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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/lsm_hooks.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/inet_connection_sock.h>
56#include <net/net_namespace.h>
57#include <net/netlabel.h>
58#include <linux/uaccess.h>
59#include <asm/ioctls.h>
60#include <linux/atomic.h>
61#include <linux/bitops.h>
62#include <linux/interrupt.h>
63#include <linux/netdevice.h> /* for network interface checks */
64#include <net/netlink.h>
65#include <linux/tcp.h>
66#include <linux/udp.h>
67#include <linux/dccp.h>
68#include <linux/quota.h>
69#include <linux/un.h> /* for Unix socket types */
70#include <net/af_unix.h> /* for Unix socket types */
71#include <linux/parser.h>
72#include <linux/nfs_mount.h>
73#include <net/ipv6.h>
74#include <linux/hugetlb.h>
75#include <linux/personality.h>
76#include <linux/audit.h>
77#include <linux/string.h>
78#include <linux/selinux.h>
79#include <linux/mutex.h>
80#include <linux/posix-timers.h>
81#include <linux/syslog.h>
82#include <linux/user_namespace.h>
83#include <linux/export.h>
84#include <linux/msg.h>
85#include <linux/shm.h>
86
87#include "avc.h"
88#include "objsec.h"
89#include "netif.h"
90#include "netnode.h"
91#include "netport.h"
92#include "xfrm.h"
93#include "netlabel.h"
94#include "audit.h"
95#include "avc_ss.h"
96
97/* SECMARK reference count */
98static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
99
100#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
101int selinux_enforcing;
102
103static int __init enforcing_setup(char *str)
104{
105 unsigned long enforcing;
106 if (!kstrtoul(str, 0, &enforcing))
107 selinux_enforcing = enforcing ? 1 : 0;
108 return 1;
109}
110__setup("enforcing=", enforcing_setup);
111#endif
112
113#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
114int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
115
116static int __init selinux_enabled_setup(char *str)
117{
118 unsigned long enabled;
119 if (!kstrtoul(str, 0, &enabled))
120 selinux_enabled = enabled ? 1 : 0;
121 return 1;
122}
123__setup("selinux=", selinux_enabled_setup);
124#else
125int selinux_enabled = 1;
126#endif
127
128static struct kmem_cache *sel_inode_cache;
129static struct kmem_cache *file_security_cache;
130
131/**
132 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
133 *
134 * Description:
135 * This function checks the SECMARK reference counter to see if any SECMARK
136 * targets are currently configured, if the reference counter is greater than
137 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
138 * enabled, false (0) if SECMARK is disabled. If the always_check_network
139 * policy capability is enabled, SECMARK is always considered enabled.
140 *
141 */
142static int selinux_secmark_enabled(void)
143{
144 return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
145}
146
147/**
148 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
149 *
150 * Description:
151 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true
152 * (1) if any are enabled or false (0) if neither are enabled. If the
153 * always_check_network policy capability is enabled, peer labeling
154 * is always considered enabled.
155 *
156 */
157static int selinux_peerlbl_enabled(void)
158{
159 return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
160}
161
162static int selinux_netcache_avc_callback(u32 event)
163{
164 if (event == AVC_CALLBACK_RESET) {
165 sel_netif_flush();
166 sel_netnode_flush();
167 sel_netport_flush();
168 synchronize_net();
169 }
170 return 0;
171}
172
173/*
174 * initialise the security for the init task
175 */
176static void cred_init_security(void)
177{
178 struct cred *cred = (struct cred *) current->real_cred;
179 struct task_security_struct *tsec;
180
181 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
182 if (!tsec)
183 panic("SELinux: Failed to initialize initial task.\n");
184
185 tsec->osid = tsec->sid = SECINITSID_KERNEL;
186 cred->security = tsec;
187}
188
189/*
190 * get the security ID of a set of credentials
191 */
192static inline u32 cred_sid(const struct cred *cred)
193{
194 const struct task_security_struct *tsec;
195
196 tsec = cred->security;
197 return tsec->sid;
198}
199
200/*
201 * get the objective security ID of a task
202 */
203static inline u32 task_sid(const struct task_struct *task)
204{
205 u32 sid;
206
207 rcu_read_lock();
208 sid = cred_sid(__task_cred(task));
209 rcu_read_unlock();
210 return sid;
211}
212
213/*
214 * get the subjective security ID of the current task
215 */
216static inline u32 current_sid(void)
217{
218 const struct task_security_struct *tsec = current_security();
219
220 return tsec->sid;
221}
222
223/* Allocate and free functions for each kind of security blob. */
224
225static int inode_alloc_security(struct inode *inode)
226{
227 struct inode_security_struct *isec;
228 u32 sid = current_sid();
229
230 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
231 if (!isec)
232 return -ENOMEM;
233
234 mutex_init(&isec->lock);
235 INIT_LIST_HEAD(&isec->list);
236 isec->inode = inode;
237 isec->sid = SECINITSID_UNLABELED;
238 isec->sclass = SECCLASS_FILE;
239 isec->task_sid = sid;
240 inode->i_security = isec;
241
242 return 0;
243}
244
245static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
246
247/*
248 * Try reloading inode security labels that have been marked as invalid. The
249 * @may_sleep parameter indicates when sleeping and thus reloading labels is
250 * allowed; when set to false, returns ERR_PTR(-ECHILD) when the label is
251 * invalid. The @opt_dentry parameter should be set to a dentry of the inode;
252 * when no dentry is available, set it to NULL instead.
253 */
254static int __inode_security_revalidate(struct inode *inode,
255 struct dentry *opt_dentry,
256 bool may_sleep)
257{
258 struct inode_security_struct *isec = inode->i_security;
259
260 might_sleep_if(may_sleep);
261
262 if (isec->initialized == LABEL_INVALID) {
263 if (!may_sleep)
264 return -ECHILD;
265
266 /*
267 * Try reloading the inode security label. This will fail if
268 * @opt_dentry is NULL and no dentry for this inode can be
269 * found; in that case, continue using the old label.
270 */
271 inode_doinit_with_dentry(inode, opt_dentry);
272 }
273 return 0;
274}
275
276static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
277{
278 return inode->i_security;
279}
280
281static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
282{
283 int error;
284
285 error = __inode_security_revalidate(inode, NULL, !rcu);
286 if (error)
287 return ERR_PTR(error);
288 return inode->i_security;
289}
290
291/*
292 * Get the security label of an inode.
293 */
294static struct inode_security_struct *inode_security(struct inode *inode)
295{
296 __inode_security_revalidate(inode, NULL, true);
297 return inode->i_security;
298}
299
300/*
301 * Get the security label of a dentry's backing inode.
302 */
303static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
304{
305 struct inode *inode = d_backing_inode(dentry);
306
307 __inode_security_revalidate(inode, dentry, true);
308 return inode->i_security;
309}
310
311static void inode_free_rcu(struct rcu_head *head)
312{
313 struct inode_security_struct *isec;
314
315 isec = container_of(head, struct inode_security_struct, rcu);
316 kmem_cache_free(sel_inode_cache, isec);
317}
318
319static void inode_free_security(struct inode *inode)
320{
321 struct inode_security_struct *isec = inode->i_security;
322 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
323
324 /*
325 * As not all inode security structures are in a list, we check for
326 * empty list outside of the lock to make sure that we won't waste
327 * time taking a lock doing nothing.
328 *
329 * The list_del_init() function can be safely called more than once.
330 * It should not be possible for this function to be called with
331 * concurrent list_add(), but for better safety against future changes
332 * in the code, we use list_empty_careful() here.
333 */
334 if (!list_empty_careful(&isec->list)) {
335 spin_lock(&sbsec->isec_lock);
336 list_del_init(&isec->list);
337 spin_unlock(&sbsec->isec_lock);
338 }
339
340 /*
341 * The inode may still be referenced in a path walk and
342 * a call to selinux_inode_permission() can be made
343 * after inode_free_security() is called. Ideally, the VFS
344 * wouldn't do this, but fixing that is a much harder
345 * job. For now, simply free the i_security via RCU, and
346 * leave the current inode->i_security pointer intact.
347 * The inode will be freed after the RCU grace period too.
348 */
349 call_rcu(&isec->rcu, inode_free_rcu);
350}
351
352static int file_alloc_security(struct file *file)
353{
354 struct file_security_struct *fsec;
355 u32 sid = current_sid();
356
357 fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
358 if (!fsec)
359 return -ENOMEM;
360
361 fsec->sid = sid;
362 fsec->fown_sid = sid;
363 file->f_security = fsec;
364
365 return 0;
366}
367
368static void file_free_security(struct file *file)
369{
370 struct file_security_struct *fsec = file->f_security;
371 file->f_security = NULL;
372 kmem_cache_free(file_security_cache, fsec);
373}
374
375static int superblock_alloc_security(struct super_block *sb)
376{
377 struct superblock_security_struct *sbsec;
378
379 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
380 if (!sbsec)
381 return -ENOMEM;
382
383 mutex_init(&sbsec->lock);
384 INIT_LIST_HEAD(&sbsec->isec_head);
385 spin_lock_init(&sbsec->isec_lock);
386 sbsec->sb = sb;
387 sbsec->sid = SECINITSID_UNLABELED;
388 sbsec->def_sid = SECINITSID_FILE;
389 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
390 sb->s_security = sbsec;
391
392 return 0;
393}
394
395static void superblock_free_security(struct super_block *sb)
396{
397 struct superblock_security_struct *sbsec = sb->s_security;
398 sb->s_security = NULL;
399 kfree(sbsec);
400}
401
402/* The file system's label must be initialized prior to use. */
403
404static const char *labeling_behaviors[7] = {
405 "uses xattr",
406 "uses transition SIDs",
407 "uses task SIDs",
408 "uses genfs_contexts",
409 "not configured for labeling",
410 "uses mountpoint labeling",
411 "uses native labeling",
412};
413
414static inline int inode_doinit(struct inode *inode)
415{
416 return inode_doinit_with_dentry(inode, NULL);
417}
418
419enum {
420 Opt_error = -1,
421 Opt_context = 1,
422 Opt_fscontext = 2,
423 Opt_defcontext = 3,
424 Opt_rootcontext = 4,
425 Opt_labelsupport = 5,
426 Opt_nextmntopt = 6,
427};
428
429#define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1)
430
431static const match_table_t tokens = {
432 {Opt_context, CONTEXT_STR "%s"},
433 {Opt_fscontext, FSCONTEXT_STR "%s"},
434 {Opt_defcontext, DEFCONTEXT_STR "%s"},
435 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
436 {Opt_labelsupport, LABELSUPP_STR},
437 {Opt_error, NULL},
438};
439
440#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
441
442static int may_context_mount_sb_relabel(u32 sid,
443 struct superblock_security_struct *sbsec,
444 const struct cred *cred)
445{
446 const struct task_security_struct *tsec = cred->security;
447 int rc;
448
449 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
450 FILESYSTEM__RELABELFROM, NULL);
451 if (rc)
452 return rc;
453
454 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
455 FILESYSTEM__RELABELTO, NULL);
456 return rc;
457}
458
459static int may_context_mount_inode_relabel(u32 sid,
460 struct superblock_security_struct *sbsec,
461 const struct cred *cred)
462{
463 const struct task_security_struct *tsec = cred->security;
464 int rc;
465 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
466 FILESYSTEM__RELABELFROM, NULL);
467 if (rc)
468 return rc;
469
470 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
471 FILESYSTEM__ASSOCIATE, NULL);
472 return rc;
473}
474
475static int selinux_is_sblabel_mnt(struct super_block *sb)
476{
477 struct superblock_security_struct *sbsec = sb->s_security;
478
479 return sbsec->behavior == SECURITY_FS_USE_XATTR ||
480 sbsec->behavior == SECURITY_FS_USE_TRANS ||
481 sbsec->behavior == SECURITY_FS_USE_TASK ||
482 sbsec->behavior == SECURITY_FS_USE_NATIVE ||
483 /* Special handling. Genfs but also in-core setxattr handler */
484 !strcmp(sb->s_type->name, "sysfs") ||
485 !strcmp(sb->s_type->name, "pstore") ||
486 !strcmp(sb->s_type->name, "debugfs") ||
487 !strcmp(sb->s_type->name, "rootfs");
488}
489
490static int sb_finish_set_opts(struct super_block *sb)
491{
492 struct superblock_security_struct *sbsec = sb->s_security;
493 struct dentry *root = sb->s_root;
494 struct inode *root_inode = d_backing_inode(root);
495 int rc = 0;
496
497 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
498 /* Make sure that the xattr handler exists and that no
499 error other than -ENODATA is returned by getxattr on
500 the root directory. -ENODATA is ok, as this may be
501 the first boot of the SELinux kernel before we have
502 assigned xattr values to the filesystem. */
503 if (!root_inode->i_op->getxattr) {
504 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
505 "xattr support\n", sb->s_id, sb->s_type->name);
506 rc = -EOPNOTSUPP;
507 goto out;
508 }
509 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
510 if (rc < 0 && rc != -ENODATA) {
511 if (rc == -EOPNOTSUPP)
512 printk(KERN_WARNING "SELinux: (dev %s, type "
513 "%s) has no security xattr handler\n",
514 sb->s_id, sb->s_type->name);
515 else
516 printk(KERN_WARNING "SELinux: (dev %s, type "
517 "%s) getxattr errno %d\n", sb->s_id,
518 sb->s_type->name, -rc);
519 goto out;
520 }
521 }
522
523 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
524 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
525 sb->s_id, sb->s_type->name);
526
527 sbsec->flags |= SE_SBINITIALIZED;
528 if (selinux_is_sblabel_mnt(sb))
529 sbsec->flags |= SBLABEL_MNT;
530
531 /* Initialize the root inode. */
532 rc = inode_doinit_with_dentry(root_inode, root);
533
534 /* Initialize any other inodes associated with the superblock, e.g.
535 inodes created prior to initial policy load or inodes created
536 during get_sb by a pseudo filesystem that directly
537 populates itself. */
538 spin_lock(&sbsec->isec_lock);
539next_inode:
540 if (!list_empty(&sbsec->isec_head)) {
541 struct inode_security_struct *isec =
542 list_entry(sbsec->isec_head.next,
543 struct inode_security_struct, list);
544 struct inode *inode = isec->inode;
545 list_del_init(&isec->list);
546 spin_unlock(&sbsec->isec_lock);
547 inode = igrab(inode);
548 if (inode) {
549 if (!IS_PRIVATE(inode))
550 inode_doinit(inode);
551 iput(inode);
552 }
553 spin_lock(&sbsec->isec_lock);
554 goto next_inode;
555 }
556 spin_unlock(&sbsec->isec_lock);
557out:
558 return rc;
559}
560
561/*
562 * This function should allow an FS to ask what it's mount security
563 * options were so it can use those later for submounts, displaying
564 * mount options, or whatever.
565 */
566static int selinux_get_mnt_opts(const struct super_block *sb,
567 struct security_mnt_opts *opts)
568{
569 int rc = 0, i;
570 struct superblock_security_struct *sbsec = sb->s_security;
571 char *context = NULL;
572 u32 len;
573 char tmp;
574
575 security_init_mnt_opts(opts);
576
577 if (!(sbsec->flags & SE_SBINITIALIZED))
578 return -EINVAL;
579
580 if (!ss_initialized)
581 return -EINVAL;
582
583 /* make sure we always check enough bits to cover the mask */
584 BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
585
586 tmp = sbsec->flags & SE_MNTMASK;
587 /* count the number of mount options for this sb */
588 for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
589 if (tmp & 0x01)
590 opts->num_mnt_opts++;
591 tmp >>= 1;
592 }
593 /* Check if the Label support flag is set */
594 if (sbsec->flags & SBLABEL_MNT)
595 opts->num_mnt_opts++;
596
597 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
598 if (!opts->mnt_opts) {
599 rc = -ENOMEM;
600 goto out_free;
601 }
602
603 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
604 if (!opts->mnt_opts_flags) {
605 rc = -ENOMEM;
606 goto out_free;
607 }
608
609 i = 0;
610 if (sbsec->flags & FSCONTEXT_MNT) {
611 rc = security_sid_to_context(sbsec->sid, &context, &len);
612 if (rc)
613 goto out_free;
614 opts->mnt_opts[i] = context;
615 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
616 }
617 if (sbsec->flags & CONTEXT_MNT) {
618 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
619 if (rc)
620 goto out_free;
621 opts->mnt_opts[i] = context;
622 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
623 }
624 if (sbsec->flags & DEFCONTEXT_MNT) {
625 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
626 if (rc)
627 goto out_free;
628 opts->mnt_opts[i] = context;
629 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
630 }
631 if (sbsec->flags & ROOTCONTEXT_MNT) {
632 struct dentry *root = sbsec->sb->s_root;
633 struct inode_security_struct *isec = backing_inode_security(root);
634
635 rc = security_sid_to_context(isec->sid, &context, &len);
636 if (rc)
637 goto out_free;
638 opts->mnt_opts[i] = context;
639 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
640 }
641 if (sbsec->flags & SBLABEL_MNT) {
642 opts->mnt_opts[i] = NULL;
643 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
644 }
645
646 BUG_ON(i != opts->num_mnt_opts);
647
648 return 0;
649
650out_free:
651 security_free_mnt_opts(opts);
652 return rc;
653}
654
655static int bad_option(struct superblock_security_struct *sbsec, char flag,
656 u32 old_sid, u32 new_sid)
657{
658 char mnt_flags = sbsec->flags & SE_MNTMASK;
659
660 /* check if the old mount command had the same options */
661 if (sbsec->flags & SE_SBINITIALIZED)
662 if (!(sbsec->flags & flag) ||
663 (old_sid != new_sid))
664 return 1;
665
666 /* check if we were passed the same options twice,
667 * aka someone passed context=a,context=b
668 */
669 if (!(sbsec->flags & SE_SBINITIALIZED))
670 if (mnt_flags & flag)
671 return 1;
672 return 0;
673}
674
675/*
676 * Allow filesystems with binary mount data to explicitly set mount point
677 * labeling information.
678 */
679static int selinux_set_mnt_opts(struct super_block *sb,
680 struct security_mnt_opts *opts,
681 unsigned long kern_flags,
682 unsigned long *set_kern_flags)
683{
684 const struct cred *cred = current_cred();
685 int rc = 0, i;
686 struct superblock_security_struct *sbsec = sb->s_security;
687 const char *name = sb->s_type->name;
688 struct dentry *root = sbsec->sb->s_root;
689 struct inode_security_struct *root_isec = backing_inode_security(root);
690 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
691 u32 defcontext_sid = 0;
692 char **mount_options = opts->mnt_opts;
693 int *flags = opts->mnt_opts_flags;
694 int num_opts = opts->num_mnt_opts;
695
696 mutex_lock(&sbsec->lock);
697
698 if (!ss_initialized) {
699 if (!num_opts) {
700 /* Defer initialization until selinux_complete_init,
701 after the initial policy is loaded and the security
702 server is ready to handle calls. */
703 goto out;
704 }
705 rc = -EINVAL;
706 printk(KERN_WARNING "SELinux: Unable to set superblock options "
707 "before the security server is initialized\n");
708 goto out;
709 }
710 if (kern_flags && !set_kern_flags) {
711 /* Specifying internal flags without providing a place to
712 * place the results is not allowed */
713 rc = -EINVAL;
714 goto out;
715 }
716
717 /*
718 * Binary mount data FS will come through this function twice. Once
719 * from an explicit call and once from the generic calls from the vfs.
720 * Since the generic VFS calls will not contain any security mount data
721 * we need to skip the double mount verification.
722 *
723 * This does open a hole in which we will not notice if the first
724 * mount using this sb set explict options and a second mount using
725 * this sb does not set any security options. (The first options
726 * will be used for both mounts)
727 */
728 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
729 && (num_opts == 0))
730 goto out;
731
732 /*
733 * parse the mount options, check if they are valid sids.
734 * also check if someone is trying to mount the same sb more
735 * than once with different security options.
736 */
737 for (i = 0; i < num_opts; i++) {
738 u32 sid;
739
740 if (flags[i] == SBLABEL_MNT)
741 continue;
742 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
743 if (rc) {
744 printk(KERN_WARNING "SELinux: security_context_str_to_sid"
745 "(%s) failed for (dev %s, type %s) errno=%d\n",
746 mount_options[i], sb->s_id, name, rc);
747 goto out;
748 }
749 switch (flags[i]) {
750 case FSCONTEXT_MNT:
751 fscontext_sid = sid;
752
753 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
754 fscontext_sid))
755 goto out_double_mount;
756
757 sbsec->flags |= FSCONTEXT_MNT;
758 break;
759 case CONTEXT_MNT:
760 context_sid = sid;
761
762 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
763 context_sid))
764 goto out_double_mount;
765
766 sbsec->flags |= CONTEXT_MNT;
767 break;
768 case ROOTCONTEXT_MNT:
769 rootcontext_sid = sid;
770
771 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
772 rootcontext_sid))
773 goto out_double_mount;
774
775 sbsec->flags |= ROOTCONTEXT_MNT;
776
777 break;
778 case DEFCONTEXT_MNT:
779 defcontext_sid = sid;
780
781 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
782 defcontext_sid))
783 goto out_double_mount;
784
785 sbsec->flags |= DEFCONTEXT_MNT;
786
787 break;
788 default:
789 rc = -EINVAL;
790 goto out;
791 }
792 }
793
794 if (sbsec->flags & SE_SBINITIALIZED) {
795 /* previously mounted with options, but not on this attempt? */
796 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
797 goto out_double_mount;
798 rc = 0;
799 goto out;
800 }
801
802 if (strcmp(sb->s_type->name, "proc") == 0)
803 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
804
805 if (!strcmp(sb->s_type->name, "debugfs") ||
806 !strcmp(sb->s_type->name, "sysfs") ||
807 !strcmp(sb->s_type->name, "pstore"))
808 sbsec->flags |= SE_SBGENFS;
809
810 if (!sbsec->behavior) {
811 /*
812 * Determine the labeling behavior to use for this
813 * filesystem type.
814 */
815 rc = security_fs_use(sb);
816 if (rc) {
817 printk(KERN_WARNING
818 "%s: security_fs_use(%s) returned %d\n",
819 __func__, sb->s_type->name, rc);
820 goto out;
821 }
822 }
823 /* sets the context of the superblock for the fs being mounted. */
824 if (fscontext_sid) {
825 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
826 if (rc)
827 goto out;
828
829 sbsec->sid = fscontext_sid;
830 }
831
832 /*
833 * Switch to using mount point labeling behavior.
834 * sets the label used on all file below the mountpoint, and will set
835 * the superblock context if not already set.
836 */
837 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
838 sbsec->behavior = SECURITY_FS_USE_NATIVE;
839 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
840 }
841
842 if (context_sid) {
843 if (!fscontext_sid) {
844 rc = may_context_mount_sb_relabel(context_sid, sbsec,
845 cred);
846 if (rc)
847 goto out;
848 sbsec->sid = context_sid;
849 } else {
850 rc = may_context_mount_inode_relabel(context_sid, sbsec,
851 cred);
852 if (rc)
853 goto out;
854 }
855 if (!rootcontext_sid)
856 rootcontext_sid = context_sid;
857
858 sbsec->mntpoint_sid = context_sid;
859 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
860 }
861
862 if (rootcontext_sid) {
863 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
864 cred);
865 if (rc)
866 goto out;
867
868 root_isec->sid = rootcontext_sid;
869 root_isec->initialized = LABEL_INITIALIZED;
870 }
871
872 if (defcontext_sid) {
873 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
874 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
875 rc = -EINVAL;
876 printk(KERN_WARNING "SELinux: defcontext option is "
877 "invalid for this filesystem type\n");
878 goto out;
879 }
880
881 if (defcontext_sid != sbsec->def_sid) {
882 rc = may_context_mount_inode_relabel(defcontext_sid,
883 sbsec, cred);
884 if (rc)
885 goto out;
886 }
887
888 sbsec->def_sid = defcontext_sid;
889 }
890
891 rc = sb_finish_set_opts(sb);
892out:
893 mutex_unlock(&sbsec->lock);
894 return rc;
895out_double_mount:
896 rc = -EINVAL;
897 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
898 "security settings for (dev %s, type %s)\n", sb->s_id, name);
899 goto out;
900}
901
902static int selinux_cmp_sb_context(const struct super_block *oldsb,
903 const struct super_block *newsb)
904{
905 struct superblock_security_struct *old = oldsb->s_security;
906 struct superblock_security_struct *new = newsb->s_security;
907 char oldflags = old->flags & SE_MNTMASK;
908 char newflags = new->flags & SE_MNTMASK;
909
910 if (oldflags != newflags)
911 goto mismatch;
912 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
913 goto mismatch;
914 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
915 goto mismatch;
916 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
917 goto mismatch;
918 if (oldflags & ROOTCONTEXT_MNT) {
919 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
920 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
921 if (oldroot->sid != newroot->sid)
922 goto mismatch;
923 }
924 return 0;
925mismatch:
926 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, "
927 "different security settings for (dev %s, "
928 "type %s)\n", newsb->s_id, newsb->s_type->name);
929 return -EBUSY;
930}
931
932static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
933 struct super_block *newsb)
934{
935 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
936 struct superblock_security_struct *newsbsec = newsb->s_security;
937
938 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
939 int set_context = (oldsbsec->flags & CONTEXT_MNT);
940 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
941
942 /*
943 * if the parent was able to be mounted it clearly had no special lsm
944 * mount options. thus we can safely deal with this superblock later
945 */
946 if (!ss_initialized)
947 return 0;
948
949 /* how can we clone if the old one wasn't set up?? */
950 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
951
952 /* if fs is reusing a sb, make sure that the contexts match */
953 if (newsbsec->flags & SE_SBINITIALIZED)
954 return selinux_cmp_sb_context(oldsb, newsb);
955
956 mutex_lock(&newsbsec->lock);
957
958 newsbsec->flags = oldsbsec->flags;
959
960 newsbsec->sid = oldsbsec->sid;
961 newsbsec->def_sid = oldsbsec->def_sid;
962 newsbsec->behavior = oldsbsec->behavior;
963
964 if (set_context) {
965 u32 sid = oldsbsec->mntpoint_sid;
966
967 if (!set_fscontext)
968 newsbsec->sid = sid;
969 if (!set_rootcontext) {
970 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
971 newisec->sid = sid;
972 }
973 newsbsec->mntpoint_sid = sid;
974 }
975 if (set_rootcontext) {
976 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
977 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
978
979 newisec->sid = oldisec->sid;
980 }
981
982 sb_finish_set_opts(newsb);
983 mutex_unlock(&newsbsec->lock);
984 return 0;
985}
986
987static int selinux_parse_opts_str(char *options,
988 struct security_mnt_opts *opts)
989{
990 char *p;
991 char *context = NULL, *defcontext = NULL;
992 char *fscontext = NULL, *rootcontext = NULL;
993 int rc, num_mnt_opts = 0;
994
995 opts->num_mnt_opts = 0;
996
997 /* Standard string-based options. */
998 while ((p = strsep(&options, "|")) != NULL) {
999 int token;
1000 substring_t args[MAX_OPT_ARGS];
1001
1002 if (!*p)
1003 continue;
1004
1005 token = match_token(p, tokens, args);
1006
1007 switch (token) {
1008 case Opt_context:
1009 if (context || defcontext) {
1010 rc = -EINVAL;
1011 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1012 goto out_err;
1013 }
1014 context = match_strdup(&args[0]);
1015 if (!context) {
1016 rc = -ENOMEM;
1017 goto out_err;
1018 }
1019 break;
1020
1021 case Opt_fscontext:
1022 if (fscontext) {
1023 rc = -EINVAL;
1024 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1025 goto out_err;
1026 }
1027 fscontext = match_strdup(&args[0]);
1028 if (!fscontext) {
1029 rc = -ENOMEM;
1030 goto out_err;
1031 }
1032 break;
1033
1034 case Opt_rootcontext:
1035 if (rootcontext) {
1036 rc = -EINVAL;
1037 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1038 goto out_err;
1039 }
1040 rootcontext = match_strdup(&args[0]);
1041 if (!rootcontext) {
1042 rc = -ENOMEM;
1043 goto out_err;
1044 }
1045 break;
1046
1047 case Opt_defcontext:
1048 if (context || defcontext) {
1049 rc = -EINVAL;
1050 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1051 goto out_err;
1052 }
1053 defcontext = match_strdup(&args[0]);
1054 if (!defcontext) {
1055 rc = -ENOMEM;
1056 goto out_err;
1057 }
1058 break;
1059 case Opt_labelsupport:
1060 break;
1061 default:
1062 rc = -EINVAL;
1063 printk(KERN_WARNING "SELinux: unknown mount option\n");
1064 goto out_err;
1065
1066 }
1067 }
1068
1069 rc = -ENOMEM;
1070 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
1071 if (!opts->mnt_opts)
1072 goto out_err;
1073
1074 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
1075 if (!opts->mnt_opts_flags) {
1076 kfree(opts->mnt_opts);
1077 goto out_err;
1078 }
1079
1080 if (fscontext) {
1081 opts->mnt_opts[num_mnt_opts] = fscontext;
1082 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1083 }
1084 if (context) {
1085 opts->mnt_opts[num_mnt_opts] = context;
1086 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1087 }
1088 if (rootcontext) {
1089 opts->mnt_opts[num_mnt_opts] = rootcontext;
1090 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1091 }
1092 if (defcontext) {
1093 opts->mnt_opts[num_mnt_opts] = defcontext;
1094 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1095 }
1096
1097 opts->num_mnt_opts = num_mnt_opts;
1098 return 0;
1099
1100out_err:
1101 kfree(context);
1102 kfree(defcontext);
1103 kfree(fscontext);
1104 kfree(rootcontext);
1105 return rc;
1106}
1107/*
1108 * string mount options parsing and call set the sbsec
1109 */
1110static int superblock_doinit(struct super_block *sb, void *data)
1111{
1112 int rc = 0;
1113 char *options = data;
1114 struct security_mnt_opts opts;
1115
1116 security_init_mnt_opts(&opts);
1117
1118 if (!data)
1119 goto out;
1120
1121 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1122
1123 rc = selinux_parse_opts_str(options, &opts);
1124 if (rc)
1125 goto out_err;
1126
1127out:
1128 rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1129
1130out_err:
1131 security_free_mnt_opts(&opts);
1132 return rc;
1133}
1134
1135static void selinux_write_opts(struct seq_file *m,
1136 struct security_mnt_opts *opts)
1137{
1138 int i;
1139 char *prefix;
1140
1141 for (i = 0; i < opts->num_mnt_opts; i++) {
1142 char *has_comma;
1143
1144 if (opts->mnt_opts[i])
1145 has_comma = strchr(opts->mnt_opts[i], ',');
1146 else
1147 has_comma = NULL;
1148
1149 switch (opts->mnt_opts_flags[i]) {
1150 case CONTEXT_MNT:
1151 prefix = CONTEXT_STR;
1152 break;
1153 case FSCONTEXT_MNT:
1154 prefix = FSCONTEXT_STR;
1155 break;
1156 case ROOTCONTEXT_MNT:
1157 prefix = ROOTCONTEXT_STR;
1158 break;
1159 case DEFCONTEXT_MNT:
1160 prefix = DEFCONTEXT_STR;
1161 break;
1162 case SBLABEL_MNT:
1163 seq_putc(m, ',');
1164 seq_puts(m, LABELSUPP_STR);
1165 continue;
1166 default:
1167 BUG();
1168 return;
1169 };
1170 /* we need a comma before each option */
1171 seq_putc(m, ',');
1172 seq_puts(m, prefix);
1173 if (has_comma)
1174 seq_putc(m, '\"');
1175 seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1176 if (has_comma)
1177 seq_putc(m, '\"');
1178 }
1179}
1180
1181static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1182{
1183 struct security_mnt_opts opts;
1184 int rc;
1185
1186 rc = selinux_get_mnt_opts(sb, &opts);
1187 if (rc) {
1188 /* before policy load we may get EINVAL, don't show anything */
1189 if (rc == -EINVAL)
1190 rc = 0;
1191 return rc;
1192 }
1193
1194 selinux_write_opts(m, &opts);
1195
1196 security_free_mnt_opts(&opts);
1197
1198 return rc;
1199}
1200
1201static inline u16 inode_mode_to_security_class(umode_t mode)
1202{
1203 switch (mode & S_IFMT) {
1204 case S_IFSOCK:
1205 return SECCLASS_SOCK_FILE;
1206 case S_IFLNK:
1207 return SECCLASS_LNK_FILE;
1208 case S_IFREG:
1209 return SECCLASS_FILE;
1210 case S_IFBLK:
1211 return SECCLASS_BLK_FILE;
1212 case S_IFDIR:
1213 return SECCLASS_DIR;
1214 case S_IFCHR:
1215 return SECCLASS_CHR_FILE;
1216 case S_IFIFO:
1217 return SECCLASS_FIFO_FILE;
1218
1219 }
1220
1221 return SECCLASS_FILE;
1222}
1223
1224static inline int default_protocol_stream(int protocol)
1225{
1226 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1227}
1228
1229static inline int default_protocol_dgram(int protocol)
1230{
1231 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1232}
1233
1234static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1235{
1236 switch (family) {
1237 case PF_UNIX:
1238 switch (type) {
1239 case SOCK_STREAM:
1240 case SOCK_SEQPACKET:
1241 return SECCLASS_UNIX_STREAM_SOCKET;
1242 case SOCK_DGRAM:
1243 return SECCLASS_UNIX_DGRAM_SOCKET;
1244 }
1245 break;
1246 case PF_INET:
1247 case PF_INET6:
1248 switch (type) {
1249 case SOCK_STREAM:
1250 if (default_protocol_stream(protocol))
1251 return SECCLASS_TCP_SOCKET;
1252 else
1253 return SECCLASS_RAWIP_SOCKET;
1254 case SOCK_DGRAM:
1255 if (default_protocol_dgram(protocol))
1256 return SECCLASS_UDP_SOCKET;
1257 else
1258 return SECCLASS_RAWIP_SOCKET;
1259 case SOCK_DCCP:
1260 return SECCLASS_DCCP_SOCKET;
1261 default:
1262 return SECCLASS_RAWIP_SOCKET;
1263 }
1264 break;
1265 case PF_NETLINK:
1266 switch (protocol) {
1267 case NETLINK_ROUTE:
1268 return SECCLASS_NETLINK_ROUTE_SOCKET;
1269 case NETLINK_SOCK_DIAG:
1270 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1271 case NETLINK_NFLOG:
1272 return SECCLASS_NETLINK_NFLOG_SOCKET;
1273 case NETLINK_XFRM:
1274 return SECCLASS_NETLINK_XFRM_SOCKET;
1275 case NETLINK_SELINUX:
1276 return SECCLASS_NETLINK_SELINUX_SOCKET;
1277 case NETLINK_ISCSI:
1278 return SECCLASS_NETLINK_ISCSI_SOCKET;
1279 case NETLINK_AUDIT:
1280 return SECCLASS_NETLINK_AUDIT_SOCKET;
1281 case NETLINK_FIB_LOOKUP:
1282 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1283 case NETLINK_CONNECTOR:
1284 return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1285 case NETLINK_NETFILTER:
1286 return SECCLASS_NETLINK_NETFILTER_SOCKET;
1287 case NETLINK_DNRTMSG:
1288 return SECCLASS_NETLINK_DNRT_SOCKET;
1289 case NETLINK_KOBJECT_UEVENT:
1290 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1291 case NETLINK_GENERIC:
1292 return SECCLASS_NETLINK_GENERIC_SOCKET;
1293 case NETLINK_SCSITRANSPORT:
1294 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1295 case NETLINK_RDMA:
1296 return SECCLASS_NETLINK_RDMA_SOCKET;
1297 case NETLINK_CRYPTO:
1298 return SECCLASS_NETLINK_CRYPTO_SOCKET;
1299 default:
1300 return SECCLASS_NETLINK_SOCKET;
1301 }
1302 case PF_PACKET:
1303 return SECCLASS_PACKET_SOCKET;
1304 case PF_KEY:
1305 return SECCLASS_KEY_SOCKET;
1306 case PF_APPLETALK:
1307 return SECCLASS_APPLETALK_SOCKET;
1308 }
1309
1310 return SECCLASS_SOCKET;
1311}
1312
1313static int selinux_genfs_get_sid(struct dentry *dentry,
1314 u16 tclass,
1315 u16 flags,
1316 u32 *sid)
1317{
1318 int rc;
1319 struct super_block *sb = dentry->d_inode->i_sb;
1320 char *buffer, *path;
1321
1322 buffer = (char *)__get_free_page(GFP_KERNEL);
1323 if (!buffer)
1324 return -ENOMEM;
1325
1326 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1327 if (IS_ERR(path))
1328 rc = PTR_ERR(path);
1329 else {
1330 if (flags & SE_SBPROC) {
1331 /* each process gets a /proc/PID/ entry. Strip off the
1332 * PID part to get a valid selinux labeling.
1333 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1334 while (path[1] >= '0' && path[1] <= '9') {
1335 path[1] = '/';
1336 path++;
1337 }
1338 }
1339 rc = security_genfs_sid(sb->s_type->name, path, tclass, sid);
1340 }
1341 free_page((unsigned long)buffer);
1342 return rc;
1343}
1344
1345/* The inode's security attributes must be initialized before first use. */
1346static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1347{
1348 struct superblock_security_struct *sbsec = NULL;
1349 struct inode_security_struct *isec = inode->i_security;
1350 u32 sid;
1351 struct dentry *dentry;
1352#define INITCONTEXTLEN 255
1353 char *context = NULL;
1354 unsigned len = 0;
1355 int rc = 0;
1356
1357 if (isec->initialized == LABEL_INITIALIZED)
1358 goto out;
1359
1360 mutex_lock(&isec->lock);
1361 if (isec->initialized == LABEL_INITIALIZED)
1362 goto out_unlock;
1363
1364 sbsec = inode->i_sb->s_security;
1365 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1366 /* Defer initialization until selinux_complete_init,
1367 after the initial policy is loaded and the security
1368 server is ready to handle calls. */
1369 spin_lock(&sbsec->isec_lock);
1370 if (list_empty(&isec->list))
1371 list_add(&isec->list, &sbsec->isec_head);
1372 spin_unlock(&sbsec->isec_lock);
1373 goto out_unlock;
1374 }
1375
1376 switch (sbsec->behavior) {
1377 case SECURITY_FS_USE_NATIVE:
1378 break;
1379 case SECURITY_FS_USE_XATTR:
1380 if (!inode->i_op->getxattr) {
1381 isec->sid = sbsec->def_sid;
1382 break;
1383 }
1384
1385 /* Need a dentry, since the xattr API requires one.
1386 Life would be simpler if we could just pass the inode. */
1387 if (opt_dentry) {
1388 /* Called from d_instantiate or d_splice_alias. */
1389 dentry = dget(opt_dentry);
1390 } else {
1391 /* Called from selinux_complete_init, try to find a dentry. */
1392 dentry = d_find_alias(inode);
1393 }
1394 if (!dentry) {
1395 /*
1396 * this is can be hit on boot when a file is accessed
1397 * before the policy is loaded. When we load policy we
1398 * may find inodes that have no dentry on the
1399 * sbsec->isec_head list. No reason to complain as these
1400 * will get fixed up the next time we go through
1401 * inode_doinit with a dentry, before these inodes could
1402 * be used again by userspace.
1403 */
1404 goto out_unlock;
1405 }
1406
1407 len = INITCONTEXTLEN;
1408 context = kmalloc(len+1, GFP_NOFS);
1409 if (!context) {
1410 rc = -ENOMEM;
1411 dput(dentry);
1412 goto out_unlock;
1413 }
1414 context[len] = '\0';
1415 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1416 context, len);
1417 if (rc == -ERANGE) {
1418 kfree(context);
1419
1420 /* Need a larger buffer. Query for the right size. */
1421 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1422 NULL, 0);
1423 if (rc < 0) {
1424 dput(dentry);
1425 goto out_unlock;
1426 }
1427 len = rc;
1428 context = kmalloc(len+1, GFP_NOFS);
1429 if (!context) {
1430 rc = -ENOMEM;
1431 dput(dentry);
1432 goto out_unlock;
1433 }
1434 context[len] = '\0';
1435 rc = inode->i_op->getxattr(dentry,
1436 XATTR_NAME_SELINUX,
1437 context, len);
1438 }
1439 dput(dentry);
1440 if (rc < 0) {
1441 if (rc != -ENODATA) {
1442 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1443 "%d for dev=%s ino=%ld\n", __func__,
1444 -rc, inode->i_sb->s_id, inode->i_ino);
1445 kfree(context);
1446 goto out_unlock;
1447 }
1448 /* Map ENODATA to the default file SID */
1449 sid = sbsec->def_sid;
1450 rc = 0;
1451 } else {
1452 rc = security_context_to_sid_default(context, rc, &sid,
1453 sbsec->def_sid,
1454 GFP_NOFS);
1455 if (rc) {
1456 char *dev = inode->i_sb->s_id;
1457 unsigned long ino = inode->i_ino;
1458
1459 if (rc == -EINVAL) {
1460 if (printk_ratelimit())
1461 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1462 "context=%s. This indicates you may need to relabel the inode or the "
1463 "filesystem in question.\n", ino, dev, context);
1464 } else {
1465 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1466 "returned %d for dev=%s ino=%ld\n",
1467 __func__, context, -rc, dev, ino);
1468 }
1469 kfree(context);
1470 /* Leave with the unlabeled SID */
1471 rc = 0;
1472 break;
1473 }
1474 }
1475 kfree(context);
1476 isec->sid = sid;
1477 break;
1478 case SECURITY_FS_USE_TASK:
1479 isec->sid = isec->task_sid;
1480 break;
1481 case SECURITY_FS_USE_TRANS:
1482 /* Default to the fs SID. */
1483 isec->sid = sbsec->sid;
1484
1485 /* Try to obtain a transition SID. */
1486 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1487 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1488 isec->sclass, NULL, &sid);
1489 if (rc)
1490 goto out_unlock;
1491 isec->sid = sid;
1492 break;
1493 case SECURITY_FS_USE_MNTPOINT:
1494 isec->sid = sbsec->mntpoint_sid;
1495 break;
1496 default:
1497 /* Default to the fs superblock SID. */
1498 isec->sid = sbsec->sid;
1499
1500 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1501 /* We must have a dentry to determine the label on
1502 * procfs inodes */
1503 if (opt_dentry)
1504 /* Called from d_instantiate or
1505 * d_splice_alias. */
1506 dentry = dget(opt_dentry);
1507 else
1508 /* Called from selinux_complete_init, try to
1509 * find a dentry. */
1510 dentry = d_find_alias(inode);
1511 /*
1512 * This can be hit on boot when a file is accessed
1513 * before the policy is loaded. When we load policy we
1514 * may find inodes that have no dentry on the
1515 * sbsec->isec_head list. No reason to complain as
1516 * these will get fixed up the next time we go through
1517 * inode_doinit() with a dentry, before these inodes
1518 * could be used again by userspace.
1519 */
1520 if (!dentry)
1521 goto out_unlock;
1522 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1523 rc = selinux_genfs_get_sid(dentry, isec->sclass,
1524 sbsec->flags, &sid);
1525 dput(dentry);
1526 if (rc)
1527 goto out_unlock;
1528 isec->sid = sid;
1529 }
1530 break;
1531 }
1532
1533 isec->initialized = LABEL_INITIALIZED;
1534
1535out_unlock:
1536 mutex_unlock(&isec->lock);
1537out:
1538 if (isec->sclass == SECCLASS_FILE)
1539 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1540 return rc;
1541}
1542
1543/* Convert a Linux signal to an access vector. */
1544static inline u32 signal_to_av(int sig)
1545{
1546 u32 perm = 0;
1547
1548 switch (sig) {
1549 case SIGCHLD:
1550 /* Commonly granted from child to parent. */
1551 perm = PROCESS__SIGCHLD;
1552 break;
1553 case SIGKILL:
1554 /* Cannot be caught or ignored */
1555 perm = PROCESS__SIGKILL;
1556 break;
1557 case SIGSTOP:
1558 /* Cannot be caught or ignored */
1559 perm = PROCESS__SIGSTOP;
1560 break;
1561 default:
1562 /* All other signals. */
1563 perm = PROCESS__SIGNAL;
1564 break;
1565 }
1566
1567 return perm;
1568}
1569
1570/*
1571 * Check permission between a pair of credentials
1572 * fork check, ptrace check, etc.
1573 */
1574static int cred_has_perm(const struct cred *actor,
1575 const struct cred *target,
1576 u32 perms)
1577{
1578 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1579
1580 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1581}
1582
1583/*
1584 * Check permission between a pair of tasks, e.g. signal checks,
1585 * fork check, ptrace check, etc.
1586 * tsk1 is the actor and tsk2 is the target
1587 * - this uses the default subjective creds of tsk1
1588 */
1589static int task_has_perm(const struct task_struct *tsk1,
1590 const struct task_struct *tsk2,
1591 u32 perms)
1592{
1593 const struct task_security_struct *__tsec1, *__tsec2;
1594 u32 sid1, sid2;
1595
1596 rcu_read_lock();
1597 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1598 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1599 rcu_read_unlock();
1600 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1601}
1602
1603/*
1604 * Check permission between current and another task, e.g. signal checks,
1605 * fork check, ptrace check, etc.
1606 * current is the actor and tsk2 is the target
1607 * - this uses current's subjective creds
1608 */
1609static int current_has_perm(const struct task_struct *tsk,
1610 u32 perms)
1611{
1612 u32 sid, tsid;
1613
1614 sid = current_sid();
1615 tsid = task_sid(tsk);
1616 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1617}
1618
1619#if CAP_LAST_CAP > 63
1620#error Fix SELinux to handle capabilities > 63.
1621#endif
1622
1623/* Check whether a task is allowed to use a capability. */
1624static int cred_has_capability(const struct cred *cred,
1625 int cap, int audit)
1626{
1627 struct common_audit_data ad;
1628 struct av_decision avd;
1629 u16 sclass;
1630 u32 sid = cred_sid(cred);
1631 u32 av = CAP_TO_MASK(cap);
1632 int rc;
1633
1634 ad.type = LSM_AUDIT_DATA_CAP;
1635 ad.u.cap = cap;
1636
1637 switch (CAP_TO_INDEX(cap)) {
1638 case 0:
1639 sclass = SECCLASS_CAPABILITY;
1640 break;
1641 case 1:
1642 sclass = SECCLASS_CAPABILITY2;
1643 break;
1644 default:
1645 printk(KERN_ERR
1646 "SELinux: out of range capability %d\n", cap);
1647 BUG();
1648 return -EINVAL;
1649 }
1650
1651 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1652 if (audit == SECURITY_CAP_AUDIT) {
1653 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1654 if (rc2)
1655 return rc2;
1656 }
1657 return rc;
1658}
1659
1660/* Check whether a task is allowed to use a system operation. */
1661static int task_has_system(struct task_struct *tsk,
1662 u32 perms)
1663{
1664 u32 sid = task_sid(tsk);
1665
1666 return avc_has_perm(sid, SECINITSID_KERNEL,
1667 SECCLASS_SYSTEM, perms, NULL);
1668}
1669
1670/* Check whether a task has a particular permission to an inode.
1671 The 'adp' parameter is optional and allows other audit
1672 data to be passed (e.g. the dentry). */
1673static int inode_has_perm(const struct cred *cred,
1674 struct inode *inode,
1675 u32 perms,
1676 struct common_audit_data *adp)
1677{
1678 struct inode_security_struct *isec;
1679 u32 sid;
1680
1681 validate_creds(cred);
1682
1683 if (unlikely(IS_PRIVATE(inode)))
1684 return 0;
1685
1686 sid = cred_sid(cred);
1687 isec = inode->i_security;
1688
1689 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1690}
1691
1692/* Same as inode_has_perm, but pass explicit audit data containing
1693 the dentry to help the auditing code to more easily generate the
1694 pathname if needed. */
1695static inline int dentry_has_perm(const struct cred *cred,
1696 struct dentry *dentry,
1697 u32 av)
1698{
1699 struct inode *inode = d_backing_inode(dentry);
1700 struct common_audit_data ad;
1701
1702 ad.type = LSM_AUDIT_DATA_DENTRY;
1703 ad.u.dentry = dentry;
1704 __inode_security_revalidate(inode, dentry, true);
1705 return inode_has_perm(cred, inode, av, &ad);
1706}
1707
1708/* Same as inode_has_perm, but pass explicit audit data containing
1709 the path to help the auditing code to more easily generate the
1710 pathname if needed. */
1711static inline int path_has_perm(const struct cred *cred,
1712 const struct path *path,
1713 u32 av)
1714{
1715 struct inode *inode = d_backing_inode(path->dentry);
1716 struct common_audit_data ad;
1717
1718 ad.type = LSM_AUDIT_DATA_PATH;
1719 ad.u.path = *path;
1720 __inode_security_revalidate(inode, path->dentry, true);
1721 return inode_has_perm(cred, inode, av, &ad);
1722}
1723
1724/* Same as path_has_perm, but uses the inode from the file struct. */
1725static inline int file_path_has_perm(const struct cred *cred,
1726 struct file *file,
1727 u32 av)
1728{
1729 struct common_audit_data ad;
1730
1731 ad.type = LSM_AUDIT_DATA_PATH;
1732 ad.u.path = file->f_path;
1733 return inode_has_perm(cred, file_inode(file), av, &ad);
1734}
1735
1736/* Check whether a task can use an open file descriptor to
1737 access an inode in a given way. Check access to the
1738 descriptor itself, and then use dentry_has_perm to
1739 check a particular permission to the file.
1740 Access to the descriptor is implicitly granted if it
1741 has the same SID as the process. If av is zero, then
1742 access to the file is not checked, e.g. for cases
1743 where only the descriptor is affected like seek. */
1744static int file_has_perm(const struct cred *cred,
1745 struct file *file,
1746 u32 av)
1747{
1748 struct file_security_struct *fsec = file->f_security;
1749 struct inode *inode = file_inode(file);
1750 struct common_audit_data ad;
1751 u32 sid = cred_sid(cred);
1752 int rc;
1753
1754 ad.type = LSM_AUDIT_DATA_PATH;
1755 ad.u.path = file->f_path;
1756
1757 if (sid != fsec->sid) {
1758 rc = avc_has_perm(sid, fsec->sid,
1759 SECCLASS_FD,
1760 FD__USE,
1761 &ad);
1762 if (rc)
1763 goto out;
1764 }
1765
1766 /* av is zero if only checking access to the descriptor. */
1767 rc = 0;
1768 if (av)
1769 rc = inode_has_perm(cred, inode, av, &ad);
1770
1771out:
1772 return rc;
1773}
1774
1775/*
1776 * Determine the label for an inode that might be unioned.
