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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * NSA Security-Enhanced Linux (SELinux) security module
4 *
5 * This file contains the SELinux hook function implementations.
6 *
7 * Authors: Stephen Smalley, <sds@tycho.nsa.gov>
8 * Chris Vance, <cvance@nai.com>
9 * Wayne Salamon, <wsalamon@nai.com>
10 * James Morris <jmorris@redhat.com>
11 *
12 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
13 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
14 * Eric Paris <eparis@redhat.com>
15 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
16 * <dgoeddel@trustedcs.com>
17 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
18 * Paul Moore <paul@paul-moore.com>
19 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
20 * Yuichi Nakamura <ynakam@hitachisoft.jp>
21 * Copyright (C) 2016 Mellanox Technologies
22 */
23
24#include <linux/init.h>
25#include <linux/kd.h>
26#include <linux/kernel.h>
27#include <linux/tracehook.h>
28#include <linux/errno.h>
29#include <linux/sched/signal.h>
30#include <linux/sched/task.h>
31#include <linux/lsm_hooks.h>
32#include <linux/xattr.h>
33#include <linux/capability.h>
34#include <linux/unistd.h>
35#include <linux/mm.h>
36#include <linux/mman.h>
37#include <linux/slab.h>
38#include <linux/pagemap.h>
39#include <linux/proc_fs.h>
40#include <linux/swap.h>
41#include <linux/spinlock.h>
42#include <linux/syscalls.h>
43#include <linux/dcache.h>
44#include <linux/file.h>
45#include <linux/fdtable.h>
46#include <linux/namei.h>
47#include <linux/mount.h>
48#include <linux/fs_context.h>
49#include <linux/fs_parser.h>
50#include <linux/netfilter_ipv4.h>
51#include <linux/netfilter_ipv6.h>
52#include <linux/tty.h>
53#include <net/icmp.h>
54#include <net/ip.h> /* for local_port_range[] */
55#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
56#include <net/inet_connection_sock.h>
57#include <net/net_namespace.h>
58#include <net/netlabel.h>
59#include <linux/uaccess.h>
60#include <asm/ioctls.h>
61#include <linux/atomic.h>
62#include <linux/bitops.h>
63#include <linux/interrupt.h>
64#include <linux/netdevice.h> /* for network interface checks */
65#include <net/netlink.h>
66#include <linux/tcp.h>
67#include <linux/udp.h>
68#include <linux/dccp.h>
69#include <linux/sctp.h>
70#include <net/sctp/structs.h>
71#include <linux/quota.h>
72#include <linux/un.h> /* for Unix socket types */
73#include <net/af_unix.h> /* for Unix socket types */
74#include <linux/parser.h>
75#include <linux/nfs_mount.h>
76#include <net/ipv6.h>
77#include <linux/hugetlb.h>
78#include <linux/personality.h>
79#include <linux/audit.h>
80#include <linux/string.h>
81#include <linux/mutex.h>
82#include <linux/posix-timers.h>
83#include <linux/syslog.h>
84#include <linux/user_namespace.h>
85#include <linux/export.h>
86#include <linux/msg.h>
87#include <linux/shm.h>
88#include <linux/bpf.h>
89#include <linux/kernfs.h>
90#include <linux/stringhash.h> /* for hashlen_string() */
91#include <uapi/linux/mount.h>
92#include <linux/fsnotify.h>
93#include <linux/fanotify.h>
94
95#include "avc.h"
96#include "objsec.h"
97#include "netif.h"
98#include "netnode.h"
99#include "netport.h"
100#include "ibpkey.h"
101#include "xfrm.h"
102#include "netlabel.h"
103#include "audit.h"
104#include "avc_ss.h"
105
106struct selinux_state selinux_state;
107
108/* SECMARK reference count */
109static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
110
111#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
112static int selinux_enforcing_boot;
113
114static int __init enforcing_setup(char *str)
115{
116 unsigned long enforcing;
117 if (!kstrtoul(str, 0, &enforcing))
118 selinux_enforcing_boot = enforcing ? 1 : 0;
119 return 1;
120}
121__setup("enforcing=", enforcing_setup);
122#else
123#define selinux_enforcing_boot 1
124#endif
125
126int selinux_enabled __lsm_ro_after_init = 1;
127#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
128static int __init selinux_enabled_setup(char *str)
129{
130 unsigned long enabled;
131 if (!kstrtoul(str, 0, &enabled))
132 selinux_enabled = enabled ? 1 : 0;
133 return 1;
134}
135__setup("selinux=", selinux_enabled_setup);
136#endif
137
138static unsigned int selinux_checkreqprot_boot =
139 CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
140
141static int __init checkreqprot_setup(char *str)
142{
143 unsigned long checkreqprot;
144
145 if (!kstrtoul(str, 0, &checkreqprot))
146 selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
147 return 1;
148}
149__setup("checkreqprot=", checkreqprot_setup);
150
151/**
152 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
153 *
154 * Description:
155 * This function checks the SECMARK reference counter to see if any SECMARK
156 * targets are currently configured, if the reference counter is greater than
157 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
158 * enabled, false (0) if SECMARK is disabled. If the always_check_network
159 * policy capability is enabled, SECMARK is always considered enabled.
160 *
161 */
162static int selinux_secmark_enabled(void)
163{
164 return (selinux_policycap_alwaysnetwork() ||
165 atomic_read(&selinux_secmark_refcount));
166}
167
168/**
169 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
170 *
171 * Description:
172 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true
173 * (1) if any are enabled or false (0) if neither are enabled. If the
174 * always_check_network policy capability is enabled, peer labeling
175 * is always considered enabled.
176 *
177 */
178static int selinux_peerlbl_enabled(void)
179{
180 return (selinux_policycap_alwaysnetwork() ||
181 netlbl_enabled() || selinux_xfrm_enabled());
182}
183
184static int selinux_netcache_avc_callback(u32 event)
185{
186 if (event == AVC_CALLBACK_RESET) {
187 sel_netif_flush();
188 sel_netnode_flush();
189 sel_netport_flush();
190 synchronize_net();
191 }
192 return 0;
193}
194
195static int selinux_lsm_notifier_avc_callback(u32 event)
196{
197 if (event == AVC_CALLBACK_RESET) {
198 sel_ib_pkey_flush();
199 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
200 }
201
202 return 0;
203}
204
205/*
206 * initialise the security for the init task
207 */
208static void cred_init_security(void)
209{
210 struct cred *cred = (struct cred *) current->real_cred;
211 struct task_security_struct *tsec;
212
213 tsec = selinux_cred(cred);
214 tsec->osid = tsec->sid = SECINITSID_KERNEL;
215}
216
217/*
218 * get the security ID of a set of credentials
219 */
220static inline u32 cred_sid(const struct cred *cred)
221{
222 const struct task_security_struct *tsec;
223
224 tsec = selinux_cred(cred);
225 return tsec->sid;
226}
227
228/*
229 * get the objective security ID of a task
230 */
231static inline u32 task_sid(const struct task_struct *task)
232{
233 u32 sid;
234
235 rcu_read_lock();
236 sid = cred_sid(__task_cred(task));
237 rcu_read_unlock();
238 return sid;
239}
240
241/* Allocate and free functions for each kind of security blob. */
242
243static int inode_alloc_security(struct inode *inode)
244{
245 struct inode_security_struct *isec = selinux_inode(inode);
246 u32 sid = current_sid();
247
248 spin_lock_init(&isec->lock);
249 INIT_LIST_HEAD(&isec->list);
250 isec->inode = inode;
251 isec->sid = SECINITSID_UNLABELED;
252 isec->sclass = SECCLASS_FILE;
253 isec->task_sid = sid;
254 isec->initialized = LABEL_INVALID;
255
256 return 0;
257}
258
259static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
260
261/*
262 * Try reloading inode security labels that have been marked as invalid. The
263 * @may_sleep parameter indicates when sleeping and thus reloading labels is
264 * allowed; when set to false, returns -ECHILD when the label is
265 * invalid. The @dentry parameter should be set to a dentry of the inode.
266 */
267static int __inode_security_revalidate(struct inode *inode,
268 struct dentry *dentry,
269 bool may_sleep)
270{
271 struct inode_security_struct *isec = selinux_inode(inode);
272
273 might_sleep_if(may_sleep);
274
275 if (selinux_state.initialized &&
276 isec->initialized != LABEL_INITIALIZED) {
277 if (!may_sleep)
278 return -ECHILD;
279
280 /*
281 * Try reloading the inode security label. This will fail if
282 * @opt_dentry is NULL and no dentry for this inode can be
283 * found; in that case, continue using the old label.
284 */
285 inode_doinit_with_dentry(inode, dentry);
286 }
287 return 0;
288}
289
290static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
291{
292 return selinux_inode(inode);
293}
294
295static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
296{
297 int error;
298
299 error = __inode_security_revalidate(inode, NULL, !rcu);
300 if (error)
301 return ERR_PTR(error);
302 return selinux_inode(inode);
303}
304
305/*
306 * Get the security label of an inode.
307 */
308static struct inode_security_struct *inode_security(struct inode *inode)
309{
310 __inode_security_revalidate(inode, NULL, true);
311 return selinux_inode(inode);
312}
313
314static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
315{
316 struct inode *inode = d_backing_inode(dentry);
317
318 return selinux_inode(inode);
319}
320
321/*
322 * Get the security label of a dentry's backing inode.
323 */
324static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
325{
326 struct inode *inode = d_backing_inode(dentry);
327
328 __inode_security_revalidate(inode, dentry, true);
329 return selinux_inode(inode);
330}
331
332static void inode_free_security(struct inode *inode)
333{
334 struct inode_security_struct *isec = selinux_inode(inode);
335 struct superblock_security_struct *sbsec;
336
337 if (!isec)
338 return;
339 sbsec = inode->i_sb->s_security;
340 /*
341 * As not all inode security structures are in a list, we check for
342 * empty list outside of the lock to make sure that we won't waste
343 * time taking a lock doing nothing.
344 *
345 * The list_del_init() function can be safely called more than once.
346 * It should not be possible for this function to be called with
347 * concurrent list_add(), but for better safety against future changes
348 * in the code, we use list_empty_careful() here.
349 */
350 if (!list_empty_careful(&isec->list)) {
351 spin_lock(&sbsec->isec_lock);
352 list_del_init(&isec->list);
353 spin_unlock(&sbsec->isec_lock);
354 }
355}
356
357static int file_alloc_security(struct file *file)
358{
359 struct file_security_struct *fsec = selinux_file(file);
360 u32 sid = current_sid();
361
362 fsec->sid = sid;
363 fsec->fown_sid = sid;
364
365 return 0;
366}
367
368static int superblock_alloc_security(struct super_block *sb)
369{
370 struct superblock_security_struct *sbsec;
371
372 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
373 if (!sbsec)
374 return -ENOMEM;
375
376 mutex_init(&sbsec->lock);
377 INIT_LIST_HEAD(&sbsec->isec_head);
378 spin_lock_init(&sbsec->isec_lock);
379 sbsec->sb = sb;
380 sbsec->sid = SECINITSID_UNLABELED;
381 sbsec->def_sid = SECINITSID_FILE;
382 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
383 sb->s_security = sbsec;
384
385 return 0;
386}
387
388static void superblock_free_security(struct super_block *sb)
389{
390 struct superblock_security_struct *sbsec = sb->s_security;
391 sb->s_security = NULL;
392 kfree(sbsec);
393}
394
395struct selinux_mnt_opts {
396 const char *fscontext, *context, *rootcontext, *defcontext;
397};
398
399static void selinux_free_mnt_opts(void *mnt_opts)
400{
401 struct selinux_mnt_opts *opts = mnt_opts;
402 kfree(opts->fscontext);
403 kfree(opts->context);
404 kfree(opts->rootcontext);
405 kfree(opts->defcontext);
406 kfree(opts);
407}
408
409static inline int inode_doinit(struct inode *inode)
410{
411 return inode_doinit_with_dentry(inode, NULL);
412}
413
414enum {
415 Opt_error = -1,
416 Opt_context = 0,
417 Opt_defcontext = 1,
418 Opt_fscontext = 2,
419 Opt_rootcontext = 3,
420 Opt_seclabel = 4,
421};
422
423#define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
424static struct {
425 const char *name;
426 int len;
427 int opt;
428 bool has_arg;
429} tokens[] = {
430 A(context, true),
431 A(fscontext, true),
432 A(defcontext, true),
433 A(rootcontext, true),
434 A(seclabel, false),
435};
436#undef A
437
438static int match_opt_prefix(char *s, int l, char **arg)
439{
440 int i;
441
442 for (i = 0; i < ARRAY_SIZE(tokens); i++) {
443 size_t len = tokens[i].len;
444 if (len > l || memcmp(s, tokens[i].name, len))
445 continue;
446 if (tokens[i].has_arg) {
447 if (len == l || s[len] != '=')
448 continue;
449 *arg = s + len + 1;
450 } else if (len != l)
451 continue;
452 return tokens[i].opt;
453 }
454 return Opt_error;
455}
456
457#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
458
459static int may_context_mount_sb_relabel(u32 sid,
460 struct superblock_security_struct *sbsec,
461 const struct cred *cred)
462{
463 const struct task_security_struct *tsec = selinux_cred(cred);
464 int rc;
465
466 rc = avc_has_perm(&selinux_state,
467 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
468 FILESYSTEM__RELABELFROM, NULL);
469 if (rc)
470 return rc;
471
472 rc = avc_has_perm(&selinux_state,
473 tsec->sid, sid, SECCLASS_FILESYSTEM,
474 FILESYSTEM__RELABELTO, NULL);
475 return rc;
476}
477
478static int may_context_mount_inode_relabel(u32 sid,
479 struct superblock_security_struct *sbsec,
480 const struct cred *cred)
481{
482 const struct task_security_struct *tsec = selinux_cred(cred);
483 int rc;
484 rc = avc_has_perm(&selinux_state,
485 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
486 FILESYSTEM__RELABELFROM, NULL);
487 if (rc)
488 return rc;
489
490 rc = avc_has_perm(&selinux_state,
491 sid, sbsec->sid, SECCLASS_FILESYSTEM,
492 FILESYSTEM__ASSOCIATE, NULL);
493 return rc;
494}
495
496static int selinux_is_genfs_special_handling(struct super_block *sb)
497{
498 /* Special handling. Genfs but also in-core setxattr handler */
499 return !strcmp(sb->s_type->name, "sysfs") ||
500 !strcmp(sb->s_type->name, "pstore") ||
501 !strcmp(sb->s_type->name, "debugfs") ||
502 !strcmp(sb->s_type->name, "tracefs") ||
503 !strcmp(sb->s_type->name, "rootfs") ||
504 (selinux_policycap_cgroupseclabel() &&
505 (!strcmp(sb->s_type->name, "cgroup") ||
506 !strcmp(sb->s_type->name, "cgroup2")));
507}
508
509static int selinux_is_sblabel_mnt(struct super_block *sb)
510{
511 struct superblock_security_struct *sbsec = sb->s_security;
512
513 /*
514 * IMPORTANT: Double-check logic in this function when adding a new
515 * SECURITY_FS_USE_* definition!
516 */
517 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
518
519 switch (sbsec->behavior) {
520 case SECURITY_FS_USE_XATTR:
521 case SECURITY_FS_USE_TRANS:
522 case SECURITY_FS_USE_TASK:
523 case SECURITY_FS_USE_NATIVE:
524 return 1;
525
526 case SECURITY_FS_USE_GENFS:
527 return selinux_is_genfs_special_handling(sb);
528
529 /* Never allow relabeling on context mounts */
530 case SECURITY_FS_USE_MNTPOINT:
531 case SECURITY_FS_USE_NONE:
532 default:
533 return 0;
534 }
535}
536
537static int sb_finish_set_opts(struct super_block *sb)
538{
539 struct superblock_security_struct *sbsec = sb->s_security;
540 struct dentry *root = sb->s_root;
541 struct inode *root_inode = d_backing_inode(root);
542 int rc = 0;
543
544 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
545 /* Make sure that the xattr handler exists and that no
546 error other than -ENODATA is returned by getxattr on
547 the root directory. -ENODATA is ok, as this may be
548 the first boot of the SELinux kernel before we have
549 assigned xattr values to the filesystem. */
550 if (!(root_inode->i_opflags & IOP_XATTR)) {
551 pr_warn("SELinux: (dev %s, type %s) has no "
552 "xattr support\n", sb->s_id, sb->s_type->name);
553 rc = -EOPNOTSUPP;
554 goto out;
555 }
556
557 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
558 if (rc < 0 && rc != -ENODATA) {
559 if (rc == -EOPNOTSUPP)
560 pr_warn("SELinux: (dev %s, type "
561 "%s) has no security xattr handler\n",
562 sb->s_id, sb->s_type->name);
563 else
564 pr_warn("SELinux: (dev %s, type "
565 "%s) getxattr errno %d\n", sb->s_id,
566 sb->s_type->name, -rc);
567 goto out;
568 }
569 }
570
571 sbsec->flags |= SE_SBINITIALIZED;
572
573 /*
574 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply
575 * leave the flag untouched because sb_clone_mnt_opts might be handing
576 * us a superblock that needs the flag to be cleared.
577 */
578 if (selinux_is_sblabel_mnt(sb))
579 sbsec->flags |= SBLABEL_MNT;
580 else
581 sbsec->flags &= ~SBLABEL_MNT;
582
583 /* Initialize the root inode. */
584 rc = inode_doinit_with_dentry(root_inode, root);
585
586 /* Initialize any other inodes associated with the superblock, e.g.
587 inodes created prior to initial policy load or inodes created
588 during get_sb by a pseudo filesystem that directly
589 populates itself. */
590 spin_lock(&sbsec->isec_lock);
591 while (!list_empty(&sbsec->isec_head)) {
592 struct inode_security_struct *isec =
593 list_first_entry(&sbsec->isec_head,
594 struct inode_security_struct, list);
595 struct inode *inode = isec->inode;
596 list_del_init(&isec->list);
597 spin_unlock(&sbsec->isec_lock);
598 inode = igrab(inode);
599 if (inode) {
600 if (!IS_PRIVATE(inode))
601 inode_doinit(inode);
602 iput(inode);
603 }
604 spin_lock(&sbsec->isec_lock);
605 }
606 spin_unlock(&sbsec->isec_lock);
607out:
608 return rc;
609}
610
611static int bad_option(struct superblock_security_struct *sbsec, char flag,
612 u32 old_sid, u32 new_sid)
613{
614 char mnt_flags = sbsec->flags & SE_MNTMASK;
615
616 /* check if the old mount command had the same options */
617 if (sbsec->flags & SE_SBINITIALIZED)
618 if (!(sbsec->flags & flag) ||
619 (old_sid != new_sid))
620 return 1;
621
622 /* check if we were passed the same options twice,
623 * aka someone passed context=a,context=b
624 */
625 if (!(sbsec->flags & SE_SBINITIALIZED))
626 if (mnt_flags & flag)
627 return 1;
628 return 0;
629}
630
631static int parse_sid(struct super_block *sb, const char *s, u32 *sid)
632{
633 int rc = security_context_str_to_sid(&selinux_state, s,
634 sid, GFP_KERNEL);
635 if (rc)
636 pr_warn("SELinux: security_context_str_to_sid"
637 "(%s) failed for (dev %s, type %s) errno=%d\n",
638 s, sb->s_id, sb->s_type->name, rc);
639 return rc;
640}
641
642/*
643 * Allow filesystems with binary mount data to explicitly set mount point
644 * labeling information.
645 */
646static int selinux_set_mnt_opts(struct super_block *sb,
647 void *mnt_opts,
648 unsigned long kern_flags,
649 unsigned long *set_kern_flags)
650{
651 const struct cred *cred = current_cred();
652 struct superblock_security_struct *sbsec = sb->s_security;
653 struct dentry *root = sbsec->sb->s_root;
654 struct selinux_mnt_opts *opts = mnt_opts;
655 struct inode_security_struct *root_isec;
656 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
657 u32 defcontext_sid = 0;
658 int rc = 0;
659
660 mutex_lock(&sbsec->lock);
661
662 if (!selinux_state.initialized) {
663 if (!opts) {
664 /* Defer initialization until selinux_complete_init,
665 after the initial policy is loaded and the security
666 server is ready to handle calls. */
667 goto out;
668 }
669 rc = -EINVAL;
670 pr_warn("SELinux: Unable to set superblock options "
671 "before the security server is initialized\n");
672 goto out;
673 }
674 if (kern_flags && !set_kern_flags) {
675 /* Specifying internal flags without providing a place to
676 * place the results is not allowed */
677 rc = -EINVAL;
678 goto out;
679 }
680
681 /*
682 * Binary mount data FS will come through this function twice. Once
683 * from an explicit call and once from the generic calls from the vfs.
684 * Since the generic VFS calls will not contain any security mount data
685 * we need to skip the double mount verification.
686 *
687 * This does open a hole in which we will not notice if the first
688 * mount using this sb set explict options and a second mount using
689 * this sb does not set any security options. (The first options
690 * will be used for both mounts)
691 */
692 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
693 && !opts)
694 goto out;
695
696 root_isec = backing_inode_security_novalidate(root);
697
698 /*
699 * parse the mount options, check if they are valid sids.
700 * also check if someone is trying to mount the same sb more
701 * than once with different security options.
702 */
703 if (opts) {
704 if (opts->fscontext) {
705 rc = parse_sid(sb, opts->fscontext, &fscontext_sid);
706 if (rc)
707 goto out;
708 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
709 fscontext_sid))
710 goto out_double_mount;
711 sbsec->flags |= FSCONTEXT_MNT;
712 }
713 if (opts->context) {
714 rc = parse_sid(sb, opts->context, &context_sid);
715 if (rc)
716 goto out;
717 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
718 context_sid))
719 goto out_double_mount;
720 sbsec->flags |= CONTEXT_MNT;
721 }
722 if (opts->rootcontext) {
723 rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid);
724 if (rc)
725 goto out;
726 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
727 rootcontext_sid))
728 goto out_double_mount;
729 sbsec->flags |= ROOTCONTEXT_MNT;
730 }
731 if (opts->defcontext) {
732 rc = parse_sid(sb, opts->defcontext, &defcontext_sid);
733 if (rc)
734 goto out;
735 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
736 defcontext_sid))
737 goto out_double_mount;
738 sbsec->flags |= DEFCONTEXT_MNT;
739 }
740 }
741
742 if (sbsec->flags & SE_SBINITIALIZED) {
743 /* previously mounted with options, but not on this attempt? */
744 if ((sbsec->flags & SE_MNTMASK) && !opts)
745 goto out_double_mount;
746 rc = 0;
747 goto out;
748 }
749
750 if (strcmp(sb->s_type->name, "proc") == 0)
751 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
752
753 if (!strcmp(sb->s_type->name, "debugfs") ||
754 !strcmp(sb->s_type->name, "tracefs") ||
755 !strcmp(sb->s_type->name, "pstore"))
756 sbsec->flags |= SE_SBGENFS;
757
758 if (!strcmp(sb->s_type->name, "sysfs") ||
759 !strcmp(sb->s_type->name, "cgroup") ||
760 !strcmp(sb->s_type->name, "cgroup2"))
761 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
762
763 if (!sbsec->behavior) {
764 /*
765 * Determine the labeling behavior to use for this
766 * filesystem type.
767 */
768 rc = security_fs_use(&selinux_state, sb);
769 if (rc) {
770 pr_warn("%s: security_fs_use(%s) returned %d\n",
771 __func__, sb->s_type->name, rc);
772 goto out;
773 }
774 }
775
776 /*
777 * If this is a user namespace mount and the filesystem type is not
778 * explicitly whitelisted, then no contexts are allowed on the command
779 * line and security labels must be ignored.
780 */
781 if (sb->s_user_ns != &init_user_ns &&
782 strcmp(sb->s_type->name, "tmpfs") &&
783 strcmp(sb->s_type->name, "ramfs") &&
784 strcmp(sb->s_type->name, "devpts")) {
785 if (context_sid || fscontext_sid || rootcontext_sid ||
786 defcontext_sid) {
787 rc = -EACCES;
788 goto out;
789 }
790 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
791 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
792 rc = security_transition_sid(&selinux_state,
793 current_sid(),
794 current_sid(),
795 SECCLASS_FILE, NULL,
796 &sbsec->mntpoint_sid);
797 if (rc)
798 goto out;
799 }
800 goto out_set_opts;
801 }
802
803 /* sets the context of the superblock for the fs being mounted. */
804 if (fscontext_sid) {
805 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
806 if (rc)
807 goto out;
808
809 sbsec->sid = fscontext_sid;
810 }
811
812 /*
813 * Switch to using mount point labeling behavior.
814 * sets the label used on all file below the mountpoint, and will set
815 * the superblock context if not already set.
816 */
817 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
818 sbsec->behavior = SECURITY_FS_USE_NATIVE;
819 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
820 }
821
822 if (context_sid) {
823 if (!fscontext_sid) {
824 rc = may_context_mount_sb_relabel(context_sid, sbsec,
825 cred);
826 if (rc)
827 goto out;
828 sbsec->sid = context_sid;
829 } else {
830 rc = may_context_mount_inode_relabel(context_sid, sbsec,
831 cred);
832 if (rc)
833 goto out;
834 }
835 if (!rootcontext_sid)
836 rootcontext_sid = context_sid;
837
838 sbsec->mntpoint_sid = context_sid;
839 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
840 }
841
842 if (rootcontext_sid) {
843 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
844 cred);
845 if (rc)
846 goto out;
847
848 root_isec->sid = rootcontext_sid;
849 root_isec->initialized = LABEL_INITIALIZED;
850 }
851
852 if (defcontext_sid) {
853 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
854 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
855 rc = -EINVAL;
856 pr_warn("SELinux: defcontext option is "
857 "invalid for this filesystem type\n");
858 goto out;
859 }
860
861 if (defcontext_sid != sbsec->def_sid) {
862 rc = may_context_mount_inode_relabel(defcontext_sid,
863 sbsec, cred);
864 if (rc)
865 goto out;
866 }
867
868 sbsec->def_sid = defcontext_sid;
869 }
870
871out_set_opts:
872 rc = sb_finish_set_opts(sb);
873out:
874 mutex_unlock(&sbsec->lock);
875 return rc;
876out_double_mount:
877 rc = -EINVAL;
878 pr_warn("SELinux: mount invalid. Same superblock, different "
879 "security settings for (dev %s, type %s)\n", sb->s_id,
880 sb->s_type->name);
881 goto out;
882}
883
884static int selinux_cmp_sb_context(const struct super_block *oldsb,
885 const struct super_block *newsb)
886{
887 struct superblock_security_struct *old = oldsb->s_security;
888 struct superblock_security_struct *new = newsb->s_security;
889 char oldflags = old->flags & SE_MNTMASK;
890 char newflags = new->flags & SE_MNTMASK;
891
892 if (oldflags != newflags)
893 goto mismatch;
894 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
895 goto mismatch;
896 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
897 goto mismatch;
898 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
899 goto mismatch;
900 if (oldflags & ROOTCONTEXT_MNT) {
901 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
902 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
903 if (oldroot->sid != newroot->sid)
904 goto mismatch;
905 }
906 return 0;
907mismatch:
908 pr_warn("SELinux: mount invalid. Same superblock, "
909 "different security settings for (dev %s, "
910 "type %s)\n", newsb->s_id, newsb->s_type->name);
911 return -EBUSY;
912}
913
914static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
915 struct super_block *newsb,
916 unsigned long kern_flags,
917 unsigned long *set_kern_flags)
918{
919 int rc = 0;
920 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
921 struct superblock_security_struct *newsbsec = newsb->s_security;
922
923 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
924 int set_context = (oldsbsec->flags & CONTEXT_MNT);
925 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
926
927 /*
928 * if the parent was able to be mounted it clearly had no special lsm
929 * mount options. thus we can safely deal with this superblock later
930 */
931 if (!selinux_state.initialized)
932 return 0;
933
934 /*
935 * Specifying internal flags without providing a place to
936 * place the results is not allowed.
937 */
938 if (kern_flags && !set_kern_flags)
939 return -EINVAL;
940
941 /* how can we clone if the old one wasn't set up?? */
942 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
943
944 /* if fs is reusing a sb, make sure that the contexts match */
945 if (newsbsec->flags & SE_SBINITIALIZED) {
946 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
947 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
948 return selinux_cmp_sb_context(oldsb, newsb);
949 }
950
951 mutex_lock(&newsbsec->lock);
952
953 newsbsec->flags = oldsbsec->flags;
954
955 newsbsec->sid = oldsbsec->sid;
956 newsbsec->def_sid = oldsbsec->def_sid;
957 newsbsec->behavior = oldsbsec->behavior;
958
959 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
960 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
961 rc = security_fs_use(&selinux_state, newsb);
962 if (rc)
963 goto out;
964 }
965
966 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
967 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
968 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
969 }
970
971 if (set_context) {
972 u32 sid = oldsbsec->mntpoint_sid;
973
974 if (!set_fscontext)
975 newsbsec->sid = sid;
976 if (!set_rootcontext) {
977 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
978 newisec->sid = sid;
979 }
980 newsbsec->mntpoint_sid = sid;
981 }
982 if (set_rootcontext) {
983 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
984 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
985
986 newisec->sid = oldisec->sid;
987 }
988
989 sb_finish_set_opts(newsb);
990out:
991 mutex_unlock(&newsbsec->lock);
992 return rc;
993}
994
995static int selinux_add_opt(int token, const char *s, void **mnt_opts)
996{
997 struct selinux_mnt_opts *opts = *mnt_opts;
998
999 if (token == Opt_seclabel) /* eaten and completely ignored */
1000 return 0;
1001
1002 if (!opts) {
1003 opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
1004 if (!opts)
1005 return -ENOMEM;
1006 *mnt_opts = opts;
1007 }
1008 if (!s)
1009 return -ENOMEM;
1010 switch (token) {
1011 case Opt_context:
1012 if (opts->context || opts->defcontext)
1013 goto Einval;
1014 opts->context = s;
1015 break;
1016 case Opt_fscontext:
1017 if (opts->fscontext)
1018 goto Einval;
1019 opts->fscontext = s;
1020 break;
1021 case Opt_rootcontext:
1022 if (opts->rootcontext)
1023 goto Einval;
1024 opts->rootcontext = s;
1025 break;
1026 case Opt_defcontext:
1027 if (opts->context || opts->defcontext)
1028 goto Einval;
1029 opts->defcontext = s;
1030 break;
1031 }
1032 return 0;
1033Einval:
1034 pr_warn(SEL_MOUNT_FAIL_MSG);
1035 return -EINVAL;
1036}
1037
1038static int selinux_add_mnt_opt(const char *option, const char *val, int len,
1039 void **mnt_opts)
1040{
1041 int token = Opt_error;
1042 int rc, i;
1043
1044 for (i = 0; i < ARRAY_SIZE(tokens); i++) {
1045 if (strcmp(option, tokens[i].name) == 0) {
1046 token = tokens[i].opt;
1047 break;
1048 }
1049 }
1050
1051 if (token == Opt_error)
1052 return -EINVAL;
1053
1054 if (token != Opt_seclabel) {
1055 val = kmemdup_nul(val, len, GFP_KERNEL);
1056 if (!val) {
1057 rc = -ENOMEM;
1058 goto free_opt;
1059 }
1060 }
1061 rc = selinux_add_opt(token, val, mnt_opts);
1062 if (unlikely(rc)) {
1063 kfree(val);
1064 goto free_opt;
1065 }
1066 return rc;
1067
1068free_opt:
1069 if (*mnt_opts) {
1070 selinux_free_mnt_opts(*mnt_opts);
1071 *mnt_opts = NULL;
1072 }
1073 return rc;
1074}
1075
1076static int show_sid(struct seq_file *m, u32 sid)
1077{
1078 char *context = NULL;
1079 u32 len;
1080 int rc;
1081
1082 rc = security_sid_to_context(&selinux_state, sid,
1083 &context, &len);
1084 if (!rc) {
1085 bool has_comma = context && strchr(context, ',');
1086
1087 seq_putc(m, '=');
1088 if (has_comma)
1089 seq_putc(m, '\"');
1090 seq_escape(m, context, "\"\n\\");
1091 if (has_comma)
1092 seq_putc(m, '\"');
1093 }
1094 kfree(context);
1095 return rc;
1096}
1097
1098static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1099{
1100 struct superblock_security_struct *sbsec = sb->s_security;
1101 int rc;
1102
1103 if (!(sbsec->flags & SE_SBINITIALIZED))
1104 return 0;
1105
1106 if (!selinux_state.initialized)
1107 return 0;
1108
1109 if (sbsec->flags & FSCONTEXT_MNT) {
1110 seq_putc(m, ',');
1111 seq_puts(m, FSCONTEXT_STR);
1112 rc = show_sid(m, sbsec->sid);
1113 if (rc)
1114 return rc;
1115 }
1116 if (sbsec->flags & CONTEXT_MNT) {
1117 seq_putc(m, ',');
1118 seq_puts(m, CONTEXT_STR);
1119 rc = show_sid(m, sbsec->mntpoint_sid);
1120 if (rc)
1121 return rc;
1122 }
1123 if (sbsec->flags & DEFCONTEXT_MNT) {
1124 seq_putc(m, ',');
1125 seq_puts(m, DEFCONTEXT_STR);
1126 rc = show_sid(m, sbsec->def_sid);
1127 if (rc)
1128 return rc;
1129 }
1130 if (sbsec->flags & ROOTCONTEXT_MNT) {
1131 struct dentry *root = sbsec->sb->s_root;
1132 struct inode_security_struct *isec = backing_inode_security(root);
1133 seq_putc(m, ',');
1134 seq_puts(m, ROOTCONTEXT_STR);
1135 rc = show_sid(m, isec->sid);
1136 if (rc)
1137 return rc;
1138 }
1139 if (sbsec->flags & SBLABEL_MNT) {
1140 seq_putc(m, ',');
1141 seq_puts(m, SECLABEL_STR);
1142 }
1143 return 0;
1144}
1145
1146static inline u16 inode_mode_to_security_class(umode_t mode)
1147{
1148 switch (mode & S_IFMT) {
1149 case S_IFSOCK:
1150 return SECCLASS_SOCK_FILE;
1151 case S_IFLNK:
1152 return SECCLASS_LNK_FILE;
1153 case S_IFREG:
1154 return SECCLASS_FILE;
1155 case S_IFBLK:
1156 return SECCLASS_BLK_FILE;
1157 case S_IFDIR:
1158 return SECCLASS_DIR;
1159 case S_IFCHR:
1160 return SECCLASS_CHR_FILE;
1161 case S_IFIFO:
1162 return SECCLASS_FIFO_FILE;
1163
1164 }
1165
1166 return SECCLASS_FILE;
1167}
1168
1169static inline int default_protocol_stream(int protocol)
1170{
1171 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1172}
1173
1174static inline int default_protocol_dgram(int protocol)
1175{
1176 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1177}
1178
1179static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1180{
1181 int extsockclass = selinux_policycap_extsockclass();
1182
1183 switch (family) {
1184 case PF_UNIX:
1185 switch (type) {
1186 case SOCK_STREAM:
1187 case SOCK_SEQPACKET:
1188 return SECCLASS_UNIX_STREAM_SOCKET;
1189 case SOCK_DGRAM:
1190 case SOCK_RAW:
1191 return SECCLASS_UNIX_DGRAM_SOCKET;
1192 }
1193 break;
1194 case PF_INET:
1195 case PF_INET6:
1196 switch (type) {
1197 case SOCK_STREAM:
1198 case SOCK_SEQPACKET:
1199 if (default_protocol_stream(protocol))
1200 return SECCLASS_TCP_SOCKET;
1201 else if (extsockclass && protocol == IPPROTO_SCTP)
1202 return SECCLASS_SCTP_SOCKET;
1203 else
1204 return SECCLASS_RAWIP_SOCKET;
1205 case SOCK_DGRAM:
1206 if (default_protocol_dgram(protocol))
1207 return SECCLASS_UDP_SOCKET;
1208 else if (extsockclass && (protocol == IPPROTO_ICMP ||
1209 protocol == IPPROTO_ICMPV6))
1210 return SECCLASS_ICMP_SOCKET;
1211 else
1212 return SECCLASS_RAWIP_SOCKET;
1213 case SOCK_DCCP:
1214 return SECCLASS_DCCP_SOCKET;
1215 default:
1216 return SECCLASS_RAWIP_SOCKET;
1217 }
1218 break;
1219 case PF_NETLINK:
1220 switch (protocol) {
1221 case NETLINK_ROUTE:
1222 return SECCLASS_NETLINK_ROUTE_SOCKET;
1223 case NETLINK_SOCK_DIAG:
1224 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1225 case NETLINK_NFLOG:
1226 return SECCLASS_NETLINK_NFLOG_SOCKET;
1227 case NETLINK_XFRM:
1228 return SECCLASS_NETLINK_XFRM_SOCKET;
1229 case NETLINK_SELINUX:
1230 return SECCLASS_NETLINK_SELINUX_SOCKET;
1231 case NETLINK_ISCSI:
1232 return SECCLASS_NETLINK_ISCSI_SOCKET;
1233 case NETLINK_AUDIT:
1234 return SECCLASS_NETLINK_AUDIT_SOCKET;
1235 case NETLINK_FIB_LOOKUP:
1236 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1237 case NETLINK_CONNECTOR:
1238 return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1239 case NETLINK_NETFILTER:
1240 return SECCLASS_NETLINK_NETFILTER_SOCKET;
1241 case NETLINK_DNRTMSG:
1242 return SECCLASS_NETLINK_DNRT_SOCKET;
1243 case NETLINK_KOBJECT_UEVENT:
1244 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1245 case NETLINK_GENERIC:
1246 return SECCLASS_NETLINK_GENERIC_SOCKET;
1247 case NETLINK_SCSITRANSPORT:
1248 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1249 case NETLINK_RDMA:
1250 return SECCLASS_NETLINK_RDMA_SOCKET;
1251 case NETLINK_CRYPTO:
1252 return SECCLASS_NETLINK_CRYPTO_SOCKET;
1253 default:
1254 return SECCLASS_NETLINK_SOCKET;
1255 }
1256 case PF_PACKET:
1257 return SECCLASS_PACKET_SOCKET;
1258 case PF_KEY:
1259 return SECCLASS_KEY_SOCKET;
1260 case PF_APPLETALK:
1261 return SECCLASS_APPLETALK_SOCKET;
1262 }
1263
1264 if (extsockclass) {
1265 switch (family) {
1266 case PF_AX25:
1267 return SECCLASS_AX25_SOCKET;
1268 case PF_IPX:
1269 return SECCLASS_IPX_SOCKET;
1270 case PF_NETROM:
1271 return SECCLASS_NETROM_SOCKET;
1272 case PF_ATMPVC:
1273 return SECCLASS_ATMPVC_SOCKET;
1274 case PF_X25:
1275 return SECCLASS_X25_SOCKET;
1276 case PF_ROSE:
1277 return SECCLASS_ROSE_SOCKET;
1278 case PF_DECnet:
1279 return SECCLASS_DECNET_SOCKET;
1280 case PF_ATMSVC:
1281 return SECCLASS_ATMSVC_SOCKET;
1282 case PF_RDS:
1283 return SECCLASS_RDS_SOCKET;
1284 case PF_IRDA:
1285 return SECCLASS_IRDA_SOCKET;
1286 case PF_PPPOX:
1287 return SECCLASS_PPPOX_SOCKET;
1288 case PF_LLC:
1289 return SECCLASS_LLC_SOCKET;
1290 case PF_CAN:
1291 return SECCLASS_CAN_SOCKET;
1292 case PF_TIPC:
1293 return SECCLASS_TIPC_SOCKET;
1294 case PF_BLUETOOTH:
1295 return SECCLASS_BLUETOOTH_SOCKET;
1296 case PF_IUCV:
1297 return SECCLASS_IUCV_SOCKET;
1298 case PF_RXRPC:
1299 return SECCLASS_RXRPC_SOCKET;
1300 case PF_ISDN:
1301 return SECCLASS_ISDN_SOCKET;
1302 case PF_PHONET:
1303 return SECCLASS_PHONET_SOCKET;
1304 case PF_IEEE802154:
1305 return SECCLASS_IEEE802154_SOCKET;
1306 case PF_CAIF:
1307 return SECCLASS_CAIF_SOCKET;
1308 case PF_ALG:
1309 return SECCLASS_ALG_SOCKET;
1310 case PF_NFC:
1311 return SECCLASS_NFC_SOCKET;
1312 case PF_VSOCK:
1313 return SECCLASS_VSOCK_SOCKET;
1314 case PF_KCM:
1315 return SECCLASS_KCM_SOCKET;
1316 case PF_QIPCRTR:
1317 return SECCLASS_QIPCRTR_SOCKET;
1318 case PF_SMC:
1319 return SECCLASS_SMC_SOCKET;
1320 case PF_XDP:
1321 return SECCLASS_XDP_SOCKET;
1322#if PF_MAX > 45
1323#error New address family defined, please update this function.
1324#endif
1325 }
1326 }
1327
1328 return SECCLASS_SOCKET;
1329}
1330
1331static int selinux_genfs_get_sid(struct dentry *dentry,
1332 u16 tclass,
1333 u16 flags,
1334 u32 *sid)
1335{
1336 int rc;
1337 struct super_block *sb = dentry->d_sb;
1338 char *buffer, *path;
1339
1340 buffer = (char *)__get_free_page(GFP_KERNEL);
1341 if (!buffer)
1342 return -ENOMEM;
1343
1344 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1345 if (IS_ERR(path))
1346 rc = PTR_ERR(path);
1347 else {
1348 if (flags & SE_SBPROC) {
1349 /* each process gets a /proc/PID/ entry. Strip off the
1350 * PID part to get a valid selinux labeling.
1351 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1352 while (path[1] >= '0' && path[1] <= '9') {
1353 path[1] = '/';
1354 path++;
1355 }
1356 }
1357 rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1358 path, tclass, sid);
1359 if (rc == -ENOENT) {
1360 /* No match in policy, mark as unlabeled. */
1361 *sid = SECINITSID_UNLABELED;
1362 rc = 0;
1363 }
1364 }
1365 free_page((unsigned long)buffer);
1366 return rc;
1367}
1368
1369static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1370 u32 def_sid, u32 *sid)
1371{
1372#define INITCONTEXTLEN 255
1373 char *context;
1374 unsigned int len;
1375 int rc;
1376
1377 len = INITCONTEXTLEN;
1378 context = kmalloc(len + 1, GFP_NOFS);
1379 if (!context)
1380 return -ENOMEM;
1381
1382 context[len] = '\0';
1383 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1384 if (rc == -ERANGE) {
1385 kfree(context);
1386
1387 /* Need a larger buffer. Query for the right size. */
1388 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1389 if (rc < 0)
1390 return rc;
1391
1392 len = rc;
1393 context = kmalloc(len + 1, GFP_NOFS);
1394 if (!context)
1395 return -ENOMEM;
1396
1397 context[len] = '\0';
1398 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1399 context, len);
1400 }
1401 if (rc < 0) {
1402 kfree(context);
1403 if (rc != -ENODATA) {
1404 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n",
1405 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1406 return rc;
1407 }
1408 *sid = def_sid;
1409 return 0;
1410 }
1411
1412 rc = security_context_to_sid_default(&selinux_state, context, rc, sid,
1413 def_sid, GFP_NOFS);
1414 if (rc) {
1415 char *dev = inode->i_sb->s_id;
1416 unsigned long ino = inode->i_ino;
1417
1418 if (rc == -EINVAL) {
1419 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",
1420 ino, dev, context);
1421 } else {
1422 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1423 __func__, context, -rc, dev, ino);
1424 }
1425 }
1426 kfree(context);
1427 return 0;
1428}
1429
1430/* The inode's security attributes must be initialized before first use. */
1431static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1432{
1433 struct superblock_security_struct *sbsec = NULL;
1434 struct inode_security_struct *isec = selinux_inode(inode);
1435 u32 task_sid, sid = 0;
1436 u16 sclass;
1437 struct dentry *dentry;
1438 int rc = 0;
1439
1440 if (isec->initialized == LABEL_INITIALIZED)
1441 return 0;
1442
1443 spin_lock(&isec->lock);
1444 if (isec->initialized == LABEL_INITIALIZED)
1445 goto out_unlock;
1446
1447 if (isec->sclass == SECCLASS_FILE)
1448 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1449
1450 sbsec = inode->i_sb->s_security;
1451 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1452 /* Defer initialization until selinux_complete_init,
1453 after the initial policy is loaded and the security
1454 server is ready to handle calls. */
1455 spin_lock(&sbsec->isec_lock);
1456 if (list_empty(&isec->list))
1457 list_add(&isec->list, &sbsec->isec_head);
1458 spin_unlock(&sbsec->isec_lock);
1459 goto out_unlock;
1460 }
1461
1462 sclass = isec->sclass;
1463 task_sid = isec->task_sid;
1464 sid = isec->sid;
1465 isec->initialized = LABEL_PENDING;
1466 spin_unlock(&isec->lock);
1467
1468 switch (sbsec->behavior) {
1469 case SECURITY_FS_USE_NATIVE:
1470 break;
1471 case SECURITY_FS_USE_XATTR:
1472 if (!(inode->i_opflags & IOP_XATTR)) {
1473 sid = sbsec->def_sid;
1474 break;
1475 }
1476 /* Need a dentry, since the xattr API requires one.
1477 Life would be simpler if we could just pass the inode. */
1478 if (opt_dentry) {
1479 /* Called from d_instantiate or d_splice_alias. */
1480 dentry = dget(opt_dentry);
1481 } else {
1482 /*
1483 * Called from selinux_complete_init, try to find a dentry.
1484 * Some filesystems really want a connected one, so try
1485 * that first. We could split SECURITY_FS_USE_XATTR in
1486 * two, depending upon that...
1487 */
1488 dentry = d_find_alias(inode);
1489 if (!dentry)
1490 dentry = d_find_any_alias(inode);
1491 }
1492 if (!dentry) {
1493 /*
1494 * this is can be hit on boot when a file is accessed
1495 * before the policy is loaded. When we load policy we
1496 * may find inodes that have no dentry on the
1497 * sbsec->isec_head list. No reason to complain as these
1498 * will get fixed up the next time we go through
1499 * inode_doinit with a dentry, before these inodes could
1500 * be used again by userspace.
1501 */
1502 goto out;
1503 }
1504
1505 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1506 &sid);
1507 dput(dentry);
1508 if (rc)
1509 goto out;
1510 break;
1511 case SECURITY_FS_USE_TASK:
1512 sid = task_sid;
1513 break;
1514 case SECURITY_FS_USE_TRANS:
1515 /* Default to the fs SID. */
1516 sid = sbsec->sid;
1517
1518 /* Try to obtain a transition SID. */
1519 rc = security_transition_sid(&selinux_state, task_sid, sid,
1520 sclass, NULL, &sid);
1521 if (rc)
1522 goto out;
1523 break;
1524 case SECURITY_FS_USE_MNTPOINT:
1525 sid = sbsec->mntpoint_sid;
1526 break;
1527 default:
1528 /* Default to the fs superblock SID. */
1529 sid = sbsec->sid;
1530
1531 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1532 /* We must have a dentry to determine the label on
1533 * procfs inodes */
1534 if (opt_dentry) {
1535 /* Called from d_instantiate or
1536 * d_splice_alias. */
1537 dentry = dget(opt_dentry);
1538 } else {
1539 /* Called from selinux_complete_init, try to
1540 * find a dentry. Some filesystems really want
1541 * a connected one, so try that first.
