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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Security-Enhanced Linux (SELinux) security module
4 *
5 * This file contains the SELinux hook function implementations.
6 *
7 * Authors: Stephen Smalley, <stephen.smalley.work@gmail.com>
8 * Chris Vance, <cvance@nai.com>
9 * Wayne Salamon, <wsalamon@nai.com>
10 * James Morris <jmorris@redhat.com>
11 *
12 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
13 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
14 * Eric Paris <eparis@redhat.com>
15 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
16 * <dgoeddel@trustedcs.com>
17 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
18 * Paul Moore <paul@paul-moore.com>
19 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
20 * Yuichi Nakamura <ynakam@hitachisoft.jp>
21 * Copyright (C) 2016 Mellanox Technologies
22 */
23
24#include <linux/init.h>
25#include <linux/kd.h>
26#include <linux/kernel.h>
27#include <linux/kernel_read_file.h>
28#include <linux/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 <uapi/linux/shm.h>
89#include <linux/bpf.h>
90#include <linux/kernfs.h>
91#include <linux/stringhash.h> /* for hashlen_string() */
92#include <uapi/linux/mount.h>
93#include <linux/fsnotify.h>
94#include <linux/fanotify.h>
95#include <linux/io_uring/cmd.h>
96#include <uapi/linux/lsm.h>
97
98#include "avc.h"
99#include "objsec.h"
100#include "netif.h"
101#include "netnode.h"
102#include "netport.h"
103#include "ibpkey.h"
104#include "xfrm.h"
105#include "netlabel.h"
106#include "audit.h"
107#include "avc_ss.h"
108
109#define SELINUX_INODE_INIT_XATTRS 1
110
111struct selinux_state selinux_state;
112
113/* SECMARK reference count */
114static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
115
116#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
117static int selinux_enforcing_boot __initdata;
118
119static int __init enforcing_setup(char *str)
120{
121 unsigned long enforcing;
122 if (!kstrtoul(str, 0, &enforcing))
123 selinux_enforcing_boot = enforcing ? 1 : 0;
124 return 1;
125}
126__setup("enforcing=", enforcing_setup);
127#else
128#define selinux_enforcing_boot 1
129#endif
130
131int selinux_enabled_boot __initdata = 1;
132#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
133static int __init selinux_enabled_setup(char *str)
134{
135 unsigned long enabled;
136 if (!kstrtoul(str, 0, &enabled))
137 selinux_enabled_boot = enabled ? 1 : 0;
138 return 1;
139}
140__setup("selinux=", selinux_enabled_setup);
141#endif
142
143static int __init checkreqprot_setup(char *str)
144{
145 unsigned long checkreqprot;
146
147 if (!kstrtoul(str, 0, &checkreqprot)) {
148 if (checkreqprot)
149 pr_err("SELinux: checkreqprot set to 1 via kernel parameter. This is no longer supported.\n");
150 }
151 return 1;
152}
153__setup("checkreqprot=", checkreqprot_setup);
154
155/**
156 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
157 *
158 * Description:
159 * This function checks the SECMARK reference counter to see if any SECMARK
160 * targets are currently configured, if the reference counter is greater than
161 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
162 * enabled, false (0) if SECMARK is disabled. If the always_check_network
163 * policy capability is enabled, SECMARK is always considered enabled.
164 *
165 */
166static int selinux_secmark_enabled(void)
167{
168 return (selinux_policycap_alwaysnetwork() ||
169 atomic_read(&selinux_secmark_refcount));
170}
171
172/**
173 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
174 *
175 * Description:
176 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true
177 * (1) if any are enabled or false (0) if neither are enabled. If the
178 * always_check_network policy capability is enabled, peer labeling
179 * is always considered enabled.
180 *
181 */
182static int selinux_peerlbl_enabled(void)
183{
184 return (selinux_policycap_alwaysnetwork() ||
185 netlbl_enabled() || selinux_xfrm_enabled());
186}
187
188static int selinux_netcache_avc_callback(u32 event)
189{
190 if (event == AVC_CALLBACK_RESET) {
191 sel_netif_flush();
192 sel_netnode_flush();
193 sel_netport_flush();
194 synchronize_net();
195 }
196 return 0;
197}
198
199static int selinux_lsm_notifier_avc_callback(u32 event)
200{
201 if (event == AVC_CALLBACK_RESET) {
202 sel_ib_pkey_flush();
203 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
204 }
205
206 return 0;
207}
208
209/*
210 * initialise the security for the init task
211 */
212static void cred_init_security(void)
213{
214 struct task_security_struct *tsec;
215
216 tsec = selinux_cred(unrcu_pointer(current->real_cred));
217 tsec->osid = tsec->sid = SECINITSID_KERNEL;
218}
219
220/*
221 * get the security ID of a set of credentials
222 */
223static inline u32 cred_sid(const struct cred *cred)
224{
225 const struct task_security_struct *tsec;
226
227 tsec = selinux_cred(cred);
228 return tsec->sid;
229}
230
231static void __ad_net_init(struct common_audit_data *ad,
232 struct lsm_network_audit *net,
233 int ifindex, struct sock *sk, u16 family)
234{
235 ad->type = LSM_AUDIT_DATA_NET;
236 ad->u.net = net;
237 net->netif = ifindex;
238 net->sk = sk;
239 net->family = family;
240}
241
242static void ad_net_init_from_sk(struct common_audit_data *ad,
243 struct lsm_network_audit *net,
244 struct sock *sk)
245{
246 __ad_net_init(ad, net, 0, sk, 0);
247}
248
249static void ad_net_init_from_iif(struct common_audit_data *ad,
250 struct lsm_network_audit *net,
251 int ifindex, u16 family)
252{
253 __ad_net_init(ad, net, ifindex, NULL, family);
254}
255
256/*
257 * get the objective security ID of a task
258 */
259static inline u32 task_sid_obj(const struct task_struct *task)
260{
261 u32 sid;
262
263 rcu_read_lock();
264 sid = cred_sid(__task_cred(task));
265 rcu_read_unlock();
266 return sid;
267}
268
269static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
270
271/*
272 * Try reloading inode security labels that have been marked as invalid. The
273 * @may_sleep parameter indicates when sleeping and thus reloading labels is
274 * allowed; when set to false, returns -ECHILD when the label is
275 * invalid. The @dentry parameter should be set to a dentry of the inode.
276 */
277static int __inode_security_revalidate(struct inode *inode,
278 struct dentry *dentry,
279 bool may_sleep)
280{
281 struct inode_security_struct *isec = selinux_inode(inode);
282
283 might_sleep_if(may_sleep);
284
285 /*
286 * The check of isec->initialized below is racy but
287 * inode_doinit_with_dentry() will recheck with
288 * isec->lock held.
289 */
290 if (selinux_initialized() &&
291 data_race(isec->initialized != LABEL_INITIALIZED)) {
292 if (!may_sleep)
293 return -ECHILD;
294
295 /*
296 * Try reloading the inode security label. This will fail if
297 * @opt_dentry is NULL and no dentry for this inode can be
298 * found; in that case, continue using the old label.
299 */
300 inode_doinit_with_dentry(inode, dentry);
301 }
302 return 0;
303}
304
305static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
306{
307 return selinux_inode(inode);
308}
309
310static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
311{
312 int error;
313
314 error = __inode_security_revalidate(inode, NULL, !rcu);
315 if (error)
316 return ERR_PTR(error);
317 return selinux_inode(inode);
318}
319
320/*
321 * Get the security label of an inode.
322 */
323static struct inode_security_struct *inode_security(struct inode *inode)
324{
325 __inode_security_revalidate(inode, NULL, true);
326 return selinux_inode(inode);
327}
328
329static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
330{
331 struct inode *inode = d_backing_inode(dentry);
332
333 return selinux_inode(inode);
334}
335
336/*
337 * Get the security label of a dentry's backing inode.
338 */
339static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
340{
341 struct inode *inode = d_backing_inode(dentry);
342
343 __inode_security_revalidate(inode, dentry, true);
344 return selinux_inode(inode);
345}
346
347static void inode_free_security(struct inode *inode)
348{
349 struct inode_security_struct *isec = selinux_inode(inode);
350 struct superblock_security_struct *sbsec;
351
352 if (!isec)
353 return;
354 sbsec = selinux_superblock(inode->i_sb);
355 /*
356 * As not all inode security structures are in a list, we check for
357 * empty list outside of the lock to make sure that we won't waste
358 * time taking a lock doing nothing.
359 *
360 * The list_del_init() function can be safely called more than once.
361 * It should not be possible for this function to be called with
362 * concurrent list_add(), but for better safety against future changes
363 * in the code, we use list_empty_careful() here.
364 */
365 if (!list_empty_careful(&isec->list)) {
366 spin_lock(&sbsec->isec_lock);
367 list_del_init(&isec->list);
368 spin_unlock(&sbsec->isec_lock);
369 }
370}
371
372struct selinux_mnt_opts {
373 u32 fscontext_sid;
374 u32 context_sid;
375 u32 rootcontext_sid;
376 u32 defcontext_sid;
377};
378
379static void selinux_free_mnt_opts(void *mnt_opts)
380{
381 kfree(mnt_opts);
382}
383
384enum {
385 Opt_error = -1,
386 Opt_context = 0,
387 Opt_defcontext = 1,
388 Opt_fscontext = 2,
389 Opt_rootcontext = 3,
390 Opt_seclabel = 4,
391};
392
393#define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
394static const struct {
395 const char *name;
396 int len;
397 int opt;
398 bool has_arg;
399} tokens[] = {
400 A(context, true),
401 A(fscontext, true),
402 A(defcontext, true),
403 A(rootcontext, true),
404 A(seclabel, false),
405};
406#undef A
407
408static int match_opt_prefix(char *s, int l, char **arg)
409{
410 int i;
411
412 for (i = 0; i < ARRAY_SIZE(tokens); i++) {
413 size_t len = tokens[i].len;
414 if (len > l || memcmp(s, tokens[i].name, len))
415 continue;
416 if (tokens[i].has_arg) {
417 if (len == l || s[len] != '=')
418 continue;
419 *arg = s + len + 1;
420 } else if (len != l)
421 continue;
422 return tokens[i].opt;
423 }
424 return Opt_error;
425}
426
427#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
428
429static int may_context_mount_sb_relabel(u32 sid,
430 struct superblock_security_struct *sbsec,
431 const struct cred *cred)
432{
433 const struct task_security_struct *tsec = selinux_cred(cred);
434 int rc;
435
436 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
437 FILESYSTEM__RELABELFROM, NULL);
438 if (rc)
439 return rc;
440
441 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
442 FILESYSTEM__RELABELTO, NULL);
443 return rc;
444}
445
446static int may_context_mount_inode_relabel(u32 sid,
447 struct superblock_security_struct *sbsec,
448 const struct cred *cred)
449{
450 const struct task_security_struct *tsec = selinux_cred(cred);
451 int rc;
452 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
453 FILESYSTEM__RELABELFROM, NULL);
454 if (rc)
455 return rc;
456
457 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
458 FILESYSTEM__ASSOCIATE, NULL);
459 return rc;
460}
461
462static int selinux_is_genfs_special_handling(struct super_block *sb)
463{
464 /* Special handling. Genfs but also in-core setxattr handler */
465 return !strcmp(sb->s_type->name, "sysfs") ||
466 !strcmp(sb->s_type->name, "pstore") ||
467 !strcmp(sb->s_type->name, "debugfs") ||
468 !strcmp(sb->s_type->name, "tracefs") ||
469 !strcmp(sb->s_type->name, "rootfs") ||
470 (selinux_policycap_cgroupseclabel() &&
471 (!strcmp(sb->s_type->name, "cgroup") ||
472 !strcmp(sb->s_type->name, "cgroup2")));
473}
474
475static int selinux_is_sblabel_mnt(struct super_block *sb)
476{
477 struct superblock_security_struct *sbsec = selinux_superblock(sb);
478
479 /*
480 * IMPORTANT: Double-check logic in this function when adding a new
481 * SECURITY_FS_USE_* definition!
482 */
483 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
484
485 switch (sbsec->behavior) {
486 case SECURITY_FS_USE_XATTR:
487 case SECURITY_FS_USE_TRANS:
488 case SECURITY_FS_USE_TASK:
489 case SECURITY_FS_USE_NATIVE:
490 return 1;
491
492 case SECURITY_FS_USE_GENFS:
493 return selinux_is_genfs_special_handling(sb);
494
495 /* Never allow relabeling on context mounts */
496 case SECURITY_FS_USE_MNTPOINT:
497 case SECURITY_FS_USE_NONE:
498 default:
499 return 0;
500 }
501}
502
503static int sb_check_xattr_support(struct super_block *sb)
504{
505 struct superblock_security_struct *sbsec = selinux_superblock(sb);
506 struct dentry *root = sb->s_root;
507 struct inode *root_inode = d_backing_inode(root);
508 u32 sid;
509 int rc;
510
511 /*
512 * Make sure that the xattr handler exists and that no
513 * error other than -ENODATA is returned by getxattr on
514 * the root directory. -ENODATA is ok, as this may be
515 * the first boot of the SELinux kernel before we have
516 * assigned xattr values to the filesystem.
517 */
518 if (!(root_inode->i_opflags & IOP_XATTR)) {
519 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
520 sb->s_id, sb->s_type->name);
521 goto fallback;
522 }
523
524 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
525 if (rc < 0 && rc != -ENODATA) {
526 if (rc == -EOPNOTSUPP) {
527 pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
528 sb->s_id, sb->s_type->name);
529 goto fallback;
530 } else {
531 pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
532 sb->s_id, sb->s_type->name, -rc);
533 return rc;
534 }
535 }
536 return 0;
537
538fallback:
539 /* No xattr support - try to fallback to genfs if possible. */
540 rc = security_genfs_sid(sb->s_type->name, "/",
541 SECCLASS_DIR, &sid);
542 if (rc)
543 return -EOPNOTSUPP;
544
545 pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
546 sb->s_id, sb->s_type->name);
547 sbsec->behavior = SECURITY_FS_USE_GENFS;
548 sbsec->sid = sid;
549 return 0;
550}
551
552static int sb_finish_set_opts(struct super_block *sb)
553{
554 struct superblock_security_struct *sbsec = selinux_superblock(sb);
555 struct dentry *root = sb->s_root;
556 struct inode *root_inode = d_backing_inode(root);
557 int rc = 0;
558
559 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
560 rc = sb_check_xattr_support(sb);
561 if (rc)
562 return rc;
563 }
564
565 sbsec->flags |= SE_SBINITIALIZED;
566
567 /*
568 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply
569 * leave the flag untouched because sb_clone_mnt_opts might be handing
570 * us a superblock that needs the flag to be cleared.
571 */
572 if (selinux_is_sblabel_mnt(sb))
573 sbsec->flags |= SBLABEL_MNT;
574 else
575 sbsec->flags &= ~SBLABEL_MNT;
576
577 /* Initialize the root inode. */
578 rc = inode_doinit_with_dentry(root_inode, root);
579
580 /* Initialize any other inodes associated with the superblock, e.g.
581 inodes created prior to initial policy load or inodes created
582 during get_sb by a pseudo filesystem that directly
583 populates itself. */
584 spin_lock(&sbsec->isec_lock);
585 while (!list_empty(&sbsec->isec_head)) {
586 struct inode_security_struct *isec =
587 list_first_entry(&sbsec->isec_head,
588 struct inode_security_struct, list);
589 struct inode *inode = isec->inode;
590 list_del_init(&isec->list);
591 spin_unlock(&sbsec->isec_lock);
592 inode = igrab(inode);
593 if (inode) {
594 if (!IS_PRIVATE(inode))
595 inode_doinit_with_dentry(inode, NULL);
596 iput(inode);
597 }
598 spin_lock(&sbsec->isec_lock);
599 }
600 spin_unlock(&sbsec->isec_lock);
601 return rc;
602}
603
604static int bad_option(struct superblock_security_struct *sbsec, char flag,
605 u32 old_sid, u32 new_sid)
606{
607 char mnt_flags = sbsec->flags & SE_MNTMASK;
608
609 /* check if the old mount command had the same options */
610 if (sbsec->flags & SE_SBINITIALIZED)
611 if (!(sbsec->flags & flag) ||
612 (old_sid != new_sid))
613 return 1;
614
615 /* check if we were passed the same options twice,
616 * aka someone passed context=a,context=b
617 */
618 if (!(sbsec->flags & SE_SBINITIALIZED))
619 if (mnt_flags & flag)
620 return 1;
621 return 0;
622}
623
624/*
625 * Allow filesystems with binary mount data to explicitly set mount point
626 * labeling information.
627 */
628static int selinux_set_mnt_opts(struct super_block *sb,
629 void *mnt_opts,
630 unsigned long kern_flags,
631 unsigned long *set_kern_flags)
632{
633 const struct cred *cred = current_cred();
634 struct superblock_security_struct *sbsec = selinux_superblock(sb);
635 struct dentry *root = sb->s_root;
636 struct selinux_mnt_opts *opts = mnt_opts;
637 struct inode_security_struct *root_isec;
638 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
639 u32 defcontext_sid = 0;
640 int rc = 0;
641
642 /*
643 * Specifying internal flags without providing a place to
644 * place the results is not allowed
645 */
646 if (kern_flags && !set_kern_flags)
647 return -EINVAL;
648
649 mutex_lock(&sbsec->lock);
650
651 if (!selinux_initialized()) {
652 if (!opts) {
653 /* Defer initialization until selinux_complete_init,
654 after the initial policy is loaded and the security
655 server is ready to handle calls. */
656 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
657 sbsec->flags |= SE_SBNATIVE;
658 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
659 }
660 goto out;
661 }
662 rc = -EINVAL;
663 pr_warn("SELinux: Unable to set superblock options "
664 "before the security server is initialized\n");
665 goto out;
666 }
667
668 /*
669 * Binary mount data FS will come through this function twice. Once
670 * from an explicit call and once from the generic calls from the vfs.
671 * Since the generic VFS calls will not contain any security mount data
672 * we need to skip the double mount verification.
673 *
674 * This does open a hole in which we will not notice if the first
675 * mount using this sb set explicit options and a second mount using
676 * this sb does not set any security options. (The first options
677 * will be used for both mounts)
678 */
679 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
680 && !opts)
681 goto out;
682
683 root_isec = backing_inode_security_novalidate(root);
684
685 /*
686 * parse the mount options, check if they are valid sids.
687 * also check if someone is trying to mount the same sb more
688 * than once with different security options.
689 */
690 if (opts) {
691 if (opts->fscontext_sid) {
692 fscontext_sid = opts->fscontext_sid;
693 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
694 fscontext_sid))
695 goto out_double_mount;
696 sbsec->flags |= FSCONTEXT_MNT;
697 }
698 if (opts->context_sid) {
699 context_sid = opts->context_sid;
700 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
701 context_sid))
702 goto out_double_mount;
703 sbsec->flags |= CONTEXT_MNT;
704 }
705 if (opts->rootcontext_sid) {
706 rootcontext_sid = opts->rootcontext_sid;
707 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
708 rootcontext_sid))
709 goto out_double_mount;
710 sbsec->flags |= ROOTCONTEXT_MNT;
711 }
712 if (opts->defcontext_sid) {
713 defcontext_sid = opts->defcontext_sid;
714 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
715 defcontext_sid))
716 goto out_double_mount;
717 sbsec->flags |= DEFCONTEXT_MNT;
718 }
719 }
720
721 if (sbsec->flags & SE_SBINITIALIZED) {
722 /* previously mounted with options, but not on this attempt? */
723 if ((sbsec->flags & SE_MNTMASK) && !opts)
724 goto out_double_mount;
725 rc = 0;
726 goto out;
727 }
728
729 if (strcmp(sb->s_type->name, "proc") == 0)
730 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
731
732 if (!strcmp(sb->s_type->name, "debugfs") ||
733 !strcmp(sb->s_type->name, "tracefs") ||
734 !strcmp(sb->s_type->name, "binder") ||
735 !strcmp(sb->s_type->name, "bpf") ||
736 !strcmp(sb->s_type->name, "pstore") ||
737 !strcmp(sb->s_type->name, "securityfs"))
738 sbsec->flags |= SE_SBGENFS;
739
740 if (!strcmp(sb->s_type->name, "sysfs") ||
741 !strcmp(sb->s_type->name, "cgroup") ||
742 !strcmp(sb->s_type->name, "cgroup2"))
743 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
744
745 if (!sbsec->behavior) {
746 /*
747 * Determine the labeling behavior to use for this
748 * filesystem type.
749 */
750 rc = security_fs_use(sb);
751 if (rc) {
752 pr_warn("%s: security_fs_use(%s) returned %d\n",
753 __func__, sb->s_type->name, rc);
754 goto out;
755 }
756 }
757
758 /*
759 * If this is a user namespace mount and the filesystem type is not
760 * explicitly whitelisted, then no contexts are allowed on the command
761 * line and security labels must be ignored.
762 */
763 if (sb->s_user_ns != &init_user_ns &&
764 strcmp(sb->s_type->name, "tmpfs") &&
765 strcmp(sb->s_type->name, "ramfs") &&
766 strcmp(sb->s_type->name, "devpts") &&
767 strcmp(sb->s_type->name, "overlay")) {
768 if (context_sid || fscontext_sid || rootcontext_sid ||
769 defcontext_sid) {
770 rc = -EACCES;
771 goto out;
772 }
773 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
774 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
775 rc = security_transition_sid(current_sid(),
776 current_sid(),
777 SECCLASS_FILE, NULL,
778 &sbsec->mntpoint_sid);
779 if (rc)
780 goto out;
781 }
782 goto out_set_opts;
783 }
784
785 /* sets the context of the superblock for the fs being mounted. */
786 if (fscontext_sid) {
787 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
788 if (rc)
789 goto out;
790
791 sbsec->sid = fscontext_sid;
792 }
793
794 /*
795 * Switch to using mount point labeling behavior.
796 * sets the label used on all file below the mountpoint, and will set
797 * the superblock context if not already set.
798 */
799 if (sbsec->flags & SE_SBNATIVE) {
800 /*
801 * This means we are initializing a superblock that has been
802 * mounted before the SELinux was initialized and the
803 * filesystem requested native labeling. We had already
804 * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags
805 * in the original mount attempt, so now we just need to set
806 * the SECURITY_FS_USE_NATIVE behavior.
807 */
808 sbsec->behavior = SECURITY_FS_USE_NATIVE;
809 } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
810 sbsec->behavior = SECURITY_FS_USE_NATIVE;
811 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
812 }
813
814 if (context_sid) {
815 if (!fscontext_sid) {
816 rc = may_context_mount_sb_relabel(context_sid, sbsec,
817 cred);
818 if (rc)
819 goto out;
820 sbsec->sid = context_sid;
821 } else {
822 rc = may_context_mount_inode_relabel(context_sid, sbsec,
823 cred);
824 if (rc)
825 goto out;
826 }
827 if (!rootcontext_sid)
828 rootcontext_sid = context_sid;
829
830 sbsec->mntpoint_sid = context_sid;
831 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
832 }
833
834 if (rootcontext_sid) {
835 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
836 cred);
837 if (rc)
838 goto out;
839
840 root_isec->sid = rootcontext_sid;
841 root_isec->initialized = LABEL_INITIALIZED;
842 }
843
844 if (defcontext_sid) {
845 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
846 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
847 rc = -EINVAL;
848 pr_warn("SELinux: defcontext option is "
849 "invalid for this filesystem type\n");
850 goto out;
851 }
852
853 if (defcontext_sid != sbsec->def_sid) {
854 rc = may_context_mount_inode_relabel(defcontext_sid,
855 sbsec, cred);
856 if (rc)
857 goto out;
858 }
859
860 sbsec->def_sid = defcontext_sid;
861 }
862
863out_set_opts:
864 rc = sb_finish_set_opts(sb);
865out:
866 mutex_unlock(&sbsec->lock);
867 return rc;
868out_double_mount:
869 rc = -EINVAL;
870 pr_warn("SELinux: mount invalid. Same superblock, different "
871 "security settings for (dev %s, type %s)\n", sb->s_id,
872 sb->s_type->name);
873 goto out;
874}
875
876static int selinux_cmp_sb_context(const struct super_block *oldsb,
877 const struct super_block *newsb)
878{
879 struct superblock_security_struct *old = selinux_superblock(oldsb);
880 struct superblock_security_struct *new = selinux_superblock(newsb);
881 char oldflags = old->flags & SE_MNTMASK;
882 char newflags = new->flags & SE_MNTMASK;
883
884 if (oldflags != newflags)
885 goto mismatch;
886 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
887 goto mismatch;
888 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
889 goto mismatch;
890 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
891 goto mismatch;
892 if (oldflags & ROOTCONTEXT_MNT) {
893 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
894 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
895 if (oldroot->sid != newroot->sid)
896 goto mismatch;
897 }
898 return 0;
899mismatch:
900 pr_warn("SELinux: mount invalid. Same superblock, "
901 "different security settings for (dev %s, "
902 "type %s)\n", newsb->s_id, newsb->s_type->name);
903 return -EBUSY;
904}
905
906static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
907 struct super_block *newsb,
908 unsigned long kern_flags,
909 unsigned long *set_kern_flags)
910{
911 int rc = 0;
912 const struct superblock_security_struct *oldsbsec =
913 selinux_superblock(oldsb);
914 struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
915
916 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
917 int set_context = (oldsbsec->flags & CONTEXT_MNT);
918 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
919
920 /*
921 * Specifying internal flags without providing a place to
922 * place the results is not allowed.
923 */
924 if (kern_flags && !set_kern_flags)
925 return -EINVAL;
926
927 mutex_lock(&newsbsec->lock);
928
929 /*
930 * if the parent was able to be mounted it clearly had no special lsm
931 * mount options. thus we can safely deal with this superblock later
932 */
933 if (!selinux_initialized()) {
934 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
935 newsbsec->flags |= SE_SBNATIVE;
936 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
937 }
938 goto out;
939 }
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 mutex_unlock(&newsbsec->lock);
947 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
948 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
949 return selinux_cmp_sb_context(oldsb, newsb);
950 }
951
952 newsbsec->flags = oldsbsec->flags;
953
954 newsbsec->sid = oldsbsec->sid;
955 newsbsec->def_sid = oldsbsec->def_sid;
956 newsbsec->behavior = oldsbsec->behavior;
957
958 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
959 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
960 rc = security_fs_use(newsb);
961 if (rc)
962 goto out;
963 }
964
965 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
966 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
967 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
968 }
969
970 if (set_context) {
971 u32 sid = oldsbsec->mntpoint_sid;
972
973 if (!set_fscontext)
974 newsbsec->sid = sid;
975 if (!set_rootcontext) {
976 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
977 newisec->sid = sid;
978 }
979 newsbsec->mntpoint_sid = sid;
980 }
981 if (set_rootcontext) {
982 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
983 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
984
985 newisec->sid = oldisec->sid;
986 }
987
988 sb_finish_set_opts(newsb);
989out:
990 mutex_unlock(&newsbsec->lock);
991 return rc;
992}
993
994/*
995 * NOTE: the caller is responsible for freeing the memory even if on error.
