xref: /openbmc/linux/security/selinux/hooks.c (revision d0e22329)
1 /*
2  *  NSA Security-Enhanced Linux (SELinux) security module
3  *
4  *  This file contains the SELinux hook function implementations.
5  *
6  *  Authors:  Stephen Smalley, <sds@tycho.nsa.gov>
7  *	      Chris Vance, <cvance@nai.com>
8  *	      Wayne Salamon, <wsalamon@nai.com>
9  *	      James Morris <jmorris@redhat.com>
10  *
11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13  *					   Eric Paris <eparis@redhat.com>
14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15  *			    <dgoeddel@trustedcs.com>
16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17  *	Paul Moore <paul@paul-moore.com>
18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19  *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
20  *  Copyright (C) 2016 Mellanox Technologies
21  *
22  *	This program is free software; you can redistribute it and/or modify
23  *	it under the terms of the GNU General Public License version 2,
24  *	as published by the Free Software Foundation.
25  */
26 
27 #include <linux/init.h>
28 #include <linux/kd.h>
29 #include <linux/kernel.h>
30 #include <linux/tracehook.h>
31 #include <linux/errno.h>
32 #include <linux/sched/signal.h>
33 #include <linux/sched/task.h>
34 #include <linux/lsm_hooks.h>
35 #include <linux/xattr.h>
36 #include <linux/capability.h>
37 #include <linux/unistd.h>
38 #include <linux/mm.h>
39 #include <linux/mman.h>
40 #include <linux/slab.h>
41 #include <linux/pagemap.h>
42 #include <linux/proc_fs.h>
43 #include <linux/swap.h>
44 #include <linux/spinlock.h>
45 #include <linux/syscalls.h>
46 #include <linux/dcache.h>
47 #include <linux/file.h>
48 #include <linux/fdtable.h>
49 #include <linux/namei.h>
50 #include <linux/mount.h>
51 #include <linux/netfilter_ipv4.h>
52 #include <linux/netfilter_ipv6.h>
53 #include <linux/tty.h>
54 #include <net/icmp.h>
55 #include <net/ip.h>		/* for local_port_range[] */
56 #include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
57 #include <net/inet_connection_sock.h>
58 #include <net/net_namespace.h>
59 #include <net/netlabel.h>
60 #include <linux/uaccess.h>
61 #include <asm/ioctls.h>
62 #include <linux/atomic.h>
63 #include <linux/bitops.h>
64 #include <linux/interrupt.h>
65 #include <linux/netdevice.h>	/* for network interface checks */
66 #include <net/netlink.h>
67 #include <linux/tcp.h>
68 #include <linux/udp.h>
69 #include <linux/dccp.h>
70 #include <linux/sctp.h>
71 #include <net/sctp/structs.h>
72 #include <linux/quota.h>
73 #include <linux/un.h>		/* for Unix socket types */
74 #include <net/af_unix.h>	/* for Unix socket types */
75 #include <linux/parser.h>
76 #include <linux/nfs_mount.h>
77 #include <net/ipv6.h>
78 #include <linux/hugetlb.h>
79 #include <linux/personality.h>
80 #include <linux/audit.h>
81 #include <linux/string.h>
82 #include <linux/selinux.h>
83 #include <linux/mutex.h>
84 #include <linux/posix-timers.h>
85 #include <linux/syslog.h>
86 #include <linux/user_namespace.h>
87 #include <linux/export.h>
88 #include <linux/msg.h>
89 #include <linux/shm.h>
90 #include <linux/bpf.h>
91 #include <uapi/linux/mount.h>
92 
93 #include "avc.h"
94 #include "objsec.h"
95 #include "netif.h"
96 #include "netnode.h"
97 #include "netport.h"
98 #include "ibpkey.h"
99 #include "xfrm.h"
100 #include "netlabel.h"
101 #include "audit.h"
102 #include "avc_ss.h"
103 
104 struct selinux_state selinux_state;
105 
106 /* SECMARK reference count */
107 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
108 
109 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
110 static int selinux_enforcing_boot;
111 
112 static int __init enforcing_setup(char *str)
113 {
114 	unsigned long enforcing;
115 	if (!kstrtoul(str, 0, &enforcing))
116 		selinux_enforcing_boot = enforcing ? 1 : 0;
117 	return 1;
118 }
119 __setup("enforcing=", enforcing_setup);
120 #else
121 #define selinux_enforcing_boot 1
122 #endif
123 
124 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
125 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
126 
127 static int __init selinux_enabled_setup(char *str)
128 {
129 	unsigned long enabled;
130 	if (!kstrtoul(str, 0, &enabled))
131 		selinux_enabled = enabled ? 1 : 0;
132 	return 1;
133 }
134 __setup("selinux=", selinux_enabled_setup);
135 #else
136 int selinux_enabled = 1;
137 #endif
138 
139 static unsigned int selinux_checkreqprot_boot =
140 	CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
141 
142 static int __init checkreqprot_setup(char *str)
143 {
144 	unsigned long checkreqprot;
145 
146 	if (!kstrtoul(str, 0, &checkreqprot))
147 		selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
148 	return 1;
149 }
150 __setup("checkreqprot=", checkreqprot_setup);
151 
152 static struct kmem_cache *sel_inode_cache;
153 static struct kmem_cache *file_security_cache;
154 
155 /**
156  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
157  *
158  * Description:
159  * This function checks the SECMARK reference counter to see if any SECMARK
160  * targets are currently configured, if the reference counter is greater than
161  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
162  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
163  * policy capability is enabled, SECMARK is always considered enabled.
164  *
165  */
166 static int selinux_secmark_enabled(void)
167 {
168 	return (selinux_policycap_alwaysnetwork() ||
169 		atomic_read(&selinux_secmark_refcount));
170 }
171 
172 /**
173  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
174  *
175  * Description:
176  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
177  * (1) if any are enabled or false (0) if neither are enabled.  If the
178  * always_check_network policy capability is enabled, peer labeling
179  * is always considered enabled.
180  *
181  */
182 static int selinux_peerlbl_enabled(void)
183 {
184 	return (selinux_policycap_alwaysnetwork() ||
185 		netlbl_enabled() || selinux_xfrm_enabled());
186 }
187 
188 static int selinux_netcache_avc_callback(u32 event)
189 {
190 	if (event == AVC_CALLBACK_RESET) {
191 		sel_netif_flush();
192 		sel_netnode_flush();
193 		sel_netport_flush();
194 		synchronize_net();
195 	}
196 	return 0;
197 }
198 
199 static int selinux_lsm_notifier_avc_callback(u32 event)
200 {
201 	if (event == AVC_CALLBACK_RESET) {
202 		sel_ib_pkey_flush();
203 		call_lsm_notifier(LSM_POLICY_CHANGE, NULL);
204 	}
205 
206 	return 0;
207 }
208 
209 /*
210  * initialise the security for the init task
211  */
212 static void cred_init_security(void)
213 {
214 	struct cred *cred = (struct cred *) current->real_cred;
215 	struct task_security_struct *tsec;
216 
217 	tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
218 	if (!tsec)
219 		panic("SELinux:  Failed to initialize initial task.\n");
220 
221 	tsec->osid = tsec->sid = SECINITSID_KERNEL;
222 	cred->security = tsec;
223 }
224 
225 /*
226  * get the security ID of a set of credentials
227  */
228 static inline u32 cred_sid(const struct cred *cred)
229 {
230 	const struct task_security_struct *tsec;
231 
232 	tsec = cred->security;
233 	return tsec->sid;
234 }
235 
236 /*
237  * get the objective security ID of a task
238  */
239 static inline u32 task_sid(const struct task_struct *task)
240 {
241 	u32 sid;
242 
243 	rcu_read_lock();
244 	sid = cred_sid(__task_cred(task));
245 	rcu_read_unlock();
246 	return sid;
247 }
248 
249 /* Allocate and free functions for each kind of security blob. */
250 
251 static int inode_alloc_security(struct inode *inode)
252 {
253 	struct inode_security_struct *isec;
254 	u32 sid = current_sid();
255 
256 	isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
257 	if (!isec)
258 		return -ENOMEM;
259 
260 	spin_lock_init(&isec->lock);
261 	INIT_LIST_HEAD(&isec->list);
262 	isec->inode = inode;
263 	isec->sid = SECINITSID_UNLABELED;
264 	isec->sclass = SECCLASS_FILE;
265 	isec->task_sid = sid;
266 	isec->initialized = LABEL_INVALID;
267 	inode->i_security = isec;
268 
269 	return 0;
270 }
271 
272 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
273 
274 /*
275  * Try reloading inode security labels that have been marked as invalid.  The
276  * @may_sleep parameter indicates when sleeping and thus reloading labels is
277  * allowed; when set to false, returns -ECHILD when the label is
278  * invalid.  The @dentry parameter should be set to a dentry of the inode.
279  */
280 static int __inode_security_revalidate(struct inode *inode,
281 				       struct dentry *dentry,
282 				       bool may_sleep)
283 {
284 	struct inode_security_struct *isec = inode->i_security;
285 
286 	might_sleep_if(may_sleep);
287 
288 	if (selinux_state.initialized &&
289 	    isec->initialized != LABEL_INITIALIZED) {
290 		if (!may_sleep)
291 			return -ECHILD;
292 
293 		/*
294 		 * Try reloading the inode security label.  This will fail if
295 		 * @opt_dentry is NULL and no dentry for this inode can be
296 		 * found; in that case, continue using the old label.
297 		 */
298 		inode_doinit_with_dentry(inode, dentry);
299 	}
300 	return 0;
301 }
302 
303 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
304 {
305 	return inode->i_security;
306 }
307 
308 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
309 {
310 	int error;
311 
312 	error = __inode_security_revalidate(inode, NULL, !rcu);
313 	if (error)
314 		return ERR_PTR(error);
315 	return inode->i_security;
316 }
317 
318 /*
319  * Get the security label of an inode.
320  */
321 static struct inode_security_struct *inode_security(struct inode *inode)
322 {
323 	__inode_security_revalidate(inode, NULL, true);
324 	return inode->i_security;
325 }
326 
327 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
328 {
329 	struct inode *inode = d_backing_inode(dentry);
330 
331 	return inode->i_security;
332 }
333 
334 /*
335  * Get the security label of a dentry's backing inode.
336  */
337 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
338 {
339 	struct inode *inode = d_backing_inode(dentry);
340 
341 	__inode_security_revalidate(inode, dentry, true);
342 	return inode->i_security;
343 }
344 
345 static void inode_free_rcu(struct rcu_head *head)
346 {
347 	struct inode_security_struct *isec;
348 
349 	isec = container_of(head, struct inode_security_struct, rcu);
350 	kmem_cache_free(sel_inode_cache, isec);
351 }
352 
353 static void inode_free_security(struct inode *inode)
354 {
355 	struct inode_security_struct *isec = inode->i_security;
356 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
357 
358 	/*
359 	 * As not all inode security structures are in a list, we check for
360 	 * empty list outside of the lock to make sure that we won't waste
361 	 * time taking a lock doing nothing.
362 	 *
363 	 * The list_del_init() function can be safely called more than once.
364 	 * It should not be possible for this function to be called with
365 	 * concurrent list_add(), but for better safety against future changes
366 	 * in the code, we use list_empty_careful() here.
367 	 */
368 	if (!list_empty_careful(&isec->list)) {
369 		spin_lock(&sbsec->isec_lock);
370 		list_del_init(&isec->list);
371 		spin_unlock(&sbsec->isec_lock);
372 	}
373 
374 	/*
375 	 * The inode may still be referenced in a path walk and
376 	 * a call to selinux_inode_permission() can be made
377 	 * after inode_free_security() is called. Ideally, the VFS
378 	 * wouldn't do this, but fixing that is a much harder
379 	 * job. For now, simply free the i_security via RCU, and
380 	 * leave the current inode->i_security pointer intact.
381 	 * The inode will be freed after the RCU grace period too.
382 	 */
383 	call_rcu(&isec->rcu, inode_free_rcu);
384 }
385 
386 static int file_alloc_security(struct file *file)
387 {
388 	struct file_security_struct *fsec;
389 	u32 sid = current_sid();
390 
391 	fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
392 	if (!fsec)
393 		return -ENOMEM;
394 
395 	fsec->sid = sid;
396 	fsec->fown_sid = sid;
397 	file->f_security = fsec;
398 
399 	return 0;
400 }
401 
402 static void file_free_security(struct file *file)
403 {
404 	struct file_security_struct *fsec = file->f_security;
405 	file->f_security = NULL;
406 	kmem_cache_free(file_security_cache, fsec);
407 }
408 
409 static int superblock_alloc_security(struct super_block *sb)
410 {
411 	struct superblock_security_struct *sbsec;
412 
413 	sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
414 	if (!sbsec)
415 		return -ENOMEM;
416 
417 	mutex_init(&sbsec->lock);
418 	INIT_LIST_HEAD(&sbsec->isec_head);
419 	spin_lock_init(&sbsec->isec_lock);
420 	sbsec->sb = sb;
421 	sbsec->sid = SECINITSID_UNLABELED;
422 	sbsec->def_sid = SECINITSID_FILE;
423 	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
424 	sb->s_security = sbsec;
425 
426 	return 0;
427 }
428 
429 static void superblock_free_security(struct super_block *sb)
430 {
431 	struct superblock_security_struct *sbsec = sb->s_security;
432 	sb->s_security = NULL;
433 	kfree(sbsec);
434 }
435 
436 struct selinux_mnt_opts {
437 	const char *fscontext, *context, *rootcontext, *defcontext;
438 };
439 
440 static void selinux_free_mnt_opts(void *mnt_opts)
441 {
442 	struct selinux_mnt_opts *opts = mnt_opts;
443 	kfree(opts->fscontext);
444 	kfree(opts->context);
445 	kfree(opts->rootcontext);
446 	kfree(opts->defcontext);
447 	kfree(opts);
448 }
449 
450 static inline int inode_doinit(struct inode *inode)
451 {
452 	return inode_doinit_with_dentry(inode, NULL);
453 }
454 
455 enum {
456 	Opt_error = -1,
457 	Opt_context = 1,
458 	Opt_fscontext = 2,
459 	Opt_defcontext = 3,
460 	Opt_rootcontext = 4,
461 	Opt_seclabel = 5,
462 };
463 
464 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
465 static struct {
466 	const char *name;
467 	int len;
468 	int opt;
469 	bool has_arg;
470 } tokens[] = {
471 	A(context, true),
472 	A(fscontext, true),
473 	A(defcontext, true),
474 	A(rootcontext, true),
475 	A(seclabel, false),
476 };
477 #undef A
478 
479 static int match_opt_prefix(char *s, int l, char **arg)
480 {
481 	int i;
482 
483 	for (i = 0; i < ARRAY_SIZE(tokens); i++) {
484 		size_t len = tokens[i].len;
485 		if (len > l || memcmp(s, tokens[i].name, len))
486 			continue;
487 		if (tokens[i].has_arg) {
488 			if (len == l || s[len] != '=')
489 				continue;
490 			*arg = s + len + 1;
491 		} else if (len != l)
492 			continue;
493 		return tokens[i].opt;
494 	}
495 	return Opt_error;
496 }
497 
498 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
499 
500 static int may_context_mount_sb_relabel(u32 sid,
501 			struct superblock_security_struct *sbsec,
502 			const struct cred *cred)
503 {
504 	const struct task_security_struct *tsec = cred->security;
505 	int rc;
506 
507 	rc = avc_has_perm(&selinux_state,
508 			  tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
509 			  FILESYSTEM__RELABELFROM, NULL);
510 	if (rc)
511 		return rc;
512 
513 	rc = avc_has_perm(&selinux_state,
514 			  tsec->sid, sid, SECCLASS_FILESYSTEM,
515 			  FILESYSTEM__RELABELTO, NULL);
516 	return rc;
517 }
518 
519 static int may_context_mount_inode_relabel(u32 sid,
520 			struct superblock_security_struct *sbsec,
521 			const struct cred *cred)
522 {
523 	const struct task_security_struct *tsec = cred->security;
524 	int rc;
525 	rc = avc_has_perm(&selinux_state,
526 			  tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
527 			  FILESYSTEM__RELABELFROM, NULL);
528 	if (rc)
529 		return rc;
530 
531 	rc = avc_has_perm(&selinux_state,
532 			  sid, sbsec->sid, SECCLASS_FILESYSTEM,
533 			  FILESYSTEM__ASSOCIATE, NULL);
534 	return rc;
535 }
536 
537 static int selinux_is_sblabel_mnt(struct super_block *sb)
538 {
539 	struct superblock_security_struct *sbsec = sb->s_security;
540 
541 	return sbsec->behavior == SECURITY_FS_USE_XATTR ||
542 		sbsec->behavior == SECURITY_FS_USE_TRANS ||
543 		sbsec->behavior == SECURITY_FS_USE_TASK ||
544 		sbsec->behavior == SECURITY_FS_USE_NATIVE ||
545 		/* Special handling. Genfs but also in-core setxattr handler */
546 		!strcmp(sb->s_type->name, "sysfs") ||
547 		!strcmp(sb->s_type->name, "pstore") ||
548 		!strcmp(sb->s_type->name, "debugfs") ||
549 		!strcmp(sb->s_type->name, "tracefs") ||
550 		!strcmp(sb->s_type->name, "rootfs") ||
551 		(selinux_policycap_cgroupseclabel() &&
552 		 (!strcmp(sb->s_type->name, "cgroup") ||
553 		  !strcmp(sb->s_type->name, "cgroup2")));
554 }
555 
556 static int sb_finish_set_opts(struct super_block *sb)
557 {
558 	struct superblock_security_struct *sbsec = sb->s_security;
559 	struct dentry *root = sb->s_root;
560 	struct inode *root_inode = d_backing_inode(root);
561 	int rc = 0;
562 
563 	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
564 		/* Make sure that the xattr handler exists and that no
565 		   error other than -ENODATA is returned by getxattr on
566 		   the root directory.  -ENODATA is ok, as this may be
567 		   the first boot of the SELinux kernel before we have
568 		   assigned xattr values to the filesystem. */
569 		if (!(root_inode->i_opflags & IOP_XATTR)) {
570 			pr_warn("SELinux: (dev %s, type %s) has no "
571 			       "xattr support\n", sb->s_id, sb->s_type->name);
572 			rc = -EOPNOTSUPP;
573 			goto out;
574 		}
575 
576 		rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
577 		if (rc < 0 && rc != -ENODATA) {
578 			if (rc == -EOPNOTSUPP)
579 				pr_warn("SELinux: (dev %s, type "
580 				       "%s) has no security xattr handler\n",
581 				       sb->s_id, sb->s_type->name);
582 			else
583 				pr_warn("SELinux: (dev %s, type "
584 				       "%s) getxattr errno %d\n", sb->s_id,
585 				       sb->s_type->name, -rc);
586 			goto out;
587 		}
588 	}
589 
590 	sbsec->flags |= SE_SBINITIALIZED;
591 
592 	/*
593 	 * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
594 	 * leave the flag untouched because sb_clone_mnt_opts might be handing
595 	 * us a superblock that needs the flag to be cleared.
596 	 */
597 	if (selinux_is_sblabel_mnt(sb))
598 		sbsec->flags |= SBLABEL_MNT;
599 	else
600 		sbsec->flags &= ~SBLABEL_MNT;
601 
602 	/* Initialize the root inode. */
603 	rc = inode_doinit_with_dentry(root_inode, root);
604 
605 	/* Initialize any other inodes associated with the superblock, e.g.
606 	   inodes created prior to initial policy load or inodes created
607 	   during get_sb by a pseudo filesystem that directly
608 	   populates itself. */
609 	spin_lock(&sbsec->isec_lock);
610 	while (!list_empty(&sbsec->isec_head)) {
611 		struct inode_security_struct *isec =
612 				list_first_entry(&sbsec->isec_head,
613 					   struct inode_security_struct, list);
614 		struct inode *inode = isec->inode;
615 		list_del_init(&isec->list);
616 		spin_unlock(&sbsec->isec_lock);
617 		inode = igrab(inode);
618 		if (inode) {
619 			if (!IS_PRIVATE(inode))
620 				inode_doinit(inode);
621 			iput(inode);
622 		}
623 		spin_lock(&sbsec->isec_lock);
624 	}
625 	spin_unlock(&sbsec->isec_lock);
626 out:
627 	return rc;
628 }
629 
630 static int bad_option(struct superblock_security_struct *sbsec, char flag,
631 		      u32 old_sid, u32 new_sid)
632 {
633 	char mnt_flags = sbsec->flags & SE_MNTMASK;
634 
635 	/* check if the old mount command had the same options */
636 	if (sbsec->flags & SE_SBINITIALIZED)
637 		if (!(sbsec->flags & flag) ||
638 		    (old_sid != new_sid))
639 			return 1;
640 
641 	/* check if we were passed the same options twice,
642 	 * aka someone passed context=a,context=b
643 	 */
644 	if (!(sbsec->flags & SE_SBINITIALIZED))
645 		if (mnt_flags & flag)
646 			return 1;
647 	return 0;
648 }
649 
650 static int parse_sid(struct super_block *sb, const char *s, u32 *sid)
651 {
652 	int rc = security_context_str_to_sid(&selinux_state, s,
653 					     sid, GFP_KERNEL);
654 	if (rc)
655 		pr_warn("SELinux: security_context_str_to_sid"
656 		       "(%s) failed for (dev %s, type %s) errno=%d\n",
657 		       s, sb->s_id, sb->s_type->name, rc);
658 	return rc;
659 }
660 
661 /*
662  * Allow filesystems with binary mount data to explicitly set mount point
663  * labeling information.
664  */
665 static int selinux_set_mnt_opts(struct super_block *sb,
666 				void *mnt_opts,
667 				unsigned long kern_flags,
668 				unsigned long *set_kern_flags)
669 {
670 	const struct cred *cred = current_cred();
671 	struct superblock_security_struct *sbsec = sb->s_security;
672 	struct dentry *root = sbsec->sb->s_root;
673 	struct selinux_mnt_opts *opts = mnt_opts;
674 	struct inode_security_struct *root_isec;
675 	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
676 	u32 defcontext_sid = 0;
677 	int rc = 0;
678 
679 	mutex_lock(&sbsec->lock);
680 
681 	if (!selinux_state.initialized) {
682 		if (!opts) {
683 			/* Defer initialization until selinux_complete_init,
684 			   after the initial policy is loaded and the security
685 			   server is ready to handle calls. */
686 			goto out;
687 		}
688 		rc = -EINVAL;
689 		pr_warn("SELinux: Unable to set superblock options "
690 			"before the security server is initialized\n");
691 		goto out;
692 	}
693 	if (kern_flags && !set_kern_flags) {
694 		/* Specifying internal flags without providing a place to
695 		 * place the results is not allowed */
696 		rc = -EINVAL;
697 		goto out;
698 	}
699 
700 	/*
701 	 * Binary mount data FS will come through this function twice.  Once
702 	 * from an explicit call and once from the generic calls from the vfs.
703 	 * Since the generic VFS calls will not contain any security mount data
704 	 * we need to skip the double mount verification.
705 	 *
706 	 * This does open a hole in which we will not notice if the first
707 	 * mount using this sb set explict options and a second mount using
708 	 * this sb does not set any security options.  (The first options
709 	 * will be used for both mounts)
710 	 */
711 	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
712 	    && !opts)
713 		goto out;
714 
715 	root_isec = backing_inode_security_novalidate(root);
716 
717 	/*
718 	 * parse the mount options, check if they are valid sids.
719 	 * also check if someone is trying to mount the same sb more
720 	 * than once with different security options.
721 	 */
722 	if (opts) {
723 		if (opts->fscontext) {
724 			rc = parse_sid(sb, opts->fscontext, &fscontext_sid);
725 			if (rc)
726 				goto out;
727 			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
728 					fscontext_sid))
729 				goto out_double_mount;
730 			sbsec->flags |= FSCONTEXT_MNT;
731 		}
732 		if (opts->context) {
733 			rc = parse_sid(sb, opts->context, &context_sid);
734 			if (rc)
735 				goto out;
736 			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
737 					context_sid))
738 				goto out_double_mount;
739 			sbsec->flags |= CONTEXT_MNT;
740 		}
741 		if (opts->rootcontext) {
742 			rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid);
743 			if (rc)
744 				goto out;
745 			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
746 					rootcontext_sid))
747 				goto out_double_mount;
748 			sbsec->flags |= ROOTCONTEXT_MNT;
749 		}
750 		if (opts->defcontext) {
751 			rc = parse_sid(sb, opts->defcontext, &defcontext_sid);
752 			if (rc)
753 				goto out;
754 			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
755 					defcontext_sid))
756 				goto out_double_mount;
757 			sbsec->flags |= DEFCONTEXT_MNT;
758 		}
759 	}
760 
761 	if (sbsec->flags & SE_SBINITIALIZED) {
762 		/* previously mounted with options, but not on this attempt? */
763 		if ((sbsec->flags & SE_MNTMASK) && !opts)
764 			goto out_double_mount;
765 		rc = 0;
766 		goto out;
767 	}
768 
769 	if (strcmp(sb->s_type->name, "proc") == 0)
770 		sbsec->flags |= SE_SBPROC | SE_SBGENFS;
771 
772 	if (!strcmp(sb->s_type->name, "debugfs") ||
773 	    !strcmp(sb->s_type->name, "tracefs") ||
774 	    !strcmp(sb->s_type->name, "sysfs") ||
775 	    !strcmp(sb->s_type->name, "pstore") ||
776 	    !strcmp(sb->s_type->name, "cgroup") ||
777 	    !strcmp(sb->s_type->name, "cgroup2"))
778 		sbsec->flags |= SE_SBGENFS;
779 
780 	if (!sbsec->behavior) {
781 		/*
782 		 * Determine the labeling behavior to use for this
783 		 * filesystem type.
784 		 */
785 		rc = security_fs_use(&selinux_state, sb);
786 		if (rc) {
787 			pr_warn("%s: security_fs_use(%s) returned %d\n",
788 					__func__, sb->s_type->name, rc);
789 			goto out;
790 		}
791 	}
792 
793 	/*
794 	 * If this is a user namespace mount and the filesystem type is not
795 	 * explicitly whitelisted, then no contexts are allowed on the command
796 	 * line and security labels must be ignored.
797 	 */
798 	if (sb->s_user_ns != &init_user_ns &&
799 	    strcmp(sb->s_type->name, "tmpfs") &&
800 	    strcmp(sb->s_type->name, "ramfs") &&
801 	    strcmp(sb->s_type->name, "devpts")) {
802 		if (context_sid || fscontext_sid || rootcontext_sid ||
803 		    defcontext_sid) {
804 			rc = -EACCES;
805 			goto out;
806 		}
807 		if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
808 			sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
809 			rc = security_transition_sid(&selinux_state,
810 						     current_sid(),
811 						     current_sid(),
812 						     SECCLASS_FILE, NULL,
813 						     &sbsec->mntpoint_sid);
814 			if (rc)
815 				goto out;
816 		}
817 		goto out_set_opts;
818 	}
819 
820 	/* sets the context of the superblock for the fs being mounted. */
821 	if (fscontext_sid) {
822 		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
823 		if (rc)
824 			goto out;
825 
826 		sbsec->sid = fscontext_sid;
827 	}
828 
829 	/*
830 	 * Switch to using mount point labeling behavior.
831 	 * sets the label used on all file below the mountpoint, and will set
832 	 * the superblock context if not already set.