1542 */
1543 dentry = d_find_alias(inode);
1544 if (!dentry)
1545 dentry = d_find_any_alias(inode);
1546 }
1547 /*
1548 * This can be hit on boot when a file is accessed
1549 * before the policy is loaded. When we load policy we
1550 * may find inodes that have no dentry on the
1551 * sbsec->isec_head list. No reason to complain as
1552 * these will get fixed up the next time we go through
1553 * inode_doinit() with a dentry, before these inodes
1554 * could be used again by userspace.
1555 */
1556 if (!dentry)
1557 goto out;
1558 rc = selinux_genfs_get_sid(dentry, sclass,
1559 sbsec->flags, &sid);
1560 if (rc) {
1561 dput(dentry);
1562 goto out;
1563 }
1564
1565 if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1566 (inode->i_opflags & IOP_XATTR)) {
1567 rc = inode_doinit_use_xattr(inode, dentry,
1568 sid, &sid);
1569 if (rc) {
1570 dput(dentry);
1571 goto out;
1572 }
1573 }
1574 dput(dentry);
1575 }
1576 break;
1577 }
1578
1579out:
1580 spin_lock(&isec->lock);
1581 if (isec->initialized == LABEL_PENDING) {
1582 if (!sid || rc) {
1583 isec->initialized = LABEL_INVALID;
1584 goto out_unlock;
1585 }
1586
1587 isec->initialized = LABEL_INITIALIZED;
1588 isec->sid = sid;
1589 }
1590
1591out_unlock:
1592 spin_unlock(&isec->lock);
1593 return rc;
1594}
1595
1596/* Convert a Linux signal to an access vector. */
1597static inline u32 signal_to_av(int sig)
1598{
1599 u32 perm = 0;
1600
1601 switch (sig) {
1602 case SIGCHLD:
1603 /* Commonly granted from child to parent. */
1604 perm = PROCESS__SIGCHLD;
1605 break;
1606 case SIGKILL:
1607 /* Cannot be caught or ignored */
1608 perm = PROCESS__SIGKILL;
1609 break;
1610 case SIGSTOP:
1611 /* Cannot be caught or ignored */
1612 perm = PROCESS__SIGSTOP;
1613 break;
1614 default:
1615 /* All other signals. */
1616 perm = PROCESS__SIGNAL;
1617 break;
1618 }
1619
1620 return perm;
1621}
1622
1623#if CAP_LAST_CAP > 63
1624#error Fix SELinux to handle capabilities > 63.
1625#endif
1626
1627/* Check whether a task is allowed to use a capability. */
1628static int cred_has_capability(const struct cred *cred,
1629 int cap, unsigned int opts, bool initns)
1630{
1631 struct common_audit_data ad;
1632 struct av_decision avd;
1633 u16 sclass;
1634 u32 sid = cred_sid(cred);
1635 u32 av = CAP_TO_MASK(cap);
1636 int rc;
1637
1638 ad.type = LSM_AUDIT_DATA_CAP;
1639 ad.u.cap = cap;
1640
1641 switch (CAP_TO_INDEX(cap)) {
1642 case 0:
1643 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1644 break;
1645 case 1:
1646 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1647 break;
1648 default:
1649 pr_err("SELinux: out of range capability %d\n", cap);
1650 BUG();
1651 return -EINVAL;
1652 }
1653
1654 rc = avc_has_perm_noaudit(&selinux_state,
1655 sid, sid, sclass, av, 0, &avd);
1656 if (!(opts & CAP_OPT_NOAUDIT)) {
1657 int rc2 = avc_audit(&selinux_state,
1658 sid, sid, sclass, av, &avd, rc, &ad, 0);
1659 if (rc2)
1660 return rc2;
1661 }
1662 return rc;
1663}
1664
1665/* Check whether a task has a particular permission to an inode.
1666 The 'adp' parameter is optional and allows other audit
1667 data to be passed (e.g. the dentry). */
1668static int inode_has_perm(const struct cred *cred,
1669 struct inode *inode,
1670 u32 perms,
1671 struct common_audit_data *adp)
1672{
1673 struct inode_security_struct *isec;
1674 u32 sid;
1675
1676 validate_creds(cred);
1677
1678 if (unlikely(IS_PRIVATE(inode)))
1679 return 0;
1680
1681 sid = cred_sid(cred);
1682 isec = selinux_inode(inode);
1683
1684 return avc_has_perm(&selinux_state,
1685 sid, isec->sid, isec->sclass, perms, adp);
1686}
1687
1688/* Same as inode_has_perm, but pass explicit audit data containing
1689 the dentry to help the auditing code to more easily generate the
1690 pathname if needed. */
1691static inline int dentry_has_perm(const struct cred *cred,
1692 struct dentry *dentry,
1693 u32 av)
1694{
1695 struct inode *inode = d_backing_inode(dentry);
1696 struct common_audit_data ad;
1697
1698 ad.type = LSM_AUDIT_DATA_DENTRY;
1699 ad.u.dentry = dentry;
1700 __inode_security_revalidate(inode, dentry, true);
1701 return inode_has_perm(cred, inode, av, &ad);
1702}
1703
1704/* Same as inode_has_perm, but pass explicit audit data containing
1705 the path to help the auditing code to more easily generate the
1706 pathname if needed. */
1707static inline int path_has_perm(const struct cred *cred,
1708 const struct path *path,
1709 u32 av)
1710{
1711 struct inode *inode = d_backing_inode(path->dentry);
1712 struct common_audit_data ad;
1713
1714 ad.type = LSM_AUDIT_DATA_PATH;
1715 ad.u.path = *path;
1716 __inode_security_revalidate(inode, path->dentry, true);
1717 return inode_has_perm(cred, inode, av, &ad);
1718}
1719
1720/* Same as path_has_perm, but uses the inode from the file struct. */
1721static inline int file_path_has_perm(const struct cred *cred,
1722 struct file *file,
1723 u32 av)
1724{
1725 struct common_audit_data ad;
1726
1727 ad.type = LSM_AUDIT_DATA_FILE;
1728 ad.u.file = file;
1729 return inode_has_perm(cred, file_inode(file), av, &ad);
1730}
1731
1732#ifdef CONFIG_BPF_SYSCALL
1733static int bpf_fd_pass(struct file *file, u32 sid);
1734#endif
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 = selinux_file(file);
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_FILE;
1755 ad.u.file = file;
1756
1757 if (sid != fsec->sid) {
1758 rc = avc_has_perm(&selinux_state,
1759 sid, fsec->sid,
1760 SECCLASS_FD,
1761 FD__USE,
1762 &ad);
1763 if (rc)
1764 goto out;
1765 }
1766
1767#ifdef CONFIG_BPF_SYSCALL
1768 rc = bpf_fd_pass(file, cred_sid(cred));
1769 if (rc)
1770 return rc;
1771#endif
1772
1773 /* av is zero if only checking access to the descriptor. */
1774 rc = 0;
1775 if (av)
1776 rc = inode_has_perm(cred, inode, av, &ad);
1777
1778out:
1779 return rc;
1780}
1781
1782/*
1783 * Determine the label for an inode that might be unioned.
1784 */
1785static int
1786selinux_determine_inode_label(const struct task_security_struct *tsec,
1787 struct inode *dir,
1788 const struct qstr *name, u16 tclass,
1789 u32 *_new_isid)
1790{
1791 const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1792
1793 if ((sbsec->flags & SE_SBINITIALIZED) &&
1794 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1795 *_new_isid = sbsec->mntpoint_sid;
1796 } else if ((sbsec->flags & SBLABEL_MNT) &&
1797 tsec->create_sid) {
1798 *_new_isid = tsec->create_sid;
1799 } else {
1800 const struct inode_security_struct *dsec = inode_security(dir);
1801 return security_transition_sid(&selinux_state, tsec->sid,
1802 dsec->sid, tclass,
1803 name, _new_isid);
1804 }
1805
1806 return 0;
1807}
1808
1809/* Check whether a task can create a file. */
1810static int may_create(struct inode *dir,
1811 struct dentry *dentry,
1812 u16 tclass)
1813{
1814 const struct task_security_struct *tsec = selinux_cred(current_cred());
1815 struct inode_security_struct *dsec;
1816 struct superblock_security_struct *sbsec;
1817 u32 sid, newsid;
1818 struct common_audit_data ad;
1819 int rc;
1820
1821 dsec = inode_security(dir);
1822 sbsec = dir->i_sb->s_security;
1823
1824 sid = tsec->sid;
1825
1826 ad.type = LSM_AUDIT_DATA_DENTRY;
1827 ad.u.dentry = dentry;
1828
1829 rc = avc_has_perm(&selinux_state,
1830 sid, dsec->sid, SECCLASS_DIR,
1831 DIR__ADD_NAME | DIR__SEARCH,
1832 &ad);
1833 if (rc)
1834 return rc;
1835
1836 rc = selinux_determine_inode_label(selinux_cred(current_cred()), dir,
1837 &dentry->d_name, tclass, &newsid);
1838 if (rc)
1839 return rc;
1840
1841 rc = avc_has_perm(&selinux_state,
1842 sid, newsid, tclass, FILE__CREATE, &ad);
1843 if (rc)
1844 return rc;
1845
1846 return avc_has_perm(&selinux_state,
1847 newsid, sbsec->sid,
1848 SECCLASS_FILESYSTEM,
1849 FILESYSTEM__ASSOCIATE, &ad);
1850}
1851
1852#define MAY_LINK 0
1853#define MAY_UNLINK 1
1854#define MAY_RMDIR 2
1855
1856/* Check whether a task can link, unlink, or rmdir a file/directory. */
1857static int may_link(struct inode *dir,
1858 struct dentry *dentry,
1859 int kind)
1860
1861{
1862 struct inode_security_struct *dsec, *isec;
1863 struct common_audit_data ad;
1864 u32 sid = current_sid();
1865 u32 av;
1866 int rc;
1867
1868 dsec = inode_security(dir);
1869 isec = backing_inode_security(dentry);
1870
1871 ad.type = LSM_AUDIT_DATA_DENTRY;
1872 ad.u.dentry = dentry;
1873
1874 av = DIR__SEARCH;
1875 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1876 rc = avc_has_perm(&selinux_state,
1877 sid, dsec->sid, SECCLASS_DIR, av, &ad);
1878 if (rc)
1879 return rc;
1880
1881 switch (kind) {
1882 case MAY_LINK:
1883 av = FILE__LINK;
1884 break;
1885 case MAY_UNLINK:
1886 av = FILE__UNLINK;
1887 break;
1888 case MAY_RMDIR:
1889 av = DIR__RMDIR;
1890 break;
1891 default:
1892 pr_warn("SELinux: %s: unrecognized kind %d\n",
1893 __func__, kind);
1894 return 0;
1895 }
1896
1897 rc = avc_has_perm(&selinux_state,
1898 sid, isec->sid, isec->sclass, av, &ad);
1899 return rc;
1900}
1901
1902static inline int may_rename(struct inode *old_dir,
1903 struct dentry *old_dentry,
1904 struct inode *new_dir,
1905 struct dentry *new_dentry)
1906{
1907 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1908 struct common_audit_data ad;
1909 u32 sid = current_sid();
1910 u32 av;
1911 int old_is_dir, new_is_dir;
1912 int rc;
1913
1914 old_dsec = inode_security(old_dir);
1915 old_isec = backing_inode_security(old_dentry);
1916 old_is_dir = d_is_dir(old_dentry);
1917 new_dsec = inode_security(new_dir);
1918
1919 ad.type = LSM_AUDIT_DATA_DENTRY;
1920
1921 ad.u.dentry = old_dentry;
1922 rc = avc_has_perm(&selinux_state,
1923 sid, old_dsec->sid, SECCLASS_DIR,
1924 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1925 if (rc)
1926 return rc;
1927 rc = avc_has_perm(&selinux_state,
1928 sid, old_isec->sid,
1929 old_isec->sclass, FILE__RENAME, &ad);
1930 if (rc)
1931 return rc;
1932 if (old_is_dir && new_dir != old_dir) {
1933 rc = avc_has_perm(&selinux_state,
1934 sid, old_isec->sid,
1935 old_isec->sclass, DIR__REPARENT, &ad);
1936 if (rc)
1937 return rc;
1938 }
1939
1940 ad.u.dentry = new_dentry;
1941 av = DIR__ADD_NAME | DIR__SEARCH;
1942 if (d_is_positive(new_dentry))
1943 av |= DIR__REMOVE_NAME;
1944 rc = avc_has_perm(&selinux_state,
1945 sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1946 if (rc)
1947 return rc;
1948 if (d_is_positive(new_dentry)) {
1949 new_isec = backing_inode_security(new_dentry);
1950 new_is_dir = d_is_dir(new_dentry);
1951 rc = avc_has_perm(&selinux_state,
1952 sid, new_isec->sid,
1953 new_isec->sclass,
1954 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1955 if (rc)
1956 return rc;
1957 }
1958
1959 return 0;
1960}
1961
1962/* Check whether a task can perform a filesystem operation. */
1963static int superblock_has_perm(const struct cred *cred,
1964 struct super_block *sb,
1965 u32 perms,
1966 struct common_audit_data *ad)
1967{
1968 struct superblock_security_struct *sbsec;
1969 u32 sid = cred_sid(cred);
1970
1971 sbsec = sb->s_security;
1972 return avc_has_perm(&selinux_state,
1973 sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1974}
1975
1976/* Convert a Linux mode and permission mask to an access vector. */
1977static inline u32 file_mask_to_av(int mode, int mask)
1978{
1979 u32 av = 0;
1980
1981 if (!S_ISDIR(mode)) {
1982 if (mask & MAY_EXEC)
1983 av |= FILE__EXECUTE;
1984 if (mask & MAY_READ)
1985 av |= FILE__READ;
1986
1987 if (mask & MAY_APPEND)
1988 av |= FILE__APPEND;
1989 else if (mask & MAY_WRITE)
1990 av |= FILE__WRITE;
1991
1992 } else {
1993 if (mask & MAY_EXEC)
1994 av |= DIR__SEARCH;
1995 if (mask & MAY_WRITE)
1996 av |= DIR__WRITE;
1997 if (mask & MAY_READ)
1998 av |= DIR__READ;
1999 }
2000
2001 return av;
2002}
2003
2004/* Convert a Linux file to an access vector. */
2005static inline u32 file_to_av(struct file *file)
2006{
2007 u32 av = 0;
2008
2009 if (file->f_mode & FMODE_READ)
2010 av |= FILE__READ;
2011 if (file->f_mode & FMODE_WRITE) {
2012 if (file->f_flags & O_APPEND)
2013 av |= FILE__APPEND;
2014 else
2015 av |= FILE__WRITE;
2016 }
2017 if (!av) {
2018 /*
2019 * Special file opened with flags 3 for ioctl-only use.
2020 */
2021 av = FILE__IOCTL;
2022 }
2023
2024 return av;
2025}
2026
2027/*
2028 * Convert a file to an access vector and include the correct open
2029 * open permission.
2030 */
2031static inline u32 open_file_to_av(struct file *file)
2032{
2033 u32 av = file_to_av(file);
2034 struct inode *inode = file_inode(file);
2035
2036 if (selinux_policycap_openperm() &&
2037 inode->i_sb->s_magic != SOCKFS_MAGIC)
2038 av |= FILE__OPEN;
2039
2040 return av;
2041}
2042
2043/* Hook functions begin here. */
2044
2045static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2046{
2047 u32 mysid = current_sid();
2048 u32 mgrsid = task_sid(mgr);
2049
2050 return avc_has_perm(&selinux_state,
2051 mysid, mgrsid, SECCLASS_BINDER,
2052 BINDER__SET_CONTEXT_MGR, NULL);
2053}
2054
2055static int selinux_binder_transaction(struct task_struct *from,
2056 struct task_struct *to)
2057{
2058 u32 mysid = current_sid();
2059 u32 fromsid = task_sid(from);
2060 u32 tosid = task_sid(to);
2061 int rc;
2062
2063 if (mysid != fromsid) {
2064 rc = avc_has_perm(&selinux_state,
2065 mysid, fromsid, SECCLASS_BINDER,
2066 BINDER__IMPERSONATE, NULL);
2067 if (rc)
2068 return rc;
2069 }
2070
2071 return avc_has_perm(&selinux_state,
2072 fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2073 NULL);
2074}
2075
2076static int selinux_binder_transfer_binder(struct task_struct *from,
2077 struct task_struct *to)
2078{
2079 u32 fromsid = task_sid(from);
2080 u32 tosid = task_sid(to);
2081
2082 return avc_has_perm(&selinux_state,
2083 fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2084 NULL);
2085}
2086
2087static int selinux_binder_transfer_file(struct task_struct *from,
2088 struct task_struct *to,
2089 struct file *file)
2090{
2091 u32 sid = task_sid(to);
2092 struct file_security_struct *fsec = selinux_file(file);
2093 struct dentry *dentry = file->f_path.dentry;
2094 struct inode_security_struct *isec;
2095 struct common_audit_data ad;
2096 int rc;
2097
2098 ad.type = LSM_AUDIT_DATA_PATH;
2099 ad.u.path = file->f_path;
2100
2101 if (sid != fsec->sid) {
2102 rc = avc_has_perm(&selinux_state,
2103 sid, fsec->sid,
2104 SECCLASS_FD,
2105 FD__USE,
2106 &ad);
2107 if (rc)
2108 return rc;
2109 }
2110
2111#ifdef CONFIG_BPF_SYSCALL
2112 rc = bpf_fd_pass(file, sid);
2113 if (rc)
2114 return rc;
2115#endif
2116
2117 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2118 return 0;
2119
2120 isec = backing_inode_security(dentry);
2121 return avc_has_perm(&selinux_state,
2122 sid, isec->sid, isec->sclass, file_to_av(file),
2123 &ad);
2124}
2125
2126static int selinux_ptrace_access_check(struct task_struct *child,
2127 unsigned int mode)
2128{
2129 u32 sid = current_sid();
2130 u32 csid = task_sid(child);
2131
2132 if (mode & PTRACE_MODE_READ)
2133 return avc_has_perm(&selinux_state,
2134 sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2135
2136 return avc_has_perm(&selinux_state,
2137 sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2138}
2139
2140static int selinux_ptrace_traceme(struct task_struct *parent)
2141{
2142 return avc_has_perm(&selinux_state,
2143 task_sid(parent), current_sid(), SECCLASS_PROCESS,
2144 PROCESS__PTRACE, NULL);
2145}
2146
2147static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2148 kernel_cap_t *inheritable, kernel_cap_t *permitted)
2149{
2150 return avc_has_perm(&selinux_state,
2151 current_sid(), task_sid(target), SECCLASS_PROCESS,
2152 PROCESS__GETCAP, NULL);
2153}
2154
2155static int selinux_capset(struct cred *new, const struct cred *old,
2156 const kernel_cap_t *effective,
2157 const kernel_cap_t *inheritable,
2158 const kernel_cap_t *permitted)
2159{
2160 return avc_has_perm(&selinux_state,
2161 cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2162 PROCESS__SETCAP, NULL);
2163}
2164
2165/*
2166 * (This comment used to live with the selinux_task_setuid hook,
2167 * which was removed).
2168 *
2169 * Since setuid only affects the current process, and since the SELinux
2170 * controls are not based on the Linux identity attributes, SELinux does not
2171 * need to control this operation. However, SELinux does control the use of
2172 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2173 */
2174
2175static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2176 int cap, unsigned int opts)
2177{
2178 return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2179}
2180
2181static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2182{
2183 const struct cred *cred = current_cred();
2184 int rc = 0;
2185
2186 if (!sb)
2187 return 0;
2188
2189 switch (cmds) {
2190 case Q_SYNC:
2191 case Q_QUOTAON:
2192 case Q_QUOTAOFF:
2193 case Q_SETINFO:
2194 case Q_SETQUOTA:
2195 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2196 break;
2197 case Q_GETFMT:
2198 case Q_GETINFO:
2199 case Q_GETQUOTA:
2200 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2201 break;
2202 default:
2203 rc = 0; /* let the kernel handle invalid cmds */
2204 break;
2205 }
2206 return rc;
2207}
2208
2209static int selinux_quota_on(struct dentry *dentry)
2210{
2211 const struct cred *cred = current_cred();
2212
2213 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2214}
2215
2216static int selinux_syslog(int type)
2217{
2218 switch (type) {
2219 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2220 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2221 return avc_has_perm(&selinux_state,
2222 current_sid(), SECINITSID_KERNEL,
2223 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2224 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2225 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2226 /* Set level of messages printed to console */
2227 case SYSLOG_ACTION_CONSOLE_LEVEL:
2228 return avc_has_perm(&selinux_state,
2229 current_sid(), SECINITSID_KERNEL,
2230 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2231 NULL);
2232 }
2233 /* All other syslog types */
2234 return avc_has_perm(&selinux_state,
2235 current_sid(), SECINITSID_KERNEL,
2236 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2237}
2238
2239/*
2240 * Check that a process has enough memory to allocate a new virtual
2241 * mapping. 0 means there is enough memory for the allocation to
2242 * succeed and -ENOMEM implies there is not.
2243 *
2244 * Do not audit the selinux permission check, as this is applied to all
2245 * processes that allocate mappings.
2246 */
2247static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2248{
2249 int rc, cap_sys_admin = 0;
2250
2251 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2252 CAP_OPT_NOAUDIT, true);
2253 if (rc == 0)
2254 cap_sys_admin = 1;
2255
2256 return cap_sys_admin;
2257}
2258
2259/* binprm security operations */
2260
2261static u32 ptrace_parent_sid(void)
2262{
2263 u32 sid = 0;
2264 struct task_struct *tracer;
2265
2266 rcu_read_lock();
2267 tracer = ptrace_parent(current);
2268 if (tracer)
2269 sid = task_sid(tracer);
2270 rcu_read_unlock();
2271
2272 return sid;
2273}
2274
2275static int check_nnp_nosuid(const struct linux_binprm *bprm,
2276 const struct task_security_struct *old_tsec,
2277 const struct task_security_struct *new_tsec)
2278{
2279 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2280 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2281 int rc;
2282 u32 av;
2283
2284 if (!nnp && !nosuid)
2285 return 0; /* neither NNP nor nosuid */
2286
2287 if (new_tsec->sid == old_tsec->sid)
2288 return 0; /* No change in credentials */
2289
2290 /*
2291 * If the policy enables the nnp_nosuid_transition policy capability,
2292 * then we permit transitions under NNP or nosuid if the
2293 * policy allows the corresponding permission between
2294 * the old and new contexts.
2295 */
2296 if (selinux_policycap_nnp_nosuid_transition()) {
2297 av = 0;
2298 if (nnp)
2299 av |= PROCESS2__NNP_TRANSITION;
2300 if (nosuid)
2301 av |= PROCESS2__NOSUID_TRANSITION;
2302 rc = avc_has_perm(&selinux_state,
2303 old_tsec->sid, new_tsec->sid,
2304 SECCLASS_PROCESS2, av, NULL);
2305 if (!rc)
2306 return 0;
2307 }
2308
2309 /*
2310 * We also permit NNP or nosuid transitions to bounded SIDs,
2311 * i.e. SIDs that are guaranteed to only be allowed a subset
2312 * of the permissions of the current SID.
2313 */
2314 rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2315 new_tsec->sid);
2316 if (!rc)
2317 return 0;
2318
2319 /*
2320 * On failure, preserve the errno values for NNP vs nosuid.
2321 * NNP: Operation not permitted for caller.
2322 * nosuid: Permission denied to file.
2323 */
2324 if (nnp)
2325 return -EPERM;
2326 return -EACCES;
2327}
2328
2329static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2330{
2331 const struct task_security_struct *old_tsec;
2332 struct task_security_struct *new_tsec;
2333 struct inode_security_struct *isec;
2334 struct common_audit_data ad;
2335 struct inode *inode = file_inode(bprm->file);
2336 int rc;
2337
2338 /* SELinux context only depends on initial program or script and not
2339 * the script interpreter */
2340 if (bprm->called_set_creds)
2341 return 0;
2342
2343 old_tsec = selinux_cred(current_cred());
2344 new_tsec = selinux_cred(bprm->cred);
2345 isec = inode_security(inode);
2346
2347 /* Default to the current task SID. */
2348 new_tsec->sid = old_tsec->sid;
2349 new_tsec->osid = old_tsec->sid;
2350
2351 /* Reset fs, key, and sock SIDs on execve. */
2352 new_tsec->create_sid = 0;
2353 new_tsec->keycreate_sid = 0;
2354 new_tsec->sockcreate_sid = 0;
2355
2356 if (old_tsec->exec_sid) {
2357 new_tsec->sid = old_tsec->exec_sid;
2358 /* Reset exec SID on execve. */
2359 new_tsec->exec_sid = 0;
2360
2361 /* Fail on NNP or nosuid if not an allowed transition. */
2362 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2363 if (rc)
2364 return rc;
2365 } else {
2366 /* Check for a default transition on this program. */
2367 rc = security_transition_sid(&selinux_state, old_tsec->sid,
2368 isec->sid, SECCLASS_PROCESS, NULL,
2369 &new_tsec->sid);
2370 if (rc)
2371 return rc;
2372
2373 /*
2374 * Fallback to old SID on NNP or nosuid if not an allowed
2375 * transition.
2376 */
2377 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2378 if (rc)
2379 new_tsec->sid = old_tsec->sid;
2380 }
2381
2382 ad.type = LSM_AUDIT_DATA_FILE;
2383 ad.u.file = bprm->file;
2384
2385 if (new_tsec->sid == old_tsec->sid) {
2386 rc = avc_has_perm(&selinux_state,
2387 old_tsec->sid, isec->sid,
2388 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2389 if (rc)
2390 return rc;
2391 } else {
2392 /* Check permissions for the transition. */
2393 rc = avc_has_perm(&selinux_state,
2394 old_tsec->sid, new_tsec->sid,
2395 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2396 if (rc)
2397 return rc;
2398
2399 rc = avc_has_perm(&selinux_state,
2400 new_tsec->sid, isec->sid,
2401 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2402 if (rc)
2403 return rc;
2404
2405 /* Check for shared state */
2406 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2407 rc = avc_has_perm(&selinux_state,
2408 old_tsec->sid, new_tsec->sid,
2409 SECCLASS_PROCESS, PROCESS__SHARE,
2410 NULL);
2411 if (rc)
2412 return -EPERM;
2413 }
2414
2415 /* Make sure that anyone attempting to ptrace over a task that
2416 * changes its SID has the appropriate permit */
2417 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2418 u32 ptsid = ptrace_parent_sid();
2419 if (ptsid != 0) {
2420 rc = avc_has_perm(&selinux_state,
2421 ptsid, new_tsec->sid,
2422 SECCLASS_PROCESS,
2423 PROCESS__PTRACE, NULL);
2424 if (rc)
2425 return -EPERM;
2426 }
2427 }
2428
2429 /* Clear any possibly unsafe personality bits on exec: */
2430 bprm->per_clear |= PER_CLEAR_ON_SETID;
2431
2432 /* Enable secure mode for SIDs transitions unless
2433 the noatsecure permission is granted between
2434 the two SIDs, i.e. ahp returns 0. */
2435 rc = avc_has_perm(&selinux_state,
2436 old_tsec->sid, new_tsec->sid,
2437 SECCLASS_PROCESS, PROCESS__NOATSECURE,
2438 NULL);
2439 bprm->secureexec |= !!rc;
2440 }
2441
2442 return 0;
2443}
2444
2445static int match_file(const void *p, struct file *file, unsigned fd)
2446{
2447 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2448}
2449
2450/* Derived from fs/exec.c:flush_old_files. */
2451static inline void flush_unauthorized_files(const struct cred *cred,
2452 struct files_struct *files)
2453{
2454 struct file *file, *devnull = NULL;
2455 struct tty_struct *tty;
2456 int drop_tty = 0;
2457 unsigned n;
2458
2459 tty = get_current_tty();
2460 if (tty) {
2461 spin_lock(&tty->files_lock);
2462 if (!list_empty(&tty->tty_files)) {
2463 struct tty_file_private *file_priv;
2464
2465 /* Revalidate access to controlling tty.
2466 Use file_path_has_perm on the tty path directly
2467 rather than using file_has_perm, as this particular
2468 open file may belong to another process and we are
2469 only interested in the inode-based check here. */
2470 file_priv = list_first_entry(&tty->tty_files,
2471 struct tty_file_private, list);
2472 file = file_priv->file;
2473 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2474 drop_tty = 1;
2475 }
2476 spin_unlock(&tty->files_lock);
2477 tty_kref_put(tty);
2478 }
2479 /* Reset controlling tty. */
2480 if (drop_tty)
2481 no_tty();
2482
2483 /* Revalidate access to inherited open files. */
2484 n = iterate_fd(files, 0, match_file, cred);
2485 if (!n) /* none found? */
2486 return;
2487
2488 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2489 if (IS_ERR(devnull))
2490 devnull = NULL;
2491 /* replace all the matching ones with this */
2492 do {
2493 replace_fd(n - 1, devnull, 0);
2494 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2495 if (devnull)
2496 fput(devnull);
2497}
2498
2499/*
2500 * Prepare a process for imminent new credential changes due to exec
2501 */
2502static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2503{
2504 struct task_security_struct *new_tsec;
2505 struct rlimit *rlim, *initrlim;
2506 int rc, i;
2507
2508 new_tsec = selinux_cred(bprm->cred);
2509 if (new_tsec->sid == new_tsec->osid)
2510 return;
2511
2512 /* Close files for which the new task SID is not authorized. */
2513 flush_unauthorized_files(bprm->cred, current->files);
2514
2515 /* Always clear parent death signal on SID transitions. */
2516 current->pdeath_signal = 0;
2517
2518 /* Check whether the new SID can inherit resource limits from the old
2519 * SID. If not, reset all soft limits to the lower of the current
2520 * task's hard limit and the init task's soft limit.
2521 *
2522 * Note that the setting of hard limits (even to lower them) can be
2523 * controlled by the setrlimit check. The inclusion of the init task's
2524 * soft limit into the computation is to avoid resetting soft limits
2525 * higher than the default soft limit for cases where the default is
2526 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2527 */
2528 rc = avc_has_perm(&selinux_state,
2529 new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2530 PROCESS__RLIMITINH, NULL);
2531 if (rc) {
2532 /* protect against do_prlimit() */
2533 task_lock(current);
2534 for (i = 0; i < RLIM_NLIMITS; i++) {
2535 rlim = current->signal->rlim + i;
2536 initrlim = init_task.signal->rlim + i;
2537 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2538 }
2539 task_unlock(current);
2540 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2541 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2542 }
2543}
2544
2545/*
2546 * Clean up the process immediately after the installation of new credentials
2547 * due to exec
2548 */
2549static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2550{
2551 const struct task_security_struct *tsec = selinux_cred(current_cred());
2552 struct itimerval itimer;
2553 u32 osid, sid;
2554 int rc, i;
2555
2556 osid = tsec->osid;
2557 sid = tsec->sid;
2558
2559 if (sid == osid)
2560 return;
2561
2562 /* Check whether the new SID can inherit signal state from the old SID.
2563 * If not, clear itimers to avoid subsequent signal generation and
2564 * flush and unblock signals.
2565 *
2566 * This must occur _after_ the task SID has been updated so that any
2567 * kill done after the flush will be checked against the new SID.
2568 */
2569 rc = avc_has_perm(&selinux_state,
2570 osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2571 if (rc) {
2572 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) {
2573 memset(&itimer, 0, sizeof itimer);
2574 for (i = 0; i < 3; i++)
2575 do_setitimer(i, &itimer, NULL);
2576 }
2577 spin_lock_irq(¤t->sighand->siglock);
2578 if (!fatal_signal_pending(current)) {
2579 flush_sigqueue(¤t->pending);
2580 flush_sigqueue(¤t->signal->shared_pending);
2581 flush_signal_handlers(current, 1);
2582 sigemptyset(¤t->blocked);
2583 recalc_sigpending();
2584 }
2585 spin_unlock_irq(¤t->sighand->siglock);
2586 }
2587
2588 /* Wake up the parent if it is waiting so that it can recheck
2589 * wait permission to the new task SID. */
2590 read_lock(&tasklist_lock);
2591 __wake_up_parent(current, current->real_parent);
2592 read_unlock(&tasklist_lock);
2593}
2594
2595/* superblock security operations */
2596
2597static int selinux_sb_alloc_security(struct super_block *sb)
2598{
2599 return superblock_alloc_security(sb);
2600}
2601
2602static void selinux_sb_free_security(struct super_block *sb)
2603{
2604 superblock_free_security(sb);
2605}
2606
2607static inline int opt_len(const char *s)
2608{
2609 bool open_quote = false;
2610 int len;
2611 char c;
2612
2613 for (len = 0; (c = s[len]) != '\0'; len++) {
2614 if (c == '"')
2615 open_quote = !open_quote;
2616 if (c == ',' && !open_quote)
2617 break;
2618 }
2619 return len;
2620}
2621
2622static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2623{
2624 char *from = options;
2625 char *to = options;
2626 bool first = true;
2627 int rc;
2628
2629 while (1) {
2630 int len = opt_len(from);
2631 int token;
2632 char *arg = NULL;
2633
2634 token = match_opt_prefix(from, len, &arg);
2635
2636 if (token != Opt_error) {
2637 char *p, *q;
2638
2639 /* strip quotes */
2640 if (arg) {
2641 for (p = q = arg; p < from + len; p++) {
2642 char c = *p;
2643 if (c != '"')
2644 *q++ = c;
2645 }
2646 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2647 if (!arg) {
2648 rc = -ENOMEM;
2649 goto free_opt;
2650 }
2651 }
2652 rc = selinux_add_opt(token, arg, mnt_opts);
2653 if (unlikely(rc)) {
2654 kfree(arg);
2655 goto free_opt;
2656 }
2657 } else {
2658 if (!first) { // copy with preceding comma
2659 from--;
2660 len++;
2661 }
2662 if (to != from)
2663 memmove(to, from, len);
2664 to += len;
2665 first = false;
2666 }
2667 if (!from[len])
2668 break;
2669 from += len + 1;
2670 }
2671 *to = '\0';
2672 return 0;
2673
2674free_opt:
2675 if (*mnt_opts) {
2676 selinux_free_mnt_opts(*mnt_opts);
2677 *mnt_opts = NULL;
2678 }
2679 return rc;
2680}
2681
2682static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2683{
2684 struct selinux_mnt_opts *opts = mnt_opts;
2685 struct superblock_security_struct *sbsec = sb->s_security;
2686 u32 sid;
2687 int rc;
2688
2689 if (!(sbsec->flags & SE_SBINITIALIZED))
2690 return 0;
2691
2692 if (!opts)
2693 return 0;
2694
2695 if (opts->fscontext) {
2696 rc = parse_sid(sb, opts->fscontext, &sid);
2697 if (rc)
2698 return rc;
2699 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2700 goto out_bad_option;
2701 }
2702 if (opts->context) {
2703 rc = parse_sid(sb, opts->context, &sid);
2704 if (rc)
2705 return rc;
2706 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2707 goto out_bad_option;
2708 }
2709 if (opts->rootcontext) {
2710 struct inode_security_struct *root_isec;
2711 root_isec = backing_inode_security(sb->s_root);
2712 rc = parse_sid(sb, opts->rootcontext, &sid);
2713 if (rc)
2714 return rc;
2715 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2716 goto out_bad_option;
2717 }
2718 if (opts->defcontext) {
2719 rc = parse_sid(sb, opts->defcontext, &sid);
2720 if (rc)
2721 return rc;
2722 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2723 goto out_bad_option;
2724 }
2725 return 0;
2726
2727out_bad_option:
2728 pr_warn("SELinux: unable to change security options "
2729 "during remount (dev %s, type=%s)\n", sb->s_id,
2730 sb->s_type->name);
2731 return -EINVAL;
2732}
2733
2734static int selinux_sb_kern_mount(struct super_block *sb)
2735{
2736 const struct cred *cred = current_cred();
2737 struct common_audit_data ad;
2738
2739 ad.type = LSM_AUDIT_DATA_DENTRY;
2740 ad.u.dentry = sb->s_root;
2741 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2742}
2743
2744static int selinux_sb_statfs(struct dentry *dentry)
2745{
2746 const struct cred *cred = current_cred();
2747 struct common_audit_data ad;
2748
2749 ad.type = LSM_AUDIT_DATA_DENTRY;
2750 ad.u.dentry = dentry->d_sb->s_root;
2751 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2752}
2753
2754static int selinux_mount(const char *dev_name,
2755 const struct path *path,
2756 const char *type,
2757 unsigned long flags,
2758 void *data)
2759{
2760 const struct cred *cred = current_cred();
2761
2762 if (flags & MS_REMOUNT)
2763 return superblock_has_perm(cred, path->dentry->d_sb,
2764 FILESYSTEM__REMOUNT, NULL);
2765 else
2766 return path_has_perm(cred, path, FILE__MOUNTON);
2767}
2768
2769static int selinux_umount(struct vfsmount *mnt, int flags)
2770{
2771 const struct cred *cred = current_cred();
2772
2773 return superblock_has_perm(cred, mnt->mnt_sb,
2774 FILESYSTEM__UNMOUNT, NULL);
2775}
2776
2777static int selinux_fs_context_dup(struct fs_context *fc,
2778 struct fs_context *src_fc)
2779{
2780 const struct selinux_mnt_opts *src = src_fc->security;
2781 struct selinux_mnt_opts *opts;
2782
2783 if (!src)
2784 return 0;
2785
2786 fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
2787 if (!fc->security)
2788 return -ENOMEM;
2789
2790 opts = fc->security;
2791
2792 if (src->fscontext) {
2793 opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL);
2794 if (!opts->fscontext)
2795 return -ENOMEM;
2796 }
2797 if (src->context) {
2798 opts->context = kstrdup(src->context, GFP_KERNEL);
2799 if (!opts->context)
2800 return -ENOMEM;
2801 }
2802 if (src->rootcontext) {
2803 opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL);
2804 if (!opts->rootcontext)
2805 return -ENOMEM;
2806 }
2807 if (src->defcontext) {
2808 opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL);
2809 if (!opts->defcontext)
2810 return -ENOMEM;
2811 }
2812 return 0;
2813}
2814
2815static const struct fs_parameter_spec selinux_param_specs[] = {
2816 fsparam_string(CONTEXT_STR, Opt_context),
2817 fsparam_string(DEFCONTEXT_STR, Opt_defcontext),
2818 fsparam_string(FSCONTEXT_STR, Opt_fscontext),
2819 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2820 fsparam_flag (SECLABEL_STR, Opt_seclabel),
2821 {}
2822};
2823
2824static const struct fs_parameter_description selinux_fs_parameters = {
2825 .name = "SELinux",
2826 .specs = selinux_param_specs,
2827};
2828
2829static int selinux_fs_context_parse_param(struct fs_context *fc,
2830 struct fs_parameter *param)
2831{
2832 struct fs_parse_result result;
2833 int opt, rc;
2834
2835 opt = fs_parse(fc, &selinux_fs_parameters, param, &result);
2836 if (opt < 0)
2837 return opt;
2838
2839 rc = selinux_add_opt(opt, param->string, &fc->security);
2840 if (!rc) {
2841 param->string = NULL;
2842 rc = 1;
2843 }
2844 return rc;
2845}
2846
2847/* inode security operations */
2848
2849static int selinux_inode_alloc_security(struct inode *inode)
2850{
2851 return inode_alloc_security(inode);
2852}
2853
2854static void selinux_inode_free_security(struct inode *inode)
2855{
2856 inode_free_security(inode);
2857}
2858
2859static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2860 const struct qstr *name, void **ctx,
2861 u32 *ctxlen)
2862{
2863 u32 newsid;
2864 int rc;
2865
2866 rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2867 d_inode(dentry->d_parent), name,
2868 inode_mode_to_security_class(mode),
2869 &newsid);
2870 if (rc)
2871 return rc;
2872
2873 return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
2874 ctxlen);
2875}
2876
2877static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2878 struct qstr *name,
2879 const struct cred *old,
2880 struct cred *new)
2881{
2882 u32 newsid;
2883 int rc;
2884 struct task_security_struct *tsec;
2885
2886 rc = selinux_determine_inode_label(selinux_cred(old),
2887 d_inode(dentry->d_parent), name,
2888 inode_mode_to_security_class(mode),
2889 &newsid);
2890 if (rc)
2891 return rc;
2892
2893 tsec = selinux_cred(new);
2894 tsec->create_sid = newsid;
2895 return 0;
2896}
2897
2898static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2899 const struct qstr *qstr,
2900 const char **name,
2901 void **value, size_t *len)
2902{
2903 const struct task_security_struct *tsec = selinux_cred(current_cred());
2904 struct superblock_security_struct *sbsec;
2905 u32 newsid, clen;
2906 int rc;
2907 char *context;
2908
2909 sbsec = dir->i_sb->s_security;
2910
2911 newsid = tsec->create_sid;
2912
2913 rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2914 dir, qstr,
2915 inode_mode_to_security_class(inode->i_mode),
2916 &newsid);
2917 if (rc)
2918 return rc;
2919
2920 /* Possibly defer initialization to selinux_complete_init. */
2921 if (sbsec->flags & SE_SBINITIALIZED) {
2922 struct inode_security_struct *isec = selinux_inode(inode);
2923 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2924 isec->sid = newsid;
2925 isec->initialized = LABEL_INITIALIZED;
2926 }
2927
2928 if (!selinux_state.initialized || !(sbsec->flags & SBLABEL_MNT))
2929 return -EOPNOTSUPP;
2930
2931 if (name)
2932 *name = XATTR_SELINUX_SUFFIX;
2933
2934 if (value && len) {
2935 rc = security_sid_to_context_force(&selinux_state, newsid,
2936 &context, &clen);
2937 if (rc)
2938 return rc;
2939 *value = context;
2940 *len = clen;
2941 }
2942
2943 return 0;
2944}
2945
2946static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2947{
2948 return may_create(dir, dentry, SECCLASS_FILE);
2949}
2950
2951static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2952{
2953 return may_link(dir, old_dentry, MAY_LINK);
2954}
2955
2956static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2957{
2958 return may_link(dir, dentry, MAY_UNLINK);
2959}
2960
2961static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2962{
2963 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2964}
2965
2966static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2967{
2968 return may_create(dir, dentry, SECCLASS_DIR);
2969}
2970
2971static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2972{
2973 return may_link(dir, dentry, MAY_RMDIR);
2974}
2975
2976static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2977{
2978 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2979}
2980
2981static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2982 struct inode *new_inode, struct dentry *new_dentry)
2983{
2984 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2985}
2986
2987static int selinux_inode_readlink(struct dentry *dentry)
2988{
2989 const struct cred *cred = current_cred();
2990
2991 return dentry_has_perm(cred, dentry, FILE__READ);
2992}
2993
2994static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2995 bool rcu)
2996{
2997 const struct cred *cred = current_cred();
2998 struct common_audit_data ad;
2999 struct inode_security_struct *isec;
3000 u32 sid;
3001
3002 validate_creds(cred);
3003
3004 ad.type = LSM_AUDIT_DATA_DENTRY;
3005 ad.u.dentry = dentry;
3006 sid = cred_sid(cred);
3007 isec = inode_security_rcu(inode, rcu);
3008 if (IS_ERR(isec))
3009 return PTR_ERR(isec);
3010
3011 return avc_has_perm(&selinux_state,
3012 sid, isec->sid, isec->sclass, FILE__READ, &ad);
3013}
3014
3015static noinline int audit_inode_permission(struct inode *inode,
3016 u32 perms, u32 audited, u32 denied,
3017 int result,
3018 unsigned flags)
3019{
3020 struct common_audit_data ad;
3021 struct inode_security_struct *isec = selinux_inode(inode);
3022 int rc;
3023
3024 ad.type = LSM_AUDIT_DATA_INODE;
3025 ad.u.inode = inode;
3026
3027 rc = slow_avc_audit(&selinux_state,
3028 current_sid(), isec->sid, isec->sclass, perms,
3029 audited, denied, result, &ad, flags);
3030 if (rc)
3031 return rc;
3032 return 0;
3033}
3034
3035static int selinux_inode_permission(struct inode *inode, int mask)
3036{
3037 const struct cred *cred = current_cred();
3038 u32 perms;
3039 bool from_access;
3040 unsigned flags = mask & MAY_NOT_BLOCK;
3041 struct inode_security_struct *isec;
3042 u32 sid;
3043 struct av_decision avd;
3044 int rc, rc2;
3045 u32 audited, denied;
3046
3047 from_access = mask & MAY_ACCESS;
3048 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3049
3050 /* No permission to check. Existence test. */
3051 if (!mask)
3052 return 0;
3053
3054 validate_creds(cred);
3055
3056 if (unlikely(IS_PRIVATE(inode)))
3057 return 0;
3058
3059 perms = file_mask_to_av(inode->i_mode, mask);
3060
3061 sid = cred_sid(cred);
3062 isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
3063 if (IS_ERR(isec))
3064 return PTR_ERR(isec);
3065
3066 rc = avc_has_perm_noaudit(&selinux_state,
3067 sid, isec->sid, isec->sclass, perms,
3068 (flags & MAY_NOT_BLOCK) ? AVC_NONBLOCKING : 0,
3069 &avd);
3070 audited = avc_audit_required(perms, &avd, rc,
3071 from_access ? FILE__AUDIT_ACCESS : 0,
3072 &denied);
3073 if (likely(!audited))
3074 return rc;
3075
3076 rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
3077 if (rc2)
3078 return rc2;
3079 return rc;
3080}
3081
3082static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3083{
3084 const struct cred *cred = current_cred();
3085 struct inode *inode = d_backing_inode(dentry);
3086 unsigned int ia_valid = iattr->ia_valid;
3087 __u32 av = FILE__WRITE;
3088
3089 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3090 if (ia_valid & ATTR_FORCE) {
3091 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3092 ATTR_FORCE);
3093 if (!ia_valid)
3094 return 0;
3095 }
3096
3097 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3098 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3099 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3100
3101 if (selinux_policycap_openperm() &&
3102 inode->i_sb->s_magic != SOCKFS_MAGIC &&
3103 (ia_valid & ATTR_SIZE) &&
3104 !(ia_valid & ATTR_FILE))
3105 av |= FILE__OPEN;
3106
3107 return dentry_has_perm(cred, dentry, av);
3108}
3109
3110static int selinux_inode_getattr(const struct path *path)
3111{
3112 return path_has_perm(current_cred(), path, FILE__GETATTR);
3113}
3114
3115static bool has_cap_mac_admin(bool audit)
3116{
3117 const struct cred *cred = current_cred();
3118 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3119
3120 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3121 return false;
3122 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3123 return false;
3124 return true;
3125}
3126
3127static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3128 const void *value, size_t size, int flags)
3129{
3130 struct inode *inode = d_backing_inode(dentry);
3131 struct inode_security_struct *isec;
3132 struct superblock_security_struct *sbsec;
3133 struct common_audit_data ad;
3134 u32 newsid, sid = current_sid();
3135 int rc = 0;
3136
3137 if (strcmp(name, XATTR_NAME_SELINUX)) {
3138 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3139 if (rc)
3140 return rc;
3141
3142 /* Not an attribute we recognize, so just check the
3143 ordinary setattr permission. */
3144 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3145 }
3146
3147 sbsec = inode->i_sb->s_security;
3148 if (!(sbsec->flags & SBLABEL_MNT))
3149 return -EOPNOTSUPP;
3150
3151 if (!inode_owner_or_capable(inode))
3152 return -EPERM;
3153
3154 ad.type = LSM_AUDIT_DATA_DENTRY;
3155 ad.u.dentry = dentry;
3156
3157 isec = backing_inode_security(dentry);
3158 rc = avc_has_perm(&selinux_state,
3159 sid, isec->sid, isec->sclass,
3160 FILE__RELABELFROM, &ad);
3161 if (rc)
3162 return rc;
3163
3164 rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3165 GFP_KERNEL);
3166 if (rc == -EINVAL) {
3167 if (!has_cap_mac_admin(true)) {
3168 struct audit_buffer *ab;
3169 size_t audit_size;
3170
3171 /* We strip a nul only if it is at the end, otherwise the
3172 * context contains a nul and we should audit that */
3173 if (value) {
3174 const char *str = value;
3175
3176 if (str[size - 1] == '\0')
3177 audit_size = size - 1;
3178 else
3179 audit_size = size;
3180 } else {
3181 audit_size = 0;
3182 }
3183 ab = audit_log_start(audit_context(),
3184 GFP_ATOMIC, AUDIT_SELINUX_ERR);
3185 audit_log_format(ab, "op=setxattr invalid_context=");
3186 audit_log_n_untrustedstring(ab, value, audit_size);
3187 audit_log_end(ab);
3188
3189 return rc;
3190 }
3191 rc = security_context_to_sid_force(&selinux_state, value,
3192 size, &newsid);
3193 }
3194 if (rc)
3195 return rc;
3196
3197 rc = avc_has_perm(&selinux_state,
3198 sid, newsid, isec->sclass,
3199 FILE__RELABELTO, &ad);
3200 if (rc)
3201 return rc;
3202
3203 rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3204 sid, isec->sclass);
3205 if (rc)
3206 return rc;
3207
3208 return avc_has_perm(&selinux_state,
3209 newsid,
3210 sbsec->sid,
3211 SECCLASS_FILESYSTEM,
3212 FILESYSTEM__ASSOCIATE,
3213 &ad);
3214}
3215
3216static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3217 const void *value, size_t size,
3218 int flags)
3219{
3220 struct inode *inode = d_backing_inode(dentry);
3221 struct inode_security_struct *isec;
3222 u32 newsid;
3223 int rc;
3224
3225 if (strcmp(name, XATTR_NAME_SELINUX)) {
3226 /* Not an attribute we recognize, so nothing to do. */
3227 return;
3228 }
3229
3230 rc = security_context_to_sid_force(&selinux_state, value, size,
3231 &newsid);
3232 if (rc) {
3233 pr_err("SELinux: unable to map context to SID"
3234 "for (%s, %lu), rc=%d\n",
3235 inode->i_sb->s_id, inode->i_ino, -rc);
3236 return;
3237 }
3238
3239 isec = backing_inode_security(dentry);
3240 spin_lock(&isec->lock);
3241 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3242 isec->sid = newsid;
3243 isec->initialized = LABEL_INITIALIZED;
3244 spin_unlock(&isec->lock);
3245
3246 return;
3247}
3248
3249static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3250{
3251 const struct cred *cred = current_cred();
3252
3253 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3254}
3255
3256static int selinux_inode_listxattr(struct dentry *dentry)
3257{
3258 const struct cred *cred = current_cred();
3259
3260 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3261}
3262
3263static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3264{
3265 if (strcmp(name, XATTR_NAME_SELINUX)) {
3266 int rc = cap_inode_removexattr(dentry, name);
3267 if (rc)
3268 return rc;
3269
3270 /* Not an attribute we recognize, so just check the
3271 ordinary setattr permission. */
3272 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3273 }
3274
3275 /* No one is allowed to remove a SELinux security label.
