - 1] == '\0')
6379 					audit_size = size - 1;
6380 				else
6381 					audit_size = size;
6382 				ab = audit_log_start(audit_context(),
6383 						     GFP_ATOMIC,
6384 						     AUDIT_SELINUX_ERR);
6385 				audit_log_format(ab, "op=fscreate invalid_context=");
6386 				audit_log_n_untrustedstring(ab, value, audit_size);
6387 				audit_log_end(ab);
6388 
6389 				return error;
6390 			}
6391 			error = security_context_to_sid_force(
6392 						      &selinux_state,
6393 						      value, size, &sid);
6394 		}
6395 		if (error)
6396 			return error;
6397 	}
6398 
6399 	new = prepare_creds();
6400 	if (!new)
6401 		return -ENOMEM;
6402 
6403 	/* Permission checking based on the specified context is
6404 	   performed during the actual operation (execve,
6405 	   open/mkdir/...), when we know the full context of the
6406 	   operation.  See selinux_bprm_creds_for_exec for the execve
6407 	   checks and may_create for the file creation checks. The
6408 	   operation will then fail if the context is not permitted. */
6409 	tsec = selinux_cred(new);
6410 	if (!strcmp(name, "exec")) {
6411 		tsec->exec_sid = sid;
6412 	} else if (!strcmp(name, "fscreate")) {
6413 		tsec->create_sid = sid;
6414 	} else if (!strcmp(name, "keycreate")) {
6415 		if (sid) {
6416 			error = avc_has_perm(&selinux_state, mysid, sid,
6417 					     SECCLASS_KEY, KEY__CREATE, NULL);
6418 			if (error)
6419 				goto abort_change;
6420 		}
6421 		tsec->keycreate_sid = sid;
6422 	} else if (!strcmp(name, "sockcreate")) {
6423 		tsec->sockcreate_sid = sid;
6424 	} else if (!strcmp(name, "current")) {
6425 		error = -EINVAL;
6426 		if (sid == 0)
6427 			goto abort_change;
6428 
6429 		/* Only allow single threaded processes to change context */
6430 		error = -EPERM;
6431 		if (!current_is_single_threaded()) {
6432 			error = security_bounded_transition(&selinux_state,
6433 							    tsec->sid, sid);
6434 			if (error)
6435 				goto abort_change;
6436 		}
6437 
6438 		/* Check permissions for the transition. */
6439 		error = avc_has_perm(&selinux_state,
6440 				     tsec->sid, sid, SECCLASS_PROCESS,
6441 				     PROCESS__DYNTRANSITION, NULL);
6442 		if (error)
6443 			goto abort_change;
6444 
6445 		/* Check for ptracing, and update the task SID if ok.
6446 		   Otherwise, leave SID unchanged and fail. */
6447 		ptsid = ptrace_parent_sid();
6448 		if (ptsid != 0) {
6449 			error = avc_has_perm(&selinux_state,
6450 					     ptsid, sid, SECCLASS_PROCESS,
6451 					     PROCESS__PTRACE, NULL);
6452 			if (error)
6453 				goto abort_change;
6454 		}
6455 
6456 		tsec->sid = sid;
6457 	} else {
6458 		error = -EINVAL;
6459 		goto abort_change;
6460 	}
6461 
6462 	commit_creds(new);
6463 	return size;
6464 
6465 abort_change:
6466 	abort_creds(new);
6467 	return error;
6468 }
6469 
6470 static int selinux_ismaclabel(const char *name)
6471 {
6472 	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6473 }
6474 
6475 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6476 {
6477 	return security_sid_to_context(&selinux_state, secid,
6478 				       secdata, seclen);
6479 }
6480 
6481 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6482 {
6483 	return security_context_to_sid(&selinux_state, secdata, seclen,
6484 				       secid, GFP_KERNEL);
6485 }
6486 