833 	 */
834 	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
835 		sbsec->behavior = SECURITY_FS_USE_NATIVE;
836 		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
837 	}
838 
839 	if (context_sid) {
840 		if (!fscontext_sid) {
841 			rc = may_context_mount_sb_relabel(context_sid, sbsec,
842 							  cred);
843 			if (rc)
844 				goto out;
845 			sbsec->sid = context_sid;
846 		} else {
847 			rc = may_context_mount_inode_relabel(context_sid, sbsec,
848 							     cred);
849 			if (rc)
850 				goto out;
851 		}
852 		if (!rootcontext_sid)
853 			rootcontext_sid = context_sid;
854 
855 		sbsec->mntpoint_sid = context_sid;
856 		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
857 	}
858 
859 	if (rootcontext_sid) {
860 		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
861 						     cred);
862 		if (rc)
863 			goto out;
864 
865 		root_isec->sid = rootcontext_sid;
866 		root_isec->initialized = LABEL_INITIALIZED;
867 	}
868 
869 	if (defcontext_sid) {
870 		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
871 			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
872 			rc = -EINVAL;
873 			pr_warn("SELinux: defcontext option is "
874 			       "invalid for this filesystem type\n");
875 			goto out;
876 		}
877 
878 		if (defcontext_sid != sbsec->def_sid) {
879 			rc = may_context_mount_inode_relabel(defcontext_sid,
880 							     sbsec, cred);
881 			if (rc)
882 				goto out;
883 		}
884 
885 		sbsec->def_sid = defcontext_sid;
886 	}
887 
888 out_set_opts:
889 	rc = sb_finish_set_opts(sb);
890 out:
891 	mutex_unlock(&sbsec->lock);
892 	return rc;
893 out_double_mount:
894 	rc = -EINVAL;
895 	pr_warn("SELinux: mount invalid.  Same superblock, different "
896 	       "security settings for (dev %s, type %s)\n", sb->s_id,
897 	       sb->s_type->name);
898 	goto out;
899 }
900 
901 static int selinux_cmp_sb_context(const struct super_block *oldsb,
902 				    const struct super_block *newsb)
903 {
904 	struct superblock_security_struct *old = oldsb->s_security;
905 	struct superblock_security_struct *new = newsb->s_security;
906 	char oldflags = old->flags & SE_MNTMASK;
907 	char newflags = new->flags & SE_MNTMASK;
908 
909 	if (oldflags != newflags)
910 		goto mismatch;
911 	if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
912 		goto mismatch;
913 	if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
914 		goto mismatch;
915 	if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
916 		goto mismatch;
917 	if (oldflags & ROOTCONTEXT_MNT) {
918 		struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
919 		struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
920 		if (oldroot->sid != newroot->sid)
921 			goto mismatch;
922 	}
923 	return 0;
924 mismatch:
925 	pr_warn("SELinux: mount invalid.  Same superblock, "
926 			    "different security settings for (dev %s, "
927 			    "type %s)\n", newsb->s_id, newsb->s_type->name);
928 	return -EBUSY;
929 }
930 
931 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
932 					struct super_block *newsb,
933 					unsigned long kern_flags,
934 					unsigned long *set_kern_flags)
935 {
936 	int rc = 0;
937 	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
938 	struct superblock_security_struct *newsbsec = newsb->s_security;
939 
940 	int set_fscontext =	(oldsbsec->flags & FSCONTEXT_MNT);
941 	int set_context =	(oldsbsec->flags & CONTEXT_MNT);
942 	int set_rootcontext =	(oldsbsec->flags & ROOTCONTEXT_MNT);
943 
944 	/*
945 	 * if the parent was able to be mounted it clearly had no special lsm
946 	 * mount options.  thus we can safely deal with this superblock later
947 	 */
948 	if (!selinux_state.initialized)
949 		return 0;
950 
951 	/*
952 	 * Specifying internal flags without providing a place to
953 	 * place the results is not allowed.
954 	 */
955 	if (kern_flags && !set_kern_flags)
956 		return -EINVAL;
957 
958 	/* how can we clone if the old one wasn't set up?? */
959 	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
960 
961 	/* if fs is reusing a sb, make sure that the contexts match */
962 	if (newsbsec->flags & SE_SBINITIALIZED)
963 		return selinux_cmp_sb_context(oldsb, newsb);
964 
965 	mutex_lock(&newsbsec->lock);
966 
967 	newsbsec->flags = oldsbsec->flags;
968 
969 	newsbsec->sid = oldsbsec->sid;
970 	newsbsec->def_sid = oldsbsec->def_sid;
971 	newsbsec->behavior = oldsbsec->behavior;
972 
973 	if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
974 		!(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
975 		rc = security_fs_use(&selinux_state, newsb);
976 		if (rc)
977 			goto out;
978 	}
979 
980 	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
981 		newsbsec->behavior = SECURITY_FS_USE_NATIVE;
982 		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
983 	}
984 
985 	if (set_context) {
986 		u32 sid = oldsbsec->mntpoint_sid;
987 
988 		if (!set_fscontext)
989 			newsbsec->sid = sid;
990 		if (!set_rootcontext) {
991 			struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
992 			newisec->sid = sid;
993 		}
994 		newsbsec->mntpoint_sid = sid;
995 	}
996 	if (set_rootcontext) {
997 		const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
998 		struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
999 
1000 		newisec->sid = oldisec->sid;
1001 	}
1002 
1003 	sb_finish_set_opts(newsb);
1004 out:
1005 	mutex_unlock(&newsbsec->lock);
1006 	return rc;
1007 }
1008 
1009 static int selinux_add_opt(int token, const char *s, void **mnt_opts)
1010 {
1011 	struct selinux_mnt_opts *opts = *mnt_opts;
1012 
1013 	if (token == Opt_seclabel)	/* eaten and completely ignored */
1014 		return 0;
1015 
1016 	if (!opts) {
1017 		opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
1018 		if (!opts)
1019 			return -ENOMEM;
1020 		*mnt_opts = opts;
1021 	}
1022 	if (!s)
1023 		return -ENOMEM;
1024 	switch (token) {
1025 	case Opt_context:
1026 		if (opts->context || opts->defcontext)
1027 			goto Einval;
1028 		opts->context = s;
1029 		break;
1030 	case Opt_fscontext:
1031 		if (opts->fscontext)
1032 			goto Einval;
1033 		opts->fscontext = s;
1034 		break;
1035 	case Opt_rootcontext:
1036 		if (opts->rootcontext)
1037 			goto Einval;
1038 		opts->rootcontext = s;
1039 		break;
1040 	case Opt_defcontext:
1041 		if (opts->context || opts->defcontext)
1042 			goto Einval;
1043 		opts->defcontext = s;
1044 		break;
1045 	}
1046 	return 0;
1047 Einval:
1048 	pr_warn(SEL_MOUNT_FAIL_MSG);
1049 	return -EINVAL;
1050 }
1051 
1052 static int selinux_add_mnt_opt(const char *option, const char *val, int len,
1053 			       void **mnt_opts)
1054 {
1055 	int token = Opt_error;
1056 	int rc, i;
1057 
1058 	for (i = 0; i < ARRAY_SIZE(tokens); i++) {
1059 		if (strcmp(option, tokens[i].name) == 0) {
1060 			token = tokens[i].opt;
1061 			break;
1062 		}
1063 	}
1064 
1065 	if (token == Opt_error)
1066 		return -EINVAL;
1067 
1068 	if (token != Opt_seclabel)
1069 		val = kmemdup_nul(val, len, GFP_KERNEL);
1070 	rc = selinux_add_opt(token, val, mnt_opts);
1071 	if (unlikely(rc)) {
1072 		kfree(val);
1073 		if (*mnt_opts) {
1074 			selinux_free_mnt_opts(*mnt_opts);
1075 			*mnt_opts = NULL;
1076 		}
1077 	}
1078 	return rc;
1079 }
1080 
1081 static int show_sid(struct seq_file *m, u32 sid)
1082 {
1083 	char *context = NULL;
1084 	u32 len;
1085 	int rc;
1086 
1087 	rc = security_sid_to_context(&selinux_state, sid,
1088 					     &context, &len);
1089 	if (!rc) {
1090 		bool has_comma = context && strchr(context, ',');
1091 
1092 		if (has_comma)
1093 			seq_putc(m, '\"');
1094 		seq_escape(m, context, "\"\n\\");
1095 		if (has_comma)
1096 			seq_putc(m, '\"');
1097 	}
1098 	kfree(context);
1099 	return rc;
1100 }
1101 
1102 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1103 {
1104 	struct superblock_security_struct *sbsec = sb->s_security;
1105 	int rc;
1106 
1107 	if (!(sbsec->flags & SE_SBINITIALIZED))
1108 		return 0;
1109 
1110 	if (!selinux_state.initialized)
1111 		return 0;
1112 
1113 	if (sbsec->flags & FSCONTEXT_MNT) {
1114 		seq_putc(m, ',');
1115 		seq_puts(m, FSCONTEXT_STR);
1116 		rc = show_sid(m, sbsec->sid);
1117 		if (rc)
1118 			return rc;
1119 	}
1120 	if (sbsec->flags & CONTEXT_MNT) {
1121 		seq_putc(m, ',');
1122 		seq_puts(m, CONTEXT_STR);
1123 		rc = show_sid(m, sbsec->mntpoint_sid);
1124 		if (rc)
1125 			return rc;
1126 	}
1127 	if (sbsec->flags & DEFCONTEXT_MNT) {
1128 		seq_putc(m, ',');
1129 		seq_puts(m, DEFCONTEXT_STR);
1130 		rc = show_sid(m, sbsec->def_sid);
1131 		if (rc)
1132 			return rc;
1133 	}
1134 	if (sbsec->flags & ROOTCONTEXT_MNT) {
1135 		struct dentry *root = sbsec->sb->s_root;
1136 		struct inode_security_struct *isec = backing_inode_security(root);
1137 		seq_putc(m, ',');
1138 		seq_puts(m, ROOTCONTEXT_STR);
1139 		rc = show_sid(m, isec->sid);
1140 		if (rc)
1141 			return rc;
1142 	}
1143 	if (sbsec->flags & SBLABEL_MNT) {
1144 		seq_putc(m, ',');
1145 		seq_puts(m, LABELSUPP_STR);
1146 	}
1147 	return 0;
1148 }
1149 
1150 static inline u16 inode_mode_to_security_class(umode_t mode)
1151 {
1152 	switch (mode & S_IFMT) {
1153 	case S_IFSOCK:
1154 		return SECCLASS_SOCK_FILE;
1155 	case S_IFLNK:
1156 		return SECCLASS_LNK_FILE;
1157 	case S_IFREG:
1158 		return SECCLASS_FILE;
1159 	case S_IFBLK:
1160 		return SECCLASS_BLK_FILE;
1161 	case S_IFDIR:
1162 		return SECCLASS_DIR;
1163 	case S_IFCHR:
1164 		return SECCLASS_CHR_FILE;
1165 	case S_IFIFO:
1166 		return SECCLASS_FIFO_FILE;
1167 
1168 	}
1169 
1170 	return SECCLASS_FILE;
1171 }
1172 
1173 static inline int default_protocol_stream(int protocol)
1174 {
1175 	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1176 }
1177 
1178 static inline int default_protocol_dgram(int protocol)
1179 {
1180 	return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1181 }
1182 
1183 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1184 {
1185 	int extsockclass = selinux_policycap_extsockclass();
1186 
1187 	switch (family) {
1188 	case PF_UNIX:
1189 		switch (type) {
1190 		case SOCK_STREAM:
1191 		case SOCK_SEQPACKET:
1192 			return SECCLASS_UNIX_STREAM_SOCKET;
1193 		case SOCK_DGRAM:
1194 		case SOCK_RAW:
1195 			return SECCLASS_UNIX_DGRAM_SOCKET;
1196 		}
1197 		break;
1198 	case PF_INET:
1199 	case PF_INET6:
1200 		switch (type) {
1201 		case SOCK_STREAM:
1202 		case SOCK_SEQPACKET:
1203 			if (default_protocol_stream(protocol))
1204 				return SECCLASS_TCP_SOCKET;
1205 			else if (extsockclass && protocol == IPPROTO_SCTP)
1206 				return SECCLASS_SCTP_SOCKET;
1207 			else
1208 				return SECCLASS_RAWIP_SOCKET;
1209 		case SOCK_DGRAM:
1210 			if (default_protocol_dgram(protocol))
1211 				return SECCLASS_UDP_SOCKET;
1212 			else if (extsockclass && (protocol == IPPROTO_ICMP ||
1213 						  protocol == IPPROTO_ICMPV6))
1214 				return SECCLASS_ICMP_SOCKET;
1215 			else
1216 				return SECCLASS_RAWIP_SOCKET;
1217 		case SOCK_DCCP:
1218 			return SECCLASS_DCCP_SOCKET;
1219 		default:
1220 			return SECCLASS_RAWIP_SOCKET;
1221 		}
1222 		break;
1223 	case PF_NETLINK:
1224 		switch (protocol) {
1225 		case NETLINK_ROUTE:
1226 			return SECCLASS_NETLINK_ROUTE_SOCKET;
1227 		case NETLINK_SOCK_DIAG:
1228 			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1229 		case NETLINK_NFLOG:
1230 			return SECCLASS_NETLINK_NFLOG_SOCKET;
1231 		case NETLINK_XFRM:
1232 			return SECCLASS_NETLINK_XFRM_SOCKET;
1233 		case NETLINK_SELINUX:
1234 			return SECCLASS_NETLINK_SELINUX_SOCKET;
1235 		case NETLINK_ISCSI:
1236 			return SECCLASS_NETLINK_ISCSI_SOCKET;
1237 		case NETLINK_AUDIT:
1238 			return SECCLASS_NETLINK_AUDIT_SOCKET;
1239 		case NETLINK_FIB_LOOKUP:
1240 			return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1241 		case NETLINK_CONNECTOR:
1242 			return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1243 		case NETLINK_NETFILTER:
1244 			return SECCLASS_NETLINK_NETFILTER_SOCKET;
1245 		case NETLINK_DNRTMSG:
1246 			return SECCLASS_NETLINK_DNRT_SOCKET;
1247 		case NETLINK_KOBJECT_UEVENT:
1248 			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1249 		case NETLINK_GENERIC:
1250 			return SECCLASS_NETLINK_GENERIC_SOCKET;
1251 		case NETLINK_SCSITRANSPORT:
1252 			return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1253 		case NETLINK_RDMA:
1254 			return SECCLASS_NETLINK_RDMA_SOCKET;
1255 		case NETLINK_CRYPTO:
1256 			return SECCLASS_NETLINK_CRYPTO_SOCKET;
1257 		default:
1258 			return SECCLASS_NETLINK_SOCKET;
1259 		}
1260 	case PF_PACKET:
1261 		return SECCLASS_PACKET_SOCKET;
1262 	case PF_KEY:
1263 		return SECCLASS_KEY_SOCKET;
1264 	case PF_APPLETALK:
1265 		return SECCLASS_APPLETALK_SOCKET;
1266 	}
1267 
1268 	if (extsockclass) {
1269 		switch (family) {
1270 		case PF_AX25:
1271 			return SECCLASS_AX25_SOCKET;
1272 		case PF_IPX:
1273 			return SECCLASS_IPX_SOCKET;
1274 		case PF_NETROM:
1275 			return SECCLASS_NETROM_SOCKET;
1276 		case PF_ATMPVC:
1277 			return SECCLASS_ATMPVC_SOCKET;
1278 		case PF_X25:
1279 			return SECCLASS_X25_SOCKET;
1280 		case PF_ROSE:
1281 			return SECCLASS_ROSE_SOCKET;
1282 		case PF_DECnet:
1283 			return SECCLASS_DECNET_SOCKET;
1284 		case PF_ATMSVC:
1285 			return SECCLASS_ATMSVC_SOCKET;
1286 		case PF_RDS:
1287 			return SECCLASS_RDS_SOCKET;
1288 		case PF_IRDA:
1289 			return SECCLASS_IRDA_SOCKET;
1290 		case PF_PPPOX:
1291 			return SECCLASS_PPPOX_SOCKET;
1292 		case PF_LLC:
1293 			return SECCLASS_LLC_SOCKET;
1294 		case PF_CAN:
1295 			return SECCLASS_CAN_SOCKET;
1296 		case PF_TIPC:
1297 			return SECCLASS_TIPC_SOCKET;
1298 		case PF_BLUETOOTH:
1299 			return SECCLASS_BLUETOOTH_SOCKET;
1300 		case PF_IUCV:
1301 			return SECCLASS_IUCV_SOCKET;
1302 		case PF_RXRPC:
1303 			return SECCLASS_RXRPC_SOCKET;
1304 		case PF_ISDN:
1305 			return SECCLASS_ISDN_SOCKET;
1306 		case PF_PHONET:
1307 			return SECCLASS_PHONET_SOCKET;
1308 		case PF_IEEE802154:
1309 			return SECCLASS_IEEE802154_SOCKET;
1310 		case PF_CAIF:
1311 			return SECCLASS_CAIF_SOCKET;
1312 		case PF_ALG:
1313 			return SECCLASS_ALG_SOCKET;
1314 		case PF_NFC:
1315 			return SECCLASS_NFC_SOCKET;
1316 		case PF_VSOCK:
1317 			return SECCLASS_VSOCK_SOCKET;
1318 		case PF_KCM:
1319 			return SECCLASS_KCM_SOCKET;
1320 		case PF_QIPCRTR:
1321 			return SECCLASS_QIPCRTR_SOCKET;
1322 		case PF_SMC:
1323 			return SECCLASS_SMC_SOCKET;
1324 		case PF_XDP:
1325 			return SECCLASS_XDP_SOCKET;
1326 #if PF_MAX > 45
1327 #error New address family defined, please update this function.
1328 #endif
1329 		}
1330 	}
1331 
1332 	return SECCLASS_SOCKET;
1333 }
1334 
1335 static int selinux_genfs_get_sid(struct dentry *dentry,
1336 				 u16 tclass,
1337 				 u16 flags,
1338 				 u32 *sid)
1339 {
1340 	int rc;
1341 	struct super_block *sb = dentry->d_sb;
1342 	char *buffer, *path;
1343 
1344 	buffer = (char *)__get_free_page(GFP_KERNEL);
1345 	if (!buffer)
1346 		return -ENOMEM;
1347 
1348 	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1349 	if (IS_ERR(path))
1350 		rc = PTR_ERR(path);
1351 	else {
1352 		if (flags & SE_SBPROC) {
1353 			/* each process gets a /proc/PID/ entry. Strip off the
1354 			 * PID part to get a valid selinux labeling.
1355 			 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1356 			while (path[1] >= '0' && path[1] <= '9') {
1357 				path[1] = '/';
1358 				path++;
1359 			}
1360 		}
1361 		rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1362 					path, tclass, sid);
1363 		if (rc == -ENOENT) {
1364 			/* No match in policy, mark as unlabeled. */
1365 			*sid = SECINITSID_UNLABELED;
1366 			rc = 0;
1367 		}
1368 	}
1369 	free_page((unsigned long)buffer);
1370 	return rc;
1371 }
1372 
1373 /* The inode's security attributes must be initialized before first use. */
1374 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1375 {
1376 	struct superblock_security_struct *sbsec = NULL;
1377 	struct inode_security_struct *isec = inode->i_security;
1378 	u32 task_sid, sid = 0;
1379 	u16 sclass;
1380 	struct dentry *dentry;
1381 #define INITCONTEXTLEN 255
1382 	char *context = NULL;
1383 	unsigned len = 0;
1384 	int rc = 0;
1385 
1386 	if (isec->initialized == LABEL_INITIALIZED)
1387 		return 0;
1388 
1389 	spin_lock(&isec->lock);
1390 	if (isec->initialized == LABEL_INITIALIZED)
1391 		goto out_unlock;
1392 
1393 	if (isec->sclass == SECCLASS_FILE)
1394 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
1395 
1396 	sbsec = inode->i_sb->s_security;
1397 	if (!(sbsec->flags & SE_SBINITIALIZED)) {
1398 		/* Defer initialization until selinux_complete_init,
1399 		   after the initial policy is loaded and the security
1400 		   server is ready to handle calls. */
1401 		spin_lock(&sbsec->isec_lock);
1402 		if (list_empty(&isec->list))
1403 			list_add(&isec->list, &sbsec->isec_head);
1404 		spin_unlock(&sbsec->isec_lock);
1405 		goto out_unlock;
1406 	}
1407 
1408 	sclass = isec->sclass;
1409 	task_sid = isec->task_sid;
1410 	sid = isec->sid;
1411 	isec->initialized = LABEL_PENDING;
1412 	spin_unlock(&isec->lock);
1413 
1414 	switch (sbsec->behavior) {
1415 	case SECURITY_FS_USE_NATIVE:
1416 		break;
1417 	case SECURITY_FS_USE_XATTR:
1418 		if (!(inode->i_opflags & IOP_XATTR)) {
1419 			sid = sbsec->def_sid;
1420 			break;
1421 		}
1422 		/* Need a dentry, since the xattr API requires one.
1423 		   Life would be simpler if we could just pass the inode. */
1424 		if (opt_dentry) {
1425 			/* Called from d_instantiate or d_splice_alias. */
1426 			dentry = dget(opt_dentry);
1427 		} else {
1428 			/*
1429 			 * Called from selinux_complete_init, try to find a dentry.
1430 			 * Some filesystems really want a connected one, so try
1431 			 * that first.  We could split SECURITY_FS_USE_XATTR in
1432 			 * two, depending upon that...
1433 			 */
1434 			dentry = d_find_alias(inode);
1435 			if (!dentry)
1436 				dentry = d_find_any_alias(inode);
1437 		}
1438 		if (!dentry) {
1439 			/*
1440 			 * this is can be hit on boot when a file is accessed
1441 			 * before the policy is loaded.  When we load policy we
1442 			 * may find inodes that have no dentry on the
1443 			 * sbsec->isec_head list.  No reason to complain as these
1444 			 * will get fixed up the next time we go through
1445 			 * inode_doinit with a dentry, before these inodes could
1446 			 * be used again by userspace.
1447 			 */
1448 			goto out;
1449 		}
1450 
1451 		len = INITCONTEXTLEN;
1452 		context = kmalloc(len+1, GFP_NOFS);
1453 		if (!context) {
1454 			rc = -ENOMEM;
1455 			dput(dentry);
1456 			goto out;
1457 		}
1458 		context[len] = '\0';
1459 		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1460 		if (rc == -ERANGE) {
1461 			kfree(context);
1462 
1463 			/* Need a larger buffer.  Query for the right size. */
1464 			rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1465 			if (rc < 0) {
1466 				dput(dentry);
1467 				goto out;
1468 			}
1469 			len = rc;
1470 			context = kmalloc(len+1, GFP_NOFS);
1471 			if (!context) {
1472 				rc = -ENOMEM;
1473 				dput(dentry);
1474 				goto out;
1475 			}
1476 			context[len] = '\0';
1477 			rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1478 		}
1479 		dput(dentry);
1480 		if (rc < 0) {
1481 			if (rc != -ENODATA) {
1482 				pr_warn("SELinux: %s:  getxattr returned "
1483 				       "%d for dev=%s ino=%ld\n", __func__,
1484 				       -rc, inode->i_sb->s_id, inode->i_ino);
1485 				kfree(context);
1486 				goto out;
1487 			}
1488 			/* Map ENODATA to the default file SID */
1489 			sid = sbsec->def_sid;
1490 			rc = 0;
1491 		} else {
1492 			rc = security_context_to_sid_default(&selinux_state,
1493 							     context, rc, &sid,
1494 							     sbsec->def_sid,
1495 							     GFP_NOFS);
1496 			if (rc) {
1497 				char *dev = inode->i_sb->s_id;
1498 				unsigned long ino = inode->i_ino;
1499 
1500 				if (rc == -EINVAL) {
1501 					if (printk_ratelimit())
1502 						pr_notice("SELinux: inode=%lu on dev=%s was found to have an invalid "
1503 							"context=%s.  This indicates you may need to relabel the inode or the "
1504 							"filesystem in question.\n", ino, dev, context);
1505 				} else {
1506 					pr_warn("SELinux: %s:  context_to_sid(%s) "
1507 					       "returned %d for dev=%s ino=%ld\n",
1508 					       __func__, context, -rc, dev, ino);
1509 				}
1510 				kfree(context);
1511 				/* Leave with the unlabeled SID */
1512 				rc = 0;
1513 				break;
1514 			}
1515 		}
1516 		kfree(context);
1517 		break;
1518 	case SECURITY_FS_USE_TASK:
1519 		sid = task_sid;
1520 		break;
1521 	case SECURITY_FS_USE_TRANS:
1522 		/* Default to the fs SID. */
1523 		sid = sbsec->sid;
1524 
1525 		/* Try to obtain a transition SID. */
1526 		rc = security_transition_sid(&selinux_state, task_sid, sid,
1527 					     sclass, NULL, &sid);
1528 		if (rc)
1529 			goto out;
1530 		break;
1531 	case SECURITY_FS_USE_MNTPOINT:
1532 		sid = sbsec->mntpoint_sid;
1533 		break;
1534 	default:
1535 		/* Default to the fs superblock SID. */
1536 		sid = sbsec->sid;
1537 
1538 		if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1539 			/* We must have a dentry to determine the label on
1540 			 * procfs inodes */
1541 			if (opt_dentry) {
1542 				/* Called from d_instantiate or
1543 				 * d_splice_alias. */
1544 				dentry = dget(opt_dentry);
1545 			} else {
1546 				/* Called from selinux_complete_init, try to
1547 				 * find a dentry.  Some filesystems really want
1548 				 * a connected one, so try that first.
1549 				 */
1550 				dentry = d_find_alias(inode);
1551 				if (!dentry)
1552 					dentry = d_find_any_alias(inode);
1553 			}
1554 			/*
1555 			 * This can be hit on boot when a file is accessed
1556 			 * before the policy is loaded.  When we load policy we
1557 			 * may find inodes that have no dentry on the
1558 			 * sbsec->isec_head list.  No reason to complain as
1559 			 * these will get fixed up the next time we go through
1560 			 * inode_doinit() with a dentry, before these inodes
1561 			 * could be used again by userspace.
1562 			 */
1563 			if (!dentry)
1564 				goto out;
1565 			rc = selinux_genfs_get_sid(dentry, sclass,
1566 						   sbsec->flags, &sid);
1567 			dput(dentry);
1568 			if (rc)
1569 				goto out;
1570 		}
1571 		break;
1572 	}
1573 
1574 out:
1575 	spin_lock(&isec->lock);
1576 	if (isec->initialized == LABEL_PENDING) {
1577 		if (!sid || rc) {
1578 			isec->initialized = LABEL_INVALID;
1579 			goto out_unlock;
1580 		}
1581 
1582 		isec->initialized = LABEL_INITIALIZED;
1583 		isec->sid = sid;
1584 	}
1585 
1586 out_unlock:
1587 	spin_unlock(&isec->lock);
1588 	return rc;
1589 }
1590 
1591 /* Convert a Linux signal to an access vector. */
1592 static inline u32 signal_to_av(int sig)
1593 {
1594 	u32 perm = 0;
1595 
1596 	switch (sig) {
1597 	case SIGCHLD:
1598 		/* Commonly granted from child to parent. */
1599 		perm = PROCESS__SIGCHLD;
1600 		break;
1601 	case SIGKILL:
1602 		/* Cannot be caught or ignored */
1603 		perm = PROCESS__SIGKILL;
1604 		break;
1605 	case SIGSTOP:
1606 		/* Cannot be caught or ignored */
1607 		perm = PROCESS__SIGSTOP;
1608 		break;
1609 	default:
1610 		/* All other signals. */
1611 		perm = PROCESS__SIGNAL;
1612 		break;
1613 	}
1614 
1615 	return perm;
1616 }
1617 
1618 #if CAP_LAST_CAP > 63
1619 #error Fix SELinux to handle capabilities > 63.
1620 #endif
1621 
1622 /* Check whether a task is allowed to use a capability. */
1623 static int cred_has_capability(const struct cred *cred,
1624 			       int cap, int audit, bool initns)
1625 {
1626 	struct common_audit_data ad;
1627 	struct av_decision avd;
1628 	u16 sclass;
1629 	u32 sid = cred_sid(cred);
1630 	u32 av = CAP_TO_MASK(cap);
1631 	int rc;
1632 
1633 	ad.type = LSM_AUDIT_DATA_CAP;
1634 	ad.u.cap = cap;
1635 
1636 	switch (CAP_TO_INDEX(cap)) {
1637 	case 0:
1638 		sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1639 		break;
1640 	case 1:
1641 		sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1642 		break;
1643 	default:
1644 		pr_err("SELinux:  out of range capability %d\n", cap);
1645 		BUG();
1646 		return -EINVAL;
1647 	}
1648 
1649 	rc = avc_has_perm_noaudit(&selinux_state,
1650 				  sid, sid, sclass, av, 0, &avd);
1651 	if (audit == SECURITY_CAP_AUDIT) {
1652 		int rc2 = avc_audit(&selinux_state,
1653 				    sid, sid, sclass, av, &avd, rc, &ad, 0);
1654 		if (rc2)
1655 			return rc2;
1656 	}
1657 	return rc;
1658 }
1659 
1660 /* Check whether a task has a particular permission to an inode.