3276 You can change the label, but all data must be labeled. */
3277 return -EACCES;
3278}
3279
3280static int selinux_path_notify(const struct path *path, u64 mask,
3281 unsigned int obj_type)
3282{
3283 int ret;
3284 u32 perm;
3285
3286 struct common_audit_data ad;
3287
3288 ad.type = LSM_AUDIT_DATA_PATH;
3289 ad.u.path = *path;
3290
3291 /*
3292 * Set permission needed based on the type of mark being set.
3293 * Performs an additional check for sb watches.
3294 */
3295 switch (obj_type) {
3296 case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3297 perm = FILE__WATCH_MOUNT;
3298 break;
3299 case FSNOTIFY_OBJ_TYPE_SB:
3300 perm = FILE__WATCH_SB;
3301 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3302 FILESYSTEM__WATCH, &ad);
3303 if (ret)
3304 return ret;
3305 break;
3306 case FSNOTIFY_OBJ_TYPE_INODE:
3307 perm = FILE__WATCH;
3308 break;
3309 default:
3310 return -EINVAL;
3311 }
3312
3313 /* blocking watches require the file:watch_with_perm permission */
3314 if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3315 perm |= FILE__WATCH_WITH_PERM;
3316
3317 /* watches on read-like events need the file:watch_reads permission */
3318 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3319 perm |= FILE__WATCH_READS;
3320
3321 return path_has_perm(current_cred(), path, perm);
3322}
3323
3324/*
3325 * Copy the inode security context value to the user.
3326 *
3327 * Permission check is handled by selinux_inode_getxattr hook.
3328 */
3329static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3330{
3331 u32 size;
3332 int error;
3333 char *context = NULL;
3334 struct inode_security_struct *isec;
3335
3336 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3337 return -EOPNOTSUPP;
3338
3339 /*
3340 * If the caller has CAP_MAC_ADMIN, then get the raw context
3341 * value even if it is not defined by current policy; otherwise,
3342 * use the in-core value under current policy.
3343 * Use the non-auditing forms of the permission checks since
3344 * getxattr may be called by unprivileged processes commonly
3345 * and lack of permission just means that we fall back to the
3346 * in-core context value, not a denial.
3347 */
3348 isec = inode_security(inode);
3349 if (has_cap_mac_admin(false))
3350 error = security_sid_to_context_force(&selinux_state,
3351 isec->sid, &context,
3352 &size);
3353 else
3354 error = security_sid_to_context(&selinux_state, isec->sid,
3355 &context, &size);
3356 if (error)
3357 return error;
3358 error = size;
3359 if (alloc) {
3360 *buffer = context;
3361 goto out_nofree;
3362 }
3363 kfree(context);
3364out_nofree:
3365 return error;
3366}
3367
3368static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3369 const void *value, size_t size, int flags)
3370{
3371 struct inode_security_struct *isec = inode_security_novalidate(inode);
3372 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
3373 u32 newsid;
3374 int rc;
3375
3376 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3377 return -EOPNOTSUPP;
3378
3379 if (!(sbsec->flags & SBLABEL_MNT))
3380 return -EOPNOTSUPP;
3381
3382 if (!value || !size)
3383 return -EACCES;
3384
3385 rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3386 GFP_KERNEL);
3387 if (rc)
3388 return rc;
3389
3390 spin_lock(&isec->lock);
3391 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3392 isec->sid = newsid;
3393 isec->initialized = LABEL_INITIALIZED;
3394 spin_unlock(&isec->lock);
3395 return 0;
3396}
3397
3398static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3399{
3400 const int len = sizeof(XATTR_NAME_SELINUX);
3401 if (buffer && len <= buffer_size)
3402 memcpy(buffer, XATTR_NAME_SELINUX, len);
3403 return len;
3404}
3405
3406static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3407{
3408 struct inode_security_struct *isec = inode_security_novalidate(inode);
3409 *secid = isec->sid;
3410}
3411
3412static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3413{
3414 u32 sid;
3415 struct task_security_struct *tsec;
3416 struct cred *new_creds = *new;
3417
3418 if (new_creds == NULL) {
3419 new_creds = prepare_creds();
3420 if (!new_creds)
3421 return -ENOMEM;
3422 }
3423
3424 tsec = selinux_cred(new_creds);
3425 /* Get label from overlay inode and set it in create_sid */
3426 selinux_inode_getsecid(d_inode(src), &sid);
3427 tsec->create_sid = sid;
3428 *new = new_creds;
3429 return 0;
3430}
3431
3432static int selinux_inode_copy_up_xattr(const char *name)
3433{
3434 /* The copy_up hook above sets the initial context on an inode, but we
3435 * don't then want to overwrite it by blindly copying all the lower
3436 * xattrs up. Instead, we have to filter out SELinux-related xattrs.
3437 */
3438 if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3439 return 1; /* Discard */
3440 /*
3441 * Any other attribute apart from SELINUX is not claimed, supported
3442 * by selinux.
3443 */
3444 return -EOPNOTSUPP;
3445}
3446
3447/* kernfs node operations */
3448
3449static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3450 struct kernfs_node *kn)
3451{
3452 const struct task_security_struct *tsec = selinux_cred(current_cred());
3453 u32 parent_sid, newsid, clen;
3454 int rc;
3455 char *context;
3456
3457 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3458 if (rc == -ENODATA)
3459 return 0;
3460 else if (rc < 0)
3461 return rc;
3462
3463 clen = (u32)rc;
3464 context = kmalloc(clen, GFP_KERNEL);
3465 if (!context)
3466 return -ENOMEM;
3467
3468 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3469 if (rc < 0) {
3470 kfree(context);
3471 return rc;
3472 }
3473
3474 rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid,
3475 GFP_KERNEL);
3476 kfree(context);
3477 if (rc)
3478 return rc;
3479
3480 if (tsec->create_sid) {
3481 newsid = tsec->create_sid;
3482 } else {
3483 u16 secclass = inode_mode_to_security_class(kn->mode);
3484 struct qstr q;
3485
3486 q.name = kn->name;
3487 q.hash_len = hashlen_string(kn_dir, kn->name);
3488
3489 rc = security_transition_sid(&selinux_state, tsec->sid,
3490 parent_sid, secclass, &q,
3491 &newsid);
3492 if (rc)
3493 return rc;
3494 }
3495
3496 rc = security_sid_to_context_force(&selinux_state, newsid,
3497 &context, &clen);
3498 if (rc)
3499 return rc;
3500
3501 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3502 XATTR_CREATE);
3503 kfree(context);
3504 return rc;
3505}
3506
3507
3508/* file security operations */
3509
3510static int selinux_revalidate_file_permission(struct file *file, int mask)
3511{
3512 const struct cred *cred = current_cred();
3513 struct inode *inode = file_inode(file);
3514
3515 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3516 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3517 mask |= MAY_APPEND;
3518
3519 return file_has_perm(cred, file,
3520 file_mask_to_av(inode->i_mode, mask));
3521}
3522
3523static int selinux_file_permission(struct file *file, int mask)
3524{
3525 struct inode *inode = file_inode(file);
3526 struct file_security_struct *fsec = selinux_file(file);
3527 struct inode_security_struct *isec;
3528 u32 sid = current_sid();
3529
3530 if (!mask)
3531 /* No permission to check. Existence test. */
3532 return 0;
3533
3534 isec = inode_security(inode);
3535 if (sid == fsec->sid && fsec->isid == isec->sid &&
3536 fsec->pseqno == avc_policy_seqno(&selinux_state))
3537 /* No change since file_open check. */
3538 return 0;
3539
3540 return selinux_revalidate_file_permission(file, mask);
3541}
3542
3543static int selinux_file_alloc_security(struct file *file)
3544{
3545 return file_alloc_security(file);
3546}
3547
3548/*
3549 * Check whether a task has the ioctl permission and cmd
3550 * operation to an inode.
3551 */
3552static int ioctl_has_perm(const struct cred *cred, struct file *file,
3553 u32 requested, u16 cmd)
3554{
3555 struct common_audit_data ad;
3556 struct file_security_struct *fsec = selinux_file(file);
3557 struct inode *inode = file_inode(file);
3558 struct inode_security_struct *isec;
3559 struct lsm_ioctlop_audit ioctl;
3560 u32 ssid = cred_sid(cred);
3561 int rc;
3562 u8 driver = cmd >> 8;
3563 u8 xperm = cmd & 0xff;
3564
3565 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3566 ad.u.op = &ioctl;
3567 ad.u.op->cmd = cmd;
3568 ad.u.op->path = file->f_path;
3569
3570 if (ssid != fsec->sid) {
3571 rc = avc_has_perm(&selinux_state,
3572 ssid, fsec->sid,
3573 SECCLASS_FD,
3574 FD__USE,
3575 &ad);
3576 if (rc)
3577 goto out;
3578 }
3579
3580 if (unlikely(IS_PRIVATE(inode)))
3581 return 0;
3582
3583 isec = inode_security(inode);
3584 rc = avc_has_extended_perms(&selinux_state,
3585 ssid, isec->sid, isec->sclass,
3586 requested, driver, xperm, &ad);
3587out:
3588 return rc;
3589}
3590
3591static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3592 unsigned long arg)
3593{
3594 const struct cred *cred = current_cred();
3595 int error = 0;
3596
3597 switch (cmd) {
3598 case FIONREAD:
3599 /* fall through */
3600 case FIBMAP:
3601 /* fall through */
3602 case FIGETBSZ:
3603 /* fall through */
3604 case FS_IOC_GETFLAGS:
3605 /* fall through */
3606 case FS_IOC_GETVERSION:
3607 error = file_has_perm(cred, file, FILE__GETATTR);
3608 break;
3609
3610 case FS_IOC_SETFLAGS:
3611 /* fall through */
3612 case FS_IOC_SETVERSION:
3613 error = file_has_perm(cred, file, FILE__SETATTR);
3614 break;
3615
3616 /* sys_ioctl() checks */
3617 case FIONBIO:
3618 /* fall through */
3619 case FIOASYNC:
3620 error = file_has_perm(cred, file, 0);
3621 break;
3622
3623 case KDSKBENT:
3624 case KDSKBSENT:
3625 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3626 CAP_OPT_NONE, true);
3627 break;
3628
3629 /* default case assumes that the command will go
3630 * to the file's ioctl() function.
3631 */
3632 default:
3633 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3634 }
3635 return error;
3636}
3637
3638static int default_noexec;
3639
3640static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3641{
3642 const struct cred *cred = current_cred();
3643 u32 sid = cred_sid(cred);
3644 int rc = 0;
3645
3646 if (default_noexec &&
3647 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3648 (!shared && (prot & PROT_WRITE)))) {
3649 /*
3650 * We are making executable an anonymous mapping or a
3651 * private file mapping that will also be writable.
3652 * This has an additional check.
3653 */
3654 rc = avc_has_perm(&selinux_state,
3655 sid, sid, SECCLASS_PROCESS,
3656 PROCESS__EXECMEM, NULL);
3657 if (rc)
3658 goto error;
3659 }
3660
3661 if (file) {
3662 /* read access is always possible with a mapping */
3663 u32 av = FILE__READ;
3664
3665 /* write access only matters if the mapping is shared */
3666 if (shared && (prot & PROT_WRITE))
3667 av |= FILE__WRITE;
3668
3669 if (prot & PROT_EXEC)
3670 av |= FILE__EXECUTE;
3671
3672 return file_has_perm(cred, file, av);
3673 }
3674
3675error:
3676 return rc;
3677}
3678
3679static int selinux_mmap_addr(unsigned long addr)
3680{
3681 int rc = 0;
3682
3683 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3684 u32 sid = current_sid();
3685 rc = avc_has_perm(&selinux_state,
3686 sid, sid, SECCLASS_MEMPROTECT,
3687 MEMPROTECT__MMAP_ZERO, NULL);
3688 }
3689
3690 return rc;
3691}
3692
3693static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3694 unsigned long prot, unsigned long flags)
3695{
3696 struct common_audit_data ad;
3697 int rc;
3698
3699 if (file) {
3700 ad.type = LSM_AUDIT_DATA_FILE;
3701 ad.u.file = file;
3702 rc = inode_has_perm(current_cred(), file_inode(file),
3703 FILE__MAP, &ad);
3704 if (rc)
3705 return rc;
3706 }
3707
3708 if (selinux_state.checkreqprot)
3709 prot = reqprot;
3710
3711 return file_map_prot_check(file, prot,
3712 (flags & MAP_TYPE) == MAP_SHARED);
3713}
3714
3715static int selinux_file_mprotect(struct vm_area_struct *vma,
3716 unsigned long reqprot,
3717 unsigned long prot)
3718{
3719 const struct cred *cred = current_cred();
3720 u32 sid = cred_sid(cred);
3721
3722 if (selinux_state.checkreqprot)
3723 prot = reqprot;
3724
3725 if (default_noexec &&
3726 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3727 int rc = 0;
3728 if (vma->vm_start >= vma->vm_mm->start_brk &&
3729 vma->vm_end <= vma->vm_mm->brk) {
3730 rc = avc_has_perm(&selinux_state,
3731 sid, sid, SECCLASS_PROCESS,
3732 PROCESS__EXECHEAP, NULL);
3733 } else if (!vma->vm_file &&
3734 ((vma->vm_start <= vma->vm_mm->start_stack &&
3735 vma->vm_end >= vma->vm_mm->start_stack) ||
3736 vma_is_stack_for_current(vma))) {
3737 rc = avc_has_perm(&selinux_state,
3738 sid, sid, SECCLASS_PROCESS,
3739 PROCESS__EXECSTACK, NULL);
3740 } else if (vma->vm_file && vma->anon_vma) {
3741 /*
3742 * We are making executable a file mapping that has
3743 * had some COW done. Since pages might have been
3744 * written, check ability to execute the possibly
3745 * modified content. This typically should only
3746 * occur for text relocations.
3747 */
3748 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3749 }
3750 if (rc)
3751 return rc;
3752 }
3753
3754 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3755}
3756
3757static int selinux_file_lock(struct file *file, unsigned int cmd)
3758{
3759 const struct cred *cred = current_cred();
3760
3761 return file_has_perm(cred, file, FILE__LOCK);
3762}
3763
3764static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3765 unsigned long arg)
3766{
3767 const struct cred *cred = current_cred();
3768 int err = 0;
3769
3770 switch (cmd) {
3771 case F_SETFL:
3772 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3773 err = file_has_perm(cred, file, FILE__WRITE);
3774 break;
3775 }
3776 /* fall through */
3777 case F_SETOWN:
3778 case F_SETSIG:
3779 case F_GETFL:
3780 case F_GETOWN:
3781 case F_GETSIG:
3782 case F_GETOWNER_UIDS:
3783 /* Just check FD__USE permission */
3784 err = file_has_perm(cred, file, 0);
3785 break;
3786 case F_GETLK:
3787 case F_SETLK:
3788 case F_SETLKW:
3789 case F_OFD_GETLK:
3790 case F_OFD_SETLK:
3791 case F_OFD_SETLKW:
3792#if BITS_PER_LONG == 32
3793 case F_GETLK64:
3794 case F_SETLK64:
3795 case F_SETLKW64:
3796#endif
3797 err = file_has_perm(cred, file, FILE__LOCK);
3798 break;
3799 }
3800
3801 return err;
3802}
3803
3804static void selinux_file_set_fowner(struct file *file)
3805{
3806 struct file_security_struct *fsec;
3807
3808 fsec = selinux_file(file);
3809 fsec->fown_sid = current_sid();
3810}
3811
3812static int selinux_file_send_sigiotask(struct task_struct *tsk,
3813 struct fown_struct *fown, int signum)
3814{
3815 struct file *file;
3816 u32 sid = task_sid(tsk);
3817 u32 perm;
3818 struct file_security_struct *fsec;
3819
3820 /* struct fown_struct is never outside the context of a struct file */
3821 file = container_of(fown, struct file, f_owner);
3822
3823 fsec = selinux_file(file);
3824
3825 if (!signum)
3826 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3827 else
3828 perm = signal_to_av(signum);
3829
3830 return avc_has_perm(&selinux_state,
3831 fsec->fown_sid, sid,
3832 SECCLASS_PROCESS, perm, NULL);
3833}
3834
3835static int selinux_file_receive(struct file *file)
3836{
3837 const struct cred *cred = current_cred();
3838
3839 return file_has_perm(cred, file, file_to_av(file));
3840}
3841
3842static int selinux_file_open(struct file *file)
3843{
3844 struct file_security_struct *fsec;
3845 struct inode_security_struct *isec;
3846
3847 fsec = selinux_file(file);
3848 isec = inode_security(file_inode(file));
3849 /*
3850 * Save inode label and policy sequence number
3851 * at open-time so that selinux_file_permission
3852 * can determine whether revalidation is necessary.
3853 * Task label is already saved in the file security
3854 * struct as its SID.
3855 */
3856 fsec->isid = isec->sid;
3857 fsec->pseqno = avc_policy_seqno(&selinux_state);
3858 /*
3859 * Since the inode label or policy seqno may have changed
3860 * between the selinux_inode_permission check and the saving
3861 * of state above, recheck that access is still permitted.
3862 * Otherwise, access might never be revalidated against the
3863 * new inode label or new policy.
3864 * This check is not redundant - do not remove.
3865 */
3866 return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3867}
3868
3869/* task security operations */
3870
3871static int selinux_task_alloc(struct task_struct *task,
3872 unsigned long clone_flags)
3873{
3874 u32 sid = current_sid();
3875
3876 return avc_has_perm(&selinux_state,
3877 sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3878}
3879
3880/*
3881 * prepare a new set of credentials for modification
3882 */
3883static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3884 gfp_t gfp)
3885{
3886 const struct task_security_struct *old_tsec = selinux_cred(old);
3887 struct task_security_struct *tsec = selinux_cred(new);
3888
3889 *tsec = *old_tsec;
3890 return 0;
3891}
3892
3893/*
3894 * transfer the SELinux data to a blank set of creds
3895 */
3896static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3897{
3898 const struct task_security_struct *old_tsec = selinux_cred(old);
3899 struct task_security_struct *tsec = selinux_cred(new);
3900
3901 *tsec = *old_tsec;
3902}
3903
3904static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3905{
3906 *secid = cred_sid(c);
3907}
3908
3909/*
3910 * set the security data for a kernel service
3911 * - all the creation contexts are set to unlabelled
3912 */
3913static int selinux_kernel_act_as(struct cred *new, u32 secid)
3914{
3915 struct task_security_struct *tsec = selinux_cred(new);
3916 u32 sid = current_sid();
3917 int ret;
3918
3919 ret = avc_has_perm(&selinux_state,
3920 sid, secid,
3921 SECCLASS_KERNEL_SERVICE,
3922 KERNEL_SERVICE__USE_AS_OVERRIDE,
3923 NULL);
3924 if (ret == 0) {
3925 tsec->sid = secid;
3926 tsec->create_sid = 0;
3927 tsec->keycreate_sid = 0;
3928 tsec->sockcreate_sid = 0;
3929 }
3930 return ret;
3931}
3932
3933/*
3934 * set the file creation context in a security record to the same as the
3935 * objective context of the specified inode
3936 */
3937static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3938{
3939 struct inode_security_struct *isec = inode_security(inode);
3940 struct task_security_struct *tsec = selinux_cred(new);
3941 u32 sid = current_sid();
3942 int ret;
3943
3944 ret = avc_has_perm(&selinux_state,
3945 sid, isec->sid,
3946 SECCLASS_KERNEL_SERVICE,
3947 KERNEL_SERVICE__CREATE_FILES_AS,
3948 NULL);
3949
3950 if (ret == 0)
3951 tsec->create_sid = isec->sid;
3952 return ret;
3953}
3954
3955static int selinux_kernel_module_request(char *kmod_name)
3956{
3957 struct common_audit_data ad;
3958
3959 ad.type = LSM_AUDIT_DATA_KMOD;
3960 ad.u.kmod_name = kmod_name;
3961
3962 return avc_has_perm(&selinux_state,
3963 current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
3964 SYSTEM__MODULE_REQUEST, &ad);
3965}
3966
3967static int selinux_kernel_module_from_file(struct file *file)
3968{
3969 struct common_audit_data ad;
3970 struct inode_security_struct *isec;
3971 struct file_security_struct *fsec;
3972 u32 sid = current_sid();
3973 int rc;
3974
3975 /* init_module */
3976 if (file == NULL)
3977 return avc_has_perm(&selinux_state,
3978 sid, sid, SECCLASS_SYSTEM,
3979 SYSTEM__MODULE_LOAD, NULL);
3980
3981 /* finit_module */
3982
3983 ad.type = LSM_AUDIT_DATA_FILE;
3984 ad.u.file = file;
3985
3986 fsec = selinux_file(file);
3987 if (sid != fsec->sid) {
3988 rc = avc_has_perm(&selinux_state,
3989 sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
3990 if (rc)
3991 return rc;
3992 }
3993
3994 isec = inode_security(file_inode(file));
3995 return avc_has_perm(&selinux_state,
3996 sid, isec->sid, SECCLASS_SYSTEM,
3997 SYSTEM__MODULE_LOAD, &ad);
3998}
3999
4000static int selinux_kernel_read_file(struct file *file,
4001 enum kernel_read_file_id id)
4002{
4003 int rc = 0;
4004
4005 switch (id) {
4006 case READING_MODULE:
4007 rc = selinux_kernel_module_from_file(file);
4008 break;
4009 default:
4010 break;
4011 }
4012
4013 return rc;
4014}
4015
4016static int selinux_kernel_load_data(enum kernel_load_data_id id)
4017{
4018 int rc = 0;
4019
4020 switch (id) {
4021 case LOADING_MODULE:
4022 rc = selinux_kernel_module_from_file(NULL);
4023 default:
4024 break;
4025 }
4026
4027 return rc;
4028}
4029
4030static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4031{
4032 return avc_has_perm(&selinux_state,
4033 current_sid(), task_sid(p), SECCLASS_PROCESS,
4034 PROCESS__SETPGID, NULL);
4035}
4036
4037static int selinux_task_getpgid(struct task_struct *p)
4038{
4039 return avc_has_perm(&selinux_state,
4040 current_sid(), task_sid(p), SECCLASS_PROCESS,
4041 PROCESS__GETPGID, NULL);
4042}
4043
4044static int selinux_task_getsid(struct task_struct *p)
4045{
4046 return avc_has_perm(&selinux_state,
4047 current_sid(), task_sid(p), SECCLASS_PROCESS,
4048 PROCESS__GETSESSION, NULL);
4049}
4050
4051static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
4052{
4053 *secid = task_sid(p);
4054}
4055
4056static int selinux_task_setnice(struct task_struct *p, int nice)
4057{
4058 return avc_has_perm(&selinux_state,
4059 current_sid(), task_sid(p), SECCLASS_PROCESS,
4060 PROCESS__SETSCHED, NULL);
4061}
4062
4063static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4064{
4065 return avc_has_perm(&selinux_state,
4066 current_sid(), task_sid(p), SECCLASS_PROCESS,
4067 PROCESS__SETSCHED, NULL);
4068}
4069
4070static int selinux_task_getioprio(struct task_struct *p)
4071{
4072 return avc_has_perm(&selinux_state,
4073 current_sid(), task_sid(p), SECCLASS_PROCESS,
4074 PROCESS__GETSCHED, NULL);
4075}
4076
4077static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4078 unsigned int flags)
4079{
4080 u32 av = 0;
4081
4082 if (!flags)
4083 return 0;
4084 if (flags & LSM_PRLIMIT_WRITE)
4085 av |= PROCESS__SETRLIMIT;
4086 if (flags & LSM_PRLIMIT_READ)
4087 av |= PROCESS__GETRLIMIT;
4088 return avc_has_perm(&selinux_state,
4089 cred_sid(cred), cred_sid(tcred),
4090 SECCLASS_PROCESS, av, NULL);
4091}
4092
4093static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4094 struct rlimit *new_rlim)
4095{
4096 struct rlimit *old_rlim = p->signal->rlim + resource;
4097
4098 /* Control the ability to change the hard limit (whether
4099 lowering or raising it), so that the hard limit can
4100 later be used as a safe reset point for the soft limit
4101 upon context transitions. See selinux_bprm_committing_creds. */
4102 if (old_rlim->rlim_max != new_rlim->rlim_max)
4103 return avc_has_perm(&selinux_state,
4104 current_sid(), task_sid(p),
4105 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4106
4107 return 0;
4108}
4109
4110static int selinux_task_setscheduler(struct task_struct *p)
4111{
4112 return avc_has_perm(&selinux_state,
4113 current_sid(), task_sid(p), SECCLASS_PROCESS,
4114 PROCESS__SETSCHED, NULL);
4115}
4116
4117static int selinux_task_getscheduler(struct task_struct *p)
4118{
4119 return avc_has_perm(&selinux_state,
4120 current_sid(), task_sid(p), SECCLASS_PROCESS,
4121 PROCESS__GETSCHED, NULL);
4122}
4123
4124static int selinux_task_movememory(struct task_struct *p)
4125{
4126 return avc_has_perm(&selinux_state,
4127 current_sid(), task_sid(p), SECCLASS_PROCESS,
4128 PROCESS__SETSCHED, NULL);
4129}
4130
4131static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4132 int sig, const struct cred *cred)
4133{
4134 u32 secid;
4135 u32 perm;
4136
4137 if (!sig)
4138 perm = PROCESS__SIGNULL; /* null signal; existence test */
4139 else
4140 perm = signal_to_av(sig);
4141 if (!cred)
4142 secid = current_sid();
4143 else
4144 secid = cred_sid(cred);
4145 return avc_has_perm(&selinux_state,
4146 secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
4147}
4148
4149static void selinux_task_to_inode(struct task_struct *p,
4150 struct inode *inode)
4151{
4152 struct inode_security_struct *isec = selinux_inode(inode);
4153 u32 sid = task_sid(p);
4154
4155 spin_lock(&isec->lock);
4156 isec->sclass = inode_mode_to_security_class(inode->i_mode);
4157 isec->sid = sid;
4158 isec->initialized = LABEL_INITIALIZED;
4159 spin_unlock(&isec->lock);
4160}
4161
4162/* Returns error only if unable to parse addresses */
4163static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4164 struct common_audit_data *ad, u8 *proto)
4165{
4166 int offset, ihlen, ret = -EINVAL;
4167 struct iphdr _iph, *ih;
4168
4169 offset = skb_network_offset(skb);
4170 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4171 if (ih == NULL)
4172 goto out;
4173
4174 ihlen = ih->ihl * 4;
4175 if (ihlen < sizeof(_iph))
4176 goto out;
4177
4178 ad->u.net->v4info.saddr = ih->saddr;
4179 ad->u.net->v4info.daddr = ih->daddr;
4180 ret = 0;
4181
4182 if (proto)
4183 *proto = ih->protocol;
4184
4185 switch (ih->protocol) {
4186 case IPPROTO_TCP: {
4187 struct tcphdr _tcph, *th;
4188
4189 if (ntohs(ih->frag_off) & IP_OFFSET)
4190 break;
4191
4192 offset += ihlen;
4193 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4194 if (th == NULL)
4195 break;
4196
4197 ad->u.net->sport = th->source;
4198 ad->u.net->dport = th->dest;
4199 break;
4200 }
4201
4202 case IPPROTO_UDP: {
4203 struct udphdr _udph, *uh;
4204
4205 if (ntohs(ih->frag_off) & IP_OFFSET)
4206 break;
4207
4208 offset += ihlen;
4209 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4210 if (uh == NULL)
4211 break;
4212
4213 ad->u.net->sport = uh->source;
4214 ad->u.net->dport = uh->dest;
4215 break;
4216 }
4217
4218 case IPPROTO_DCCP: {
4219 struct dccp_hdr _dccph, *dh;
4220
4221 if (ntohs(ih->frag_off) & IP_OFFSET)
4222 break;
4223
4224 offset += ihlen;
4225 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4226 if (dh == NULL)
4227 break;
4228
4229 ad->u.net->sport = dh->dccph_sport;
4230 ad->u.net->dport = dh->dccph_dport;
4231 break;
4232 }
4233
4234#if IS_ENABLED(CONFIG_IP_SCTP)
4235 case IPPROTO_SCTP: {
4236 struct sctphdr _sctph, *sh;
4237
4238 if (ntohs(ih->frag_off) & IP_OFFSET)
4239 break;
4240
4241 offset += ihlen;
4242 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4243 if (sh == NULL)
4244 break;
4245
4246 ad->u.net->sport = sh->source;
4247 ad->u.net->dport = sh->dest;
4248 break;
4249 }
4250#endif
4251 default:
4252 break;
4253 }
4254out:
4255 return ret;
4256}
4257
4258#if IS_ENABLED(CONFIG_IPV6)
4259
4260/* Returns error only if unable to parse addresses */
4261static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4262 struct common_audit_data *ad, u8 *proto)
4263{
4264 u8 nexthdr;
4265 int ret = -EINVAL, offset;
4266 struct ipv6hdr _ipv6h, *ip6;
4267 __be16 frag_off;
4268
4269 offset = skb_network_offset(skb);
4270 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4271 if (ip6 == NULL)
4272 goto out;
4273
4274 ad->u.net->v6info.saddr = ip6->saddr;
4275 ad->u.net->v6info.daddr = ip6->daddr;
4276 ret = 0;
4277
4278 nexthdr = ip6->nexthdr;
4279 offset += sizeof(_ipv6h);
4280 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4281 if (offset < 0)
4282 goto out;
4283
4284 if (proto)
4285 *proto = nexthdr;
4286
4287 switch (nexthdr) {
4288 case IPPROTO_TCP: {
4289 struct tcphdr _tcph, *th;
4290
4291 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4292 if (th == NULL)
4293 break;
4294
4295 ad->u.net->sport = th->source;
4296 ad->u.net->dport = th->dest;
4297 break;
4298 }
4299
4300 case IPPROTO_UDP: {
4301 struct udphdr _udph, *uh;
4302
4303 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4304 if (uh == NULL)
4305 break;
4306
4307 ad->u.net->sport = uh->source;
4308 ad->u.net->dport = uh->dest;
4309 break;
4310 }
4311
4312 case IPPROTO_DCCP: {
4313 struct dccp_hdr _dccph, *dh;
4314
4315 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4316 if (dh == NULL)
4317 break;
4318
4319 ad->u.net->sport = dh->dccph_sport;
4320 ad->u.net->dport = dh->dccph_dport;
4321 break;
4322 }
4323
4324#if IS_ENABLED(CONFIG_IP_SCTP)
4325 case IPPROTO_SCTP: {
4326 struct sctphdr _sctph, *sh;
4327
4328 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4329 if (sh == NULL)
4330 break;
4331
4332 ad->u.net->sport = sh->source;
4333 ad->u.net->dport = sh->dest;
4334 break;
4335 }
4336#endif
4337 /* includes fragments */
4338 default:
4339 break;
4340 }
4341out:
4342 return ret;
4343}
4344
4345#endif /* IPV6 */
4346
4347static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4348 char **_addrp, int src, u8 *proto)
4349{
4350 char *addrp;
4351 int ret;
4352
4353 switch (ad->u.net->family) {
4354 case PF_INET:
4355 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4356 if (ret)
4357 goto parse_error;
4358 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4359 &ad->u.net->v4info.daddr);
4360 goto okay;
4361
4362#if IS_ENABLED(CONFIG_IPV6)
4363 case PF_INET6:
4364 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4365 if (ret)
4366 goto parse_error;
4367 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4368 &ad->u.net->v6info.daddr);
4369 goto okay;
4370#endif /* IPV6 */
4371 default:
4372 addrp = NULL;
4373 goto okay;
4374 }
4375
4376parse_error:
4377 pr_warn(
4378 "SELinux: failure in selinux_parse_skb(),"
4379 " unable to parse packet\n");
4380 return ret;
4381
4382okay:
4383 if (_addrp)
4384 *_addrp = addrp;
4385 return 0;
4386}
4387
4388/**
4389 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4390 * @skb: the packet
4391 * @family: protocol family
4392 * @sid: the packet's peer label SID
4393 *
4394 * Description:
4395 * Check the various different forms of network peer labeling and determine
4396 * the peer label/SID for the packet; most of the magic actually occurs in
4397 * the security server function security_net_peersid_cmp(). The function
4398 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4399 * or -EACCES if @sid is invalid due to inconsistencies with the different
4400 * peer labels.
4401 *
4402 */
4403static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4404{
4405 int err;
4406 u32 xfrm_sid;
4407 u32 nlbl_sid;
4408 u32 nlbl_type;
4409
4410 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4411 if (unlikely(err))
4412 return -EACCES;
4413 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4414 if (unlikely(err))
4415 return -EACCES;
4416
4417 err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4418 nlbl_type, xfrm_sid, sid);
4419 if (unlikely(err)) {
4420 pr_warn(
4421 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4422 " unable to determine packet's peer label\n");
4423 return -EACCES;
4424 }
4425
4426 return 0;
4427}
4428
4429/**
4430 * selinux_conn_sid - Determine the child socket label for a connection
4431 * @sk_sid: the parent socket's SID
4432 * @skb_sid: the packet's SID
4433 * @conn_sid: the resulting connection SID
4434 *
4435 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4436 * combined with the MLS information from @skb_sid in order to create
4437 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy
4438 * of @sk_sid. Returns zero on success, negative values on failure.
4439 *
4440 */
4441static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4442{
4443 int err = 0;
4444
4445 if (skb_sid != SECSID_NULL)
4446 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4447 conn_sid);
4448 else
4449 *conn_sid = sk_sid;
4450
4451 return err;
4452}
4453
4454/* socket security operations */
4455
4456static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4457 u16 secclass, u32 *socksid)
4458{
4459 if (tsec->sockcreate_sid > SECSID_NULL) {
4460 *socksid = tsec->sockcreate_sid;
4461 return 0;
4462 }
4463
4464 return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4465 secclass, NULL, socksid);
4466}
4467
4468static int sock_has_perm(struct sock *sk, u32 perms)
4469{
4470 struct sk_security_struct *sksec = sk->sk_security;
4471 struct common_audit_data ad;
4472 struct lsm_network_audit net = {0,};
4473
4474 if (sksec->sid == SECINITSID_KERNEL)
4475 return 0;
4476
4477 ad.type = LSM_AUDIT_DATA_NET;
4478 ad.u.net = &net;
4479 ad.u.net->sk = sk;
4480
4481 return avc_has_perm(&selinux_state,
4482 current_sid(), sksec->sid, sksec->sclass, perms,
4483 &ad);
4484}
4485
4486static int selinux_socket_create(int family, int type,
4487 int protocol, int kern)
4488{
4489 const struct task_security_struct *tsec = selinux_cred(current_cred());
4490 u32 newsid;
4491 u16 secclass;
4492 int rc;
4493
4494 if (kern)
4495 return 0;
4496
4497 secclass = socket_type_to_security_class(family, type, protocol);
4498 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4499 if (rc)
4500 return rc;
4501
4502 return avc_has_perm(&selinux_state,
4503 tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4504}
4505
4506static int selinux_socket_post_create(struct socket *sock, int family,
4507 int type, int protocol, int kern)
4508{
4509 const struct task_security_struct *tsec = selinux_cred(current_cred());
4510 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4511 struct sk_security_struct *sksec;
4512 u16 sclass = socket_type_to_security_class(family, type, protocol);
4513 u32 sid = SECINITSID_KERNEL;
4514 int err = 0;
4515
4516 if (!kern) {
4517 err = socket_sockcreate_sid(tsec, sclass, &sid);
4518 if (err)
4519 return err;
4520 }
4521
4522 isec->sclass = sclass;
4523 isec->sid = sid;
4524 isec->initialized = LABEL_INITIALIZED;
4525
4526 if (sock->sk) {
4527 sksec = sock->sk->sk_security;
4528 sksec->sclass = sclass;
4529 sksec->sid = sid;
4530 /* Allows detection of the first association on this socket */
4531 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4532 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4533
4534 err = selinux_netlbl_socket_post_create(sock->sk, family);
4535 }
4536
4537 return err;
4538}
4539
4540static int selinux_socket_socketpair(struct socket *socka,
4541 struct socket *sockb)
4542{
4543 struct sk_security_struct *sksec_a = socka->sk->sk_security;
4544 struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4545
4546 sksec_a->peer_sid = sksec_b->sid;
4547 sksec_b->peer_sid = sksec_a->sid;
4548
4549 return 0;
4550}
4551
4552/* Range of port numbers used to automatically bind.
4553 Need to determine whether we should perform a name_bind
4554 permission check between the socket and the port number. */
4555
4556static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4557{
4558 struct sock *sk = sock->sk;
4559 struct sk_security_struct *sksec = sk->sk_security;
4560 u16 family;
4561 int err;
4562
4563 err = sock_has_perm(sk, SOCKET__BIND);
4564 if (err)
4565 goto out;
4566
4567 /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4568 family = sk->sk_family;
4569 if (family == PF_INET || family == PF_INET6) {
4570 char *addrp;
4571 struct common_audit_data ad;
4572 struct lsm_network_audit net = {0,};
4573 struct sockaddr_in *addr4 = NULL;
4574 struct sockaddr_in6 *addr6 = NULL;
4575 u16 family_sa;
4576 unsigned short snum;
4577 u32 sid, node_perm;
4578
4579 /*
4580 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4581 * that validates multiple binding addresses. Because of this
4582 * need to check address->sa_family as it is possible to have
4583 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4584 */
4585 if (addrlen < offsetofend(struct sockaddr, sa_family))
4586 return -EINVAL;
4587 family_sa = address->sa_family;
4588 switch (family_sa) {
4589 case AF_UNSPEC:
4590 case AF_INET:
4591 if (addrlen < sizeof(struct sockaddr_in))
4592 return -EINVAL;
4593 addr4 = (struct sockaddr_in *)address;
4594 if (family_sa == AF_UNSPEC) {
4595 /* see __inet_bind(), we only want to allow
4596 * AF_UNSPEC if the address is INADDR_ANY
4597 */
4598 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4599 goto err_af;
4600 family_sa = AF_INET;
4601 }
4602 snum = ntohs(addr4->sin_port);
4603 addrp = (char *)&addr4->sin_addr.s_addr;
4604 break;
4605 case AF_INET6:
4606 if (addrlen < SIN6_LEN_RFC2133)
4607 return -EINVAL;
4608 addr6 = (struct sockaddr_in6 *)address;
4609 snum = ntohs(addr6->sin6_port);
4610 addrp = (char *)&addr6->sin6_addr.s6_addr;
4611 break;
4612 default:
4613 goto err_af;
4614 }
4615
4616 ad.type = LSM_AUDIT_DATA_NET;
4617 ad.u.net = &net;
4618 ad.u.net->sport = htons(snum);
4619 ad.u.net->family = family_sa;
4620
4621 if (snum) {
4622 int low, high;
4623
4624 inet_get_local_port_range(sock_net(sk), &low, &high);
4625
4626 if (snum < max(inet_prot_sock(sock_net(sk)), low) ||
4627 snum > high) {
4628 err = sel_netport_sid(sk->sk_protocol,
4629 snum, &sid);
4630 if (err)
4631 goto out;
4632 err = avc_has_perm(&selinux_state,
4633 sksec->sid, sid,
4634 sksec->sclass,
4635 SOCKET__NAME_BIND, &ad);
4636 if (err)
4637 goto out;
4638 }
4639 }
4640
4641 switch (sksec->sclass) {
4642 case SECCLASS_TCP_SOCKET:
4643 node_perm = TCP_SOCKET__NODE_BIND;
4644 break;
4645
4646 case SECCLASS_UDP_SOCKET:
4647 node_perm = UDP_SOCKET__NODE_BIND;
4648 break;
4649
4650 case SECCLASS_DCCP_SOCKET:
4651 node_perm = DCCP_SOCKET__NODE_BIND;
4652 break;
4653
4654 case SECCLASS_SCTP_SOCKET:
4655 node_perm = SCTP_SOCKET__NODE_BIND;
4656 break;
4657
4658 default:
4659 node_perm = RAWIP_SOCKET__NODE_BIND;
4660 break;
4661 }
4662
4663 err = sel_netnode_sid(addrp, family_sa, &sid);
4664 if (err)
4665 goto out;
4666
4667 if (family_sa == AF_INET)
4668 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4669 else
4670 ad.u.net->v6info.saddr = addr6->sin6_addr;
4671
4672 err = avc_has_perm(&selinux_state,
4673 sksec->sid, sid,
4674 sksec->sclass, node_perm, &ad);
4675 if (err)
4676 goto out;
4677 }
4678out:
4679 return err;
4680err_af:
4681 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4682 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4683 return -EINVAL;
4684 return -EAFNOSUPPORT;
4685}
4686
4687/* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4688 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4689 */
4690static int selinux_socket_connect_helper(struct socket *sock,
4691 struct sockaddr *address, int addrlen)
4692{
4693 struct sock *sk = sock->sk;
4694 struct sk_security_struct *sksec = sk->sk_security;
4695 int err;
4696
4697 err = sock_has_perm(sk, SOCKET__CONNECT);
4698 if (err)
4699 return err;
4700 if (addrlen < offsetofend(struct sockaddr, sa_family))
4701 return -EINVAL;
4702
4703 /* connect(AF_UNSPEC) has special handling, as it is a documented
4704 * way to disconnect the socket
4705 */
4706 if (address->sa_family == AF_UNSPEC)
4707 return 0;
4708
4709 /*
4710 * If a TCP, DCCP or SCTP socket, check name_connect permission
4711 * for the port.
4712 */
4713 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4714 sksec->sclass == SECCLASS_DCCP_SOCKET ||
4715 sksec->sclass == SECCLASS_SCTP_SOCKET) {
4716 struct common_audit_data ad;
4717 struct lsm_network_audit net = {0,};
4718 struct sockaddr_in *addr4 = NULL;
4719 struct sockaddr_in6 *addr6 = NULL;
4720 unsigned short snum;
4721 u32 sid, perm;
4722
4723 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4724 * that validates multiple connect addresses. Because of this
4725 * need to check address->sa_family as it is possible to have
4726 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4727 */
4728 switch (address->sa_family) {
4729 case AF_INET:
4730 addr4 = (struct sockaddr_in *)address;
4731 if (addrlen < sizeof(struct sockaddr_in))
4732 return -EINVAL;
4733 snum = ntohs(addr4->sin_port);
4734 break;
4735 case AF_INET6:
4736 addr6 = (struct sockaddr_in6 *)address;
4737 if (addrlen < SIN6_LEN_RFC2133)
4738 return -EINVAL;
4739 snum = ntohs(addr6->sin6_port);
4740 break;
4741 default:
4742 /* Note that SCTP services expect -EINVAL, whereas
4743 * others expect -EAFNOSUPPORT.