996 */
997static int selinux_add_opt(int token, const char *s, void **mnt_opts)
998{
999 struct selinux_mnt_opts *opts = *mnt_opts;
1000 u32 *dst_sid;
1001 int rc;
1002
1003 if (token == Opt_seclabel)
1004 /* eaten and completely ignored */
1005 return 0;
1006 if (!s)
1007 return -EINVAL;
1008
1009 if (!selinux_initialized()) {
1010 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n");
1011 return -EINVAL;
1012 }
1013
1014 if (!opts) {
1015 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1016 if (!opts)
1017 return -ENOMEM;
1018 *mnt_opts = opts;
1019 }
1020
1021 switch (token) {
1022 case Opt_context:
1023 if (opts->context_sid || opts->defcontext_sid)
1024 goto err;
1025 dst_sid = &opts->context_sid;
1026 break;
1027 case Opt_fscontext:
1028 if (opts->fscontext_sid)
1029 goto err;
1030 dst_sid = &opts->fscontext_sid;
1031 break;
1032 case Opt_rootcontext:
1033 if (opts->rootcontext_sid)
1034 goto err;
1035 dst_sid = &opts->rootcontext_sid;
1036 break;
1037 case Opt_defcontext:
1038 if (opts->context_sid || opts->defcontext_sid)
1039 goto err;
1040 dst_sid = &opts->defcontext_sid;
1041 break;
1042 default:
1043 WARN_ON(1);
1044 return -EINVAL;
1045 }
1046 rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL);
1047 if (rc)
1048 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n",
1049 s, rc);
1050 return rc;
1051
1052err:
1053 pr_warn(SEL_MOUNT_FAIL_MSG);
1054 return -EINVAL;
1055}
1056
1057static int show_sid(struct seq_file *m, u32 sid)
1058{
1059 char *context = NULL;
1060 u32 len;
1061 int rc;
1062
1063 rc = security_sid_to_context(sid, &context, &len);
1064 if (!rc) {
1065 bool has_comma = strchr(context, ',');
1066
1067 seq_putc(m, '=');
1068 if (has_comma)
1069 seq_putc(m, '\"');
1070 seq_escape(m, context, "\"\n\\");
1071 if (has_comma)
1072 seq_putc(m, '\"');
1073 }
1074 kfree(context);
1075 return rc;
1076}
1077
1078static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1079{
1080 struct superblock_security_struct *sbsec = selinux_superblock(sb);
1081 int rc;
1082
1083 if (!(sbsec->flags & SE_SBINITIALIZED))
1084 return 0;
1085
1086 if (!selinux_initialized())
1087 return 0;
1088
1089 if (sbsec->flags & FSCONTEXT_MNT) {
1090 seq_putc(m, ',');
1091 seq_puts(m, FSCONTEXT_STR);
1092 rc = show_sid(m, sbsec->sid);
1093 if (rc)
1094 return rc;
1095 }
1096 if (sbsec->flags & CONTEXT_MNT) {
1097 seq_putc(m, ',');
1098 seq_puts(m, CONTEXT_STR);
1099 rc = show_sid(m, sbsec->mntpoint_sid);
1100 if (rc)
1101 return rc;
1102 }
1103 if (sbsec->flags & DEFCONTEXT_MNT) {
1104 seq_putc(m, ',');
1105 seq_puts(m, DEFCONTEXT_STR);
1106 rc = show_sid(m, sbsec->def_sid);
1107 if (rc)
1108 return rc;
1109 }
1110 if (sbsec->flags & ROOTCONTEXT_MNT) {
1111 struct dentry *root = sb->s_root;
1112 struct inode_security_struct *isec = backing_inode_security(root);
1113 seq_putc(m, ',');
1114 seq_puts(m, ROOTCONTEXT_STR);
1115 rc = show_sid(m, isec->sid);
1116 if (rc)
1117 return rc;
1118 }
1119 if (sbsec->flags & SBLABEL_MNT) {
1120 seq_putc(m, ',');
1121 seq_puts(m, SECLABEL_STR);
1122 }
1123 return 0;
1124}
1125
1126static inline u16 inode_mode_to_security_class(umode_t mode)
1127{
1128 switch (mode & S_IFMT) {
1129 case S_IFSOCK:
1130 return SECCLASS_SOCK_FILE;
1131 case S_IFLNK:
1132 return SECCLASS_LNK_FILE;
1133 case S_IFREG:
1134 return SECCLASS_FILE;
1135 case S_IFBLK:
1136 return SECCLASS_BLK_FILE;
1137 case S_IFDIR:
1138 return SECCLASS_DIR;
1139 case S_IFCHR:
1140 return SECCLASS_CHR_FILE;
1141 case S_IFIFO:
1142 return SECCLASS_FIFO_FILE;
1143
1144 }
1145
1146 return SECCLASS_FILE;
1147}
1148
1149static inline int default_protocol_stream(int protocol)
1150{
1151 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1152 protocol == IPPROTO_MPTCP);
1153}
1154
1155static inline int default_protocol_dgram(int protocol)
1156{
1157 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1158}
1159
1160static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1161{
1162 bool extsockclass = selinux_policycap_extsockclass();
1163
1164 switch (family) {
1165 case PF_UNIX:
1166 switch (type) {
1167 case SOCK_STREAM:
1168 case SOCK_SEQPACKET:
1169 return SECCLASS_UNIX_STREAM_SOCKET;
1170 case SOCK_DGRAM:
1171 case SOCK_RAW:
1172 return SECCLASS_UNIX_DGRAM_SOCKET;
1173 }
1174 break;
1175 case PF_INET:
1176 case PF_INET6:
1177 switch (type) {
1178 case SOCK_STREAM:
1179 case SOCK_SEQPACKET:
1180 if (default_protocol_stream(protocol))
1181 return SECCLASS_TCP_SOCKET;
1182 else if (extsockclass && protocol == IPPROTO_SCTP)
1183 return SECCLASS_SCTP_SOCKET;
1184 else
1185 return SECCLASS_RAWIP_SOCKET;
1186 case SOCK_DGRAM:
1187 if (default_protocol_dgram(protocol))
1188 return SECCLASS_UDP_SOCKET;
1189 else if (extsockclass && (protocol == IPPROTO_ICMP ||
1190 protocol == IPPROTO_ICMPV6))
1191 return SECCLASS_ICMP_SOCKET;
1192 else
1193 return SECCLASS_RAWIP_SOCKET;
1194 case SOCK_DCCP:
1195 return SECCLASS_DCCP_SOCKET;
1196 default:
1197 return SECCLASS_RAWIP_SOCKET;
1198 }
1199 break;
1200 case PF_NETLINK:
1201 switch (protocol) {
1202 case NETLINK_ROUTE:
1203 return SECCLASS_NETLINK_ROUTE_SOCKET;
1204 case NETLINK_SOCK_DIAG:
1205 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1206 case NETLINK_NFLOG:
1207 return SECCLASS_NETLINK_NFLOG_SOCKET;
1208 case NETLINK_XFRM:
1209 return SECCLASS_NETLINK_XFRM_SOCKET;
1210 case NETLINK_SELINUX:
1211 return SECCLASS_NETLINK_SELINUX_SOCKET;
1212 case NETLINK_ISCSI:
1213 return SECCLASS_NETLINK_ISCSI_SOCKET;
1214 case NETLINK_AUDIT:
1215 return SECCLASS_NETLINK_AUDIT_SOCKET;
1216 case NETLINK_FIB_LOOKUP:
1217 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1218 case NETLINK_CONNECTOR:
1219 return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1220 case NETLINK_NETFILTER:
1221 return SECCLASS_NETLINK_NETFILTER_SOCKET;
1222 case NETLINK_DNRTMSG:
1223 return SECCLASS_NETLINK_DNRT_SOCKET;
1224 case NETLINK_KOBJECT_UEVENT:
1225 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1226 case NETLINK_GENERIC:
1227 return SECCLASS_NETLINK_GENERIC_SOCKET;
1228 case NETLINK_SCSITRANSPORT:
1229 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1230 case NETLINK_RDMA:
1231 return SECCLASS_NETLINK_RDMA_SOCKET;
1232 case NETLINK_CRYPTO:
1233 return SECCLASS_NETLINK_CRYPTO_SOCKET;
1234 default:
1235 return SECCLASS_NETLINK_SOCKET;
1236 }
1237 case PF_PACKET:
1238 return SECCLASS_PACKET_SOCKET;
1239 case PF_KEY:
1240 return SECCLASS_KEY_SOCKET;
1241 case PF_APPLETALK:
1242 return SECCLASS_APPLETALK_SOCKET;
1243 }
1244
1245 if (extsockclass) {
1246 switch (family) {
1247 case PF_AX25:
1248 return SECCLASS_AX25_SOCKET;
1249 case PF_IPX:
1250 return SECCLASS_IPX_SOCKET;
1251 case PF_NETROM:
1252 return SECCLASS_NETROM_SOCKET;
1253 case PF_ATMPVC:
1254 return SECCLASS_ATMPVC_SOCKET;
1255 case PF_X25:
1256 return SECCLASS_X25_SOCKET;
1257 case PF_ROSE:
1258 return SECCLASS_ROSE_SOCKET;
1259 case PF_DECnet:
1260 return SECCLASS_DECNET_SOCKET;
1261 case PF_ATMSVC:
1262 return SECCLASS_ATMSVC_SOCKET;
1263 case PF_RDS:
1264 return SECCLASS_RDS_SOCKET;
1265 case PF_IRDA:
1266 return SECCLASS_IRDA_SOCKET;
1267 case PF_PPPOX:
1268 return SECCLASS_PPPOX_SOCKET;
1269 case PF_LLC:
1270 return SECCLASS_LLC_SOCKET;
1271 case PF_CAN:
1272 return SECCLASS_CAN_SOCKET;
1273 case PF_TIPC:
1274 return SECCLASS_TIPC_SOCKET;
1275 case PF_BLUETOOTH:
1276 return SECCLASS_BLUETOOTH_SOCKET;
1277 case PF_IUCV:
1278 return SECCLASS_IUCV_SOCKET;
1279 case PF_RXRPC:
1280 return SECCLASS_RXRPC_SOCKET;
1281 case PF_ISDN:
1282 return SECCLASS_ISDN_SOCKET;
1283 case PF_PHONET:
1284 return SECCLASS_PHONET_SOCKET;
1285 case PF_IEEE802154:
1286 return SECCLASS_IEEE802154_SOCKET;
1287 case PF_CAIF:
1288 return SECCLASS_CAIF_SOCKET;
1289 case PF_ALG:
1290 return SECCLASS_ALG_SOCKET;
1291 case PF_NFC:
1292 return SECCLASS_NFC_SOCKET;
1293 case PF_VSOCK:
1294 return SECCLASS_VSOCK_SOCKET;
1295 case PF_KCM:
1296 return SECCLASS_KCM_SOCKET;
1297 case PF_QIPCRTR:
1298 return SECCLASS_QIPCRTR_SOCKET;
1299 case PF_SMC:
1300 return SECCLASS_SMC_SOCKET;
1301 case PF_XDP:
1302 return SECCLASS_XDP_SOCKET;
1303 case PF_MCTP:
1304 return SECCLASS_MCTP_SOCKET;
1305#if PF_MAX > 46
1306#error New address family defined, please update this function.
1307#endif
1308 }
1309 }
1310
1311 return SECCLASS_SOCKET;
1312}
1313
1314static int selinux_genfs_get_sid(struct dentry *dentry,
1315 u16 tclass,
1316 u16 flags,
1317 u32 *sid)
1318{
1319 int rc;
1320 struct super_block *sb = dentry->d_sb;
1321 char *buffer, *path;
1322
1323 buffer = (char *)__get_free_page(GFP_KERNEL);
1324 if (!buffer)
1325 return -ENOMEM;
1326
1327 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1328 if (IS_ERR(path))
1329 rc = PTR_ERR(path);
1330 else {
1331 if (flags & SE_SBPROC) {
1332 /* each process gets a /proc/PID/ entry. Strip off the
1333 * PID part to get a valid selinux labeling.
1334 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1335 while (path[1] >= '0' && path[1] <= '9') {
1336 path[1] = '/';
1337 path++;
1338 }
1339 }
1340 rc = security_genfs_sid(sb->s_type->name,
1341 path, tclass, sid);
1342 if (rc == -ENOENT) {
1343 /* No match in policy, mark as unlabeled. */
1344 *sid = SECINITSID_UNLABELED;
1345 rc = 0;
1346 }
1347 }
1348 free_page((unsigned long)buffer);
1349 return rc;
1350}
1351
1352static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1353 u32 def_sid, u32 *sid)
1354{
1355#define INITCONTEXTLEN 255
1356 char *context;
1357 unsigned int len;
1358 int rc;
1359
1360 len = INITCONTEXTLEN;
1361 context = kmalloc(len + 1, GFP_NOFS);
1362 if (!context)
1363 return -ENOMEM;
1364
1365 context[len] = '\0';
1366 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1367 if (rc == -ERANGE) {
1368 kfree(context);
1369
1370 /* Need a larger buffer. Query for the right size. */
1371 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1372 if (rc < 0)
1373 return rc;
1374
1375 len = rc;
1376 context = kmalloc(len + 1, GFP_NOFS);
1377 if (!context)
1378 return -ENOMEM;
1379
1380 context[len] = '\0';
1381 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1382 context, len);
1383 }
1384 if (rc < 0) {
1385 kfree(context);
1386 if (rc != -ENODATA) {
1387 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n",
1388 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1389 return rc;
1390 }
1391 *sid = def_sid;
1392 return 0;
1393 }
1394
1395 rc = security_context_to_sid_default(context, rc, sid,
1396 def_sid, GFP_NOFS);
1397 if (rc) {
1398 char *dev = inode->i_sb->s_id;
1399 unsigned long ino = inode->i_ino;
1400
1401 if (rc == -EINVAL) {
1402 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",
1403 ino, dev, context);
1404 } else {
1405 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1406 __func__, context, -rc, dev, ino);
1407 }
1408 }
1409 kfree(context);
1410 return 0;
1411}
1412
1413/* The inode's security attributes must be initialized before first use. */
1414static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1415{
1416 struct superblock_security_struct *sbsec = NULL;
1417 struct inode_security_struct *isec = selinux_inode(inode);
1418 u32 task_sid, sid = 0;
1419 u16 sclass;
1420 struct dentry *dentry;
1421 int rc = 0;
1422
1423 if (isec->initialized == LABEL_INITIALIZED)
1424 return 0;
1425
1426 spin_lock(&isec->lock);
1427 if (isec->initialized == LABEL_INITIALIZED)
1428 goto out_unlock;
1429
1430 if (isec->sclass == SECCLASS_FILE)
1431 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1432
1433 sbsec = selinux_superblock(inode->i_sb);
1434 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1435 /* Defer initialization until selinux_complete_init,
1436 after the initial policy is loaded and the security
1437 server is ready to handle calls. */
1438 spin_lock(&sbsec->isec_lock);
1439 if (list_empty(&isec->list))
1440 list_add(&isec->list, &sbsec->isec_head);
1441 spin_unlock(&sbsec->isec_lock);
1442 goto out_unlock;
1443 }
1444
1445 sclass = isec->sclass;
1446 task_sid = isec->task_sid;
1447 sid = isec->sid;
1448 isec->initialized = LABEL_PENDING;
1449 spin_unlock(&isec->lock);
1450
1451 switch (sbsec->behavior) {
1452 /*
1453 * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels
1454 * via xattr when called from delayed_superblock_init().
1455 */
1456 case SECURITY_FS_USE_NATIVE:
1457 case SECURITY_FS_USE_XATTR:
1458 if (!(inode->i_opflags & IOP_XATTR)) {
1459 sid = sbsec->def_sid;
1460 break;
1461 }
1462 /* Need a dentry, since the xattr API requires one.
1463 Life would be simpler if we could just pass the inode. */
1464 if (opt_dentry) {
1465 /* Called from d_instantiate or d_splice_alias. */
1466 dentry = dget(opt_dentry);
1467 } else {
1468 /*
1469 * Called from selinux_complete_init, try to find a dentry.
1470 * Some filesystems really want a connected one, so try
1471 * that first. We could split SECURITY_FS_USE_XATTR in
1472 * two, depending upon that...
1473 */
1474 dentry = d_find_alias(inode);
1475 if (!dentry)
1476 dentry = d_find_any_alias(inode);
1477 }
1478 if (!dentry) {
1479 /*
1480 * this is can be hit on boot when a file is accessed
1481 * before the policy is loaded. When we load policy we
1482 * may find inodes that have no dentry on the
1483 * sbsec->isec_head list. No reason to complain as these
1484 * will get fixed up the next time we go through
1485 * inode_doinit with a dentry, before these inodes could
1486 * be used again by userspace.
1487 */
1488 goto out_invalid;
1489 }
1490
1491 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1492 &sid);
1493 dput(dentry);
1494 if (rc)
1495 goto out;
1496 break;
1497 case SECURITY_FS_USE_TASK:
1498 sid = task_sid;
1499 break;
1500 case SECURITY_FS_USE_TRANS:
1501 /* Default to the fs SID. */
1502 sid = sbsec->sid;
1503
1504 /* Try to obtain a transition SID. */
1505 rc = security_transition_sid(task_sid, sid,
1506 sclass, NULL, &sid);
1507 if (rc)
1508 goto out;
1509 break;
1510 case SECURITY_FS_USE_MNTPOINT:
1511 sid = sbsec->mntpoint_sid;
1512 break;
1513 default:
1514 /* Default to the fs superblock SID. */
1515 sid = sbsec->sid;
1516
1517 if ((sbsec->flags & SE_SBGENFS) &&
1518 (!S_ISLNK(inode->i_mode) ||
1519 selinux_policycap_genfs_seclabel_symlinks())) {
1520 /* We must have a dentry to determine the label on
1521 * procfs inodes */
1522 if (opt_dentry) {
1523 /* Called from d_instantiate or
1524 * d_splice_alias. */
1525 dentry = dget(opt_dentry);
1526 } else {
1527 /* Called from selinux_complete_init, try to
1528 * find a dentry. Some filesystems really want
1529 * a connected one, so try that first.
1530 */
1531 dentry = d_find_alias(inode);
1532 if (!dentry)
1533 dentry = d_find_any_alias(inode);
1534 }
1535 /*
1536 * This can be hit on boot when a file is accessed
1537 * before the policy is loaded. When we load policy we
1538 * may find inodes that have no dentry on the
1539 * sbsec->isec_head list. No reason to complain as
1540 * these will get fixed up the next time we go through
1541 * inode_doinit() with a dentry, before these inodes
1542 * could be used again by userspace.
1543 */
1544 if (!dentry)
1545 goto out_invalid;
1546 rc = selinux_genfs_get_sid(dentry, sclass,
1547 sbsec->flags, &sid);
1548 if (rc) {
1549 dput(dentry);
1550 goto out;
1551 }
1552
1553 if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1554 (inode->i_opflags & IOP_XATTR)) {
1555 rc = inode_doinit_use_xattr(inode, dentry,
1556 sid, &sid);
1557 if (rc) {
1558 dput(dentry);
1559 goto out;
1560 }
1561 }
1562 dput(dentry);
1563 }
1564 break;
1565 }
1566
1567out:
1568 spin_lock(&isec->lock);
1569 if (isec->initialized == LABEL_PENDING) {
1570 if (rc) {
1571 isec->initialized = LABEL_INVALID;
1572 goto out_unlock;
1573 }
1574 isec->initialized = LABEL_INITIALIZED;
1575 isec->sid = sid;
1576 }
1577
1578out_unlock:
1579 spin_unlock(&isec->lock);
1580 return rc;
1581
1582out_invalid:
1583 spin_lock(&isec->lock);
1584 if (isec->initialized == LABEL_PENDING) {
1585 isec->initialized = LABEL_INVALID;
1586 isec->sid = sid;
1587 }
1588 spin_unlock(&isec->lock);
1589 return 0;
1590}
1591
1592/* Convert a Linux signal to an access vector. */
1593static inline u32 signal_to_av(int sig)
1594{
1595 u32 perm = 0;
1596
1597 switch (sig) {
1598 case SIGCHLD:
1599 /* Commonly granted from child to parent. */
1600 perm = PROCESS__SIGCHLD;
1601 break;
1602 case SIGKILL:
1603 /* Cannot be caught or ignored */
1604 perm = PROCESS__SIGKILL;
1605 break;
1606 case SIGSTOP:
1607 /* Cannot be caught or ignored */
1608 perm = PROCESS__SIGSTOP;
1609 break;
1610 default:
1611 /* All other signals. */
1612 perm = PROCESS__SIGNAL;
1613 break;
1614 }
1615
1616 return perm;
1617}
1618
1619#if CAP_LAST_CAP > 63
1620#error Fix SELinux to handle capabilities > 63.
1621#endif
1622
1623/* Check whether a task is allowed to use a capability. */
1624static int cred_has_capability(const struct cred *cred,
1625 int cap, unsigned int opts, bool initns)
1626{
1627 struct common_audit_data ad;
1628 struct av_decision avd;
1629 u16 sclass;
1630 u32 sid = cred_sid(cred);
1631 u32 av = CAP_TO_MASK(cap);
1632 int rc;
1633
1634 ad.type = LSM_AUDIT_DATA_CAP;
1635 ad.u.cap = cap;
1636
1637 switch (CAP_TO_INDEX(cap)) {
1638 case 0:
1639 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1640 break;
1641 case 1:
1642 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1643 break;
1644 default:
1645 pr_err("SELinux: out of range capability %d\n", cap);
1646 BUG();
1647 return -EINVAL;
1648 }
1649
1650 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1651 if (!(opts & CAP_OPT_NOAUDIT)) {
1652 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1653 if (rc2)
1654 return rc2;
1655 }
1656 return rc;
1657}
1658
1659/* Check whether a task has a particular permission to an inode.
1660 The 'adp' parameter is optional and allows other audit
1661 data to be passed (e.g. the dentry). */
1662static int inode_has_perm(const struct cred *cred,
1663 struct inode *inode,
1664 u32 perms,
1665 struct common_audit_data *adp)
1666{
1667 struct inode_security_struct *isec;
1668 u32 sid;
1669
1670 if (unlikely(IS_PRIVATE(inode)))
1671 return 0;
1672
1673 sid = cred_sid(cred);
1674 isec = selinux_inode(inode);
1675
1676 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1677}
1678
1679/* Same as inode_has_perm, but pass explicit audit data containing
1680 the dentry to help the auditing code to more easily generate the
1681 pathname if needed. */
1682static inline int dentry_has_perm(const struct cred *cred,
1683 struct dentry *dentry,
1684 u32 av)
1685{
1686 struct inode *inode = d_backing_inode(dentry);
1687 struct common_audit_data ad;
1688
1689 ad.type = LSM_AUDIT_DATA_DENTRY;
1690 ad.u.dentry = dentry;
1691 __inode_security_revalidate(inode, dentry, true);
1692 return inode_has_perm(cred, inode, av, &ad);
1693}
1694
1695/* Same as inode_has_perm, but pass explicit audit data containing
1696 the path to help the auditing code to more easily generate the
1697 pathname if needed. */
1698static inline int path_has_perm(const struct cred *cred,
1699 const struct path *path,
1700 u32 av)
1701{
1702 struct inode *inode = d_backing_inode(path->dentry);
1703 struct common_audit_data ad;
1704
1705 ad.type = LSM_AUDIT_DATA_PATH;
1706 ad.u.path = *path;
1707 __inode_security_revalidate(inode, path->dentry, true);
1708 return inode_has_perm(cred, inode, av, &ad);
1709}
1710
1711/* Same as path_has_perm, but uses the inode from the file struct. */
1712static inline int file_path_has_perm(const struct cred *cred,
1713 struct file *file,
1714 u32 av)
1715{
1716 struct common_audit_data ad;
1717
1718 ad.type = LSM_AUDIT_DATA_FILE;
1719 ad.u.file = file;
1720 return inode_has_perm(cred, file_inode(file), av, &ad);
1721}
1722
1723#ifdef CONFIG_BPF_SYSCALL
1724static int bpf_fd_pass(const struct file *file, u32 sid);
1725#endif
1726
1727/* Check whether a task can use an open file descriptor to
1728 access an inode in a given way. Check access to the
1729 descriptor itself, and then use dentry_has_perm to
1730 check a particular permission to the file.
1731 Access to the descriptor is implicitly granted if it
1732 has the same SID as the process. If av is zero, then
1733 access to the file is not checked, e.g. for cases
1734 where only the descriptor is affected like seek. */
1735static int file_has_perm(const struct cred *cred,
1736 struct file *file,
1737 u32 av)
1738{
1739 struct file_security_struct *fsec = selinux_file(file);
1740 struct inode *inode = file_inode(file);
1741 struct common_audit_data ad;
1742 u32 sid = cred_sid(cred);
1743 int rc;
1744
1745 ad.type = LSM_AUDIT_DATA_FILE;
1746 ad.u.file = file;
1747
1748 if (sid != fsec->sid) {
1749 rc = avc_has_perm(sid, fsec->sid,
1750 SECCLASS_FD,
1751 FD__USE,
1752 &ad);
1753 if (rc)
1754 goto out;
1755 }
1756
1757#ifdef CONFIG_BPF_SYSCALL
1758 rc = bpf_fd_pass(file, cred_sid(cred));
1759 if (rc)
1760 return rc;
1761#endif
1762
1763 /* av is zero if only checking access to the descriptor. */
1764 rc = 0;
1765 if (av)
1766 rc = inode_has_perm(cred, inode, av, &ad);
1767
1768out:
1769 return rc;
1770}
1771
1772/*
1773 * Determine the label for an inode that might be unioned.
1774 */
1775static int
1776selinux_determine_inode_label(const struct task_security_struct *tsec,
1777 struct inode *dir,
1778 const struct qstr *name, u16 tclass,
1779 u32 *_new_isid)
1780{
1781 const struct superblock_security_struct *sbsec =
1782 selinux_superblock(dir->i_sb);
1783
1784 if ((sbsec->flags & SE_SBINITIALIZED) &&
1785 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1786 *_new_isid = sbsec->mntpoint_sid;
1787 } else if ((sbsec->flags & SBLABEL_MNT) &&
1788 tsec->create_sid) {
1789 *_new_isid = tsec->create_sid;
1790 } else {
1791 const struct inode_security_struct *dsec = inode_security(dir);
1792 return security_transition_sid(tsec->sid,
1793 dsec->sid, tclass,
1794 name, _new_isid);
1795 }
1796
1797 return 0;
1798}
1799
1800/* Check whether a task can create a file. */
1801static int may_create(struct inode *dir,
1802 struct dentry *dentry,
1803 u16 tclass)
1804{
1805 const struct task_security_struct *tsec = selinux_cred(current_cred());
1806 struct inode_security_struct *dsec;
1807 struct superblock_security_struct *sbsec;
1808 u32 sid, newsid;
1809 struct common_audit_data ad;
1810 int rc;
1811
1812 dsec = inode_security(dir);
1813 sbsec = selinux_superblock(dir->i_sb);
1814
1815 sid = tsec->sid;
1816
1817 ad.type = LSM_AUDIT_DATA_DENTRY;
1818 ad.u.dentry = dentry;
1819
1820 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1821 DIR__ADD_NAME | DIR__SEARCH,
1822 &ad);
1823 if (rc)
1824 return rc;
1825
1826 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1827 &newsid);
1828 if (rc)
1829 return rc;
1830
1831 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1832 if (rc)
1833 return rc;
1834
1835 return avc_has_perm(newsid, sbsec->sid,
1836 SECCLASS_FILESYSTEM,
1837 FILESYSTEM__ASSOCIATE, &ad);
1838}
1839
1840#define MAY_LINK 0
1841#define MAY_UNLINK 1
1842#define MAY_RMDIR 2
1843
1844/* Check whether a task can link, unlink, or rmdir a file/directory. */
1845static int may_link(struct inode *dir,
1846 struct dentry *dentry,
1847 int kind)
1848
1849{
1850 struct inode_security_struct *dsec, *isec;
1851 struct common_audit_data ad;
1852 u32 sid = current_sid();
1853 u32 av;
1854 int rc;
1855
1856 dsec = inode_security(dir);
1857 isec = backing_inode_security(dentry);
1858
1859 ad.type = LSM_AUDIT_DATA_DENTRY;
1860 ad.u.dentry = dentry;
1861
1862 av = DIR__SEARCH;
1863 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1864 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1865 if (rc)
1866 return rc;
1867
1868 switch (kind) {
1869 case MAY_LINK:
1870 av = FILE__LINK;
1871 break;
1872 case MAY_UNLINK:
1873 av = FILE__UNLINK;
1874 break;
1875 case MAY_RMDIR:
1876 av = DIR__RMDIR;
1877 break;
1878 default:
1879 pr_warn("SELinux: %s: unrecognized kind %d\n",
1880 __func__, kind);
1881 return 0;
1882 }
1883
1884 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1885 return rc;
1886}
1887
1888static inline int may_rename(struct inode *old_dir,
1889 struct dentry *old_dentry,
1890 struct inode *new_dir,
1891 struct dentry *new_dentry)
1892{
1893 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1894 struct common_audit_data ad;
1895 u32 sid = current_sid();
1896 u32 av;
1897 int old_is_dir, new_is_dir;
1898 int rc;
1899
1900 old_dsec = inode_security(old_dir);
1901 old_isec = backing_inode_security(old_dentry);
1902 old_is_dir = d_is_dir(old_dentry);
1903 new_dsec = inode_security(new_dir);
1904
1905 ad.type = LSM_AUDIT_DATA_DENTRY;
1906
1907 ad.u.dentry = old_dentry;
1908 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1909 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1910 if (rc)
1911 return rc;
1912 rc = avc_has_perm(sid, old_isec->sid,
1913 old_isec->sclass, FILE__RENAME, &ad);
1914 if (rc)
1915 return rc;
1916 if (old_is_dir && new_dir != old_dir) {
1917 rc = avc_has_perm(sid, old_isec->sid,
1918 old_isec->sclass, DIR__REPARENT, &ad);
1919 if (rc)
1920 return rc;
1921 }
1922
1923 ad.u.dentry = new_dentry;
1924 av = DIR__ADD_NAME | DIR__SEARCH;
1925 if (d_is_positive(new_dentry))
1926 av |= DIR__REMOVE_NAME;
1927 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1928 if (rc)
1929 return rc;
1930 if (d_is_positive(new_dentry)) {
1931 new_isec = backing_inode_security(new_dentry);
1932 new_is_dir = d_is_dir(new_dentry);
1933 rc = avc_has_perm(sid, new_isec->sid,
1934 new_isec->sclass,
1935 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1936 if (rc)
1937 return rc;
1938 }
1939
1940 return 0;
1941}
1942
1943/* Check whether a task can perform a filesystem operation. */
1944static int superblock_has_perm(const struct cred *cred,
1945 const struct super_block *sb,
1946 u32 perms,
1947 struct common_audit_data *ad)
1948{
1949 struct superblock_security_struct *sbsec;
1950 u32 sid = cred_sid(cred);
1951
1952 sbsec = selinux_superblock(sb);
1953 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1954}
1955
1956/* Convert a Linux mode and permission mask to an access vector. */
1957static inline u32 file_mask_to_av(int mode, int mask)
1958{
1959 u32 av = 0;
1960
1961 if (!S_ISDIR(mode)) {
1962 if (mask & MAY_EXEC)
1963 av |= FILE__EXECUTE;
1964 if (mask & MAY_READ)
1965 av |= FILE__READ;
1966
1967 if (mask & MAY_APPEND)
1968 av |= FILE__APPEND;
1969 else if (mask & MAY_WRITE)
1970 av |= FILE__WRITE;
1971
1972 } else {
1973 if (mask & MAY_EXEC)
1974 av |= DIR__SEARCH;
1975 if (mask & MAY_WRITE)
1976 av |= DIR__WRITE;
1977 if (mask & MAY_READ)
1978 av |= DIR__READ;
1979 }
1980
1981 return av;
1982}
1983
1984/* Convert a Linux file to an access vector. */
1985static inline u32 file_to_av(const struct file *file)
1986{
1987 u32 av = 0;
1988
1989 if (file->f_mode & FMODE_READ)
1990 av |= FILE__READ;
1991 if (file->f_mode & FMODE_WRITE) {
1992 if (file->f_flags & O_APPEND)
1993 av |= FILE__APPEND;
1994 else
1995 av |= FILE__WRITE;
1996 }
1997 if (!av) {
1998 /*
1999 * Special file opened with flags 3 for ioctl-only use.
2000 */
2001 av = FILE__IOCTL;
2002 }
2003
2004 return av;
2005}
2006
2007/*
2008 * Convert a file to an access vector and include the correct
2009 * open permission.