1777 */
1778static int selinux_determine_inode_label(struct inode *dir,
1779 const struct qstr *name,
1780 u16 tclass,
1781 u32 *_new_isid)
1782{
1783 const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1784 const struct inode_security_struct *dsec = inode_security(dir);
1785 const struct task_security_struct *tsec = current_security();
1786
1787 if ((sbsec->flags & SE_SBINITIALIZED) &&
1788 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1789 *_new_isid = sbsec->mntpoint_sid;
1790 } else if ((sbsec->flags & SBLABEL_MNT) &&
1791 tsec->create_sid) {
1792 *_new_isid = tsec->create_sid;
1793 } else {
1794 return security_transition_sid(tsec->sid, dsec->sid, tclass,
1795 name, _new_isid);
1796 }
1797
1798 return 0;
1799}
1800
1801/* Check whether a task can create a file. */
1802static int may_create(struct inode *dir,
1803 struct dentry *dentry,
1804 u16 tclass)
1805{
1806 const struct task_security_struct *tsec = current_security();
1807 struct inode_security_struct *dsec;
1808 struct superblock_security_struct *sbsec;
1809 u32 sid, newsid;
1810 struct common_audit_data ad;
1811 int rc;
1812
1813 dsec = inode_security(dir);
1814 sbsec = dir->i_sb->s_security;
1815
1816 sid = tsec->sid;
1817
1818 ad.type = LSM_AUDIT_DATA_DENTRY;
1819 ad.u.dentry = dentry;
1820
1821 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1822 DIR__ADD_NAME | DIR__SEARCH,
1823 &ad);
1824 if (rc)
1825 return rc;
1826
1827 rc = selinux_determine_inode_label(dir, &dentry->d_name, tclass,
1828 &newsid);
1829 if (rc)
1830 return rc;
1831
1832 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1833 if (rc)
1834 return rc;
1835
1836 return avc_has_perm(newsid, sbsec->sid,
1837 SECCLASS_FILESYSTEM,
1838 FILESYSTEM__ASSOCIATE, &ad);
1839}
1840
1841/* Check whether a task can create a key. */
1842static int may_create_key(u32 ksid,
1843 struct task_struct *ctx)
1844{
1845 u32 sid = task_sid(ctx);
1846
1847 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1848}
1849
1850#define MAY_LINK 0
1851#define MAY_UNLINK 1
1852#define MAY_RMDIR 2
1853
1854/* Check whether a task can link, unlink, or rmdir a file/directory. */
1855static int may_link(struct inode *dir,
1856 struct dentry *dentry,
1857 int kind)
1858
1859{
1860 struct inode_security_struct *dsec, *isec;
1861 struct common_audit_data ad;
1862 u32 sid = current_sid();
1863 u32 av;
1864 int rc;
1865
1866 dsec = inode_security(dir);
1867 isec = backing_inode_security(dentry);
1868
1869 ad.type = LSM_AUDIT_DATA_DENTRY;
1870 ad.u.dentry = dentry;
1871
1872 av = DIR__SEARCH;
1873 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1874 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1875 if (rc)
1876 return rc;
1877
1878 switch (kind) {
1879 case MAY_LINK:
1880 av = FILE__LINK;
1881 break;
1882 case MAY_UNLINK:
1883 av = FILE__UNLINK;
1884 break;
1885 case MAY_RMDIR:
1886 av = DIR__RMDIR;
1887 break;
1888 default:
1889 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1890 __func__, kind);
1891 return 0;
1892 }
1893
1894 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1895 return rc;
1896}
1897
1898static inline int may_rename(struct inode *old_dir,
1899 struct dentry *old_dentry,
1900 struct inode *new_dir,
1901 struct dentry *new_dentry)
1902{
1903 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1904 struct common_audit_data ad;
1905 u32 sid = current_sid();
1906 u32 av;
1907 int old_is_dir, new_is_dir;
1908 int rc;
1909
1910 old_dsec = inode_security(old_dir);
1911 old_isec = backing_inode_security(old_dentry);
1912 old_is_dir = d_is_dir(old_dentry);
1913 new_dsec = inode_security(new_dir);
1914
1915 ad.type = LSM_AUDIT_DATA_DENTRY;
1916
1917 ad.u.dentry = old_dentry;
1918 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1919 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1920 if (rc)
1921 return rc;
1922 rc = avc_has_perm(sid, old_isec->sid,
1923 old_isec->sclass, FILE__RENAME, &ad);
1924 if (rc)
1925 return rc;
1926 if (old_is_dir && new_dir != old_dir) {
1927 rc = avc_has_perm(sid, old_isec->sid,
1928 old_isec->sclass, DIR__REPARENT, &ad);
1929 if (rc)
1930 return rc;
1931 }
1932
1933 ad.u.dentry = new_dentry;
1934 av = DIR__ADD_NAME | DIR__SEARCH;
1935 if (d_is_positive(new_dentry))
1936 av |= DIR__REMOVE_NAME;
1937 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1938 if (rc)
1939 return rc;
1940 if (d_is_positive(new_dentry)) {
1941 new_isec = backing_inode_security(new_dentry);
1942 new_is_dir = d_is_dir(new_dentry);
1943 rc = avc_has_perm(sid, new_isec->sid,
1944 new_isec->sclass,
1945 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1946 if (rc)
1947 return rc;
1948 }
1949
1950 return 0;
1951}
1952
1953/* Check whether a task can perform a filesystem operation. */
1954static int superblock_has_perm(const struct cred *cred,
1955 struct super_block *sb,
1956 u32 perms,
1957 struct common_audit_data *ad)
1958{
1959 struct superblock_security_struct *sbsec;
1960 u32 sid = cred_sid(cred);
1961
1962 sbsec = sb->s_security;
1963 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1964}
1965
1966/* Convert a Linux mode and permission mask to an access vector. */
1967static inline u32 file_mask_to_av(int mode, int mask)
1968{
1969 u32 av = 0;
1970
1971 if (!S_ISDIR(mode)) {
1972 if (mask & MAY_EXEC)
1973 av |= FILE__EXECUTE;
1974 if (mask & MAY_READ)
1975 av |= FILE__READ;
1976
1977 if (mask & MAY_APPEND)
1978 av |= FILE__APPEND;
1979 else if (mask & MAY_WRITE)
1980 av |= FILE__WRITE;
1981
1982 } else {
1983 if (mask & MAY_EXEC)
1984 av |= DIR__SEARCH;
1985 if (mask & MAY_WRITE)
1986 av |= DIR__WRITE;
1987 if (mask & MAY_READ)
1988 av |= DIR__READ;
1989 }
1990
1991 return av;
1992}
1993
1994/* Convert a Linux file to an access vector. */
1995static inline u32 file_to_av(struct file *file)
1996{
1997 u32 av = 0;
1998
1999 if (file->f_mode & FMODE_READ)
2000 av |= FILE__READ;
2001 if (file->f_mode & FMODE_WRITE) {
2002 if (file->f_flags & O_APPEND)
2003 av |= FILE__APPEND;
2004 else
2005 av |= FILE__WRITE;
2006 }
2007 if (!av) {
2008 /*
2009 * Special file opened with flags 3 for ioctl-only use.
2010 */
2011 av = FILE__IOCTL;
2012 }
2013
2014 return av;
2015}
2016
2017/*
2018 * Convert a file to an access vector and include the correct open
2019 * open permission.
2020 */
2021static inline u32 open_file_to_av(struct file *file)
2022{
2023 u32 av = file_to_av(file);
2024
2025 if (selinux_policycap_openperm)
2026 av |= FILE__OPEN;
2027
2028 return av;
2029}
2030
2031/* Hook functions begin here. */
2032
2033static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2034{
2035 u32 mysid = current_sid();
2036 u32 mgrsid = task_sid(mgr);
2037
2038 return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER,
2039 BINDER__SET_CONTEXT_MGR, NULL);
2040}
2041
2042static int selinux_binder_transaction(struct task_struct *from,
2043 struct task_struct *to)
2044{
2045 u32 mysid = current_sid();
2046 u32 fromsid = task_sid(from);
2047 u32 tosid = task_sid(to);
2048 int rc;
2049
2050 if (mysid != fromsid) {
2051 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2052 BINDER__IMPERSONATE, NULL);
2053 if (rc)
2054 return rc;
2055 }
2056
2057 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2058 NULL);
2059}
2060
2061static int selinux_binder_transfer_binder(struct task_struct *from,
2062 struct task_struct *to)
2063{
2064 u32 fromsid = task_sid(from);
2065 u32 tosid = task_sid(to);
2066
2067 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2068 NULL);
2069}
2070
2071static int selinux_binder_transfer_file(struct task_struct *from,
2072 struct task_struct *to,
2073 struct file *file)
2074{
2075 u32 sid = task_sid(to);
2076 struct file_security_struct *fsec = file->f_security;
2077 struct dentry *dentry = file->f_path.dentry;
2078 struct inode_security_struct *isec = backing_inode_security(dentry);
2079 struct common_audit_data ad;
2080 int rc;
2081
2082 ad.type = LSM_AUDIT_DATA_PATH;
2083 ad.u.path = file->f_path;
2084
2085 if (sid != fsec->sid) {
2086 rc = avc_has_perm(sid, fsec->sid,
2087 SECCLASS_FD,
2088 FD__USE,
2089 &ad);
2090 if (rc)
2091 return rc;
2092 }
2093
2094 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2095 return 0;
2096
2097 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2098 &ad);
2099}
2100
2101static int selinux_ptrace_access_check(struct task_struct *child,
2102 unsigned int mode)
2103{
2104 if (mode & PTRACE_MODE_READ) {
2105 u32 sid = current_sid();
2106 u32 csid = task_sid(child);
2107 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2108 }
2109
2110 return current_has_perm(child, PROCESS__PTRACE);
2111}
2112
2113static int selinux_ptrace_traceme(struct task_struct *parent)
2114{
2115 return task_has_perm(parent, current, PROCESS__PTRACE);
2116}
2117
2118static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2119 kernel_cap_t *inheritable, kernel_cap_t *permitted)
2120{
2121 return current_has_perm(target, PROCESS__GETCAP);
2122}
2123
2124static int selinux_capset(struct cred *new, const struct cred *old,
2125 const kernel_cap_t *effective,
2126 const kernel_cap_t *inheritable,
2127 const kernel_cap_t *permitted)
2128{
2129 return cred_has_perm(old, new, PROCESS__SETCAP);
2130}
2131
2132/*
2133 * (This comment used to live with the selinux_task_setuid hook,
2134 * which was removed).
2135 *
2136 * Since setuid only affects the current process, and since the SELinux
2137 * controls are not based on the Linux identity attributes, SELinux does not
2138 * need to control this operation. However, SELinux does control the use of
2139 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2140 */
2141
2142static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2143 int cap, int audit)
2144{
2145 return cred_has_capability(cred, cap, audit);
2146}
2147
2148static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2149{
2150 const struct cred *cred = current_cred();
2151 int rc = 0;
2152
2153 if (!sb)
2154 return 0;
2155
2156 switch (cmds) {
2157 case Q_SYNC:
2158 case Q_QUOTAON:
2159 case Q_QUOTAOFF:
2160 case Q_SETINFO:
2161 case Q_SETQUOTA:
2162 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2163 break;
2164 case Q_GETFMT:
2165 case Q_GETINFO:
2166 case Q_GETQUOTA:
2167 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2168 break;
2169 default:
2170 rc = 0; /* let the kernel handle invalid cmds */
2171 break;
2172 }
2173 return rc;
2174}
2175
2176static int selinux_quota_on(struct dentry *dentry)
2177{
2178 const struct cred *cred = current_cred();
2179
2180 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2181}
2182
2183static int selinux_syslog(int type)
2184{
2185 int rc;
2186
2187 switch (type) {
2188 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2189 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2190 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2191 break;
2192 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2193 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2194 /* Set level of messages printed to console */
2195 case SYSLOG_ACTION_CONSOLE_LEVEL:
2196 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2197 break;
2198 case SYSLOG_ACTION_CLOSE: /* Close log */
2199 case SYSLOG_ACTION_OPEN: /* Open log */
2200 case SYSLOG_ACTION_READ: /* Read from log */
2201 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
2202 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
2203 default:
2204 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2205 break;
2206 }
2207 return rc;
2208}
2209
2210/*
2211 * Check that a process has enough memory to allocate a new virtual
2212 * mapping. 0 means there is enough memory for the allocation to
2213 * succeed and -ENOMEM implies there is not.
2214 *
2215 * Do not audit the selinux permission check, as this is applied to all
2216 * processes that allocate mappings.
2217 */
2218static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2219{
2220 int rc, cap_sys_admin = 0;
2221
2222 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2223 SECURITY_CAP_NOAUDIT);
2224 if (rc == 0)
2225 cap_sys_admin = 1;
2226
2227 return cap_sys_admin;
2228}
2229
2230/* binprm security operations */
2231
2232static int check_nnp_nosuid(const struct linux_binprm *bprm,
2233 const struct task_security_struct *old_tsec,
2234 const struct task_security_struct *new_tsec)
2235{
2236 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2237 int nosuid = (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID);
2238 int rc;
2239
2240 if (!nnp && !nosuid)
2241 return 0; /* neither NNP nor nosuid */
2242
2243 if (new_tsec->sid == old_tsec->sid)
2244 return 0; /* No change in credentials */
2245
2246 /*
2247 * The only transitions we permit under NNP or nosuid
2248 * are transitions to bounded SIDs, i.e. SIDs that are
2249 * guaranteed to only be allowed a subset of the permissions
2250 * of the current SID.
2251 */
2252 rc = security_bounded_transition(old_tsec->sid, new_tsec->sid);
2253 if (rc) {
2254 /*
2255 * On failure, preserve the errno values for NNP vs nosuid.
2256 * NNP: Operation not permitted for caller.
2257 * nosuid: Permission denied to file.
2258 */
2259 if (nnp)
2260 return -EPERM;
2261 else
2262 return -EACCES;
2263 }
2264 return 0;
2265}
2266
2267static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2268{
2269 const struct task_security_struct *old_tsec;
2270 struct task_security_struct *new_tsec;
2271 struct inode_security_struct *isec;
2272 struct common_audit_data ad;
2273 struct inode *inode = file_inode(bprm->file);
2274 int rc;
2275
2276 /* SELinux context only depends on initial program or script and not
2277 * the script interpreter */
2278 if (bprm->cred_prepared)
2279 return 0;
2280
2281 old_tsec = current_security();
2282 new_tsec = bprm->cred->security;
2283 isec = inode_security(inode);
2284
2285 /* Default to the current task SID. */
2286 new_tsec->sid = old_tsec->sid;
2287 new_tsec->osid = old_tsec->sid;
2288
2289 /* Reset fs, key, and sock SIDs on execve. */
2290 new_tsec->create_sid = 0;
2291 new_tsec->keycreate_sid = 0;
2292 new_tsec->sockcreate_sid = 0;
2293
2294 if (old_tsec->exec_sid) {
2295 new_tsec->sid = old_tsec->exec_sid;
2296 /* Reset exec SID on execve. */
2297 new_tsec->exec_sid = 0;
2298
2299 /* Fail on NNP or nosuid if not an allowed transition. */
2300 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2301 if (rc)
2302 return rc;
2303 } else {
2304 /* Check for a default transition on this program. */
2305 rc = security_transition_sid(old_tsec->sid, isec->sid,
2306 SECCLASS_PROCESS, NULL,
2307 &new_tsec->sid);
2308 if (rc)
2309 return rc;
2310
2311 /*
2312 * Fallback to old SID on NNP or nosuid if not an allowed
2313 * transition.
2314 */
2315 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2316 if (rc)
2317 new_tsec->sid = old_tsec->sid;
2318 }
2319
2320 ad.type = LSM_AUDIT_DATA_PATH;
2321 ad.u.path = bprm->file->f_path;
2322
2323 if (new_tsec->sid == old_tsec->sid) {
2324 rc = avc_has_perm(old_tsec->sid, isec->sid,
2325 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2326 if (rc)
2327 return rc;
2328 } else {
2329 /* Check permissions for the transition. */
2330 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2331 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2332 if (rc)
2333 return rc;
2334
2335 rc = avc_has_perm(new_tsec->sid, isec->sid,
2336 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2337 if (rc)
2338 return rc;
2339
2340 /* Check for shared state */
2341 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2342 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2343 SECCLASS_PROCESS, PROCESS__SHARE,
2344 NULL);
2345 if (rc)
2346 return -EPERM;
2347 }
2348
2349 /* Make sure that anyone attempting to ptrace over a task that
2350 * changes its SID has the appropriate permit */
2351 if (bprm->unsafe &
2352 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2353 struct task_struct *tracer;
2354 struct task_security_struct *sec;
2355 u32 ptsid = 0;
2356
2357 rcu_read_lock();
2358 tracer = ptrace_parent(current);
2359 if (likely(tracer != NULL)) {
2360 sec = __task_cred(tracer)->security;
2361 ptsid = sec->sid;
2362 }
2363 rcu_read_unlock();
2364
2365 if (ptsid != 0) {
2366 rc = avc_has_perm(ptsid, new_tsec->sid,
2367 SECCLASS_PROCESS,
2368 PROCESS__PTRACE, NULL);
2369 if (rc)
2370 return -EPERM;
2371 }
2372 }
2373
2374 /* Clear any possibly unsafe personality bits on exec: */
2375 bprm->per_clear |= PER_CLEAR_ON_SETID;
2376 }
2377
2378 return 0;
2379}
2380
2381static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2382{
2383 const struct task_security_struct *tsec = current_security();
2384 u32 sid, osid;
2385 int atsecure = 0;
2386
2387 sid = tsec->sid;
2388 osid = tsec->osid;
2389
2390 if (osid != sid) {
2391 /* Enable secure mode for SIDs transitions unless
2392 the noatsecure permission is granted between
2393 the two SIDs, i.e. ahp returns 0. */
2394 atsecure = avc_has_perm(osid, sid,
2395 SECCLASS_PROCESS,
2396 PROCESS__NOATSECURE, NULL);
2397 }
2398
2399 return !!atsecure;
2400}
2401
2402static int match_file(const void *p, struct file *file, unsigned fd)
2403{
2404 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2405}
2406
2407/* Derived from fs/exec.c:flush_old_files. */
2408static inline void flush_unauthorized_files(const struct cred *cred,
2409 struct files_struct *files)
2410{
2411 struct file *file, *devnull = NULL;
2412 struct tty_struct *tty;
2413 int drop_tty = 0;
2414 unsigned n;
2415
2416 tty = get_current_tty();
2417 if (tty) {
2418 spin_lock(&tty->files_lock);
2419 if (!list_empty(&tty->tty_files)) {
2420 struct tty_file_private *file_priv;
2421
2422 /* Revalidate access to controlling tty.
2423 Use file_path_has_perm on the tty path directly
2424 rather than using file_has_perm, as this particular
2425 open file may belong to another process and we are
2426 only interested in the inode-based check here. */
2427 file_priv = list_first_entry(&tty->tty_files,
2428 struct tty_file_private, list);
2429 file = file_priv->file;
2430 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2431 drop_tty = 1;
2432 }
2433 spin_unlock(&tty->files_lock);
2434 tty_kref_put(tty);
2435 }
2436 /* Reset controlling tty. */
2437 if (drop_tty)
2438 no_tty();
2439
2440 /* Revalidate access to inherited open files. */
2441 n = iterate_fd(files, 0, match_file, cred);
2442 if (!n) /* none found? */
2443 return;
2444
2445 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2446 if (IS_ERR(devnull))
2447 devnull = NULL;
2448 /* replace all the matching ones with this */
2449 do {
2450 replace_fd(n - 1, devnull, 0);
2451 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2452 if (devnull)
2453 fput(devnull);
2454}
2455
2456/*
2457 * Prepare a process for imminent new credential changes due to exec
2458 */
2459static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2460{
2461 struct task_security_struct *new_tsec;
2462 struct rlimit *rlim, *initrlim;
2463 int rc, i;
2464
2465 new_tsec = bprm->cred->security;
2466 if (new_tsec->sid == new_tsec->osid)
2467 return;
2468
2469 /* Close files for which the new task SID is not authorized. */
2470 flush_unauthorized_files(bprm->cred, current->files);
2471
2472 /* Always clear parent death signal on SID transitions. */
2473 current->pdeath_signal = 0;
2474
2475 /* Check whether the new SID can inherit resource limits from the old
2476 * SID. If not, reset all soft limits to the lower of the current
2477 * task's hard limit and the init task's soft limit.
2478 *
2479 * Note that the setting of hard limits (even to lower them) can be
2480 * controlled by the setrlimit check. The inclusion of the init task's
2481 * soft limit into the computation is to avoid resetting soft limits
2482 * higher than the default soft limit for cases where the default is
2483 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2484 */
2485 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2486 PROCESS__RLIMITINH, NULL);
2487 if (rc) {
2488 /* protect against do_prlimit() */
2489 task_lock(current);
2490 for (i = 0; i < RLIM_NLIMITS; i++) {
2491 rlim = current->signal->rlim + i;
2492 initrlim = init_task.signal->rlim + i;
2493 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2494 }
2495 task_unlock(current);
2496 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2497 }
2498}
2499
2500/*
2501 * Clean up the process immediately after the installation of new credentials
2502 * due to exec
2503 */
2504static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2505{
2506 const struct task_security_struct *tsec = current_security();
2507 struct itimerval itimer;
2508 u32 osid, sid;
2509 int rc, i;
2510
2511 osid = tsec->osid;
2512 sid = tsec->sid;
2513
2514 if (sid == osid)
2515 return;
2516
2517 /* Check whether the new SID can inherit signal state from the old SID.
2518 * If not, clear itimers to avoid subsequent signal generation and
2519 * flush and unblock signals.
2520 *
2521 * This must occur _after_ the task SID has been updated so that any
2522 * kill done after the flush will be checked against the new SID.
2523 */
2524 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2525 if (rc) {
2526 memset(&itimer, 0, sizeof itimer);
2527 for (i = 0; i < 3; i++)
2528 do_setitimer(i, &itimer, NULL);
2529 spin_lock_irq(¤t->sighand->siglock);
2530 if (!fatal_signal_pending(current)) {
2531 flush_sigqueue(¤t->pending);
2532 flush_sigqueue(¤t->signal->shared_pending);
2533 flush_signal_handlers(current, 1);
2534 sigemptyset(¤t->blocked);
2535 recalc_sigpending();
2536 }
2537 spin_unlock_irq(¤t->sighand->siglock);
2538 }
2539
2540 /* Wake up the parent if it is waiting so that it can recheck
2541 * wait permission to the new task SID. */
2542 read_lock(&tasklist_lock);
2543 __wake_up_parent(current, current->real_parent);
2544 read_unlock(&tasklist_lock);
2545}
2546
2547/* superblock security operations */
2548
2549static int selinux_sb_alloc_security(struct super_block *sb)
2550{
2551 return superblock_alloc_security(sb);
2552}
2553
2554static void selinux_sb_free_security(struct super_block *sb)
2555{
2556 superblock_free_security(sb);
2557}
2558
2559static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2560{
2561 if (plen > olen)
2562 return 0;
2563
2564 return !memcmp(prefix, option, plen);
2565}
2566
2567static inline int selinux_option(char *option, int len)
2568{
2569 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2570 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2571 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2572 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2573 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2574}
2575
2576static inline void take_option(char **to, char *from, int *first, int len)
2577{
2578 if (!*first) {
2579 **to = ',';
2580 *to += 1;
2581 } else
2582 *first = 0;
2583 memcpy(*to, from, len);
2584 *to += len;
2585}
2586
2587static inline void take_selinux_option(char **to, char *from, int *first,
2588 int len)
2589{
2590 int current_size = 0;
2591
2592 if (!*first) {
2593 **to = '|';
2594 *to += 1;
2595 } else
2596 *first = 0;
2597
2598 while (current_size < len) {
2599 if (*from != '"') {
2600 **to = *from;
2601 *to += 1;
2602 }
2603 from += 1;
2604 current_size += 1;
2605 }
2606}
2607
2608static int selinux_sb_copy_data(char *orig, char *copy)
2609{
2610 int fnosec, fsec, rc = 0;
2611 char *in_save, *in_curr, *in_end;
2612 char *sec_curr, *nosec_save, *nosec;
2613 int open_quote = 0;
2614
2615 in_curr = orig;
2616 sec_curr = copy;
2617
2618 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2619 if (!nosec) {
2620 rc = -ENOMEM;
2621 goto out;
2622 }
2623
2624 nosec_save = nosec;
2625 fnosec = fsec = 1;
2626 in_save = in_end = orig;
2627
2628 do {
2629 if (*in_end == '"')
2630 open_quote = !open_quote;
2631 if ((*in_end == ',' && open_quote == 0) ||
2632 *in_end == '\0') {
2633 int len = in_end - in_curr;
2634
2635 if (selinux_option(in_curr, len))
2636 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2637 else
2638 take_option(&nosec, in_curr, &fnosec, len);
2639
2640 in_curr = in_end + 1;
2641 }
2642 } while (*in_end++);
2643
2644 strcpy(in_save, nosec_save);
2645 free_page((unsigned long)nosec_save);
2646out:
2647 return rc;
2648}
2649
2650static int selinux_sb_remount(struct super_block *sb, void *data)
2651{
2652 int rc, i, *flags;
2653 struct security_mnt_opts opts;
2654 char *secdata, **mount_options;
2655 struct superblock_security_struct *sbsec = sb->s_security;
2656
2657 if (!(sbsec->flags & SE_SBINITIALIZED))
2658 return 0;
2659
2660 if (!data)
2661 return 0;
2662
2663 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2664 return 0;
2665
2666 security_init_mnt_opts(&opts);
2667 secdata = alloc_secdata();
2668 if (!secdata)
2669 return -ENOMEM;
2670 rc = selinux_sb_copy_data(data, secdata);
2671 if (rc)
2672 goto out_free_secdata;
2673
2674 rc = selinux_parse_opts_str(secdata, &opts);
2675 if (rc)
2676 goto out_free_secdata;
2677
2678 mount_options = opts.mnt_opts;
2679 flags = opts.mnt_opts_flags;
2680
2681 for (i = 0; i < opts.num_mnt_opts; i++) {
2682 u32 sid;
2683
2684 if (flags[i] == SBLABEL_MNT)
2685 continue;
2686 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
2687 if (rc) {
2688 printk(KERN_WARNING "SELinux: security_context_str_to_sid"
2689 "(%s) failed for (dev %s, type %s) errno=%d\n",
2690 mount_options[i], sb->s_id, sb->s_type->name, rc);
2691 goto out_free_opts;
2692 }
2693 rc = -EINVAL;
2694 switch (flags[i]) {
2695 case FSCONTEXT_MNT:
2696 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2697 goto out_bad_option;
2698 break;
2699 case CONTEXT_MNT:
2700 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2701 goto out_bad_option;
2702 break;
2703 case ROOTCONTEXT_MNT: {
2704 struct inode_security_struct *root_isec;
2705 root_isec = backing_inode_security(sb->s_root);
2706
2707 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2708 goto out_bad_option;
2709 break;
2710 }
2711 case DEFCONTEXT_MNT:
2712 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2713 goto out_bad_option;
2714 break;
2715 default:
2716 goto out_free_opts;
2717 }
2718 }
2719
2720 rc = 0;
2721out_free_opts:
2722 security_free_mnt_opts(&opts);
2723out_free_secdata:
2724 free_secdata(secdata);
2725 return rc;
2726out_bad_option:
2727 printk(KERN_WARNING "SELinux: unable to change security options "
2728 "during remount (dev %s, type=%s)\n", sb->s_id,
2729 sb->s_type->name);
2730 goto out_free_opts;
2731}
2732
2733static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2734{
2735 const struct cred *cred = current_cred();
2736 struct common_audit_data ad;
2737 int rc;
2738
2739 rc = superblock_doinit(sb, data);
2740 if (rc)
2741 return rc;
2742
2743 /* Allow all mounts performed by the kernel */
2744 if (flags & MS_KERNMOUNT)
2745 return 0;
2746
2747 ad.type = LSM_AUDIT_DATA_DENTRY;
2748 ad.u.dentry = sb->s_root;
2749 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2750}
2751
2752static int selinux_sb_statfs(struct dentry *dentry)
2753{
2754 const struct cred *cred = current_cred();
2755 struct common_audit_data ad;
2756
2757 ad.type = LSM_AUDIT_DATA_DENTRY;
2758 ad.u.dentry = dentry->d_sb->s_root;
2759 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2760}
2761
2762static int selinux_mount(const char *dev_name,
2763 struct path *path,
2764 const char *type,
2765 unsigned long flags,
2766 void *data)
2767{
2768 const struct cred *cred = current_cred();
2769
2770 if (flags & MS_REMOUNT)
2771 return superblock_has_perm(cred, path->dentry->d_sb,
2772 FILESYSTEM__REMOUNT, NULL);
2773 else
2774 return path_has_perm(cred, path, FILE__MOUNTON);
2775}
2776
2777static int selinux_umount(struct vfsmount *mnt, int flags)
2778{
2779 const struct cred *cred = current_cred();
2780
2781 return superblock_has_perm(cred, mnt->mnt_sb,
2782 FILESYSTEM__UNMOUNT, NULL);
2783}
2784
2785/* inode security operations */
2786
2787static int selinux_inode_alloc_security(struct inode *inode)
2788{
2789 return inode_alloc_security(inode);
2790}
2791
2792static void selinux_inode_free_security(struct inode *inode)
2793{
2794 inode_free_security(inode);
2795}
2796
2797static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2798 struct qstr *name, void **ctx,
2799 u32 *ctxlen)
2800{
2801 u32 newsid;
2802 int rc;
2803
2804 rc = selinux_determine_inode_label(d_inode(dentry->d_parent), name,
2805 inode_mode_to_security_class(mode),
2806 &newsid);
2807 if (rc)
2808 return rc;
2809
2810 return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2811}
2812
2813static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2814 const struct qstr *qstr,
2815 const char **name,
2816 void **value, size_t *len)
2817{
2818 const struct task_security_struct *tsec = current_security();
2819 struct superblock_security_struct *sbsec;
2820 u32 sid, newsid, clen;
2821 int rc;
2822 char *context;
2823
2824 sbsec = dir->i_sb->s_security;
2825
2826 sid = tsec->sid;
2827 newsid = tsec->create_sid;
2828
2829 rc = selinux_determine_inode_label(
2830 dir, qstr,
2831 inode_mode_to_security_class(inode->i_mode),
2832 &newsid);
2833 if (rc)
2834 return rc;
2835
2836 /* Possibly defer initialization to selinux_complete_init. */
2837 if (sbsec->flags & SE_SBINITIALIZED) {
2838 struct inode_security_struct *isec = inode->i_security;
2839 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2840 isec->sid = newsid;
2841 isec->initialized = LABEL_INITIALIZED;
2842 }
2843
2844 if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2845 return -EOPNOTSUPP;
2846
2847 if (name)
2848 *name = XATTR_SELINUX_SUFFIX;
2849
2850 if (value && len) {
2851 rc = security_sid_to_context_force(newsid, &context, &clen);
2852 if (rc)
2853 return rc;
2854 *value = context;
2855 *len = clen;
2856 }
2857
2858 return 0;
2859}
2860
2861static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2862{
2863 return may_create(dir, dentry, SECCLASS_FILE);
2864}
2865
2866static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2867{
2868 return may_link(dir, old_dentry, MAY_LINK);
2869}
2870
2871static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2872{
2873 return may_link(dir, dentry, MAY_UNLINK);
2874}
2875
2876static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2877{
2878 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2879}
2880
2881static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2882{
2883 return may_create(dir, dentry, SECCLASS_DIR);
2884}
2885
2886static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2887{
2888 return may_link(dir, dentry, MAY_RMDIR);
2889}
2890
2891static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2892{
2893 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2894}
2895
2896static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2897 struct inode *new_inode, struct dentry *new_dentry)
2898{
2899 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2900}
2901
2902static int selinux_inode_readlink(struct dentry *dentry)
2903{
2904 const struct cred *cred = current_cred();
2905
2906 return dentry_has_perm(cred, dentry, FILE__READ);
2907}
2908
2909static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2910 bool rcu)
2911{
2912 const struct cred *cred = current_cred();
2913 struct common_audit_data ad;
2914 struct inode_security_struct *isec;
2915 u32 sid;
2916
2917 validate_creds(cred);
2918
2919 ad.type = LSM_AUDIT_DATA_DENTRY;
2920 ad.u.dentry = dentry;
2921 sid = cred_sid(cred);
2922 isec = inode_security_rcu(inode, rcu);
2923 if (IS_ERR(isec))
2924 return PTR_ERR(isec);
2925
2926 return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad,
2927 rcu ? MAY_NOT_BLOCK : 0);
2928}
2929
2930static noinline int audit_inode_permission(struct inode *inode,
2931 u32 perms, u32 audited, u32 denied,
2932 int result,
2933 unsigned flags)
2934{
2935 struct common_audit_data ad;
2936 struct inode_security_struct *isec = inode->i_security;
2937 int rc;
2938
2939 ad.type = LSM_AUDIT_DATA_INODE;
2940 ad.u.inode = inode;
2941
2942 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2943 audited, denied, result, &ad, flags);
2944 if (rc)
2945 return rc;
2946 return 0;
2947}
2948
2949static int selinux_inode_permission(struct inode *inode, int mask)
2950{
2951 const struct cred *cred = current_cred();
2952 u32 perms;
2953 bool from_access;
2954 unsigned flags = mask & MAY_NOT_BLOCK;
2955 struct inode_security_struct *isec;
2956 u32 sid;
2957 struct av_decision avd;
2958 int rc, rc2;
2959 u32 audited, denied;
2960
2961 from_access = mask & MAY_ACCESS;
2962 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2963
2964 /* No permission to check. Existence test. */
2965 if (!mask)
2966 return 0;
2967
2968 validate_creds(cred);
2969
2970 if (unlikely(IS_PRIVATE(inode)))
2971 return 0;
2972
2973 perms = file_mask_to_av(inode->i_mode, mask);
2974
2975 sid = cred_sid(cred);
2976 isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
2977 if (IS_ERR(isec))
2978 return PTR_ERR(isec);
2979
2980 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2981 audited = avc_audit_required(perms, &avd, rc,
2982 from_access ? FILE__AUDIT_ACCESS : 0,
2983 &denied);
2984 if (likely(!audited))
2985 return rc;
2986
2987 rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
2988 if (rc2)
2989 return rc2;
2990 return rc;
2991}
2992
2993static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2994{
2995 const struct cred *cred = current_cred();
2996 unsigned int ia_valid = iattr->ia_valid;
2997 __u32 av = FILE__WRITE;
2998
2999 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3000 if (ia_valid & ATTR_FORCE) {
3001 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3002 ATTR_FORCE);
3003 if (!ia_valid)
3004 return 0;
3005 }
3006
3007 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3008 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3009 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3010
3011 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE)
3012 && !(ia_valid & ATTR_FILE))
3013 av |= FILE__OPEN;
3014
3015 return dentry_has_perm(cred, dentry, av);
3016}
3017
3018static int selinux_inode_getattr(const struct path *path)
3019{
3020 return path_has_perm(current_cred(), path, FILE__GETATTR);
3021}
3022
3023static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
3024{
3025 const struct cred *cred = current_cred();
3026
3027 if (!strncmp(name, XATTR_SECURITY_PREFIX,
3028 sizeof XATTR_SECURITY_PREFIX - 1)) {
3029 if (!strcmp(name, XATTR_NAME_CAPS)) {
3030 if (!capable(CAP_SETFCAP))
3031 return -EPERM;
3032 } else if (!capable(CAP_SYS_ADMIN)) {
3033 /* A different attribute in the security namespace.
3034 Restrict to administrator. */
3035 return -EPERM;
3036 }
3037 }
3038
3039 /* Not an attribute we recognize, so just check the
3040 ordinary setattr permission. */
3041 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3042}
3043
3044static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3045 const void *value, size_t size, int flags)
3046{
3047 struct inode *inode = d_backing_inode(dentry);
3048 struct inode_security_struct *isec = backing_inode_security(dentry);
3049 struct superblock_security_struct *sbsec;
3050 struct common_audit_data ad;
3051 u32 newsid, sid = current_sid();
3052 int rc = 0;
3053
3054 if (strcmp(name, XATTR_NAME_SELINUX))
3055 return selinux_inode_setotherxattr(dentry, name);
3056
3057 sbsec = inode->i_sb->s_security;
3058 if (!(sbsec->flags & SBLABEL_MNT))
3059 return -EOPNOTSUPP;
3060
3061 if (!inode_owner_or_capable(inode))
3062 return -EPERM;
3063
3064 ad.type = LSM_AUDIT_DATA_DENTRY;
3065 ad.u.dentry = dentry;
3066
3067 rc = avc_has_perm(sid, isec->sid, isec->sclass,
3068 FILE__RELABELFROM, &ad);
3069 if (rc)
3070 return rc;
3071
3072 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3073 if (rc == -EINVAL) {
3074 if (!capable(CAP_MAC_ADMIN)) {
3075 struct audit_buffer *ab;
3076 size_t audit_size;
3077 const char *str;
3078
3079 /* We strip a nul only if it is at the end, otherwise the
3080 * context contains a nul and we should audit that */
3081 if (value) {
3082 str = value;
3083 if (str[size - 1] == '\0')
3084 audit_size = size - 1;
3085 else
3086 audit_size = size;
3087 } else {
3088 str = "";
3089 audit_size = 0;
3090 }
3091 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
3092 audit_log_format(ab, "op=setxattr invalid_context=");
3093 audit_log_n_untrustedstring(ab, value, audit_size);
3094 audit_log_end(ab);
3095
3096 return rc;
3097 }
3098 rc = security_context_to_sid_force(value, size, &newsid);
3099 }
3100 if (rc)
3101 return rc;
3102
3103 rc = avc_has_perm(sid, newsid, isec->sclass,
3104 FILE__RELABELTO, &ad);
3105 if (rc)
3106 return rc;
3107
3108 rc = security_validate_transition(isec->sid, newsid, sid,
3109 isec->sclass);
3110 if (rc)
3111 return rc;
3112
3113 return avc_has_perm(newsid,
3114 sbsec->sid,
3115 SECCLASS_FILESYSTEM,
3116 FILESYSTEM__ASSOCIATE,
3117 &ad);
3118}
3119
3120static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3121 const void *value, size_t size,
3122 int flags)
3123{
3124 struct inode *inode = d_backing_inode(dentry);
3125 struct inode_security_struct *isec = backing_inode_security(dentry);
3126 u32 newsid;
3127 int rc;
3128
3129 if (strcmp(name, XATTR_NAME_SELINUX)) {
3130 /* Not an attribute we recognize, so nothing to do. */
3131 return;
3132 }
3133
3134 rc = security_context_to_sid_force(value, size, &newsid);
3135 if (rc) {
3136 printk(KERN_ERR "SELinux: unable to map context to SID"
3137 "for (%s, %lu), rc=%d\n",
3138 inode->i_sb->s_id, inode->i_ino, -rc);
3139 return;
3140 }
3141
3142 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3143 isec->sid = newsid;
3144 isec->initialized = LABEL_INITIALIZED;
3145
3146 return;
3147}
3148
3149static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3150{
3151 const struct cred *cred = current_cred();
3152
3153 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3154}
3155
3156static int selinux_inode_listxattr(struct dentry *dentry)
3157{
3158 const struct cred *cred = current_cred();
3159
3160 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3161}
3162
3163static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3164{
3165 if (strcmp(name, XATTR_NAME_SELINUX))
3166 return selinux_inode_setotherxattr(dentry, name);
3167
3168 /* No one is allowed to remove a SELinux security label.
3169 You can change the label, but all data must be labeled. */
3170 return -EACCES;
3171}
3172
3173/*
3174 * Copy the inode security context value to the user.
3175 *
3176 * Permission check is handled by selinux_inode_getxattr hook.
3177 */
3178static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3179{
3180 u32 size;
3181 int error;
3182 char *context = NULL;
3183 struct inode_security_struct *isec = inode_security(inode);
3184
3185 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3186 return -EOPNOTSUPP;
3187
3188 /*
3189 * If the caller has CAP_MAC_ADMIN, then get the raw context
3190 * value even if it is not defined by current policy; otherwise,
3191 * use the in-core value under current policy.
3192 * Use the non-auditing forms of the permission checks since
3193 * getxattr may be called by unprivileged processes commonly
3194 * and lack of permission just means that we fall back to the
3195 * in-core context value, not a denial.
3196 */
3197 error = cap_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3198 SECURITY_CAP_NOAUDIT);
3199 if (!error)
3200 error = cred_has_capability(current_cred(), CAP_MAC_ADMIN,
3201 SECURITY_CAP_NOAUDIT);
3202 if (!error)
3203 error = security_sid_to_context_force(isec->sid, &context,
3204 &size);
3205 else
3206 error = security_sid_to_context(isec->sid, &context, &size);
3207 if (error)
3208 return error;
3209 error = size;
3210 if (alloc) {
3211 *buffer = context;
3212 goto out_nofree;
3213 }
3214 kfree(context);
3215out_nofree:
3216 return error;
3217}
3218
3219static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3220 const void *value, size_t size, int flags)
3221{
3222 struct inode_security_struct *isec = inode_security(inode);
3223 u32 newsid;
3224 int rc;
3225
3226 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3227 return -EOPNOTSUPP;
3228
3229 if (!value || !size)
3230 return -EACCES;
3231
3232 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3233 if (rc)
3234 return rc;
3235
3236 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3237 isec->sid = newsid;
3238 isec->initialized = LABEL_INITIALIZED;
3239 return 0;
3240}
3241
3242static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3243{
3244 const int len = sizeof(XATTR_NAME_SELINUX);
3245 if (buffer && len <= buffer_size)
3246 memcpy(buffer, XATTR_NAME_SELINUX, len);
3247 return len;
3248}
3249
3250static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3251{
3252 struct inode_security_struct *isec = inode_security_novalidate(inode);
3253 *secid = isec->sid;
3254}
3255
3256/* file security operations */
3257
3258static int selinux_revalidate_file_permission(struct file *file, int mask)
3259{
3260 const struct cred *cred = current_cred();
3261 struct inode *inode = file_inode(file);
3262
3263 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3264 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3265 mask |= MAY_APPEND;
3266
3267 return file_has_perm(cred, file,
3268 file_mask_to_av(inode->i_mode, mask));
3269}
3270
3271static int selinux_file_permission(struct file *file, int mask)
3272{
3273 struct inode *inode = file_inode(file);
3274 struct file_security_struct *fsec = file->f_security;
3275 struct inode_security_struct *isec;
3276 u32 sid = current_sid();
3277
3278 if (!mask)
3279 /* No permission to check. Existence test. */
3280 return 0;
3281
3282 isec = inode_security(inode);
3283 if (sid == fsec->sid && fsec->isid == isec->sid &&
3284 fsec->pseqno == avc_policy_seqno())
3285 /* No change since file_open check. */
3286 return 0;
3287
3288 return selinux_revalidate_file_permission(file, mask);
3289}
3290
3291static int selinux_file_alloc_security(struct file *file)
3292{
3293 return file_alloc_security(file);
3294}
3295
3296static void selinux_file_free_security(struct file *file)
3297{
3298 file_free_security(file);
3299}
3300
3301/*
3302 * Check whether a task has the ioctl permission and cmd
3303 * operation to an inode.
3304 */
3305static int ioctl_has_perm(const struct cred *cred, struct file *file,
3306 u32 requested, u16 cmd)
3307{
3308 struct common_audit_data ad;
3309 struct file_security_struct *fsec = file->f_security;
3310 struct inode *inode = file_inode(file);
3311 struct inode_security_struct *isec = inode_security(inode);
3312 struct lsm_ioctlop_audit ioctl;
3313 u32 ssid = cred_sid(cred);
3314 int rc;
3315 u8 driver = cmd >> 8;
3316 u8 xperm = cmd & 0xff;
3317
3318 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3319 ad.u.op = &ioctl;
3320 ad.u.op->cmd = cmd;
3321 ad.u.op->path = file->f_path;
3322
3323 if (ssid != fsec->sid) {
3324 rc = avc_has_perm(ssid, fsec->sid,
3325 SECCLASS_FD,
3326 FD__USE,
3327 &ad);
3328 if (rc)
3329 goto out;
3330 }
3331
3332 if (unlikely(IS_PRIVATE(inode)))
3333 return 0;
3334
3335 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
3336 requested, driver, xperm, &ad);
3337out:
3338 return rc;
3339}
3340
3341static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3342 unsigned long arg)
3343{
3344 const struct cred *cred = current_cred();
3345 int error = 0;
3346
3347 switch (cmd) {
3348 case FIONREAD:
3349 /* fall through */
3350 case FIBMAP:
3351 /* fall through */
3352 case FIGETBSZ:
3353 /* fall through */
3354 case FS_IOC_GETFLAGS:
3355 /* fall through */
3356 case FS_IOC_GETVERSION:
3357 error = file_has_perm(cred, file, FILE__GETATTR);
3358 break;
3359
3360 case FS_IOC_SETFLAGS:
3361 /* fall through */
3362 case FS_IOC_SETVERSION:
3363 error = file_has_perm(cred, file, FILE__SETATTR);
3364 break;
3365
3366 /* sys_ioctl() checks */
3367 case FIONBIO:
3368 /* fall through */
3369 case FIOASYNC:
3370 error = file_has_perm(cred, file, 0);
3371 break;
3372
3373 case KDSKBENT:
3374 case KDSKBSENT:
3375 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3376 SECURITY_CAP_AUDIT);
3377 break;
3378
3379 /* default case assumes that the command will go
3380 * to the file's ioctl() function.
3381 */
3382 default:
3383 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3384 }
3385 return error;
3386}
3387
3388static int default_noexec;
3389
3390static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3391{
3392 const struct cred *cred = current_cred();
3393 int rc = 0;
3394
3395 if (default_noexec &&
3396 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3397 (!shared && (prot & PROT_WRITE)))) {
3398 /*
3399 * We are making executable an anonymous mapping or a
3400 * private file mapping that will also be writable.
3401 * This has an additional check.
3402 */
3403 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3404 if (rc)
3405 goto error;
3406 }
3407
3408 if (file) {
3409 /* read access is always possible with a mapping */
3410 u32 av = FILE__READ;
3411
3412 /* write access only matters if the mapping is shared */
3413 if (shared && (prot & PROT_WRITE))
3414 av |= FILE__WRITE;
3415
3416 if (prot & PROT_EXEC)
3417 av |= FILE__EXECUTE;
3418
3419 return file_has_perm(cred, file, av);
3420 }
3421
3422error:
3423 return rc;
3424}
3425
3426static int selinux_mmap_addr(unsigned long addr)
3427{
3428 int rc = 0;
3429
3430 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3431 u32 sid = current_sid();
3432 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3433 MEMPROTECT__MMAP_ZERO, NULL);
3434 }
3435
3436 return rc;
3437}
3438
3439static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3440 unsigned long prot, unsigned long flags)
3441{
3442 if (selinux_checkreqprot)
3443 prot = reqprot;
3444
3445 return file_map_prot_check(file, prot,
3446 (flags & MAP_TYPE) == MAP_SHARED);
3447}
3448
3449static int selinux_file_mprotect(struct vm_area_struct *vma,
3450 unsigned long reqprot,
3451 unsigned long prot)
3452{
3453 const struct cred *cred = current_cred();
3454
3455 if (selinux_checkreqprot)
3456 prot = reqprot;
3457
3458 if (default_noexec &&
3459 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3460 int rc = 0;
3461 if (vma->vm_start >= vma->vm_mm->start_brk &&
3462 vma->vm_end <= vma->vm_mm->brk) {
3463 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3464 } else if (!vma->vm_file &&
3465 vma->vm_start <= vma->vm_mm->start_stack &&
3466 vma->vm_end >= vma->vm_mm->start_stack) {
3467 rc = current_has_perm(current, PROCESS__EXECSTACK);
3468 } else if (vma->vm_file && vma->anon_vma) {
3469 /*
3470 * We are making executable a file mapping that has
3471 * had some COW done. Since pages might have been
3472 * written, check ability to execute the possibly
3473 * modified content. This typically should only
3474 * occur for text relocations.
3475 */
3476 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3477 }
3478 if (rc)
3479 return rc;
3480 }
3481
3482 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3483}
3484
3485static int selinux_file_lock(struct file *file, unsigned int cmd)
3486{
3487 const struct cred *cred = current_cred();
3488
3489 return file_has_perm(cred, file, FILE__LOCK);
3490}
3491
3492static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3493 unsigned long arg)
3494{
3495 const struct cred *cred = current_cred();
3496 int err = 0;
3497
3498 switch (cmd) {
3499 case F_SETFL:
3500 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3501 err = file_has_perm(cred, file, FILE__WRITE);
3502 break;
3503 }
3504 /* fall through */
3505 case F_SETOWN:
3506 case F_SETSIG:
3507 case F_GETFL:
3508 case F_GETOWN:
3509 case F_GETSIG:
3510 case F_GETOWNER_UIDS:
3511 /* Just check FD__USE permission */
3512 err = file_has_perm(cred, file, 0);
3513 break;
3514 case F_GETLK:
3515 case F_SETLK:
3516 case F_SETLKW:
3517 case F_OFD_GETLK:
3518 case F_OFD_SETLK:
3519 case F_OFD_SETLKW:
3520#if BITS_PER_LONG == 32
3521 case F_GETLK64:
3522 case F_SETLK64:
3523 case F_SETLKW64:
3524#endif
3525 err = file_has_perm(cred, file, FILE__LOCK);
3526 break;
3527 }
3528
3529 return err;
3530}
3531
3532static void selinux_file_set_fowner(struct file *file)
3533{
3534 struct file_security_struct *fsec;
3535
3536 fsec = file->f_security;
3537 fsec->fown_sid = current_sid();
3538}
3539
3540static int selinux_file_send_sigiotask(struct task_struct *tsk,
3541 struct fown_struct *fown, int signum)
3542{
3543 struct file *file;
3544 u32 sid = task_sid(tsk);
3545 u32 perm;
3546 struct file_security_struct *fsec;
3547
3548 /* struct fown_struct is never outside the context of a struct file */
3549 file = container_of(fown, struct file, f_owner);
3550
3551 fsec = file->f_security;
3552
3553 if (!signum)
3554 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3555 else
3556 perm = signal_to_av(signum);
3557
3558 return avc_has_perm(fsec->fown_sid, sid,
3559 SECCLASS_PROCESS, perm, NULL);
3560}
3561
3562static int selinux_file_receive(struct file *file)
3563{
3564 const struct cred *cred = current_cred();
3565
3566 return file_has_perm(cred, file, file_to_av(file));
3567}
3568
3569static int selinux_file_open(struct file *file, const struct cred *cred)
3570{
3571 struct file_security_struct *fsec;
3572 struct inode_security_struct *isec;
3573
3574 fsec = file->f_security;
3575 isec = inode_security(file_inode(file));
3576 /*
3577 * Save inode label and policy sequence number
3578 * at open-time so that selinux_file_permission
3579 * can determine whether revalidation is necessary.