4744 */
4745 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4746 return -EINVAL;
4747 else
4748 return -EAFNOSUPPORT;
4749 }
4750
4751 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4752 if (err)
4753 return err;
4754
4755 switch (sksec->sclass) {
4756 case SECCLASS_TCP_SOCKET:
4757 perm = TCP_SOCKET__NAME_CONNECT;
4758 break;
4759 case SECCLASS_DCCP_SOCKET:
4760 perm = DCCP_SOCKET__NAME_CONNECT;
4761 break;
4762 case SECCLASS_SCTP_SOCKET:
4763 perm = SCTP_SOCKET__NAME_CONNECT;
4764 break;
4765 }
4766
4767 ad.type = LSM_AUDIT_DATA_NET;
4768 ad.u.net = &net;
4769 ad.u.net->dport = htons(snum);
4770 ad.u.net->family = address->sa_family;
4771 err = avc_has_perm(&selinux_state,
4772 sksec->sid, sid, sksec->sclass, perm, &ad);
4773 if (err)
4774 return err;
4775 }
4776
4777 return 0;
4778}
4779
4780/* Supports connect(2), see comments in selinux_socket_connect_helper() */
4781static int selinux_socket_connect(struct socket *sock,
4782 struct sockaddr *address, int addrlen)
4783{
4784 int err;
4785 struct sock *sk = sock->sk;
4786
4787 err = selinux_socket_connect_helper(sock, address, addrlen);
4788 if (err)
4789 return err;
4790
4791 return selinux_netlbl_socket_connect(sk, address);
4792}
4793
4794static int selinux_socket_listen(struct socket *sock, int backlog)
4795{
4796 return sock_has_perm(sock->sk, SOCKET__LISTEN);
4797}
4798
4799static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4800{
4801 int err;
4802 struct inode_security_struct *isec;
4803 struct inode_security_struct *newisec;
4804 u16 sclass;
4805 u32 sid;
4806
4807 err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4808 if (err)
4809 return err;
4810
4811 isec = inode_security_novalidate(SOCK_INODE(sock));
4812 spin_lock(&isec->lock);
4813 sclass = isec->sclass;
4814 sid = isec->sid;
4815 spin_unlock(&isec->lock);
4816
4817 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4818 newisec->sclass = sclass;
4819 newisec->sid = sid;
4820 newisec->initialized = LABEL_INITIALIZED;
4821
4822 return 0;
4823}
4824
4825static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4826 int size)
4827{
4828 return sock_has_perm(sock->sk, SOCKET__WRITE);
4829}
4830
4831static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4832 int size, int flags)
4833{
4834 return sock_has_perm(sock->sk, SOCKET__READ);
4835}
4836
4837static int selinux_socket_getsockname(struct socket *sock)
4838{
4839 return sock_has_perm(sock->sk, SOCKET__GETATTR);
4840}
4841
4842static int selinux_socket_getpeername(struct socket *sock)
4843{
4844 return sock_has_perm(sock->sk, SOCKET__GETATTR);
4845}
4846
4847static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4848{
4849 int err;
4850
4851 err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4852 if (err)
4853 return err;
4854
4855 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4856}
4857
4858static int selinux_socket_getsockopt(struct socket *sock, int level,
4859 int optname)
4860{
4861 return sock_has_perm(sock->sk, SOCKET__GETOPT);
4862}
4863
4864static int selinux_socket_shutdown(struct socket *sock, int how)
4865{
4866 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4867}
4868
4869static int selinux_socket_unix_stream_connect(struct sock *sock,
4870 struct sock *other,
4871 struct sock *newsk)
4872{
4873 struct sk_security_struct *sksec_sock = sock->sk_security;
4874 struct sk_security_struct *sksec_other = other->sk_security;
4875 struct sk_security_struct *sksec_new = newsk->sk_security;
4876 struct common_audit_data ad;
4877 struct lsm_network_audit net = {0,};
4878 int err;
4879
4880 ad.type = LSM_AUDIT_DATA_NET;
4881 ad.u.net = &net;
4882 ad.u.net->sk = other;
4883
4884 err = avc_has_perm(&selinux_state,
4885 sksec_sock->sid, sksec_other->sid,
4886 sksec_other->sclass,
4887 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4888 if (err)
4889 return err;
4890
4891 /* server child socket */
4892 sksec_new->peer_sid = sksec_sock->sid;
4893 err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
4894 sksec_sock->sid, &sksec_new->sid);
4895 if (err)
4896 return err;
4897
4898 /* connecting socket */
4899 sksec_sock->peer_sid = sksec_new->sid;
4900
4901 return 0;
4902}
4903
4904static int selinux_socket_unix_may_send(struct socket *sock,
4905 struct socket *other)
4906{
4907 struct sk_security_struct *ssec = sock->sk->sk_security;
4908 struct sk_security_struct *osec = other->sk->sk_security;
4909 struct common_audit_data ad;
4910 struct lsm_network_audit net = {0,};
4911
4912 ad.type = LSM_AUDIT_DATA_NET;
4913 ad.u.net = &net;
4914 ad.u.net->sk = other->sk;
4915
4916 return avc_has_perm(&selinux_state,
4917 ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4918 &ad);
4919}
4920
4921static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4922 char *addrp, u16 family, u32 peer_sid,
4923 struct common_audit_data *ad)
4924{
4925 int err;
4926 u32 if_sid;
4927 u32 node_sid;
4928
4929 err = sel_netif_sid(ns, ifindex, &if_sid);
4930 if (err)
4931 return err;
4932 err = avc_has_perm(&selinux_state,
4933 peer_sid, if_sid,
4934 SECCLASS_NETIF, NETIF__INGRESS, ad);
4935 if (err)
4936 return err;
4937
4938 err = sel_netnode_sid(addrp, family, &node_sid);
4939 if (err)
4940 return err;
4941 return avc_has_perm(&selinux_state,
4942 peer_sid, node_sid,
4943 SECCLASS_NODE, NODE__RECVFROM, ad);
4944}
4945
4946static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4947 u16 family)
4948{
4949 int err = 0;
4950 struct sk_security_struct *sksec = sk->sk_security;
4951 u32 sk_sid = sksec->sid;
4952 struct common_audit_data ad;
4953 struct lsm_network_audit net = {0,};
4954 char *addrp;
4955
4956 ad.type = LSM_AUDIT_DATA_NET;
4957 ad.u.net = &net;
4958 ad.u.net->netif = skb->skb_iif;
4959 ad.u.net->family = family;
4960 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4961 if (err)
4962 return err;
4963
4964 if (selinux_secmark_enabled()) {
4965 err = avc_has_perm(&selinux_state,
4966 sk_sid, skb->secmark, SECCLASS_PACKET,
4967 PACKET__RECV, &ad);
4968 if (err)
4969 return err;
4970 }
4971
4972 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4973 if (err)
4974 return err;
4975 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4976
4977 return err;
4978}
4979
4980static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4981{
4982 int err;
4983 struct sk_security_struct *sksec = sk->sk_security;
4984 u16 family = sk->sk_family;
4985 u32 sk_sid = sksec->sid;
4986 struct common_audit_data ad;
4987 struct lsm_network_audit net = {0,};
4988 char *addrp;
4989 u8 secmark_active;
4990 u8 peerlbl_active;
4991
4992 if (family != PF_INET && family != PF_INET6)
4993 return 0;
4994
4995 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4996 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4997 family = PF_INET;
4998
4999 /* If any sort of compatibility mode is enabled then handoff processing
5000 * to the selinux_sock_rcv_skb_compat() function to deal with the
5001 * special handling. We do this in an attempt to keep this function
5002 * as fast and as clean as possible. */
5003 if (!selinux_policycap_netpeer())
5004 return selinux_sock_rcv_skb_compat(sk, skb, family);
5005
5006 secmark_active = selinux_secmark_enabled();
5007 peerlbl_active = selinux_peerlbl_enabled();
5008 if (!secmark_active && !peerlbl_active)
5009 return 0;
5010
5011 ad.type = LSM_AUDIT_DATA_NET;
5012 ad.u.net = &net;
5013 ad.u.net->netif = skb->skb_iif;
5014 ad.u.net->family = family;
5015 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5016 if (err)
5017 return err;
5018
5019 if (peerlbl_active) {
5020 u32 peer_sid;
5021
5022 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5023 if (err)
5024 return err;
5025 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5026 addrp, family, peer_sid, &ad);
5027 if (err) {
5028 selinux_netlbl_err(skb, family, err, 0);
5029 return err;
5030 }
5031 err = avc_has_perm(&selinux_state,
5032 sk_sid, peer_sid, SECCLASS_PEER,
5033 PEER__RECV, &ad);
5034 if (err) {
5035 selinux_netlbl_err(skb, family, err, 0);
5036 return err;
5037 }
5038 }
5039
5040 if (secmark_active) {
5041 err = avc_has_perm(&selinux_state,
5042 sk_sid, skb->secmark, SECCLASS_PACKET,
5043 PACKET__RECV, &ad);
5044 if (err)
5045 return err;
5046 }
5047
5048 return err;
5049}
5050
5051static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
5052 int __user *optlen, unsigned len)
5053{
5054 int err = 0;
5055 char *scontext;
5056 u32 scontext_len;
5057 struct sk_security_struct *sksec = sock->sk->sk_security;
5058 u32 peer_sid = SECSID_NULL;
5059
5060 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5061 sksec->sclass == SECCLASS_TCP_SOCKET ||
5062 sksec->sclass == SECCLASS_SCTP_SOCKET)
5063 peer_sid = sksec->peer_sid;
5064 if (peer_sid == SECSID_NULL)
5065 return -ENOPROTOOPT;
5066
5067 err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5068 &scontext_len);
5069 if (err)
5070 return err;
5071
5072 if (scontext_len > len) {
5073 err = -ERANGE;
5074 goto out_len;
5075 }
5076
5077 if (copy_to_user(optval, scontext, scontext_len))
5078 err = -EFAULT;
5079
5080out_len:
5081 if (put_user(scontext_len, optlen))
5082 err = -EFAULT;
5083 kfree(scontext);
5084 return err;
5085}
5086
5087static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5088{
5089 u32 peer_secid = SECSID_NULL;
5090 u16 family;
5091 struct inode_security_struct *isec;
5092
5093 if (skb && skb->protocol == htons(ETH_P_IP))
5094 family = PF_INET;
5095 else if (skb && skb->protocol == htons(ETH_P_IPV6))
5096 family = PF_INET6;
5097 else if (sock)
5098 family = sock->sk->sk_family;
5099 else
5100 goto out;
5101
5102 if (sock && family == PF_UNIX) {
5103 isec = inode_security_novalidate(SOCK_INODE(sock));
5104 peer_secid = isec->sid;
5105 } else if (skb)
5106 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5107
5108out:
5109 *secid = peer_secid;
5110 if (peer_secid == SECSID_NULL)
5111 return -EINVAL;
5112 return 0;
5113}
5114
5115static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5116{
5117 struct sk_security_struct *sksec;
5118
5119 sksec = kzalloc(sizeof(*sksec), priority);
5120 if (!sksec)
5121 return -ENOMEM;
5122
5123 sksec->peer_sid = SECINITSID_UNLABELED;
5124 sksec->sid = SECINITSID_UNLABELED;
5125 sksec->sclass = SECCLASS_SOCKET;
5126 selinux_netlbl_sk_security_reset(sksec);
5127 sk->sk_security = sksec;
5128
5129 return 0;
5130}
5131
5132static void selinux_sk_free_security(struct sock *sk)
5133{
5134 struct sk_security_struct *sksec = sk->sk_security;
5135
5136 sk->sk_security = NULL;
5137 selinux_netlbl_sk_security_free(sksec);
5138 kfree(sksec);
5139}
5140
5141static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5142{
5143 struct sk_security_struct *sksec = sk->sk_security;
5144 struct sk_security_struct *newsksec = newsk->sk_security;
5145
5146 newsksec->sid = sksec->sid;
5147 newsksec->peer_sid = sksec->peer_sid;
5148 newsksec->sclass = sksec->sclass;
5149
5150 selinux_netlbl_sk_security_reset(newsksec);
5151}
5152
5153static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5154{
5155 if (!sk)
5156 *secid = SECINITSID_ANY_SOCKET;
5157 else {
5158 struct sk_security_struct *sksec = sk->sk_security;
5159
5160 *secid = sksec->sid;
5161 }
5162}
5163
5164static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5165{
5166 struct inode_security_struct *isec =
5167 inode_security_novalidate(SOCK_INODE(parent));
5168 struct sk_security_struct *sksec = sk->sk_security;
5169
5170 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5171 sk->sk_family == PF_UNIX)
5172 isec->sid = sksec->sid;
5173 sksec->sclass = isec->sclass;
5174}
5175
5176/* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5177 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5178 * already present).
5179 */
5180static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5181 struct sk_buff *skb)
5182{
5183 struct sk_security_struct *sksec = ep->base.sk->sk_security;
5184 struct common_audit_data ad;
5185 struct lsm_network_audit net = {0,};
5186 u8 peerlbl_active;
5187 u32 peer_sid = SECINITSID_UNLABELED;
5188 u32 conn_sid;
5189 int err = 0;
5190
5191 if (!selinux_policycap_extsockclass())
5192 return 0;
5193
5194 peerlbl_active = selinux_peerlbl_enabled();
5195
5196 if (peerlbl_active) {
5197 /* This will return peer_sid = SECSID_NULL if there are
5198 * no peer labels, see security_net_peersid_resolve().
5199 */
5200 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5201 &peer_sid);
5202 if (err)
5203 return err;
5204
5205 if (peer_sid == SECSID_NULL)
5206 peer_sid = SECINITSID_UNLABELED;
5207 }
5208
5209 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5210 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5211
5212 /* Here as first association on socket. As the peer SID
5213 * was allowed by peer recv (and the netif/node checks),
5214 * then it is approved by policy and used as the primary
5215 * peer SID for getpeercon(3).
5216 */
5217 sksec->peer_sid = peer_sid;
5218 } else if (sksec->peer_sid != peer_sid) {
5219 /* Other association peer SIDs are checked to enforce
5220 * consistency among the peer SIDs.
5221 */
5222 ad.type = LSM_AUDIT_DATA_NET;
5223 ad.u.net = &net;
5224 ad.u.net->sk = ep->base.sk;
5225 err = avc_has_perm(&selinux_state,
5226 sksec->peer_sid, peer_sid, sksec->sclass,
5227 SCTP_SOCKET__ASSOCIATION, &ad);
5228 if (err)
5229 return err;
5230 }
5231
5232 /* Compute the MLS component for the connection and store
5233 * the information in ep. This will be used by SCTP TCP type
5234 * sockets and peeled off connections as they cause a new
5235 * socket to be generated. selinux_sctp_sk_clone() will then
5236 * plug this into the new socket.
5237 */
5238 err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5239 if (err)
5240 return err;
5241
5242 ep->secid = conn_sid;
5243 ep->peer_secid = peer_sid;
5244
5245 /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5246 return selinux_netlbl_sctp_assoc_request(ep, skb);
5247}
5248
5249/* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5250 * based on their @optname.
5251 */
5252static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5253 struct sockaddr *address,
5254 int addrlen)
5255{
5256 int len, err = 0, walk_size = 0;
5257 void *addr_buf;
5258 struct sockaddr *addr;
5259 struct socket *sock;
5260
5261 if (!selinux_policycap_extsockclass())
5262 return 0;
5263
5264 /* Process one or more addresses that may be IPv4 or IPv6 */
5265 sock = sk->sk_socket;
5266 addr_buf = address;
5267
5268 while (walk_size < addrlen) {
5269 if (walk_size + sizeof(sa_family_t) > addrlen)
5270 return -EINVAL;
5271
5272 addr = addr_buf;
5273 switch (addr->sa_family) {
5274 case AF_UNSPEC:
5275 case AF_INET:
5276 len = sizeof(struct sockaddr_in);
5277 break;
5278 case AF_INET6:
5279 len = sizeof(struct sockaddr_in6);
5280 break;
5281 default:
5282 return -EINVAL;
5283 }
5284
5285 if (walk_size + len > addrlen)
5286 return -EINVAL;
5287
5288 err = -EINVAL;
5289 switch (optname) {
5290 /* Bind checks */
5291 case SCTP_PRIMARY_ADDR:
5292 case SCTP_SET_PEER_PRIMARY_ADDR:
5293 case SCTP_SOCKOPT_BINDX_ADD:
5294 err = selinux_socket_bind(sock, addr, len);
5295 break;
5296 /* Connect checks */
5297 case SCTP_SOCKOPT_CONNECTX:
5298 case SCTP_PARAM_SET_PRIMARY:
5299 case SCTP_PARAM_ADD_IP:
5300 case SCTP_SENDMSG_CONNECT:
5301 err = selinux_socket_connect_helper(sock, addr, len);
5302 if (err)
5303 return err;
5304
5305 /* As selinux_sctp_bind_connect() is called by the
5306 * SCTP protocol layer, the socket is already locked,
5307 * therefore selinux_netlbl_socket_connect_locked() is
5308 * is called here. The situations handled are:
5309 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5310 * whenever a new IP address is added or when a new
5311 * primary address is selected.
5312 * Note that an SCTP connect(2) call happens before
5313 * the SCTP protocol layer and is handled via
5314 * selinux_socket_connect().
5315 */
5316 err = selinux_netlbl_socket_connect_locked(sk, addr);
5317 break;
5318 }
5319
5320 if (err)
5321 return err;
5322
5323 addr_buf += len;
5324 walk_size += len;
5325 }
5326
5327 return 0;
5328}
5329
5330/* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5331static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5332 struct sock *newsk)
5333{
5334 struct sk_security_struct *sksec = sk->sk_security;
5335 struct sk_security_struct *newsksec = newsk->sk_security;
5336
5337 /* If policy does not support SECCLASS_SCTP_SOCKET then call
5338 * the non-sctp clone version.
5339 */
5340 if (!selinux_policycap_extsockclass())
5341 return selinux_sk_clone_security(sk, newsk);
5342
5343 newsksec->sid = ep->secid;
5344 newsksec->peer_sid = ep->peer_secid;
5345 newsksec->sclass = sksec->sclass;
5346 selinux_netlbl_sctp_sk_clone(sk, newsk);
5347}
5348
5349static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
5350 struct request_sock *req)
5351{
5352 struct sk_security_struct *sksec = sk->sk_security;
5353 int err;
5354 u16 family = req->rsk_ops->family;
5355 u32 connsid;
5356 u32 peersid;
5357
5358 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5359 if (err)
5360 return err;
5361 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5362 if (err)
5363 return err;
5364 req->secid = connsid;
5365 req->peer_secid = peersid;
5366
5367 return selinux_netlbl_inet_conn_request(req, family);
5368}
5369
5370static void selinux_inet_csk_clone(struct sock *newsk,
5371 const struct request_sock *req)
5372{
5373 struct sk_security_struct *newsksec = newsk->sk_security;
5374
5375 newsksec->sid = req->secid;
5376 newsksec->peer_sid = req->peer_secid;
5377 /* NOTE: Ideally, we should also get the isec->sid for the
5378 new socket in sync, but we don't have the isec available yet.
5379 So we will wait until sock_graft to do it, by which
5380 time it will have been created and available. */
5381
5382 /* We don't need to take any sort of lock here as we are the only
5383 * thread with access to newsksec */
5384 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5385}
5386
5387static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5388{
5389 u16 family = sk->sk_family;
5390 struct sk_security_struct *sksec = sk->sk_security;
5391
5392 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5393 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5394 family = PF_INET;
5395
5396 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5397}
5398
5399static int selinux_secmark_relabel_packet(u32 sid)
5400{
5401 const struct task_security_struct *__tsec;
5402 u32 tsid;
5403
5404 __tsec = selinux_cred(current_cred());
5405 tsid = __tsec->sid;
5406
5407 return avc_has_perm(&selinux_state,
5408 tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5409 NULL);
5410}
5411
5412static void selinux_secmark_refcount_inc(void)
5413{
5414 atomic_inc(&selinux_secmark_refcount);
5415}
5416
5417static void selinux_secmark_refcount_dec(void)
5418{
5419 atomic_dec(&selinux_secmark_refcount);
5420}
5421
5422static void selinux_req_classify_flow(const struct request_sock *req,
5423 struct flowi *fl)
5424{
5425 fl->flowi_secid = req->secid;
5426}
5427
5428static int selinux_tun_dev_alloc_security(void **security)
5429{
5430 struct tun_security_struct *tunsec;
5431
5432 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5433 if (!tunsec)
5434 return -ENOMEM;
5435 tunsec->sid = current_sid();
5436
5437 *security = tunsec;
5438 return 0;
5439}
5440
5441static void selinux_tun_dev_free_security(void *security)
5442{
5443 kfree(security);
5444}
5445
5446static int selinux_tun_dev_create(void)
5447{
5448 u32 sid = current_sid();
5449
5450 /* we aren't taking into account the "sockcreate" SID since the socket
5451 * that is being created here is not a socket in the traditional sense,
5452 * instead it is a private sock, accessible only to the kernel, and
5453 * representing a wide range of network traffic spanning multiple
5454 * connections unlike traditional sockets - check the TUN driver to
5455 * get a better understanding of why this socket is special */
5456
5457 return avc_has_perm(&selinux_state,
5458 sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5459 NULL);
5460}
5461
5462static int selinux_tun_dev_attach_queue(void *security)
5463{
5464 struct tun_security_struct *tunsec = security;
5465
5466 return avc_has_perm(&selinux_state,
5467 current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5468 TUN_SOCKET__ATTACH_QUEUE, NULL);
5469}
5470
5471static int selinux_tun_dev_attach(struct sock *sk, void *security)
5472{
5473 struct tun_security_struct *tunsec = security;
5474 struct sk_security_struct *sksec = sk->sk_security;
5475
5476 /* we don't currently perform any NetLabel based labeling here and it
5477 * isn't clear that we would want to do so anyway; while we could apply
5478 * labeling without the support of the TUN user the resulting labeled
5479 * traffic from the other end of the connection would almost certainly
5480 * cause confusion to the TUN user that had no idea network labeling
5481 * protocols were being used */
5482
5483 sksec->sid = tunsec->sid;
5484 sksec->sclass = SECCLASS_TUN_SOCKET;
5485
5486 return 0;
5487}
5488
5489static int selinux_tun_dev_open(void *security)
5490{
5491 struct tun_security_struct *tunsec = security;
5492 u32 sid = current_sid();
5493 int err;
5494
5495 err = avc_has_perm(&selinux_state,
5496 sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5497 TUN_SOCKET__RELABELFROM, NULL);
5498 if (err)
5499 return err;
5500 err = avc_has_perm(&selinux_state,
5501 sid, sid, SECCLASS_TUN_SOCKET,
5502 TUN_SOCKET__RELABELTO, NULL);
5503 if (err)
5504 return err;
5505 tunsec->sid = sid;
5506
5507 return 0;
5508}
5509
5510static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
5511{
5512 int err = 0;
5513 u32 perm;
5514 struct nlmsghdr *nlh;
5515 struct sk_security_struct *sksec = sk->sk_security;
5516
5517 if (skb->len < NLMSG_HDRLEN) {
5518 err = -EINVAL;
5519 goto out;
5520 }
5521 nlh = nlmsg_hdr(skb);
5522
5523 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
5524 if (err) {
5525 if (err == -EINVAL) {
5526 pr_warn_ratelimited("SELinux: unrecognized netlink"
5527 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5528 " pig=%d comm=%s\n",
5529 sk->sk_protocol, nlh->nlmsg_type,
5530 secclass_map[sksec->sclass - 1].name,
5531 task_pid_nr(current), current->comm);
5532 if (!enforcing_enabled(&selinux_state) ||
5533 security_get_allow_unknown(&selinux_state))
5534 err = 0;
5535 }
5536
5537 /* Ignore */
5538 if (err == -ENOENT)
5539 err = 0;
5540 goto out;
5541 }
5542
5543 err = sock_has_perm(sk, perm);
5544out:
5545 return err;
5546}
5547
5548#ifdef CONFIG_NETFILTER
5549
5550static unsigned int selinux_ip_forward(struct sk_buff *skb,
5551 const struct net_device *indev,
5552 u16 family)
5553{
5554 int err;
5555 char *addrp;
5556 u32 peer_sid;
5557 struct common_audit_data ad;
5558 struct lsm_network_audit net = {0,};
5559 u8 secmark_active;
5560 u8 netlbl_active;
5561 u8 peerlbl_active;
5562
5563 if (!selinux_policycap_netpeer())
5564 return NF_ACCEPT;
5565
5566 secmark_active = selinux_secmark_enabled();
5567 netlbl_active = netlbl_enabled();
5568 peerlbl_active = selinux_peerlbl_enabled();
5569 if (!secmark_active && !peerlbl_active)
5570 return NF_ACCEPT;
5571
5572 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5573 return NF_DROP;
5574
5575 ad.type = LSM_AUDIT_DATA_NET;
5576 ad.u.net = &net;
5577 ad.u.net->netif = indev->ifindex;
5578 ad.u.net->family = family;
5579 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5580 return NF_DROP;
5581
5582 if (peerlbl_active) {
5583 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5584 addrp, family, peer_sid, &ad);
5585 if (err) {
5586 selinux_netlbl_err(skb, family, err, 1);
5587 return NF_DROP;
5588 }
5589 }
5590
5591 if (secmark_active)
5592 if (avc_has_perm(&selinux_state,
5593 peer_sid, skb->secmark,
5594 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5595 return NF_DROP;
5596
5597 if (netlbl_active)
5598 /* we do this in the FORWARD path and not the POST_ROUTING
5599 * path because we want to make sure we apply the necessary
5600 * labeling before IPsec is applied so we can leverage AH
5601 * protection */
5602 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5603 return NF_DROP;
5604
5605 return NF_ACCEPT;
5606}
5607
5608static unsigned int selinux_ipv4_forward(void *priv,
5609 struct sk_buff *skb,
5610 const struct nf_hook_state *state)
5611{
5612 return selinux_ip_forward(skb, state->in, PF_INET);
5613}
5614
5615#if IS_ENABLED(CONFIG_IPV6)
5616static unsigned int selinux_ipv6_forward(void *priv,
5617 struct sk_buff *skb,
5618 const struct nf_hook_state *state)
5619{
5620 return selinux_ip_forward(skb, state->in, PF_INET6);
5621}
5622#endif /* IPV6 */
5623
5624static unsigned int selinux_ip_output(struct sk_buff *skb,
5625 u16 family)
5626{
5627 struct sock *sk;
5628 u32 sid;
5629
5630 if (!netlbl_enabled())
5631 return NF_ACCEPT;
5632
5633 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5634 * because we want to make sure we apply the necessary labeling
5635 * before IPsec is applied so we can leverage AH protection */
5636 sk = skb->sk;
5637 if (sk) {
5638 struct sk_security_struct *sksec;
5639
5640 if (sk_listener(sk))
5641 /* if the socket is the listening state then this
5642 * packet is a SYN-ACK packet which means it needs to
5643 * be labeled based on the connection/request_sock and
5644 * not the parent socket. unfortunately, we can't
5645 * lookup the request_sock yet as it isn't queued on
5646 * the parent socket until after the SYN-ACK is sent.
5647 * the "solution" is to simply pass the packet as-is
5648 * as any IP option based labeling should be copied
5649 * from the initial connection request (in the IP
5650 * layer). it is far from ideal, but until we get a
5651 * security label in the packet itself this is the
5652 * best we can do. */
5653 return NF_ACCEPT;
5654
5655 /* standard practice, label using the parent socket */
5656 sksec = sk->sk_security;
5657 sid = sksec->sid;
5658 } else
5659 sid = SECINITSID_KERNEL;
5660 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5661 return NF_DROP;
5662
5663 return NF_ACCEPT;
5664}
5665
5666static unsigned int selinux_ipv4_output(void *priv,
5667 struct sk_buff *skb,
5668 const struct nf_hook_state *state)
5669{
5670 return selinux_ip_output(skb, PF_INET);
5671}
5672
5673#if IS_ENABLED(CONFIG_IPV6)
5674static unsigned int selinux_ipv6_output(void *priv,
5675 struct sk_buff *skb,
5676 const struct nf_hook_state *state)
5677{
5678 return selinux_ip_output(skb, PF_INET6);
5679}
5680#endif /* IPV6 */
5681
5682static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5683 int ifindex,
5684 u16 family)
5685{
5686 struct sock *sk = skb_to_full_sk(skb);
5687 struct sk_security_struct *sksec;
5688 struct common_audit_data ad;
5689 struct lsm_network_audit net = {0,};
5690 char *addrp;
5691 u8 proto;
5692
5693 if (sk == NULL)
5694 return NF_ACCEPT;
5695 sksec = sk->sk_security;
5696
5697 ad.type = LSM_AUDIT_DATA_NET;
5698 ad.u.net = &net;
5699 ad.u.net->netif = ifindex;
5700 ad.u.net->family = family;
5701 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5702 return NF_DROP;
5703
5704 if (selinux_secmark_enabled())
5705 if (avc_has_perm(&selinux_state,
5706 sksec->sid, skb->secmark,
5707 SECCLASS_PACKET, PACKET__SEND, &ad))
5708 return NF_DROP_ERR(-ECONNREFUSED);
5709
5710 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5711 return NF_DROP_ERR(-ECONNREFUSED);
5712
5713 return NF_ACCEPT;
5714}
5715
5716static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5717 const struct net_device *outdev,
5718 u16 family)
5719{
5720 u32 secmark_perm;
5721 u32 peer_sid;
5722 int ifindex = outdev->ifindex;
5723 struct sock *sk;
5724 struct common_audit_data ad;
5725 struct lsm_network_audit net = {0,};
5726 char *addrp;
5727 u8 secmark_active;
5728 u8 peerlbl_active;
5729
5730 /* If any sort of compatibility mode is enabled then handoff processing
5731 * to the selinux_ip_postroute_compat() function to deal with the
5732 * special handling. We do this in an attempt to keep this function
5733 * as fast and as clean as possible. */
5734 if (!selinux_policycap_netpeer())
5735 return selinux_ip_postroute_compat(skb, ifindex, family);
5736
5737 secmark_active = selinux_secmark_enabled();
5738 peerlbl_active = selinux_peerlbl_enabled();
5739 if (!secmark_active && !peerlbl_active)
5740 return NF_ACCEPT;
5741
5742 sk = skb_to_full_sk(skb);
5743
5744#ifdef CONFIG_XFRM
5745 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5746 * packet transformation so allow the packet to pass without any checks
5747 * since we'll have another chance to perform access control checks
5748 * when the packet is on it's final way out.
5749 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5750 * is NULL, in this case go ahead and apply access control.
5751 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5752 * TCP listening state we cannot wait until the XFRM processing
5753 * is done as we will miss out on the SA label if we do;
5754 * unfortunately, this means more work, but it is only once per
5755 * connection. */
5756 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5757 !(sk && sk_listener(sk)))
5758 return NF_ACCEPT;
5759#endif
5760
5761 if (sk == NULL) {
5762 /* Without an associated socket the packet is either coming
5763 * from the kernel or it is being forwarded; check the packet
5764 * to determine which and if the packet is being forwarded
5765 * query the packet directly to determine the security label. */
5766 if (skb->skb_iif) {
5767 secmark_perm = PACKET__FORWARD_OUT;
5768 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5769 return NF_DROP;
5770 } else {
5771 secmark_perm = PACKET__SEND;
5772 peer_sid = SECINITSID_KERNEL;
5773 }
5774 } else if (sk_listener(sk)) {
5775 /* Locally generated packet but the associated socket is in the
5776 * listening state which means this is a SYN-ACK packet. In
5777 * this particular case the correct security label is assigned
5778 * to the connection/request_sock but unfortunately we can't
5779 * query the request_sock as it isn't queued on the parent
5780 * socket until after the SYN-ACK packet is sent; the only
5781 * viable choice is to regenerate the label like we do in
5782 * selinux_inet_conn_request(). See also selinux_ip_output()
5783 * for similar problems. */
5784 u32 skb_sid;
5785 struct sk_security_struct *sksec;
5786
5787 sksec = sk->sk_security;
5788 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5789 return NF_DROP;
5790 /* At this point, if the returned skb peerlbl is SECSID_NULL
5791 * and the packet has been through at least one XFRM
5792 * transformation then we must be dealing with the "final"
5793 * form of labeled IPsec packet; since we've already applied
5794 * all of our access controls on this packet we can safely
5795 * pass the packet. */
5796 if (skb_sid == SECSID_NULL) {
5797 switch (family) {
5798 case PF_INET:
5799 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5800 return NF_ACCEPT;
5801 break;
5802 case PF_INET6:
5803 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5804 return NF_ACCEPT;
5805 break;
5806 default:
5807 return NF_DROP_ERR(-ECONNREFUSED);
5808 }
5809 }
5810 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5811 return NF_DROP;
5812 secmark_perm = PACKET__SEND;
5813 } else {
5814 /* Locally generated packet, fetch the security label from the
5815 * associated socket. */
5816 struct sk_security_struct *sksec = sk->sk_security;
5817 peer_sid = sksec->sid;
5818 secmark_perm = PACKET__SEND;
5819 }
5820
5821 ad.type = LSM_AUDIT_DATA_NET;
5822 ad.u.net = &net;
5823 ad.u.net->netif = ifindex;
5824 ad.u.net->family = family;
5825 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5826 return NF_DROP;
5827
5828 if (secmark_active)
5829 if (avc_has_perm(&selinux_state,
5830 peer_sid, skb->secmark,
5831 SECCLASS_PACKET, secmark_perm, &ad))
5832 return NF_DROP_ERR(-ECONNREFUSED);
5833
5834 if (peerlbl_active) {
5835 u32 if_sid;
5836 u32 node_sid;
5837
5838 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5839 return NF_DROP;
5840 if (avc_has_perm(&selinux_state,
5841 peer_sid, if_sid,
5842 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5843 return NF_DROP_ERR(-ECONNREFUSED);
5844
5845 if (sel_netnode_sid(addrp, family, &node_sid))
5846 return NF_DROP;
5847 if (avc_has_perm(&selinux_state,
5848 peer_sid, node_sid,
5849 SECCLASS_NODE, NODE__SENDTO, &ad))
5850 return NF_DROP_ERR(-ECONNREFUSED);
5851 }
5852
5853 return NF_ACCEPT;
5854}
5855
5856static unsigned int selinux_ipv4_postroute(void *priv,
5857 struct sk_buff *skb,
5858 const struct nf_hook_state *state)
5859{
5860 return selinux_ip_postroute(skb, state->out, PF_INET);
5861}
5862
5863#if IS_ENABLED(CONFIG_IPV6)
5864static unsigned int selinux_ipv6_postroute(void *priv,
5865 struct sk_buff *skb,
5866 const struct nf_hook_state *state)
5867{
5868 return selinux_ip_postroute(skb, state->out, PF_INET6);
5869}
5870#endif /* IPV6 */
5871
5872#endif /* CONFIG_NETFILTER */
5873
5874static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5875{
5876 return selinux_nlmsg_perm(sk, skb);
5877}
5878
5879static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5880{
5881 isec->sclass = sclass;
5882 isec->sid = current_sid();
5883}
5884
5885static int msg_msg_alloc_security(struct msg_msg *msg)
5886{
5887 struct msg_security_struct *msec;
5888
5889 msec = selinux_msg_msg(msg);
5890 msec->sid = SECINITSID_UNLABELED;
5891
5892 return 0;
5893}
5894
5895static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5896 u32 perms)
5897{
5898 struct ipc_security_struct *isec;
5899 struct common_audit_data ad;
5900 u32 sid = current_sid();
5901
5902 isec = selinux_ipc(ipc_perms);
5903
5904 ad.type = LSM_AUDIT_DATA_IPC;
5905 ad.u.ipc_id = ipc_perms->key;
5906
5907 return avc_has_perm(&selinux_state,
5908 sid, isec->sid, isec->sclass, perms, &ad);
5909}
5910
5911static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5912{
5913 return msg_msg_alloc_security(msg);
5914}
5915
5916/* message queue security operations */
5917static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5918{
5919 struct ipc_security_struct *isec;
5920 struct common_audit_data ad;
5921 u32 sid = current_sid();
5922 int rc;
5923
5924 isec = selinux_ipc(msq);
5925 ipc_init_security(isec, SECCLASS_MSGQ);
5926
5927 ad.type = LSM_AUDIT_DATA_IPC;
5928 ad.u.ipc_id = msq->key;
5929
5930 rc = avc_has_perm(&selinux_state,
5931 sid, isec->sid, SECCLASS_MSGQ,
5932 MSGQ__CREATE, &ad);
5933 return rc;
5934}
5935
5936static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
5937{
5938 struct ipc_security_struct *isec;
5939 struct common_audit_data ad;
5940 u32 sid = current_sid();
5941
5942 isec = selinux_ipc(msq);
5943
5944 ad.type = LSM_AUDIT_DATA_IPC;
5945 ad.u.ipc_id = msq->key;
5946
5947 return avc_has_perm(&selinux_state,
5948 sid, isec->sid, SECCLASS_MSGQ,
5949 MSGQ__ASSOCIATE, &ad);
5950}
5951
5952static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
5953{
5954 int err;
5955 int perms;
5956
5957 switch (cmd) {
5958 case IPC_INFO:
5959 case MSG_INFO:
5960 /* No specific object, just general system-wide information. */
5961 return avc_has_perm(&selinux_state,
5962 current_sid(), SECINITSID_KERNEL,
5963 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
5964 case IPC_STAT:
5965 case MSG_STAT:
5966 case MSG_STAT_ANY:
5967 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5968 break;
5969 case IPC_SET:
5970 perms = MSGQ__SETATTR;
5971 break;
5972 case IPC_RMID:
5973 perms = MSGQ__DESTROY;
5974 break;
5975 default:
5976 return 0;
5977 }
5978
5979 err = ipc_has_perm(msq, perms);
5980 return err;
5981}
5982
5983static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
5984{
5985 struct ipc_security_struct *isec;
5986 struct msg_security_struct *msec;
5987 struct common_audit_data ad;
5988 u32 sid = current_sid();
5989 int rc;
5990
5991 isec = selinux_ipc(msq);
5992 msec = selinux_msg_msg(msg);
5993
5994 /*
5995 * First time through, need to assign label to the message
5996 */
5997 if (msec->sid == SECINITSID_UNLABELED) {
5998 /*
5999 * Compute new sid based on current process and
6000 * message queue this message will be stored in
6001 */
6002 rc = security_transition_sid(&selinux_state, sid, isec->sid,
6003 SECCLASS_MSG, NULL, &msec->sid);
6004 if (rc)
6005 return rc;
6006 }
6007
6008 ad.type = LSM_AUDIT_DATA_IPC;
6009 ad.u.ipc_id = msq->key;
6010
6011 /* Can this process write to the queue? */
6012 rc = avc_has_perm(&selinux_state,
6013 sid, isec->sid, SECCLASS_MSGQ,
6014 MSGQ__WRITE, &ad);
6015 if (!rc)
6016 /* Can this process send the message */
6017 rc = avc_has_perm(&selinux_state,
6018 sid, msec->sid, SECCLASS_MSG,
6019 MSG__SEND, &ad);
6020 if (!rc)
6021 /* Can the message be put in the queue? */
6022 rc = avc_has_perm(&selinux_state,
6023 msec->sid, isec->sid, SECCLASS_MSGQ,
6024 MSGQ__ENQUEUE, &ad);
6025
6026 return rc;
6027}
6028
6029static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6030 struct task_struct *target,
6031 long type, int mode)
6032{
6033 struct ipc_security_struct *isec;
6034 struct msg_security_struct *msec;
6035 struct common_audit_data ad;
6036 u32 sid = task_sid(target);
6037 int rc;
6038
6039 isec = selinux_ipc(msq);
6040 msec = selinux_msg_msg(msg);
6041
6042 ad.type = LSM_AUDIT_DATA_IPC;
6043 ad.u.ipc_id = msq->key;
6044
6045 rc = avc_has_perm(&selinux_state,
6046 sid, isec->sid,
6047 SECCLASS_MSGQ, MSGQ__READ, &ad);
6048 if (!rc)
6049 rc = avc_has_perm(&selinux_state,
6050 sid, msec->sid,
6051 SECCLASS_MSG, MSG__RECEIVE, &ad);
6052 return rc;
6053}
6054
6055/* Shared Memory security operations */
6056static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6057{
6058 struct ipc_security_struct *isec;
6059 struct common_audit_data ad;
6060 u32 sid = current_sid();
6061 int rc;
6062
6063 isec = selinux_ipc(shp);
6064 ipc_init_security(isec, SECCLASS_SHM);
6065
6066 ad.type = LSM_AUDIT_DATA_IPC;
6067 ad.u.ipc_id = shp->key;
6068
6069 rc = avc_has_perm(&selinux_state,
6070 sid, isec->sid, SECCLASS_SHM,
6071 SHM__CREATE, &ad);
6072 return rc;
6073}
6074
6075static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6076{
6077 struct ipc_security_struct *isec;
6078 struct common_audit_data ad;
6079 u32 sid = current_sid();
6080
6081 isec = selinux_ipc(shp);
6082
6083 ad.type = LSM_AUDIT_DATA_IPC;
6084 ad.u.ipc_id = shp->key;
6085
6086 return avc_has_perm(&selinux_state,
6087 sid, isec->sid, SECCLASS_SHM,
6088 SHM__ASSOCIATE, &ad);
6089}
6090
6091/* Note, at this point, shp is locked down */
6092static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6093{
6094 int perms;
6095 int err;
6096
6097 switch (cmd) {
6098 case IPC_INFO:
6099 case SHM_INFO:
6100 /* No specific object, just general system-wide information. */
6101 return avc_has_perm(&selinux_state,
6102 current_sid(), SECINITSID_KERNEL,
6103 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6104 case IPC_STAT:
6105 case SHM_STAT:
6106 case SHM_STAT_ANY:
6107 perms = SHM__GETATTR | SHM__ASSOCIATE;
6108 break;
6109 case IPC_SET:
6110 perms = SHM__SETATTR;
6111 break;
6112 case SHM_LOCK:
6113 case SHM_UNLOCK:
6114 perms = SHM__LOCK;
6115 break;
6116 case IPC_RMID:
6117 perms = SHM__DESTROY;
6118 break;
6119 default:
6120 return 0;
6121 }
6122
6123 err = ipc_has_perm(shp, perms);
6124 return err;
6125}
6126
6127static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6128 char __user *shmaddr, int shmflg)
6129{
6130 u32 perms;
6131
6132 if (shmflg & SHM_RDONLY)
6133 perms = SHM__READ;
6134 else
6135 perms = SHM__READ | SHM__WRITE;
6136
6137 return ipc_has_perm(shp, perms);
6138}
6139
6140/* Semaphore security operations */
6141static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6142{
6143 struct ipc_security_struct *isec;
6144 struct common_audit_data ad;
6145 u32 sid = current_sid();
6146 int rc;
6147
6148 isec = selinux_ipc(sma);
6149 ipc_init_security(isec, SECCLASS_SEM);
6150
6151 ad.type = LSM_AUDIT_DATA_IPC;
6152 ad.u.ipc_id = sma->key;
6153
6154 rc = avc_has_perm(&selinux_state,
6155 sid, isec->sid, SECCLASS_SEM,
6156 SEM__CREATE, &ad);
6157 return rc;
6158}
6159
6160static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6161{
6162 struct ipc_security_struct *isec;
6163 struct common_audit_data ad;
6164 u32 sid = current_sid();
6165
6166 isec = selinux_ipc(sma);
6167
6168 ad.type = LSM_AUDIT_DATA_IPC;
6169 ad.u.ipc_id = sma->key;
6170
6171 return avc_has_perm(&selinux_state,
6172 sid, isec->sid, SECCLASS_SEM,
6173 SEM__ASSOCIATE, &ad);
6174}
6175
6176/* Note, at this point, sma is locked down */
6177static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6178{
6179 int err;
6180 u32 perms;
6181
6182 switch (cmd) {
6183 case IPC_INFO:
6184 case SEM_INFO:
6185 /* No specific object, just general system-wide information. */
6186 return avc_has_perm(&selinux_state,
6187 current_sid(), SECINITSID_KERNEL,
6188 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6189 case GETPID:
6190 case GETNCNT:
6191 case GETZCNT:
6192 perms = SEM__GETATTR;
6193 break;
6194 case GETVAL:
6195 case GETALL:
6196 perms = SEM__READ;
6197 break;
6198 case SETVAL:
6199 case SETALL:
6200 perms = SEM__WRITE;
6201 break;
6202 case IPC_RMID:
6203 perms = SEM__DESTROY;
6204 break;
6205 case IPC_SET:
6206 perms = SEM__SETATTR;
6207 break;
6208 case IPC_STAT:
6209 case SEM_STAT:
6210 case SEM_STAT_ANY:
6211 perms = SEM__GETATTR | SEM__ASSOCIATE;
6212 break;
6213 default:
6214 return 0;
6215 }
6216
6217 err = ipc_has_perm(sma, perms);
6218 return err;
6219}
6220
6221static int selinux_sem_semop(struct kern_ipc_perm *sma,
6222 struct sembuf *sops, unsigned nsops, int alter)
6223{
6224 u32 perms;
6225
6226 if (alter)
6227 perms = SEM__READ | SEM__WRITE;
6228 else
6229 perms = SEM__READ;
6230
6231 return ipc_has_perm(sma, perms);
6232}
6233
6234static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6235{
6236 u32 av = 0;
6237
6238 av = 0;
6239 if (flag & S_IRUGO)
6240 av |= IPC__UNIX_READ;
6241 if (flag & S_IWUGO)
6242 av |= IPC__UNIX_WRITE;
6243
6244 if (av == 0)
6245 return 0;
6246
6247 return ipc_has_perm(ipcp, av);
6248}
6249
6250static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6251{
6252 struct ipc_security_struct *isec = selinux_ipc(ipcp);
6253 *secid = isec->sid;
6254}
6255
6256static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6257{
6258 if (inode)
6259 inode_doinit_with_dentry(inode, dentry);
6260}
6261
6262static int selinux_getprocattr(struct task_struct *p,
6263 char *name, char **value)
6264{
6265 const struct task_security_struct *__tsec;
6266 u32 sid;
6267 int error;
6268 unsigned len;
6269
6270 rcu_read_lock();
6271 __tsec = selinux_cred(__task_cred(p));
6272
6273 if (current != p) {
6274 error = avc_has_perm(&selinux_state,
6275 current_sid(), __tsec->sid,
6276 SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6277 if (error)
6278 goto bad;
6279 }
6280
6281 if (!strcmp(name, "current"))
6282 sid = __tsec->sid;
6283 else if (!strcmp(name, "prev"))
6284 sid = __tsec->osid;
6285 else if (!strcmp(name, "exec"))
6286 sid = __tsec->exec_sid;
6287 else if (!strcmp(name, "fscreate"))
6288 sid = __tsec->create_sid;
6289 else if (!strcmp(name, "keycreate"))
6290 sid = __tsec->keycreate_sid;
6291 else if (!strcmp(name, "sockcreate"))
6292 sid = __tsec->sockcreate_sid;
6293 else {
6294 error = -EINVAL;
6295 goto bad;
6296 }
6297 rcu_read_unlock();
6298
6299 if (!sid)
6300 return 0;
6301
6302 error = security_sid_to_context(&selinux_state, sid, value, &len);
6303 if (error)
6304 return error;
6305 return len;
6306
6307bad:
6308 rcu_read_unlock();
6309 return error;
6310}
6311
6312static int selinux_setprocattr(const char *name, void *value, size_t size)
6313{
6314 struct task_security_struct *tsec;
6315 struct cred *new;
6316 u32 mysid = current_sid(), sid = 0, ptsid;
6317 int error;
6318 char *str = value;
6319
6320 /*
6321 * Basic control over ability to set these attributes at all.