1661    The 'adp' parameter is optional and allows other audit
1662    data to be passed (e.g. the dentry). */
1663 static int inode_has_perm(const struct cred *cred,
1664 			  struct inode *inode,
1665 			  u32 perms,
1666 			  struct common_audit_data *adp)
1667 {
1668 	struct inode_security_struct *isec;
1669 	u32 sid;
1670 
1671 	validate_creds(cred);
1672 
1673 	if (unlikely(IS_PRIVATE(inode)))
1674 		return 0;
1675 
1676 	sid = cred_sid(cred);
1677 	isec = inode->i_security;
1678 
1679 	return avc_has_perm(&selinux_state,
1680 			    sid, isec->sid, isec->sclass, perms, adp);
1681 }
1682 
1683 /* Same as inode_has_perm, but pass explicit audit data containing
1684    the dentry to help the auditing code to more easily generate the
1685    pathname if needed. */
1686 static inline int dentry_has_perm(const struct cred *cred,
1687 				  struct dentry *dentry,
1688 				  u32 av)
1689 {
1690 	struct inode *inode = d_backing_inode(dentry);
1691 	struct common_audit_data ad;
1692 
1693 	ad.type = LSM_AUDIT_DATA_DENTRY;
1694 	ad.u.dentry = dentry;
1695 	__inode_security_revalidate(inode, dentry, true);
1696 	return inode_has_perm(cred, inode, av, &ad);
1697 }
1698 
1699 /* Same as inode_has_perm, but pass explicit audit data containing
1700    the path to help the auditing code to more easily generate the
1701    pathname if needed. */
1702 static inline int path_has_perm(const struct cred *cred,
1703 				const struct path *path,
1704 				u32 av)
1705 {
1706 	struct inode *inode = d_backing_inode(path->dentry);
1707 	struct common_audit_data ad;
1708 
1709 	ad.type = LSM_AUDIT_DATA_PATH;
1710 	ad.u.path = *path;
1711 	__inode_security_revalidate(inode, path->dentry, true);
1712 	return inode_has_perm(cred, inode, av, &ad);
1713 }
1714 
1715 /* Same as path_has_perm, but uses the inode from the file struct. */
1716 static inline int file_path_has_perm(const struct cred *cred,
1717 				     struct file *file,
1718 				     u32 av)
1719 {
1720 	struct common_audit_data ad;
1721 
1722 	ad.type = LSM_AUDIT_DATA_FILE;
1723 	ad.u.file = file;
1724 	return inode_has_perm(cred, file_inode(file), av, &ad);
1725 }
1726 
1727 #ifdef CONFIG_BPF_SYSCALL
1728 static int bpf_fd_pass(struct file *file, u32 sid);
1729 #endif
1730 
1731 /* Check whether a task can use an open file descriptor to
1732    access an inode in a given way.  Check access to the
1733    descriptor itself, and then use dentry_has_perm to
1734    check a particular permission to the file.
1735    Access to the descriptor is implicitly granted if it
1736    has the same SID as the process.  If av is zero, then
1737    access to the file is not checked, e.g. for cases
1738    where only the descriptor is affected like seek. */
1739 static int file_has_perm(const struct cred *cred,
1740 			 struct file *file,
1741 			 u32 av)
1742 {
1743 	struct file_security_struct *fsec = file->f_security;
1744 	struct inode *inode = file_inode(file);
1745 	struct common_audit_data ad;
1746 	u32 sid = cred_sid(cred);
1747 	int rc;
1748 
1749 	ad.type = LSM_AUDIT_DATA_FILE;
1750 	ad.u.file = file;
1751 
1752 	if (sid != fsec->sid) {
1753 		rc = avc_has_perm(&selinux_state,
1754 				  sid, fsec->sid,
1755 				  SECCLASS_FD,
1756 				  FD__USE,
1757 				  &ad);
1758 		if (rc)
1759 			goto out;
1760 	}
1761 
1762 #ifdef CONFIG_BPF_SYSCALL
1763 	rc = bpf_fd_pass(file, cred_sid(cred));
1764 	if (rc)
1765 		return rc;
1766 #endif
1767 
1768 	/* av is zero if only checking access to the descriptor. */
1769 	rc = 0;
1770 	if (av)
1771 		rc = inode_has_perm(cred, inode, av, &ad);
1772 
1773 out:
1774 	return rc;
1775 }
1776 
1777 /*
1778  * Determine the label for an inode that might be unioned.
1779  */
1780 static int
1781 selinux_determine_inode_label(const struct task_security_struct *tsec,
1782 				 struct inode *dir,
1783 				 const struct qstr *name, u16 tclass,
1784 				 u32 *_new_isid)
1785 {
1786 	const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1787 
1788 	if ((sbsec->flags & SE_SBINITIALIZED) &&
1789 	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1790 		*_new_isid = sbsec->mntpoint_sid;
1791 	} else if ((sbsec->flags & SBLABEL_MNT) &&
1792 		   tsec->create_sid) {
1793 		*_new_isid = tsec->create_sid;
1794 	} else {
1795 		const struct inode_security_struct *dsec = inode_security(dir);
1796 		return security_transition_sid(&selinux_state, tsec->sid,
1797 					       dsec->sid, tclass,
1798 					       name, _new_isid);
1799 	}
1800 
1801 	return 0;
1802 }
1803 
1804 /* Check whether a task can create a file. */
1805 static int may_create(struct inode *dir,
1806 		      struct dentry *dentry,
1807 		      u16 tclass)
1808 {
1809 	const struct task_security_struct *tsec = current_security();
1810 	struct inode_security_struct *dsec;
1811 	struct superblock_security_struct *sbsec;
1812 	u32 sid, newsid;
1813 	struct common_audit_data ad;
1814 	int rc;
1815 
1816 	dsec = inode_security(dir);
1817 	sbsec = dir->i_sb->s_security;
1818 
1819 	sid = tsec->sid;
1820 
1821 	ad.type = LSM_AUDIT_DATA_DENTRY;
1822 	ad.u.dentry = dentry;
1823 
1824 	rc = avc_has_perm(&selinux_state,
1825 			  sid, dsec->sid, SECCLASS_DIR,
1826 			  DIR__ADD_NAME | DIR__SEARCH,
1827 			  &ad);
1828 	if (rc)
1829 		return rc;
1830 
1831 	rc = selinux_determine_inode_label(current_security(), dir,
1832 					   &dentry->d_name, tclass, &newsid);
1833 	if (rc)
1834 		return rc;
1835 
1836 	rc = avc_has_perm(&selinux_state,
1837 			  sid, newsid, tclass, FILE__CREATE, &ad);
1838 	if (rc)
1839 		return rc;
1840 
1841 	return avc_has_perm(&selinux_state,
1842 			    newsid, sbsec->sid,
1843 			    SECCLASS_FILESYSTEM,
1844 			    FILESYSTEM__ASSOCIATE, &ad);
1845 }
1846 
1847 #define MAY_LINK	0
1848 #define MAY_UNLINK	1
1849 #define MAY_RMDIR	2
1850 
1851 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1852 static int may_link(struct inode *dir,
1853 		    struct dentry *dentry,
1854 		    int kind)
1855 
1856 {
1857 	struct inode_security_struct *dsec, *isec;
1858 	struct common_audit_data ad;
1859 	u32 sid = current_sid();
1860 	u32 av;
1861 	int rc;
1862 
1863 	dsec = inode_security(dir);
1864 	isec = backing_inode_security(dentry);
1865 
1866 	ad.type = LSM_AUDIT_DATA_DENTRY;
1867 	ad.u.dentry = dentry;
1868 
1869 	av = DIR__SEARCH;
1870 	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1871 	rc = avc_has_perm(&selinux_state,
1872 			  sid, dsec->sid, SECCLASS_DIR, av, &ad);
1873 	if (rc)
1874 		return rc;
1875 
1876 	switch (kind) {
1877 	case MAY_LINK:
1878 		av = FILE__LINK;
1879 		break;
1880 	case MAY_UNLINK:
1881 		av = FILE__UNLINK;
1882 		break;
1883 	case MAY_RMDIR:
1884 		av = DIR__RMDIR;
1885 		break;
1886 	default:
1887 		pr_warn("SELinux: %s:  unrecognized kind %d\n",
1888 			__func__, kind);
1889 		return 0;
1890 	}
1891 
1892 	rc = avc_has_perm(&selinux_state,
1893 			  sid, isec->sid, isec->sclass, av, &ad);
1894 	return rc;
1895 }
1896 
1897 static inline int may_rename(struct inode *old_dir,
1898 			     struct dentry *old_dentry,
1899 			     struct inode *new_dir,
1900 			     struct dentry *new_dentry)
1901 {
1902 	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1903 	struct common_audit_data ad;
1904 	u32 sid = current_sid();
1905 	u32 av;
1906 	int old_is_dir, new_is_dir;
1907 	int rc;
1908 
1909 	old_dsec = inode_security(old_dir);
1910 	old_isec = backing_inode_security(old_dentry);
1911 	old_is_dir = d_is_dir(old_dentry);
1912 	new_dsec = inode_security(new_dir);
1913 
1914 	ad.type = LSM_AUDIT_DATA_DENTRY;
1915 
1916 	ad.u.dentry = old_dentry;
1917 	rc = avc_has_perm(&selinux_state,
1918 			  sid, old_dsec->sid, SECCLASS_DIR,
1919 			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1920 	if (rc)
1921 		return rc;
1922 	rc = avc_has_perm(&selinux_state,
1923 			  sid, old_isec->sid,
1924 			  old_isec->sclass, FILE__RENAME, &ad);
1925 	if (rc)
1926 		return rc;
1927 	if (old_is_dir && new_dir != old_dir) {
1928 		rc = avc_has_perm(&selinux_state,
1929 				  sid, old_isec->sid,
1930 				  old_isec->sclass, DIR__REPARENT, &ad);
1931 		if (rc)
1932 			return rc;
1933 	}
1934 
1935 	ad.u.dentry = new_dentry;
1936 	av = DIR__ADD_NAME | DIR__SEARCH;
1937 	if (d_is_positive(new_dentry))
1938 		av |= DIR__REMOVE_NAME;
1939 	rc = avc_has_perm(&selinux_state,
1940 			  sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1941 	if (rc)
1942 		return rc;
1943 	if (d_is_positive(new_dentry)) {
1944 		new_isec = backing_inode_security(new_dentry);
1945 		new_is_dir = d_is_dir(new_dentry);
1946 		rc = avc_has_perm(&selinux_state,
1947 				  sid, new_isec->sid,
1948 				  new_isec->sclass,
1949 				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1950 		if (rc)
1951 			return rc;
1952 	}
1953 
1954 	return 0;
1955 }
1956 
1957 /* Check whether a task can perform a filesystem operation. */
1958 static int superblock_has_perm(const struct cred *cred,
1959 			       struct super_block *sb,
1960 			       u32 perms,
1961 			       struct common_audit_data *ad)
1962 {
1963 	struct superblock_security_struct *sbsec;
1964 	u32 sid = cred_sid(cred);
1965 
1966 	sbsec = sb->s_security;
1967 	return avc_has_perm(&selinux_state,
1968 			    sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1969 }
1970 
1971 /* Convert a Linux mode and permission mask to an access vector. */
1972 static inline u32 file_mask_to_av(int mode, int mask)
1973 {
1974 	u32 av = 0;
1975 
1976 	if (!S_ISDIR(mode)) {
1977 		if (mask & MAY_EXEC)
1978 			av |= FILE__EXECUTE;
1979 		if (mask & MAY_READ)
1980 			av |= FILE__READ;
1981 
1982 		if (mask & MAY_APPEND)
1983 			av |= FILE__APPEND;
1984 		else if (mask & MAY_WRITE)
1985 			av |= FILE__WRITE;
1986 
1987 	} else {
1988 		if (mask & MAY_EXEC)
1989 			av |= DIR__SEARCH;
1990 		if (mask & MAY_WRITE)
1991 			av |= DIR__WRITE;
1992 		if (mask & MAY_READ)
1993 			av |= DIR__READ;
1994 	}
1995 
1996 	return av;
1997 }
1998 
1999 /* Convert a Linux file to an access vector. */
2000 static inline u32 file_to_av(struct file *file)
2001 {
2002 	u32 av = 0;
2003 
2004 	if (file->f_mode & FMODE_READ)
2005 		av |= FILE__READ;
2006 	if (file->f_mode & FMODE_WRITE) {
2007 		if (file->f_flags & O_APPEND)
2008 			av |= FILE__APPEND;
2009 		else
2010 			av |= FILE__WRITE;
2011 	}
2012 	if (!av) {
2013 		/*
2014 		 * Special file opened with flags 3 for ioctl-only use.
2015 		 */
2016 		av = FILE__IOCTL;
2017 	}
2018 
2019 	return av;
2020 }
2021 
2022 /*
2023  * Convert a file to an access vector and include the correct open
2024  * open permission.
2025  */
2026 static inline u32 open_file_to_av(struct file *file)
2027 {
2028 	u32 av = file_to_av(file);
2029 	struct inode *inode = file_inode(file);
2030 
2031 	if (selinux_policycap_openperm() &&
2032 	    inode->i_sb->s_magic != SOCKFS_MAGIC)
2033 		av |= FILE__OPEN;
2034 
2035 	return av;
2036 }
2037 
2038 /* Hook functions begin here. */
2039 
2040 static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2041 {
2042 	u32 mysid = current_sid();
2043 	u32 mgrsid = task_sid(mgr);
2044 
2045 	return avc_has_perm(&selinux_state,
2046 			    mysid, mgrsid, SECCLASS_BINDER,
2047 			    BINDER__SET_CONTEXT_MGR, NULL);
2048 }
2049 
2050 static int selinux_binder_transaction(struct task_struct *from,
2051 				      struct task_struct *to)
2052 {
2053 	u32 mysid = current_sid();
2054 	u32 fromsid = task_sid(from);
2055 	u32 tosid = task_sid(to);
2056 	int rc;
2057 
2058 	if (mysid != fromsid) {
2059 		rc = avc_has_perm(&selinux_state,
2060 				  mysid, fromsid, SECCLASS_BINDER,
2061 				  BINDER__IMPERSONATE, NULL);
2062 		if (rc)
2063 			return rc;
2064 	}
2065 
2066 	return avc_has_perm(&selinux_state,
2067 			    fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2068 			    NULL);
2069 }
2070 
2071 static int selinux_binder_transfer_binder(struct task_struct *from,
2072 					  struct task_struct *to)
2073 {
2074 	u32 fromsid = task_sid(from);
2075 	u32 tosid = task_sid(to);
2076 
2077 	return avc_has_perm(&selinux_state,
2078 			    fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2079 			    NULL);
2080 }
2081 
2082 static int selinux_binder_transfer_file(struct task_struct *from,
2083 					struct task_struct *to,
2084 					struct file *file)
2085 {
2086 	u32 sid = task_sid(to);
2087 	struct file_security_struct *fsec = file->f_security;
2088 	struct dentry *dentry = file->f_path.dentry;
2089 	struct inode_security_struct *isec;
2090 	struct common_audit_data ad;
2091 	int rc;
2092 
2093 	ad.type = LSM_AUDIT_DATA_PATH;
2094 	ad.u.path = file->f_path;
2095 
2096 	if (sid != fsec->sid) {
2097 		rc = avc_has_perm(&selinux_state,
2098 				  sid, fsec->sid,
2099 				  SECCLASS_FD,
2100 				  FD__USE,
2101 				  &ad);
2102 		if (rc)
2103 			return rc;
2104 	}
2105 
2106 #ifdef CONFIG_BPF_SYSCALL
2107 	rc = bpf_fd_pass(file, sid);
2108 	if (rc)
2109 		return rc;
2110 #endif
2111 
2112 	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2113 		return 0;
2114 
2115 	isec = backing_inode_security(dentry);
2116 	return avc_has_perm(&selinux_state,
2117 			    sid, isec->sid, isec->sclass, file_to_av(file),
2118 			    &ad);
2119 }
2120 
2121 static int selinux_ptrace_access_check(struct task_struct *child,
2122 				     unsigned int mode)
2123 {
2124 	u32 sid = current_sid();
2125 	u32 csid = task_sid(child);
2126 
2127 	if (mode & PTRACE_MODE_READ)
2128 		return avc_has_perm(&selinux_state,
2129 				    sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2130 
2131 	return avc_has_perm(&selinux_state,
2132 			    sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2133 }
2134 
2135 static int selinux_ptrace_traceme(struct task_struct *parent)
2136 {
2137 	return avc_has_perm(&selinux_state,
2138 			    task_sid(parent), current_sid(), SECCLASS_PROCESS,
2139 			    PROCESS__PTRACE, NULL);
2140 }
2141 
2142 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2143 			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
2144 {
2145 	return avc_has_perm(&selinux_state,
2146 			    current_sid(), task_sid(target), SECCLASS_PROCESS,
2147 			    PROCESS__GETCAP, NULL);
2148 }
2149 
2150 static int selinux_capset(struct cred *new, const struct cred *old,
2151 			  const kernel_cap_t *effective,
2152 			  const kernel_cap_t *inheritable,
2153 			  const kernel_cap_t *permitted)
2154 {
2155 	return avc_has_perm(&selinux_state,
2156 			    cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2157 			    PROCESS__SETCAP, NULL);
2158 }
2159 
2160 /*
2161  * (This comment used to live with the selinux_task_setuid hook,
2162  * which was removed).
2163  *
2164  * Since setuid only affects the current process, and since the SELinux
2165  * controls are not based on the Linux identity attributes, SELinux does not
2166  * need to control this operation.  However, SELinux does control the use of
2167  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2168  */
2169 
2170 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2171 			   int cap, int audit)
2172 {
2173 	return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
2174 }
2175 
2176 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2177 {
2178 	const struct cred *cred = current_cred();
2179 	int rc = 0;
2180 
2181 	if (!sb)
2182 		return 0;
2183 
2184 	switch (cmds) {
2185 	case Q_SYNC:
2186 	case Q_QUOTAON:
2187 	case Q_QUOTAOFF:
2188 	case Q_SETINFO:
2189 	case Q_SETQUOTA:
2190 		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2191 		break;
2192 	case Q_GETFMT:
2193 	case Q_GETINFO:
2194 	case Q_GETQUOTA:
2195 		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2196 		break;
2197 	default:
2198 		rc = 0;  /* let the kernel handle invalid cmds */
2199 		break;
2200 	}
2201 	return rc;
2202 }
2203 
2204 static int selinux_quota_on(struct dentry *dentry)
2205 {
2206 	const struct cred *cred = current_cred();
2207 
2208 	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2209 }
2210 
2211 static int selinux_syslog(int type)
2212 {
2213 	switch (type) {
2214 	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
2215 	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2216 		return avc_has_perm(&selinux_state,
2217 				    current_sid(), SECINITSID_KERNEL,
2218 				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2219 	case SYSLOG_ACTION_CONSOLE_OFF:	/* Disable logging to console */
2220 	case SYSLOG_ACTION_CONSOLE_ON:	/* Enable logging to console */
2221 	/* Set level of messages printed to console */
2222 	case SYSLOG_ACTION_CONSOLE_LEVEL:
2223 		return avc_has_perm(&selinux_state,
2224 				    current_sid(), SECINITSID_KERNEL,
2225 				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2226 				    NULL);
2227 	}
2228 	/* All other syslog types */
2229 	return avc_has_perm(&selinux_state,
2230 			    current_sid(), SECINITSID_KERNEL,
2231 			    SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2232 }
2233 
2234 /*
2235  * Check that a process has enough memory to allocate a new virtual
2236  * mapping. 0 means there is enough memory for the allocation to
2237  * succeed and -ENOMEM implies there is not.
2238  *
2239  * Do not audit the selinux permission check, as this is applied to all
2240  * processes that allocate mappings.
2241  */
2242 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2243 {
2244 	int rc, cap_sys_admin = 0;
2245 
2246 	rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2247 				 SECURITY_CAP_NOAUDIT, true);
2248 	if (rc == 0)
2249 		cap_sys_admin = 1;
2250 
2251 	return cap_sys_admin;
2252 }
2253 
2254 /* binprm security operations */
2255 
2256 static u32 ptrace_parent_sid(void)
2257 {
2258 	u32 sid = 0;
2259 	struct task_struct *tracer;
2260 
2261 	rcu_read_lock();
2262 	tracer = ptrace_parent(current);
2263 	if (tracer)
2264 		sid = task_sid(tracer);
2265 	rcu_read_unlock();
2266 
2267 	return sid;
2268 }
2269 
2270 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2271 			    const struct task_security_struct *old_tsec,
2272 			    const struct task_security_struct *new_tsec)
2273 {
2274 	int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2275 	int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2276 	int rc;
2277 	u32 av;
2278 
2279 	if (!nnp && !nosuid)
2280 		return 0; /* neither NNP nor nosuid */
2281 
2282 	if (new_tsec->sid == old_tsec->sid)
2283 		return 0; /* No change in credentials */
2284 
2285 	/*
2286 	 * If the policy enables the nnp_nosuid_transition policy capability,
2287 	 * then we permit transitions under NNP or nosuid if the
2288 	 * policy allows the corresponding permission between
2289 	 * the old and new contexts.
2290 	 */
2291 	if (selinux_policycap_nnp_nosuid_transition()) {
2292 		av = 0;
2293 		if (nnp)
2294 			av |= PROCESS2__NNP_TRANSITION;
2295 		if (nosuid)
2296 			av |= PROCESS2__NOSUID_TRANSITION;
2297 		rc = avc_has_perm(&selinux_state,
2298 				  old_tsec->sid, new_tsec->sid,
2299 				  SECCLASS_PROCESS2, av, NULL);
2300 		if (!rc)
2301 			return 0;
2302 	}
2303 
2304 	/*
2305 	 * We also permit NNP or nosuid transitions to bounded SIDs,
2306 	 * i.e. SIDs that are guaranteed to only be allowed a subset
2307 	 * of the permissions of the current SID.
2308 	 */
2309 	rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2310 					 new_tsec->sid);
2311 	if (!rc)
2312 		return 0;
2313 
2314 	/*
2315 	 * On failure, preserve the errno values for NNP vs nosuid.
2316 	 * NNP:  Operation not permitted for caller.
2317 	 * nosuid:  Permission denied to file.
2318 	 */
2319 	if (nnp)
2320 		return -EPERM;
2321 	return -EACCES;
2322 }
2323 
2324 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2325 {
2326 	const struct task_security_struct *old_tsec;
2327 	struct task_security_struct *new_tsec;
2328 	struct inode_security_struct *isec;
2329 	struct common_audit_data ad;
2330 	struct inode *inode = file_inode(bprm->file);
2331 	int rc;
2332 
2333 	/* SELinux context only depends on initial program or script and not
2334 	 * the script interpreter */
2335 	if (bprm->called_set_creds)
2336 		return 0;
2337 
2338 	old_tsec = current_security();
2339 	new_tsec = bprm->cred->security;
2340 	isec = inode_security(inode);
2341 
2342 	/* Default to the current task SID. */
2343 	new_tsec->sid = old_tsec->sid;
2344 	new_tsec->osid = old_tsec->sid;
2345 
2346 	/* Reset fs, key, and sock SIDs on execve. */
2347 	new_tsec->create_sid = 0;
2348 	new_tsec->keycreate_sid = 0;
2349 	new_tsec->sockcreate_sid = 0;
2350 
2351 	if (old_tsec->exec_sid) {
2352 		new_tsec->sid = old_tsec->exec_sid;
2353 		/* Reset exec SID on execve. */
2354 		new_tsec->exec_sid = 0;
2355 
2356 		/* Fail on NNP or nosuid if not an allowed transition. */
2357 		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2358 		if (rc)
2359 			return rc;
2360 	} else {
2361 		/* Check for a default transition on this program. */
2362 		rc = security_transition_sid(&selinux_state, old_tsec->sid,
2363 					     isec->sid, SECCLASS_PROCESS, NULL,
2364 					     &new_tsec->sid);
2365 		if (rc)
2366 			return rc;
2367 
2368 		/*
2369 		 * Fallback to old SID on NNP or nosuid if not an allowed
2370 		 * transition.
2371 		 */
2372 		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2373 		if (rc)
2374 			new_tsec->sid = old_tsec->sid;
2375 	}
2376 
2377 	ad.type = LSM_AUDIT_DATA_FILE;
2378 	ad.u.file = bprm->file;
2379 
2380 	if (new_tsec->sid == old_tsec->sid) {
2381 		rc = avc_has_perm(&selinux_state,
2382 				  old_tsec->sid, isec->sid,
2383 				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2384 		if (rc)
2385 			return rc;
2386 	} else {
2387 		/* Check permissions for the transition. */
2388 		rc = avc_has_perm(&selinux_state,
2389 				  old_tsec->sid, new_tsec->sid,
2390 				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2391 		if (rc)
2392 			return rc;
2393 
2394 		rc = avc_has_perm(&selinux_state,
2395 				  new_tsec->sid, isec->sid,
2396 				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2397 		if (rc)
2398 			return rc;
2399 
2400 		/* Check for shared state */
2401 		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2402 			rc = avc_has_perm(&selinux_state,
2403 					  old_tsec->sid, new_tsec->sid,
2404 					  SECCLASS_PROCESS, PROCESS__SHARE,
2405 					  NULL);
2406 			if (rc)
2407 				return -EPERM;
2408 		}
2409 
2410 		/* Make sure that anyone attempting to ptrace over a task that
2411 		 * changes its SID has the appropriate permit */
2412 		if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2413 			u32 ptsid = ptrace_parent_sid();
2414 			if (ptsid != 0) {
2415 				rc = avc_has_perm(&selinux_state,
2416 						  ptsid, new_tsec->sid,
2417 						  SECCLASS_PROCESS,
2418 						  PROCESS__PTRACE, NULL);
2419 				if (rc)
2420 					return -EPERM;
2421 			}
2422 		}
2423 
2424 		/* Clear any possibly unsafe personality bits on exec: */
2425 		bprm->per_clear |= PER_CLEAR_ON_SETID;
2426 
2427 		/* Enable secure mode for SIDs transitions unless
2428 		   the noatsecure permission is granted between
2429 		   the two SIDs, i.e. ahp returns 0. */
2430 		rc = avc_has_perm(&selinux_state,
2431 				  old_tsec->sid, new_tsec->sid,
2432 				  SECCLASS_PROCESS, PROCESS__NOATSECURE,
2433 				  NULL);
2434 		bprm->secureexec |= !!rc;
2435 	}
2436 
2437 	return 0;
2438 }
2439 
2440 static int match_file(const void *p, struct file *file, unsigned fd)
2441 {
2442 	return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2443 }
2444 
2445 /* Derived from fs/exec.c:flush_old_files. */
2446 static inline void flush_unauthorized_files(const struct cred *cred,
2447 					    struct files_struct *files)
2448 {
2449 	struct file *file, *devnull = NULL;
2450 	struct tty_struct *tty;
2451 	int drop_tty = 0;
2452 	unsigned n;
2453 
2454 	tty = get_current_tty();
2455 	if (tty) {
2456 		spin_lock(&tty->files_lock);
2457 		if (!list_empty(&tty->tty_files)) {
2458 			struct tty_file_private *file_priv;
2459 
2460 			/* Revalidate access to controlling tty.
2461 			   Use file_path_has_perm on the tty path directly
2462 			   rather than using file_has_perm, as this particular
2463 			   open file may belong to another process and we are
2464 			   only interested in the inode-based check here. */
2465 			file_priv = list_first_entry(&tty->tty_files,
2466 						struct tty_file_private, list);
2467 			file = file_priv->file;
2468 			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2469 				drop_tty = 1;
2470 		}
2471 		spin_unlock(&tty->files_lock);
2472 		tty_kref_put(tty);
2473 	}
2474 	/* Reset controlling tty. */
2475 	if (drop_tty)
2476 		no_tty();
2477 
2478 	/* Revalidate access to inherited open files. */
2479 	n = iterate_fd(files, 0, match_file, cred);
2480 	if (!n) /* none found? */
2481 		return;
2482 
2483 	devnull = dentry_open(&selinux_null, O_RDWR, cred);
2484 	if (IS_ERR(devnull))
2485 		devnull = NULL;
2486 	/* replace all the matching ones with this */
2487 	do {
2488 		replace_fd(n - 1, devnull, 0);
2489 	} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2490 	if (devnull)
2491 		fput(devnull);
2492 }
2493 
2494 /*
2495  * Prepare a process for imminent new credential changes due to exec
2496  */
2497 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2498 {
2499 	struct task_security_struct *new_tsec;
2500 	struct rlimit *rlim, *initrlim;
2501 	int rc, i;
2502 
2503 	new_tsec = bprm->cred->security;
2504 	if (new_tsec->sid == new_tsec->osid)
2505 		return;
2506 
2507 	/* Close files for which the new task SID is not authorized. */
2508 	flush_unauthorized_files(bprm->cred, current->files);
2509 
2510 	/* Always clear parent death signal on SID transitions. */
2511 	current->pdeath_signal = 0;
2512 
2513 	/* Check whether the new SID can inherit resource limits from the old
2514 	 * SID.  If not, reset all soft limits to the lower of the current
2515 	 * task's hard limit and the init task's soft limit.
2516 	 *
2517 	 * Note that the setting of hard limits (even to lower them) can be
2518 	 * controlled by the setrlimit check.  The inclusion of the init task's
2519 	 * soft limit into the computation is to avoid resetting soft limits
2520 	 * higher than the default soft limit for cases where the default is
2521 	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2522 	 */
2523 	rc = avc_has_perm(&selinux_state,
2524 			  new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2525 			  PROCESS__RLIMITINH, NULL);
2526 	if (rc) {
2527 		/* protect against do_prlimit() */
2528 		task_lock(current);
2529 		for (i = 0; i < RLIM_NLIMITS; i++) {
2530 			rlim = current->signal->rlim + i;
2531 			initrlim = init_task.signal->rlim + i;
2532 			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2533 		}
2534 		task_unlock(current);
2535 		if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2536 			update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2537 	}
2538 }
2539 
2540 /*
2541  * Clean up the process immediately after the installation of new credentials
2542  * due to exec
2543  */
2544 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2545 {
2546 	const struct task_security_struct *tsec = current_security();
2547 	struct itimerval itimer;
2548 	u32 osid, sid;
2549 	int rc, i;
2550 
2551 	osid = tsec->osid;
2552 	sid = tsec->sid;
2553 
2554 	if (sid == osid)
2555 		return;
2556 
2557 	/* Check whether the new SID can inherit signal state from the old SID.