6487 static void selinux_release_secctx(char *secdata, u32 seclen)
6488 {
6489 	kfree(secdata);
6490 }
6491 
6492 static void selinux_inode_invalidate_secctx(struct inode *inode)
6493 {
6494 	struct inode_security_struct *isec = selinux_inode(inode);
6495 
6496 	spin_lock(&isec->lock);
6497 	isec->initialized = LABEL_INVALID;
6498 	spin_unlock(&isec->lock);
6499 }
6500 
6501 /*
6502  *	called with inode->i_mutex locked
6503  */
6504 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6505 {
6506 	int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6507 					   ctx, ctxlen, 0);
6508 	/* Do not return error when suppressing label (SBLABEL_MNT not set). */
6509 	return rc == -EOPNOTSUPP ? 0 : rc;
6510 }
6511 
6512 /*
6513  *	called with inode->i_mutex locked
6514  */
6515 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6516 {
6517 	return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6518 }
6519 
6520 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6521 {
6522 	int len = 0;
6523 	len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6524 						ctx, true);
6525 	if (len < 0)
6526 		return len;
6527 	*ctxlen = len;
6528 	return 0;
6529 }
6530 #ifdef CONFIG_KEYS
6531 
6532 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6533 			     unsigned long flags)
6534 {
6535 	const struct task_security_struct *tsec;
6536 	struct key_security_struct *ksec;
6537 
6538 	ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6539 	if (!ksec)
6540 		return -ENOMEM;
6541 
6542 	tsec = selinux_cred(cred);
6543 	if (tsec->keycreate_sid)
6544 		ksec->sid = tsec->keycreate_sid;
6545 	else
6546 		ksec->sid = tsec->sid;
6547 
6548 	k->security = ksec;
6549 	return 0;
6550 }
6551 
6552 static void selinux_key_free(struct key *k)
6553 {
6554 	struct key_security_struct *ksec = k->security;
6555 
6556 	k->security = NULL;
6557 	kfree(ksec);
6558 }
6559 
6560 static int selinux_key_permission(key_ref_t key_ref,
6561 				  const struct cred *cred,
6562 				  enum key_need_perm need_perm)
6563 {
6564 	struct key *key;
6565 	struct key_security_struct *ksec;
6566 	u32 perm, sid;
6567 
6568 	switch (need_perm) {
6569 	case KEY_NEED_VIEW:
6570 		perm = KEY__VIEW;
6571 		break;
6572 	case KEY_NEED_READ:
6573 		perm = KEY__READ;
6574 		break;
6575 	case KEY_NEED_WRITE:
6576 		perm = KEY__WRITE;
6577 		break;
6578 	case KEY_NEED_SEARCH:
6579 		perm = KEY__SEARCH;
6580 		break;
6581 	case KEY_NEED_LINK:
6582 		perm = KEY__LINK;
6583 		break;
6584 	case KEY_NEED_SETATTR:
6585 		perm = KEY__SETATTR;
6586 		break;
6587 	case KEY_NEED_UNLINK:
6588 	case KEY_SYSADMIN_OVERRIDE:
6589 	case KEY_AUTHTOKEN_OVERRIDE:
6590 	case KEY_DEFER_PERM_CHECK:
6591 		return 0;
6592 	default:
6593 		WARN_ON(1);
6594 		return -EPERM;
6595 
6596 	}
6597 
6598 	sid = cred_sid(cred);
6599 	key = key_ref_to_ptr(key_ref);
6600 	ksec = key->security;
6601 
6602 	return avc_has_perm(&selinux_state,
6603 			    sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6604 }
6605 
6606 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6607 {
6608 	struct key_security_struct *ksec = key->security;
6609 	char *context = NULL;
6610 	unsigned len;
6611 	int rc;
6612 
6613 	rc = security_sid_to_context(&selinux_state, ksec->sid,
6614 				     &context, &len);
6615 	if (!rc)
6616 		rc = len;