6322 */
6323 if (!strcmp(name, "exec"))
6324 error = avc_has_perm(&selinux_state,
6325 mysid, mysid, SECCLASS_PROCESS,
6326 PROCESS__SETEXEC, NULL);
6327 else if (!strcmp(name, "fscreate"))
6328 error = avc_has_perm(&selinux_state,
6329 mysid, mysid, SECCLASS_PROCESS,
6330 PROCESS__SETFSCREATE, NULL);
6331 else if (!strcmp(name, "keycreate"))
6332 error = avc_has_perm(&selinux_state,
6333 mysid, mysid, SECCLASS_PROCESS,
6334 PROCESS__SETKEYCREATE, NULL);
6335 else if (!strcmp(name, "sockcreate"))
6336 error = avc_has_perm(&selinux_state,
6337 mysid, mysid, SECCLASS_PROCESS,
6338 PROCESS__SETSOCKCREATE, NULL);
6339 else if (!strcmp(name, "current"))
6340 error = avc_has_perm(&selinux_state,
6341 mysid, mysid, SECCLASS_PROCESS,
6342 PROCESS__SETCURRENT, NULL);
6343 else
6344 error = -EINVAL;
6345 if (error)
6346 return error;
6347
6348 /* Obtain a SID for the context, if one was specified. */
6349 if (size && str[0] && str[0] != '\n') {
6350 if (str[size-1] == '\n') {
6351 str[size-1] = 0;
6352 size--;
6353 }
6354 error = security_context_to_sid(&selinux_state, value, size,
6355 &sid, GFP_KERNEL);
6356 if (error == -EINVAL && !strcmp(name, "fscreate")) {
6357 if (!has_cap_mac_admin(true)) {
6358 struct audit_buffer *ab;
6359 size_t audit_size;
6360
6361 /* We strip a nul only if it is at the end, otherwise the
6362 * context contains a nul and we should audit that */
6363 if (str[size - 1] == '\0')
6364 audit_size = size - 1;
6365 else
6366 audit_size = size;
6367 ab = audit_log_start(audit_context(),
6368 GFP_ATOMIC,
6369 AUDIT_SELINUX_ERR);
6370 audit_log_format(ab, "op=fscreate invalid_context=");
6371 audit_log_n_untrustedstring(ab, value, audit_size);
6372 audit_log_end(ab);
6373
6374 return error;
6375 }
6376 error = security_context_to_sid_force(
6377 &selinux_state,
6378 value, size, &sid);
6379 }
6380 if (error)
6381 return error;
6382 }
6383
6384 new = prepare_creds();
6385 if (!new)
6386 return -ENOMEM;
6387
6388 /* Permission checking based on the specified context is
6389 performed during the actual operation (execve,
6390 open/mkdir/...), when we know the full context of the
6391 operation. See selinux_bprm_set_creds for the execve
6392 checks and may_create for the file creation checks. The
6393 operation will then fail if the context is not permitted. */
6394 tsec = selinux_cred(new);
6395 if (!strcmp(name, "exec")) {
6396 tsec->exec_sid = sid;
6397 } else if (!strcmp(name, "fscreate")) {
6398 tsec->create_sid = sid;
6399 } else if (!strcmp(name, "keycreate")) {
6400 if (sid) {
6401 error = avc_has_perm(&selinux_state, mysid, sid,
6402 SECCLASS_KEY, KEY__CREATE, NULL);
6403 if (error)
6404 goto abort_change;
6405 }
6406 tsec->keycreate_sid = sid;
6407 } else if (!strcmp(name, "sockcreate")) {
6408 tsec->sockcreate_sid = sid;
6409 } else if (!strcmp(name, "current")) {
6410 error = -EINVAL;
6411 if (sid == 0)
6412 goto abort_change;
6413
6414 /* Only allow single threaded processes to change context */
6415 error = -EPERM;
6416 if (!current_is_single_threaded()) {
6417 error = security_bounded_transition(&selinux_state,
6418 tsec->sid, sid);
6419 if (error)
6420 goto abort_change;
6421 }
6422
6423 /* Check permissions for the transition. */
6424 error = avc_has_perm(&selinux_state,
6425 tsec->sid, sid, SECCLASS_PROCESS,
6426 PROCESS__DYNTRANSITION, NULL);
6427 if (error)
6428 goto abort_change;
6429
6430 /* Check for ptracing, and update the task SID if ok.
6431 Otherwise, leave SID unchanged and fail. */
6432 ptsid = ptrace_parent_sid();
6433 if (ptsid != 0) {
6434 error = avc_has_perm(&selinux_state,
6435 ptsid, sid, SECCLASS_PROCESS,
6436 PROCESS__PTRACE, NULL);
6437 if (error)
6438 goto abort_change;
6439 }
6440
6441 tsec->sid = sid;
6442 } else {
6443 error = -EINVAL;
6444 goto abort_change;
6445 }
6446
6447 commit_creds(new);
6448 return size;
6449
6450abort_change:
6451 abort_creds(new);
6452 return error;
6453}
6454
6455static int selinux_ismaclabel(const char *name)
6456{
6457 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6458}
6459
6460static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6461{
6462 return security_sid_to_context(&selinux_state, secid,
6463 secdata, seclen);
6464}
6465
6466static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6467{
6468 return security_context_to_sid(&selinux_state, secdata, seclen,
6469 secid, GFP_KERNEL);
6470}
6471
6472static void selinux_release_secctx(char *secdata, u32 seclen)
6473{
6474 kfree(secdata);
6475}
6476
6477static void selinux_inode_invalidate_secctx(struct inode *inode)
6478{
6479 struct inode_security_struct *isec = selinux_inode(inode);
6480
6481 spin_lock(&isec->lock);
6482 isec->initialized = LABEL_INVALID;
6483 spin_unlock(&isec->lock);
6484}
6485
6486/*
6487 * called with inode->i_mutex locked
6488 */
6489static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6490{
6491 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6492 ctx, ctxlen, 0);
6493 /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6494 return rc == -EOPNOTSUPP ? 0 : rc;
6495}
6496
6497/*
6498 * called with inode->i_mutex locked
6499 */
6500static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6501{
6502 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6503}
6504
6505static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6506{
6507 int len = 0;
6508 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6509 ctx, true);
6510 if (len < 0)
6511 return len;
6512 *ctxlen = len;
6513 return 0;
6514}
6515#ifdef CONFIG_KEYS
6516
6517static int selinux_key_alloc(struct key *k, const struct cred *cred,
6518 unsigned long flags)
6519{
6520 const struct task_security_struct *tsec;
6521 struct key_security_struct *ksec;
6522
6523 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6524 if (!ksec)
6525 return -ENOMEM;
6526
6527 tsec = selinux_cred(cred);
6528 if (tsec->keycreate_sid)
6529 ksec->sid = tsec->keycreate_sid;
6530 else
6531 ksec->sid = tsec->sid;
6532
6533 k->security = ksec;
6534 return 0;
6535}
6536
6537static void selinux_key_free(struct key *k)
6538{
6539 struct key_security_struct *ksec = k->security;
6540
6541 k->security = NULL;
6542 kfree(ksec);
6543}
6544
6545static int selinux_key_permission(key_ref_t key_ref,
6546 const struct cred *cred,
6547 unsigned perm)
6548{
6549 struct key *key;
6550 struct key_security_struct *ksec;
6551 u32 sid;
6552
6553 /* if no specific permissions are requested, we skip the
6554 permission check. No serious, additional covert channels
6555 appear to be created. */
6556 if (perm == 0)
6557 return 0;
6558
6559 sid = cred_sid(cred);
6560
6561 key = key_ref_to_ptr(key_ref);
6562 ksec = key->security;
6563
6564 return avc_has_perm(&selinux_state,
6565 sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6566}
6567
6568static int selinux_key_getsecurity(struct key *key, char **_buffer)
6569{
6570 struct key_security_struct *ksec = key->security;
6571 char *context = NULL;
6572 unsigned len;
6573 int rc;
6574
6575 rc = security_sid_to_context(&selinux_state, ksec->sid,
6576 &context, &len);
6577 if (!rc)
6578 rc = len;
6579 *_buffer = context;
6580 return rc;
6581}
6582#endif
6583
6584#ifdef CONFIG_SECURITY_INFINIBAND
6585static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6586{
6587 struct common_audit_data ad;
6588 int err;
6589 u32 sid = 0;
6590 struct ib_security_struct *sec = ib_sec;
6591 struct lsm_ibpkey_audit ibpkey;
6592
6593 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6594 if (err)
6595 return err;
6596
6597 ad.type = LSM_AUDIT_DATA_IBPKEY;
6598 ibpkey.subnet_prefix = subnet_prefix;
6599 ibpkey.pkey = pkey_val;
6600 ad.u.ibpkey = &ibpkey;
6601 return avc_has_perm(&selinux_state,
6602 sec->sid, sid,
6603 SECCLASS_INFINIBAND_PKEY,
6604 INFINIBAND_PKEY__ACCESS, &ad);
6605}
6606
6607static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6608 u8 port_num)
6609{
6610 struct common_audit_data ad;
6611 int err;
6612 u32 sid = 0;
6613 struct ib_security_struct *sec = ib_sec;
6614 struct lsm_ibendport_audit ibendport;
6615
6616 err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6617 &sid);
6618
6619 if (err)
6620 return err;
6621
6622 ad.type = LSM_AUDIT_DATA_IBENDPORT;
6623 strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
6624 ibendport.port = port_num;
6625 ad.u.ibendport = &ibendport;
6626 return avc_has_perm(&selinux_state,
6627 sec->sid, sid,
6628 SECCLASS_INFINIBAND_ENDPORT,
6629 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6630}
6631
6632static int selinux_ib_alloc_security(void **ib_sec)
6633{
6634 struct ib_security_struct *sec;
6635
6636 sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6637 if (!sec)
6638 return -ENOMEM;
6639 sec->sid = current_sid();
6640
6641 *ib_sec = sec;
6642 return 0;
6643}
6644
6645static void selinux_ib_free_security(void *ib_sec)
6646{
6647 kfree(ib_sec);
6648}
6649#endif
6650
6651#ifdef CONFIG_BPF_SYSCALL
6652static int selinux_bpf(int cmd, union bpf_attr *attr,
6653 unsigned int size)
6654{
6655 u32 sid = current_sid();
6656 int ret;
6657
6658 switch (cmd) {
6659 case BPF_MAP_CREATE:
6660 ret = avc_has_perm(&selinux_state,
6661 sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6662 NULL);
6663 break;
6664 case BPF_PROG_LOAD:
6665 ret = avc_has_perm(&selinux_state,
6666 sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6667 NULL);
6668 break;
6669 default:
6670 ret = 0;
6671 break;
6672 }
6673
6674 return ret;
6675}
6676
6677static u32 bpf_map_fmode_to_av(fmode_t fmode)
6678{
6679 u32 av = 0;
6680
6681 if (fmode & FMODE_READ)
6682 av |= BPF__MAP_READ;
6683 if (fmode & FMODE_WRITE)
6684 av |= BPF__MAP_WRITE;
6685 return av;
6686}
6687
6688/* This function will check the file pass through unix socket or binder to see
6689 * if it is a bpf related object. And apply correspinding checks on the bpf
6690 * object based on the type. The bpf maps and programs, not like other files and
6691 * socket, are using a shared anonymous inode inside the kernel as their inode.
6692 * So checking that inode cannot identify if the process have privilege to
6693 * access the bpf object and that's why we have to add this additional check in
6694 * selinux_file_receive and selinux_binder_transfer_files.
6695 */
6696static int bpf_fd_pass(struct file *file, u32 sid)
6697{
6698 struct bpf_security_struct *bpfsec;
6699 struct bpf_prog *prog;
6700 struct bpf_map *map;
6701 int ret;
6702
6703 if (file->f_op == &bpf_map_fops) {
6704 map = file->private_data;
6705 bpfsec = map->security;
6706 ret = avc_has_perm(&selinux_state,
6707 sid, bpfsec->sid, SECCLASS_BPF,
6708 bpf_map_fmode_to_av(file->f_mode), NULL);
6709 if (ret)
6710 return ret;
6711 } else if (file->f_op == &bpf_prog_fops) {
6712 prog = file->private_data;
6713 bpfsec = prog->aux->security;
6714 ret = avc_has_perm(&selinux_state,
6715 sid, bpfsec->sid, SECCLASS_BPF,
6716 BPF__PROG_RUN, NULL);
6717 if (ret)
6718 return ret;
6719 }
6720 return 0;
6721}
6722
6723static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6724{
6725 u32 sid = current_sid();
6726 struct bpf_security_struct *bpfsec;
6727
6728 bpfsec = map->security;
6729 return avc_has_perm(&selinux_state,
6730 sid, bpfsec->sid, SECCLASS_BPF,
6731 bpf_map_fmode_to_av(fmode), NULL);
6732}
6733
6734static int selinux_bpf_prog(struct bpf_prog *prog)
6735{
6736 u32 sid = current_sid();
6737 struct bpf_security_struct *bpfsec;
6738
6739 bpfsec = prog->aux->security;
6740 return avc_has_perm(&selinux_state,
6741 sid, bpfsec->sid, SECCLASS_BPF,
6742 BPF__PROG_RUN, NULL);
6743}
6744
6745static int selinux_bpf_map_alloc(struct bpf_map *map)
6746{
6747 struct bpf_security_struct *bpfsec;
6748
6749 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6750 if (!bpfsec)
6751 return -ENOMEM;
6752
6753 bpfsec->sid = current_sid();
6754 map->security = bpfsec;
6755
6756 return 0;
6757}
6758
6759static void selinux_bpf_map_free(struct bpf_map *map)
6760{
6761 struct bpf_security_struct *bpfsec = map->security;
6762
6763 map->security = NULL;
6764 kfree(bpfsec);
6765}
6766
6767static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6768{
6769 struct bpf_security_struct *bpfsec;
6770
6771 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6772 if (!bpfsec)
6773 return -ENOMEM;
6774
6775 bpfsec->sid = current_sid();
6776 aux->security = bpfsec;
6777
6778 return 0;
6779}
6780
6781static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6782{
6783 struct bpf_security_struct *bpfsec = aux->security;
6784
6785 aux->security = NULL;
6786 kfree(bpfsec);
6787}
6788#endif
6789
6790struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
6791 .lbs_cred = sizeof(struct task_security_struct),
6792 .lbs_file = sizeof(struct file_security_struct),
6793 .lbs_inode = sizeof(struct inode_security_struct),
6794 .lbs_ipc = sizeof(struct ipc_security_struct),
6795 .lbs_msg_msg = sizeof(struct msg_security_struct),
6796};
6797
6798static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6799 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6800 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6801 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6802 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6803
6804 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6805 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6806 LSM_HOOK_INIT(capget, selinux_capget),
6807 LSM_HOOK_INIT(capset, selinux_capset),
6808 LSM_HOOK_INIT(capable, selinux_capable),
6809 LSM_HOOK_INIT(quotactl, selinux_quotactl),
6810 LSM_HOOK_INIT(quota_on, selinux_quota_on),
6811 LSM_HOOK_INIT(syslog, selinux_syslog),
6812 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6813
6814 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6815
6816 LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
6817 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6818 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6819
6820 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
6821 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
6822
6823 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
6824 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6825 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
6826 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
6827 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6828 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6829 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6830 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6831 LSM_HOOK_INIT(sb_mount, selinux_mount),
6832 LSM_HOOK_INIT(sb_umount, selinux_umount),
6833 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6834 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6835 LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt),
6836
6837 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6838 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6839
6840 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
6841 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6842 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6843 LSM_HOOK_INIT(inode_create, selinux_inode_create),
6844 LSM_HOOK_INIT(inode_link, selinux_inode_link),
6845 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6846 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6847 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6848 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6849 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6850 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6851 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
6852 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
6853 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
6854 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
6855 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
6856 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
6857 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
6858 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
6859 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
6860 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
6861 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
6862 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
6863 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
6864 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
6865 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6866 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6867 LSM_HOOK_INIT(path_notify, selinux_path_notify),
6868
6869 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
6870
6871 LSM_HOOK_INIT(file_permission, selinux_file_permission),
6872 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
6873 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
6874 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
6875 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
6876 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
6877 LSM_HOOK_INIT(file_lock, selinux_file_lock),
6878 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
6879 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
6880 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
6881 LSM_HOOK_INIT(file_receive, selinux_file_receive),
6882
6883 LSM_HOOK_INIT(file_open, selinux_file_open),
6884
6885 LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
6886 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
6887 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
6888 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
6889 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
6890 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
6891 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6892 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
6893 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6894 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
6895 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
6896 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
6897 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
6898 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
6899 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
6900 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6901 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
6902 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
6903 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
6904 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
6905 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
6906 LSM_HOOK_INIT(task_kill, selinux_task_kill),
6907 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
6908
6909 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
6910 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
6911
6912 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
6913
6914 LSM_HOOK_INIT(msg_queue_alloc_security,
6915 selinux_msg_queue_alloc_security),
6916 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
6917 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
6918 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
6919 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
6920
6921 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
6922 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
6923 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
6924 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
6925
6926 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
6927 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
6928 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
6929 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
6930
6931 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
6932
6933 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
6934 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
6935
6936 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
6937 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
6938 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
6939 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
6940 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6941 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
6942 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
6943 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
6944
6945 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
6946 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
6947
6948 LSM_HOOK_INIT(socket_create, selinux_socket_create),
6949 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
6950 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
6951 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
6952 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
6953 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
6954 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
6955 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
6956 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
6957 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
6958 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
6959 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
6960 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
6961 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
6962 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
6963 LSM_HOOK_INIT(socket_getpeersec_stream,
6964 selinux_socket_getpeersec_stream),
6965 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
6966 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
6967 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
6968 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
6969 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
6970 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
6971 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
6972 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
6973 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
6974 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
6975 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
6976 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
6977 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
6978 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
6979 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
6980 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
6981 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
6982 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
6983 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
6984 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
6985 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
6986 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
6987#ifdef CONFIG_SECURITY_INFINIBAND
6988 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
6989 LSM_HOOK_INIT(ib_endport_manage_subnet,
6990 selinux_ib_endport_manage_subnet),
6991 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
6992 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
6993#endif
6994#ifdef CONFIG_SECURITY_NETWORK_XFRM
6995 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
6996 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
6997 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
6998 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
6999 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7000 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7001 selinux_xfrm_state_alloc_acquire),
7002 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7003 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7004 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7005 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7006 selinux_xfrm_state_pol_flow_match),
7007 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7008#endif
7009
7010#ifdef CONFIG_KEYS
7011 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7012 LSM_HOOK_INIT(key_free, selinux_key_free),
7013 LSM_HOOK_INIT(key_permission, selinux_key_permission),
7014 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7015#endif
7016
7017#ifdef CONFIG_AUDIT
7018 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7019 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7020 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7021 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7022#endif
7023
7024#ifdef CONFIG_BPF_SYSCALL
7025 LSM_HOOK_INIT(bpf, selinux_bpf),
7026 LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7027 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7028 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7029 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7030 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7031 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7032#endif
7033};
7034
7035static __init int selinux_init(void)
7036{
7037 pr_info("SELinux: Initializing.\n");
7038
7039 memset(&selinux_state, 0, sizeof(selinux_state));
7040 enforcing_set(&selinux_state, selinux_enforcing_boot);
7041 selinux_state.checkreqprot = selinux_checkreqprot_boot;
7042 selinux_ss_init(&selinux_state.ss);
7043 selinux_avc_init(&selinux_state.avc);
7044
7045 /* Set the security state for the initial task. */
7046 cred_init_security();
7047
7048 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7049
7050 avc_init();
7051
7052 avtab_cache_init();
7053
7054 ebitmap_cache_init();
7055
7056 hashtab_cache_init();
7057
7058 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7059
7060 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7061 panic("SELinux: Unable to register AVC netcache callback\n");
7062
7063 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7064 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7065
7066 if (selinux_enforcing_boot)
7067 pr_debug("SELinux: Starting in enforcing mode\n");
7068 else
7069 pr_debug("SELinux: Starting in permissive mode\n");
7070
7071 fs_validate_description(&selinux_fs_parameters);
7072
7073 return 0;
7074}
7075
7076static void delayed_superblock_init(struct super_block *sb, void *unused)
7077{
7078 selinux_set_mnt_opts(sb, NULL, 0, NULL);
7079}
7080
7081void selinux_complete_init(void)
7082{
7083 pr_debug("SELinux: Completing initialization.\n");
7084
7085 /* Set up any superblocks initialized prior to the policy load. */
7086 pr_debug("SELinux: Setting up existing superblocks.\n");
7087 iterate_supers(delayed_superblock_init, NULL);
7088}
7089
7090/* SELinux requires early initialization in order to label
7091 all processes and objects when they are created. */
7092DEFINE_LSM(selinux) = {
7093 .name = "selinux",
7094 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7095 .enabled = &selinux_enabled,
7096 .blobs = &selinux_blob_sizes,
7097 .init = selinux_init,
7098};
7099
7100#if defined(CONFIG_NETFILTER)
7101
7102static const struct nf_hook_ops selinux_nf_ops[] = {
7103 {
7104 .hook = selinux_ipv4_postroute,
7105 .pf = NFPROTO_IPV4,
7106 .hooknum = NF_INET_POST_ROUTING,
7107 .priority = NF_IP_PRI_SELINUX_LAST,
7108 },
7109 {
7110 .hook = selinux_ipv4_forward,
7111 .pf = NFPROTO_IPV4,
7112 .hooknum = NF_INET_FORWARD,
7113 .priority = NF_IP_PRI_SELINUX_FIRST,
7114 },
7115 {
7116 .hook = selinux_ipv4_output,
7117 .pf = NFPROTO_IPV4,
7118 .hooknum = NF_INET_LOCAL_OUT,
7119 .priority = NF_IP_PRI_SELINUX_FIRST,
7120 },
7121#if IS_ENABLED(CONFIG_IPV6)
7122 {
7123 .hook = selinux_ipv6_postroute,
7124 .pf = NFPROTO_IPV6,
7125 .hooknum = NF_INET_POST_ROUTING,
7126 .priority = NF_IP6_PRI_SELINUX_LAST,
7127 },
7128 {
7129 .hook = selinux_ipv6_forward,
7130 .pf = NFPROTO_IPV6,
7131 .hooknum = NF_INET_FORWARD,
7132 .priority = NF_IP6_PRI_SELINUX_FIRST,
7133 },
7134 {
7135 .hook = selinux_ipv6_output,
7136 .pf = NFPROTO_IPV6,
7137 .hooknum = NF_INET_LOCAL_OUT,
7138 .priority = NF_IP6_PRI_SELINUX_FIRST,
7139 },
7140#endif /* IPV6 */
7141};
7142
7143static int __net_init selinux_nf_register(struct net *net)
7144{
7145 return nf_register_net_hooks(net, selinux_nf_ops,
7146 ARRAY_SIZE(selinux_nf_ops));
7147}
7148
7149static void __net_exit selinux_nf_unregister(struct net *net)
7150{
7151 nf_unregister_net_hooks(net, selinux_nf_ops,
7152 ARRAY_SIZE(selinux_nf_ops));
7153}
7154
7155static struct pernet_operations selinux_net_ops = {
7156 .init = selinux_nf_register,
7157 .exit = selinux_nf_unregister,
7158};
7159
7160static int __init selinux_nf_ip_init(void)
7161{
7162 int err;
7163
7164 if (!selinux_enabled)
7165 return 0;
7166
7167 pr_debug("SELinux: Registering netfilter hooks\n");
7168
7169 err = register_pernet_subsys(&selinux_net_ops);
7170 if (err)
7171 panic("SELinux: register_pernet_subsys: error %d\n", err);
7172
7173 return 0;
7174}
7175__initcall(selinux_nf_ip_init);
7176
7177#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7178static void selinux_nf_ip_exit(void)
7179{
7180 pr_debug("SELinux: Unregistering netfilter hooks\n");
7181
7182 unregister_pernet_subsys(&selinux_net_ops);
7183}
7184#endif
7185
7186#else /* CONFIG_NETFILTER */
7187
7188#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7189#define selinux_nf_ip_exit()
7190#endif
7191
7192#endif /* CONFIG_NETFILTER */
7193
7194#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7195int selinux_disable(struct selinux_state *state)
7196{
7197 if (state->initialized) {
7198 /* Not permitted after initial policy load. */
7199 return -EINVAL;
7200 }
7201
7202 if (state->disabled) {
7203 /* Only do this once. */
7204 return -EINVAL;
7205 }
7206
7207 state->disabled = 1;
7208
7209 pr_info("SELinux: Disabled at runtime.\n");
7210
7211 selinux_enabled = 0;
7212
7213 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7214
7215 /* Try to destroy the avc node cache */
7216 avc_disable();
7217
7218 /* Unregister netfilter hooks. */
7219 selinux_nf_ip_exit();
7220
7221 /* Unregister selinuxfs. */
7222 exit_sel_fs();
7223
7224 return 0;
7225}
7226#endif
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/ext2_fs.h>
32#include <linux/sched.h>
33#include <linux/security.h>
34#include <linux/xattr.h>
35#include <linux/capability.h>
36#include <linux/unistd.h>
37#include <linux/mm.h>
38#include <linux/mman.h>
39#include <linux/slab.h>
40#include <linux/pagemap.h>
41#include <linux/proc_fs.h>
42#include <linux/swap.h>
43#include <linux/spinlock.h>
44#include <linux/syscalls.h>
45#include <linux/dcache.h>
46#include <linux/file.h>
47#include <linux/fdtable.h>
48#include <linux/namei.h>
49#include <linux/mount.h>
50#include <linux/netfilter_ipv4.h>
51#include <linux/netfilter_ipv6.h>
52#include <linux/tty.h>
53#include <net/icmp.h>
54#include <net/ip.h> /* for local_port_range[] */
55#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
56#include <net/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 <linux/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
84#include "avc.h"
85#include "objsec.h"
86#include "netif.h"
87#include "netnode.h"
88#include "netport.h"
89#include "xfrm.h"
90#include "netlabel.h"
91#include "audit.h"
92
93#define NUM_SEL_MNT_OPTS 5
94
95extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
96extern struct security_operations *security_ops;
97
98/* SECMARK reference count */
99atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
100
101#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
102int selinux_enforcing;
103
104static int __init enforcing_setup(char *str)
105{
106 unsigned long enforcing;
107 if (!strict_strtoul(str, 0, &enforcing))
108 selinux_enforcing = enforcing ? 1 : 0;
109 return 1;
110}
111__setup("enforcing=", enforcing_setup);
112#endif
113
114#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
115int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
116
117static int __init selinux_enabled_setup(char *str)
118{
119 unsigned long enabled;
120 if (!strict_strtoul(str, 0, &enabled))
121 selinux_enabled = enabled ? 1 : 0;
122 return 1;
123}
124__setup("selinux=", selinux_enabled_setup);
125#else
126int selinux_enabled = 1;
127#endif
128
129static struct kmem_cache *sel_inode_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.
139 *
140 */
141static int selinux_secmark_enabled(void)
142{
143 return (atomic_read(&selinux_secmark_refcount) > 0);
144}
145
146/*
147 * initialise the security for the init task
148 */
149static void cred_init_security(void)
150{
151 struct cred *cred = (struct cred *) current->real_cred;
152 struct task_security_struct *tsec;
153
154 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
155 if (!tsec)
156 panic("SELinux: Failed to initialize initial task.\n");
157
158 tsec->osid = tsec->sid = SECINITSID_KERNEL;
159 cred->security = tsec;
160}
161
162/*
163 * get the security ID of a set of credentials
164 */
165static inline u32 cred_sid(const struct cred *cred)
166{
167 const struct task_security_struct *tsec;
168
169 tsec = cred->security;
170 return tsec->sid;
171}
172
173/*
174 * get the objective security ID of a task
175 */
176static inline u32 task_sid(const struct task_struct *task)
177{
178 u32 sid;
179
180 rcu_read_lock();
181 sid = cred_sid(__task_cred(task));
182 rcu_read_unlock();
183 return sid;
184}
185
186/*
187 * get the subjective security ID of the current task
188 */
189static inline u32 current_sid(void)
190{
191 const struct task_security_struct *tsec = current_security();
192
193 return tsec->sid;
194}
195
196/* Allocate and free functions for each kind of security blob. */
197
198static int inode_alloc_security(struct inode *inode)
199{
200 struct inode_security_struct *isec;
201 u32 sid = current_sid();
202
203 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
204 if (!isec)
205 return -ENOMEM;
206
207 mutex_init(&isec->lock);
208 INIT_LIST_HEAD(&isec->list);
209 isec->inode = inode;
210 isec->sid = SECINITSID_UNLABELED;
211 isec->sclass = SECCLASS_FILE;
212 isec->task_sid = sid;
213 inode->i_security = isec;
214
215 return 0;
216}
217
218static void inode_free_security(struct inode *inode)
219{
220 struct inode_security_struct *isec = inode->i_security;
221 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
222
223 spin_lock(&sbsec->isec_lock);
224 if (!list_empty(&isec->list))
225 list_del_init(&isec->list);
226 spin_unlock(&sbsec->isec_lock);
227
228 inode->i_security = NULL;
229 kmem_cache_free(sel_inode_cache, isec);
230}
231
232static int file_alloc_security(struct file *file)
233{
234 struct file_security_struct *fsec;
235 u32 sid = current_sid();
236
237 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
238 if (!fsec)
239 return -ENOMEM;
240
241 fsec->sid = sid;
242 fsec->fown_sid = sid;
243 file->f_security = fsec;
244
245 return 0;
246}
247
248static void file_free_security(struct file *file)
249{
250 struct file_security_struct *fsec = file->f_security;
251 file->f_security = NULL;
252 kfree(fsec);
253}
254
255static int superblock_alloc_security(struct super_block *sb)
256{
257 struct superblock_security_struct *sbsec;
258
259 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
260 if (!sbsec)
261 return -ENOMEM;
262
263 mutex_init(&sbsec->lock);
264 INIT_LIST_HEAD(&sbsec->isec_head);
265 spin_lock_init(&sbsec->isec_lock);
266 sbsec->sb = sb;
267 sbsec->sid = SECINITSID_UNLABELED;
268 sbsec->def_sid = SECINITSID_FILE;
269 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
270 sb->s_security = sbsec;
271
272 return 0;
273}
274
275static void superblock_free_security(struct super_block *sb)
276{
277 struct superblock_security_struct *sbsec = sb->s_security;
278 sb->s_security = NULL;
279 kfree(sbsec);
280}
281
282/* The security server must be initialized before
283 any labeling or access decisions can be provided. */
284extern int ss_initialized;
285
286/* The file system's label must be initialized prior to use. */
287
288static const char *labeling_behaviors[6] = {
289 "uses xattr",
290 "uses transition SIDs",
291 "uses task SIDs",
292 "uses genfs_contexts",
293 "not configured for labeling",
294 "uses mountpoint labeling",
295};
296
297static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
298
299static inline int inode_doinit(struct inode *inode)
300{
301 return inode_doinit_with_dentry(inode, NULL);
302}
303
304enum {
305 Opt_error = -1,
306 Opt_context = 1,
307 Opt_fscontext = 2,
308 Opt_defcontext = 3,
309 Opt_rootcontext = 4,
310 Opt_labelsupport = 5,
311};
312
313static const match_table_t tokens = {
314 {Opt_context, CONTEXT_STR "%s"},
315 {Opt_fscontext, FSCONTEXT_STR "%s"},
316 {Opt_defcontext, DEFCONTEXT_STR "%s"},
317 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
318 {Opt_labelsupport, LABELSUPP_STR},
319 {Opt_error, NULL},
320};
321
322#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
323
324static int may_context_mount_sb_relabel(u32 sid,
325 struct superblock_security_struct *sbsec,
326 const struct cred *cred)
327{
328 const struct task_security_struct *tsec = cred->security;
329 int rc;
330
331 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
332 FILESYSTEM__RELABELFROM, NULL);
333 if (rc)
334 return rc;
335
336 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
337 FILESYSTEM__RELABELTO, NULL);
338 return rc;
339}
340
341static int may_context_mount_inode_relabel(u32 sid,
342 struct superblock_security_struct *sbsec,
343 const struct cred *cred)
344{
345 const struct task_security_struct *tsec = cred->security;
346 int rc;
347 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
348 FILESYSTEM__RELABELFROM, NULL);
349 if (rc)
350 return rc;
351
352 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
353 FILESYSTEM__ASSOCIATE, NULL);
354 return rc;
355}
356
357static int sb_finish_set_opts(struct super_block *sb)
358{
359 struct superblock_security_struct *sbsec = sb->s_security;
360 struct dentry *root = sb->s_root;
361 struct inode *root_inode = root->d_inode;
362 int rc = 0;
363
364 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
365 /* Make sure that the xattr handler exists and that no
366 error other than -ENODATA is returned by getxattr on
367 the root directory. -ENODATA is ok, as this may be
368 the first boot of the SELinux kernel before we have
369 assigned xattr values to the filesystem. */
370 if (!root_inode->i_op->getxattr) {
371 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
372 "xattr support\n", sb->s_id, sb->s_type->name);
373 rc = -EOPNOTSUPP;
374 goto out;
375 }
376 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
377 if (rc < 0 && rc != -ENODATA) {
378 if (rc == -EOPNOTSUPP)
379 printk(KERN_WARNING "SELinux: (dev %s, type "
380 "%s) has no security xattr handler\n",
381 sb->s_id, sb->s_type->name);
382 else
383 printk(KERN_WARNING "SELinux: (dev %s, type "
384 "%s) getxattr errno %d\n", sb->s_id,
385 sb->s_type->name, -rc);
386 goto out;
387 }
388 }
389
390 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
391
392 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
393 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
394 sb->s_id, sb->s_type->name);
395 else
396 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
397 sb->s_id, sb->s_type->name,
398 labeling_behaviors[sbsec->behavior-1]);
399
400 if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
401 sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
402 sbsec->behavior == SECURITY_FS_USE_NONE ||
403 sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
404 sbsec->flags &= ~SE_SBLABELSUPP;
405
406 /* Special handling for sysfs. Is genfs but also has setxattr handler*/
407 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
408 sbsec->flags |= SE_SBLABELSUPP;
409
410 /* Initialize the root inode. */
411 rc = inode_doinit_with_dentry(root_inode, root);
412
413 /* Initialize any other inodes associated with the superblock, e.g.
414 inodes created prior to initial policy load or inodes created
415 during get_sb by a pseudo filesystem that directly
416 populates itself. */
417 spin_lock(&sbsec->isec_lock);
418next_inode:
419 if (!list_empty(&sbsec->isec_head)) {
420 struct inode_security_struct *isec =
421 list_entry(sbsec->isec_head.next,
422 struct inode_security_struct, list);
423 struct inode *inode = isec->inode;
424 spin_unlock(&sbsec->isec_lock);
425 inode = igrab(inode);
426 if (inode) {
427 if (!IS_PRIVATE(inode))
428 inode_doinit(inode);
429 iput(inode);
430 }
431 spin_lock(&sbsec->isec_lock);
432 list_del_init(&isec->list);
433 goto next_inode;
434 }
435 spin_unlock(&sbsec->isec_lock);
436out:
437 return rc;
438}
439
440/*
441 * This function should allow an FS to ask what it's mount security
442 * options were so it can use those later for submounts, displaying
443 * mount options, or whatever.
444 */
445static int selinux_get_mnt_opts(const struct super_block *sb,
446 struct security_mnt_opts *opts)
447{
448 int rc = 0, i;
449 struct superblock_security_struct *sbsec = sb->s_security;
450 char *context = NULL;
451 u32 len;
452 char tmp;
453
454 security_init_mnt_opts(opts);
455
456 if (!(sbsec->flags & SE_SBINITIALIZED))
457 return -EINVAL;
458
459 if (!ss_initialized)
460 return -EINVAL;
461
462 tmp = sbsec->flags & SE_MNTMASK;
463 /* count the number of mount options for this sb */
464 for (i = 0; i < 8; i++) {
465 if (tmp & 0x01)
466 opts->num_mnt_opts++;
467 tmp >>= 1;
468 }
469 /* Check if the Label support flag is set */
470 if (sbsec->flags & SE_SBLABELSUPP)
471 opts->num_mnt_opts++;
472
473 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
474 if (!opts->mnt_opts) {
475 rc = -ENOMEM;
476 goto out_free;
477 }
478
479 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
480 if (!opts->mnt_opts_flags) {
481 rc = -ENOMEM;
482 goto out_free;
483 }
484
485 i = 0;
486 if (sbsec->flags & FSCONTEXT_MNT) {
487 rc = security_sid_to_context(sbsec->sid, &context, &len);
488 if (rc)
489 goto out_free;
490 opts->mnt_opts[i] = context;
491 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
492 }
493 if (sbsec->flags & CONTEXT_MNT) {
494 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
495 if (rc)
496 goto out_free;
497 opts->mnt_opts[i] = context;
498 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
499 }
500 if (sbsec->flags & DEFCONTEXT_MNT) {
501 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
502 if (rc)
503 goto out_free;
504 opts->mnt_opts[i] = context;
505 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
506 }
507 if (sbsec->flags & ROOTCONTEXT_MNT) {
508 struct inode *root = sbsec->sb->s_root->d_inode;
509 struct inode_security_struct *isec = root->i_security;
510
511 rc = security_sid_to_context(isec->sid, &context, &len);
512 if (rc)
513 goto out_free;
514 opts->mnt_opts[i] = context;
515 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
516 }
517 if (sbsec->flags & SE_SBLABELSUPP) {
518 opts->mnt_opts[i] = NULL;
519 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
520 }
521
522 BUG_ON(i != opts->num_mnt_opts);
523
524 return 0;
525
526out_free:
527 security_free_mnt_opts(opts);
528 return rc;
529}
530
531static int bad_option(struct superblock_security_struct *sbsec, char flag,
532 u32 old_sid, u32 new_sid)
533{
534 char mnt_flags = sbsec->flags & SE_MNTMASK;
535
536 /* check if the old mount command had the same options */
537 if (sbsec->flags & SE_SBINITIALIZED)
538 if (!(sbsec->flags & flag) ||
539 (old_sid != new_sid))
540 return 1;
541
542 /* check if we were passed the same options twice,
543 * aka someone passed context=a,context=b
544 */
545 if (!(sbsec->flags & SE_SBINITIALIZED))
546 if (mnt_flags & flag)
547 return 1;
548 return 0;
549}
550
551/*
552 * Allow filesystems with binary mount data to explicitly set mount point
553 * labeling information.
554 */
555static int selinux_set_mnt_opts(struct super_block *sb,
556 struct security_mnt_opts *opts)
557{
558 const struct cred *cred = current_cred();
559 int rc = 0, i;
560 struct superblock_security_struct *sbsec = sb->s_security;
561 const char *name = sb->s_type->name;
562 struct inode *inode = sbsec->sb->s_root->d_inode;
563 struct inode_security_struct *root_isec = inode->i_security;
564 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
565 u32 defcontext_sid = 0;
566 char **mount_options = opts->mnt_opts;
567 int *flags = opts->mnt_opts_flags;
568 int num_opts = opts->num_mnt_opts;
569
570 mutex_lock(&sbsec->lock);
571
572 if (!ss_initialized) {
573 if (!num_opts) {
574 /* Defer initialization until selinux_complete_init,
575 after the initial policy is loaded and the security
576 server is ready to handle calls. */
577 goto out;
578 }
579 rc = -EINVAL;
580 printk(KERN_WARNING "SELinux: Unable to set superblock options "
581 "before the security server is initialized\n");
582 goto out;
583 }
584
585 /*
586 * Binary mount data FS will come through this function twice. Once
587 * from an explicit call and once from the generic calls from the vfs.
588 * Since the generic VFS calls will not contain any security mount data
589 * we need to skip the double mount verification.
590 *
591 * This does open a hole in which we will not notice if the first
592 * mount using this sb set explict options and a second mount using
593 * this sb does not set any security options. (The first options
594 * will be used for both mounts)
595 */
596 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
597 && (num_opts == 0))
598 goto out;
599
600 /*
601 * parse the mount options, check if they are valid sids.
602 * also check if someone is trying to mount the same sb more
603 * than once with different security options.
604 */
605 for (i = 0; i < num_opts; i++) {
606 u32 sid;
607
608 if (flags[i] == SE_SBLABELSUPP)
609 continue;
610 rc = security_context_to_sid(mount_options[i],
611 strlen(mount_options[i]), &sid);
612 if (rc) {
613 printk(KERN_WARNING "SELinux: security_context_to_sid"
614 "(%s) failed for (dev %s, type %s) errno=%d\n",
615 mount_options[i], sb->s_id, name, rc);
616 goto out;
617 }
618 switch (flags[i]) {
619 case FSCONTEXT_MNT:
620 fscontext_sid = sid;
621
622 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
623 fscontext_sid))
624 goto out_double_mount;
625
626 sbsec->flags |= FSCONTEXT_MNT;
627 break;
628 case CONTEXT_MNT:
629 context_sid = sid;
630
631 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
632 context_sid))
633 goto out_double_mount;
634
635 sbsec->flags |= CONTEXT_MNT;
636 break;
637 case ROOTCONTEXT_MNT:
638 rootcontext_sid = sid;
639
640 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
641 rootcontext_sid))
642 goto out_double_mount;
643
644 sbsec->flags |= ROOTCONTEXT_MNT;
645
646 break;
647 case DEFCONTEXT_MNT:
648 defcontext_sid = sid;
649
650 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
651 defcontext_sid))
652 goto out_double_mount;
653
654 sbsec->flags |= DEFCONTEXT_MNT;
655
656 break;
657 default:
658 rc = -EINVAL;
659 goto out;
660 }
661 }
662
663 if (sbsec->flags & SE_SBINITIALIZED) {
664 /* previously mounted with options, but not on this attempt? */
665 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
666 goto out_double_mount;
667 rc = 0;
668 goto out;
669 }
670
671 if (strcmp(sb->s_type->name, "proc") == 0)
672 sbsec->flags |= SE_SBPROC;
673
674 /* Determine the labeling behavior to use for this filesystem type. */
675 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
676 if (rc) {
677 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
678 __func__, sb->s_type->name, rc);
679 goto out;
680 }
681
682 /* sets the context of the superblock for the fs being mounted. */
683 if (fscontext_sid) {
684 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
685 if (rc)
686 goto out;
687
688 sbsec->sid = fscontext_sid;
689 }
690
691 /*
692 * Switch to using mount point labeling behavior.
693 * sets the label used on all file below the mountpoint, and will set
694 * the superblock context if not already set.