2010 */
2011static inline u32 open_file_to_av(struct file *file)
2012{
2013 u32 av = file_to_av(file);
2014 struct inode *inode = file_inode(file);
2015
2016 if (selinux_policycap_openperm() &&
2017 inode->i_sb->s_magic != SOCKFS_MAGIC)
2018 av |= FILE__OPEN;
2019
2020 return av;
2021}
2022
2023/* Hook functions begin here. */
2024
2025static int selinux_binder_set_context_mgr(const struct cred *mgr)
2026{
2027 return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER,
2028 BINDER__SET_CONTEXT_MGR, NULL);
2029}
2030
2031static int selinux_binder_transaction(const struct cred *from,
2032 const struct cred *to)
2033{
2034 u32 mysid = current_sid();
2035 u32 fromsid = cred_sid(from);
2036 u32 tosid = cred_sid(to);
2037 int rc;
2038
2039 if (mysid != fromsid) {
2040 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2041 BINDER__IMPERSONATE, NULL);
2042 if (rc)
2043 return rc;
2044 }
2045
2046 return avc_has_perm(fromsid, tosid,
2047 SECCLASS_BINDER, BINDER__CALL, NULL);
2048}
2049
2050static int selinux_binder_transfer_binder(const struct cred *from,
2051 const struct cred *to)
2052{
2053 return avc_has_perm(cred_sid(from), cred_sid(to),
2054 SECCLASS_BINDER, BINDER__TRANSFER,
2055 NULL);
2056}
2057
2058static int selinux_binder_transfer_file(const struct cred *from,
2059 const struct cred *to,
2060 const struct file *file)
2061{
2062 u32 sid = cred_sid(to);
2063 struct file_security_struct *fsec = selinux_file(file);
2064 struct dentry *dentry = file->f_path.dentry;
2065 struct inode_security_struct *isec;
2066 struct common_audit_data ad;
2067 int rc;
2068
2069 ad.type = LSM_AUDIT_DATA_PATH;
2070 ad.u.path = file->f_path;
2071
2072 if (sid != fsec->sid) {
2073 rc = avc_has_perm(sid, fsec->sid,
2074 SECCLASS_FD,
2075 FD__USE,
2076 &ad);
2077 if (rc)
2078 return rc;
2079 }
2080
2081#ifdef CONFIG_BPF_SYSCALL
2082 rc = bpf_fd_pass(file, sid);
2083 if (rc)
2084 return rc;
2085#endif
2086
2087 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2088 return 0;
2089
2090 isec = backing_inode_security(dentry);
2091 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2092 &ad);
2093}
2094
2095static int selinux_ptrace_access_check(struct task_struct *child,
2096 unsigned int mode)
2097{
2098 u32 sid = current_sid();
2099 u32 csid = task_sid_obj(child);
2100
2101 if (mode & PTRACE_MODE_READ)
2102 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ,
2103 NULL);
2104
2105 return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE,
2106 NULL);
2107}
2108
2109static int selinux_ptrace_traceme(struct task_struct *parent)
2110{
2111 return avc_has_perm(task_sid_obj(parent), task_sid_obj(current),
2112 SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2113}
2114
2115static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective,
2116 kernel_cap_t *inheritable, kernel_cap_t *permitted)
2117{
2118 return avc_has_perm(current_sid(), task_sid_obj(target),
2119 SECCLASS_PROCESS, PROCESS__GETCAP, NULL);
2120}
2121
2122static int selinux_capset(struct cred *new, const struct cred *old,
2123 const kernel_cap_t *effective,
2124 const kernel_cap_t *inheritable,
2125 const kernel_cap_t *permitted)
2126{
2127 return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2128 PROCESS__SETCAP, NULL);
2129}
2130
2131/*
2132 * (This comment used to live with the selinux_task_setuid hook,
2133 * which was removed).
2134 *
2135 * Since setuid only affects the current process, and since the SELinux
2136 * controls are not based on the Linux identity attributes, SELinux does not
2137 * need to control this operation. However, SELinux does control the use of
2138 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2139 */
2140
2141static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2142 int cap, unsigned int opts)
2143{
2144 return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2145}
2146
2147static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb)
2148{
2149 const struct cred *cred = current_cred();
2150 int rc = 0;
2151
2152 if (!sb)
2153 return 0;
2154
2155 switch (cmds) {
2156 case Q_SYNC:
2157 case Q_QUOTAON:
2158 case Q_QUOTAOFF:
2159 case Q_SETINFO:
2160 case Q_SETQUOTA:
2161 case Q_XQUOTAOFF:
2162 case Q_XQUOTAON:
2163 case Q_XSETQLIM:
2164 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2165 break;
2166 case Q_GETFMT:
2167 case Q_GETINFO:
2168 case Q_GETQUOTA:
2169 case Q_XGETQUOTA:
2170 case Q_XGETQSTAT:
2171 case Q_XGETQSTATV:
2172 case Q_XGETNEXTQUOTA:
2173 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2174 break;
2175 default:
2176 rc = 0; /* let the kernel handle invalid cmds */
2177 break;
2178 }
2179 return rc;
2180}
2181
2182static int selinux_quota_on(struct dentry *dentry)
2183{
2184 const struct cred *cred = current_cred();
2185
2186 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2187}
2188
2189static int selinux_syslog(int type)
2190{
2191 switch (type) {
2192 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2193 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2194 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2195 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2196 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2197 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2198 /* Set level of messages printed to console */
2199 case SYSLOG_ACTION_CONSOLE_LEVEL:
2200 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2201 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2202 NULL);
2203 }
2204 /* All other syslog types */
2205 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2206 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2207}
2208
2209/*
2210 * Check permission for allocating a new virtual mapping. Returns
2211 * 0 if permission is granted, negative error code if not.
2212 *
2213 * Do not audit the selinux permission check, as this is applied to all
2214 * processes that allocate mappings.
2215 */
2216static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2217{
2218 return cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2219 CAP_OPT_NOAUDIT, true);
2220}
2221
2222/* binprm security operations */
2223
2224static u32 ptrace_parent_sid(void)
2225{
2226 u32 sid = 0;
2227 struct task_struct *tracer;
2228
2229 rcu_read_lock();
2230 tracer = ptrace_parent(current);
2231 if (tracer)
2232 sid = task_sid_obj(tracer);
2233 rcu_read_unlock();
2234
2235 return sid;
2236}
2237
2238static int check_nnp_nosuid(const struct linux_binprm *bprm,
2239 const struct task_security_struct *old_tsec,
2240 const struct task_security_struct *new_tsec)
2241{
2242 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2243 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2244 int rc;
2245 u32 av;
2246
2247 if (!nnp && !nosuid)
2248 return 0; /* neither NNP nor nosuid */
2249
2250 if (new_tsec->sid == old_tsec->sid)
2251 return 0; /* No change in credentials */
2252
2253 /*
2254 * If the policy enables the nnp_nosuid_transition policy capability,
2255 * then we permit transitions under NNP or nosuid if the
2256 * policy allows the corresponding permission between
2257 * the old and new contexts.
2258 */
2259 if (selinux_policycap_nnp_nosuid_transition()) {
2260 av = 0;
2261 if (nnp)
2262 av |= PROCESS2__NNP_TRANSITION;
2263 if (nosuid)
2264 av |= PROCESS2__NOSUID_TRANSITION;
2265 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2266 SECCLASS_PROCESS2, av, NULL);
2267 if (!rc)
2268 return 0;
2269 }
2270
2271 /*
2272 * We also permit NNP or nosuid transitions to bounded SIDs,
2273 * i.e. SIDs that are guaranteed to only be allowed a subset
2274 * of the permissions of the current SID.
2275 */
2276 rc = security_bounded_transition(old_tsec->sid,
2277 new_tsec->sid);
2278 if (!rc)
2279 return 0;
2280
2281 /*
2282 * On failure, preserve the errno values for NNP vs nosuid.
2283 * NNP: Operation not permitted for caller.
2284 * nosuid: Permission denied to file.
2285 */
2286 if (nnp)
2287 return -EPERM;
2288 return -EACCES;
2289}
2290
2291static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2292{
2293 const struct task_security_struct *old_tsec;
2294 struct task_security_struct *new_tsec;
2295 struct inode_security_struct *isec;
2296 struct common_audit_data ad;
2297 struct inode *inode = file_inode(bprm->file);
2298 int rc;
2299
2300 /* SELinux context only depends on initial program or script and not
2301 * the script interpreter */
2302
2303 old_tsec = selinux_cred(current_cred());
2304 new_tsec = selinux_cred(bprm->cred);
2305 isec = inode_security(inode);
2306
2307 /* Default to the current task SID. */
2308 new_tsec->sid = old_tsec->sid;
2309 new_tsec->osid = old_tsec->sid;
2310
2311 /* Reset fs, key, and sock SIDs on execve. */
2312 new_tsec->create_sid = 0;
2313 new_tsec->keycreate_sid = 0;
2314 new_tsec->sockcreate_sid = 0;
2315
2316 /*
2317 * Before policy is loaded, label any task outside kernel space
2318 * as SECINITSID_INIT, so that any userspace tasks surviving from
2319 * early boot end up with a label different from SECINITSID_KERNEL
2320 * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL).
2321 */
2322 if (!selinux_initialized()) {
2323 new_tsec->sid = SECINITSID_INIT;
2324 /* also clear the exec_sid just in case */
2325 new_tsec->exec_sid = 0;
2326 return 0;
2327 }
2328
2329 if (old_tsec->exec_sid) {
2330 new_tsec->sid = old_tsec->exec_sid;
2331 /* Reset exec SID on execve. */
2332 new_tsec->exec_sid = 0;
2333
2334 /* Fail on NNP or nosuid if not an allowed transition. */
2335 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2336 if (rc)
2337 return rc;
2338 } else {
2339 /* Check for a default transition on this program. */
2340 rc = security_transition_sid(old_tsec->sid,
2341 isec->sid, SECCLASS_PROCESS, NULL,
2342 &new_tsec->sid);
2343 if (rc)
2344 return rc;
2345
2346 /*
2347 * Fallback to old SID on NNP or nosuid if not an allowed
2348 * transition.
2349 */
2350 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2351 if (rc)
2352 new_tsec->sid = old_tsec->sid;
2353 }
2354
2355 ad.type = LSM_AUDIT_DATA_FILE;
2356 ad.u.file = bprm->file;
2357
2358 if (new_tsec->sid == old_tsec->sid) {
2359 rc = avc_has_perm(old_tsec->sid, isec->sid,
2360 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2361 if (rc)
2362 return rc;
2363 } else {
2364 /* Check permissions for the transition. */
2365 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2366 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2367 if (rc)
2368 return rc;
2369
2370 rc = avc_has_perm(new_tsec->sid, isec->sid,
2371 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2372 if (rc)
2373 return rc;
2374
2375 /* Check for shared state */
2376 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2377 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2378 SECCLASS_PROCESS, PROCESS__SHARE,
2379 NULL);
2380 if (rc)
2381 return -EPERM;
2382 }
2383
2384 /* Make sure that anyone attempting to ptrace over a task that
2385 * changes its SID has the appropriate permit */
2386 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2387 u32 ptsid = ptrace_parent_sid();
2388 if (ptsid != 0) {
2389 rc = avc_has_perm(ptsid, new_tsec->sid,
2390 SECCLASS_PROCESS,
2391 PROCESS__PTRACE, NULL);
2392 if (rc)
2393 return -EPERM;
2394 }
2395 }
2396
2397 /* Clear any possibly unsafe personality bits on exec: */
2398 bprm->per_clear |= PER_CLEAR_ON_SETID;
2399
2400 /* Enable secure mode for SIDs transitions unless
2401 the noatsecure permission is granted between
2402 the two SIDs, i.e. ahp returns 0. */
2403 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2404 SECCLASS_PROCESS, PROCESS__NOATSECURE,
2405 NULL);
2406 bprm->secureexec |= !!rc;
2407 }
2408
2409 return 0;
2410}
2411
2412static int match_file(const void *p, struct file *file, unsigned fd)
2413{
2414 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2415}
2416
2417/* Derived from fs/exec.c:flush_old_files. */
2418static inline void flush_unauthorized_files(const struct cred *cred,
2419 struct files_struct *files)
2420{
2421 struct file *file, *devnull = NULL;
2422 struct tty_struct *tty;
2423 int drop_tty = 0;
2424 unsigned n;
2425
2426 tty = get_current_tty();
2427 if (tty) {
2428 spin_lock(&tty->files_lock);
2429 if (!list_empty(&tty->tty_files)) {
2430 struct tty_file_private *file_priv;
2431
2432 /* Revalidate access to controlling tty.
2433 Use file_path_has_perm on the tty path directly
2434 rather than using file_has_perm, as this particular
2435 open file may belong to another process and we are
2436 only interested in the inode-based check here. */
2437 file_priv = list_first_entry(&tty->tty_files,
2438 struct tty_file_private, list);
2439 file = file_priv->file;
2440 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2441 drop_tty = 1;
2442 }
2443 spin_unlock(&tty->files_lock);
2444 tty_kref_put(tty);
2445 }
2446 /* Reset controlling tty. */
2447 if (drop_tty)
2448 no_tty();
2449
2450 /* Revalidate access to inherited open files. */
2451 n = iterate_fd(files, 0, match_file, cred);
2452 if (!n) /* none found? */
2453 return;
2454
2455 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2456 if (IS_ERR(devnull))
2457 devnull = NULL;
2458 /* replace all the matching ones with this */
2459 do {
2460 replace_fd(n - 1, devnull, 0);
2461 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2462 if (devnull)
2463 fput(devnull);
2464}
2465
2466/*
2467 * Prepare a process for imminent new credential changes due to exec
2468 */
2469static void selinux_bprm_committing_creds(const struct linux_binprm *bprm)
2470{
2471 struct task_security_struct *new_tsec;
2472 struct rlimit *rlim, *initrlim;
2473 int rc, i;
2474
2475 new_tsec = selinux_cred(bprm->cred);
2476 if (new_tsec->sid == new_tsec->osid)
2477 return;
2478
2479 /* Close files for which the new task SID is not authorized. */
2480 flush_unauthorized_files(bprm->cred, current->files);
2481
2482 /* Always clear parent death signal on SID transitions. */
2483 current->pdeath_signal = 0;
2484
2485 /* Check whether the new SID can inherit resource limits from the old
2486 * SID. If not, reset all soft limits to the lower of the current
2487 * task's hard limit and the init task's soft limit.
2488 *
2489 * Note that the setting of hard limits (even to lower them) can be
2490 * controlled by the setrlimit check. The inclusion of the init task's
2491 * soft limit into the computation is to avoid resetting soft limits
2492 * higher than the default soft limit for cases where the default is
2493 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2494 */
2495 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2496 PROCESS__RLIMITINH, NULL);
2497 if (rc) {
2498 /* protect against do_prlimit() */
2499 task_lock(current);
2500 for (i = 0; i < RLIM_NLIMITS; i++) {
2501 rlim = current->signal->rlim + i;
2502 initrlim = init_task.signal->rlim + i;
2503 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2504 }
2505 task_unlock(current);
2506 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2507 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2508 }
2509}
2510
2511/*
2512 * Clean up the process immediately after the installation of new credentials
2513 * due to exec
2514 */
2515static void selinux_bprm_committed_creds(const struct linux_binprm *bprm)
2516{
2517 const struct task_security_struct *tsec = selinux_cred(current_cred());
2518 u32 osid, sid;
2519 int rc;
2520
2521 osid = tsec->osid;
2522 sid = tsec->sid;
2523
2524 if (sid == osid)
2525 return;
2526
2527 /* Check whether the new SID can inherit signal state from the old SID.
2528 * If not, clear itimers to avoid subsequent signal generation and
2529 * flush and unblock signals.
2530 *
2531 * This must occur _after_ the task SID has been updated so that any
2532 * kill done after the flush will be checked against the new SID.
2533 */
2534 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2535 if (rc) {
2536 clear_itimer();
2537
2538 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock);
2539 if (!fatal_signal_pending(current)) {
2540 flush_sigqueue(¤t->pending);
2541 flush_sigqueue(¤t->signal->shared_pending);
2542 flush_signal_handlers(current, 1);
2543 sigemptyset(¤t->blocked);
2544 recalc_sigpending();
2545 }
2546 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock);
2547 }
2548
2549 /* Wake up the parent if it is waiting so that it can recheck
2550 * wait permission to the new task SID. */
2551 read_lock(&tasklist_lock);
2552 __wake_up_parent(current, unrcu_pointer(current->real_parent));
2553 read_unlock(&tasklist_lock);
2554}
2555
2556/* superblock security operations */
2557
2558static int selinux_sb_alloc_security(struct super_block *sb)
2559{
2560 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2561
2562 mutex_init(&sbsec->lock);
2563 INIT_LIST_HEAD(&sbsec->isec_head);
2564 spin_lock_init(&sbsec->isec_lock);
2565 sbsec->sid = SECINITSID_UNLABELED;
2566 sbsec->def_sid = SECINITSID_FILE;
2567 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2568
2569 return 0;
2570}
2571
2572static inline int opt_len(const char *s)
2573{
2574 bool open_quote = false;
2575 int len;
2576 char c;
2577
2578 for (len = 0; (c = s[len]) != '\0'; len++) {
2579 if (c == '"')
2580 open_quote = !open_quote;
2581 if (c == ',' && !open_quote)
2582 break;
2583 }
2584 return len;
2585}
2586
2587static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2588{
2589 char *from = options;
2590 char *to = options;
2591 bool first = true;
2592 int rc;
2593
2594 while (1) {
2595 int len = opt_len(from);
2596 int token;
2597 char *arg = NULL;
2598
2599 token = match_opt_prefix(from, len, &arg);
2600
2601 if (token != Opt_error) {
2602 char *p, *q;
2603
2604 /* strip quotes */
2605 if (arg) {
2606 for (p = q = arg; p < from + len; p++) {
2607 char c = *p;
2608 if (c != '"')
2609 *q++ = c;
2610 }
2611 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2612 if (!arg) {
2613 rc = -ENOMEM;
2614 goto free_opt;
2615 }
2616 }
2617 rc = selinux_add_opt(token, arg, mnt_opts);
2618 kfree(arg);
2619 arg = NULL;
2620 if (unlikely(rc)) {
2621 goto free_opt;
2622 }
2623 } else {
2624 if (!first) { // copy with preceding comma
2625 from--;
2626 len++;
2627 }
2628 if (to != from)
2629 memmove(to, from, len);
2630 to += len;
2631 first = false;
2632 }
2633 if (!from[len])
2634 break;
2635 from += len + 1;
2636 }
2637 *to = '\0';
2638 return 0;
2639
2640free_opt:
2641 if (*mnt_opts) {
2642 selinux_free_mnt_opts(*mnt_opts);
2643 *mnt_opts = NULL;
2644 }
2645 return rc;
2646}
2647
2648static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
2649{
2650 struct selinux_mnt_opts *opts = mnt_opts;
2651 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2652
2653 /*
2654 * Superblock not initialized (i.e. no options) - reject if any
2655 * options specified, otherwise accept.
2656 */
2657 if (!(sbsec->flags & SE_SBINITIALIZED))
2658 return opts ? 1 : 0;
2659
2660 /*
2661 * Superblock initialized and no options specified - reject if
2662 * superblock has any options set, otherwise accept.
2663 */
2664 if (!opts)
2665 return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2666
2667 if (opts->fscontext_sid) {
2668 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2669 opts->fscontext_sid))
2670 return 1;
2671 }
2672 if (opts->context_sid) {
2673 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2674 opts->context_sid))
2675 return 1;
2676 }
2677 if (opts->rootcontext_sid) {
2678 struct inode_security_struct *root_isec;
2679
2680 root_isec = backing_inode_security(sb->s_root);
2681 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2682 opts->rootcontext_sid))
2683 return 1;
2684 }
2685 if (opts->defcontext_sid) {
2686 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2687 opts->defcontext_sid))
2688 return 1;
2689 }
2690 return 0;
2691}
2692
2693static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2694{
2695 struct selinux_mnt_opts *opts = mnt_opts;
2696 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2697
2698 if (!(sbsec->flags & SE_SBINITIALIZED))
2699 return 0;
2700
2701 if (!opts)
2702 return 0;
2703
2704 if (opts->fscontext_sid) {
2705 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2706 opts->fscontext_sid))
2707 goto out_bad_option;
2708 }
2709 if (opts->context_sid) {
2710 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2711 opts->context_sid))
2712 goto out_bad_option;
2713 }
2714 if (opts->rootcontext_sid) {
2715 struct inode_security_struct *root_isec;
2716 root_isec = backing_inode_security(sb->s_root);
2717 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2718 opts->rootcontext_sid))
2719 goto out_bad_option;
2720 }
2721 if (opts->defcontext_sid) {
2722 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2723 opts->defcontext_sid))
2724 goto out_bad_option;
2725 }
2726 return 0;
2727
2728out_bad_option:
2729 pr_warn("SELinux: unable to change security options "
2730 "during remount (dev %s, type=%s)\n", sb->s_id,
2731 sb->s_type->name);
2732 return -EINVAL;
2733}
2734
2735static int selinux_sb_kern_mount(const struct super_block *sb)
2736{
2737 const struct cred *cred = current_cred();
2738 struct common_audit_data ad;
2739
2740 ad.type = LSM_AUDIT_DATA_DENTRY;
2741 ad.u.dentry = sb->s_root;
2742 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2743}
2744
2745static int selinux_sb_statfs(struct dentry *dentry)
2746{
2747 const struct cred *cred = current_cred();
2748 struct common_audit_data ad;
2749
2750 ad.type = LSM_AUDIT_DATA_DENTRY;
2751 ad.u.dentry = dentry->d_sb->s_root;
2752 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2753}
2754
2755static int selinux_mount(const char *dev_name,
2756 const struct path *path,
2757 const char *type,
2758 unsigned long flags,
2759 void *data)
2760{
2761 const struct cred *cred = current_cred();
2762
2763 if (flags & MS_REMOUNT)
2764 return superblock_has_perm(cred, path->dentry->d_sb,
2765 FILESYSTEM__REMOUNT, NULL);
2766 else
2767 return path_has_perm(cred, path, FILE__MOUNTON);
2768}
2769
2770static int selinux_move_mount(const struct path *from_path,
2771 const struct path *to_path)
2772{
2773 const struct cred *cred = current_cred();
2774
2775 return path_has_perm(cred, to_path, FILE__MOUNTON);
2776}
2777
2778static int selinux_umount(struct vfsmount *mnt, int flags)
2779{
2780 const struct cred *cred = current_cred();
2781
2782 return superblock_has_perm(cred, mnt->mnt_sb,
2783 FILESYSTEM__UNMOUNT, NULL);
2784}
2785
2786static int selinux_fs_context_submount(struct fs_context *fc,
2787 struct super_block *reference)
2788{
2789 const struct superblock_security_struct *sbsec = selinux_superblock(reference);
2790 struct selinux_mnt_opts *opts;
2791
2792 /*
2793 * Ensure that fc->security remains NULL when no options are set
2794 * as expected by selinux_set_mnt_opts().
2795 */
2796 if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT)))
2797 return 0;
2798
2799 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
2800 if (!opts)
2801 return -ENOMEM;
2802
2803 if (sbsec->flags & FSCONTEXT_MNT)
2804 opts->fscontext_sid = sbsec->sid;
2805 if (sbsec->flags & CONTEXT_MNT)
2806 opts->context_sid = sbsec->mntpoint_sid;
2807 if (sbsec->flags & DEFCONTEXT_MNT)
2808 opts->defcontext_sid = sbsec->def_sid;
2809 fc->security = opts;
2810 return 0;
2811}
2812
2813static int selinux_fs_context_dup(struct fs_context *fc,
2814 struct fs_context *src_fc)
2815{
2816 const struct selinux_mnt_opts *src = src_fc->security;
2817
2818 if (!src)
2819 return 0;
2820
2821 fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL);
2822 return fc->security ? 0 : -ENOMEM;
2823}
2824
2825static const struct fs_parameter_spec selinux_fs_parameters[] = {
2826 fsparam_string(CONTEXT_STR, Opt_context),
2827 fsparam_string(DEFCONTEXT_STR, Opt_defcontext),
2828 fsparam_string(FSCONTEXT_STR, Opt_fscontext),
2829 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2830 fsparam_flag (SECLABEL_STR, Opt_seclabel),
2831 {}
2832};
2833
2834static int selinux_fs_context_parse_param(struct fs_context *fc,
2835 struct fs_parameter *param)
2836{
2837 struct fs_parse_result result;
2838 int opt;
2839
2840 opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2841 if (opt < 0)
2842 return opt;
2843
2844 return selinux_add_opt(opt, param->string, &fc->security);
2845}
2846
2847/* inode security operations */
2848
2849static int selinux_inode_alloc_security(struct inode *inode)
2850{
2851 struct inode_security_struct *isec = selinux_inode(inode);
2852 u32 sid = current_sid();
2853
2854 spin_lock_init(&isec->lock);
2855 INIT_LIST_HEAD(&isec->list);
2856 isec->inode = inode;
2857 isec->sid = SECINITSID_UNLABELED;
2858 isec->sclass = SECCLASS_FILE;
2859 isec->task_sid = sid;
2860 isec->initialized = LABEL_INVALID;
2861
2862 return 0;
2863}
2864
2865static void selinux_inode_free_security(struct inode *inode)
2866{
2867 inode_free_security(inode);
2868}
2869
2870static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2871 const struct qstr *name,
2872 const char **xattr_name, void **ctx,
2873 u32 *ctxlen)
2874{
2875 u32 newsid;
2876 int rc;
2877
2878 rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2879 d_inode(dentry->d_parent), name,
2880 inode_mode_to_security_class(mode),
2881 &newsid);
2882 if (rc)
2883 return rc;
2884
2885 if (xattr_name)
2886 *xattr_name = XATTR_NAME_SELINUX;
2887
2888 return security_sid_to_context(newsid, (char **)ctx,
2889 ctxlen);
2890}
2891
2892static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2893 struct qstr *name,
2894 const struct cred *old,
2895 struct cred *new)
2896{
2897 u32 newsid;
2898 int rc;
2899 struct task_security_struct *tsec;
2900
2901 rc = selinux_determine_inode_label(selinux_cred(old),
2902 d_inode(dentry->d_parent), name,
2903 inode_mode_to_security_class(mode),
2904 &newsid);
2905 if (rc)
2906 return rc;
2907
2908 tsec = selinux_cred(new);
2909 tsec->create_sid = newsid;
2910 return 0;
2911}
2912
2913static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2914 const struct qstr *qstr,
2915 struct xattr *xattrs, int *xattr_count)
2916{
2917 const struct task_security_struct *tsec = selinux_cred(current_cred());
2918 struct superblock_security_struct *sbsec;
2919 struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count);
2920 u32 newsid, clen;
2921 u16 newsclass;
2922 int rc;
2923 char *context;
2924
2925 sbsec = selinux_superblock(dir->i_sb);
2926
2927 newsid = tsec->create_sid;
2928 newsclass = inode_mode_to_security_class(inode->i_mode);
2929 rc = selinux_determine_inode_label(tsec, dir, qstr, newsclass, &newsid);
2930 if (rc)
2931 return rc;
2932
2933 /* Possibly defer initialization to selinux_complete_init. */
2934 if (sbsec->flags & SE_SBINITIALIZED) {
2935 struct inode_security_struct *isec = selinux_inode(inode);
2936 isec->sclass = newsclass;
2937 isec->sid = newsid;
2938 isec->initialized = LABEL_INITIALIZED;
2939 }
2940
2941 if (!selinux_initialized() ||
2942 !(sbsec->flags & SBLABEL_MNT))
2943 return -EOPNOTSUPP;
2944
2945 if (xattr) {
2946 rc = security_sid_to_context_force(newsid,
2947 &context, &clen);
2948 if (rc)
2949 return rc;
2950 xattr->value = context;
2951 xattr->value_len = clen;
2952 xattr->name = XATTR_SELINUX_SUFFIX;
2953 }
2954
2955 return 0;
2956}
2957
2958static int selinux_inode_init_security_anon(struct inode *inode,
2959 const struct qstr *name,
2960 const struct inode *context_inode)
2961{
2962 u32 sid = current_sid();
2963 struct common_audit_data ad;
2964 struct inode_security_struct *isec;
2965 int rc;
2966
2967 if (unlikely(!selinux_initialized()))
2968 return 0;
2969
2970 isec = selinux_inode(inode);
2971
2972 /*
2973 * We only get here once per ephemeral inode. The inode has
2974 * been initialized via inode_alloc_security but is otherwise
2975 * untouched.
2976 */
2977
2978 if (context_inode) {
2979 struct inode_security_struct *context_isec =
2980 selinux_inode(context_inode);
2981 if (context_isec->initialized != LABEL_INITIALIZED) {
2982 pr_err("SELinux: context_inode is not initialized\n");
2983 return -EACCES;
2984 }
2985
2986 isec->sclass = context_isec->sclass;
2987 isec->sid = context_isec->sid;
2988 } else {
2989 isec->sclass = SECCLASS_ANON_INODE;
2990 rc = security_transition_sid(
2991 sid, sid,
2992 isec->sclass, name, &isec->sid);
2993 if (rc)
2994 return rc;
2995 }
2996
2997 isec->initialized = LABEL_INITIALIZED;
2998 /*
2999 * Now that we've initialized security, check whether we're
3000 * allowed to actually create this type of anonymous inode.
