xref: /openbmc/linux/security/selinux/hooks.c (revision 259e5e6c75a910f3b5e656151dc602f53f9d7548)
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@epoch.ncsc.mil>
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  *
21  *	This program is free software; you can redistribute it and/or modify
22  *	it under the terms of the GNU General Public License version 2,
23  *	as published by the Free Software Foundation.
24  */
25 
26 #include <linux/init.h>
27 #include <linux/kd.h>
28 #include <linux/kernel.h>
29 #include <linux/tracehook.h>
30 #include <linux/errno.h>
31 #include <linux/sched.h>
32 #include <linux/security.h>
33 #include <linux/xattr.h>
34 #include <linux/capability.h>
35 #include <linux/unistd.h>
36 #include <linux/mm.h>
37 #include <linux/mman.h>
38 #include <linux/slab.h>
39 #include <linux/pagemap.h>
40 #include <linux/proc_fs.h>
41 #include <linux/swap.h>
42 #include <linux/spinlock.h>
43 #include <linux/syscalls.h>
44 #include <linux/dcache.h>
45 #include <linux/file.h>
46 #include <linux/fdtable.h>
47 #include <linux/namei.h>
48 #include <linux/mount.h>
49 #include <linux/netfilter_ipv4.h>
50 #include <linux/netfilter_ipv6.h>
51 #include <linux/tty.h>
52 #include <net/icmp.h>
53 #include <net/ip.h>		/* for local_port_range[] */
54 #include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
55 #include <net/net_namespace.h>
56 #include <net/netlabel.h>
57 #include <linux/uaccess.h>
58 #include <asm/ioctls.h>
59 #include <linux/atomic.h>
60 #include <linux/bitops.h>
61 #include <linux/interrupt.h>
62 #include <linux/netdevice.h>	/* for network interface checks */
63 #include <linux/netlink.h>
64 #include <linux/tcp.h>
65 #include <linux/udp.h>
66 #include <linux/dccp.h>
67 #include <linux/quota.h>
68 #include <linux/un.h>		/* for Unix socket types */
69 #include <net/af_unix.h>	/* for Unix socket types */
70 #include <linux/parser.h>
71 #include <linux/nfs_mount.h>
72 #include <net/ipv6.h>
73 #include <linux/hugetlb.h>
74 #include <linux/personality.h>
75 #include <linux/audit.h>
76 #include <linux/string.h>
77 #include <linux/selinux.h>
78 #include <linux/mutex.h>
79 #include <linux/posix-timers.h>
80 #include <linux/syslog.h>
81 #include <linux/user_namespace.h>
82 #include <linux/export.h>
83 #include <linux/msg.h>
84 #include <linux/shm.h>
85 
86 #include "avc.h"
87 #include "objsec.h"
88 #include "netif.h"
89 #include "netnode.h"
90 #include "netport.h"
91 #include "xfrm.h"
92 #include "netlabel.h"
93 #include "audit.h"
94 #include "avc_ss.h"
95 
96 #define NUM_SEL_MNT_OPTS 5
97 
98 extern struct security_operations *security_ops;
99 
100 /* SECMARK reference count */
101 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
102 
103 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
104 int selinux_enforcing;
105 
106 static int __init enforcing_setup(char *str)
107 {
108 	unsigned long enforcing;
109 	if (!strict_strtoul(str, 0, &enforcing))
110 		selinux_enforcing = enforcing ? 1 : 0;
111 	return 1;
112 }
113 __setup("enforcing=", enforcing_setup);
114 #endif
115 
116 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
117 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
118 
119 static int __init selinux_enabled_setup(char *str)
120 {
121 	unsigned long enabled;
122 	if (!strict_strtoul(str, 0, &enabled))
123 		selinux_enabled = enabled ? 1 : 0;
124 	return 1;
125 }
126 __setup("selinux=", selinux_enabled_setup);
127 #else
128 int selinux_enabled = 1;
129 #endif
130 
131 static struct kmem_cache *sel_inode_cache;
132 
133 /**
134  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
135  *
136  * Description:
137  * This function checks the SECMARK reference counter to see if any SECMARK
138  * targets are currently configured, if the reference counter is greater than
139  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
140  * enabled, false (0) if SECMARK is disabled.
141  *
142  */
143 static int selinux_secmark_enabled(void)
144 {
145 	return (atomic_read(&selinux_secmark_refcount) > 0);
146 }
147 
148 /*
149  * initialise the security for the init task
150  */
151 static void cred_init_security(void)
152 {
153 	struct cred *cred = (struct cred *) current->real_cred;
154 	struct task_security_struct *tsec;
155 
156 	tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
157 	if (!tsec)
158 		panic("SELinux:  Failed to initialize initial task.\n");
159 
160 	tsec->osid = tsec->sid = SECINITSID_KERNEL;
161 	cred->security = tsec;
162 }
163 
164 /*
165  * get the security ID of a set of credentials
166  */
167 static inline u32 cred_sid(const struct cred *cred)
168 {
169 	const struct task_security_struct *tsec;
170 
171 	tsec = cred->security;
172 	return tsec->sid;
173 }
174 
175 /*
176  * get the objective security ID of a task
177  */
178 static inline u32 task_sid(const struct task_struct *task)
179 {
180 	u32 sid;
181 
182 	rcu_read_lock();
183 	sid = cred_sid(__task_cred(task));
184 	rcu_read_unlock();
185 	return sid;
186 }
187 
188 /*
189  * get the subjective security ID of the current task
190  */
191 static inline u32 current_sid(void)
192 {
193 	const struct task_security_struct *tsec = current_security();
194 
195 	return tsec->sid;
196 }
197 
198 /* Allocate and free functions for each kind of security blob. */
199 
200 static int inode_alloc_security(struct inode *inode)
201 {
202 	struct inode_security_struct *isec;
203 	u32 sid = current_sid();
204 
205 	isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
206 	if (!isec)
207 		return -ENOMEM;
208 
209 	mutex_init(&isec->lock);
210 	INIT_LIST_HEAD(&isec->list);
211 	isec->inode = inode;
212 	isec->sid = SECINITSID_UNLABELED;
213 	isec->sclass = SECCLASS_FILE;
214 	isec->task_sid = sid;
215 	inode->i_security = isec;
216 
217 	return 0;
218 }
219 
220 static void inode_free_security(struct inode *inode)
221 {
222 	struct inode_security_struct *isec = inode->i_security;
223 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
224 
225 	spin_lock(&sbsec->isec_lock);
226 	if (!list_empty(&isec->list))
227 		list_del_init(&isec->list);
228 	spin_unlock(&sbsec->isec_lock);
229 
230 	inode->i_security = NULL;
231 	kmem_cache_free(sel_inode_cache, isec);
232 }
233 
234 static int file_alloc_security(struct file *file)
235 {
236 	struct file_security_struct *fsec;
237 	u32 sid = current_sid();
238 
239 	fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
240 	if (!fsec)
241 		return -ENOMEM;
242 
243 	fsec->sid = sid;
244 	fsec->fown_sid = sid;
245 	file->f_security = fsec;
246 
247 	return 0;
248 }
249 
250 static void file_free_security(struct file *file)
251 {
252 	struct file_security_struct *fsec = file->f_security;
253 	file->f_security = NULL;
254 	kfree(fsec);
255 }
256 
257 static int superblock_alloc_security(struct super_block *sb)
258 {
259 	struct superblock_security_struct *sbsec;
260 
261 	sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
262 	if (!sbsec)
263 		return -ENOMEM;
264 
265 	mutex_init(&sbsec->lock);
266 	INIT_LIST_HEAD(&sbsec->isec_head);
267 	spin_lock_init(&sbsec->isec_lock);
268 	sbsec->sb = sb;
269 	sbsec->sid = SECINITSID_UNLABELED;
270 	sbsec->def_sid = SECINITSID_FILE;
271 	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
272 	sb->s_security = sbsec;
273 
274 	return 0;
275 }
276 
277 static void superblock_free_security(struct super_block *sb)
278 {
279 	struct superblock_security_struct *sbsec = sb->s_security;
280 	sb->s_security = NULL;
281 	kfree(sbsec);
282 }
283 
284 /* The file system's label must be initialized prior to use. */
285 
286 static const char *labeling_behaviors[6] = {
287 	"uses xattr",
288 	"uses transition SIDs",
289 	"uses task SIDs",
290 	"uses genfs_contexts",
291 	"not configured for labeling",
292 	"uses mountpoint labeling",
293 };
294 
295 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
296 
297 static inline int inode_doinit(struct inode *inode)
298 {
299 	return inode_doinit_with_dentry(inode, NULL);
300 }
301 
302 enum {
303 	Opt_error = -1,
304 	Opt_context = 1,
305 	Opt_fscontext = 2,
306 	Opt_defcontext = 3,
307 	Opt_rootcontext = 4,
308 	Opt_labelsupport = 5,
309 };
310 
311 static const match_table_t tokens = {
312 	{Opt_context, CONTEXT_STR "%s"},
313 	{Opt_fscontext, FSCONTEXT_STR "%s"},
314 	{Opt_defcontext, DEFCONTEXT_STR "%s"},
315 	{Opt_rootcontext, ROOTCONTEXT_STR "%s"},
316 	{Opt_labelsupport, LABELSUPP_STR},
317 	{Opt_error, NULL},
318 };
319 
320 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
321 
322 static int may_context_mount_sb_relabel(u32 sid,
323 			struct superblock_security_struct *sbsec,
324 			const struct cred *cred)
325 {
326 	const struct task_security_struct *tsec = cred->security;
327 	int rc;
328 
329 	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
330 			  FILESYSTEM__RELABELFROM, NULL);
331 	if (rc)
332 		return rc;
333 
334 	rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
335 			  FILESYSTEM__RELABELTO, NULL);
336 	return rc;
337 }
338 
339 static int may_context_mount_inode_relabel(u32 sid,
340 			struct superblock_security_struct *sbsec,
341 			const struct cred *cred)
342 {
343 	const struct task_security_struct *tsec = cred->security;
344 	int rc;
345 	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
346 			  FILESYSTEM__RELABELFROM, NULL);
347 	if (rc)
348 		return rc;
349 
350 	rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
351 			  FILESYSTEM__ASSOCIATE, NULL);
352 	return rc;
353 }
354 
355 static int sb_finish_set_opts(struct super_block *sb)
356 {
357 	struct superblock_security_struct *sbsec = sb->s_security;
358 	struct dentry *root = sb->s_root;
359 	struct inode *root_inode = root->d_inode;
360 	int rc = 0;
361 
362 	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
363 		/* Make sure that the xattr handler exists and that no
364 		   error other than -ENODATA is returned by getxattr on
365 		   the root directory.  -ENODATA is ok, as this may be
366 		   the first boot of the SELinux kernel before we have
367 		   assigned xattr values to the filesystem. */
368 		if (!root_inode->i_op->getxattr) {
369 			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
370 			       "xattr support\n", sb->s_id, sb->s_type->name);
371 			rc = -EOPNOTSUPP;
372 			goto out;
373 		}
374 		rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
375 		if (rc < 0 && rc != -ENODATA) {
376 			if (rc == -EOPNOTSUPP)
377 				printk(KERN_WARNING "SELinux: (dev %s, type "
378 				       "%s) has no security xattr handler\n",
379 				       sb->s_id, sb->s_type->name);
380 			else
381 				printk(KERN_WARNING "SELinux: (dev %s, type "
382 				       "%s) getxattr errno %d\n", sb->s_id,
383 				       sb->s_type->name, -rc);
384 			goto out;
385 		}
386 	}
387 
388 	sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
389 
390 	if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
391 		printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
392 		       sb->s_id, sb->s_type->name);
393 	else
394 		printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
395 		       sb->s_id, sb->s_type->name,
396 		       labeling_behaviors[sbsec->behavior-1]);
397 
398 	if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
399 	    sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
400 	    sbsec->behavior == SECURITY_FS_USE_NONE ||
401 	    sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
402 		sbsec->flags &= ~SE_SBLABELSUPP;
403 
404 	/* Special handling for sysfs. Is genfs but also has setxattr handler*/
405 	if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
406 		sbsec->flags |= SE_SBLABELSUPP;
407 
408 	/* Initialize the root inode. */
409 	rc = inode_doinit_with_dentry(root_inode, root);
410 
411 	/* Initialize any other inodes associated with the superblock, e.g.
412 	   inodes created prior to initial policy load or inodes created
413 	   during get_sb by a pseudo filesystem that directly
414 	   populates itself. */
415 	spin_lock(&sbsec->isec_lock);
416 next_inode:
417 	if (!list_empty(&sbsec->isec_head)) {
418 		struct inode_security_struct *isec =
419 				list_entry(sbsec->isec_head.next,
420 					   struct inode_security_struct, list);
421 		struct inode *inode = isec->inode;
422 		spin_unlock(&sbsec->isec_lock);
423 		inode = igrab(inode);
424 		if (inode) {
425 			if (!IS_PRIVATE(inode))
426 				inode_doinit(inode);
427 			iput(inode);
428 		}
429 		spin_lock(&sbsec->isec_lock);
430 		list_del_init(&isec->list);
431 		goto next_inode;
432 	}
433 	spin_unlock(&sbsec->isec_lock);
434 out:
435 	return rc;
436 }
437 
438 /*
439  * This function should allow an FS to ask what it's mount security
440  * options were so it can use those later for submounts, displaying
441  * mount options, or whatever.
442  */
443 static int selinux_get_mnt_opts(const struct super_block *sb,
444 				struct security_mnt_opts *opts)
445 {
446 	int rc = 0, i;
447 	struct superblock_security_struct *sbsec = sb->s_security;
448 	char *context = NULL;
449 	u32 len;
450 	char tmp;
451 
452 	security_init_mnt_opts(opts);
453 
454 	if (!(sbsec->flags & SE_SBINITIALIZED))
455 		return -EINVAL;
456 
457 	if (!ss_initialized)
458 		return -EINVAL;
459 
460 	tmp = sbsec->flags & SE_MNTMASK;
461 	/* count the number of mount options for this sb */
462 	for (i = 0; i < 8; i++) {
463 		if (tmp & 0x01)
464 			opts->num_mnt_opts++;
465 		tmp >>= 1;
466 	}
467 	/* Check if the Label support flag is set */
468 	if (sbsec->flags & SE_SBLABELSUPP)
469 		opts->num_mnt_opts++;
470 
471 	opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
472 	if (!opts->mnt_opts) {
473 		rc = -ENOMEM;
474 		goto out_free;
475 	}
476 
477 	opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
478 	if (!opts->mnt_opts_flags) {
479 		rc = -ENOMEM;
480 		goto out_free;
481 	}
482 
483 	i = 0;
484 	if (sbsec->flags & FSCONTEXT_MNT) {
485 		rc = security_sid_to_context(sbsec->sid, &context, &len);
486 		if (rc)
487 			goto out_free;
488 		opts->mnt_opts[i] = context;
489 		opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
490 	}
491 	if (sbsec->flags & CONTEXT_MNT) {
492 		rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
493 		if (rc)
494 			goto out_free;
495 		opts->mnt_opts[i] = context;
496 		opts->mnt_opts_flags[i++] = CONTEXT_MNT;
497 	}
498 	if (sbsec->flags & DEFCONTEXT_MNT) {
499 		rc = security_sid_to_context(sbsec->def_sid, &context, &len);
500 		if (rc)
501 			goto out_free;
502 		opts->mnt_opts[i] = context;
503 		opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
504 	}
505 	if (sbsec->flags & ROOTCONTEXT_MNT) {
506 		struct inode *root = sbsec->sb->s_root->d_inode;
507 		struct inode_security_struct *isec = root->i_security;
508 
509 		rc = security_sid_to_context(isec->sid, &context, &len);
510 		if (rc)
511 			goto out_free;
512 		opts->mnt_opts[i] = context;
513 		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
514 	}
515 	if (sbsec->flags & SE_SBLABELSUPP) {
516 		opts->mnt_opts[i] = NULL;
517 		opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
518 	}
519 
520 	BUG_ON(i != opts->num_mnt_opts);
521 
522 	return 0;
523 
524 out_free:
525 	security_free_mnt_opts(opts);
526 	return rc;
527 }
528 
529 static int bad_option(struct superblock_security_struct *sbsec, char flag,
530 		      u32 old_sid, u32 new_sid)
531 {
532 	char mnt_flags = sbsec->flags & SE_MNTMASK;
533 
534 	/* check if the old mount command had the same options */
535 	if (sbsec->flags & SE_SBINITIALIZED)
536 		if (!(sbsec->flags & flag) ||
537 		    (old_sid != new_sid))
538 			return 1;
539 
540 	/* check if we were passed the same options twice,
541 	 * aka someone passed context=a,context=b
542 	 */
543 	if (!(sbsec->flags & SE_SBINITIALIZED))
544 		if (mnt_flags & flag)
545 			return 1;
546 	return 0;
547 }
548 
549 /*
550  * Allow filesystems with binary mount data to explicitly set mount point
551  * labeling information.
552  */
553 static int selinux_set_mnt_opts(struct super_block *sb,
554 				struct security_mnt_opts *opts)
555 {
556 	const struct cred *cred = current_cred();
557 	int rc = 0, i;
558 	struct superblock_security_struct *sbsec = sb->s_security;
559 	const char *name = sb->s_type->name;
560 	struct inode *inode = sbsec->sb->s_root->d_inode;
561 	struct inode_security_struct *root_isec = inode->i_security;
562 	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
563 	u32 defcontext_sid = 0;
564 	char **mount_options = opts->mnt_opts;
565 	int *flags = opts->mnt_opts_flags;
566 	int num_opts = opts->num_mnt_opts;
567 
568 	mutex_lock(&sbsec->lock);
569 
570 	if (!ss_initialized) {
571 		if (!num_opts) {
572 			/* Defer initialization until selinux_complete_init,
573 			   after the initial policy is loaded and the security
574 			   server is ready to handle calls. */
575 			goto out;
576 		}
577 		rc = -EINVAL;
578 		printk(KERN_WARNING "SELinux: Unable to set superblock options "
579 			"before the security server is initialized\n");
580 		goto out;
581 	}
582 
583 	/*
584 	 * Binary mount data FS will come through this function twice.  Once
585 	 * from an explicit call and once from the generic calls from the vfs.
586 	 * Since the generic VFS calls will not contain any security mount data
587 	 * we need to skip the double mount verification.
588 	 *
589 	 * This does open a hole in which we will not notice if the first
590 	 * mount using this sb set explict options and a second mount using
591 	 * this sb does not set any security options.  (The first options
592 	 * will be used for both mounts)
593 	 */
594 	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
595 	    && (num_opts == 0))
596 		goto out;
597 
598 	/*
599 	 * parse the mount options, check if they are valid sids.
600 	 * also check if someone is trying to mount the same sb more
601 	 * than once with different security options.
602 	 */
603 	for (i = 0; i < num_opts; i++) {
604 		u32 sid;
605 
606 		if (flags[i] == SE_SBLABELSUPP)
607 			continue;
608 		rc = security_context_to_sid(mount_options[i],
609 					     strlen(mount_options[i]), &sid);
610 		if (rc) {
611 			printk(KERN_WARNING "SELinux: security_context_to_sid"
612 			       "(%s) failed for (dev %s, type %s) errno=%d\n",
613 			       mount_options[i], sb->s_id, name, rc);
614 			goto out;
615 		}
616 		switch (flags[i]) {
617 		case FSCONTEXT_MNT:
618 			fscontext_sid = sid;
619 
620 			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
621 					fscontext_sid))
622 				goto out_double_mount;
623 
624 			sbsec->flags |= FSCONTEXT_MNT;
625 			break;
626 		case CONTEXT_MNT:
627 			context_sid = sid;
628 
629 			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
630 					context_sid))
631 				goto out_double_mount;
632 
633 			sbsec->flags |= CONTEXT_MNT;
634 			break;
635 		case ROOTCONTEXT_MNT:
636 			rootcontext_sid = sid;
637 
638 			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
639 					rootcontext_sid))
640 				goto out_double_mount;
641 
642 			sbsec->flags |= ROOTCONTEXT_MNT;
643 
644 			break;
645 		case DEFCONTEXT_MNT:
646 			defcontext_sid = sid;
647 
648 			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
649 					defcontext_sid))
650 				goto out_double_mount;
651 
652 			sbsec->flags |= DEFCONTEXT_MNT;
653 
654 			break;
655 		default:
656 			rc = -EINVAL;
657 			goto out;
658 		}
659 	}
660 
661 	if (sbsec->flags & SE_SBINITIALIZED) {
662 		/* previously mounted with options, but not on this attempt? */
663 		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
664 			goto out_double_mount;
665 		rc = 0;
666 		goto out;
667 	}
668 
669 	if (strcmp(sb->s_type->name, "proc") == 0)
670 		sbsec->flags |= SE_SBPROC;
671 
672 	/* Determine the labeling behavior to use for this filesystem type. */
673 	rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
674 	if (rc) {
675 		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
676 		       __func__, sb->s_type->name, rc);
677 		goto out;
678 	}
679 
680 	/* sets the context of the superblock for the fs being mounted. */
681 	if (fscontext_sid) {
682 		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
683 		if (rc)
684 			goto out;
685 
686 		sbsec->sid = fscontext_sid;
687 	}
688 
689 	/*
690 	 * Switch to using mount point labeling behavior.
691 	 * sets the label used on all file below the mountpoint, and will set
692 	 * the superblock context if not already set.