6617 	*_buffer = context;
6618 	return rc;
6619 }
6620 
6621 #ifdef CONFIG_KEY_NOTIFICATIONS
6622 static int selinux_watch_key(struct key *key)
6623 {
6624 	struct key_security_struct *ksec = key->security;
6625 	u32 sid = current_sid();
6626 
6627 	return avc_has_perm(&selinux_state,
6628 			    sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6629 }
6630 #endif
6631 #endif
6632 
6633 #ifdef CONFIG_SECURITY_INFINIBAND
6634 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6635 {
6636 	struct common_audit_data ad;
6637 	int err;
6638 	u32 sid = 0;
6639 	struct ib_security_struct *sec = ib_sec;
6640 	struct lsm_ibpkey_audit ibpkey;
6641 
6642 	err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6643 	if (err)
6644 		return err;
6645 
6646 	ad.type = LSM_AUDIT_DATA_IBPKEY;
6647 	ibpkey.subnet_prefix = subnet_prefix;
6648 	ibpkey.pkey = pkey_val;
6649 	ad.u.ibpkey = &ibpkey;
6650 	return avc_has_perm(&selinux_state,
6651 			    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(&selinux_state, dev_name, port_num,
6666 				      &sid);
6667 
6668 	if (err)
6669 		return err;
6670 
6671 	ad.type = LSM_AUDIT_DATA_IBENDPORT;
6672 	strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
6673 	ibendport.port = port_num;
6674 	ad.u.ibendport = &ibendport;
6675 	return avc_has_perm(&selinux_state,
6676 			    sec->sid, sid,
6677 			    SECCLASS_INFINIBAND_ENDPORT,
6678 			    INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6679 }
6680 
6681 static int selinux_ib_alloc_security(void **ib_sec)
6682 {
6683 	struct ib_security_struct *sec;
6684 
6685 	sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6686 	if (!sec)
6687 		return -ENOMEM;
6688 	sec->sid = current_sid();
6689 
6690 	*ib_sec = sec;
6691 	return 0;
6692 }
6693 
6694 static void selinux_ib_free_security(void *ib_sec)
6695 {
6696 	kfree(ib_sec);
6697 }
6698 #endif
6699 
6700 #ifdef CONFIG_BPF_SYSCALL
6701 static int selinux_bpf(int cmd, union bpf_attr *attr,
6702 				     unsigned int size)
6703 {
6704 	u32 sid = current_sid();
6705 	int ret;
6706 
6707 	switch (cmd) {
6708 	case BPF_MAP_CREATE:
6709 		ret = avc_has_perm(&selinux_state,
6710 				   sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6711 				   NULL);
6712 		break;
6713 	case BPF_PROG_LOAD:
6714 		ret = avc_has_perm(&selinux_state,
6715 				   sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6716 				   NULL);
6717 		break;
6718 	default:
6719 		ret = 0;
6720 		break;
6721 	}
6722 
6723 	return ret;
6724 }
6725 
6726 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6727 {
6728 	u32 av = 0;
6729 
6730 	if (fmode & FMODE_READ)
6731 		av |= BPF__MAP_READ;
6732 	if (fmode & FMODE_WRITE)
6733 		av |= BPF__MAP_WRITE;
6734 	return av;
6735 }
6736 
6737 /* This function will check the file pass through unix socket or binder to see
6738  * if it is a bpf related object. And apply correspinding checks on the bpf
6739  * object based on the type. The bpf maps and programs, not like other files and
6740  * socket, are using a shared anonymous inode inside the kernel as their inode.
6741  * So checking that inode cannot identify if the process have privilege to
6742  * access the bpf object and that's why we have to add this additional check in
6743  * selinux_file_receive and selinux_binder_transfer_files.