695 */
696 if (context_sid) {
697 if (!fscontext_sid) {
698 rc = may_context_mount_sb_relabel(context_sid, sbsec,
699 cred);
700 if (rc)
701 goto out;
702 sbsec->sid = context_sid;
703 } else {
704 rc = may_context_mount_inode_relabel(context_sid, sbsec,
705 cred);
706 if (rc)
707 goto out;
708 }
709 if (!rootcontext_sid)
710 rootcontext_sid = context_sid;
711
712 sbsec->mntpoint_sid = context_sid;
713 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
714 }
715
716 if (rootcontext_sid) {
717 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
718 cred);
719 if (rc)
720 goto out;
721
722 root_isec->sid = rootcontext_sid;
723 root_isec->initialized = 1;
724 }
725
726 if (defcontext_sid) {
727 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
728 rc = -EINVAL;
729 printk(KERN_WARNING "SELinux: defcontext option is "
730 "invalid for this filesystem type\n");
731 goto out;
732 }
733
734 if (defcontext_sid != sbsec->def_sid) {
735 rc = may_context_mount_inode_relabel(defcontext_sid,
736 sbsec, cred);
737 if (rc)
738 goto out;
739 }
740
741 sbsec->def_sid = defcontext_sid;
742 }
743
744 rc = sb_finish_set_opts(sb);
745out:
746 mutex_unlock(&sbsec->lock);
747 return rc;
748out_double_mount:
749 rc = -EINVAL;
750 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
751 "security settings for (dev %s, type %s)\n", sb->s_id, name);
752 goto out;
753}
754
755static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
756 struct super_block *newsb)
757{
758 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
759 struct superblock_security_struct *newsbsec = newsb->s_security;
760
761 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
762 int set_context = (oldsbsec->flags & CONTEXT_MNT);
763 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
764
765 /*
766 * if the parent was able to be mounted it clearly had no special lsm
767 * mount options. thus we can safely deal with this superblock later
768 */
769 if (!ss_initialized)
770 return;
771
772 /* how can we clone if the old one wasn't set up?? */
773 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
774
775 /* if fs is reusing a sb, just let its options stand... */
776 if (newsbsec->flags & SE_SBINITIALIZED)
777 return;
778
779 mutex_lock(&newsbsec->lock);
780
781 newsbsec->flags = oldsbsec->flags;
782
783 newsbsec->sid = oldsbsec->sid;
784 newsbsec->def_sid = oldsbsec->def_sid;
785 newsbsec->behavior = oldsbsec->behavior;
786
787 if (set_context) {
788 u32 sid = oldsbsec->mntpoint_sid;
789
790 if (!set_fscontext)
791 newsbsec->sid = sid;
792 if (!set_rootcontext) {
793 struct inode *newinode = newsb->s_root->d_inode;
794 struct inode_security_struct *newisec = newinode->i_security;
795 newisec->sid = sid;
796 }
797 newsbsec->mntpoint_sid = sid;
798 }
799 if (set_rootcontext) {
800 const struct inode *oldinode = oldsb->s_root->d_inode;
801 const struct inode_security_struct *oldisec = oldinode->i_security;
802 struct inode *newinode = newsb->s_root->d_inode;
803 struct inode_security_struct *newisec = newinode->i_security;
804
805 newisec->sid = oldisec->sid;
806 }
807
808 sb_finish_set_opts(newsb);
809 mutex_unlock(&newsbsec->lock);
810}
811
812static int selinux_parse_opts_str(char *options,
813 struct security_mnt_opts *opts)
814{
815 char *p;
816 char *context = NULL, *defcontext = NULL;
817 char *fscontext = NULL, *rootcontext = NULL;
818 int rc, num_mnt_opts = 0;
819
820 opts->num_mnt_opts = 0;
821
822 /* Standard string-based options. */
823 while ((p = strsep(&options, "|")) != NULL) {
824 int token;
825 substring_t args[MAX_OPT_ARGS];
826
827 if (!*p)
828 continue;
829
830 token = match_token(p, tokens, args);
831
832 switch (token) {
833 case Opt_context:
834 if (context || defcontext) {
835 rc = -EINVAL;
836 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
837 goto out_err;
838 }
839 context = match_strdup(&args[0]);
840 if (!context) {
841 rc = -ENOMEM;
842 goto out_err;
843 }
844 break;
845
846 case Opt_fscontext:
847 if (fscontext) {
848 rc = -EINVAL;
849 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
850 goto out_err;
851 }
852 fscontext = match_strdup(&args[0]);
853 if (!fscontext) {
854 rc = -ENOMEM;
855 goto out_err;
856 }
857 break;
858
859 case Opt_rootcontext:
860 if (rootcontext) {
861 rc = -EINVAL;
862 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
863 goto out_err;
864 }
865 rootcontext = match_strdup(&args[0]);
866 if (!rootcontext) {
867 rc = -ENOMEM;
868 goto out_err;
869 }
870 break;
871
872 case Opt_defcontext:
873 if (context || defcontext) {
874 rc = -EINVAL;
875 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
876 goto out_err;
877 }
878 defcontext = match_strdup(&args[0]);
879 if (!defcontext) {
880 rc = -ENOMEM;
881 goto out_err;
882 }
883 break;
884 case Opt_labelsupport:
885 break;
886 default:
887 rc = -EINVAL;
888 printk(KERN_WARNING "SELinux: unknown mount option\n");
889 goto out_err;
890
891 }
892 }
893
894 rc = -ENOMEM;
895 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
896 if (!opts->mnt_opts)
897 goto out_err;
898
899 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
900 if (!opts->mnt_opts_flags) {
901 kfree(opts->mnt_opts);
902 goto out_err;
903 }
904
905 if (fscontext) {
906 opts->mnt_opts[num_mnt_opts] = fscontext;
907 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
908 }
909 if (context) {
910 opts->mnt_opts[num_mnt_opts] = context;
911 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
912 }
913 if (rootcontext) {
914 opts->mnt_opts[num_mnt_opts] = rootcontext;
915 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
916 }
917 if (defcontext) {
918 opts->mnt_opts[num_mnt_opts] = defcontext;
919 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
920 }
921
922 opts->num_mnt_opts = num_mnt_opts;
923 return 0;
924
925out_err:
926 kfree(context);
927 kfree(defcontext);
928 kfree(fscontext);
929 kfree(rootcontext);
930 return rc;
931}
932/*
933 * string mount options parsing and call set the sbsec
934 */
935static int superblock_doinit(struct super_block *sb, void *data)
936{
937 int rc = 0;
938 char *options = data;
939 struct security_mnt_opts opts;
940
941 security_init_mnt_opts(&opts);
942
943 if (!data)
944 goto out;
945
946 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
947
948 rc = selinux_parse_opts_str(options, &opts);
949 if (rc)
950 goto out_err;
951
952out:
953 rc = selinux_set_mnt_opts(sb, &opts);
954
955out_err:
956 security_free_mnt_opts(&opts);
957 return rc;
958}
959
960static void selinux_write_opts(struct seq_file *m,
961 struct security_mnt_opts *opts)
962{
963 int i;
964 char *prefix;
965
966 for (i = 0; i < opts->num_mnt_opts; i++) {
967 char *has_comma;
968
969 if (opts->mnt_opts[i])
970 has_comma = strchr(opts->mnt_opts[i], ',');
971 else
972 has_comma = NULL;
973
974 switch (opts->mnt_opts_flags[i]) {
975 case CONTEXT_MNT:
976 prefix = CONTEXT_STR;
977 break;
978 case FSCONTEXT_MNT:
979 prefix = FSCONTEXT_STR;
980 break;
981 case ROOTCONTEXT_MNT:
982 prefix = ROOTCONTEXT_STR;
983 break;
984 case DEFCONTEXT_MNT:
985 prefix = DEFCONTEXT_STR;
986 break;
987 case SE_SBLABELSUPP:
988 seq_putc(m, ',');
989 seq_puts(m, LABELSUPP_STR);
990 continue;
991 default:
992 BUG();
993 return;
994 };
995 /* we need a comma before each option */
996 seq_putc(m, ',');
997 seq_puts(m, prefix);
998 if (has_comma)
999 seq_putc(m, '\"');
1000 seq_puts(m, opts->mnt_opts[i]);
1001 if (has_comma)
1002 seq_putc(m, '\"');
1003 }
1004}
1005
1006static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1007{
1008 struct security_mnt_opts opts;
1009 int rc;
1010
1011 rc = selinux_get_mnt_opts(sb, &opts);
1012 if (rc) {
1013 /* before policy load we may get EINVAL, don't show anything */
1014 if (rc == -EINVAL)
1015 rc = 0;
1016 return rc;
1017 }
1018
1019 selinux_write_opts(m, &opts);
1020
1021 security_free_mnt_opts(&opts);
1022
1023 return rc;
1024}
1025
1026static inline u16 inode_mode_to_security_class(umode_t mode)
1027{
1028 switch (mode & S_IFMT) {
1029 case S_IFSOCK:
1030 return SECCLASS_SOCK_FILE;
1031 case S_IFLNK:
1032 return SECCLASS_LNK_FILE;
1033 case S_IFREG:
1034 return SECCLASS_FILE;
1035 case S_IFBLK:
1036 return SECCLASS_BLK_FILE;
1037 case S_IFDIR:
1038 return SECCLASS_DIR;
1039 case S_IFCHR:
1040 return SECCLASS_CHR_FILE;
1041 case S_IFIFO:
1042 return SECCLASS_FIFO_FILE;
1043
1044 }
1045
1046 return SECCLASS_FILE;
1047}
1048
1049static inline int default_protocol_stream(int protocol)
1050{
1051 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1052}
1053
1054static inline int default_protocol_dgram(int protocol)
1055{
1056 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1057}
1058
1059static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1060{
1061 switch (family) {
1062 case PF_UNIX:
1063 switch (type) {
1064 case SOCK_STREAM:
1065 case SOCK_SEQPACKET:
1066 return SECCLASS_UNIX_STREAM_SOCKET;
1067 case SOCK_DGRAM:
1068 return SECCLASS_UNIX_DGRAM_SOCKET;
1069 }
1070 break;
1071 case PF_INET:
1072 case PF_INET6:
1073 switch (type) {
1074 case SOCK_STREAM:
1075 if (default_protocol_stream(protocol))
1076 return SECCLASS_TCP_SOCKET;
1077 else
1078 return SECCLASS_RAWIP_SOCKET;
1079 case SOCK_DGRAM:
1080 if (default_protocol_dgram(protocol))
1081 return SECCLASS_UDP_SOCKET;
1082 else
1083 return SECCLASS_RAWIP_SOCKET;
1084 case SOCK_DCCP:
1085 return SECCLASS_DCCP_SOCKET;
1086 default:
1087 return SECCLASS_RAWIP_SOCKET;
1088 }
1089 break;
1090 case PF_NETLINK:
1091 switch (protocol) {
1092 case NETLINK_ROUTE:
1093 return SECCLASS_NETLINK_ROUTE_SOCKET;
1094 case NETLINK_FIREWALL:
1095 return SECCLASS_NETLINK_FIREWALL_SOCKET;
1096 case NETLINK_INET_DIAG:
1097 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1098 case NETLINK_NFLOG:
1099 return SECCLASS_NETLINK_NFLOG_SOCKET;
1100 case NETLINK_XFRM:
1101 return SECCLASS_NETLINK_XFRM_SOCKET;
1102 case NETLINK_SELINUX:
1103 return SECCLASS_NETLINK_SELINUX_SOCKET;
1104 case NETLINK_AUDIT:
1105 return SECCLASS_NETLINK_AUDIT_SOCKET;
1106 case NETLINK_IP6_FW:
1107 return SECCLASS_NETLINK_IP6FW_SOCKET;
1108 case NETLINK_DNRTMSG:
1109 return SECCLASS_NETLINK_DNRT_SOCKET;
1110 case NETLINK_KOBJECT_UEVENT:
1111 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1112 default:
1113 return SECCLASS_NETLINK_SOCKET;
1114 }
1115 case PF_PACKET:
1116 return SECCLASS_PACKET_SOCKET;
1117 case PF_KEY:
1118 return SECCLASS_KEY_SOCKET;
1119 case PF_APPLETALK:
1120 return SECCLASS_APPLETALK_SOCKET;
1121 }
1122
1123 return SECCLASS_SOCKET;
1124}
1125
1126#ifdef CONFIG_PROC_FS
1127static int selinux_proc_get_sid(struct dentry *dentry,
1128 u16 tclass,
1129 u32 *sid)
1130{
1131 int rc;
1132 char *buffer, *path;
1133
1134 buffer = (char *)__get_free_page(GFP_KERNEL);
1135 if (!buffer)
1136 return -ENOMEM;
1137
1138 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1139 if (IS_ERR(path))
1140 rc = PTR_ERR(path);
1141 else {
1142 /* each process gets a /proc/PID/ entry. Strip off the
1143 * PID part to get a valid selinux labeling.
1144 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1145 while (path[1] >= '0' && path[1] <= '9') {
1146 path[1] = '/';
1147 path++;
1148 }
1149 rc = security_genfs_sid("proc", path, tclass, sid);
1150 }
1151 free_page((unsigned long)buffer);
1152 return rc;
1153}
1154#else
1155static int selinux_proc_get_sid(struct dentry *dentry,
1156 u16 tclass,
1157 u32 *sid)
1158{
1159 return -EINVAL;
1160}
1161#endif
1162
1163/* The inode's security attributes must be initialized before first use. */
1164static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1165{
1166 struct superblock_security_struct *sbsec = NULL;
1167 struct inode_security_struct *isec = inode->i_security;
1168 u32 sid;
1169 struct dentry *dentry;
1170#define INITCONTEXTLEN 255
1171 char *context = NULL;
1172 unsigned len = 0;
1173 int rc = 0;
1174
1175 if (isec->initialized)
1176 goto out;
1177
1178 mutex_lock(&isec->lock);
1179 if (isec->initialized)
1180 goto out_unlock;
1181
1182 sbsec = inode->i_sb->s_security;
1183 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1184 /* Defer initialization until selinux_complete_init,
1185 after the initial policy is loaded and the security
1186 server is ready to handle calls. */
1187 spin_lock(&sbsec->isec_lock);
1188 if (list_empty(&isec->list))
1189 list_add(&isec->list, &sbsec->isec_head);
1190 spin_unlock(&sbsec->isec_lock);
1191 goto out_unlock;
1192 }
1193
1194 switch (sbsec->behavior) {
1195 case SECURITY_FS_USE_XATTR:
1196 if (!inode->i_op->getxattr) {
1197 isec->sid = sbsec->def_sid;
1198 break;
1199 }
1200
1201 /* Need a dentry, since the xattr API requires one.
1202 Life would be simpler if we could just pass the inode. */
1203 if (opt_dentry) {
1204 /* Called from d_instantiate or d_splice_alias. */
1205 dentry = dget(opt_dentry);
1206 } else {
1207 /* Called from selinux_complete_init, try to find a dentry. */
1208 dentry = d_find_alias(inode);
1209 }
1210 if (!dentry) {
1211 /*
1212 * this is can be hit on boot when a file is accessed
1213 * before the policy is loaded. When we load policy we
1214 * may find inodes that have no dentry on the
1215 * sbsec->isec_head list. No reason to complain as these
1216 * will get fixed up the next time we go through
1217 * inode_doinit with a dentry, before these inodes could
1218 * be used again by userspace.
1219 */
1220 goto out_unlock;
1221 }
1222
1223 len = INITCONTEXTLEN;
1224 context = kmalloc(len+1, GFP_NOFS);
1225 if (!context) {
1226 rc = -ENOMEM;
1227 dput(dentry);
1228 goto out_unlock;
1229 }
1230 context[len] = '\0';
1231 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1232 context, len);
1233 if (rc == -ERANGE) {
1234 kfree(context);
1235
1236 /* Need a larger buffer. Query for the right size. */
1237 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1238 NULL, 0);
1239 if (rc < 0) {
1240 dput(dentry);
1241 goto out_unlock;
1242 }
1243 len = rc;
1244 context = kmalloc(len+1, GFP_NOFS);
1245 if (!context) {
1246 rc = -ENOMEM;
1247 dput(dentry);
1248 goto out_unlock;
1249 }
1250 context[len] = '\0';
1251 rc = inode->i_op->getxattr(dentry,
1252 XATTR_NAME_SELINUX,
1253 context, len);
1254 }
1255 dput(dentry);
1256 if (rc < 0) {
1257 if (rc != -ENODATA) {
1258 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1259 "%d for dev=%s ino=%ld\n", __func__,
1260 -rc, inode->i_sb->s_id, inode->i_ino);
1261 kfree(context);
1262 goto out_unlock;
1263 }
1264 /* Map ENODATA to the default file SID */
1265 sid = sbsec->def_sid;
1266 rc = 0;
1267 } else {
1268 rc = security_context_to_sid_default(context, rc, &sid,
1269 sbsec->def_sid,
1270 GFP_NOFS);
1271 if (rc) {
1272 char *dev = inode->i_sb->s_id;
1273 unsigned long ino = inode->i_ino;
1274
1275 if (rc == -EINVAL) {
1276 if (printk_ratelimit())
1277 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1278 "context=%s. This indicates you may need to relabel the inode or the "
1279 "filesystem in question.\n", ino, dev, context);
1280 } else {
1281 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1282 "returned %d for dev=%s ino=%ld\n",
1283 __func__, context, -rc, dev, ino);
1284 }
1285 kfree(context);
1286 /* Leave with the unlabeled SID */
1287 rc = 0;
1288 break;
1289 }
1290 }
1291 kfree(context);
1292 isec->sid = sid;
1293 break;
1294 case SECURITY_FS_USE_TASK:
1295 isec->sid = isec->task_sid;
1296 break;
1297 case SECURITY_FS_USE_TRANS:
1298 /* Default to the fs SID. */
1299 isec->sid = sbsec->sid;
1300
1301 /* Try to obtain a transition SID. */
1302 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1303 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1304 isec->sclass, NULL, &sid);
1305 if (rc)
1306 goto out_unlock;
1307 isec->sid = sid;
1308 break;
1309 case SECURITY_FS_USE_MNTPOINT:
1310 isec->sid = sbsec->mntpoint_sid;
1311 break;
1312 default:
1313 /* Default to the fs superblock SID. */
1314 isec->sid = sbsec->sid;
1315
1316 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1317 if (opt_dentry) {
1318 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1319 rc = selinux_proc_get_sid(opt_dentry,
1320 isec->sclass,
1321 &sid);
1322 if (rc)
1323 goto out_unlock;
1324 isec->sid = sid;
1325 }
1326 }
1327 break;
1328 }
1329
1330 isec->initialized = 1;
1331
1332out_unlock:
1333 mutex_unlock(&isec->lock);
1334out:
1335 if (isec->sclass == SECCLASS_FILE)
1336 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1337 return rc;
1338}
1339
1340/* Convert a Linux signal to an access vector. */
1341static inline u32 signal_to_av(int sig)
1342{
1343 u32 perm = 0;
1344
1345 switch (sig) {
1346 case SIGCHLD:
1347 /* Commonly granted from child to parent. */
1348 perm = PROCESS__SIGCHLD;
1349 break;
1350 case SIGKILL:
1351 /* Cannot be caught or ignored */
1352 perm = PROCESS__SIGKILL;
1353 break;
1354 case SIGSTOP:
1355 /* Cannot be caught or ignored */
1356 perm = PROCESS__SIGSTOP;
1357 break;
1358 default:
1359 /* All other signals. */
1360 perm = PROCESS__SIGNAL;
1361 break;
1362 }
1363
1364 return perm;
1365}
1366
1367/*
1368 * Check permission between a pair of credentials
1369 * fork check, ptrace check, etc.
1370 */
1371static int cred_has_perm(const struct cred *actor,
1372 const struct cred *target,
1373 u32 perms)
1374{
1375 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1376
1377 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1378}
1379
1380/*
1381 * Check permission between a pair of tasks, e.g. signal checks,
1382 * fork check, ptrace check, etc.
1383 * tsk1 is the actor and tsk2 is the target
1384 * - this uses the default subjective creds of tsk1
1385 */
1386static int task_has_perm(const struct task_struct *tsk1,
1387 const struct task_struct *tsk2,
1388 u32 perms)
1389{
1390 const struct task_security_struct *__tsec1, *__tsec2;
1391 u32 sid1, sid2;
1392
1393 rcu_read_lock();
1394 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1395 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1396 rcu_read_unlock();
1397 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1398}
1399
1400/*
1401 * Check permission between current and another task, e.g. signal checks,
1402 * fork check, ptrace check, etc.
1403 * current is the actor and tsk2 is the target
1404 * - this uses current's subjective creds
1405 */
1406static int current_has_perm(const struct task_struct *tsk,
1407 u32 perms)
1408{
1409 u32 sid, tsid;
1410
1411 sid = current_sid();
1412 tsid = task_sid(tsk);
1413 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1414}
1415
1416#if CAP_LAST_CAP > 63
1417#error Fix SELinux to handle capabilities > 63.
1418#endif
1419
1420/* Check whether a task is allowed to use a capability. */
1421static int task_has_capability(struct task_struct *tsk,
1422 const struct cred *cred,
1423 int cap, int audit)
1424{
1425 struct common_audit_data ad;
1426 struct av_decision avd;
1427 u16 sclass;
1428 u32 sid = cred_sid(cred);
1429 u32 av = CAP_TO_MASK(cap);
1430 int rc;
1431
1432 COMMON_AUDIT_DATA_INIT(&ad, CAP);
1433 ad.tsk = tsk;
1434 ad.u.cap = cap;
1435
1436 switch (CAP_TO_INDEX(cap)) {
1437 case 0:
1438 sclass = SECCLASS_CAPABILITY;
1439 break;
1440 case 1:
1441 sclass = SECCLASS_CAPABILITY2;
1442 break;
1443 default:
1444 printk(KERN_ERR
1445 "SELinux: out of range capability %d\n", cap);
1446 BUG();
1447 return -EINVAL;
1448 }
1449
1450 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1451 if (audit == SECURITY_CAP_AUDIT) {
1452 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1453 if (rc2)
1454 return rc2;
1455 }
1456 return rc;
1457}
1458
1459/* Check whether a task is allowed to use a system operation. */
1460static int task_has_system(struct task_struct *tsk,
1461 u32 perms)
1462{
1463 u32 sid = task_sid(tsk);
1464
1465 return avc_has_perm(sid, SECINITSID_KERNEL,
1466 SECCLASS_SYSTEM, perms, NULL);
1467}
1468
1469/* Check whether a task has a particular permission to an inode.
1470 The 'adp' parameter is optional and allows other audit
1471 data to be passed (e.g. the dentry). */
1472static int inode_has_perm(const struct cred *cred,
1473 struct inode *inode,
1474 u32 perms,
1475 struct common_audit_data *adp,
1476 unsigned flags)
1477{
1478 struct inode_security_struct *isec;
1479 u32 sid;
1480
1481 validate_creds(cred);
1482
1483 if (unlikely(IS_PRIVATE(inode)))
1484 return 0;
1485
1486 sid = cred_sid(cred);
1487 isec = inode->i_security;
1488
1489 return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1490}
1491
1492static int inode_has_perm_noadp(const struct cred *cred,
1493 struct inode *inode,
1494 u32 perms,
1495 unsigned flags)
1496{
1497 struct common_audit_data ad;
1498
1499 COMMON_AUDIT_DATA_INIT(&ad, INODE);
1500 ad.u.inode = inode;
1501 return inode_has_perm(cred, inode, perms, &ad, flags);
1502}
1503
1504/* Same as inode_has_perm, but pass explicit audit data containing
1505 the dentry to help the auditing code to more easily generate the
1506 pathname if needed. */
1507static inline int dentry_has_perm(const struct cred *cred,
1508 struct dentry *dentry,
1509 u32 av)
1510{
1511 struct inode *inode = dentry->d_inode;
1512 struct common_audit_data ad;
1513
1514 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1515 ad.u.dentry = dentry;
1516 return inode_has_perm(cred, inode, av, &ad, 0);
1517}
1518
1519/* Same as inode_has_perm, but pass explicit audit data containing
1520 the path to help the auditing code to more easily generate the
1521 pathname if needed. */
1522static inline int path_has_perm(const struct cred *cred,
1523 struct path *path,
1524 u32 av)
1525{
1526 struct inode *inode = path->dentry->d_inode;
1527 struct common_audit_data ad;
1528
1529 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1530 ad.u.path = *path;
1531 return inode_has_perm(cred, inode, av, &ad, 0);
1532}
1533
1534/* Check whether a task can use an open file descriptor to
1535 access an inode in a given way. Check access to the
1536 descriptor itself, and then use dentry_has_perm to
1537 check a particular permission to the file.
1538 Access to the descriptor is implicitly granted if it
1539 has the same SID as the process. If av is zero, then
1540 access to the file is not checked, e.g. for cases
1541 where only the descriptor is affected like seek. */
1542static int file_has_perm(const struct cred *cred,
1543 struct file *file,
1544 u32 av)
1545{
1546 struct file_security_struct *fsec = file->f_security;
1547 struct inode *inode = file->f_path.dentry->d_inode;
1548 struct common_audit_data ad;
1549 u32 sid = cred_sid(cred);
1550 int rc;
1551
1552 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1553 ad.u.path = file->f_path;
1554
1555 if (sid != fsec->sid) {
1556 rc = avc_has_perm(sid, fsec->sid,
1557 SECCLASS_FD,
1558 FD__USE,
1559 &ad);
1560 if (rc)
1561 goto out;
1562 }
1563
1564 /* av is zero if only checking access to the descriptor. */
1565 rc = 0;
1566 if (av)
1567 rc = inode_has_perm(cred, inode, av, &ad, 0);
1568
1569out:
1570 return rc;
1571}
1572
1573/* Check whether a task can create a file. */
1574static int may_create(struct inode *dir,
1575 struct dentry *dentry,
1576 u16 tclass)
1577{
1578 const struct task_security_struct *tsec = current_security();
1579 struct inode_security_struct *dsec;
1580 struct superblock_security_struct *sbsec;
1581 u32 sid, newsid;
1582 struct common_audit_data ad;
1583 int rc;
1584
1585 dsec = dir->i_security;
1586 sbsec = dir->i_sb->s_security;
1587
1588 sid = tsec->sid;
1589 newsid = tsec->create_sid;
1590
1591 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1592 ad.u.dentry = dentry;
1593
1594 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1595 DIR__ADD_NAME | DIR__SEARCH,
1596 &ad);
1597 if (rc)
1598 return rc;
1599
1600 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1601 rc = security_transition_sid(sid, dsec->sid, tclass,
1602 &dentry->d_name, &newsid);
1603 if (rc)
1604 return rc;
1605 }
1606
1607 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1608 if (rc)
1609 return rc;
1610
1611 return avc_has_perm(newsid, sbsec->sid,
1612 SECCLASS_FILESYSTEM,
1613 FILESYSTEM__ASSOCIATE, &ad);
1614}
1615
1616/* Check whether a task can create a key. */
1617static int may_create_key(u32 ksid,
1618 struct task_struct *ctx)
1619{
1620 u32 sid = task_sid(ctx);
1621
1622 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1623}
1624
1625#define MAY_LINK 0
1626#define MAY_UNLINK 1
1627#define MAY_RMDIR 2
1628
1629/* Check whether a task can link, unlink, or rmdir a file/directory. */
1630static int may_link(struct inode *dir,
1631 struct dentry *dentry,
1632 int kind)
1633
1634{
1635 struct inode_security_struct *dsec, *isec;
1636 struct common_audit_data ad;
1637 u32 sid = current_sid();
1638 u32 av;
1639 int rc;
1640
1641 dsec = dir->i_security;
1642 isec = dentry->d_inode->i_security;
1643
1644 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1645 ad.u.dentry = dentry;
1646
1647 av = DIR__SEARCH;
1648 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1649 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1650 if (rc)
1651 return rc;
1652
1653 switch (kind) {
1654 case MAY_LINK:
1655 av = FILE__LINK;
1656 break;
1657 case MAY_UNLINK:
1658 av = FILE__UNLINK;
1659 break;
1660 case MAY_RMDIR:
1661 av = DIR__RMDIR;
1662 break;
1663 default:
1664 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1665 __func__, kind);
1666 return 0;
1667 }
1668
1669 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1670 return rc;
1671}
1672
1673static inline int may_rename(struct inode *old_dir,
1674 struct dentry *old_dentry,
1675 struct inode *new_dir,
1676 struct dentry *new_dentry)
1677{
1678 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1679 struct common_audit_data ad;
1680 u32 sid = current_sid();
1681 u32 av;
1682 int old_is_dir, new_is_dir;
1683 int rc;
1684
1685 old_dsec = old_dir->i_security;
1686 old_isec = old_dentry->d_inode->i_security;
1687 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1688 new_dsec = new_dir->i_security;
1689
1690 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1691
1692 ad.u.dentry = old_dentry;
1693 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1694 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1695 if (rc)
1696 return rc;
1697 rc = avc_has_perm(sid, old_isec->sid,
1698 old_isec->sclass, FILE__RENAME, &ad);
1699 if (rc)
1700 return rc;
1701 if (old_is_dir && new_dir != old_dir) {
1702 rc = avc_has_perm(sid, old_isec->sid,
1703 old_isec->sclass, DIR__REPARENT, &ad);
1704 if (rc)
1705 return rc;
1706 }
1707
1708 ad.u.dentry = new_dentry;
1709 av = DIR__ADD_NAME | DIR__SEARCH;
1710 if (new_dentry->d_inode)
1711 av |= DIR__REMOVE_NAME;
1712 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1713 if (rc)
1714 return rc;
1715 if (new_dentry->d_inode) {
1716 new_isec = new_dentry->d_inode->i_security;
1717 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1718 rc = avc_has_perm(sid, new_isec->sid,
1719 new_isec->sclass,
1720 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1721 if (rc)
1722 return rc;
1723 }
1724
1725 return 0;
1726}
1727
1728/* Check whether a task can perform a filesystem operation. */
1729static int superblock_has_perm(const struct cred *cred,
1730 struct super_block *sb,
1731 u32 perms,
1732 struct common_audit_data *ad)
1733{
1734 struct superblock_security_struct *sbsec;
1735 u32 sid = cred_sid(cred);
1736
1737 sbsec = sb->s_security;
1738 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1739}
1740
1741/* Convert a Linux mode and permission mask to an access vector. */
1742static inline u32 file_mask_to_av(int mode, int mask)
1743{
1744 u32 av = 0;
1745
1746 if ((mode & S_IFMT) != S_IFDIR) {
1747 if (mask & MAY_EXEC)
1748 av |= FILE__EXECUTE;
1749 if (mask & MAY_READ)
1750 av |= FILE__READ;
1751
1752 if (mask & MAY_APPEND)
1753 av |= FILE__APPEND;
1754 else if (mask & MAY_WRITE)
1755 av |= FILE__WRITE;
1756
1757 } else {
1758 if (mask & MAY_EXEC)
1759 av |= DIR__SEARCH;
1760 if (mask & MAY_WRITE)
1761 av |= DIR__WRITE;
1762 if (mask & MAY_READ)
1763 av |= DIR__READ;
1764 }
1765
1766 return av;
1767}
1768
1769/* Convert a Linux file to an access vector. */
1770static inline u32 file_to_av(struct file *file)
1771{
1772 u32 av = 0;
1773
1774 if (file->f_mode & FMODE_READ)
1775 av |= FILE__READ;
1776 if (file->f_mode & FMODE_WRITE) {
1777 if (file->f_flags & O_APPEND)
1778 av |= FILE__APPEND;
1779 else
1780 av |= FILE__WRITE;
1781 }
1782 if (!av) {
1783 /*
1784 * Special file opened with flags 3 for ioctl-only use.
1785 */
1786 av = FILE__IOCTL;
1787 }
1788
1789 return av;
1790}
1791
1792/*
1793 * Convert a file to an access vector and include the correct open
1794 * open permission.
1795 */
1796static inline u32 open_file_to_av(struct file *file)
1797{
1798 u32 av = file_to_av(file);
1799
1800 if (selinux_policycap_openperm)
1801 av |= FILE__OPEN;
1802
1803 return av;
1804}
1805
1806/* Hook functions begin here. */
1807
1808static int selinux_ptrace_access_check(struct task_struct *child,
1809 unsigned int mode)
1810{
1811 int rc;
1812
1813 rc = cap_ptrace_access_check(child, mode);
1814 if (rc)
1815 return rc;
1816
1817 if (mode == PTRACE_MODE_READ) {
1818 u32 sid = current_sid();
1819 u32 csid = task_sid(child);
1820 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1821 }
1822
1823 return current_has_perm(child, PROCESS__PTRACE);
1824}
1825
1826static int selinux_ptrace_traceme(struct task_struct *parent)
1827{
1828 int rc;
1829
1830 rc = cap_ptrace_traceme(parent);
1831 if (rc)
1832 return rc;
1833
1834 return task_has_perm(parent, current, PROCESS__PTRACE);
1835}
1836
1837static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1838 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1839{
1840 int error;
1841
1842 error = current_has_perm(target, PROCESS__GETCAP);
1843 if (error)
1844 return error;
1845
1846 return cap_capget(target, effective, inheritable, permitted);
1847}
1848
1849static int selinux_capset(struct cred *new, const struct cred *old,
1850 const kernel_cap_t *effective,
1851 const kernel_cap_t *inheritable,
1852 const kernel_cap_t *permitted)
1853{
1854 int error;
1855
1856 error = cap_capset(new, old,
1857 effective, inheritable, permitted);
1858 if (error)
1859 return error;
1860
1861 return cred_has_perm(old, new, PROCESS__SETCAP);
1862}
1863
1864/*
1865 * (This comment used to live with the selinux_task_setuid hook,
1866 * which was removed).
1867 *
1868 * Since setuid only affects the current process, and since the SELinux
1869 * controls are not based on the Linux identity attributes, SELinux does not
1870 * need to control this operation. However, SELinux does control the use of
1871 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1872 */
1873
1874static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1875 struct user_namespace *ns, int cap, int audit)
1876{
1877 int rc;
1878
1879 rc = cap_capable(tsk, cred, ns, cap, audit);
1880 if (rc)
1881 return rc;
1882
1883 return task_has_capability(tsk, cred, cap, audit);
1884}
1885
1886static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1887{
1888 const struct cred *cred = current_cred();
1889 int rc = 0;
1890
1891 if (!sb)
1892 return 0;
1893
1894 switch (cmds) {
1895 case Q_SYNC:
1896 case Q_QUOTAON:
1897 case Q_QUOTAOFF:
1898 case Q_SETINFO:
1899 case Q_SETQUOTA:
1900 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1901 break;
1902 case Q_GETFMT:
1903 case Q_GETINFO:
1904 case Q_GETQUOTA:
1905 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1906 break;
1907 default:
1908 rc = 0; /* let the kernel handle invalid cmds */
1909 break;
1910 }
1911 return rc;
1912}
1913
1914static int selinux_quota_on(struct dentry *dentry)
1915{
1916 const struct cred *cred = current_cred();
1917
1918 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1919}
1920
1921static int selinux_syslog(int type)
1922{
1923 int rc;
1924
1925 switch (type) {
1926 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
1927 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1928 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1929 break;
1930 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1931 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
1932 /* Set level of messages printed to console */
1933 case SYSLOG_ACTION_CONSOLE_LEVEL:
1934 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1935 break;
1936 case SYSLOG_ACTION_CLOSE: /* Close log */
1937 case SYSLOG_ACTION_OPEN: /* Open log */
1938 case SYSLOG_ACTION_READ: /* Read from log */
1939 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
1940 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
1941 default:
1942 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1943 break;
1944 }
1945 return rc;
1946}
1947
1948/*
1949 * Check that a process has enough memory to allocate a new virtual
1950 * mapping. 0 means there is enough memory for the allocation to
1951 * succeed and -ENOMEM implies there is not.
1952 *
1953 * Do not audit the selinux permission check, as this is applied to all
1954 * processes that allocate mappings.
1955 */
1956static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1957{
1958 int rc, cap_sys_admin = 0;
1959
1960 rc = selinux_capable(current, current_cred(),
1961 &init_user_ns, CAP_SYS_ADMIN,
1962 SECURITY_CAP_NOAUDIT);
1963 if (rc == 0)
1964 cap_sys_admin = 1;
1965
1966 return __vm_enough_memory(mm, pages, cap_sys_admin);
1967}
1968
1969/* binprm security operations */
1970
1971static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1972{
1973 const struct task_security_struct *old_tsec;
1974 struct task_security_struct *new_tsec;
1975 struct inode_security_struct *isec;
1976 struct common_audit_data ad;
1977 struct inode *inode = bprm->file->f_path.dentry->d_inode;
1978 int rc;
1979
1980 rc = cap_bprm_set_creds(bprm);
1981 if (rc)
1982 return rc;
1983
1984 /* SELinux context only depends on initial program or script and not
1985 * the script interpreter */
1986 if (bprm->cred_prepared)
1987 return 0;
1988
1989 old_tsec = current_security();
1990 new_tsec = bprm->cred->security;
1991 isec = inode->i_security;
1992
1993 /* Default to the current task SID. */
1994 new_tsec->sid = old_tsec->sid;
1995 new_tsec->osid = old_tsec->sid;
1996
1997 /* Reset fs, key, and sock SIDs on execve. */
1998 new_tsec->create_sid = 0;
1999 new_tsec->keycreate_sid = 0;
2000 new_tsec->sockcreate_sid = 0;
2001
2002 if (old_tsec->exec_sid) {
2003 new_tsec->sid = old_tsec->exec_sid;
2004 /* Reset exec SID on execve. */
2005 new_tsec->exec_sid = 0;
2006 } else {
2007 /* Check for a default transition on this program. */
2008 rc = security_transition_sid(old_tsec->sid, isec->sid,
2009 SECCLASS_PROCESS, NULL,
2010 &new_tsec->sid);
2011 if (rc)
2012 return rc;
2013 }
2014
2015 COMMON_AUDIT_DATA_INIT(&ad, PATH);
2016 ad.u.path = bprm->file->f_path;
2017
2018 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2019 new_tsec->sid = old_tsec->sid;
2020
2021 if (new_tsec->sid == old_tsec->sid) {
2022 rc = avc_has_perm(old_tsec->sid, isec->sid,
2023 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2024 if (rc)
2025 return rc;
2026 } else {
2027 /* Check permissions for the transition. */
2028 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2029 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2030 if (rc)
2031 return rc;
2032
2033 rc = avc_has_perm(new_tsec->sid, isec->sid,
2034 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2035 if (rc)
2036 return rc;
2037
2038 /* Check for shared state */
2039 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2040 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2041 SECCLASS_PROCESS, PROCESS__SHARE,
2042 NULL);
2043 if (rc)
2044 return -EPERM;
2045 }
2046
2047 /* Make sure that anyone attempting to ptrace over a task that
2048 * changes its SID has the appropriate permit */
2049 if (bprm->unsafe &
2050 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2051 struct task_struct *tracer;
2052 struct task_security_struct *sec;
2053 u32 ptsid = 0;
2054
2055 rcu_read_lock();
2056 tracer = ptrace_parent(current);
2057 if (likely(tracer != NULL)) {
2058 sec = __task_cred(tracer)->security;
2059 ptsid = sec->sid;
2060 }
2061 rcu_read_unlock();
2062
2063 if (ptsid != 0) {
2064 rc = avc_has_perm(ptsid, new_tsec->sid,
2065 SECCLASS_PROCESS,
2066 PROCESS__PTRACE, NULL);
2067 if (rc)
2068 return -EPERM;
2069 }
2070 }
2071
2072 /* Clear any possibly unsafe personality bits on exec: */
2073 bprm->per_clear |= PER_CLEAR_ON_SETID;
2074 }
2075
2076 return 0;
2077}
2078
2079static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2080{
2081 const struct task_security_struct *tsec = current_security();
2082 u32 sid, osid;
2083 int atsecure = 0;
2084
2085 sid = tsec->sid;
2086 osid = tsec->osid;
2087
2088 if (osid != sid) {
2089 /* Enable secure mode for SIDs transitions unless
2090 the noatsecure permission is granted between
2091 the two SIDs, i.e. ahp returns 0. */
2092 atsecure = avc_has_perm(osid, sid,
2093 SECCLASS_PROCESS,
2094 PROCESS__NOATSECURE, NULL);
2095 }
2096
2097 return (atsecure || cap_bprm_secureexec(bprm));
2098}
2099
2100extern struct vfsmount *selinuxfs_mount;
2101extern struct dentry *selinux_null;
2102
2103/* Derived from fs/exec.c:flush_old_files. */
2104static inline void flush_unauthorized_files(const struct cred *cred,
2105 struct files_struct *files)
2106{
2107 struct common_audit_data ad;
2108 struct file *file, *devnull = NULL;
2109 struct tty_struct *tty;
2110 struct fdtable *fdt;
2111 long j = -1;
2112 int drop_tty = 0;
2113
2114 tty = get_current_tty();
2115 if (tty) {
2116 spin_lock(&tty_files_lock);
2117 if (!list_empty(&tty->tty_files)) {
2118 struct tty_file_private *file_priv;
2119 struct inode *inode;
2120
2121 /* Revalidate access to controlling tty.
2122 Use inode_has_perm on the tty inode directly rather
2123 than using file_has_perm, as this particular open
2124 file may belong to another process and we are only
2125 interested in the inode-based check here. */
2126 file_priv = list_first_entry(&tty->tty_files,
2127 struct tty_file_private, list);
2128 file = file_priv->file;
2129 inode = file->f_path.dentry->d_inode;
2130 if (inode_has_perm_noadp(cred, inode,
2131 FILE__READ | FILE__WRITE, 0)) {
2132 drop_tty = 1;
2133 }
2134 }
2135 spin_unlock(&tty_files_lock);
2136 tty_kref_put(tty);
2137 }
2138 /* Reset controlling tty. */
2139 if (drop_tty)
2140 no_tty();
2141
2142 /* Revalidate access to inherited open files. */
2143
2144 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2145
2146 spin_lock(&files->file_lock);
2147 for (;;) {
2148 unsigned long set, i;
2149 int fd;
2150
2151 j++;
2152 i = j * __NFDBITS;
2153 fdt = files_fdtable(files);
2154 if (i >= fdt->max_fds)
2155 break;
2156 set = fdt->open_fds->fds_bits[j];
2157 if (!set)
2158 continue;
2159 spin_unlock(&files->file_lock);
2160 for ( ; set ; i++, set >>= 1) {
2161 if (set & 1) {
2162 file = fget(i);
2163 if (!file)
2164 continue;
2165 if (file_has_perm(cred,
2166 file,
2167 file_to_av(file))) {
2168 sys_close(i);
2169 fd = get_unused_fd();
2170 if (fd != i) {
2171 if (fd >= 0)
2172 put_unused_fd(fd);
2173 fput(file);
2174 continue;
2175 }
2176 if (devnull) {
2177 get_file(devnull);
2178 } else {
2179 devnull = dentry_open(
2180 dget(selinux_null),
2181 mntget(selinuxfs_mount),
2182 O_RDWR, cred);
2183 if (IS_ERR(devnull)) {
2184 devnull = NULL;
2185 put_unused_fd(fd);
2186 fput(file);
2187 continue;
2188 }
2189 }
2190 fd_install(fd, devnull);
2191 }
2192 fput(file);
2193 }
2194 }
2195 spin_lock(&files->file_lock);
2196
2197 }
2198 spin_unlock(&files->file_lock);
2199}
2200
2201/*
2202 * Prepare a process for imminent new credential changes due to exec
2203 */
2204static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2205{
2206 struct task_security_struct *new_tsec;
2207 struct rlimit *rlim, *initrlim;
2208 int rc, i;
2209
2210 new_tsec = bprm->cred->security;
2211 if (new_tsec->sid == new_tsec->osid)
2212 return;
2213
2214 /* Close files for which the new task SID is not authorized. */
2215 flush_unauthorized_files(bprm->cred, current->files);
2216
2217 /* Always clear parent death signal on SID transitions. */
2218 current->pdeath_signal = 0;
2219
2220 /* Check whether the new SID can inherit resource limits from the old
2221 * SID. If not, reset all soft limits to the lower of the current
2222 * task's hard limit and the init task's soft limit.
2223 *
2224 * Note that the setting of hard limits (even to lower them) can be
2225 * controlled by the setrlimit check. The inclusion of the init task's
2226 * soft limit into the computation is to avoid resetting soft limits
2227 * higher than the default soft limit for cases where the default is
2228 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2229 */
2230 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2231 PROCESS__RLIMITINH, NULL);
2232 if (rc) {
2233 /* protect against do_prlimit() */
2234 task_lock(current);
2235 for (i = 0; i < RLIM_NLIMITS; i++) {
2236 rlim = current->signal->rlim + i;
2237 initrlim = init_task.signal->rlim + i;
2238 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2239 }
2240 task_unlock(current);
2241 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2242 }
2243}
2244
2245/*
2246 * Clean up the process immediately after the installation of new credentials
2247 * due to exec
2248 */
2249static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2250{
2251 const struct task_security_struct *tsec = current_security();
2252 struct itimerval itimer;
2253 u32 osid, sid;
2254 int rc, i;
2255
2256 osid = tsec->osid;
2257 sid = tsec->sid;
2258
2259 if (sid == osid)
2260 return;
2261
2262 /* Check whether the new SID can inherit signal state from the old SID.
2263 * If not, clear itimers to avoid subsequent signal generation and
2264 * flush and unblock signals.
2265 *
2266 * This must occur _after_ the task SID has been updated so that any
2267 * kill done after the flush will be checked against the new SID.