693 	 */
694 	if (context_sid) {
695 		if (!fscontext_sid) {
696 			rc = may_context_mount_sb_relabel(context_sid, sbsec,
697 							  cred);
698 			if (rc)
699 				goto out;
700 			sbsec->sid = context_sid;
701 		} else {
702 			rc = may_context_mount_inode_relabel(context_sid, sbsec,
703 							     cred);
704 			if (rc)
705 				goto out;
706 		}
707 		if (!rootcontext_sid)
708 			rootcontext_sid = context_sid;
709 
710 		sbsec->mntpoint_sid = context_sid;
711 		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
712 	}
713 
714 	if (rootcontext_sid) {
715 		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
716 						     cred);
717 		if (rc)
718 			goto out;
719 
720 		root_isec->sid = rootcontext_sid;
721 		root_isec->initialized = 1;
722 	}
723 
724 	if (defcontext_sid) {
725 		if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
726 			rc = -EINVAL;
727 			printk(KERN_WARNING "SELinux: defcontext option is "
728 			       "invalid for this filesystem type\n");
729 			goto out;
730 		}
731 
732 		if (defcontext_sid != sbsec->def_sid) {
733 			rc = may_context_mount_inode_relabel(defcontext_sid,
734 							     sbsec, cred);
735 			if (rc)
736 				goto out;
737 		}
738 
739 		sbsec->def_sid = defcontext_sid;
740 	}
741 
742 	rc = sb_finish_set_opts(sb);
743 out:
744 	mutex_unlock(&sbsec->lock);
745 	return rc;
746 out_double_mount:
747 	rc = -EINVAL;
748 	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
749 	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
750 	goto out;
751 }
752 
753 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
754 					struct super_block *newsb)
755 {
756 	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
757 	struct superblock_security_struct *newsbsec = newsb->s_security;
758 
759 	int set_fscontext =	(oldsbsec->flags & FSCONTEXT_MNT);
760 	int set_context =	(oldsbsec->flags & CONTEXT_MNT);
761 	int set_rootcontext =	(oldsbsec->flags & ROOTCONTEXT_MNT);
762 
763 	/*
764 	 * if the parent was able to be mounted it clearly had no special lsm
765 	 * mount options.  thus we can safely deal with this superblock later
766 	 */
767 	if (!ss_initialized)
768 		return;
769 
770 	/* how can we clone if the old one wasn't set up?? */
771 	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
772 
773 	/* if fs is reusing a sb, just let its options stand... */
774 	if (newsbsec->flags & SE_SBINITIALIZED)
775 		return;
776 
777 	mutex_lock(&newsbsec->lock);
778 
779 	newsbsec->flags = oldsbsec->flags;
780 
781 	newsbsec->sid = oldsbsec->sid;
782 	newsbsec->def_sid = oldsbsec->def_sid;
783 	newsbsec->behavior = oldsbsec->behavior;
784 
785 	if (set_context) {
786 		u32 sid = oldsbsec->mntpoint_sid;
787 
788 		if (!set_fscontext)
789 			newsbsec->sid = sid;
790 		if (!set_rootcontext) {
791 			struct inode *newinode = newsb->s_root->d_inode;
792 			struct inode_security_struct *newisec = newinode->i_security;
793 			newisec->sid = sid;
794 		}
795 		newsbsec->mntpoint_sid = sid;
796 	}
797 	if (set_rootcontext) {
798 		const struct inode *oldinode = oldsb->s_root->d_inode;
799 		const struct inode_security_struct *oldisec = oldinode->i_security;
800 		struct inode *newinode = newsb->s_root->d_inode;
801 		struct inode_security_struct *newisec = newinode->i_security;
802 
803 		newisec->sid = oldisec->sid;
804 	}
805 
806 	sb_finish_set_opts(newsb);
807 	mutex_unlock(&newsbsec->lock);
808 }
809 
810 static int selinux_parse_opts_str(char *options,
811 				  struct security_mnt_opts *opts)
812 {
813 	char *p;
814 	char *context = NULL, *defcontext = NULL;
815 	char *fscontext = NULL, *rootcontext = NULL;
816 	int rc, num_mnt_opts = 0;
817 
818 	opts->num_mnt_opts = 0;
819 
820 	/* Standard string-based options. */
821 	while ((p = strsep(&options, "|")) != NULL) {
822 		int token;
823 		substring_t args[MAX_OPT_ARGS];
824 
825 		if (!*p)
826 			continue;
827 
828 		token = match_token(p, tokens, args);
829 
830 		switch (token) {
831 		case Opt_context:
832 			if (context || defcontext) {
833 				rc = -EINVAL;
834 				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
835 				goto out_err;
836 			}
837 			context = match_strdup(&args[0]);
838 			if (!context) {
839 				rc = -ENOMEM;
840 				goto out_err;
841 			}
842 			break;
843 
844 		case Opt_fscontext:
845 			if (fscontext) {
846 				rc = -EINVAL;
847 				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
848 				goto out_err;
849 			}
850 			fscontext = match_strdup(&args[0]);
851 			if (!fscontext) {
852 				rc = -ENOMEM;
853 				goto out_err;
854 			}
855 			break;
856 
857 		case Opt_rootcontext:
858 			if (rootcontext) {
859 				rc = -EINVAL;
860 				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
861 				goto out_err;
862 			}
863 			rootcontext = match_strdup(&args[0]);
864 			if (!rootcontext) {
865 				rc = -ENOMEM;
866 				goto out_err;
867 			}
868 			break;
869 
870 		case Opt_defcontext:
871 			if (context || defcontext) {
872 				rc = -EINVAL;
873 				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
874 				goto out_err;
875 			}
876 			defcontext = match_strdup(&args[0]);
877 			if (!defcontext) {
878 				rc = -ENOMEM;
879 				goto out_err;
880 			}
881 			break;
882 		case Opt_labelsupport:
883 			break;
884 		default:
885 			rc = -EINVAL;
886 			printk(KERN_WARNING "SELinux:  unknown mount option\n");
887 			goto out_err;
888 
889 		}
890 	}
891 
892 	rc = -ENOMEM;
893 	opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
894 	if (!opts->mnt_opts)
895 		goto out_err;
896 
897 	opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
898 	if (!opts->mnt_opts_flags) {
899 		kfree(opts->mnt_opts);
900 		goto out_err;
901 	}
902 
903 	if (fscontext) {
904 		opts->mnt_opts[num_mnt_opts] = fscontext;
905 		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
906 	}
907 	if (context) {
908 		opts->mnt_opts[num_mnt_opts] = context;
909 		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
910 	}
911 	if (rootcontext) {
912 		opts->mnt_opts[num_mnt_opts] = rootcontext;
913 		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
914 	}
915 	if (defcontext) {
916 		opts->mnt_opts[num_mnt_opts] = defcontext;
917 		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
918 	}
919 
920 	opts->num_mnt_opts = num_mnt_opts;
921 	return 0;
922 
923 out_err:
924 	kfree(context);
925 	kfree(defcontext);
926 	kfree(fscontext);
927 	kfree(rootcontext);
928 	return rc;
929 }
930 /*
931  * string mount options parsing and call set the sbsec
932  */
933 static int superblock_doinit(struct super_block *sb, void *data)
934 {
935 	int rc = 0;
936 	char *options = data;
937 	struct security_mnt_opts opts;
938 
939 	security_init_mnt_opts(&opts);
940 
941 	if (!data)
942 		goto out;
943 
944 	BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
945 
946 	rc = selinux_parse_opts_str(options, &opts);
947 	if (rc)
948 		goto out_err;
949 
950 out:
951 	rc = selinux_set_mnt_opts(sb, &opts);
952 
953 out_err:
954 	security_free_mnt_opts(&opts);
955 	return rc;
956 }
957 
958 static void selinux_write_opts(struct seq_file *m,
959 			       struct security_mnt_opts *opts)
960 {
961 	int i;
962 	char *prefix;
963 
964 	for (i = 0; i < opts->num_mnt_opts; i++) {
965 		char *has_comma;
966 
967 		if (opts->mnt_opts[i])
968 			has_comma = strchr(opts->mnt_opts[i], ',');
969 		else
970 			has_comma = NULL;
971 
972 		switch (opts->mnt_opts_flags[i]) {
973 		case CONTEXT_MNT:
974 			prefix = CONTEXT_STR;
975 			break;
976 		case FSCONTEXT_MNT:
977 			prefix = FSCONTEXT_STR;
978 			break;
979 		case ROOTCONTEXT_MNT:
980 			prefix = ROOTCONTEXT_STR;
981 			break;
982 		case DEFCONTEXT_MNT:
983 			prefix = DEFCONTEXT_STR;
984 			break;
985 		case SE_SBLABELSUPP:
986 			seq_putc(m, ',');
987 			seq_puts(m, LABELSUPP_STR);
988 			continue;
989 		default:
990 			BUG();
991 			return;
992 		};
993 		/* we need a comma before each option */
994 		seq_putc(m, ',');
995 		seq_puts(m, prefix);
996 		if (has_comma)
997 			seq_putc(m, '\"');
998 		seq_puts(m, opts->mnt_opts[i]);
999 		if (has_comma)
1000 			seq_putc(m, '\"');
1001 	}
1002 }
1003 
1004 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1005 {
1006 	struct security_mnt_opts opts;
1007 	int rc;
1008 
1009 	rc = selinux_get_mnt_opts(sb, &opts);
1010 	if (rc) {
1011 		/* before policy load we may get EINVAL, don't show anything */
1012 		if (rc == -EINVAL)
1013 			rc = 0;
1014 		return rc;
1015 	}
1016 
1017 	selinux_write_opts(m, &opts);
1018 
1019 	security_free_mnt_opts(&opts);
1020 
1021 	return rc;
1022 }
1023 
1024 static inline u16 inode_mode_to_security_class(umode_t mode)
1025 {
1026 	switch (mode & S_IFMT) {
1027 	case S_IFSOCK:
1028 		return SECCLASS_SOCK_FILE;
1029 	case S_IFLNK:
1030 		return SECCLASS_LNK_FILE;
1031 	case S_IFREG:
1032 		return SECCLASS_FILE;
1033 	case S_IFBLK:
1034 		return SECCLASS_BLK_FILE;
1035 	case S_IFDIR:
1036 		return SECCLASS_DIR;
1037 	case S_IFCHR:
1038 		return SECCLASS_CHR_FILE;
1039 	case S_IFIFO:
1040 		return SECCLASS_FIFO_FILE;
1041 
1042 	}
1043 
1044 	return SECCLASS_FILE;
1045 }
1046 
1047 static inline int default_protocol_stream(int protocol)
1048 {
1049 	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1050 }
1051 
1052 static inline int default_protocol_dgram(int protocol)
1053 {
1054 	return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1055 }
1056 
1057 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1058 {
1059 	switch (family) {
1060 	case PF_UNIX:
1061 		switch (type) {
1062 		case SOCK_STREAM:
1063 		case SOCK_SEQPACKET:
1064 			return SECCLASS_UNIX_STREAM_SOCKET;
1065 		case SOCK_DGRAM:
1066 			return SECCLASS_UNIX_DGRAM_SOCKET;
1067 		}
1068 		break;
1069 	case PF_INET:
1070 	case PF_INET6:
1071 		switch (type) {
1072 		case SOCK_STREAM:
1073 			if (default_protocol_stream(protocol))
1074 				return SECCLASS_TCP_SOCKET;
1075 			else
1076 				return SECCLASS_RAWIP_SOCKET;
1077 		case SOCK_DGRAM:
1078 			if (default_protocol_dgram(protocol))
1079 				return SECCLASS_UDP_SOCKET;
1080 			else
1081 				return SECCLASS_RAWIP_SOCKET;
1082 		case SOCK_DCCP:
1083 			return SECCLASS_DCCP_SOCKET;
1084 		default:
1085 			return SECCLASS_RAWIP_SOCKET;
1086 		}
1087 		break;
1088 	case PF_NETLINK:
1089 		switch (protocol) {
1090 		case NETLINK_ROUTE:
1091 			return SECCLASS_NETLINK_ROUTE_SOCKET;
1092 		case NETLINK_FIREWALL:
1093 			return SECCLASS_NETLINK_FIREWALL_SOCKET;
1094 		case NETLINK_SOCK_DIAG:
1095 			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1096 		case NETLINK_NFLOG:
1097 			return SECCLASS_NETLINK_NFLOG_SOCKET;
1098 		case NETLINK_XFRM:
1099 			return SECCLASS_NETLINK_XFRM_SOCKET;
1100 		case NETLINK_SELINUX:
1101 			return SECCLASS_NETLINK_SELINUX_SOCKET;
1102 		case NETLINK_AUDIT:
1103 			return SECCLASS_NETLINK_AUDIT_SOCKET;
1104 		case NETLINK_IP6_FW:
1105 			return SECCLASS_NETLINK_IP6FW_SOCKET;
1106 		case NETLINK_DNRTMSG:
1107 			return SECCLASS_NETLINK_DNRT_SOCKET;
1108 		case NETLINK_KOBJECT_UEVENT:
1109 			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1110 		default:
1111 			return SECCLASS_NETLINK_SOCKET;
1112 		}
1113 	case PF_PACKET:
1114 		return SECCLASS_PACKET_SOCKET;
1115 	case PF_KEY:
1116 		return SECCLASS_KEY_SOCKET;
1117 	case PF_APPLETALK:
1118 		return SECCLASS_APPLETALK_SOCKET;
1119 	}
1120 
1121 	return SECCLASS_SOCKET;
1122 }
1123 
1124 #ifdef CONFIG_PROC_FS
1125 static int selinux_proc_get_sid(struct dentry *dentry,
1126 				u16 tclass,
1127 				u32 *sid)
1128 {
1129 	int rc;
1130 	char *buffer, *path;
1131 
1132 	buffer = (char *)__get_free_page(GFP_KERNEL);
1133 	if (!buffer)
1134 		return -ENOMEM;
1135 
1136 	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1137 	if (IS_ERR(path))
1138 		rc = PTR_ERR(path);
1139 	else {
1140 		/* each process gets a /proc/PID/ entry. Strip off the
1141 		 * PID part to get a valid selinux labeling.
1142 		 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1143 		while (path[1] >= '0' && path[1] <= '9') {
1144 			path[1] = '/';
1145 			path++;
1146 		}
1147 		rc = security_genfs_sid("proc", path, tclass, sid);
1148 	}
1149 	free_page((unsigned long)buffer);
1150 	return rc;
1151 }
1152 #else
1153 static int selinux_proc_get_sid(struct dentry *dentry,
1154 				u16 tclass,
1155 				u32 *sid)
1156 {
1157 	return -EINVAL;
1158 }
1159 #endif
1160 
1161 /* The inode's security attributes must be initialized before first use. */
1162 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1163 {
1164 	struct superblock_security_struct *sbsec = NULL;
1165 	struct inode_security_struct *isec = inode->i_security;
1166 	u32 sid;
1167 	struct dentry *dentry;
1168 #define INITCONTEXTLEN 255
1169 	char *context = NULL;
1170 	unsigned len = 0;
1171 	int rc = 0;
1172 
1173 	if (isec->initialized)
1174 		goto out;
1175 
1176 	mutex_lock(&isec->lock);
1177 	if (isec->initialized)
1178 		goto out_unlock;
1179 
1180 	sbsec = inode->i_sb->s_security;
1181 	if (!(sbsec->flags & SE_SBINITIALIZED)) {
1182 		/* Defer initialization until selinux_complete_init,
1183 		   after the initial policy is loaded and the security
1184 		   server is ready to handle calls. */
1185 		spin_lock(&sbsec->isec_lock);
1186 		if (list_empty(&isec->list))
1187 			list_add(&isec->list, &sbsec->isec_head);
1188 		spin_unlock(&sbsec->isec_lock);
1189 		goto out_unlock;
1190 	}
1191 
1192 	switch (sbsec->behavior) {
1193 	case SECURITY_FS_USE_XATTR:
1194 		if (!inode->i_op->getxattr) {
1195 			isec->sid = sbsec->def_sid;
1196 			break;
1197 		}
1198 
1199 		/* Need a dentry, since the xattr API requires one.
1200 		   Life would be simpler if we could just pass the inode. */
1201 		if (opt_dentry) {
1202 			/* Called from d_instantiate or d_splice_alias. */
1203 			dentry = dget(opt_dentry);
1204 		} else {
1205 			/* Called from selinux_complete_init, try to find a dentry. */
1206 			dentry = d_find_alias(inode);
1207 		}
1208 		if (!dentry) {
1209 			/*
1210 			 * this is can be hit on boot when a file is accessed
1211 			 * before the policy is loaded.  When we load policy we
1212 			 * may find inodes that have no dentry on the
1213 			 * sbsec->isec_head list.  No reason to complain as these
1214 			 * will get fixed up the next time we go through
1215 			 * inode_doinit with a dentry, before these inodes could
1216 			 * be used again by userspace.
1217 			 */
1218 			goto out_unlock;
1219 		}
1220 
1221 		len = INITCONTEXTLEN;
1222 		context = kmalloc(len+1, GFP_NOFS);
1223 		if (!context) {
1224 			rc = -ENOMEM;
1225 			dput(dentry);
1226 			goto out_unlock;
1227 		}
1228 		context[len] = '\0';
1229 		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1230 					   context, len);
1231 		if (rc == -ERANGE) {
1232 			kfree(context);
1233 
1234 			/* Need a larger buffer.  Query for the right size. */
1235 			rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1236 						   NULL, 0);
1237 			if (rc < 0) {
1238 				dput(dentry);
1239 				goto out_unlock;
1240 			}
1241 			len = rc;
1242 			context = kmalloc(len+1, GFP_NOFS);
1243 			if (!context) {
1244 				rc = -ENOMEM;
1245 				dput(dentry);
1246 				goto out_unlock;
1247 			}
1248 			context[len] = '\0';
1249 			rc = inode->i_op->getxattr(dentry,
1250 						   XATTR_NAME_SELINUX,
1251 						   context, len);
1252 		}
1253 		dput(dentry);
1254 		if (rc < 0) {
1255 			if (rc != -ENODATA) {
1256 				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1257 				       "%d for dev=%s ino=%ld\n", __func__,
1258 				       -rc, inode->i_sb->s_id, inode->i_ino);
1259 				kfree(context);
1260 				goto out_unlock;
1261 			}
1262 			/* Map ENODATA to the default file SID */
1263 			sid = sbsec->def_sid;
1264 			rc = 0;
1265 		} else {
1266 			rc = security_context_to_sid_default(context, rc, &sid,
1267 							     sbsec->def_sid,
1268 							     GFP_NOFS);
1269 			if (rc) {
1270 				char *dev = inode->i_sb->s_id;
1271 				unsigned long ino = inode->i_ino;
1272 
1273 				if (rc == -EINVAL) {
1274 					if (printk_ratelimit())
1275 						printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1276 							"context=%s.  This indicates you may need to relabel the inode or the "
1277 							"filesystem in question.\n", ino, dev, context);
1278 				} else {
1279 					printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1280 					       "returned %d for dev=%s ino=%ld\n",
1281 					       __func__, context, -rc, dev, ino);
1282 				}
1283 				kfree(context);
1284 				/* Leave with the unlabeled SID */
1285 				rc = 0;
1286 				break;
1287 			}
1288 		}
1289 		kfree(context);
1290 		isec->sid = sid;
1291 		break;
1292 	case SECURITY_FS_USE_TASK:
1293 		isec->sid = isec->task_sid;
1294 		break;
1295 	case SECURITY_FS_USE_TRANS:
1296 		/* Default to the fs SID. */
1297 		isec->sid = sbsec->sid;
1298 
1299 		/* Try to obtain a transition SID. */
1300 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
1301 		rc = security_transition_sid(isec->task_sid, sbsec->sid,
1302 					     isec->sclass, NULL, &sid);
1303 		if (rc)
1304 			goto out_unlock;
1305 		isec->sid = sid;
1306 		break;
1307 	case SECURITY_FS_USE_MNTPOINT:
1308 		isec->sid = sbsec->mntpoint_sid;
1309 		break;
1310 	default:
1311 		/* Default to the fs superblock SID. */
1312 		isec->sid = sbsec->sid;
1313 
1314 		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1315 			if (opt_dentry) {
1316 				isec->sclass = inode_mode_to_security_class(inode->i_mode);
1317 				rc = selinux_proc_get_sid(opt_dentry,
1318 							  isec->sclass,
1319 							  &sid);
1320 				if (rc)
1321 					goto out_unlock;
1322 				isec->sid = sid;
1323 			}
1324 		}
1325 		break;
1326 	}
1327 
1328 	isec->initialized = 1;
1329 
1330 out_unlock:
1331 	mutex_unlock(&isec->lock);
1332 out:
1333 	if (isec->sclass == SECCLASS_FILE)
1334 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
1335 	return rc;
1336 }
1337 
1338 /* Convert a Linux signal to an access vector. */
1339 static inline u32 signal_to_av(int sig)
1340 {
1341 	u32 perm = 0;
1342 
1343 	switch (sig) {
1344 	case SIGCHLD:
1345 		/* Commonly granted from child to parent. */
1346 		perm = PROCESS__SIGCHLD;
1347 		break;
1348 	case SIGKILL:
1349 		/* Cannot be caught or ignored */
1350 		perm = PROCESS__SIGKILL;
1351 		break;
1352 	case SIGSTOP:
1353 		/* Cannot be caught or ignored */
1354 		perm = PROCESS__SIGSTOP;
1355 		break;
1356 	default:
1357 		/* All other signals. */
1358 		perm = PROCESS__SIGNAL;
1359 		break;
1360 	}
1361 
1362 	return perm;
1363 }
1364 
1365 /*
1366  * Check permission between a pair of credentials
1367  * fork check, ptrace check, etc.
1368  */
1369 static int cred_has_perm(const struct cred *actor,
1370 			 const struct cred *target,
1371 			 u32 perms)
1372 {
1373 	u32 asid = cred_sid(actor), tsid = cred_sid(target);
1374 
1375 	return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1376 }
1377 
1378 /*
1379  * Check permission between a pair of tasks, e.g. signal checks,
1380  * fork check, ptrace check, etc.
1381  * tsk1 is the actor and tsk2 is the target
1382  * - this uses the default subjective creds of tsk1
1383  */
1384 static int task_has_perm(const struct task_struct *tsk1,
1385 			 const struct task_struct *tsk2,
1386 			 u32 perms)
1387 {
1388 	const struct task_security_struct *__tsec1, *__tsec2;
1389 	u32 sid1, sid2;
1390 
1391 	rcu_read_lock();
1392 	__tsec1 = __task_cred(tsk1)->security;	sid1 = __tsec1->sid;
1393 	__tsec2 = __task_cred(tsk2)->security;	sid2 = __tsec2->sid;
1394 	rcu_read_unlock();
1395 	return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1396 }
1397 
1398 /*
1399  * Check permission between current and another task, e.g. signal checks,
1400  * fork check, ptrace check, etc.
1401  * current is the actor and tsk2 is the target
1402  * - this uses current's subjective creds
1403  */
1404 static int current_has_perm(const struct task_struct *tsk,
1405 			    u32 perms)
1406 {
1407 	u32 sid, tsid;
1408 
1409 	sid = current_sid();
1410 	tsid = task_sid(tsk);
1411 	return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1412 }
1413 
1414 #if CAP_LAST_CAP > 63
1415 #error Fix SELinux to handle capabilities > 63.
1416 #endif
1417 
1418 /* Check whether a task is allowed to use a capability. */
1419 static int cred_has_capability(const struct cred *cred,
1420 			       int cap, int audit)
1421 {
1422 	struct common_audit_data ad;
1423 	struct selinux_audit_data sad = {0,};
1424 	struct av_decision avd;
1425 	u16 sclass;
1426 	u32 sid = cred_sid(cred);
1427 	u32 av = CAP_TO_MASK(cap);
1428 	int rc;
1429 
1430 	COMMON_AUDIT_DATA_INIT(&ad, CAP);
1431 	ad.selinux_audit_data = &sad;
1432 	ad.tsk = current;
1433 	ad.u.cap = cap;
1434 
1435 	switch (CAP_TO_INDEX(cap)) {
1436 	case 0:
1437 		sclass = SECCLASS_CAPABILITY;
1438 		break;
1439 	case 1:
1440 		sclass = SECCLASS_CAPABILITY2;
1441 		break;
1442 	default:
1443 		printk(KERN_ERR
1444 		       "SELinux:  out of range capability %d\n", cap);
1445 		BUG();
1446 		return -EINVAL;
1447 	}
1448 
1449 	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1450 	if (audit == SECURITY_CAP_AUDIT) {
1451 		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1452 		if (rc2)
1453 			return rc2;
1454 	}
1455 	return rc;
1456 }
1457 
1458 /* Check whether a task is allowed to use a system operation. */
1459 static int task_has_system(struct task_struct *tsk,
1460 			   u32 perms)
1461 {
1462 	u32 sid = task_sid(tsk);
1463 
1464 	return avc_has_perm(sid, SECINITSID_KERNEL,
1465 			    SECCLASS_SYSTEM, perms, NULL);
1466 }
1467 
1468 /* Check whether a task has a particular permission to an inode.