3580 * Task label is already saved in the file security
3581 * struct as its SID.
3582 */
3583 fsec->isid = isec->sid;
3584 fsec->pseqno = avc_policy_seqno();
3585 /*
3586 * Since the inode label or policy seqno may have changed
3587 * between the selinux_inode_permission check and the saving
3588 * of state above, recheck that access is still permitted.
3589 * Otherwise, access might never be revalidated against the
3590 * new inode label or new policy.
3591 * This check is not redundant - do not remove.
3592 */
3593 return file_path_has_perm(cred, file, open_file_to_av(file));
3594}
3595
3596/* task security operations */
3597
3598static int selinux_task_create(unsigned long clone_flags)
3599{
3600 return current_has_perm(current, PROCESS__FORK);
3601}
3602
3603/*
3604 * allocate the SELinux part of blank credentials
3605 */
3606static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3607{
3608 struct task_security_struct *tsec;
3609
3610 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3611 if (!tsec)
3612 return -ENOMEM;
3613
3614 cred->security = tsec;
3615 return 0;
3616}
3617
3618/*
3619 * detach and free the LSM part of a set of credentials
3620 */
3621static void selinux_cred_free(struct cred *cred)
3622{
3623 struct task_security_struct *tsec = cred->security;
3624
3625 /*
3626 * cred->security == NULL if security_cred_alloc_blank() or
3627 * security_prepare_creds() returned an error.
3628 */
3629 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3630 cred->security = (void *) 0x7UL;
3631 kfree(tsec);
3632}
3633
3634/*
3635 * prepare a new set of credentials for modification
3636 */
3637static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3638 gfp_t gfp)
3639{
3640 const struct task_security_struct *old_tsec;
3641 struct task_security_struct *tsec;
3642
3643 old_tsec = old->security;
3644
3645 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3646 if (!tsec)
3647 return -ENOMEM;
3648
3649 new->security = tsec;
3650 return 0;
3651}
3652
3653/*
3654 * transfer the SELinux data to a blank set of creds
3655 */
3656static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3657{
3658 const struct task_security_struct *old_tsec = old->security;
3659 struct task_security_struct *tsec = new->security;
3660
3661 *tsec = *old_tsec;
3662}
3663
3664/*
3665 * set the security data for a kernel service
3666 * - all the creation contexts are set to unlabelled
3667 */
3668static int selinux_kernel_act_as(struct cred *new, u32 secid)
3669{
3670 struct task_security_struct *tsec = new->security;
3671 u32 sid = current_sid();
3672 int ret;
3673
3674 ret = avc_has_perm(sid, secid,
3675 SECCLASS_KERNEL_SERVICE,
3676 KERNEL_SERVICE__USE_AS_OVERRIDE,
3677 NULL);
3678 if (ret == 0) {
3679 tsec->sid = secid;
3680 tsec->create_sid = 0;
3681 tsec->keycreate_sid = 0;
3682 tsec->sockcreate_sid = 0;
3683 }
3684 return ret;
3685}
3686
3687/*
3688 * set the file creation context in a security record to the same as the
3689 * objective context of the specified inode
3690 */
3691static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3692{
3693 struct inode_security_struct *isec = inode_security(inode);
3694 struct task_security_struct *tsec = new->security;
3695 u32 sid = current_sid();
3696 int ret;
3697
3698 ret = avc_has_perm(sid, isec->sid,
3699 SECCLASS_KERNEL_SERVICE,
3700 KERNEL_SERVICE__CREATE_FILES_AS,
3701 NULL);
3702
3703 if (ret == 0)
3704 tsec->create_sid = isec->sid;
3705 return ret;
3706}
3707
3708static int selinux_kernel_module_request(char *kmod_name)
3709{
3710 u32 sid;
3711 struct common_audit_data ad;
3712
3713 sid = task_sid(current);
3714
3715 ad.type = LSM_AUDIT_DATA_KMOD;
3716 ad.u.kmod_name = kmod_name;
3717
3718 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3719 SYSTEM__MODULE_REQUEST, &ad);
3720}
3721
3722static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3723{
3724 return current_has_perm(p, PROCESS__SETPGID);
3725}
3726
3727static int selinux_task_getpgid(struct task_struct *p)
3728{
3729 return current_has_perm(p, PROCESS__GETPGID);
3730}
3731
3732static int selinux_task_getsid(struct task_struct *p)
3733{
3734 return current_has_perm(p, PROCESS__GETSESSION);
3735}
3736
3737static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3738{
3739 *secid = task_sid(p);
3740}
3741
3742static int selinux_task_setnice(struct task_struct *p, int nice)
3743{
3744 return current_has_perm(p, PROCESS__SETSCHED);
3745}
3746
3747static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3748{
3749 return current_has_perm(p, PROCESS__SETSCHED);
3750}
3751
3752static int selinux_task_getioprio(struct task_struct *p)
3753{
3754 return current_has_perm(p, PROCESS__GETSCHED);
3755}
3756
3757static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3758 struct rlimit *new_rlim)
3759{
3760 struct rlimit *old_rlim = p->signal->rlim + resource;
3761
3762 /* Control the ability to change the hard limit (whether
3763 lowering or raising it), so that the hard limit can
3764 later be used as a safe reset point for the soft limit
3765 upon context transitions. See selinux_bprm_committing_creds. */
3766 if (old_rlim->rlim_max != new_rlim->rlim_max)
3767 return current_has_perm(p, PROCESS__SETRLIMIT);
3768
3769 return 0;
3770}
3771
3772static int selinux_task_setscheduler(struct task_struct *p)
3773{
3774 return current_has_perm(p, PROCESS__SETSCHED);
3775}
3776
3777static int selinux_task_getscheduler(struct task_struct *p)
3778{
3779 return current_has_perm(p, PROCESS__GETSCHED);
3780}
3781
3782static int selinux_task_movememory(struct task_struct *p)
3783{
3784 return current_has_perm(p, PROCESS__SETSCHED);
3785}
3786
3787static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3788 int sig, u32 secid)
3789{
3790 u32 perm;
3791 int rc;
3792
3793 if (!sig)
3794 perm = PROCESS__SIGNULL; /* null signal; existence test */
3795 else
3796 perm = signal_to_av(sig);
3797 if (secid)
3798 rc = avc_has_perm(secid, task_sid(p),
3799 SECCLASS_PROCESS, perm, NULL);
3800 else
3801 rc = current_has_perm(p, perm);
3802 return rc;
3803}
3804
3805static int selinux_task_wait(struct task_struct *p)
3806{
3807 return task_has_perm(p, current, PROCESS__SIGCHLD);
3808}
3809
3810static void selinux_task_to_inode(struct task_struct *p,
3811 struct inode *inode)
3812{
3813 struct inode_security_struct *isec = inode->i_security;
3814 u32 sid = task_sid(p);
3815
3816 isec->sid = sid;
3817 isec->initialized = LABEL_INITIALIZED;
3818}
3819
3820/* Returns error only if unable to parse addresses */
3821static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3822 struct common_audit_data *ad, u8 *proto)
3823{
3824 int offset, ihlen, ret = -EINVAL;
3825 struct iphdr _iph, *ih;
3826
3827 offset = skb_network_offset(skb);
3828 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3829 if (ih == NULL)
3830 goto out;
3831
3832 ihlen = ih->ihl * 4;
3833 if (ihlen < sizeof(_iph))
3834 goto out;
3835
3836 ad->u.net->v4info.saddr = ih->saddr;
3837 ad->u.net->v4info.daddr = ih->daddr;
3838 ret = 0;
3839
3840 if (proto)
3841 *proto = ih->protocol;
3842
3843 switch (ih->protocol) {
3844 case IPPROTO_TCP: {
3845 struct tcphdr _tcph, *th;
3846
3847 if (ntohs(ih->frag_off) & IP_OFFSET)
3848 break;
3849
3850 offset += ihlen;
3851 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3852 if (th == NULL)
3853 break;
3854
3855 ad->u.net->sport = th->source;
3856 ad->u.net->dport = th->dest;
3857 break;
3858 }
3859
3860 case IPPROTO_UDP: {
3861 struct udphdr _udph, *uh;
3862
3863 if (ntohs(ih->frag_off) & IP_OFFSET)
3864 break;
3865
3866 offset += ihlen;
3867 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3868 if (uh == NULL)
3869 break;
3870
3871 ad->u.net->sport = uh->source;
3872 ad->u.net->dport = uh->dest;
3873 break;
3874 }
3875
3876 case IPPROTO_DCCP: {
3877 struct dccp_hdr _dccph, *dh;
3878
3879 if (ntohs(ih->frag_off) & IP_OFFSET)
3880 break;
3881
3882 offset += ihlen;
3883 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3884 if (dh == NULL)
3885 break;
3886
3887 ad->u.net->sport = dh->dccph_sport;
3888 ad->u.net->dport = dh->dccph_dport;
3889 break;
3890 }
3891
3892 default:
3893 break;
3894 }
3895out:
3896 return ret;
3897}
3898
3899#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3900
3901/* Returns error only if unable to parse addresses */
3902static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3903 struct common_audit_data *ad, u8 *proto)
3904{
3905 u8 nexthdr;
3906 int ret = -EINVAL, offset;
3907 struct ipv6hdr _ipv6h, *ip6;
3908 __be16 frag_off;
3909
3910 offset = skb_network_offset(skb);
3911 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3912 if (ip6 == NULL)
3913 goto out;
3914
3915 ad->u.net->v6info.saddr = ip6->saddr;
3916 ad->u.net->v6info.daddr = ip6->daddr;
3917 ret = 0;
3918
3919 nexthdr = ip6->nexthdr;
3920 offset += sizeof(_ipv6h);
3921 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3922 if (offset < 0)
3923 goto out;
3924
3925 if (proto)
3926 *proto = nexthdr;
3927
3928 switch (nexthdr) {
3929 case IPPROTO_TCP: {
3930 struct tcphdr _tcph, *th;
3931
3932 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3933 if (th == NULL)
3934 break;
3935
3936 ad->u.net->sport = th->source;
3937 ad->u.net->dport = th->dest;
3938 break;
3939 }
3940
3941 case IPPROTO_UDP: {
3942 struct udphdr _udph, *uh;
3943
3944 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3945 if (uh == NULL)
3946 break;
3947
3948 ad->u.net->sport = uh->source;
3949 ad->u.net->dport = uh->dest;
3950 break;
3951 }
3952
3953 case IPPROTO_DCCP: {
3954 struct dccp_hdr _dccph, *dh;
3955
3956 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3957 if (dh == NULL)
3958 break;
3959
3960 ad->u.net->sport = dh->dccph_sport;
3961 ad->u.net->dport = dh->dccph_dport;
3962 break;
3963 }
3964
3965 /* includes fragments */
3966 default:
3967 break;
3968 }
3969out:
3970 return ret;
3971}
3972
3973#endif /* IPV6 */
3974
3975static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3976 char **_addrp, int src, u8 *proto)
3977{
3978 char *addrp;
3979 int ret;
3980
3981 switch (ad->u.net->family) {
3982 case PF_INET:
3983 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3984 if (ret)
3985 goto parse_error;
3986 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3987 &ad->u.net->v4info.daddr);
3988 goto okay;
3989
3990#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3991 case PF_INET6:
3992 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3993 if (ret)
3994 goto parse_error;
3995 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3996 &ad->u.net->v6info.daddr);
3997 goto okay;
3998#endif /* IPV6 */
3999 default:
4000 addrp = NULL;
4001 goto okay;
4002 }
4003
4004parse_error:
4005 printk(KERN_WARNING
4006 "SELinux: failure in selinux_parse_skb(),"
4007 " unable to parse packet\n");
4008 return ret;
4009
4010okay:
4011 if (_addrp)
4012 *_addrp = addrp;
4013 return 0;
4014}
4015
4016/**
4017 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4018 * @skb: the packet
4019 * @family: protocol family
4020 * @sid: the packet's peer label SID
4021 *
4022 * Description:
4023 * Check the various different forms of network peer labeling and determine
4024 * the peer label/SID for the packet; most of the magic actually occurs in
4025 * the security server function security_net_peersid_cmp(). The function
4026 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4027 * or -EACCES if @sid is invalid due to inconsistencies with the different
4028 * peer labels.
4029 *
4030 */
4031static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4032{
4033 int err;
4034 u32 xfrm_sid;
4035 u32 nlbl_sid;
4036 u32 nlbl_type;
4037
4038 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4039 if (unlikely(err))
4040 return -EACCES;
4041 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4042 if (unlikely(err))
4043 return -EACCES;
4044
4045 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
4046 if (unlikely(err)) {
4047 printk(KERN_WARNING
4048 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4049 " unable to determine packet's peer label\n");
4050 return -EACCES;
4051 }
4052
4053 return 0;
4054}
4055
4056/**
4057 * selinux_conn_sid - Determine the child socket label for a connection
4058 * @sk_sid: the parent socket's SID
4059 * @skb_sid: the packet's SID
4060 * @conn_sid: the resulting connection SID
4061 *
4062 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4063 * combined with the MLS information from @skb_sid in order to create
4064 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy
4065 * of @sk_sid. Returns zero on success, negative values on failure.
4066 *
4067 */
4068static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4069{
4070 int err = 0;
4071
4072 if (skb_sid != SECSID_NULL)
4073 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
4074 else
4075 *conn_sid = sk_sid;
4076
4077 return err;
4078}
4079
4080/* socket security operations */
4081
4082static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4083 u16 secclass, u32 *socksid)
4084{
4085 if (tsec->sockcreate_sid > SECSID_NULL) {
4086 *socksid = tsec->sockcreate_sid;
4087 return 0;
4088 }
4089
4090 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
4091 socksid);
4092}
4093
4094static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
4095{
4096 struct sk_security_struct *sksec = sk->sk_security;
4097 struct common_audit_data ad;
4098 struct lsm_network_audit net = {0,};
4099 u32 tsid = task_sid(task);
4100
4101 if (sksec->sid == SECINITSID_KERNEL)
4102 return 0;
4103
4104 ad.type = LSM_AUDIT_DATA_NET;
4105 ad.u.net = &net;
4106 ad.u.net->sk = sk;
4107
4108 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
4109}
4110
4111static int selinux_socket_create(int family, int type,
4112 int protocol, int kern)
4113{
4114 const struct task_security_struct *tsec = current_security();
4115 u32 newsid;
4116 u16 secclass;
4117 int rc;
4118
4119 if (kern)
4120 return 0;
4121
4122 secclass = socket_type_to_security_class(family, type, protocol);
4123 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4124 if (rc)
4125 return rc;
4126
4127 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4128}
4129
4130static int selinux_socket_post_create(struct socket *sock, int family,
4131 int type, int protocol, int kern)
4132{
4133 const struct task_security_struct *tsec = current_security();
4134 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4135 struct sk_security_struct *sksec;
4136 int err = 0;
4137
4138 isec->sclass = socket_type_to_security_class(family, type, protocol);
4139
4140 if (kern)
4141 isec->sid = SECINITSID_KERNEL;
4142 else {
4143 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
4144 if (err)
4145 return err;
4146 }
4147
4148 isec->initialized = LABEL_INITIALIZED;
4149
4150 if (sock->sk) {
4151 sksec = sock->sk->sk_security;
4152 sksec->sid = isec->sid;
4153 sksec->sclass = isec->sclass;
4154 err = selinux_netlbl_socket_post_create(sock->sk, family);
4155 }
4156
4157 return err;
4158}
4159
4160/* Range of port numbers used to automatically bind.
4161 Need to determine whether we should perform a name_bind
4162 permission check between the socket and the port number. */
4163
4164static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4165{
4166 struct sock *sk = sock->sk;
4167 u16 family;
4168 int err;
4169
4170 err = sock_has_perm(current, sk, SOCKET__BIND);
4171 if (err)
4172 goto out;
4173
4174 /*
4175 * If PF_INET or PF_INET6, check name_bind permission for the port.
4176 * Multiple address binding for SCTP is not supported yet: we just
4177 * check the first address now.
4178 */
4179 family = sk->sk_family;
4180 if (family == PF_INET || family == PF_INET6) {
4181 char *addrp;
4182 struct sk_security_struct *sksec = sk->sk_security;
4183 struct common_audit_data ad;
4184 struct lsm_network_audit net = {0,};
4185 struct sockaddr_in *addr4 = NULL;
4186 struct sockaddr_in6 *addr6 = NULL;
4187 unsigned short snum;
4188 u32 sid, node_perm;
4189
4190 if (family == PF_INET) {
4191 addr4 = (struct sockaddr_in *)address;
4192 snum = ntohs(addr4->sin_port);
4193 addrp = (char *)&addr4->sin_addr.s_addr;
4194 } else {
4195 addr6 = (struct sockaddr_in6 *)address;
4196 snum = ntohs(addr6->sin6_port);
4197 addrp = (char *)&addr6->sin6_addr.s6_addr;
4198 }
4199
4200 if (snum) {
4201 int low, high;
4202
4203 inet_get_local_port_range(sock_net(sk), &low, &high);
4204
4205 if (snum < max(PROT_SOCK, low) || snum > high) {
4206 err = sel_netport_sid(sk->sk_protocol,
4207 snum, &sid);
4208 if (err)
4209 goto out;
4210 ad.type = LSM_AUDIT_DATA_NET;
4211 ad.u.net = &net;
4212 ad.u.net->sport = htons(snum);
4213 ad.u.net->family = family;
4214 err = avc_has_perm(sksec->sid, sid,
4215 sksec->sclass,
4216 SOCKET__NAME_BIND, &ad);
4217 if (err)
4218 goto out;
4219 }
4220 }
4221
4222 switch (sksec->sclass) {
4223 case SECCLASS_TCP_SOCKET:
4224 node_perm = TCP_SOCKET__NODE_BIND;
4225 break;
4226
4227 case SECCLASS_UDP_SOCKET:
4228 node_perm = UDP_SOCKET__NODE_BIND;
4229 break;
4230
4231 case SECCLASS_DCCP_SOCKET:
4232 node_perm = DCCP_SOCKET__NODE_BIND;
4233 break;
4234
4235 default:
4236 node_perm = RAWIP_SOCKET__NODE_BIND;
4237 break;
4238 }
4239
4240 err = sel_netnode_sid(addrp, family, &sid);
4241 if (err)
4242 goto out;
4243
4244 ad.type = LSM_AUDIT_DATA_NET;
4245 ad.u.net = &net;
4246 ad.u.net->sport = htons(snum);
4247 ad.u.net->family = family;
4248
4249 if (family == PF_INET)
4250 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4251 else
4252 ad.u.net->v6info.saddr = addr6->sin6_addr;
4253
4254 err = avc_has_perm(sksec->sid, sid,
4255 sksec->sclass, node_perm, &ad);
4256 if (err)
4257 goto out;
4258 }
4259out:
4260 return err;
4261}
4262
4263static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4264{
4265 struct sock *sk = sock->sk;
4266 struct sk_security_struct *sksec = sk->sk_security;
4267 int err;
4268
4269 err = sock_has_perm(current, sk, SOCKET__CONNECT);
4270 if (err)
4271 return err;
4272
4273 /*
4274 * If a TCP or DCCP socket, check name_connect permission for the port.
4275 */
4276 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4277 sksec->sclass == SECCLASS_DCCP_SOCKET) {
4278 struct common_audit_data ad;
4279 struct lsm_network_audit net = {0,};
4280 struct sockaddr_in *addr4 = NULL;
4281 struct sockaddr_in6 *addr6 = NULL;
4282 unsigned short snum;
4283 u32 sid, perm;
4284
4285 if (sk->sk_family == PF_INET) {
4286 addr4 = (struct sockaddr_in *)address;
4287 if (addrlen < sizeof(struct sockaddr_in))
4288 return -EINVAL;
4289 snum = ntohs(addr4->sin_port);
4290 } else {
4291 addr6 = (struct sockaddr_in6 *)address;
4292 if (addrlen < SIN6_LEN_RFC2133)
4293 return -EINVAL;
4294 snum = ntohs(addr6->sin6_port);
4295 }
4296
4297 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4298 if (err)
4299 goto out;
4300
4301 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4302 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4303
4304 ad.type = LSM_AUDIT_DATA_NET;
4305 ad.u.net = &net;
4306 ad.u.net->dport = htons(snum);
4307 ad.u.net->family = sk->sk_family;
4308 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4309 if (err)
4310 goto out;
4311 }
4312
4313 err = selinux_netlbl_socket_connect(sk, address);
4314
4315out:
4316 return err;
4317}
4318
4319static int selinux_socket_listen(struct socket *sock, int backlog)
4320{
4321 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4322}
4323
4324static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4325{
4326 int err;
4327 struct inode_security_struct *isec;
4328 struct inode_security_struct *newisec;
4329
4330 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4331 if (err)
4332 return err;
4333
4334 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4335
4336 isec = inode_security_novalidate(SOCK_INODE(sock));
4337 newisec->sclass = isec->sclass;
4338 newisec->sid = isec->sid;
4339 newisec->initialized = LABEL_INITIALIZED;
4340
4341 return 0;
4342}
4343
4344static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4345 int size)
4346{
4347 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4348}
4349
4350static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4351 int size, int flags)
4352{
4353 return sock_has_perm(current, sock->sk, SOCKET__READ);
4354}
4355
4356static int selinux_socket_getsockname(struct socket *sock)
4357{
4358 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4359}
4360
4361static int selinux_socket_getpeername(struct socket *sock)
4362{
4363 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4364}
4365
4366static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4367{
4368 int err;
4369
4370 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4371 if (err)
4372 return err;
4373
4374 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4375}
4376
4377static int selinux_socket_getsockopt(struct socket *sock, int level,
4378 int optname)
4379{
4380 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4381}
4382
4383static int selinux_socket_shutdown(struct socket *sock, int how)
4384{
4385 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4386}
4387
4388static int selinux_socket_unix_stream_connect(struct sock *sock,
4389 struct sock *other,
4390 struct sock *newsk)
4391{
4392 struct sk_security_struct *sksec_sock = sock->sk_security;
4393 struct sk_security_struct *sksec_other = other->sk_security;
4394 struct sk_security_struct *sksec_new = newsk->sk_security;
4395 struct common_audit_data ad;
4396 struct lsm_network_audit net = {0,};
4397 int err;
4398
4399 ad.type = LSM_AUDIT_DATA_NET;
4400 ad.u.net = &net;
4401 ad.u.net->sk = other;
4402
4403 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4404 sksec_other->sclass,
4405 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4406 if (err)
4407 return err;
4408
4409 /* server child socket */
4410 sksec_new->peer_sid = sksec_sock->sid;
4411 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4412 &sksec_new->sid);
4413 if (err)
4414 return err;
4415
4416 /* connecting socket */
4417 sksec_sock->peer_sid = sksec_new->sid;
4418
4419 return 0;
4420}
4421
4422static int selinux_socket_unix_may_send(struct socket *sock,
4423 struct socket *other)
4424{
4425 struct sk_security_struct *ssec = sock->sk->sk_security;
4426 struct sk_security_struct *osec = other->sk->sk_security;
4427 struct common_audit_data ad;
4428 struct lsm_network_audit net = {0,};
4429
4430 ad.type = LSM_AUDIT_DATA_NET;
4431 ad.u.net = &net;
4432 ad.u.net->sk = other->sk;
4433
4434 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4435 &ad);
4436}
4437
4438static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4439 char *addrp, u16 family, u32 peer_sid,
4440 struct common_audit_data *ad)
4441{
4442 int err;
4443 u32 if_sid;
4444 u32 node_sid;
4445
4446 err = sel_netif_sid(ns, ifindex, &if_sid);
4447 if (err)
4448 return err;
4449 err = avc_has_perm(peer_sid, if_sid,
4450 SECCLASS_NETIF, NETIF__INGRESS, ad);
4451 if (err)
4452 return err;
4453
4454 err = sel_netnode_sid(addrp, family, &node_sid);
4455 if (err)
4456 return err;
4457 return avc_has_perm(peer_sid, node_sid,
4458 SECCLASS_NODE, NODE__RECVFROM, ad);
4459}
4460
4461static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4462 u16 family)
4463{
4464 int err = 0;
4465 struct sk_security_struct *sksec = sk->sk_security;
4466 u32 sk_sid = sksec->sid;
4467 struct common_audit_data ad;
4468 struct lsm_network_audit net = {0,};
4469 char *addrp;
4470
4471 ad.type = LSM_AUDIT_DATA_NET;
4472 ad.u.net = &net;
4473 ad.u.net->netif = skb->skb_iif;
4474 ad.u.net->family = family;
4475 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4476 if (err)
4477 return err;
4478
4479 if (selinux_secmark_enabled()) {
4480 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4481 PACKET__RECV, &ad);
4482 if (err)
4483 return err;
4484 }
4485
4486 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4487 if (err)
4488 return err;
4489 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4490
4491 return err;
4492}
4493
4494static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4495{
4496 int err;
4497 struct sk_security_struct *sksec = sk->sk_security;
4498 u16 family = sk->sk_family;
4499 u32 sk_sid = sksec->sid;
4500 struct common_audit_data ad;
4501 struct lsm_network_audit net = {0,};
4502 char *addrp;
4503 u8 secmark_active;
4504 u8 peerlbl_active;
4505
4506 if (family != PF_INET && family != PF_INET6)
4507 return 0;
4508
4509 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4510 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4511 family = PF_INET;
4512
4513 /* If any sort of compatibility mode is enabled then handoff processing
4514 * to the selinux_sock_rcv_skb_compat() function to deal with the
4515 * special handling. We do this in an attempt to keep this function
4516 * as fast and as clean as possible. */
4517 if (!selinux_policycap_netpeer)
4518 return selinux_sock_rcv_skb_compat(sk, skb, family);
4519
4520 secmark_active = selinux_secmark_enabled();
4521 peerlbl_active = selinux_peerlbl_enabled();
4522 if (!secmark_active && !peerlbl_active)
4523 return 0;
4524
4525 ad.type = LSM_AUDIT_DATA_NET;
4526 ad.u.net = &net;
4527 ad.u.net->netif = skb->skb_iif;
4528 ad.u.net->family = family;
4529 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4530 if (err)
4531 return err;
4532
4533 if (peerlbl_active) {
4534 u32 peer_sid;
4535
4536 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4537 if (err)
4538 return err;
4539 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
4540 addrp, family, peer_sid, &ad);
4541 if (err) {
4542 selinux_netlbl_err(skb, err, 0);
4543 return err;
4544 }
4545 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4546 PEER__RECV, &ad);
4547 if (err) {
4548 selinux_netlbl_err(skb, err, 0);
4549 return err;
4550 }
4551 }
4552
4553 if (secmark_active) {
4554 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4555 PACKET__RECV, &ad);
4556 if (err)
4557 return err;
4558 }
4559
4560 return err;
4561}
4562
4563static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4564 int __user *optlen, unsigned len)
4565{
4566 int err = 0;
4567 char *scontext;
4568 u32 scontext_len;
4569 struct sk_security_struct *sksec = sock->sk->sk_security;
4570 u32 peer_sid = SECSID_NULL;
4571
4572 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4573 sksec->sclass == SECCLASS_TCP_SOCKET)
4574 peer_sid = sksec->peer_sid;
4575 if (peer_sid == SECSID_NULL)
4576 return -ENOPROTOOPT;
4577
4578 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4579 if (err)
4580 return err;
4581
4582 if (scontext_len > len) {
4583 err = -ERANGE;
4584 goto out_len;
4585 }
4586
4587 if (copy_to_user(optval, scontext, scontext_len))
4588 err = -EFAULT;
4589
4590out_len:
4591 if (put_user(scontext_len, optlen))
4592 err = -EFAULT;
4593 kfree(scontext);
4594 return err;
4595}
4596
4597static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4598{
4599 u32 peer_secid = SECSID_NULL;
4600 u16 family;
4601
4602 if (skb && skb->protocol == htons(ETH_P_IP))
4603 family = PF_INET;
4604 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4605 family = PF_INET6;
4606 else if (sock)
4607 family = sock->sk->sk_family;
4608 else
4609 goto out;
4610
4611 if (sock && family == PF_UNIX)
4612 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4613 else if (skb)
4614 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4615
4616out:
4617 *secid = peer_secid;
4618 if (peer_secid == SECSID_NULL)
4619 return -EINVAL;
4620 return 0;
4621}
4622
4623static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4624{
4625 struct sk_security_struct *sksec;
4626
4627 sksec = kzalloc(sizeof(*sksec), priority);
4628 if (!sksec)
4629 return -ENOMEM;
4630
4631 sksec->peer_sid = SECINITSID_UNLABELED;
4632 sksec->sid = SECINITSID_UNLABELED;
4633 sksec->sclass = SECCLASS_SOCKET;
4634 selinux_netlbl_sk_security_reset(sksec);
4635 sk->sk_security = sksec;
4636
4637 return 0;
4638}
4639
4640static void selinux_sk_free_security(struct sock *sk)
4641{
4642 struct sk_security_struct *sksec = sk->sk_security;
4643
4644 sk->sk_security = NULL;
4645 selinux_netlbl_sk_security_free(sksec);
4646 kfree(sksec);
4647}
4648
4649static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4650{
4651 struct sk_security_struct *sksec = sk->sk_security;
4652 struct sk_security_struct *newsksec = newsk->sk_security;
4653
4654 newsksec->sid = sksec->sid;
4655 newsksec->peer_sid = sksec->peer_sid;
4656 newsksec->sclass = sksec->sclass;
4657
4658 selinux_netlbl_sk_security_reset(newsksec);
4659}
4660
4661static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4662{
4663 if (!sk)
4664 *secid = SECINITSID_ANY_SOCKET;
4665 else {
4666 struct sk_security_struct *sksec = sk->sk_security;
4667
4668 *secid = sksec->sid;
4669 }
4670}
4671
4672static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4673{
4674 struct inode_security_struct *isec =
4675 inode_security_novalidate(SOCK_INODE(parent));
4676 struct sk_security_struct *sksec = sk->sk_security;
4677
4678 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4679 sk->sk_family == PF_UNIX)
4680 isec->sid = sksec->sid;
4681 sksec->sclass = isec->sclass;
4682}
4683
4684static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4685 struct request_sock *req)
4686{
4687 struct sk_security_struct *sksec = sk->sk_security;
4688 int err;
4689 u16 family = req->rsk_ops->family;
4690 u32 connsid;
4691 u32 peersid;
4692
4693 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4694 if (err)
4695 return err;
4696 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
4697 if (err)
4698 return err;
4699 req->secid = connsid;
4700 req->peer_secid = peersid;
4701
4702 return selinux_netlbl_inet_conn_request(req, family);
4703}
4704
4705static void selinux_inet_csk_clone(struct sock *newsk,
4706 const struct request_sock *req)
4707{
4708 struct sk_security_struct *newsksec = newsk->sk_security;
4709
4710 newsksec->sid = req->secid;
4711 newsksec->peer_sid = req->peer_secid;
4712 /* NOTE: Ideally, we should also get the isec->sid for the
4713 new socket in sync, but we don't have the isec available yet.
4714 So we will wait until sock_graft to do it, by which
4715 time it will have been created and available. */
4716
4717 /* We don't need to take any sort of lock here as we are the only
4718 * thread with access to newsksec */
4719 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4720}
4721
4722static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4723{
4724 u16 family = sk->sk_family;
4725 struct sk_security_struct *sksec = sk->sk_security;
4726
4727 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4728 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4729 family = PF_INET;
4730
4731 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4732}
4733
4734static int selinux_secmark_relabel_packet(u32 sid)
4735{
4736 const struct task_security_struct *__tsec;
4737 u32 tsid;
4738
4739 __tsec = current_security();
4740 tsid = __tsec->sid;
4741
4742 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4743}
4744
4745static void selinux_secmark_refcount_inc(void)
4746{
4747 atomic_inc(&selinux_secmark_refcount);
4748}
4749
4750static void selinux_secmark_refcount_dec(void)
4751{
4752 atomic_dec(&selinux_secmark_refcount);
4753}
4754
4755static void selinux_req_classify_flow(const struct request_sock *req,
4756 struct flowi *fl)
4757{
4758 fl->flowi_secid = req->secid;
4759}
4760
4761static int selinux_tun_dev_alloc_security(void **security)
4762{
4763 struct tun_security_struct *tunsec;
4764
4765 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4766 if (!tunsec)
4767 return -ENOMEM;
4768 tunsec->sid = current_sid();
4769
4770 *security = tunsec;
4771 return 0;
4772}
4773
4774static void selinux_tun_dev_free_security(void *security)
4775{
4776 kfree(security);
4777}
4778
4779static int selinux_tun_dev_create(void)
4780{
4781 u32 sid = current_sid();
4782
4783 /* we aren't taking into account the "sockcreate" SID since the socket
4784 * that is being created here is not a socket in the traditional sense,
4785 * instead it is a private sock, accessible only to the kernel, and
4786 * representing a wide range of network traffic spanning multiple
4787 * connections unlike traditional sockets - check the TUN driver to
4788 * get a better understanding of why this socket is special */
4789
4790 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4791 NULL);
4792}
4793
4794static int selinux_tun_dev_attach_queue(void *security)
4795{
4796 struct tun_security_struct *tunsec = security;
4797
4798 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4799 TUN_SOCKET__ATTACH_QUEUE, NULL);
4800}
4801
4802static int selinux_tun_dev_attach(struct sock *sk, void *security)
4803{
4804 struct tun_security_struct *tunsec = security;
4805 struct sk_security_struct *sksec = sk->sk_security;
4806
4807 /* we don't currently perform any NetLabel based labeling here and it
4808 * isn't clear that we would want to do so anyway; while we could apply
4809 * labeling without the support of the TUN user the resulting labeled
4810 * traffic from the other end of the connection would almost certainly
4811 * cause confusion to the TUN user that had no idea network labeling
4812 * protocols were being used */
4813
4814 sksec->sid = tunsec->sid;
4815 sksec->sclass = SECCLASS_TUN_SOCKET;
4816
4817 return 0;
4818}
4819
4820static int selinux_tun_dev_open(void *security)
4821{
4822 struct tun_security_struct *tunsec = security;
4823 u32 sid = current_sid();
4824 int err;
4825
4826 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4827 TUN_SOCKET__RELABELFROM, NULL);
4828 if (err)
4829 return err;
4830 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4831 TUN_SOCKET__RELABELTO, NULL);
4832 if (err)
4833 return err;
4834 tunsec->sid = sid;
4835
4836 return 0;
4837}
4838
4839static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4840{
4841 int err = 0;
4842 u32 perm;
4843 struct nlmsghdr *nlh;
4844 struct sk_security_struct *sksec = sk->sk_security;
4845
4846 if (skb->len < NLMSG_HDRLEN) {
4847 err = -EINVAL;
4848 goto out;
4849 }
4850 nlh = nlmsg_hdr(skb);
4851
4852 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4853 if (err) {
4854 if (err == -EINVAL) {
4855 pr_warn_ratelimited("SELinux: unrecognized netlink"
4856 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
4857 " pig=%d comm=%s\n",
4858 sk->sk_protocol, nlh->nlmsg_type,
4859 secclass_map[sksec->sclass - 1].name,
4860 task_pid_nr(current), current->comm);
4861 if (!selinux_enforcing || security_get_allow_unknown())
4862 err = 0;
4863 }
4864
4865 /* Ignore */
4866 if (err == -ENOENT)
4867 err = 0;
4868 goto out;
4869 }
4870
4871 err = sock_has_perm(current, sk, perm);
4872out:
4873 return err;
4874}
4875
4876#ifdef CONFIG_NETFILTER
4877
4878static unsigned int selinux_ip_forward(struct sk_buff *skb,
4879 const struct net_device *indev,
4880 u16 family)
4881{
4882 int err;
4883 char *addrp;
4884 u32 peer_sid;
4885 struct common_audit_data ad;
4886 struct lsm_network_audit net = {0,};
4887 u8 secmark_active;
4888 u8 netlbl_active;
4889 u8 peerlbl_active;
4890
4891 if (!selinux_policycap_netpeer)
4892 return NF_ACCEPT;
4893
4894 secmark_active = selinux_secmark_enabled();
4895 netlbl_active = netlbl_enabled();
4896 peerlbl_active = selinux_peerlbl_enabled();
4897 if (!secmark_active && !peerlbl_active)
4898 return NF_ACCEPT;
4899
4900 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4901 return NF_DROP;
4902
4903 ad.type = LSM_AUDIT_DATA_NET;
4904 ad.u.net = &net;
4905 ad.u.net->netif = indev->ifindex;
4906 ad.u.net->family = family;
4907 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4908 return NF_DROP;
4909
4910 if (peerlbl_active) {
4911 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
4912 addrp, family, peer_sid, &ad);
4913 if (err) {
4914 selinux_netlbl_err(skb, err, 1);
4915 return NF_DROP;
4916 }
4917 }
4918
4919 if (secmark_active)
4920 if (avc_has_perm(peer_sid, skb->secmark,
4921 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4922 return NF_DROP;
4923
4924 if (netlbl_active)
4925 /* we do this in the FORWARD path and not the POST_ROUTING
4926 * path because we want to make sure we apply the necessary
4927 * labeling before IPsec is applied so we can leverage AH
4928 * protection */
4929 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4930 return NF_DROP;
4931
4932 return NF_ACCEPT;
4933}
4934
4935static unsigned int selinux_ipv4_forward(void *priv,
4936 struct sk_buff *skb,
4937 const struct nf_hook_state *state)
4938{
4939 return selinux_ip_forward(skb, state->in, PF_INET);
4940}
4941
4942#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4943static unsigned int selinux_ipv6_forward(void *priv,
4944 struct sk_buff *skb,
4945 const struct nf_hook_state *state)
4946{
4947 return selinux_ip_forward(skb, state->in, PF_INET6);
4948}
4949#endif /* IPV6 */
4950
4951static unsigned int selinux_ip_output(struct sk_buff *skb,
4952 u16 family)
4953{
4954 struct sock *sk;
4955 u32 sid;
4956
4957 if (!netlbl_enabled())
4958 return NF_ACCEPT;
4959
4960 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4961 * because we want to make sure we apply the necessary labeling
4962 * before IPsec is applied so we can leverage AH protection */
4963 sk = skb->sk;
4964 if (sk) {
4965 struct sk_security_struct *sksec;
4966
4967 if (sk_listener(sk))
4968 /* if the socket is the listening state then this
4969 * packet is a SYN-ACK packet which means it needs to
4970 * be labeled based on the connection/request_sock and
4971 * not the parent socket. unfortunately, we can't
4972 * lookup the request_sock yet as it isn't queued on
4973 * the parent socket until after the SYN-ACK is sent.
4974 * the "solution" is to simply pass the packet as-is
4975 * as any IP option based labeling should be copied
4976 * from the initial connection request (in the IP
4977 * layer). it is far from ideal, but until we get a
4978 * security label in the packet itself this is the
4979 * best we can do. */
4980 return NF_ACCEPT;
4981
4982 /* standard practice, label using the parent socket */
4983 sksec = sk->sk_security;
4984 sid = sksec->sid;
4985 } else
4986 sid = SECINITSID_KERNEL;
4987 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4988 return NF_DROP;
4989
4990 return NF_ACCEPT;
4991}
4992
4993static unsigned int selinux_ipv4_output(void *priv,
4994 struct sk_buff *skb,
4995 const struct nf_hook_state *state)
4996{
4997 return selinux_ip_output(skb, PF_INET);
4998}
4999
5000static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5001 int ifindex,
5002 u16 family)
5003{
5004 struct sock *sk = skb_to_full_sk(skb);
5005 struct sk_security_struct *sksec;
5006 struct common_audit_data ad;
5007 struct lsm_network_audit net = {0,};
5008 char *addrp;
5009 u8 proto;
5010
5011 if (sk == NULL)
5012 return NF_ACCEPT;
5013 sksec = sk->sk_security;
5014
5015 ad.type = LSM_AUDIT_DATA_NET;
5016 ad.u.net = &net;
5017 ad.u.net->netif = ifindex;
5018 ad.u.net->family = family;
5019 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5020 return NF_DROP;
5021
5022 if (selinux_secmark_enabled())
5023 if (avc_has_perm(sksec->sid, skb->secmark,
5024 SECCLASS_PACKET, PACKET__SEND, &ad))
5025 return NF_DROP_ERR(-ECONNREFUSED);
5026
5027 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5028 return NF_DROP_ERR(-ECONNREFUSED);
5029
5030 return NF_ACCEPT;
5031}
5032
5033static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5034 const struct net_device *outdev,
5035 u16 family)
5036{
5037 u32 secmark_perm;
5038 u32 peer_sid;
5039 int ifindex = outdev->ifindex;
5040 struct sock *sk;
5041 struct common_audit_data ad;
5042 struct lsm_network_audit net = {0,};
5043 char *addrp;
5044 u8 secmark_active;
5045 u8 peerlbl_active;
5046
5047 /* If any sort of compatibility mode is enabled then handoff processing
5048 * to the selinux_ip_postroute_compat() function to deal with the
5049 * special handling. We do this in an attempt to keep this function
5050 * as fast and as clean as possible. */
5051 if (!selinux_policycap_netpeer)
5052 return selinux_ip_postroute_compat(skb, ifindex, family);
5053
5054 secmark_active = selinux_secmark_enabled();
5055 peerlbl_active = selinux_peerlbl_enabled();
5056 if (!secmark_active && !peerlbl_active)
5057 return NF_ACCEPT;
5058
5059 sk = skb_to_full_sk(skb);
5060
5061#ifdef CONFIG_XFRM
5062 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5063 * packet transformation so allow the packet to pass without any checks
5064 * since we'll have another chance to perform access control checks
5065 * when the packet is on it's final way out.
5066 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5067 * is NULL, in this case go ahead and apply access control.