2558 	 * If not, clear itimers to avoid subsequent signal generation and
2559 	 * flush and unblock signals.
2560 	 *
2561 	 * This must occur _after_ the task SID has been updated so that any
2562 	 * kill done after the flush will be checked against the new SID.
2563 	 */
2564 	rc = avc_has_perm(&selinux_state,
2565 			  osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2566 	if (rc) {
2567 		if (IS_ENABLED(CONFIG_POSIX_TIMERS)) {
2568 			memset(&itimer, 0, sizeof itimer);
2569 			for (i = 0; i < 3; i++)
2570 				do_setitimer(i, &itimer, NULL);
2571 		}
2572 		spin_lock_irq(&current->sighand->siglock);
2573 		if (!fatal_signal_pending(current)) {
2574 			flush_sigqueue(&current->pending);
2575 			flush_sigqueue(&current->signal->shared_pending);
2576 			flush_signal_handlers(current, 1);
2577 			sigemptyset(&current->blocked);
2578 			recalc_sigpending();
2579 		}
2580 		spin_unlock_irq(&current->sighand->siglock);
2581 	}
2582 
2583 	/* Wake up the parent if it is waiting so that it can recheck
2584 	 * wait permission to the new task SID. */
2585 	read_lock(&tasklist_lock);
2586 	__wake_up_parent(current, current->real_parent);
2587 	read_unlock(&tasklist_lock);
2588 }
2589 
2590 /* superblock security operations */
2591 
2592 static int selinux_sb_alloc_security(struct super_block *sb)
2593 {
2594 	return superblock_alloc_security(sb);
2595 }
2596 
2597 static void selinux_sb_free_security(struct super_block *sb)
2598 {
2599 	superblock_free_security(sb);
2600 }
2601 
2602 static inline int opt_len(const char *s)
2603 {
2604 	bool open_quote = false;
2605 	int len;
2606 	char c;
2607 
2608 	for (len = 0; (c = s[len]) != '\0'; len++) {
2609 		if (c == '"')
2610 			open_quote = !open_quote;
2611 		if (c == ',' && !open_quote)
2612 			break;
2613 	}
2614 	return len;
2615 }
2616 
2617 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2618 {
2619 	char *from = options;
2620 	char *to = options;
2621 	bool first = true;
2622 
2623 	while (1) {
2624 		int len = opt_len(from);
2625 		int token, rc;
2626 		char *arg = NULL;
2627 
2628 		token = match_opt_prefix(from, len, &arg);
2629 
2630 		if (token != Opt_error) {
2631 			char *p, *q;
2632 
2633 			/* strip quotes */
2634 			if (arg) {
2635 				for (p = q = arg; p < from + len; p++) {
2636 					char c = *p;
2637 					if (c != '"')
2638 						*q++ = c;
2639 				}
2640 				arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2641 			}
2642 			rc = selinux_add_opt(token, arg, mnt_opts);
2643 			if (unlikely(rc)) {
2644 				kfree(arg);
2645 				if (*mnt_opts) {
2646 					selinux_free_mnt_opts(*mnt_opts);
2647 					*mnt_opts = NULL;
2648 				}
2649 				return rc;
2650 			}
2651 		} else {
2652 			if (!first) {	// copy with preceding comma
2653 				from--;
2654 				len++;
2655 			}
2656 			if (to != from)
2657 				memmove(to, from, len);
2658 			to += len;
2659 			first = false;
2660 		}
2661 		if (!from[len])
2662 			break;
2663 		from += len + 1;
2664 	}
2665 	*to = '\0';
2666 	return 0;
2667 }
2668 
2669 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2670 {
2671 	struct selinux_mnt_opts *opts = mnt_opts;
2672 	struct superblock_security_struct *sbsec = sb->s_security;
2673 	u32 sid;
2674 	int rc;
2675 
2676 	if (!(sbsec->flags & SE_SBINITIALIZED))
2677 		return 0;
2678 
2679 	if (!opts)
2680 		return 0;
2681 
2682 	if (opts->fscontext) {
2683 		rc = parse_sid(sb, opts->fscontext, &sid);
2684 		if (rc)
2685 			return rc;
2686 		if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2687 			goto out_bad_option;
2688 	}
2689 	if (opts->context) {
2690 		rc = parse_sid(sb, opts->context, &sid);
2691 		if (rc)
2692 			return rc;
2693 		if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2694 			goto out_bad_option;
2695 	}
2696 	if (opts->rootcontext) {
2697 		struct inode_security_struct *root_isec;
2698 		root_isec = backing_inode_security(sb->s_root);
2699 		rc = parse_sid(sb, opts->rootcontext, &sid);
2700 		if (rc)
2701 			return rc;
2702 		if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2703 			goto out_bad_option;
2704 	}
2705 	if (opts->defcontext) {
2706 		rc = parse_sid(sb, opts->defcontext, &sid);
2707 		if (rc)
2708 			return rc;
2709 		if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2710 			goto out_bad_option;
2711 	}
2712 	return 0;
2713 
2714 out_bad_option:
2715 	pr_warn("SELinux: unable to change security options "
2716 	       "during remount (dev %s, type=%s)\n", sb->s_id,
2717 	       sb->s_type->name);
2718 	return -EINVAL;
2719 }
2720 
2721 static int selinux_sb_kern_mount(struct super_block *sb)
2722 {
2723 	const struct cred *cred = current_cred();
2724 	struct common_audit_data ad;
2725 
2726 	ad.type = LSM_AUDIT_DATA_DENTRY;
2727 	ad.u.dentry = sb->s_root;
2728 	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2729 }
2730 
2731 static int selinux_sb_statfs(struct dentry *dentry)
2732 {
2733 	const struct cred *cred = current_cred();
2734 	struct common_audit_data ad;
2735 
2736 	ad.type = LSM_AUDIT_DATA_DENTRY;
2737 	ad.u.dentry = dentry->d_sb->s_root;
2738 	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2739 }
2740 
2741 static int selinux_mount(const char *dev_name,
2742 			 const struct path *path,
2743 			 const char *type,
2744 			 unsigned long flags,
2745 			 void *data)
2746 {
2747 	const struct cred *cred = current_cred();
2748 
2749 	if (flags & MS_REMOUNT)
2750 		return superblock_has_perm(cred, path->dentry->d_sb,
2751 					   FILESYSTEM__REMOUNT, NULL);
2752 	else
2753 		return path_has_perm(cred, path, FILE__MOUNTON);
2754 }
2755 
2756 static int selinux_umount(struct vfsmount *mnt, int flags)
2757 {
2758 	const struct cred *cred = current_cred();
2759 
2760 	return superblock_has_perm(cred, mnt->mnt_sb,
2761 				   FILESYSTEM__UNMOUNT, NULL);
2762 }
2763 
2764 /* inode security operations */
2765 
2766 static int selinux_inode_alloc_security(struct inode *inode)
2767 {
2768 	return inode_alloc_security(inode);
2769 }
2770 
2771 static void selinux_inode_free_security(struct inode *inode)
2772 {
2773 	inode_free_security(inode);
2774 }
2775 
2776 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2777 					const struct qstr *name, void **ctx,
2778 					u32 *ctxlen)
2779 {
2780 	u32 newsid;
2781 	int rc;
2782 
2783 	rc = selinux_determine_inode_label(current_security(),
2784 					   d_inode(dentry->d_parent), name,
2785 					   inode_mode_to_security_class(mode),
2786 					   &newsid);
2787 	if (rc)
2788 		return rc;
2789 
2790 	return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
2791 				       ctxlen);
2792 }
2793 
2794 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2795 					  struct qstr *name,
2796 					  const struct cred *old,
2797 					  struct cred *new)
2798 {
2799 	u32 newsid;
2800 	int rc;
2801 	struct task_security_struct *tsec;
2802 
2803 	rc = selinux_determine_inode_label(old->security,
2804 					   d_inode(dentry->d_parent), name,
2805 					   inode_mode_to_security_class(mode),
2806 					   &newsid);
2807 	if (rc)
2808 		return rc;
2809 
2810 	tsec = new->security;
2811 	tsec->create_sid = newsid;
2812 	return 0;
2813 }
2814 
2815 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2816 				       const struct qstr *qstr,
2817 				       const char **name,
2818 				       void **value, size_t *len)
2819 {
2820 	const struct task_security_struct *tsec = current_security();
2821 	struct superblock_security_struct *sbsec;
2822 	u32 newsid, clen;
2823 	int rc;
2824 	char *context;
2825 
2826 	sbsec = dir->i_sb->s_security;
2827 
2828 	newsid = tsec->create_sid;
2829 
2830 	rc = selinux_determine_inode_label(current_security(),
2831 		dir, qstr,
2832 		inode_mode_to_security_class(inode->i_mode),
2833 		&newsid);
2834 	if (rc)
2835 		return rc;
2836 
2837 	/* Possibly defer initialization to selinux_complete_init. */
2838 	if (sbsec->flags & SE_SBINITIALIZED) {
2839 		struct inode_security_struct *isec = inode->i_security;
2840 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
2841 		isec->sid = newsid;
2842 		isec->initialized = LABEL_INITIALIZED;
2843 	}
2844 
2845 	if (!selinux_state.initialized || !(sbsec->flags & SBLABEL_MNT))
2846 		return -EOPNOTSUPP;
2847 
2848 	if (name)
2849 		*name = XATTR_SELINUX_SUFFIX;
2850 
2851 	if (value && len) {
2852 		rc = security_sid_to_context_force(&selinux_state, newsid,
2853 						   &context, &clen);
2854 		if (rc)
2855 			return rc;
2856 		*value = context;
2857 		*len = clen;
2858 	}
2859 
2860 	return 0;
2861 }
2862 
2863 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2864 {
2865 	return may_create(dir, dentry, SECCLASS_FILE);
2866 }
2867 
2868 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2869 {
2870 	return may_link(dir, old_dentry, MAY_LINK);
2871 }
2872 
2873 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2874 {
2875 	return may_link(dir, dentry, MAY_UNLINK);
2876 }
2877 
2878 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2879 {
2880 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
2881 }
2882 
2883 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2884 {
2885 	return may_create(dir, dentry, SECCLASS_DIR);
2886 }
2887 
2888 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2889 {
2890 	return may_link(dir, dentry, MAY_RMDIR);
2891 }
2892 
2893 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2894 {
2895 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
2896 }
2897 
2898 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2899 				struct inode *new_inode, struct dentry *new_dentry)
2900 {
2901 	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2902 }
2903 
2904 static int selinux_inode_readlink(struct dentry *dentry)
2905 {
2906 	const struct cred *cred = current_cred();
2907 
2908 	return dentry_has_perm(cred, dentry, FILE__READ);
2909 }
2910 
2911 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2912 				     bool rcu)
2913 {
2914 	const struct cred *cred = current_cred();
2915 	struct common_audit_data ad;
2916 	struct inode_security_struct *isec;
2917 	u32 sid;
2918 
2919 	validate_creds(cred);
2920 
2921 	ad.type = LSM_AUDIT_DATA_DENTRY;
2922 	ad.u.dentry = dentry;
2923 	sid = cred_sid(cred);
2924 	isec = inode_security_rcu(inode, rcu);
2925 	if (IS_ERR(isec))
2926 		return PTR_ERR(isec);
2927 
2928 	return avc_has_perm_flags(&selinux_state,
2929 				  sid, isec->sid, isec->sclass, FILE__READ, &ad,
2930 				  rcu ? MAY_NOT_BLOCK : 0);
2931 }
2932 
2933 static noinline int audit_inode_permission(struct inode *inode,
2934 					   u32 perms, u32 audited, u32 denied,
2935 					   int result,
2936 					   unsigned flags)
2937 {
2938 	struct common_audit_data ad;
2939 	struct inode_security_struct *isec = inode->i_security;
2940 	int rc;
2941 
2942 	ad.type = LSM_AUDIT_DATA_INODE;
2943 	ad.u.inode = inode;
2944 
2945 	rc = slow_avc_audit(&selinux_state,
2946 			    current_sid(), isec->sid, isec->sclass, perms,
2947 			    audited, denied, result, &ad, flags);
2948 	if (rc)
2949 		return rc;
2950 	return 0;
2951 }
2952 
2953 static int selinux_inode_permission(struct inode *inode, int mask)
2954 {
2955 	const struct cred *cred = current_cred();
2956 	u32 perms;
2957 	bool from_access;
2958 	unsigned flags = mask & MAY_NOT_BLOCK;
2959 	struct inode_security_struct *isec;
2960 	u32 sid;
2961 	struct av_decision avd;
2962 	int rc, rc2;
2963 	u32 audited, denied;
2964 
2965 	from_access = mask & MAY_ACCESS;
2966 	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2967 
2968 	/* No permission to check.  Existence test. */
2969 	if (!mask)
2970 		return 0;
2971 
2972 	validate_creds(cred);
2973 
2974 	if (unlikely(IS_PRIVATE(inode)))
2975 		return 0;
2976 
2977 	perms = file_mask_to_av(inode->i_mode, mask);
2978 
2979 	sid = cred_sid(cred);
2980 	isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
2981 	if (IS_ERR(isec))
2982 		return PTR_ERR(isec);
2983 
2984 	rc = avc_has_perm_noaudit(&selinux_state,
2985 				  sid, isec->sid, isec->sclass, perms, 0, &avd);
2986 	audited = avc_audit_required(perms, &avd, rc,
2987 				     from_access ? FILE__AUDIT_ACCESS : 0,
2988 				     &denied);
2989 	if (likely(!audited))
2990 		return rc;
2991 
2992 	rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
2993 	if (rc2)
2994 		return rc2;
2995 	return rc;
2996 }
2997 
2998 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2999 {
3000 	const struct cred *cred = current_cred();
3001 	struct inode *inode = d_backing_inode(dentry);
3002 	unsigned int ia_valid = iattr->ia_valid;
3003 	__u32 av = FILE__WRITE;
3004 
3005 	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3006 	if (ia_valid & ATTR_FORCE) {
3007 		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3008 			      ATTR_FORCE);
3009 		if (!ia_valid)
3010 			return 0;
3011 	}
3012 
3013 	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3014 			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3015 		return dentry_has_perm(cred, dentry, FILE__SETATTR);
3016 
3017 	if (selinux_policycap_openperm() &&
3018 	    inode->i_sb->s_magic != SOCKFS_MAGIC &&
3019 	    (ia_valid & ATTR_SIZE) &&
3020 	    !(ia_valid & ATTR_FILE))
3021 		av |= FILE__OPEN;
3022 
3023 	return dentry_has_perm(cred, dentry, av);
3024 }
3025 
3026 static int selinux_inode_getattr(const struct path *path)
3027 {
3028 	return path_has_perm(current_cred(), path, FILE__GETATTR);
3029 }
3030 
3031 static bool has_cap_mac_admin(bool audit)
3032 {
3033 	const struct cred *cred = current_cred();
3034 	int cap_audit = audit ? SECURITY_CAP_AUDIT : SECURITY_CAP_NOAUDIT;
3035 
3036 	if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, cap_audit))
3037 		return false;
3038 	if (cred_has_capability(cred, CAP_MAC_ADMIN, cap_audit, true))
3039 		return false;
3040 	return true;
3041 }
3042 
3043 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3044 				  const void *value, size_t size, int flags)
3045 {
3046 	struct inode *inode = d_backing_inode(dentry);
3047 	struct inode_security_struct *isec;
3048 	struct superblock_security_struct *sbsec;
3049 	struct common_audit_data ad;
3050 	u32 newsid, sid = current_sid();
3051 	int rc = 0;
3052 
3053 	if (strcmp(name, XATTR_NAME_SELINUX)) {
3054 		rc = cap_inode_setxattr(dentry, name, value, size, flags);
3055 		if (rc)
3056 			return rc;
3057 
3058 		/* Not an attribute we recognize, so just check the
3059 		   ordinary setattr permission. */
3060 		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3061 	}
3062 
3063 	sbsec = inode->i_sb->s_security;
3064 	if (!(sbsec->flags & SBLABEL_MNT))
3065 		return -EOPNOTSUPP;
3066 
3067 	if (!inode_owner_or_capable(inode))
3068 		return -EPERM;
3069 
3070 	ad.type = LSM_AUDIT_DATA_DENTRY;
3071 	ad.u.dentry = dentry;
3072 
3073 	isec = backing_inode_security(dentry);
3074 	rc = avc_has_perm(&selinux_state,
3075 			  sid, isec->sid, isec->sclass,
3076 			  FILE__RELABELFROM, &ad);
3077 	if (rc)
3078 		return rc;
3079 
3080 	rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3081 				     GFP_KERNEL);
3082 	if (rc == -EINVAL) {
3083 		if (!has_cap_mac_admin(true)) {
3084 			struct audit_buffer *ab;
3085 			size_t audit_size;
3086 
3087 			/* We strip a nul only if it is at the end, otherwise the
3088 			 * context contains a nul and we should audit that */
3089 			if (value) {
3090 				const char *str = value;
3091 
3092 				if (str[size - 1] == '\0')
3093 					audit_size = size - 1;
3094 				else
3095 					audit_size = size;
3096 			} else {
3097 				audit_size = 0;
3098 			}
3099 			ab = audit_log_start(audit_context(),
3100 					     GFP_ATOMIC, AUDIT_SELINUX_ERR);
3101 			audit_log_format(ab, "op=setxattr invalid_context=");
3102 			audit_log_n_untrustedstring(ab, value, audit_size);
3103 			audit_log_end(ab);
3104 
3105 			return rc;
3106 		}
3107 		rc = security_context_to_sid_force(&selinux_state, value,
3108 						   size, &newsid);
3109 	}
3110 	if (rc)
3111 		return rc;
3112 
3113 	rc = avc_has_perm(&selinux_state,
3114 			  sid, newsid, isec->sclass,
3115 			  FILE__RELABELTO, &ad);
3116 	if (rc)
3117 		return rc;
3118 
3119 	rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3120 					  sid, isec->sclass);
3121 	if (rc)
3122 		return rc;
3123 
3124 	return avc_has_perm(&selinux_state,
3125 			    newsid,
3126 			    sbsec->sid,
3127 			    SECCLASS_FILESYSTEM,
3128 			    FILESYSTEM__ASSOCIATE,
3129 			    &ad);
3130 }
3131 
3132 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3133 					const void *value, size_t size,
3134 					int flags)
3135 {
3136 	struct inode *inode = d_backing_inode(dentry);
3137 	struct inode_security_struct *isec;
3138 	u32 newsid;
3139 	int rc;
3140 
3141 	if (strcmp(name, XATTR_NAME_SELINUX)) {
3142 		/* Not an attribute we recognize, so nothing to do. */
3143 		return;
3144 	}
3145 
3146 	rc = security_context_to_sid_force(&selinux_state, value, size,
3147 					   &newsid);
3148 	if (rc) {
3149 		pr_err("SELinux:  unable to map context to SID"
3150 		       "for (%s, %lu), rc=%d\n",
3151 		       inode->i_sb->s_id, inode->i_ino, -rc);
3152 		return;
3153 	}
3154 
3155 	isec = backing_inode_security(dentry);
3156 	spin_lock(&isec->lock);
3157 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3158 	isec->sid = newsid;
3159 	isec->initialized = LABEL_INITIALIZED;
3160 	spin_unlock(&isec->lock);
3161 
3162 	return;
3163 }
3164 
3165 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3166 {
3167 	const struct cred *cred = current_cred();
3168 
3169 	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3170 }
3171 
3172 static int selinux_inode_listxattr(struct dentry *dentry)
3173 {
3174 	const struct cred *cred = current_cred();
3175 
3176 	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3177 }
3178 
3179 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3180 {
3181 	if (strcmp(name, XATTR_NAME_SELINUX)) {
3182 		int rc = cap_inode_removexattr(dentry, name);
3183 		if (rc)
3184 			return rc;
3185 
3186 		/* Not an attribute we recognize, so just check the
3187 		   ordinary setattr permission. */
3188 		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3189 	}
3190 
3191 	/* No one is allowed to remove a SELinux security label.
3192 	   You can change the label, but all data must be labeled. */
3193 	return -EACCES;
3194 }
3195 
3196 /*
3197  * Copy the inode security context value to the user.
3198  *
3199  * Permission check is handled by selinux_inode_getxattr hook.
3200  */
3201 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3202 {
3203 	u32 size;
3204 	int error;
3205 	char *context = NULL;
3206 	struct inode_security_struct *isec;
3207 
3208 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
3209 		return -EOPNOTSUPP;
3210 
3211 	/*
3212 	 * If the caller has CAP_MAC_ADMIN, then get the raw context
3213 	 * value even if it is not defined by current policy; otherwise,
3214 	 * use the in-core value under current policy.
3215 	 * Use the non-auditing forms of the permission checks since
3216 	 * getxattr may be called by unprivileged processes commonly
3217 	 * and lack of permission just means that we fall back to the
3218 	 * in-core context value, not a denial.
3219 	 */
3220 	isec = inode_security(inode);
3221 	if (has_cap_mac_admin(false))
3222 		error = security_sid_to_context_force(&selinux_state,
3223 						      isec->sid, &context,
3224 						      &size);
3225 	else
3226 		error = security_sid_to_context(&selinux_state, isec->sid,
3227 						&context, &size);
3228 	if (error)
3229 		return error;
3230 	error = size;
3231 	if (alloc) {
3232 		*buffer = context;
3233 		goto out_nofree;
3234 	}
3235 	kfree(context);
3236 out_nofree:
3237 	return error;
3238 }
3239 
3240 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3241 				     const void *value, size_t size, int flags)
3242 {
3243 	struct inode_security_struct *isec = inode_security_novalidate(inode);
3244 	u32 newsid;
3245 	int rc;
3246 
3247 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
3248 		return -EOPNOTSUPP;
3249 
3250 	if (!value || !size)
3251 		return -EACCES;
3252 
3253 	rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3254 				     GFP_KERNEL);
3255 	if (rc)
3256 		return rc;
3257 
3258 	spin_lock(&isec->lock);
3259 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3260 	isec->sid = newsid;
3261 	isec->initialized = LABEL_INITIALIZED;
3262 	spin_unlock(&isec->lock);
3263 	return 0;
3264 }
3265 
3266 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3267 {
3268 	const int len = sizeof(XATTR_NAME_SELINUX);
3269 	if (buffer && len <= buffer_size)
3270 		memcpy(buffer, XATTR_NAME_SELINUX, len);
3271 	return len;
3272 }
3273 
3274 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3275 {
3276 	struct inode_security_struct *isec = inode_security_novalidate(inode);
3277 	*secid = isec->sid;
3278 }
3279 
3280 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3281 {
3282 	u32 sid;
3283 	struct task_security_struct *tsec;
3284 	struct cred *new_creds = *new;
3285 
3286 	if (new_creds == NULL) {
3287 		new_creds = prepare_creds();
3288 		if (!new_creds)
3289 			return -ENOMEM;
3290 	}
3291 
3292 	tsec = new_creds->security;
3293 	/* Get label from overlay inode and set it in create_sid */
3294 	selinux_inode_getsecid(d_inode(src), &sid);
3295 	tsec->create_sid = sid;
3296 	*new = new_creds;
3297 	return 0;
3298 }
3299 
3300 static int selinux_inode_copy_up_xattr(const char *name)
3301 {
3302 	/* The copy_up hook above sets the initial context on an inode, but we
3303 	 * don't then want to overwrite it by blindly copying all the lower
3304 	 * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3305 	 */
3306 	if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3307 		return 1; /* Discard */
3308 	/*
3309 	 * Any other attribute apart from SELINUX is not claimed, supported
3310 	 * by selinux.
3311 	 */
3312 	return -EOPNOTSUPP;
3313 }
3314 
3315 /* file security operations */
3316 
3317 static int selinux_revalidate_file_permission(struct file *file, int mask)
3318 {
3319 	const struct cred *cred = current_cred();
3320 	struct inode *inode = file_inode(file);
3321 
3322 	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3323 	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3324 		mask |= MAY_APPEND;
3325 
3326 	return file_has_perm(cred, file,
3327 			     file_mask_to_av(inode->i_mode, mask));
3328 }
3329 
3330 static int selinux_file_permission(struct file *file, int mask)
3331 {
3332 	struct inode *inode = file_inode(file);
3333 	struct file_security_struct *fsec = file->f_security;
3334 	struct inode_security_struct *isec;
3335 	u32 sid = current_sid();
3336 
3337 	if (!mask)
3338 		/* No permission to check.  Existence test. */
3339 		return 0;
3340 
3341 	isec = inode_security(inode);
3342 	if (sid == fsec->sid && fsec->isid == isec->sid &&
3343 	    fsec->pseqno == avc_policy_seqno(&selinux_state))
3344 		/* No change since file_open check. */
3345 		return 0;
3346 
3347 	return selinux_revalidate_file_permission(file, mask);
3348 }
3349 
3350 static int selinux_file_alloc_security(struct file *file)
3351 {
3352 	return file_alloc_security(file);
3353 }
3354 
3355 static void selinux_file_free_security(struct file *file)
3356 {
3357 	file_free_security(file);
3358 }
3359 
3360 /*
3361  * Check whether a task has the ioctl permission and cmd
3362  * operation to an inode.
3363  */
3364 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3365 		u32 requested, u16 cmd)
3366 {
3367 	struct common_audit_data ad;
3368 	struct file_security_struct *fsec = file->f_security;
3369 	struct inode *inode = file_inode(file);
3370 	struct inode_security_struct *isec;
3371 	struct lsm_ioctlop_audit ioctl;
3372 	u32 ssid = cred_sid(cred);
3373 	int rc;
3374 	u8 driver = cmd >> 8;
3375 	u8 xperm = cmd & 0xff;
3376 
3377 	ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3378 	ad.u.op = &ioctl;
3379 	ad.u.op->cmd = cmd;
3380 	ad.u.op->path = file->f_path;
3381 
3382 	if (ssid != fsec->sid) {
3383 		rc = avc_has_perm(&selinux_state,
3384 				  ssid, fsec->sid,
3385 				SECCLASS_FD,
3386 				FD__USE,
3387 				&ad);
3388 		if (rc)
3389 			goto out;
3390 	}
3391 
3392 	if (unlikely(IS_PRIVATE(inode)))
3393 		return 0;
3394 
3395 	isec = inode_security(inode);
3396 	rc = avc_has_extended_perms(&selinux_state,
3397 				    ssid, isec->sid, isec->sclass,
3398 				    requested, driver, xperm, &ad);
3399 out:
3400 	return rc;
3401 }
3402 
3403 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3404 			      unsigned long arg)
3405 {
3406 	const struct cred *cred = current_cred();
3407 	int error = 0;
3408 
3409 	switch (cmd) {
3410 	case FIONREAD:
3411 	/* fall through */
3412 	case FIBMAP:
3413 	/* fall through */
3414 	case FIGETBSZ:
3415 	/* fall through */
3416 	case FS_IOC_GETFLAGS:
3417 	/* fall through */
3418 	case FS_IOC_GETVERSION:
3419 		error = file_has_perm(cred, file, FILE__GETATTR);
3420 		break;
3421 
3422 	case FS_IOC_SETFLAGS:
3423 	/* fall through */
3424 	case FS_IOC_SETVERSION:
3425 		error = file_has_perm(cred, file, FILE__SETATTR);
3426 		break;
3427 
3428 	/* sys_ioctl() checks */
3429 	case FIONBIO:
3430 	/* fall through */
3431 	case FIOASYNC:
3432 		error = file_has_perm(cred, file, 0);
3433 		break;
3434 
3435 	case KDSKBENT:
3436 	case KDSKBSENT:
3437 		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3438 					    SECURITY_CAP_AUDIT, true);
3439 		break;
3440 
3441 	/* default case assumes that the command will go
3442 	 * to the file's ioctl() function.
3443 	 */
3444 	default:
3445 		error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3446 	}
3447 	return error;
3448 }
3449 
3450 static int default_noexec;
3451 
3452 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3453 {
3454 	const struct cred *cred = current_cred();
3455 	u32 sid = cred_sid(cred);
3456 	int rc = 0;
3457 
3458 	if (default_noexec &&
3459 	    (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3460 				   (!shared && (prot & PROT_WRITE)))) {
3461 		/*
3462 		 * We are making executable an anonymous mapping or a
3463 		 * private file mapping that will also be writable.
3464 		 * This has an additional check.