3001 */
3002
3003 ad.type = LSM_AUDIT_DATA_ANONINODE;
3004 ad.u.anonclass = name ? (const char *)name->name : "?";
3005
3006 return avc_has_perm(sid,
3007 isec->sid,
3008 isec->sclass,
3009 FILE__CREATE,
3010 &ad);
3011}
3012
3013static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3014{
3015 return may_create(dir, dentry, SECCLASS_FILE);
3016}
3017
3018static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3019{
3020 return may_link(dir, old_dentry, MAY_LINK);
3021}
3022
3023static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3024{
3025 return may_link(dir, dentry, MAY_UNLINK);
3026}
3027
3028static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3029{
3030 return may_create(dir, dentry, SECCLASS_LNK_FILE);
3031}
3032
3033static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3034{
3035 return may_create(dir, dentry, SECCLASS_DIR);
3036}
3037
3038static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3039{
3040 return may_link(dir, dentry, MAY_RMDIR);
3041}
3042
3043static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3044{
3045 return may_create(dir, dentry, inode_mode_to_security_class(mode));
3046}
3047
3048static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3049 struct inode *new_inode, struct dentry *new_dentry)
3050{
3051 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3052}
3053
3054static int selinux_inode_readlink(struct dentry *dentry)
3055{
3056 const struct cred *cred = current_cred();
3057
3058 return dentry_has_perm(cred, dentry, FILE__READ);
3059}
3060
3061static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3062 bool rcu)
3063{
3064 struct common_audit_data ad;
3065 struct inode_security_struct *isec;
3066 u32 sid = current_sid();
3067
3068 ad.type = LSM_AUDIT_DATA_DENTRY;
3069 ad.u.dentry = dentry;
3070 isec = inode_security_rcu(inode, rcu);
3071 if (IS_ERR(isec))
3072 return PTR_ERR(isec);
3073
3074 return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad);
3075}
3076
3077static noinline int audit_inode_permission(struct inode *inode,
3078 u32 perms, u32 audited, u32 denied,
3079 int result)
3080{
3081 struct common_audit_data ad;
3082 struct inode_security_struct *isec = selinux_inode(inode);
3083
3084 ad.type = LSM_AUDIT_DATA_INODE;
3085 ad.u.inode = inode;
3086
3087 return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3088 audited, denied, result, &ad);
3089}
3090
3091static int selinux_inode_permission(struct inode *inode, int mask)
3092{
3093 u32 perms;
3094 bool from_access;
3095 bool no_block = mask & MAY_NOT_BLOCK;
3096 struct inode_security_struct *isec;
3097 u32 sid = current_sid();
3098 struct av_decision avd;
3099 int rc, rc2;
3100 u32 audited, denied;
3101
3102 from_access = mask & MAY_ACCESS;
3103 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3104
3105 /* No permission to check. Existence test. */
3106 if (!mask)
3107 return 0;
3108
3109 if (unlikely(IS_PRIVATE(inode)))
3110 return 0;
3111
3112 perms = file_mask_to_av(inode->i_mode, mask);
3113
3114 isec = inode_security_rcu(inode, no_block);
3115 if (IS_ERR(isec))
3116 return PTR_ERR(isec);
3117
3118 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0,
3119 &avd);
3120 audited = avc_audit_required(perms, &avd, rc,
3121 from_access ? FILE__AUDIT_ACCESS : 0,
3122 &denied);
3123 if (likely(!audited))
3124 return rc;
3125
3126 rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3127 if (rc2)
3128 return rc2;
3129 return rc;
3130}
3131
3132static int selinux_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
3133 struct iattr *iattr)
3134{
3135 const struct cred *cred = current_cred();
3136 struct inode *inode = d_backing_inode(dentry);
3137 unsigned int ia_valid = iattr->ia_valid;
3138 __u32 av = FILE__WRITE;
3139
3140 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3141 if (ia_valid & ATTR_FORCE) {
3142 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3143 ATTR_FORCE);
3144 if (!ia_valid)
3145 return 0;
3146 }
3147
3148 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3149 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3150 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3151
3152 if (selinux_policycap_openperm() &&
3153 inode->i_sb->s_magic != SOCKFS_MAGIC &&
3154 (ia_valid & ATTR_SIZE) &&
3155 !(ia_valid & ATTR_FILE))
3156 av |= FILE__OPEN;
3157
3158 return dentry_has_perm(cred, dentry, av);
3159}
3160
3161static int selinux_inode_getattr(const struct path *path)
3162{
3163 return path_has_perm(current_cred(), path, FILE__GETATTR);
3164}
3165
3166static bool has_cap_mac_admin(bool audit)
3167{
3168 const struct cred *cred = current_cred();
3169 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3170
3171 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3172 return false;
3173 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3174 return false;
3175 return true;
3176}
3177
3178/**
3179 * selinux_inode_xattr_skipcap - Skip the xattr capability checks?
3180 * @name: name of the xattr
3181 *
3182 * Returns 1 to indicate that SELinux "owns" the access control rights to xattrs
3183 * named @name; the LSM layer should avoid enforcing any traditional
3184 * capability based access controls on this xattr. Returns 0 to indicate that
3185 * SELinux does not "own" the access control rights to xattrs named @name and is
3186 * deferring to the LSM layer for further access controls, including capability
3187 * based controls.
3188 */
3189static int selinux_inode_xattr_skipcap(const char *name)
3190{
3191 /* require capability check if not a selinux xattr */
3192 return !strcmp(name, XATTR_NAME_SELINUX);
3193}
3194
3195static int selinux_inode_setxattr(struct mnt_idmap *idmap,
3196 struct dentry *dentry, const char *name,
3197 const void *value, size_t size, int flags)
3198{
3199 struct inode *inode = d_backing_inode(dentry);
3200 struct inode_security_struct *isec;
3201 struct superblock_security_struct *sbsec;
3202 struct common_audit_data ad;
3203 u32 newsid, sid = current_sid();
3204 int rc = 0;
3205
3206 /* if not a selinux xattr, only check the ordinary setattr perm */
3207 if (strcmp(name, XATTR_NAME_SELINUX))
3208 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3209
3210 if (!selinux_initialized())
3211 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM);
3212
3213 sbsec = selinux_superblock(inode->i_sb);
3214 if (!(sbsec->flags & SBLABEL_MNT))
3215 return -EOPNOTSUPP;
3216
3217 if (!inode_owner_or_capable(idmap, inode))
3218 return -EPERM;
3219
3220 ad.type = LSM_AUDIT_DATA_DENTRY;
3221 ad.u.dentry = dentry;
3222
3223 isec = backing_inode_security(dentry);
3224 rc = avc_has_perm(sid, isec->sid, isec->sclass,
3225 FILE__RELABELFROM, &ad);
3226 if (rc)
3227 return rc;
3228
3229 rc = security_context_to_sid(value, size, &newsid,
3230 GFP_KERNEL);
3231 if (rc == -EINVAL) {
3232 if (!has_cap_mac_admin(true)) {
3233 struct audit_buffer *ab;
3234 size_t audit_size;
3235
3236 /* We strip a nul only if it is at the end, otherwise the
3237 * context contains a nul and we should audit that */
3238 if (value) {
3239 const char *str = value;
3240
3241 if (str[size - 1] == '\0')
3242 audit_size = size - 1;
3243 else
3244 audit_size = size;
3245 } else {
3246 audit_size = 0;
3247 }
3248 ab = audit_log_start(audit_context(),
3249 GFP_ATOMIC, AUDIT_SELINUX_ERR);
3250 if (!ab)
3251 return rc;
3252 audit_log_format(ab, "op=setxattr invalid_context=");
3253 audit_log_n_untrustedstring(ab, value, audit_size);
3254 audit_log_end(ab);
3255
3256 return rc;
3257 }
3258 rc = security_context_to_sid_force(value,
3259 size, &newsid);
3260 }
3261 if (rc)
3262 return rc;
3263
3264 rc = avc_has_perm(sid, newsid, isec->sclass,
3265 FILE__RELABELTO, &ad);
3266 if (rc)
3267 return rc;
3268
3269 rc = security_validate_transition(isec->sid, newsid,
3270 sid, isec->sclass);
3271 if (rc)
3272 return rc;
3273
3274 return avc_has_perm(newsid,
3275 sbsec->sid,
3276 SECCLASS_FILESYSTEM,
3277 FILESYSTEM__ASSOCIATE,
3278 &ad);
3279}
3280
3281static int selinux_inode_set_acl(struct mnt_idmap *idmap,
3282 struct dentry *dentry, const char *acl_name,
3283 struct posix_acl *kacl)
3284{
3285 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3286}
3287
3288static int selinux_inode_get_acl(struct mnt_idmap *idmap,
3289 struct dentry *dentry, const char *acl_name)
3290{
3291 return dentry_has_perm(current_cred(), dentry, FILE__GETATTR);
3292}
3293
3294static int selinux_inode_remove_acl(struct mnt_idmap *idmap,
3295 struct dentry *dentry, const char *acl_name)
3296{
3297 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3298}
3299
3300static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3301 const void *value, size_t size,
3302 int flags)
3303{
3304 struct inode *inode = d_backing_inode(dentry);
3305 struct inode_security_struct *isec;
3306 u32 newsid;
3307 int rc;
3308
3309 if (strcmp(name, XATTR_NAME_SELINUX)) {
3310 /* Not an attribute we recognize, so nothing to do. */
3311 return;
3312 }
3313
3314 if (!selinux_initialized()) {
3315 /* If we haven't even been initialized, then we can't validate
3316 * against a policy, so leave the label as invalid. It may
3317 * resolve to a valid label on the next revalidation try if
3318 * we've since initialized.
3319 */
3320 return;
3321 }
3322
3323 rc = security_context_to_sid_force(value, size,
3324 &newsid);
3325 if (rc) {
3326 pr_err("SELinux: unable to map context to SID"
3327 "for (%s, %lu), rc=%d\n",
3328 inode->i_sb->s_id, inode->i_ino, -rc);
3329 return;
3330 }
3331
3332 isec = backing_inode_security(dentry);
3333 spin_lock(&isec->lock);
3334 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3335 isec->sid = newsid;
3336 isec->initialized = LABEL_INITIALIZED;
3337 spin_unlock(&isec->lock);
3338}
3339
3340static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3341{
3342 const struct cred *cred = current_cred();
3343
3344 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3345}
3346
3347static int selinux_inode_listxattr(struct dentry *dentry)
3348{
3349 const struct cred *cred = current_cred();
3350
3351 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3352}
3353
3354static int selinux_inode_removexattr(struct mnt_idmap *idmap,
3355 struct dentry *dentry, const char *name)
3356{
3357 /* if not a selinux xattr, only check the ordinary setattr perm */
3358 if (strcmp(name, XATTR_NAME_SELINUX))
3359 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3360
3361 if (!selinux_initialized())
3362 return 0;
3363
3364 /* No one is allowed to remove a SELinux security label.
3365 You can change the label, but all data must be labeled. */
3366 return -EACCES;
3367}
3368
3369static int selinux_path_notify(const struct path *path, u64 mask,
3370 unsigned int obj_type)
3371{
3372 int ret;
3373 u32 perm;
3374
3375 struct common_audit_data ad;
3376
3377 ad.type = LSM_AUDIT_DATA_PATH;
3378 ad.u.path = *path;
3379
3380 /*
3381 * Set permission needed based on the type of mark being set.
3382 * Performs an additional check for sb watches.
3383 */
3384 switch (obj_type) {
3385 case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3386 perm = FILE__WATCH_MOUNT;
3387 break;
3388 case FSNOTIFY_OBJ_TYPE_SB:
3389 perm = FILE__WATCH_SB;
3390 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3391 FILESYSTEM__WATCH, &ad);
3392 if (ret)
3393 return ret;
3394 break;
3395 case FSNOTIFY_OBJ_TYPE_INODE:
3396 perm = FILE__WATCH;
3397 break;
3398 default:
3399 return -EINVAL;
3400 }
3401
3402 /* blocking watches require the file:watch_with_perm permission */
3403 if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3404 perm |= FILE__WATCH_WITH_PERM;
3405
3406 /* watches on read-like events need the file:watch_reads permission */
3407 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3408 perm |= FILE__WATCH_READS;
3409
3410 return path_has_perm(current_cred(), path, perm);
3411}
3412
3413/*
3414 * Copy the inode security context value to the user.
3415 *
3416 * Permission check is handled by selinux_inode_getxattr hook.
3417 */
3418static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3419 struct inode *inode, const char *name,
3420 void **buffer, bool alloc)
3421{
3422 u32 size;
3423 int error;
3424 char *context = NULL;
3425 struct inode_security_struct *isec;
3426
3427 /*
3428 * If we're not initialized yet, then we can't validate contexts, so
3429 * just let vfs_getxattr fall back to using the on-disk xattr.
3430 */
3431 if (!selinux_initialized() ||
3432 strcmp(name, XATTR_SELINUX_SUFFIX))
3433 return -EOPNOTSUPP;
3434
3435 /*
3436 * If the caller has CAP_MAC_ADMIN, then get the raw context
3437 * value even if it is not defined by current policy; otherwise,
3438 * use the in-core value under current policy.
3439 * Use the non-auditing forms of the permission checks since
3440 * getxattr may be called by unprivileged processes commonly
3441 * and lack of permission just means that we fall back to the
3442 * in-core context value, not a denial.
3443 */
3444 isec = inode_security(inode);
3445 if (has_cap_mac_admin(false))
3446 error = security_sid_to_context_force(isec->sid, &context,
3447 &size);
3448 else
3449 error = security_sid_to_context(isec->sid,
3450 &context, &size);
3451 if (error)
3452 return error;
3453 error = size;
3454 if (alloc) {
3455 *buffer = context;
3456 goto out_nofree;
3457 }
3458 kfree(context);
3459out_nofree:
3460 return error;
3461}
3462
3463static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3464 const void *value, size_t size, int flags)
3465{
3466 struct inode_security_struct *isec = inode_security_novalidate(inode);
3467 struct superblock_security_struct *sbsec;
3468 u32 newsid;
3469 int rc;
3470
3471 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3472 return -EOPNOTSUPP;
3473
3474 sbsec = selinux_superblock(inode->i_sb);
3475 if (!(sbsec->flags & SBLABEL_MNT))
3476 return -EOPNOTSUPP;
3477
3478 if (!value || !size)
3479 return -EACCES;
3480
3481 rc = security_context_to_sid(value, size, &newsid,
3482 GFP_KERNEL);
3483 if (rc)
3484 return rc;
3485
3486 spin_lock(&isec->lock);
3487 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3488 isec->sid = newsid;
3489 isec->initialized = LABEL_INITIALIZED;
3490 spin_unlock(&isec->lock);
3491 return 0;
3492}
3493
3494static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3495{
3496 const int len = sizeof(XATTR_NAME_SELINUX);
3497
3498 if (!selinux_initialized())
3499 return 0;
3500
3501 if (buffer && len <= buffer_size)
3502 memcpy(buffer, XATTR_NAME_SELINUX, len);
3503 return len;
3504}
3505
3506static void selinux_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop)
3507{
3508 struct inode_security_struct *isec = inode_security_novalidate(inode);
3509
3510 prop->selinux.secid = isec->sid;
3511}
3512
3513static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3514{
3515 struct lsm_prop prop;
3516 struct task_security_struct *tsec;
3517 struct cred *new_creds = *new;
3518
3519 if (new_creds == NULL) {
3520 new_creds = prepare_creds();
3521 if (!new_creds)
3522 return -ENOMEM;
3523 }
3524
3525 tsec = selinux_cred(new_creds);
3526 /* Get label from overlay inode and set it in create_sid */
3527 selinux_inode_getlsmprop(d_inode(src), &prop);
3528 tsec->create_sid = prop.selinux.secid;
3529 *new = new_creds;
3530 return 0;
3531}
3532
3533static int selinux_inode_copy_up_xattr(struct dentry *dentry, const char *name)
3534{
3535 /* The copy_up hook above sets the initial context on an inode, but we
3536 * don't then want to overwrite it by blindly copying all the lower
3537 * xattrs up. Instead, filter out SELinux-related xattrs following
3538 * policy load.
3539 */
3540 if (selinux_initialized() && !strcmp(name, XATTR_NAME_SELINUX))
3541 return -ECANCELED; /* Discard */
3542 /*
3543 * Any other attribute apart from SELINUX is not claimed, supported
3544 * by selinux.
3545 */
3546 return -EOPNOTSUPP;
3547}
3548
3549/* kernfs node operations */
3550
3551static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3552 struct kernfs_node *kn)
3553{
3554 const struct task_security_struct *tsec = selinux_cred(current_cred());
3555 u32 parent_sid, newsid, clen;
3556 int rc;
3557 char *context;
3558
3559 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3560 if (rc == -ENODATA)
3561 return 0;
3562 else if (rc < 0)
3563 return rc;
3564
3565 clen = (u32)rc;
3566 context = kmalloc(clen, GFP_KERNEL);
3567 if (!context)
3568 return -ENOMEM;
3569
3570 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3571 if (rc < 0) {
3572 kfree(context);
3573 return rc;
3574 }
3575
3576 rc = security_context_to_sid(context, clen, &parent_sid,
3577 GFP_KERNEL);
3578 kfree(context);
3579 if (rc)
3580 return rc;
3581
3582 if (tsec->create_sid) {
3583 newsid = tsec->create_sid;
3584 } else {
3585 u16 secclass = inode_mode_to_security_class(kn->mode);
3586 struct qstr q;
3587
3588 q.name = kn->name;
3589 q.hash_len = hashlen_string(kn_dir, kn->name);
3590
3591 rc = security_transition_sid(tsec->sid,
3592 parent_sid, secclass, &q,
3593 &newsid);
3594 if (rc)
3595 return rc;
3596 }
3597
3598 rc = security_sid_to_context_force(newsid,
3599 &context, &clen);
3600 if (rc)
3601 return rc;
3602
3603 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3604 XATTR_CREATE);
3605 kfree(context);
3606 return rc;
3607}
3608
3609
3610/* file security operations */
3611
3612static int selinux_revalidate_file_permission(struct file *file, int mask)
3613{
3614 const struct cred *cred = current_cred();
3615 struct inode *inode = file_inode(file);
3616
3617 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3618 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3619 mask |= MAY_APPEND;
3620
3621 return file_has_perm(cred, file,
3622 file_mask_to_av(inode->i_mode, mask));
3623}
3624
3625static int selinux_file_permission(struct file *file, int mask)
3626{
3627 struct inode *inode = file_inode(file);
3628 struct file_security_struct *fsec = selinux_file(file);
3629 struct inode_security_struct *isec;
3630 u32 sid = current_sid();
3631
3632 if (!mask)
3633 /* No permission to check. Existence test. */
3634 return 0;
3635
3636 isec = inode_security(inode);
3637 if (sid == fsec->sid && fsec->isid == isec->sid &&
3638 fsec->pseqno == avc_policy_seqno())
3639 /* No change since file_open check. */
3640 return 0;
3641
3642 return selinux_revalidate_file_permission(file, mask);
3643}
3644
3645static int selinux_file_alloc_security(struct file *file)
3646{
3647 struct file_security_struct *fsec = selinux_file(file);
3648 u32 sid = current_sid();
3649
3650 fsec->sid = sid;
3651 fsec->fown_sid = sid;
3652
3653 return 0;
3654}
3655
3656/*
3657 * Check whether a task has the ioctl permission and cmd
3658 * operation to an inode.
3659 */
3660static int ioctl_has_perm(const struct cred *cred, struct file *file,
3661 u32 requested, u16 cmd)
3662{
3663 struct common_audit_data ad;
3664 struct file_security_struct *fsec = selinux_file(file);
3665 struct inode *inode = file_inode(file);
3666 struct inode_security_struct *isec;
3667 struct lsm_ioctlop_audit ioctl;
3668 u32 ssid = cred_sid(cred);
3669 int rc;
3670 u8 driver = cmd >> 8;
3671 u8 xperm = cmd & 0xff;
3672
3673 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3674 ad.u.op = &ioctl;
3675 ad.u.op->cmd = cmd;
3676 ad.u.op->path = file->f_path;
3677
3678 if (ssid != fsec->sid) {
3679 rc = avc_has_perm(ssid, fsec->sid,
3680 SECCLASS_FD,
3681 FD__USE,
3682 &ad);
3683 if (rc)
3684 goto out;
3685 }
3686
3687 if (unlikely(IS_PRIVATE(inode)))
3688 return 0;
3689
3690 isec = inode_security(inode);
3691 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, requested,
3692 driver, AVC_EXT_IOCTL, xperm, &ad);
3693out:
3694 return rc;
3695}
3696
3697static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3698 unsigned long arg)
3699{
3700 const struct cred *cred = current_cred();
3701 int error = 0;
3702
3703 switch (cmd) {
3704 case FIONREAD:
3705 case FIBMAP:
3706 case FIGETBSZ:
3707 case FS_IOC_GETFLAGS:
3708 case FS_IOC_GETVERSION:
3709 error = file_has_perm(cred, file, FILE__GETATTR);
3710 break;
3711
3712 case FS_IOC_SETFLAGS:
3713 case FS_IOC_SETVERSION:
3714 error = file_has_perm(cred, file, FILE__SETATTR);
3715 break;
3716
3717 /* sys_ioctl() checks */
3718 case FIONBIO:
3719 case FIOASYNC:
3720 error = file_has_perm(cred, file, 0);
3721 break;
3722
3723 case KDSKBENT:
3724 case KDSKBSENT:
3725 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3726 CAP_OPT_NONE, true);
3727 break;
3728
3729 case FIOCLEX:
3730 case FIONCLEX:
3731 if (!selinux_policycap_ioctl_skip_cloexec())
3732 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3733 break;
3734
3735 /* default case assumes that the command will go
3736 * to the file's ioctl() function.
3737 */
3738 default:
3739 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3740 }
3741 return error;
3742}
3743
3744static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd,
3745 unsigned long arg)
3746{
3747 /*
3748 * If we are in a 64-bit kernel running 32-bit userspace, we need to
3749 * make sure we don't compare 32-bit flags to 64-bit flags.
3750 */
3751 switch (cmd) {
3752 case FS_IOC32_GETFLAGS:
3753 cmd = FS_IOC_GETFLAGS;
3754 break;
3755 case FS_IOC32_SETFLAGS:
3756 cmd = FS_IOC_SETFLAGS;
3757 break;
3758 case FS_IOC32_GETVERSION:
3759 cmd = FS_IOC_GETVERSION;
3760 break;
3761 case FS_IOC32_SETVERSION:
3762 cmd = FS_IOC_SETVERSION;
3763 break;
3764 default:
3765 break;
3766 }
3767
3768 return selinux_file_ioctl(file, cmd, arg);
3769}
3770
3771static int default_noexec __ro_after_init;
3772
3773static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3774{
3775 const struct cred *cred = current_cred();
3776 u32 sid = cred_sid(cred);
3777 int rc = 0;
3778
3779 if (default_noexec &&
3780 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3781 (!shared && (prot & PROT_WRITE)))) {
3782 /*
3783 * We are making executable an anonymous mapping or a
3784 * private file mapping that will also be writable.
3785 * This has an additional check.
3786 */
3787 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3788 PROCESS__EXECMEM, NULL);
3789 if (rc)
3790 goto error;
3791 }
3792
3793 if (file) {
3794 /* read access is always possible with a mapping */
3795 u32 av = FILE__READ;
3796
3797 /* write access only matters if the mapping is shared */
3798 if (shared && (prot & PROT_WRITE))
3799 av |= FILE__WRITE;
3800
3801 if (prot & PROT_EXEC)
3802 av |= FILE__EXECUTE;
3803
3804 return file_has_perm(cred, file, av);
3805 }
3806
3807error:
3808 return rc;
3809}
3810
3811static int selinux_mmap_addr(unsigned long addr)
3812{
3813 int rc = 0;
3814
3815 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3816 u32 sid = current_sid();
3817 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3818 MEMPROTECT__MMAP_ZERO, NULL);
3819 }
3820
3821 return rc;
3822}
3823
3824static int selinux_mmap_file(struct file *file,
3825 unsigned long reqprot __always_unused,
3826 unsigned long prot, unsigned long flags)
3827{
3828 struct common_audit_data ad;
3829 int rc;
3830
3831 if (file) {
3832 ad.type = LSM_AUDIT_DATA_FILE;
3833 ad.u.file = file;
3834 rc = inode_has_perm(current_cred(), file_inode(file),
3835 FILE__MAP, &ad);
3836 if (rc)
3837 return rc;
3838 }
3839
3840 return file_map_prot_check(file, prot,
3841 (flags & MAP_TYPE) == MAP_SHARED);
3842}
3843
3844static int selinux_file_mprotect(struct vm_area_struct *vma,
3845 unsigned long reqprot __always_unused,
3846 unsigned long prot)
3847{
3848 const struct cred *cred = current_cred();
3849 u32 sid = cred_sid(cred);
3850
3851 if (default_noexec &&
3852 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3853 int rc = 0;
3854 /*
3855 * We don't use the vma_is_initial_heap() helper as it has
3856 * a history of problems and is currently broken on systems
3857 * where there is no heap, e.g. brk == start_brk. Before
3858 * replacing the conditional below with vma_is_initial_heap(),
3859 * or something similar, please ensure that the logic is the
3860 * same as what we have below or you have tested every possible
3861 * corner case you can think to test.
3862 */
3863 if (vma->vm_start >= vma->vm_mm->start_brk &&
3864 vma->vm_end <= vma->vm_mm->brk) {
3865 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3866 PROCESS__EXECHEAP, NULL);
3867 } else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
3868 vma_is_stack_for_current(vma))) {
3869 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3870 PROCESS__EXECSTACK, NULL);
3871 } else if (vma->vm_file && vma->anon_vma) {
3872 /*
3873 * We are making executable a file mapping that has
3874 * had some COW done. Since pages might have been
3875 * written, check ability to execute the possibly
3876 * modified content. This typically should only
3877 * occur for text relocations.
3878 */
3879 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3880 }
3881 if (rc)
3882 return rc;
3883 }
3884
3885 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3886}
3887
3888static int selinux_file_lock(struct file *file, unsigned int cmd)
3889{
3890 const struct cred *cred = current_cred();
3891
3892 return file_has_perm(cred, file, FILE__LOCK);
3893}
3894
3895static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3896 unsigned long arg)
3897{
3898 const struct cred *cred = current_cred();
3899 int err = 0;
3900
3901 switch (cmd) {
3902 case F_SETFL:
3903 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3904 err = file_has_perm(cred, file, FILE__WRITE);
3905 break;
3906 }
3907 fallthrough;
3908 case F_SETOWN:
3909 case F_SETSIG:
3910 case F_GETFL:
3911 case F_GETOWN:
3912 case F_GETSIG:
3913 case F_GETOWNER_UIDS:
3914 /* Just check FD__USE permission */
3915 err = file_has_perm(cred, file, 0);
3916 break;
3917 case F_GETLK:
3918 case F_SETLK:
3919 case F_SETLKW:
3920 case F_OFD_GETLK:
3921 case F_OFD_SETLK:
3922 case F_OFD_SETLKW:
3923#if BITS_PER_LONG == 32
3924 case F_GETLK64:
3925 case F_SETLK64:
3926 case F_SETLKW64:
3927#endif
3928 err = file_has_perm(cred, file, FILE__LOCK);
3929 break;
3930 }
3931
3932 return err;
3933}
3934
3935static void selinux_file_set_fowner(struct file *file)
3936{
3937 struct file_security_struct *fsec;
3938
3939 fsec = selinux_file(file);
3940 fsec->fown_sid = current_sid();
3941}
3942
3943static int selinux_file_send_sigiotask(struct task_struct *tsk,
3944 struct fown_struct *fown, int signum)
3945{
3946 struct file *file;
3947 u32 sid = task_sid_obj(tsk);
3948 u32 perm;
3949 struct file_security_struct *fsec;
3950
3951 /* struct fown_struct is never outside the context of a struct file */
3952 file = fown->file;
3953
3954 fsec = selinux_file(file);
3955
3956 if (!signum)
3957 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3958 else
3959 perm = signal_to_av(signum);
3960
3961 return avc_has_perm(fsec->fown_sid, sid,
3962 SECCLASS_PROCESS, perm, NULL);
3963}
3964
3965static int selinux_file_receive(struct file *file)
3966{
3967 const struct cred *cred = current_cred();
3968
3969 return file_has_perm(cred, file, file_to_av(file));
3970}
3971
3972static int selinux_file_open(struct file *file)
3973{
3974 struct file_security_struct *fsec;
3975 struct inode_security_struct *isec;
3976
3977 fsec = selinux_file(file);
3978 isec = inode_security(file_inode(file));
3979 /*
3980 * Save inode label and policy sequence number
3981 * at open-time so that selinux_file_permission
3982 * can determine whether revalidation is necessary.
3983 * Task label is already saved in the file security
3984 * struct as its SID.
3985 */
3986 fsec->isid = isec->sid;
3987 fsec->pseqno = avc_policy_seqno();
3988 /*
3989 * Since the inode label or policy seqno may have changed
3990 * between the selinux_inode_permission check and the saving
3991 * of state above, recheck that access is still permitted.
3992 * Otherwise, access might never be revalidated against the
3993 * new inode label or new policy.
3994 * This check is not redundant - do not remove.