5068 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5069 * TCP listening state we cannot wait until the XFRM processing
5070 * is done as we will miss out on the SA label if we do;
5071 * unfortunately, this means more work, but it is only once per
5072 * connection. */
5073 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5074 !(sk && sk_listener(sk)))
5075 return NF_ACCEPT;
5076#endif
5077
5078 if (sk == NULL) {
5079 /* Without an associated socket the packet is either coming
5080 * from the kernel or it is being forwarded; check the packet
5081 * to determine which and if the packet is being forwarded
5082 * query the packet directly to determine the security label. */
5083 if (skb->skb_iif) {
5084 secmark_perm = PACKET__FORWARD_OUT;
5085 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5086 return NF_DROP;
5087 } else {
5088 secmark_perm = PACKET__SEND;
5089 peer_sid = SECINITSID_KERNEL;
5090 }
5091 } else if (sk_listener(sk)) {
5092 /* Locally generated packet but the associated socket is in the
5093 * listening state which means this is a SYN-ACK packet. In
5094 * this particular case the correct security label is assigned
5095 * to the connection/request_sock but unfortunately we can't
5096 * query the request_sock as it isn't queued on the parent
5097 * socket until after the SYN-ACK packet is sent; the only
5098 * viable choice is to regenerate the label like we do in
5099 * selinux_inet_conn_request(). See also selinux_ip_output()
5100 * for similar problems. */
5101 u32 skb_sid;
5102 struct sk_security_struct *sksec;
5103
5104 sksec = sk->sk_security;
5105 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5106 return NF_DROP;
5107 /* At this point, if the returned skb peerlbl is SECSID_NULL
5108 * and the packet has been through at least one XFRM
5109 * transformation then we must be dealing with the "final"
5110 * form of labeled IPsec packet; since we've already applied
5111 * all of our access controls on this packet we can safely
5112 * pass the packet. */
5113 if (skb_sid == SECSID_NULL) {
5114 switch (family) {
5115 case PF_INET:
5116 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5117 return NF_ACCEPT;
5118 break;
5119 case PF_INET6:
5120 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5121 return NF_ACCEPT;
5122 break;
5123 default:
5124 return NF_DROP_ERR(-ECONNREFUSED);
5125 }
5126 }
5127 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5128 return NF_DROP;
5129 secmark_perm = PACKET__SEND;
5130 } else {
5131 /* Locally generated packet, fetch the security label from the
5132 * associated socket. */
5133 struct sk_security_struct *sksec = sk->sk_security;
5134 peer_sid = sksec->sid;
5135 secmark_perm = PACKET__SEND;
5136 }
5137
5138 ad.type = LSM_AUDIT_DATA_NET;
5139 ad.u.net = &net;
5140 ad.u.net->netif = ifindex;
5141 ad.u.net->family = family;
5142 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5143 return NF_DROP;
5144
5145 if (secmark_active)
5146 if (avc_has_perm(peer_sid, skb->secmark,
5147 SECCLASS_PACKET, secmark_perm, &ad))
5148 return NF_DROP_ERR(-ECONNREFUSED);
5149
5150 if (peerlbl_active) {
5151 u32 if_sid;
5152 u32 node_sid;
5153
5154 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5155 return NF_DROP;
5156 if (avc_has_perm(peer_sid, if_sid,
5157 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5158 return NF_DROP_ERR(-ECONNREFUSED);
5159
5160 if (sel_netnode_sid(addrp, family, &node_sid))
5161 return NF_DROP;
5162 if (avc_has_perm(peer_sid, node_sid,
5163 SECCLASS_NODE, NODE__SENDTO, &ad))
5164 return NF_DROP_ERR(-ECONNREFUSED);
5165 }
5166
5167 return NF_ACCEPT;
5168}
5169
5170static unsigned int selinux_ipv4_postroute(void *priv,
5171 struct sk_buff *skb,
5172 const struct nf_hook_state *state)
5173{
5174 return selinux_ip_postroute(skb, state->out, PF_INET);
5175}
5176
5177#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5178static unsigned int selinux_ipv6_postroute(void *priv,
5179 struct sk_buff *skb,
5180 const struct nf_hook_state *state)
5181{
5182 return selinux_ip_postroute(skb, state->out, PF_INET6);
5183}
5184#endif /* IPV6 */
5185
5186#endif /* CONFIG_NETFILTER */
5187
5188static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5189{
5190 return selinux_nlmsg_perm(sk, skb);
5191}
5192
5193static int ipc_alloc_security(struct task_struct *task,
5194 struct kern_ipc_perm *perm,
5195 u16 sclass)
5196{
5197 struct ipc_security_struct *isec;
5198 u32 sid;
5199
5200 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5201 if (!isec)
5202 return -ENOMEM;
5203
5204 sid = task_sid(task);
5205 isec->sclass = sclass;
5206 isec->sid = sid;
5207 perm->security = isec;
5208
5209 return 0;
5210}
5211
5212static void ipc_free_security(struct kern_ipc_perm *perm)
5213{
5214 struct ipc_security_struct *isec = perm->security;
5215 perm->security = NULL;
5216 kfree(isec);
5217}
5218
5219static int msg_msg_alloc_security(struct msg_msg *msg)
5220{
5221 struct msg_security_struct *msec;
5222
5223 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5224 if (!msec)
5225 return -ENOMEM;
5226
5227 msec->sid = SECINITSID_UNLABELED;
5228 msg->security = msec;
5229
5230 return 0;
5231}
5232
5233static void msg_msg_free_security(struct msg_msg *msg)
5234{
5235 struct msg_security_struct *msec = msg->security;
5236
5237 msg->security = NULL;
5238 kfree(msec);
5239}
5240
5241static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5242 u32 perms)
5243{
5244 struct ipc_security_struct *isec;
5245 struct common_audit_data ad;
5246 u32 sid = current_sid();
5247
5248 isec = ipc_perms->security;
5249
5250 ad.type = LSM_AUDIT_DATA_IPC;
5251 ad.u.ipc_id = ipc_perms->key;
5252
5253 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5254}
5255
5256static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5257{
5258 return msg_msg_alloc_security(msg);
5259}
5260
5261static void selinux_msg_msg_free_security(struct msg_msg *msg)
5262{
5263 msg_msg_free_security(msg);
5264}
5265
5266/* message queue security operations */
5267static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
5268{
5269 struct ipc_security_struct *isec;
5270 struct common_audit_data ad;
5271 u32 sid = current_sid();
5272 int rc;
5273
5274 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
5275 if (rc)
5276 return rc;
5277
5278 isec = msq->q_perm.security;
5279
5280 ad.type = LSM_AUDIT_DATA_IPC;
5281 ad.u.ipc_id = msq->q_perm.key;
5282
5283 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5284 MSGQ__CREATE, &ad);
5285 if (rc) {
5286 ipc_free_security(&msq->q_perm);
5287 return rc;
5288 }
5289 return 0;
5290}
5291
5292static void selinux_msg_queue_free_security(struct msg_queue *msq)
5293{
5294 ipc_free_security(&msq->q_perm);
5295}
5296
5297static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5298{
5299 struct ipc_security_struct *isec;
5300 struct common_audit_data ad;
5301 u32 sid = current_sid();
5302
5303 isec = msq->q_perm.security;
5304
5305 ad.type = LSM_AUDIT_DATA_IPC;
5306 ad.u.ipc_id = msq->q_perm.key;
5307
5308 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5309 MSGQ__ASSOCIATE, &ad);
5310}
5311
5312static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5313{
5314 int err;
5315 int perms;
5316
5317 switch (cmd) {
5318 case IPC_INFO:
5319 case MSG_INFO:
5320 /* No specific object, just general system-wide information. */
5321 return task_has_system(current, SYSTEM__IPC_INFO);
5322 case IPC_STAT:
5323 case MSG_STAT:
5324 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5325 break;
5326 case IPC_SET:
5327 perms = MSGQ__SETATTR;
5328 break;
5329 case IPC_RMID:
5330 perms = MSGQ__DESTROY;
5331 break;
5332 default:
5333 return 0;
5334 }
5335
5336 err = ipc_has_perm(&msq->q_perm, perms);
5337 return err;
5338}
5339
5340static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5341{
5342 struct ipc_security_struct *isec;
5343 struct msg_security_struct *msec;
5344 struct common_audit_data ad;
5345 u32 sid = current_sid();
5346 int rc;
5347
5348 isec = msq->q_perm.security;
5349 msec = msg->security;
5350
5351 /*
5352 * First time through, need to assign label to the message
5353 */
5354 if (msec->sid == SECINITSID_UNLABELED) {
5355 /*
5356 * Compute new sid based on current process and
5357 * message queue this message will be stored in
5358 */
5359 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5360 NULL, &msec->sid);
5361 if (rc)
5362 return rc;
5363 }
5364
5365 ad.type = LSM_AUDIT_DATA_IPC;
5366 ad.u.ipc_id = msq->q_perm.key;
5367
5368 /* Can this process write to the queue? */
5369 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5370 MSGQ__WRITE, &ad);
5371 if (!rc)
5372 /* Can this process send the message */
5373 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5374 MSG__SEND, &ad);
5375 if (!rc)
5376 /* Can the message be put in the queue? */
5377 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5378 MSGQ__ENQUEUE, &ad);
5379
5380 return rc;
5381}
5382
5383static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5384 struct task_struct *target,
5385 long type, int mode)
5386{
5387 struct ipc_security_struct *isec;
5388 struct msg_security_struct *msec;
5389 struct common_audit_data ad;
5390 u32 sid = task_sid(target);
5391 int rc;
5392
5393 isec = msq->q_perm.security;
5394 msec = msg->security;
5395
5396 ad.type = LSM_AUDIT_DATA_IPC;
5397 ad.u.ipc_id = msq->q_perm.key;
5398
5399 rc = avc_has_perm(sid, isec->sid,
5400 SECCLASS_MSGQ, MSGQ__READ, &ad);
5401 if (!rc)
5402 rc = avc_has_perm(sid, msec->sid,
5403 SECCLASS_MSG, MSG__RECEIVE, &ad);
5404 return rc;
5405}
5406
5407/* Shared Memory security operations */
5408static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5409{
5410 struct ipc_security_struct *isec;
5411 struct common_audit_data ad;
5412 u32 sid = current_sid();
5413 int rc;
5414
5415 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5416 if (rc)
5417 return rc;
5418
5419 isec = shp->shm_perm.security;
5420
5421 ad.type = LSM_AUDIT_DATA_IPC;
5422 ad.u.ipc_id = shp->shm_perm.key;
5423
5424 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5425 SHM__CREATE, &ad);
5426 if (rc) {
5427 ipc_free_security(&shp->shm_perm);
5428 return rc;
5429 }
5430 return 0;
5431}
5432
5433static void selinux_shm_free_security(struct shmid_kernel *shp)
5434{
5435 ipc_free_security(&shp->shm_perm);
5436}
5437
5438static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5439{
5440 struct ipc_security_struct *isec;
5441 struct common_audit_data ad;
5442 u32 sid = current_sid();
5443
5444 isec = shp->shm_perm.security;
5445
5446 ad.type = LSM_AUDIT_DATA_IPC;
5447 ad.u.ipc_id = shp->shm_perm.key;
5448
5449 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5450 SHM__ASSOCIATE, &ad);
5451}
5452
5453/* Note, at this point, shp is locked down */
5454static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5455{
5456 int perms;
5457 int err;
5458
5459 switch (cmd) {
5460 case IPC_INFO:
5461 case SHM_INFO:
5462 /* No specific object, just general system-wide information. */
5463 return task_has_system(current, SYSTEM__IPC_INFO);
5464 case IPC_STAT:
5465 case SHM_STAT:
5466 perms = SHM__GETATTR | SHM__ASSOCIATE;
5467 break;
5468 case IPC_SET:
5469 perms = SHM__SETATTR;
5470 break;
5471 case SHM_LOCK:
5472 case SHM_UNLOCK:
5473 perms = SHM__LOCK;
5474 break;
5475 case IPC_RMID:
5476 perms = SHM__DESTROY;
5477 break;
5478 default:
5479 return 0;
5480 }
5481
5482 err = ipc_has_perm(&shp->shm_perm, perms);
5483 return err;
5484}
5485
5486static int selinux_shm_shmat(struct shmid_kernel *shp,
5487 char __user *shmaddr, int shmflg)
5488{
5489 u32 perms;
5490
5491 if (shmflg & SHM_RDONLY)
5492 perms = SHM__READ;
5493 else
5494 perms = SHM__READ | SHM__WRITE;
5495
5496 return ipc_has_perm(&shp->shm_perm, perms);
5497}
5498
5499/* Semaphore security operations */
5500static int selinux_sem_alloc_security(struct sem_array *sma)
5501{
5502 struct ipc_security_struct *isec;
5503 struct common_audit_data ad;
5504 u32 sid = current_sid();
5505 int rc;
5506
5507 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5508 if (rc)
5509 return rc;
5510
5511 isec = sma->sem_perm.security;
5512
5513 ad.type = LSM_AUDIT_DATA_IPC;
5514 ad.u.ipc_id = sma->sem_perm.key;
5515
5516 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5517 SEM__CREATE, &ad);
5518 if (rc) {
5519 ipc_free_security(&sma->sem_perm);
5520 return rc;
5521 }
5522 return 0;
5523}
5524
5525static void selinux_sem_free_security(struct sem_array *sma)
5526{
5527 ipc_free_security(&sma->sem_perm);
5528}
5529
5530static int selinux_sem_associate(struct sem_array *sma, int semflg)
5531{
5532 struct ipc_security_struct *isec;
5533 struct common_audit_data ad;
5534 u32 sid = current_sid();
5535
5536 isec = sma->sem_perm.security;
5537
5538 ad.type = LSM_AUDIT_DATA_IPC;
5539 ad.u.ipc_id = sma->sem_perm.key;
5540
5541 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5542 SEM__ASSOCIATE, &ad);
5543}
5544
5545/* Note, at this point, sma is locked down */
5546static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5547{
5548 int err;
5549 u32 perms;
5550
5551 switch (cmd) {
5552 case IPC_INFO:
5553 case SEM_INFO:
5554 /* No specific object, just general system-wide information. */
5555 return task_has_system(current, SYSTEM__IPC_INFO);
5556 case GETPID:
5557 case GETNCNT:
5558 case GETZCNT:
5559 perms = SEM__GETATTR;
5560 break;
5561 case GETVAL:
5562 case GETALL:
5563 perms = SEM__READ;
5564 break;
5565 case SETVAL:
5566 case SETALL:
5567 perms = SEM__WRITE;
5568 break;
5569 case IPC_RMID:
5570 perms = SEM__DESTROY;
5571 break;
5572 case IPC_SET:
5573 perms = SEM__SETATTR;
5574 break;
5575 case IPC_STAT:
5576 case SEM_STAT:
5577 perms = SEM__GETATTR | SEM__ASSOCIATE;
5578 break;
5579 default:
5580 return 0;
5581 }
5582
5583 err = ipc_has_perm(&sma->sem_perm, perms);
5584 return err;
5585}
5586
5587static int selinux_sem_semop(struct sem_array *sma,
5588 struct sembuf *sops, unsigned nsops, int alter)
5589{
5590 u32 perms;
5591
5592 if (alter)
5593 perms = SEM__READ | SEM__WRITE;
5594 else
5595 perms = SEM__READ;
5596
5597 return ipc_has_perm(&sma->sem_perm, perms);
5598}
5599
5600static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5601{
5602 u32 av = 0;
5603
5604 av = 0;
5605 if (flag & S_IRUGO)
5606 av |= IPC__UNIX_READ;
5607 if (flag & S_IWUGO)
5608 av |= IPC__UNIX_WRITE;
5609
5610 if (av == 0)
5611 return 0;
5612
5613 return ipc_has_perm(ipcp, av);
5614}
5615
5616static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5617{
5618 struct ipc_security_struct *isec = ipcp->security;
5619 *secid = isec->sid;
5620}
5621
5622static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5623{
5624 if (inode)
5625 inode_doinit_with_dentry(inode, dentry);
5626}
5627
5628static int selinux_getprocattr(struct task_struct *p,
5629 char *name, char **value)
5630{
5631 const struct task_security_struct *__tsec;
5632 u32 sid;
5633 int error;
5634 unsigned len;
5635
5636 if (current != p) {
5637 error = current_has_perm(p, PROCESS__GETATTR);
5638 if (error)
5639 return error;
5640 }
5641
5642 rcu_read_lock();
5643 __tsec = __task_cred(p)->security;
5644
5645 if (!strcmp(name, "current"))
5646 sid = __tsec->sid;
5647 else if (!strcmp(name, "prev"))
5648 sid = __tsec->osid;
5649 else if (!strcmp(name, "exec"))
5650 sid = __tsec->exec_sid;
5651 else if (!strcmp(name, "fscreate"))
5652 sid = __tsec->create_sid;
5653 else if (!strcmp(name, "keycreate"))
5654 sid = __tsec->keycreate_sid;
5655 else if (!strcmp(name, "sockcreate"))
5656 sid = __tsec->sockcreate_sid;
5657 else
5658 goto invalid;
5659 rcu_read_unlock();
5660
5661 if (!sid)
5662 return 0;
5663
5664 error = security_sid_to_context(sid, value, &len);
5665 if (error)
5666 return error;
5667 return len;
5668
5669invalid:
5670 rcu_read_unlock();
5671 return -EINVAL;
5672}
5673
5674static int selinux_setprocattr(struct task_struct *p,
5675 char *name, void *value, size_t size)
5676{
5677 struct task_security_struct *tsec;
5678 struct task_struct *tracer;
5679 struct cred *new;
5680 u32 sid = 0, ptsid;
5681 int error;
5682 char *str = value;
5683
5684 if (current != p) {
5685 /* SELinux only allows a process to change its own
5686 security attributes. */
5687 return -EACCES;
5688 }
5689
5690 /*
5691 * Basic control over ability to set these attributes at all.
5692 * current == p, but we'll pass them separately in case the
5693 * above restriction is ever removed.
5694 */
5695 if (!strcmp(name, "exec"))
5696 error = current_has_perm(p, PROCESS__SETEXEC);
5697 else if (!strcmp(name, "fscreate"))
5698 error = current_has_perm(p, PROCESS__SETFSCREATE);
5699 else if (!strcmp(name, "keycreate"))
5700 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5701 else if (!strcmp(name, "sockcreate"))
5702 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5703 else if (!strcmp(name, "current"))
5704 error = current_has_perm(p, PROCESS__SETCURRENT);
5705 else
5706 error = -EINVAL;
5707 if (error)
5708 return error;
5709
5710 /* Obtain a SID for the context, if one was specified. */
5711 if (size && str[1] && str[1] != '\n') {
5712 if (str[size-1] == '\n') {
5713 str[size-1] = 0;
5714 size--;
5715 }
5716 error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5717 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5718 if (!capable(CAP_MAC_ADMIN)) {
5719 struct audit_buffer *ab;
5720 size_t audit_size;
5721
5722 /* We strip a nul only if it is at the end, otherwise the
5723 * context contains a nul and we should audit that */
5724 if (str[size - 1] == '\0')
5725 audit_size = size - 1;
5726 else
5727 audit_size = size;
5728 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5729 audit_log_format(ab, "op=fscreate invalid_context=");
5730 audit_log_n_untrustedstring(ab, value, audit_size);
5731 audit_log_end(ab);
5732
5733 return error;
5734 }
5735 error = security_context_to_sid_force(value, size,
5736 &sid);
5737 }
5738 if (error)
5739 return error;
5740 }
5741
5742 new = prepare_creds();
5743 if (!new)
5744 return -ENOMEM;
5745
5746 /* Permission checking based on the specified context is
5747 performed during the actual operation (execve,
5748 open/mkdir/...), when we know the full context of the
5749 operation. See selinux_bprm_set_creds for the execve
5750 checks and may_create for the file creation checks. The
5751 operation will then fail if the context is not permitted. */
5752 tsec = new->security;
5753 if (!strcmp(name, "exec")) {
5754 tsec->exec_sid = sid;
5755 } else if (!strcmp(name, "fscreate")) {
5756 tsec->create_sid = sid;
5757 } else if (!strcmp(name, "keycreate")) {
5758 error = may_create_key(sid, p);
5759 if (error)
5760 goto abort_change;
5761 tsec->keycreate_sid = sid;
5762 } else if (!strcmp(name, "sockcreate")) {
5763 tsec->sockcreate_sid = sid;
5764 } else if (!strcmp(name, "current")) {
5765 error = -EINVAL;
5766 if (sid == 0)
5767 goto abort_change;
5768
5769 /* Only allow single threaded processes to change context */
5770 error = -EPERM;
5771 if (!current_is_single_threaded()) {
5772 error = security_bounded_transition(tsec->sid, sid);
5773 if (error)
5774 goto abort_change;
5775 }
5776
5777 /* Check permissions for the transition. */
5778 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5779 PROCESS__DYNTRANSITION, NULL);
5780 if (error)
5781 goto abort_change;
5782
5783 /* Check for ptracing, and update the task SID if ok.
5784 Otherwise, leave SID unchanged and fail. */
5785 ptsid = 0;
5786 rcu_read_lock();
5787 tracer = ptrace_parent(p);
5788 if (tracer)
5789 ptsid = task_sid(tracer);
5790 rcu_read_unlock();
5791
5792 if (tracer) {
5793 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5794 PROCESS__PTRACE, NULL);
5795 if (error)
5796 goto abort_change;
5797 }
5798
5799 tsec->sid = sid;
5800 } else {
5801 error = -EINVAL;
5802 goto abort_change;
5803 }
5804
5805 commit_creds(new);
5806 return size;
5807
5808abort_change:
5809 abort_creds(new);
5810 return error;
5811}
5812
5813static int selinux_ismaclabel(const char *name)
5814{
5815 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5816}
5817
5818static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5819{
5820 return security_sid_to_context(secid, secdata, seclen);
5821}
5822
5823static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5824{
5825 return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5826}
5827
5828static void selinux_release_secctx(char *secdata, u32 seclen)
5829{
5830 kfree(secdata);
5831}
5832
5833static void selinux_inode_invalidate_secctx(struct inode *inode)
5834{
5835 struct inode_security_struct *isec = inode->i_security;
5836
5837 mutex_lock(&isec->lock);
5838 isec->initialized = LABEL_INVALID;
5839 mutex_unlock(&isec->lock);
5840}
5841
5842/*
5843 * called with inode->i_mutex locked
5844 */
5845static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5846{
5847 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5848}
5849
5850/*
5851 * called with inode->i_mutex locked
5852 */
5853static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5854{
5855 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5856}
5857
5858static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5859{
5860 int len = 0;
5861 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5862 ctx, true);
5863 if (len < 0)
5864 return len;
5865 *ctxlen = len;
5866 return 0;
5867}
5868#ifdef CONFIG_KEYS
5869
5870static int selinux_key_alloc(struct key *k, const struct cred *cred,
5871 unsigned long flags)
5872{
5873 const struct task_security_struct *tsec;
5874 struct key_security_struct *ksec;
5875
5876 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5877 if (!ksec)
5878 return -ENOMEM;
5879
5880 tsec = cred->security;
5881 if (tsec->keycreate_sid)
5882 ksec->sid = tsec->keycreate_sid;
5883 else
5884 ksec->sid = tsec->sid;
5885
5886 k->security = ksec;
5887 return 0;
5888}
5889
5890static void selinux_key_free(struct key *k)
5891{
5892 struct key_security_struct *ksec = k->security;
5893
5894 k->security = NULL;
5895 kfree(ksec);
5896}
5897
5898static int selinux_key_permission(key_ref_t key_ref,
5899 const struct cred *cred,
5900 unsigned perm)
5901{
5902 struct key *key;
5903 struct key_security_struct *ksec;
5904 u32 sid;
5905
5906 /* if no specific permissions are requested, we skip the
5907 permission check. No serious, additional covert channels
5908 appear to be created. */
5909 if (perm == 0)
5910 return 0;
5911
5912 sid = cred_sid(cred);
5913
5914 key = key_ref_to_ptr(key_ref);
5915 ksec = key->security;
5916
5917 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5918}
5919
5920static int selinux_key_getsecurity(struct key *key, char **_buffer)
5921{
5922 struct key_security_struct *ksec = key->security;
5923 char *context = NULL;
5924 unsigned len;
5925 int rc;
5926
5927 rc = security_sid_to_context(ksec->sid, &context, &len);
5928 if (!rc)
5929 rc = len;
5930 *_buffer = context;
5931 return rc;
5932}
5933
5934#endif
5935
5936static struct security_hook_list selinux_hooks[] = {
5937 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
5938 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
5939 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
5940 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
5941
5942 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
5943 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
5944 LSM_HOOK_INIT(capget, selinux_capget),
5945 LSM_HOOK_INIT(capset, selinux_capset),
5946 LSM_HOOK_INIT(capable, selinux_capable),
5947 LSM_HOOK_INIT(quotactl, selinux_quotactl),
5948 LSM_HOOK_INIT(quota_on, selinux_quota_on),
5949 LSM_HOOK_INIT(syslog, selinux_syslog),
5950 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
5951
5952 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
5953
5954 LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
5955 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
5956 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
5957 LSM_HOOK_INIT(bprm_secureexec, selinux_bprm_secureexec),
5958
5959 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
5960 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
5961 LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
5962 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
5963 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
5964 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
5965 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
5966 LSM_HOOK_INIT(sb_mount, selinux_mount),
5967 LSM_HOOK_INIT(sb_umount, selinux_umount),
5968 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
5969 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
5970 LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),
5971
5972 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
5973
5974 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
5975 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
5976 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
5977 LSM_HOOK_INIT(inode_create, selinux_inode_create),
5978 LSM_HOOK_INIT(inode_link, selinux_inode_link),
5979 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
5980 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
5981 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
5982 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
5983 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
5984 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
5985 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
5986 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
5987 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
5988 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
5989 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
5990 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
5991 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
5992 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
5993 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
5994 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
5995 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
5996 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
5997 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
5998 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
5999
6000 LSM_HOOK_INIT(file_permission, selinux_file_permission),
6001 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
6002 LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
6003 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
6004 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
6005 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
6006 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
6007 LSM_HOOK_INIT(file_lock, selinux_file_lock),
6008 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
6009 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
6010 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
6011 LSM_HOOK_INIT(file_receive, selinux_file_receive),
6012
6013 LSM_HOOK_INIT(file_open, selinux_file_open),
6014
6015 LSM_HOOK_INIT(task_create, selinux_task_create),
6016 LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
6017 LSM_HOOK_INIT(cred_free, selinux_cred_free),
6018 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
6019 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
6020 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
6021 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
6022 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6023 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
6024 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
6025 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
6026 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
6027 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
6028 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
6029 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6030 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
6031 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
6032 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
6033 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
6034 LSM_HOOK_INIT(task_kill, selinux_task_kill),
6035 LSM_HOOK_INIT(task_wait, selinux_task_wait),
6036 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
6037
6038 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
6039 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
6040
6041 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
6042 LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),
6043
6044 LSM_HOOK_INIT(msg_queue_alloc_security,
6045 selinux_msg_queue_alloc_security),
6046 LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
6047 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
6048 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
6049 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
6050 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
6051
6052 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
6053 LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
6054 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
6055 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
6056 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
6057
6058 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
6059 LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
6060 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
6061 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
6062 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
6063
6064 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
6065
6066 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
6067 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
6068
6069 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
6070 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
6071 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
6072 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
6073 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6074 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
6075 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
6076 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
6077
6078 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
6079 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
6080
6081 LSM_HOOK_INIT(socket_create, selinux_socket_create),
6082 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
6083 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
6084 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
6085 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
6086 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
6087 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
6088 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
6089 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
6090 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
6091 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
6092 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
6093 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
6094 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
6095 LSM_HOOK_INIT(socket_getpeersec_stream,
6096 selinux_socket_getpeersec_stream),
6097 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
6098 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
6099 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
6100 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
6101 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
6102 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
6103 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
6104 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
6105 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
6106 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
6107 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
6108 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
6109 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
6110 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
6111 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
6112 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
6113 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
6114 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
6115 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
6116
6117#ifdef CONFIG_SECURITY_NETWORK_XFRM
6118 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
6119 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
6120 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
6121 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
6122 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
6123 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
6124 selinux_xfrm_state_alloc_acquire),
6125 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
6126 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
6127 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
6128 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
6129 selinux_xfrm_state_pol_flow_match),
6130 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
6131#endif
6132
6133#ifdef CONFIG_KEYS
6134 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
6135 LSM_HOOK_INIT(key_free, selinux_key_free),
6136 LSM_HOOK_INIT(key_permission, selinux_key_permission),
6137 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
6138#endif
6139
6140#ifdef CONFIG_AUDIT
6141 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
6142 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
6143 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
6144 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
6145#endif
6146};
6147
6148static __init int selinux_init(void)
6149{
6150 if (!security_module_enable("selinux")) {
6151 selinux_enabled = 0;
6152 return 0;
6153 }
6154
6155 if (!selinux_enabled) {
6156 printk(KERN_INFO "SELinux: Disabled at boot.\n");
6157 return 0;
6158 }
6159
6160 printk(KERN_INFO "SELinux: Initializing.\n");
6161
6162 /* Set the security state for the initial task. */
6163 cred_init_security();
6164
6165 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
6166
6167 sel_inode_cache = kmem_cache_create("selinux_inode_security",
6168 sizeof(struct inode_security_struct),
6169 0, SLAB_PANIC, NULL);
6170 file_security_cache = kmem_cache_create("selinux_file_security",
6171 sizeof(struct file_security_struct),
6172 0, SLAB_PANIC, NULL);
6173 avc_init();
6174
6175 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
6176
6177 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
6178 panic("SELinux: Unable to register AVC netcache callback\n");
6179
6180 if (selinux_enforcing)
6181 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
6182 else
6183 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
6184
6185 return 0;
6186}
6187
6188static void delayed_superblock_init(struct super_block *sb, void *unused)
6189{
6190 superblock_doinit(sb, NULL);
6191}
6192
6193void selinux_complete_init(void)
6194{
6195 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
6196
6197 /* Set up any superblocks initialized prior to the policy load. */
6198 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
6199 iterate_supers(delayed_superblock_init, NULL);
6200}
6201
6202/* SELinux requires early initialization in order to label
6203 all processes and objects when they are created. */
6204security_initcall(selinux_init);
6205
6206#if defined(CONFIG_NETFILTER)
6207
6208static struct nf_hook_ops selinux_nf_ops[] = {
6209 {
6210 .hook = selinux_ipv4_postroute,
6211 .pf = NFPROTO_IPV4,
6212 .hooknum = NF_INET_POST_ROUTING,
6213 .priority = NF_IP_PRI_SELINUX_LAST,
6214 },
6215 {
6216 .hook = selinux_ipv4_forward,
6217 .pf = NFPROTO_IPV4,
6218 .hooknum = NF_INET_FORWARD,
6219 .priority = NF_IP_PRI_SELINUX_FIRST,
6220 },
6221 {
6222 .hook = selinux_ipv4_output,
6223 .pf = NFPROTO_IPV4,
6224 .hooknum = NF_INET_LOCAL_OUT,
6225 .priority = NF_IP_PRI_SELINUX_FIRST,
6226 },
6227#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6228 {
6229 .hook = selinux_ipv6_postroute,
6230 .pf = NFPROTO_IPV6,
6231 .hooknum = NF_INET_POST_ROUTING,
6232 .priority = NF_IP6_PRI_SELINUX_LAST,
6233 },
6234 {
6235 .hook = selinux_ipv6_forward,
6236 .pf = NFPROTO_IPV6,
6237 .hooknum = NF_INET_FORWARD,
6238 .priority = NF_IP6_PRI_SELINUX_FIRST,
6239 },
6240#endif /* IPV6 */
6241};
6242
6243static int __init selinux_nf_ip_init(void)
6244{
6245 int err;
6246
6247 if (!selinux_enabled)
6248 return 0;
6249
6250 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
6251
6252 err = nf_register_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6253 if (err)
6254 panic("SELinux: nf_register_hooks: error %d\n", err);
6255
6256 return 0;
6257}
6258
6259__initcall(selinux_nf_ip_init);
6260
6261#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6262static void selinux_nf_ip_exit(void)
6263{
6264 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
6265
6266 nf_unregister_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6267}
6268#endif
6269
6270#else /* CONFIG_NETFILTER */
6271
6272#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6273#define selinux_nf_ip_exit()
6274#endif
6275
6276#endif /* CONFIG_NETFILTER */
6277
6278#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6279static int selinux_disabled;
6280
6281int selinux_disable(void)
6282{
6283 if (ss_initialized) {
6284 /* Not permitted after initial policy load. */
6285 return -EINVAL;
6286 }
6287
6288 if (selinux_disabled) {
6289 /* Only do this once. */
6290 return -EINVAL;
6291 }
6292
6293 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
6294
6295 selinux_disabled = 1;
6296 selinux_enabled = 0;
6297
6298 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
6299
6300 /* Try to destroy the avc node cache */
6301 avc_disable();
6302
6303 /* Unregister netfilter hooks. */
6304 selinux_nf_ip_exit();
6305
6306 /* Unregister selinuxfs. */
6307 exit_sel_fs();
6308
6309 return 0;
6310}
6311#endif
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * NSA Security-Enhanced Linux (SELinux) security module
4 *
5 * This file contains the SELinux hook function implementations.
6 *
7 * Authors: Stephen Smalley, <sds@tycho.nsa.gov>
8 * Chris Vance, <cvance@nai.com>
9 * Wayne Salamon, <wsalamon@nai.com>
10 * James Morris <jmorris@redhat.com>
11 *
12 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
13 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
14 * Eric Paris <eparis@redhat.com>
15 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
16 * <dgoeddel@trustedcs.com>
17 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
18 * Paul Moore <paul@paul-moore.com>
19 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
20 * Yuichi Nakamura <ynakam@hitachisoft.jp>
21 * Copyright (C) 2016 Mellanox Technologies
22 */
23
24#include <linux/init.h>
25#include <linux/kd.h>
26#include <linux/kernel.h>
27#include <linux/kernel_read_file.h>
28#include <linux/tracehook.h>
29#include <linux/errno.h>
30#include <linux/sched/signal.h>
31#include <linux/sched/task.h>
32#include <linux/lsm_hooks.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/fs_context.h>
50#include <linux/fs_parser.h>
51#include <linux/netfilter_ipv4.h>
52#include <linux/netfilter_ipv6.h>
53#include <linux/tty.h>
54#include <net/icmp.h>
55#include <net/ip.h> /* for local_port_range[] */
56#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
57#include <net/inet_connection_sock.h>
58#include <net/net_namespace.h>
59#include <net/netlabel.h>
60#include <linux/uaccess.h>
61#include <asm/ioctls.h>
62#include <linux/atomic.h>
63#include <linux/bitops.h>
64#include <linux/interrupt.h>
65#include <linux/netdevice.h> /* for network interface checks */
66#include <net/netlink.h>
67#include <linux/tcp.h>
68#include <linux/udp.h>
69#include <linux/dccp.h>
70#include <linux/sctp.h>
71#include <net/sctp/structs.h>
72#include <linux/quota.h>
73#include <linux/un.h> /* for Unix socket types */
74#include <net/af_unix.h> /* for Unix socket types */
75#include <linux/parser.h>
76#include <linux/nfs_mount.h>
77#include <net/ipv6.h>
78#include <linux/hugetlb.h>
79#include <linux/personality.h>
80#include <linux/audit.h>
81#include <linux/string.h>
82#include <linux/mutex.h>
83#include <linux/posix-timers.h>
84#include <linux/syslog.h>
85#include <linux/user_namespace.h>
86#include <linux/export.h>
87#include <linux/msg.h>
88#include <linux/shm.h>
89#include <linux/bpf.h>
90#include <linux/kernfs.h>
91#include <linux/stringhash.h> /* for hashlen_string() */
92#include <uapi/linux/mount.h>
93#include <linux/fsnotify.h>
94#include <linux/fanotify.h>
95
96#include "avc.h"
97#include "objsec.h"
98#include "netif.h"
99#include "netnode.h"
100#include "netport.h"
101#include "ibpkey.h"
102#include "xfrm.h"
103#include "netlabel.h"
104#include "audit.h"
105#include "avc_ss.h"
106
107struct selinux_state selinux_state;
108
109/* SECMARK reference count */
110static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
111
112#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
113static int selinux_enforcing_boot __initdata;
114
115static int __init enforcing_setup(char *str)
116{
117 unsigned long enforcing;
118 if (!kstrtoul(str, 0, &enforcing))
119 selinux_enforcing_boot = enforcing ? 1 : 0;
120 return 1;
121}
122__setup("enforcing=", enforcing_setup);
123#else
124#define selinux_enforcing_boot 1
125#endif
126
127int selinux_enabled_boot __initdata = 1;
128#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
129static int __init selinux_enabled_setup(char *str)
130{
131 unsigned long enabled;
132 if (!kstrtoul(str, 0, &enabled))
133 selinux_enabled_boot = enabled ? 1 : 0;
134 return 1;
135}
136__setup("selinux=", selinux_enabled_setup);
137#endif
138
139static unsigned int selinux_checkreqprot_boot =
140 CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
141
142static int __init checkreqprot_setup(char *str)
143{
144 unsigned long checkreqprot;
145
146 if (!kstrtoul(str, 0, &checkreqprot)) {
147 selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
148 if (checkreqprot)
149 pr_warn("SELinux: checkreqprot set to 1 via kernel parameter. This is deprecated and will be rejected in a future kernel release.\n");
150 }
151 return 1;
152}
153__setup("checkreqprot=", checkreqprot_setup);
154
155/**
156 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
157 *
158 * Description:
159 * This function checks the SECMARK reference counter to see if any SECMARK
160 * targets are currently configured, if the reference counter is greater than
161 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
162 * enabled, false (0) if SECMARK is disabled. If the always_check_network
163 * policy capability is enabled, SECMARK is always considered enabled.
164 *
165 */
166static int selinux_secmark_enabled(void)
167{
168 return (selinux_policycap_alwaysnetwork() ||
169 atomic_read(&selinux_secmark_refcount));
170}
171
172/**
173 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
174 *
175 * Description:
176 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true
177 * (1) if any are enabled or false (0) if neither are enabled. If the
178 * always_check_network policy capability is enabled, peer labeling
179 * is always considered enabled.
180 *
181 */
182static int selinux_peerlbl_enabled(void)
183{
184 return (selinux_policycap_alwaysnetwork() ||
185 netlbl_enabled() || selinux_xfrm_enabled());
186}
187
188static int selinux_netcache_avc_callback(u32 event)
189{
190 if (event == AVC_CALLBACK_RESET) {
191 sel_netif_flush();
192 sel_netnode_flush();
193 sel_netport_flush();
194 synchronize_net();
195 }
196 return 0;
197}
198
199static int selinux_lsm_notifier_avc_callback(u32 event)
200{
201 if (event == AVC_CALLBACK_RESET) {
202 sel_ib_pkey_flush();
203 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
204 }
205
206 return 0;
207}
208
209/*
210 * initialise the security for the init task
211 */
212static void cred_init_security(void)
213{
214 struct cred *cred = (struct cred *) current->real_cred;
215 struct task_security_struct *tsec;
216
217 tsec = selinux_cred(cred);
218 tsec->osid = tsec->sid = SECINITSID_KERNEL;
219}
220
221/*
222 * get the security ID of a set of credentials
223 */
224static inline u32 cred_sid(const struct cred *cred)
225{
226 const struct task_security_struct *tsec;
227
228 tsec = selinux_cred(cred);
229 return tsec->sid;
230}
231
232/*
233 * get the subjective security ID of a task
234 */
235static inline u32 task_sid_subj(const struct task_struct *task)
236{
237 u32 sid;
238
239 rcu_read_lock();
240 sid = cred_sid(rcu_dereference(task->cred));
241 rcu_read_unlock();
242 return sid;
243}
244
245/*
246 * get the objective security ID of a task
247 */
248static inline u32 task_sid_obj(const struct task_struct *task)
249{
250 u32 sid;
251
252 rcu_read_lock();
253 sid = cred_sid(__task_cred(task));
254 rcu_read_unlock();
255 return sid;
256}
257
258/*
259 * get the security ID of a task for use with binder
260 */
261static inline u32 task_sid_binder(const struct task_struct *task)
262{
263 /*
264 * In many case where this function is used we should be using the
265 * task's subjective SID, but we can't reliably access the subjective
266 * creds of a task other than our own so we must use the objective
267 * creds/SID, which are safe to access. The downside is that if a task
268 * is temporarily overriding it's creds it will not be reflected here;
269 * however, it isn't clear that binder would handle that case well
270 * anyway.
271 *
272 * If this ever changes and we can safely reference the subjective
273 * creds/SID of another task, this function will make it easier to
274 * identify the various places where we make use of the task SIDs in
275 * the binder code. It is also likely that we will need to adjust
276 * the main drivers/android binder code as well.
277 */
278 return task_sid_obj(task);
279}
280
281static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
282
283/*
284 * Try reloading inode security labels that have been marked as invalid. The
285 * @may_sleep parameter indicates when sleeping and thus reloading labels is
286 * allowed; when set to false, returns -ECHILD when the label is
287 * invalid. The @dentry parameter should be set to a dentry of the inode.
288 */
289static int __inode_security_revalidate(struct inode *inode,
290 struct dentry *dentry,
291 bool may_sleep)
292{
293 struct inode_security_struct *isec = selinux_inode(inode);
294
295 might_sleep_if(may_sleep);
296
297 if (selinux_initialized(&selinux_state) &&
298 isec->initialized != LABEL_INITIALIZED) {
299 if (!may_sleep)
300 return -ECHILD;
301
302 /*
303 * Try reloading the inode security label. This will fail if
304 * @opt_dentry is NULL and no dentry for this inode can be
305 * found; in that case, continue using the old label.
306 */
307 inode_doinit_with_dentry(inode, dentry);
308 }
309 return 0;
310}
311
312static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
313{
314 return selinux_inode(inode);
315}
316
317static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
318{
319 int error;
320
321 error = __inode_security_revalidate(inode, NULL, !rcu);
322 if (error)
323 return ERR_PTR(error);
324 return selinux_inode(inode);
325}
326
327/*
328 * Get the security label of an inode.
329 */
330static struct inode_security_struct *inode_security(struct inode *inode)
331{
332 __inode_security_revalidate(inode, NULL, true);
333 return selinux_inode(inode);
334}
335
336static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
337{
338 struct inode *inode = d_backing_inode(dentry);
339
340 return selinux_inode(inode);
341}
342
343/*
344 * Get the security label of a dentry's backing inode.
345 */
346static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
347{
348 struct inode *inode = d_backing_inode(dentry);
349
350 __inode_security_revalidate(inode, dentry, true);
351 return selinux_inode(inode);
352}
353
354static void inode_free_security(struct inode *inode)
355{
356 struct inode_security_struct *isec = selinux_inode(inode);
357 struct superblock_security_struct *sbsec;
358
359 if (!isec)
360 return;
361 sbsec = selinux_superblock(inode->i_sb);
362 /*
363 * As not all inode security structures are in a list, we check for
364 * empty list outside of the lock to make sure that we won't waste
365 * time taking a lock doing nothing.
366 *
367 * The list_del_init() function can be safely called more than once.
368 * It should not be possible for this function to be called with
369 * concurrent list_add(), but for better safety against future changes
370 * in the code, we use list_empty_careful() here.
371 */
372 if (!list_empty_careful(&isec->list)) {
373 spin_lock(&sbsec->isec_lock);
374 list_del_init(&isec->list);
375 spin_unlock(&sbsec->isec_lock);
376 }
377}
378
379struct selinux_mnt_opts {
380 const char *fscontext, *context, *rootcontext, *defcontext;
381};
382
383static void selinux_free_mnt_opts(void *mnt_opts)
384{
385 struct selinux_mnt_opts *opts = mnt_opts;
386 kfree(opts->fscontext);
387 kfree(opts->context);
388 kfree(opts->rootcontext);
389 kfree(opts->defcontext);
390 kfree(opts);
391}
392
393enum {
394 Opt_error = -1,
395 Opt_context = 0,
396 Opt_defcontext = 1,
397 Opt_fscontext = 2,
398 Opt_rootcontext = 3,
399 Opt_seclabel = 4,
400};
401
402#define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
403static struct {
404 const char *name;
405 int len;
406 int opt;
407 bool has_arg;
408} tokens[] = {
409 A(context, true),
410 A(fscontext, true),
411 A(defcontext, true),
412 A(rootcontext, true),
413 A(seclabel, false),
414};
415#undef A
416
417static int match_opt_prefix(char *s, int l, char **arg)
418{
419 int i;
420
421 for (i = 0; i < ARRAY_SIZE(tokens); i++) {
422 size_t len = tokens[i].len;
423 if (len > l || memcmp(s, tokens[i].name, len))
424 continue;
425 if (tokens[i].has_arg) {
426 if (len == l || s[len] != '=')
427 continue;
428 *arg = s + len + 1;
429 } else if (len != l)
430 continue;
431 return tokens[i].opt;
432 }
433 return Opt_error;
434}
435
436#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
437
438static int may_context_mount_sb_relabel(u32 sid,
439 struct superblock_security_struct *sbsec,
440 const struct cred *cred)
441{
442 const struct task_security_struct *tsec = selinux_cred(cred);
443 int rc;
444
445 rc = avc_has_perm(&selinux_state,
446 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
447 FILESYSTEM__RELABELFROM, NULL);
448 if (rc)
449 return rc;
450
451 rc = avc_has_perm(&selinux_state,
452 tsec->sid, sid, SECCLASS_FILESYSTEM,
453 FILESYSTEM__RELABELTO, NULL);
454 return rc;
455}
456
457static int may_context_mount_inode_relabel(u32 sid,
458 struct superblock_security_struct *sbsec,
459 const struct cred *cred)
460{
461 const struct task_security_struct *tsec = selinux_cred(cred);
462 int rc;
463 rc = avc_has_perm(&selinux_state,
464 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
465 FILESYSTEM__RELABELFROM, NULL);
466 if (rc)
467 return rc;
468
469 rc = avc_has_perm(&selinux_state,
470 sid, sbsec->sid, SECCLASS_FILESYSTEM,
471 FILESYSTEM__ASSOCIATE, NULL);
472 return rc;
473}
474
475static int selinux_is_genfs_special_handling(struct super_block *sb)
476{
477 /* Special handling. Genfs but also in-core setxattr handler */
478 return !strcmp(sb->s_type->name, "sysfs") ||
479 !strcmp(sb->s_type->name, "pstore") ||
480 !strcmp(sb->s_type->name, "debugfs") ||
481 !strcmp(sb->s_type->name, "tracefs") ||
482 !strcmp(sb->s_type->name, "rootfs") ||
483 (selinux_policycap_cgroupseclabel() &&
484 (!strcmp(sb->s_type->name, "cgroup") ||
485 !strcmp(sb->s_type->name, "cgroup2")));
486}
487
488static int selinux_is_sblabel_mnt(struct super_block *sb)
489{
490 struct superblock_security_struct *sbsec = selinux_superblock(sb);
491
492 /*
493 * IMPORTANT: Double-check logic in this function when adding a new
494 * SECURITY_FS_USE_* definition!
495 */
496 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
497
498 switch (sbsec->behavior) {
499 case SECURITY_FS_USE_XATTR:
500 case SECURITY_FS_USE_TRANS:
501 case SECURITY_FS_USE_TASK:
502 case SECURITY_FS_USE_NATIVE:
503 return 1;
504
505 case SECURITY_FS_USE_GENFS:
506 return selinux_is_genfs_special_handling(sb);
507
508 /* Never allow relabeling on context mounts */
509 case SECURITY_FS_USE_MNTPOINT:
510 case SECURITY_FS_USE_NONE:
511 default:
512 return 0;
513 }
514}
515
516static int sb_check_xattr_support(struct super_block *sb)
517{
518 struct superblock_security_struct *sbsec = sb->s_security;
519 struct dentry *root = sb->s_root;
520 struct inode *root_inode = d_backing_inode(root);
521 u32 sid;
522 int rc;
523
524 /*
525 * Make sure that the xattr handler exists and that no
526 * error other than -ENODATA is returned by getxattr on
527 * the root directory. -ENODATA is ok, as this may be
528 * the first boot of the SELinux kernel before we have
529 * assigned xattr values to the filesystem.
530 */
531 if (!(root_inode->i_opflags & IOP_XATTR)) {
532 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
533 sb->s_id, sb->s_type->name);
534 goto fallback;
535 }
536
537 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
538 if (rc < 0 && rc != -ENODATA) {
539 if (rc == -EOPNOTSUPP) {
540 pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
541 sb->s_id, sb->s_type->name);
542 goto fallback;
543 } else {
544 pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
545 sb->s_id, sb->s_type->name, -rc);
546 return rc;
547 }
548 }
549 return 0;
550
551fallback:
552 /* No xattr support - try to fallback to genfs if possible. */
553 rc = security_genfs_sid(&selinux_state, sb->s_type->name, "/",
554 SECCLASS_DIR, &sid);
555 if (rc)
556 return -EOPNOTSUPP;
557
558 pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
559 sb->s_id, sb->s_type->name);
560 sbsec->behavior = SECURITY_FS_USE_GENFS;
561 sbsec->sid = sid;
562 return 0;
563}
564
565static int sb_finish_set_opts(struct super_block *sb)
566{
567 struct superblock_security_struct *sbsec = selinux_superblock(sb);
568 struct dentry *root = sb->s_root;
569 struct inode *root_inode = d_backing_inode(root);
570 int rc = 0;
571
572 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
573 rc = sb_check_xattr_support(sb);
574 if (rc)
575 return rc;
576 }
577
578 sbsec->flags |= SE_SBINITIALIZED;
579
580 /*
581 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply
582 * leave the flag untouched because sb_clone_mnt_opts might be handing
583 * us a superblock that needs the flag to be cleared.
584 */
585 if (selinux_is_sblabel_mnt(sb))
586 sbsec->flags |= SBLABEL_MNT;
587 else
588 sbsec->flags &= ~SBLABEL_MNT;
589
590 /* Initialize the root inode. */
591 rc = inode_doinit_with_dentry(root_inode, root);
592
593 /* Initialize any other inodes associated with the superblock, e.g.
594 inodes created prior to initial policy load or inodes created
595 during get_sb by a pseudo filesystem that directly
596 populates itself. */
597 spin_lock(&sbsec->isec_lock);
598 while (!list_empty(&sbsec->isec_head)) {
599 struct inode_security_struct *isec =
600 list_first_entry(&sbsec->isec_head,
601 struct inode_security_struct, list);
602 struct inode *inode = isec->inode;
603 list_del_init(&isec->list);
604 spin_unlock(&sbsec->isec_lock);
605 inode = igrab(inode);
606 if (inode) {
607 if (!IS_PRIVATE(inode))
608 inode_doinit_with_dentry(inode, NULL);
609 iput(inode);
610 }
611 spin_lock(&sbsec->isec_lock);
612 }
613 spin_unlock(&sbsec->isec_lock);
614 return rc;
615}
616
617static int bad_option(struct superblock_security_struct *sbsec, char flag,
618 u32 old_sid, u32 new_sid)
619{
620 char mnt_flags = sbsec->flags & SE_MNTMASK;
621
622 /* check if the old mount command had the same options */
623 if (sbsec->flags & SE_SBINITIALIZED)
624 if (!(sbsec->flags & flag) ||
625 (old_sid != new_sid))
626 return 1;
627
628 /* check if we were passed the same options twice,
629 * aka someone passed context=a,context=b
630 */
631 if (!(sbsec->flags & SE_SBINITIALIZED))
632 if (mnt_flags & flag)
633 return 1;
634 return 0;
635}
636
637static int parse_sid(struct super_block *sb, const char *s, u32 *sid)
638{
639 int rc = security_context_str_to_sid(&selinux_state, s,
640 sid, GFP_KERNEL);
641 if (rc)
642 pr_warn("SELinux: security_context_str_to_sid"
643 "(%s) failed for (dev %s, type %s) errno=%d\n",
644 s, sb->s_id, sb->s_type->name, rc);
645 return rc;
646}
647
648/*
649 * Allow filesystems with binary mount data to explicitly set mount point
650 * labeling information.
651 */
652static int selinux_set_mnt_opts(struct super_block *sb,
653 void *mnt_opts,
654 unsigned long kern_flags,
655 unsigned long *set_kern_flags)
656{
657 const struct cred *cred = current_cred();
658 struct superblock_security_struct *sbsec = selinux_superblock(sb);
659 struct dentry *root = sb->s_root;
660 struct selinux_mnt_opts *opts = mnt_opts;
661 struct inode_security_struct *root_isec;
662 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
663 u32 defcontext_sid = 0;
664 int rc = 0;
665
666 mutex_lock(&sbsec->lock);
667
668 if (!selinux_initialized(&selinux_state)) {
669 if (!opts) {
670 /* Defer initialization until selinux_complete_init,
671 after the initial policy is loaded and the security
672 server is ready to handle calls. */
673 goto out;
674 }
675 rc = -EINVAL;
676 pr_warn("SELinux: Unable to set superblock options "
677 "before the security server is initialized\n");
678 goto out;
679 }
680 if (kern_flags && !set_kern_flags) {
681 /* Specifying internal flags without providing a place to
682 * place the results is not allowed */
683 rc = -EINVAL;
684 goto out;
685 }
686
687 /*
688 * Binary mount data FS will come through this function twice. Once
689 * from an explicit call and once from the generic calls from the vfs.
690 * Since the generic VFS calls will not contain any security mount data
691 * we need to skip the double mount verification.
692 *
693 * This does open a hole in which we will not notice if the first
694 * mount using this sb set explict options and a second mount using
695 * this sb does not set any security options. (The first options
696 * will be used for both mounts)
697 */
698 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
699 && !opts)
700 goto out;
701
702 root_isec = backing_inode_security_novalidate(root);
703
704 /*
705 * parse the mount options, check if they are valid sids.
706 * also check if someone is trying to mount the same sb more
707 * than once with different security options.
708 */
709 if (opts) {
710 if (opts->fscontext) {
711 rc = parse_sid(sb, opts->fscontext, &fscontext_sid);
712 if (rc)
713 goto out;
714 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
715 fscontext_sid))
716 goto out_double_mount;
717 sbsec->flags |= FSCONTEXT_MNT;
718 }
719 if (opts->context) {
720 rc = parse_sid(sb, opts->context, &context_sid);
721 if (rc)
722 goto out;
723 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
724 context_sid))
725 goto out_double_mount;
726 sbsec->flags |= CONTEXT_MNT;
727 }
728 if (opts->rootcontext) {
729 rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid);
730 if (rc)
731 goto out;
732 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
733 rootcontext_sid))
734 goto out_double_mount;
735 sbsec->flags |= ROOTCONTEXT_MNT;
736 }
737 if (opts->defcontext) {
738 rc = parse_sid(sb, opts->defcontext, &defcontext_sid);
739 if (rc)
740 goto out;
741 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
742 defcontext_sid))
743 goto out_double_mount;
744 sbsec->flags |= DEFCONTEXT_MNT;
745 }
746 }
747
748 if (sbsec->flags & SE_SBINITIALIZED) {
749 /* previously mounted with options, but not on this attempt? */
750 if ((sbsec->flags & SE_MNTMASK) && !opts)
751 goto out_double_mount;
752 rc = 0;
753 goto out;
754 }
755
756 if (strcmp(sb->s_type->name, "proc") == 0)
757 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
758
759 if (!strcmp(sb->s_type->name, "debugfs") ||
760 !strcmp(sb->s_type->name, "tracefs") ||
761 !strcmp(sb->s_type->name, "binder") ||
762 !strcmp(sb->s_type->name, "bpf") ||
763 !strcmp(sb->s_type->name, "pstore"))
764 sbsec->flags |= SE_SBGENFS;
765
766 if (!strcmp(sb->s_type->name, "sysfs") ||
767 !strcmp(sb->s_type->name, "cgroup") ||
768 !strcmp(sb->s_type->name, "cgroup2"))
769 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
770
771 if (!sbsec->behavior) {
772 /*
773 * Determine the labeling behavior to use for this
774 * filesystem type.
775 */
776 rc = security_fs_use(&selinux_state, sb);
777 if (rc) {
778 pr_warn("%s: security_fs_use(%s) returned %d\n",
779 __func__, sb->s_type->name, rc);
780 goto out;
781 }
782 }
783
784 /*
785 * If this is a user namespace mount and the filesystem type is not
786 * explicitly whitelisted, then no contexts are allowed on the command
787 * line and security labels must be ignored.
788 */
789 if (sb->s_user_ns != &init_user_ns &&
790 strcmp(sb->s_type->name, "tmpfs") &&
791 strcmp(sb->s_type->name, "ramfs") &&
792 strcmp(sb->s_type->name, "devpts") &&
793 strcmp(sb->s_type->name, "overlay")) {
794 if (context_sid || fscontext_sid || rootcontext_sid ||
795 defcontext_sid) {
796 rc = -EACCES;
797 goto out;
798 }
799 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
800 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
801 rc = security_transition_sid(&selinux_state,
802 current_sid(),
803 current_sid(),
804 SECCLASS_FILE, NULL,
805 &sbsec->mntpoint_sid);
806 if (rc)
807 goto out;
808 }
809 goto out_set_opts;
810 }
811
812 /* sets the context of the superblock for the fs being mounted. */
813 if (fscontext_sid) {
814 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
815 if (rc)
816 goto out;
817
818 sbsec->sid = fscontext_sid;
819 }
820
821 /*
822 * Switch to using mount point labeling behavior.
823 * sets the label used on all file below the mountpoint, and will set
824 * the superblock context if not already set.