3465 		 */
3466 		rc = avc_has_perm(&selinux_state,
3467 				  sid, sid, SECCLASS_PROCESS,
3468 				  PROCESS__EXECMEM, NULL);
3469 		if (rc)
3470 			goto error;
3471 	}
3472 
3473 	if (file) {
3474 		/* read access is always possible with a mapping */
3475 		u32 av = FILE__READ;
3476 
3477 		/* write access only matters if the mapping is shared */
3478 		if (shared && (prot & PROT_WRITE))
3479 			av |= FILE__WRITE;
3480 
3481 		if (prot & PROT_EXEC)
3482 			av |= FILE__EXECUTE;
3483 
3484 		return file_has_perm(cred, file, av);
3485 	}
3486 
3487 error:
3488 	return rc;
3489 }
3490 
3491 static int selinux_mmap_addr(unsigned long addr)
3492 {
3493 	int rc = 0;
3494 
3495 	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3496 		u32 sid = current_sid();
3497 		rc = avc_has_perm(&selinux_state,
3498 				  sid, sid, SECCLASS_MEMPROTECT,
3499 				  MEMPROTECT__MMAP_ZERO, NULL);
3500 	}
3501 
3502 	return rc;
3503 }
3504 
3505 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3506 			     unsigned long prot, unsigned long flags)
3507 {
3508 	struct common_audit_data ad;
3509 	int rc;
3510 
3511 	if (file) {
3512 		ad.type = LSM_AUDIT_DATA_FILE;
3513 		ad.u.file = file;
3514 		rc = inode_has_perm(current_cred(), file_inode(file),
3515 				    FILE__MAP, &ad);
3516 		if (rc)
3517 			return rc;
3518 	}
3519 
3520 	if (selinux_state.checkreqprot)
3521 		prot = reqprot;
3522 
3523 	return file_map_prot_check(file, prot,
3524 				   (flags & MAP_TYPE) == MAP_SHARED);
3525 }
3526 
3527 static int selinux_file_mprotect(struct vm_area_struct *vma,
3528 				 unsigned long reqprot,
3529 				 unsigned long prot)
3530 {
3531 	const struct cred *cred = current_cred();
3532 	u32 sid = cred_sid(cred);
3533 
3534 	if (selinux_state.checkreqprot)
3535 		prot = reqprot;
3536 
3537 	if (default_noexec &&
3538 	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3539 		int rc = 0;
3540 		if (vma->vm_start >= vma->vm_mm->start_brk &&
3541 		    vma->vm_end <= vma->vm_mm->brk) {
3542 			rc = avc_has_perm(&selinux_state,
3543 					  sid, sid, SECCLASS_PROCESS,
3544 					  PROCESS__EXECHEAP, NULL);
3545 		} else if (!vma->vm_file &&
3546 			   ((vma->vm_start <= vma->vm_mm->start_stack &&
3547 			     vma->vm_end >= vma->vm_mm->start_stack) ||
3548 			    vma_is_stack_for_current(vma))) {
3549 			rc = avc_has_perm(&selinux_state,
3550 					  sid, sid, SECCLASS_PROCESS,
3551 					  PROCESS__EXECSTACK, NULL);
3552 		} else if (vma->vm_file && vma->anon_vma) {
3553 			/*
3554 			 * We are making executable a file mapping that has
3555 			 * had some COW done. Since pages might have been
3556 			 * written, check ability to execute the possibly
3557 			 * modified content.  This typically should only
3558 			 * occur for text relocations.
3559 			 */
3560 			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3561 		}
3562 		if (rc)
3563 			return rc;
3564 	}
3565 
3566 	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3567 }
3568 
3569 static int selinux_file_lock(struct file *file, unsigned int cmd)
3570 {
3571 	const struct cred *cred = current_cred();
3572 
3573 	return file_has_perm(cred, file, FILE__LOCK);
3574 }
3575 
3576 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3577 			      unsigned long arg)
3578 {
3579 	const struct cred *cred = current_cred();
3580 	int err = 0;
3581 
3582 	switch (cmd) {
3583 	case F_SETFL:
3584 		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3585 			err = file_has_perm(cred, file, FILE__WRITE);
3586 			break;
3587 		}
3588 		/* fall through */
3589 	case F_SETOWN:
3590 	case F_SETSIG:
3591 	case F_GETFL:
3592 	case F_GETOWN:
3593 	case F_GETSIG:
3594 	case F_GETOWNER_UIDS:
3595 		/* Just check FD__USE permission */
3596 		err = file_has_perm(cred, file, 0);
3597 		break;
3598 	case F_GETLK:
3599 	case F_SETLK:
3600 	case F_SETLKW:
3601 	case F_OFD_GETLK:
3602 	case F_OFD_SETLK:
3603 	case F_OFD_SETLKW:
3604 #if BITS_PER_LONG == 32
3605 	case F_GETLK64:
3606 	case F_SETLK64:
3607 	case F_SETLKW64:
3608 #endif
3609 		err = file_has_perm(cred, file, FILE__LOCK);
3610 		break;
3611 	}
3612 
3613 	return err;
3614 }
3615 
3616 static void selinux_file_set_fowner(struct file *file)
3617 {
3618 	struct file_security_struct *fsec;
3619 
3620 	fsec = file->f_security;
3621 	fsec->fown_sid = current_sid();
3622 }
3623 
3624 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3625 				       struct fown_struct *fown, int signum)
3626 {
3627 	struct file *file;
3628 	u32 sid = task_sid(tsk);
3629 	u32 perm;
3630 	struct file_security_struct *fsec;
3631 
3632 	/* struct fown_struct is never outside the context of a struct file */
3633 	file = container_of(fown, struct file, f_owner);
3634 
3635 	fsec = file->f_security;
3636 
3637 	if (!signum)
3638 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3639 	else
3640 		perm = signal_to_av(signum);
3641 
3642 	return avc_has_perm(&selinux_state,
3643 			    fsec->fown_sid, sid,
3644 			    SECCLASS_PROCESS, perm, NULL);
3645 }
3646 
3647 static int selinux_file_receive(struct file *file)
3648 {
3649 	const struct cred *cred = current_cred();
3650 
3651 	return file_has_perm(cred, file, file_to_av(file));
3652 }
3653 
3654 static int selinux_file_open(struct file *file)
3655 {
3656 	struct file_security_struct *fsec;
3657 	struct inode_security_struct *isec;
3658 
3659 	fsec = file->f_security;
3660 	isec = inode_security(file_inode(file));
3661 	/*
3662 	 * Save inode label and policy sequence number
3663 	 * at open-time so that selinux_file_permission
3664 	 * can determine whether revalidation is necessary.
3665 	 * Task label is already saved in the file security
3666 	 * struct as its SID.
3667 	 */
3668 	fsec->isid = isec->sid;
3669 	fsec->pseqno = avc_policy_seqno(&selinux_state);
3670 	/*
3671 	 * Since the inode label or policy seqno may have changed
3672 	 * between the selinux_inode_permission check and the saving
3673 	 * of state above, recheck that access is still permitted.
3674 	 * Otherwise, access might never be revalidated against the
3675 	 * new inode label or new policy.
3676 	 * This check is not redundant - do not remove.
3677 	 */
3678 	return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3679 }
3680 
3681 /* task security operations */
3682 
3683 static int selinux_task_alloc(struct task_struct *task,
3684 			      unsigned long clone_flags)
3685 {
3686 	u32 sid = current_sid();
3687 
3688 	return avc_has_perm(&selinux_state,
3689 			    sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3690 }
3691 
3692 /*
3693  * allocate the SELinux part of blank credentials
3694  */
3695 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3696 {
3697 	struct task_security_struct *tsec;
3698 
3699 	tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3700 	if (!tsec)
3701 		return -ENOMEM;
3702 
3703 	cred->security = tsec;
3704 	return 0;
3705 }
3706 
3707 /*
3708  * detach and free the LSM part of a set of credentials
3709  */
3710 static void selinux_cred_free(struct cred *cred)
3711 {
3712 	struct task_security_struct *tsec = cred->security;
3713 
3714 	/*
3715 	 * cred->security == NULL if security_cred_alloc_blank() or
3716 	 * security_prepare_creds() returned an error.
3717 	 */
3718 	BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3719 	cred->security = (void *) 0x7UL;
3720 	kfree(tsec);
3721 }
3722 
3723 /*
3724  * prepare a new set of credentials for modification
3725  */
3726 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3727 				gfp_t gfp)
3728 {
3729 	const struct task_security_struct *old_tsec;
3730 	struct task_security_struct *tsec;
3731 
3732 	old_tsec = old->security;
3733 
3734 	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3735 	if (!tsec)
3736 		return -ENOMEM;
3737 
3738 	new->security = tsec;
3739 	return 0;
3740 }
3741 
3742 /*
3743  * transfer the SELinux data to a blank set of creds
3744  */
3745 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3746 {
3747 	const struct task_security_struct *old_tsec = old->security;
3748 	struct task_security_struct *tsec = new->security;
3749 
3750 	*tsec = *old_tsec;
3751 }
3752 
3753 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3754 {
3755 	*secid = cred_sid(c);
3756 }
3757 
3758 /*
3759  * set the security data for a kernel service
3760  * - all the creation contexts are set to unlabelled
3761  */
3762 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3763 {
3764 	struct task_security_struct *tsec = new->security;
3765 	u32 sid = current_sid();
3766 	int ret;
3767 
3768 	ret = avc_has_perm(&selinux_state,
3769 			   sid, secid,
3770 			   SECCLASS_KERNEL_SERVICE,
3771 			   KERNEL_SERVICE__USE_AS_OVERRIDE,
3772 			   NULL);
3773 	if (ret == 0) {
3774 		tsec->sid = secid;
3775 		tsec->create_sid = 0;
3776 		tsec->keycreate_sid = 0;
3777 		tsec->sockcreate_sid = 0;
3778 	}
3779 	return ret;
3780 }
3781 
3782 /*
3783  * set the file creation context in a security record to the same as the
3784  * objective context of the specified inode
3785  */
3786 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3787 {
3788 	struct inode_security_struct *isec = inode_security(inode);
3789 	struct task_security_struct *tsec = new->security;
3790 	u32 sid = current_sid();
3791 	int ret;
3792 
3793 	ret = avc_has_perm(&selinux_state,
3794 			   sid, isec->sid,
3795 			   SECCLASS_KERNEL_SERVICE,
3796 			   KERNEL_SERVICE__CREATE_FILES_AS,
3797 			   NULL);
3798 
3799 	if (ret == 0)
3800 		tsec->create_sid = isec->sid;
3801 	return ret;
3802 }
3803 
3804 static int selinux_kernel_module_request(char *kmod_name)
3805 {
3806 	struct common_audit_data ad;
3807 
3808 	ad.type = LSM_AUDIT_DATA_KMOD;
3809 	ad.u.kmod_name = kmod_name;
3810 
3811 	return avc_has_perm(&selinux_state,
3812 			    current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
3813 			    SYSTEM__MODULE_REQUEST, &ad);
3814 }
3815 
3816 static int selinux_kernel_module_from_file(struct file *file)
3817 {
3818 	struct common_audit_data ad;
3819 	struct inode_security_struct *isec;
3820 	struct file_security_struct *fsec;
3821 	u32 sid = current_sid();
3822 	int rc;
3823 
3824 	/* init_module */
3825 	if (file == NULL)
3826 		return avc_has_perm(&selinux_state,
3827 				    sid, sid, SECCLASS_SYSTEM,
3828 					SYSTEM__MODULE_LOAD, NULL);
3829 
3830 	/* finit_module */
3831 
3832 	ad.type = LSM_AUDIT_DATA_FILE;
3833 	ad.u.file = file;
3834 
3835 	fsec = file->f_security;
3836 	if (sid != fsec->sid) {
3837 		rc = avc_has_perm(&selinux_state,
3838 				  sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
3839 		if (rc)
3840 			return rc;
3841 	}
3842 
3843 	isec = inode_security(file_inode(file));
3844 	return avc_has_perm(&selinux_state,
3845 			    sid, isec->sid, SECCLASS_SYSTEM,
3846 				SYSTEM__MODULE_LOAD, &ad);
3847 }
3848 
3849 static int selinux_kernel_read_file(struct file *file,
3850 				    enum kernel_read_file_id id)
3851 {
3852 	int rc = 0;
3853 
3854 	switch (id) {
3855 	case READING_MODULE:
3856 		rc = selinux_kernel_module_from_file(file);
3857 		break;
3858 	default:
3859 		break;
3860 	}
3861 
3862 	return rc;
3863 }
3864 
3865 static int selinux_kernel_load_data(enum kernel_load_data_id id)
3866 {
3867 	int rc = 0;
3868 
3869 	switch (id) {
3870 	case LOADING_MODULE:
3871 		rc = selinux_kernel_module_from_file(NULL);
3872 	default:
3873 		break;
3874 	}
3875 
3876 	return rc;
3877 }
3878 
3879 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3880 {
3881 	return avc_has_perm(&selinux_state,
3882 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
3883 			    PROCESS__SETPGID, NULL);
3884 }
3885 
3886 static int selinux_task_getpgid(struct task_struct *p)
3887 {
3888 	return avc_has_perm(&selinux_state,
3889 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
3890 			    PROCESS__GETPGID, NULL);
3891 }
3892 
3893 static int selinux_task_getsid(struct task_struct *p)
3894 {
3895 	return avc_has_perm(&selinux_state,
3896 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
3897 			    PROCESS__GETSESSION, NULL);
3898 }
3899 
3900 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3901 {
3902 	*secid = task_sid(p);
3903 }
3904 
3905 static int selinux_task_setnice(struct task_struct *p, int nice)
3906 {
3907 	return avc_has_perm(&selinux_state,
3908 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
3909 			    PROCESS__SETSCHED, NULL);
3910 }
3911 
3912 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3913 {
3914 	return avc_has_perm(&selinux_state,
3915 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
3916 			    PROCESS__SETSCHED, NULL);
3917 }
3918 
3919 static int selinux_task_getioprio(struct task_struct *p)
3920 {
3921 	return avc_has_perm(&selinux_state,
3922 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
3923 			    PROCESS__GETSCHED, NULL);
3924 }
3925 
3926 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
3927 				unsigned int flags)
3928 {
3929 	u32 av = 0;
3930 
3931 	if (!flags)
3932 		return 0;
3933 	if (flags & LSM_PRLIMIT_WRITE)
3934 		av |= PROCESS__SETRLIMIT;
3935 	if (flags & LSM_PRLIMIT_READ)
3936 		av |= PROCESS__GETRLIMIT;
3937 	return avc_has_perm(&selinux_state,
3938 			    cred_sid(cred), cred_sid(tcred),
3939 			    SECCLASS_PROCESS, av, NULL);
3940 }
3941 
3942 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3943 		struct rlimit *new_rlim)
3944 {
3945 	struct rlimit *old_rlim = p->signal->rlim + resource;
3946 
3947 	/* Control the ability to change the hard limit (whether
3948 	   lowering or raising it), so that the hard limit can
3949 	   later be used as a safe reset point for the soft limit
3950 	   upon context transitions.  See selinux_bprm_committing_creds. */
3951 	if (old_rlim->rlim_max != new_rlim->rlim_max)
3952 		return avc_has_perm(&selinux_state,
3953 				    current_sid(), task_sid(p),
3954 				    SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
3955 
3956 	return 0;
3957 }
3958 
3959 static int selinux_task_setscheduler(struct task_struct *p)
3960 {
3961 	return avc_has_perm(&selinux_state,
3962 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
3963 			    PROCESS__SETSCHED, NULL);
3964 }
3965 
3966 static int selinux_task_getscheduler(struct task_struct *p)
3967 {
3968 	return avc_has_perm(&selinux_state,
3969 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
3970 			    PROCESS__GETSCHED, NULL);
3971 }
3972 
3973 static int selinux_task_movememory(struct task_struct *p)
3974 {
3975 	return avc_has_perm(&selinux_state,
3976 			    current_sid(), task_sid(p), SECCLASS_PROCESS,
3977 			    PROCESS__SETSCHED, NULL);
3978 }
3979 
3980 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
3981 				int sig, const struct cred *cred)
3982 {
3983 	u32 secid;
3984 	u32 perm;
3985 
3986 	if (!sig)
3987 		perm = PROCESS__SIGNULL; /* null signal; existence test */
3988 	else
3989 		perm = signal_to_av(sig);
3990 	if (!cred)
3991 		secid = current_sid();
3992 	else
3993 		secid = cred_sid(cred);
3994 	return avc_has_perm(&selinux_state,
3995 			    secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
3996 }
3997 
3998 static void selinux_task_to_inode(struct task_struct *p,
3999 				  struct inode *inode)
4000 {
4001 	struct inode_security_struct *isec = inode->i_security;
4002 	u32 sid = task_sid(p);
4003 
4004 	spin_lock(&isec->lock);
4005 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
4006 	isec->sid = sid;
4007 	isec->initialized = LABEL_INITIALIZED;
4008 	spin_unlock(&isec->lock);
4009 }
4010 
4011 /* Returns error only if unable to parse addresses */
4012 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4013 			struct common_audit_data *ad, u8 *proto)
4014 {
4015 	int offset, ihlen, ret = -EINVAL;
4016 	struct iphdr _iph, *ih;
4017 
4018 	offset = skb_network_offset(skb);
4019 	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4020 	if (ih == NULL)
4021 		goto out;
4022 
4023 	ihlen = ih->ihl * 4;
4024 	if (ihlen < sizeof(_iph))
4025 		goto out;
4026 
4027 	ad->u.net->v4info.saddr = ih->saddr;
4028 	ad->u.net->v4info.daddr = ih->daddr;
4029 	ret = 0;
4030 
4031 	if (proto)
4032 		*proto = ih->protocol;
4033 
4034 	switch (ih->protocol) {
4035 	case IPPROTO_TCP: {
4036 		struct tcphdr _tcph, *th;
4037 
4038 		if (ntohs(ih->frag_off) & IP_OFFSET)
4039 			break;
4040 
4041 		offset += ihlen;
4042 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4043 		if (th == NULL)
4044 			break;
4045 
4046 		ad->u.net->sport = th->source;
4047 		ad->u.net->dport = th->dest;
4048 		break;
4049 	}
4050 
4051 	case IPPROTO_UDP: {
4052 		struct udphdr _udph, *uh;
4053 
4054 		if (ntohs(ih->frag_off) & IP_OFFSET)
4055 			break;
4056 
4057 		offset += ihlen;
4058 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4059 		if (uh == NULL)
4060 			break;
4061 
4062 		ad->u.net->sport = uh->source;
4063 		ad->u.net->dport = uh->dest;
4064 		break;
4065 	}
4066 
4067 	case IPPROTO_DCCP: {
4068 		struct dccp_hdr _dccph, *dh;
4069 
4070 		if (ntohs(ih->frag_off) & IP_OFFSET)
4071 			break;
4072 
4073 		offset += ihlen;
4074 		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4075 		if (dh == NULL)
4076 			break;
4077 
4078 		ad->u.net->sport = dh->dccph_sport;
4079 		ad->u.net->dport = dh->dccph_dport;
4080 		break;
4081 	}
4082 
4083 #if IS_ENABLED(CONFIG_IP_SCTP)
4084 	case IPPROTO_SCTP: {
4085 		struct sctphdr _sctph, *sh;
4086 
4087 		if (ntohs(ih->frag_off) & IP_OFFSET)
4088 			break;
4089 
4090 		offset += ihlen;
4091 		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4092 		if (sh == NULL)
4093 			break;
4094 
4095 		ad->u.net->sport = sh->source;
4096 		ad->u.net->dport = sh->dest;
4097 		break;
4098 	}
4099 #endif
4100 	default:
4101 		break;
4102 	}
4103 out:
4104 	return ret;
4105 }
4106 
4107 #if IS_ENABLED(CONFIG_IPV6)
4108 
4109 /* Returns error only if unable to parse addresses */
4110 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4111 			struct common_audit_data *ad, u8 *proto)
4112 {
4113 	u8 nexthdr;
4114 	int ret = -EINVAL, offset;
4115 	struct ipv6hdr _ipv6h, *ip6;
4116 	__be16 frag_off;
4117 
4118 	offset = skb_network_offset(skb);
4119 	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4120 	if (ip6 == NULL)
4121 		goto out;
4122 
4123 	ad->u.net->v6info.saddr = ip6->saddr;
4124 	ad->u.net->v6info.daddr = ip6->daddr;
4125 	ret = 0;
4126 
4127 	nexthdr = ip6->nexthdr;
4128 	offset += sizeof(_ipv6h);
4129 	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4130 	if (offset < 0)
4131 		goto out;
4132 
4133 	if (proto)
4134 		*proto = nexthdr;
4135 
4136 	switch (nexthdr) {
4137 	case IPPROTO_TCP: {
4138 		struct tcphdr _tcph, *th;
4139 
4140 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4141 		if (th == NULL)
4142 			break;
4143 
4144 		ad->u.net->sport = th->source;
4145 		ad->u.net->dport = th->dest;
4146 		break;
4147 	}
4148 
4149 	case IPPROTO_UDP: {
4150 		struct udphdr _udph, *uh;
4151 
4152 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4153 		if (uh == NULL)
4154 			break;
4155 
4156 		ad->u.net->sport = uh->source;
4157 		ad->u.net->dport = uh->dest;
4158 		break;
4159 	}
4160 
4161 	case IPPROTO_DCCP: {
4162 		struct dccp_hdr _dccph, *dh;
4163 
4164 		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4165 		if (dh == NULL)
4166 			break;
4167 
4168 		ad->u.net->sport = dh->dccph_sport;
4169 		ad->u.net->dport = dh->dccph_dport;
4170 		break;
4171 	}
4172 
4173 #if IS_ENABLED(CONFIG_IP_SCTP)
4174 	case IPPROTO_SCTP: {
4175 		struct sctphdr _sctph, *sh;
4176 
4177 		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4178 		if (sh == NULL)
4179 			break;
4180 
4181 		ad->u.net->sport = sh->source;
4182 		ad->u.net->dport = sh->dest;
4183 		break;
4184 	}
4185 #endif
4186 	/* includes fragments */
4187 	default:
4188 		break;
4189 	}
4190 out:
4191 	return ret;
4192 }
4193 
4194 #endif /* IPV6 */
4195 
4196 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4197 			     char **_addrp, int src, u8 *proto)
4198 {
4199 	char *addrp;
4200 	int ret;
4201 
4202 	switch (ad->u.net->family) {
4203 	case PF_INET:
4204 		ret = selinux_parse_skb_ipv4(skb, ad, proto);
4205 		if (ret)
4206 			goto parse_error;
4207 		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4208 				       &ad->u.net->v4info.daddr);
4209 		goto okay;
4210 
4211 #if IS_ENABLED(CONFIG_IPV6)
4212 	case PF_INET6:
4213 		ret = selinux_parse_skb_ipv6(skb, ad, proto);
4214 		if (ret)
4215 			goto parse_error;
4216 		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4217 				       &ad->u.net->v6info.daddr);
4218 		goto okay;
4219 #endif	/* IPV6 */
4220 	default:
4221 		addrp = NULL;
4222 		goto okay;
4223 	}
4224 
4225 parse_error:
4226 	pr_warn(
4227 	       "SELinux: failure in selinux_parse_skb(),"
4228 	       " unable to parse packet\n");
4229 	return ret;
4230 
4231 okay:
4232 	if (_addrp)
4233 		*_addrp = addrp;
4234 	return 0;
4235 }
4236 
4237 /**
4238  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4239  * @skb: the packet
4240  * @family: protocol family
4241  * @sid: the packet's peer label SID
4242  *
4243  * Description:
4244  * Check the various different forms of network peer labeling and determine
4245  * the peer label/SID for the packet; most of the magic actually occurs in
4246  * the security server function security_net_peersid_cmp().  The function
4247  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4248  * or -EACCES if @sid is invalid due to inconsistencies with the different
4249  * peer labels.
4250  *
4251  */
4252 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4253 {
4254 	int err;
4255 	u32 xfrm_sid;
4256 	u32 nlbl_sid;
4257 	u32 nlbl_type;
4258 
4259 	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4260 	if (unlikely(err))
4261 		return -EACCES;
4262 	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4263 	if (unlikely(err))
4264 		return -EACCES;
4265 
4266 	err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4267 					   nlbl_type, xfrm_sid, sid);
4268 	if (unlikely(err)) {
4269 		pr_warn(
4270 		       "SELinux: failure in selinux_skb_peerlbl_sid(),"
4271 		       " unable to determine packet's peer label\n");
4272 		return -EACCES;
4273 	}
4274 
4275 	return 0;
4276 }
4277 
4278 /**
4279  * selinux_conn_sid - Determine the child socket label for a connection
4280  * @sk_sid: the parent socket's SID
4281  * @skb_sid: the packet's SID
4282  * @conn_sid: the resulting connection SID
4283  *
4284  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4285  * combined with the MLS information from @skb_sid in order to create
4286  * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
4287  * of @sk_sid.  Returns zero on success, negative values on failure.
4288  *
4289  */
4290 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4291 {
4292 	int err = 0;
4293 
4294 	if (skb_sid != SECSID_NULL)
4295 		err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4296 					    conn_sid);
4297 	else
4298 		*conn_sid = sk_sid;
4299 
4300 	return err;
4301 }
4302 
4303 /* socket security operations */
4304 
4305 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4306 				 u16 secclass, u32 *socksid)
4307 {
4308 	if (tsec->sockcreate_sid > SECSID_NULL) {
4309 		*socksid = tsec->sockcreate_sid;
4310 		return 0;
4311 	}
4312 
4313 	return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4314 				       secclass, NULL, socksid);
4315 }
4316 
4317 static int sock_has_perm(struct sock *sk, u32 perms)
4318 {
4319 	struct sk_security_struct *sksec = sk->sk_security;
4320 	struct common_audit_data ad;
4321 	struct lsm_network_audit net = {0,};
4322 
4323 	if (sksec->sid == SECINITSID_KERNEL)
4324 		return 0;
4325 
4326 	ad.type = LSM_AUDIT_DATA_NET;
4327 	ad.u.net = &net;
4328 	ad.u.net->sk = sk;
4329 
4330 	return avc_has_perm(&selinux_state,
4331 			    current_sid(), sksec->sid, sksec->sclass, perms,
4332 			    &ad);
4333 }
4334 
4335 static int selinux_socket_create(int family, int type,
4336 				 int protocol, int kern)
4337 {
4338 	const struct task_security_struct *tsec = current_security();
4339 	u32 newsid;
4340 	u16 secclass;
4341 	int rc;
4342 
4343 	if (kern)
4344 		return 0;
4345 
4346 	secclass = socket_type_to_security_class(family, type, protocol);
4347 	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4348 	if (rc)
4349 		return rc;
4350 
4351 	return avc_has_perm(&selinux_state,
4352 			    tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4353 }
4354 
4355 static int selinux_socket_post_create(struct socket *sock, int family,
4356 				      int type, int protocol, int kern)
4357 {
4358 	const struct task_security_struct *tsec = current_security();
4359 	struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4360 	struct sk_security_struct *sksec;
4361 	u16 sclass = socket_type_to_security_class(family, type, protocol);
4362 	u32 sid = SECINITSID_KERNEL;
4363 	int err = 0;
4364 
4365 	if (!kern) {
4366 		err = socket_sockcreate_sid(tsec, sclass, &sid);
4367 		if (err)
4368 			return err;
4369 	}
4370 
4371 	isec->sclass = sclass;
4372 	isec->sid = sid;
4373 	isec->initialized = LABEL_INITIALIZED;
4374 
4375 	if (sock->sk) {
4376 		sksec = sock->sk->sk_security;
4377 		sksec->sclass = sclass;
4378 		sksec->sid = sid;
4379 		/* Allows detection of the first association on this socket */
4380 		if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4381 			sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4382 
4383 		err = selinux_netlbl_socket_post_create(sock->sk, family);
4384 	}
4385 
4386 	return err;
4387 }
4388 
4389 static int selinux_socket_socketpair(struct socket *socka,
4390 				     struct socket *sockb)
4391 {
4392 	struct sk_security_struct *sksec_a = socka->sk->sk_security;
4393 	struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4394 
4395 	sksec_a->peer_sid = sksec_b->sid;
4396 	sksec_b->peer_sid = sksec_a->sid;
4397 
4398 	return 0;
4399 }
4400 
4401 /* Range of port numbers used to automatically bind.