1469    The 'adp' parameter is optional and allows other audit
1470    data to be passed (e.g. the dentry). */
1471 static int inode_has_perm(const struct cred *cred,
1472 			  struct inode *inode,
1473 			  u32 perms,
1474 			  struct common_audit_data *adp,
1475 			  unsigned flags)
1476 {
1477 	struct inode_security_struct *isec;
1478 	u32 sid;
1479 
1480 	validate_creds(cred);
1481 
1482 	if (unlikely(IS_PRIVATE(inode)))
1483 		return 0;
1484 
1485 	sid = cred_sid(cred);
1486 	isec = inode->i_security;
1487 
1488 	return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1489 }
1490 
1491 static int inode_has_perm_noadp(const struct cred *cred,
1492 				struct inode *inode,
1493 				u32 perms,
1494 				unsigned flags)
1495 {
1496 	struct common_audit_data ad;
1497 	struct selinux_audit_data sad = {0,};
1498 
1499 	COMMON_AUDIT_DATA_INIT(&ad, INODE);
1500 	ad.u.inode = inode;
1501 	ad.selinux_audit_data = &sad;
1502 	return inode_has_perm(cred, inode, perms, &ad, flags);
1503 }
1504 
1505 /* Same as inode_has_perm, but pass explicit audit data containing
1506    the dentry to help the auditing code to more easily generate the
1507    pathname if needed. */
1508 static inline int dentry_has_perm(const struct cred *cred,
1509 				  struct dentry *dentry,
1510 				  u32 av)
1511 {
1512 	struct inode *inode = dentry->d_inode;
1513 	struct common_audit_data ad;
1514 	struct selinux_audit_data sad = {0,};
1515 
1516 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1517 	ad.u.dentry = dentry;
1518 	ad.selinux_audit_data = &sad;
1519 	return inode_has_perm(cred, inode, av, &ad, 0);
1520 }
1521 
1522 /* Same as inode_has_perm, but pass explicit audit data containing
1523    the path to help the auditing code to more easily generate the
1524    pathname if needed. */
1525 static inline int path_has_perm(const struct cred *cred,
1526 				struct path *path,
1527 				u32 av)
1528 {
1529 	struct inode *inode = path->dentry->d_inode;
1530 	struct common_audit_data ad;
1531 	struct selinux_audit_data sad = {0,};
1532 
1533 	COMMON_AUDIT_DATA_INIT(&ad, PATH);
1534 	ad.u.path = *path;
1535 	ad.selinux_audit_data = &sad;
1536 	return inode_has_perm(cred, inode, av, &ad, 0);
1537 }
1538 
1539 /* Check whether a task can use an open file descriptor to
1540    access an inode in a given way.  Check access to the
1541    descriptor itself, and then use dentry_has_perm to
1542    check a particular permission to the file.
1543    Access to the descriptor is implicitly granted if it
1544    has the same SID as the process.  If av is zero, then
1545    access to the file is not checked, e.g. for cases
1546    where only the descriptor is affected like seek. */
1547 static int file_has_perm(const struct cred *cred,
1548 			 struct file *file,
1549 			 u32 av)
1550 {
1551 	struct file_security_struct *fsec = file->f_security;
1552 	struct inode *inode = file->f_path.dentry->d_inode;
1553 	struct common_audit_data ad;
1554 	struct selinux_audit_data sad = {0,};
1555 	u32 sid = cred_sid(cred);
1556 	int rc;
1557 
1558 	COMMON_AUDIT_DATA_INIT(&ad, PATH);
1559 	ad.u.path = file->f_path;
1560 	ad.selinux_audit_data = &sad;
1561 
1562 	if (sid != fsec->sid) {
1563 		rc = avc_has_perm(sid, fsec->sid,
1564 				  SECCLASS_FD,
1565 				  FD__USE,
1566 				  &ad);
1567 		if (rc)
1568 			goto out;
1569 	}
1570 
1571 	/* av is zero if only checking access to the descriptor. */
1572 	rc = 0;
1573 	if (av)
1574 		rc = inode_has_perm(cred, inode, av, &ad, 0);
1575 
1576 out:
1577 	return rc;
1578 }
1579 
1580 /* Check whether a task can create a file. */
1581 static int may_create(struct inode *dir,
1582 		      struct dentry *dentry,
1583 		      u16 tclass)
1584 {
1585 	const struct task_security_struct *tsec = current_security();
1586 	struct inode_security_struct *dsec;
1587 	struct superblock_security_struct *sbsec;
1588 	u32 sid, newsid;
1589 	struct common_audit_data ad;
1590 	struct selinux_audit_data sad = {0,};
1591 	int rc;
1592 
1593 	dsec = dir->i_security;
1594 	sbsec = dir->i_sb->s_security;
1595 
1596 	sid = tsec->sid;
1597 	newsid = tsec->create_sid;
1598 
1599 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1600 	ad.u.dentry = dentry;
1601 	ad.selinux_audit_data = &sad;
1602 
1603 	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1604 			  DIR__ADD_NAME | DIR__SEARCH,
1605 			  &ad);
1606 	if (rc)
1607 		return rc;
1608 
1609 	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1610 		rc = security_transition_sid(sid, dsec->sid, tclass,
1611 					     &dentry->d_name, &newsid);
1612 		if (rc)
1613 			return rc;
1614 	}
1615 
1616 	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1617 	if (rc)
1618 		return rc;
1619 
1620 	return avc_has_perm(newsid, sbsec->sid,
1621 			    SECCLASS_FILESYSTEM,
1622 			    FILESYSTEM__ASSOCIATE, &ad);
1623 }
1624 
1625 /* Check whether a task can create a key. */
1626 static int may_create_key(u32 ksid,
1627 			  struct task_struct *ctx)
1628 {
1629 	u32 sid = task_sid(ctx);
1630 
1631 	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1632 }
1633 
1634 #define MAY_LINK	0
1635 #define MAY_UNLINK	1
1636 #define MAY_RMDIR	2
1637 
1638 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1639 static int may_link(struct inode *dir,
1640 		    struct dentry *dentry,
1641 		    int kind)
1642 
1643 {
1644 	struct inode_security_struct *dsec, *isec;
1645 	struct common_audit_data ad;
1646 	struct selinux_audit_data sad = {0,};
1647 	u32 sid = current_sid();
1648 	u32 av;
1649 	int rc;
1650 
1651 	dsec = dir->i_security;
1652 	isec = dentry->d_inode->i_security;
1653 
1654 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1655 	ad.u.dentry = dentry;
1656 	ad.selinux_audit_data = &sad;
1657 
1658 	av = DIR__SEARCH;
1659 	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1660 	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1661 	if (rc)
1662 		return rc;
1663 
1664 	switch (kind) {
1665 	case MAY_LINK:
1666 		av = FILE__LINK;
1667 		break;
1668 	case MAY_UNLINK:
1669 		av = FILE__UNLINK;
1670 		break;
1671 	case MAY_RMDIR:
1672 		av = DIR__RMDIR;
1673 		break;
1674 	default:
1675 		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1676 			__func__, kind);
1677 		return 0;
1678 	}
1679 
1680 	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1681 	return rc;
1682 }
1683 
1684 static inline int may_rename(struct inode *old_dir,
1685 			     struct dentry *old_dentry,
1686 			     struct inode *new_dir,
1687 			     struct dentry *new_dentry)
1688 {
1689 	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1690 	struct common_audit_data ad;
1691 	struct selinux_audit_data sad = {0,};
1692 	u32 sid = current_sid();
1693 	u32 av;
1694 	int old_is_dir, new_is_dir;
1695 	int rc;
1696 
1697 	old_dsec = old_dir->i_security;
1698 	old_isec = old_dentry->d_inode->i_security;
1699 	old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1700 	new_dsec = new_dir->i_security;
1701 
1702 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1703 	ad.selinux_audit_data = &sad;
1704 
1705 	ad.u.dentry = old_dentry;
1706 	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1707 			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1708 	if (rc)
1709 		return rc;
1710 	rc = avc_has_perm(sid, old_isec->sid,
1711 			  old_isec->sclass, FILE__RENAME, &ad);
1712 	if (rc)
1713 		return rc;
1714 	if (old_is_dir && new_dir != old_dir) {
1715 		rc = avc_has_perm(sid, old_isec->sid,
1716 				  old_isec->sclass, DIR__REPARENT, &ad);
1717 		if (rc)
1718 			return rc;
1719 	}
1720 
1721 	ad.u.dentry = new_dentry;
1722 	av = DIR__ADD_NAME | DIR__SEARCH;
1723 	if (new_dentry->d_inode)
1724 		av |= DIR__REMOVE_NAME;
1725 	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1726 	if (rc)
1727 		return rc;
1728 	if (new_dentry->d_inode) {
1729 		new_isec = new_dentry->d_inode->i_security;
1730 		new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1731 		rc = avc_has_perm(sid, new_isec->sid,
1732 				  new_isec->sclass,
1733 				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1734 		if (rc)
1735 			return rc;
1736 	}
1737 
1738 	return 0;
1739 }
1740 
1741 /* Check whether a task can perform a filesystem operation. */
1742 static int superblock_has_perm(const struct cred *cred,
1743 			       struct super_block *sb,
1744 			       u32 perms,
1745 			       struct common_audit_data *ad)
1746 {
1747 	struct superblock_security_struct *sbsec;
1748 	u32 sid = cred_sid(cred);
1749 
1750 	sbsec = sb->s_security;
1751 	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1752 }
1753 
1754 /* Convert a Linux mode and permission mask to an access vector. */
1755 static inline u32 file_mask_to_av(int mode, int mask)
1756 {
1757 	u32 av = 0;
1758 
1759 	if (!S_ISDIR(mode)) {
1760 		if (mask & MAY_EXEC)
1761 			av |= FILE__EXECUTE;
1762 		if (mask & MAY_READ)
1763 			av |= FILE__READ;
1764 
1765 		if (mask & MAY_APPEND)
1766 			av |= FILE__APPEND;
1767 		else if (mask & MAY_WRITE)
1768 			av |= FILE__WRITE;
1769 
1770 	} else {
1771 		if (mask & MAY_EXEC)
1772 			av |= DIR__SEARCH;
1773 		if (mask & MAY_WRITE)
1774 			av |= DIR__WRITE;
1775 		if (mask & MAY_READ)
1776 			av |= DIR__READ;
1777 	}
1778 
1779 	return av;
1780 }
1781 
1782 /* Convert a Linux file to an access vector. */
1783 static inline u32 file_to_av(struct file *file)
1784 {
1785 	u32 av = 0;
1786 
1787 	if (file->f_mode & FMODE_READ)
1788 		av |= FILE__READ;
1789 	if (file->f_mode & FMODE_WRITE) {
1790 		if (file->f_flags & O_APPEND)
1791 			av |= FILE__APPEND;
1792 		else
1793 			av |= FILE__WRITE;
1794 	}
1795 	if (!av) {
1796 		/*
1797 		 * Special file opened with flags 3 for ioctl-only use.
1798 		 */
1799 		av = FILE__IOCTL;
1800 	}
1801 
1802 	return av;
1803 }
1804 
1805 /*
1806  * Convert a file to an access vector and include the correct open
1807  * open permission.
1808  */
1809 static inline u32 open_file_to_av(struct file *file)
1810 {
1811 	u32 av = file_to_av(file);
1812 
1813 	if (selinux_policycap_openperm)
1814 		av |= FILE__OPEN;
1815 
1816 	return av;
1817 }
1818 
1819 /* Hook functions begin here. */
1820 
1821 static int selinux_ptrace_access_check(struct task_struct *child,
1822 				     unsigned int mode)
1823 {
1824 	int rc;
1825 
1826 	rc = cap_ptrace_access_check(child, mode);
1827 	if (rc)
1828 		return rc;
1829 
1830 	if (mode & PTRACE_MODE_READ) {
1831 		u32 sid = current_sid();
1832 		u32 csid = task_sid(child);
1833 		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1834 	}
1835 
1836 	return current_has_perm(child, PROCESS__PTRACE);
1837 }
1838 
1839 static int selinux_ptrace_traceme(struct task_struct *parent)
1840 {
1841 	int rc;
1842 
1843 	rc = cap_ptrace_traceme(parent);
1844 	if (rc)
1845 		return rc;
1846 
1847 	return task_has_perm(parent, current, PROCESS__PTRACE);
1848 }
1849 
1850 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1851 			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
1852 {
1853 	int error;
1854 
1855 	error = current_has_perm(target, PROCESS__GETCAP);
1856 	if (error)
1857 		return error;
1858 
1859 	return cap_capget(target, effective, inheritable, permitted);
1860 }
1861 
1862 static int selinux_capset(struct cred *new, const struct cred *old,
1863 			  const kernel_cap_t *effective,
1864 			  const kernel_cap_t *inheritable,
1865 			  const kernel_cap_t *permitted)
1866 {
1867 	int error;
1868 
1869 	error = cap_capset(new, old,
1870 				      effective, inheritable, permitted);
1871 	if (error)
1872 		return error;
1873 
1874 	return cred_has_perm(old, new, PROCESS__SETCAP);
1875 }
1876 
1877 /*
1878  * (This comment used to live with the selinux_task_setuid hook,
1879  * which was removed).
1880  *
1881  * Since setuid only affects the current process, and since the SELinux
1882  * controls are not based on the Linux identity attributes, SELinux does not
1883  * need to control this operation.  However, SELinux does control the use of
1884  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1885  */
1886 
1887 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
1888 			   int cap, int audit)
1889 {
1890 	int rc;
1891 
1892 	rc = cap_capable(cred, ns, cap, audit);
1893 	if (rc)
1894 		return rc;
1895 
1896 	return cred_has_capability(cred, cap, audit);
1897 }
1898 
1899 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1900 {
1901 	const struct cred *cred = current_cred();
1902 	int rc = 0;
1903 
1904 	if (!sb)
1905 		return 0;
1906 
1907 	switch (cmds) {
1908 	case Q_SYNC:
1909 	case Q_QUOTAON:
1910 	case Q_QUOTAOFF:
1911 	case Q_SETINFO:
1912 	case Q_SETQUOTA:
1913 		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1914 		break;
1915 	case Q_GETFMT:
1916 	case Q_GETINFO:
1917 	case Q_GETQUOTA:
1918 		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1919 		break;
1920 	default:
1921 		rc = 0;  /* let the kernel handle invalid cmds */
1922 		break;
1923 	}
1924 	return rc;
1925 }
1926 
1927 static int selinux_quota_on(struct dentry *dentry)
1928 {
1929 	const struct cred *cred = current_cred();
1930 
1931 	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1932 }
1933 
1934 static int selinux_syslog(int type)
1935 {
1936 	int rc;
1937 
1938 	switch (type) {
1939 	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
1940 	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
1941 		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1942 		break;
1943 	case SYSLOG_ACTION_CONSOLE_OFF:	/* Disable logging to console */
1944 	case SYSLOG_ACTION_CONSOLE_ON:	/* Enable logging to console */
1945 	/* Set level of messages printed to console */
1946 	case SYSLOG_ACTION_CONSOLE_LEVEL:
1947 		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1948 		break;
1949 	case SYSLOG_ACTION_CLOSE:	/* Close log */
1950 	case SYSLOG_ACTION_OPEN:	/* Open log */
1951 	case SYSLOG_ACTION_READ:	/* Read from log */
1952 	case SYSLOG_ACTION_READ_CLEAR:	/* Read/clear last kernel messages */
1953 	case SYSLOG_ACTION_CLEAR:	/* Clear ring buffer */
1954 	default:
1955 		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1956 		break;
1957 	}
1958 	return rc;
1959 }
1960 
1961 /*
1962  * Check that a process has enough memory to allocate a new virtual
1963  * mapping. 0 means there is enough memory for the allocation to
1964  * succeed and -ENOMEM implies there is not.
1965  *
1966  * Do not audit the selinux permission check, as this is applied to all
1967  * processes that allocate mappings.
1968  */
1969 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1970 {
1971 	int rc, cap_sys_admin = 0;
1972 
1973 	rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
1974 			     SECURITY_CAP_NOAUDIT);
1975 	if (rc == 0)
1976 		cap_sys_admin = 1;
1977 
1978 	return __vm_enough_memory(mm, pages, cap_sys_admin);
1979 }
1980 
1981 /* binprm security operations */
1982 
1983 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1984 {
1985 	const struct task_security_struct *old_tsec;
1986 	struct task_security_struct *new_tsec;
1987 	struct inode_security_struct *isec;
1988 	struct common_audit_data ad;
1989 	struct selinux_audit_data sad = {0,};
1990 	struct inode *inode = bprm->file->f_path.dentry->d_inode;
1991 	int rc;
1992 
1993 	rc = cap_bprm_set_creds(bprm);
1994 	if (rc)
1995 		return rc;
1996 
1997 	/* SELinux context only depends on initial program or script and not
1998 	 * the script interpreter */
1999 	if (bprm->cred_prepared)
2000 		return 0;
2001 
2002 	old_tsec = current_security();
2003 	new_tsec = bprm->cred->security;
2004 	isec = inode->i_security;
2005 
2006 	/* Default to the current task SID. */
2007 	new_tsec->sid = old_tsec->sid;
2008 	new_tsec->osid = old_tsec->sid;
2009 
2010 	/* Reset fs, key, and sock SIDs on execve. */
2011 	new_tsec->create_sid = 0;
2012 	new_tsec->keycreate_sid = 0;
2013 	new_tsec->sockcreate_sid = 0;
2014 
2015 	if (old_tsec->exec_sid) {
2016 		new_tsec->sid = old_tsec->exec_sid;
2017 		/* Reset exec SID on execve. */
2018 		new_tsec->exec_sid = 0;
2019 
2020 		/*
2021 		 * Minimize confusion: if no_new_privs and a transition is
2022 		 * explicitly requested, then fail the exec.
2023 		 */
2024 		if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
2025 			return -EPERM;
2026 	} else {
2027 		/* Check for a default transition on this program. */
2028 		rc = security_transition_sid(old_tsec->sid, isec->sid,
2029 					     SECCLASS_PROCESS, NULL,
2030 					     &new_tsec->sid);
2031 		if (rc)
2032 			return rc;
2033 	}
2034 
2035 	COMMON_AUDIT_DATA_INIT(&ad, PATH);
2036 	ad.selinux_audit_data = &sad;
2037 	ad.u.path = bprm->file->f_path;
2038 
2039 	if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
2040 	    (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2041 		new_tsec->sid = old_tsec->sid;
2042 
2043 	if (new_tsec->sid == old_tsec->sid) {
2044 		rc = avc_has_perm(old_tsec->sid, isec->sid,
2045 				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2046 		if (rc)
2047 			return rc;
2048 	} else {
2049 		/* Check permissions for the transition. */
2050 		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2051 				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2052 		if (rc)
2053 			return rc;
2054 
2055 		rc = avc_has_perm(new_tsec->sid, isec->sid,
2056 				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2057 		if (rc)
2058 			return rc;
2059 
2060 		/* Check for shared state */
2061 		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2062 			rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2063 					  SECCLASS_PROCESS, PROCESS__SHARE,
2064 					  NULL);
2065 			if (rc)
2066 				return -EPERM;
2067 		}
2068 
2069 		/* Make sure that anyone attempting to ptrace over a task that
2070 		 * changes its SID has the appropriate permit */
2071 		if (bprm->unsafe &
2072 		    (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2073 			struct task_struct *tracer;
2074 			struct task_security_struct *sec;
2075 			u32 ptsid = 0;
2076 
2077 			rcu_read_lock();
2078 			tracer = ptrace_parent(current);
2079 			if (likely(tracer != NULL)) {
2080 				sec = __task_cred(tracer)->security;
2081 				ptsid = sec->sid;
2082 			}
2083 			rcu_read_unlock();
2084 
2085 			if (ptsid != 0) {
2086 				rc = avc_has_perm(ptsid, new_tsec->sid,
2087 						  SECCLASS_PROCESS,
2088 						  PROCESS__PTRACE, NULL);
2089 				if (rc)
2090 					return -EPERM;
2091 			}
2092 		}
2093 
2094 		/* Clear any possibly unsafe personality bits on exec: */
2095 		bprm->per_clear |= PER_CLEAR_ON_SETID;
2096 	}
2097 
2098 	return 0;
2099 }
2100 
2101 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2102 {
2103 	const struct task_security_struct *tsec = current_security();
2104 	u32 sid, osid;
2105 	int atsecure = 0;
2106 
2107 	sid = tsec->sid;
2108 	osid = tsec->osid;
2109 
2110 	if (osid != sid) {
2111 		/* Enable secure mode for SIDs transitions unless
2112 		   the noatsecure permission is granted between
2113 		   the two SIDs, i.e. ahp returns 0. */
2114 		atsecure = avc_has_perm(osid, sid,
2115 					SECCLASS_PROCESS,
2116 					PROCESS__NOATSECURE, NULL);
2117 	}
2118 
2119 	return (atsecure || cap_bprm_secureexec(bprm));
2120 }
2121 
2122 /* Derived from fs/exec.c:flush_old_files. */
2123 static inline void flush_unauthorized_files(const struct cred *cred,
2124 					    struct files_struct *files)
2125 {
2126 	struct common_audit_data ad;
2127 	struct selinux_audit_data sad = {0,};
2128 	struct file *file, *devnull = NULL;
2129 	struct tty_struct *tty;
2130 	struct fdtable *fdt;
2131 	long j = -1;
2132 	int drop_tty = 0;
2133 
2134 	tty = get_current_tty();
2135 	if (tty) {
2136 		spin_lock(&tty_files_lock);
2137 		if (!list_empty(&tty->tty_files)) {
2138 			struct tty_file_private *file_priv;
2139 			struct inode *inode;
2140 
2141 			/* Revalidate access to controlling tty.