825 */
826 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
827 sbsec->behavior = SECURITY_FS_USE_NATIVE;
828 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
829 }
830
831 if (context_sid) {
832 if (!fscontext_sid) {
833 rc = may_context_mount_sb_relabel(context_sid, sbsec,
834 cred);
835 if (rc)
836 goto out;
837 sbsec->sid = context_sid;
838 } else {
839 rc = may_context_mount_inode_relabel(context_sid, sbsec,
840 cred);
841 if (rc)
842 goto out;
843 }
844 if (!rootcontext_sid)
845 rootcontext_sid = context_sid;
846
847 sbsec->mntpoint_sid = context_sid;
848 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
849 }
850
851 if (rootcontext_sid) {
852 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
853 cred);
854 if (rc)
855 goto out;
856
857 root_isec->sid = rootcontext_sid;
858 root_isec->initialized = LABEL_INITIALIZED;
859 }
860
861 if (defcontext_sid) {
862 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
863 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
864 rc = -EINVAL;
865 pr_warn("SELinux: defcontext option is "
866 "invalid for this filesystem type\n");
867 goto out;
868 }
869
870 if (defcontext_sid != sbsec->def_sid) {
871 rc = may_context_mount_inode_relabel(defcontext_sid,
872 sbsec, cred);
873 if (rc)
874 goto out;
875 }
876
877 sbsec->def_sid = defcontext_sid;
878 }
879
880out_set_opts:
881 rc = sb_finish_set_opts(sb);
882out:
883 mutex_unlock(&sbsec->lock);
884 return rc;
885out_double_mount:
886 rc = -EINVAL;
887 pr_warn("SELinux: mount invalid. Same superblock, different "
888 "security settings for (dev %s, type %s)\n", sb->s_id,
889 sb->s_type->name);
890 goto out;
891}
892
893static int selinux_cmp_sb_context(const struct super_block *oldsb,
894 const struct super_block *newsb)
895{
896 struct superblock_security_struct *old = selinux_superblock(oldsb);
897 struct superblock_security_struct *new = selinux_superblock(newsb);
898 char oldflags = old->flags & SE_MNTMASK;
899 char newflags = new->flags & SE_MNTMASK;
900
901 if (oldflags != newflags)
902 goto mismatch;
903 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
904 goto mismatch;
905 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
906 goto mismatch;
907 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
908 goto mismatch;
909 if (oldflags & ROOTCONTEXT_MNT) {
910 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
911 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
912 if (oldroot->sid != newroot->sid)
913 goto mismatch;
914 }
915 return 0;
916mismatch:
917 pr_warn("SELinux: mount invalid. Same superblock, "
918 "different security settings for (dev %s, "
919 "type %s)\n", newsb->s_id, newsb->s_type->name);
920 return -EBUSY;
921}
922
923static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
924 struct super_block *newsb,
925 unsigned long kern_flags,
926 unsigned long *set_kern_flags)
927{
928 int rc = 0;
929 const struct superblock_security_struct *oldsbsec =
930 selinux_superblock(oldsb);
931 struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
932
933 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
934 int set_context = (oldsbsec->flags & CONTEXT_MNT);
935 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
936
937 /*
938 * if the parent was able to be mounted it clearly had no special lsm
939 * mount options. thus we can safely deal with this superblock later
940 */
941 if (!selinux_initialized(&selinux_state))
942 return 0;
943
944 /*
945 * Specifying internal flags without providing a place to
946 * place the results is not allowed.
947 */
948 if (kern_flags && !set_kern_flags)
949 return -EINVAL;
950
951 /* how can we clone if the old one wasn't set up?? */
952 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
953
954 /* if fs is reusing a sb, make sure that the contexts match */
955 if (newsbsec->flags & SE_SBINITIALIZED) {
956 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
957 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
958 return selinux_cmp_sb_context(oldsb, newsb);
959 }
960
961 mutex_lock(&newsbsec->lock);
962
963 newsbsec->flags = oldsbsec->flags;
964
965 newsbsec->sid = oldsbsec->sid;
966 newsbsec->def_sid = oldsbsec->def_sid;
967 newsbsec->behavior = oldsbsec->behavior;
968
969 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
970 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
971 rc = security_fs_use(&selinux_state, newsb);
972 if (rc)
973 goto out;
974 }
975
976 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
977 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
978 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
979 }
980
981 if (set_context) {
982 u32 sid = oldsbsec->mntpoint_sid;
983
984 if (!set_fscontext)
985 newsbsec->sid = sid;
986 if (!set_rootcontext) {
987 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
988 newisec->sid = sid;
989 }
990 newsbsec->mntpoint_sid = sid;
991 }
992 if (set_rootcontext) {
993 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
994 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
995
996 newisec->sid = oldisec->sid;
997 }
998
999 sb_finish_set_opts(newsb);
1000out:
1001 mutex_unlock(&newsbsec->lock);
1002 return rc;
1003}
1004
1005static int selinux_add_opt(int token, const char *s, void **mnt_opts)
1006{
1007 struct selinux_mnt_opts *opts = *mnt_opts;
1008
1009 if (token == Opt_seclabel) /* eaten and completely ignored */
1010 return 0;
1011
1012 if (!opts) {
1013 opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
1014 if (!opts)
1015 return -ENOMEM;
1016 *mnt_opts = opts;
1017 }
1018 if (!s)
1019 return -ENOMEM;
1020 switch (token) {
1021 case Opt_context:
1022 if (opts->context || opts->defcontext)
1023 goto Einval;
1024 opts->context = s;
1025 break;
1026 case Opt_fscontext:
1027 if (opts->fscontext)
1028 goto Einval;
1029 opts->fscontext = s;
1030 break;
1031 case Opt_rootcontext:
1032 if (opts->rootcontext)
1033 goto Einval;
1034 opts->rootcontext = s;
1035 break;
1036 case Opt_defcontext:
1037 if (opts->context || opts->defcontext)
1038 goto Einval;
1039 opts->defcontext = s;
1040 break;
1041 }
1042 return 0;
1043Einval:
1044 pr_warn(SEL_MOUNT_FAIL_MSG);
1045 return -EINVAL;
1046}
1047
1048static int selinux_add_mnt_opt(const char *option, const char *val, int len,
1049 void **mnt_opts)
1050{
1051 int token = Opt_error;
1052 int rc, i;
1053
1054 for (i = 0; i < ARRAY_SIZE(tokens); i++) {
1055 if (strcmp(option, tokens[i].name) == 0) {
1056 token = tokens[i].opt;
1057 break;
1058 }
1059 }
1060
1061 if (token == Opt_error)
1062 return -EINVAL;
1063
1064 if (token != Opt_seclabel) {
1065 val = kmemdup_nul(val, len, GFP_KERNEL);
1066 if (!val) {
1067 rc = -ENOMEM;
1068 goto free_opt;
1069 }
1070 }
1071 rc = selinux_add_opt(token, val, mnt_opts);
1072 if (unlikely(rc)) {
1073 kfree(val);
1074 goto free_opt;
1075 }
1076 return rc;
1077
1078free_opt:
1079 if (*mnt_opts) {
1080 selinux_free_mnt_opts(*mnt_opts);
1081 *mnt_opts = NULL;
1082 }
1083 return rc;
1084}
1085
1086static int show_sid(struct seq_file *m, u32 sid)
1087{
1088 char *context = NULL;
1089 u32 len;
1090 int rc;
1091
1092 rc = security_sid_to_context(&selinux_state, sid,
1093 &context, &len);
1094 if (!rc) {
1095 bool has_comma = context && strchr(context, ',');
1096
1097 seq_putc(m, '=');
1098 if (has_comma)
1099 seq_putc(m, '\"');
1100 seq_escape(m, context, "\"\n\\");
1101 if (has_comma)
1102 seq_putc(m, '\"');
1103 }
1104 kfree(context);
1105 return rc;
1106}
1107
1108static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1109{
1110 struct superblock_security_struct *sbsec = selinux_superblock(sb);
1111 int rc;
1112
1113 if (!(sbsec->flags & SE_SBINITIALIZED))
1114 return 0;
1115
1116 if (!selinux_initialized(&selinux_state))
1117 return 0;
1118
1119 if (sbsec->flags & FSCONTEXT_MNT) {
1120 seq_putc(m, ',');
1121 seq_puts(m, FSCONTEXT_STR);
1122 rc = show_sid(m, sbsec->sid);
1123 if (rc)
1124 return rc;
1125 }
1126 if (sbsec->flags & CONTEXT_MNT) {
1127 seq_putc(m, ',');
1128 seq_puts(m, CONTEXT_STR);
1129 rc = show_sid(m, sbsec->mntpoint_sid);
1130 if (rc)
1131 return rc;
1132 }
1133 if (sbsec->flags & DEFCONTEXT_MNT) {
1134 seq_putc(m, ',');
1135 seq_puts(m, DEFCONTEXT_STR);
1136 rc = show_sid(m, sbsec->def_sid);
1137 if (rc)
1138 return rc;
1139 }
1140 if (sbsec->flags & ROOTCONTEXT_MNT) {
1141 struct dentry *root = sb->s_root;
1142 struct inode_security_struct *isec = backing_inode_security(root);
1143 seq_putc(m, ',');
1144 seq_puts(m, ROOTCONTEXT_STR);
1145 rc = show_sid(m, isec->sid);
1146 if (rc)
1147 return rc;
1148 }
1149 if (sbsec->flags & SBLABEL_MNT) {
1150 seq_putc(m, ',');
1151 seq_puts(m, SECLABEL_STR);
1152 }
1153 return 0;
1154}
1155
1156static inline u16 inode_mode_to_security_class(umode_t mode)
1157{
1158 switch (mode & S_IFMT) {
1159 case S_IFSOCK:
1160 return SECCLASS_SOCK_FILE;
1161 case S_IFLNK:
1162 return SECCLASS_LNK_FILE;
1163 case S_IFREG:
1164 return SECCLASS_FILE;
1165 case S_IFBLK:
1166 return SECCLASS_BLK_FILE;
1167 case S_IFDIR:
1168 return SECCLASS_DIR;
1169 case S_IFCHR:
1170 return SECCLASS_CHR_FILE;
1171 case S_IFIFO:
1172 return SECCLASS_FIFO_FILE;
1173
1174 }
1175
1176 return SECCLASS_FILE;
1177}
1178
1179static inline int default_protocol_stream(int protocol)
1180{
1181 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1182 protocol == IPPROTO_MPTCP);
1183}
1184
1185static inline int default_protocol_dgram(int protocol)
1186{
1187 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1188}
1189
1190static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1191{
1192 int extsockclass = selinux_policycap_extsockclass();
1193
1194 switch (family) {
1195 case PF_UNIX:
1196 switch (type) {
1197 case SOCK_STREAM:
1198 case SOCK_SEQPACKET:
1199 return SECCLASS_UNIX_STREAM_SOCKET;
1200 case SOCK_DGRAM:
1201 case SOCK_RAW:
1202 return SECCLASS_UNIX_DGRAM_SOCKET;
1203 }
1204 break;
1205 case PF_INET:
1206 case PF_INET6:
1207 switch (type) {
1208 case SOCK_STREAM:
1209 case SOCK_SEQPACKET:
1210 if (default_protocol_stream(protocol))
1211 return SECCLASS_TCP_SOCKET;
1212 else if (extsockclass && protocol == IPPROTO_SCTP)
1213 return SECCLASS_SCTP_SOCKET;
1214 else
1215 return SECCLASS_RAWIP_SOCKET;
1216 case SOCK_DGRAM:
1217 if (default_protocol_dgram(protocol))
1218 return SECCLASS_UDP_SOCKET;
1219 else if (extsockclass && (protocol == IPPROTO_ICMP ||
1220 protocol == IPPROTO_ICMPV6))
1221 return SECCLASS_ICMP_SOCKET;
1222 else
1223 return SECCLASS_RAWIP_SOCKET;
1224 case SOCK_DCCP:
1225 return SECCLASS_DCCP_SOCKET;
1226 default:
1227 return SECCLASS_RAWIP_SOCKET;
1228 }
1229 break;
1230 case PF_NETLINK:
1231 switch (protocol) {
1232 case NETLINK_ROUTE:
1233 return SECCLASS_NETLINK_ROUTE_SOCKET;
1234 case NETLINK_SOCK_DIAG:
1235 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1236 case NETLINK_NFLOG:
1237 return SECCLASS_NETLINK_NFLOG_SOCKET;
1238 case NETLINK_XFRM:
1239 return SECCLASS_NETLINK_XFRM_SOCKET;
1240 case NETLINK_SELINUX:
1241 return SECCLASS_NETLINK_SELINUX_SOCKET;
1242 case NETLINK_ISCSI:
1243 return SECCLASS_NETLINK_ISCSI_SOCKET;
1244 case NETLINK_AUDIT:
1245 return SECCLASS_NETLINK_AUDIT_SOCKET;
1246 case NETLINK_FIB_LOOKUP:
1247 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1248 case NETLINK_CONNECTOR:
1249 return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1250 case NETLINK_NETFILTER:
1251 return SECCLASS_NETLINK_NETFILTER_SOCKET;
1252 case NETLINK_DNRTMSG:
1253 return SECCLASS_NETLINK_DNRT_SOCKET;
1254 case NETLINK_KOBJECT_UEVENT:
1255 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1256 case NETLINK_GENERIC:
1257 return SECCLASS_NETLINK_GENERIC_SOCKET;
1258 case NETLINK_SCSITRANSPORT:
1259 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1260 case NETLINK_RDMA:
1261 return SECCLASS_NETLINK_RDMA_SOCKET;
1262 case NETLINK_CRYPTO:
1263 return SECCLASS_NETLINK_CRYPTO_SOCKET;
1264 default:
1265 return SECCLASS_NETLINK_SOCKET;
1266 }
1267 case PF_PACKET:
1268 return SECCLASS_PACKET_SOCKET;
1269 case PF_KEY:
1270 return SECCLASS_KEY_SOCKET;
1271 case PF_APPLETALK:
1272 return SECCLASS_APPLETALK_SOCKET;
1273 }
1274
1275 if (extsockclass) {
1276 switch (family) {
1277 case PF_AX25:
1278 return SECCLASS_AX25_SOCKET;
1279 case PF_IPX:
1280 return SECCLASS_IPX_SOCKET;
1281 case PF_NETROM:
1282 return SECCLASS_NETROM_SOCKET;
1283 case PF_ATMPVC:
1284 return SECCLASS_ATMPVC_SOCKET;
1285 case PF_X25:
1286 return SECCLASS_X25_SOCKET;
1287 case PF_ROSE:
1288 return SECCLASS_ROSE_SOCKET;
1289 case PF_DECnet:
1290 return SECCLASS_DECNET_SOCKET;
1291 case PF_ATMSVC:
1292 return SECCLASS_ATMSVC_SOCKET;
1293 case PF_RDS:
1294 return SECCLASS_RDS_SOCKET;
1295 case PF_IRDA:
1296 return SECCLASS_IRDA_SOCKET;
1297 case PF_PPPOX:
1298 return SECCLASS_PPPOX_SOCKET;
1299 case PF_LLC:
1300 return SECCLASS_LLC_SOCKET;
1301 case PF_CAN:
1302 return SECCLASS_CAN_SOCKET;
1303 case PF_TIPC:
1304 return SECCLASS_TIPC_SOCKET;
1305 case PF_BLUETOOTH:
1306 return SECCLASS_BLUETOOTH_SOCKET;
1307 case PF_IUCV:
1308 return SECCLASS_IUCV_SOCKET;
1309 case PF_RXRPC:
1310 return SECCLASS_RXRPC_SOCKET;
1311 case PF_ISDN:
1312 return SECCLASS_ISDN_SOCKET;
1313 case PF_PHONET:
1314 return SECCLASS_PHONET_SOCKET;
1315 case PF_IEEE802154:
1316 return SECCLASS_IEEE802154_SOCKET;
1317 case PF_CAIF:
1318 return SECCLASS_CAIF_SOCKET;
1319 case PF_ALG:
1320 return SECCLASS_ALG_SOCKET;
1321 case PF_NFC:
1322 return SECCLASS_NFC_SOCKET;
1323 case PF_VSOCK:
1324 return SECCLASS_VSOCK_SOCKET;
1325 case PF_KCM:
1326 return SECCLASS_KCM_SOCKET;
1327 case PF_QIPCRTR:
1328 return SECCLASS_QIPCRTR_SOCKET;
1329 case PF_SMC:
1330 return SECCLASS_SMC_SOCKET;
1331 case PF_XDP:
1332 return SECCLASS_XDP_SOCKET;
1333#if PF_MAX > 45
1334#error New address family defined, please update this function.
1335#endif
1336 }
1337 }
1338
1339 return SECCLASS_SOCKET;
1340}
1341
1342static int selinux_genfs_get_sid(struct dentry *dentry,
1343 u16 tclass,
1344 u16 flags,
1345 u32 *sid)
1346{
1347 int rc;
1348 struct super_block *sb = dentry->d_sb;
1349 char *buffer, *path;
1350
1351 buffer = (char *)__get_free_page(GFP_KERNEL);
1352 if (!buffer)
1353 return -ENOMEM;
1354
1355 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1356 if (IS_ERR(path))
1357 rc = PTR_ERR(path);
1358 else {
1359 if (flags & SE_SBPROC) {
1360 /* each process gets a /proc/PID/ entry. Strip off the
1361 * PID part to get a valid selinux labeling.
1362 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1363 while (path[1] >= '0' && path[1] <= '9') {
1364 path[1] = '/';
1365 path++;
1366 }
1367 }
1368 rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1369 path, tclass, sid);
1370 if (rc == -ENOENT) {
1371 /* No match in policy, mark as unlabeled. */
1372 *sid = SECINITSID_UNLABELED;
1373 rc = 0;
1374 }
1375 }
1376 free_page((unsigned long)buffer);
1377 return rc;
1378}
1379
1380static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1381 u32 def_sid, u32 *sid)
1382{
1383#define INITCONTEXTLEN 255
1384 char *context;
1385 unsigned int len;
1386 int rc;
1387
1388 len = INITCONTEXTLEN;
1389 context = kmalloc(len + 1, GFP_NOFS);
1390 if (!context)
1391 return -ENOMEM;
1392
1393 context[len] = '\0';
1394 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1395 if (rc == -ERANGE) {
1396 kfree(context);
1397
1398 /* Need a larger buffer. Query for the right size. */
1399 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1400 if (rc < 0)
1401 return rc;
1402
1403 len = rc;
1404 context = kmalloc(len + 1, GFP_NOFS);
1405 if (!context)
1406 return -ENOMEM;
1407
1408 context[len] = '\0';
1409 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1410 context, len);
1411 }
1412 if (rc < 0) {
1413 kfree(context);
1414 if (rc != -ENODATA) {
1415 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n",
1416 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1417 return rc;
1418 }
1419 *sid = def_sid;
1420 return 0;
1421 }
1422
1423 rc = security_context_to_sid_default(&selinux_state, context, rc, sid,
1424 def_sid, GFP_NOFS);
1425 if (rc) {
1426 char *dev = inode->i_sb->s_id;
1427 unsigned long ino = inode->i_ino;
1428
1429 if (rc == -EINVAL) {
1430 pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s. This indicates you may need to relabel the inode or the filesystem in question.\n",
1431 ino, dev, context);
1432 } else {
1433 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1434 __func__, context, -rc, dev, ino);
1435 }
1436 }
1437 kfree(context);
1438 return 0;
1439}
1440
1441/* The inode's security attributes must be initialized before first use. */
1442static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1443{
1444 struct superblock_security_struct *sbsec = NULL;
1445 struct inode_security_struct *isec = selinux_inode(inode);
1446 u32 task_sid, sid = 0;
1447 u16 sclass;
1448 struct dentry *dentry;
1449 int rc = 0;
1450
1451 if (isec->initialized == LABEL_INITIALIZED)
1452 return 0;
1453
1454 spin_lock(&isec->lock);
1455 if (isec->initialized == LABEL_INITIALIZED)
1456 goto out_unlock;
1457
1458 if (isec->sclass == SECCLASS_FILE)
1459 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1460
1461 sbsec = selinux_superblock(inode->i_sb);
1462 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1463 /* Defer initialization until selinux_complete_init,
1464 after the initial policy is loaded and the security
1465 server is ready to handle calls. */
1466 spin_lock(&sbsec->isec_lock);
1467 if (list_empty(&isec->list))
1468 list_add(&isec->list, &sbsec->isec_head);
1469 spin_unlock(&sbsec->isec_lock);
1470 goto out_unlock;
1471 }
1472
1473 sclass = isec->sclass;
1474 task_sid = isec->task_sid;
1475 sid = isec->sid;
1476 isec->initialized = LABEL_PENDING;
1477 spin_unlock(&isec->lock);
1478
1479 switch (sbsec->behavior) {
1480 case SECURITY_FS_USE_NATIVE:
1481 break;
1482 case SECURITY_FS_USE_XATTR:
1483 if (!(inode->i_opflags & IOP_XATTR)) {
1484 sid = sbsec->def_sid;
1485 break;
1486 }
1487 /* Need a dentry, since the xattr API requires one.
1488 Life would be simpler if we could just pass the inode. */
1489 if (opt_dentry) {
1490 /* Called from d_instantiate or d_splice_alias. */
1491 dentry = dget(opt_dentry);
1492 } else {
1493 /*
1494 * Called from selinux_complete_init, try to find a dentry.
1495 * Some filesystems really want a connected one, so try
1496 * that first. We could split SECURITY_FS_USE_XATTR in
1497 * two, depending upon that...
1498 */
1499 dentry = d_find_alias(inode);
1500 if (!dentry)
1501 dentry = d_find_any_alias(inode);
1502 }
1503 if (!dentry) {
1504 /*
1505 * this is can be hit on boot when a file is accessed
1506 * before the policy is loaded. When we load policy we
1507 * may find inodes that have no dentry on the
1508 * sbsec->isec_head list. No reason to complain as these
1509 * will get fixed up the next time we go through
1510 * inode_doinit with a dentry, before these inodes could
1511 * be used again by userspace.
1512 */
1513 goto out_invalid;
1514 }
1515
1516 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1517 &sid);
1518 dput(dentry);
1519 if (rc)
1520 goto out;
1521 break;
1522 case SECURITY_FS_USE_TASK:
1523 sid = task_sid;
1524 break;
1525 case SECURITY_FS_USE_TRANS:
1526 /* Default to the fs SID. */
1527 sid = sbsec->sid;
1528
1529 /* Try to obtain a transition SID. */
1530 rc = security_transition_sid(&selinux_state, task_sid, sid,
1531 sclass, NULL, &sid);
1532 if (rc)
1533 goto out;
1534 break;
1535 case SECURITY_FS_USE_MNTPOINT:
1536 sid = sbsec->mntpoint_sid;
1537 break;
1538 default:
1539 /* Default to the fs superblock SID. */
1540 sid = sbsec->sid;
1541
1542 if ((sbsec->flags & SE_SBGENFS) &&
1543 (!S_ISLNK(inode->i_mode) ||
1544 selinux_policycap_genfs_seclabel_symlinks())) {
1545 /* We must have a dentry to determine the label on
1546 * procfs inodes */
1547 if (opt_dentry) {
1548 /* Called from d_instantiate or
1549 * d_splice_alias. */
1550 dentry = dget(opt_dentry);
1551 } else {
1552 /* Called from selinux_complete_init, try to
1553 * find a dentry. Some filesystems really want
1554 * a connected one, so try that first.
1555 */
1556 dentry = d_find_alias(inode);
1557 if (!dentry)
1558 dentry = d_find_any_alias(inode);
1559 }
1560 /*
1561 * This can be hit on boot when a file is accessed
1562 * before the policy is loaded. When we load policy we
1563 * may find inodes that have no dentry on the
1564 * sbsec->isec_head list. No reason to complain as
1565 * these will get fixed up the next time we go through
1566 * inode_doinit() with a dentry, before these inodes
1567 * could be used again by userspace.
1568 */
1569 if (!dentry)
1570 goto out_invalid;
1571 rc = selinux_genfs_get_sid(dentry, sclass,
1572 sbsec->flags, &sid);
1573 if (rc) {
1574 dput(dentry);
1575 goto out;
1576 }
1577
1578 if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1579 (inode->i_opflags & IOP_XATTR)) {
1580 rc = inode_doinit_use_xattr(inode, dentry,
1581 sid, &sid);
1582 if (rc) {
1583 dput(dentry);
1584 goto out;
1585 }
1586 }
1587 dput(dentry);
1588 }
1589 break;
1590 }
1591
1592out:
1593 spin_lock(&isec->lock);
1594 if (isec->initialized == LABEL_PENDING) {
1595 if (rc) {
1596 isec->initialized = LABEL_INVALID;
1597 goto out_unlock;
1598 }
1599 isec->initialized = LABEL_INITIALIZED;
1600 isec->sid = sid;
1601 }
1602
1603out_unlock:
1604 spin_unlock(&isec->lock);
1605 return rc;
1606
1607out_invalid:
1608 spin_lock(&isec->lock);
1609 if (isec->initialized == LABEL_PENDING) {
1610 isec->initialized = LABEL_INVALID;
1611 isec->sid = sid;
1612 }
1613 spin_unlock(&isec->lock);
1614 return 0;
1615}
1616
1617/* Convert a Linux signal to an access vector. */
1618static inline u32 signal_to_av(int sig)
1619{
1620 u32 perm = 0;
1621
1622 switch (sig) {
1623 case SIGCHLD:
1624 /* Commonly granted from child to parent. */
1625 perm = PROCESS__SIGCHLD;
1626 break;
1627 case SIGKILL:
1628 /* Cannot be caught or ignored */
1629 perm = PROCESS__SIGKILL;
1630 break;
1631 case SIGSTOP:
1632 /* Cannot be caught or ignored */
1633 perm = PROCESS__SIGSTOP;
1634 break;
1635 default:
1636 /* All other signals. */
1637 perm = PROCESS__SIGNAL;
1638 break;
1639 }
1640
1641 return perm;
1642}
1643
1644#if CAP_LAST_CAP > 63
1645#error Fix SELinux to handle capabilities > 63.
1646#endif
1647
1648/* Check whether a task is allowed to use a capability. */
1649static int cred_has_capability(const struct cred *cred,
1650 int cap, unsigned int opts, bool initns)
1651{
1652 struct common_audit_data ad;
1653 struct av_decision avd;
1654 u16 sclass;
1655 u32 sid = cred_sid(cred);
1656 u32 av = CAP_TO_MASK(cap);
1657 int rc;
1658
1659 ad.type = LSM_AUDIT_DATA_CAP;
1660 ad.u.cap = cap;
1661
1662 switch (CAP_TO_INDEX(cap)) {
1663 case 0:
1664 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1665 break;
1666 case 1:
1667 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1668 break;
1669 default:
1670 pr_err("SELinux: out of range capability %d\n", cap);
1671 BUG();
1672 return -EINVAL;
1673 }
1674
1675 rc = avc_has_perm_noaudit(&selinux_state,
1676 sid, sid, sclass, av, 0, &avd);
1677 if (!(opts & CAP_OPT_NOAUDIT)) {
1678 int rc2 = avc_audit(&selinux_state,
1679 sid, sid, sclass, av, &avd, rc, &ad);
1680 if (rc2)
1681 return rc2;
1682 }
1683 return rc;
1684}
1685
1686/* Check whether a task has a particular permission to an inode.
1687 The 'adp' parameter is optional and allows other audit
1688 data to be passed (e.g. the dentry). */
1689static int inode_has_perm(const struct cred *cred,
1690 struct inode *inode,
1691 u32 perms,
1692 struct common_audit_data *adp)
1693{
1694 struct inode_security_struct *isec;
1695 u32 sid;
1696
1697 validate_creds(cred);
1698
1699 if (unlikely(IS_PRIVATE(inode)))
1700 return 0;
1701
1702 sid = cred_sid(cred);
1703 isec = selinux_inode(inode);
1704
1705 return avc_has_perm(&selinux_state,
1706 sid, isec->sid, isec->sclass, perms, adp);
1707}
1708
1709/* Same as inode_has_perm, but pass explicit audit data containing
1710 the dentry to help the auditing code to more easily generate the
1711 pathname if needed. */
1712static inline int dentry_has_perm(const struct cred *cred,
1713 struct dentry *dentry,
1714 u32 av)
1715{
1716 struct inode *inode = d_backing_inode(dentry);
1717 struct common_audit_data ad;
1718
1719 ad.type = LSM_AUDIT_DATA_DENTRY;
1720 ad.u.dentry = dentry;
1721 __inode_security_revalidate(inode, dentry, true);
1722 return inode_has_perm(cred, inode, av, &ad);
1723}
1724
1725/* Same as inode_has_perm, but pass explicit audit data containing
1726 the path to help the auditing code to more easily generate the
1727 pathname if needed. */
1728static inline int path_has_perm(const struct cred *cred,
1729 const struct path *path,
1730 u32 av)
1731{
1732 struct inode *inode = d_backing_inode(path->dentry);
1733 struct common_audit_data ad;
1734
1735 ad.type = LSM_AUDIT_DATA_PATH;
1736 ad.u.path = *path;
1737 __inode_security_revalidate(inode, path->dentry, true);
1738 return inode_has_perm(cred, inode, av, &ad);
1739}
1740
1741/* Same as path_has_perm, but uses the inode from the file struct. */
1742static inline int file_path_has_perm(const struct cred *cred,
1743 struct file *file,
1744 u32 av)
1745{
1746 struct common_audit_data ad;
1747
1748 ad.type = LSM_AUDIT_DATA_FILE;
1749 ad.u.file = file;
1750 return inode_has_perm(cred, file_inode(file), av, &ad);
1751}
1752
1753#ifdef CONFIG_BPF_SYSCALL
1754static int bpf_fd_pass(struct file *file, u32 sid);
1755#endif
1756
1757/* Check whether a task can use an open file descriptor to
1758 access an inode in a given way. Check access to the
1759 descriptor itself, and then use dentry_has_perm to
1760 check a particular permission to the file.
1761 Access to the descriptor is implicitly granted if it
1762 has the same SID as the process. If av is zero, then
1763 access to the file is not checked, e.g. for cases
1764 where only the descriptor is affected like seek. */
1765static int file_has_perm(const struct cred *cred,
1766 struct file *file,
1767 u32 av)
1768{
1769 struct file_security_struct *fsec = selinux_file(file);
1770 struct inode *inode = file_inode(file);
1771 struct common_audit_data ad;
1772 u32 sid = cred_sid(cred);
1773 int rc;
1774
1775 ad.type = LSM_AUDIT_DATA_FILE;
1776 ad.u.file = file;
1777
1778 if (sid != fsec->sid) {
1779 rc = avc_has_perm(&selinux_state,
1780 sid, fsec->sid,
1781 SECCLASS_FD,
1782 FD__USE,
1783 &ad);
1784 if (rc)
1785 goto out;
1786 }
1787
1788#ifdef CONFIG_BPF_SYSCALL
1789 rc = bpf_fd_pass(file, cred_sid(cred));
1790 if (rc)
1791 return rc;
1792#endif
1793
1794 /* av is zero if only checking access to the descriptor. */
1795 rc = 0;
1796 if (av)
1797 rc = inode_has_perm(cred, inode, av, &ad);
1798
1799out:
1800 return rc;
1801}
1802
1803/*
1804 * Determine the label for an inode that might be unioned.
1805 */
1806static int
1807selinux_determine_inode_label(const struct task_security_struct *tsec,
1808 struct inode *dir,
1809 const struct qstr *name, u16 tclass,
1810 u32 *_new_isid)
1811{
1812 const struct superblock_security_struct *sbsec =
1813 selinux_superblock(dir->i_sb);
1814
1815 if ((sbsec->flags & SE_SBINITIALIZED) &&
1816 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1817 *_new_isid = sbsec->mntpoint_sid;
1818 } else if ((sbsec->flags & SBLABEL_MNT) &&
1819 tsec->create_sid) {
1820 *_new_isid = tsec->create_sid;
1821 } else {
1822 const struct inode_security_struct *dsec = inode_security(dir);
1823 return security_transition_sid(&selinux_state, tsec->sid,
1824 dsec->sid, tclass,
1825 name, _new_isid);
1826 }
1827
1828 return 0;
1829}
1830
1831/* Check whether a task can create a file. */
1832static int may_create(struct inode *dir,
1833 struct dentry *dentry,
1834 u16 tclass)
1835{
1836 const struct task_security_struct *tsec = selinux_cred(current_cred());
1837 struct inode_security_struct *dsec;
1838 struct superblock_security_struct *sbsec;
1839 u32 sid, newsid;
1840 struct common_audit_data ad;
1841 int rc;
1842
1843 dsec = inode_security(dir);
1844 sbsec = selinux_superblock(dir->i_sb);
1845
1846 sid = tsec->sid;
1847
1848 ad.type = LSM_AUDIT_DATA_DENTRY;
1849 ad.u.dentry = dentry;
1850
1851 rc = avc_has_perm(&selinux_state,
1852 sid, dsec->sid, SECCLASS_DIR,
1853 DIR__ADD_NAME | DIR__SEARCH,
1854 &ad);
1855 if (rc)
1856 return rc;
1857
1858 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1859 &newsid);
1860 if (rc)
1861 return rc;
1862
1863 rc = avc_has_perm(&selinux_state,
1864 sid, newsid, tclass, FILE__CREATE, &ad);
1865 if (rc)
1866 return rc;
1867
1868 return avc_has_perm(&selinux_state,
1869 newsid, sbsec->sid,
1870 SECCLASS_FILESYSTEM,
1871 FILESYSTEM__ASSOCIATE, &ad);
1872}
1873
1874#define MAY_LINK 0
1875#define MAY_UNLINK 1
1876#define MAY_RMDIR 2
1877
1878/* Check whether a task can link, unlink, or rmdir a file/directory. */
1879static int may_link(struct inode *dir,
1880 struct dentry *dentry,
1881 int kind)
1882
1883{
1884 struct inode_security_struct *dsec, *isec;
1885 struct common_audit_data ad;
1886 u32 sid = current_sid();
1887 u32 av;
1888 int rc;
1889
1890 dsec = inode_security(dir);
1891 isec = backing_inode_security(dentry);
1892
1893 ad.type = LSM_AUDIT_DATA_DENTRY;
1894 ad.u.dentry = dentry;
1895
1896 av = DIR__SEARCH;
1897 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1898 rc = avc_has_perm(&selinux_state,
1899 sid, dsec->sid, SECCLASS_DIR, av, &ad);
1900 if (rc)
1901 return rc;
1902
1903 switch (kind) {
1904 case MAY_LINK:
1905 av = FILE__LINK;
1906 break;
1907 case MAY_UNLINK:
1908 av = FILE__UNLINK;
1909 break;
1910 case MAY_RMDIR:
1911 av = DIR__RMDIR;
1912 break;
1913 default:
1914 pr_warn("SELinux: %s: unrecognized kind %d\n",
1915 __func__, kind);
1916 return 0;
1917 }
1918
1919 rc = avc_has_perm(&selinux_state,
1920 sid, isec->sid, isec->sclass, av, &ad);
1921 return rc;
1922}
1923
1924static inline int may_rename(struct inode *old_dir,
1925 struct dentry *old_dentry,
1926 struct inode *new_dir,
1927 struct dentry *new_dentry)
1928{
1929 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1930 struct common_audit_data ad;
1931 u32 sid = current_sid();
1932 u32 av;
1933 int old_is_dir, new_is_dir;
1934 int rc;
1935
1936 old_dsec = inode_security(old_dir);
1937 old_isec = backing_inode_security(old_dentry);
1938 old_is_dir = d_is_dir(old_dentry);
1939 new_dsec = inode_security(new_dir);
1940
1941 ad.type = LSM_AUDIT_DATA_DENTRY;
1942
1943 ad.u.dentry = old_dentry;
1944 rc = avc_has_perm(&selinux_state,
1945 sid, old_dsec->sid, SECCLASS_DIR,
1946 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1947 if (rc)
1948 return rc;
1949 rc = avc_has_perm(&selinux_state,
1950 sid, old_isec->sid,
1951 old_isec->sclass, FILE__RENAME, &ad);
1952 if (rc)
1953 return rc;
1954 if (old_is_dir && new_dir != old_dir) {
1955 rc = avc_has_perm(&selinux_state,
1956 sid, old_isec->sid,
1957 old_isec->sclass, DIR__REPARENT, &ad);
1958 if (rc)
1959 return rc;
1960 }
1961
1962 ad.u.dentry = new_dentry;
1963 av = DIR__ADD_NAME | DIR__SEARCH;
1964 if (d_is_positive(new_dentry))
1965 av |= DIR__REMOVE_NAME;
1966 rc = avc_has_perm(&selinux_state,
1967 sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1968 if (rc)
1969 return rc;
1970 if (d_is_positive(new_dentry)) {
1971 new_isec = backing_inode_security(new_dentry);
1972 new_is_dir = d_is_dir(new_dentry);
1973 rc = avc_has_perm(&selinux_state,
1974 sid, new_isec->sid,
1975 new_isec->sclass,
1976 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1977 if (rc)
1978 return rc;
1979 }
1980
1981 return 0;
1982}
1983
1984/* Check whether a task can perform a filesystem operation. */
1985static int superblock_has_perm(const struct cred *cred,
1986 struct super_block *sb,
1987 u32 perms,
1988 struct common_audit_data *ad)
1989{
1990 struct superblock_security_struct *sbsec;
1991 u32 sid = cred_sid(cred);
1992
1993 sbsec = selinux_superblock(sb);
1994 return avc_has_perm(&selinux_state,
1995 sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1996}
1997
1998/* Convert a Linux mode and permission mask to an access vector. */
1999static inline u32 file_mask_to_av(int mode, int mask)
2000{
2001 u32 av = 0;
2002
2003 if (!S_ISDIR(mode)) {
2004 if (mask & MAY_EXEC)
2005 av |= FILE__EXECUTE;
2006 if (mask & MAY_READ)
2007 av |= FILE__READ;
2008
2009 if (mask & MAY_APPEND)
2010 av |= FILE__APPEND;
2011 else if (mask & MAY_WRITE)
2012 av |= FILE__WRITE;
2013
2014 } else {
2015 if (mask & MAY_EXEC)
2016 av |= DIR__SEARCH;
2017 if (mask & MAY_WRITE)
2018 av |= DIR__WRITE;
2019 if (mask & MAY_READ)
2020 av |= DIR__READ;
2021 }
2022
2023 return av;
2024}
2025
2026/* Convert a Linux file to an access vector. */
2027static inline u32 file_to_av(struct file *file)
2028{
2029 u32 av = 0;
2030
2031 if (file->f_mode & FMODE_READ)
2032 av |= FILE__READ;
2033 if (file->f_mode & FMODE_WRITE) {
2034 if (file->f_flags & O_APPEND)
2035 av |= FILE__APPEND;
2036 else
2037 av |= FILE__WRITE;
2038 }
2039 if (!av) {
2040 /*
2041 * Special file opened with flags 3 for ioctl-only use.
2042 */
2043 av = FILE__IOCTL;
2044 }
2045
2046 return av;
2047}
2048
2049/*
2050 * Convert a file to an access vector and include the correct
2051 * open permission.
2052 */
2053static inline u32 open_file_to_av(struct file *file)
2054{
2055 u32 av = file_to_av(file);
2056 struct inode *inode = file_inode(file);
2057
2058 if (selinux_policycap_openperm() &&
2059 inode->i_sb->s_magic != SOCKFS_MAGIC)
2060 av |= FILE__OPEN;
2061
2062 return av;
2063}
2064
2065/* Hook functions begin here. */
2066
2067static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2068{
2069 return avc_has_perm(&selinux_state,
2070 current_sid(), task_sid_binder(mgr), SECCLASS_BINDER,
2071 BINDER__SET_CONTEXT_MGR, NULL);
2072}
2073
2074static int selinux_binder_transaction(struct task_struct *from,
2075 struct task_struct *to)
2076{
2077 u32 mysid = current_sid();
2078 u32 fromsid = task_sid_binder(from);
2079 int rc;
2080
2081 if (mysid != fromsid) {
2082 rc = avc_has_perm(&selinux_state,
2083 mysid, fromsid, SECCLASS_BINDER,
2084 BINDER__IMPERSONATE, NULL);
2085 if (rc)
2086 return rc;
2087 }
2088
2089 return avc_has_perm(&selinux_state, fromsid, task_sid_binder(to),
2090 SECCLASS_BINDER, BINDER__CALL, NULL);
2091}
2092
2093static int selinux_binder_transfer_binder(struct task_struct *from,
2094 struct task_struct *to)
2095{
2096 return avc_has_perm(&selinux_state,
2097 task_sid_binder(from), task_sid_binder(to),
2098 SECCLASS_BINDER, BINDER__TRANSFER,
2099 NULL);
2100}
2101
2102static int selinux_binder_transfer_file(struct task_struct *from,
2103 struct task_struct *to,
2104 struct file *file)
2105{
2106 u32 sid = task_sid_binder(to);
2107 struct file_security_struct *fsec = selinux_file(file);
2108 struct dentry *dentry = file->f_path.dentry;
2109 struct inode_security_struct *isec;
2110 struct common_audit_data ad;
2111 int rc;
2112
2113 ad.type = LSM_AUDIT_DATA_PATH;
2114 ad.u.path = file->f_path;
2115
2116 if (sid != fsec->sid) {
2117 rc = avc_has_perm(&selinux_state,
2118 sid, fsec->sid,
2119 SECCLASS_FD,
2120 FD__USE,
2121 &ad);
2122 if (rc)
2123 return rc;
2124 }
2125
2126#ifdef CONFIG_BPF_SYSCALL
2127 rc = bpf_fd_pass(file, sid);
2128 if (rc)
2129 return rc;
2130#endif
2131
2132 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2133 return 0;
2134
2135 isec = backing_inode_security(dentry);
2136 return avc_has_perm(&selinux_state,
2137 sid, isec->sid, isec->sclass, file_to_av(file),
2138 &ad);
2139}
2140
2141static int selinux_ptrace_access_check(struct task_struct *child,
2142 unsigned int mode)
2143{
2144 u32 sid = current_sid();
2145 u32 csid = task_sid_obj(child);
2146
2147 if (mode & PTRACE_MODE_READ)
2148 return avc_has_perm(&selinux_state,
2149 sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2150
2151 return avc_has_perm(&selinux_state,
2152 sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2153}
2154
2155static int selinux_ptrace_traceme(struct task_struct *parent)
2156{
2157 return avc_has_perm(&selinux_state,
2158 task_sid_obj(parent), task_sid_obj(current),
2159 SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2160}
2161
2162static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2163 kernel_cap_t *inheritable, kernel_cap_t *permitted)
2164{
2165 return avc_has_perm(&selinux_state,
2166 current_sid(), task_sid_obj(target), SECCLASS_PROCESS,
2167 PROCESS__GETCAP, NULL);
2168}
2169
2170static int selinux_capset(struct cred *new, const struct cred *old,
2171 const kernel_cap_t *effective,
2172 const kernel_cap_t *inheritable,
2173 const kernel_cap_t *permitted)
2174{
2175 return avc_has_perm(&selinux_state,
2176 cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2177 PROCESS__SETCAP, NULL);
2178}
2179
2180/*
2181 * (This comment used to live with the selinux_task_setuid hook,
2182 * which was removed).
2183 *
2184 * Since setuid only affects the current process, and since the SELinux
2185 * controls are not based on the Linux identity attributes, SELinux does not
2186 * need to control this operation. However, SELinux does control the use of
2187 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2188 */
2189
2190static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2191 int cap, unsigned int opts)
2192{
2193 return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2194}
2195
2196static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2197{
2198 const struct cred *cred = current_cred();
2199 int rc = 0;
2200
2201 if (!sb)
2202 return 0;
2203
2204 switch (cmds) {
2205 case Q_SYNC:
2206 case Q_QUOTAON:
2207 case Q_QUOTAOFF:
2208 case Q_SETINFO:
2209 case Q_SETQUOTA:
2210 case Q_XQUOTAOFF:
2211 case Q_XQUOTAON:
2212 case Q_XSETQLIM:
2213 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2214 break;
2215 case Q_GETFMT:
2216 case Q_GETINFO:
2217 case Q_GETQUOTA:
2218 case Q_XGETQUOTA:
2219 case Q_XGETQSTAT:
2220 case Q_XGETQSTATV:
2221 case Q_XGETNEXTQUOTA:
2222 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2223 break;
2224 default:
2225 rc = 0; /* let the kernel handle invalid cmds */
2226 break;
2227 }
2228 return rc;
2229}
2230
2231static int selinux_quota_on(struct dentry *dentry)
2232{
2233 const struct cred *cred = current_cred();
2234
2235 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2236}
2237
2238static int selinux_syslog(int type)
2239{
2240 switch (type) {
2241 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2242 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2243 return avc_has_perm(&selinux_state,
2244 current_sid(), SECINITSID_KERNEL,
2245 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2246 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2247 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2248 /* Set level of messages printed to console */
2249 case SYSLOG_ACTION_CONSOLE_LEVEL:
2250 return avc_has_perm(&selinux_state,
2251 current_sid(), SECINITSID_KERNEL,
2252 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2253 NULL);
2254 }
2255 /* All other syslog types */
2256 return avc_has_perm(&selinux_state,
2257 current_sid(), SECINITSID_KERNEL,
2258 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2259}
2260
2261/*
2262 * Check that a process has enough memory to allocate a new virtual
2263 * mapping. 0 means there is enough memory for the allocation to
2264 * succeed and -ENOMEM implies there is not.
2265 *
2266 * Do not audit the selinux permission check, as this is applied to all
2267 * processes that allocate mappings.
2268 */
2269static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2270{
2271 int rc, cap_sys_admin = 0;
2272
2273 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2274 CAP_OPT_NOAUDIT, true);
2275 if (rc == 0)
2276 cap_sys_admin = 1;
2277
2278 return cap_sys_admin;
2279}
2280
2281/* binprm security operations */
2282
2283static u32 ptrace_parent_sid(void)
2284{
2285 u32 sid = 0;
2286 struct task_struct *tracer;
2287
2288 rcu_read_lock();
2289 tracer = ptrace_parent(current);
2290 if (tracer)
2291 sid = task_sid_obj(tracer);
2292 rcu_read_unlock();
2293
2294 return sid;
2295}
2296
2297static int check_nnp_nosuid(const struct linux_binprm *bprm,
2298 const struct task_security_struct *old_tsec,
2299 const struct task_security_struct *new_tsec)
2300{
2301 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2302 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2303 int rc;
2304 u32 av;
2305
2306 if (!nnp && !nosuid)
2307 return 0; /* neither NNP nor nosuid */
2308
2309 if (new_tsec->sid == old_tsec->sid)
2310 return 0; /* No change in credentials */
2311
2312 /*
2313 * If the policy enables the nnp_nosuid_transition policy capability,
2314 * then we permit transitions under NNP or nosuid if the
2315 * policy allows the corresponding permission between
2316 * the old and new contexts.
2317 */
2318 if (selinux_policycap_nnp_nosuid_transition()) {
2319 av = 0;
2320 if (nnp)
2321 av |= PROCESS2__NNP_TRANSITION;
2322 if (nosuid)
2323 av |= PROCESS2__NOSUID_TRANSITION;
2324 rc = avc_has_perm(&selinux_state,
2325 old_tsec->sid, new_tsec->sid,
2326 SECCLASS_PROCESS2, av, NULL);
2327 if (!rc)
2328 return 0;
2329 }
2330
2331 /*
2332 * We also permit NNP or nosuid transitions to bounded SIDs,
2333 * i.e. SIDs that are guaranteed to only be allowed a subset
2334 * of the permissions of the current SID.
2335 */
2336 rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2337 new_tsec->sid);
2338 if (!rc)
2339 return 0;
2340
2341 /*
2342 * On failure, preserve the errno values for NNP vs nosuid.
2343 * NNP: Operation not permitted for caller.
2344 * nosuid: Permission denied to file.
2345 */
2346 if (nnp)
2347 return -EPERM;
2348 return -EACCES;
2349}
2350
2351static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2352{
2353 const struct task_security_struct *old_tsec;
2354 struct task_security_struct *new_tsec;
2355 struct inode_security_struct *isec;
2356 struct common_audit_data ad;
2357 struct inode *inode = file_inode(bprm->file);
2358 int rc;
2359
2360 /* SELinux context only depends on initial program or script and not
2361 * the script interpreter */
2362
2363 old_tsec = selinux_cred(current_cred());
2364 new_tsec = selinux_cred(bprm->cred);
2365 isec = inode_security(inode);
2366
2367 /* Default to the current task SID. */
2368 new_tsec->sid = old_tsec->sid;
2369 new_tsec->osid = old_tsec->sid;
2370
2371 /* Reset fs, key, and sock SIDs on execve. */
2372 new_tsec->create_sid = 0;
2373 new_tsec->keycreate_sid = 0;
2374 new_tsec->sockcreate_sid = 0;
2375
2376 if (old_tsec->exec_sid) {
2377 new_tsec->sid = old_tsec->exec_sid;
2378 /* Reset exec SID on execve. */
2379 new_tsec->exec_sid = 0;
2380
2381 /* Fail on NNP or nosuid if not an allowed transition. */
2382 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2383 if (rc)
2384 return rc;
2385 } else {
2386 /* Check for a default transition on this program. */
2387 rc = security_transition_sid(&selinux_state, old_tsec->sid,
2388 isec->sid, SECCLASS_PROCESS, NULL,
2389 &new_tsec->sid);
2390 if (rc)
2391 return rc;
2392
2393 /*
2394 * Fallback to old SID on NNP or nosuid if not an allowed
2395 * transition.
2396 */
2397 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2398 if (rc)
2399 new_tsec->sid = old_tsec->sid;
2400 }
2401
2402 ad.type = LSM_AUDIT_DATA_FILE;
2403 ad.u.file = bprm->file;
2404
2405 if (new_tsec->sid == old_tsec->sid) {
2406 rc = avc_has_perm(&selinux_state,
2407 old_tsec->sid, isec->sid,
2408 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2409 if (rc)
2410 return rc;
2411 } else {
2412 /* Check permissions for the transition. */
2413 rc = avc_has_perm(&selinux_state,
2414 old_tsec->sid, new_tsec->sid,
2415 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2416 if (rc)
2417 return rc;
2418
2419 rc = avc_has_perm(&selinux_state,
2420 new_tsec->sid, isec->sid,
2421 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2422 if (rc)
2423 return rc;
2424
2425 /* Check for shared state */
2426 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2427 rc = avc_has_perm(&selinux_state,
2428 old_tsec->sid, new_tsec->sid,
2429 SECCLASS_PROCESS, PROCESS__SHARE,
2430 NULL);
2431 if (rc)
2432 return -EPERM;
2433 }
2434
2435 /* Make sure that anyone attempting to ptrace over a task that
2436 * changes its SID has the appropriate permit */
2437 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2438 u32 ptsid = ptrace_parent_sid();
2439 if (ptsid != 0) {
2440 rc = avc_has_perm(&selinux_state,
2441 ptsid, new_tsec->sid,
2442 SECCLASS_PROCESS,
2443 PROCESS__PTRACE, NULL);
2444 if (rc)
2445 return -EPERM;
2446 }
2447 }
2448
2449 /* Clear any possibly unsafe personality bits on exec: */
2450 bprm->per_clear |= PER_CLEAR_ON_SETID;
2451
2452 /* Enable secure mode for SIDs transitions unless
2453 the noatsecure permission is granted between
2454 the two SIDs, i.e. ahp returns 0. */
2455 rc = avc_has_perm(&selinux_state,
2456 old_tsec->sid, new_tsec->sid,
2457 SECCLASS_PROCESS, PROCESS__NOATSECURE,
2458 NULL);
2459 bprm->secureexec |= !!rc;
2460 }
2461
2462 return 0;
2463}
2464
2465static int match_file(const void *p, struct file *file, unsigned fd)
2466{
2467 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2468}
2469
2470/* Derived from fs/exec.c:flush_old_files. */
2471static inline void flush_unauthorized_files(const struct cred *cred,
2472 struct files_struct *files)
2473{
2474 struct file *file, *devnull = NULL;
2475 struct tty_struct *tty;
2476 int drop_tty = 0;
2477 unsigned n;
2478
2479 tty = get_current_tty();
2480 if (tty) {
2481 spin_lock(&tty->files_lock);
2482 if (!list_empty(&tty->tty_files)) {
2483 struct tty_file_private *file_priv;
2484
2485 /* Revalidate access to controlling tty.