4402    Need to determine whether we should perform a name_bind
4403    permission check between the socket and the port number. */
4404 
4405 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4406 {
4407 	struct sock *sk = sock->sk;
4408 	struct sk_security_struct *sksec = sk->sk_security;
4409 	u16 family;
4410 	int err;
4411 
4412 	err = sock_has_perm(sk, SOCKET__BIND);
4413 	if (err)
4414 		goto out;
4415 
4416 	/* If PF_INET or PF_INET6, check name_bind permission for the port. */
4417 	family = sk->sk_family;
4418 	if (family == PF_INET || family == PF_INET6) {
4419 		char *addrp;
4420 		struct common_audit_data ad;
4421 		struct lsm_network_audit net = {0,};
4422 		struct sockaddr_in *addr4 = NULL;
4423 		struct sockaddr_in6 *addr6 = NULL;
4424 		u16 family_sa = address->sa_family;
4425 		unsigned short snum;
4426 		u32 sid, node_perm;
4427 
4428 		/*
4429 		 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4430 		 * that validates multiple binding addresses. Because of this
4431 		 * need to check address->sa_family as it is possible to have
4432 		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4433 		 */
4434 		switch (family_sa) {
4435 		case AF_UNSPEC:
4436 		case AF_INET:
4437 			if (addrlen < sizeof(struct sockaddr_in))
4438 				return -EINVAL;
4439 			addr4 = (struct sockaddr_in *)address;
4440 			if (family_sa == AF_UNSPEC) {
4441 				/* see __inet_bind(), we only want to allow
4442 				 * AF_UNSPEC if the address is INADDR_ANY
4443 				 */
4444 				if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4445 					goto err_af;
4446 				family_sa = AF_INET;
4447 			}
4448 			snum = ntohs(addr4->sin_port);
4449 			addrp = (char *)&addr4->sin_addr.s_addr;
4450 			break;
4451 		case AF_INET6:
4452 			if (addrlen < SIN6_LEN_RFC2133)
4453 				return -EINVAL;
4454 			addr6 = (struct sockaddr_in6 *)address;
4455 			snum = ntohs(addr6->sin6_port);
4456 			addrp = (char *)&addr6->sin6_addr.s6_addr;
4457 			break;
4458 		default:
4459 			goto err_af;
4460 		}
4461 
4462 		ad.type = LSM_AUDIT_DATA_NET;
4463 		ad.u.net = &net;
4464 		ad.u.net->sport = htons(snum);
4465 		ad.u.net->family = family_sa;
4466 
4467 		if (snum) {
4468 			int low, high;
4469 
4470 			inet_get_local_port_range(sock_net(sk), &low, &high);
4471 
4472 			if (snum < max(inet_prot_sock(sock_net(sk)), low) ||
4473 			    snum > high) {
4474 				err = sel_netport_sid(sk->sk_protocol,
4475 						      snum, &sid);
4476 				if (err)
4477 					goto out;
4478 				err = avc_has_perm(&selinux_state,
4479 						   sksec->sid, sid,
4480 						   sksec->sclass,
4481 						   SOCKET__NAME_BIND, &ad);
4482 				if (err)
4483 					goto out;
4484 			}
4485 		}
4486 
4487 		switch (sksec->sclass) {
4488 		case SECCLASS_TCP_SOCKET:
4489 			node_perm = TCP_SOCKET__NODE_BIND;
4490 			break;
4491 
4492 		case SECCLASS_UDP_SOCKET:
4493 			node_perm = UDP_SOCKET__NODE_BIND;
4494 			break;
4495 
4496 		case SECCLASS_DCCP_SOCKET:
4497 			node_perm = DCCP_SOCKET__NODE_BIND;
4498 			break;
4499 
4500 		case SECCLASS_SCTP_SOCKET:
4501 			node_perm = SCTP_SOCKET__NODE_BIND;
4502 			break;
4503 
4504 		default:
4505 			node_perm = RAWIP_SOCKET__NODE_BIND;
4506 			break;
4507 		}
4508 
4509 		err = sel_netnode_sid(addrp, family_sa, &sid);
4510 		if (err)
4511 			goto out;
4512 
4513 		if (family_sa == AF_INET)
4514 			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4515 		else
4516 			ad.u.net->v6info.saddr = addr6->sin6_addr;
4517 
4518 		err = avc_has_perm(&selinux_state,
4519 				   sksec->sid, sid,
4520 				   sksec->sclass, node_perm, &ad);
4521 		if (err)
4522 			goto out;
4523 	}
4524 out:
4525 	return err;
4526 err_af:
4527 	/* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4528 	if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4529 		return -EINVAL;
4530 	return -EAFNOSUPPORT;
4531 }
4532 
4533 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4534  * and sctp_sendmsg(3) as described in Documentation/security/LSM-sctp.rst
4535  */
4536 static int selinux_socket_connect_helper(struct socket *sock,
4537 					 struct sockaddr *address, int addrlen)
4538 {
4539 	struct sock *sk = sock->sk;
4540 	struct sk_security_struct *sksec = sk->sk_security;
4541 	int err;
4542 
4543 	err = sock_has_perm(sk, SOCKET__CONNECT);
4544 	if (err)
4545 		return err;
4546 
4547 	/*
4548 	 * If a TCP, DCCP or SCTP socket, check name_connect permission
4549 	 * for the port.
4550 	 */
4551 	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4552 	    sksec->sclass == SECCLASS_DCCP_SOCKET ||
4553 	    sksec->sclass == SECCLASS_SCTP_SOCKET) {
4554 		struct common_audit_data ad;
4555 		struct lsm_network_audit net = {0,};
4556 		struct sockaddr_in *addr4 = NULL;
4557 		struct sockaddr_in6 *addr6 = NULL;
4558 		unsigned short snum;
4559 		u32 sid, perm;
4560 
4561 		/* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4562 		 * that validates multiple connect addresses. Because of this
4563 		 * need to check address->sa_family as it is possible to have
4564 		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4565 		 */
4566 		switch (address->sa_family) {
4567 		case AF_INET:
4568 			addr4 = (struct sockaddr_in *)address;
4569 			if (addrlen < sizeof(struct sockaddr_in))
4570 				return -EINVAL;
4571 			snum = ntohs(addr4->sin_port);
4572 			break;
4573 		case AF_INET6:
4574 			addr6 = (struct sockaddr_in6 *)address;
4575 			if (addrlen < SIN6_LEN_RFC2133)
4576 				return -EINVAL;
4577 			snum = ntohs(addr6->sin6_port);
4578 			break;
4579 		default:
4580 			/* Note that SCTP services expect -EINVAL, whereas
4581 			 * others expect -EAFNOSUPPORT.
4582 			 */
4583 			if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4584 				return -EINVAL;
4585 			else
4586 				return -EAFNOSUPPORT;
4587 		}
4588 
4589 		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4590 		if (err)
4591 			return err;
4592 
4593 		switch (sksec->sclass) {
4594 		case SECCLASS_TCP_SOCKET:
4595 			perm = TCP_SOCKET__NAME_CONNECT;
4596 			break;
4597 		case SECCLASS_DCCP_SOCKET:
4598 			perm = DCCP_SOCKET__NAME_CONNECT;
4599 			break;
4600 		case SECCLASS_SCTP_SOCKET:
4601 			perm = SCTP_SOCKET__NAME_CONNECT;
4602 			break;
4603 		}
4604 
4605 		ad.type = LSM_AUDIT_DATA_NET;
4606 		ad.u.net = &net;
4607 		ad.u.net->dport = htons(snum);
4608 		ad.u.net->family = address->sa_family;
4609 		err = avc_has_perm(&selinux_state,
4610 				   sksec->sid, sid, sksec->sclass, perm, &ad);
4611 		if (err)
4612 			return err;
4613 	}
4614 
4615 	return 0;
4616 }
4617 
4618 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4619 static int selinux_socket_connect(struct socket *sock,
4620 				  struct sockaddr *address, int addrlen)
4621 {
4622 	int err;
4623 	struct sock *sk = sock->sk;
4624 
4625 	err = selinux_socket_connect_helper(sock, address, addrlen);
4626 	if (err)
4627 		return err;
4628 
4629 	return selinux_netlbl_socket_connect(sk, address);
4630 }
4631 
4632 static int selinux_socket_listen(struct socket *sock, int backlog)
4633 {
4634 	return sock_has_perm(sock->sk, SOCKET__LISTEN);
4635 }
4636 
4637 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4638 {
4639 	int err;
4640 	struct inode_security_struct *isec;
4641 	struct inode_security_struct *newisec;
4642 	u16 sclass;
4643 	u32 sid;
4644 
4645 	err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4646 	if (err)
4647 		return err;
4648 
4649 	isec = inode_security_novalidate(SOCK_INODE(sock));
4650 	spin_lock(&isec->lock);
4651 	sclass = isec->sclass;
4652 	sid = isec->sid;
4653 	spin_unlock(&isec->lock);
4654 
4655 	newisec = inode_security_novalidate(SOCK_INODE(newsock));
4656 	newisec->sclass = sclass;
4657 	newisec->sid = sid;
4658 	newisec->initialized = LABEL_INITIALIZED;
4659 
4660 	return 0;
4661 }
4662 
4663 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4664 				  int size)
4665 {
4666 	return sock_has_perm(sock->sk, SOCKET__WRITE);
4667 }
4668 
4669 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4670 				  int size, int flags)
4671 {
4672 	return sock_has_perm(sock->sk, SOCKET__READ);
4673 }
4674 
4675 static int selinux_socket_getsockname(struct socket *sock)
4676 {
4677 	return sock_has_perm(sock->sk, SOCKET__GETATTR);
4678 }
4679 
4680 static int selinux_socket_getpeername(struct socket *sock)
4681 {
4682 	return sock_has_perm(sock->sk, SOCKET__GETATTR);
4683 }
4684 
4685 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4686 {
4687 	int err;
4688 
4689 	err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4690 	if (err)
4691 		return err;
4692 
4693 	return selinux_netlbl_socket_setsockopt(sock, level, optname);
4694 }
4695 
4696 static int selinux_socket_getsockopt(struct socket *sock, int level,
4697 				     int optname)
4698 {
4699 	return sock_has_perm(sock->sk, SOCKET__GETOPT);
4700 }
4701 
4702 static int selinux_socket_shutdown(struct socket *sock, int how)
4703 {
4704 	return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4705 }
4706 
4707 static int selinux_socket_unix_stream_connect(struct sock *sock,
4708 					      struct sock *other,
4709 					      struct sock *newsk)
4710 {
4711 	struct sk_security_struct *sksec_sock = sock->sk_security;
4712 	struct sk_security_struct *sksec_other = other->sk_security;
4713 	struct sk_security_struct *sksec_new = newsk->sk_security;
4714 	struct common_audit_data ad;
4715 	struct lsm_network_audit net = {0,};
4716 	int err;
4717 
4718 	ad.type = LSM_AUDIT_DATA_NET;
4719 	ad.u.net = &net;
4720 	ad.u.net->sk = other;
4721 
4722 	err = avc_has_perm(&selinux_state,
4723 			   sksec_sock->sid, sksec_other->sid,
4724 			   sksec_other->sclass,
4725 			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4726 	if (err)
4727 		return err;
4728 
4729 	/* server child socket */
4730 	sksec_new->peer_sid = sksec_sock->sid;
4731 	err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
4732 				    sksec_sock->sid, &sksec_new->sid);
4733 	if (err)
4734 		return err;
4735 
4736 	/* connecting socket */
4737 	sksec_sock->peer_sid = sksec_new->sid;
4738 
4739 	return 0;
4740 }
4741 
4742 static int selinux_socket_unix_may_send(struct socket *sock,
4743 					struct socket *other)
4744 {
4745 	struct sk_security_struct *ssec = sock->sk->sk_security;
4746 	struct sk_security_struct *osec = other->sk->sk_security;
4747 	struct common_audit_data ad;
4748 	struct lsm_network_audit net = {0,};
4749 
4750 	ad.type = LSM_AUDIT_DATA_NET;
4751 	ad.u.net = &net;
4752 	ad.u.net->sk = other->sk;
4753 
4754 	return avc_has_perm(&selinux_state,
4755 			    ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4756 			    &ad);
4757 }
4758 
4759 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4760 				    char *addrp, u16 family, u32 peer_sid,
4761 				    struct common_audit_data *ad)
4762 {
4763 	int err;
4764 	u32 if_sid;
4765 	u32 node_sid;
4766 
4767 	err = sel_netif_sid(ns, ifindex, &if_sid);
4768 	if (err)
4769 		return err;
4770 	err = avc_has_perm(&selinux_state,
4771 			   peer_sid, if_sid,
4772 			   SECCLASS_NETIF, NETIF__INGRESS, ad);
4773 	if (err)
4774 		return err;
4775 
4776 	err = sel_netnode_sid(addrp, family, &node_sid);
4777 	if (err)
4778 		return err;
4779 	return avc_has_perm(&selinux_state,
4780 			    peer_sid, node_sid,
4781 			    SECCLASS_NODE, NODE__RECVFROM, ad);
4782 }
4783 
4784 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4785 				       u16 family)
4786 {
4787 	int err = 0;
4788 	struct sk_security_struct *sksec = sk->sk_security;
4789 	u32 sk_sid = sksec->sid;
4790 	struct common_audit_data ad;
4791 	struct lsm_network_audit net = {0,};
4792 	char *addrp;
4793 
4794 	ad.type = LSM_AUDIT_DATA_NET;
4795 	ad.u.net = &net;
4796 	ad.u.net->netif = skb->skb_iif;
4797 	ad.u.net->family = family;
4798 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4799 	if (err)
4800 		return err;
4801 
4802 	if (selinux_secmark_enabled()) {
4803 		err = avc_has_perm(&selinux_state,
4804 				   sk_sid, skb->secmark, SECCLASS_PACKET,
4805 				   PACKET__RECV, &ad);
4806 		if (err)
4807 			return err;
4808 	}
4809 
4810 	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4811 	if (err)
4812 		return err;
4813 	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4814 
4815 	return err;
4816 }
4817 
4818 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4819 {
4820 	int err;
4821 	struct sk_security_struct *sksec = sk->sk_security;
4822 	u16 family = sk->sk_family;
4823 	u32 sk_sid = sksec->sid;
4824 	struct common_audit_data ad;
4825 	struct lsm_network_audit net = {0,};
4826 	char *addrp;
4827 	u8 secmark_active;
4828 	u8 peerlbl_active;
4829 
4830 	if (family != PF_INET && family != PF_INET6)
4831 		return 0;
4832 
4833 	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
4834 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4835 		family = PF_INET;
4836 
4837 	/* If any sort of compatibility mode is enabled then handoff processing
4838 	 * to the selinux_sock_rcv_skb_compat() function to deal with the
4839 	 * special handling.  We do this in an attempt to keep this function
4840 	 * as fast and as clean as possible. */
4841 	if (!selinux_policycap_netpeer())
4842 		return selinux_sock_rcv_skb_compat(sk, skb, family);
4843 
4844 	secmark_active = selinux_secmark_enabled();
4845 	peerlbl_active = selinux_peerlbl_enabled();
4846 	if (!secmark_active && !peerlbl_active)
4847 		return 0;
4848 
4849 	ad.type = LSM_AUDIT_DATA_NET;
4850 	ad.u.net = &net;
4851 	ad.u.net->netif = skb->skb_iif;
4852 	ad.u.net->family = family;
4853 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4854 	if (err)
4855 		return err;
4856 
4857 	if (peerlbl_active) {
4858 		u32 peer_sid;
4859 
4860 		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4861 		if (err)
4862 			return err;
4863 		err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
4864 					       addrp, family, peer_sid, &ad);
4865 		if (err) {
4866 			selinux_netlbl_err(skb, family, err, 0);
4867 			return err;
4868 		}
4869 		err = avc_has_perm(&selinux_state,
4870 				   sk_sid, peer_sid, SECCLASS_PEER,
4871 				   PEER__RECV, &ad);
4872 		if (err) {
4873 			selinux_netlbl_err(skb, family, err, 0);
4874 			return err;
4875 		}
4876 	}
4877 
4878 	if (secmark_active) {
4879 		err = avc_has_perm(&selinux_state,
4880 				   sk_sid, skb->secmark, SECCLASS_PACKET,
4881 				   PACKET__RECV, &ad);
4882 		if (err)
4883 			return err;
4884 	}
4885 
4886 	return err;
4887 }
4888 
4889 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4890 					    int __user *optlen, unsigned len)
4891 {
4892 	int err = 0;
4893 	char *scontext;
4894 	u32 scontext_len;
4895 	struct sk_security_struct *sksec = sock->sk->sk_security;
4896 	u32 peer_sid = SECSID_NULL;
4897 
4898 	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4899 	    sksec->sclass == SECCLASS_TCP_SOCKET ||
4900 	    sksec->sclass == SECCLASS_SCTP_SOCKET)
4901 		peer_sid = sksec->peer_sid;
4902 	if (peer_sid == SECSID_NULL)
4903 		return -ENOPROTOOPT;
4904 
4905 	err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
4906 				      &scontext_len);
4907 	if (err)
4908 		return err;
4909 
4910 	if (scontext_len > len) {
4911 		err = -ERANGE;
4912 		goto out_len;
4913 	}
4914 
4915 	if (copy_to_user(optval, scontext, scontext_len))
4916 		err = -EFAULT;
4917 
4918 out_len:
4919 	if (put_user(scontext_len, optlen))
4920 		err = -EFAULT;
4921 	kfree(scontext);
4922 	return err;
4923 }
4924 
4925 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4926 {
4927 	u32 peer_secid = SECSID_NULL;
4928 	u16 family;
4929 	struct inode_security_struct *isec;
4930 
4931 	if (skb && skb->protocol == htons(ETH_P_IP))
4932 		family = PF_INET;
4933 	else if (skb && skb->protocol == htons(ETH_P_IPV6))
4934 		family = PF_INET6;
4935 	else if (sock)
4936 		family = sock->sk->sk_family;
4937 	else
4938 		goto out;
4939 
4940 	if (sock && family == PF_UNIX) {
4941 		isec = inode_security_novalidate(SOCK_INODE(sock));
4942 		peer_secid = isec->sid;
4943 	} else if (skb)
4944 		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4945 
4946 out:
4947 	*secid = peer_secid;
4948 	if (peer_secid == SECSID_NULL)
4949 		return -EINVAL;
4950 	return 0;
4951 }
4952 
4953 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4954 {
4955 	struct sk_security_struct *sksec;
4956 
4957 	sksec = kzalloc(sizeof(*sksec), priority);
4958 	if (!sksec)
4959 		return -ENOMEM;
4960 
4961 	sksec->peer_sid = SECINITSID_UNLABELED;
4962 	sksec->sid = SECINITSID_UNLABELED;
4963 	sksec->sclass = SECCLASS_SOCKET;
4964 	selinux_netlbl_sk_security_reset(sksec);
4965 	sk->sk_security = sksec;
4966 
4967 	return 0;
4968 }
4969 
4970 static void selinux_sk_free_security(struct sock *sk)
4971 {
4972 	struct sk_security_struct *sksec = sk->sk_security;
4973 
4974 	sk->sk_security = NULL;
4975 	selinux_netlbl_sk_security_free(sksec);
4976 	kfree(sksec);
4977 }
4978 
4979 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4980 {
4981 	struct sk_security_struct *sksec = sk->sk_security;
4982 	struct sk_security_struct *newsksec = newsk->sk_security;
4983 
4984 	newsksec->sid = sksec->sid;
4985 	newsksec->peer_sid = sksec->peer_sid;
4986 	newsksec->sclass = sksec->sclass;
4987 
4988 	selinux_netlbl_sk_security_reset(newsksec);
4989 }
4990 
4991 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4992 {
4993 	if (!sk)
4994 		*secid = SECINITSID_ANY_SOCKET;
4995 	else {
4996 		struct sk_security_struct *sksec = sk->sk_security;
4997 
4998 		*secid = sksec->sid;
4999 	}
5000 }
5001 
5002 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5003 {
5004 	struct inode_security_struct *isec =
5005 		inode_security_novalidate(SOCK_INODE(parent));
5006 	struct sk_security_struct *sksec = sk->sk_security;
5007 
5008 	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5009 	    sk->sk_family == PF_UNIX)
5010 		isec->sid = sksec->sid;
5011 	sksec->sclass = isec->sclass;
5012 }
5013 
5014 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5015  * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5016  * already present).
5017  */
5018 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5019 				      struct sk_buff *skb)
5020 {
5021 	struct sk_security_struct *sksec = ep->base.sk->sk_security;
5022 	struct common_audit_data ad;
5023 	struct lsm_network_audit net = {0,};
5024 	u8 peerlbl_active;
5025 	u32 peer_sid = SECINITSID_UNLABELED;
5026 	u32 conn_sid;
5027 	int err = 0;
5028 
5029 	if (!selinux_policycap_extsockclass())
5030 		return 0;
5031 
5032 	peerlbl_active = selinux_peerlbl_enabled();
5033 
5034 	if (peerlbl_active) {
5035 		/* This will return peer_sid = SECSID_NULL if there are
5036 		 * no peer labels, see security_net_peersid_resolve().
5037 		 */
5038 		err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5039 					      &peer_sid);
5040 		if (err)
5041 			return err;
5042 
5043 		if (peer_sid == SECSID_NULL)
5044 			peer_sid = SECINITSID_UNLABELED;
5045 	}
5046 
5047 	if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5048 		sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5049 
5050 		/* Here as first association on socket. As the peer SID
5051 		 * was allowed by peer recv (and the netif/node checks),
5052 		 * then it is approved by policy and used as the primary
5053 		 * peer SID for getpeercon(3).
5054 		 */
5055 		sksec->peer_sid = peer_sid;
5056 	} else if  (sksec->peer_sid != peer_sid) {
5057 		/* Other association peer SIDs are checked to enforce
5058 		 * consistency among the peer SIDs.
5059 		 */
5060 		ad.type = LSM_AUDIT_DATA_NET;
5061 		ad.u.net = &net;
5062 		ad.u.net->sk = ep->base.sk;
5063 		err = avc_has_perm(&selinux_state,
5064 				   sksec->peer_sid, peer_sid, sksec->sclass,
5065 				   SCTP_SOCKET__ASSOCIATION, &ad);
5066 		if (err)
5067 			return err;
5068 	}
5069 
5070 	/* Compute the MLS component for the connection and store
5071 	 * the information in ep. This will be used by SCTP TCP type
5072 	 * sockets and peeled off connections as they cause a new
5073 	 * socket to be generated. selinux_sctp_sk_clone() will then
5074 	 * plug this into the new socket.
5075 	 */
5076 	err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5077 	if (err)
5078 		return err;
5079 
5080 	ep->secid = conn_sid;
5081 	ep->peer_secid = peer_sid;
5082 
5083 	/* Set any NetLabel labels including CIPSO/CALIPSO options. */
5084 	return selinux_netlbl_sctp_assoc_request(ep, skb);
5085 }
5086 
5087 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5088  * based on their @optname.
5089  */
5090 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5091 				     struct sockaddr *address,
5092 				     int addrlen)
5093 {
5094 	int len, err = 0, walk_size = 0;
5095 	void *addr_buf;
5096 	struct sockaddr *addr;
5097 	struct socket *sock;
5098 
5099 	if (!selinux_policycap_extsockclass())
5100 		return 0;
5101 
5102 	/* Process one or more addresses that may be IPv4 or IPv6 */
5103 	sock = sk->sk_socket;
5104 	addr_buf = address;
5105 
5106 	while (walk_size < addrlen) {
5107 		if (walk_size + sizeof(sa_family_t) > addrlen)
5108 			return -EINVAL;
5109 
5110 		addr = addr_buf;
5111 		switch (addr->sa_family) {
5112 		case AF_UNSPEC:
5113 		case AF_INET:
5114 			len = sizeof(struct sockaddr_in);
5115 			break;
5116 		case AF_INET6:
5117 			len = sizeof(struct sockaddr_in6);
5118 			break;
5119 		default:
5120 			return -EINVAL;
5121 		}
5122 
5123 		err = -EINVAL;
5124 		switch (optname) {
5125 		/* Bind checks */
5126 		case SCTP_PRIMARY_ADDR:
5127 		case SCTP_SET_PEER_PRIMARY_ADDR:
5128 		case SCTP_SOCKOPT_BINDX_ADD:
5129 			err = selinux_socket_bind(sock, addr, len);
5130 			break;
5131 		/* Connect checks */
5132 		case SCTP_SOCKOPT_CONNECTX:
5133 		case SCTP_PARAM_SET_PRIMARY:
5134 		case SCTP_PARAM_ADD_IP:
5135 		case SCTP_SENDMSG_CONNECT:
5136 			err = selinux_socket_connect_helper(sock, addr, len);
5137 			if (err)
5138 				return err;
5139 
5140 			/* As selinux_sctp_bind_connect() is called by the
5141 			 * SCTP protocol layer, the socket is already locked,
5142 			 * therefore selinux_netlbl_socket_connect_locked() is
5143 			 * is called here. The situations handled are:
5144 			 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5145 			 * whenever a new IP address is added or when a new
5146 			 * primary address is selected.
5147 			 * Note that an SCTP connect(2) call happens before
5148 			 * the SCTP protocol layer and is handled via
5149 			 * selinux_socket_connect().
5150 			 */
5151 			err = selinux_netlbl_socket_connect_locked(sk, addr);
5152 			break;
5153 		}
5154 
5155 		if (err)
5156 			return err;
5157 
5158 		addr_buf += len;
5159 		walk_size += len;
5160 	}
5161 
5162 	return 0;
5163 }
5164 
5165 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5166 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5167 				  struct sock *newsk)
5168 {
5169 	struct sk_security_struct *sksec = sk->sk_security;
5170 	struct sk_security_struct *newsksec = newsk->sk_security;
5171 
5172 	/* If policy does not support SECCLASS_SCTP_SOCKET then call
5173 	 * the non-sctp clone version.
5174 	 */
5175 	if (!selinux_policycap_extsockclass())
5176 		return selinux_sk_clone_security(sk, newsk);
5177 
5178 	newsksec->sid = ep->secid;
5179 	newsksec->peer_sid = ep->peer_secid;
5180 	newsksec->sclass = sksec->sclass;
5181 	selinux_netlbl_sctp_sk_clone(sk, newsk);
5182 }
5183 
5184 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
5185 				     struct request_sock *req)
5186 {
5187 	struct sk_security_struct *sksec = sk->sk_security;
5188 	int err;
5189 	u16 family = req->rsk_ops->family;
5190 	u32 connsid;
5191 	u32 peersid;
5192 
5193 	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5194 	if (err)
5195 		return err;
5196 	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5197 	if (err)
5198 		return err;
5199 	req->secid = connsid;
5200 	req->peer_secid = peersid;
5201 
5202 	return selinux_netlbl_inet_conn_request(req, family);
5203 }
5204 
5205 static void selinux_inet_csk_clone(struct sock *newsk,
5206 				   const struct request_sock *req)
5207 {
5208 	struct sk_security_struct *newsksec = newsk->sk_security;
5209 
5210 	newsksec->sid = req->secid;
5211 	newsksec->peer_sid = req->peer_secid;
5212 	/* NOTE: Ideally, we should also get the isec->sid for the
5213 	   new socket in sync, but we don't have the isec available yet.