2142 			   Use inode_has_perm on the tty inode directly rather
2143 			   than using file_has_perm, as this particular open
2144 			   file may belong to another process and we are only
2145 			   interested in the inode-based check here. */
2146 			file_priv = list_first_entry(&tty->tty_files,
2147 						struct tty_file_private, list);
2148 			file = file_priv->file;
2149 			inode = file->f_path.dentry->d_inode;
2150 			if (inode_has_perm_noadp(cred, inode,
2151 					   FILE__READ | FILE__WRITE, 0)) {
2152 				drop_tty = 1;
2153 			}
2154 		}
2155 		spin_unlock(&tty_files_lock);
2156 		tty_kref_put(tty);
2157 	}
2158 	/* Reset controlling tty. */
2159 	if (drop_tty)
2160 		no_tty();
2161 
2162 	/* Revalidate access to inherited open files. */
2163 
2164 	COMMON_AUDIT_DATA_INIT(&ad, INODE);
2165 	ad.selinux_audit_data = &sad;
2166 
2167 	spin_lock(&files->file_lock);
2168 	for (;;) {
2169 		unsigned long set, i;
2170 		int fd;
2171 
2172 		j++;
2173 		i = j * __NFDBITS;
2174 		fdt = files_fdtable(files);
2175 		if (i >= fdt->max_fds)
2176 			break;
2177 		set = fdt->open_fds[j];
2178 		if (!set)
2179 			continue;
2180 		spin_unlock(&files->file_lock);
2181 		for ( ; set ; i++, set >>= 1) {
2182 			if (set & 1) {
2183 				file = fget(i);
2184 				if (!file)
2185 					continue;
2186 				if (file_has_perm(cred,
2187 						  file,
2188 						  file_to_av(file))) {
2189 					sys_close(i);
2190 					fd = get_unused_fd();
2191 					if (fd != i) {
2192 						if (fd >= 0)
2193 							put_unused_fd(fd);
2194 						fput(file);
2195 						continue;
2196 					}
2197 					if (devnull) {
2198 						get_file(devnull);
2199 					} else {
2200 						devnull = dentry_open(
2201 							dget(selinux_null),
2202 							mntget(selinuxfs_mount),
2203 							O_RDWR, cred);
2204 						if (IS_ERR(devnull)) {
2205 							devnull = NULL;
2206 							put_unused_fd(fd);
2207 							fput(file);
2208 							continue;
2209 						}
2210 					}
2211 					fd_install(fd, devnull);
2212 				}
2213 				fput(file);
2214 			}
2215 		}
2216 		spin_lock(&files->file_lock);
2217 
2218 	}
2219 	spin_unlock(&files->file_lock);
2220 }
2221 
2222 /*
2223  * Prepare a process for imminent new credential changes due to exec
2224  */
2225 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2226 {
2227 	struct task_security_struct *new_tsec;
2228 	struct rlimit *rlim, *initrlim;
2229 	int rc, i;
2230 
2231 	new_tsec = bprm->cred->security;
2232 	if (new_tsec->sid == new_tsec->osid)
2233 		return;
2234 
2235 	/* Close files for which the new task SID is not authorized. */
2236 	flush_unauthorized_files(bprm->cred, current->files);
2237 
2238 	/* Always clear parent death signal on SID transitions. */
2239 	current->pdeath_signal = 0;
2240 
2241 	/* Check whether the new SID can inherit resource limits from the old
2242 	 * SID.  If not, reset all soft limits to the lower of the current
2243 	 * task's hard limit and the init task's soft limit.
2244 	 *
2245 	 * Note that the setting of hard limits (even to lower them) can be
2246 	 * controlled by the setrlimit check.  The inclusion of the init task's
2247 	 * soft limit into the computation is to avoid resetting soft limits
2248 	 * higher than the default soft limit for cases where the default is
2249 	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2250 	 */
2251 	rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2252 			  PROCESS__RLIMITINH, NULL);
2253 	if (rc) {
2254 		/* protect against do_prlimit() */
2255 		task_lock(current);
2256 		for (i = 0; i < RLIM_NLIMITS; i++) {
2257 			rlim = current->signal->rlim + i;
2258 			initrlim = init_task.signal->rlim + i;
2259 			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2260 		}
2261 		task_unlock(current);
2262 		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2263 	}
2264 }
2265 
2266 /*
2267  * Clean up the process immediately after the installation of new credentials
2268  * due to exec
2269  */
2270 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2271 {
2272 	const struct task_security_struct *tsec = current_security();
2273 	struct itimerval itimer;
2274 	u32 osid, sid;
2275 	int rc, i;
2276 
2277 	osid = tsec->osid;
2278 	sid = tsec->sid;
2279 
2280 	if (sid == osid)
2281 		return;
2282 
2283 	/* Check whether the new SID can inherit signal state from the old SID.
2284 	 * If not, clear itimers to avoid subsequent signal generation and
2285 	 * flush and unblock signals.
2286 	 *
2287 	 * This must occur _after_ the task SID has been updated so that any
2288 	 * kill done after the flush will be checked against the new SID.
2289 	 */
2290 	rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2291 	if (rc) {
2292 		memset(&itimer, 0, sizeof itimer);
2293 		for (i = 0; i < 3; i++)
2294 			do_setitimer(i, &itimer, NULL);
2295 		spin_lock_irq(&current->sighand->siglock);
2296 		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2297 			__flush_signals(current);
2298 			flush_signal_handlers(current, 1);
2299 			sigemptyset(&current->blocked);
2300 		}
2301 		spin_unlock_irq(&current->sighand->siglock);
2302 	}
2303 
2304 	/* Wake up the parent if it is waiting so that it can recheck
2305 	 * wait permission to the new task SID. */
2306 	read_lock(&tasklist_lock);
2307 	__wake_up_parent(current, current->real_parent);
2308 	read_unlock(&tasklist_lock);
2309 }
2310 
2311 /* superblock security operations */
2312 
2313 static int selinux_sb_alloc_security(struct super_block *sb)
2314 {
2315 	return superblock_alloc_security(sb);
2316 }
2317 
2318 static void selinux_sb_free_security(struct super_block *sb)
2319 {
2320 	superblock_free_security(sb);
2321 }
2322 
2323 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2324 {
2325 	if (plen > olen)
2326 		return 0;
2327 
2328 	return !memcmp(prefix, option, plen);
2329 }
2330 
2331 static inline int selinux_option(char *option, int len)
2332 {
2333 	return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2334 		match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2335 		match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2336 		match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2337 		match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2338 }
2339 
2340 static inline void take_option(char **to, char *from, int *first, int len)
2341 {
2342 	if (!*first) {
2343 		**to = ',';
2344 		*to += 1;
2345 	} else
2346 		*first = 0;
2347 	memcpy(*to, from, len);
2348 	*to += len;
2349 }
2350 
2351 static inline void take_selinux_option(char **to, char *from, int *first,
2352 				       int len)
2353 {
2354 	int current_size = 0;
2355 
2356 	if (!*first) {
2357 		**to = '|';
2358 		*to += 1;
2359 	} else
2360 		*first = 0;
2361 
2362 	while (current_size < len) {
2363 		if (*from != '"') {
2364 			**to = *from;
2365 			*to += 1;
2366 		}
2367 		from += 1;
2368 		current_size += 1;
2369 	}
2370 }
2371 
2372 static int selinux_sb_copy_data(char *orig, char *copy)
2373 {
2374 	int fnosec, fsec, rc = 0;
2375 	char *in_save, *in_curr, *in_end;
2376 	char *sec_curr, *nosec_save, *nosec;
2377 	int open_quote = 0;
2378 
2379 	in_curr = orig;
2380 	sec_curr = copy;
2381 
2382 	nosec = (char *)get_zeroed_page(GFP_KERNEL);
2383 	if (!nosec) {
2384 		rc = -ENOMEM;
2385 		goto out;
2386 	}
2387 
2388 	nosec_save = nosec;
2389 	fnosec = fsec = 1;
2390 	in_save = in_end = orig;
2391 
2392 	do {
2393 		if (*in_end == '"')
2394 			open_quote = !open_quote;
2395 		if ((*in_end == ',' && open_quote == 0) ||
2396 				*in_end == '\0') {
2397 			int len = in_end - in_curr;
2398 
2399 			if (selinux_option(in_curr, len))
2400 				take_selinux_option(&sec_curr, in_curr, &fsec, len);
2401 			else
2402 				take_option(&nosec, in_curr, &fnosec, len);
2403 
2404 			in_curr = in_end + 1;
2405 		}
2406 	} while (*in_end++);
2407 
2408 	strcpy(in_save, nosec_save);
2409 	free_page((unsigned long)nosec_save);
2410 out:
2411 	return rc;
2412 }
2413 
2414 static int selinux_sb_remount(struct super_block *sb, void *data)
2415 {
2416 	int rc, i, *flags;
2417 	struct security_mnt_opts opts;
2418 	char *secdata, **mount_options;
2419 	struct superblock_security_struct *sbsec = sb->s_security;
2420 
2421 	if (!(sbsec->flags & SE_SBINITIALIZED))
2422 		return 0;
2423 
2424 	if (!data)
2425 		return 0;
2426 
2427 	if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2428 		return 0;
2429 
2430 	security_init_mnt_opts(&opts);
2431 	secdata = alloc_secdata();
2432 	if (!secdata)
2433 		return -ENOMEM;
2434 	rc = selinux_sb_copy_data(data, secdata);
2435 	if (rc)
2436 		goto out_free_secdata;
2437 
2438 	rc = selinux_parse_opts_str(secdata, &opts);
2439 	if (rc)
2440 		goto out_free_secdata;
2441 
2442 	mount_options = opts.mnt_opts;
2443 	flags = opts.mnt_opts_flags;
2444 
2445 	for (i = 0; i < opts.num_mnt_opts; i++) {
2446 		u32 sid;
2447 		size_t len;
2448 
2449 		if (flags[i] == SE_SBLABELSUPP)
2450 			continue;
2451 		len = strlen(mount_options[i]);
2452 		rc = security_context_to_sid(mount_options[i], len, &sid);
2453 		if (rc) {
2454 			printk(KERN_WARNING "SELinux: security_context_to_sid"
2455 			       "(%s) failed for (dev %s, type %s) errno=%d\n",
2456 			       mount_options[i], sb->s_id, sb->s_type->name, rc);
2457 			goto out_free_opts;
2458 		}
2459 		rc = -EINVAL;
2460 		switch (flags[i]) {
2461 		case FSCONTEXT_MNT:
2462 			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2463 				goto out_bad_option;
2464 			break;
2465 		case CONTEXT_MNT:
2466 			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2467 				goto out_bad_option;
2468 			break;
2469 		case ROOTCONTEXT_MNT: {
2470 			struct inode_security_struct *root_isec;
2471 			root_isec = sb->s_root->d_inode->i_security;
2472 
2473 			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2474 				goto out_bad_option;
2475 			break;
2476 		}
2477 		case DEFCONTEXT_MNT:
2478 			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2479 				goto out_bad_option;
2480 			break;
2481 		default:
2482 			goto out_free_opts;
2483 		}
2484 	}
2485 
2486 	rc = 0;
2487 out_free_opts:
2488 	security_free_mnt_opts(&opts);
2489 out_free_secdata:
2490 	free_secdata(secdata);
2491 	return rc;
2492 out_bad_option:
2493 	printk(KERN_WARNING "SELinux: unable to change security options "
2494 	       "during remount (dev %s, type=%s)\n", sb->s_id,
2495 	       sb->s_type->name);
2496 	goto out_free_opts;
2497 }
2498 
2499 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2500 {
2501 	const struct cred *cred = current_cred();
2502 	struct common_audit_data ad;
2503 	struct selinux_audit_data sad = {0,};
2504 	int rc;
2505 
2506 	rc = superblock_doinit(sb, data);
2507 	if (rc)
2508 		return rc;
2509 
2510 	/* Allow all mounts performed by the kernel */
2511 	if (flags & MS_KERNMOUNT)
2512 		return 0;
2513 
2514 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2515 	ad.selinux_audit_data = &sad;
2516 	ad.u.dentry = sb->s_root;
2517 	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2518 }
2519 
2520 static int selinux_sb_statfs(struct dentry *dentry)
2521 {
2522 	const struct cred *cred = current_cred();
2523 	struct common_audit_data ad;
2524 	struct selinux_audit_data sad = {0,};
2525 
2526 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2527 	ad.selinux_audit_data = &sad;
2528 	ad.u.dentry = dentry->d_sb->s_root;
2529 	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2530 }
2531 
2532 static int selinux_mount(char *dev_name,
2533 			 struct path *path,
2534 			 char *type,
2535 			 unsigned long flags,
2536 			 void *data)
2537 {
2538 	const struct cred *cred = current_cred();
2539 
2540 	if (flags & MS_REMOUNT)
2541 		return superblock_has_perm(cred, path->dentry->d_sb,
2542 					   FILESYSTEM__REMOUNT, NULL);
2543 	else
2544 		return path_has_perm(cred, path, FILE__MOUNTON);
2545 }
2546 
2547 static int selinux_umount(struct vfsmount *mnt, int flags)
2548 {
2549 	const struct cred *cred = current_cred();
2550 
2551 	return superblock_has_perm(cred, mnt->mnt_sb,
2552 				   FILESYSTEM__UNMOUNT, NULL);
2553 }
2554 
2555 /* inode security operations */
2556 
2557 static int selinux_inode_alloc_security(struct inode *inode)
2558 {
2559 	return inode_alloc_security(inode);
2560 }
2561 
2562 static void selinux_inode_free_security(struct inode *inode)
2563 {
2564 	inode_free_security(inode);
2565 }
2566 
2567 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2568 				       const struct qstr *qstr, char **name,
2569 				       void **value, size_t *len)
2570 {
2571 	const struct task_security_struct *tsec = current_security();
2572 	struct inode_security_struct *dsec;
2573 	struct superblock_security_struct *sbsec;
2574 	u32 sid, newsid, clen;
2575 	int rc;
2576 	char *namep = NULL, *context;
2577 
2578 	dsec = dir->i_security;
2579 	sbsec = dir->i_sb->s_security;
2580 
2581 	sid = tsec->sid;
2582 	newsid = tsec->create_sid;
2583 
2584 	if ((sbsec->flags & SE_SBINITIALIZED) &&
2585 	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2586 		newsid = sbsec->mntpoint_sid;
2587 	else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2588 		rc = security_transition_sid(sid, dsec->sid,
2589 					     inode_mode_to_security_class(inode->i_mode),
2590 					     qstr, &newsid);
2591 		if (rc) {
2592 			printk(KERN_WARNING "%s:  "
2593 			       "security_transition_sid failed, rc=%d (dev=%s "
2594 			       "ino=%ld)\n",
2595 			       __func__,
2596 			       -rc, inode->i_sb->s_id, inode->i_ino);
2597 			return rc;
2598 		}
2599 	}
2600 
2601 	/* Possibly defer initialization to selinux_complete_init. */
2602 	if (sbsec->flags & SE_SBINITIALIZED) {
2603 		struct inode_security_struct *isec = inode->i_security;
2604 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
2605 		isec->sid = newsid;
2606 		isec->initialized = 1;
2607 	}
2608 
2609 	if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2610 		return -EOPNOTSUPP;
2611 
2612 	if (name) {
2613 		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2614 		if (!namep)
2615 			return -ENOMEM;
2616 		*name = namep;
2617 	}
2618 
2619 	if (value && len) {
2620 		rc = security_sid_to_context_force(newsid, &context, &clen);
2621 		if (rc) {
2622 			kfree(namep);
2623 			return rc;
2624 		}
2625 		*value = context;
2626 		*len = clen;
2627 	}
2628 
2629 	return 0;
2630 }
2631 
2632 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2633 {
2634 	return may_create(dir, dentry, SECCLASS_FILE);
2635 }
2636 
2637 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2638 {
2639 	return may_link(dir, old_dentry, MAY_LINK);
2640 }
2641 
2642 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2643 {
2644 	return may_link(dir, dentry, MAY_UNLINK);
2645 }
2646 
2647 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2648 {
2649 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
2650 }
2651 
2652 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2653 {
2654 	return may_create(dir, dentry, SECCLASS_DIR);
2655 }
2656 
2657 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2658 {
2659 	return may_link(dir, dentry, MAY_RMDIR);
2660 }
2661 
2662 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2663 {
2664 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
2665 }
2666 
2667 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2668 				struct inode *new_inode, struct dentry *new_dentry)
2669 {
2670 	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2671 }
2672 
2673 static int selinux_inode_readlink(struct dentry *dentry)
2674 {
2675 	const struct cred *cred = current_cred();
2676 
2677 	return dentry_has_perm(cred, dentry, FILE__READ);
2678 }
2679 
2680 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2681 {
2682 	const struct cred *cred = current_cred();
2683 
2684 	return dentry_has_perm(cred, dentry, FILE__READ);
2685 }
2686 
2687 static int selinux_inode_permission(struct inode *inode, int mask)
2688 {
2689 	const struct cred *cred = current_cred();
2690 	struct common_audit_data ad;
2691 	struct selinux_audit_data sad = {0,};
2692 	u32 perms;
2693 	bool from_access;
2694 	unsigned flags = mask & MAY_NOT_BLOCK;
2695 
2696 	from_access = mask & MAY_ACCESS;
2697 	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2698 
2699 	/* No permission to check.  Existence test. */
2700 	if (!mask)
2701 		return 0;
2702 
2703 	COMMON_AUDIT_DATA_INIT(&ad, INODE);
2704 	ad.selinux_audit_data = &sad;
2705 	ad.u.inode = inode;
2706 
2707 	if (from_access)
2708 		ad.selinux_audit_data->auditdeny |= FILE__AUDIT_ACCESS;
2709 
2710 	perms = file_mask_to_av(inode->i_mode, mask);
2711 
2712 	return inode_has_perm(cred, inode, perms, &ad, flags);
2713 }
2714 
2715 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2716 {
2717 	const struct cred *cred = current_cred();
2718 	unsigned int ia_valid = iattr->ia_valid;
2719 
2720 	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2721 	if (ia_valid & ATTR_FORCE) {
2722 		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2723 			      ATTR_FORCE);
2724 		if (!ia_valid)
2725 			return 0;
2726 	}
2727 
2728 	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2729 			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2730 		return dentry_has_perm(cred, dentry, FILE__SETATTR);
2731 
2732 	return dentry_has_perm(cred, dentry, FILE__WRITE);
2733 }
2734 
2735 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2736 {
2737 	const struct cred *cred = current_cred();
2738 	struct path path;
2739 
2740 	path.dentry = dentry;
2741 	path.mnt = mnt;
2742 
2743 	return path_has_perm(cred, &path, FILE__GETATTR);
2744 }
2745 
2746 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2747 {
2748 	const struct cred *cred = current_cred();
2749 
2750 	if (!strncmp(name, XATTR_SECURITY_PREFIX,
2751 		     sizeof XATTR_SECURITY_PREFIX - 1)) {
2752 		if (!strcmp(name, XATTR_NAME_CAPS)) {
2753 			if (!capable(CAP_SETFCAP))
2754 				return -EPERM;
2755 		} else if (!capable(CAP_SYS_ADMIN)) {
2756 			/* A different attribute in the security namespace.
2757 			   Restrict to administrator. */
2758 			return -EPERM;
2759 		}
2760 	}
2761 
2762 	/* Not an attribute we recognize, so just check the
2763 	   ordinary setattr permission. */
2764 	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2765 }
2766 
2767 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2768 				  const void *value, size_t size, int flags)
2769 {
2770 	struct inode *inode = dentry->d_inode;
2771 	struct inode_security_struct *isec = inode->i_security;
2772 	struct superblock_security_struct *sbsec;
2773 	struct common_audit_data ad;
2774 	struct selinux_audit_data sad = {0,};
2775 	u32 newsid, sid = current_sid();
2776 	int rc = 0;
2777 
2778 	if (strcmp(name, XATTR_NAME_SELINUX))
2779 		return selinux_inode_setotherxattr(dentry, name);
2780 
2781 	sbsec = inode->i_sb->s_security;
2782 	if (!(sbsec->flags & SE_SBLABELSUPP))
2783 		return -EOPNOTSUPP;
2784 
2785 	if (!inode_owner_or_capable(inode))
2786 		return -EPERM;
2787 
2788 	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2789 	ad.selinux_audit_data = &sad;
2790 	ad.u.dentry = dentry;
2791 
2792 	rc = avc_has_perm(sid, isec->sid, isec->sclass,
2793 			  FILE__RELABELFROM, &ad);
2794 	if (rc)
2795 		return rc;
2796 
2797 	rc = security_context_to_sid(value, size, &newsid);
2798 	if (rc == -EINVAL) {
2799 		if (!capable(CAP_MAC_ADMIN))
2800 			return rc;
2801 		rc = security_context_to_sid_force(value, size, &newsid);
2802 	}
2803 	if (rc)
2804 		return rc;
2805 
2806 	rc = avc_has_perm(sid, newsid, isec->sclass,
2807 			  FILE__RELABELTO, &ad);
2808 	if (rc)
2809 		return rc;
2810 
2811 	rc = security_validate_transition(isec->sid, newsid, sid,
2812 					  isec->sclass);
2813 	if (rc)
2814 		return rc;
2815 
2816 	return avc_has_perm(newsid,
2817 			    sbsec->sid,
2818 			    SECCLASS_FILESYSTEM,
2819 			    FILESYSTEM__ASSOCIATE,
2820 			    &ad);
2821 }
2822 
2823 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2824 					const void *value, size_t size,
2825 					int flags)
2826 {
2827 	struct inode *inode = dentry->d_inode;
2828 	struct inode_security_struct *isec = inode->i_security;
2829 	u32 newsid;
2830 	int rc;
2831 
2832 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2833 		/* Not an attribute we recognize, so nothing to do. */
2834 		return;
2835 	}
2836 
2837 	rc = security_context_to_sid_force(value, size, &newsid);
2838 	if (rc) {
2839 		printk(KERN_ERR "SELinux:  unable to map context to SID"
2840 		       "for (%s, %lu), rc=%d\n",
2841 		       inode->i_sb->s_id, inode->i_ino, -rc);
2842 		return;
2843 	}
2844 
2845 	isec->sid = newsid;
2846 	return;
2847 }
2848 
2849 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2850 {
2851 	const struct cred *cred = current_cred();
2852 
2853 	return dentry_has_perm(cred, dentry, FILE__GETATTR);
2854 }
2855 
2856 static int selinux_inode_listxattr(struct dentry *dentry)
2857 {
2858 	const struct cred *cred = current_cred();
2859 
2860 	return dentry_has_perm(cred, dentry, FILE__GETATTR);
2861 }
2862 
2863 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2864 {
2865 	if (strcmp(name, XATTR_NAME_SELINUX))
2866 		return selinux_inode_setotherxattr(dentry, name);
2867 
2868 	/* No one is allowed to remove a SELinux security label.
2869 	   You can change the label, but all data must be labeled. */
2870 	return -EACCES;
2871 }
2872 
2873 /*
2874  * Copy the inode security context value to the user.
2875  *
2876  * Permission check is handled by selinux_inode_getxattr hook.
2877  */
2878 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2879 {
2880 	u32 size;
2881 	int error;
2882 	char *context = NULL;
2883 	struct inode_security_struct *isec = inode->i_security;
2884 
2885 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
2886 		return -EOPNOTSUPP;
2887 
2888 	/*
2889 	 * If the caller has CAP_MAC_ADMIN, then get the raw context
2890 	 * value even if it is not defined by current policy; otherwise,
2891 	 * use the in-core value under current policy.
2892 	 * Use the non-auditing forms of the permission checks since
2893 	 * getxattr may be called by unprivileged processes commonly
2894 	 * and lack of permission just means that we fall back to the
2895 	 * in-core context value, not a denial.