2268 */
2269 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2270 if (rc) {
2271 memset(&itimer, 0, sizeof itimer);
2272 for (i = 0; i < 3; i++)
2273 do_setitimer(i, &itimer, NULL);
2274 spin_lock_irq(¤t->sighand->siglock);
2275 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2276 __flush_signals(current);
2277 flush_signal_handlers(current, 1);
2278 sigemptyset(¤t->blocked);
2279 }
2280 spin_unlock_irq(¤t->sighand->siglock);
2281 }
2282
2283 /* Wake up the parent if it is waiting so that it can recheck
2284 * wait permission to the new task SID. */
2285 read_lock(&tasklist_lock);
2286 __wake_up_parent(current, current->real_parent);
2287 read_unlock(&tasklist_lock);
2288}
2289
2290/* superblock security operations */
2291
2292static int selinux_sb_alloc_security(struct super_block *sb)
2293{
2294 return superblock_alloc_security(sb);
2295}
2296
2297static void selinux_sb_free_security(struct super_block *sb)
2298{
2299 superblock_free_security(sb);
2300}
2301
2302static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2303{
2304 if (plen > olen)
2305 return 0;
2306
2307 return !memcmp(prefix, option, plen);
2308}
2309
2310static inline int selinux_option(char *option, int len)
2311{
2312 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2313 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2314 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2315 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2316 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2317}
2318
2319static inline void take_option(char **to, char *from, int *first, int len)
2320{
2321 if (!*first) {
2322 **to = ',';
2323 *to += 1;
2324 } else
2325 *first = 0;
2326 memcpy(*to, from, len);
2327 *to += len;
2328}
2329
2330static inline void take_selinux_option(char **to, char *from, int *first,
2331 int len)
2332{
2333 int current_size = 0;
2334
2335 if (!*first) {
2336 **to = '|';
2337 *to += 1;
2338 } else
2339 *first = 0;
2340
2341 while (current_size < len) {
2342 if (*from != '"') {
2343 **to = *from;
2344 *to += 1;
2345 }
2346 from += 1;
2347 current_size += 1;
2348 }
2349}
2350
2351static int selinux_sb_copy_data(char *orig, char *copy)
2352{
2353 int fnosec, fsec, rc = 0;
2354 char *in_save, *in_curr, *in_end;
2355 char *sec_curr, *nosec_save, *nosec;
2356 int open_quote = 0;
2357
2358 in_curr = orig;
2359 sec_curr = copy;
2360
2361 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2362 if (!nosec) {
2363 rc = -ENOMEM;
2364 goto out;
2365 }
2366
2367 nosec_save = nosec;
2368 fnosec = fsec = 1;
2369 in_save = in_end = orig;
2370
2371 do {
2372 if (*in_end == '"')
2373 open_quote = !open_quote;
2374 if ((*in_end == ',' && open_quote == 0) ||
2375 *in_end == '\0') {
2376 int len = in_end - in_curr;
2377
2378 if (selinux_option(in_curr, len))
2379 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2380 else
2381 take_option(&nosec, in_curr, &fnosec, len);
2382
2383 in_curr = in_end + 1;
2384 }
2385 } while (*in_end++);
2386
2387 strcpy(in_save, nosec_save);
2388 free_page((unsigned long)nosec_save);
2389out:
2390 return rc;
2391}
2392
2393static int selinux_sb_remount(struct super_block *sb, void *data)
2394{
2395 int rc, i, *flags;
2396 struct security_mnt_opts opts;
2397 char *secdata, **mount_options;
2398 struct superblock_security_struct *sbsec = sb->s_security;
2399
2400 if (!(sbsec->flags & SE_SBINITIALIZED))
2401 return 0;
2402
2403 if (!data)
2404 return 0;
2405
2406 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2407 return 0;
2408
2409 security_init_mnt_opts(&opts);
2410 secdata = alloc_secdata();
2411 if (!secdata)
2412 return -ENOMEM;
2413 rc = selinux_sb_copy_data(data, secdata);
2414 if (rc)
2415 goto out_free_secdata;
2416
2417 rc = selinux_parse_opts_str(secdata, &opts);
2418 if (rc)
2419 goto out_free_secdata;
2420
2421 mount_options = opts.mnt_opts;
2422 flags = opts.mnt_opts_flags;
2423
2424 for (i = 0; i < opts.num_mnt_opts; i++) {
2425 u32 sid;
2426 size_t len;
2427
2428 if (flags[i] == SE_SBLABELSUPP)
2429 continue;
2430 len = strlen(mount_options[i]);
2431 rc = security_context_to_sid(mount_options[i], len, &sid);
2432 if (rc) {
2433 printk(KERN_WARNING "SELinux: security_context_to_sid"
2434 "(%s) failed for (dev %s, type %s) errno=%d\n",
2435 mount_options[i], sb->s_id, sb->s_type->name, rc);
2436 goto out_free_opts;
2437 }
2438 rc = -EINVAL;
2439 switch (flags[i]) {
2440 case FSCONTEXT_MNT:
2441 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2442 goto out_bad_option;
2443 break;
2444 case CONTEXT_MNT:
2445 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2446 goto out_bad_option;
2447 break;
2448 case ROOTCONTEXT_MNT: {
2449 struct inode_security_struct *root_isec;
2450 root_isec = sb->s_root->d_inode->i_security;
2451
2452 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2453 goto out_bad_option;
2454 break;
2455 }
2456 case DEFCONTEXT_MNT:
2457 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2458 goto out_bad_option;
2459 break;
2460 default:
2461 goto out_free_opts;
2462 }
2463 }
2464
2465 rc = 0;
2466out_free_opts:
2467 security_free_mnt_opts(&opts);
2468out_free_secdata:
2469 free_secdata(secdata);
2470 return rc;
2471out_bad_option:
2472 printk(KERN_WARNING "SELinux: unable to change security options "
2473 "during remount (dev %s, type=%s)\n", sb->s_id,
2474 sb->s_type->name);
2475 goto out_free_opts;
2476}
2477
2478static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2479{
2480 const struct cred *cred = current_cred();
2481 struct common_audit_data ad;
2482 int rc;
2483
2484 rc = superblock_doinit(sb, data);
2485 if (rc)
2486 return rc;
2487
2488 /* Allow all mounts performed by the kernel */
2489 if (flags & MS_KERNMOUNT)
2490 return 0;
2491
2492 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2493 ad.u.dentry = sb->s_root;
2494 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2495}
2496
2497static int selinux_sb_statfs(struct dentry *dentry)
2498{
2499 const struct cred *cred = current_cred();
2500 struct common_audit_data ad;
2501
2502 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2503 ad.u.dentry = dentry->d_sb->s_root;
2504 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2505}
2506
2507static int selinux_mount(char *dev_name,
2508 struct path *path,
2509 char *type,
2510 unsigned long flags,
2511 void *data)
2512{
2513 const struct cred *cred = current_cred();
2514
2515 if (flags & MS_REMOUNT)
2516 return superblock_has_perm(cred, path->mnt->mnt_sb,
2517 FILESYSTEM__REMOUNT, NULL);
2518 else
2519 return path_has_perm(cred, path, FILE__MOUNTON);
2520}
2521
2522static int selinux_umount(struct vfsmount *mnt, int flags)
2523{
2524 const struct cred *cred = current_cred();
2525
2526 return superblock_has_perm(cred, mnt->mnt_sb,
2527 FILESYSTEM__UNMOUNT, NULL);
2528}
2529
2530/* inode security operations */
2531
2532static int selinux_inode_alloc_security(struct inode *inode)
2533{
2534 return inode_alloc_security(inode);
2535}
2536
2537static void selinux_inode_free_security(struct inode *inode)
2538{
2539 inode_free_security(inode);
2540}
2541
2542static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2543 const struct qstr *qstr, char **name,
2544 void **value, size_t *len)
2545{
2546 const struct task_security_struct *tsec = current_security();
2547 struct inode_security_struct *dsec;
2548 struct superblock_security_struct *sbsec;
2549 u32 sid, newsid, clen;
2550 int rc;
2551 char *namep = NULL, *context;
2552
2553 dsec = dir->i_security;
2554 sbsec = dir->i_sb->s_security;
2555
2556 sid = tsec->sid;
2557 newsid = tsec->create_sid;
2558
2559 if ((sbsec->flags & SE_SBINITIALIZED) &&
2560 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2561 newsid = sbsec->mntpoint_sid;
2562 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2563 rc = security_transition_sid(sid, dsec->sid,
2564 inode_mode_to_security_class(inode->i_mode),
2565 qstr, &newsid);
2566 if (rc) {
2567 printk(KERN_WARNING "%s: "
2568 "security_transition_sid failed, rc=%d (dev=%s "
2569 "ino=%ld)\n",
2570 __func__,
2571 -rc, inode->i_sb->s_id, inode->i_ino);
2572 return rc;
2573 }
2574 }
2575
2576 /* Possibly defer initialization to selinux_complete_init. */
2577 if (sbsec->flags & SE_SBINITIALIZED) {
2578 struct inode_security_struct *isec = inode->i_security;
2579 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2580 isec->sid = newsid;
2581 isec->initialized = 1;
2582 }
2583
2584 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2585 return -EOPNOTSUPP;
2586
2587 if (name) {
2588 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2589 if (!namep)
2590 return -ENOMEM;
2591 *name = namep;
2592 }
2593
2594 if (value && len) {
2595 rc = security_sid_to_context_force(newsid, &context, &clen);
2596 if (rc) {
2597 kfree(namep);
2598 return rc;
2599 }
2600 *value = context;
2601 *len = clen;
2602 }
2603
2604 return 0;
2605}
2606
2607static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2608{
2609 return may_create(dir, dentry, SECCLASS_FILE);
2610}
2611
2612static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2613{
2614 return may_link(dir, old_dentry, MAY_LINK);
2615}
2616
2617static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2618{
2619 return may_link(dir, dentry, MAY_UNLINK);
2620}
2621
2622static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2623{
2624 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2625}
2626
2627static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2628{
2629 return may_create(dir, dentry, SECCLASS_DIR);
2630}
2631
2632static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2633{
2634 return may_link(dir, dentry, MAY_RMDIR);
2635}
2636
2637static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2638{
2639 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2640}
2641
2642static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2643 struct inode *new_inode, struct dentry *new_dentry)
2644{
2645 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2646}
2647
2648static int selinux_inode_readlink(struct dentry *dentry)
2649{
2650 const struct cred *cred = current_cred();
2651
2652 return dentry_has_perm(cred, dentry, FILE__READ);
2653}
2654
2655static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2656{
2657 const struct cred *cred = current_cred();
2658
2659 return dentry_has_perm(cred, dentry, FILE__READ);
2660}
2661
2662static int selinux_inode_permission(struct inode *inode, int mask)
2663{
2664 const struct cred *cred = current_cred();
2665 struct common_audit_data ad;
2666 u32 perms;
2667 bool from_access;
2668 unsigned flags = mask & MAY_NOT_BLOCK;
2669
2670 from_access = mask & MAY_ACCESS;
2671 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2672
2673 /* No permission to check. Existence test. */
2674 if (!mask)
2675 return 0;
2676
2677 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2678 ad.u.inode = inode;
2679
2680 if (from_access)
2681 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2682
2683 perms = file_mask_to_av(inode->i_mode, mask);
2684
2685 return inode_has_perm(cred, inode, perms, &ad, flags);
2686}
2687
2688static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2689{
2690 const struct cred *cred = current_cred();
2691 unsigned int ia_valid = iattr->ia_valid;
2692
2693 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2694 if (ia_valid & ATTR_FORCE) {
2695 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2696 ATTR_FORCE);
2697 if (!ia_valid)
2698 return 0;
2699 }
2700
2701 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2702 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2703 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2704
2705 return dentry_has_perm(cred, dentry, FILE__WRITE);
2706}
2707
2708static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2709{
2710 const struct cred *cred = current_cred();
2711 struct path path;
2712
2713 path.dentry = dentry;
2714 path.mnt = mnt;
2715
2716 return path_has_perm(cred, &path, FILE__GETATTR);
2717}
2718
2719static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2720{
2721 const struct cred *cred = current_cred();
2722
2723 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2724 sizeof XATTR_SECURITY_PREFIX - 1)) {
2725 if (!strcmp(name, XATTR_NAME_CAPS)) {
2726 if (!capable(CAP_SETFCAP))
2727 return -EPERM;
2728 } else if (!capable(CAP_SYS_ADMIN)) {
2729 /* A different attribute in the security namespace.
2730 Restrict to administrator. */
2731 return -EPERM;
2732 }
2733 }
2734
2735 /* Not an attribute we recognize, so just check the
2736 ordinary setattr permission. */
2737 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2738}
2739
2740static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2741 const void *value, size_t size, int flags)
2742{
2743 struct inode *inode = dentry->d_inode;
2744 struct inode_security_struct *isec = inode->i_security;
2745 struct superblock_security_struct *sbsec;
2746 struct common_audit_data ad;
2747 u32 newsid, sid = current_sid();
2748 int rc = 0;
2749
2750 if (strcmp(name, XATTR_NAME_SELINUX))
2751 return selinux_inode_setotherxattr(dentry, name);
2752
2753 sbsec = inode->i_sb->s_security;
2754 if (!(sbsec->flags & SE_SBLABELSUPP))
2755 return -EOPNOTSUPP;
2756
2757 if (!inode_owner_or_capable(inode))
2758 return -EPERM;
2759
2760 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2761 ad.u.dentry = dentry;
2762
2763 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2764 FILE__RELABELFROM, &ad);
2765 if (rc)
2766 return rc;
2767
2768 rc = security_context_to_sid(value, size, &newsid);
2769 if (rc == -EINVAL) {
2770 if (!capable(CAP_MAC_ADMIN))
2771 return rc;
2772 rc = security_context_to_sid_force(value, size, &newsid);
2773 }
2774 if (rc)
2775 return rc;
2776
2777 rc = avc_has_perm(sid, newsid, isec->sclass,
2778 FILE__RELABELTO, &ad);
2779 if (rc)
2780 return rc;
2781
2782 rc = security_validate_transition(isec->sid, newsid, sid,
2783 isec->sclass);
2784 if (rc)
2785 return rc;
2786
2787 return avc_has_perm(newsid,
2788 sbsec->sid,
2789 SECCLASS_FILESYSTEM,
2790 FILESYSTEM__ASSOCIATE,
2791 &ad);
2792}
2793
2794static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2795 const void *value, size_t size,
2796 int flags)
2797{
2798 struct inode *inode = dentry->d_inode;
2799 struct inode_security_struct *isec = inode->i_security;
2800 u32 newsid;
2801 int rc;
2802
2803 if (strcmp(name, XATTR_NAME_SELINUX)) {
2804 /* Not an attribute we recognize, so nothing to do. */
2805 return;
2806 }
2807
2808 rc = security_context_to_sid_force(value, size, &newsid);
2809 if (rc) {
2810 printk(KERN_ERR "SELinux: unable to map context to SID"
2811 "for (%s, %lu), rc=%d\n",
2812 inode->i_sb->s_id, inode->i_ino, -rc);
2813 return;
2814 }
2815
2816 isec->sid = newsid;
2817 return;
2818}
2819
2820static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2821{
2822 const struct cred *cred = current_cred();
2823
2824 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2825}
2826
2827static int selinux_inode_listxattr(struct dentry *dentry)
2828{
2829 const struct cred *cred = current_cred();
2830
2831 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2832}
2833
2834static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2835{
2836 if (strcmp(name, XATTR_NAME_SELINUX))
2837 return selinux_inode_setotherxattr(dentry, name);
2838
2839 /* No one is allowed to remove a SELinux security label.
2840 You can change the label, but all data must be labeled. */
2841 return -EACCES;
2842}
2843
2844/*
2845 * Copy the inode security context value to the user.
2846 *
2847 * Permission check is handled by selinux_inode_getxattr hook.
2848 */
2849static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2850{
2851 u32 size;
2852 int error;
2853 char *context = NULL;
2854 struct inode_security_struct *isec = inode->i_security;
2855
2856 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2857 return -EOPNOTSUPP;
2858
2859 /*
2860 * If the caller has CAP_MAC_ADMIN, then get the raw context
2861 * value even if it is not defined by current policy; otherwise,
2862 * use the in-core value under current policy.
2863 * Use the non-auditing forms of the permission checks since
2864 * getxattr may be called by unprivileged processes commonly
2865 * and lack of permission just means that we fall back to the
2866 * in-core context value, not a denial.
2867 */
2868 error = selinux_capable(current, current_cred(),
2869 &init_user_ns, CAP_MAC_ADMIN,
2870 SECURITY_CAP_NOAUDIT);
2871 if (!error)
2872 error = security_sid_to_context_force(isec->sid, &context,
2873 &size);
2874 else
2875 error = security_sid_to_context(isec->sid, &context, &size);
2876 if (error)
2877 return error;
2878 error = size;
2879 if (alloc) {
2880 *buffer = context;
2881 goto out_nofree;
2882 }
2883 kfree(context);
2884out_nofree:
2885 return error;
2886}
2887
2888static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2889 const void *value, size_t size, int flags)
2890{
2891 struct inode_security_struct *isec = inode->i_security;
2892 u32 newsid;
2893 int rc;
2894
2895 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2896 return -EOPNOTSUPP;
2897
2898 if (!value || !size)
2899 return -EACCES;
2900
2901 rc = security_context_to_sid((void *)value, size, &newsid);
2902 if (rc)
2903 return rc;
2904
2905 isec->sid = newsid;
2906 isec->initialized = 1;
2907 return 0;
2908}
2909
2910static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2911{
2912 const int len = sizeof(XATTR_NAME_SELINUX);
2913 if (buffer && len <= buffer_size)
2914 memcpy(buffer, XATTR_NAME_SELINUX, len);
2915 return len;
2916}
2917
2918static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2919{
2920 struct inode_security_struct *isec = inode->i_security;
2921 *secid = isec->sid;
2922}
2923
2924/* file security operations */
2925
2926static int selinux_revalidate_file_permission(struct file *file, int mask)
2927{
2928 const struct cred *cred = current_cred();
2929 struct inode *inode = file->f_path.dentry->d_inode;
2930
2931 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2932 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2933 mask |= MAY_APPEND;
2934
2935 return file_has_perm(cred, file,
2936 file_mask_to_av(inode->i_mode, mask));
2937}
2938
2939static int selinux_file_permission(struct file *file, int mask)
2940{
2941 struct inode *inode = file->f_path.dentry->d_inode;
2942 struct file_security_struct *fsec = file->f_security;
2943 struct inode_security_struct *isec = inode->i_security;
2944 u32 sid = current_sid();
2945
2946 if (!mask)
2947 /* No permission to check. Existence test. */
2948 return 0;
2949
2950 if (sid == fsec->sid && fsec->isid == isec->sid &&
2951 fsec->pseqno == avc_policy_seqno())
2952 /* No change since dentry_open check. */
2953 return 0;
2954
2955 return selinux_revalidate_file_permission(file, mask);
2956}
2957
2958static int selinux_file_alloc_security(struct file *file)
2959{
2960 return file_alloc_security(file);
2961}
2962
2963static void selinux_file_free_security(struct file *file)
2964{
2965 file_free_security(file);
2966}
2967
2968static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2969 unsigned long arg)
2970{
2971 const struct cred *cred = current_cred();
2972 int error = 0;
2973
2974 switch (cmd) {
2975 case FIONREAD:
2976 /* fall through */
2977 case FIBMAP:
2978 /* fall through */
2979 case FIGETBSZ:
2980 /* fall through */
2981 case EXT2_IOC_GETFLAGS:
2982 /* fall through */
2983 case EXT2_IOC_GETVERSION:
2984 error = file_has_perm(cred, file, FILE__GETATTR);
2985 break;
2986
2987 case EXT2_IOC_SETFLAGS:
2988 /* fall through */
2989 case EXT2_IOC_SETVERSION:
2990 error = file_has_perm(cred, file, FILE__SETATTR);
2991 break;
2992
2993 /* sys_ioctl() checks */
2994 case FIONBIO:
2995 /* fall through */
2996 case FIOASYNC:
2997 error = file_has_perm(cred, file, 0);
2998 break;
2999
3000 case KDSKBENT:
3001 case KDSKBSENT:
3002 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
3003 SECURITY_CAP_AUDIT);
3004 break;
3005
3006 /* default case assumes that the command will go
3007 * to the file's ioctl() function.
3008 */
3009 default:
3010 error = file_has_perm(cred, file, FILE__IOCTL);
3011 }
3012 return error;
3013}
3014
3015static int default_noexec;
3016
3017static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3018{
3019 const struct cred *cred = current_cred();
3020 int rc = 0;
3021
3022 if (default_noexec &&
3023 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3024 /*
3025 * We are making executable an anonymous mapping or a
3026 * private file mapping that will also be writable.
3027 * This has an additional check.
3028 */
3029 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3030 if (rc)
3031 goto error;
3032 }
3033
3034 if (file) {
3035 /* read access is always possible with a mapping */
3036 u32 av = FILE__READ;
3037
3038 /* write access only matters if the mapping is shared */
3039 if (shared && (prot & PROT_WRITE))
3040 av |= FILE__WRITE;
3041
3042 if (prot & PROT_EXEC)
3043 av |= FILE__EXECUTE;
3044
3045 return file_has_perm(cred, file, av);
3046 }
3047
3048error:
3049 return rc;
3050}
3051
3052static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3053 unsigned long prot, unsigned long flags,
3054 unsigned long addr, unsigned long addr_only)
3055{
3056 int rc = 0;
3057 u32 sid = current_sid();
3058
3059 /*
3060 * notice that we are intentionally putting the SELinux check before
3061 * the secondary cap_file_mmap check. This is such a likely attempt
3062 * at bad behaviour/exploit that we always want to get the AVC, even
3063 * if DAC would have also denied the operation.
3064 */
3065 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3066 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3067 MEMPROTECT__MMAP_ZERO, NULL);
3068 if (rc)
3069 return rc;
3070 }
3071
3072 /* do DAC check on address space usage */
3073 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3074 if (rc || addr_only)
3075 return rc;
3076
3077 if (selinux_checkreqprot)
3078 prot = reqprot;
3079
3080 return file_map_prot_check(file, prot,
3081 (flags & MAP_TYPE) == MAP_SHARED);
3082}
3083
3084static int selinux_file_mprotect(struct vm_area_struct *vma,
3085 unsigned long reqprot,
3086 unsigned long prot)
3087{
3088 const struct cred *cred = current_cred();
3089
3090 if (selinux_checkreqprot)
3091 prot = reqprot;
3092
3093 if (default_noexec &&
3094 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3095 int rc = 0;
3096 if (vma->vm_start >= vma->vm_mm->start_brk &&
3097 vma->vm_end <= vma->vm_mm->brk) {
3098 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3099 } else if (!vma->vm_file &&
3100 vma->vm_start <= vma->vm_mm->start_stack &&
3101 vma->vm_end >= vma->vm_mm->start_stack) {
3102 rc = current_has_perm(current, PROCESS__EXECSTACK);
3103 } else if (vma->vm_file && vma->anon_vma) {
3104 /*
3105 * We are making executable a file mapping that has
3106 * had some COW done. Since pages might have been
3107 * written, check ability to execute the possibly
3108 * modified content. This typically should only
3109 * occur for text relocations.
3110 */
3111 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3112 }
3113 if (rc)
3114 return rc;
3115 }
3116
3117 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3118}
3119
3120static int selinux_file_lock(struct file *file, unsigned int cmd)
3121{
3122 const struct cred *cred = current_cred();
3123
3124 return file_has_perm(cred, file, FILE__LOCK);
3125}
3126
3127static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3128 unsigned long arg)
3129{
3130 const struct cred *cred = current_cred();
3131 int err = 0;
3132
3133 switch (cmd) {
3134 case F_SETFL:
3135 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3136 err = -EINVAL;
3137 break;
3138 }
3139
3140 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3141 err = file_has_perm(cred, file, FILE__WRITE);
3142 break;
3143 }
3144 /* fall through */
3145 case F_SETOWN:
3146 case F_SETSIG:
3147 case F_GETFL:
3148 case F_GETOWN:
3149 case F_GETSIG:
3150 /* Just check FD__USE permission */
3151 err = file_has_perm(cred, file, 0);
3152 break;
3153 case F_GETLK:
3154 case F_SETLK:
3155 case F_SETLKW:
3156#if BITS_PER_LONG == 32
3157 case F_GETLK64:
3158 case F_SETLK64:
3159 case F_SETLKW64:
3160#endif
3161 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3162 err = -EINVAL;
3163 break;
3164 }
3165 err = file_has_perm(cred, file, FILE__LOCK);
3166 break;
3167 }
3168
3169 return err;
3170}
3171
3172static int selinux_file_set_fowner(struct file *file)
3173{
3174 struct file_security_struct *fsec;
3175
3176 fsec = file->f_security;
3177 fsec->fown_sid = current_sid();
3178
3179 return 0;
3180}
3181
3182static int selinux_file_send_sigiotask(struct task_struct *tsk,
3183 struct fown_struct *fown, int signum)
3184{
3185 struct file *file;
3186 u32 sid = task_sid(tsk);
3187 u32 perm;
3188 struct file_security_struct *fsec;
3189
3190 /* struct fown_struct is never outside the context of a struct file */
3191 file = container_of(fown, struct file, f_owner);
3192
3193 fsec = file->f_security;
3194
3195 if (!signum)
3196 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3197 else
3198 perm = signal_to_av(signum);
3199
3200 return avc_has_perm(fsec->fown_sid, sid,
3201 SECCLASS_PROCESS, perm, NULL);
3202}
3203
3204static int selinux_file_receive(struct file *file)
3205{
3206 const struct cred *cred = current_cred();
3207
3208 return file_has_perm(cred, file, file_to_av(file));
3209}
3210
3211static int selinux_dentry_open(struct file *file, const struct cred *cred)
3212{
3213 struct file_security_struct *fsec;
3214 struct inode *inode;
3215 struct inode_security_struct *isec;
3216
3217 inode = file->f_path.dentry->d_inode;
3218 fsec = file->f_security;
3219 isec = inode->i_security;
3220 /*
3221 * Save inode label and policy sequence number
3222 * at open-time so that selinux_file_permission
3223 * can determine whether revalidation is necessary.
3224 * Task label is already saved in the file security
3225 * struct as its SID.
3226 */
3227 fsec->isid = isec->sid;
3228 fsec->pseqno = avc_policy_seqno();
3229 /*
3230 * Since the inode label or policy seqno may have changed
3231 * between the selinux_inode_permission check and the saving
3232 * of state above, recheck that access is still permitted.
3233 * Otherwise, access might never be revalidated against the
3234 * new inode label or new policy.
3235 * This check is not redundant - do not remove.
3236 */
3237 return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3238}
3239
3240/* task security operations */
3241
3242static int selinux_task_create(unsigned long clone_flags)
3243{
3244 return current_has_perm(current, PROCESS__FORK);
3245}
3246
3247/*
3248 * allocate the SELinux part of blank credentials
3249 */
3250static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3251{
3252 struct task_security_struct *tsec;
3253
3254 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3255 if (!tsec)
3256 return -ENOMEM;
3257
3258 cred->security = tsec;
3259 return 0;
3260}
3261
3262/*
3263 * detach and free the LSM part of a set of credentials
3264 */
3265static void selinux_cred_free(struct cred *cred)
3266{
3267 struct task_security_struct *tsec = cred->security;
3268
3269 /*
3270 * cred->security == NULL if security_cred_alloc_blank() or
3271 * security_prepare_creds() returned an error.
3272 */
3273 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3274 cred->security = (void *) 0x7UL;
3275 kfree(tsec);
3276}
3277
3278/*
3279 * prepare a new set of credentials for modification
3280 */
3281static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3282 gfp_t gfp)
3283{
3284 const struct task_security_struct *old_tsec;
3285 struct task_security_struct *tsec;
3286
3287 old_tsec = old->security;
3288
3289 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3290 if (!tsec)
3291 return -ENOMEM;
3292
3293 new->security = tsec;
3294 return 0;
3295}
3296
3297/*
3298 * transfer the SELinux data to a blank set of creds
3299 */
3300static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3301{
3302 const struct task_security_struct *old_tsec = old->security;
3303 struct task_security_struct *tsec = new->security;
3304
3305 *tsec = *old_tsec;
3306}
3307
3308/*
3309 * set the security data for a kernel service
3310 * - all the creation contexts are set to unlabelled
3311 */
3312static int selinux_kernel_act_as(struct cred *new, u32 secid)
3313{
3314 struct task_security_struct *tsec = new->security;
3315 u32 sid = current_sid();
3316 int ret;
3317
3318 ret = avc_has_perm(sid, secid,
3319 SECCLASS_KERNEL_SERVICE,
3320 KERNEL_SERVICE__USE_AS_OVERRIDE,
3321 NULL);
3322 if (ret == 0) {
3323 tsec->sid = secid;
3324 tsec->create_sid = 0;
3325 tsec->keycreate_sid = 0;
3326 tsec->sockcreate_sid = 0;
3327 }
3328 return ret;
3329}
3330
3331/*
3332 * set the file creation context in a security record to the same as the
3333 * objective context of the specified inode
3334 */
3335static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3336{
3337 struct inode_security_struct *isec = inode->i_security;
3338 struct task_security_struct *tsec = new->security;
3339 u32 sid = current_sid();
3340 int ret;
3341
3342 ret = avc_has_perm(sid, isec->sid,
3343 SECCLASS_KERNEL_SERVICE,
3344 KERNEL_SERVICE__CREATE_FILES_AS,
3345 NULL);
3346
3347 if (ret == 0)
3348 tsec->create_sid = isec->sid;
3349 return ret;
3350}
3351
3352static int selinux_kernel_module_request(char *kmod_name)
3353{
3354 u32 sid;
3355 struct common_audit_data ad;
3356
3357 sid = task_sid(current);
3358
3359 COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3360 ad.u.kmod_name = kmod_name;
3361
3362 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3363 SYSTEM__MODULE_REQUEST, &ad);
3364}
3365
3366static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3367{
3368 return current_has_perm(p, PROCESS__SETPGID);
3369}
3370
3371static int selinux_task_getpgid(struct task_struct *p)
3372{
3373 return current_has_perm(p, PROCESS__GETPGID);
3374}
3375
3376static int selinux_task_getsid(struct task_struct *p)
3377{
3378 return current_has_perm(p, PROCESS__GETSESSION);
3379}
3380
3381static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3382{
3383 *secid = task_sid(p);
3384}
3385
3386static int selinux_task_setnice(struct task_struct *p, int nice)
3387{
3388 int rc;
3389
3390 rc = cap_task_setnice(p, nice);
3391 if (rc)
3392 return rc;
3393
3394 return current_has_perm(p, PROCESS__SETSCHED);
3395}
3396
3397static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3398{
3399 int rc;
3400
3401 rc = cap_task_setioprio(p, ioprio);
3402 if (rc)
3403 return rc;
3404
3405 return current_has_perm(p, PROCESS__SETSCHED);
3406}
3407
3408static int selinux_task_getioprio(struct task_struct *p)
3409{
3410 return current_has_perm(p, PROCESS__GETSCHED);
3411}
3412
3413static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3414 struct rlimit *new_rlim)
3415{
3416 struct rlimit *old_rlim = p->signal->rlim + resource;
3417
3418 /* Control the ability to change the hard limit (whether
3419 lowering or raising it), so that the hard limit can
3420 later be used as a safe reset point for the soft limit
3421 upon context transitions. See selinux_bprm_committing_creds. */
3422 if (old_rlim->rlim_max != new_rlim->rlim_max)
3423 return current_has_perm(p, PROCESS__SETRLIMIT);
3424
3425 return 0;
3426}
3427
3428static int selinux_task_setscheduler(struct task_struct *p)
3429{
3430 int rc;
3431
3432 rc = cap_task_setscheduler(p);
3433 if (rc)
3434 return rc;
3435
3436 return current_has_perm(p, PROCESS__SETSCHED);
3437}
3438
3439static int selinux_task_getscheduler(struct task_struct *p)
3440{
3441 return current_has_perm(p, PROCESS__GETSCHED);
3442}
3443
3444static int selinux_task_movememory(struct task_struct *p)
3445{
3446 return current_has_perm(p, PROCESS__SETSCHED);
3447}
3448
3449static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3450 int sig, u32 secid)
3451{
3452 u32 perm;
3453 int rc;
3454
3455 if (!sig)
3456 perm = PROCESS__SIGNULL; /* null signal; existence test */
3457 else
3458 perm = signal_to_av(sig);
3459 if (secid)
3460 rc = avc_has_perm(secid, task_sid(p),
3461 SECCLASS_PROCESS, perm, NULL);
3462 else
3463 rc = current_has_perm(p, perm);
3464 return rc;
3465}
3466
3467static int selinux_task_wait(struct task_struct *p)
3468{
3469 return task_has_perm(p, current, PROCESS__SIGCHLD);
3470}
3471
3472static void selinux_task_to_inode(struct task_struct *p,
3473 struct inode *inode)
3474{
3475 struct inode_security_struct *isec = inode->i_security;
3476 u32 sid = task_sid(p);
3477
3478 isec->sid = sid;
3479 isec->initialized = 1;
3480}
3481
3482/* Returns error only if unable to parse addresses */
3483static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3484 struct common_audit_data *ad, u8 *proto)
3485{
3486 int offset, ihlen, ret = -EINVAL;
3487 struct iphdr _iph, *ih;
3488
3489 offset = skb_network_offset(skb);
3490 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3491 if (ih == NULL)
3492 goto out;
3493
3494 ihlen = ih->ihl * 4;
3495 if (ihlen < sizeof(_iph))
3496 goto out;
3497
3498 ad->u.net.v4info.saddr = ih->saddr;
3499 ad->u.net.v4info.daddr = ih->daddr;
3500 ret = 0;
3501
3502 if (proto)
3503 *proto = ih->protocol;
3504
3505 switch (ih->protocol) {
3506 case IPPROTO_TCP: {
3507 struct tcphdr _tcph, *th;
3508
3509 if (ntohs(ih->frag_off) & IP_OFFSET)
3510 break;
3511
3512 offset += ihlen;
3513 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3514 if (th == NULL)
3515 break;
3516
3517 ad->u.net.sport = th->source;
3518 ad->u.net.dport = th->dest;
3519 break;
3520 }
3521
3522 case IPPROTO_UDP: {
3523 struct udphdr _udph, *uh;
3524
3525 if (ntohs(ih->frag_off) & IP_OFFSET)
3526 break;
3527
3528 offset += ihlen;
3529 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3530 if (uh == NULL)
3531 break;
3532
3533 ad->u.net.sport = uh->source;
3534 ad->u.net.dport = uh->dest;
3535 break;
3536 }
3537
3538 case IPPROTO_DCCP: {
3539 struct dccp_hdr _dccph, *dh;
3540
3541 if (ntohs(ih->frag_off) & IP_OFFSET)
3542 break;
3543
3544 offset += ihlen;
3545 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3546 if (dh == NULL)
3547 break;
3548
3549 ad->u.net.sport = dh->dccph_sport;
3550 ad->u.net.dport = dh->dccph_dport;
3551 break;
3552 }
3553
3554 default:
3555 break;
3556 }
3557out:
3558 return ret;
3559}
3560
3561#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3562
3563/* Returns error only if unable to parse addresses */
3564static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3565 struct common_audit_data *ad, u8 *proto)
3566{
3567 u8 nexthdr;
3568 int ret = -EINVAL, offset;
3569 struct ipv6hdr _ipv6h, *ip6;
3570
3571 offset = skb_network_offset(skb);
3572 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3573 if (ip6 == NULL)
3574 goto out;
3575
3576 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3577 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3578 ret = 0;
3579
3580 nexthdr = ip6->nexthdr;
3581 offset += sizeof(_ipv6h);
3582 offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3583 if (offset < 0)
3584 goto out;
3585
3586 if (proto)
3587 *proto = nexthdr;
3588
3589 switch (nexthdr) {
3590 case IPPROTO_TCP: {
3591 struct tcphdr _tcph, *th;
3592
3593 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3594 if (th == NULL)
3595 break;
3596
3597 ad->u.net.sport = th->source;
3598 ad->u.net.dport = th->dest;
3599 break;
3600 }
3601
3602 case IPPROTO_UDP: {
3603 struct udphdr _udph, *uh;
3604
3605 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3606 if (uh == NULL)
3607 break;
3608
3609 ad->u.net.sport = uh->source;
3610 ad->u.net.dport = uh->dest;
3611 break;
3612 }
3613
3614 case IPPROTO_DCCP: {
3615 struct dccp_hdr _dccph, *dh;
3616
3617 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3618 if (dh == NULL)
3619 break;
3620
3621 ad->u.net.sport = dh->dccph_sport;
3622 ad->u.net.dport = dh->dccph_dport;
3623 break;
3624 }
3625
3626 /* includes fragments */
3627 default:
3628 break;
3629 }
3630out:
3631 return ret;
3632}
3633
3634#endif /* IPV6 */
3635
3636static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3637 char **_addrp, int src, u8 *proto)
3638{
3639 char *addrp;
3640 int ret;
3641
3642 switch (ad->u.net.family) {
3643 case PF_INET:
3644 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3645 if (ret)
3646 goto parse_error;
3647 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3648 &ad->u.net.v4info.daddr);
3649 goto okay;
3650
3651#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3652 case PF_INET6:
3653 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3654 if (ret)
3655 goto parse_error;
3656 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3657 &ad->u.net.v6info.daddr);
3658 goto okay;
3659#endif /* IPV6 */
3660 default:
3661 addrp = NULL;
3662 goto okay;
3663 }
3664
3665parse_error:
3666 printk(KERN_WARNING
3667 "SELinux: failure in selinux_parse_skb(),"
3668 " unable to parse packet\n");
3669 return ret;
3670
3671okay:
3672 if (_addrp)
3673 *_addrp = addrp;
3674 return 0;
3675}
3676
3677/**
3678 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3679 * @skb: the packet
3680 * @family: protocol family
3681 * @sid: the packet's peer label SID
3682 *
3683 * Description:
3684 * Check the various different forms of network peer labeling and determine
3685 * the peer label/SID for the packet; most of the magic actually occurs in
3686 * the security server function security_net_peersid_cmp(). The function
3687 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3688 * or -EACCES if @sid is invalid due to inconsistencies with the different
3689 * peer labels.
3690 *
3691 */
3692static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3693{
3694 int err;
3695 u32 xfrm_sid;
3696 u32 nlbl_sid;
3697 u32 nlbl_type;
3698
3699 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3700 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3701
3702 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3703 if (unlikely(err)) {
3704 printk(KERN_WARNING
3705 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3706 " unable to determine packet's peer label\n");
3707 return -EACCES;
3708 }
3709
3710 return 0;
3711}
3712
3713/* socket security operations */
3714
3715static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3716 u16 secclass, u32 *socksid)
3717{
3718 if (tsec->sockcreate_sid > SECSID_NULL) {
3719 *socksid = tsec->sockcreate_sid;
3720 return 0;
3721 }
3722
3723 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3724 socksid);
3725}
3726
3727static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3728{
3729 struct sk_security_struct *sksec = sk->sk_security;
3730 struct common_audit_data ad;
3731 u32 tsid = task_sid(task);
3732
3733 if (sksec->sid == SECINITSID_KERNEL)
3734 return 0;
3735
3736 COMMON_AUDIT_DATA_INIT(&ad, NET);
3737 ad.u.net.sk = sk;
3738
3739 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3740}
3741
3742static int selinux_socket_create(int family, int type,
3743 int protocol, int kern)
3744{
3745 const struct task_security_struct *tsec = current_security();
3746 u32 newsid;
3747 u16 secclass;
3748 int rc;
3749
3750 if (kern)
3751 return 0;
3752
3753 secclass = socket_type_to_security_class(family, type, protocol);
3754 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3755 if (rc)
3756 return rc;
3757
3758 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3759}
3760
3761static int selinux_socket_post_create(struct socket *sock, int family,
3762 int type, int protocol, int kern)
3763{
3764 const struct task_security_struct *tsec = current_security();
3765 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3766 struct sk_security_struct *sksec;
3767 int err = 0;
3768
3769 isec->sclass = socket_type_to_security_class(family, type, protocol);
3770
3771 if (kern)
3772 isec->sid = SECINITSID_KERNEL;
3773 else {
3774 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3775 if (err)
3776 return err;
3777 }
3778
3779 isec->initialized = 1;
3780
3781 if (sock->sk) {
3782 sksec = sock->sk->sk_security;
3783 sksec->sid = isec->sid;
3784 sksec->sclass = isec->sclass;
3785 err = selinux_netlbl_socket_post_create(sock->sk, family);
3786 }
3787
3788 return err;
3789}
3790
3791/* Range of port numbers used to automatically bind.
3792 Need to determine whether we should perform a name_bind
3793 permission check between the socket and the port number. */
3794
3795static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3796{
3797 struct sock *sk = sock->sk;
3798 u16 family;
3799 int err;
3800
3801 err = sock_has_perm(current, sk, SOCKET__BIND);
3802 if (err)
3803 goto out;
3804
3805 /*
3806 * If PF_INET or PF_INET6, check name_bind permission for the port.
3807 * Multiple address binding for SCTP is not supported yet: we just
3808 * check the first address now.
3809 */
3810 family = sk->sk_family;
3811 if (family == PF_INET || family == PF_INET6) {
3812 char *addrp;
3813 struct sk_security_struct *sksec = sk->sk_security;
3814 struct common_audit_data ad;
3815 struct sockaddr_in *addr4 = NULL;
3816 struct sockaddr_in6 *addr6 = NULL;
3817 unsigned short snum;
3818 u32 sid, node_perm;
3819
3820 if (family == PF_INET) {
3821 addr4 = (struct sockaddr_in *)address;
3822 snum = ntohs(addr4->sin_port);
3823 addrp = (char *)&addr4->sin_addr.s_addr;
3824 } else {
3825 addr6 = (struct sockaddr_in6 *)address;
3826 snum = ntohs(addr6->sin6_port);
3827 addrp = (char *)&addr6->sin6_addr.s6_addr;
3828 }
3829
3830 if (snum) {
3831 int low, high;
3832
3833 inet_get_local_port_range(&low, &high);
3834
3835 if (snum < max(PROT_SOCK, low) || snum > high) {
3836 err = sel_netport_sid(sk->sk_protocol,
3837 snum, &sid);
3838 if (err)
3839 goto out;
3840 COMMON_AUDIT_DATA_INIT(&ad, NET);
3841 ad.u.net.sport = htons(snum);
3842 ad.u.net.family = family;
3843 err = avc_has_perm(sksec->sid, sid,
3844 sksec->sclass,
3845 SOCKET__NAME_BIND, &ad);
3846 if (err)
3847 goto out;
3848 }
3849 }
3850
3851 switch (sksec->sclass) {
3852 case SECCLASS_TCP_SOCKET:
3853 node_perm = TCP_SOCKET__NODE_BIND;
3854 break;
3855
3856 case SECCLASS_UDP_SOCKET:
3857 node_perm = UDP_SOCKET__NODE_BIND;
3858 break;
3859
3860 case SECCLASS_DCCP_SOCKET:
3861 node_perm = DCCP_SOCKET__NODE_BIND;
3862 break;
3863
3864 default:
3865 node_perm = RAWIP_SOCKET__NODE_BIND;
3866 break;
3867 }
3868
3869 err = sel_netnode_sid(addrp, family, &sid);
3870 if (err)
3871 goto out;
3872
3873 COMMON_AUDIT_DATA_INIT(&ad, NET);
3874 ad.u.net.sport = htons(snum);
3875 ad.u.net.family = family;
3876
3877 if (family == PF_INET)
3878 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3879 else
3880 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3881
3882 err = avc_has_perm(sksec->sid, sid,
3883 sksec->sclass, node_perm, &ad);
3884 if (err)
3885 goto out;
3886 }
3887out:
3888 return err;
3889}
3890
3891static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3892{
3893 struct sock *sk = sock->sk;
3894 struct sk_security_struct *sksec = sk->sk_security;
3895 int err;
3896
3897 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3898 if (err)
3899 return err;
3900
3901 /*
3902 * If a TCP or DCCP socket, check name_connect permission for the port.
3903 */
3904 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3905 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3906 struct common_audit_data ad;
3907 struct sockaddr_in *addr4 = NULL;
3908 struct sockaddr_in6 *addr6 = NULL;
3909 unsigned short snum;
3910 u32 sid, perm;
3911
3912 if (sk->sk_family == PF_INET) {
3913 addr4 = (struct sockaddr_in *)address;
3914 if (addrlen < sizeof(struct sockaddr_in))
3915 return -EINVAL;
3916 snum = ntohs(addr4->sin_port);
3917 } else {
3918 addr6 = (struct sockaddr_in6 *)address;
3919 if (addrlen < SIN6_LEN_RFC2133)
3920 return -EINVAL;
3921 snum = ntohs(addr6->sin6_port);
3922 }
3923
3924 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3925 if (err)
3926 goto out;
3927
3928 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3929 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3930
3931 COMMON_AUDIT_DATA_INIT(&ad, NET);
3932 ad.u.net.dport = htons(snum);
3933 ad.u.net.family = sk->sk_family;
3934 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3935 if (err)
3936 goto out;
3937 }
3938
3939 err = selinux_netlbl_socket_connect(sk, address);
3940
3941out:
3942 return err;
3943}
3944
3945static int selinux_socket_listen(struct socket *sock, int backlog)
3946{
3947 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3948}
3949
3950static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3951{
3952 int err;
3953 struct inode_security_struct *isec;
3954 struct inode_security_struct *newisec;
3955
3956 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3957 if (err)
3958 return err;
3959
3960 newisec = SOCK_INODE(newsock)->i_security;
3961
3962 isec = SOCK_INODE(sock)->i_security;
3963 newisec->sclass = isec->sclass;
3964 newisec->sid = isec->sid;
3965 newisec->initialized = 1;
3966
3967 return 0;
3968}
3969
3970static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3971 int size)
3972{
3973 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3974}
3975
3976static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3977 int size, int flags)
3978{
3979 return sock_has_perm(current, sock->sk, SOCKET__READ);
3980}
3981
3982static int selinux_socket_getsockname(struct socket *sock)
3983{
3984 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3985}
3986
3987static int selinux_socket_getpeername(struct socket *sock)
3988{
3989 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3990}
3991
3992static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3993{
3994 int err;
3995
3996 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3997 if (err)
3998 return err;
3999
4000 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4001}
4002
4003static int selinux_socket_getsockopt(struct socket *sock, int level,
4004 int optname)
4005{
4006 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4007}
4008
4009static int selinux_socket_shutdown(struct socket *sock, int how)
4010{
4011 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4012}
4013
4014static int selinux_socket_unix_stream_connect(struct sock *sock,
4015 struct sock *other,
4016 struct sock *newsk)
4017{
4018 struct sk_security_struct *sksec_sock = sock->sk_security;
4019 struct sk_security_struct *sksec_other = other->sk_security;
4020 struct sk_security_struct *sksec_new = newsk->sk_security;
4021 struct common_audit_data ad;
4022 int err;
4023
4024 COMMON_AUDIT_DATA_INIT(&ad, NET);
4025 ad.u.net.sk = other;
4026
4027 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4028 sksec_other->sclass,
4029 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4030 if (err)
4031 return err;
4032
4033 /* server child socket */
4034 sksec_new->peer_sid = sksec_sock->sid;
4035 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4036 &sksec_new->sid);
4037 if (err)
4038 return err;
4039
4040 /* connecting socket */
4041 sksec_sock->peer_sid = sksec_new->sid;
4042
4043 return 0;
4044}
4045
4046static int selinux_socket_unix_may_send(struct socket *sock,
4047 struct socket *other)
4048{
4049 struct sk_security_struct *ssec = sock->sk->sk_security;
4050 struct sk_security_struct *osec = other->sk->sk_security;
4051 struct common_audit_data ad;
4052
4053 COMMON_AUDIT_DATA_INIT(&ad, NET);
4054 ad.u.net.sk = other->sk;
4055
4056 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4057 &ad);
4058}
4059
4060static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4061 u32 peer_sid,
4062 struct common_audit_data *ad)
4063{
4064 int err;
4065 u32 if_sid;
4066 u32 node_sid;
4067
4068 err = sel_netif_sid(ifindex, &if_sid);
4069 if (err)
4070 return err;
4071 err = avc_has_perm(peer_sid, if_sid,
4072 SECCLASS_NETIF, NETIF__INGRESS, ad);
4073 if (err)
4074 return err;
4075
4076 err = sel_netnode_sid(addrp, family, &node_sid);
4077 if (err)
4078 return err;
4079 return avc_has_perm(peer_sid, node_sid,
4080 SECCLASS_NODE, NODE__RECVFROM, ad);
4081}
4082
4083static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4084 u16 family)
4085{
4086 int err = 0;
4087 struct sk_security_struct *sksec = sk->sk_security;
4088 u32 sk_sid = sksec->sid;
4089 struct common_audit_data ad;
4090 char *addrp;
4091
4092 COMMON_AUDIT_DATA_INIT(&ad, NET);
4093 ad.u.net.netif = skb->skb_iif;
4094 ad.u.net.family = family;
4095 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4096 if (err)
4097 return err;
4098
4099 if (selinux_secmark_enabled()) {
4100 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4101 PACKET__RECV, &ad);
4102 if (err)
4103 return err;
4104 }
4105
4106 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4107 if (err)
4108 return err;
4109 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4110
4111 return err;
4112}
4113
4114static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4115{
4116 int err;
4117 struct sk_security_struct *sksec = sk->sk_security;
4118 u16 family = sk->sk_family;
4119 u32 sk_sid = sksec->sid;
4120 struct common_audit_data ad;
4121 char *addrp;
4122 u8 secmark_active;
4123 u8 peerlbl_active;
4124
4125 if (family != PF_INET && family != PF_INET6)
4126 return 0;
4127
4128 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4129 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4130 family = PF_INET;
4131
4132 /* If any sort of compatibility mode is enabled then handoff processing
4133 * to the selinux_sock_rcv_skb_compat() function to deal with the
4134 * special handling. We do this in an attempt to keep this function
4135 * as fast and as clean as possible. */
4136 if (!selinux_policycap_netpeer)
4137 return selinux_sock_rcv_skb_compat(sk, skb, family);
4138
4139 secmark_active = selinux_secmark_enabled();
4140 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4141 if (!secmark_active && !peerlbl_active)
4142 return 0;
4143
4144 COMMON_AUDIT_DATA_INIT(&ad, NET);
4145 ad.u.net.netif = skb->skb_iif;
4146 ad.u.net.family = family;
4147 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4148 if (err)
4149 return err;
4150
4151 if (peerlbl_active) {
4152 u32 peer_sid;
4153
4154 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4155 if (err)
4156 return err;
4157 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4158 peer_sid, &ad);
4159 if (err) {
4160 selinux_netlbl_err(skb, err, 0);
4161 return err;
4162 }
4163 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4164 PEER__RECV, &ad);
4165 if (err)
4166 selinux_netlbl_err(skb, err, 0);
4167 }
4168
4169 if (secmark_active) {
4170 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4171 PACKET__RECV, &ad);
4172 if (err)
4173 return err;
4174 }
4175
4176 return err;
4177}
4178
4179static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4180 int __user *optlen, unsigned len)
4181{
4182 int err = 0;
4183 char *scontext;
4184 u32 scontext_len;
4185 struct sk_security_struct *sksec = sock->sk->sk_security;
4186 u32 peer_sid = SECSID_NULL;
4187
4188 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4189 sksec->sclass == SECCLASS_TCP_SOCKET)
4190 peer_sid = sksec->peer_sid;
4191 if (peer_sid == SECSID_NULL)
4192 return -ENOPROTOOPT;
4193
4194 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4195 if (err)
4196 return err;
4197
4198 if (scontext_len > len) {
4199 err = -ERANGE;
4200 goto out_len;
4201 }
4202
4203 if (copy_to_user(optval, scontext, scontext_len))
4204 err = -EFAULT;
4205
4206out_len:
4207 if (put_user(scontext_len, optlen))
4208 err = -EFAULT;
4209 kfree(scontext);
4210 return err;
4211}
4212
4213static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4214{
4215 u32 peer_secid = SECSID_NULL;
4216 u16 family;
4217
4218 if (skb && skb->protocol == htons(ETH_P_IP))
4219 family = PF_INET;
4220 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4221 family = PF_INET6;
4222 else if (sock)
4223 family = sock->sk->sk_family;
4224 else
4225 goto out;
4226
4227 if (sock && family == PF_UNIX)
4228 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4229 else if (skb)
4230 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4231
4232out:
4233 *secid = peer_secid;
4234 if (peer_secid == SECSID_NULL)
4235 return -EINVAL;
4236 return 0;
4237}
4238
4239static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4240{
4241 struct sk_security_struct *sksec;
4242
4243 sksec = kzalloc(sizeof(*sksec), priority);
4244 if (!sksec)
4245 return -ENOMEM;
4246
4247 sksec->peer_sid = SECINITSID_UNLABELED;
4248 sksec->sid = SECINITSID_UNLABELED;
4249 selinux_netlbl_sk_security_reset(sksec);
4250 sk->sk_security = sksec;
4251
4252 return 0;
4253}
4254
4255static void selinux_sk_free_security(struct sock *sk)
4256{
4257 struct sk_security_struct *sksec = sk->sk_security;
4258
4259 sk->sk_security = NULL;
4260 selinux_netlbl_sk_security_free(sksec);
4261 kfree(sksec);
4262}
4263
4264static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4265{
4266 struct sk_security_struct *sksec = sk->sk_security;
4267 struct sk_security_struct *newsksec = newsk->sk_security;
4268
4269 newsksec->sid = sksec->sid;
4270 newsksec->peer_sid = sksec->peer_sid;
4271 newsksec->sclass = sksec->sclass;
4272
4273 selinux_netlbl_sk_security_reset(newsksec);
4274}
4275
4276static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4277{
4278 if (!sk)
4279 *secid = SECINITSID_ANY_SOCKET;
4280 else {
4281 struct sk_security_struct *sksec = sk->sk_security;
4282
4283 *secid = sksec->sid;
4284 }
4285}
4286
4287static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4288{
4289 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4290 struct sk_security_struct *sksec = sk->sk_security;
4291
4292 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4293 sk->sk_family == PF_UNIX)
4294 isec->sid = sksec->sid;
4295 sksec->sclass = isec->sclass;
4296}
4297
4298static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4299 struct request_sock *req)
4300{
4301 struct sk_security_struct *sksec = sk->sk_security;
4302 int err;
4303 u16 family = sk->sk_family;
4304 u32 newsid;
4305 u32 peersid;
4306
4307 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4308 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4309 family = PF_INET;
4310
4311 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4312 if (err)
4313 return err;
4314 if (peersid == SECSID_NULL) {
4315 req->secid = sksec->sid;
4316 req->peer_secid = SECSID_NULL;
4317 } else {
4318 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4319 if (err)
4320 return err;
4321 req->secid = newsid;
4322 req->peer_secid = peersid;
4323 }
4324
4325 return selinux_netlbl_inet_conn_request(req, family);
4326}
4327
4328static void selinux_inet_csk_clone(struct sock *newsk,
4329 const struct request_sock *req)
4330{
4331 struct sk_security_struct *newsksec = newsk->sk_security;
4332
4333 newsksec->sid = req->secid;
4334 newsksec->peer_sid = req->peer_secid;
4335 /* NOTE: Ideally, we should also get the isec->sid for the
4336 new socket in sync, but we don't have the isec available yet.