2486 Use file_path_has_perm on the tty path directly
2487 rather than using file_has_perm, as this particular
2488 open file may belong to another process and we are
2489 only interested in the inode-based check here. */
2490 file_priv = list_first_entry(&tty->tty_files,
2491 struct tty_file_private, list);
2492 file = file_priv->file;
2493 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2494 drop_tty = 1;
2495 }
2496 spin_unlock(&tty->files_lock);
2497 tty_kref_put(tty);
2498 }
2499 /* Reset controlling tty. */
2500 if (drop_tty)
2501 no_tty();
2502
2503 /* Revalidate access to inherited open files. */
2504 n = iterate_fd(files, 0, match_file, cred);
2505 if (!n) /* none found? */
2506 return;
2507
2508 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2509 if (IS_ERR(devnull))
2510 devnull = NULL;
2511 /* replace all the matching ones with this */
2512 do {
2513 replace_fd(n - 1, devnull, 0);
2514 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2515 if (devnull)
2516 fput(devnull);
2517}
2518
2519/*
2520 * Prepare a process for imminent new credential changes due to exec
2521 */
2522static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2523{
2524 struct task_security_struct *new_tsec;
2525 struct rlimit *rlim, *initrlim;
2526 int rc, i;
2527
2528 new_tsec = selinux_cred(bprm->cred);
2529 if (new_tsec->sid == new_tsec->osid)
2530 return;
2531
2532 /* Close files for which the new task SID is not authorized. */
2533 flush_unauthorized_files(bprm->cred, current->files);
2534
2535 /* Always clear parent death signal on SID transitions. */
2536 current->pdeath_signal = 0;
2537
2538 /* Check whether the new SID can inherit resource limits from the old
2539 * SID. If not, reset all soft limits to the lower of the current
2540 * task's hard limit and the init task's soft limit.
2541 *
2542 * Note that the setting of hard limits (even to lower them) can be
2543 * controlled by the setrlimit check. The inclusion of the init task's
2544 * soft limit into the computation is to avoid resetting soft limits
2545 * higher than the default soft limit for cases where the default is
2546 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2547 */
2548 rc = avc_has_perm(&selinux_state,
2549 new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2550 PROCESS__RLIMITINH, NULL);
2551 if (rc) {
2552 /* protect against do_prlimit() */
2553 task_lock(current);
2554 for (i = 0; i < RLIM_NLIMITS; i++) {
2555 rlim = current->signal->rlim + i;
2556 initrlim = init_task.signal->rlim + i;
2557 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2558 }
2559 task_unlock(current);
2560 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2561 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2562 }
2563}
2564
2565/*
2566 * Clean up the process immediately after the installation of new credentials
2567 * due to exec
2568 */
2569static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2570{
2571 const struct task_security_struct *tsec = selinux_cred(current_cred());
2572 u32 osid, sid;
2573 int rc;
2574
2575 osid = tsec->osid;
2576 sid = tsec->sid;
2577
2578 if (sid == osid)
2579 return;
2580
2581 /* Check whether the new SID can inherit signal state from the old SID.
2582 * If not, clear itimers to avoid subsequent signal generation and
2583 * flush and unblock signals.
2584 *
2585 * This must occur _after_ the task SID has been updated so that any
2586 * kill done after the flush will be checked against the new SID.
2587 */
2588 rc = avc_has_perm(&selinux_state,
2589 osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2590 if (rc) {
2591 clear_itimer();
2592
2593 spin_lock_irq(¤t->sighand->siglock);
2594 if (!fatal_signal_pending(current)) {
2595 flush_sigqueue(¤t->pending);
2596 flush_sigqueue(¤t->signal->shared_pending);
2597 flush_signal_handlers(current, 1);
2598 sigemptyset(¤t->blocked);
2599 recalc_sigpending();
2600 }
2601 spin_unlock_irq(¤t->sighand->siglock);
2602 }
2603
2604 /* Wake up the parent if it is waiting so that it can recheck
2605 * wait permission to the new task SID. */
2606 read_lock(&tasklist_lock);
2607 __wake_up_parent(current, current->real_parent);
2608 read_unlock(&tasklist_lock);
2609}
2610
2611/* superblock security operations */
2612
2613static int selinux_sb_alloc_security(struct super_block *sb)
2614{
2615 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2616
2617 mutex_init(&sbsec->lock);
2618 INIT_LIST_HEAD(&sbsec->isec_head);
2619 spin_lock_init(&sbsec->isec_lock);
2620 sbsec->sid = SECINITSID_UNLABELED;
2621 sbsec->def_sid = SECINITSID_FILE;
2622 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2623
2624 return 0;
2625}
2626
2627static inline int opt_len(const char *s)
2628{
2629 bool open_quote = false;
2630 int len;
2631 char c;
2632
2633 for (len = 0; (c = s[len]) != '\0'; len++) {
2634 if (c == '"')
2635 open_quote = !open_quote;
2636 if (c == ',' && !open_quote)
2637 break;
2638 }
2639 return len;
2640}
2641
2642static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2643{
2644 char *from = options;
2645 char *to = options;
2646 bool first = true;
2647 int rc;
2648
2649 while (1) {
2650 int len = opt_len(from);
2651 int token;
2652 char *arg = NULL;
2653
2654 token = match_opt_prefix(from, len, &arg);
2655
2656 if (token != Opt_error) {
2657 char *p, *q;
2658
2659 /* strip quotes */
2660 if (arg) {
2661 for (p = q = arg; p < from + len; p++) {
2662 char c = *p;
2663 if (c != '"')
2664 *q++ = c;
2665 }
2666 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2667 if (!arg) {
2668 rc = -ENOMEM;
2669 goto free_opt;
2670 }
2671 }
2672 rc = selinux_add_opt(token, arg, mnt_opts);
2673 if (unlikely(rc)) {
2674 kfree(arg);
2675 goto free_opt;
2676 }
2677 } else {
2678 if (!first) { // copy with preceding comma
2679 from--;
2680 len++;
2681 }
2682 if (to != from)
2683 memmove(to, from, len);
2684 to += len;
2685 first = false;
2686 }
2687 if (!from[len])
2688 break;
2689 from += len + 1;
2690 }
2691 *to = '\0';
2692 return 0;
2693
2694free_opt:
2695 if (*mnt_opts) {
2696 selinux_free_mnt_opts(*mnt_opts);
2697 *mnt_opts = NULL;
2698 }
2699 return rc;
2700}
2701
2702static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
2703{
2704 struct selinux_mnt_opts *opts = mnt_opts;
2705 struct superblock_security_struct *sbsec = sb->s_security;
2706 u32 sid;
2707 int rc;
2708
2709 /*
2710 * Superblock not initialized (i.e. no options) - reject if any
2711 * options specified, otherwise accept.
2712 */
2713 if (!(sbsec->flags & SE_SBINITIALIZED))
2714 return opts ? 1 : 0;
2715
2716 /*
2717 * Superblock initialized and no options specified - reject if
2718 * superblock has any options set, otherwise accept.
2719 */
2720 if (!opts)
2721 return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2722
2723 if (opts->fscontext) {
2724 rc = parse_sid(sb, opts->fscontext, &sid);
2725 if (rc)
2726 return 1;
2727 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2728 return 1;
2729 }
2730 if (opts->context) {
2731 rc = parse_sid(sb, opts->context, &sid);
2732 if (rc)
2733 return 1;
2734 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2735 return 1;
2736 }
2737 if (opts->rootcontext) {
2738 struct inode_security_struct *root_isec;
2739
2740 root_isec = backing_inode_security(sb->s_root);
2741 rc = parse_sid(sb, opts->rootcontext, &sid);
2742 if (rc)
2743 return 1;
2744 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2745 return 1;
2746 }
2747 if (opts->defcontext) {
2748 rc = parse_sid(sb, opts->defcontext, &sid);
2749 if (rc)
2750 return 1;
2751 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2752 return 1;
2753 }
2754 return 0;
2755}
2756
2757static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2758{
2759 struct selinux_mnt_opts *opts = mnt_opts;
2760 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2761 u32 sid;
2762 int rc;
2763
2764 if (!(sbsec->flags & SE_SBINITIALIZED))
2765 return 0;
2766
2767 if (!opts)
2768 return 0;
2769
2770 if (opts->fscontext) {
2771 rc = parse_sid(sb, opts->fscontext, &sid);
2772 if (rc)
2773 return rc;
2774 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2775 goto out_bad_option;
2776 }
2777 if (opts->context) {
2778 rc = parse_sid(sb, opts->context, &sid);
2779 if (rc)
2780 return rc;
2781 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2782 goto out_bad_option;
2783 }
2784 if (opts->rootcontext) {
2785 struct inode_security_struct *root_isec;
2786 root_isec = backing_inode_security(sb->s_root);
2787 rc = parse_sid(sb, opts->rootcontext, &sid);
2788 if (rc)
2789 return rc;
2790 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2791 goto out_bad_option;
2792 }
2793 if (opts->defcontext) {
2794 rc = parse_sid(sb, opts->defcontext, &sid);
2795 if (rc)
2796 return rc;
2797 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2798 goto out_bad_option;
2799 }
2800 return 0;
2801
2802out_bad_option:
2803 pr_warn("SELinux: unable to change security options "
2804 "during remount (dev %s, type=%s)\n", sb->s_id,
2805 sb->s_type->name);
2806 return -EINVAL;
2807}
2808
2809static int selinux_sb_kern_mount(struct super_block *sb)
2810{
2811 const struct cred *cred = current_cred();
2812 struct common_audit_data ad;
2813
2814 ad.type = LSM_AUDIT_DATA_DENTRY;
2815 ad.u.dentry = sb->s_root;
2816 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2817}
2818
2819static int selinux_sb_statfs(struct dentry *dentry)
2820{
2821 const struct cred *cred = current_cred();
2822 struct common_audit_data ad;
2823
2824 ad.type = LSM_AUDIT_DATA_DENTRY;
2825 ad.u.dentry = dentry->d_sb->s_root;
2826 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2827}
2828
2829static int selinux_mount(const char *dev_name,
2830 const struct path *path,
2831 const char *type,
2832 unsigned long flags,
2833 void *data)
2834{
2835 const struct cred *cred = current_cred();
2836
2837 if (flags & MS_REMOUNT)
2838 return superblock_has_perm(cred, path->dentry->d_sb,
2839 FILESYSTEM__REMOUNT, NULL);
2840 else
2841 return path_has_perm(cred, path, FILE__MOUNTON);
2842}
2843
2844static int selinux_move_mount(const struct path *from_path,
2845 const struct path *to_path)
2846{
2847 const struct cred *cred = current_cred();
2848
2849 return path_has_perm(cred, to_path, FILE__MOUNTON);
2850}
2851
2852static int selinux_umount(struct vfsmount *mnt, int flags)
2853{
2854 const struct cred *cred = current_cred();
2855
2856 return superblock_has_perm(cred, mnt->mnt_sb,
2857 FILESYSTEM__UNMOUNT, NULL);
2858}
2859
2860static int selinux_fs_context_dup(struct fs_context *fc,
2861 struct fs_context *src_fc)
2862{
2863 const struct selinux_mnt_opts *src = src_fc->security;
2864 struct selinux_mnt_opts *opts;
2865
2866 if (!src)
2867 return 0;
2868
2869 fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
2870 if (!fc->security)
2871 return -ENOMEM;
2872
2873 opts = fc->security;
2874
2875 if (src->fscontext) {
2876 opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL);
2877 if (!opts->fscontext)
2878 return -ENOMEM;
2879 }
2880 if (src->context) {
2881 opts->context = kstrdup(src->context, GFP_KERNEL);
2882 if (!opts->context)
2883 return -ENOMEM;
2884 }
2885 if (src->rootcontext) {
2886 opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL);
2887 if (!opts->rootcontext)
2888 return -ENOMEM;
2889 }
2890 if (src->defcontext) {
2891 opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL);
2892 if (!opts->defcontext)
2893 return -ENOMEM;
2894 }
2895 return 0;
2896}
2897
2898static const struct fs_parameter_spec selinux_fs_parameters[] = {
2899 fsparam_string(CONTEXT_STR, Opt_context),
2900 fsparam_string(DEFCONTEXT_STR, Opt_defcontext),
2901 fsparam_string(FSCONTEXT_STR, Opt_fscontext),
2902 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2903 fsparam_flag (SECLABEL_STR, Opt_seclabel),
2904 {}
2905};
2906
2907static int selinux_fs_context_parse_param(struct fs_context *fc,
2908 struct fs_parameter *param)
2909{
2910 struct fs_parse_result result;
2911 int opt, rc;
2912
2913 opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2914 if (opt < 0)
2915 return opt;
2916
2917 rc = selinux_add_opt(opt, param->string, &fc->security);
2918 if (!rc) {
2919 param->string = NULL;
2920 rc = 1;
2921 }
2922 return rc;
2923}
2924
2925/* inode security operations */
2926
2927static int selinux_inode_alloc_security(struct inode *inode)
2928{
2929 struct inode_security_struct *isec = selinux_inode(inode);
2930 u32 sid = current_sid();
2931
2932 spin_lock_init(&isec->lock);
2933 INIT_LIST_HEAD(&isec->list);
2934 isec->inode = inode;
2935 isec->sid = SECINITSID_UNLABELED;
2936 isec->sclass = SECCLASS_FILE;
2937 isec->task_sid = sid;
2938 isec->initialized = LABEL_INVALID;
2939
2940 return 0;
2941}
2942
2943static void selinux_inode_free_security(struct inode *inode)
2944{
2945 inode_free_security(inode);
2946}
2947
2948static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2949 const struct qstr *name, void **ctx,
2950 u32 *ctxlen)
2951{
2952 u32 newsid;
2953 int rc;
2954
2955 rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2956 d_inode(dentry->d_parent), name,
2957 inode_mode_to_security_class(mode),
2958 &newsid);
2959 if (rc)
2960 return rc;
2961
2962 return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
2963 ctxlen);
2964}
2965
2966static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2967 struct qstr *name,
2968 const struct cred *old,
2969 struct cred *new)
2970{
2971 u32 newsid;
2972 int rc;
2973 struct task_security_struct *tsec;
2974
2975 rc = selinux_determine_inode_label(selinux_cred(old),
2976 d_inode(dentry->d_parent), name,
2977 inode_mode_to_security_class(mode),
2978 &newsid);
2979 if (rc)
2980 return rc;
2981
2982 tsec = selinux_cred(new);
2983 tsec->create_sid = newsid;
2984 return 0;
2985}
2986
2987static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2988 const struct qstr *qstr,
2989 const char **name,
2990 void **value, size_t *len)
2991{
2992 const struct task_security_struct *tsec = selinux_cred(current_cred());
2993 struct superblock_security_struct *sbsec;
2994 u32 newsid, clen;
2995 int rc;
2996 char *context;
2997
2998 sbsec = selinux_superblock(dir->i_sb);
2999
3000 newsid = tsec->create_sid;
3001
3002 rc = selinux_determine_inode_label(tsec, dir, qstr,
3003 inode_mode_to_security_class(inode->i_mode),
3004 &newsid);
3005 if (rc)
3006 return rc;
3007
3008 /* Possibly defer initialization to selinux_complete_init. */
3009 if (sbsec->flags & SE_SBINITIALIZED) {
3010 struct inode_security_struct *isec = selinux_inode(inode);
3011 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3012 isec->sid = newsid;
3013 isec->initialized = LABEL_INITIALIZED;
3014 }
3015
3016 if (!selinux_initialized(&selinux_state) ||
3017 !(sbsec->flags & SBLABEL_MNT))
3018 return -EOPNOTSUPP;
3019
3020 if (name)
3021 *name = XATTR_SELINUX_SUFFIX;
3022
3023 if (value && len) {
3024 rc = security_sid_to_context_force(&selinux_state, newsid,
3025 &context, &clen);
3026 if (rc)
3027 return rc;
3028 *value = context;
3029 *len = clen;
3030 }
3031
3032 return 0;
3033}
3034
3035static int selinux_inode_init_security_anon(struct inode *inode,
3036 const struct qstr *name,
3037 const struct inode *context_inode)
3038{
3039 const struct task_security_struct *tsec = selinux_cred(current_cred());
3040 struct common_audit_data ad;
3041 struct inode_security_struct *isec;
3042 int rc;
3043
3044 if (unlikely(!selinux_initialized(&selinux_state)))
3045 return 0;
3046
3047 isec = selinux_inode(inode);
3048
3049 /*
3050 * We only get here once per ephemeral inode. The inode has
3051 * been initialized via inode_alloc_security but is otherwise
3052 * untouched.
3053 */
3054
3055 if (context_inode) {
3056 struct inode_security_struct *context_isec =
3057 selinux_inode(context_inode);
3058 if (context_isec->initialized != LABEL_INITIALIZED) {
3059 pr_err("SELinux: context_inode is not initialized");
3060 return -EACCES;
3061 }
3062
3063 isec->sclass = context_isec->sclass;
3064 isec->sid = context_isec->sid;
3065 } else {
3066 isec->sclass = SECCLASS_ANON_INODE;
3067 rc = security_transition_sid(
3068 &selinux_state, tsec->sid, tsec->sid,
3069 isec->sclass, name, &isec->sid);
3070 if (rc)
3071 return rc;
3072 }
3073
3074 isec->initialized = LABEL_INITIALIZED;
3075 /*
3076 * Now that we've initialized security, check whether we're
3077 * allowed to actually create this type of anonymous inode.
3078 */
3079
3080 ad.type = LSM_AUDIT_DATA_INODE;
3081 ad.u.inode = inode;
3082
3083 return avc_has_perm(&selinux_state,
3084 tsec->sid,
3085 isec->sid,
3086 isec->sclass,
3087 FILE__CREATE,
3088 &ad);
3089}
3090
3091static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3092{
3093 return may_create(dir, dentry, SECCLASS_FILE);
3094}
3095
3096static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3097{
3098 return may_link(dir, old_dentry, MAY_LINK);
3099}
3100
3101static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3102{
3103 return may_link(dir, dentry, MAY_UNLINK);
3104}
3105
3106static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3107{
3108 return may_create(dir, dentry, SECCLASS_LNK_FILE);
3109}
3110
3111static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3112{
3113 return may_create(dir, dentry, SECCLASS_DIR);
3114}
3115
3116static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3117{
3118 return may_link(dir, dentry, MAY_RMDIR);
3119}
3120
3121static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3122{
3123 return may_create(dir, dentry, inode_mode_to_security_class(mode));
3124}
3125
3126static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3127 struct inode *new_inode, struct dentry *new_dentry)
3128{
3129 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3130}
3131
3132static int selinux_inode_readlink(struct dentry *dentry)
3133{
3134 const struct cred *cred = current_cred();
3135
3136 return dentry_has_perm(cred, dentry, FILE__READ);
3137}
3138
3139static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3140 bool rcu)
3141{
3142 const struct cred *cred = current_cred();
3143 struct common_audit_data ad;
3144 struct inode_security_struct *isec;
3145 u32 sid;
3146
3147 validate_creds(cred);
3148
3149 ad.type = LSM_AUDIT_DATA_DENTRY;
3150 ad.u.dentry = dentry;
3151 sid = cred_sid(cred);
3152 isec = inode_security_rcu(inode, rcu);
3153 if (IS_ERR(isec))
3154 return PTR_ERR(isec);
3155
3156 return avc_has_perm(&selinux_state,
3157 sid, isec->sid, isec->sclass, FILE__READ, &ad);
3158}
3159
3160static noinline int audit_inode_permission(struct inode *inode,
3161 u32 perms, u32 audited, u32 denied,
3162 int result)
3163{
3164 struct common_audit_data ad;
3165 struct inode_security_struct *isec = selinux_inode(inode);
3166
3167 ad.type = LSM_AUDIT_DATA_INODE;
3168 ad.u.inode = inode;
3169
3170 return slow_avc_audit(&selinux_state,
3171 current_sid(), isec->sid, isec->sclass, perms,
3172 audited, denied, result, &ad);
3173}
3174
3175static int selinux_inode_permission(struct inode *inode, int mask)
3176{
3177 const struct cred *cred = current_cred();
3178 u32 perms;
3179 bool from_access;
3180 bool no_block = mask & MAY_NOT_BLOCK;
3181 struct inode_security_struct *isec;
3182 u32 sid;
3183 struct av_decision avd;
3184 int rc, rc2;
3185 u32 audited, denied;
3186
3187 from_access = mask & MAY_ACCESS;
3188 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3189
3190 /* No permission to check. Existence test. */
3191 if (!mask)
3192 return 0;
3193
3194 validate_creds(cred);
3195
3196 if (unlikely(IS_PRIVATE(inode)))
3197 return 0;
3198
3199 perms = file_mask_to_av(inode->i_mode, mask);
3200
3201 sid = cred_sid(cred);
3202 isec = inode_security_rcu(inode, no_block);
3203 if (IS_ERR(isec))
3204 return PTR_ERR(isec);
3205
3206 rc = avc_has_perm_noaudit(&selinux_state,
3207 sid, isec->sid, isec->sclass, perms, 0,
3208 &avd);
3209 audited = avc_audit_required(perms, &avd, rc,
3210 from_access ? FILE__AUDIT_ACCESS : 0,
3211 &denied);
3212 if (likely(!audited))
3213 return rc;
3214
3215 rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3216 if (rc2)
3217 return rc2;
3218 return rc;
3219}
3220
3221static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3222{
3223 const struct cred *cred = current_cred();
3224 struct inode *inode = d_backing_inode(dentry);
3225 unsigned int ia_valid = iattr->ia_valid;
3226 __u32 av = FILE__WRITE;
3227
3228 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3229 if (ia_valid & ATTR_FORCE) {
3230 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3231 ATTR_FORCE);
3232 if (!ia_valid)
3233 return 0;
3234 }
3235
3236 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3237 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3238 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3239
3240 if (selinux_policycap_openperm() &&
3241 inode->i_sb->s_magic != SOCKFS_MAGIC &&
3242 (ia_valid & ATTR_SIZE) &&
3243 !(ia_valid & ATTR_FILE))
3244 av |= FILE__OPEN;
3245
3246 return dentry_has_perm(cred, dentry, av);
3247}
3248
3249static int selinux_inode_getattr(const struct path *path)
3250{
3251 return path_has_perm(current_cred(), path, FILE__GETATTR);
3252}
3253
3254static bool has_cap_mac_admin(bool audit)
3255{
3256 const struct cred *cred = current_cred();
3257 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3258
3259 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3260 return false;
3261 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3262 return false;
3263 return true;
3264}
3265
3266static int selinux_inode_setxattr(struct user_namespace *mnt_userns,
3267 struct dentry *dentry, const char *name,
3268 const void *value, size_t size, int flags)
3269{
3270 struct inode *inode = d_backing_inode(dentry);
3271 struct inode_security_struct *isec;
3272 struct superblock_security_struct *sbsec;
3273 struct common_audit_data ad;
3274 u32 newsid, sid = current_sid();
3275 int rc = 0;
3276
3277 if (strcmp(name, XATTR_NAME_SELINUX)) {
3278 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3279 if (rc)
3280 return rc;
3281
3282 /* Not an attribute we recognize, so just check the
3283 ordinary setattr permission. */
3284 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3285 }
3286
3287 if (!selinux_initialized(&selinux_state))
3288 return (inode_owner_or_capable(mnt_userns, inode) ? 0 : -EPERM);
3289
3290 sbsec = selinux_superblock(inode->i_sb);
3291 if (!(sbsec->flags & SBLABEL_MNT))
3292 return -EOPNOTSUPP;
3293
3294 if (!inode_owner_or_capable(mnt_userns, inode))
3295 return -EPERM;
3296
3297 ad.type = LSM_AUDIT_DATA_DENTRY;
3298 ad.u.dentry = dentry;
3299
3300 isec = backing_inode_security(dentry);
3301 rc = avc_has_perm(&selinux_state,
3302 sid, isec->sid, isec->sclass,
3303 FILE__RELABELFROM, &ad);
3304 if (rc)
3305 return rc;
3306
3307 rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3308 GFP_KERNEL);
3309 if (rc == -EINVAL) {
3310 if (!has_cap_mac_admin(true)) {
3311 struct audit_buffer *ab;
3312 size_t audit_size;
3313
3314 /* We strip a nul only if it is at the end, otherwise the
3315 * context contains a nul and we should audit that */
3316 if (value) {
3317 const char *str = value;
3318
3319 if (str[size - 1] == '\0')
3320 audit_size = size - 1;
3321 else
3322 audit_size = size;
3323 } else {
3324 audit_size = 0;
3325 }
3326 ab = audit_log_start(audit_context(),
3327 GFP_ATOMIC, AUDIT_SELINUX_ERR);
3328 audit_log_format(ab, "op=setxattr invalid_context=");
3329 audit_log_n_untrustedstring(ab, value, audit_size);
3330 audit_log_end(ab);
3331
3332 return rc;
3333 }
3334 rc = security_context_to_sid_force(&selinux_state, value,
3335 size, &newsid);
3336 }
3337 if (rc)
3338 return rc;
3339
3340 rc = avc_has_perm(&selinux_state,
3341 sid, newsid, isec->sclass,
3342 FILE__RELABELTO, &ad);
3343 if (rc)
3344 return rc;
3345
3346 rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3347 sid, isec->sclass);
3348 if (rc)
3349 return rc;
3350
3351 return avc_has_perm(&selinux_state,
3352 newsid,
3353 sbsec->sid,
3354 SECCLASS_FILESYSTEM,
3355 FILESYSTEM__ASSOCIATE,
3356 &ad);
3357}
3358
3359static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3360 const void *value, size_t size,
3361 int flags)
3362{
3363 struct inode *inode = d_backing_inode(dentry);
3364 struct inode_security_struct *isec;
3365 u32 newsid;
3366 int rc;
3367
3368 if (strcmp(name, XATTR_NAME_SELINUX)) {
3369 /* Not an attribute we recognize, so nothing to do. */
3370 return;
3371 }
3372
3373 if (!selinux_initialized(&selinux_state)) {
3374 /* If we haven't even been initialized, then we can't validate
3375 * against a policy, so leave the label as invalid. It may
3376 * resolve to a valid label on the next revalidation try if
3377 * we've since initialized.
3378 */
3379 return;
3380 }
3381
3382 rc = security_context_to_sid_force(&selinux_state, value, size,
3383 &newsid);
3384 if (rc) {
3385 pr_err("SELinux: unable to map context to SID"
3386 "for (%s, %lu), rc=%d\n",
3387 inode->i_sb->s_id, inode->i_ino, -rc);
3388 return;
3389 }
3390
3391 isec = backing_inode_security(dentry);
3392 spin_lock(&isec->lock);
3393 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3394 isec->sid = newsid;
3395 isec->initialized = LABEL_INITIALIZED;
3396 spin_unlock(&isec->lock);
3397
3398 return;
3399}
3400
3401static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3402{
3403 const struct cred *cred = current_cred();
3404
3405 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3406}
3407
3408static int selinux_inode_listxattr(struct dentry *dentry)
3409{
3410 const struct cred *cred = current_cred();
3411
3412 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3413}
3414
3415static int selinux_inode_removexattr(struct user_namespace *mnt_userns,
3416 struct dentry *dentry, const char *name)
3417{
3418 if (strcmp(name, XATTR_NAME_SELINUX)) {
3419 int rc = cap_inode_removexattr(mnt_userns, dentry, name);
3420 if (rc)
3421 return rc;
3422
3423 /* Not an attribute we recognize, so just check the
3424 ordinary setattr permission. */
3425 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3426 }
3427
3428 if (!selinux_initialized(&selinux_state))
3429 return 0;
3430
3431 /* No one is allowed to remove a SELinux security label.
3432 You can change the label, but all data must be labeled. */
3433 return -EACCES;
3434}
3435
3436static int selinux_path_notify(const struct path *path, u64 mask,
3437 unsigned int obj_type)
3438{
3439 int ret;
3440 u32 perm;
3441
3442 struct common_audit_data ad;
3443
3444 ad.type = LSM_AUDIT_DATA_PATH;
3445 ad.u.path = *path;
3446
3447 /*
3448 * Set permission needed based on the type of mark being set.
3449 * Performs an additional check for sb watches.
3450 */
3451 switch (obj_type) {
3452 case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3453 perm = FILE__WATCH_MOUNT;
3454 break;
3455 case FSNOTIFY_OBJ_TYPE_SB:
3456 perm = FILE__WATCH_SB;
3457 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3458 FILESYSTEM__WATCH, &ad);
3459 if (ret)
3460 return ret;
3461 break;
3462 case FSNOTIFY_OBJ_TYPE_INODE:
3463 perm = FILE__WATCH;
3464 break;
3465 default:
3466 return -EINVAL;
3467 }
3468
3469 /* blocking watches require the file:watch_with_perm permission */
3470 if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3471 perm |= FILE__WATCH_WITH_PERM;
3472
3473 /* watches on read-like events need the file:watch_reads permission */
3474 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3475 perm |= FILE__WATCH_READS;
3476
3477 return path_has_perm(current_cred(), path, perm);
3478}
3479
3480/*
3481 * Copy the inode security context value to the user.
3482 *
3483 * Permission check is handled by selinux_inode_getxattr hook.
3484 */
3485static int selinux_inode_getsecurity(struct user_namespace *mnt_userns,
3486 struct inode *inode, const char *name,
3487 void **buffer, bool alloc)
3488{
3489 u32 size;
3490 int error;
3491 char *context = NULL;
3492 struct inode_security_struct *isec;
3493
3494 /*
3495 * If we're not initialized yet, then we can't validate contexts, so
3496 * just let vfs_getxattr fall back to using the on-disk xattr.
3497 */
3498 if (!selinux_initialized(&selinux_state) ||
3499 strcmp(name, XATTR_SELINUX_SUFFIX))
3500 return -EOPNOTSUPP;
3501
3502 /*
3503 * If the caller has CAP_MAC_ADMIN, then get the raw context
3504 * value even if it is not defined by current policy; otherwise,
3505 * use the in-core value under current policy.
3506 * Use the non-auditing forms of the permission checks since
3507 * getxattr may be called by unprivileged processes commonly
3508 * and lack of permission just means that we fall back to the
3509 * in-core context value, not a denial.
3510 */
3511 isec = inode_security(inode);
3512 if (has_cap_mac_admin(false))
3513 error = security_sid_to_context_force(&selinux_state,
3514 isec->sid, &context,
3515 &size);
3516 else
3517 error = security_sid_to_context(&selinux_state, isec->sid,
3518 &context, &size);
3519 if (error)
3520 return error;
3521 error = size;
3522 if (alloc) {
3523 *buffer = context;
3524 goto out_nofree;
3525 }
3526 kfree(context);
3527out_nofree:
3528 return error;
3529}
3530
3531static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3532 const void *value, size_t size, int flags)
3533{
3534 struct inode_security_struct *isec = inode_security_novalidate(inode);
3535 struct superblock_security_struct *sbsec;
3536 u32 newsid;
3537 int rc;
3538
3539 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3540 return -EOPNOTSUPP;
3541
3542 sbsec = selinux_superblock(inode->i_sb);
3543 if (!(sbsec->flags & SBLABEL_MNT))
3544 return -EOPNOTSUPP;
3545
3546 if (!value || !size)
3547 return -EACCES;
3548
3549 rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3550 GFP_KERNEL);
3551 if (rc)
3552 return rc;
3553
3554 spin_lock(&isec->lock);
3555 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3556 isec->sid = newsid;
3557 isec->initialized = LABEL_INITIALIZED;
3558 spin_unlock(&isec->lock);
3559 return 0;
3560}
3561
3562static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3563{
3564 const int len = sizeof(XATTR_NAME_SELINUX);
3565
3566 if (!selinux_initialized(&selinux_state))
3567 return 0;
3568
3569 if (buffer && len <= buffer_size)
3570 memcpy(buffer, XATTR_NAME_SELINUX, len);
3571 return len;
3572}
3573
3574static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3575{
3576 struct inode_security_struct *isec = inode_security_novalidate(inode);
3577 *secid = isec->sid;
3578}
3579
3580static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3581{
3582 u32 sid;
3583 struct task_security_struct *tsec;
3584 struct cred *new_creds = *new;
3585
3586 if (new_creds == NULL) {
3587 new_creds = prepare_creds();
3588 if (!new_creds)
3589 return -ENOMEM;
3590 }
3591
3592 tsec = selinux_cred(new_creds);
3593 /* Get label from overlay inode and set it in create_sid */
3594 selinux_inode_getsecid(d_inode(src), &sid);
3595 tsec->create_sid = sid;
3596 *new = new_creds;
3597 return 0;
3598}
3599
3600static int selinux_inode_copy_up_xattr(const char *name)
3601{
3602 /* The copy_up hook above sets the initial context on an inode, but we
3603 * don't then want to overwrite it by blindly copying all the lower
3604 * xattrs up. Instead, we have to filter out SELinux-related xattrs.
3605 */
3606 if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3607 return 1; /* Discard */
3608 /*
3609 * Any other attribute apart from SELINUX is not claimed, supported
3610 * by selinux.
3611 */
3612 return -EOPNOTSUPP;
3613}
3614
3615/* kernfs node operations */
3616
3617static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3618 struct kernfs_node *kn)
3619{
3620 const struct task_security_struct *tsec = selinux_cred(current_cred());
3621 u32 parent_sid, newsid, clen;
3622 int rc;
3623 char *context;
3624
3625 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3626 if (rc == -ENODATA)
3627 return 0;
3628 else if (rc < 0)
3629 return rc;
3630
3631 clen = (u32)rc;
3632 context = kmalloc(clen, GFP_KERNEL);
3633 if (!context)
3634 return -ENOMEM;
3635
3636 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3637 if (rc < 0) {
3638 kfree(context);
3639 return rc;
3640 }
3641
3642 rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid,
3643 GFP_KERNEL);
3644 kfree(context);
3645 if (rc)
3646 return rc;
3647
3648 if (tsec->create_sid) {
3649 newsid = tsec->create_sid;
3650 } else {
3651 u16 secclass = inode_mode_to_security_class(kn->mode);
3652 struct qstr q;
3653
3654 q.name = kn->name;
3655 q.hash_len = hashlen_string(kn_dir, kn->name);
3656
3657 rc = security_transition_sid(&selinux_state, tsec->sid,
3658 parent_sid, secclass, &q,
3659 &newsid);
3660 if (rc)
3661 return rc;
3662 }
3663
3664 rc = security_sid_to_context_force(&selinux_state, newsid,
3665 &context, &clen);
3666 if (rc)
3667 return rc;
3668
3669 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3670 XATTR_CREATE);
3671 kfree(context);
3672 return rc;
3673}
3674
3675
3676/* file security operations */
3677
3678static int selinux_revalidate_file_permission(struct file *file, int mask)
3679{
3680 const struct cred *cred = current_cred();
3681 struct inode *inode = file_inode(file);
3682
3683 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3684 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3685 mask |= MAY_APPEND;
3686
3687 return file_has_perm(cred, file,
3688 file_mask_to_av(inode->i_mode, mask));
3689}
3690
3691static int selinux_file_permission(struct file *file, int mask)
3692{
3693 struct inode *inode = file_inode(file);
3694 struct file_security_struct *fsec = selinux_file(file);
3695 struct inode_security_struct *isec;
3696 u32 sid = current_sid();
3697
3698 if (!mask)
3699 /* No permission to check. Existence test. */
3700 return 0;
3701
3702 isec = inode_security(inode);
3703 if (sid == fsec->sid && fsec->isid == isec->sid &&
3704 fsec->pseqno == avc_policy_seqno(&selinux_state))
3705 /* No change since file_open check. */
3706 return 0;
3707
3708 return selinux_revalidate_file_permission(file, mask);
3709}
3710
3711static int selinux_file_alloc_security(struct file *file)
3712{
3713 struct file_security_struct *fsec = selinux_file(file);
3714 u32 sid = current_sid();
3715
3716 fsec->sid = sid;
3717 fsec->fown_sid = sid;
3718
3719 return 0;
3720}
3721
3722/*
3723 * Check whether a task has the ioctl permission and cmd
3724 * operation to an inode.
3725 */
3726static int ioctl_has_perm(const struct cred *cred, struct file *file,
3727 u32 requested, u16 cmd)
3728{
3729 struct common_audit_data ad;
3730 struct file_security_struct *fsec = selinux_file(file);
3731 struct inode *inode = file_inode(file);
3732 struct inode_security_struct *isec;
3733 struct lsm_ioctlop_audit ioctl;
3734 u32 ssid = cred_sid(cred);
3735 int rc;
3736 u8 driver = cmd >> 8;
3737 u8 xperm = cmd & 0xff;
3738
3739 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3740 ad.u.op = &ioctl;
3741 ad.u.op->cmd = cmd;
3742 ad.u.op->path = file->f_path;
3743
3744 if (ssid != fsec->sid) {
3745 rc = avc_has_perm(&selinux_state,
3746 ssid, fsec->sid,
3747 SECCLASS_FD,
3748 FD__USE,
3749 &ad);
3750 if (rc)
3751 goto out;
3752 }
3753
3754 if (unlikely(IS_PRIVATE(inode)))
3755 return 0;
3756
3757 isec = inode_security(inode);
3758 rc = avc_has_extended_perms(&selinux_state,
3759 ssid, isec->sid, isec->sclass,
3760 requested, driver, xperm, &ad);
3761out:
3762 return rc;
3763}
3764
3765static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3766 unsigned long arg)
3767{
3768 const struct cred *cred = current_cred();
3769 int error = 0;
3770
3771 switch (cmd) {
3772 case FIONREAD:
3773 case FIBMAP:
3774 case FIGETBSZ:
3775 case FS_IOC_GETFLAGS:
3776 case FS_IOC_GETVERSION:
3777 error = file_has_perm(cred, file, FILE__GETATTR);
3778 break;
3779
3780 case FS_IOC_SETFLAGS:
3781 case FS_IOC_SETVERSION:
3782 error = file_has_perm(cred, file, FILE__SETATTR);
3783 break;
3784
3785 /* sys_ioctl() checks */
3786 case FIONBIO:
3787 case FIOASYNC:
3788 error = file_has_perm(cred, file, 0);
3789 break;
3790
3791 case KDSKBENT:
3792 case KDSKBSENT:
3793 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3794 CAP_OPT_NONE, true);
3795 break;
3796
3797 /* default case assumes that the command will go
3798 * to the file's ioctl() function.
3799 */
3800 default:
3801 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3802 }
3803 return error;
3804}
3805
3806static int default_noexec __ro_after_init;
3807
3808static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3809{
3810 const struct cred *cred = current_cred();
3811 u32 sid = cred_sid(cred);
3812 int rc = 0;
3813
3814 if (default_noexec &&
3815 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3816 (!shared && (prot & PROT_WRITE)))) {
3817 /*
3818 * We are making executable an anonymous mapping or a
3819 * private file mapping that will also be writable.
3820 * This has an additional check.
3821 */
3822 rc = avc_has_perm(&selinux_state,
3823 sid, sid, SECCLASS_PROCESS,
3824 PROCESS__EXECMEM, NULL);
3825 if (rc)
3826 goto error;
3827 }
3828
3829 if (file) {
3830 /* read access is always possible with a mapping */
3831 u32 av = FILE__READ;
3832
3833 /* write access only matters if the mapping is shared */
3834 if (shared && (prot & PROT_WRITE))
3835 av |= FILE__WRITE;
3836
3837 if (prot & PROT_EXEC)
3838 av |= FILE__EXECUTE;
3839
3840 return file_has_perm(cred, file, av);
3841 }
3842
3843error:
3844 return rc;
3845}
3846
3847static int selinux_mmap_addr(unsigned long addr)
3848{
3849 int rc = 0;
3850
3851 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3852 u32 sid = current_sid();
3853 rc = avc_has_perm(&selinux_state,
3854 sid, sid, SECCLASS_MEMPROTECT,
3855 MEMPROTECT__MMAP_ZERO, NULL);
3856 }
3857
3858 return rc;
3859}
3860
3861static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3862 unsigned long prot, unsigned long flags)
3863{
3864 struct common_audit_data ad;
3865 int rc;
3866
3867 if (file) {
3868 ad.type = LSM_AUDIT_DATA_FILE;
3869 ad.u.file = file;
3870 rc = inode_has_perm(current_cred(), file_inode(file),
3871 FILE__MAP, &ad);
3872 if (rc)
3873 return rc;
3874 }
3875
3876 if (checkreqprot_get(&selinux_state))
3877 prot = reqprot;
3878
3879 return file_map_prot_check(file, prot,
3880 (flags & MAP_TYPE) == MAP_SHARED);
3881}
3882
3883static int selinux_file_mprotect(struct vm_area_struct *vma,
3884 unsigned long reqprot,
3885 unsigned long prot)
3886{
3887 const struct cred *cred = current_cred();
3888 u32 sid = cred_sid(cred);
3889
3890 if (checkreqprot_get(&selinux_state))
3891 prot = reqprot;
3892
3893 if (default_noexec &&
3894 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3895 int rc = 0;
3896 if (vma->vm_start >= vma->vm_mm->start_brk &&
3897 vma->vm_end <= vma->vm_mm->brk) {
3898 rc = avc_has_perm(&selinux_state,
3899 sid, sid, SECCLASS_PROCESS,
3900 PROCESS__EXECHEAP, NULL);
3901 } else if (!vma->vm_file &&
3902 ((vma->vm_start <= vma->vm_mm->start_stack &&
3903 vma->vm_end >= vma->vm_mm->start_stack) ||
3904 vma_is_stack_for_current(vma))) {
3905 rc = avc_has_perm(&selinux_state,
3906 sid, sid, SECCLASS_PROCESS,
3907 PROCESS__EXECSTACK, NULL);
3908 } else if (vma->vm_file && vma->anon_vma) {
3909 /*
3910 * We are making executable a file mapping that has
3911 * had some COW done. Since pages might have been
3912 * written, check ability to execute the possibly
3913 * modified content. This typically should only
3914 * occur for text relocations.
3915 */
3916 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3917 }
3918 if (rc)
3919 return rc;
3920 }
3921
3922 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3923}
3924
3925static int selinux_file_lock(struct file *file, unsigned int cmd)
3926{
3927 const struct cred *cred = current_cred();
3928
3929 return file_has_perm(cred, file, FILE__LOCK);
3930}
3931
3932static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3933 unsigned long arg)
3934{
3935 const struct cred *cred = current_cred();
3936 int err = 0;
3937
3938 switch (cmd) {
3939 case F_SETFL:
3940 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3941 err = file_has_perm(cred, file, FILE__WRITE);
3942 break;
3943 }
3944 fallthrough;
3945 case F_SETOWN:
3946 case F_SETSIG:
3947 case F_GETFL:
3948 case F_GETOWN:
3949 case F_GETSIG:
3950 case F_GETOWNER_UIDS:
3951 /* Just check FD__USE permission */
3952 err = file_has_perm(cred, file, 0);
3953 break;
3954 case F_GETLK:
3955 case F_SETLK:
3956 case F_SETLKW:
3957 case F_OFD_GETLK:
3958 case F_OFD_SETLK:
3959 case F_OFD_SETLKW:
3960#if BITS_PER_LONG == 32
3961 case F_GETLK64:
3962 case F_SETLK64:
3963 case F_SETLKW64:
3964#endif
3965 err = file_has_perm(cred, file, FILE__LOCK);
3966 break;
3967 }
3968
3969 return err;
3970}
3971
3972static void selinux_file_set_fowner(struct file *file)
3973{
3974 struct file_security_struct *fsec;
3975
3976 fsec = selinux_file(file);
3977 fsec->fown_sid = current_sid();
3978}
3979
3980static int selinux_file_send_sigiotask(struct task_struct *tsk,
3981 struct fown_struct *fown, int signum)
3982{
3983 struct file *file;
3984 u32 sid = task_sid_obj(tsk);
3985 u32 perm;
3986 struct file_security_struct *fsec;
3987
3988 /* struct fown_struct is never outside the context of a struct file */
3989 file = container_of(fown, struct file, f_owner);
3990
3991 fsec = selinux_file(file);
3992
3993 if (!signum)
3994 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3995 else
3996 perm = signal_to_av(signum);
3997
3998 return avc_has_perm(&selinux_state,
3999 fsec->fown_sid, sid,
4000 SECCLASS_PROCESS, perm, NULL);
4001}
4002
4003static int selinux_file_receive(struct file *file)
4004{
4005 const struct cred *cred = current_cred();
4006
4007 return file_has_perm(cred, file, file_to_av(file));
4008}
4009
4010static int selinux_file_open(struct file *file)
4011{
4012 struct file_security_struct *fsec;
4013 struct inode_security_struct *isec;
4014
4015 fsec = selinux_file(file);
4016 isec = inode_security(file_inode(file));
4017 /*
4018 * Save inode label and policy sequence number
4019 * at open-time so that selinux_file_permission
4020 * can determine whether revalidation is necessary.
4021 * Task label is already saved in the file security
4022 * struct as its SID.
4023 */
4024 fsec->isid = isec->sid;
4025 fsec->pseqno = avc_policy_seqno(&selinux_state);
4026 /*
4027 * Since the inode label or policy seqno may have changed
4028 * between the selinux_inode_permission check and the saving
4029 * of state above, recheck that access is still permitted.
4030 * Otherwise, access might never be revalidated against the
4031 * new inode label or new policy.
4032 * This check is not redundant - do not remove.