2896 	 */
2897 	error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2898 				SECURITY_CAP_NOAUDIT);
2899 	if (!error)
2900 		error = security_sid_to_context_force(isec->sid, &context,
2901 						      &size);
2902 	else
2903 		error = security_sid_to_context(isec->sid, &context, &size);
2904 	if (error)
2905 		return error;
2906 	error = size;
2907 	if (alloc) {
2908 		*buffer = context;
2909 		goto out_nofree;
2910 	}
2911 	kfree(context);
2912 out_nofree:
2913 	return error;
2914 }
2915 
2916 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2917 				     const void *value, size_t size, int flags)
2918 {
2919 	struct inode_security_struct *isec = inode->i_security;
2920 	u32 newsid;
2921 	int rc;
2922 
2923 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
2924 		return -EOPNOTSUPP;
2925 
2926 	if (!value || !size)
2927 		return -EACCES;
2928 
2929 	rc = security_context_to_sid((void *)value, size, &newsid);
2930 	if (rc)
2931 		return rc;
2932 
2933 	isec->sid = newsid;
2934 	isec->initialized = 1;
2935 	return 0;
2936 }
2937 
2938 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2939 {
2940 	const int len = sizeof(XATTR_NAME_SELINUX);
2941 	if (buffer && len <= buffer_size)
2942 		memcpy(buffer, XATTR_NAME_SELINUX, len);
2943 	return len;
2944 }
2945 
2946 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2947 {
2948 	struct inode_security_struct *isec = inode->i_security;
2949 	*secid = isec->sid;
2950 }
2951 
2952 /* file security operations */
2953 
2954 static int selinux_revalidate_file_permission(struct file *file, int mask)
2955 {
2956 	const struct cred *cred = current_cred();
2957 	struct inode *inode = file->f_path.dentry->d_inode;
2958 
2959 	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2960 	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2961 		mask |= MAY_APPEND;
2962 
2963 	return file_has_perm(cred, file,
2964 			     file_mask_to_av(inode->i_mode, mask));
2965 }
2966 
2967 static int selinux_file_permission(struct file *file, int mask)
2968 {
2969 	struct inode *inode = file->f_path.dentry->d_inode;
2970 	struct file_security_struct *fsec = file->f_security;
2971 	struct inode_security_struct *isec = inode->i_security;
2972 	u32 sid = current_sid();
2973 
2974 	if (!mask)
2975 		/* No permission to check.  Existence test. */
2976 		return 0;
2977 
2978 	if (sid == fsec->sid && fsec->isid == isec->sid &&
2979 	    fsec->pseqno == avc_policy_seqno())
2980 		/* No change since dentry_open check. */
2981 		return 0;
2982 
2983 	return selinux_revalidate_file_permission(file, mask);
2984 }
2985 
2986 static int selinux_file_alloc_security(struct file *file)
2987 {
2988 	return file_alloc_security(file);
2989 }
2990 
2991 static void selinux_file_free_security(struct file *file)
2992 {
2993 	file_free_security(file);
2994 }
2995 
2996 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2997 			      unsigned long arg)
2998 {
2999 	const struct cred *cred = current_cred();
3000 	int error = 0;
3001 
3002 	switch (cmd) {
3003 	case FIONREAD:
3004 	/* fall through */
3005 	case FIBMAP:
3006 	/* fall through */
3007 	case FIGETBSZ:
3008 	/* fall through */
3009 	case FS_IOC_GETFLAGS:
3010 	/* fall through */
3011 	case FS_IOC_GETVERSION:
3012 		error = file_has_perm(cred, file, FILE__GETATTR);
3013 		break;
3014 
3015 	case FS_IOC_SETFLAGS:
3016 	/* fall through */
3017 	case FS_IOC_SETVERSION:
3018 		error = file_has_perm(cred, file, FILE__SETATTR);
3019 		break;
3020 
3021 	/* sys_ioctl() checks */
3022 	case FIONBIO:
3023 	/* fall through */
3024 	case FIOASYNC:
3025 		error = file_has_perm(cred, file, 0);
3026 		break;
3027 
3028 	case KDSKBENT:
3029 	case KDSKBSENT:
3030 		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3031 					    SECURITY_CAP_AUDIT);
3032 		break;
3033 
3034 	/* default case assumes that the command will go
3035 	 * to the file's ioctl() function.
3036 	 */
3037 	default:
3038 		error = file_has_perm(cred, file, FILE__IOCTL);
3039 	}
3040 	return error;
3041 }
3042 
3043 static int default_noexec;
3044 
3045 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3046 {
3047 	const struct cred *cred = current_cred();
3048 	int rc = 0;
3049 
3050 	if (default_noexec &&
3051 	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3052 		/*
3053 		 * We are making executable an anonymous mapping or a
3054 		 * private file mapping that will also be writable.
3055 		 * This has an additional check.
3056 		 */
3057 		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3058 		if (rc)
3059 			goto error;
3060 	}
3061 
3062 	if (file) {
3063 		/* read access is always possible with a mapping */
3064 		u32 av = FILE__READ;
3065 
3066 		/* write access only matters if the mapping is shared */
3067 		if (shared && (prot & PROT_WRITE))
3068 			av |= FILE__WRITE;
3069 
3070 		if (prot & PROT_EXEC)
3071 			av |= FILE__EXECUTE;
3072 
3073 		return file_has_perm(cred, file, av);
3074 	}
3075 
3076 error:
3077 	return rc;
3078 }
3079 
3080 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3081 			     unsigned long prot, unsigned long flags,
3082 			     unsigned long addr, unsigned long addr_only)
3083 {
3084 	int rc = 0;
3085 	u32 sid = current_sid();
3086 
3087 	/*
3088 	 * notice that we are intentionally putting the SELinux check before
3089 	 * the secondary cap_file_mmap check.  This is such a likely attempt
3090 	 * at bad behaviour/exploit that we always want to get the AVC, even
3091 	 * if DAC would have also denied the operation.
3092 	 */
3093 	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3094 		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3095 				  MEMPROTECT__MMAP_ZERO, NULL);
3096 		if (rc)
3097 			return rc;
3098 	}
3099 
3100 	/* do DAC check on address space usage */
3101 	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3102 	if (rc || addr_only)
3103 		return rc;
3104 
3105 	if (selinux_checkreqprot)
3106 		prot = reqprot;
3107 
3108 	return file_map_prot_check(file, prot,
3109 				   (flags & MAP_TYPE) == MAP_SHARED);
3110 }
3111 
3112 static int selinux_file_mprotect(struct vm_area_struct *vma,
3113 				 unsigned long reqprot,
3114 				 unsigned long prot)
3115 {
3116 	const struct cred *cred = current_cred();
3117 
3118 	if (selinux_checkreqprot)
3119 		prot = reqprot;
3120 
3121 	if (default_noexec &&
3122 	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3123 		int rc = 0;
3124 		if (vma->vm_start >= vma->vm_mm->start_brk &&
3125 		    vma->vm_end <= vma->vm_mm->brk) {
3126 			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3127 		} else if (!vma->vm_file &&
3128 			   vma->vm_start <= vma->vm_mm->start_stack &&
3129 			   vma->vm_end >= vma->vm_mm->start_stack) {
3130 			rc = current_has_perm(current, PROCESS__EXECSTACK);
3131 		} else if (vma->vm_file && vma->anon_vma) {
3132 			/*
3133 			 * We are making executable a file mapping that has
3134 			 * had some COW done. Since pages might have been
3135 			 * written, check ability to execute the possibly
3136 			 * modified content.  This typically should only
3137 			 * occur for text relocations.
3138 			 */
3139 			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3140 		}
3141 		if (rc)
3142 			return rc;
3143 	}
3144 
3145 	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3146 }
3147 
3148 static int selinux_file_lock(struct file *file, unsigned int cmd)
3149 {
3150 	const struct cred *cred = current_cred();
3151 
3152 	return file_has_perm(cred, file, FILE__LOCK);
3153 }
3154 
3155 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3156 			      unsigned long arg)
3157 {
3158 	const struct cred *cred = current_cred();
3159 	int err = 0;
3160 
3161 	switch (cmd) {
3162 	case F_SETFL:
3163 		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3164 			err = -EINVAL;
3165 			break;
3166 		}
3167 
3168 		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3169 			err = file_has_perm(cred, file, FILE__WRITE);
3170 			break;
3171 		}
3172 		/* fall through */
3173 	case F_SETOWN:
3174 	case F_SETSIG:
3175 	case F_GETFL:
3176 	case F_GETOWN:
3177 	case F_GETSIG:
3178 		/* Just check FD__USE permission */
3179 		err = file_has_perm(cred, file, 0);
3180 		break;
3181 	case F_GETLK:
3182 	case F_SETLK:
3183 	case F_SETLKW:
3184 #if BITS_PER_LONG == 32
3185 	case F_GETLK64:
3186 	case F_SETLK64:
3187 	case F_SETLKW64:
3188 #endif
3189 		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3190 			err = -EINVAL;
3191 			break;
3192 		}
3193 		err = file_has_perm(cred, file, FILE__LOCK);
3194 		break;
3195 	}
3196 
3197 	return err;
3198 }
3199 
3200 static int selinux_file_set_fowner(struct file *file)
3201 {
3202 	struct file_security_struct *fsec;
3203 
3204 	fsec = file->f_security;
3205 	fsec->fown_sid = current_sid();
3206 
3207 	return 0;
3208 }
3209 
3210 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3211 				       struct fown_struct *fown, int signum)
3212 {
3213 	struct file *file;
3214 	u32 sid = task_sid(tsk);
3215 	u32 perm;
3216 	struct file_security_struct *fsec;
3217 
3218 	/* struct fown_struct is never outside the context of a struct file */
3219 	file = container_of(fown, struct file, f_owner);
3220 
3221 	fsec = file->f_security;
3222 
3223 	if (!signum)
3224 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3225 	else
3226 		perm = signal_to_av(signum);
3227 
3228 	return avc_has_perm(fsec->fown_sid, sid,
3229 			    SECCLASS_PROCESS, perm, NULL);
3230 }
3231 
3232 static int selinux_file_receive(struct file *file)
3233 {
3234 	const struct cred *cred = current_cred();
3235 
3236 	return file_has_perm(cred, file, file_to_av(file));
3237 }
3238 
3239 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3240 {
3241 	struct file_security_struct *fsec;
3242 	struct inode *inode;
3243 	struct inode_security_struct *isec;
3244 
3245 	inode = file->f_path.dentry->d_inode;
3246 	fsec = file->f_security;
3247 	isec = inode->i_security;
3248 	/*
3249 	 * Save inode label and policy sequence number
3250 	 * at open-time so that selinux_file_permission
3251 	 * can determine whether revalidation is necessary.
3252 	 * Task label is already saved in the file security
3253 	 * struct as its SID.
3254 	 */
3255 	fsec->isid = isec->sid;
3256 	fsec->pseqno = avc_policy_seqno();
3257 	/*
3258 	 * Since the inode label or policy seqno may have changed
3259 	 * between the selinux_inode_permission check and the saving
3260 	 * of state above, recheck that access is still permitted.
3261 	 * Otherwise, access might never be revalidated against the
3262 	 * new inode label or new policy.
3263 	 * This check is not redundant - do not remove.
3264 	 */
3265 	return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3266 }
3267 
3268 /* task security operations */
3269 
3270 static int selinux_task_create(unsigned long clone_flags)
3271 {
3272 	return current_has_perm(current, PROCESS__FORK);
3273 }
3274 
3275 /*
3276  * allocate the SELinux part of blank credentials
3277  */
3278 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3279 {
3280 	struct task_security_struct *tsec;
3281 
3282 	tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3283 	if (!tsec)
3284 		return -ENOMEM;
3285 
3286 	cred->security = tsec;
3287 	return 0;
3288 }
3289 
3290 /*
3291  * detach and free the LSM part of a set of credentials
3292  */
3293 static void selinux_cred_free(struct cred *cred)
3294 {
3295 	struct task_security_struct *tsec = cred->security;
3296 
3297 	/*
3298 	 * cred->security == NULL if security_cred_alloc_blank() or
3299 	 * security_prepare_creds() returned an error.
3300 	 */
3301 	BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3302 	cred->security = (void *) 0x7UL;
3303 	kfree(tsec);
3304 }
3305 
3306 /*
3307  * prepare a new set of credentials for modification
3308  */
3309 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3310 				gfp_t gfp)
3311 {
3312 	const struct task_security_struct *old_tsec;
3313 	struct task_security_struct *tsec;
3314 
3315 	old_tsec = old->security;
3316 
3317 	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3318 	if (!tsec)
3319 		return -ENOMEM;
3320 
3321 	new->security = tsec;
3322 	return 0;
3323 }
3324 
3325 /*
3326  * transfer the SELinux data to a blank set of creds
3327  */
3328 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3329 {
3330 	const struct task_security_struct *old_tsec = old->security;
3331 	struct task_security_struct *tsec = new->security;
3332 
3333 	*tsec = *old_tsec;
3334 }
3335 
3336 /*
3337  * set the security data for a kernel service
3338  * - all the creation contexts are set to unlabelled
3339  */
3340 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3341 {
3342 	struct task_security_struct *tsec = new->security;
3343 	u32 sid = current_sid();
3344 	int ret;
3345 
3346 	ret = avc_has_perm(sid, secid,
3347 			   SECCLASS_KERNEL_SERVICE,
3348 			   KERNEL_SERVICE__USE_AS_OVERRIDE,
3349 			   NULL);
3350 	if (ret == 0) {
3351 		tsec->sid = secid;
3352 		tsec->create_sid = 0;
3353 		tsec->keycreate_sid = 0;
3354 		tsec->sockcreate_sid = 0;
3355 	}
3356 	return ret;
3357 }
3358 
3359 /*
3360  * set the file creation context in a security record to the same as the
3361  * objective context of the specified inode
3362  */
3363 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3364 {
3365 	struct inode_security_struct *isec = inode->i_security;
3366 	struct task_security_struct *tsec = new->security;
3367 	u32 sid = current_sid();
3368 	int ret;
3369 
3370 	ret = avc_has_perm(sid, isec->sid,
3371 			   SECCLASS_KERNEL_SERVICE,
3372 			   KERNEL_SERVICE__CREATE_FILES_AS,
3373 			   NULL);
3374 
3375 	if (ret == 0)
3376 		tsec->create_sid = isec->sid;
3377 	return ret;
3378 }
3379 
3380 static int selinux_kernel_module_request(char *kmod_name)
3381 {
3382 	u32 sid;
3383 	struct common_audit_data ad;
3384 	struct selinux_audit_data sad = {0,};
3385 
3386 	sid = task_sid(current);
3387 
3388 	COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3389 	ad.selinux_audit_data = &sad;
3390 	ad.u.kmod_name = kmod_name;
3391 
3392 	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3393 			    SYSTEM__MODULE_REQUEST, &ad);
3394 }
3395 
3396 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3397 {
3398 	return current_has_perm(p, PROCESS__SETPGID);
3399 }
3400 
3401 static int selinux_task_getpgid(struct task_struct *p)
3402 {
3403 	return current_has_perm(p, PROCESS__GETPGID);
3404 }
3405 
3406 static int selinux_task_getsid(struct task_struct *p)
3407 {
3408 	return current_has_perm(p, PROCESS__GETSESSION);
3409 }
3410 
3411 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3412 {
3413 	*secid = task_sid(p);
3414 }
3415 
3416 static int selinux_task_setnice(struct task_struct *p, int nice)
3417 {
3418 	int rc;
3419 
3420 	rc = cap_task_setnice(p, nice);
3421 	if (rc)
3422 		return rc;
3423 
3424 	return current_has_perm(p, PROCESS__SETSCHED);
3425 }
3426 
3427 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3428 {
3429 	int rc;
3430 
3431 	rc = cap_task_setioprio(p, ioprio);
3432 	if (rc)
3433 		return rc;
3434 
3435 	return current_has_perm(p, PROCESS__SETSCHED);
3436 }
3437 
3438 static int selinux_task_getioprio(struct task_struct *p)
3439 {
3440 	return current_has_perm(p, PROCESS__GETSCHED);
3441 }
3442 
3443 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3444 		struct rlimit *new_rlim)
3445 {
3446 	struct rlimit *old_rlim = p->signal->rlim + resource;
3447 
3448 	/* Control the ability to change the hard limit (whether
3449 	   lowering or raising it), so that the hard limit can
3450 	   later be used as a safe reset point for the soft limit
3451 	   upon context transitions.  See selinux_bprm_committing_creds. */
3452 	if (old_rlim->rlim_max != new_rlim->rlim_max)
3453 		return current_has_perm(p, PROCESS__SETRLIMIT);
3454 
3455 	return 0;
3456 }
3457 
3458 static int selinux_task_setscheduler(struct task_struct *p)
3459 {
3460 	int rc;
3461 
3462 	rc = cap_task_setscheduler(p);
3463 	if (rc)
3464 		return rc;
3465 
3466 	return current_has_perm(p, PROCESS__SETSCHED);
3467 }
3468 
3469 static int selinux_task_getscheduler(struct task_struct *p)
3470 {
3471 	return current_has_perm(p, PROCESS__GETSCHED);
3472 }
3473 
3474 static int selinux_task_movememory(struct task_struct *p)
3475 {
3476 	return current_has_perm(p, PROCESS__SETSCHED);
3477 }
3478 
3479 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3480 				int sig, u32 secid)
3481 {
3482 	u32 perm;
3483 	int rc;
3484 
3485 	if (!sig)
3486 		perm = PROCESS__SIGNULL; /* null signal; existence test */
3487 	else
3488 		perm = signal_to_av(sig);
3489 	if (secid)
3490 		rc = avc_has_perm(secid, task_sid(p),
3491 				  SECCLASS_PROCESS, perm, NULL);
3492 	else
3493 		rc = current_has_perm(p, perm);
3494 	return rc;
3495 }
3496 
3497 static int selinux_task_wait(struct task_struct *p)
3498 {
3499 	return task_has_perm(p, current, PROCESS__SIGCHLD);
3500 }
3501 
3502 static void selinux_task_to_inode(struct task_struct *p,
3503 				  struct inode *inode)
3504 {
3505 	struct inode_security_struct *isec = inode->i_security;
3506 	u32 sid = task_sid(p);
3507 
3508 	isec->sid = sid;
3509 	isec->initialized = 1;
3510 }
3511 
3512 /* Returns error only if unable to parse addresses */
3513 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3514 			struct common_audit_data *ad, u8 *proto)
3515 {
3516 	int offset, ihlen, ret = -EINVAL;
3517 	struct iphdr _iph, *ih;
3518 
3519 	offset = skb_network_offset(skb);
3520 	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3521 	if (ih == NULL)
3522 		goto out;
3523 
3524 	ihlen = ih->ihl * 4;
3525 	if (ihlen < sizeof(_iph))
3526 		goto out;
3527 
3528 	ad->u.net->v4info.saddr = ih->saddr;
3529 	ad->u.net->v4info.daddr = ih->daddr;
3530 	ret = 0;
3531 
3532 	if (proto)
3533 		*proto = ih->protocol;
3534 
3535 	switch (ih->protocol) {
3536 	case IPPROTO_TCP: {
3537 		struct tcphdr _tcph, *th;
3538 
3539 		if (ntohs(ih->frag_off) & IP_OFFSET)
3540 			break;
3541 
3542 		offset += ihlen;
3543 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3544 		if (th == NULL)
3545 			break;
3546 
3547 		ad->u.net->sport = th->source;
3548 		ad->u.net->dport = th->dest;
3549 		break;
3550 	}
3551 
3552 	case IPPROTO_UDP: {
3553 		struct udphdr _udph, *uh;
3554 
3555 		if (ntohs(ih->frag_off) & IP_OFFSET)
3556 			break;
3557 
3558 		offset += ihlen;
3559 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3560 		if (uh == NULL)
3561 			break;
3562 
3563 		ad->u.net->sport = uh->source;
3564 		ad->u.net->dport = uh->dest;
3565 		break;
3566 	}
3567 
3568 	case IPPROTO_DCCP: {
3569 		struct dccp_hdr _dccph, *dh;
3570 
3571 		if (ntohs(ih->frag_off) & IP_OFFSET)
3572 			break;
3573 
3574 		offset += ihlen;
3575 		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3576 		if (dh == NULL)
3577 			break;
3578 
3579 		ad->u.net->sport = dh->dccph_sport;
3580 		ad->u.net->dport = dh->dccph_dport;
3581 		break;
3582 	}
3583 
3584 	default:
3585 		break;
3586 	}
3587 out:
3588 	return ret;
3589 }
3590 
3591 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3592 
3593 /* Returns error only if unable to parse addresses */
3594 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3595 			struct common_audit_data *ad, u8 *proto)
3596 {
3597 	u8 nexthdr;
3598 	int ret = -EINVAL, offset;
3599 	struct ipv6hdr _ipv6h, *ip6;
3600 	__be16 frag_off;
3601 
3602 	offset = skb_network_offset(skb);
3603 	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3604 	if (ip6 == NULL)
3605 		goto out;
3606 
3607 	ad->u.net->v6info.saddr = ip6->saddr;
3608 	ad->u.net->v6info.daddr = ip6->daddr;
3609 	ret = 0;
3610 
3611 	nexthdr = ip6->nexthdr;
3612 	offset += sizeof(_ipv6h);
3613 	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3614 	if (offset < 0)
3615 		goto out;
3616 
3617 	if (proto)
3618 		*proto = nexthdr;
3619 
3620 	switch (nexthdr) {
3621 	case IPPROTO_TCP: {
3622 		struct tcphdr _tcph, *th;
3623 
3624 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3625 		if (th == NULL)
3626 			break;
3627 
3628 		ad->u.net->sport = th->source;
3629 		ad->u.net->dport = th->dest;
3630 		break;
3631 	}
3632 
3633 	case IPPROTO_UDP: {
3634 		struct udphdr _udph, *uh;
3635 
3636 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3637 		if (uh == NULL)
3638 			break;
3639 
3640 		ad->u.net->sport = uh->source;
3641 		ad->u.net->dport = uh->dest;
3642 		break;
3643 	}
3644 
3645 	case IPPROTO_DCCP: {
3646 		struct dccp_hdr _dccph, *dh;
3647 
3648 		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3649 		if (dh == NULL)
3650 			break;
3651 
3652 		ad->u.net->sport = dh->dccph_sport;
3653 		ad->u.net->dport = dh->dccph_dport;
3654 		break;
3655 	}
3656 
3657 	/* includes fragments */
3658 	default:
3659 		break;
3660 	}
3661 out:
3662 	return ret;
3663 }
3664 
3665 #endif /* IPV6 */
3666 
3667 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3668 			     char **_addrp, int src, u8 *proto)
3669 {
3670 	char *addrp;
3671 	int ret;
3672 
3673 	switch (ad->u.net->family) {
3674 	case PF_INET:
3675 		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3676 		if (ret)
3677 			goto parse_error;
3678 		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3679 				       &ad->u.net->v4info.daddr);
3680 		goto okay;
3681 
3682 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3683 	case PF_INET6:
3684 		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3685 		if (ret)
3686 			goto parse_error;
3687 		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3688 				       &ad->u.net->v6info.daddr);
3689 		goto okay;
3690 #endif	/* IPV6 */
3691 	default:
3692 		addrp = NULL;
3693 		goto okay;
3694 	}
3695 
3696 parse_error:
3697 	printk(KERN_WARNING
3698 	       "SELinux: failure in selinux_parse_skb(),"
3699 	       " unable to parse packet\n");
3700 	return ret;
3701 
3702 okay:
3703 	if (_addrp)
3704 		*_addrp = addrp;
3705 	return 0;
3706 }
3707 
3708 /**
3709  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3710  * @skb: the packet
3711  * @family: protocol family
3712  * @sid: the packet's peer label SID
3713  *
3714  * Description:
3715  * Check the various different forms of network peer labeling and determine
3716  * the peer label/SID for the packet; most of the magic actually occurs in
3717  * the security server function security_net_peersid_cmp().  The function
3718  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3719  * or -EACCES if @sid is invalid due to inconsistencies with the different
3720  * peer labels.