3995 */
3996 return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3997}
3998
3999/* task security operations */
4000
4001static int selinux_task_alloc(struct task_struct *task,
4002 unsigned long clone_flags)
4003{
4004 u32 sid = current_sid();
4005
4006 return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
4007}
4008
4009/*
4010 * prepare a new set of credentials for modification
4011 */
4012static int selinux_cred_prepare(struct cred *new, const struct cred *old,
4013 gfp_t gfp)
4014{
4015 const struct task_security_struct *old_tsec = selinux_cred(old);
4016 struct task_security_struct *tsec = selinux_cred(new);
4017
4018 *tsec = *old_tsec;
4019 return 0;
4020}
4021
4022/*
4023 * transfer the SELinux data to a blank set of creds
4024 */
4025static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4026{
4027 const struct task_security_struct *old_tsec = selinux_cred(old);
4028 struct task_security_struct *tsec = selinux_cred(new);
4029
4030 *tsec = *old_tsec;
4031}
4032
4033static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4034{
4035 *secid = cred_sid(c);
4036}
4037
4038static void selinux_cred_getlsmprop(const struct cred *c, struct lsm_prop *prop)
4039{
4040 prop->selinux.secid = cred_sid(c);
4041}
4042
4043/*
4044 * set the security data for a kernel service
4045 * - all the creation contexts are set to unlabelled
4046 */
4047static int selinux_kernel_act_as(struct cred *new, u32 secid)
4048{
4049 struct task_security_struct *tsec = selinux_cred(new);
4050 u32 sid = current_sid();
4051 int ret;
4052
4053 ret = avc_has_perm(sid, secid,
4054 SECCLASS_KERNEL_SERVICE,
4055 KERNEL_SERVICE__USE_AS_OVERRIDE,
4056 NULL);
4057 if (ret == 0) {
4058 tsec->sid = secid;
4059 tsec->create_sid = 0;
4060 tsec->keycreate_sid = 0;
4061 tsec->sockcreate_sid = 0;
4062 }
4063 return ret;
4064}
4065
4066/*
4067 * set the file creation context in a security record to the same as the
4068 * objective context of the specified inode
4069 */
4070static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4071{
4072 struct inode_security_struct *isec = inode_security(inode);
4073 struct task_security_struct *tsec = selinux_cred(new);
4074 u32 sid = current_sid();
4075 int ret;
4076
4077 ret = avc_has_perm(sid, isec->sid,
4078 SECCLASS_KERNEL_SERVICE,
4079 KERNEL_SERVICE__CREATE_FILES_AS,
4080 NULL);
4081
4082 if (ret == 0)
4083 tsec->create_sid = isec->sid;
4084 return ret;
4085}
4086
4087static int selinux_kernel_module_request(char *kmod_name)
4088{
4089 struct common_audit_data ad;
4090
4091 ad.type = LSM_AUDIT_DATA_KMOD;
4092 ad.u.kmod_name = kmod_name;
4093
4094 return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4095 SYSTEM__MODULE_REQUEST, &ad);
4096}
4097
4098static int selinux_kernel_module_from_file(struct file *file)
4099{
4100 struct common_audit_data ad;
4101 struct inode_security_struct *isec;
4102 struct file_security_struct *fsec;
4103 u32 sid = current_sid();
4104 int rc;
4105
4106 /* init_module */
4107 if (file == NULL)
4108 return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
4109 SYSTEM__MODULE_LOAD, NULL);
4110
4111 /* finit_module */
4112
4113 ad.type = LSM_AUDIT_DATA_FILE;
4114 ad.u.file = file;
4115
4116 fsec = selinux_file(file);
4117 if (sid != fsec->sid) {
4118 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4119 if (rc)
4120 return rc;
4121 }
4122
4123 isec = inode_security(file_inode(file));
4124 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
4125 SYSTEM__MODULE_LOAD, &ad);
4126}
4127
4128static int selinux_kernel_read_file(struct file *file,
4129 enum kernel_read_file_id id,
4130 bool contents)
4131{
4132 int rc = 0;
4133
4134 switch (id) {
4135 case READING_MODULE:
4136 rc = selinux_kernel_module_from_file(contents ? file : NULL);
4137 break;
4138 default:
4139 break;
4140 }
4141
4142 return rc;
4143}
4144
4145static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4146{
4147 int rc = 0;
4148
4149 switch (id) {
4150 case LOADING_MODULE:
4151 rc = selinux_kernel_module_from_file(NULL);
4152 break;
4153 default:
4154 break;
4155 }
4156
4157 return rc;
4158}
4159
4160static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4161{
4162 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4163 PROCESS__SETPGID, NULL);
4164}
4165
4166static int selinux_task_getpgid(struct task_struct *p)
4167{
4168 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4169 PROCESS__GETPGID, NULL);
4170}
4171
4172static int selinux_task_getsid(struct task_struct *p)
4173{
4174 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4175 PROCESS__GETSESSION, NULL);
4176}
4177
4178static void selinux_current_getlsmprop_subj(struct lsm_prop *prop)
4179{
4180 prop->selinux.secid = current_sid();
4181}
4182
4183static void selinux_task_getlsmprop_obj(struct task_struct *p,
4184 struct lsm_prop *prop)
4185{
4186 prop->selinux.secid = task_sid_obj(p);
4187}
4188
4189static int selinux_task_setnice(struct task_struct *p, int nice)
4190{
4191 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4192 PROCESS__SETSCHED, NULL);
4193}
4194
4195static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4196{
4197 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4198 PROCESS__SETSCHED, NULL);
4199}
4200
4201static int selinux_task_getioprio(struct task_struct *p)
4202{
4203 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4204 PROCESS__GETSCHED, NULL);
4205}
4206
4207static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4208 unsigned int flags)
4209{
4210 u32 av = 0;
4211
4212 if (!flags)
4213 return 0;
4214 if (flags & LSM_PRLIMIT_WRITE)
4215 av |= PROCESS__SETRLIMIT;
4216 if (flags & LSM_PRLIMIT_READ)
4217 av |= PROCESS__GETRLIMIT;
4218 return avc_has_perm(cred_sid(cred), cred_sid(tcred),
4219 SECCLASS_PROCESS, av, NULL);
4220}
4221
4222static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4223 struct rlimit *new_rlim)
4224{
4225 struct rlimit *old_rlim = p->signal->rlim + resource;
4226
4227 /* Control the ability to change the hard limit (whether
4228 lowering or raising it), so that the hard limit can
4229 later be used as a safe reset point for the soft limit
4230 upon context transitions. See selinux_bprm_committing_creds. */
4231 if (old_rlim->rlim_max != new_rlim->rlim_max)
4232 return avc_has_perm(current_sid(), task_sid_obj(p),
4233 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4234
4235 return 0;
4236}
4237
4238static int selinux_task_setscheduler(struct task_struct *p)
4239{
4240 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4241 PROCESS__SETSCHED, NULL);
4242}
4243
4244static int selinux_task_getscheduler(struct task_struct *p)
4245{
4246 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4247 PROCESS__GETSCHED, NULL);
4248}
4249
4250static int selinux_task_movememory(struct task_struct *p)
4251{
4252 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4253 PROCESS__SETSCHED, NULL);
4254}
4255
4256static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4257 int sig, const struct cred *cred)
4258{
4259 u32 secid;
4260 u32 perm;
4261
4262 if (!sig)
4263 perm = PROCESS__SIGNULL; /* null signal; existence test */
4264 else
4265 perm = signal_to_av(sig);
4266 if (!cred)
4267 secid = current_sid();
4268 else
4269 secid = cred_sid(cred);
4270 return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4271}
4272
4273static void selinux_task_to_inode(struct task_struct *p,
4274 struct inode *inode)
4275{
4276 struct inode_security_struct *isec = selinux_inode(inode);
4277 u32 sid = task_sid_obj(p);
4278
4279 spin_lock(&isec->lock);
4280 isec->sclass = inode_mode_to_security_class(inode->i_mode);
4281 isec->sid = sid;
4282 isec->initialized = LABEL_INITIALIZED;
4283 spin_unlock(&isec->lock);
4284}
4285
4286static int selinux_userns_create(const struct cred *cred)
4287{
4288 u32 sid = current_sid();
4289
4290 return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4291 USER_NAMESPACE__CREATE, NULL);
4292}
4293
4294/* Returns error only if unable to parse addresses */
4295static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4296 struct common_audit_data *ad, u8 *proto)
4297{
4298 int offset, ihlen, ret = -EINVAL;
4299 struct iphdr _iph, *ih;
4300
4301 offset = skb_network_offset(skb);
4302 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4303 if (ih == NULL)
4304 goto out;
4305
4306 ihlen = ih->ihl * 4;
4307 if (ihlen < sizeof(_iph))
4308 goto out;
4309
4310 ad->u.net->v4info.saddr = ih->saddr;
4311 ad->u.net->v4info.daddr = ih->daddr;
4312 ret = 0;
4313
4314 if (proto)
4315 *proto = ih->protocol;
4316
4317 switch (ih->protocol) {
4318 case IPPROTO_TCP: {
4319 struct tcphdr _tcph, *th;
4320
4321 if (ntohs(ih->frag_off) & IP_OFFSET)
4322 break;
4323
4324 offset += ihlen;
4325 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4326 if (th == NULL)
4327 break;
4328
4329 ad->u.net->sport = th->source;
4330 ad->u.net->dport = th->dest;
4331 break;
4332 }
4333
4334 case IPPROTO_UDP: {
4335 struct udphdr _udph, *uh;
4336
4337 if (ntohs(ih->frag_off) & IP_OFFSET)
4338 break;
4339
4340 offset += ihlen;
4341 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4342 if (uh == NULL)
4343 break;
4344
4345 ad->u.net->sport = uh->source;
4346 ad->u.net->dport = uh->dest;
4347 break;
4348 }
4349
4350 case IPPROTO_DCCP: {
4351 struct dccp_hdr _dccph, *dh;
4352
4353 if (ntohs(ih->frag_off) & IP_OFFSET)
4354 break;
4355
4356 offset += ihlen;
4357 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4358 if (dh == NULL)
4359 break;
4360
4361 ad->u.net->sport = dh->dccph_sport;
4362 ad->u.net->dport = dh->dccph_dport;
4363 break;
4364 }
4365
4366#if IS_ENABLED(CONFIG_IP_SCTP)
4367 case IPPROTO_SCTP: {
4368 struct sctphdr _sctph, *sh;
4369
4370 if (ntohs(ih->frag_off) & IP_OFFSET)
4371 break;
4372
4373 offset += ihlen;
4374 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4375 if (sh == NULL)
4376 break;
4377
4378 ad->u.net->sport = sh->source;
4379 ad->u.net->dport = sh->dest;
4380 break;
4381 }
4382#endif
4383 default:
4384 break;
4385 }
4386out:
4387 return ret;
4388}
4389
4390#if IS_ENABLED(CONFIG_IPV6)
4391
4392/* Returns error only if unable to parse addresses */
4393static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4394 struct common_audit_data *ad, u8 *proto)
4395{
4396 u8 nexthdr;
4397 int ret = -EINVAL, offset;
4398 struct ipv6hdr _ipv6h, *ip6;
4399 __be16 frag_off;
4400
4401 offset = skb_network_offset(skb);
4402 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4403 if (ip6 == NULL)
4404 goto out;
4405
4406 ad->u.net->v6info.saddr = ip6->saddr;
4407 ad->u.net->v6info.daddr = ip6->daddr;
4408 ret = 0;
4409
4410 nexthdr = ip6->nexthdr;
4411 offset += sizeof(_ipv6h);
4412 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4413 if (offset < 0)
4414 goto out;
4415
4416 if (proto)
4417 *proto = nexthdr;
4418
4419 switch (nexthdr) {
4420 case IPPROTO_TCP: {
4421 struct tcphdr _tcph, *th;
4422
4423 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4424 if (th == NULL)
4425 break;
4426
4427 ad->u.net->sport = th->source;
4428 ad->u.net->dport = th->dest;
4429 break;
4430 }
4431
4432 case IPPROTO_UDP: {
4433 struct udphdr _udph, *uh;
4434
4435 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4436 if (uh == NULL)
4437 break;
4438
4439 ad->u.net->sport = uh->source;
4440 ad->u.net->dport = uh->dest;
4441 break;
4442 }
4443
4444 case IPPROTO_DCCP: {
4445 struct dccp_hdr _dccph, *dh;
4446
4447 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4448 if (dh == NULL)
4449 break;
4450
4451 ad->u.net->sport = dh->dccph_sport;
4452 ad->u.net->dport = dh->dccph_dport;
4453 break;
4454 }
4455
4456#if IS_ENABLED(CONFIG_IP_SCTP)
4457 case IPPROTO_SCTP: {
4458 struct sctphdr _sctph, *sh;
4459
4460 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4461 if (sh == NULL)
4462 break;
4463
4464 ad->u.net->sport = sh->source;
4465 ad->u.net->dport = sh->dest;
4466 break;
4467 }
4468#endif
4469 /* includes fragments */
4470 default:
4471 break;
4472 }
4473out:
4474 return ret;
4475}
4476
4477#endif /* IPV6 */
4478
4479static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4480 char **_addrp, int src, u8 *proto)
4481{
4482 char *addrp;
4483 int ret;
4484
4485 switch (ad->u.net->family) {
4486 case PF_INET:
4487 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4488 if (ret)
4489 goto parse_error;
4490 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4491 &ad->u.net->v4info.daddr);
4492 goto okay;
4493
4494#if IS_ENABLED(CONFIG_IPV6)
4495 case PF_INET6:
4496 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4497 if (ret)
4498 goto parse_error;
4499 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4500 &ad->u.net->v6info.daddr);
4501 goto okay;
4502#endif /* IPV6 */
4503 default:
4504 addrp = NULL;
4505 goto okay;
4506 }
4507
4508parse_error:
4509 pr_warn(
4510 "SELinux: failure in selinux_parse_skb(),"
4511 " unable to parse packet\n");
4512 return ret;
4513
4514okay:
4515 if (_addrp)
4516 *_addrp = addrp;
4517 return 0;
4518}
4519
4520/**
4521 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4522 * @skb: the packet
4523 * @family: protocol family
4524 * @sid: the packet's peer label SID
4525 *
4526 * Description:
4527 * Check the various different forms of network peer labeling and determine
4528 * the peer label/SID for the packet; most of the magic actually occurs in
4529 * the security server function security_net_peersid_cmp(). The function
4530 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4531 * or -EACCES if @sid is invalid due to inconsistencies with the different
4532 * peer labels.
4533 *
4534 */
4535static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4536{
4537 int err;
4538 u32 xfrm_sid;
4539 u32 nlbl_sid;
4540 u32 nlbl_type;
4541
4542 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4543 if (unlikely(err))
4544 return -EACCES;
4545 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4546 if (unlikely(err))
4547 return -EACCES;
4548
4549 err = security_net_peersid_resolve(nlbl_sid,
4550 nlbl_type, xfrm_sid, sid);
4551 if (unlikely(err)) {
4552 pr_warn(
4553 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4554 " unable to determine packet's peer label\n");
4555 return -EACCES;
4556 }
4557
4558 return 0;
4559}
4560
4561/**
4562 * selinux_conn_sid - Determine the child socket label for a connection
4563 * @sk_sid: the parent socket's SID
4564 * @skb_sid: the packet's SID
4565 * @conn_sid: the resulting connection SID
4566 *
4567 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4568 * combined with the MLS information from @skb_sid in order to create
4569 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy
4570 * of @sk_sid. Returns zero on success, negative values on failure.
4571 *
4572 */
4573static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4574{
4575 int err = 0;
4576
4577 if (skb_sid != SECSID_NULL)
4578 err = security_sid_mls_copy(sk_sid, skb_sid,
4579 conn_sid);
4580 else
4581 *conn_sid = sk_sid;
4582
4583 return err;
4584}
4585
4586/* socket security operations */
4587
4588static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4589 u16 secclass, u32 *socksid)
4590{
4591 if (tsec->sockcreate_sid > SECSID_NULL) {
4592 *socksid = tsec->sockcreate_sid;
4593 return 0;
4594 }
4595
4596 return security_transition_sid(tsec->sid, tsec->sid,
4597 secclass, NULL, socksid);
4598}
4599
4600static bool sock_skip_has_perm(u32 sid)
4601{
4602 if (sid == SECINITSID_KERNEL)
4603 return true;
4604
4605 /*
4606 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
4607 * inherited the kernel context from early boot used to be skipped
4608 * here, so preserve that behavior unless the capability is set.
4609 *
4610 * By setting the capability the policy signals that it is ready
4611 * for this quirk to be fixed. Note that sockets created by a kernel
4612 * thread or a usermode helper executed without a transition will
4613 * still be skipped in this check regardless of the policycap
4614 * setting.
4615 */
4616 if (!selinux_policycap_userspace_initial_context() &&
4617 sid == SECINITSID_INIT)
4618 return true;
4619 return false;
4620}
4621
4622
4623static int sock_has_perm(struct sock *sk, u32 perms)
4624{
4625 struct sk_security_struct *sksec = sk->sk_security;
4626 struct common_audit_data ad;
4627 struct lsm_network_audit net;
4628
4629 if (sock_skip_has_perm(sksec->sid))
4630 return 0;
4631
4632 ad_net_init_from_sk(&ad, &net, sk);
4633
4634 return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
4635 &ad);
4636}
4637
4638static int selinux_socket_create(int family, int type,
4639 int protocol, int kern)
4640{
4641 const struct task_security_struct *tsec = selinux_cred(current_cred());
4642 u32 newsid;
4643 u16 secclass;
4644 int rc;
4645
4646 if (kern)
4647 return 0;
4648
4649 secclass = socket_type_to_security_class(family, type, protocol);
4650 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4651 if (rc)
4652 return rc;
4653
4654 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4655}
4656
4657static int selinux_socket_post_create(struct socket *sock, int family,
4658 int type, int protocol, int kern)
4659{
4660 const struct task_security_struct *tsec = selinux_cred(current_cred());
4661 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4662 struct sk_security_struct *sksec;
4663 u16 sclass = socket_type_to_security_class(family, type, protocol);
4664 u32 sid = SECINITSID_KERNEL;
4665 int err = 0;
4666
4667 if (!kern) {
4668 err = socket_sockcreate_sid(tsec, sclass, &sid);
4669 if (err)
4670 return err;
4671 }
4672
4673 isec->sclass = sclass;
4674 isec->sid = sid;
4675 isec->initialized = LABEL_INITIALIZED;
4676
4677 if (sock->sk) {
4678 sksec = selinux_sock(sock->sk);
4679 sksec->sclass = sclass;
4680 sksec->sid = sid;
4681 /* Allows detection of the first association on this socket */
4682 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4683 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4684
4685 err = selinux_netlbl_socket_post_create(sock->sk, family);
4686 }
4687
4688 return err;
4689}
4690
4691static int selinux_socket_socketpair(struct socket *socka,
4692 struct socket *sockb)
4693{
4694 struct sk_security_struct *sksec_a = selinux_sock(socka->sk);
4695 struct sk_security_struct *sksec_b = selinux_sock(sockb->sk);
4696
4697 sksec_a->peer_sid = sksec_b->sid;
4698 sksec_b->peer_sid = sksec_a->sid;
4699
4700 return 0;
4701}
4702
4703/* Range of port numbers used to automatically bind.
4704 Need to determine whether we should perform a name_bind
4705 permission check between the socket and the port number. */
4706
4707static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4708{
4709 struct sock *sk = sock->sk;
4710 struct sk_security_struct *sksec = selinux_sock(sk);
4711 u16 family;
4712 int err;
4713
4714 err = sock_has_perm(sk, SOCKET__BIND);
4715 if (err)
4716 goto out;
4717
4718 /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4719 family = sk->sk_family;
4720 if (family == PF_INET || family == PF_INET6) {
4721 char *addrp;
4722 struct common_audit_data ad;
4723 struct lsm_network_audit net = {0,};
4724 struct sockaddr_in *addr4 = NULL;
4725 struct sockaddr_in6 *addr6 = NULL;
4726 u16 family_sa;
4727 unsigned short snum;
4728 u32 sid, node_perm;
4729
4730 /*
4731 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4732 * that validates multiple binding addresses. Because of this
4733 * need to check address->sa_family as it is possible to have
4734 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4735 */
4736 if (addrlen < offsetofend(struct sockaddr, sa_family))
4737 return -EINVAL;
4738 family_sa = address->sa_family;
4739 switch (family_sa) {
4740 case AF_UNSPEC:
4741 case AF_INET:
4742 if (addrlen < sizeof(struct sockaddr_in))
4743 return -EINVAL;
4744 addr4 = (struct sockaddr_in *)address;
4745 if (family_sa == AF_UNSPEC) {
4746 if (family == PF_INET6) {
4747 /* Length check from inet6_bind_sk() */
4748 if (addrlen < SIN6_LEN_RFC2133)
4749 return -EINVAL;
4750 /* Family check from __inet6_bind() */
4751 goto err_af;
4752 }
4753 /* see __inet_bind(), we only want to allow
4754 * AF_UNSPEC if the address is INADDR_ANY
4755 */
4756 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4757 goto err_af;
4758 family_sa = AF_INET;
4759 }
4760 snum = ntohs(addr4->sin_port);
4761 addrp = (char *)&addr4->sin_addr.s_addr;
4762 break;
4763 case AF_INET6:
4764 if (addrlen < SIN6_LEN_RFC2133)
4765 return -EINVAL;
4766 addr6 = (struct sockaddr_in6 *)address;
4767 snum = ntohs(addr6->sin6_port);
4768 addrp = (char *)&addr6->sin6_addr.s6_addr;
4769 break;
4770 default:
4771 goto err_af;
4772 }
4773
4774 ad.type = LSM_AUDIT_DATA_NET;
4775 ad.u.net = &net;
4776 ad.u.net->sport = htons(snum);
4777 ad.u.net->family = family_sa;
4778
4779 if (snum) {
4780 int low, high;
4781
4782 inet_get_local_port_range(sock_net(sk), &low, &high);
4783
4784 if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4785 snum < low || snum > high) {
4786 err = sel_netport_sid(sk->sk_protocol,
4787 snum, &sid);
4788 if (err)
4789 goto out;
4790 err = avc_has_perm(sksec->sid, sid,
4791 sksec->sclass,
4792 SOCKET__NAME_BIND, &ad);
4793 if (err)
4794 goto out;
4795 }
4796 }
4797
4798 switch (sksec->sclass) {
4799 case SECCLASS_TCP_SOCKET:
4800 node_perm = TCP_SOCKET__NODE_BIND;
4801 break;
4802
4803 case SECCLASS_UDP_SOCKET:
4804 node_perm = UDP_SOCKET__NODE_BIND;
4805 break;
4806
4807 case SECCLASS_DCCP_SOCKET:
4808 node_perm = DCCP_SOCKET__NODE_BIND;
4809 break;
4810
4811 case SECCLASS_SCTP_SOCKET:
4812 node_perm = SCTP_SOCKET__NODE_BIND;
4813 break;
4814
4815 default:
4816 node_perm = RAWIP_SOCKET__NODE_BIND;
4817 break;
4818 }
4819
4820 err = sel_netnode_sid(addrp, family_sa, &sid);
4821 if (err)
4822 goto out;
4823
4824 if (family_sa == AF_INET)
4825 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4826 else
4827 ad.u.net->v6info.saddr = addr6->sin6_addr;
4828
4829 err = avc_has_perm(sksec->sid, sid,
4830 sksec->sclass, node_perm, &ad);
4831 if (err)
4832 goto out;
4833 }
4834out:
4835 return err;
4836err_af:
4837 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4838 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4839 return -EINVAL;
4840 return -EAFNOSUPPORT;
4841}
4842
4843/* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4844 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4845 */
4846static int selinux_socket_connect_helper(struct socket *sock,
4847 struct sockaddr *address, int addrlen)
4848{
4849 struct sock *sk = sock->sk;
4850 struct sk_security_struct *sksec = selinux_sock(sk);
4851 int err;
4852
4853 err = sock_has_perm(sk, SOCKET__CONNECT);
4854 if (err)
4855 return err;
4856 if (addrlen < offsetofend(struct sockaddr, sa_family))
4857 return -EINVAL;
4858
4859 /* connect(AF_UNSPEC) has special handling, as it is a documented
4860 * way to disconnect the socket
4861 */
4862 if (address->sa_family == AF_UNSPEC)
4863 return 0;
4864
4865 /*
4866 * If a TCP, DCCP or SCTP socket, check name_connect permission
4867 * for the port.
4868 */
4869 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4870 sksec->sclass == SECCLASS_DCCP_SOCKET ||
4871 sksec->sclass == SECCLASS_SCTP_SOCKET) {
4872 struct common_audit_data ad;
4873 struct lsm_network_audit net = {0,};
4874 struct sockaddr_in *addr4 = NULL;
4875 struct sockaddr_in6 *addr6 = NULL;
4876 unsigned short snum;
4877 u32 sid, perm;
4878
4879 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4880 * that validates multiple connect addresses. Because of this
4881 * need to check address->sa_family as it is possible to have
4882 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4883 */
4884 switch (address->sa_family) {
4885 case AF_INET:
4886 addr4 = (struct sockaddr_in *)address;
4887 if (addrlen < sizeof(struct sockaddr_in))
4888 return -EINVAL;
4889 snum = ntohs(addr4->sin_port);
4890 break;
4891 case AF_INET6:
4892 addr6 = (struct sockaddr_in6 *)address;
4893 if (addrlen < SIN6_LEN_RFC2133)
4894 return -EINVAL;
4895 snum = ntohs(addr6->sin6_port);
4896 break;
4897 default:
4898 /* Note that SCTP services expect -EINVAL, whereas
4899 * others expect -EAFNOSUPPORT.
4900 */
4901 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4902 return -EINVAL;
4903 else
4904 return -EAFNOSUPPORT;
4905 }
4906
4907 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4908 if (err)
4909 return err;
4910
4911 switch (sksec->sclass) {
4912 case SECCLASS_TCP_SOCKET:
4913 perm = TCP_SOCKET__NAME_CONNECT;
4914 break;
4915 case SECCLASS_DCCP_SOCKET:
4916 perm = DCCP_SOCKET__NAME_CONNECT;
4917 break;
4918 case SECCLASS_SCTP_SOCKET:
4919 perm = SCTP_SOCKET__NAME_CONNECT;
4920 break;
4921 }
4922
4923 ad.type = LSM_AUDIT_DATA_NET;
4924 ad.u.net = &net;
4925 ad.u.net->dport = htons(snum);
4926 ad.u.net->family = address->sa_family;
4927 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4928 if (err)
4929 return err;
4930 }
4931
4932 return 0;
4933}
4934
4935/* Supports connect(2), see comments in selinux_socket_connect_helper() */
4936static int selinux_socket_connect(struct socket *sock,
4937 struct sockaddr *address, int addrlen)
4938{
4939 int err;
4940 struct sock *sk = sock->sk;
4941
4942 err = selinux_socket_connect_helper(sock, address, addrlen);
4943 if (err)
4944 return err;
4945
4946 return selinux_netlbl_socket_connect(sk, address);
4947}
4948
4949static int selinux_socket_listen(struct socket *sock, int backlog)
4950{
4951 return sock_has_perm(sock->sk, SOCKET__LISTEN);
4952}
4953
4954static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4955{
4956 int err;
4957 struct inode_security_struct *isec;
4958 struct inode_security_struct *newisec;
4959 u16 sclass;
4960 u32 sid;
4961
4962 err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4963 if (err)
4964 return err;
4965
4966 isec = inode_security_novalidate(SOCK_INODE(sock));
4967 spin_lock(&isec->lock);
4968 sclass = isec->sclass;
4969 sid = isec->sid;
4970 spin_unlock(&isec->lock);
4971
4972 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4973 newisec->sclass = sclass;
4974 newisec->sid = sid;
4975 newisec->initialized = LABEL_INITIALIZED;
4976
4977 return 0;
4978}
4979
4980static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4981 int size)
4982{
4983 return sock_has_perm(sock->sk, SOCKET__WRITE);
4984}
4985
4986static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4987 int size, int flags)
4988{
4989 return sock_has_perm(sock->sk, SOCKET__READ);
4990}
4991
4992static int selinux_socket_getsockname(struct socket *sock)
4993{
4994 return sock_has_perm(sock->sk, SOCKET__GETATTR);
4995}
4996
4997static int selinux_socket_getpeername(struct socket *sock)
4998{
4999 return sock_has_perm(sock->sk, SOCKET__GETATTR);
5000}
5001
5002static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
5003{
5004 int err;
5005
5006 err = sock_has_perm(sock->sk, SOCKET__SETOPT);
5007 if (err)
5008 return err;
5009
5010 return selinux_netlbl_socket_setsockopt(sock, level, optname);
5011}
5012
5013static int selinux_socket_getsockopt(struct socket *sock, int level,
5014 int optname)
5015{
5016 return sock_has_perm(sock->sk, SOCKET__GETOPT);
5017}
5018
5019static int selinux_socket_shutdown(struct socket *sock, int how)
5020{
5021 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
5022}
5023
5024static int selinux_socket_unix_stream_connect(struct sock *sock,
5025 struct sock *other,
5026 struct sock *newsk)
5027{
5028 struct sk_security_struct *sksec_sock = selinux_sock(sock);
5029 struct sk_security_struct *sksec_other = selinux_sock(other);
5030 struct sk_security_struct *sksec_new = selinux_sock(newsk);
5031 struct common_audit_data ad;
5032 struct lsm_network_audit net;
5033 int err;
5034
5035 ad_net_init_from_sk(&ad, &net, other);
5036
5037 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
5038 sksec_other->sclass,
5039 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5040 if (err)
5041 return err;
5042
5043 /* server child socket */
5044 sksec_new->peer_sid = sksec_sock->sid;
5045 err = security_sid_mls_copy(sksec_other->sid,
5046 sksec_sock->sid, &sksec_new->sid);
5047 if (err)
5048 return err;
5049
5050 /* connecting socket */
5051 sksec_sock->peer_sid = sksec_new->sid;
5052
5053 return 0;
5054}
5055
5056static int selinux_socket_unix_may_send(struct socket *sock,
5057 struct socket *other)
5058{
5059 struct sk_security_struct *ssec = selinux_sock(sock->sk);
5060 struct sk_security_struct *osec = selinux_sock(other->sk);
5061 struct common_audit_data ad;
5062 struct lsm_network_audit net;
5063
5064 ad_net_init_from_sk(&ad, &net, other->sk);
5065
5066 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5067 &ad);
5068}
5069
5070static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5071 char *addrp, u16 family, u32 peer_sid,
5072 struct common_audit_data *ad)
5073{
5074 int err;
5075 u32 if_sid;
5076 u32 node_sid;
5077
5078 err = sel_netif_sid(ns, ifindex, &if_sid);
5079 if (err)
5080 return err;
5081 err = avc_has_perm(peer_sid, if_sid,
5082 SECCLASS_NETIF, NETIF__INGRESS, ad);
5083 if (err)
5084 return err;
5085
5086 err = sel_netnode_sid(addrp, family, &node_sid);
5087 if (err)
5088 return err;
5089 return avc_has_perm(peer_sid, node_sid,
5090 SECCLASS_NODE, NODE__RECVFROM, ad);
5091}
5092
5093static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5094 u16 family)
5095{
5096 int err = 0;
5097 struct sk_security_struct *sksec = selinux_sock(sk);
5098 u32 sk_sid = sksec->sid;
5099 struct common_audit_data ad;
5100 struct lsm_network_audit net;
5101 char *addrp;
5102
5103 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5104 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5105 if (err)
5106 return err;
5107
5108 if (selinux_secmark_enabled()) {
5109 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5110 PACKET__RECV, &ad);
5111 if (err)
5112 return err;
5113 }
5114
5115 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5116 if (err)
5117 return err;
5118 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5119
5120 return err;
5121}
5122
5123static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5124{
5125 int err, peerlbl_active, secmark_active;
5126 struct sk_security_struct *sksec = selinux_sock(sk);
5127 u16 family = sk->sk_family;
5128 u32 sk_sid = sksec->sid;
5129 struct common_audit_data ad;
5130 struct lsm_network_audit net;
5131 char *addrp;
5132
5133 if (family != PF_INET && family != PF_INET6)
5134 return 0;
5135
5136 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5137 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5138 family = PF_INET;
5139
5140 /* If any sort of compatibility mode is enabled then handoff processing
5141 * to the selinux_sock_rcv_skb_compat() function to deal with the
5142 * special handling. We do this in an attempt to keep this function
5143 * as fast and as clean as possible. */
5144 if (!selinux_policycap_netpeer())
5145 return selinux_sock_rcv_skb_compat(sk, skb, family);
5146
5147 secmark_active = selinux_secmark_enabled();
5148 peerlbl_active = selinux_peerlbl_enabled();
5149 if (!secmark_active && !peerlbl_active)
5150 return 0;
5151
5152 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5153 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5154 if (err)
5155 return err;
5156
5157 if (peerlbl_active) {
5158 u32 peer_sid;
5159
5160 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5161 if (err)
5162 return err;
5163 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5164 addrp, family, peer_sid, &ad);
5165 if (err) {
5166 selinux_netlbl_err(skb, family, err, 0);
5167 return err;
5168 }
5169 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
5170 PEER__RECV, &ad);
5171 if (err) {
5172 selinux_netlbl_err(skb, family, err, 0);
5173 return err;
5174 }
5175 }
5176
5177 if (secmark_active) {
5178 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5179 PACKET__RECV, &ad);
5180 if (err)
5181 return err;
5182 }
5183
5184 return err;
5185}
5186
5187static int selinux_socket_getpeersec_stream(struct socket *sock,
5188 sockptr_t optval, sockptr_t optlen,
5189 unsigned int len)
5190{
5191 int err = 0;
5192 char *scontext = NULL;
5193 u32 scontext_len;
5194 struct sk_security_struct *sksec = selinux_sock(sock->sk);
5195 u32 peer_sid = SECSID_NULL;
5196
5197 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5198 sksec->sclass == SECCLASS_TCP_SOCKET ||
5199 sksec->sclass == SECCLASS_SCTP_SOCKET)
5200 peer_sid = sksec->peer_sid;
5201 if (peer_sid == SECSID_NULL)
5202 return -ENOPROTOOPT;
5203
5204 err = security_sid_to_context(peer_sid, &scontext,
5205 &scontext_len);
5206 if (err)
5207 return err;
5208 if (scontext_len > len) {
5209 err = -ERANGE;
5210 goto out_len;
5211 }
5212
5213 if (copy_to_sockptr(optval, scontext, scontext_len))
5214 err = -EFAULT;
5215out_len:
5216 if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5217 err = -EFAULT;
5218 kfree(scontext);
5219 return err;
5220}
5221
5222static int selinux_socket_getpeersec_dgram(struct socket *sock,
5223 struct sk_buff *skb, u32 *secid)
5224{
5225 u32 peer_secid = SECSID_NULL;
5226 u16 family;
5227
5228 if (skb && skb->protocol == htons(ETH_P_IP))
5229 family = PF_INET;
5230 else if (skb && skb->protocol == htons(ETH_P_IPV6))
5231 family = PF_INET6;
5232 else if (sock)
5233 family = sock->sk->sk_family;
5234 else {
5235 *secid = SECSID_NULL;
5236 return -EINVAL;
5237 }
5238
5239 if (sock && family == PF_UNIX) {
5240 struct inode_security_struct *isec;
5241 isec = inode_security_novalidate(SOCK_INODE(sock));
5242 peer_secid = isec->sid;
5243 } else if (skb)
5244 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5245
5246 *secid = peer_secid;
5247 if (peer_secid == SECSID_NULL)
5248 return -ENOPROTOOPT;
5249 return 0;
5250}
5251
5252static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5253{
5254 struct sk_security_struct *sksec = selinux_sock(sk);
5255
5256 sksec->peer_sid = SECINITSID_UNLABELED;
5257 sksec->sid = SECINITSID_UNLABELED;
5258 sksec->sclass = SECCLASS_SOCKET;
5259 selinux_netlbl_sk_security_reset(sksec);
5260
5261 return 0;
5262}
5263
5264static void selinux_sk_free_security(struct sock *sk)
5265{
5266 struct sk_security_struct *sksec = selinux_sock(sk);
5267
5268 selinux_netlbl_sk_security_free(sksec);
5269}
5270
5271static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5272{
5273 struct sk_security_struct *sksec = selinux_sock(sk);
5274 struct sk_security_struct *newsksec = selinux_sock(newsk);
5275
5276 newsksec->sid = sksec->sid;
5277 newsksec->peer_sid = sksec->peer_sid;
5278 newsksec->sclass = sksec->sclass;
5279
5280 selinux_netlbl_sk_security_reset(newsksec);
5281}
5282
5283static void selinux_sk_getsecid(const struct sock *sk, u32 *secid)
5284{
5285 if (!sk)
5286 *secid = SECINITSID_ANY_SOCKET;
5287 else {
5288 const struct sk_security_struct *sksec = selinux_sock(sk);
5289
5290 *secid = sksec->sid;
5291 }
5292}
5293
5294static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5295{
5296 struct inode_security_struct *isec =
5297 inode_security_novalidate(SOCK_INODE(parent));
5298 struct sk_security_struct *sksec = selinux_sock(sk);
5299
5300 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5301 sk->sk_family == PF_UNIX)
5302 isec->sid = sksec->sid;
5303 sksec->sclass = isec->sclass;
5304}
5305
5306/*
5307 * Determines peer_secid for the asoc and updates socket's peer label
5308 * if it's the first association on the socket.