4033 */
4034 return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
4035}
4036
4037/* task security operations */
4038
4039static int selinux_task_alloc(struct task_struct *task,
4040 unsigned long clone_flags)
4041{
4042 u32 sid = current_sid();
4043
4044 return avc_has_perm(&selinux_state,
4045 sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
4046}
4047
4048/*
4049 * prepare a new set of credentials for modification
4050 */
4051static int selinux_cred_prepare(struct cred *new, const struct cred *old,
4052 gfp_t gfp)
4053{
4054 const struct task_security_struct *old_tsec = selinux_cred(old);
4055 struct task_security_struct *tsec = selinux_cred(new);
4056
4057 *tsec = *old_tsec;
4058 return 0;
4059}
4060
4061/*
4062 * transfer the SELinux data to a blank set of creds
4063 */
4064static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4065{
4066 const struct task_security_struct *old_tsec = selinux_cred(old);
4067 struct task_security_struct *tsec = selinux_cred(new);
4068
4069 *tsec = *old_tsec;
4070}
4071
4072static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4073{
4074 *secid = cred_sid(c);
4075}
4076
4077/*
4078 * set the security data for a kernel service
4079 * - all the creation contexts are set to unlabelled
4080 */
4081static int selinux_kernel_act_as(struct cred *new, u32 secid)
4082{
4083 struct task_security_struct *tsec = selinux_cred(new);
4084 u32 sid = current_sid();
4085 int ret;
4086
4087 ret = avc_has_perm(&selinux_state,
4088 sid, secid,
4089 SECCLASS_KERNEL_SERVICE,
4090 KERNEL_SERVICE__USE_AS_OVERRIDE,
4091 NULL);
4092 if (ret == 0) {
4093 tsec->sid = secid;
4094 tsec->create_sid = 0;
4095 tsec->keycreate_sid = 0;
4096 tsec->sockcreate_sid = 0;
4097 }
4098 return ret;
4099}
4100
4101/*
4102 * set the file creation context in a security record to the same as the
4103 * objective context of the specified inode
4104 */
4105static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4106{
4107 struct inode_security_struct *isec = inode_security(inode);
4108 struct task_security_struct *tsec = selinux_cred(new);
4109 u32 sid = current_sid();
4110 int ret;
4111
4112 ret = avc_has_perm(&selinux_state,
4113 sid, isec->sid,
4114 SECCLASS_KERNEL_SERVICE,
4115 KERNEL_SERVICE__CREATE_FILES_AS,
4116 NULL);
4117
4118 if (ret == 0)
4119 tsec->create_sid = isec->sid;
4120 return ret;
4121}
4122
4123static int selinux_kernel_module_request(char *kmod_name)
4124{
4125 struct common_audit_data ad;
4126
4127 ad.type = LSM_AUDIT_DATA_KMOD;
4128 ad.u.kmod_name = kmod_name;
4129
4130 return avc_has_perm(&selinux_state,
4131 current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4132 SYSTEM__MODULE_REQUEST, &ad);
4133}
4134
4135static int selinux_kernel_module_from_file(struct file *file)
4136{
4137 struct common_audit_data ad;
4138 struct inode_security_struct *isec;
4139 struct file_security_struct *fsec;
4140 u32 sid = current_sid();
4141 int rc;
4142
4143 /* init_module */
4144 if (file == NULL)
4145 return avc_has_perm(&selinux_state,
4146 sid, sid, SECCLASS_SYSTEM,
4147 SYSTEM__MODULE_LOAD, NULL);
4148
4149 /* finit_module */
4150
4151 ad.type = LSM_AUDIT_DATA_FILE;
4152 ad.u.file = file;
4153
4154 fsec = selinux_file(file);
4155 if (sid != fsec->sid) {
4156 rc = avc_has_perm(&selinux_state,
4157 sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4158 if (rc)
4159 return rc;
4160 }
4161
4162 isec = inode_security(file_inode(file));
4163 return avc_has_perm(&selinux_state,
4164 sid, isec->sid, SECCLASS_SYSTEM,
4165 SYSTEM__MODULE_LOAD, &ad);
4166}
4167
4168static int selinux_kernel_read_file(struct file *file,
4169 enum kernel_read_file_id id,
4170 bool contents)
4171{
4172 int rc = 0;
4173
4174 switch (id) {
4175 case READING_MODULE:
4176 rc = selinux_kernel_module_from_file(contents ? file : NULL);
4177 break;
4178 default:
4179 break;
4180 }
4181
4182 return rc;
4183}
4184
4185static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4186{
4187 int rc = 0;
4188
4189 switch (id) {
4190 case LOADING_MODULE:
4191 rc = selinux_kernel_module_from_file(NULL);
4192 break;
4193 default:
4194 break;
4195 }
4196
4197 return rc;
4198}
4199
4200static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4201{
4202 return avc_has_perm(&selinux_state,
4203 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4204 PROCESS__SETPGID, NULL);
4205}
4206
4207static int selinux_task_getpgid(struct task_struct *p)
4208{
4209 return avc_has_perm(&selinux_state,
4210 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4211 PROCESS__GETPGID, NULL);
4212}
4213
4214static int selinux_task_getsid(struct task_struct *p)
4215{
4216 return avc_has_perm(&selinux_state,
4217 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4218 PROCESS__GETSESSION, NULL);
4219}
4220
4221static void selinux_task_getsecid_subj(struct task_struct *p, u32 *secid)
4222{
4223 *secid = task_sid_subj(p);
4224}
4225
4226static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid)
4227{
4228 *secid = task_sid_obj(p);
4229}
4230
4231static int selinux_task_setnice(struct task_struct *p, int nice)
4232{
4233 return avc_has_perm(&selinux_state,
4234 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4235 PROCESS__SETSCHED, NULL);
4236}
4237
4238static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4239{
4240 return avc_has_perm(&selinux_state,
4241 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4242 PROCESS__SETSCHED, NULL);
4243}
4244
4245static int selinux_task_getioprio(struct task_struct *p)
4246{
4247 return avc_has_perm(&selinux_state,
4248 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4249 PROCESS__GETSCHED, NULL);
4250}
4251
4252static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4253 unsigned int flags)
4254{
4255 u32 av = 0;
4256
4257 if (!flags)
4258 return 0;
4259 if (flags & LSM_PRLIMIT_WRITE)
4260 av |= PROCESS__SETRLIMIT;
4261 if (flags & LSM_PRLIMIT_READ)
4262 av |= PROCESS__GETRLIMIT;
4263 return avc_has_perm(&selinux_state,
4264 cred_sid(cred), cred_sid(tcred),
4265 SECCLASS_PROCESS, av, NULL);
4266}
4267
4268static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4269 struct rlimit *new_rlim)
4270{
4271 struct rlimit *old_rlim = p->signal->rlim + resource;
4272
4273 /* Control the ability to change the hard limit (whether
4274 lowering or raising it), so that the hard limit can
4275 later be used as a safe reset point for the soft limit
4276 upon context transitions. See selinux_bprm_committing_creds. */
4277 if (old_rlim->rlim_max != new_rlim->rlim_max)
4278 return avc_has_perm(&selinux_state,
4279 current_sid(), task_sid_obj(p),
4280 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4281
4282 return 0;
4283}
4284
4285static int selinux_task_setscheduler(struct task_struct *p)
4286{
4287 return avc_has_perm(&selinux_state,
4288 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4289 PROCESS__SETSCHED, NULL);
4290}
4291
4292static int selinux_task_getscheduler(struct task_struct *p)
4293{
4294 return avc_has_perm(&selinux_state,
4295 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4296 PROCESS__GETSCHED, NULL);
4297}
4298
4299static int selinux_task_movememory(struct task_struct *p)
4300{
4301 return avc_has_perm(&selinux_state,
4302 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4303 PROCESS__SETSCHED, NULL);
4304}
4305
4306static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4307 int sig, const struct cred *cred)
4308{
4309 u32 secid;
4310 u32 perm;
4311
4312 if (!sig)
4313 perm = PROCESS__SIGNULL; /* null signal; existence test */
4314 else
4315 perm = signal_to_av(sig);
4316 if (!cred)
4317 secid = current_sid();
4318 else
4319 secid = cred_sid(cred);
4320 return avc_has_perm(&selinux_state,
4321 secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4322}
4323
4324static void selinux_task_to_inode(struct task_struct *p,
4325 struct inode *inode)
4326{
4327 struct inode_security_struct *isec = selinux_inode(inode);
4328 u32 sid = task_sid_obj(p);
4329
4330 spin_lock(&isec->lock);
4331 isec->sclass = inode_mode_to_security_class(inode->i_mode);
4332 isec->sid = sid;
4333 isec->initialized = LABEL_INITIALIZED;
4334 spin_unlock(&isec->lock);
4335}
4336
4337/* Returns error only if unable to parse addresses */
4338static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4339 struct common_audit_data *ad, u8 *proto)
4340{
4341 int offset, ihlen, ret = -EINVAL;
4342 struct iphdr _iph, *ih;
4343
4344 offset = skb_network_offset(skb);
4345 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4346 if (ih == NULL)
4347 goto out;
4348
4349 ihlen = ih->ihl * 4;
4350 if (ihlen < sizeof(_iph))
4351 goto out;
4352
4353 ad->u.net->v4info.saddr = ih->saddr;
4354 ad->u.net->v4info.daddr = ih->daddr;
4355 ret = 0;
4356
4357 if (proto)
4358 *proto = ih->protocol;
4359
4360 switch (ih->protocol) {
4361 case IPPROTO_TCP: {
4362 struct tcphdr _tcph, *th;
4363
4364 if (ntohs(ih->frag_off) & IP_OFFSET)
4365 break;
4366
4367 offset += ihlen;
4368 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4369 if (th == NULL)
4370 break;
4371
4372 ad->u.net->sport = th->source;
4373 ad->u.net->dport = th->dest;
4374 break;
4375 }
4376
4377 case IPPROTO_UDP: {
4378 struct udphdr _udph, *uh;
4379
4380 if (ntohs(ih->frag_off) & IP_OFFSET)
4381 break;
4382
4383 offset += ihlen;
4384 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4385 if (uh == NULL)
4386 break;
4387
4388 ad->u.net->sport = uh->source;
4389 ad->u.net->dport = uh->dest;
4390 break;
4391 }
4392
4393 case IPPROTO_DCCP: {
4394 struct dccp_hdr _dccph, *dh;
4395
4396 if (ntohs(ih->frag_off) & IP_OFFSET)
4397 break;
4398
4399 offset += ihlen;
4400 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4401 if (dh == NULL)
4402 break;
4403
4404 ad->u.net->sport = dh->dccph_sport;
4405 ad->u.net->dport = dh->dccph_dport;
4406 break;
4407 }
4408
4409#if IS_ENABLED(CONFIG_IP_SCTP)
4410 case IPPROTO_SCTP: {
4411 struct sctphdr _sctph, *sh;
4412
4413 if (ntohs(ih->frag_off) & IP_OFFSET)
4414 break;
4415
4416 offset += ihlen;
4417 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4418 if (sh == NULL)
4419 break;
4420
4421 ad->u.net->sport = sh->source;
4422 ad->u.net->dport = sh->dest;
4423 break;
4424 }
4425#endif
4426 default:
4427 break;
4428 }
4429out:
4430 return ret;
4431}
4432
4433#if IS_ENABLED(CONFIG_IPV6)
4434
4435/* Returns error only if unable to parse addresses */
4436static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4437 struct common_audit_data *ad, u8 *proto)
4438{
4439 u8 nexthdr;
4440 int ret = -EINVAL, offset;
4441 struct ipv6hdr _ipv6h, *ip6;
4442 __be16 frag_off;
4443
4444 offset = skb_network_offset(skb);
4445 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4446 if (ip6 == NULL)
4447 goto out;
4448
4449 ad->u.net->v6info.saddr = ip6->saddr;
4450 ad->u.net->v6info.daddr = ip6->daddr;
4451 ret = 0;
4452
4453 nexthdr = ip6->nexthdr;
4454 offset += sizeof(_ipv6h);
4455 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4456 if (offset < 0)
4457 goto out;
4458
4459 if (proto)
4460 *proto = nexthdr;
4461
4462 switch (nexthdr) {
4463 case IPPROTO_TCP: {
4464 struct tcphdr _tcph, *th;
4465
4466 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4467 if (th == NULL)
4468 break;
4469
4470 ad->u.net->sport = th->source;
4471 ad->u.net->dport = th->dest;
4472 break;
4473 }
4474
4475 case IPPROTO_UDP: {
4476 struct udphdr _udph, *uh;
4477
4478 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4479 if (uh == NULL)
4480 break;
4481
4482 ad->u.net->sport = uh->source;
4483 ad->u.net->dport = uh->dest;
4484 break;
4485 }
4486
4487 case IPPROTO_DCCP: {
4488 struct dccp_hdr _dccph, *dh;
4489
4490 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4491 if (dh == NULL)
4492 break;
4493
4494 ad->u.net->sport = dh->dccph_sport;
4495 ad->u.net->dport = dh->dccph_dport;
4496 break;
4497 }
4498
4499#if IS_ENABLED(CONFIG_IP_SCTP)
4500 case IPPROTO_SCTP: {
4501 struct sctphdr _sctph, *sh;
4502
4503 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4504 if (sh == NULL)
4505 break;
4506
4507 ad->u.net->sport = sh->source;
4508 ad->u.net->dport = sh->dest;
4509 break;
4510 }
4511#endif
4512 /* includes fragments */
4513 default:
4514 break;
4515 }
4516out:
4517 return ret;
4518}
4519
4520#endif /* IPV6 */
4521
4522static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4523 char **_addrp, int src, u8 *proto)
4524{
4525 char *addrp;
4526 int ret;
4527
4528 switch (ad->u.net->family) {
4529 case PF_INET:
4530 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4531 if (ret)
4532 goto parse_error;
4533 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4534 &ad->u.net->v4info.daddr);
4535 goto okay;
4536
4537#if IS_ENABLED(CONFIG_IPV6)
4538 case PF_INET6:
4539 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4540 if (ret)
4541 goto parse_error;
4542 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4543 &ad->u.net->v6info.daddr);
4544 goto okay;
4545#endif /* IPV6 */
4546 default:
4547 addrp = NULL;
4548 goto okay;
4549 }
4550
4551parse_error:
4552 pr_warn(
4553 "SELinux: failure in selinux_parse_skb(),"
4554 " unable to parse packet\n");
4555 return ret;
4556
4557okay:
4558 if (_addrp)
4559 *_addrp = addrp;
4560 return 0;
4561}
4562
4563/**
4564 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4565 * @skb: the packet
4566 * @family: protocol family
4567 * @sid: the packet's peer label SID
4568 *
4569 * Description:
4570 * Check the various different forms of network peer labeling and determine
4571 * the peer label/SID for the packet; most of the magic actually occurs in
4572 * the security server function security_net_peersid_cmp(). The function
4573 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4574 * or -EACCES if @sid is invalid due to inconsistencies with the different
4575 * peer labels.
4576 *
4577 */
4578static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4579{
4580 int err;
4581 u32 xfrm_sid;
4582 u32 nlbl_sid;
4583 u32 nlbl_type;
4584
4585 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4586 if (unlikely(err))
4587 return -EACCES;
4588 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4589 if (unlikely(err))
4590 return -EACCES;
4591
4592 err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4593 nlbl_type, xfrm_sid, sid);
4594 if (unlikely(err)) {
4595 pr_warn(
4596 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4597 " unable to determine packet's peer label\n");
4598 return -EACCES;
4599 }
4600
4601 return 0;
4602}
4603
4604/**
4605 * selinux_conn_sid - Determine the child socket label for a connection
4606 * @sk_sid: the parent socket's SID
4607 * @skb_sid: the packet's SID
4608 * @conn_sid: the resulting connection SID
4609 *
4610 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4611 * combined with the MLS information from @skb_sid in order to create
4612 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy
4613 * of @sk_sid. Returns zero on success, negative values on failure.
4614 *
4615 */
4616static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4617{
4618 int err = 0;
4619
4620 if (skb_sid != SECSID_NULL)
4621 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4622 conn_sid);
4623 else
4624 *conn_sid = sk_sid;
4625
4626 return err;
4627}
4628
4629/* socket security operations */
4630
4631static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4632 u16 secclass, u32 *socksid)
4633{
4634 if (tsec->sockcreate_sid > SECSID_NULL) {
4635 *socksid = tsec->sockcreate_sid;
4636 return 0;
4637 }
4638
4639 return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4640 secclass, NULL, socksid);
4641}
4642
4643static int sock_has_perm(struct sock *sk, u32 perms)
4644{
4645 struct sk_security_struct *sksec = sk->sk_security;
4646 struct common_audit_data ad;
4647 struct lsm_network_audit net = {0,};
4648
4649 if (sksec->sid == SECINITSID_KERNEL)
4650 return 0;
4651
4652 ad.type = LSM_AUDIT_DATA_NET;
4653 ad.u.net = &net;
4654 ad.u.net->sk = sk;
4655
4656 return avc_has_perm(&selinux_state,
4657 current_sid(), sksec->sid, sksec->sclass, perms,
4658 &ad);
4659}
4660
4661static int selinux_socket_create(int family, int type,
4662 int protocol, int kern)
4663{
4664 const struct task_security_struct *tsec = selinux_cred(current_cred());
4665 u32 newsid;
4666 u16 secclass;
4667 int rc;
4668
4669 if (kern)
4670 return 0;
4671
4672 secclass = socket_type_to_security_class(family, type, protocol);
4673 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4674 if (rc)
4675 return rc;
4676
4677 return avc_has_perm(&selinux_state,
4678 tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4679}
4680
4681static int selinux_socket_post_create(struct socket *sock, int family,
4682 int type, int protocol, int kern)
4683{
4684 const struct task_security_struct *tsec = selinux_cred(current_cred());
4685 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4686 struct sk_security_struct *sksec;
4687 u16 sclass = socket_type_to_security_class(family, type, protocol);
4688 u32 sid = SECINITSID_KERNEL;
4689 int err = 0;
4690
4691 if (!kern) {
4692 err = socket_sockcreate_sid(tsec, sclass, &sid);
4693 if (err)
4694 return err;
4695 }
4696
4697 isec->sclass = sclass;
4698 isec->sid = sid;
4699 isec->initialized = LABEL_INITIALIZED;
4700
4701 if (sock->sk) {
4702 sksec = sock->sk->sk_security;
4703 sksec->sclass = sclass;
4704 sksec->sid = sid;
4705 /* Allows detection of the first association on this socket */
4706 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4707 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4708
4709 err = selinux_netlbl_socket_post_create(sock->sk, family);
4710 }
4711
4712 return err;
4713}
4714
4715static int selinux_socket_socketpair(struct socket *socka,
4716 struct socket *sockb)
4717{
4718 struct sk_security_struct *sksec_a = socka->sk->sk_security;
4719 struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4720
4721 sksec_a->peer_sid = sksec_b->sid;
4722 sksec_b->peer_sid = sksec_a->sid;
4723
4724 return 0;
4725}
4726
4727/* Range of port numbers used to automatically bind.
4728 Need to determine whether we should perform a name_bind
4729 permission check between the socket and the port number. */
4730
4731static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4732{
4733 struct sock *sk = sock->sk;
4734 struct sk_security_struct *sksec = sk->sk_security;
4735 u16 family;
4736 int err;
4737
4738 err = sock_has_perm(sk, SOCKET__BIND);
4739 if (err)
4740 goto out;
4741
4742 /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4743 family = sk->sk_family;
4744 if (family == PF_INET || family == PF_INET6) {
4745 char *addrp;
4746 struct common_audit_data ad;
4747 struct lsm_network_audit net = {0,};
4748 struct sockaddr_in *addr4 = NULL;
4749 struct sockaddr_in6 *addr6 = NULL;
4750 u16 family_sa;
4751 unsigned short snum;
4752 u32 sid, node_perm;
4753
4754 /*
4755 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4756 * that validates multiple binding addresses. Because of this
4757 * need to check address->sa_family as it is possible to have
4758 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4759 */
4760 if (addrlen < offsetofend(struct sockaddr, sa_family))
4761 return -EINVAL;
4762 family_sa = address->sa_family;
4763 switch (family_sa) {
4764 case AF_UNSPEC:
4765 case AF_INET:
4766 if (addrlen < sizeof(struct sockaddr_in))
4767 return -EINVAL;
4768 addr4 = (struct sockaddr_in *)address;
4769 if (family_sa == AF_UNSPEC) {
4770 /* see __inet_bind(), we only want to allow
4771 * AF_UNSPEC if the address is INADDR_ANY
4772 */
4773 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4774 goto err_af;
4775 family_sa = AF_INET;
4776 }
4777 snum = ntohs(addr4->sin_port);
4778 addrp = (char *)&addr4->sin_addr.s_addr;
4779 break;
4780 case AF_INET6:
4781 if (addrlen < SIN6_LEN_RFC2133)
4782 return -EINVAL;
4783 addr6 = (struct sockaddr_in6 *)address;
4784 snum = ntohs(addr6->sin6_port);
4785 addrp = (char *)&addr6->sin6_addr.s6_addr;
4786 break;
4787 default:
4788 goto err_af;
4789 }
4790
4791 ad.type = LSM_AUDIT_DATA_NET;
4792 ad.u.net = &net;
4793 ad.u.net->sport = htons(snum);
4794 ad.u.net->family = family_sa;
4795
4796 if (snum) {
4797 int low, high;
4798
4799 inet_get_local_port_range(sock_net(sk), &low, &high);
4800
4801 if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4802 snum < low || snum > high) {
4803 err = sel_netport_sid(sk->sk_protocol,
4804 snum, &sid);
4805 if (err)
4806 goto out;
4807 err = avc_has_perm(&selinux_state,
4808 sksec->sid, sid,
4809 sksec->sclass,
4810 SOCKET__NAME_BIND, &ad);
4811 if (err)
4812 goto out;
4813 }
4814 }
4815
4816 switch (sksec->sclass) {
4817 case SECCLASS_TCP_SOCKET:
4818 node_perm = TCP_SOCKET__NODE_BIND;
4819 break;
4820
4821 case SECCLASS_UDP_SOCKET:
4822 node_perm = UDP_SOCKET__NODE_BIND;
4823 break;
4824
4825 case SECCLASS_DCCP_SOCKET:
4826 node_perm = DCCP_SOCKET__NODE_BIND;
4827 break;
4828
4829 case SECCLASS_SCTP_SOCKET:
4830 node_perm = SCTP_SOCKET__NODE_BIND;
4831 break;
4832
4833 default:
4834 node_perm = RAWIP_SOCKET__NODE_BIND;
4835 break;
4836 }
4837
4838 err = sel_netnode_sid(addrp, family_sa, &sid);
4839 if (err)
4840 goto out;
4841
4842 if (family_sa == AF_INET)
4843 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4844 else
4845 ad.u.net->v6info.saddr = addr6->sin6_addr;
4846
4847 err = avc_has_perm(&selinux_state,
4848 sksec->sid, sid,
4849 sksec->sclass, node_perm, &ad);
4850 if (err)
4851 goto out;
4852 }
4853out:
4854 return err;
4855err_af:
4856 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4857 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4858 return -EINVAL;
4859 return -EAFNOSUPPORT;
4860}
4861
4862/* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4863 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4864 */
4865static int selinux_socket_connect_helper(struct socket *sock,
4866 struct sockaddr *address, int addrlen)
4867{
4868 struct sock *sk = sock->sk;
4869 struct sk_security_struct *sksec = sk->sk_security;
4870 int err;
4871
4872 err = sock_has_perm(sk, SOCKET__CONNECT);
4873 if (err)
4874 return err;
4875 if (addrlen < offsetofend(struct sockaddr, sa_family))
4876 return -EINVAL;
4877
4878 /* connect(AF_UNSPEC) has special handling, as it is a documented
4879 * way to disconnect the socket
4880 */
4881 if (address->sa_family == AF_UNSPEC)
4882 return 0;
4883
4884 /*
4885 * If a TCP, DCCP or SCTP socket, check name_connect permission
4886 * for the port.
4887 */
4888 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4889 sksec->sclass == SECCLASS_DCCP_SOCKET ||
4890 sksec->sclass == SECCLASS_SCTP_SOCKET) {
4891 struct common_audit_data ad;
4892 struct lsm_network_audit net = {0,};
4893 struct sockaddr_in *addr4 = NULL;
4894 struct sockaddr_in6 *addr6 = NULL;
4895 unsigned short snum;
4896 u32 sid, perm;
4897
4898 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4899 * that validates multiple connect addresses. Because of this
4900 * need to check address->sa_family as it is possible to have
4901 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4902 */
4903 switch (address->sa_family) {
4904 case AF_INET:
4905 addr4 = (struct sockaddr_in *)address;
4906 if (addrlen < sizeof(struct sockaddr_in))
4907 return -EINVAL;
4908 snum = ntohs(addr4->sin_port);
4909 break;
4910 case AF_INET6:
4911 addr6 = (struct sockaddr_in6 *)address;
4912 if (addrlen < SIN6_LEN_RFC2133)
4913 return -EINVAL;
4914 snum = ntohs(addr6->sin6_port);
4915 break;
4916 default:
4917 /* Note that SCTP services expect -EINVAL, whereas
4918 * others expect -EAFNOSUPPORT.
4919 */
4920 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4921 return -EINVAL;
4922 else
4923 return -EAFNOSUPPORT;
4924 }
4925
4926 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4927 if (err)
4928 return err;
4929
4930 switch (sksec->sclass) {
4931 case SECCLASS_TCP_SOCKET:
4932 perm = TCP_SOCKET__NAME_CONNECT;
4933 break;
4934 case SECCLASS_DCCP_SOCKET:
4935 perm = DCCP_SOCKET__NAME_CONNECT;
4936 break;
4937 case SECCLASS_SCTP_SOCKET:
4938 perm = SCTP_SOCKET__NAME_CONNECT;
4939 break;
4940 }
4941
4942 ad.type = LSM_AUDIT_DATA_NET;
4943 ad.u.net = &net;
4944 ad.u.net->dport = htons(snum);
4945 ad.u.net->family = address->sa_family;
4946 err = avc_has_perm(&selinux_state,
4947 sksec->sid, sid, sksec->sclass, perm, &ad);
4948 if (err)
4949 return err;
4950 }
4951
4952 return 0;
4953}
4954
4955/* Supports connect(2), see comments in selinux_socket_connect_helper() */
4956static int selinux_socket_connect(struct socket *sock,
4957 struct sockaddr *address, int addrlen)
4958{
4959 int err;
4960 struct sock *sk = sock->sk;
4961
4962 err = selinux_socket_connect_helper(sock, address, addrlen);
4963 if (err)
4964 return err;
4965
4966 return selinux_netlbl_socket_connect(sk, address);
4967}
4968
4969static int selinux_socket_listen(struct socket *sock, int backlog)
4970{
4971 return sock_has_perm(sock->sk, SOCKET__LISTEN);
4972}
4973
4974static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4975{
4976 int err;
4977 struct inode_security_struct *isec;
4978 struct inode_security_struct *newisec;
4979 u16 sclass;
4980 u32 sid;
4981
4982 err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4983 if (err)
4984 return err;
4985
4986 isec = inode_security_novalidate(SOCK_INODE(sock));
4987 spin_lock(&isec->lock);
4988 sclass = isec->sclass;
4989 sid = isec->sid;
4990 spin_unlock(&isec->lock);
4991
4992 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4993 newisec->sclass = sclass;
4994 newisec->sid = sid;
4995 newisec->initialized = LABEL_INITIALIZED;
4996
4997 return 0;
4998}
4999
5000static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
5001 int size)
5002{
5003 return sock_has_perm(sock->sk, SOCKET__WRITE);
5004}
5005
5006static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
5007 int size, int flags)
5008{
5009 return sock_has_perm(sock->sk, SOCKET__READ);
5010}
5011
5012static int selinux_socket_getsockname(struct socket *sock)
5013{
5014 return sock_has_perm(sock->sk, SOCKET__GETATTR);
5015}
5016
5017static int selinux_socket_getpeername(struct socket *sock)
5018{
5019 return sock_has_perm(sock->sk, SOCKET__GETATTR);
5020}
5021
5022static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
5023{
5024 int err;
5025
5026 err = sock_has_perm(sock->sk, SOCKET__SETOPT);
5027 if (err)
5028 return err;
5029
5030 return selinux_netlbl_socket_setsockopt(sock, level, optname);
5031}
5032
5033static int selinux_socket_getsockopt(struct socket *sock, int level,
5034 int optname)
5035{
5036 return sock_has_perm(sock->sk, SOCKET__GETOPT);
5037}
5038
5039static int selinux_socket_shutdown(struct socket *sock, int how)
5040{
5041 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
5042}
5043
5044static int selinux_socket_unix_stream_connect(struct sock *sock,
5045 struct sock *other,
5046 struct sock *newsk)
5047{
5048 struct sk_security_struct *sksec_sock = sock->sk_security;
5049 struct sk_security_struct *sksec_other = other->sk_security;
5050 struct sk_security_struct *sksec_new = newsk->sk_security;
5051 struct common_audit_data ad;
5052 struct lsm_network_audit net = {0,};
5053 int err;
5054
5055 ad.type = LSM_AUDIT_DATA_NET;
5056 ad.u.net = &net;
5057 ad.u.net->sk = other;
5058
5059 err = avc_has_perm(&selinux_state,
5060 sksec_sock->sid, sksec_other->sid,
5061 sksec_other->sclass,
5062 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5063 if (err)
5064 return err;
5065
5066 /* server child socket */
5067 sksec_new->peer_sid = sksec_sock->sid;
5068 err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
5069 sksec_sock->sid, &sksec_new->sid);
5070 if (err)
5071 return err;
5072
5073 /* connecting socket */
5074 sksec_sock->peer_sid = sksec_new->sid;
5075
5076 return 0;
5077}
5078
5079static int selinux_socket_unix_may_send(struct socket *sock,
5080 struct socket *other)
5081{
5082 struct sk_security_struct *ssec = sock->sk->sk_security;
5083 struct sk_security_struct *osec = other->sk->sk_security;
5084 struct common_audit_data ad;
5085 struct lsm_network_audit net = {0,};
5086
5087 ad.type = LSM_AUDIT_DATA_NET;
5088 ad.u.net = &net;
5089 ad.u.net->sk = other->sk;
5090
5091 return avc_has_perm(&selinux_state,
5092 ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5093 &ad);
5094}
5095
5096static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5097 char *addrp, u16 family, u32 peer_sid,
5098 struct common_audit_data *ad)
5099{
5100 int err;
5101 u32 if_sid;
5102 u32 node_sid;
5103
5104 err = sel_netif_sid(ns, ifindex, &if_sid);
5105 if (err)
5106 return err;
5107 err = avc_has_perm(&selinux_state,
5108 peer_sid, if_sid,
5109 SECCLASS_NETIF, NETIF__INGRESS, ad);
5110 if (err)
5111 return err;
5112
5113 err = sel_netnode_sid(addrp, family, &node_sid);
5114 if (err)
5115 return err;
5116 return avc_has_perm(&selinux_state,
5117 peer_sid, node_sid,
5118 SECCLASS_NODE, NODE__RECVFROM, ad);
5119}
5120
5121static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5122 u16 family)
5123{
5124 int err = 0;
5125 struct sk_security_struct *sksec = sk->sk_security;
5126 u32 sk_sid = sksec->sid;
5127 struct common_audit_data ad;
5128 struct lsm_network_audit net = {0,};
5129 char *addrp;
5130
5131 ad.type = LSM_AUDIT_DATA_NET;
5132 ad.u.net = &net;
5133 ad.u.net->netif = skb->skb_iif;
5134 ad.u.net->family = family;
5135 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5136 if (err)
5137 return err;
5138
5139 if (selinux_secmark_enabled()) {
5140 err = avc_has_perm(&selinux_state,
5141 sk_sid, skb->secmark, SECCLASS_PACKET,
5142 PACKET__RECV, &ad);
5143 if (err)
5144 return err;
5145 }
5146
5147 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5148 if (err)
5149 return err;
5150 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5151
5152 return err;
5153}
5154
5155static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5156{
5157 int err;
5158 struct sk_security_struct *sksec = sk->sk_security;
5159 u16 family = sk->sk_family;
5160 u32 sk_sid = sksec->sid;
5161 struct common_audit_data ad;
5162 struct lsm_network_audit net = {0,};
5163 char *addrp;
5164 u8 secmark_active;
5165 u8 peerlbl_active;
5166
5167 if (family != PF_INET && family != PF_INET6)
5168 return 0;
5169
5170 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5171 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5172 family = PF_INET;
5173
5174 /* If any sort of compatibility mode is enabled then handoff processing
5175 * to the selinux_sock_rcv_skb_compat() function to deal with the
5176 * special handling. We do this in an attempt to keep this function
5177 * as fast and as clean as possible. */
5178 if (!selinux_policycap_netpeer())
5179 return selinux_sock_rcv_skb_compat(sk, skb, family);
5180
5181 secmark_active = selinux_secmark_enabled();
5182 peerlbl_active = selinux_peerlbl_enabled();
5183 if (!secmark_active && !peerlbl_active)
5184 return 0;
5185
5186 ad.type = LSM_AUDIT_DATA_NET;
5187 ad.u.net = &net;
5188 ad.u.net->netif = skb->skb_iif;
5189 ad.u.net->family = family;
5190 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5191 if (err)
5192 return err;
5193
5194 if (peerlbl_active) {
5195 u32 peer_sid;
5196
5197 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5198 if (err)
5199 return err;
5200 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5201 addrp, family, peer_sid, &ad);
5202 if (err) {
5203 selinux_netlbl_err(skb, family, err, 0);
5204 return err;
5205 }
5206 err = avc_has_perm(&selinux_state,
5207 sk_sid, peer_sid, SECCLASS_PEER,
5208 PEER__RECV, &ad);
5209 if (err) {
5210 selinux_netlbl_err(skb, family, err, 0);
5211 return err;
5212 }
5213 }
5214
5215 if (secmark_active) {
5216 err = avc_has_perm(&selinux_state,
5217 sk_sid, skb->secmark, SECCLASS_PACKET,
5218 PACKET__RECV, &ad);
5219 if (err)
5220 return err;
5221 }
5222
5223 return err;
5224}
5225
5226static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
5227 int __user *optlen, unsigned len)
5228{
5229 int err = 0;
5230 char *scontext;
5231 u32 scontext_len;
5232 struct sk_security_struct *sksec = sock->sk->sk_security;
5233 u32 peer_sid = SECSID_NULL;
5234
5235 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5236 sksec->sclass == SECCLASS_TCP_SOCKET ||
5237 sksec->sclass == SECCLASS_SCTP_SOCKET)
5238 peer_sid = sksec->peer_sid;
5239 if (peer_sid == SECSID_NULL)
5240 return -ENOPROTOOPT;
5241
5242 err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5243 &scontext_len);
5244 if (err)
5245 return err;
5246
5247 if (scontext_len > len) {
5248 err = -ERANGE;
5249 goto out_len;
5250 }
5251
5252 if (copy_to_user(optval, scontext, scontext_len))
5253 err = -EFAULT;
5254
5255out_len:
5256 if (put_user(scontext_len, optlen))
5257 err = -EFAULT;
5258 kfree(scontext);
5259 return err;
5260}
5261
5262static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5263{
5264 u32 peer_secid = SECSID_NULL;
5265 u16 family;
5266 struct inode_security_struct *isec;
5267
5268 if (skb && skb->protocol == htons(ETH_P_IP))
5269 family = PF_INET;
5270 else if (skb && skb->protocol == htons(ETH_P_IPV6))
5271 family = PF_INET6;
5272 else if (sock)
5273 family = sock->sk->sk_family;
5274 else
5275 goto out;
5276
5277 if (sock && family == PF_UNIX) {
5278 isec = inode_security_novalidate(SOCK_INODE(sock));
5279 peer_secid = isec->sid;
5280 } else if (skb)
5281 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5282
5283out:
5284 *secid = peer_secid;
5285 if (peer_secid == SECSID_NULL)
5286 return -EINVAL;
5287 return 0;
5288}
5289
5290static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5291{
5292 struct sk_security_struct *sksec;
5293
5294 sksec = kzalloc(sizeof(*sksec), priority);
5295 if (!sksec)
5296 return -ENOMEM;
5297
5298 sksec->peer_sid = SECINITSID_UNLABELED;
5299 sksec->sid = SECINITSID_UNLABELED;
5300 sksec->sclass = SECCLASS_SOCKET;
5301 selinux_netlbl_sk_security_reset(sksec);
5302 sk->sk_security = sksec;
5303
5304 return 0;
5305}
5306
5307static void selinux_sk_free_security(struct sock *sk)
5308{
5309 struct sk_security_struct *sksec = sk->sk_security;
5310
5311 sk->sk_security = NULL;
5312 selinux_netlbl_sk_security_free(sksec);
5313 kfree(sksec);
5314}
5315
5316static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5317{
5318 struct sk_security_struct *sksec = sk->sk_security;
5319 struct sk_security_struct *newsksec = newsk->sk_security;
5320
5321 newsksec->sid = sksec->sid;
5322 newsksec->peer_sid = sksec->peer_sid;
5323 newsksec->sclass = sksec->sclass;
5324
5325 selinux_netlbl_sk_security_reset(newsksec);
5326}
5327
5328static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5329{
5330 if (!sk)
5331 *secid = SECINITSID_ANY_SOCKET;
5332 else {
5333 struct sk_security_struct *sksec = sk->sk_security;
5334
5335 *secid = sksec->sid;
5336 }
5337}
5338
5339static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5340{
5341 struct inode_security_struct *isec =
5342 inode_security_novalidate(SOCK_INODE(parent));
5343 struct sk_security_struct *sksec = sk->sk_security;
5344
5345 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5346 sk->sk_family == PF_UNIX)
5347 isec->sid = sksec->sid;
5348 sksec->sclass = isec->sclass;
5349}
5350
5351/* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5352 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5353 * already present).
5354 */
5355static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5356 struct sk_buff *skb)
5357{
5358 struct sk_security_struct *sksec = ep->base.sk->sk_security;
5359 struct common_audit_data ad;
5360 struct lsm_network_audit net = {0,};
5361 u8 peerlbl_active;
5362 u32 peer_sid = SECINITSID_UNLABELED;
5363 u32 conn_sid;
5364 int err = 0;
5365
5366 if (!selinux_policycap_extsockclass())
5367 return 0;
5368
5369 peerlbl_active = selinux_peerlbl_enabled();
5370
5371 if (peerlbl_active) {
5372 /* This will return peer_sid = SECSID_NULL if there are
5373 * no peer labels, see security_net_peersid_resolve().
5374 */
5375 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5376 &peer_sid);
5377 if (err)
5378 return err;
5379
5380 if (peer_sid == SECSID_NULL)
5381 peer_sid = SECINITSID_UNLABELED;
5382 }
5383
5384 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5385 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5386
5387 /* Here as first association on socket. As the peer SID
5388 * was allowed by peer recv (and the netif/node checks),
5389 * then it is approved by policy and used as the primary
5390 * peer SID for getpeercon(3).
5391 */
5392 sksec->peer_sid = peer_sid;
5393 } else if (sksec->peer_sid != peer_sid) {
5394 /* Other association peer SIDs are checked to enforce
5395 * consistency among the peer SIDs.
5396 */
5397 ad.type = LSM_AUDIT_DATA_NET;
5398 ad.u.net = &net;
5399 ad.u.net->sk = ep->base.sk;
5400 err = avc_has_perm(&selinux_state,
5401 sksec->peer_sid, peer_sid, sksec->sclass,
5402 SCTP_SOCKET__ASSOCIATION, &ad);
5403 if (err)
5404 return err;
5405 }
5406
5407 /* Compute the MLS component for the connection and store
5408 * the information in ep. This will be used by SCTP TCP type
5409 * sockets and peeled off connections as they cause a new
5410 * socket to be generated. selinux_sctp_sk_clone() will then
5411 * plug this into the new socket.
5412 */
5413 err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5414 if (err)
5415 return err;
5416
5417 ep->secid = conn_sid;
5418 ep->peer_secid = peer_sid;
5419
5420 /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5421 return selinux_netlbl_sctp_assoc_request(ep, skb);
5422}
5423
5424/* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5425 * based on their @optname.
5426 */
5427static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5428 struct sockaddr *address,
5429 int addrlen)
5430{
5431 int len, err = 0, walk_size = 0;
5432 void *addr_buf;
5433 struct sockaddr *addr;
5434 struct socket *sock;
5435
5436 if (!selinux_policycap_extsockclass())
5437 return 0;
5438
5439 /* Process one or more addresses that may be IPv4 or IPv6 */
5440 sock = sk->sk_socket;
5441 addr_buf = address;
5442
5443 while (walk_size < addrlen) {
5444 if (walk_size + sizeof(sa_family_t) > addrlen)
5445 return -EINVAL;
5446
5447 addr = addr_buf;
5448 switch (addr->sa_family) {
5449 case AF_UNSPEC:
5450 case AF_INET:
5451 len = sizeof(struct sockaddr_in);
5452 break;
5453 case AF_INET6:
5454 len = sizeof(struct sockaddr_in6);
5455 break;
5456 default:
5457 return -EINVAL;
5458 }
5459
5460 if (walk_size + len > addrlen)
5461 return -EINVAL;
5462
5463 err = -EINVAL;
5464 switch (optname) {
5465 /* Bind checks */
5466 case SCTP_PRIMARY_ADDR:
5467 case SCTP_SET_PEER_PRIMARY_ADDR:
5468 case SCTP_SOCKOPT_BINDX_ADD:
5469 err = selinux_socket_bind(sock, addr, len);
5470 break;
5471 /* Connect checks */
5472 case SCTP_SOCKOPT_CONNECTX:
5473 case SCTP_PARAM_SET_PRIMARY:
5474 case SCTP_PARAM_ADD_IP:
5475 case SCTP_SENDMSG_CONNECT:
5476 err = selinux_socket_connect_helper(sock, addr, len);
5477 if (err)
5478 return err;
5479
5480 /* As selinux_sctp_bind_connect() is called by the
5481 * SCTP protocol layer, the socket is already locked,
5482 * therefore selinux_netlbl_socket_connect_locked()
5483 * is called here. The situations handled are:
5484 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5485 * whenever a new IP address is added or when a new
5486 * primary address is selected.
5487 * Note that an SCTP connect(2) call happens before
5488 * the SCTP protocol layer and is handled via
5489 * selinux_socket_connect().
5490 */
5491 err = selinux_netlbl_socket_connect_locked(sk, addr);
5492 break;
5493 }
5494
5495 if (err)
5496 return err;
5497
5498 addr_buf += len;
5499 walk_size += len;
5500 }
5501
5502 return 0;
5503}
5504
5505/* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5506static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5507 struct sock *newsk)
5508{
5509 struct sk_security_struct *sksec = sk->sk_security;
5510 struct sk_security_struct *newsksec = newsk->sk_security;
5511
5512 /* If policy does not support SECCLASS_SCTP_SOCKET then call
5513 * the non-sctp clone version.
5514 */
5515 if (!selinux_policycap_extsockclass())
5516 return selinux_sk_clone_security(sk, newsk);
5517
5518 newsksec->sid = ep->secid;
5519 newsksec->peer_sid = ep->peer_secid;
5520 newsksec->sclass = sksec->sclass;
5521 selinux_netlbl_sctp_sk_clone(sk, newsk);
5522}
5523
5524static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5525 struct request_sock *req)
5526{
5527 struct sk_security_struct *sksec = sk->sk_security;
5528 int err;
5529 u16 family = req->rsk_ops->family;
5530 u32 connsid;
5531 u32 peersid;
5532
5533 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5534 if (err)
5535 return err;
5536 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5537 if (err)
5538 return err;
5539 req->secid = connsid;
5540 req->peer_secid = peersid;
5541
5542 return selinux_netlbl_inet_conn_request(req, family);
5543}
5544
5545static void selinux_inet_csk_clone(struct sock *newsk,
5546 const struct request_sock *req)
5547{
5548 struct sk_security_struct *newsksec = newsk->sk_security;
5549
5550 newsksec->sid = req->secid;
5551 newsksec->peer_sid = req->peer_secid;
5552 /* NOTE: Ideally, we should also get the isec->sid for the
5553 new socket in sync, but we don't have the isec available yet.
5554 So we will wait until sock_graft to do it, by which
5555 time it will have been created and available. */
5556
5557 /* We don't need to take any sort of lock here as we are the only
5558 * thread with access to newsksec */
5559 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5560}
5561
5562static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5563{
5564 u16 family = sk->sk_family;
5565 struct sk_security_struct *sksec = sk->sk_security;
5566
5567 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5568 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5569 family = PF_INET;
5570
5571 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5572}
5573
5574static int selinux_secmark_relabel_packet(u32 sid)
5575{
5576 const struct task_security_struct *__tsec;
5577 u32 tsid;
5578
5579 __tsec = selinux_cred(current_cred());
5580 tsid = __tsec->sid;
5581
5582 return avc_has_perm(&selinux_state,
5583 tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5584 NULL);
5585}
5586
5587static void selinux_secmark_refcount_inc(void)
5588{
5589 atomic_inc(&selinux_secmark_refcount);
5590}
5591
5592static void selinux_secmark_refcount_dec(void)
5593{
5594 atomic_dec(&selinux_secmark_refcount);
5595}
5596
5597static void selinux_req_classify_flow(const struct request_sock *req,
5598 struct flowi_common *flic)
5599{
5600 flic->flowic_secid = req->secid;
5601}
5602
5603static int selinux_tun_dev_alloc_security(void **security)
5604{
5605 struct tun_security_struct *tunsec;
5606
5607 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5608 if (!tunsec)
5609 return -ENOMEM;
5610 tunsec->sid = current_sid();
5611
5612 *security = tunsec;
5613 return 0;
5614}
5615
5616static void selinux_tun_dev_free_security(void *security)
5617{
5618 kfree(security);
5619}
5620
5621static int selinux_tun_dev_create(void)
5622{
5623 u32 sid = current_sid();
5624
5625 /* we aren't taking into account the "sockcreate" SID since the socket
5626 * that is being created here is not a socket in the traditional sense,
5627 * instead it is a private sock, accessible only to the kernel, and
5628 * representing a wide range of network traffic spanning multiple
5629 * connections unlike traditional sockets - check the TUN driver to
5630 * get a better understanding of why this socket is special */
5631
5632 return avc_has_perm(&selinux_state,
5633 sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5634 NULL);
5635}
5636
5637static int selinux_tun_dev_attach_queue(void *security)
5638{
5639 struct tun_security_struct *tunsec = security;
5640
5641 return avc_has_perm(&selinux_state,
5642 current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5643 TUN_SOCKET__ATTACH_QUEUE, NULL);
5644}
5645
5646static int selinux_tun_dev_attach(struct sock *sk, void *security)
5647{
5648 struct tun_security_struct *tunsec = security;
5649 struct sk_security_struct *sksec = sk->sk_security;
5650
5651 /* we don't currently perform any NetLabel based labeling here and it
5652 * isn't clear that we would want to do so anyway; while we could apply
5653 * labeling without the support of the TUN user the resulting labeled
5654 * traffic from the other end of the connection would almost certainly
5655 * cause confusion to the TUN user that had no idea network labeling
5656 * protocols were being used */
5657
5658 sksec->sid = tunsec->sid;
5659 sksec->sclass = SECCLASS_TUN_SOCKET;
5660
5661 return 0;
5662}
5663
5664static int selinux_tun_dev_open(void *security)
5665{
5666 struct tun_security_struct *tunsec = security;
5667 u32 sid = current_sid();
5668 int err;
5669
5670 err = avc_has_perm(&selinux_state,
5671 sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5672 TUN_SOCKET__RELABELFROM, NULL);
5673 if (err)
5674 return err;
5675 err = avc_has_perm(&selinux_state,
5676 sid, sid, SECCLASS_TUN_SOCKET,
5677 TUN_SOCKET__RELABELTO, NULL);
5678 if (err)
5679 return err;
5680 tunsec->sid = sid;
5681
5682 return 0;
5683}
5684
5685#ifdef CONFIG_NETFILTER
5686
5687static unsigned int selinux_ip_forward(struct sk_buff *skb,
5688 const struct net_device *indev,
5689 u16 family)
5690{
5691 int err;
5692 char *addrp;
5693 u32 peer_sid;
5694 struct common_audit_data ad;
5695 struct lsm_network_audit net = {0,};
5696 u8 secmark_active;
5697 u8 netlbl_active;
5698 u8 peerlbl_active;
5699
5700 if (!selinux_policycap_netpeer())
5701 return NF_ACCEPT;
5702
5703 secmark_active = selinux_secmark_enabled();
5704 netlbl_active = netlbl_enabled();
5705 peerlbl_active = selinux_peerlbl_enabled();
5706 if (!secmark_active && !peerlbl_active)
5707 return NF_ACCEPT;
5708
5709 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5710 return NF_DROP;
5711
5712 ad.type = LSM_AUDIT_DATA_NET;
5713 ad.u.net = &net;
5714 ad.u.net->netif = indev->ifindex;
5715 ad.u.net->family = family;
5716 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5717 return NF_DROP;
5718
5719 if (peerlbl_active) {
5720 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5721 addrp, family, peer_sid, &ad);
5722 if (err) {
5723 selinux_netlbl_err(skb, family, err, 1);
5724 return NF_DROP;
5725 }
5726 }
5727
5728 if (secmark_active)
5729 if (avc_has_perm(&selinux_state,
5730 peer_sid, skb->secmark,
5731 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5732 return NF_DROP;
5733
5734 if (netlbl_active)
5735 /* we do this in the FORWARD path and not the POST_ROUTING
5736 * path because we want to make sure we apply the necessary
5737 * labeling before IPsec is applied so we can leverage AH
5738 * protection */
5739 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5740 return NF_DROP;
5741
5742 return NF_ACCEPT;
5743}
5744
5745static unsigned int selinux_ipv4_forward(void *priv,
5746 struct sk_buff *skb,
5747 const struct nf_hook_state *state)
5748{
5749 return selinux_ip_forward(skb, state->in, PF_INET);
5750}
5751
5752#if IS_ENABLED(CONFIG_IPV6)
5753static unsigned int selinux_ipv6_forward(void *priv,
5754 struct sk_buff *skb,
5755 const struct nf_hook_state *state)
5756{
5757 return selinux_ip_forward(skb, state->in, PF_INET6);
5758}
5759#endif /* IPV6 */
5760
5761static unsigned int selinux_ip_output(struct sk_buff *skb,
5762 u16 family)
5763{
5764 struct sock *sk;
5765 u32 sid;
5766
5767 if (!netlbl_enabled())
5768 return NF_ACCEPT;
5769
5770 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5771 * because we want to make sure we apply the necessary labeling
5772 * before IPsec is applied so we can leverage AH protection */
5773 sk = skb->sk;
5774 if (sk) {
5775 struct sk_security_struct *sksec;
5776
5777 if (sk_listener(sk))
5778 /* if the socket is the listening state then this
5779 * packet is a SYN-ACK packet which means it needs to
5780 * be labeled based on the connection/request_sock and
5781 * not the parent socket. unfortunately, we can't
5782 * lookup the request_sock yet as it isn't queued on
5783 * the parent socket until after the SYN-ACK is sent.
5784 * the "solution" is to simply pass the packet as-is
5785 * as any IP option based labeling should be copied
5786 * from the initial connection request (in the IP
5787 * layer). it is far from ideal, but until we get a
5788 * security label in the packet itself this is the
5789 * best we can do. */
5790 return NF_ACCEPT;
5791
5792 /* standard practice, label using the parent socket */
5793 sksec = sk->sk_security;
5794 sid = sksec->sid;
5795 } else
5796 sid = SECINITSID_KERNEL;
5797 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5798 return NF_DROP;
5799
5800 return NF_ACCEPT;
5801}
5802
5803static unsigned int selinux_ipv4_output(void *priv,
5804 struct sk_buff *skb,
5805 const struct nf_hook_state *state)
5806{
5807 return selinux_ip_output(skb, PF_INET);
5808}
5809
5810#if IS_ENABLED(CONFIG_IPV6)
5811static unsigned int selinux_ipv6_output(void *priv,
5812 struct sk_buff *skb,
5813 const struct nf_hook_state *state)
5814{
5815 return selinux_ip_output(skb, PF_INET6);
5816}
5817#endif /* IPV6 */
5818
5819static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5820 int ifindex,
5821 u16 family)
5822{
5823 struct sock *sk = skb_to_full_sk(skb);
5824 struct sk_security_struct *sksec;
5825 struct common_audit_data ad;
5826 struct lsm_network_audit net = {0,};
5827 char *addrp;
5828 u8 proto;
5829
5830 if (sk == NULL)
5831 return NF_ACCEPT;
5832 sksec = sk->sk_security;
5833
5834 ad.type = LSM_AUDIT_DATA_NET;
5835 ad.u.net = &net;
5836 ad.u.net->netif = ifindex;
5837 ad.u.net->family = family;
5838 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5839 return NF_DROP;
5840
5841 if (selinux_secmark_enabled())
5842 if (avc_has_perm(&selinux_state,
5843 sksec->sid, skb->secmark,
5844 SECCLASS_PACKET, PACKET__SEND, &ad))
5845 return NF_DROP_ERR(-ECONNREFUSED);
5846
5847 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5848 return NF_DROP_ERR(-ECONNREFUSED);
5849
5850 return NF_ACCEPT;
5851}
5852
5853static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5854 const struct net_device *outdev,
5855 u16 family)
5856{
5857 u32 secmark_perm;
5858 u32 peer_sid;
5859 int ifindex = outdev->ifindex;
5860 struct sock *sk;
5861 struct common_audit_data ad;
5862 struct lsm_network_audit net = {0,};
5863 char *addrp;
5864 u8 secmark_active;
5865 u8 peerlbl_active;
5866
5867 /* If any sort of compatibility mode is enabled then handoff processing
5868 * to the selinux_ip_postroute_compat() function to deal with the
5869 * special handling. We do this in an attempt to keep this function
5870 * as fast and as clean as possible. */
5871 if (!selinux_policycap_netpeer())
5872 return selinux_ip_postroute_compat(skb, ifindex, family);
5873
5874 secmark_active = selinux_secmark_enabled();
5875 peerlbl_active = selinux_peerlbl_enabled();
5876 if (!secmark_active && !peerlbl_active)
5877 return NF_ACCEPT;
5878
5879 sk = skb_to_full_sk(skb);
5880
5881#ifdef CONFIG_XFRM
5882 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5883 * packet transformation so allow the packet to pass without any checks
5884 * since we'll have another chance to perform access control checks
5885 * when the packet is on it's final way out.