3721  *
3722  */
3723 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3724 {
3725 	int err;
3726 	u32 xfrm_sid;
3727 	u32 nlbl_sid;
3728 	u32 nlbl_type;
3729 
3730 	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3731 	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3732 
3733 	err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3734 	if (unlikely(err)) {
3735 		printk(KERN_WARNING
3736 		       "SELinux: failure in selinux_skb_peerlbl_sid(),"
3737 		       " unable to determine packet's peer label\n");
3738 		return -EACCES;
3739 	}
3740 
3741 	return 0;
3742 }
3743 
3744 /* socket security operations */
3745 
3746 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3747 				 u16 secclass, u32 *socksid)
3748 {
3749 	if (tsec->sockcreate_sid > SECSID_NULL) {
3750 		*socksid = tsec->sockcreate_sid;
3751 		return 0;
3752 	}
3753 
3754 	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3755 				       socksid);
3756 }
3757 
3758 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3759 {
3760 	struct sk_security_struct *sksec = sk->sk_security;
3761 	struct common_audit_data ad;
3762 	struct selinux_audit_data sad = {0,};
3763 	struct lsm_network_audit net = {0,};
3764 	u32 tsid = task_sid(task);
3765 
3766 	if (sksec->sid == SECINITSID_KERNEL)
3767 		return 0;
3768 
3769 	COMMON_AUDIT_DATA_INIT(&ad, NET);
3770 	ad.selinux_audit_data = &sad;
3771 	ad.u.net = &net;
3772 	ad.u.net->sk = sk;
3773 
3774 	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3775 }
3776 
3777 static int selinux_socket_create(int family, int type,
3778 				 int protocol, int kern)
3779 {
3780 	const struct task_security_struct *tsec = current_security();
3781 	u32 newsid;
3782 	u16 secclass;
3783 	int rc;
3784 
3785 	if (kern)
3786 		return 0;
3787 
3788 	secclass = socket_type_to_security_class(family, type, protocol);
3789 	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3790 	if (rc)
3791 		return rc;
3792 
3793 	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3794 }
3795 
3796 static int selinux_socket_post_create(struct socket *sock, int family,
3797 				      int type, int protocol, int kern)
3798 {
3799 	const struct task_security_struct *tsec = current_security();
3800 	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3801 	struct sk_security_struct *sksec;
3802 	int err = 0;
3803 
3804 	isec->sclass = socket_type_to_security_class(family, type, protocol);
3805 
3806 	if (kern)
3807 		isec->sid = SECINITSID_KERNEL;
3808 	else {
3809 		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3810 		if (err)
3811 			return err;
3812 	}
3813 
3814 	isec->initialized = 1;
3815 
3816 	if (sock->sk) {
3817 		sksec = sock->sk->sk_security;
3818 		sksec->sid = isec->sid;
3819 		sksec->sclass = isec->sclass;
3820 		err = selinux_netlbl_socket_post_create(sock->sk, family);
3821 	}
3822 
3823 	return err;
3824 }
3825 
3826 /* Range of port numbers used to automatically bind.
3827    Need to determine whether we should perform a name_bind
3828    permission check between the socket and the port number. */
3829 
3830 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3831 {
3832 	struct sock *sk = sock->sk;
3833 	u16 family;
3834 	int err;
3835 
3836 	err = sock_has_perm(current, sk, SOCKET__BIND);
3837 	if (err)
3838 		goto out;
3839 
3840 	/*
3841 	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3842 	 * Multiple address binding for SCTP is not supported yet: we just
3843 	 * check the first address now.
3844 	 */
3845 	family = sk->sk_family;
3846 	if (family == PF_INET || family == PF_INET6) {
3847 		char *addrp;
3848 		struct sk_security_struct *sksec = sk->sk_security;
3849 		struct common_audit_data ad;
3850 		struct selinux_audit_data sad = {0,};
3851 		struct lsm_network_audit net = {0,};
3852 		struct sockaddr_in *addr4 = NULL;
3853 		struct sockaddr_in6 *addr6 = NULL;
3854 		unsigned short snum;
3855 		u32 sid, node_perm;
3856 
3857 		if (family == PF_INET) {
3858 			addr4 = (struct sockaddr_in *)address;
3859 			snum = ntohs(addr4->sin_port);
3860 			addrp = (char *)&addr4->sin_addr.s_addr;
3861 		} else {
3862 			addr6 = (struct sockaddr_in6 *)address;
3863 			snum = ntohs(addr6->sin6_port);
3864 			addrp = (char *)&addr6->sin6_addr.s6_addr;
3865 		}
3866 
3867 		if (snum) {
3868 			int low, high;
3869 
3870 			inet_get_local_port_range(&low, &high);
3871 
3872 			if (snum < max(PROT_SOCK, low) || snum > high) {
3873 				err = sel_netport_sid(sk->sk_protocol,
3874 						      snum, &sid);
3875 				if (err)
3876 					goto out;
3877 				COMMON_AUDIT_DATA_INIT(&ad, NET);
3878 				ad.selinux_audit_data = &sad;
3879 				ad.u.net = &net;
3880 				ad.u.net->sport = htons(snum);
3881 				ad.u.net->family = family;
3882 				err = avc_has_perm(sksec->sid, sid,
3883 						   sksec->sclass,
3884 						   SOCKET__NAME_BIND, &ad);
3885 				if (err)
3886 					goto out;
3887 			}
3888 		}
3889 
3890 		switch (sksec->sclass) {
3891 		case SECCLASS_TCP_SOCKET:
3892 			node_perm = TCP_SOCKET__NODE_BIND;
3893 			break;
3894 
3895 		case SECCLASS_UDP_SOCKET:
3896 			node_perm = UDP_SOCKET__NODE_BIND;
3897 			break;
3898 
3899 		case SECCLASS_DCCP_SOCKET:
3900 			node_perm = DCCP_SOCKET__NODE_BIND;
3901 			break;
3902 
3903 		default:
3904 			node_perm = RAWIP_SOCKET__NODE_BIND;
3905 			break;
3906 		}
3907 
3908 		err = sel_netnode_sid(addrp, family, &sid);
3909 		if (err)
3910 			goto out;
3911 
3912 		COMMON_AUDIT_DATA_INIT(&ad, NET);
3913 		ad.selinux_audit_data = &sad;
3914 		ad.u.net = &net;
3915 		ad.u.net->sport = htons(snum);
3916 		ad.u.net->family = family;
3917 
3918 		if (family == PF_INET)
3919 			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
3920 		else
3921 			ad.u.net->v6info.saddr = addr6->sin6_addr;
3922 
3923 		err = avc_has_perm(sksec->sid, sid,
3924 				   sksec->sclass, node_perm, &ad);
3925 		if (err)
3926 			goto out;
3927 	}
3928 out:
3929 	return err;
3930 }
3931 
3932 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3933 {
3934 	struct sock *sk = sock->sk;
3935 	struct sk_security_struct *sksec = sk->sk_security;
3936 	int err;
3937 
3938 	err = sock_has_perm(current, sk, SOCKET__CONNECT);
3939 	if (err)
3940 		return err;
3941 
3942 	/*
3943 	 * If a TCP or DCCP socket, check name_connect permission for the port.
3944 	 */
3945 	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3946 	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
3947 		struct common_audit_data ad;
3948 		struct selinux_audit_data sad = {0,};
3949 		struct lsm_network_audit net = {0,};
3950 		struct sockaddr_in *addr4 = NULL;
3951 		struct sockaddr_in6 *addr6 = NULL;
3952 		unsigned short snum;
3953 		u32 sid, perm;
3954 
3955 		if (sk->sk_family == PF_INET) {
3956 			addr4 = (struct sockaddr_in *)address;
3957 			if (addrlen < sizeof(struct sockaddr_in))
3958 				return -EINVAL;
3959 			snum = ntohs(addr4->sin_port);
3960 		} else {
3961 			addr6 = (struct sockaddr_in6 *)address;
3962 			if (addrlen < SIN6_LEN_RFC2133)
3963 				return -EINVAL;
3964 			snum = ntohs(addr6->sin6_port);
3965 		}
3966 
3967 		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3968 		if (err)
3969 			goto out;
3970 
3971 		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3972 		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3973 
3974 		COMMON_AUDIT_DATA_INIT(&ad, NET);
3975 		ad.selinux_audit_data = &sad;
3976 		ad.u.net = &net;
3977 		ad.u.net->dport = htons(snum);
3978 		ad.u.net->family = sk->sk_family;
3979 		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3980 		if (err)
3981 			goto out;
3982 	}
3983 
3984 	err = selinux_netlbl_socket_connect(sk, address);
3985 
3986 out:
3987 	return err;
3988 }
3989 
3990 static int selinux_socket_listen(struct socket *sock, int backlog)
3991 {
3992 	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3993 }
3994 
3995 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3996 {
3997 	int err;
3998 	struct inode_security_struct *isec;
3999 	struct inode_security_struct *newisec;
4000 
4001 	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4002 	if (err)
4003 		return err;
4004 
4005 	newisec = SOCK_INODE(newsock)->i_security;
4006 
4007 	isec = SOCK_INODE(sock)->i_security;
4008 	newisec->sclass = isec->sclass;
4009 	newisec->sid = isec->sid;
4010 	newisec->initialized = 1;
4011 
4012 	return 0;
4013 }
4014 
4015 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4016 				  int size)
4017 {
4018 	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4019 }
4020 
4021 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4022 				  int size, int flags)
4023 {
4024 	return sock_has_perm(current, sock->sk, SOCKET__READ);
4025 }
4026 
4027 static int selinux_socket_getsockname(struct socket *sock)
4028 {
4029 	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4030 }
4031 
4032 static int selinux_socket_getpeername(struct socket *sock)
4033 {
4034 	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4035 }
4036 
4037 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4038 {
4039 	int err;
4040 
4041 	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4042 	if (err)
4043 		return err;
4044 
4045 	return selinux_netlbl_socket_setsockopt(sock, level, optname);
4046 }
4047 
4048 static int selinux_socket_getsockopt(struct socket *sock, int level,
4049 				     int optname)
4050 {
4051 	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4052 }
4053 
4054 static int selinux_socket_shutdown(struct socket *sock, int how)
4055 {
4056 	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4057 }
4058 
4059 static int selinux_socket_unix_stream_connect(struct sock *sock,
4060 					      struct sock *other,
4061 					      struct sock *newsk)
4062 {
4063 	struct sk_security_struct *sksec_sock = sock->sk_security;
4064 	struct sk_security_struct *sksec_other = other->sk_security;
4065 	struct sk_security_struct *sksec_new = newsk->sk_security;
4066 	struct common_audit_data ad;
4067 	struct selinux_audit_data sad = {0,};
4068 	struct lsm_network_audit net = {0,};
4069 	int err;
4070 
4071 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4072 	ad.selinux_audit_data = &sad;
4073 	ad.u.net = &net;
4074 	ad.u.net->sk = other;
4075 
4076 	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4077 			   sksec_other->sclass,
4078 			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4079 	if (err)
4080 		return err;
4081 
4082 	/* server child socket */
4083 	sksec_new->peer_sid = sksec_sock->sid;
4084 	err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4085 				    &sksec_new->sid);
4086 	if (err)
4087 		return err;
4088 
4089 	/* connecting socket */
4090 	sksec_sock->peer_sid = sksec_new->sid;
4091 
4092 	return 0;
4093 }
4094 
4095 static int selinux_socket_unix_may_send(struct socket *sock,
4096 					struct socket *other)
4097 {
4098 	struct sk_security_struct *ssec = sock->sk->sk_security;
4099 	struct sk_security_struct *osec = other->sk->sk_security;
4100 	struct common_audit_data ad;
4101 	struct selinux_audit_data sad = {0,};
4102 	struct lsm_network_audit net = {0,};
4103 
4104 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4105 	ad.selinux_audit_data = &sad;
4106 	ad.u.net = &net;
4107 	ad.u.net->sk = other->sk;
4108 
4109 	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4110 			    &ad);
4111 }
4112 
4113 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4114 				    u32 peer_sid,
4115 				    struct common_audit_data *ad)
4116 {
4117 	int err;
4118 	u32 if_sid;
4119 	u32 node_sid;
4120 
4121 	err = sel_netif_sid(ifindex, &if_sid);
4122 	if (err)
4123 		return err;
4124 	err = avc_has_perm(peer_sid, if_sid,
4125 			   SECCLASS_NETIF, NETIF__INGRESS, ad);
4126 	if (err)
4127 		return err;
4128 
4129 	err = sel_netnode_sid(addrp, family, &node_sid);
4130 	if (err)
4131 		return err;
4132 	return avc_has_perm(peer_sid, node_sid,
4133 			    SECCLASS_NODE, NODE__RECVFROM, ad);
4134 }
4135 
4136 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4137 				       u16 family)
4138 {
4139 	int err = 0;
4140 	struct sk_security_struct *sksec = sk->sk_security;
4141 	u32 sk_sid = sksec->sid;
4142 	struct common_audit_data ad;
4143 	struct selinux_audit_data sad = {0,};
4144 	struct lsm_network_audit net = {0,};
4145 	char *addrp;
4146 
4147 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4148 	ad.selinux_audit_data = &sad;
4149 	ad.u.net = &net;
4150 	ad.u.net->netif = skb->skb_iif;
4151 	ad.u.net->family = family;
4152 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4153 	if (err)
4154 		return err;
4155 
4156 	if (selinux_secmark_enabled()) {
4157 		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4158 				   PACKET__RECV, &ad);
4159 		if (err)
4160 			return err;
4161 	}
4162 
4163 	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4164 	if (err)
4165 		return err;
4166 	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4167 
4168 	return err;
4169 }
4170 
4171 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4172 {
4173 	int err;
4174 	struct sk_security_struct *sksec = sk->sk_security;
4175 	u16 family = sk->sk_family;
4176 	u32 sk_sid = sksec->sid;
4177 	struct common_audit_data ad;
4178 	struct selinux_audit_data sad = {0,};
4179 	struct lsm_network_audit net = {0,};
4180 	char *addrp;
4181 	u8 secmark_active;
4182 	u8 peerlbl_active;
4183 
4184 	if (family != PF_INET && family != PF_INET6)
4185 		return 0;
4186 
4187 	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
4188 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4189 		family = PF_INET;
4190 
4191 	/* If any sort of compatibility mode is enabled then handoff processing
4192 	 * to the selinux_sock_rcv_skb_compat() function to deal with the
4193 	 * special handling.  We do this in an attempt to keep this function
4194 	 * as fast and as clean as possible. */
4195 	if (!selinux_policycap_netpeer)
4196 		return selinux_sock_rcv_skb_compat(sk, skb, family);
4197 
4198 	secmark_active = selinux_secmark_enabled();
4199 	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4200 	if (!secmark_active && !peerlbl_active)
4201 		return 0;
4202 
4203 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4204 	ad.selinux_audit_data = &sad;
4205 	ad.u.net = &net;
4206 	ad.u.net->netif = skb->skb_iif;
4207 	ad.u.net->family = family;
4208 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4209 	if (err)
4210 		return err;
4211 
4212 	if (peerlbl_active) {
4213 		u32 peer_sid;
4214 
4215 		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4216 		if (err)
4217 			return err;
4218 		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4219 					       peer_sid, &ad);
4220 		if (err) {
4221 			selinux_netlbl_err(skb, err, 0);
4222 			return err;
4223 		}
4224 		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4225 				   PEER__RECV, &ad);
4226 		if (err)
4227 			selinux_netlbl_err(skb, err, 0);
4228 	}
4229 
4230 	if (secmark_active) {
4231 		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4232 				   PACKET__RECV, &ad);
4233 		if (err)
4234 			return err;
4235 	}
4236 
4237 	return err;
4238 }
4239 
4240 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4241 					    int __user *optlen, unsigned len)
4242 {
4243 	int err = 0;
4244 	char *scontext;
4245 	u32 scontext_len;
4246 	struct sk_security_struct *sksec = sock->sk->sk_security;
4247 	u32 peer_sid = SECSID_NULL;
4248 
4249 	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4250 	    sksec->sclass == SECCLASS_TCP_SOCKET)
4251 		peer_sid = sksec->peer_sid;
4252 	if (peer_sid == SECSID_NULL)
4253 		return -ENOPROTOOPT;
4254 
4255 	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4256 	if (err)
4257 		return err;
4258 
4259 	if (scontext_len > len) {
4260 		err = -ERANGE;
4261 		goto out_len;
4262 	}
4263 
4264 	if (copy_to_user(optval, scontext, scontext_len))
4265 		err = -EFAULT;
4266 
4267 out_len:
4268 	if (put_user(scontext_len, optlen))
4269 		err = -EFAULT;
4270 	kfree(scontext);
4271 	return err;
4272 }
4273 
4274 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4275 {
4276 	u32 peer_secid = SECSID_NULL;
4277 	u16 family;
4278 
4279 	if (skb && skb->protocol == htons(ETH_P_IP))
4280 		family = PF_INET;
4281 	else if (skb && skb->protocol == htons(ETH_P_IPV6))
4282 		family = PF_INET6;
4283 	else if (sock)
4284 		family = sock->sk->sk_family;
4285 	else
4286 		goto out;
4287 
4288 	if (sock && family == PF_UNIX)
4289 		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4290 	else if (skb)
4291 		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4292 
4293 out:
4294 	*secid = peer_secid;
4295 	if (peer_secid == SECSID_NULL)
4296 		return -EINVAL;
4297 	return 0;
4298 }
4299 
4300 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4301 {
4302 	struct sk_security_struct *sksec;
4303 
4304 	sksec = kzalloc(sizeof(*sksec), priority);
4305 	if (!sksec)
4306 		return -ENOMEM;
4307 
4308 	sksec->peer_sid = SECINITSID_UNLABELED;
4309 	sksec->sid = SECINITSID_UNLABELED;
4310 	selinux_netlbl_sk_security_reset(sksec);
4311 	sk->sk_security = sksec;
4312 
4313 	return 0;
4314 }
4315 
4316 static void selinux_sk_free_security(struct sock *sk)
4317 {
4318 	struct sk_security_struct *sksec = sk->sk_security;
4319 
4320 	sk->sk_security = NULL;
4321 	selinux_netlbl_sk_security_free(sksec);
4322 	kfree(sksec);
4323 }
4324 
4325 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4326 {
4327 	struct sk_security_struct *sksec = sk->sk_security;
4328 	struct sk_security_struct *newsksec = newsk->sk_security;
4329 
4330 	newsksec->sid = sksec->sid;
4331 	newsksec->peer_sid = sksec->peer_sid;
4332 	newsksec->sclass = sksec->sclass;
4333 
4334 	selinux_netlbl_sk_security_reset(newsksec);
4335 }
4336 
4337 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4338 {
4339 	if (!sk)
4340 		*secid = SECINITSID_ANY_SOCKET;
4341 	else {
4342 		struct sk_security_struct *sksec = sk->sk_security;
4343 
4344 		*secid = sksec->sid;
4345 	}
4346 }
4347 
4348 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4349 {
4350 	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4351 	struct sk_security_struct *sksec = sk->sk_security;
4352 
4353 	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4354 	    sk->sk_family == PF_UNIX)
4355 		isec->sid = sksec->sid;
4356 	sksec->sclass = isec->sclass;
4357 }
4358 
4359 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4360 				     struct request_sock *req)
4361 {
4362 	struct sk_security_struct *sksec = sk->sk_security;
4363 	int err;
4364 	u16 family = sk->sk_family;
4365 	u32 newsid;
4366 	u32 peersid;
4367 
4368 	/* handle mapped IPv4 packets arriving via IPv6 sockets */
4369 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4370 		family = PF_INET;
4371 
4372 	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4373 	if (err)
4374 		return err;
4375 	if (peersid == SECSID_NULL) {
4376 		req->secid = sksec->sid;
4377 		req->peer_secid = SECSID_NULL;
4378 	} else {
4379 		err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4380 		if (err)
4381 			return err;
4382 		req->secid = newsid;
4383 		req->peer_secid = peersid;
4384 	}
4385 
4386 	return selinux_netlbl_inet_conn_request(req, family);
4387 }
4388 
4389 static void selinux_inet_csk_clone(struct sock *newsk,
4390 				   const struct request_sock *req)
4391 {
4392 	struct sk_security_struct *newsksec = newsk->sk_security;
4393 
4394 	newsksec->sid = req->secid;
4395 	newsksec->peer_sid = req->peer_secid;
4396 	/* NOTE: Ideally, we should also get the isec->sid for the
4397 	   new socket in sync, but we don't have the isec available yet.