5309 */
5310static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5311 struct sk_buff *skb)
5312{
5313 struct sock *sk = asoc->base.sk;
5314 u16 family = sk->sk_family;
5315 struct sk_security_struct *sksec = selinux_sock(sk);
5316 struct common_audit_data ad;
5317 struct lsm_network_audit net;
5318 int err;
5319
5320 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5321 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5322 family = PF_INET;
5323
5324 if (selinux_peerlbl_enabled()) {
5325 asoc->peer_secid = SECSID_NULL;
5326
5327 /* This will return peer_sid = SECSID_NULL if there are
5328 * no peer labels, see security_net_peersid_resolve().
5329 */
5330 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5331 if (err)
5332 return err;
5333
5334 if (asoc->peer_secid == SECSID_NULL)
5335 asoc->peer_secid = SECINITSID_UNLABELED;
5336 } else {
5337 asoc->peer_secid = SECINITSID_UNLABELED;
5338 }
5339
5340 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5341 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5342
5343 /* Here as first association on socket. As the peer SID
5344 * was allowed by peer recv (and the netif/node checks),
5345 * then it is approved by policy and used as the primary
5346 * peer SID for getpeercon(3).
5347 */
5348 sksec->peer_sid = asoc->peer_secid;
5349 } else if (sksec->peer_sid != asoc->peer_secid) {
5350 /* Other association peer SIDs are checked to enforce
5351 * consistency among the peer SIDs.
5352 */
5353 ad_net_init_from_sk(&ad, &net, asoc->base.sk);
5354 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5355 sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5356 &ad);
5357 if (err)
5358 return err;
5359 }
5360 return 0;
5361}
5362
5363/* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5364 * happens on an incoming connect(2), sctp_connectx(3) or
5365 * sctp_sendmsg(3) (with no association already present).
5366 */
5367static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5368 struct sk_buff *skb)
5369{
5370 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5371 u32 conn_sid;
5372 int err;
5373
5374 if (!selinux_policycap_extsockclass())
5375 return 0;
5376
5377 err = selinux_sctp_process_new_assoc(asoc, skb);
5378 if (err)
5379 return err;
5380
5381 /* Compute the MLS component for the connection and store
5382 * the information in asoc. This will be used by SCTP TCP type
5383 * sockets and peeled off connections as they cause a new
5384 * socket to be generated. selinux_sctp_sk_clone() will then
5385 * plug this into the new socket.
5386 */
5387 err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5388 if (err)
5389 return err;
5390
5391 asoc->secid = conn_sid;
5392
5393 /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5394 return selinux_netlbl_sctp_assoc_request(asoc, skb);
5395}
5396
5397/* Called when SCTP receives a COOKIE ACK chunk as the final
5398 * response to an association request (initited by us).
5399 */
5400static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5401 struct sk_buff *skb)
5402{
5403 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5404
5405 if (!selinux_policycap_extsockclass())
5406 return 0;
5407
5408 /* Inherit secid from the parent socket - this will be picked up
5409 * by selinux_sctp_sk_clone() if the association gets peeled off
5410 * into a new socket.
5411 */
5412 asoc->secid = sksec->sid;
5413
5414 return selinux_sctp_process_new_assoc(asoc, skb);
5415}
5416
5417/* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5418 * based on their @optname.
5419 */
5420static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5421 struct sockaddr *address,
5422 int addrlen)
5423{
5424 int len, err = 0, walk_size = 0;
5425 void *addr_buf;
5426 struct sockaddr *addr;
5427 struct socket *sock;
5428
5429 if (!selinux_policycap_extsockclass())
5430 return 0;
5431
5432 /* Process one or more addresses that may be IPv4 or IPv6 */
5433 sock = sk->sk_socket;
5434 addr_buf = address;
5435
5436 while (walk_size < addrlen) {
5437 if (walk_size + sizeof(sa_family_t) > addrlen)
5438 return -EINVAL;
5439
5440 addr = addr_buf;
5441 switch (addr->sa_family) {
5442 case AF_UNSPEC:
5443 case AF_INET:
5444 len = sizeof(struct sockaddr_in);
5445 break;
5446 case AF_INET6:
5447 len = sizeof(struct sockaddr_in6);
5448 break;
5449 default:
5450 return -EINVAL;
5451 }
5452
5453 if (walk_size + len > addrlen)
5454 return -EINVAL;
5455
5456 err = -EINVAL;
5457 switch (optname) {
5458 /* Bind checks */
5459 case SCTP_PRIMARY_ADDR:
5460 case SCTP_SET_PEER_PRIMARY_ADDR:
5461 case SCTP_SOCKOPT_BINDX_ADD:
5462 err = selinux_socket_bind(sock, addr, len);
5463 break;
5464 /* Connect checks */
5465 case SCTP_SOCKOPT_CONNECTX:
5466 case SCTP_PARAM_SET_PRIMARY:
5467 case SCTP_PARAM_ADD_IP:
5468 case SCTP_SENDMSG_CONNECT:
5469 err = selinux_socket_connect_helper(sock, addr, len);
5470 if (err)
5471 return err;
5472
5473 /* As selinux_sctp_bind_connect() is called by the
5474 * SCTP protocol layer, the socket is already locked,
5475 * therefore selinux_netlbl_socket_connect_locked()
5476 * is called here. The situations handled are:
5477 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5478 * whenever a new IP address is added or when a new
5479 * primary address is selected.
5480 * Note that an SCTP connect(2) call happens before
5481 * the SCTP protocol layer and is handled via
5482 * selinux_socket_connect().
5483 */
5484 err = selinux_netlbl_socket_connect_locked(sk, addr);
5485 break;
5486 }
5487
5488 if (err)
5489 return err;
5490
5491 addr_buf += len;
5492 walk_size += len;
5493 }
5494
5495 return 0;
5496}
5497
5498/* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5499static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5500 struct sock *newsk)
5501{
5502 struct sk_security_struct *sksec = selinux_sock(sk);
5503 struct sk_security_struct *newsksec = selinux_sock(newsk);
5504
5505 /* If policy does not support SECCLASS_SCTP_SOCKET then call
5506 * the non-sctp clone version.
5507 */
5508 if (!selinux_policycap_extsockclass())
5509 return selinux_sk_clone_security(sk, newsk);
5510
5511 newsksec->sid = asoc->secid;
5512 newsksec->peer_sid = asoc->peer_secid;
5513 newsksec->sclass = sksec->sclass;
5514 selinux_netlbl_sctp_sk_clone(sk, newsk);
5515}
5516
5517static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5518{
5519 struct sk_security_struct *ssksec = selinux_sock(ssk);
5520 struct sk_security_struct *sksec = selinux_sock(sk);
5521
5522 ssksec->sclass = sksec->sclass;
5523 ssksec->sid = sksec->sid;
5524
5525 /* replace the existing subflow label deleting the existing one
5526 * and re-recreating a new label using the updated context
5527 */
5528 selinux_netlbl_sk_security_free(ssksec);
5529 return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5530}
5531
5532static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5533 struct request_sock *req)
5534{
5535 struct sk_security_struct *sksec = selinux_sock(sk);
5536 int err;
5537 u16 family = req->rsk_ops->family;
5538 u32 connsid;
5539 u32 peersid;
5540
5541 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5542 if (err)
5543 return err;
5544 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5545 if (err)
5546 return err;
5547 req->secid = connsid;
5548 req->peer_secid = peersid;
5549
5550 return selinux_netlbl_inet_conn_request(req, family);
5551}
5552
5553static void selinux_inet_csk_clone(struct sock *newsk,
5554 const struct request_sock *req)
5555{
5556 struct sk_security_struct *newsksec = selinux_sock(newsk);
5557
5558 newsksec->sid = req->secid;
5559 newsksec->peer_sid = req->peer_secid;
5560 /* NOTE: Ideally, we should also get the isec->sid for the
5561 new socket in sync, but we don't have the isec available yet.
5562 So we will wait until sock_graft to do it, by which
5563 time it will have been created and available. */
5564
5565 /* We don't need to take any sort of lock here as we are the only
5566 * thread with access to newsksec */
5567 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5568}
5569
5570static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5571{
5572 u16 family = sk->sk_family;
5573 struct sk_security_struct *sksec = selinux_sock(sk);
5574
5575 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5576 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5577 family = PF_INET;
5578
5579 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5580}
5581
5582static int selinux_secmark_relabel_packet(u32 sid)
5583{
5584 return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO,
5585 NULL);
5586}
5587
5588static void selinux_secmark_refcount_inc(void)
5589{
5590 atomic_inc(&selinux_secmark_refcount);
5591}
5592
5593static void selinux_secmark_refcount_dec(void)
5594{
5595 atomic_dec(&selinux_secmark_refcount);
5596}
5597
5598static void selinux_req_classify_flow(const struct request_sock *req,
5599 struct flowi_common *flic)
5600{
5601 flic->flowic_secid = req->secid;
5602}
5603
5604static int selinux_tun_dev_alloc_security(void *security)
5605{
5606 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5607
5608 tunsec->sid = current_sid();
5609 return 0;
5610}
5611
5612static int selinux_tun_dev_create(void)
5613{
5614 u32 sid = current_sid();
5615
5616 /* we aren't taking into account the "sockcreate" SID since the socket
5617 * that is being created here is not a socket in the traditional sense,
5618 * instead it is a private sock, accessible only to the kernel, and
5619 * representing a wide range of network traffic spanning multiple
5620 * connections unlike traditional sockets - check the TUN driver to
5621 * get a better understanding of why this socket is special */
5622
5623 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5624 NULL);
5625}
5626
5627static int selinux_tun_dev_attach_queue(void *security)
5628{
5629 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5630
5631 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5632 TUN_SOCKET__ATTACH_QUEUE, NULL);
5633}
5634
5635static int selinux_tun_dev_attach(struct sock *sk, void *security)
5636{
5637 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5638 struct sk_security_struct *sksec = selinux_sock(sk);
5639
5640 /* we don't currently perform any NetLabel based labeling here and it
5641 * isn't clear that we would want to do so anyway; while we could apply
5642 * labeling without the support of the TUN user the resulting labeled
5643 * traffic from the other end of the connection would almost certainly
5644 * cause confusion to the TUN user that had no idea network labeling
5645 * protocols were being used */
5646
5647 sksec->sid = tunsec->sid;
5648 sksec->sclass = SECCLASS_TUN_SOCKET;
5649
5650 return 0;
5651}
5652
5653static int selinux_tun_dev_open(void *security)
5654{
5655 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5656 u32 sid = current_sid();
5657 int err;
5658
5659 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5660 TUN_SOCKET__RELABELFROM, NULL);
5661 if (err)
5662 return err;
5663 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5664 TUN_SOCKET__RELABELTO, NULL);
5665 if (err)
5666 return err;
5667 tunsec->sid = sid;
5668
5669 return 0;
5670}
5671
5672#ifdef CONFIG_NETFILTER
5673
5674static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5675 const struct nf_hook_state *state)
5676{
5677 int ifindex;
5678 u16 family;
5679 char *addrp;
5680 u32 peer_sid;
5681 struct common_audit_data ad;
5682 struct lsm_network_audit net;
5683 int secmark_active, peerlbl_active;
5684
5685 if (!selinux_policycap_netpeer())
5686 return NF_ACCEPT;
5687
5688 secmark_active = selinux_secmark_enabled();
5689 peerlbl_active = selinux_peerlbl_enabled();
5690 if (!secmark_active && !peerlbl_active)
5691 return NF_ACCEPT;
5692
5693 family = state->pf;
5694 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5695 return NF_DROP;
5696
5697 ifindex = state->in->ifindex;
5698 ad_net_init_from_iif(&ad, &net, ifindex, family);
5699 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5700 return NF_DROP;
5701
5702 if (peerlbl_active) {
5703 int err;
5704
5705 err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5706 addrp, family, peer_sid, &ad);
5707 if (err) {
5708 selinux_netlbl_err(skb, family, err, 1);
5709 return NF_DROP;
5710 }
5711 }
5712
5713 if (secmark_active)
5714 if (avc_has_perm(peer_sid, skb->secmark,
5715 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5716 return NF_DROP;
5717
5718 if (netlbl_enabled())
5719 /* we do this in the FORWARD path and not the POST_ROUTING
5720 * path because we want to make sure we apply the necessary
5721 * labeling before IPsec is applied so we can leverage AH
5722 * protection */
5723 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5724 return NF_DROP;
5725
5726 return NF_ACCEPT;
5727}
5728
5729static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5730 const struct nf_hook_state *state)
5731{
5732 struct sock *sk;
5733 u32 sid;
5734
5735 if (!netlbl_enabled())
5736 return NF_ACCEPT;
5737
5738 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5739 * because we want to make sure we apply the necessary labeling
5740 * before IPsec is applied so we can leverage AH protection */
5741 sk = sk_to_full_sk(skb->sk);
5742 if (sk) {
5743 struct sk_security_struct *sksec;
5744
5745 if (sk_listener(sk))
5746 /* if the socket is the listening state then this
5747 * packet is a SYN-ACK packet which means it needs to
5748 * be labeled based on the connection/request_sock and
5749 * not the parent socket. unfortunately, we can't
5750 * lookup the request_sock yet as it isn't queued on
5751 * the parent socket until after the SYN-ACK is sent.
5752 * the "solution" is to simply pass the packet as-is
5753 * as any IP option based labeling should be copied
5754 * from the initial connection request (in the IP
5755 * layer). it is far from ideal, but until we get a
5756 * security label in the packet itself this is the
5757 * best we can do. */
5758 return NF_ACCEPT;
5759
5760 /* standard practice, label using the parent socket */
5761 sksec = selinux_sock(sk);
5762 sid = sksec->sid;
5763 } else
5764 sid = SECINITSID_KERNEL;
5765 if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5766 return NF_DROP;
5767
5768 return NF_ACCEPT;
5769}
5770
5771
5772static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5773 const struct nf_hook_state *state)
5774{
5775 struct sock *sk;
5776 struct sk_security_struct *sksec;
5777 struct common_audit_data ad;
5778 struct lsm_network_audit net;
5779 u8 proto = 0;
5780
5781 sk = skb_to_full_sk(skb);
5782 if (sk == NULL)
5783 return NF_ACCEPT;
5784 sksec = selinux_sock(sk);
5785
5786 ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf);
5787 if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5788 return NF_DROP;
5789
5790 if (selinux_secmark_enabled())
5791 if (avc_has_perm(sksec->sid, skb->secmark,
5792 SECCLASS_PACKET, PACKET__SEND, &ad))
5793 return NF_DROP_ERR(-ECONNREFUSED);
5794
5795 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5796 return NF_DROP_ERR(-ECONNREFUSED);
5797
5798 return NF_ACCEPT;
5799}
5800
5801static unsigned int selinux_ip_postroute(void *priv,
5802 struct sk_buff *skb,
5803 const struct nf_hook_state *state)
5804{
5805 u16 family;
5806 u32 secmark_perm;
5807 u32 peer_sid;
5808 int ifindex;
5809 struct sock *sk;
5810 struct common_audit_data ad;
5811 struct lsm_network_audit net;
5812 char *addrp;
5813 int secmark_active, peerlbl_active;
5814
5815 /* If any sort of compatibility mode is enabled then handoff processing
5816 * to the selinux_ip_postroute_compat() function to deal with the
5817 * special handling. We do this in an attempt to keep this function
5818 * as fast and as clean as possible. */
5819 if (!selinux_policycap_netpeer())
5820 return selinux_ip_postroute_compat(skb, state);
5821
5822 secmark_active = selinux_secmark_enabled();
5823 peerlbl_active = selinux_peerlbl_enabled();
5824 if (!secmark_active && !peerlbl_active)
5825 return NF_ACCEPT;
5826
5827 sk = skb_to_full_sk(skb);
5828
5829#ifdef CONFIG_XFRM
5830 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5831 * packet transformation so allow the packet to pass without any checks
5832 * since we'll have another chance to perform access control checks
5833 * when the packet is on it's final way out.
5834 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5835 * is NULL, in this case go ahead and apply access control.