6744  */
6745 static int bpf_fd_pass(struct file *file, u32 sid)
6746 {
6747 	struct bpf_security_struct *bpfsec;
6748 	struct bpf_prog *prog;
6749 	struct bpf_map *map;
6750 	int ret;
6751 
6752 	if (file->f_op == &bpf_map_fops) {
6753 		map = file->private_data;
6754 		bpfsec = map->security;
6755 		ret = avc_has_perm(&selinux_state,
6756 				   sid, bpfsec->sid, SECCLASS_BPF,
6757 				   bpf_map_fmode_to_av(file->f_mode), NULL);
6758 		if (ret)
6759 			return ret;
6760 	} else if (file->f_op == &bpf_prog_fops) {
6761 		prog = file->private_data;
6762 		bpfsec = prog->aux->security;
6763 		ret = avc_has_perm(&selinux_state,
6764 				   sid, bpfsec->sid, SECCLASS_BPF,
6765 				   BPF__PROG_RUN, NULL);
6766 		if (ret)
6767 			return ret;
6768 	}
6769 	return 0;
6770 }
6771 
6772 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6773 {
6774 	u32 sid = current_sid();
6775 	struct bpf_security_struct *bpfsec;
6776 
6777 	bpfsec = map->security;
6778 	return avc_has_perm(&selinux_state,
6779 			    sid, bpfsec->sid, SECCLASS_BPF,
6780 			    bpf_map_fmode_to_av(fmode), NULL);
6781 }
6782 
6783 static int selinux_bpf_prog(struct bpf_prog *prog)
6784 {
6785 	u32 sid = current_sid();
6786 	struct bpf_security_struct *bpfsec;
6787 
6788 	bpfsec = prog->aux->security;
6789 	return avc_has_perm(&selinux_state,
6790 			    sid, bpfsec->sid, SECCLASS_BPF,
6791 			    BPF__PROG_RUN, NULL);
6792 }
6793 
6794 static int selinux_bpf_map_alloc(struct bpf_map *map)
6795 {
6796 	struct bpf_security_struct *bpfsec;
6797 
6798 	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6799 	if (!bpfsec)
6800 		return -ENOMEM;
6801 
6802 	bpfsec->sid = current_sid();
6803 	map->security = bpfsec;
6804 
6805 	return 0;
6806 }
6807 
6808 static void selinux_bpf_map_free(struct bpf_map *map)
6809 {
6810 	struct bpf_security_struct *bpfsec = map->security;
6811 
6812 	map->security = NULL;
6813 	kfree(bpfsec);
6814 }
6815 
6816 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6817 {
6818 	struct bpf_security_struct *bpfsec;
6819 
6820 	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6821 	if (!bpfsec)
6822 		return -ENOMEM;
6823 
6824 	bpfsec->sid = current_sid();
6825 	aux->security = bpfsec;
6826 
6827 	return 0;
6828 }
6829 
6830 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6831 {
6832 	struct bpf_security_struct *bpfsec = aux->security;
6833 
6834 	aux->security = NULL;
6835 	kfree(bpfsec);
6836 }
6837 #endif
6838 
6839 static int selinux_lockdown(enum lockdown_reason what)
6840 {
6841 	struct common_audit_data ad;
6842 	u32 sid = current_sid();
6843 	int invalid_reason = (what <= LOCKDOWN_NONE) ||
6844 			     (what == LOCKDOWN_INTEGRITY_MAX) ||
6845 			     (what >= LOCKDOWN_CONFIDENTIALITY_MAX);
6846 
6847 	if (WARN(invalid_reason, "Invalid lockdown reason")) {
6848 		audit_log(audit_context(),
6849 			  GFP_ATOMIC, AUDIT_SELINUX_ERR,
6850 			  "lockdown_reason=invalid");
6851 		return -EINVAL;
6852 	}
6853 
6854 	ad.type = LSM_AUDIT_DATA_LOCKDOWN;
6855 	ad.u.reason = what;
6856 
6857 	if (what <= LOCKDOWN_INTEGRITY_MAX)
6858 		return avc_has_perm(&selinux_state,
6859 				    sid, sid, SECCLASS_LOCKDOWN,