5214 	   So we will wait until sock_graft to do it, by which
5215 	   time it will have been created and available. */
5216 
5217 	/* We don't need to take any sort of lock here as we are the only
5218 	 * thread with access to newsksec */
5219 	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5220 }
5221 
5222 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5223 {
5224 	u16 family = sk->sk_family;
5225 	struct sk_security_struct *sksec = sk->sk_security;
5226 
5227 	/* handle mapped IPv4 packets arriving via IPv6 sockets */
5228 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5229 		family = PF_INET;
5230 
5231 	selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5232 }
5233 
5234 static int selinux_secmark_relabel_packet(u32 sid)
5235 {
5236 	const struct task_security_struct *__tsec;
5237 	u32 tsid;
5238 
5239 	__tsec = current_security();
5240 	tsid = __tsec->sid;
5241 
5242 	return avc_has_perm(&selinux_state,
5243 			    tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5244 			    NULL);
5245 }
5246 
5247 static void selinux_secmark_refcount_inc(void)
5248 {
5249 	atomic_inc(&selinux_secmark_refcount);
5250 }
5251 
5252 static void selinux_secmark_refcount_dec(void)
5253 {
5254 	atomic_dec(&selinux_secmark_refcount);
5255 }
5256 
5257 static void selinux_req_classify_flow(const struct request_sock *req,
5258 				      struct flowi *fl)
5259 {
5260 	fl->flowi_secid = req->secid;
5261 }
5262 
5263 static int selinux_tun_dev_alloc_security(void **security)
5264 {
5265 	struct tun_security_struct *tunsec;
5266 
5267 	tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5268 	if (!tunsec)
5269 		return -ENOMEM;
5270 	tunsec->sid = current_sid();
5271 
5272 	*security = tunsec;
5273 	return 0;
5274 }
5275 
5276 static void selinux_tun_dev_free_security(void *security)
5277 {
5278 	kfree(security);
5279 }
5280 
5281 static int selinux_tun_dev_create(void)
5282 {
5283 	u32 sid = current_sid();
5284 
5285 	/* we aren't taking into account the "sockcreate" SID since the socket
5286 	 * that is being created here is not a socket in the traditional sense,
5287 	 * instead it is a private sock, accessible only to the kernel, and
5288 	 * representing a wide range of network traffic spanning multiple
5289 	 * connections unlike traditional sockets - check the TUN driver to
5290 	 * get a better understanding of why this socket is special */
5291 
5292 	return avc_has_perm(&selinux_state,
5293 			    sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5294 			    NULL);
5295 }
5296 
5297 static int selinux_tun_dev_attach_queue(void *security)
5298 {
5299 	struct tun_security_struct *tunsec = security;
5300 
5301 	return avc_has_perm(&selinux_state,
5302 			    current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5303 			    TUN_SOCKET__ATTACH_QUEUE, NULL);
5304 }
5305 
5306 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5307 {
5308 	struct tun_security_struct *tunsec = security;
5309 	struct sk_security_struct *sksec = sk->sk_security;
5310 
5311 	/* we don't currently perform any NetLabel based labeling here and it
5312 	 * isn't clear that we would want to do so anyway; while we could apply
5313 	 * labeling without the support of the TUN user the resulting labeled
5314 	 * traffic from the other end of the connection would almost certainly
5315 	 * cause confusion to the TUN user that had no idea network labeling
5316 	 * protocols were being used */
5317 
5318 	sksec->sid = tunsec->sid;
5319 	sksec->sclass = SECCLASS_TUN_SOCKET;
5320 
5321 	return 0;
5322 }
5323 
5324 static int selinux_tun_dev_open(void *security)
5325 {
5326 	struct tun_security_struct *tunsec = security;
5327 	u32 sid = current_sid();
5328 	int err;
5329 
5330 	err = avc_has_perm(&selinux_state,
5331 			   sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5332 			   TUN_SOCKET__RELABELFROM, NULL);
5333 	if (err)
5334 		return err;
5335 	err = avc_has_perm(&selinux_state,
5336 			   sid, sid, SECCLASS_TUN_SOCKET,
5337 			   TUN_SOCKET__RELABELTO, NULL);
5338 	if (err)
5339 		return err;
5340 	tunsec->sid = sid;
5341 
5342 	return 0;
5343 }
5344 
5345 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
5346 {
5347 	int err = 0;
5348 	u32 perm;
5349 	struct nlmsghdr *nlh;
5350 	struct sk_security_struct *sksec = sk->sk_security;
5351 
5352 	if (skb->len < NLMSG_HDRLEN) {
5353 		err = -EINVAL;
5354 		goto out;
5355 	}
5356 	nlh = nlmsg_hdr(skb);
5357 
5358 	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
5359 	if (err) {
5360 		if (err == -EINVAL) {
5361 			pr_warn_ratelimited("SELinux: unrecognized netlink"
5362 			       " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5363 			       " pig=%d comm=%s\n",
5364 			       sk->sk_protocol, nlh->nlmsg_type,
5365 			       secclass_map[sksec->sclass - 1].name,
5366 			       task_pid_nr(current), current->comm);
5367 			if (!enforcing_enabled(&selinux_state) ||
5368 			    security_get_allow_unknown(&selinux_state))
5369 				err = 0;
5370 		}
5371 
5372 		/* Ignore */
5373 		if (err == -ENOENT)
5374 			err = 0;
5375 		goto out;
5376 	}
5377 
5378 	err = sock_has_perm(sk, perm);
5379 out:
5380 	return err;
5381 }
5382 
5383 #ifdef CONFIG_NETFILTER
5384 
5385 static unsigned int selinux_ip_forward(struct sk_buff *skb,
5386 				       const struct net_device *indev,
5387 				       u16 family)
5388 {
5389 	int err;
5390 	char *addrp;
5391 	u32 peer_sid;
5392 	struct common_audit_data ad;
5393 	struct lsm_network_audit net = {0,};
5394 	u8 secmark_active;
5395 	u8 netlbl_active;
5396 	u8 peerlbl_active;
5397 
5398 	if (!selinux_policycap_netpeer())
5399 		return NF_ACCEPT;
5400 
5401 	secmark_active = selinux_secmark_enabled();
5402 	netlbl_active = netlbl_enabled();
5403 	peerlbl_active = selinux_peerlbl_enabled();
5404 	if (!secmark_active && !peerlbl_active)
5405 		return NF_ACCEPT;
5406 
5407 	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5408 		return NF_DROP;
5409 
5410 	ad.type = LSM_AUDIT_DATA_NET;
5411 	ad.u.net = &net;
5412 	ad.u.net->netif = indev->ifindex;
5413 	ad.u.net->family = family;
5414 	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5415 		return NF_DROP;
5416 
5417 	if (peerlbl_active) {
5418 		err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5419 					       addrp, family, peer_sid, &ad);
5420 		if (err) {
5421 			selinux_netlbl_err(skb, family, err, 1);
5422 			return NF_DROP;
5423 		}
5424 	}
5425 
5426 	if (secmark_active)
5427 		if (avc_has_perm(&selinux_state,
5428 				 peer_sid, skb->secmark,
5429 				 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5430 			return NF_DROP;
5431 
5432 	if (netlbl_active)
5433 		/* we do this in the FORWARD path and not the POST_ROUTING
5434 		 * path because we want to make sure we apply the necessary
5435 		 * labeling before IPsec is applied so we can leverage AH
5436 		 * protection */
5437 		if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5438 			return NF_DROP;
5439 
5440 	return NF_ACCEPT;
5441 }
5442 
5443 static unsigned int selinux_ipv4_forward(void *priv,
5444 					 struct sk_buff *skb,
5445 					 const struct nf_hook_state *state)
5446 {
5447 	return selinux_ip_forward(skb, state->in, PF_INET);
5448 }
5449 
5450 #if IS_ENABLED(CONFIG_IPV6)
5451 static unsigned int selinux_ipv6_forward(void *priv,
5452 					 struct sk_buff *skb,
5453 					 const struct nf_hook_state *state)
5454 {
5455 	return selinux_ip_forward(skb, state->in, PF_INET6);
5456 }
5457 #endif	/* IPV6 */
5458 
5459 static unsigned int selinux_ip_output(struct sk_buff *skb,
5460 				      u16 family)
5461 {
5462 	struct sock *sk;
5463 	u32 sid;
5464 
5465 	if (!netlbl_enabled())
5466 		return NF_ACCEPT;
5467 
5468 	/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5469 	 * because we want to make sure we apply the necessary labeling
5470 	 * before IPsec is applied so we can leverage AH protection */
5471 	sk = skb->sk;
5472 	if (sk) {
5473 		struct sk_security_struct *sksec;
5474 
5475 		if (sk_listener(sk))
5476 			/* if the socket is the listening state then this
5477 			 * packet is a SYN-ACK packet which means it needs to
5478 			 * be labeled based on the connection/request_sock and
5479 			 * not the parent socket.  unfortunately, we can't
5480 			 * lookup the request_sock yet as it isn't queued on
5481 			 * the parent socket until after the SYN-ACK is sent.
5482 			 * the "solution" is to simply pass the packet as-is
5483 			 * as any IP option based labeling should be copied
5484 			 * from the initial connection request (in the IP
5485 			 * layer).  it is far from ideal, but until we get a
5486 			 * security label in the packet itself this is the
5487 			 * best we can do. */
5488 			return NF_ACCEPT;
5489 
5490 		/* standard practice, label using the parent socket */
5491 		sksec = sk->sk_security;
5492 		sid = sksec->sid;
5493 	} else
5494 		sid = SECINITSID_KERNEL;
5495 	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5496 		return NF_DROP;
5497 
5498 	return NF_ACCEPT;
5499 }
5500 
5501 static unsigned int selinux_ipv4_output(void *priv,
5502 					struct sk_buff *skb,
5503 					const struct nf_hook_state *state)
5504 {
5505 	return selinux_ip_output(skb, PF_INET);
5506 }
5507 
5508 #if IS_ENABLED(CONFIG_IPV6)
5509 static unsigned int selinux_ipv6_output(void *priv,
5510 					struct sk_buff *skb,
5511 					const struct nf_hook_state *state)
5512 {
5513 	return selinux_ip_output(skb, PF_INET6);
5514 }
5515 #endif	/* IPV6 */
5516 
5517 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5518 						int ifindex,
5519 						u16 family)
5520 {
5521 	struct sock *sk = skb_to_full_sk(skb);
5522 	struct sk_security_struct *sksec;
5523 	struct common_audit_data ad;
5524 	struct lsm_network_audit net = {0,};
5525 	char *addrp;
5526 	u8 proto;
5527 
5528 	if (sk == NULL)
5529 		return NF_ACCEPT;
5530 	sksec = sk->sk_security;
5531 
5532 	ad.type = LSM_AUDIT_DATA_NET;
5533 	ad.u.net = &net;
5534 	ad.u.net->netif = ifindex;
5535 	ad.u.net->family = family;
5536 	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5537 		return NF_DROP;
5538 
5539 	if (selinux_secmark_enabled())
5540 		if (avc_has_perm(&selinux_state,
5541 				 sksec->sid, skb->secmark,
5542 				 SECCLASS_PACKET, PACKET__SEND, &ad))
5543 			return NF_DROP_ERR(-ECONNREFUSED);
5544 
5545 	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5546 		return NF_DROP_ERR(-ECONNREFUSED);
5547 
5548 	return NF_ACCEPT;
5549 }
5550 
5551 static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5552 					 const struct net_device *outdev,
5553 					 u16 family)
5554 {
5555 	u32 secmark_perm;
5556 	u32 peer_sid;
5557 	int ifindex = outdev->ifindex;
5558 	struct sock *sk;
5559 	struct common_audit_data ad;
5560 	struct lsm_network_audit net = {0,};
5561 	char *addrp;
5562 	u8 secmark_active;
5563 	u8 peerlbl_active;
5564 
5565 	/* If any sort of compatibility mode is enabled then handoff processing
5566 	 * to the selinux_ip_postroute_compat() function to deal with the
5567 	 * special handling.  We do this in an attempt to keep this function
5568 	 * as fast and as clean as possible. */
5569 	if (!selinux_policycap_netpeer())
5570 		return selinux_ip_postroute_compat(skb, ifindex, family);
5571 
5572 	secmark_active = selinux_secmark_enabled();
5573 	peerlbl_active = selinux_peerlbl_enabled();
5574 	if (!secmark_active && !peerlbl_active)
5575 		return NF_ACCEPT;
5576 
5577 	sk = skb_to_full_sk(skb);
5578 
5579 #ifdef CONFIG_XFRM
5580 	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5581 	 * packet transformation so allow the packet to pass without any checks
5582 	 * since we'll have another chance to perform access control checks
5583 	 * when the packet is on it's final way out.
5584 	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5585 	 *       is NULL, in this case go ahead and apply access control.
5586 	 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5587 	 *       TCP listening state we cannot wait until the XFRM processing
5588 	 *       is done as we will miss out on the SA label if we do;
5589 	 *       unfortunately, this means more work, but it is only once per
5590 	 *       connection. */
5591 	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5592 	    !(sk && sk_listener(sk)))
5593 		return NF_ACCEPT;
5594 #endif
5595 
5596 	if (sk == NULL) {
5597 		/* Without an associated socket the packet is either coming
5598 		 * from the kernel or it is being forwarded; check the packet
5599 		 * to determine which and if the packet is being forwarded
5600 		 * query the packet directly to determine the security label. */
5601 		if (skb->skb_iif) {
5602 			secmark_perm = PACKET__FORWARD_OUT;
5603 			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5604 				return NF_DROP;
5605 		} else {
5606 			secmark_perm = PACKET__SEND;
5607 			peer_sid = SECINITSID_KERNEL;
5608 		}
5609 	} else if (sk_listener(sk)) {
5610 		/* Locally generated packet but the associated socket is in the
5611 		 * listening state which means this is a SYN-ACK packet.  In
5612 		 * this particular case the correct security label is assigned
5613 		 * to the connection/request_sock but unfortunately we can't
5614 		 * query the request_sock as it isn't queued on the parent
5615 		 * socket until after the SYN-ACK packet is sent; the only
5616 		 * viable choice is to regenerate the label like we do in
5617 		 * selinux_inet_conn_request().  See also selinux_ip_output()
5618 		 * for similar problems. */
5619 		u32 skb_sid;
5620 		struct sk_security_struct *sksec;
5621 
5622 		sksec = sk->sk_security;
5623 		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5624 			return NF_DROP;
5625 		/* At this point, if the returned skb peerlbl is SECSID_NULL
5626 		 * and the packet has been through at least one XFRM
5627 		 * transformation then we must be dealing with the "final"
5628 		 * form of labeled IPsec packet; since we've already applied
5629 		 * all of our access controls on this packet we can safely
5630 		 * pass the packet. */
5631 		if (skb_sid == SECSID_NULL) {
5632 			switch (family) {
5633 			case PF_INET:
5634 				if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5635 					return NF_ACCEPT;
5636 				break;
5637 			case PF_INET6:
5638 				if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5639 					return NF_ACCEPT;
5640 				break;
5641 			default:
5642 				return NF_DROP_ERR(-ECONNREFUSED);
5643 			}
5644 		}
5645 		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5646 			return NF_DROP;
5647 		secmark_perm = PACKET__SEND;
5648 	} else {
5649 		/* Locally generated packet, fetch the security label from the
5650 		 * associated socket. */
5651 		struct sk_security_struct *sksec = sk->sk_security;
5652 		peer_sid = sksec->sid;
5653 		secmark_perm = PACKET__SEND;
5654 	}
5655 
5656 	ad.type = LSM_AUDIT_DATA_NET;
5657 	ad.u.net = &net;
5658 	ad.u.net->netif = ifindex;
5659 	ad.u.net->family = family;
5660 	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5661 		return NF_DROP;
5662 
5663 	if (secmark_active)
5664 		if (avc_has_perm(&selinux_state,
5665 				 peer_sid, skb->secmark,
5666 				 SECCLASS_PACKET, secmark_perm, &ad))
5667 			return NF_DROP_ERR(-ECONNREFUSED);
5668 
5669 	if (peerlbl_active) {
5670 		u32 if_sid;
5671 		u32 node_sid;
5672 
5673 		if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5674 			return NF_DROP;
5675 		if (avc_has_perm(&selinux_state,
5676 				 peer_sid, if_sid,
5677 				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5678 			return NF_DROP_ERR(-ECONNREFUSED);
5679 
5680 		if (sel_netnode_sid(addrp, family, &node_sid))
5681 			return NF_DROP;
5682 		if (avc_has_perm(&selinux_state,
5683 				 peer_sid, node_sid,
5684 				 SECCLASS_NODE, NODE__SENDTO, &ad))
5685 			return NF_DROP_ERR(-ECONNREFUSED);
5686 	}
5687 
5688 	return NF_ACCEPT;
5689 }
5690 
5691 static unsigned int selinux_ipv4_postroute(void *priv,
5692 					   struct sk_buff *skb,
5693 					   const struct nf_hook_state *state)
5694 {
5695 	return selinux_ip_postroute(skb, state->out, PF_INET);
5696 }
5697 
5698 #if IS_ENABLED(CONFIG_IPV6)
5699 static unsigned int selinux_ipv6_postroute(void *priv,
5700 					   struct sk_buff *skb,
5701 					   const struct nf_hook_state *state)
5702 {
5703 	return selinux_ip_postroute(skb, state->out, PF_INET6);
5704 }
5705 #endif	/* IPV6 */
5706 
5707 #endif	/* CONFIG_NETFILTER */
5708 
5709 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5710 {
5711 	return selinux_nlmsg_perm(sk, skb);
5712 }
5713 
5714 static int ipc_alloc_security(struct kern_ipc_perm *perm,
5715 			      u16 sclass)
5716 {
5717 	struct ipc_security_struct *isec;
5718 
5719 	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5720 	if (!isec)
5721 		return -ENOMEM;
5722 
5723 	isec->sclass = sclass;
5724 	isec->sid = current_sid();
5725 	perm->security = isec;
5726 
5727 	return 0;
5728 }
5729 
5730 static void ipc_free_security(struct kern_ipc_perm *perm)
5731 {
5732 	struct ipc_security_struct *isec = perm->security;
5733 	perm->security = NULL;
5734 	kfree(isec);
5735 }
5736 
5737 static int msg_msg_alloc_security(struct msg_msg *msg)
5738 {
5739 	struct msg_security_struct *msec;
5740 
5741 	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5742 	if (!msec)
5743 		return -ENOMEM;
5744 
5745 	msec->sid = SECINITSID_UNLABELED;
5746 	msg->security = msec;
5747 
5748 	return 0;
5749 }
5750 
5751 static void msg_msg_free_security(struct msg_msg *msg)
5752 {
5753 	struct msg_security_struct *msec = msg->security;
5754 
5755 	msg->security = NULL;
5756 	kfree(msec);
5757 }
5758 
5759 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5760 			u32 perms)
5761 {
5762 	struct ipc_security_struct *isec;
5763 	struct common_audit_data ad;
5764 	u32 sid = current_sid();
5765 
5766 	isec = ipc_perms->security;
5767 
5768 	ad.type = LSM_AUDIT_DATA_IPC;
5769 	ad.u.ipc_id = ipc_perms->key;
5770 
5771 	return avc_has_perm(&selinux_state,
5772 			    sid, isec->sid, isec->sclass, perms, &ad);
5773 }
5774 
5775 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5776 {
5777 	return msg_msg_alloc_security(msg);
5778 }
5779 
5780 static void selinux_msg_msg_free_security(struct msg_msg *msg)
5781 {
5782 	msg_msg_free_security(msg);
5783 }
5784 
5785 /* message queue security operations */
5786 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5787 {
5788 	struct ipc_security_struct *isec;
5789 	struct common_audit_data ad;
5790 	u32 sid = current_sid();
5791 	int rc;
5792 
5793 	rc = ipc_alloc_security(msq, SECCLASS_MSGQ);
5794 	if (rc)
5795 		return rc;
5796 
5797 	isec = msq->security;
5798 
5799 	ad.type = LSM_AUDIT_DATA_IPC;
5800 	ad.u.ipc_id = msq->key;
5801 
5802 	rc = avc_has_perm(&selinux_state,
5803 			  sid, isec->sid, SECCLASS_MSGQ,
5804 			  MSGQ__CREATE, &ad);
5805 	if (rc) {
5806 		ipc_free_security(msq);
5807 		return rc;
5808 	}
5809 	return 0;
5810 }
5811 
5812 static void selinux_msg_queue_free_security(struct kern_ipc_perm *msq)
5813 {
5814 	ipc_free_security(msq);
5815 }
5816 
5817 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
5818 {
5819 	struct ipc_security_struct *isec;
5820 	struct common_audit_data ad;
5821 	u32 sid = current_sid();
5822 
5823 	isec = msq->security;
5824 
5825 	ad.type = LSM_AUDIT_DATA_IPC;
5826 	ad.u.ipc_id = msq->key;
5827 
5828 	return avc_has_perm(&selinux_state,
5829 			    sid, isec->sid, SECCLASS_MSGQ,
5830 			    MSGQ__ASSOCIATE, &ad);
5831 }
5832 
5833 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
5834 {
5835 	int err;
5836 	int perms;
5837 
5838 	switch (cmd) {
5839 	case IPC_INFO:
5840 	case MSG_INFO:
5841 		/* No specific object, just general system-wide information. */
5842 		return avc_has_perm(&selinux_state,
5843 				    current_sid(), SECINITSID_KERNEL,
5844 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
5845 	case IPC_STAT:
5846 	case MSG_STAT:
5847 	case MSG_STAT_ANY:
5848 		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5849 		break;
5850 	case IPC_SET:
5851 		perms = MSGQ__SETATTR;
5852 		break;
5853 	case IPC_RMID:
5854 		perms = MSGQ__DESTROY;
5855 		break;
5856 	default:
5857 		return 0;
5858 	}
5859 
5860 	err = ipc_has_perm(msq, perms);
5861 	return err;
5862 }
5863 
5864 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
5865 {
5866 	struct ipc_security_struct *isec;
5867 	struct msg_security_struct *msec;
5868 	struct common_audit_data ad;
5869 	u32 sid = current_sid();
5870 	int rc;
5871 
5872 	isec = msq->security;
5873 	msec = msg->security;
5874 
5875 	/*
5876 	 * First time through, need to assign label to the message
5877 	 */
5878 	if (msec->sid == SECINITSID_UNLABELED) {
5879 		/*
5880 		 * Compute new sid based on current process and
5881 		 * message queue this message will be stored in
5882 		 */
5883 		rc = security_transition_sid(&selinux_state, sid, isec->sid,
5884 					     SECCLASS_MSG, NULL, &msec->sid);
5885 		if (rc)
5886 			return rc;
5887 	}
5888 
5889 	ad.type = LSM_AUDIT_DATA_IPC;
5890 	ad.u.ipc_id = msq->key;
5891 
5892 	/* Can this process write to the queue? */
5893 	rc = avc_has_perm(&selinux_state,
5894 			  sid, isec->sid, SECCLASS_MSGQ,
5895 			  MSGQ__WRITE, &ad);
5896 	if (!rc)
5897 		/* Can this process send the message */
5898 		rc = avc_has_perm(&selinux_state,
5899 				  sid, msec->sid, SECCLASS_MSG,
5900 				  MSG__SEND, &ad);
5901 	if (!rc)
5902 		/* Can the message be put in the queue? */
5903 		rc = avc_has_perm(&selinux_state,
5904 				  msec->sid, isec->sid, SECCLASS_MSGQ,
5905 				  MSGQ__ENQUEUE, &ad);
5906 
5907 	return rc;
5908 }
5909 
5910 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
5911 				    struct task_struct *target,
5912 				    long type, int mode)
5913 {
5914 	struct ipc_security_struct *isec;
5915 	struct msg_security_struct *msec;
5916 	struct common_audit_data ad;
5917 	u32 sid = task_sid(target);
5918 	int rc;
5919 
5920 	isec = msq->security;
5921 	msec = msg->security;
5922 
5923 	ad.type = LSM_AUDIT_DATA_IPC;
5924 	ad.u.ipc_id = msq->key;
5925 
5926 	rc = avc_has_perm(&selinux_state,
5927 			  sid, isec->sid,
5928 			  SECCLASS_MSGQ, MSGQ__READ, &ad);
5929 	if (!rc)
5930 		rc = avc_has_perm(&selinux_state,
5931 				  sid, msec->sid,
5932 				  SECCLASS_MSG, MSG__RECEIVE, &ad);
5933 	return rc;
5934 }
5935 
5936 /* Shared Memory security operations */
5937 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
5938 {
5939 	struct ipc_security_struct *isec;
5940 	struct common_audit_data ad;
5941 	u32 sid = current_sid();
5942 	int rc;
5943 
5944 	rc = ipc_alloc_security(shp, SECCLASS_SHM);
5945 	if (rc)
5946 		return rc;
5947 
5948 	isec = shp->security;
5949 
5950 	ad.type = LSM_AUDIT_DATA_IPC;
5951 	ad.u.ipc_id = shp->key;
5952 
5953 	rc = avc_has_perm(&selinux_state,
5954 			  sid, isec->sid, SECCLASS_SHM,
5955 			  SHM__CREATE, &ad);
5956 	if (rc) {
5957 		ipc_free_security(shp);
5958 		return rc;
5959 	}
5960 	return 0;
5961 }
5962 
5963 static void selinux_shm_free_security(struct kern_ipc_perm *shp)
5964 {
5965 	ipc_free_security(shp);
5966 }
5967 
5968 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
5969 {
5970 	struct ipc_security_struct *isec;
5971 	struct common_audit_data ad;
5972 	u32 sid = current_sid();
5973 
5974 	isec = shp->security;
5975 
5976 	ad.type = LSM_AUDIT_DATA_IPC;
5977 	ad.u.ipc_id = shp->key;
5978 
5979 	return avc_has_perm(&selinux_state,
5980 			    sid, isec->sid, SECCLASS_SHM,
5981 			    SHM__ASSOCIATE, &ad);
5982 }
5983 
5984 /* Note, at this point, shp is locked down */
5985 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
5986 {
5987 	int perms;
5988 	int err;
5989 
5990 	switch (cmd) {
5991 	case IPC_INFO:
5992 	case SHM_INFO:
5993 		/* No specific object, just general system-wide information. */
5994 		return avc_has_perm(&selinux_state,
5995 				    current_sid(), SECINITSID_KERNEL,
5996 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
5997 	case IPC_STAT:
5998 	case SHM_STAT:
5999 	case SHM_STAT_ANY:
6000 		perms = SHM__GETATTR | SHM__ASSOCIATE;
6001 		break;
6002 	case IPC_SET:
6003 		perms = SHM__SETATTR;
6004 		break;
6005 	case SHM_LOCK:
6006 	case SHM_UNLOCK:
6007 		perms = SHM__LOCK;
6008 		break;
6009 	case IPC_RMID:
6010 		perms = SHM__DESTROY;
6011 		break;
6012 	default:
6013 		return 0;
6014 	}
6015 
6016 	err = ipc_has_perm(shp, perms);
6017 	return err;
6018 }
6019 
6020 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6021 			     char __user *shmaddr, int shmflg)
6022 {
6023 	u32 perms;
6024 
6025 	if (shmflg & SHM_RDONLY)
6026 		perms = SHM__READ;
6027 	else
6028 		perms = SHM__READ | SHM__WRITE;
6029 
6030 	return ipc_has_perm(shp, perms);
6031 }
6032 
6033 /* Semaphore security operations */
6034 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6035 {
6036 	struct ipc_security_struct *isec;
6037 	struct common_audit_data ad;
6038 	u32 sid = current_sid();
6039 	int rc;
6040 
6041 	rc = ipc_alloc_security(sma, SECCLASS_SEM);
6042 	if (rc)
6043 		return rc;
6044 
6045 	isec = sma->security;
6046 
6047 	ad.type = LSM_AUDIT_DATA_IPC;
6048 	ad.u.ipc_id = sma->key;
6049 
6050 	rc = avc_has_perm(&selinux_state,
6051 			  sid, isec->sid, SECCLASS_SEM,
6052 			  SEM__CREATE, &ad);
6053 	if (rc) {
6054 		ipc_free_security(sma);
6055 		return rc;
6056 	}
6057 	return 0;
6058 }
6059 
6060 static void selinux_sem_free_security(struct kern_ipc_perm *sma)
6061 {
6062 	ipc_free_security(sma);
6063 }
6064 
6065 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6066 {
6067 	struct ipc_security_struct *isec;
6068 	struct common_audit_data ad;
6069 	u32 sid = current_sid();
6070 
6071 	isec = sma->security;
6072 
6073 	ad.type = LSM_AUDIT_DATA_IPC;
6074 	ad.u.ipc_id = sma->key;
6075 
6076 	return avc_has_perm(&selinux_state,
6077 			    sid, isec->sid, SECCLASS_SEM,
6078 			    SEM__ASSOCIATE, &ad);
6079 }
6080 
6081 /* Note, at this point, sma is locked down */
6082 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6083 {
6084 	int err;
6085 	u32 perms;
6086 
6087 	switch (cmd) {
6088 	case IPC_INFO:
6089 	case SEM_INFO:
6090 		/* No specific object, just general system-wide information. */
6091 		return avc_has_perm(&selinux_state,
6092 				    current_sid(), SECINITSID_KERNEL,
6093 				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6094 	case GETPID:
6095 	case GETNCNT:
6096 	case GETZCNT:
6097 		perms = SEM__GETATTR;
6098 		break;
6099 	case GETVAL:
6100 	case GETALL:
6101 		perms = SEM__READ;
6102 		break;
6103 	case SETVAL:
6104 	case SETALL:
6105 		perms = SEM__WRITE;
6106 		break;
6107 	case IPC_RMID:
6108 		perms = SEM__DESTROY;
6109 		break;
6110 	case IPC_SET:
6111 		perms = SEM__SETATTR;
6112 		break;
6113 	case IPC_STAT:
6114 	case SEM_STAT:
6115 	case SEM_STAT_ANY:
6116 		perms = SEM__GETATTR | SEM__ASSOCIATE;
6117 		break;
6118 	default:
6119 		return 0;
6120 	}
6121 
6122 	err = ipc_has_perm(sma, perms);
6123 	return err;
6124 }
6125 
6126 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6127 			     struct sembuf *sops, unsigned nsops, int alter)
6128 {
6129 	u32 perms;
6130 
6131 	if (alter)
6132 		perms = SEM__READ | SEM__WRITE;
6133 	else
6134 		perms = SEM__READ;
6135 
6136 	return ipc_has_perm(sma, perms);
6137 }
6138 
6139 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6140 {
6141 	u32 av = 0;
6142 
6143 	av = 0;
6144 	if (flag & S_IRUGO)
6145 		av |= IPC__UNIX_READ;
6146 	if (flag & S_IWUGO)
6147 		av |= IPC__UNIX_WRITE;
6148 
6149 	if (av == 0)
6150 		return 0;
6151 
6152 	return ipc_has_perm(ipcp, av);
6153 }
6154 
6155 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6156 {
6157 	struct ipc_security_struct *isec = ipcp->security;
6158 	*secid = isec->sid;
6159 }
6160 
6161 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6162 {
6163 	if (inode)
6164 		inode_doinit_with_dentry(inode, dentry);
6165 }
6166 
6167 static int selinux_getprocattr(struct task_struct *p,
6168 			       char *name, char **value)
6169 {
6170 	const struct task_security_struct *__tsec;
6171 	u32 sid;
6172 	int error;
6173 	unsigned len;
6174 
6175 	rcu_read_lock();
6176 	__tsec = __task_cred(p)->security;
6177 
6178 	if (current != p) {
6179 		error = avc_has_perm(&selinux_state,
6180 				     current_sid(), __tsec->sid,
6181 				     SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6182 		if (error)
6183 			goto bad;
6184 	}
6185 
6186 	if (!strcmp(name, "current"))
6187 		sid = __tsec->sid;
6188 	else if (!strcmp(name, "prev"))
6189 		sid = __tsec->osid;
6190 	else if (!strcmp(name, "exec"))
6191 		sid = __tsec->exec_sid;
6192 	else if (!strcmp(name, "fscreate"))
6193 		sid = __tsec->create_sid;
6194 	else if (!strcmp(name, "keycreate"))
6195 		sid = __tsec->keycreate_sid;
6196 	else if (!strcmp(name, "sockcreate"))
6197 		sid = __tsec->sockcreate_sid;
6198 	else {
6199 		error = -EINVAL;
6200 		goto bad;
6201 	}
6202 	rcu_read_unlock();
6203 
6204 	if (!sid)
6205 		return 0;
6206 
6207 	error = security_sid_to_context(&selinux_state, sid, value, &len);
6208 	if (error)
6209 		return error;
6210 	return len;
6211 
6212 bad:
6213 	rcu_read_unlock();
6214 	return error;
6215 }
6216 
6217 static int selinux_setprocattr(const char *name, void *value, size_t size)
6218 {
6219 	struct task_security_struct *tsec;
6220 	struct cred *new;
6221 	u32 mysid = current_sid(), sid = 0, ptsid;
6222 	int error;
6223 	char *str = value;
6224 
6225 	/*
6226 	 * Basic control over ability to set these attributes at all.