5836 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5837 * TCP listening state we cannot wait until the XFRM processing
5838 * is done as we will miss out on the SA label if we do;
5839 * unfortunately, this means more work, but it is only once per
5840 * connection. */
5841 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5842 !(sk && sk_listener(sk)))
5843 return NF_ACCEPT;
5844#endif
5845
5846 family = state->pf;
5847 if (sk == NULL) {
5848 /* Without an associated socket the packet is either coming
5849 * from the kernel or it is being forwarded; check the packet
5850 * to determine which and if the packet is being forwarded
5851 * query the packet directly to determine the security label. */
5852 if (skb->skb_iif) {
5853 secmark_perm = PACKET__FORWARD_OUT;
5854 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5855 return NF_DROP;
5856 } else {
5857 secmark_perm = PACKET__SEND;
5858 peer_sid = SECINITSID_KERNEL;
5859 }
5860 } else if (sk_listener(sk)) {
5861 /* Locally generated packet but the associated socket is in the
5862 * listening state which means this is a SYN-ACK packet. In
5863 * this particular case the correct security label is assigned
5864 * to the connection/request_sock but unfortunately we can't
5865 * query the request_sock as it isn't queued on the parent
5866 * socket until after the SYN-ACK packet is sent; the only
5867 * viable choice is to regenerate the label like we do in
5868 * selinux_inet_conn_request(). See also selinux_ip_output()
5869 * for similar problems. */
5870 u32 skb_sid;
5871 struct sk_security_struct *sksec;
5872
5873 sksec = selinux_sock(sk);
5874 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5875 return NF_DROP;
5876 /* At this point, if the returned skb peerlbl is SECSID_NULL
5877 * and the packet has been through at least one XFRM
5878 * transformation then we must be dealing with the "final"
5879 * form of labeled IPsec packet; since we've already applied
5880 * all of our access controls on this packet we can safely
5881 * pass the packet. */
5882 if (skb_sid == SECSID_NULL) {
5883 switch (family) {
5884 case PF_INET:
5885 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5886 return NF_ACCEPT;
5887 break;
5888 case PF_INET6:
5889 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5890 return NF_ACCEPT;
5891 break;
5892 default:
5893 return NF_DROP_ERR(-ECONNREFUSED);
5894 }
5895 }
5896 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5897 return NF_DROP;
5898 secmark_perm = PACKET__SEND;
5899 } else {
5900 /* Locally generated packet, fetch the security label from the
5901 * associated socket. */
5902 struct sk_security_struct *sksec = selinux_sock(sk);
5903 peer_sid = sksec->sid;
5904 secmark_perm = PACKET__SEND;
5905 }
5906
5907 ifindex = state->out->ifindex;
5908 ad_net_init_from_iif(&ad, &net, ifindex, family);
5909 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5910 return NF_DROP;
5911
5912 if (secmark_active)
5913 if (avc_has_perm(peer_sid, skb->secmark,
5914 SECCLASS_PACKET, secmark_perm, &ad))
5915 return NF_DROP_ERR(-ECONNREFUSED);
5916
5917 if (peerlbl_active) {
5918 u32 if_sid;
5919 u32 node_sid;
5920
5921 if (sel_netif_sid(state->net, ifindex, &if_sid))
5922 return NF_DROP;
5923 if (avc_has_perm(peer_sid, if_sid,
5924 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5925 return NF_DROP_ERR(-ECONNREFUSED);
5926
5927 if (sel_netnode_sid(addrp, family, &node_sid))
5928 return NF_DROP;
5929 if (avc_has_perm(peer_sid, node_sid,
5930 SECCLASS_NODE, NODE__SENDTO, &ad))
5931 return NF_DROP_ERR(-ECONNREFUSED);
5932 }
5933
5934 return NF_ACCEPT;
5935}
5936#endif /* CONFIG_NETFILTER */
5937
5938static int nlmsg_sock_has_extended_perms(struct sock *sk, u32 perms, u16 nlmsg_type)
5939{
5940 struct sk_security_struct *sksec = sk->sk_security;
5941 struct common_audit_data ad;
5942 struct lsm_network_audit net;
5943 u8 driver;
5944 u8 xperm;
5945
5946 if (sock_skip_has_perm(sksec->sid))
5947 return 0;
5948
5949 ad_net_init_from_sk(&ad, &net, sk);
5950
5951 driver = nlmsg_type >> 8;
5952 xperm = nlmsg_type & 0xff;
5953
5954 return avc_has_extended_perms(current_sid(), sksec->sid, sksec->sclass,
5955 perms, driver, AVC_EXT_NLMSG, xperm, &ad);
5956}
5957
5958static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5959{
5960 int rc = 0;
5961 unsigned int msg_len;
5962 unsigned int data_len = skb->len;
5963 unsigned char *data = skb->data;
5964 struct nlmsghdr *nlh;
5965 struct sk_security_struct *sksec = selinux_sock(sk);
5966 u16 sclass = sksec->sclass;
5967 u32 perm;
5968
5969 while (data_len >= nlmsg_total_size(0)) {
5970 nlh = (struct nlmsghdr *)data;
5971
5972 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
5973 * users which means we can't reject skb's with bogus
5974 * length fields; our solution is to follow what
5975 * netlink_rcv_skb() does and simply skip processing at
5976 * messages with length fields that are clearly junk
5977 */
5978 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5979 return 0;
5980
5981 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5982 if (rc == 0) {
5983 if (selinux_policycap_netlink_xperm()) {
5984 rc = nlmsg_sock_has_extended_perms(
5985 sk, perm, nlh->nlmsg_type);
5986 } else {
5987 rc = sock_has_perm(sk, perm);
5988 }
5989 if (rc)
5990 return rc;
5991 } else if (rc == -EINVAL) {
5992 /* -EINVAL is a missing msg/perm mapping */
5993 pr_warn_ratelimited("SELinux: unrecognized netlink"
5994 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5995 " pid=%d comm=%s\n",
5996 sk->sk_protocol, nlh->nlmsg_type,
5997 secclass_map[sclass - 1].name,
5998 task_pid_nr(current), current->comm);
5999 if (enforcing_enabled() &&
6000 !security_get_allow_unknown())
6001 return rc;
6002 rc = 0;
6003 } else if (rc == -ENOENT) {
6004 /* -ENOENT is a missing socket/class mapping, ignore */
6005 rc = 0;
6006 } else {
6007 return rc;
6008 }
6009
6010 /* move to the next message after applying netlink padding */
6011 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
6012 if (msg_len >= data_len)
6013 return 0;
6014 data_len -= msg_len;
6015 data += msg_len;
6016 }
6017
6018 return rc;
6019}
6020
6021static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
6022{
6023 isec->sclass = sclass;
6024 isec->sid = current_sid();
6025}
6026
6027static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
6028 u32 perms)
6029{
6030 struct ipc_security_struct *isec;
6031 struct common_audit_data ad;
6032 u32 sid = current_sid();
6033
6034 isec = selinux_ipc(ipc_perms);
6035
6036 ad.type = LSM_AUDIT_DATA_IPC;
6037 ad.u.ipc_id = ipc_perms->key;
6038
6039 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
6040}
6041
6042static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6043{
6044 struct msg_security_struct *msec;
6045
6046 msec = selinux_msg_msg(msg);
6047 msec->sid = SECINITSID_UNLABELED;
6048
6049 return 0;
6050}
6051
6052/* message queue security operations */
6053static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6054{
6055 struct ipc_security_struct *isec;
6056 struct common_audit_data ad;
6057 u32 sid = current_sid();
6058
6059 isec = selinux_ipc(msq);
6060 ipc_init_security(isec, SECCLASS_MSGQ);
6061
6062 ad.type = LSM_AUDIT_DATA_IPC;
6063 ad.u.ipc_id = msq->key;
6064
6065 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6066 MSGQ__CREATE, &ad);
6067}
6068
6069static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6070{
6071 struct ipc_security_struct *isec;
6072 struct common_audit_data ad;
6073 u32 sid = current_sid();
6074
6075 isec = selinux_ipc(msq);
6076
6077 ad.type = LSM_AUDIT_DATA_IPC;
6078 ad.u.ipc_id = msq->key;
6079
6080 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6081 MSGQ__ASSOCIATE, &ad);
6082}
6083
6084static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6085{
6086 u32 perms;
6087
6088 switch (cmd) {
6089 case IPC_INFO:
6090 case MSG_INFO:
6091 /* No specific object, just general system-wide information. */
6092 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6093 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6094 case IPC_STAT:
6095 case MSG_STAT:
6096 case MSG_STAT_ANY:
6097 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6098 break;
6099 case IPC_SET:
6100 perms = MSGQ__SETATTR;
6101 break;
6102 case IPC_RMID:
6103 perms = MSGQ__DESTROY;
6104 break;
6105 default:
6106 return 0;
6107 }
6108
6109 return ipc_has_perm(msq, perms);
6110}
6111
6112static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6113{
6114 struct ipc_security_struct *isec;
6115 struct msg_security_struct *msec;
6116 struct common_audit_data ad;
6117 u32 sid = current_sid();
6118 int rc;
6119
6120 isec = selinux_ipc(msq);
6121 msec = selinux_msg_msg(msg);
6122
6123 /*
6124 * First time through, need to assign label to the message
6125 */
6126 if (msec->sid == SECINITSID_UNLABELED) {
6127 /*
6128 * Compute new sid based on current process and
6129 * message queue this message will be stored in
6130 */
6131 rc = security_transition_sid(sid, isec->sid,
6132 SECCLASS_MSG, NULL, &msec->sid);
6133 if (rc)
6134 return rc;
6135 }
6136
6137 ad.type = LSM_AUDIT_DATA_IPC;
6138 ad.u.ipc_id = msq->key;
6139
6140 /* Can this process write to the queue? */
6141 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6142 MSGQ__WRITE, &ad);
6143 if (!rc)
6144 /* Can this process send the message */
6145 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
6146 MSG__SEND, &ad);
6147 if (!rc)
6148 /* Can the message be put in the queue? */
6149 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
6150 MSGQ__ENQUEUE, &ad);
6151
6152 return rc;
6153}
6154
6155static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6156 struct task_struct *target,
6157 long type, int mode)
6158{
6159 struct ipc_security_struct *isec;
6160 struct msg_security_struct *msec;
6161 struct common_audit_data ad;
6162 u32 sid = task_sid_obj(target);
6163 int rc;
6164
6165 isec = selinux_ipc(msq);
6166 msec = selinux_msg_msg(msg);
6167
6168 ad.type = LSM_AUDIT_DATA_IPC;
6169 ad.u.ipc_id = msq->key;
6170
6171 rc = avc_has_perm(sid, isec->sid,
6172 SECCLASS_MSGQ, MSGQ__READ, &ad);
6173 if (!rc)
6174 rc = avc_has_perm(sid, msec->sid,
6175 SECCLASS_MSG, MSG__RECEIVE, &ad);
6176 return rc;
6177}
6178
6179/* Shared Memory security operations */
6180static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6181{
6182 struct ipc_security_struct *isec;
6183 struct common_audit_data ad;
6184 u32 sid = current_sid();
6185
6186 isec = selinux_ipc(shp);
6187 ipc_init_security(isec, SECCLASS_SHM);
6188
6189 ad.type = LSM_AUDIT_DATA_IPC;
6190 ad.u.ipc_id = shp->key;
6191
6192 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6193 SHM__CREATE, &ad);
6194}
6195
6196static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6197{
6198 struct ipc_security_struct *isec;
6199 struct common_audit_data ad;
6200 u32 sid = current_sid();
6201
6202 isec = selinux_ipc(shp);
6203
6204 ad.type = LSM_AUDIT_DATA_IPC;
6205 ad.u.ipc_id = shp->key;
6206
6207 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6208 SHM__ASSOCIATE, &ad);
6209}
6210
6211/* Note, at this point, shp is locked down */
6212static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6213{
6214 u32 perms;
6215
6216 switch (cmd) {
6217 case IPC_INFO:
6218 case SHM_INFO:
6219 /* No specific object, just general system-wide information. */
6220 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6221 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6222 case IPC_STAT:
6223 case SHM_STAT:
6224 case SHM_STAT_ANY:
6225 perms = SHM__GETATTR | SHM__ASSOCIATE;
6226 break;
6227 case IPC_SET:
6228 perms = SHM__SETATTR;
6229 break;
6230 case SHM_LOCK:
6231 case SHM_UNLOCK:
6232 perms = SHM__LOCK;
6233 break;
6234 case IPC_RMID:
6235 perms = SHM__DESTROY;
6236 break;
6237 default:
6238 return 0;
6239 }
6240
6241 return ipc_has_perm(shp, perms);
6242}
6243
6244static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6245 char __user *shmaddr, int shmflg)
6246{
6247 u32 perms;
6248
6249 if (shmflg & SHM_RDONLY)
6250 perms = SHM__READ;
6251 else
6252 perms = SHM__READ | SHM__WRITE;
6253
6254 return ipc_has_perm(shp, perms);
6255}
6256
6257/* Semaphore security operations */
6258static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6259{
6260 struct ipc_security_struct *isec;
6261 struct common_audit_data ad;
6262 u32 sid = current_sid();
6263
6264 isec = selinux_ipc(sma);
6265 ipc_init_security(isec, SECCLASS_SEM);
6266
6267 ad.type = LSM_AUDIT_DATA_IPC;
6268 ad.u.ipc_id = sma->key;
6269
6270 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6271 SEM__CREATE, &ad);
6272}
6273
6274static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6275{
6276 struct ipc_security_struct *isec;
6277 struct common_audit_data ad;
6278 u32 sid = current_sid();
6279
6280 isec = selinux_ipc(sma);
6281
6282 ad.type = LSM_AUDIT_DATA_IPC;
6283 ad.u.ipc_id = sma->key;
6284
6285 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6286 SEM__ASSOCIATE, &ad);
6287}
6288
6289/* Note, at this point, sma is locked down */
6290static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6291{
6292 int err;
6293 u32 perms;
6294
6295 switch (cmd) {
6296 case IPC_INFO:
6297 case SEM_INFO:
6298 /* No specific object, just general system-wide information. */
6299 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6300 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6301 case GETPID:
6302 case GETNCNT:
6303 case GETZCNT:
6304 perms = SEM__GETATTR;
6305 break;
6306 case GETVAL:
6307 case GETALL:
6308 perms = SEM__READ;
6309 break;
6310 case SETVAL:
6311 case SETALL:
6312 perms = SEM__WRITE;
6313 break;
6314 case IPC_RMID:
6315 perms = SEM__DESTROY;
6316 break;
6317 case IPC_SET:
6318 perms = SEM__SETATTR;
6319 break;
6320 case IPC_STAT:
6321 case SEM_STAT:
6322 case SEM_STAT_ANY:
6323 perms = SEM__GETATTR | SEM__ASSOCIATE;
6324 break;
6325 default:
6326 return 0;
6327 }
6328
6329 err = ipc_has_perm(sma, perms);
6330 return err;
6331}
6332
6333static int selinux_sem_semop(struct kern_ipc_perm *sma,
6334 struct sembuf *sops, unsigned nsops, int alter)
6335{
6336 u32 perms;
6337
6338 if (alter)
6339 perms = SEM__READ | SEM__WRITE;
6340 else
6341 perms = SEM__READ;
6342
6343 return ipc_has_perm(sma, perms);
6344}
6345
6346static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6347{
6348 u32 av = 0;
6349
6350 av = 0;
6351 if (flag & S_IRUGO)
6352 av |= IPC__UNIX_READ;
6353 if (flag & S_IWUGO)
6354 av |= IPC__UNIX_WRITE;
6355
6356 if (av == 0)
6357 return 0;
6358
6359 return ipc_has_perm(ipcp, av);
6360}
6361
6362static void selinux_ipc_getlsmprop(struct kern_ipc_perm *ipcp,
6363 struct lsm_prop *prop)
6364{
6365 struct ipc_security_struct *isec = selinux_ipc(ipcp);
6366 prop->selinux.secid = isec->sid;
6367}
6368
6369static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6370{
6371 if (inode)
6372 inode_doinit_with_dentry(inode, dentry);
6373}
6374
6375static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
6376 char **value)
6377{
6378 const struct task_security_struct *tsec;
6379 int error;
6380 u32 sid;
6381 u32 len;
6382
6383 rcu_read_lock();
6384 tsec = selinux_cred(__task_cred(p));
6385 if (p != current) {
6386 error = avc_has_perm(current_sid(), tsec->sid,
6387 SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6388 if (error)
6389 goto err_unlock;
6390 }
6391 switch (attr) {
6392 case LSM_ATTR_CURRENT:
6393 sid = tsec->sid;
6394 break;
6395 case LSM_ATTR_PREV:
6396 sid = tsec->osid;
6397 break;
6398 case LSM_ATTR_EXEC:
6399 sid = tsec->exec_sid;
6400 break;
6401 case LSM_ATTR_FSCREATE:
6402 sid = tsec->create_sid;
6403 break;
6404 case LSM_ATTR_KEYCREATE:
6405 sid = tsec->keycreate_sid;
6406 break;
6407 case LSM_ATTR_SOCKCREATE:
6408 sid = tsec->sockcreate_sid;
6409 break;
6410 default:
6411 error = -EOPNOTSUPP;
6412 goto err_unlock;
6413 }
6414 rcu_read_unlock();
6415
6416 if (sid == SECSID_NULL) {
6417 *value = NULL;
6418 return 0;
6419 }
6420
6421 error = security_sid_to_context(sid, value, &len);
6422 if (error)
6423 return error;
6424 return len;
6425
6426err_unlock:
6427 rcu_read_unlock();
6428 return error;
6429}
6430
6431static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
6432{
6433 struct task_security_struct *tsec;
6434 struct cred *new;
6435 u32 mysid = current_sid(), sid = 0, ptsid;
6436 int error;
6437 char *str = value;
6438
6439 /*
6440 * Basic control over ability to set these attributes at all.
6441 */
6442 switch (attr) {
6443 case LSM_ATTR_EXEC:
6444 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6445 PROCESS__SETEXEC, NULL);
6446 break;
6447 case LSM_ATTR_FSCREATE:
6448 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6449 PROCESS__SETFSCREATE, NULL);
6450 break;
6451 case LSM_ATTR_KEYCREATE:
6452 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6453 PROCESS__SETKEYCREATE, NULL);
6454 break;
6455 case LSM_ATTR_SOCKCREATE:
6456 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6457 PROCESS__SETSOCKCREATE, NULL);
6458 break;
6459 case LSM_ATTR_CURRENT:
6460 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6461 PROCESS__SETCURRENT, NULL);
6462 break;
6463 default:
6464 error = -EOPNOTSUPP;
6465 break;
6466 }
6467 if (error)
6468 return error;
6469
6470 /* Obtain a SID for the context, if one was specified. */
6471 if (size && str[0] && str[0] != '\n') {
6472 if (str[size-1] == '\n') {
6473 str[size-1] = 0;
6474 size--;
6475 }
6476 error = security_context_to_sid(value, size,
6477 &sid, GFP_KERNEL);
6478 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
6479 if (!has_cap_mac_admin(true)) {
6480 struct audit_buffer *ab;
6481 size_t audit_size;
6482
6483 /* We strip a nul only if it is at the end,
6484 * otherwise the context contains a nul and
6485 * we should audit that */
6486 if (str[size - 1] == '\0')
6487 audit_size = size - 1;
6488 else
6489 audit_size = size;
6490 ab = audit_log_start(audit_context(),
6491 GFP_ATOMIC,
6492 AUDIT_SELINUX_ERR);
6493 if (!ab)
6494 return error;
6495 audit_log_format(ab, "op=fscreate invalid_context=");
6496 audit_log_n_untrustedstring(ab, value,
6497 audit_size);
6498 audit_log_end(ab);
6499
6500 return error;
6501 }
6502 error = security_context_to_sid_force(value, size,
6503 &sid);
6504 }
6505 if (error)
6506 return error;
6507 }
6508
6509 new = prepare_creds();
6510 if (!new)
6511 return -ENOMEM;
6512
6513 /* Permission checking based on the specified context is
6514 performed during the actual operation (execve,
6515 open/mkdir/...), when we know the full context of the
6516 operation. See selinux_bprm_creds_for_exec for the execve
6517 checks and may_create for the file creation checks. The
6518 operation will then fail if the context is not permitted. */
6519 tsec = selinux_cred(new);
6520 if (attr == LSM_ATTR_EXEC) {
6521 tsec->exec_sid = sid;
6522 } else if (attr == LSM_ATTR_FSCREATE) {
6523 tsec->create_sid = sid;
6524 } else if (attr == LSM_ATTR_KEYCREATE) {
6525 if (sid) {
6526 error = avc_has_perm(mysid, sid,
6527 SECCLASS_KEY, KEY__CREATE, NULL);
6528 if (error)
6529 goto abort_change;
6530 }
6531 tsec->keycreate_sid = sid;
6532 } else if (attr == LSM_ATTR_SOCKCREATE) {
6533 tsec->sockcreate_sid = sid;
6534 } else if (attr == LSM_ATTR_CURRENT) {
6535 error = -EINVAL;
6536 if (sid == 0)
6537 goto abort_change;
6538
6539 if (!current_is_single_threaded()) {
6540 error = security_bounded_transition(tsec->sid, sid);
6541 if (error)
6542 goto abort_change;
6543 }
6544
6545 /* Check permissions for the transition. */
6546 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6547 PROCESS__DYNTRANSITION, NULL);
6548 if (error)
6549 goto abort_change;
6550
6551 /* Check for ptracing, and update the task SID if ok.
6552 Otherwise, leave SID unchanged and fail. */
6553 ptsid = ptrace_parent_sid();
6554 if (ptsid != 0) {
6555 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
6556 PROCESS__PTRACE, NULL);
6557 if (error)
6558 goto abort_change;
6559 }
6560
6561 tsec->sid = sid;
6562 } else {
6563 error = -EINVAL;
6564 goto abort_change;
6565 }
6566
6567 commit_creds(new);
6568 return size;
6569
6570abort_change:
6571 abort_creds(new);
6572 return error;
6573}
6574
6575/**
6576 * selinux_getselfattr - Get SELinux current task attributes
6577 * @attr: the requested attribute
6578 * @ctx: buffer to receive the result
6579 * @size: buffer size (input), buffer size used (output)
6580 * @flags: unused
6581 *
6582 * Fill the passed user space @ctx with the details of the requested
6583 * attribute.
6584 *
6585 * Returns the number of attributes on success, an error code otherwise.
6586 * There will only ever be one attribute.
6587 */
6588static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
6589 u32 *size, u32 flags)
6590{
6591 int rc;
6592 char *val = NULL;
6593 int val_len;
6594
6595 val_len = selinux_lsm_getattr(attr, current, &val);
6596 if (val_len < 0)
6597 return val_len;
6598 rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0);
6599 kfree(val);
6600 return (!rc ? 1 : rc);
6601}
6602
6603static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
6604 u32 size, u32 flags)
6605{
6606 int rc;
6607
6608 rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len);
6609 if (rc > 0)
6610 return 0;
6611 return rc;
6612}
6613
6614static int selinux_getprocattr(struct task_struct *p,
6615 const char *name, char **value)
6616{
6617 unsigned int attr = lsm_name_to_attr(name);
6618 int rc;
6619
6620 if (attr) {
6621 rc = selinux_lsm_getattr(attr, p, value);
6622 if (rc != -EOPNOTSUPP)
6623 return rc;
6624 }
6625
6626 return -EINVAL;
6627}
6628
6629static int selinux_setprocattr(const char *name, void *value, size_t size)
6630{
6631 int attr = lsm_name_to_attr(name);
6632
6633 if (attr)
6634 return selinux_lsm_setattr(attr, value, size);
6635 return -EINVAL;
6636}
6637
6638static int selinux_ismaclabel(const char *name)
6639{
6640 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6641}
6642
6643static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6644{
6645 return security_sid_to_context(secid, secdata, seclen);
6646}
6647
6648static int selinux_lsmprop_to_secctx(struct lsm_prop *prop, char **secdata,
6649 u32 *seclen)
6650{
6651 return selinux_secid_to_secctx(prop->selinux.secid, secdata, seclen);
6652}
6653
6654static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6655{
6656 return security_context_to_sid(secdata, seclen,
6657 secid, GFP_KERNEL);
6658}
6659
6660static void selinux_release_secctx(char *secdata, u32 seclen)
6661{
6662 kfree(secdata);
6663}
6664
6665static void selinux_inode_invalidate_secctx(struct inode *inode)
6666{
6667 struct inode_security_struct *isec = selinux_inode(inode);
6668
6669 spin_lock(&isec->lock);
6670 isec->initialized = LABEL_INVALID;
6671 spin_unlock(&isec->lock);
6672}
6673
6674/*
6675 * called with inode->i_mutex locked
6676 */
6677static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6678{
6679 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6680 ctx, ctxlen, 0);
6681 /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6682 return rc == -EOPNOTSUPP ? 0 : rc;
6683}
6684
6685/*
6686 * called with inode->i_mutex locked
6687 */
6688static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6689{
6690 return __vfs_setxattr_locked(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6691 ctx, ctxlen, 0, NULL);
6692}
6693
6694static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6695{
6696 int len = 0;
6697 len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6698 XATTR_SELINUX_SUFFIX, ctx, true);
6699 if (len < 0)
6700 return len;
6701 *ctxlen = len;
6702 return 0;
6703}
6704#ifdef CONFIG_KEYS
6705
6706static int selinux_key_alloc(struct key *k, const struct cred *cred,
6707 unsigned long flags)
6708{
6709 const struct task_security_struct *tsec;
6710 struct key_security_struct *ksec = selinux_key(k);
6711
6712 tsec = selinux_cred(cred);
6713 if (tsec->keycreate_sid)
6714 ksec->sid = tsec->keycreate_sid;
6715 else
6716 ksec->sid = tsec->sid;
6717
6718 return 0;
6719}
6720
6721static int selinux_key_permission(key_ref_t key_ref,
6722 const struct cred *cred,
6723 enum key_need_perm need_perm)
6724{
6725 struct key *key;
6726 struct key_security_struct *ksec;
6727 u32 perm, sid;
6728
6729 switch (need_perm) {
6730 case KEY_NEED_VIEW:
6731 perm = KEY__VIEW;
6732 break;
6733 case KEY_NEED_READ:
6734 perm = KEY__READ;
6735 break;
6736 case KEY_NEED_WRITE:
6737 perm = KEY__WRITE;
6738 break;
6739 case KEY_NEED_SEARCH:
6740 perm = KEY__SEARCH;
6741 break;
6742 case KEY_NEED_LINK:
6743 perm = KEY__LINK;
6744 break;
6745 case KEY_NEED_SETATTR:
6746 perm = KEY__SETATTR;
6747 break;
6748 case KEY_NEED_UNLINK:
6749 case KEY_SYSADMIN_OVERRIDE:
6750 case KEY_AUTHTOKEN_OVERRIDE:
6751 case KEY_DEFER_PERM_CHECK:
6752 return 0;
6753 default:
6754 WARN_ON(1);
6755 return -EPERM;
6756
6757 }
6758
6759 sid = cred_sid(cred);
6760 key = key_ref_to_ptr(key_ref);
6761 ksec = selinux_key(key);
6762
6763 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6764}
6765
6766static int selinux_key_getsecurity(struct key *key, char **_buffer)
6767{
6768 struct key_security_struct *ksec = selinux_key(key);
6769 char *context = NULL;
6770 unsigned len;
6771 int rc;
6772
6773 rc = security_sid_to_context(ksec->sid,
6774 &context, &len);
6775 if (!rc)
6776 rc = len;
6777 *_buffer = context;
6778 return rc;
6779}
6780
6781#ifdef CONFIG_KEY_NOTIFICATIONS
6782static int selinux_watch_key(struct key *key)
6783{
6784 struct key_security_struct *ksec = selinux_key(key);
6785 u32 sid = current_sid();
6786
6787 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6788}
6789#endif
6790#endif
6791
6792#ifdef CONFIG_SECURITY_INFINIBAND
6793static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6794{
6795 struct common_audit_data ad;
6796 int err;
6797 u32 sid = 0;
6798 struct ib_security_struct *sec = ib_sec;
6799 struct lsm_ibpkey_audit ibpkey;
6800
6801 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6802 if (err)
6803 return err;
6804
6805 ad.type = LSM_AUDIT_DATA_IBPKEY;
6806 ibpkey.subnet_prefix = subnet_prefix;
6807 ibpkey.pkey = pkey_val;
6808 ad.u.ibpkey = &ibpkey;
6809 return avc_has_perm(sec->sid, sid,
6810 SECCLASS_INFINIBAND_PKEY,
6811 INFINIBAND_PKEY__ACCESS, &ad);
6812}
6813
6814static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6815 u8 port_num)
6816{
6817 struct common_audit_data ad;
6818 int err;
6819 u32 sid = 0;
6820 struct ib_security_struct *sec = ib_sec;
6821 struct lsm_ibendport_audit ibendport;
6822
6823 err = security_ib_endport_sid(dev_name, port_num,
6824 &sid);
6825
6826 if (err)
6827 return err;
6828
6829 ad.type = LSM_AUDIT_DATA_IBENDPORT;
6830 ibendport.dev_name = dev_name;
6831 ibendport.port = port_num;
6832 ad.u.ibendport = &ibendport;
6833 return avc_has_perm(sec->sid, sid,
6834 SECCLASS_INFINIBAND_ENDPORT,
6835 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6836}
6837
6838static int selinux_ib_alloc_security(void *ib_sec)
6839{
6840 struct ib_security_struct *sec = selinux_ib(ib_sec);
6841
6842 sec->sid = current_sid();
6843 return 0;
6844}
6845#endif
6846
6847#ifdef CONFIG_BPF_SYSCALL
6848static int selinux_bpf(int cmd, union bpf_attr *attr,
6849 unsigned int size)
6850{
6851 u32 sid = current_sid();
6852 int ret;
6853
6854 switch (cmd) {
6855 case BPF_MAP_CREATE:
6856 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6857 NULL);
6858 break;
6859 case BPF_PROG_LOAD:
6860 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6861 NULL);
6862 break;
6863 default:
6864 ret = 0;
6865 break;
6866 }
6867
6868 return ret;
6869}
6870
6871static u32 bpf_map_fmode_to_av(fmode_t fmode)
6872{
6873 u32 av = 0;
6874
6875 if (fmode & FMODE_READ)
6876 av |= BPF__MAP_READ;
6877 if (fmode & FMODE_WRITE)
6878 av |= BPF__MAP_WRITE;
6879 return av;
6880}
6881
6882/* This function will check the file pass through unix socket or binder to see
6883 * if it is a bpf related object. And apply corresponding checks on the bpf
6884 * object based on the type. The bpf maps and programs, not like other files and
6885 * socket, are using a shared anonymous inode inside the kernel as their inode.
6886 * So checking that inode cannot identify if the process have privilege to
6887 * access the bpf object and that's why we have to add this additional check in
6888 * selinux_file_receive and selinux_binder_transfer_files.
6889 */
6890static int bpf_fd_pass(const struct file *file, u32 sid)
6891{
6892 struct bpf_security_struct *bpfsec;
6893 struct bpf_prog *prog;
6894 struct bpf_map *map;
6895 int ret;
6896
6897 if (file->f_op == &bpf_map_fops) {
6898 map = file->private_data;
6899 bpfsec = map->security;
6900 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6901 bpf_map_fmode_to_av(file->f_mode), NULL);
6902 if (ret)
6903 return ret;
6904 } else if (file->f_op == &bpf_prog_fops) {
6905 prog = file->private_data;
6906 bpfsec = prog->aux->security;
6907 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6908 BPF__PROG_RUN, NULL);
6909 if (ret)
6910 return ret;
6911 }
6912 return 0;
6913}
6914
6915static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6916{
6917 u32 sid = current_sid();
6918 struct bpf_security_struct *bpfsec;
6919
6920 bpfsec = map->security;
6921 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6922 bpf_map_fmode_to_av(fmode), NULL);
6923}
6924
6925static int selinux_bpf_prog(struct bpf_prog *prog)
6926{
6927 u32 sid = current_sid();
6928 struct bpf_security_struct *bpfsec;
6929
6930 bpfsec = prog->aux->security;
6931 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6932 BPF__PROG_RUN, NULL);
6933}
6934
6935static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
6936 struct bpf_token *token)
6937{
6938 struct bpf_security_struct *bpfsec;
6939
6940 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6941 if (!bpfsec)
6942 return -ENOMEM;
6943
6944 bpfsec->sid = current_sid();
6945 map->security = bpfsec;
6946
6947 return 0;
6948}
6949
6950static void selinux_bpf_map_free(struct bpf_map *map)
6951{
6952 struct bpf_security_struct *bpfsec = map->security;
6953
6954 map->security = NULL;
6955 kfree(bpfsec);
6956}
6957
6958static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
6959 struct bpf_token *token)
6960{
6961 struct bpf_security_struct *bpfsec;
6962
6963 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6964 if (!bpfsec)
6965 return -ENOMEM;
6966
6967 bpfsec->sid = current_sid();
6968 prog->aux->security = bpfsec;
6969
6970 return 0;
6971}
6972
6973static void selinux_bpf_prog_free(struct bpf_prog *prog)
6974{
6975 struct bpf_security_struct *bpfsec = prog->aux->security;
6976
6977 prog->aux->security = NULL;
6978 kfree(bpfsec);
6979}
6980
6981static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
6982 const struct path *path)
6983{
6984 struct bpf_security_struct *bpfsec;
6985
6986 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6987 if (!bpfsec)
6988 return -ENOMEM;
6989
6990 bpfsec->sid = current_sid();
6991 token->security = bpfsec;
6992
6993 return 0;
6994}
6995
6996static void selinux_bpf_token_free(struct bpf_token *token)
6997{
6998 struct bpf_security_struct *bpfsec = token->security;
6999
7000 token->security = NULL;
7001 kfree(bpfsec);
7002}
7003#endif
7004
7005struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
7006 .lbs_cred = sizeof(struct task_security_struct),
7007 .lbs_file = sizeof(struct file_security_struct),
7008 .lbs_inode = sizeof(struct inode_security_struct),
7009 .lbs_ipc = sizeof(struct ipc_security_struct),
7010 .lbs_key = sizeof(struct key_security_struct),
7011 .lbs_msg_msg = sizeof(struct msg_security_struct),
7012#ifdef CONFIG_PERF_EVENTS
7013 .lbs_perf_event = sizeof(struct perf_event_security_struct),
7014#endif
7015 .lbs_sock = sizeof(struct sk_security_struct),
7016 .lbs_superblock = sizeof(struct superblock_security_struct),
7017 .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS,
7018 .lbs_tun_dev = sizeof(struct tun_security_struct),
7019 .lbs_ib = sizeof(struct ib_security_struct),
7020};
7021
7022#ifdef CONFIG_PERF_EVENTS
7023static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
7024{
7025 u32 requested, sid = current_sid();
7026
7027 if (type == PERF_SECURITY_OPEN)
7028 requested = PERF_EVENT__OPEN;
7029 else if (type == PERF_SECURITY_CPU)
7030 requested = PERF_EVENT__CPU;
7031 else if (type == PERF_SECURITY_KERNEL)
7032 requested = PERF_EVENT__KERNEL;
7033 else if (type == PERF_SECURITY_TRACEPOINT)
7034 requested = PERF_EVENT__TRACEPOINT;
7035 else
7036 return -EINVAL;
7037
7038 return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
7039 requested, NULL);
7040}
7041
7042static int selinux_perf_event_alloc(struct perf_event *event)
7043{
7044 struct perf_event_security_struct *perfsec;
7045
7046 perfsec = selinux_perf_event(event->security);
7047 perfsec->sid = current_sid();
7048
7049 return 0;
7050}
7051
7052static int selinux_perf_event_read(struct perf_event *event)
7053{
7054 struct perf_event_security_struct *perfsec = event->security;
7055 u32 sid = current_sid();
7056
7057 return avc_has_perm(sid, perfsec->sid,
7058 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7059}
7060
7061static int selinux_perf_event_write(struct perf_event *event)
7062{
7063 struct perf_event_security_struct *perfsec = event->security;
7064 u32 sid = current_sid();
7065
7066 return avc_has_perm(sid, perfsec->sid,
7067 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7068}
7069#endif
7070
7071#ifdef CONFIG_IO_URING
7072/**
7073 * selinux_uring_override_creds - check the requested cred override
7074 * @new: the target creds
7075 *
7076 * Check to see if the current task is allowed to override it's credentials
7077 * to service an io_uring operation.
7078 */
7079static int selinux_uring_override_creds(const struct cred *new)
7080{
7081 return avc_has_perm(current_sid(), cred_sid(new),
7082 SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
7083}
7084
7085/**
7086 * selinux_uring_sqpoll - check if a io_uring polling thread can be created
7087 *
7088 * Check to see if the current task is allowed to create a new io_uring
7089 * kernel polling thread.
7090 */
7091static int selinux_uring_sqpoll(void)
7092{
7093 u32 sid = current_sid();
7094
7095 return avc_has_perm(sid, sid,
7096 SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
7097}
7098
7099/**
7100 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
7101 * @ioucmd: the io_uring command structure
7102 *
7103 * Check to see if the current domain is allowed to execute an
7104 * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
7105 *
7106 */
7107static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
7108{
7109 struct file *file = ioucmd->file;
7110 struct inode *inode = file_inode(file);
7111 struct inode_security_struct *isec = selinux_inode(inode);
7112 struct common_audit_data ad;
7113
7114 ad.type = LSM_AUDIT_DATA_FILE;
7115 ad.u.file = file;
7116
7117 return avc_has_perm(current_sid(), isec->sid,
7118 SECCLASS_IO_URING, IO_URING__CMD, &ad);
7119}
7120#endif /* CONFIG_IO_URING */
7121
7122static const struct lsm_id selinux_lsmid = {
7123 .name = "selinux",
7124 .id = LSM_ID_SELINUX,
7125};
7126
7127/*
7128 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7129 * 1. any hooks that don't belong to (2.) or (3.) below,
7130 * 2. hooks that both access structures allocated by other hooks, and allocate
7131 * structures that can be later accessed by other hooks (mostly "cloning"
7132 * hooks),
7133 * 3. hooks that only allocate structures that can be later accessed by other
7134 * hooks ("allocating" hooks).
7135 *
7136 * Please follow block comment delimiters in the list to keep this order.