6860 				    LOCKDOWN__INTEGRITY, &ad);
6861 	else
6862 		return avc_has_perm(&selinux_state,
6863 				    sid, sid, SECCLASS_LOCKDOWN,
6864 				    LOCKDOWN__CONFIDENTIALITY, &ad);
6865 }
6866 
6867 struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
6868 	.lbs_cred = sizeof(struct task_security_struct),
6869 	.lbs_file = sizeof(struct file_security_struct),
6870 	.lbs_inode = sizeof(struct inode_security_struct),
6871 	.lbs_ipc = sizeof(struct ipc_security_struct),
6872 	.lbs_msg_msg = sizeof(struct msg_security_struct),
6873 };
6874 
6875 #ifdef CONFIG_PERF_EVENTS
6876 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
6877 {
6878 	u32 requested, sid = current_sid();
6879 
6880 	if (type == PERF_SECURITY_OPEN)
6881 		requested = PERF_EVENT__OPEN;
6882 	else if (type == PERF_SECURITY_CPU)
6883 		requested = PERF_EVENT__CPU;
6884 	else if (type == PERF_SECURITY_KERNEL)
6885 		requested = PERF_EVENT__KERNEL;
6886 	else if (type == PERF_SECURITY_TRACEPOINT)
6887 		requested = PERF_EVENT__TRACEPOINT;
6888 	else
6889 		return -EINVAL;
6890 
6891 	return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT,
6892 			    requested, NULL);
6893 }
6894 
6895 static int selinux_perf_event_alloc(struct perf_event *event)
6896 {
6897 	struct perf_event_security_struct *perfsec;
6898 
6899 	perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
6900 	if (!perfsec)
6901 		return -ENOMEM;
6902 
6903 	perfsec->sid = current_sid();
6904 	event->security = perfsec;
6905 
6906 	return 0;
6907 }
6908 
6909 static void selinux_perf_event_free(struct perf_event *event)
6910 {
6911 	struct perf_event_security_struct *perfsec = event->security;
6912 
6913 	event->security = NULL;
6914 	kfree(perfsec);
6915 }
6916 
6917 static int selinux_perf_event_read(struct perf_event *event)
6918 {
6919 	struct perf_event_security_struct *perfsec = event->security;
6920 	u32 sid = current_sid();
6921 
6922 	return avc_has_perm(&selinux_state, sid, perfsec->sid,
6923 			    SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
6924 }
6925 
6926 static int selinux_perf_event_write(struct perf_event *event)
6927 {
6928 	struct perf_event_security_struct *perfsec = event->security;
6929 	u32 sid = current_sid();
6930 
6931 	return avc_has_perm(&selinux_state, sid, perfsec->sid,
6932 			    SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
6933 }
6934 #endif
6935 
6936 /*
6937  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
6938  * 1. any hooks that don't belong to (2.) or (3.) below,
6939  * 2. hooks that both access structures allocated by other hooks, and allocate
6940  *    structures that can be later accessed by other hooks (mostly "cloning"
6941  *    hooks),
6942  * 3. hooks that only allocate structures that can be later accessed by other
6943  *    hooks ("allocating" hooks).
6944  *
6945  * Please follow block comment delimiters in the list to keep this order.
6946  *
6947  * This ordering is needed for SELinux runtime disable to work at least somewhat
6948  * safely. Breaking the ordering rules above might lead to NULL pointer derefs
6949  * when disabling SELinux at runtime.