4337 So we will wait until sock_graft to do it, by which
4338 time it will have been created and available. */
4339
4340 /* We don't need to take any sort of lock here as we are the only
4341 * thread with access to newsksec */
4342 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4343}
4344
4345static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4346{
4347 u16 family = sk->sk_family;
4348 struct sk_security_struct *sksec = sk->sk_security;
4349
4350 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4351 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4352 family = PF_INET;
4353
4354 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4355}
4356
4357static int selinux_secmark_relabel_packet(u32 sid)
4358{
4359 const struct task_security_struct *__tsec;
4360 u32 tsid;
4361
4362 __tsec = current_security();
4363 tsid = __tsec->sid;
4364
4365 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4366}
4367
4368static void selinux_secmark_refcount_inc(void)
4369{
4370 atomic_inc(&selinux_secmark_refcount);
4371}
4372
4373static void selinux_secmark_refcount_dec(void)
4374{
4375 atomic_dec(&selinux_secmark_refcount);
4376}
4377
4378static void selinux_req_classify_flow(const struct request_sock *req,
4379 struct flowi *fl)
4380{
4381 fl->flowi_secid = req->secid;
4382}
4383
4384static int selinux_tun_dev_create(void)
4385{
4386 u32 sid = current_sid();
4387
4388 /* we aren't taking into account the "sockcreate" SID since the socket
4389 * that is being created here is not a socket in the traditional sense,
4390 * instead it is a private sock, accessible only to the kernel, and
4391 * representing a wide range of network traffic spanning multiple
4392 * connections unlike traditional sockets - check the TUN driver to
4393 * get a better understanding of why this socket is special */
4394
4395 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4396 NULL);
4397}
4398
4399static void selinux_tun_dev_post_create(struct sock *sk)
4400{
4401 struct sk_security_struct *sksec = sk->sk_security;
4402
4403 /* we don't currently perform any NetLabel based labeling here and it
4404 * isn't clear that we would want to do so anyway; while we could apply
4405 * labeling without the support of the TUN user the resulting labeled
4406 * traffic from the other end of the connection would almost certainly
4407 * cause confusion to the TUN user that had no idea network labeling
4408 * protocols were being used */
4409
4410 /* see the comments in selinux_tun_dev_create() about why we don't use
4411 * the sockcreate SID here */
4412
4413 sksec->sid = current_sid();
4414 sksec->sclass = SECCLASS_TUN_SOCKET;
4415}
4416
4417static int selinux_tun_dev_attach(struct sock *sk)
4418{
4419 struct sk_security_struct *sksec = sk->sk_security;
4420 u32 sid = current_sid();
4421 int err;
4422
4423 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4424 TUN_SOCKET__RELABELFROM, NULL);
4425 if (err)
4426 return err;
4427 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4428 TUN_SOCKET__RELABELTO, NULL);
4429 if (err)
4430 return err;
4431
4432 sksec->sid = sid;
4433
4434 return 0;
4435}
4436
4437static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4438{
4439 int err = 0;
4440 u32 perm;
4441 struct nlmsghdr *nlh;
4442 struct sk_security_struct *sksec = sk->sk_security;
4443
4444 if (skb->len < NLMSG_SPACE(0)) {
4445 err = -EINVAL;
4446 goto out;
4447 }
4448 nlh = nlmsg_hdr(skb);
4449
4450 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4451 if (err) {
4452 if (err == -EINVAL) {
4453 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4454 "SELinux: unrecognized netlink message"
4455 " type=%hu for sclass=%hu\n",
4456 nlh->nlmsg_type, sksec->sclass);
4457 if (!selinux_enforcing || security_get_allow_unknown())
4458 err = 0;
4459 }
4460
4461 /* Ignore */
4462 if (err == -ENOENT)
4463 err = 0;
4464 goto out;
4465 }
4466
4467 err = sock_has_perm(current, sk, perm);
4468out:
4469 return err;
4470}
4471
4472#ifdef CONFIG_NETFILTER
4473
4474static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4475 u16 family)
4476{
4477 int err;
4478 char *addrp;
4479 u32 peer_sid;
4480 struct common_audit_data ad;
4481 u8 secmark_active;
4482 u8 netlbl_active;
4483 u8 peerlbl_active;
4484
4485 if (!selinux_policycap_netpeer)
4486 return NF_ACCEPT;
4487
4488 secmark_active = selinux_secmark_enabled();
4489 netlbl_active = netlbl_enabled();
4490 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4491 if (!secmark_active && !peerlbl_active)
4492 return NF_ACCEPT;
4493
4494 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4495 return NF_DROP;
4496
4497 COMMON_AUDIT_DATA_INIT(&ad, NET);
4498 ad.u.net.netif = ifindex;
4499 ad.u.net.family = family;
4500 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4501 return NF_DROP;
4502
4503 if (peerlbl_active) {
4504 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4505 peer_sid, &ad);
4506 if (err) {
4507 selinux_netlbl_err(skb, err, 1);
4508 return NF_DROP;
4509 }
4510 }
4511
4512 if (secmark_active)
4513 if (avc_has_perm(peer_sid, skb->secmark,
4514 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4515 return NF_DROP;
4516
4517 if (netlbl_active)
4518 /* we do this in the FORWARD path and not the POST_ROUTING
4519 * path because we want to make sure we apply the necessary
4520 * labeling before IPsec is applied so we can leverage AH
4521 * protection */
4522 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4523 return NF_DROP;
4524
4525 return NF_ACCEPT;
4526}
4527
4528static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4529 struct sk_buff *skb,
4530 const struct net_device *in,
4531 const struct net_device *out,
4532 int (*okfn)(struct sk_buff *))
4533{
4534 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4535}
4536
4537#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4538static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4539 struct sk_buff *skb,
4540 const struct net_device *in,
4541 const struct net_device *out,
4542 int (*okfn)(struct sk_buff *))
4543{
4544 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4545}
4546#endif /* IPV6 */
4547
4548static unsigned int selinux_ip_output(struct sk_buff *skb,
4549 u16 family)
4550{
4551 u32 sid;
4552
4553 if (!netlbl_enabled())
4554 return NF_ACCEPT;
4555
4556 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4557 * because we want to make sure we apply the necessary labeling
4558 * before IPsec is applied so we can leverage AH protection */
4559 if (skb->sk) {
4560 struct sk_security_struct *sksec = skb->sk->sk_security;
4561 sid = sksec->sid;
4562 } else
4563 sid = SECINITSID_KERNEL;
4564 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4565 return NF_DROP;
4566
4567 return NF_ACCEPT;
4568}
4569
4570static unsigned int selinux_ipv4_output(unsigned int hooknum,
4571 struct sk_buff *skb,
4572 const struct net_device *in,
4573 const struct net_device *out,
4574 int (*okfn)(struct sk_buff *))
4575{
4576 return selinux_ip_output(skb, PF_INET);
4577}
4578
4579static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4580 int ifindex,
4581 u16 family)
4582{
4583 struct sock *sk = skb->sk;
4584 struct sk_security_struct *sksec;
4585 struct common_audit_data ad;
4586 char *addrp;
4587 u8 proto;
4588
4589 if (sk == NULL)
4590 return NF_ACCEPT;
4591 sksec = sk->sk_security;
4592
4593 COMMON_AUDIT_DATA_INIT(&ad, NET);
4594 ad.u.net.netif = ifindex;
4595 ad.u.net.family = family;
4596 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4597 return NF_DROP;
4598
4599 if (selinux_secmark_enabled())
4600 if (avc_has_perm(sksec->sid, skb->secmark,
4601 SECCLASS_PACKET, PACKET__SEND, &ad))
4602 return NF_DROP_ERR(-ECONNREFUSED);
4603
4604 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4605 return NF_DROP_ERR(-ECONNREFUSED);
4606
4607 return NF_ACCEPT;
4608}
4609
4610static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4611 u16 family)
4612{
4613 u32 secmark_perm;
4614 u32 peer_sid;
4615 struct sock *sk;
4616 struct common_audit_data ad;
4617 char *addrp;
4618 u8 secmark_active;
4619 u8 peerlbl_active;
4620
4621 /* If any sort of compatibility mode is enabled then handoff processing
4622 * to the selinux_ip_postroute_compat() function to deal with the
4623 * special handling. We do this in an attempt to keep this function
4624 * as fast and as clean as possible. */
4625 if (!selinux_policycap_netpeer)
4626 return selinux_ip_postroute_compat(skb, ifindex, family);
4627#ifdef CONFIG_XFRM
4628 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4629 * packet transformation so allow the packet to pass without any checks
4630 * since we'll have another chance to perform access control checks
4631 * when the packet is on it's final way out.
4632 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4633 * is NULL, in this case go ahead and apply access control. */
4634 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4635 return NF_ACCEPT;
4636#endif
4637 secmark_active = selinux_secmark_enabled();
4638 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4639 if (!secmark_active && !peerlbl_active)
4640 return NF_ACCEPT;
4641
4642 /* if the packet is being forwarded then get the peer label from the
4643 * packet itself; otherwise check to see if it is from a local
4644 * application or the kernel, if from an application get the peer label
4645 * from the sending socket, otherwise use the kernel's sid */
4646 sk = skb->sk;
4647 if (sk == NULL) {
4648 if (skb->skb_iif) {
4649 secmark_perm = PACKET__FORWARD_OUT;
4650 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4651 return NF_DROP;
4652 } else {
4653 secmark_perm = PACKET__SEND;
4654 peer_sid = SECINITSID_KERNEL;
4655 }
4656 } else {
4657 struct sk_security_struct *sksec = sk->sk_security;
4658 peer_sid = sksec->sid;
4659 secmark_perm = PACKET__SEND;
4660 }
4661
4662 COMMON_AUDIT_DATA_INIT(&ad, NET);
4663 ad.u.net.netif = ifindex;
4664 ad.u.net.family = family;
4665 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4666 return NF_DROP;
4667
4668 if (secmark_active)
4669 if (avc_has_perm(peer_sid, skb->secmark,
4670 SECCLASS_PACKET, secmark_perm, &ad))
4671 return NF_DROP_ERR(-ECONNREFUSED);
4672
4673 if (peerlbl_active) {
4674 u32 if_sid;
4675 u32 node_sid;
4676
4677 if (sel_netif_sid(ifindex, &if_sid))
4678 return NF_DROP;
4679 if (avc_has_perm(peer_sid, if_sid,
4680 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4681 return NF_DROP_ERR(-ECONNREFUSED);
4682
4683 if (sel_netnode_sid(addrp, family, &node_sid))
4684 return NF_DROP;
4685 if (avc_has_perm(peer_sid, node_sid,
4686 SECCLASS_NODE, NODE__SENDTO, &ad))
4687 return NF_DROP_ERR(-ECONNREFUSED);
4688 }
4689
4690 return NF_ACCEPT;
4691}
4692
4693static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4694 struct sk_buff *skb,
4695 const struct net_device *in,
4696 const struct net_device *out,
4697 int (*okfn)(struct sk_buff *))
4698{
4699 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4700}
4701
4702#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4703static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4704 struct sk_buff *skb,
4705 const struct net_device *in,
4706 const struct net_device *out,
4707 int (*okfn)(struct sk_buff *))
4708{
4709 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4710}
4711#endif /* IPV6 */
4712
4713#endif /* CONFIG_NETFILTER */
4714
4715static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4716{
4717 int err;
4718
4719 err = cap_netlink_send(sk, skb);
4720 if (err)
4721 return err;
4722
4723 return selinux_nlmsg_perm(sk, skb);
4724}
4725
4726static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4727{
4728 int err;
4729 struct common_audit_data ad;
4730 u32 sid;
4731
4732 err = cap_netlink_recv(skb, capability);
4733 if (err)
4734 return err;
4735
4736 COMMON_AUDIT_DATA_INIT(&ad, CAP);
4737 ad.u.cap = capability;
4738
4739 security_task_getsecid(current, &sid);
4740 return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
4741 CAP_TO_MASK(capability), &ad);
4742}
4743
4744static int ipc_alloc_security(struct task_struct *task,
4745 struct kern_ipc_perm *perm,
4746 u16 sclass)
4747{
4748 struct ipc_security_struct *isec;
4749 u32 sid;
4750
4751 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4752 if (!isec)
4753 return -ENOMEM;
4754
4755 sid = task_sid(task);
4756 isec->sclass = sclass;
4757 isec->sid = sid;
4758 perm->security = isec;
4759
4760 return 0;
4761}
4762
4763static void ipc_free_security(struct kern_ipc_perm *perm)
4764{
4765 struct ipc_security_struct *isec = perm->security;
4766 perm->security = NULL;
4767 kfree(isec);
4768}
4769
4770static int msg_msg_alloc_security(struct msg_msg *msg)
4771{
4772 struct msg_security_struct *msec;
4773
4774 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4775 if (!msec)
4776 return -ENOMEM;
4777
4778 msec->sid = SECINITSID_UNLABELED;
4779 msg->security = msec;
4780
4781 return 0;
4782}
4783
4784static void msg_msg_free_security(struct msg_msg *msg)
4785{
4786 struct msg_security_struct *msec = msg->security;
4787
4788 msg->security = NULL;
4789 kfree(msec);
4790}
4791
4792static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4793 u32 perms)
4794{
4795 struct ipc_security_struct *isec;
4796 struct common_audit_data ad;
4797 u32 sid = current_sid();
4798
4799 isec = ipc_perms->security;
4800
4801 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4802 ad.u.ipc_id = ipc_perms->key;
4803
4804 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4805}
4806
4807static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4808{
4809 return msg_msg_alloc_security(msg);
4810}
4811
4812static void selinux_msg_msg_free_security(struct msg_msg *msg)
4813{
4814 msg_msg_free_security(msg);
4815}
4816
4817/* message queue security operations */
4818static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4819{
4820 struct ipc_security_struct *isec;
4821 struct common_audit_data ad;
4822 u32 sid = current_sid();
4823 int rc;
4824
4825 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4826 if (rc)
4827 return rc;
4828
4829 isec = msq->q_perm.security;
4830
4831 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4832 ad.u.ipc_id = msq->q_perm.key;
4833
4834 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4835 MSGQ__CREATE, &ad);
4836 if (rc) {
4837 ipc_free_security(&msq->q_perm);
4838 return rc;
4839 }
4840 return 0;
4841}
4842
4843static void selinux_msg_queue_free_security(struct msg_queue *msq)
4844{
4845 ipc_free_security(&msq->q_perm);
4846}
4847
4848static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4849{
4850 struct ipc_security_struct *isec;
4851 struct common_audit_data ad;
4852 u32 sid = current_sid();
4853
4854 isec = msq->q_perm.security;
4855
4856 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4857 ad.u.ipc_id = msq->q_perm.key;
4858
4859 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4860 MSGQ__ASSOCIATE, &ad);
4861}
4862
4863static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4864{
4865 int err;
4866 int perms;
4867
4868 switch (cmd) {
4869 case IPC_INFO:
4870 case MSG_INFO:
4871 /* No specific object, just general system-wide information. */
4872 return task_has_system(current, SYSTEM__IPC_INFO);
4873 case IPC_STAT:
4874 case MSG_STAT:
4875 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4876 break;
4877 case IPC_SET:
4878 perms = MSGQ__SETATTR;
4879 break;
4880 case IPC_RMID:
4881 perms = MSGQ__DESTROY;
4882 break;
4883 default:
4884 return 0;
4885 }
4886
4887 err = ipc_has_perm(&msq->q_perm, perms);
4888 return err;
4889}
4890
4891static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4892{
4893 struct ipc_security_struct *isec;
4894 struct msg_security_struct *msec;
4895 struct common_audit_data ad;
4896 u32 sid = current_sid();
4897 int rc;
4898
4899 isec = msq->q_perm.security;
4900 msec = msg->security;
4901
4902 /*
4903 * First time through, need to assign label to the message
4904 */
4905 if (msec->sid == SECINITSID_UNLABELED) {
4906 /*
4907 * Compute new sid based on current process and
4908 * message queue this message will be stored in
4909 */
4910 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4911 NULL, &msec->sid);
4912 if (rc)
4913 return rc;
4914 }
4915
4916 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4917 ad.u.ipc_id = msq->q_perm.key;
4918
4919 /* Can this process write to the queue? */
4920 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4921 MSGQ__WRITE, &ad);
4922 if (!rc)
4923 /* Can this process send the message */
4924 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4925 MSG__SEND, &ad);
4926 if (!rc)
4927 /* Can the message be put in the queue? */
4928 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4929 MSGQ__ENQUEUE, &ad);
4930
4931 return rc;
4932}
4933
4934static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4935 struct task_struct *target,
4936 long type, int mode)
4937{
4938 struct ipc_security_struct *isec;
4939 struct msg_security_struct *msec;
4940 struct common_audit_data ad;
4941 u32 sid = task_sid(target);
4942 int rc;
4943
4944 isec = msq->q_perm.security;
4945 msec = msg->security;
4946
4947 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4948 ad.u.ipc_id = msq->q_perm.key;
4949
4950 rc = avc_has_perm(sid, isec->sid,
4951 SECCLASS_MSGQ, MSGQ__READ, &ad);
4952 if (!rc)
4953 rc = avc_has_perm(sid, msec->sid,
4954 SECCLASS_MSG, MSG__RECEIVE, &ad);
4955 return rc;
4956}
4957
4958/* Shared Memory security operations */
4959static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4960{
4961 struct ipc_security_struct *isec;
4962 struct common_audit_data ad;
4963 u32 sid = current_sid();
4964 int rc;
4965
4966 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4967 if (rc)
4968 return rc;
4969
4970 isec = shp->shm_perm.security;
4971
4972 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4973 ad.u.ipc_id = shp->shm_perm.key;
4974
4975 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4976 SHM__CREATE, &ad);
4977 if (rc) {
4978 ipc_free_security(&shp->shm_perm);
4979 return rc;
4980 }
4981 return 0;
4982}
4983
4984static void selinux_shm_free_security(struct shmid_kernel *shp)
4985{
4986 ipc_free_security(&shp->shm_perm);
4987}
4988
4989static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4990{
4991 struct ipc_security_struct *isec;
4992 struct common_audit_data ad;
4993 u32 sid = current_sid();
4994
4995 isec = shp->shm_perm.security;
4996
4997 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4998 ad.u.ipc_id = shp->shm_perm.key;
4999
5000 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5001 SHM__ASSOCIATE, &ad);
5002}
5003
5004/* Note, at this point, shp is locked down */
5005static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5006{
5007 int perms;
5008 int err;
5009
5010 switch (cmd) {
5011 case IPC_INFO:
5012 case SHM_INFO:
5013 /* No specific object, just general system-wide information. */
5014 return task_has_system(current, SYSTEM__IPC_INFO);
5015 case IPC_STAT:
5016 case SHM_STAT:
5017 perms = SHM__GETATTR | SHM__ASSOCIATE;
5018 break;
5019 case IPC_SET:
5020 perms = SHM__SETATTR;
5021 break;
5022 case SHM_LOCK:
5023 case SHM_UNLOCK:
5024 perms = SHM__LOCK;
5025 break;
5026 case IPC_RMID:
5027 perms = SHM__DESTROY;
5028 break;
5029 default:
5030 return 0;
5031 }
5032
5033 err = ipc_has_perm(&shp->shm_perm, perms);
5034 return err;
5035}
5036
5037static int selinux_shm_shmat(struct shmid_kernel *shp,
5038 char __user *shmaddr, int shmflg)
5039{
5040 u32 perms;
5041
5042 if (shmflg & SHM_RDONLY)
5043 perms = SHM__READ;
5044 else
5045 perms = SHM__READ | SHM__WRITE;
5046
5047 return ipc_has_perm(&shp->shm_perm, perms);
5048}
5049
5050/* Semaphore security operations */
5051static int selinux_sem_alloc_security(struct sem_array *sma)
5052{
5053 struct ipc_security_struct *isec;
5054 struct common_audit_data ad;
5055 u32 sid = current_sid();
5056 int rc;
5057
5058 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5059 if (rc)
5060 return rc;
5061
5062 isec = sma->sem_perm.security;
5063
5064 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5065 ad.u.ipc_id = sma->sem_perm.key;
5066
5067 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5068 SEM__CREATE, &ad);
5069 if (rc) {
5070 ipc_free_security(&sma->sem_perm);
5071 return rc;
5072 }
5073 return 0;
5074}
5075
5076static void selinux_sem_free_security(struct sem_array *sma)
5077{
5078 ipc_free_security(&sma->sem_perm);
5079}
5080
5081static int selinux_sem_associate(struct sem_array *sma, int semflg)
5082{
5083 struct ipc_security_struct *isec;
5084 struct common_audit_data ad;
5085 u32 sid = current_sid();
5086
5087 isec = sma->sem_perm.security;
5088
5089 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5090 ad.u.ipc_id = sma->sem_perm.key;
5091
5092 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5093 SEM__ASSOCIATE, &ad);
5094}
5095
5096/* Note, at this point, sma is locked down */
5097static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5098{
5099 int err;
5100 u32 perms;
5101
5102 switch (cmd) {
5103 case IPC_INFO:
5104 case SEM_INFO:
5105 /* No specific object, just general system-wide information. */
5106 return task_has_system(current, SYSTEM__IPC_INFO);
5107 case GETPID:
5108 case GETNCNT:
5109 case GETZCNT:
5110 perms = SEM__GETATTR;
5111 break;
5112 case GETVAL:
5113 case GETALL:
5114 perms = SEM__READ;
5115 break;
5116 case SETVAL:
5117 case SETALL:
5118 perms = SEM__WRITE;
5119 break;
5120 case IPC_RMID:
5121 perms = SEM__DESTROY;
5122 break;
5123 case IPC_SET:
5124 perms = SEM__SETATTR;
5125 break;
5126 case IPC_STAT:
5127 case SEM_STAT:
5128 perms = SEM__GETATTR | SEM__ASSOCIATE;
5129 break;
5130 default:
5131 return 0;
5132 }
5133
5134 err = ipc_has_perm(&sma->sem_perm, perms);
5135 return err;
5136}
5137
5138static int selinux_sem_semop(struct sem_array *sma,
5139 struct sembuf *sops, unsigned nsops, int alter)
5140{
5141 u32 perms;
5142
5143 if (alter)
5144 perms = SEM__READ | SEM__WRITE;
5145 else
5146 perms = SEM__READ;
5147
5148 return ipc_has_perm(&sma->sem_perm, perms);
5149}
5150
5151static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5152{
5153 u32 av = 0;
5154
5155 av = 0;
5156 if (flag & S_IRUGO)
5157 av |= IPC__UNIX_READ;
5158 if (flag & S_IWUGO)
5159 av |= IPC__UNIX_WRITE;
5160
5161 if (av == 0)
5162 return 0;
5163
5164 return ipc_has_perm(ipcp, av);
5165}
5166
5167static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5168{
5169 struct ipc_security_struct *isec = ipcp->security;
5170 *secid = isec->sid;
5171}
5172
5173static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5174{
5175 if (inode)
5176 inode_doinit_with_dentry(inode, dentry);
5177}
5178
5179static int selinux_getprocattr(struct task_struct *p,
5180 char *name, char **value)
5181{
5182 const struct task_security_struct *__tsec;
5183 u32 sid;
5184 int error;
5185 unsigned len;
5186
5187 if (current != p) {
5188 error = current_has_perm(p, PROCESS__GETATTR);
5189 if (error)
5190 return error;
5191 }
5192
5193 rcu_read_lock();
5194 __tsec = __task_cred(p)->security;
5195
5196 if (!strcmp(name, "current"))
5197 sid = __tsec->sid;
5198 else if (!strcmp(name, "prev"))
5199 sid = __tsec->osid;
5200 else if (!strcmp(name, "exec"))
5201 sid = __tsec->exec_sid;
5202 else if (!strcmp(name, "fscreate"))
5203 sid = __tsec->create_sid;
5204 else if (!strcmp(name, "keycreate"))
5205 sid = __tsec->keycreate_sid;
5206 else if (!strcmp(name, "sockcreate"))
5207 sid = __tsec->sockcreate_sid;
5208 else
5209 goto invalid;
5210 rcu_read_unlock();
5211
5212 if (!sid)
5213 return 0;
5214
5215 error = security_sid_to_context(sid, value, &len);
5216 if (error)
5217 return error;
5218 return len;
5219
5220invalid:
5221 rcu_read_unlock();
5222 return -EINVAL;
5223}
5224
5225static int selinux_setprocattr(struct task_struct *p,
5226 char *name, void *value, size_t size)
5227{
5228 struct task_security_struct *tsec;
5229 struct task_struct *tracer;
5230 struct cred *new;
5231 u32 sid = 0, ptsid;
5232 int error;
5233 char *str = value;
5234
5235 if (current != p) {
5236 /* SELinux only allows a process to change its own
5237 security attributes. */
5238 return -EACCES;
5239 }
5240
5241 /*
5242 * Basic control over ability to set these attributes at all.
5243 * current == p, but we'll pass them separately in case the
5244 * above restriction is ever removed.
5245 */
5246 if (!strcmp(name, "exec"))
5247 error = current_has_perm(p, PROCESS__SETEXEC);
5248 else if (!strcmp(name, "fscreate"))
5249 error = current_has_perm(p, PROCESS__SETFSCREATE);
5250 else if (!strcmp(name, "keycreate"))
5251 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5252 else if (!strcmp(name, "sockcreate"))
5253 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5254 else if (!strcmp(name, "current"))
5255 error = current_has_perm(p, PROCESS__SETCURRENT);
5256 else
5257 error = -EINVAL;
5258 if (error)
5259 return error;
5260
5261 /* Obtain a SID for the context, if one was specified. */
5262 if (size && str[1] && str[1] != '\n') {
5263 if (str[size-1] == '\n') {
5264 str[size-1] = 0;
5265 size--;
5266 }
5267 error = security_context_to_sid(value, size, &sid);
5268 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5269 if (!capable(CAP_MAC_ADMIN))
5270 return error;
5271 error = security_context_to_sid_force(value, size,
5272 &sid);
5273 }
5274 if (error)
5275 return error;
5276 }
5277
5278 new = prepare_creds();
5279 if (!new)
5280 return -ENOMEM;
5281
5282 /* Permission checking based on the specified context is
5283 performed during the actual operation (execve,
5284 open/mkdir/...), when we know the full context of the
5285 operation. See selinux_bprm_set_creds for the execve
5286 checks and may_create for the file creation checks. The
5287 operation will then fail if the context is not permitted. */
5288 tsec = new->security;
5289 if (!strcmp(name, "exec")) {
5290 tsec->exec_sid = sid;
5291 } else if (!strcmp(name, "fscreate")) {
5292 tsec->create_sid = sid;
5293 } else if (!strcmp(name, "keycreate")) {
5294 error = may_create_key(sid, p);
5295 if (error)
5296 goto abort_change;
5297 tsec->keycreate_sid = sid;
5298 } else if (!strcmp(name, "sockcreate")) {
5299 tsec->sockcreate_sid = sid;
5300 } else if (!strcmp(name, "current")) {
5301 error = -EINVAL;
5302 if (sid == 0)
5303 goto abort_change;
5304
5305 /* Only allow single threaded processes to change context */
5306 error = -EPERM;
5307 if (!current_is_single_threaded()) {
5308 error = security_bounded_transition(tsec->sid, sid);
5309 if (error)
5310 goto abort_change;
5311 }
5312
5313 /* Check permissions for the transition. */
5314 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5315 PROCESS__DYNTRANSITION, NULL);
5316 if (error)
5317 goto abort_change;
5318
5319 /* Check for ptracing, and update the task SID if ok.
5320 Otherwise, leave SID unchanged and fail. */
5321 ptsid = 0;
5322 task_lock(p);
5323 tracer = ptrace_parent(p);
5324 if (tracer)
5325 ptsid = task_sid(tracer);
5326 task_unlock(p);
5327
5328 if (tracer) {
5329 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5330 PROCESS__PTRACE, NULL);
5331 if (error)
5332 goto abort_change;
5333 }
5334
5335 tsec->sid = sid;
5336 } else {
5337 error = -EINVAL;
5338 goto abort_change;
5339 }
5340
5341 commit_creds(new);
5342 return size;
5343
5344abort_change:
5345 abort_creds(new);
5346 return error;
5347}
5348
5349static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5350{
5351 return security_sid_to_context(secid, secdata, seclen);
5352}
5353
5354static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5355{
5356 return security_context_to_sid(secdata, seclen, secid);
5357}
5358
5359static void selinux_release_secctx(char *secdata, u32 seclen)
5360{
5361 kfree(secdata);
5362}
5363
5364/*
5365 * called with inode->i_mutex locked
5366 */
5367static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5368{
5369 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5370}
5371
5372/*
5373 * called with inode->i_mutex locked
5374 */
5375static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5376{
5377 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5378}
5379
5380static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5381{
5382 int len = 0;
5383 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5384 ctx, true);
5385 if (len < 0)
5386 return len;
5387 *ctxlen = len;
5388 return 0;
5389}
5390#ifdef CONFIG_KEYS
5391
5392static int selinux_key_alloc(struct key *k, const struct cred *cred,
5393 unsigned long flags)
5394{
5395 const struct task_security_struct *tsec;
5396 struct key_security_struct *ksec;
5397
5398 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5399 if (!ksec)
5400 return -ENOMEM;
5401
5402 tsec = cred->security;
5403 if (tsec->keycreate_sid)
5404 ksec->sid = tsec->keycreate_sid;
5405 else
5406 ksec->sid = tsec->sid;
5407
5408 k->security = ksec;
5409 return 0;
5410}
5411
5412static void selinux_key_free(struct key *k)
5413{
5414 struct key_security_struct *ksec = k->security;
5415
5416 k->security = NULL;
5417 kfree(ksec);
5418}
5419
5420static int selinux_key_permission(key_ref_t key_ref,
5421 const struct cred *cred,
5422 key_perm_t perm)
5423{
5424 struct key *key;
5425 struct key_security_struct *ksec;
5426 u32 sid;
5427
5428 /* if no specific permissions are requested, we skip the
5429 permission check. No serious, additional covert channels
5430 appear to be created. */
5431 if (perm == 0)
5432 return 0;
5433
5434 sid = cred_sid(cred);
5435
5436 key = key_ref_to_ptr(key_ref);
5437 ksec = key->security;
5438
5439 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5440}
5441
5442static int selinux_key_getsecurity(struct key *key, char **_buffer)
5443{
5444 struct key_security_struct *ksec = key->security;
5445 char *context = NULL;
5446 unsigned len;
5447 int rc;
5448
5449 rc = security_sid_to_context(ksec->sid, &context, &len);
5450 if (!rc)
5451 rc = len;
5452 *_buffer = context;
5453 return rc;
5454}
5455
5456#endif
5457
5458static struct security_operations selinux_ops = {
5459 .name = "selinux",
5460
5461 .ptrace_access_check = selinux_ptrace_access_check,
5462 .ptrace_traceme = selinux_ptrace_traceme,
5463 .capget = selinux_capget,
5464 .capset = selinux_capset,
5465 .capable = selinux_capable,
5466 .quotactl = selinux_quotactl,
5467 .quota_on = selinux_quota_on,
5468 .syslog = selinux_syslog,
5469 .vm_enough_memory = selinux_vm_enough_memory,
5470
5471 .netlink_send = selinux_netlink_send,
5472 .netlink_recv = selinux_netlink_recv,
5473
5474 .bprm_set_creds = selinux_bprm_set_creds,
5475 .bprm_committing_creds = selinux_bprm_committing_creds,
5476 .bprm_committed_creds = selinux_bprm_committed_creds,
5477 .bprm_secureexec = selinux_bprm_secureexec,
5478
5479 .sb_alloc_security = selinux_sb_alloc_security,
5480 .sb_free_security = selinux_sb_free_security,
5481 .sb_copy_data = selinux_sb_copy_data,
5482 .sb_remount = selinux_sb_remount,
5483 .sb_kern_mount = selinux_sb_kern_mount,
5484 .sb_show_options = selinux_sb_show_options,
5485 .sb_statfs = selinux_sb_statfs,
5486 .sb_mount = selinux_mount,
5487 .sb_umount = selinux_umount,
5488 .sb_set_mnt_opts = selinux_set_mnt_opts,
5489 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5490 .sb_parse_opts_str = selinux_parse_opts_str,
5491
5492
5493 .inode_alloc_security = selinux_inode_alloc_security,
5494 .inode_free_security = selinux_inode_free_security,
5495 .inode_init_security = selinux_inode_init_security,
5496 .inode_create = selinux_inode_create,
5497 .inode_link = selinux_inode_link,
5498 .inode_unlink = selinux_inode_unlink,
5499 .inode_symlink = selinux_inode_symlink,
5500 .inode_mkdir = selinux_inode_mkdir,
5501 .inode_rmdir = selinux_inode_rmdir,
5502 .inode_mknod = selinux_inode_mknod,
5503 .inode_rename = selinux_inode_rename,
5504 .inode_readlink = selinux_inode_readlink,
5505 .inode_follow_link = selinux_inode_follow_link,
5506 .inode_permission = selinux_inode_permission,
5507 .inode_setattr = selinux_inode_setattr,
5508 .inode_getattr = selinux_inode_getattr,
5509 .inode_setxattr = selinux_inode_setxattr,
5510 .inode_post_setxattr = selinux_inode_post_setxattr,
5511 .inode_getxattr = selinux_inode_getxattr,
5512 .inode_listxattr = selinux_inode_listxattr,
5513 .inode_removexattr = selinux_inode_removexattr,
5514 .inode_getsecurity = selinux_inode_getsecurity,
5515 .inode_setsecurity = selinux_inode_setsecurity,
5516 .inode_listsecurity = selinux_inode_listsecurity,
5517 .inode_getsecid = selinux_inode_getsecid,
5518
5519 .file_permission = selinux_file_permission,
5520 .file_alloc_security = selinux_file_alloc_security,
5521 .file_free_security = selinux_file_free_security,
5522 .file_ioctl = selinux_file_ioctl,
5523 .file_mmap = selinux_file_mmap,
5524 .file_mprotect = selinux_file_mprotect,
5525 .file_lock = selinux_file_lock,
5526 .file_fcntl = selinux_file_fcntl,
5527 .file_set_fowner = selinux_file_set_fowner,
5528 .file_send_sigiotask = selinux_file_send_sigiotask,
5529 .file_receive = selinux_file_receive,
5530
5531 .dentry_open = selinux_dentry_open,
5532
5533 .task_create = selinux_task_create,
5534 .cred_alloc_blank = selinux_cred_alloc_blank,
5535 .cred_free = selinux_cred_free,
5536 .cred_prepare = selinux_cred_prepare,
5537 .cred_transfer = selinux_cred_transfer,
5538 .kernel_act_as = selinux_kernel_act_as,
5539 .kernel_create_files_as = selinux_kernel_create_files_as,
5540 .kernel_module_request = selinux_kernel_module_request,
5541 .task_setpgid = selinux_task_setpgid,
5542 .task_getpgid = selinux_task_getpgid,
5543 .task_getsid = selinux_task_getsid,
5544 .task_getsecid = selinux_task_getsecid,
5545 .task_setnice = selinux_task_setnice,
5546 .task_setioprio = selinux_task_setioprio,
5547 .task_getioprio = selinux_task_getioprio,
5548 .task_setrlimit = selinux_task_setrlimit,
5549 .task_setscheduler = selinux_task_setscheduler,
5550 .task_getscheduler = selinux_task_getscheduler,
5551 .task_movememory = selinux_task_movememory,
5552 .task_kill = selinux_task_kill,
5553 .task_wait = selinux_task_wait,
5554 .task_to_inode = selinux_task_to_inode,
5555
5556 .ipc_permission = selinux_ipc_permission,
5557 .ipc_getsecid = selinux_ipc_getsecid,
5558
5559 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5560 .msg_msg_free_security = selinux_msg_msg_free_security,
5561
5562 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5563 .msg_queue_free_security = selinux_msg_queue_free_security,
5564 .msg_queue_associate = selinux_msg_queue_associate,
5565 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5566 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5567 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5568
5569 .shm_alloc_security = selinux_shm_alloc_security,
5570 .shm_free_security = selinux_shm_free_security,
5571 .shm_associate = selinux_shm_associate,
5572 .shm_shmctl = selinux_shm_shmctl,
5573 .shm_shmat = selinux_shm_shmat,
5574
5575 .sem_alloc_security = selinux_sem_alloc_security,
5576 .sem_free_security = selinux_sem_free_security,
5577 .sem_associate = selinux_sem_associate,
5578 .sem_semctl = selinux_sem_semctl,
5579 .sem_semop = selinux_sem_semop,
5580
5581 .d_instantiate = selinux_d_instantiate,
5582
5583 .getprocattr = selinux_getprocattr,
5584 .setprocattr = selinux_setprocattr,
5585
5586 .secid_to_secctx = selinux_secid_to_secctx,
5587 .secctx_to_secid = selinux_secctx_to_secid,
5588 .release_secctx = selinux_release_secctx,
5589 .inode_notifysecctx = selinux_inode_notifysecctx,
5590 .inode_setsecctx = selinux_inode_setsecctx,
5591 .inode_getsecctx = selinux_inode_getsecctx,
5592
5593 .unix_stream_connect = selinux_socket_unix_stream_connect,
5594 .unix_may_send = selinux_socket_unix_may_send,
5595
5596 .socket_create = selinux_socket_create,
5597 .socket_post_create = selinux_socket_post_create,
5598 .socket_bind = selinux_socket_bind,
5599 .socket_connect = selinux_socket_connect,
5600 .socket_listen = selinux_socket_listen,
5601 .socket_accept = selinux_socket_accept,
5602 .socket_sendmsg = selinux_socket_sendmsg,
5603 .socket_recvmsg = selinux_socket_recvmsg,
5604 .socket_getsockname = selinux_socket_getsockname,
5605 .socket_getpeername = selinux_socket_getpeername,
5606 .socket_getsockopt = selinux_socket_getsockopt,
5607 .socket_setsockopt = selinux_socket_setsockopt,
5608 .socket_shutdown = selinux_socket_shutdown,
5609 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5610 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5611 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5612 .sk_alloc_security = selinux_sk_alloc_security,
5613 .sk_free_security = selinux_sk_free_security,
5614 .sk_clone_security = selinux_sk_clone_security,
5615 .sk_getsecid = selinux_sk_getsecid,
5616 .sock_graft = selinux_sock_graft,
5617 .inet_conn_request = selinux_inet_conn_request,
5618 .inet_csk_clone = selinux_inet_csk_clone,
5619 .inet_conn_established = selinux_inet_conn_established,
5620 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5621 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5622 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5623 .req_classify_flow = selinux_req_classify_flow,
5624 .tun_dev_create = selinux_tun_dev_create,
5625 .tun_dev_post_create = selinux_tun_dev_post_create,
5626 .tun_dev_attach = selinux_tun_dev_attach,
5627
5628#ifdef CONFIG_SECURITY_NETWORK_XFRM
5629 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5630 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5631 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5632 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5633 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5634 .xfrm_state_free_security = selinux_xfrm_state_free,
5635 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5636 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5637 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5638 .xfrm_decode_session = selinux_xfrm_decode_session,
5639#endif
5640
5641#ifdef CONFIG_KEYS
5642 .key_alloc = selinux_key_alloc,
5643 .key_free = selinux_key_free,
5644 .key_permission = selinux_key_permission,
5645 .key_getsecurity = selinux_key_getsecurity,
5646#endif
5647
5648#ifdef CONFIG_AUDIT
5649 .audit_rule_init = selinux_audit_rule_init,
5650 .audit_rule_known = selinux_audit_rule_known,
5651 .audit_rule_match = selinux_audit_rule_match,
5652 .audit_rule_free = selinux_audit_rule_free,
5653#endif
5654};
5655
5656static __init int selinux_init(void)
5657{
5658 if (!security_module_enable(&selinux_ops)) {
5659 selinux_enabled = 0;
5660 return 0;
5661 }
5662
5663 if (!selinux_enabled) {
5664 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5665 return 0;
5666 }
5667
5668 printk(KERN_INFO "SELinux: Initializing.\n");
5669
5670 /* Set the security state for the initial task. */
5671 cred_init_security();
5672
5673 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5674
5675 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5676 sizeof(struct inode_security_struct),
5677 0, SLAB_PANIC, NULL);
5678 avc_init();
5679
5680 if (register_security(&selinux_ops))
5681 panic("SELinux: Unable to register with kernel.\n");
5682
5683 if (selinux_enforcing)
5684 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5685 else
5686 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5687
5688 return 0;
5689}
5690
5691static void delayed_superblock_init(struct super_block *sb, void *unused)
5692{
5693 superblock_doinit(sb, NULL);
5694}
5695
5696void selinux_complete_init(void)
5697{
5698 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5699
5700 /* Set up any superblocks initialized prior to the policy load. */
5701 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5702 iterate_supers(delayed_superblock_init, NULL);
5703}
5704
5705/* SELinux requires early initialization in order to label
5706 all processes and objects when they are created. */
5707security_initcall(selinux_init);
5708
5709#if defined(CONFIG_NETFILTER)
5710
5711static struct nf_hook_ops selinux_ipv4_ops[] = {
5712 {
5713 .hook = selinux_ipv4_postroute,
5714 .owner = THIS_MODULE,
5715 .pf = PF_INET,
5716 .hooknum = NF_INET_POST_ROUTING,
5717 .priority = NF_IP_PRI_SELINUX_LAST,
5718 },
5719 {
5720 .hook = selinux_ipv4_forward,
5721 .owner = THIS_MODULE,
5722 .pf = PF_INET,
5723 .hooknum = NF_INET_FORWARD,
5724 .priority = NF_IP_PRI_SELINUX_FIRST,
5725 },
5726 {
5727 .hook = selinux_ipv4_output,
5728 .owner = THIS_MODULE,
5729 .pf = PF_INET,
5730 .hooknum = NF_INET_LOCAL_OUT,
5731 .priority = NF_IP_PRI_SELINUX_FIRST,
5732 }
5733};
5734
5735#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5736
5737static struct nf_hook_ops selinux_ipv6_ops[] = {
5738 {
5739 .hook = selinux_ipv6_postroute,
5740 .owner = THIS_MODULE,
5741 .pf = PF_INET6,
5742 .hooknum = NF_INET_POST_ROUTING,
5743 .priority = NF_IP6_PRI_SELINUX_LAST,
5744 },
5745 {
5746 .hook = selinux_ipv6_forward,
5747 .owner = THIS_MODULE,
5748 .pf = PF_INET6,
5749 .hooknum = NF_INET_FORWARD,
5750 .priority = NF_IP6_PRI_SELINUX_FIRST,
5751 }
5752};
5753
5754#endif /* IPV6 */
5755
5756static int __init selinux_nf_ip_init(void)
5757{
5758 int err = 0;
5759
5760 if (!selinux_enabled)
5761 goto out;
5762
5763 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5764
5765 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5766 if (err)
5767 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5768
5769#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5770 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5771 if (err)
5772 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5773#endif /* IPV6 */
5774
5775out:
5776 return err;
5777}
5778
5779__initcall(selinux_nf_ip_init);
5780
5781#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5782static void selinux_nf_ip_exit(void)
5783{
5784 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5785
5786 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5787#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5788 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5789#endif /* IPV6 */
5790}
5791#endif
5792
5793#else /* CONFIG_NETFILTER */
5794
5795#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5796#define selinux_nf_ip_exit()
5797#endif
5798
5799#endif /* CONFIG_NETFILTER */
5800
5801#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5802static int selinux_disabled;
5803
5804int selinux_disable(void)
5805{
5806 extern void exit_sel_fs(void);
5807
5808 if (ss_initialized) {
5809 /* Not permitted after initial policy load. */
5810 return -EINVAL;
5811 }
5812
5813 if (selinux_disabled) {
5814 /* Only do this once. */
5815 return -EINVAL;
5816 }
5817
5818 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5819
5820 selinux_disabled = 1;
5821 selinux_enabled = 0;
5822
5823 reset_security_ops();
5824
5825 /* Try to destroy the avc node cache */
5826 avc_disable();
5827
5828 /* Unregister netfilter hooks. */
5829 selinux_nf_ip_exit();
5830
5831 /* Unregister selinuxfs. */
5832 exit_sel_fs();
5833
5834 return 0;
5835}
5836#endif