4398 	   So we will wait until sock_graft to do it, by which
4399 	   time it will have been created and available. */
4400 
4401 	/* We don't need to take any sort of lock here as we are the only
4402 	 * thread with access to newsksec */
4403 	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4404 }
4405 
4406 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4407 {
4408 	u16 family = sk->sk_family;
4409 	struct sk_security_struct *sksec = sk->sk_security;
4410 
4411 	/* handle mapped IPv4 packets arriving via IPv6 sockets */
4412 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4413 		family = PF_INET;
4414 
4415 	selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4416 }
4417 
4418 static int selinux_secmark_relabel_packet(u32 sid)
4419 {
4420 	const struct task_security_struct *__tsec;
4421 	u32 tsid;
4422 
4423 	__tsec = current_security();
4424 	tsid = __tsec->sid;
4425 
4426 	return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4427 }
4428 
4429 static void selinux_secmark_refcount_inc(void)
4430 {
4431 	atomic_inc(&selinux_secmark_refcount);
4432 }
4433 
4434 static void selinux_secmark_refcount_dec(void)
4435 {
4436 	atomic_dec(&selinux_secmark_refcount);
4437 }
4438 
4439 static void selinux_req_classify_flow(const struct request_sock *req,
4440 				      struct flowi *fl)
4441 {
4442 	fl->flowi_secid = req->secid;
4443 }
4444 
4445 static int selinux_tun_dev_create(void)
4446 {
4447 	u32 sid = current_sid();
4448 
4449 	/* we aren't taking into account the "sockcreate" SID since the socket
4450 	 * that is being created here is not a socket in the traditional sense,
4451 	 * instead it is a private sock, accessible only to the kernel, and
4452 	 * representing a wide range of network traffic spanning multiple
4453 	 * connections unlike traditional sockets - check the TUN driver to
4454 	 * get a better understanding of why this socket is special */
4455 
4456 	return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4457 			    NULL);
4458 }
4459 
4460 static void selinux_tun_dev_post_create(struct sock *sk)
4461 {
4462 	struct sk_security_struct *sksec = sk->sk_security;
4463 
4464 	/* we don't currently perform any NetLabel based labeling here and it
4465 	 * isn't clear that we would want to do so anyway; while we could apply
4466 	 * labeling without the support of the TUN user the resulting labeled
4467 	 * traffic from the other end of the connection would almost certainly
4468 	 * cause confusion to the TUN user that had no idea network labeling
4469 	 * protocols were being used */
4470 
4471 	/* see the comments in selinux_tun_dev_create() about why we don't use
4472 	 * the sockcreate SID here */
4473 
4474 	sksec->sid = current_sid();
4475 	sksec->sclass = SECCLASS_TUN_SOCKET;
4476 }
4477 
4478 static int selinux_tun_dev_attach(struct sock *sk)
4479 {
4480 	struct sk_security_struct *sksec = sk->sk_security;
4481 	u32 sid = current_sid();
4482 	int err;
4483 
4484 	err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4485 			   TUN_SOCKET__RELABELFROM, NULL);
4486 	if (err)
4487 		return err;
4488 	err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4489 			   TUN_SOCKET__RELABELTO, NULL);
4490 	if (err)
4491 		return err;
4492 
4493 	sksec->sid = sid;
4494 
4495 	return 0;
4496 }
4497 
4498 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4499 {
4500 	int err = 0;
4501 	u32 perm;
4502 	struct nlmsghdr *nlh;
4503 	struct sk_security_struct *sksec = sk->sk_security;
4504 
4505 	if (skb->len < NLMSG_SPACE(0)) {
4506 		err = -EINVAL;
4507 		goto out;
4508 	}
4509 	nlh = nlmsg_hdr(skb);
4510 
4511 	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4512 	if (err) {
4513 		if (err == -EINVAL) {
4514 			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4515 				  "SELinux:  unrecognized netlink message"
4516 				  " type=%hu for sclass=%hu\n",
4517 				  nlh->nlmsg_type, sksec->sclass);
4518 			if (!selinux_enforcing || security_get_allow_unknown())
4519 				err = 0;
4520 		}
4521 
4522 		/* Ignore */
4523 		if (err == -ENOENT)
4524 			err = 0;
4525 		goto out;
4526 	}
4527 
4528 	err = sock_has_perm(current, sk, perm);
4529 out:
4530 	return err;
4531 }
4532 
4533 #ifdef CONFIG_NETFILTER
4534 
4535 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4536 				       u16 family)
4537 {
4538 	int err;
4539 	char *addrp;
4540 	u32 peer_sid;
4541 	struct common_audit_data ad;
4542 	struct selinux_audit_data sad = {0,};
4543 	struct lsm_network_audit net = {0,};
4544 	u8 secmark_active;
4545 	u8 netlbl_active;
4546 	u8 peerlbl_active;
4547 
4548 	if (!selinux_policycap_netpeer)
4549 		return NF_ACCEPT;
4550 
4551 	secmark_active = selinux_secmark_enabled();
4552 	netlbl_active = netlbl_enabled();
4553 	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4554 	if (!secmark_active && !peerlbl_active)
4555 		return NF_ACCEPT;
4556 
4557 	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4558 		return NF_DROP;
4559 
4560 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4561 	ad.selinux_audit_data = &sad;
4562 	ad.u.net = &net;
4563 	ad.u.net->netif = ifindex;
4564 	ad.u.net->family = family;
4565 	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4566 		return NF_DROP;
4567 
4568 	if (peerlbl_active) {
4569 		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4570 					       peer_sid, &ad);
4571 		if (err) {
4572 			selinux_netlbl_err(skb, err, 1);
4573 			return NF_DROP;
4574 		}
4575 	}
4576 
4577 	if (secmark_active)
4578 		if (avc_has_perm(peer_sid, skb->secmark,
4579 				 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4580 			return NF_DROP;
4581 
4582 	if (netlbl_active)
4583 		/* we do this in the FORWARD path and not the POST_ROUTING
4584 		 * path because we want to make sure we apply the necessary
4585 		 * labeling before IPsec is applied so we can leverage AH
4586 		 * protection */
4587 		if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4588 			return NF_DROP;
4589 
4590 	return NF_ACCEPT;
4591 }
4592 
4593 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4594 					 struct sk_buff *skb,
4595 					 const struct net_device *in,
4596 					 const struct net_device *out,
4597 					 int (*okfn)(struct sk_buff *))
4598 {
4599 	return selinux_ip_forward(skb, in->ifindex, PF_INET);
4600 }
4601 
4602 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4603 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4604 					 struct sk_buff *skb,
4605 					 const struct net_device *in,
4606 					 const struct net_device *out,
4607 					 int (*okfn)(struct sk_buff *))
4608 {
4609 	return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4610 }
4611 #endif	/* IPV6 */
4612 
4613 static unsigned int selinux_ip_output(struct sk_buff *skb,
4614 				      u16 family)
4615 {
4616 	u32 sid;
4617 
4618 	if (!netlbl_enabled())
4619 		return NF_ACCEPT;
4620 
4621 	/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4622 	 * because we want to make sure we apply the necessary labeling
4623 	 * before IPsec is applied so we can leverage AH protection */
4624 	if (skb->sk) {
4625 		struct sk_security_struct *sksec = skb->sk->sk_security;
4626 		sid = sksec->sid;
4627 	} else
4628 		sid = SECINITSID_KERNEL;
4629 	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4630 		return NF_DROP;
4631 
4632 	return NF_ACCEPT;
4633 }
4634 
4635 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4636 					struct sk_buff *skb,
4637 					const struct net_device *in,
4638 					const struct net_device *out,
4639 					int (*okfn)(struct sk_buff *))
4640 {
4641 	return selinux_ip_output(skb, PF_INET);
4642 }
4643 
4644 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4645 						int ifindex,
4646 						u16 family)
4647 {
4648 	struct sock *sk = skb->sk;
4649 	struct sk_security_struct *sksec;
4650 	struct common_audit_data ad;
4651 	struct selinux_audit_data sad = {0,};
4652 	struct lsm_network_audit net = {0,};
4653 	char *addrp;
4654 	u8 proto;
4655 
4656 	if (sk == NULL)
4657 		return NF_ACCEPT;
4658 	sksec = sk->sk_security;
4659 
4660 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4661 	ad.selinux_audit_data = &sad;
4662 	ad.u.net = &net;
4663 	ad.u.net->netif = ifindex;
4664 	ad.u.net->family = family;
4665 	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4666 		return NF_DROP;
4667 
4668 	if (selinux_secmark_enabled())
4669 		if (avc_has_perm(sksec->sid, skb->secmark,
4670 				 SECCLASS_PACKET, PACKET__SEND, &ad))
4671 			return NF_DROP_ERR(-ECONNREFUSED);
4672 
4673 	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4674 		return NF_DROP_ERR(-ECONNREFUSED);
4675 
4676 	return NF_ACCEPT;
4677 }
4678 
4679 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4680 					 u16 family)
4681 {
4682 	u32 secmark_perm;
4683 	u32 peer_sid;
4684 	struct sock *sk;
4685 	struct common_audit_data ad;
4686 	struct selinux_audit_data sad = {0,};
4687 	struct lsm_network_audit net = {0,};
4688 	char *addrp;
4689 	u8 secmark_active;
4690 	u8 peerlbl_active;
4691 
4692 	/* If any sort of compatibility mode is enabled then handoff processing
4693 	 * to the selinux_ip_postroute_compat() function to deal with the
4694 	 * special handling.  We do this in an attempt to keep this function
4695 	 * as fast and as clean as possible. */
4696 	if (!selinux_policycap_netpeer)
4697 		return selinux_ip_postroute_compat(skb, ifindex, family);
4698 #ifdef CONFIG_XFRM
4699 	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4700 	 * packet transformation so allow the packet to pass without any checks
4701 	 * since we'll have another chance to perform access control checks
4702 	 * when the packet is on it's final way out.
4703 	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4704 	 *       is NULL, in this case go ahead and apply access control. */
4705 	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4706 		return NF_ACCEPT;
4707 #endif
4708 	secmark_active = selinux_secmark_enabled();
4709 	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4710 	if (!secmark_active && !peerlbl_active)
4711 		return NF_ACCEPT;
4712 
4713 	/* if the packet is being forwarded then get the peer label from the
4714 	 * packet itself; otherwise check to see if it is from a local
4715 	 * application or the kernel, if from an application get the peer label
4716 	 * from the sending socket, otherwise use the kernel's sid */
4717 	sk = skb->sk;
4718 	if (sk == NULL) {
4719 		if (skb->skb_iif) {
4720 			secmark_perm = PACKET__FORWARD_OUT;
4721 			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4722 				return NF_DROP;
4723 		} else {
4724 			secmark_perm = PACKET__SEND;
4725 			peer_sid = SECINITSID_KERNEL;
4726 		}
4727 	} else {
4728 		struct sk_security_struct *sksec = sk->sk_security;
4729 		peer_sid = sksec->sid;
4730 		secmark_perm = PACKET__SEND;
4731 	}
4732 
4733 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4734 	ad.selinux_audit_data = &sad;
4735 	ad.u.net = &net;
4736 	ad.u.net->netif = ifindex;
4737 	ad.u.net->family = family;
4738 	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4739 		return NF_DROP;
4740 
4741 	if (secmark_active)
4742 		if (avc_has_perm(peer_sid, skb->secmark,
4743 				 SECCLASS_PACKET, secmark_perm, &ad))
4744 			return NF_DROP_ERR(-ECONNREFUSED);
4745 
4746 	if (peerlbl_active) {
4747 		u32 if_sid;
4748 		u32 node_sid;
4749 
4750 		if (sel_netif_sid(ifindex, &if_sid))
4751 			return NF_DROP;
4752 		if (avc_has_perm(peer_sid, if_sid,
4753 				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4754 			return NF_DROP_ERR(-ECONNREFUSED);
4755 
4756 		if (sel_netnode_sid(addrp, family, &node_sid))
4757 			return NF_DROP;
4758 		if (avc_has_perm(peer_sid, node_sid,
4759 				 SECCLASS_NODE, NODE__SENDTO, &ad))
4760 			return NF_DROP_ERR(-ECONNREFUSED);
4761 	}
4762 
4763 	return NF_ACCEPT;
4764 }
4765 
4766 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4767 					   struct sk_buff *skb,
4768 					   const struct net_device *in,
4769 					   const struct net_device *out,
4770 					   int (*okfn)(struct sk_buff *))
4771 {
4772 	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4773 }
4774 
4775 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4776 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4777 					   struct sk_buff *skb,
4778 					   const struct net_device *in,
4779 					   const struct net_device *out,
4780 					   int (*okfn)(struct sk_buff *))
4781 {
4782 	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4783 }
4784 #endif	/* IPV6 */
4785 
4786 #endif	/* CONFIG_NETFILTER */
4787 
4788 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4789 {
4790 	int err;
4791 
4792 	err = cap_netlink_send(sk, skb);
4793 	if (err)
4794 		return err;
4795 
4796 	return selinux_nlmsg_perm(sk, skb);
4797 }
4798 
4799 static int ipc_alloc_security(struct task_struct *task,
4800 			      struct kern_ipc_perm *perm,
4801 			      u16 sclass)
4802 {
4803 	struct ipc_security_struct *isec;
4804 	u32 sid;
4805 
4806 	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4807 	if (!isec)
4808 		return -ENOMEM;
4809 
4810 	sid = task_sid(task);
4811 	isec->sclass = sclass;
4812 	isec->sid = sid;
4813 	perm->security = isec;
4814 
4815 	return 0;
4816 }
4817 
4818 static void ipc_free_security(struct kern_ipc_perm *perm)
4819 {
4820 	struct ipc_security_struct *isec = perm->security;
4821 	perm->security = NULL;
4822 	kfree(isec);
4823 }
4824 
4825 static int msg_msg_alloc_security(struct msg_msg *msg)
4826 {
4827 	struct msg_security_struct *msec;
4828 
4829 	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4830 	if (!msec)
4831 		return -ENOMEM;
4832 
4833 	msec->sid = SECINITSID_UNLABELED;
4834 	msg->security = msec;
4835 
4836 	return 0;
4837 }
4838 
4839 static void msg_msg_free_security(struct msg_msg *msg)
4840 {
4841 	struct msg_security_struct *msec = msg->security;
4842 
4843 	msg->security = NULL;
4844 	kfree(msec);
4845 }
4846 
4847 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4848 			u32 perms)
4849 {
4850 	struct ipc_security_struct *isec;
4851 	struct common_audit_data ad;
4852 	struct selinux_audit_data sad = {0,};
4853 	u32 sid = current_sid();
4854 
4855 	isec = ipc_perms->security;
4856 
4857 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4858 	ad.selinux_audit_data = &sad;
4859 	ad.u.ipc_id = ipc_perms->key;
4860 
4861 	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4862 }
4863 
4864 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4865 {
4866 	return msg_msg_alloc_security(msg);
4867 }
4868 
4869 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4870 {
4871 	msg_msg_free_security(msg);
4872 }
4873 
4874 /* message queue security operations */
4875 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4876 {
4877 	struct ipc_security_struct *isec;
4878 	struct common_audit_data ad;
4879 	struct selinux_audit_data sad = {0,};
4880 	u32 sid = current_sid();
4881 	int rc;
4882 
4883 	rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4884 	if (rc)
4885 		return rc;
4886 
4887 	isec = msq->q_perm.security;
4888 
4889 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4890 	ad.selinux_audit_data = &sad;
4891 	ad.u.ipc_id = msq->q_perm.key;
4892 
4893 	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4894 			  MSGQ__CREATE, &ad);
4895 	if (rc) {
4896 		ipc_free_security(&msq->q_perm);
4897 		return rc;
4898 	}
4899 	return 0;
4900 }
4901 
4902 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4903 {
4904 	ipc_free_security(&msq->q_perm);
4905 }
4906 
4907 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4908 {
4909 	struct ipc_security_struct *isec;
4910 	struct common_audit_data ad;
4911 	struct selinux_audit_data sad = {0,};
4912 	u32 sid = current_sid();
4913 
4914 	isec = msq->q_perm.security;
4915 
4916 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4917 	ad.selinux_audit_data = &sad;
4918 	ad.u.ipc_id = msq->q_perm.key;
4919 
4920 	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4921 			    MSGQ__ASSOCIATE, &ad);
4922 }
4923 
4924 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4925 {
4926 	int err;
4927 	int perms;
4928 
4929 	switch (cmd) {
4930 	case IPC_INFO:
4931 	case MSG_INFO:
4932 		/* No specific object, just general system-wide information. */
4933 		return task_has_system(current, SYSTEM__IPC_INFO);
4934 	case IPC_STAT:
4935 	case MSG_STAT:
4936 		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4937 		break;
4938 	case IPC_SET:
4939 		perms = MSGQ__SETATTR;
4940 		break;
4941 	case IPC_RMID:
4942 		perms = MSGQ__DESTROY;
4943 		break;
4944 	default:
4945 		return 0;
4946 	}
4947 
4948 	err = ipc_has_perm(&msq->q_perm, perms);
4949 	return err;
4950 }
4951 
4952 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4953 {
4954 	struct ipc_security_struct *isec;
4955 	struct msg_security_struct *msec;
4956 	struct common_audit_data ad;
4957 	struct selinux_audit_data sad = {0,};
4958 	u32 sid = current_sid();
4959 	int rc;
4960 
4961 	isec = msq->q_perm.security;
4962 	msec = msg->security;
4963 
4964 	/*
4965 	 * First time through, need to assign label to the message
4966 	 */
4967 	if (msec->sid == SECINITSID_UNLABELED) {
4968 		/*
4969 		 * Compute new sid based on current process and
4970 		 * message queue this message will be stored in
4971 		 */
4972 		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4973 					     NULL, &msec->sid);
4974 		if (rc)
4975 			return rc;
4976 	}
4977 
4978 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4979 	ad.selinux_audit_data = &sad;
4980 	ad.u.ipc_id = msq->q_perm.key;
4981 
4982 	/* Can this process write to the queue? */
4983 	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4984 			  MSGQ__WRITE, &ad);
4985 	if (!rc)
4986 		/* Can this process send the message */
4987 		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4988 				  MSG__SEND, &ad);
4989 	if (!rc)
4990 		/* Can the message be put in the queue? */
4991 		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4992 				  MSGQ__ENQUEUE, &ad);
4993 
4994 	return rc;
4995 }
4996 
4997 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4998 				    struct task_struct *target,
4999 				    long type, int mode)
5000 {
5001 	struct ipc_security_struct *isec;
5002 	struct msg_security_struct *msec;
5003 	struct common_audit_data ad;
5004 	struct selinux_audit_data sad = {0,};
5005 	u32 sid = task_sid(target);
5006 	int rc;
5007 
5008 	isec = msq->q_perm.security;
5009 	msec = msg->security;
5010 
5011 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5012 	ad.selinux_audit_data = &sad;
5013 	ad.u.ipc_id = msq->q_perm.key;
5014 
5015 	rc = avc_has_perm(sid, isec->sid,
5016 			  SECCLASS_MSGQ, MSGQ__READ, &ad);
5017 	if (!rc)
5018 		rc = avc_has_perm(sid, msec->sid,
5019 				  SECCLASS_MSG, MSG__RECEIVE, &ad);
5020 	return rc;
5021 }
5022 
5023 /* Shared Memory security operations */
5024 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5025 {
5026 	struct ipc_security_struct *isec;
5027 	struct common_audit_data ad;
5028 	struct selinux_audit_data sad = {0,};
5029 	u32 sid = current_sid();
5030 	int rc;
5031 
5032 	rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5033 	if (rc)
5034 		return rc;
5035 
5036 	isec = shp->shm_perm.security;
5037 
5038 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5039 	ad.selinux_audit_data = &sad;
5040 	ad.u.ipc_id = shp->shm_perm.key;
5041 
5042 	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5043 			  SHM__CREATE, &ad);
5044 	if (rc) {
5045 		ipc_free_security(&shp->shm_perm);
5046 		return rc;
5047 	}
5048 	return 0;
5049 }
5050 
5051 static void selinux_shm_free_security(struct shmid_kernel *shp)
5052 {
5053 	ipc_free_security(&shp->shm_perm);
5054 }
5055 
5056 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5057 {
5058 	struct ipc_security_struct *isec;
5059 	struct common_audit_data ad;
5060 	struct selinux_audit_data sad = {0,};
5061 	u32 sid = current_sid();
5062 
5063 	isec = shp->shm_perm.security;
5064 
5065 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5066 	ad.selinux_audit_data = &sad;
5067 	ad.u.ipc_id = shp->shm_perm.key;
5068 
5069 	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5070 			    SHM__ASSOCIATE, &ad);
5071 }
5072 
5073 /* Note, at this point, shp is locked down */
5074 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5075 {
5076 	int perms;
5077 	int err;
5078 
5079 	switch (cmd) {
5080 	case IPC_INFO:
5081 	case SHM_INFO:
5082 		/* No specific object, just general system-wide information. */
5083 		return task_has_system(current, SYSTEM__IPC_INFO);
5084 	case IPC_STAT:
5085 	case SHM_STAT:
5086 		perms = SHM__GETATTR | SHM__ASSOCIATE;
5087 		break;
5088 	case IPC_SET:
5089 		perms = SHM__SETATTR;
5090 		break;
5091 	case SHM_LOCK:
5092 	case SHM_UNLOCK:
5093 		perms = SHM__LOCK;
5094 		break;
5095 	case IPC_RMID:
5096 		perms = SHM__DESTROY;
5097 		break;
5098 	default:
5099 		return 0;
5100 	}
5101 
5102 	err = ipc_has_perm(&shp->shm_perm, perms);
5103 	return err;
5104 }
5105 
5106 static int selinux_shm_shmat(struct shmid_kernel *shp,
5107 			     char __user *shmaddr, int shmflg)
5108 {
5109 	u32 perms;
5110 
5111 	if (shmflg & SHM_RDONLY)
5112 		perms = SHM__READ;
5113 	else
5114 		perms = SHM__READ | SHM__WRITE;
5115 
5116 	return ipc_has_perm(&shp->shm_perm, perms);
5117 }
5118 
5119 /* Semaphore security operations */
5120 static int selinux_sem_alloc_security(struct sem_array *sma)
5121 {
5122 	struct ipc_security_struct *isec;
5123 	struct common_audit_data ad;
5124 	struct selinux_audit_data sad = {0,};
5125 	u32 sid = current_sid();
5126 	int rc;
5127 
5128 	rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5129 	if (rc)
5130 		return rc;
5131 
5132 	isec = sma->sem_perm.security;
5133 
5134 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5135 	ad.selinux_audit_data = &sad;
5136 	ad.u.ipc_id = sma->sem_perm.key;
5137 
5138 	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5139 			  SEM__CREATE, &ad);
5140 	if (rc) {
5141 		ipc_free_security(&sma->sem_perm);
5142 		return rc;
5143 	}
5144 	return 0;
5145 }
5146 
5147 static void selinux_sem_free_security(struct sem_array *sma)
5148 {
5149 	ipc_free_security(&sma->sem_perm);
5150 }
5151 
5152 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5153 {
5154 	struct ipc_security_struct *isec;
5155 	struct common_audit_data ad;
5156 	struct selinux_audit_data sad = {0,};
5157 	u32 sid = current_sid();
5158 
5159 	isec = sma->sem_perm.security;
5160 
5161 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5162 	ad.selinux_audit_data = &sad;
5163 	ad.u.ipc_id = sma->sem_perm.key;
5164 
5165 	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5166 			    SEM__ASSOCIATE, &ad);
5167 }
5168 
5169 /* Note, at this point, sma is locked down */
5170 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5171 {
5172 	int err;
5173 	u32 perms;
5174 
5175 	switch (cmd) {
5176 	case IPC_INFO:
5177 	case SEM_INFO:
5178 		/* No specific object, just general system-wide information. */
5179 		return task_has_system(current, SYSTEM__IPC_INFO);
5180 	case GETPID:
5181 	case GETNCNT:
5182 	case GETZCNT:
5183 		perms = SEM__GETATTR;
5184 		break;
5185 	case GETVAL:
5186 	case GETALL:
5187 		perms = SEM__READ;
5188 		break;
5189 	case SETVAL:
5190 	case SETALL:
5191 		perms = SEM__WRITE;
5192 		break;
5193 	case IPC_RMID:
5194 		perms = SEM__DESTROY;
5195 		break;
5196 	case IPC_SET:
5197 		perms = SEM__SETATTR;
5198 		break;
5199 	case IPC_STAT:
5200 	case SEM_STAT:
5201 		perms = SEM__GETATTR | SEM__ASSOCIATE;
5202 		break;
5203 	default:
5204 		return 0;
5205 	}
5206 
5207 	err = ipc_has_perm(&sma->sem_perm, perms);
5208 	return err;
5209 }
5210 
5211 static int selinux_sem_semop(struct sem_array *sma,
5212 			     struct sembuf *sops, unsigned nsops, int alter)
5213 {
5214 	u32 perms;
5215 
5216 	if (alter)
5217 		perms = SEM__READ | SEM__WRITE;
5218 	else
5219 		perms = SEM__READ;
5220 
5221 	return ipc_has_perm(&sma->sem_perm, perms);
5222 }
5223 
5224 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5225 {
5226 	u32 av = 0;
5227 
5228 	av = 0;
5229 	if (flag & S_IRUGO)
5230 		av |= IPC__UNIX_READ;
5231 	if (flag & S_IWUGO)
5232 		av |= IPC__UNIX_WRITE;
5233 
5234 	if (av == 0)
5235 		return 0;
5236 
5237 	return ipc_has_perm(ipcp, av);
5238 }
5239 
5240 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5241 {
5242 	struct ipc_security_struct *isec = ipcp->security;
5243 	*secid = isec->sid;
5244 }
5245 
5246 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5247 {
5248 	if (inode)
5249 		inode_doinit_with_dentry(inode, dentry);
5250 }
5251 
5252 static int selinux_getprocattr(struct task_struct *p,
5253 			       char *name, char **value)
5254 {
5255 	const struct task_security_struct *__tsec;
5256 	u32 sid;
5257 	int error;
5258 	unsigned len;
5259 
5260 	if (current != p) {
5261 		error = current_has_perm(p, PROCESS__GETATTR);
5262 		if (error)
5263 			return error;
5264 	}
5265 
5266 	rcu_read_lock();
5267 	__tsec = __task_cred(p)->security;
5268 
5269 	if (!strcmp(name, "current"))
5270 		sid = __tsec->sid;
5271 	else if (!strcmp(name, "prev"))
5272 		sid = __tsec->osid;
5273 	else if (!strcmp(name, "exec"))
5274 		sid = __tsec->exec_sid;
5275 	else if (!strcmp(name, "fscreate"))
5276 		sid = __tsec->create_sid;
5277 	else if (!strcmp(name, "keycreate"))
5278 		sid = __tsec->keycreate_sid;
5279 	else if (!strcmp(name, "sockcreate"))
5280 		sid = __tsec->sockcreate_sid;
5281 	else
5282 		goto invalid;
5283 	rcu_read_unlock();
5284 
5285 	if (!sid)
5286 		return 0;
5287 
5288 	error = security_sid_to_context(sid, value, &len);
5289 	if (error)
5290 		return error;
5291 	return len;
5292 
5293 invalid:
5294 	rcu_read_unlock();
5295 	return -EINVAL;
5296 }
5297 
5298 static int selinux_setprocattr(struct task_struct *p,
5299 			       char *name, void *value, size_t size)
5300 {
5301 	struct task_security_struct *tsec;
5302 	struct task_struct *tracer;
5303 	struct cred *new;
5304 	u32 sid = 0, ptsid;
5305 	int error;
5306 	char *str = value;
5307 
5308 	if (current != p) {
5309 		/* SELinux only allows a process to change its own
5310 		   security attributes. */
5311 		return -EACCES;
5312 	}
5313 
5314 	/*
5315 	 * Basic control over ability to set these attributes at all.