6950  */
6951 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6952 	LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6953 	LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6954 	LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6955 	LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6956 
6957 	LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6958 	LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6959 	LSM_HOOK_INIT(capget, selinux_capget),
6960 	LSM_HOOK_INIT(capset, selinux_capset),
6961 	LSM_HOOK_INIT(capable, selinux_capable),
6962 	LSM_HOOK_INIT(quotactl, selinux_quotactl),
6963 	LSM_HOOK_INIT(quota_on, selinux_quota_on),
6964 	LSM_HOOK_INIT(syslog, selinux_syslog),
6965 	LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6966 
6967 	LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6968 
6969 	LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
6970 	LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6971 	LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6972 
6973 	LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6974 	LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
6975 	LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6976 	LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6977 	LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6978 	LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6979 	LSM_HOOK_INIT(sb_mount, selinux_mount),
6980 	LSM_HOOK_INIT(sb_umount, selinux_umount),
6981 	LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6982 	LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6983 
6984 	LSM_HOOK_INIT(move_mount, selinux_move_mount),
6985 
6986 	LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6987 	LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6988 
6989 	LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6990 	LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6991 	LSM_HOOK_INIT(inode_create, selinux_inode_create),
6992 	LSM_HOOK_INIT(inode_link, selinux_inode_link),
6993 	LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6994 	LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6995 	LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6996 	LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6997 	LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6998 	LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6999 	LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7000 	LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7001 	LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7002 	LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7003 	LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7004 	LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7005 	LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7006 	LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7007 	LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7008 	LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7009 	LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7010 	LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7011 	LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7012 	LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7013 	LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7014 	LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7015 	LSM_HOOK_INIT(path_notify, selinux_path_notify),
7016 
7017 	LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7018 
7019 	LSM_HOOK_INIT(file_permission, selinux_file_permission),
7020 	LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7021 	LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7022 	LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7023 	LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7024 	LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7025 	LSM_HOOK_INIT(file_lock, selinux_file_lock),
7026 	LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7027 	LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7028 	LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7029 	LSM_HOOK_INIT(file_receive, selinux_file_receive),
7030 
7031 	LSM_HOOK_INIT(file_open, selinux_file_open),
7032 
7033 	LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7034 	LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7035 	LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7036 	LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7037 	LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7038 	LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7039 	LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7040 	LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7041 	LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7042 	LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7043 	LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7044 	LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7045 	LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
7046 	LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7047 	LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7048 	LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7049 	LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7050 	LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7051 	LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7052 	LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7053 	LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7054 	LSM_HOOK_INIT(task_kill, selinux_task_kill),
7055 	LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7056 
7057 	LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7058 	LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7059 
7060 	LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7061 	LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7062 	LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7063 	LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7064 
7065 	LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7066 	LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7067 	LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7068 
7069 	LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7070 	LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7071 	LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7072 