6227 	 */
6228 	if (!strcmp(name, "exec"))
6229 		error = avc_has_perm(&selinux_state,
6230 				     mysid, mysid, SECCLASS_PROCESS,
6231 				     PROCESS__SETEXEC, NULL);
6232 	else if (!strcmp(name, "fscreate"))
6233 		error = avc_has_perm(&selinux_state,
6234 				     mysid, mysid, SECCLASS_PROCESS,
6235 				     PROCESS__SETFSCREATE, NULL);
6236 	else if (!strcmp(name, "keycreate"))
6237 		error = avc_has_perm(&selinux_state,
6238 				     mysid, mysid, SECCLASS_PROCESS,
6239 				     PROCESS__SETKEYCREATE, NULL);
6240 	else if (!strcmp(name, "sockcreate"))
6241 		error = avc_has_perm(&selinux_state,
6242 				     mysid, mysid, SECCLASS_PROCESS,
6243 				     PROCESS__SETSOCKCREATE, NULL);
6244 	else if (!strcmp(name, "current"))
6245 		error = avc_has_perm(&selinux_state,
6246 				     mysid, mysid, SECCLASS_PROCESS,
6247 				     PROCESS__SETCURRENT, NULL);
6248 	else
6249 		error = -EINVAL;
6250 	if (error)
6251 		return error;
6252 
6253 	/* Obtain a SID for the context, if one was specified. */
6254 	if (size && str[0] && str[0] != '\n') {
6255 		if (str[size-1] == '\n') {
6256 			str[size-1] = 0;
6257 			size--;
6258 		}
6259 		error = security_context_to_sid(&selinux_state, value, size,
6260 						&sid, GFP_KERNEL);
6261 		if (error == -EINVAL && !strcmp(name, "fscreate")) {
6262 			if (!has_cap_mac_admin(true)) {
6263 				struct audit_buffer *ab;
6264 				size_t audit_size;
6265 
6266 				/* We strip a nul only if it is at the end, otherwise the
6267 				 * context contains a nul and we should audit that */
6268 				if (str[size - 1] == '\0')
6269 					audit_size = size - 1;
6270 				else
6271 					audit_size = size;
6272 				ab = audit_log_start(audit_context(),
6273 						     GFP_ATOMIC,
6274 						     AUDIT_SELINUX_ERR);
6275 				audit_log_format(ab, "op=fscreate invalid_context=");
6276 				audit_log_n_untrustedstring(ab, value, audit_size);
6277 				audit_log_end(ab);
6278 
6279 				return error;
6280 			}
6281 			error = security_context_to_sid_force(
6282 						      &selinux_state,
6283 						      value, size, &sid);
6284 		}
6285 		if (error)
6286 			return error;
6287 	}
6288 
6289 	new = prepare_creds();
6290 	if (!new)
6291 		return -ENOMEM;
6292 
6293 	/* Permission checking based on the specified context is
6294 	   performed during the actual operation (execve,
6295 	   open/mkdir/...), when we know the full context of the
6296 	   operation.  See selinux_bprm_set_creds for the execve
6297 	   checks and may_create for the file creation checks. The
6298 	   operation will then fail if the context is not permitted. */
6299 	tsec = new->security;
6300 	if (!strcmp(name, "exec")) {
6301 		tsec->exec_sid = sid;
6302 	} else if (!strcmp(name, "fscreate")) {
6303 		tsec->create_sid = sid;
6304 	} else if (!strcmp(name, "keycreate")) {
6305 		error = avc_has_perm(&selinux_state,
6306 				     mysid, sid, SECCLASS_KEY, KEY__CREATE,
6307 				     NULL);
6308 		if (error)
6309 			goto abort_change;
6310 		tsec->keycreate_sid = sid;
6311 	} else if (!strcmp(name, "sockcreate")) {
6312 		tsec->sockcreate_sid = sid;
6313 	} else if (!strcmp(name, "current")) {
6314 		error = -EINVAL;
6315 		if (sid == 0)
6316 			goto abort_change;
6317 
6318 		/* Only allow single threaded processes to change context */
6319 		error = -EPERM;
6320 		if (!current_is_single_threaded()) {
6321 			error = security_bounded_transition(&selinux_state,
6322 							    tsec->sid, sid);
6323 			if (error)
6324 				goto abort_change;
6325 		}
6326 
6327 		/* Check permissions for the transition. */
6328 		error = avc_has_perm(&selinux_state,
6329 				     tsec->sid, sid, SECCLASS_PROCESS,
6330 				     PROCESS__DYNTRANSITION, NULL);
6331 		if (error)
6332 			goto abort_change;
6333 
6334 		/* Check for ptracing, and update the task SID if ok.
6335 		   Otherwise, leave SID unchanged and fail. */
6336 		ptsid = ptrace_parent_sid();
6337 		if (ptsid != 0) {
6338 			error = avc_has_perm(&selinux_state,
6339 					     ptsid, sid, SECCLASS_PROCESS,
6340 					     PROCESS__PTRACE, NULL);
6341 			if (error)
6342 				goto abort_change;
6343 		}
6344 
6345 		tsec->sid = sid;
6346 	} else {
6347 		error = -EINVAL;
6348 		goto abort_change;
6349 	}
6350 
6351 	commit_creds(new);
6352 	return size;
6353 
6354 abort_change:
6355 	abort_creds(new);
6356 	return error;
6357 }
6358 
6359 static int selinux_ismaclabel(const char *name)
6360 {
6361 	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6362 }
6363 
6364 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6365 {
6366 	return security_sid_to_context(&selinux_state, secid,
6367 				       secdata, seclen);
6368 }
6369 
6370 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6371 {
6372 	return security_context_to_sid(&selinux_state, secdata, seclen,
6373 				       secid, GFP_KERNEL);
6374 }
6375 
6376 static void selinux_release_secctx(char *secdata, u32 seclen)
6377 {
6378 	kfree(secdata);
6379 }
6380 
6381 static void selinux_inode_invalidate_secctx(struct inode *inode)
6382 {
6383 	struct inode_security_struct *isec = inode->i_security;
6384 
6385 	spin_lock(&isec->lock);
6386 	isec->initialized = LABEL_INVALID;
6387 	spin_unlock(&isec->lock);
6388 }
6389 
6390 /*
6391  *	called with inode->i_mutex locked
6392  */
6393 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6394 {
6395 	return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
6396 }
6397 
6398 /*
6399  *	called with inode->i_mutex locked
6400  */
6401 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6402 {
6403 	return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6404 }
6405 
6406 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6407 {
6408 	int len = 0;
6409 	len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6410 						ctx, true);
6411 	if (len < 0)
6412 		return len;
6413 	*ctxlen = len;
6414 	return 0;
6415 }
6416 #ifdef CONFIG_KEYS
6417 
6418 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6419 			     unsigned long flags)
6420 {
6421 	const struct task_security_struct *tsec;
6422 	struct key_security_struct *ksec;
6423 
6424 	ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6425 	if (!ksec)
6426 		return -ENOMEM;
6427 
6428 	tsec = cred->security;
6429 	if (tsec->keycreate_sid)
6430 		ksec->sid = tsec->keycreate_sid;
6431 	else
6432 		ksec->sid = tsec->sid;
6433 
6434 	k->security = ksec;
6435 	return 0;
6436 }
6437 
6438 static void selinux_key_free(struct key *k)
6439 {
6440 	struct key_security_struct *ksec = k->security;
6441 
6442 	k->security = NULL;
6443 	kfree(ksec);
6444 }
6445 
6446 static int selinux_key_permission(key_ref_t key_ref,
6447 				  const struct cred *cred,
6448 				  unsigned perm)
6449 {
6450 	struct key *key;
6451 	struct key_security_struct *ksec;
6452 	u32 sid;
6453 
6454 	/* if no specific permissions are requested, we skip the
6455 	   permission check. No serious, additional covert channels
6456 	   appear to be created. */
6457 	if (perm == 0)
6458 		return 0;
6459 
6460 	sid = cred_sid(cred);
6461 
6462 	key = key_ref_to_ptr(key_ref);
6463 	ksec = key->security;
6464 
6465 	return avc_has_perm(&selinux_state,
6466 			    sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6467 }
6468 
6469 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6470 {
6471 	struct key_security_struct *ksec = key->security;
6472 	char *context = NULL;
6473 	unsigned len;
6474 	int rc;
6475 
6476 	rc = security_sid_to_context(&selinux_state, ksec->sid,
6477 				     &context, &len);
6478 	if (!rc)
6479 		rc = len;
6480 	*_buffer = context;
6481 	return rc;
6482 }
6483 #endif
6484 
6485 #ifdef CONFIG_SECURITY_INFINIBAND
6486 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6487 {
6488 	struct common_audit_data ad;
6489 	int err;
6490 	u32 sid = 0;
6491 	struct ib_security_struct *sec = ib_sec;
6492 	struct lsm_ibpkey_audit ibpkey;
6493 
6494 	err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6495 	if (err)
6496 		return err;
6497 
6498 	ad.type = LSM_AUDIT_DATA_IBPKEY;
6499 	ibpkey.subnet_prefix = subnet_prefix;
6500 	ibpkey.pkey = pkey_val;
6501 	ad.u.ibpkey = &ibpkey;
6502 	return avc_has_perm(&selinux_state,
6503 			    sec->sid, sid,
6504 			    SECCLASS_INFINIBAND_PKEY,
6505 			    INFINIBAND_PKEY__ACCESS, &ad);
6506 }
6507 
6508 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6509 					    u8 port_num)
6510 {
6511 	struct common_audit_data ad;
6512 	int err;
6513 	u32 sid = 0;
6514 	struct ib_security_struct *sec = ib_sec;
6515 	struct lsm_ibendport_audit ibendport;
6516 
6517 	err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6518 				      &sid);
6519 
6520 	if (err)
6521 		return err;
6522 
6523 	ad.type = LSM_AUDIT_DATA_IBENDPORT;
6524 	strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
6525 	ibendport.port = port_num;
6526 	ad.u.ibendport = &ibendport;
6527 	return avc_has_perm(&selinux_state,
6528 			    sec->sid, sid,
6529 			    SECCLASS_INFINIBAND_ENDPORT,
6530 			    INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6531 }
6532 
6533 static int selinux_ib_alloc_security(void **ib_sec)
6534 {
6535 	struct ib_security_struct *sec;
6536 
6537 	sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6538 	if (!sec)
6539 		return -ENOMEM;
6540 	sec->sid = current_sid();
6541 
6542 	*ib_sec = sec;
6543 	return 0;
6544 }
6545 
6546 static void selinux_ib_free_security(void *ib_sec)
6547 {
6548 	kfree(ib_sec);
6549 }
6550 #endif
6551 
6552 #ifdef CONFIG_BPF_SYSCALL
6553 static int selinux_bpf(int cmd, union bpf_attr *attr,
6554 				     unsigned int size)
6555 {
6556 	u32 sid = current_sid();
6557 	int ret;
6558 
6559 	switch (cmd) {
6560 	case BPF_MAP_CREATE:
6561 		ret = avc_has_perm(&selinux_state,
6562 				   sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6563 				   NULL);
6564 		break;
6565 	case BPF_PROG_LOAD:
6566 		ret = avc_has_perm(&selinux_state,
6567 				   sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6568 				   NULL);
6569 		break;
6570 	default:
6571 		ret = 0;
6572 		break;
6573 	}
6574 
6575 	return ret;
6576 }
6577 
6578 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6579 {
6580 	u32 av = 0;
6581 
6582 	if (fmode & FMODE_READ)
6583 		av |= BPF__MAP_READ;
6584 	if (fmode & FMODE_WRITE)
6585 		av |= BPF__MAP_WRITE;
6586 	return av;
6587 }
6588 
6589 /* This function will check the file pass through unix socket or binder to see
6590  * if it is a bpf related object. And apply correspinding checks on the bpf
6591  * object based on the type. The bpf maps and programs, not like other files and
6592  * socket, are using a shared anonymous inode inside the kernel as their inode.
6593  * So checking that inode cannot identify if the process have privilege to
6594  * access the bpf object and that's why we have to add this additional check in
6595  * selinux_file_receive and selinux_binder_transfer_files.
6596  */
6597 static int bpf_fd_pass(struct file *file, u32 sid)
6598 {
6599 	struct bpf_security_struct *bpfsec;
6600 	struct bpf_prog *prog;
6601 	struct bpf_map *map;
6602 	int ret;
6603 
6604 	if (file->f_op == &bpf_map_fops) {
6605 		map = file->private_data;
6606 		bpfsec = map->security;
6607 		ret = avc_has_perm(&selinux_state,
6608 				   sid, bpfsec->sid, SECCLASS_BPF,
6609 				   bpf_map_fmode_to_av(file->f_mode), NULL);
6610 		if (ret)
6611 			return ret;
6612 	} else if (file->f_op == &bpf_prog_fops) {
6613 		prog = file->private_data;
6614 		bpfsec = prog->aux->security;
6615 		ret = avc_has_perm(&selinux_state,
6616 				   sid, bpfsec->sid, SECCLASS_BPF,
6617 				   BPF__PROG_RUN, NULL);
6618 		if (ret)
6619 			return ret;
6620 	}
6621 	return 0;
6622 }
6623 
6624 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6625 {
6626 	u32 sid = current_sid();
6627 	struct bpf_security_struct *bpfsec;
6628 
6629 	bpfsec = map->security;
6630 	return avc_has_perm(&selinux_state,
6631 			    sid, bpfsec->sid, SECCLASS_BPF,
6632 			    bpf_map_fmode_to_av(fmode), NULL);
6633 }
6634 
6635 static int selinux_bpf_prog(struct bpf_prog *prog)
6636 {
6637 	u32 sid = current_sid();
6638 	struct bpf_security_struct *bpfsec;
6639 
6640 	bpfsec = prog->aux->security;
6641 	return avc_has_perm(&selinux_state,
6642 			    sid, bpfsec->sid, SECCLASS_BPF,
6643 			    BPF__PROG_RUN, NULL);
6644 }
6645 
6646 static int selinux_bpf_map_alloc(struct bpf_map *map)
6647 {
6648 	struct bpf_security_struct *bpfsec;
6649 
6650 	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6651 	if (!bpfsec)
6652 		return -ENOMEM;
6653 
6654 	bpfsec->sid = current_sid();
6655 	map->security = bpfsec;
6656 
6657 	return 0;
6658 }
6659 
6660 static void selinux_bpf_map_free(struct bpf_map *map)
6661 {
6662 	struct bpf_security_struct *bpfsec = map->security;
6663 
6664 	map->security = NULL;
6665 	kfree(bpfsec);
6666 }
6667 
6668 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6669 {
6670 	struct bpf_security_struct *bpfsec;
6671 
6672 	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6673 	if (!bpfsec)
6674 		return -ENOMEM;
6675 
6676 	bpfsec->sid = current_sid();
6677 	aux->security = bpfsec;
6678 
6679 	return 0;
6680 }
6681 
6682 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6683 {
6684 	struct bpf_security_struct *bpfsec = aux->security;
6685 
6686 	aux->security = NULL;
6687 	kfree(bpfsec);
6688 }
6689 #endif
6690 
6691 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6692 	LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6693 	LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6694 	LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6695 	LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6696 
6697 	LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6698 	LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6699 	LSM_HOOK_INIT(capget, selinux_capget),
6700 	LSM_HOOK_INIT(capset, selinux_capset),
6701 	LSM_HOOK_INIT(capable, selinux_capable),
6702 	LSM_HOOK_INIT(quotactl, selinux_quotactl),
6703 	LSM_HOOK_INIT(quota_on, selinux_quota_on),
6704 	LSM_HOOK_INIT(syslog, selinux_syslog),
6705 	LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6706 
6707 	LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6708 
6709 	LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
6710 	LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6711 	LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6712 
6713 	LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
6714 	LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6715 	LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
6716 	LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
6717 	LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6718 	LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6719 	LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6720 	LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6721 	LSM_HOOK_INIT(sb_mount, selinux_mount),
6722 	LSM_HOOK_INIT(sb_umount, selinux_umount),
6723 	LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6724 	LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6725 	LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt),
6726 
6727 	LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6728 	LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6729 
6730 	LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
6731 	LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6732 	LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6733 	LSM_HOOK_INIT(inode_create, selinux_inode_create),
6734 	LSM_HOOK_INIT(inode_link, selinux_inode_link),
6735 	LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6736 	LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6737 	LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6738 	LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6739 	LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6740 	LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6741 	LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
6742 	LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
6743 	LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
6744 	LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
6745 	LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
6746 	LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
6747 	LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
6748 	LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
6749 	LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
6750 	LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
6751 	LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
6752 	LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
6753 	LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
6754 	LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
6755 	LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6756 	LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6757 
6758 	LSM_HOOK_INIT(file_permission, selinux_file_permission),
6759 	LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
6760 	LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
6761 	LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
6762 	LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
6763 	LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
6764 	LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
6765 	LSM_HOOK_INIT(file_lock, selinux_file_lock),
6766 	LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
6767 	LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
6768 	LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
6769 	LSM_HOOK_INIT(file_receive, selinux_file_receive),
6770 
6771 	LSM_HOOK_INIT(file_open, selinux_file_open),
6772 
6773 	LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
6774 	LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
6775 	LSM_HOOK_INIT(cred_free, selinux_cred_free),
6776 	LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
6777 	LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
6778 	LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
6779 	LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
6780 	LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
6781 	LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6782 	LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
6783 	LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6784 	LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
6785 	LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
6786 	LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
6787 	LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
6788 	LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
6789 	LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
6790 	LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6791 	LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
6792 	LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
6793 	LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
6794 	LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
6795 	LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
6796 	LSM_HOOK_INIT(task_kill, selinux_task_kill),
6797 	LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
6798 
6799 	LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
6800 	LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
6801 
6802 	LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
6803 	LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),
6804 
6805 	LSM_HOOK_INIT(msg_queue_alloc_security,
6806 			selinux_msg_queue_alloc_security),
6807 	LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
6808 	LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
6809 	LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
6810 	LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
6811 	LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
6812 
6813 	LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
6814 	LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
6815 	LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
6816 	LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
6817 	LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
6818 
6819 	LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
6820 	LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
6821 	LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
6822 	LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
6823 	LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
6824 
6825 	LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
6826 
6827 	LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
6828 	LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
6829 
6830 	LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
6831 	LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
6832 	LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
6833 	LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
6834 	LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6835 	LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
6836 	LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
6837 	LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
6838 
6839 	LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
6840 	LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
6841 
6842 	LSM_HOOK_INIT(socket_create, selinux_socket_create),
6843 	LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
6844 	LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
6845 	LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
6846 	LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
6847 	LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
6848 	LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
6849 	LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
6850 	LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
6851 	LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
6852 	LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
6853 	LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
6854 	LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
6855 	LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
6856 	LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
6857 	LSM_HOOK_INIT(socket_getpeersec_stream,
6858 			selinux_socket_getpeersec_stream),
6859 	LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
6860 	LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
6861 	LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
6862 	LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
6863 	LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
6864 	LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
6865 	LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
6866 	LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
6867 	LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
6868 	LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
6869 	LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
6870 	LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
6871 	LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
6872 	LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
6873 	LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
6874 	LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
6875 	LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
6876 	LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
6877 	LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
6878 	LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
6879 	LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
6880 	LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
6881 #ifdef CONFIG_SECURITY_INFINIBAND
6882 	LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
6883 	LSM_HOOK_INIT(ib_endport_manage_subnet,
6884 		      selinux_ib_endport_manage_subnet),
6885 	LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
6886 	LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
6887 #endif
6888 #ifdef CONFIG_SECURITY_NETWORK_XFRM
6889 	LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
6890 	LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
6891 	LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
6892 	LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
6893 	LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
6894 	LSM_HOOK_INIT(xfrm_state_alloc_acquire,
6895 			selinux_xfrm_state_alloc_acquire),
6896 	LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
6897 	LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
6898 	LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
6899 	LSM_HOOK_INIT(xfrm_state_pol_flow_match,
6900 			selinux_xfrm_state_pol_flow_match),
6901 	LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
6902 #endif
6903 
6904 #ifdef CONFIG_KEYS
6905 	LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
6906 	LSM_HOOK_INIT(key_free, selinux_key_free),
6907 	LSM_HOOK_INIT(key_permission, selinux_key_permission),
6908 	LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
6909 #endif
6910 
6911 #ifdef CONFIG_AUDIT
6912 	LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
6913 	LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
6914 	LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
6915 	LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
6916 #endif
6917 
6918 #ifdef CONFIG_BPF_SYSCALL
6919 	LSM_HOOK_INIT(bpf, selinux_bpf),
6920 	LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
6921 	LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
6922 	LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
6923 	LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
6924 	LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
6925 	LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
6926 #endif
6927 };
6928 
6929 static __init int selinux_init(void)
6930 {
6931 	if (!security_module_enable("selinux")) {
6932 		selinux_enabled = 0;
6933 		return 0;
6934 	}
6935 
6936 	if (!selinux_enabled) {
6937 		pr_info("SELinux:  Disabled at boot.\n");
6938 		return 0;
6939 	}
6940 
6941 	pr_info("SELinux:  Initializing.\n");
6942 
6943 	memset(&selinux_state, 0, sizeof(selinux_state));
6944 	enforcing_set(&selinux_state, selinux_enforcing_boot);
6945 	selinux_state.checkreqprot = selinux_checkreqprot_boot;
6946 	selinux_ss_init(&selinux_state.ss);
6947 	selinux_avc_init(&selinux_state.avc);
6948 
6949 	/* Set the security state for the initial task. */
6950 	cred_init_security();
6951 
6952 	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
6953 
6954 	sel_inode_cache = kmem_cache_create("selinux_inode_security",
6955 					    sizeof(struct inode_security_struct),
6956 					    0, SLAB_PANIC, NULL);
6957 	file_security_cache = kmem_cache_create("selinux_file_security",
6958 					    sizeof(struct file_security_struct),
6959 					    0, SLAB_PANIC, NULL);
6960 	avc_init();
6961 
6962 	avtab_cache_init();
6963 
6964 	ebitmap_cache_init();
6965 
6966 	hashtab_cache_init();
6967 
6968 	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
6969 
6970 	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
6971 		panic("SELinux: Unable to register AVC netcache callback\n");
6972 
6973 	if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
6974 		panic("SELinux: Unable to register AVC LSM notifier callback\n");
6975 
6976 	if (selinux_enforcing_boot)
6977 		pr_debug("SELinux:  Starting in enforcing mode\n");
6978 	else
6979 		pr_debug("SELinux:  Starting in permissive mode\n");
6980 
6981 	return 0;
6982 }
6983 
6984 static void delayed_superblock_init(struct super_block *sb, void *unused)
6985 {
6986 	selinux_set_mnt_opts(sb, NULL, 0, NULL);
6987 }
6988 
6989 void selinux_complete_init(void)
6990 {
6991 	pr_debug("SELinux:  Completing initialization.\n");
6992 
6993 	/* Set up any superblocks initialized prior to the policy load. */
6994 	pr_debug("SELinux:  Setting up existing superblocks.\n");
6995 	iterate_supers(delayed_superblock_init, NULL);
6996 }
6997 
6998 /* SELinux requires early initialization in order to label
6999    all processes and objects when they are created. */
7000 DEFINE_LSM(selinux) = {
7001 	.name = "selinux",
7002 	.init = selinux_init,
7003 };
7004 
7005 #if defined(CONFIG_NETFILTER)
7006 
7007 static const struct nf_hook_ops selinux_nf_ops[] = {
7008 	{
7009 		.hook =		selinux_ipv4_postroute,
7010 		.pf =		NFPROTO_IPV4,
7011 		.hooknum =	NF_INET_POST_ROUTING,
7012 		.priority =	NF_IP_PRI_SELINUX_LAST,
7013 	},
7014 	{
7015 		.hook =		selinux_ipv4_forward,
7016 		.pf =		NFPROTO_IPV4,
7017 		.hooknum =	NF_INET_FORWARD,
7018 		.priority =	NF_IP_PRI_SELINUX_FIRST,
7019 	},
7020 	{
7021 		.hook =		selinux_ipv4_output,
7022 		.pf =		NFPROTO_IPV4,
7023 		.hooknum =	NF_INET_LOCAL_OUT,
7024 		.priority =	NF_IP_PRI_SELINUX_FIRST,
7025 	},
7026 #if IS_ENABLED(CONFIG_IPV6)
7027 	{
7028 		.hook =		selinux_ipv6_postroute,
7029 		.pf =		NFPROTO_IPV6,
7030 		.hooknum =	NF_INET_POST_ROUTING,
7031 		.priority =	NF_IP6_PRI_SELINUX_LAST,
7032 	},
7033 	{
7034 		.hook =		selinux_ipv6_forward,
7035 		.pf =		NFPROTO_IPV6,
7036 		.hooknum =	NF_INET_FORWARD,
7037 		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7038 	},
7039 	{
7040 		.hook =		selinux_ipv6_output,
7041 		.pf =		NFPROTO_IPV6,
7042 		.hooknum =	NF_INET_LOCAL_OUT,
7043 		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7044 	},
7045 #endif	/* IPV6 */
7046 };
7047 
7048 static int __net_init selinux_nf_register(struct net *net)
7049 {
7050 	return nf_register_net_hooks(net, selinux_nf_ops,
7051 				     ARRAY_SIZE(selinux_nf_ops));
7052 }
7053 
7054 static void __net_exit selinux_nf_unregister(struct net *net)
7055 {
7056 	nf_unregister_net_hooks(net, selinux_nf_ops,
7057 				ARRAY_SIZE(selinux_nf_ops));
7058 }
7059 
7060 static struct pernet_operations selinux_net_ops = {
7061 	.init = selinux_nf_register,
7062 	.exit = selinux_nf_unregister,
7063 };
7064 
7065 static int __init selinux_nf_ip_init(void)
7066 {
7067 	int err;
7068 
7069 	if (!selinux_enabled)
7070 		return 0;
7071 
7072 	pr_debug("SELinux:  Registering netfilter hooks\n");
7073 
7074 	err = register_pernet_subsys(&selinux_net_ops);
7075 	if (err)
7076 		panic("SELinux: register_pernet_subsys: error %d\n", err);
7077 
7078 	return 0;
7079 }
7080 __initcall(selinux_nf_ip_init);
7081 
7082 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7083 static void selinux_nf_ip_exit(void)
7084 {
7085 	pr_debug("SELinux:  Unregistering netfilter hooks\n");
7086 
7087 	unregister_pernet_subsys(&selinux_net_ops);
7088 }
7089 #endif
7090 
7091 #else /* CONFIG_NETFILTER */
7092 
7093 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7094 #define selinux_nf_ip_exit()
7095 #endif
7096 
7097 #endif /* CONFIG_NETFILTER */
7098 
7099 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7100 int selinux_disable(struct selinux_state *state)
7101 {
7102 	if (state->initialized) {
7103 		/* Not permitted after initial policy load. */
7104 		return -EINVAL;
7105 	}
7106 
7107 	if (state->disabled) {
7108 		/* Only do this once. */
7109 		return -EINVAL;
7110 	}
7111 
7112 	state->disabled = 1;
7113 
7114 	pr_info("SELinux:  Disabled at runtime.\n");
7115 
7116 	selinux_enabled = 0;
7117 
7118 	security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7119 
7120 	/* Try to destroy the avc node cache */
7121 	avc_disable();
7122 
7123 	/* Unregister netfilter hooks. */
7124 	selinux_nf_ip_exit();
7125 
7126 	/* Unregister selinuxfs. */
7127 	exit_sel_fs();
7128 
7129 	return 0;
7130 }
7131 #endif
7132