5316 	 * current == p, but we'll pass them separately in case the
5317 	 * above restriction is ever removed.
5318 	 */
5319 	if (!strcmp(name, "exec"))
5320 		error = current_has_perm(p, PROCESS__SETEXEC);
5321 	else if (!strcmp(name, "fscreate"))
5322 		error = current_has_perm(p, PROCESS__SETFSCREATE);
5323 	else if (!strcmp(name, "keycreate"))
5324 		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5325 	else if (!strcmp(name, "sockcreate"))
5326 		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5327 	else if (!strcmp(name, "current"))
5328 		error = current_has_perm(p, PROCESS__SETCURRENT);
5329 	else
5330 		error = -EINVAL;
5331 	if (error)
5332 		return error;
5333 
5334 	/* Obtain a SID for the context, if one was specified. */
5335 	if (size && str[1] && str[1] != '\n') {
5336 		if (str[size-1] == '\n') {
5337 			str[size-1] = 0;
5338 			size--;
5339 		}
5340 		error = security_context_to_sid(value, size, &sid);
5341 		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5342 			if (!capable(CAP_MAC_ADMIN))
5343 				return error;
5344 			error = security_context_to_sid_force(value, size,
5345 							      &sid);
5346 		}
5347 		if (error)
5348 			return error;
5349 	}
5350 
5351 	new = prepare_creds();
5352 	if (!new)
5353 		return -ENOMEM;
5354 
5355 	/* Permission checking based on the specified context is
5356 	   performed during the actual operation (execve,
5357 	   open/mkdir/...), when we know the full context of the
5358 	   operation.  See selinux_bprm_set_creds for the execve
5359 	   checks and may_create for the file creation checks. The
5360 	   operation will then fail if the context is not permitted. */
5361 	tsec = new->security;
5362 	if (!strcmp(name, "exec")) {
5363 		tsec->exec_sid = sid;
5364 	} else if (!strcmp(name, "fscreate")) {
5365 		tsec->create_sid = sid;
5366 	} else if (!strcmp(name, "keycreate")) {
5367 		error = may_create_key(sid, p);
5368 		if (error)
5369 			goto abort_change;
5370 		tsec->keycreate_sid = sid;
5371 	} else if (!strcmp(name, "sockcreate")) {
5372 		tsec->sockcreate_sid = sid;
5373 	} else if (!strcmp(name, "current")) {
5374 		error = -EINVAL;
5375 		if (sid == 0)
5376 			goto abort_change;
5377 
5378 		/* Only allow single threaded processes to change context */
5379 		error = -EPERM;
5380 		if (!current_is_single_threaded()) {
5381 			error = security_bounded_transition(tsec->sid, sid);
5382 			if (error)
5383 				goto abort_change;
5384 		}
5385 
5386 		/* Check permissions for the transition. */
5387 		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5388 				     PROCESS__DYNTRANSITION, NULL);
5389 		if (error)
5390 			goto abort_change;
5391 
5392 		/* Check for ptracing, and update the task SID if ok.
5393 		   Otherwise, leave SID unchanged and fail. */
5394 		ptsid = 0;
5395 		task_lock(p);
5396 		tracer = ptrace_parent(p);
5397 		if (tracer)
5398 			ptsid = task_sid(tracer);
5399 		task_unlock(p);
5400 
5401 		if (tracer) {
5402 			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5403 					     PROCESS__PTRACE, NULL);
5404 			if (error)
5405 				goto abort_change;
5406 		}
5407 
5408 		tsec->sid = sid;
5409 	} else {
5410 		error = -EINVAL;
5411 		goto abort_change;
5412 	}
5413 
5414 	commit_creds(new);
5415 	return size;
5416 
5417 abort_change:
5418 	abort_creds(new);
5419 	return error;
5420 }
5421 
5422 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5423 {
5424 	return security_sid_to_context(secid, secdata, seclen);
5425 }
5426 
5427 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5428 {
5429 	return security_context_to_sid(secdata, seclen, secid);
5430 }
5431 
5432 static void selinux_release_secctx(char *secdata, u32 seclen)
5433 {
5434 	kfree(secdata);
5435 }
5436 
5437 /*
5438  *	called with inode->i_mutex locked
5439  */
5440 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5441 {
5442 	return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5443 }
5444 
5445 /*
5446  *	called with inode->i_mutex locked
5447  */
5448 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5449 {
5450 	return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5451 }
5452 
5453 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5454 {
5455 	int len = 0;
5456 	len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5457 						ctx, true);
5458 	if (len < 0)
5459 		return len;
5460 	*ctxlen = len;
5461 	return 0;
5462 }
5463 #ifdef CONFIG_KEYS
5464 
5465 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5466 			     unsigned long flags)
5467 {
5468 	const struct task_security_struct *tsec;
5469 	struct key_security_struct *ksec;
5470 
5471 	ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5472 	if (!ksec)
5473 		return -ENOMEM;
5474 
5475 	tsec = cred->security;
5476 	if (tsec->keycreate_sid)
5477 		ksec->sid = tsec->keycreate_sid;
5478 	else
5479 		ksec->sid = tsec->sid;
5480 
5481 	k->security = ksec;
5482 	return 0;
5483 }
5484 
5485 static void selinux_key_free(struct key *k)
5486 {
5487 	struct key_security_struct *ksec = k->security;
5488 
5489 	k->security = NULL;
5490 	kfree(ksec);
5491 }
5492 
5493 static int selinux_key_permission(key_ref_t key_ref,
5494 				  const struct cred *cred,
5495 				  key_perm_t perm)
5496 {
5497 	struct key *key;
5498 	struct key_security_struct *ksec;
5499 	u32 sid;
5500 
5501 	/* if no specific permissions are requested, we skip the
5502 	   permission check. No serious, additional covert channels
5503 	   appear to be created. */
5504 	if (perm == 0)
5505 		return 0;
5506 
5507 	sid = cred_sid(cred);
5508 
5509 	key = key_ref_to_ptr(key_ref);
5510 	ksec = key->security;
5511 
5512 	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5513 }
5514 
5515 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5516 {
5517 	struct key_security_struct *ksec = key->security;
5518 	char *context = NULL;
5519 	unsigned len;
5520 	int rc;
5521 
5522 	rc = security_sid_to_context(ksec->sid, &context, &len);
5523 	if (!rc)
5524 		rc = len;
5525 	*_buffer = context;
5526 	return rc;
5527 }
5528 
5529 #endif
5530 
5531 static struct security_operations selinux_ops = {
5532 	.name =				"selinux",
5533 
5534 	.ptrace_access_check =		selinux_ptrace_access_check,
5535 	.ptrace_traceme =		selinux_ptrace_traceme,
5536 	.capget =			selinux_capget,
5537 	.capset =			selinux_capset,
5538 	.capable =			selinux_capable,
5539 	.quotactl =			selinux_quotactl,
5540 	.quota_on =			selinux_quota_on,
5541 	.syslog =			selinux_syslog,
5542 	.vm_enough_memory =		selinux_vm_enough_memory,
5543 
5544 	.netlink_send =			selinux_netlink_send,
5545 
5546 	.bprm_set_creds =		selinux_bprm_set_creds,
5547 	.bprm_committing_creds =	selinux_bprm_committing_creds,
5548 	.bprm_committed_creds =		selinux_bprm_committed_creds,
5549 	.bprm_secureexec =		selinux_bprm_secureexec,
5550 
5551 	.sb_alloc_security =		selinux_sb_alloc_security,
5552 	.sb_free_security =		selinux_sb_free_security,
5553 	.sb_copy_data =			selinux_sb_copy_data,
5554 	.sb_remount =			selinux_sb_remount,
5555 	.sb_kern_mount =		selinux_sb_kern_mount,
5556 	.sb_show_options =		selinux_sb_show_options,
5557 	.sb_statfs =			selinux_sb_statfs,
5558 	.sb_mount =			selinux_mount,
5559 	.sb_umount =			selinux_umount,
5560 	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5561 	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5562 	.sb_parse_opts_str = 		selinux_parse_opts_str,
5563 
5564 
5565 	.inode_alloc_security =		selinux_inode_alloc_security,
5566 	.inode_free_security =		selinux_inode_free_security,
5567 	.inode_init_security =		selinux_inode_init_security,
5568 	.inode_create =			selinux_inode_create,
5569 	.inode_link =			selinux_inode_link,
5570 	.inode_unlink =			selinux_inode_unlink,
5571 	.inode_symlink =		selinux_inode_symlink,
5572 	.inode_mkdir =			selinux_inode_mkdir,
5573 	.inode_rmdir =			selinux_inode_rmdir,
5574 	.inode_mknod =			selinux_inode_mknod,
5575 	.inode_rename =			selinux_inode_rename,
5576 	.inode_readlink =		selinux_inode_readlink,
5577 	.inode_follow_link =		selinux_inode_follow_link,
5578 	.inode_permission =		selinux_inode_permission,
5579 	.inode_setattr =		selinux_inode_setattr,
5580 	.inode_getattr =		selinux_inode_getattr,
5581 	.inode_setxattr =		selinux_inode_setxattr,
5582 	.inode_post_setxattr =		selinux_inode_post_setxattr,
5583 	.inode_getxattr =		selinux_inode_getxattr,
5584 	.inode_listxattr =		selinux_inode_listxattr,
5585 	.inode_removexattr =		selinux_inode_removexattr,
5586 	.inode_getsecurity =		selinux_inode_getsecurity,
5587 	.inode_setsecurity =		selinux_inode_setsecurity,
5588 	.inode_listsecurity =		selinux_inode_listsecurity,
5589 	.inode_getsecid =		selinux_inode_getsecid,
5590 
5591 	.file_permission =		selinux_file_permission,
5592 	.file_alloc_security =		selinux_file_alloc_security,
5593 	.file_free_security =		selinux_file_free_security,
5594 	.file_ioctl =			selinux_file_ioctl,
5595 	.file_mmap =			selinux_file_mmap,
5596 	.file_mprotect =		selinux_file_mprotect,
5597 	.file_lock =			selinux_file_lock,
5598 	.file_fcntl =			selinux_file_fcntl,
5599 	.file_set_fowner =		selinux_file_set_fowner,
5600 	.file_send_sigiotask =		selinux_file_send_sigiotask,
5601 	.file_receive =			selinux_file_receive,
5602 
5603 	.dentry_open =			selinux_dentry_open,
5604 
5605 	.task_create =			selinux_task_create,
5606 	.cred_alloc_blank =		selinux_cred_alloc_blank,
5607 	.cred_free =			selinux_cred_free,
5608 	.cred_prepare =			selinux_cred_prepare,
5609 	.cred_transfer =		selinux_cred_transfer,
5610 	.kernel_act_as =		selinux_kernel_act_as,
5611 	.kernel_create_files_as =	selinux_kernel_create_files_as,
5612 	.kernel_module_request =	selinux_kernel_module_request,
5613 	.task_setpgid =			selinux_task_setpgid,
5614 	.task_getpgid =			selinux_task_getpgid,
5615 	.task_getsid =			selinux_task_getsid,
5616 	.task_getsecid =		selinux_task_getsecid,
5617 	.task_setnice =			selinux_task_setnice,
5618 	.task_setioprio =		selinux_task_setioprio,
5619 	.task_getioprio =		selinux_task_getioprio,
5620 	.task_setrlimit =		selinux_task_setrlimit,
5621 	.task_setscheduler =		selinux_task_setscheduler,
5622 	.task_getscheduler =		selinux_task_getscheduler,
5623 	.task_movememory =		selinux_task_movememory,
5624 	.task_kill =			selinux_task_kill,
5625 	.task_wait =			selinux_task_wait,
5626 	.task_to_inode =		selinux_task_to_inode,
5627 
5628 	.ipc_permission =		selinux_ipc_permission,
5629 	.ipc_getsecid =			selinux_ipc_getsecid,
5630 
5631 	.msg_msg_alloc_security =	selinux_msg_msg_alloc_security,
5632 	.msg_msg_free_security =	selinux_msg_msg_free_security,
5633 
5634 	.msg_queue_alloc_security =	selinux_msg_queue_alloc_security,
5635 	.msg_queue_free_security =	selinux_msg_queue_free_security,
5636 	.msg_queue_associate =		selinux_msg_queue_associate,
5637 	.msg_queue_msgctl =		selinux_msg_queue_msgctl,
5638 	.msg_queue_msgsnd =		selinux_msg_queue_msgsnd,
5639 	.msg_queue_msgrcv =		selinux_msg_queue_msgrcv,
5640 
5641 	.shm_alloc_security =		selinux_shm_alloc_security,
5642 	.shm_free_security =		selinux_shm_free_security,
5643 	.shm_associate =		selinux_shm_associate,
5644 	.shm_shmctl =			selinux_shm_shmctl,
5645 	.shm_shmat =			selinux_shm_shmat,
5646 
5647 	.sem_alloc_security =		selinux_sem_alloc_security,
5648 	.sem_free_security =		selinux_sem_free_security,
5649 	.sem_associate =		selinux_sem_associate,
5650 	.sem_semctl =			selinux_sem_semctl,
5651 	.sem_semop =			selinux_sem_semop,
5652 
5653 	.d_instantiate =		selinux_d_instantiate,
5654 
5655 	.getprocattr =			selinux_getprocattr,
5656 	.setprocattr =			selinux_setprocattr,
5657 
5658 	.secid_to_secctx =		selinux_secid_to_secctx,
5659 	.secctx_to_secid =		selinux_secctx_to_secid,
5660 	.release_secctx =		selinux_release_secctx,
5661 	.inode_notifysecctx =		selinux_inode_notifysecctx,
5662 	.inode_setsecctx =		selinux_inode_setsecctx,
5663 	.inode_getsecctx =		selinux_inode_getsecctx,
5664 
5665 	.unix_stream_connect =		selinux_socket_unix_stream_connect,
5666 	.unix_may_send =		selinux_socket_unix_may_send,
5667 
5668 	.socket_create =		selinux_socket_create,
5669 	.socket_post_create =		selinux_socket_post_create,
5670 	.socket_bind =			selinux_socket_bind,
5671 	.socket_connect =		selinux_socket_connect,
5672 	.socket_listen =		selinux_socket_listen,
5673 	.socket_accept =		selinux_socket_accept,
5674 	.socket_sendmsg =		selinux_socket_sendmsg,
5675 	.socket_recvmsg =		selinux_socket_recvmsg,
5676 	.socket_getsockname =		selinux_socket_getsockname,
5677 	.socket_getpeername =		selinux_socket_getpeername,
5678 	.socket_getsockopt =		selinux_socket_getsockopt,
5679 	.socket_setsockopt =		selinux_socket_setsockopt,
5680 	.socket_shutdown =		selinux_socket_shutdown,
5681 	.socket_sock_rcv_skb =		selinux_socket_sock_rcv_skb,
5682 	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
5683 	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
5684 	.sk_alloc_security =		selinux_sk_alloc_security,
5685 	.sk_free_security =		selinux_sk_free_security,
5686 	.sk_clone_security =		selinux_sk_clone_security,
5687 	.sk_getsecid =			selinux_sk_getsecid,
5688 	.sock_graft =			selinux_sock_graft,
5689 	.inet_conn_request =		selinux_inet_conn_request,
5690 	.inet_csk_clone =		selinux_inet_csk_clone,
5691 	.inet_conn_established =	selinux_inet_conn_established,
5692 	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
5693 	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
5694 	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5695 	.req_classify_flow =		selinux_req_classify_flow,
5696 	.tun_dev_create =		selinux_tun_dev_create,
5697 	.tun_dev_post_create = 		selinux_tun_dev_post_create,
5698 	.tun_dev_attach =		selinux_tun_dev_attach,
5699 
5700 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5701 	.xfrm_policy_alloc_security =	selinux_xfrm_policy_alloc,
5702 	.xfrm_policy_clone_security =	selinux_xfrm_policy_clone,
5703 	.xfrm_policy_free_security =	selinux_xfrm_policy_free,
5704 	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5705 	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
5706 	.xfrm_state_free_security =	selinux_xfrm_state_free,
5707 	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5708 	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5709 	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
5710 	.xfrm_decode_session =		selinux_xfrm_decode_session,
5711 #endif
5712 
5713 #ifdef CONFIG_KEYS
5714 	.key_alloc =			selinux_key_alloc,
5715 	.key_free =			selinux_key_free,
5716 	.key_permission =		selinux_key_permission,
5717 	.key_getsecurity =		selinux_key_getsecurity,
5718 #endif
5719 
5720 #ifdef CONFIG_AUDIT
5721 	.audit_rule_init =		selinux_audit_rule_init,
5722 	.audit_rule_known =		selinux_audit_rule_known,
5723 	.audit_rule_match =		selinux_audit_rule_match,
5724 	.audit_rule_free =		selinux_audit_rule_free,
5725 #endif
5726 };
5727 
5728 static __init int selinux_init(void)
5729 {
5730 	if (!security_module_enable(&selinux_ops)) {
5731 		selinux_enabled = 0;
5732 		return 0;
5733 	}
5734 
5735 	if (!selinux_enabled) {
5736 		printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5737 		return 0;
5738 	}
5739 
5740 	printk(KERN_INFO "SELinux:  Initializing.\n");
5741 
5742 	/* Set the security state for the initial task. */
5743 	cred_init_security();
5744 
5745 	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5746 
5747 	sel_inode_cache = kmem_cache_create("selinux_inode_security",
5748 					    sizeof(struct inode_security_struct),
5749 					    0, SLAB_PANIC, NULL);
5750 	avc_init();
5751 
5752 	if (register_security(&selinux_ops))
5753 		panic("SELinux: Unable to register with kernel.\n");
5754 
5755 	if (selinux_enforcing)
5756 		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5757 	else
5758 		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5759 
5760 	return 0;
5761 }
5762 
5763 static void delayed_superblock_init(struct super_block *sb, void *unused)
5764 {
5765 	superblock_doinit(sb, NULL);
5766 }
5767 
5768 void selinux_complete_init(void)
5769 {
5770 	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5771 
5772 	/* Set up any superblocks initialized prior to the policy load. */
5773 	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5774 	iterate_supers(delayed_superblock_init, NULL);
5775 }
5776 
5777 /* SELinux requires early initialization in order to label
5778    all processes and objects when they are created. */
5779 security_initcall(selinux_init);
5780 
5781 #if defined(CONFIG_NETFILTER)
5782 
5783 static struct nf_hook_ops selinux_ipv4_ops[] = {
5784 	{
5785 		.hook =		selinux_ipv4_postroute,
5786 		.owner =	THIS_MODULE,
5787 		.pf =		PF_INET,
5788 		.hooknum =	NF_INET_POST_ROUTING,
5789 		.priority =	NF_IP_PRI_SELINUX_LAST,
5790 	},
5791 	{
5792 		.hook =		selinux_ipv4_forward,
5793 		.owner =	THIS_MODULE,
5794 		.pf =		PF_INET,
5795 		.hooknum =	NF_INET_FORWARD,
5796 		.priority =	NF_IP_PRI_SELINUX_FIRST,
5797 	},
5798 	{
5799 		.hook =		selinux_ipv4_output,
5800 		.owner =	THIS_MODULE,
5801 		.pf =		PF_INET,
5802 		.hooknum =	NF_INET_LOCAL_OUT,
5803 		.priority =	NF_IP_PRI_SELINUX_FIRST,
5804 	}
5805 };
5806 
5807 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5808 
5809 static struct nf_hook_ops selinux_ipv6_ops[] = {
5810 	{
5811 		.hook =		selinux_ipv6_postroute,
5812 		.owner =	THIS_MODULE,
5813 		.pf =		PF_INET6,
5814 		.hooknum =	NF_INET_POST_ROUTING,
5815 		.priority =	NF_IP6_PRI_SELINUX_LAST,
5816 	},
5817 	{
5818 		.hook =		selinux_ipv6_forward,
5819 		.owner =	THIS_MODULE,
5820 		.pf =		PF_INET6,
5821 		.hooknum =	NF_INET_FORWARD,
5822 		.priority =	NF_IP6_PRI_SELINUX_FIRST,
5823 	}
5824 };
5825 
5826 #endif	/* IPV6 */
5827 
5828 static int __init selinux_nf_ip_init(void)
5829 {
5830 	int err = 0;
5831 
5832 	if (!selinux_enabled)
5833 		goto out;
5834 
5835 	printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5836 
5837 	err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5838 	if (err)
5839 		panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5840 
5841 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5842 	err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5843 	if (err)
5844 		panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5845 #endif	/* IPV6 */
5846 
5847 out:
5848 	return err;
5849 }
5850 
5851 __initcall(selinux_nf_ip_init);
5852 
5853 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5854 static void selinux_nf_ip_exit(void)
5855 {
5856 	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5857 
5858 	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5859 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5860 	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5861 #endif	/* IPV6 */
5862 }
5863 #endif
5864 
5865 #else /* CONFIG_NETFILTER */
5866 
5867 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5868 #define selinux_nf_ip_exit()
5869 #endif
5870 
5871 #endif /* CONFIG_NETFILTER */
5872 
5873 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5874 static int selinux_disabled;
5875 
5876 int selinux_disable(void)
5877 {
5878 	if (ss_initialized) {
5879 		/* Not permitted after initial policy load. */
5880 		return -EINVAL;
5881 	}
5882 
5883 	if (selinux_disabled) {
5884 		/* Only do this once. */
5885 		return -EINVAL;
5886 	}
5887 
5888 	printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5889 
5890 	selinux_disabled = 1;
5891 	selinux_enabled = 0;
5892 
5893 	reset_security_ops();
5894 
5895 	/* Try to destroy the avc node cache */
5896 	avc_disable();
5897 
5898 	/* Unregister netfilter hooks. */
5899 	selinux_nf_ip_exit();
5900 
5901 	/* Unregister selinuxfs. */
5902 	exit_sel_fs();
5903 
5904 	return 0;
5905 }
5906 #endif
5907