7073 	LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7074 
7075 	LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7076 	LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7077 
7078 	LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7079 	LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7080 	LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7081 	LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7082 	LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7083 	LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7084 
7085 	LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7086 	LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7087 
7088 	LSM_HOOK_INIT(socket_create, selinux_socket_create),
7089 	LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7090 	LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7091 	LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7092 	LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7093 	LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7094 	LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7095 	LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7096 	LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7097 	LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7098 	LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7099 	LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7100 	LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7101 	LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7102 	LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7103 	LSM_HOOK_INIT(socket_getpeersec_stream,
7104 			selinux_socket_getpeersec_stream),
7105 	LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7106 	LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7107 	LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7108 	LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7109 	LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7110 	LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7111 	LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7112 	LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7113 	LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7114 	LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7115 	LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7116 	LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7117 	LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7118 	LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7119 	LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7120 	LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7121 	LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7122 	LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7123 	LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7124 	LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7125 #ifdef CONFIG_SECURITY_INFINIBAND
7126 	LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7127 	LSM_HOOK_INIT(ib_endport_manage_subnet,
7128 		      selinux_ib_endport_manage_subnet),
7129 	LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7130 #endif
7131 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7132 	LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7133 	LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7134 	LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7135 	LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7136 	LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7137 	LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7138 			selinux_xfrm_state_pol_flow_match),
7139 	LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7140 #endif
7141 
7142 #ifdef CONFIG_KEYS
7143 	LSM_HOOK_INIT(key_free, selinux_key_free),
7144 	LSM_HOOK_INIT(key_permission, selinux_key_permission),
7145 	LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7146 #ifdef CONFIG_KEY_NOTIFICATIONS
7147 	LSM_HOOK_INIT(watch_key, selinux_watch_key),
7148 #endif
7149 #endif
7150 
7151 #ifdef CONFIG_AUDIT
7152 	LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7153 	LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7154 	LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7155 #endif
7156 
7157 #ifdef CONFIG_BPF_SYSCALL
7158 	LSM_HOOK_INIT(bpf, selinux_bpf),
7159 	LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7160 	LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7161 	LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7162 	LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7163 #endif
7164 
7165 #ifdef CONFIG_PERF_EVENTS
7166 	LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7167 	LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7168 	LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7169 	LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7170 #endif
7171 
7172 	LSM_HOOK_INIT(locked_down, selinux_lockdown),
7173 
7174 	/*
7175 	 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7176 	 */
7177 	LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7178 	LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7179 	LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7180 	LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt),
7181 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7182 	LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7183 #endif
7184 
7185 	/*
7186 	 * PUT "ALLOCATING" HOOKS HERE
7187 	 */
7188 	LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7189 	LSM_HOOK_INIT(msg_queue_alloc_security,
7190 		      selinux_msg_queue_alloc_security),
7191 	LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7192 	LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7193 	LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7194 	LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7195 	LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7196 	LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7197 	LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7198 	LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7199 #ifdef CONFIG_SECURITY_INFINIBAND
7200 	LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7201 #endif