5886 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5887 * is NULL, in this case go ahead and apply access control.
5888 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5889 * TCP listening state we cannot wait until the XFRM processing
5890 * is done as we will miss out on the SA label if we do;
5891 * unfortunately, this means more work, but it is only once per
5892 * connection. */
5893 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5894 !(sk && sk_listener(sk)))
5895 return NF_ACCEPT;
5896#endif
5897
5898 if (sk == NULL) {
5899 /* Without an associated socket the packet is either coming
5900 * from the kernel or it is being forwarded; check the packet
5901 * to determine which and if the packet is being forwarded
5902 * query the packet directly to determine the security label. */
5903 if (skb->skb_iif) {
5904 secmark_perm = PACKET__FORWARD_OUT;
5905 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5906 return NF_DROP;
5907 } else {
5908 secmark_perm = PACKET__SEND;
5909 peer_sid = SECINITSID_KERNEL;
5910 }
5911 } else if (sk_listener(sk)) {
5912 /* Locally generated packet but the associated socket is in the
5913 * listening state which means this is a SYN-ACK packet. In
5914 * this particular case the correct security label is assigned
5915 * to the connection/request_sock but unfortunately we can't
5916 * query the request_sock as it isn't queued on the parent
5917 * socket until after the SYN-ACK packet is sent; the only
5918 * viable choice is to regenerate the label like we do in
5919 * selinux_inet_conn_request(). See also selinux_ip_output()
5920 * for similar problems. */
5921 u32 skb_sid;
5922 struct sk_security_struct *sksec;
5923
5924 sksec = sk->sk_security;
5925 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5926 return NF_DROP;
5927 /* At this point, if the returned skb peerlbl is SECSID_NULL
5928 * and the packet has been through at least one XFRM
5929 * transformation then we must be dealing with the "final"
5930 * form of labeled IPsec packet; since we've already applied
5931 * all of our access controls on this packet we can safely
5932 * pass the packet. */
5933 if (skb_sid == SECSID_NULL) {
5934 switch (family) {
5935 case PF_INET:
5936 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5937 return NF_ACCEPT;
5938 break;
5939 case PF_INET6:
5940 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5941 return NF_ACCEPT;
5942 break;
5943 default:
5944 return NF_DROP_ERR(-ECONNREFUSED);
5945 }
5946 }
5947 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5948 return NF_DROP;
5949 secmark_perm = PACKET__SEND;
5950 } else {
5951 /* Locally generated packet, fetch the security label from the
5952 * associated socket. */
5953 struct sk_security_struct *sksec = sk->sk_security;
5954 peer_sid = sksec->sid;
5955 secmark_perm = PACKET__SEND;
5956 }
5957
5958 ad.type = LSM_AUDIT_DATA_NET;
5959 ad.u.net = &net;
5960 ad.u.net->netif = ifindex;
5961 ad.u.net->family = family;
5962 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5963 return NF_DROP;
5964
5965 if (secmark_active)
5966 if (avc_has_perm(&selinux_state,
5967 peer_sid, skb->secmark,
5968 SECCLASS_PACKET, secmark_perm, &ad))
5969 return NF_DROP_ERR(-ECONNREFUSED);
5970
5971 if (peerlbl_active) {
5972 u32 if_sid;
5973 u32 node_sid;
5974
5975 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5976 return NF_DROP;
5977 if (avc_has_perm(&selinux_state,
5978 peer_sid, if_sid,
5979 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5980 return NF_DROP_ERR(-ECONNREFUSED);
5981
5982 if (sel_netnode_sid(addrp, family, &node_sid))
5983 return NF_DROP;
5984 if (avc_has_perm(&selinux_state,
5985 peer_sid, node_sid,
5986 SECCLASS_NODE, NODE__SENDTO, &ad))
5987 return NF_DROP_ERR(-ECONNREFUSED);
5988 }
5989
5990 return NF_ACCEPT;
5991}
5992
5993static unsigned int selinux_ipv4_postroute(void *priv,
5994 struct sk_buff *skb,
5995 const struct nf_hook_state *state)
5996{
5997 return selinux_ip_postroute(skb, state->out, PF_INET);
5998}
5999
6000#if IS_ENABLED(CONFIG_IPV6)
6001static unsigned int selinux_ipv6_postroute(void *priv,
6002 struct sk_buff *skb,
6003 const struct nf_hook_state *state)
6004{
6005 return selinux_ip_postroute(skb, state->out, PF_INET6);
6006}
6007#endif /* IPV6 */
6008
6009#endif /* CONFIG_NETFILTER */
6010
6011static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
6012{
6013 int rc = 0;
6014 unsigned int msg_len;
6015 unsigned int data_len = skb->len;
6016 unsigned char *data = skb->data;
6017 struct nlmsghdr *nlh;
6018 struct sk_security_struct *sksec = sk->sk_security;
6019 u16 sclass = sksec->sclass;
6020 u32 perm;
6021
6022 while (data_len >= nlmsg_total_size(0)) {
6023 nlh = (struct nlmsghdr *)data;
6024
6025 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
6026 * users which means we can't reject skb's with bogus
6027 * length fields; our solution is to follow what
6028 * netlink_rcv_skb() does and simply skip processing at
6029 * messages with length fields that are clearly junk
6030 */
6031 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
6032 return 0;
6033
6034 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
6035 if (rc == 0) {
6036 rc = sock_has_perm(sk, perm);
6037 if (rc)
6038 return rc;
6039 } else if (rc == -EINVAL) {
6040 /* -EINVAL is a missing msg/perm mapping */
6041 pr_warn_ratelimited("SELinux: unrecognized netlink"
6042 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
6043 " pid=%d comm=%s\n",
6044 sk->sk_protocol, nlh->nlmsg_type,
6045 secclass_map[sclass - 1].name,
6046 task_pid_nr(current), current->comm);
6047 if (enforcing_enabled(&selinux_state) &&
6048 !security_get_allow_unknown(&selinux_state))
6049 return rc;
6050 rc = 0;
6051 } else if (rc == -ENOENT) {
6052 /* -ENOENT is a missing socket/class mapping, ignore */
6053 rc = 0;
6054 } else {
6055 return rc;
6056 }
6057
6058 /* move to the next message after applying netlink padding */
6059 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
6060 if (msg_len >= data_len)
6061 return 0;
6062 data_len -= msg_len;
6063 data += msg_len;
6064 }
6065
6066 return rc;
6067}
6068
6069static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
6070{
6071 isec->sclass = sclass;
6072 isec->sid = current_sid();
6073}
6074
6075static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
6076 u32 perms)
6077{
6078 struct ipc_security_struct *isec;
6079 struct common_audit_data ad;
6080 u32 sid = current_sid();
6081
6082 isec = selinux_ipc(ipc_perms);
6083
6084 ad.type = LSM_AUDIT_DATA_IPC;
6085 ad.u.ipc_id = ipc_perms->key;
6086
6087 return avc_has_perm(&selinux_state,
6088 sid, isec->sid, isec->sclass, perms, &ad);
6089}
6090
6091static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6092{
6093 struct msg_security_struct *msec;
6094
6095 msec = selinux_msg_msg(msg);
6096 msec->sid = SECINITSID_UNLABELED;
6097
6098 return 0;
6099}
6100
6101/* message queue security operations */
6102static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6103{
6104 struct ipc_security_struct *isec;
6105 struct common_audit_data ad;
6106 u32 sid = current_sid();
6107 int rc;
6108
6109 isec = selinux_ipc(msq);
6110 ipc_init_security(isec, SECCLASS_MSGQ);
6111
6112 ad.type = LSM_AUDIT_DATA_IPC;
6113 ad.u.ipc_id = msq->key;
6114
6115 rc = avc_has_perm(&selinux_state,
6116 sid, isec->sid, SECCLASS_MSGQ,
6117 MSGQ__CREATE, &ad);
6118 return rc;
6119}
6120
6121static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6122{
6123 struct ipc_security_struct *isec;
6124 struct common_audit_data ad;
6125 u32 sid = current_sid();
6126
6127 isec = selinux_ipc(msq);
6128
6129 ad.type = LSM_AUDIT_DATA_IPC;
6130 ad.u.ipc_id = msq->key;
6131
6132 return avc_has_perm(&selinux_state,
6133 sid, isec->sid, SECCLASS_MSGQ,
6134 MSGQ__ASSOCIATE, &ad);
6135}
6136
6137static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6138{
6139 int err;
6140 int perms;
6141
6142 switch (cmd) {
6143 case IPC_INFO:
6144 case MSG_INFO:
6145 /* No specific object, just general system-wide information. */
6146 return avc_has_perm(&selinux_state,
6147 current_sid(), SECINITSID_KERNEL,
6148 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6149 case IPC_STAT:
6150 case MSG_STAT:
6151 case MSG_STAT_ANY:
6152 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6153 break;
6154 case IPC_SET:
6155 perms = MSGQ__SETATTR;
6156 break;
6157 case IPC_RMID:
6158 perms = MSGQ__DESTROY;
6159 break;
6160 default:
6161 return 0;
6162 }
6163
6164 err = ipc_has_perm(msq, perms);
6165 return err;
6166}
6167
6168static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6169{
6170 struct ipc_security_struct *isec;
6171 struct msg_security_struct *msec;
6172 struct common_audit_data ad;
6173 u32 sid = current_sid();
6174 int rc;
6175
6176 isec = selinux_ipc(msq);
6177 msec = selinux_msg_msg(msg);
6178
6179 /*
6180 * First time through, need to assign label to the message
6181 */
6182 if (msec->sid == SECINITSID_UNLABELED) {
6183 /*
6184 * Compute new sid based on current process and
6185 * message queue this message will be stored in
6186 */
6187 rc = security_transition_sid(&selinux_state, sid, isec->sid,
6188 SECCLASS_MSG, NULL, &msec->sid);
6189 if (rc)
6190 return rc;
6191 }
6192
6193 ad.type = LSM_AUDIT_DATA_IPC;
6194 ad.u.ipc_id = msq->key;
6195
6196 /* Can this process write to the queue? */
6197 rc = avc_has_perm(&selinux_state,
6198 sid, isec->sid, SECCLASS_MSGQ,
6199 MSGQ__WRITE, &ad);
6200 if (!rc)
6201 /* Can this process send the message */
6202 rc = avc_has_perm(&selinux_state,
6203 sid, msec->sid, SECCLASS_MSG,
6204 MSG__SEND, &ad);
6205 if (!rc)
6206 /* Can the message be put in the queue? */
6207 rc = avc_has_perm(&selinux_state,
6208 msec->sid, isec->sid, SECCLASS_MSGQ,
6209 MSGQ__ENQUEUE, &ad);
6210
6211 return rc;
6212}
6213
6214static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6215 struct task_struct *target,
6216 long type, int mode)
6217{
6218 struct ipc_security_struct *isec;
6219 struct msg_security_struct *msec;
6220 struct common_audit_data ad;
6221 u32 sid = task_sid_obj(target);
6222 int rc;
6223
6224 isec = selinux_ipc(msq);
6225 msec = selinux_msg_msg(msg);
6226
6227 ad.type = LSM_AUDIT_DATA_IPC;
6228 ad.u.ipc_id = msq->key;
6229
6230 rc = avc_has_perm(&selinux_state,
6231 sid, isec->sid,
6232 SECCLASS_MSGQ, MSGQ__READ, &ad);
6233 if (!rc)
6234 rc = avc_has_perm(&selinux_state,
6235 sid, msec->sid,
6236 SECCLASS_MSG, MSG__RECEIVE, &ad);
6237 return rc;
6238}
6239
6240/* Shared Memory security operations */
6241static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6242{
6243 struct ipc_security_struct *isec;
6244 struct common_audit_data ad;
6245 u32 sid = current_sid();
6246 int rc;
6247
6248 isec = selinux_ipc(shp);
6249 ipc_init_security(isec, SECCLASS_SHM);
6250
6251 ad.type = LSM_AUDIT_DATA_IPC;
6252 ad.u.ipc_id = shp->key;
6253
6254 rc = avc_has_perm(&selinux_state,
6255 sid, isec->sid, SECCLASS_SHM,
6256 SHM__CREATE, &ad);
6257 return rc;
6258}
6259
6260static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6261{
6262 struct ipc_security_struct *isec;
6263 struct common_audit_data ad;
6264 u32 sid = current_sid();
6265
6266 isec = selinux_ipc(shp);
6267
6268 ad.type = LSM_AUDIT_DATA_IPC;
6269 ad.u.ipc_id = shp->key;
6270
6271 return avc_has_perm(&selinux_state,
6272 sid, isec->sid, SECCLASS_SHM,
6273 SHM__ASSOCIATE, &ad);
6274}
6275
6276/* Note, at this point, shp is locked down */
6277static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6278{
6279 int perms;
6280 int err;
6281
6282 switch (cmd) {
6283 case IPC_INFO:
6284 case SHM_INFO:
6285 /* No specific object, just general system-wide information. */
6286 return avc_has_perm(&selinux_state,
6287 current_sid(), SECINITSID_KERNEL,
6288 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6289 case IPC_STAT:
6290 case SHM_STAT:
6291 case SHM_STAT_ANY:
6292 perms = SHM__GETATTR | SHM__ASSOCIATE;
6293 break;
6294 case IPC_SET:
6295 perms = SHM__SETATTR;
6296 break;
6297 case SHM_LOCK:
6298 case SHM_UNLOCK:
6299 perms = SHM__LOCK;
6300 break;
6301 case IPC_RMID:
6302 perms = SHM__DESTROY;
6303 break;
6304 default:
6305 return 0;
6306 }
6307
6308 err = ipc_has_perm(shp, perms);
6309 return err;
6310}
6311
6312static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6313 char __user *shmaddr, int shmflg)
6314{
6315 u32 perms;
6316
6317 if (shmflg & SHM_RDONLY)
6318 perms = SHM__READ;
6319 else
6320 perms = SHM__READ | SHM__WRITE;
6321
6322 return ipc_has_perm(shp, perms);
6323}
6324
6325/* Semaphore security operations */
6326static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6327{
6328 struct ipc_security_struct *isec;
6329 struct common_audit_data ad;
6330 u32 sid = current_sid();
6331 int rc;
6332
6333 isec = selinux_ipc(sma);
6334 ipc_init_security(isec, SECCLASS_SEM);
6335
6336 ad.type = LSM_AUDIT_DATA_IPC;
6337 ad.u.ipc_id = sma->key;
6338
6339 rc = avc_has_perm(&selinux_state,
6340 sid, isec->sid, SECCLASS_SEM,
6341 SEM__CREATE, &ad);
6342 return rc;
6343}
6344
6345static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6346{
6347 struct ipc_security_struct *isec;
6348 struct common_audit_data ad;
6349 u32 sid = current_sid();
6350
6351 isec = selinux_ipc(sma);
6352
6353 ad.type = LSM_AUDIT_DATA_IPC;
6354 ad.u.ipc_id = sma->key;
6355
6356 return avc_has_perm(&selinux_state,
6357 sid, isec->sid, SECCLASS_SEM,
6358 SEM__ASSOCIATE, &ad);
6359}
6360
6361/* Note, at this point, sma is locked down */
6362static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6363{
6364 int err;
6365 u32 perms;
6366
6367 switch (cmd) {
6368 case IPC_INFO:
6369 case SEM_INFO:
6370 /* No specific object, just general system-wide information. */
6371 return avc_has_perm(&selinux_state,
6372 current_sid(), SECINITSID_KERNEL,
6373 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6374 case GETPID:
6375 case GETNCNT:
6376 case GETZCNT:
6377 perms = SEM__GETATTR;
6378 break;
6379 case GETVAL:
6380 case GETALL:
6381 perms = SEM__READ;
6382 break;
6383 case SETVAL:
6384 case SETALL:
6385 perms = SEM__WRITE;
6386 break;
6387 case IPC_RMID:
6388 perms = SEM__DESTROY;
6389 break;
6390 case IPC_SET:
6391 perms = SEM__SETATTR;
6392 break;
6393 case IPC_STAT:
6394 case SEM_STAT:
6395 case SEM_STAT_ANY:
6396 perms = SEM__GETATTR | SEM__ASSOCIATE;
6397 break;
6398 default:
6399 return 0;
6400 }
6401
6402 err = ipc_has_perm(sma, perms);
6403 return err;
6404}
6405
6406static int selinux_sem_semop(struct kern_ipc_perm *sma,
6407 struct sembuf *sops, unsigned nsops, int alter)
6408{
6409 u32 perms;
6410
6411 if (alter)
6412 perms = SEM__READ | SEM__WRITE;
6413 else
6414 perms = SEM__READ;
6415
6416 return ipc_has_perm(sma, perms);
6417}
6418
6419static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6420{
6421 u32 av = 0;
6422
6423 av = 0;
6424 if (flag & S_IRUGO)
6425 av |= IPC__UNIX_READ;
6426 if (flag & S_IWUGO)
6427 av |= IPC__UNIX_WRITE;
6428
6429 if (av == 0)
6430 return 0;
6431
6432 return ipc_has_perm(ipcp, av);
6433}
6434
6435static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6436{
6437 struct ipc_security_struct *isec = selinux_ipc(ipcp);
6438 *secid = isec->sid;
6439}
6440
6441static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6442{
6443 if (inode)
6444 inode_doinit_with_dentry(inode, dentry);
6445}
6446
6447static int selinux_getprocattr(struct task_struct *p,
6448 char *name, char **value)
6449{
6450 const struct task_security_struct *__tsec;
6451 u32 sid;
6452 int error;
6453 unsigned len;
6454
6455 rcu_read_lock();
6456 __tsec = selinux_cred(__task_cred(p));
6457
6458 if (current != p) {
6459 error = avc_has_perm(&selinux_state,
6460 current_sid(), __tsec->sid,
6461 SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6462 if (error)
6463 goto bad;
6464 }
6465
6466 if (!strcmp(name, "current"))
6467 sid = __tsec->sid;
6468 else if (!strcmp(name, "prev"))
6469 sid = __tsec->osid;
6470 else if (!strcmp(name, "exec"))
6471 sid = __tsec->exec_sid;
6472 else if (!strcmp(name, "fscreate"))
6473 sid = __tsec->create_sid;
6474 else if (!strcmp(name, "keycreate"))
6475 sid = __tsec->keycreate_sid;
6476 else if (!strcmp(name, "sockcreate"))
6477 sid = __tsec->sockcreate_sid;
6478 else {
6479 error = -EINVAL;
6480 goto bad;
6481 }
6482 rcu_read_unlock();
6483
6484 if (!sid)
6485 return 0;
6486
6487 error = security_sid_to_context(&selinux_state, sid, value, &len);
6488 if (error)
6489 return error;
6490 return len;
6491
6492bad:
6493 rcu_read_unlock();
6494 return error;
6495}
6496
6497static int selinux_setprocattr(const char *name, void *value, size_t size)
6498{
6499 struct task_security_struct *tsec;
6500 struct cred *new;
6501 u32 mysid = current_sid(), sid = 0, ptsid;
6502 int error;
6503 char *str = value;
6504
6505 /*
6506 * Basic control over ability to set these attributes at all.
6507 */
6508 if (!strcmp(name, "exec"))
6509 error = avc_has_perm(&selinux_state,
6510 mysid, mysid, SECCLASS_PROCESS,
6511 PROCESS__SETEXEC, NULL);
6512 else if (!strcmp(name, "fscreate"))
6513 error = avc_has_perm(&selinux_state,
6514 mysid, mysid, SECCLASS_PROCESS,
6515 PROCESS__SETFSCREATE, NULL);
6516 else if (!strcmp(name, "keycreate"))
6517 error = avc_has_perm(&selinux_state,
6518 mysid, mysid, SECCLASS_PROCESS,
6519 PROCESS__SETKEYCREATE, NULL);
6520 else if (!strcmp(name, "sockcreate"))
6521 error = avc_has_perm(&selinux_state,
6522 mysid, mysid, SECCLASS_PROCESS,
6523 PROCESS__SETSOCKCREATE, NULL);
6524 else if (!strcmp(name, "current"))
6525 error = avc_has_perm(&selinux_state,
6526 mysid, mysid, SECCLASS_PROCESS,
6527 PROCESS__SETCURRENT, NULL);
6528 else
6529 error = -EINVAL;
6530 if (error)
6531 return error;
6532
6533 /* Obtain a SID for the context, if one was specified. */
6534 if (size && str[0] && str[0] != '\n') {
6535 if (str[size-1] == '\n') {
6536 str[size-1] = 0;
6537 size--;
6538 }
6539 error = security_context_to_sid(&selinux_state, value, size,
6540 &sid, GFP_KERNEL);
6541 if (error == -EINVAL && !strcmp(name, "fscreate")) {
6542 if (!has_cap_mac_admin(true)) {
6543 struct audit_buffer *ab;
6544 size_t audit_size;
6545
6546 /* We strip a nul only if it is at the end, otherwise the
6547 * context contains a nul and we should audit that */
6548 if (str[size - 1] == '\0')
6549 audit_size = size - 1;
6550 else
6551 audit_size = size;
6552 ab = audit_log_start(audit_context(),
6553 GFP_ATOMIC,
6554 AUDIT_SELINUX_ERR);
6555 audit_log_format(ab, "op=fscreate invalid_context=");
6556 audit_log_n_untrustedstring(ab, value, audit_size);
6557 audit_log_end(ab);
6558
6559 return error;
6560 }
6561 error = security_context_to_sid_force(
6562 &selinux_state,
6563 value, size, &sid);
6564 }
6565 if (error)
6566 return error;
6567 }
6568
6569 new = prepare_creds();
6570 if (!new)
6571 return -ENOMEM;
6572
6573 /* Permission checking based on the specified context is
6574 performed during the actual operation (execve,
6575 open/mkdir/...), when we know the full context of the
6576 operation. See selinux_bprm_creds_for_exec for the execve
6577 checks and may_create for the file creation checks. The
6578 operation will then fail if the context is not permitted. */
6579 tsec = selinux_cred(new);
6580 if (!strcmp(name, "exec")) {
6581 tsec->exec_sid = sid;
6582 } else if (!strcmp(name, "fscreate")) {
6583 tsec->create_sid = sid;
6584 } else if (!strcmp(name, "keycreate")) {
6585 if (sid) {
6586 error = avc_has_perm(&selinux_state, mysid, sid,
6587 SECCLASS_KEY, KEY__CREATE, NULL);
6588 if (error)
6589 goto abort_change;
6590 }
6591 tsec->keycreate_sid = sid;
6592 } else if (!strcmp(name, "sockcreate")) {
6593 tsec->sockcreate_sid = sid;
6594 } else if (!strcmp(name, "current")) {
6595 error = -EINVAL;
6596 if (sid == 0)
6597 goto abort_change;
6598
6599 /* Only allow single threaded processes to change context */
6600 error = -EPERM;
6601 if (!current_is_single_threaded()) {
6602 error = security_bounded_transition(&selinux_state,
6603 tsec->sid, sid);
6604 if (error)
6605 goto abort_change;
6606 }
6607
6608 /* Check permissions for the transition. */
6609 error = avc_has_perm(&selinux_state,
6610 tsec->sid, sid, SECCLASS_PROCESS,
6611 PROCESS__DYNTRANSITION, NULL);
6612 if (error)
6613 goto abort_change;
6614
6615 /* Check for ptracing, and update the task SID if ok.
6616 Otherwise, leave SID unchanged and fail. */
6617 ptsid = ptrace_parent_sid();
6618 if (ptsid != 0) {
6619 error = avc_has_perm(&selinux_state,
6620 ptsid, sid, SECCLASS_PROCESS,
6621 PROCESS__PTRACE, NULL);
6622 if (error)
6623 goto abort_change;
6624 }
6625
6626 tsec->sid = sid;
6627 } else {
6628 error = -EINVAL;
6629 goto abort_change;
6630 }
6631
6632 commit_creds(new);
6633 return size;
6634
6635abort_change:
6636 abort_creds(new);
6637 return error;
6638}
6639
6640static int selinux_ismaclabel(const char *name)
6641{
6642 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6643}
6644
6645static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6646{
6647 return security_sid_to_context(&selinux_state, secid,
6648 secdata, seclen);
6649}
6650
6651static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6652{
6653 return security_context_to_sid(&selinux_state, secdata, seclen,
6654 secid, GFP_KERNEL);
6655}
6656
6657static void selinux_release_secctx(char *secdata, u32 seclen)
6658{
6659 kfree(secdata);
6660}
6661
6662static void selinux_inode_invalidate_secctx(struct inode *inode)
6663{
6664 struct inode_security_struct *isec = selinux_inode(inode);
6665
6666 spin_lock(&isec->lock);
6667 isec->initialized = LABEL_INVALID;
6668 spin_unlock(&isec->lock);
6669}
6670
6671/*
6672 * called with inode->i_mutex locked
6673 */
6674static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6675{
6676 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6677 ctx, ctxlen, 0);
6678 /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6679 return rc == -EOPNOTSUPP ? 0 : rc;
6680}
6681
6682/*
6683 * called with inode->i_mutex locked
6684 */
6685static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6686{
6687 return __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_SELINUX,
6688 ctx, ctxlen, 0);
6689}
6690
6691static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6692{
6693 int len = 0;
6694 len = selinux_inode_getsecurity(&init_user_ns, inode,
6695 XATTR_SELINUX_SUFFIX, ctx, true);
6696 if (len < 0)
6697 return len;
6698 *ctxlen = len;
6699 return 0;
6700}
6701#ifdef CONFIG_KEYS
6702
6703static int selinux_key_alloc(struct key *k, const struct cred *cred,
6704 unsigned long flags)
6705{
6706 const struct task_security_struct *tsec;
6707 struct key_security_struct *ksec;
6708
6709 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6710 if (!ksec)
6711 return -ENOMEM;
6712
6713 tsec = selinux_cred(cred);
6714 if (tsec->keycreate_sid)
6715 ksec->sid = tsec->keycreate_sid;
6716 else
6717 ksec->sid = tsec->sid;
6718
6719 k->security = ksec;
6720 return 0;
6721}
6722
6723static void selinux_key_free(struct key *k)
6724{
6725 struct key_security_struct *ksec = k->security;
6726
6727 k->security = NULL;
6728 kfree(ksec);
6729}
6730
6731static int selinux_key_permission(key_ref_t key_ref,
6732 const struct cred *cred,
6733 enum key_need_perm need_perm)
6734{
6735 struct key *key;
6736 struct key_security_struct *ksec;
6737 u32 perm, sid;
6738
6739 switch (need_perm) {
6740 case KEY_NEED_VIEW:
6741 perm = KEY__VIEW;
6742 break;
6743 case KEY_NEED_READ:
6744 perm = KEY__READ;
6745 break;
6746 case KEY_NEED_WRITE:
6747 perm = KEY__WRITE;
6748 break;
6749 case KEY_NEED_SEARCH:
6750 perm = KEY__SEARCH;
6751 break;
6752 case KEY_NEED_LINK:
6753 perm = KEY__LINK;
6754 break;
6755 case KEY_NEED_SETATTR:
6756 perm = KEY__SETATTR;
6757 break;
6758 case KEY_NEED_UNLINK:
6759 case KEY_SYSADMIN_OVERRIDE:
6760 case KEY_AUTHTOKEN_OVERRIDE:
6761 case KEY_DEFER_PERM_CHECK:
6762 return 0;
6763 default:
6764 WARN_ON(1);
6765 return -EPERM;
6766
6767 }
6768
6769 sid = cred_sid(cred);
6770 key = key_ref_to_ptr(key_ref);
6771 ksec = key->security;
6772
6773 return avc_has_perm(&selinux_state,
6774 sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6775}
6776
6777static int selinux_key_getsecurity(struct key *key, char **_buffer)
6778{
6779 struct key_security_struct *ksec = key->security;
6780 char *context = NULL;
6781 unsigned len;
6782 int rc;
6783
6784 rc = security_sid_to_context(&selinux_state, ksec->sid,
6785 &context, &len);
6786 if (!rc)
6787 rc = len;
6788 *_buffer = context;
6789 return rc;
6790}
6791
6792#ifdef CONFIG_KEY_NOTIFICATIONS
6793static int selinux_watch_key(struct key *key)
6794{
6795 struct key_security_struct *ksec = key->security;
6796 u32 sid = current_sid();
6797
6798 return avc_has_perm(&selinux_state,
6799 sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6800}
6801#endif
6802#endif
6803
6804#ifdef CONFIG_SECURITY_INFINIBAND
6805static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6806{
6807 struct common_audit_data ad;
6808 int err;
6809 u32 sid = 0;
6810 struct ib_security_struct *sec = ib_sec;
6811 struct lsm_ibpkey_audit ibpkey;
6812
6813 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6814 if (err)
6815 return err;
6816
6817 ad.type = LSM_AUDIT_DATA_IBPKEY;
6818 ibpkey.subnet_prefix = subnet_prefix;
6819 ibpkey.pkey = pkey_val;
6820 ad.u.ibpkey = &ibpkey;
6821 return avc_has_perm(&selinux_state,
6822 sec->sid, sid,
6823 SECCLASS_INFINIBAND_PKEY,
6824 INFINIBAND_PKEY__ACCESS, &ad);
6825}
6826
6827static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6828 u8 port_num)
6829{
6830 struct common_audit_data ad;
6831 int err;
6832 u32 sid = 0;
6833 struct ib_security_struct *sec = ib_sec;
6834 struct lsm_ibendport_audit ibendport;
6835
6836 err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6837 &sid);
6838
6839 if (err)
6840 return err;
6841
6842 ad.type = LSM_AUDIT_DATA_IBENDPORT;
6843 ibendport.dev_name = dev_name;
6844 ibendport.port = port_num;
6845 ad.u.ibendport = &ibendport;
6846 return avc_has_perm(&selinux_state,
6847 sec->sid, sid,
6848 SECCLASS_INFINIBAND_ENDPORT,
6849 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6850}
6851
6852static int selinux_ib_alloc_security(void **ib_sec)
6853{
6854 struct ib_security_struct *sec;
6855
6856 sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6857 if (!sec)
6858 return -ENOMEM;
6859 sec->sid = current_sid();
6860
6861 *ib_sec = sec;
6862 return 0;
6863}
6864
6865static void selinux_ib_free_security(void *ib_sec)
6866{
6867 kfree(ib_sec);
6868}
6869#endif
6870
6871#ifdef CONFIG_BPF_SYSCALL
6872static int selinux_bpf(int cmd, union bpf_attr *attr,
6873 unsigned int size)
6874{
6875 u32 sid = current_sid();
6876 int ret;
6877
6878 switch (cmd) {
6879 case BPF_MAP_CREATE:
6880 ret = avc_has_perm(&selinux_state,
6881 sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6882 NULL);
6883 break;
6884 case BPF_PROG_LOAD:
6885 ret = avc_has_perm(&selinux_state,
6886 sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6887 NULL);
6888 break;
6889 default:
6890 ret = 0;
6891 break;
6892 }
6893
6894 return ret;
6895}
6896
6897static u32 bpf_map_fmode_to_av(fmode_t fmode)
6898{
6899 u32 av = 0;
6900
6901 if (fmode & FMODE_READ)
6902 av |= BPF__MAP_READ;
6903 if (fmode & FMODE_WRITE)
6904 av |= BPF__MAP_WRITE;
6905 return av;
6906}
6907
6908/* This function will check the file pass through unix socket or binder to see
6909 * if it is a bpf related object. And apply correspinding checks on the bpf
6910 * object based on the type. The bpf maps and programs, not like other files and
6911 * socket, are using a shared anonymous inode inside the kernel as their inode.
6912 * So checking that inode cannot identify if the process have privilege to
6913 * access the bpf object and that's why we have to add this additional check in
6914 * selinux_file_receive and selinux_binder_transfer_files.
6915 */
6916static int bpf_fd_pass(struct file *file, u32 sid)
6917{
6918 struct bpf_security_struct *bpfsec;
6919 struct bpf_prog *prog;
6920 struct bpf_map *map;
6921 int ret;
6922
6923 if (file->f_op == &bpf_map_fops) {
6924 map = file->private_data;
6925 bpfsec = map->security;
6926 ret = avc_has_perm(&selinux_state,
6927 sid, bpfsec->sid, SECCLASS_BPF,
6928 bpf_map_fmode_to_av(file->f_mode), NULL);
6929 if (ret)
6930 return ret;
6931 } else if (file->f_op == &bpf_prog_fops) {
6932 prog = file->private_data;
6933 bpfsec = prog->aux->security;
6934 ret = avc_has_perm(&selinux_state,
6935 sid, bpfsec->sid, SECCLASS_BPF,
6936 BPF__PROG_RUN, NULL);
6937 if (ret)
6938 return ret;
6939 }
6940 return 0;
6941}
6942
6943static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6944{
6945 u32 sid = current_sid();
6946 struct bpf_security_struct *bpfsec;
6947
6948 bpfsec = map->security;
6949 return avc_has_perm(&selinux_state,
6950 sid, bpfsec->sid, SECCLASS_BPF,
6951 bpf_map_fmode_to_av(fmode), NULL);
6952}
6953
6954static int selinux_bpf_prog(struct bpf_prog *prog)
6955{
6956 u32 sid = current_sid();
6957 struct bpf_security_struct *bpfsec;
6958
6959 bpfsec = prog->aux->security;
6960 return avc_has_perm(&selinux_state,
6961 sid, bpfsec->sid, SECCLASS_BPF,
6962 BPF__PROG_RUN, NULL);
6963}
6964
6965static int selinux_bpf_map_alloc(struct bpf_map *map)
6966{
6967 struct bpf_security_struct *bpfsec;
6968
6969 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6970 if (!bpfsec)
6971 return -ENOMEM;
6972
6973 bpfsec->sid = current_sid();
6974 map->security = bpfsec;
6975
6976 return 0;
6977}
6978
6979static void selinux_bpf_map_free(struct bpf_map *map)
6980{
6981 struct bpf_security_struct *bpfsec = map->security;
6982
6983 map->security = NULL;
6984 kfree(bpfsec);
6985}
6986
6987static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6988{
6989 struct bpf_security_struct *bpfsec;
6990
6991 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6992 if (!bpfsec)
6993 return -ENOMEM;
6994
6995 bpfsec->sid = current_sid();
6996 aux->security = bpfsec;
6997
6998 return 0;
6999}
7000
7001static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
7002{
7003 struct bpf_security_struct *bpfsec = aux->security;
7004
7005 aux->security = NULL;
7006 kfree(bpfsec);
7007}
7008#endif
7009
7010static int selinux_lockdown(enum lockdown_reason what)
7011{
7012 struct common_audit_data ad;
7013 u32 sid = current_sid();
7014 int invalid_reason = (what <= LOCKDOWN_NONE) ||
7015 (what == LOCKDOWN_INTEGRITY_MAX) ||
7016 (what >= LOCKDOWN_CONFIDENTIALITY_MAX);
7017
7018 if (WARN(invalid_reason, "Invalid lockdown reason")) {
7019 audit_log(audit_context(),
7020 GFP_ATOMIC, AUDIT_SELINUX_ERR,
7021 "lockdown_reason=invalid");
7022 return -EINVAL;
7023 }
7024
7025 ad.type = LSM_AUDIT_DATA_LOCKDOWN;
7026 ad.u.reason = what;
7027
7028 if (what <= LOCKDOWN_INTEGRITY_MAX)
7029 return avc_has_perm(&selinux_state,
7030 sid, sid, SECCLASS_LOCKDOWN,
7031 LOCKDOWN__INTEGRITY, &ad);
7032 else
7033 return avc_has_perm(&selinux_state,
7034 sid, sid, SECCLASS_LOCKDOWN,
7035 LOCKDOWN__CONFIDENTIALITY, &ad);
7036}
7037
7038struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
7039 .lbs_cred = sizeof(struct task_security_struct),
7040 .lbs_file = sizeof(struct file_security_struct),
7041 .lbs_inode = sizeof(struct inode_security_struct),
7042 .lbs_ipc = sizeof(struct ipc_security_struct),
7043 .lbs_msg_msg = sizeof(struct msg_security_struct),
7044 .lbs_superblock = sizeof(struct superblock_security_struct),
7045};
7046
7047#ifdef CONFIG_PERF_EVENTS
7048static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
7049{
7050 u32 requested, sid = current_sid();
7051
7052 if (type == PERF_SECURITY_OPEN)
7053 requested = PERF_EVENT__OPEN;
7054 else if (type == PERF_SECURITY_CPU)
7055 requested = PERF_EVENT__CPU;
7056 else if (type == PERF_SECURITY_KERNEL)
7057 requested = PERF_EVENT__KERNEL;
7058 else if (type == PERF_SECURITY_TRACEPOINT)
7059 requested = PERF_EVENT__TRACEPOINT;
7060 else
7061 return -EINVAL;
7062
7063 return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT,
7064 requested, NULL);
7065}
7066
7067static int selinux_perf_event_alloc(struct perf_event *event)
7068{
7069 struct perf_event_security_struct *perfsec;
7070
7071 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
7072 if (!perfsec)
7073 return -ENOMEM;
7074
7075 perfsec->sid = current_sid();
7076 event->security = perfsec;
7077
7078 return 0;
7079}
7080
7081static void selinux_perf_event_free(struct perf_event *event)
7082{
7083 struct perf_event_security_struct *perfsec = event->security;
7084
7085 event->security = NULL;
7086 kfree(perfsec);
7087}
7088
7089static int selinux_perf_event_read(struct perf_event *event)
7090{
7091 struct perf_event_security_struct *perfsec = event->security;
7092 u32 sid = current_sid();
7093
7094 return avc_has_perm(&selinux_state, sid, perfsec->sid,
7095 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7096}
7097
7098static int selinux_perf_event_write(struct perf_event *event)
7099{
7100 struct perf_event_security_struct *perfsec = event->security;
7101 u32 sid = current_sid();
7102
7103 return avc_has_perm(&selinux_state, sid, perfsec->sid,
7104 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7105}
7106#endif
7107
7108/*
7109 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7110 * 1. any hooks that don't belong to (2.) or (3.) below,
7111 * 2. hooks that both access structures allocated by other hooks, and allocate
7112 * structures that can be later accessed by other hooks (mostly "cloning"
7113 * hooks),
7114 * 3. hooks that only allocate structures that can be later accessed by other
7115 * hooks ("allocating" hooks).
7116 *
7117 * Please follow block comment delimiters in the list to keep this order.
7118 *
7119 * This ordering is needed for SELinux runtime disable to work at least somewhat
7120 * safely. Breaking the ordering rules above might lead to NULL pointer derefs
7121 * when disabling SELinux at runtime.
7122 */
7123static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
7124 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7125 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7126 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7127 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7128
7129 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7130 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7131 LSM_HOOK_INIT(capget, selinux_capget),
7132 LSM_HOOK_INIT(capset, selinux_capset),
7133 LSM_HOOK_INIT(capable, selinux_capable),
7134 LSM_HOOK_INIT(quotactl, selinux_quotactl),
7135 LSM_HOOK_INIT(quota_on, selinux_quota_on),
7136 LSM_HOOK_INIT(syslog, selinux_syslog),
7137 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7138
7139 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7140
7141 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7142 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7143 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7144
7145 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7146 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7147 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7148 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7149 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7150 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7151 LSM_HOOK_INIT(sb_mount, selinux_mount),
7152 LSM_HOOK_INIT(sb_umount, selinux_umount),
7153 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7154 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7155
7156 LSM_HOOK_INIT(move_mount, selinux_move_mount),
7157
7158 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7159 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7160
7161 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7162 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7163 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7164 LSM_HOOK_INIT(inode_create, selinux_inode_create),
7165 LSM_HOOK_INIT(inode_link, selinux_inode_link),
7166 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7167 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7168 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7169 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7170 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7171 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7172 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7173 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7174 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7175 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7176 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7177 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7178 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7179 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7180 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7181 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7182 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7183 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7184 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7185 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7186 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7187 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7188 LSM_HOOK_INIT(path_notify, selinux_path_notify),
7189
7190 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7191
7192 LSM_HOOK_INIT(file_permission, selinux_file_permission),
7193 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7194 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7195 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7196 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7197 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7198 LSM_HOOK_INIT(file_lock, selinux_file_lock),
7199 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7200 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7201 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7202 LSM_HOOK_INIT(file_receive, selinux_file_receive),
7203
7204 LSM_HOOK_INIT(file_open, selinux_file_open),
7205
7206 LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7207 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7208 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7209 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7210 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7211 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7212 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7213 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7214 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7215 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7216 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7217 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7218 LSM_HOOK_INIT(task_getsecid_subj, selinux_task_getsecid_subj),
7219 LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj),
7220 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7221 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7222 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7223 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7224 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7225 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7226 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7227 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7228 LSM_HOOK_INIT(task_kill, selinux_task_kill),
7229 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7230
7231 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7232 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7233
7234 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7235 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7236 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7237 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7238
7239 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7240 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7241 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7242
7243 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7244 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7245 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7246
7247 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7248
7249 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7250 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7251
7252 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7253 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7254 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7255 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7256 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7257 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7258
7259 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7260 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7261
7262 LSM_HOOK_INIT(socket_create, selinux_socket_create),
7263 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7264 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7265 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7266 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7267 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7268 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7269 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7270 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7271 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7272 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7273 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7274 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7275 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7276 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7277 LSM_HOOK_INIT(socket_getpeersec_stream,
7278 selinux_socket_getpeersec_stream),
7279 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7280 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7281 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7282 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7283 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7284 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7285 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7286 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7287 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7288 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7289 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7290 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7291 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7292 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7293 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7294 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7295 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7296 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7297 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7298 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7299#ifdef CONFIG_SECURITY_INFINIBAND
7300 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7301 LSM_HOOK_INIT(ib_endport_manage_subnet,
7302 selinux_ib_endport_manage_subnet),
7303 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7304#endif
7305#ifdef CONFIG_SECURITY_NETWORK_XFRM
7306 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7307 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7308 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7309 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7310 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7311 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7312 selinux_xfrm_state_pol_flow_match),
7313 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7314#endif
7315
7316#ifdef CONFIG_KEYS
7317 LSM_HOOK_INIT(key_free, selinux_key_free),
7318 LSM_HOOK_INIT(key_permission, selinux_key_permission),
7319 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7320#ifdef CONFIG_KEY_NOTIFICATIONS
7321 LSM_HOOK_INIT(watch_key, selinux_watch_key),
7322#endif
7323#endif
7324
7325#ifdef CONFIG_AUDIT
7326 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7327 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7328 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7329#endif
7330
7331#ifdef CONFIG_BPF_SYSCALL
7332 LSM_HOOK_INIT(bpf, selinux_bpf),
7333 LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7334 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7335 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7336 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7337#endif
7338
7339#ifdef CONFIG_PERF_EVENTS
7340 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7341 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7342 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7343 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7344#endif
7345
7346 LSM_HOOK_INIT(locked_down, selinux_lockdown),
7347
7348 /*
7349 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7350 */
7351 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7352 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7353 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7354 LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt),
7355#ifdef CONFIG_SECURITY_NETWORK_XFRM
7356 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7357#endif
7358
7359 /*
7360 * PUT "ALLOCATING" HOOKS HERE
7361 */
7362 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7363 LSM_HOOK_INIT(msg_queue_alloc_security,
7364 selinux_msg_queue_alloc_security),
7365 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7366 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7367 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7368 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7369 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7370 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7371 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7372 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7373#ifdef CONFIG_SECURITY_INFINIBAND
7374 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7375#endif
7376#ifdef CONFIG_SECURITY_NETWORK_XFRM
7377 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7378 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7379 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7380 selinux_xfrm_state_alloc_acquire),
7381#endif
7382#ifdef CONFIG_KEYS
7383 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7384#endif
7385#ifdef CONFIG_AUDIT
7386 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7387#endif
7388#ifdef CONFIG_BPF_SYSCALL
7389 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7390 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7391#endif
7392#ifdef CONFIG_PERF_EVENTS
7393 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7394#endif
7395};
7396
7397static __init int selinux_init(void)
7398{
7399 pr_info("SELinux: Initializing.\n");
7400
7401 memset(&selinux_state, 0, sizeof(selinux_state));
7402 enforcing_set(&selinux_state, selinux_enforcing_boot);
7403 checkreqprot_set(&selinux_state, selinux_checkreqprot_boot);
7404 selinux_avc_init(&selinux_state.avc);
7405 mutex_init(&selinux_state.status_lock);
7406 mutex_init(&selinux_state.policy_mutex);
7407
7408 /* Set the security state for the initial task. */
7409 cred_init_security();
7410
7411 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7412
7413 avc_init();
7414
7415 avtab_cache_init();
7416
7417 ebitmap_cache_init();
7418
7419 hashtab_cache_init();
7420
7421 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7422
7423 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7424 panic("SELinux: Unable to register AVC netcache callback\n");
7425
7426 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7427 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7428
7429 if (selinux_enforcing_boot)
7430 pr_debug("SELinux: Starting in enforcing mode\n");
7431 else
7432 pr_debug("SELinux: Starting in permissive mode\n");
7433
7434 fs_validate_description("selinux", selinux_fs_parameters);
7435
7436 return 0;
7437}
7438
7439static void delayed_superblock_init(struct super_block *sb, void *unused)
7440{
7441 selinux_set_mnt_opts(sb, NULL, 0, NULL);
7442}
7443
7444void selinux_complete_init(void)
7445{
7446 pr_debug("SELinux: Completing initialization.\n");
7447
7448 /* Set up any superblocks initialized prior to the policy load. */
7449 pr_debug("SELinux: Setting up existing superblocks.\n");
7450 iterate_supers(delayed_superblock_init, NULL);
7451}
7452
7453/* SELinux requires early initialization in order to label
7454 all processes and objects when they are created. */
7455DEFINE_LSM(selinux) = {
7456 .name = "selinux",
7457 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7458 .enabled = &selinux_enabled_boot,
7459 .blobs = &selinux_blob_sizes,
7460 .init = selinux_init,
7461};
7462
7463#if defined(CONFIG_NETFILTER)
7464
7465static const struct nf_hook_ops selinux_nf_ops[] = {
7466 {
7467 .hook = selinux_ipv4_postroute,
7468 .pf = NFPROTO_IPV4,
7469 .hooknum = NF_INET_POST_ROUTING,
7470 .priority = NF_IP_PRI_SELINUX_LAST,
7471 },
7472 {
7473 .hook = selinux_ipv4_forward,
7474 .pf = NFPROTO_IPV4,
7475 .hooknum = NF_INET_FORWARD,
7476 .priority = NF_IP_PRI_SELINUX_FIRST,
7477 },
7478 {
7479 .hook = selinux_ipv4_output,
7480 .pf = NFPROTO_IPV4,
7481 .hooknum = NF_INET_LOCAL_OUT,
7482 .priority = NF_IP_PRI_SELINUX_FIRST,
7483 },
7484#if IS_ENABLED(CONFIG_IPV6)
7485 {
7486 .hook = selinux_ipv6_postroute,
7487 .pf = NFPROTO_IPV6,
7488 .hooknum = NF_INET_POST_ROUTING,
7489 .priority = NF_IP6_PRI_SELINUX_LAST,
7490 },
7491 {
7492 .hook = selinux_ipv6_forward,
7493 .pf = NFPROTO_IPV6,
7494 .hooknum = NF_INET_FORWARD,
7495 .priority = NF_IP6_PRI_SELINUX_FIRST,
7496 },
7497 {
7498 .hook = selinux_ipv6_output,
7499 .pf = NFPROTO_IPV6,
7500 .hooknum = NF_INET_LOCAL_OUT,
7501 .priority = NF_IP6_PRI_SELINUX_FIRST,
7502 },
7503#endif /* IPV6 */
7504};
7505
7506static int __net_init selinux_nf_register(struct net *net)
7507{
7508 return nf_register_net_hooks(net, selinux_nf_ops,
7509 ARRAY_SIZE(selinux_nf_ops));
7510}
7511
7512static void __net_exit selinux_nf_unregister(struct net *net)
7513{
7514 nf_unregister_net_hooks(net, selinux_nf_ops,
7515 ARRAY_SIZE(selinux_nf_ops));
7516}
7517
7518static struct pernet_operations selinux_net_ops = {
7519 .init = selinux_nf_register,
7520 .exit = selinux_nf_unregister,
7521};
7522
7523static int __init selinux_nf_ip_init(void)
7524{
7525 int err;
7526
7527 if (!selinux_enabled_boot)
7528 return 0;
7529
7530 pr_debug("SELinux: Registering netfilter hooks\n");
7531
7532 err = register_pernet_subsys(&selinux_net_ops);
7533 if (err)
7534 panic("SELinux: register_pernet_subsys: error %d\n", err);
7535
7536 return 0;
7537}
7538__initcall(selinux_nf_ip_init);
7539
7540#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7541static void selinux_nf_ip_exit(void)
7542{
7543 pr_debug("SELinux: Unregistering netfilter hooks\n");
7544
7545 unregister_pernet_subsys(&selinux_net_ops);
7546}
7547#endif
7548
7549#else /* CONFIG_NETFILTER */
7550
7551#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7552#define selinux_nf_ip_exit()
7553#endif
7554
7555#endif /* CONFIG_NETFILTER */
7556
7557#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7558int selinux_disable(struct selinux_state *state)
7559{
7560 if (selinux_initialized(state)) {
7561 /* Not permitted after initial policy load. */
7562 return -EINVAL;
7563 }
7564
7565 if (selinux_disabled(state)) {
7566 /* Only do this once. */
7567 return -EINVAL;
7568 }
7569
7570 selinux_mark_disabled(state);
7571
7572 pr_info("SELinux: Disabled at runtime.\n");
7573
7574 /*
7575 * Unregister netfilter hooks.
7576 * Must be done before security_delete_hooks() to avoid breaking
7577 * runtime disable.
7578 */
7579 selinux_nf_ip_exit();
7580
7581 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7582
7583 /* Try to destroy the avc node cache */
7584 avc_disable();
7585
7586 /* Unregister selinuxfs. */
7587 exit_sel_fs();
7588
7589 return 0;
7590}
7591#endif