7202 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7203 	LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7204 	LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7205 	LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7206 		      selinux_xfrm_state_alloc_acquire),
7207 #endif
7208 #ifdef CONFIG_KEYS
7209 	LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7210 #endif
7211 #ifdef CONFIG_AUDIT
7212 	LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7213 #endif
7214 #ifdef CONFIG_BPF_SYSCALL
7215 	LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7216 	LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7217 #endif
7218 #ifdef CONFIG_PERF_EVENTS
7219 	LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7220 #endif
7221 };
7222 
7223 static __init int selinux_init(void)
7224 {
7225 	pr_info("SELinux:  Initializing.\n");
7226 
7227 	memset(&selinux_state, 0, sizeof(selinux_state));
7228 	enforcing_set(&selinux_state, selinux_enforcing_boot);
7229 	selinux_state.checkreqprot = selinux_checkreqprot_boot;
7230 	selinux_ss_init(&selinux_state.ss);
7231 	selinux_avc_init(&selinux_state.avc);
7232 	mutex_init(&selinux_state.status_lock);
7233 
7234 	/* Set the security state for the initial task. */
7235 	cred_init_security();
7236 
7237 	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7238 
7239 	avc_init();
7240 
7241 	avtab_cache_init();
7242 
7243 	ebitmap_cache_init();
7244 
7245 	hashtab_cache_init();
7246 
7247 	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7248 
7249 	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7250 		panic("SELinux: Unable to register AVC netcache callback\n");
7251 
7252 	if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7253 		panic("SELinux: Unable to register AVC LSM notifier callback\n");
7254 
7255 	if (selinux_enforcing_boot)
7256 		pr_debug("SELinux:  Starting in enforcing mode\n");
7257 	else
7258 		pr_debug("SELinux:  Starting in permissive mode\n");
7259 
7260 	fs_validate_description("selinux", selinux_fs_parameters);
7261 
7262 	return 0;
7263 }
7264 
7265 static void delayed_superblock_init(struct super_block *sb, void *unused)
7266 {
7267 	selinux_set_mnt_opts(sb, NULL, 0, NULL);
7268 }
7269 
7270 void selinux_complete_init(void)
7271 {
7272 	pr_debug("SELinux:  Completing initialization.\n");
7273 
7274 	/* Set up any superblocks initialized prior to the policy load. */
7275 	pr_debug("SELinux:  Setting up existing superblocks.\n");
7276 	iterate_supers(delayed_superblock_init, NULL);
7277 }
7278 
7279 /* SELinux requires early initialization in order to label
7280    all processes and objects when they are created. */
7281 DEFINE_LSM(selinux) = {
7282 	.name = "selinux",
7283 	.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7284 	.enabled = &selinux_enabled_boot,
7285 	.blobs = &selinux_blob_sizes,
7286 	.init = selinux_init,
7287 };
7288 
7289 #if defined(CONFIG_NETFILTER)
7290 
7291 static const struct nf_hook_ops selinux_nf_ops[] = {
7292 	{
7293 		.hook =		selinux_ipv4_postroute,
7294 		.pf =		NFPROTO_IPV4,
7295 		.hooknum =	NF_INET_POST_ROUTING,
7296 		.priority =	NF_IP_PRI_SELINUX_LAST,
7297 	},
7298 	{
7299 		.hook =		selinux_ipv4_forward,
7300 		.pf =		NFPROTO_IPV4,
7301 		.hooknum =	NF_INET_FORWARD,
7302 		.priority =	NF_IP_PRI_SELINUX_FIRST,
7303 	},
7304 	{
7305 		.hook =		selinux_ipv4_output,
7306 		.pf =		NFPROTO_IPV4,
7307 		.hooknum =	NF_INET_LOCAL_OUT,
7308 		.priority =	NF_IP_PRI_SELINUX_FIRST,
7309 	},
7310 #if IS_ENABLED(CONFIG_IPV6)
7311 	{
7312 		.hook =		selinux_ipv6_postroute,
7313 		.pf =		NFPROTO_IPV6,
7314 		.hooknum =	NF_INET_POST_ROUTING,
7315 		.priority =	NF_IP6_PRI_SELINUX_LAST,
7316 	},
7317 	{
7318 		.hook =		selinux_ipv6_forward,
7319 		.pf =		NFPROTO_IPV6,
7320 		.hooknum =	NF_INET_FORWARD,
7321 		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7322 	},
7323 	{
7324 		.hook =		selinux_ipv6_output,
7325 		.pf =		NFPROTO_IPV6,
7326 		.hooknum =	NF_INET_LOCAL_OUT,
7327 		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7328 	},
7329 #endif	/* IPV6 */
7330 };
7331 
7332 static int __net_init selinux_nf_register(struct net *net)
7333 {
7334 	return nf_register_net_hooks(net, selinux_nf_ops,
7335 				     ARRAY_SIZE(selinux_nf_ops));
7336 }
7337 
7338 static void __net_exit selinux_nf_unregister(struct net *net)
7339 {
7340 	nf_unregister_net_hooks(net, selinux_nf_ops,
7341 				ARRAY_SIZE(selinux_nf_ops));
7342 }
7343 
7344 static struct pernet_operations selinux_net_ops = {
7345 	.init = selinux_nf_register,
7346 	.exit = selinux_nf_unregister,
7347 };
7348 
7349 static int __init selinux_nf_ip_init(void)
7350 {
7351 	int err;
7352 
7353 	if (!selinux_enabled_boot)
7354 		return 0;
7355 
7356 	pr_debug("SELinux:  Registering netfilter hooks\n");
7357 
7358 	err = register_pernet_subsys(&selinux_net_ops);
7359 	if (err)
7360 		panic("SELinux: register_pernet_subsys: error %d\n", err);
7361 
7362 	return 0;
7363 }
7364 __initcall(selinux_nf_ip_init);
7365 
7366 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7367 static void selinux_nf_ip_exit(void)
7368 {
7369 	pr_debug("SELinux:  Unregistering netfilter hooks\n");
7370 
7371 	unregister_pernet_subsys(&selinux_net_ops);
7372 }
7373 #endif
7374 
7375 #else /* CONFIG_NETFILTER */
7376 
7377 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7378 #define selinux_nf_ip_exit()
7379 #endif
7380 
7381 #endif /* CONFIG_NETFILTER */
7382 
7383 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7384 int selinux_disable(struct selinux_state *state)
7385 {
7386 	if (selinux_initialized(state)) {
7387 		/* Not permitted after initial policy load. */
7388 		return -EINVAL;
7389 	}
7390 
7391 	if (selinux_disabled(state)) {
7392 		/* Only do this once. */
7393 		return -EINVAL;
7394 	}
7395 
7396 	selinux_mark_disabled(state);
7397 
7398 	pr_info("SELinux:  Disabled at runtime.\n");
7399 
7400 	/*
7401 	 * Unregister netfilter hooks.
7402 	 * Must be done before security_delete_hooks() to avoid breaking
7403 	 * runtime disable.
7404 	 */
7405 	selinux_nf_ip_exit();
7406 
7407 	security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7408 
7409 	/* Try to destroy the avc node cache */
7410 	avc_disable();
7411 
7412 	/* Unregister selinuxfs. */
7413 	exit_sel_fs();
7414 
7415 	return 0;
7416 }
7417 #endif
7418