7137 */
7138static struct security_hook_list selinux_hooks[] __ro_after_init = {
7139 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7140 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7141 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7142 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7143
7144 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7145 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7146 LSM_HOOK_INIT(capget, selinux_capget),
7147 LSM_HOOK_INIT(capset, selinux_capset),
7148 LSM_HOOK_INIT(capable, selinux_capable),
7149 LSM_HOOK_INIT(quotactl, selinux_quotactl),
7150 LSM_HOOK_INIT(quota_on, selinux_quota_on),
7151 LSM_HOOK_INIT(syslog, selinux_syslog),
7152 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7153
7154 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7155
7156 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7157 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7158 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7159
7160 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7161 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7162 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7163 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7164 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7165 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7166 LSM_HOOK_INIT(sb_mount, selinux_mount),
7167 LSM_HOOK_INIT(sb_umount, selinux_umount),
7168 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7169 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7170
7171 LSM_HOOK_INIT(move_mount, selinux_move_mount),
7172
7173 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7174 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7175
7176 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7177 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7178 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7179 LSM_HOOK_INIT(inode_create, selinux_inode_create),
7180 LSM_HOOK_INIT(inode_link, selinux_inode_link),
7181 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7182 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7183 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7184 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7185 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7186 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7187 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7188 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7189 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7190 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7191 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7192 LSM_HOOK_INIT(inode_xattr_skipcap, selinux_inode_xattr_skipcap),
7193 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7194 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7195 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7196 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7197 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7198 LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7199 LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7200 LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7201 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7202 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7203 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7204 LSM_HOOK_INIT(inode_getlsmprop, selinux_inode_getlsmprop),
7205 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7206 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7207 LSM_HOOK_INIT(path_notify, selinux_path_notify),
7208
7209 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7210
7211 LSM_HOOK_INIT(file_permission, selinux_file_permission),
7212 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7213 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7214 LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat),
7215 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7216 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7217 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7218 LSM_HOOK_INIT(file_lock, selinux_file_lock),
7219 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7220 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7221 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7222 LSM_HOOK_INIT(file_receive, selinux_file_receive),
7223
7224 LSM_HOOK_INIT(file_open, selinux_file_open),
7225
7226 LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7227 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7228 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7229 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7230 LSM_HOOK_INIT(cred_getlsmprop, selinux_cred_getlsmprop),
7231 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7232 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7233 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7234 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7235 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7236 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7237 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7238 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7239 LSM_HOOK_INIT(current_getlsmprop_subj, selinux_current_getlsmprop_subj),
7240 LSM_HOOK_INIT(task_getlsmprop_obj, selinux_task_getlsmprop_obj),
7241 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7242 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7243 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7244 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7245 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7246 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7247 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7248 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7249 LSM_HOOK_INIT(task_kill, selinux_task_kill),
7250 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7251 LSM_HOOK_INIT(userns_create, selinux_userns_create),
7252
7253 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7254 LSM_HOOK_INIT(ipc_getlsmprop, selinux_ipc_getlsmprop),
7255
7256 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7257 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7258 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7259 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7260
7261 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7262 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7263 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7264
7265 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7266 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7267 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7268
7269 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7270
7271 LSM_HOOK_INIT(getselfattr, selinux_getselfattr),
7272 LSM_HOOK_INIT(setselfattr, selinux_setselfattr),
7273 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7274 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7275
7276 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7277 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7278 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7279 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7280 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7281 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7282
7283 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7284 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7285
7286 LSM_HOOK_INIT(socket_create, selinux_socket_create),
7287 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7288 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7289 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7290 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7291 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7292 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7293 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7294 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7295 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7296 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7297 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7298 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7299 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7300 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7301 LSM_HOOK_INIT(socket_getpeersec_stream,
7302 selinux_socket_getpeersec_stream),
7303 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7304 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7305 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7306 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7307 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7308 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7309 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7310 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7311 LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7312 LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow),
7313 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7314 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7315 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7316 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7317 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7318 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7319 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7320 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7321 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7322 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7323 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7324#ifdef CONFIG_SECURITY_INFINIBAND
7325 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7326 LSM_HOOK_INIT(ib_endport_manage_subnet,
7327 selinux_ib_endport_manage_subnet),
7328#endif
7329#ifdef CONFIG_SECURITY_NETWORK_XFRM
7330 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7331 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7332 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7333 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7334 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7335 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7336 selinux_xfrm_state_pol_flow_match),
7337 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7338#endif
7339
7340#ifdef CONFIG_KEYS
7341 LSM_HOOK_INIT(key_permission, selinux_key_permission),
7342 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7343#ifdef CONFIG_KEY_NOTIFICATIONS
7344 LSM_HOOK_INIT(watch_key, selinux_watch_key),
7345#endif
7346#endif
7347
7348#ifdef CONFIG_AUDIT
7349 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7350 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7351 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7352#endif
7353
7354#ifdef CONFIG_BPF_SYSCALL
7355 LSM_HOOK_INIT(bpf, selinux_bpf),
7356 LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7357 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7358 LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free),
7359 LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free),
7360 LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free),
7361#endif
7362
7363#ifdef CONFIG_PERF_EVENTS
7364 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7365 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7366 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7367#endif
7368
7369#ifdef CONFIG_IO_URING
7370 LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7371 LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7372 LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7373#endif
7374
7375 /*
7376 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7377 */
7378 LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount),
7379 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7380 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7381 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7382#ifdef CONFIG_SECURITY_NETWORK_XFRM
7383 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7384#endif
7385
7386 /*
7387 * PUT "ALLOCATING" HOOKS HERE
7388 */
7389 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7390 LSM_HOOK_INIT(msg_queue_alloc_security,
7391 selinux_msg_queue_alloc_security),
7392 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7393 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7394 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7395 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7396 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7397 LSM_HOOK_INIT(lsmprop_to_secctx, selinux_lsmprop_to_secctx),
7398 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7399 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7400 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7401#ifdef CONFIG_SECURITY_INFINIBAND
7402 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7403#endif
7404#ifdef CONFIG_SECURITY_NETWORK_XFRM
7405 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7406 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7407 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7408 selinux_xfrm_state_alloc_acquire),
7409#endif
7410#ifdef CONFIG_KEYS
7411 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7412#endif
7413#ifdef CONFIG_AUDIT
7414 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7415#endif
7416#ifdef CONFIG_BPF_SYSCALL
7417 LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create),
7418 LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load),
7419 LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create),
7420#endif
7421#ifdef CONFIG_PERF_EVENTS
7422 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7423#endif
7424};
7425
7426static __init int selinux_init(void)
7427{
7428 pr_info("SELinux: Initializing.\n");
7429
7430 memset(&selinux_state, 0, sizeof(selinux_state));
7431 enforcing_set(selinux_enforcing_boot);
7432 selinux_avc_init();
7433 mutex_init(&selinux_state.status_lock);
7434 mutex_init(&selinux_state.policy_mutex);
7435
7436 /* Set the security state for the initial task. */
7437 cred_init_security();
7438
7439 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7440 if (!default_noexec)
7441 pr_notice("SELinux: virtual memory is executable by default\n");
7442
7443 avc_init();
7444
7445 avtab_cache_init();
7446
7447 ebitmap_cache_init();
7448
7449 hashtab_cache_init();
7450
7451 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
7452 &selinux_lsmid);
7453
7454 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7455 panic("SELinux: Unable to register AVC netcache callback\n");
7456
7457 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7458 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7459
7460 if (selinux_enforcing_boot)
7461 pr_debug("SELinux: Starting in enforcing mode\n");
7462 else
7463 pr_debug("SELinux: Starting in permissive mode\n");
7464
7465 fs_validate_description("selinux", selinux_fs_parameters);
7466
7467 return 0;
7468}
7469
7470static void delayed_superblock_init(struct super_block *sb, void *unused)
7471{
7472 selinux_set_mnt_opts(sb, NULL, 0, NULL);
7473}
7474
7475void selinux_complete_init(void)
7476{
7477 pr_debug("SELinux: Completing initialization.\n");
7478
7479 /* Set up any superblocks initialized prior to the policy load. */
7480 pr_debug("SELinux: Setting up existing superblocks.\n");
7481 iterate_supers(delayed_superblock_init, NULL);
7482}
7483
7484/* SELinux requires early initialization in order to label
7485 all processes and objects when they are created. */
7486DEFINE_LSM(selinux) = {
7487 .name = "selinux",
7488 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7489 .enabled = &selinux_enabled_boot,
7490 .blobs = &selinux_blob_sizes,
7491 .init = selinux_init,
7492};
7493
7494#if defined(CONFIG_NETFILTER)
7495static const struct nf_hook_ops selinux_nf_ops[] = {
7496 {
7497 .hook = selinux_ip_postroute,
7498 .pf = NFPROTO_IPV4,
7499 .hooknum = NF_INET_POST_ROUTING,
7500 .priority = NF_IP_PRI_SELINUX_LAST,
7501 },
7502 {
7503 .hook = selinux_ip_forward,
7504 .pf = NFPROTO_IPV4,
7505 .hooknum = NF_INET_FORWARD,
7506 .priority = NF_IP_PRI_SELINUX_FIRST,
7507 },
7508 {
7509 .hook = selinux_ip_output,
7510 .pf = NFPROTO_IPV4,
7511 .hooknum = NF_INET_LOCAL_OUT,
7512 .priority = NF_IP_PRI_SELINUX_FIRST,
7513 },
7514#if IS_ENABLED(CONFIG_IPV6)
7515 {
7516 .hook = selinux_ip_postroute,
7517 .pf = NFPROTO_IPV6,
7518 .hooknum = NF_INET_POST_ROUTING,
7519 .priority = NF_IP6_PRI_SELINUX_LAST,
7520 },
7521 {
7522 .hook = selinux_ip_forward,
7523 .pf = NFPROTO_IPV6,
7524 .hooknum = NF_INET_FORWARD,
7525 .priority = NF_IP6_PRI_SELINUX_FIRST,
7526 },
7527 {
7528 .hook = selinux_ip_output,
7529 .pf = NFPROTO_IPV6,
7530 .hooknum = NF_INET_LOCAL_OUT,
7531 .priority = NF_IP6_PRI_SELINUX_FIRST,
7532 },
7533#endif /* IPV6 */
7534};
7535
7536static int __net_init selinux_nf_register(struct net *net)
7537{
7538 return nf_register_net_hooks(net, selinux_nf_ops,
7539 ARRAY_SIZE(selinux_nf_ops));
7540}
7541
7542static void __net_exit selinux_nf_unregister(struct net *net)
7543{
7544 nf_unregister_net_hooks(net, selinux_nf_ops,
7545 ARRAY_SIZE(selinux_nf_ops));
7546}
7547
7548static struct pernet_operations selinux_net_ops = {
7549 .init = selinux_nf_register,
7550 .exit = selinux_nf_unregister,
7551};
7552
7553static int __init selinux_nf_ip_init(void)
7554{
7555 int err;
7556
7557 if (!selinux_enabled_boot)
7558 return 0;
7559
7560 pr_debug("SELinux: Registering netfilter hooks\n");
7561
7562 err = register_pernet_subsys(&selinux_net_ops);
7563 if (err)
7564 panic("SELinux: register_pernet_subsys: error %d\n", err);
7565
7566 return 0;
7567}
7568__initcall(selinux_nf_ip_init);
7569#endif /* CONFIG_NETFILTER */
1/*
2 * NSA Security-Enhanced Linux (SELinux) security module
3 *
4 * This file contains the SELinux hook function implementations.
5 *
6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil>
7 * Chris Vance, <cvance@nai.com>
8 * Wayne Salamon, <wsalamon@nai.com>
9 * James Morris <jmorris@redhat.com>
10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Eric Paris <eparis@redhat.com>
14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15 * <dgoeddel@trustedcs.com>
16 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17 * Paul Moore <paul@paul-moore.com>
18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19 * Yuichi Nakamura <ynakam@hitachisoft.jp>
20 *
21 * This program is free software; you can redistribute it and/or modify
22 * it under the terms of the GNU General Public License version 2,
23 * as published by the Free Software Foundation.
24 */
25
26#include <linux/init.h>
27#include <linux/kd.h>
28#include <linux/kernel.h>
29#include <linux/tracehook.h>
30#include <linux/errno.h>
31#include <linux/sched.h>
32#include <linux/lsm_hooks.h>
33#include <linux/xattr.h>
34#include <linux/capability.h>
35#include <linux/unistd.h>
36#include <linux/mm.h>
37#include <linux/mman.h>
38#include <linux/slab.h>
39#include <linux/pagemap.h>
40#include <linux/proc_fs.h>
41#include <linux/swap.h>
42#include <linux/spinlock.h>
43#include <linux/syscalls.h>
44#include <linux/dcache.h>
45#include <linux/file.h>
46#include <linux/fdtable.h>
47#include <linux/namei.h>
48#include <linux/mount.h>
49#include <linux/netfilter_ipv4.h>
50#include <linux/netfilter_ipv6.h>
51#include <linux/tty.h>
52#include <net/icmp.h>
53#include <net/ip.h> /* for local_port_range[] */
54#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
55#include <net/inet_connection_sock.h>
56#include <net/net_namespace.h>
57#include <net/netlabel.h>
58#include <linux/uaccess.h>
59#include <asm/ioctls.h>
60#include <linux/atomic.h>
61#include <linux/bitops.h>
62#include <linux/interrupt.h>
63#include <linux/netdevice.h> /* for network interface checks */
64#include <net/netlink.h>
65#include <linux/tcp.h>
66#include <linux/udp.h>
67#include <linux/dccp.h>
68#include <linux/quota.h>
69#include <linux/un.h> /* for Unix socket types */
70#include <net/af_unix.h> /* for Unix socket types */
71#include <linux/parser.h>
72#include <linux/nfs_mount.h>
73#include <net/ipv6.h>
74#include <linux/hugetlb.h>
75#include <linux/personality.h>
76#include <linux/audit.h>
77#include <linux/string.h>
78#include <linux/selinux.h>
79#include <linux/mutex.h>
80#include <linux/posix-timers.h>
81#include <linux/syslog.h>
82#include <linux/user_namespace.h>
83#include <linux/export.h>
84#include <linux/msg.h>
85#include <linux/shm.h>
86
87#include "avc.h"
88#include "objsec.h"
89#include "netif.h"
90#include "netnode.h"
91#include "netport.h"
92#include "xfrm.h"
93#include "netlabel.h"
94#include "audit.h"
95#include "avc_ss.h"
96
97/* SECMARK reference count */
98static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
99
100#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
101int selinux_enforcing;
102
103static int __init enforcing_setup(char *str)
104{
105 unsigned long enforcing;
106 if (!kstrtoul(str, 0, &enforcing))
107 selinux_enforcing = enforcing ? 1 : 0;
108 return 1;
109}
110__setup("enforcing=", enforcing_setup);
111#endif
112
113#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
114int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
115
116static int __init selinux_enabled_setup(char *str)
117{
118 unsigned long enabled;
119 if (!kstrtoul(str, 0, &enabled))
120 selinux_enabled = enabled ? 1 : 0;
121 return 1;
122}
123__setup("selinux=", selinux_enabled_setup);
124#else
125int selinux_enabled = 1;
126#endif
127
128static struct kmem_cache *sel_inode_cache;
129static struct kmem_cache *file_security_cache;
130
131/**
132 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
133 *
134 * Description:
135 * This function checks the SECMARK reference counter to see if any SECMARK
136 * targets are currently configured, if the reference counter is greater than
137 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
138 * enabled, false (0) if SECMARK is disabled. If the always_check_network
139 * policy capability is enabled, SECMARK is always considered enabled.
140 *
141 */
142static int selinux_secmark_enabled(void)
143{
144 return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
145}
146
147/**
148 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
149 *
150 * Description:
151 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true
152 * (1) if any are enabled or false (0) if neither are enabled. If the
153 * always_check_network policy capability is enabled, peer labeling
154 * is always considered enabled.
155 *
156 */
157static int selinux_peerlbl_enabled(void)
158{
159 return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
160}
161
162static int selinux_netcache_avc_callback(u32 event)
163{
164 if (event == AVC_CALLBACK_RESET) {
165 sel_netif_flush();
166 sel_netnode_flush();
167 sel_netport_flush();
168 synchronize_net();
169 }
170 return 0;
171}
172
173/*
174 * initialise the security for the init task
175 */
176static void cred_init_security(void)
177{
178 struct cred *cred = (struct cred *) current->real_cred;
179 struct task_security_struct *tsec;
180
181 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
182 if (!tsec)
183 panic("SELinux: Failed to initialize initial task.\n");
184
185 tsec->osid = tsec->sid = SECINITSID_KERNEL;
186 cred->security = tsec;
187}
188
189/*
190 * get the security ID of a set of credentials
191 */
192static inline u32 cred_sid(const struct cred *cred)
193{
194 const struct task_security_struct *tsec;
195
196 tsec = cred->security;
197 return tsec->sid;
198}
199
200/*
201 * get the objective security ID of a task
202 */
203static inline u32 task_sid(const struct task_struct *task)
204{
205 u32 sid;
206
207 rcu_read_lock();
208 sid = cred_sid(__task_cred(task));
209 rcu_read_unlock();
210 return sid;
211}
212
213/*
214 * get the subjective security ID of the current task
215 */
216static inline u32 current_sid(void)
217{
218 const struct task_security_struct *tsec = current_security();
219
220 return tsec->sid;
221}
222
223/* Allocate and free functions for each kind of security blob. */
224
225static int inode_alloc_security(struct inode *inode)
226{
227 struct inode_security_struct *isec;
228 u32 sid = current_sid();
229
230 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
231 if (!isec)
232 return -ENOMEM;
233
234 spin_lock_init(&isec->lock);
235 INIT_LIST_HEAD(&isec->list);
236 isec->inode = inode;
237 isec->sid = SECINITSID_UNLABELED;
238 isec->sclass = SECCLASS_FILE;
239 isec->task_sid = sid;
240 isec->initialized = LABEL_INVALID;
241 inode->i_security = isec;
242
243 return 0;
244}
245
246static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
247
248/*
249 * Try reloading inode security labels that have been marked as invalid. The
250 * @may_sleep parameter indicates when sleeping and thus reloading labels is
251 * allowed; when set to false, returns -ECHILD when the label is
252 * invalid. The @opt_dentry parameter should be set to a dentry of the inode;
253 * when no dentry is available, set it to NULL instead.
254 */
255static int __inode_security_revalidate(struct inode *inode,
256 struct dentry *opt_dentry,
257 bool may_sleep)
258{
259 struct inode_security_struct *isec = inode->i_security;
260
261 might_sleep_if(may_sleep);
262
263 if (ss_initialized && isec->initialized != LABEL_INITIALIZED) {
264 if (!may_sleep)
265 return -ECHILD;
266
267 /*
268 * Try reloading the inode security label. This will fail if
269 * @opt_dentry is NULL and no dentry for this inode can be
270 * found; in that case, continue using the old label.
271 */
272 inode_doinit_with_dentry(inode, opt_dentry);
273 }
274 return 0;
275}
276
277static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
278{
279 return inode->i_security;
280}
281
282static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
283{
284 int error;
285
286 error = __inode_security_revalidate(inode, NULL, !rcu);
287 if (error)
288 return ERR_PTR(error);
289 return inode->i_security;
290}
291
292/*
293 * Get the security label of an inode.
294 */
295static struct inode_security_struct *inode_security(struct inode *inode)
296{
297 __inode_security_revalidate(inode, NULL, true);
298 return inode->i_security;
299}
300
301static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
302{
303 struct inode *inode = d_backing_inode(dentry);
304
305 return inode->i_security;
306}
307
308/*
309 * Get the security label of a dentry's backing inode.
310 */
311static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
312{
313 struct inode *inode = d_backing_inode(dentry);
314
315 __inode_security_revalidate(inode, dentry, true);
316 return inode->i_security;
317}
318
319static void inode_free_rcu(struct rcu_head *head)
320{
321 struct inode_security_struct *isec;
322
323 isec = container_of(head, struct inode_security_struct, rcu);
324 kmem_cache_free(sel_inode_cache, isec);
325}
326
327static void inode_free_security(struct inode *inode)
328{
329 struct inode_security_struct *isec = inode->i_security;
330 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
331
332 /*
333 * As not all inode security structures are in a list, we check for
334 * empty list outside of the lock to make sure that we won't waste
335 * time taking a lock doing nothing.
336 *
337 * The list_del_init() function can be safely called more than once.
338 * It should not be possible for this function to be called with
339 * concurrent list_add(), but for better safety against future changes
340 * in the code, we use list_empty_careful() here.
341 */
342 if (!list_empty_careful(&isec->list)) {
343 spin_lock(&sbsec->isec_lock);
344 list_del_init(&isec->list);
345 spin_unlock(&sbsec->isec_lock);
346 }
347
348 /*
349 * The inode may still be referenced in a path walk and
350 * a call to selinux_inode_permission() can be made
351 * after inode_free_security() is called. Ideally, the VFS
352 * wouldn't do this, but fixing that is a much harder
353 * job. For now, simply free the i_security via RCU, and
354 * leave the current inode->i_security pointer intact.
355 * The inode will be freed after the RCU grace period too.
356 */
357 call_rcu(&isec->rcu, inode_free_rcu);
358}
359
360static int file_alloc_security(struct file *file)
361{
362 struct file_security_struct *fsec;
363 u32 sid = current_sid();
364
365 fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
366 if (!fsec)
367 return -ENOMEM;
368
369 fsec->sid = sid;
370 fsec->fown_sid = sid;
371 file->f_security = fsec;
372
373 return 0;
374}
375
376static void file_free_security(struct file *file)
377{
378 struct file_security_struct *fsec = file->f_security;
379 file->f_security = NULL;
380 kmem_cache_free(file_security_cache, fsec);
381}
382
383static int superblock_alloc_security(struct super_block *sb)
384{
385 struct superblock_security_struct *sbsec;
386
387 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
388 if (!sbsec)
389 return -ENOMEM;
390
391 mutex_init(&sbsec->lock);
392 INIT_LIST_HEAD(&sbsec->isec_head);
393 spin_lock_init(&sbsec->isec_lock);
394 sbsec->sb = sb;
395 sbsec->sid = SECINITSID_UNLABELED;
396 sbsec->def_sid = SECINITSID_FILE;
397 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
398 sb->s_security = sbsec;
399
400 return 0;
401}
402
403static void superblock_free_security(struct super_block *sb)
404{
405 struct superblock_security_struct *sbsec = sb->s_security;
406 sb->s_security = NULL;
407 kfree(sbsec);
408}
409
410/* The file system's label must be initialized prior to use. */
411
412static const char *labeling_behaviors[7] = {
413 "uses xattr",
414 "uses transition SIDs",
415 "uses task SIDs",
416 "uses genfs_contexts",
417 "not configured for labeling",
418 "uses mountpoint labeling",
419 "uses native labeling",
420};
421
422static inline int inode_doinit(struct inode *inode)
423{
424 return inode_doinit_with_dentry(inode, NULL);
425}
426
427enum {
428 Opt_error = -1,
429 Opt_context = 1,
430 Opt_fscontext = 2,
431 Opt_defcontext = 3,
432 Opt_rootcontext = 4,
433 Opt_labelsupport = 5,
434 Opt_nextmntopt = 6,
435};
436
437#define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1)
438
439static const match_table_t tokens = {
440 {Opt_context, CONTEXT_STR "%s"},
441 {Opt_fscontext, FSCONTEXT_STR "%s"},
442 {Opt_defcontext, DEFCONTEXT_STR "%s"},
443 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
444 {Opt_labelsupport, LABELSUPP_STR},
445 {Opt_error, NULL},
446};
447
448#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
449
450static int may_context_mount_sb_relabel(u32 sid,
451 struct superblock_security_struct *sbsec,
452 const struct cred *cred)
453{
454 const struct task_security_struct *tsec = cred->security;
455 int rc;
456
457 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
458 FILESYSTEM__RELABELFROM, NULL);
459 if (rc)
460 return rc;
461
462 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
463 FILESYSTEM__RELABELTO, NULL);
464 return rc;
465}
466
467static int may_context_mount_inode_relabel(u32 sid,
468 struct superblock_security_struct *sbsec,
469 const struct cred *cred)
470{
471 const struct task_security_struct *tsec = cred->security;
472 int rc;
473 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
474 FILESYSTEM__RELABELFROM, NULL);
475 if (rc)
476 return rc;
477
478 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
479 FILESYSTEM__ASSOCIATE, NULL);
480 return rc;
481}
482
483static int selinux_is_sblabel_mnt(struct super_block *sb)
484{
485 struct superblock_security_struct *sbsec = sb->s_security;
486
487 return sbsec->behavior == SECURITY_FS_USE_XATTR ||
488 sbsec->behavior == SECURITY_FS_USE_TRANS ||
489 sbsec->behavior == SECURITY_FS_USE_TASK ||
490 sbsec->behavior == SECURITY_FS_USE_NATIVE ||
491 /* Special handling. Genfs but also in-core setxattr handler */
492 !strcmp(sb->s_type->name, "sysfs") ||
493 !strcmp(sb->s_type->name, "pstore") ||
494 !strcmp(sb->s_type->name, "debugfs") ||
495 !strcmp(sb->s_type->name, "rootfs");
496}
497
498static int sb_finish_set_opts(struct super_block *sb)
499{
500 struct superblock_security_struct *sbsec = sb->s_security;
501 struct dentry *root = sb->s_root;
502 struct inode *root_inode = d_backing_inode(root);
503 int rc = 0;
504
505 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
506 /* Make sure that the xattr handler exists and that no
507 error other than -ENODATA is returned by getxattr on
508 the root directory. -ENODATA is ok, as this may be
509 the first boot of the SELinux kernel before we have
510 assigned xattr values to the filesystem. */
511 if (!(root_inode->i_opflags & IOP_XATTR)) {
512 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
513 "xattr support\n", sb->s_id, sb->s_type->name);
514 rc = -EOPNOTSUPP;
515 goto out;
516 }
517
518 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
519 if (rc < 0 && rc != -ENODATA) {
520 if (rc == -EOPNOTSUPP)
521 printk(KERN_WARNING "SELinux: (dev %s, type "
522 "%s) has no security xattr handler\n",
523 sb->s_id, sb->s_type->name);
524 else
525 printk(KERN_WARNING "SELinux: (dev %s, type "
526 "%s) getxattr errno %d\n", sb->s_id,
527 sb->s_type->name, -rc);
528 goto out;
529 }
530 }
531
532 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
533 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
534 sb->s_id, sb->s_type->name);
535
536 sbsec->flags |= SE_SBINITIALIZED;
537 if (selinux_is_sblabel_mnt(sb))
538 sbsec->flags |= SBLABEL_MNT;
539
540 /* Initialize the root inode. */
541 rc = inode_doinit_with_dentry(root_inode, root);
542
543 /* Initialize any other inodes associated with the superblock, e.g.
544 inodes created prior to initial policy load or inodes created
545 during get_sb by a pseudo filesystem that directly
546 populates itself. */
547 spin_lock(&sbsec->isec_lock);
548next_inode:
549 if (!list_empty(&sbsec->isec_head)) {
550 struct inode_security_struct *isec =
551 list_entry(sbsec->isec_head.next,
552 struct inode_security_struct, list);
553 struct inode *inode = isec->inode;
554 list_del_init(&isec->list);
555 spin_unlock(&sbsec->isec_lock);
556 inode = igrab(inode);
557 if (inode) {
558 if (!IS_PRIVATE(inode))
559 inode_doinit(inode);
560 iput(inode);
561 }
562 spin_lock(&sbsec->isec_lock);
563 goto next_inode;
564 }
565 spin_unlock(&sbsec->isec_lock);
566out:
567 return rc;
568}
569
570/*
571 * This function should allow an FS to ask what it's mount security
572 * options were so it can use those later for submounts, displaying
573 * mount options, or whatever.
574 */
575static int selinux_get_mnt_opts(const struct super_block *sb,
576 struct security_mnt_opts *opts)
577{
578 int rc = 0, i;
579 struct superblock_security_struct *sbsec = sb->s_security;
580 char *context = NULL;
581 u32 len;
582 char tmp;
583
584 security_init_mnt_opts(opts);
585
586 if (!(sbsec->flags & SE_SBINITIALIZED))
587 return -EINVAL;
588
589 if (!ss_initialized)
590 return -EINVAL;
591
592 /* make sure we always check enough bits to cover the mask */
593 BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
594
595 tmp = sbsec->flags & SE_MNTMASK;
596 /* count the number of mount options for this sb */
597 for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
598 if (tmp & 0x01)
599 opts->num_mnt_opts++;
600 tmp >>= 1;
601 }
602 /* Check if the Label support flag is set */
603 if (sbsec->flags & SBLABEL_MNT)
604 opts->num_mnt_opts++;
605
606 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
607 if (!opts->mnt_opts) {
608 rc = -ENOMEM;
609 goto out_free;
610 }
611
612 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
613 if (!opts->mnt_opts_flags) {
614 rc = -ENOMEM;
615 goto out_free;
616 }
617
618 i = 0;
619 if (sbsec->flags & FSCONTEXT_MNT) {
620 rc = security_sid_to_context(sbsec->sid, &context, &len);
621 if (rc)
622 goto out_free;
623 opts->mnt_opts[i] = context;
624 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
625 }
626 if (sbsec->flags & CONTEXT_MNT) {
627 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
628 if (rc)
629 goto out_free;
630 opts->mnt_opts[i] = context;
631 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
632 }
633 if (sbsec->flags & DEFCONTEXT_MNT) {
634 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
635 if (rc)
636 goto out_free;
637 opts->mnt_opts[i] = context;
638 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
639 }
640 if (sbsec->flags & ROOTCONTEXT_MNT) {
641 struct dentry *root = sbsec->sb->s_root;
642 struct inode_security_struct *isec = backing_inode_security(root);
643
644 rc = security_sid_to_context(isec->sid, &context, &len);
645 if (rc)
646 goto out_free;
647 opts->mnt_opts[i] = context;
648 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
649 }
650 if (sbsec->flags & SBLABEL_MNT) {
651 opts->mnt_opts[i] = NULL;
652 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
653 }
654
655 BUG_ON(i != opts->num_mnt_opts);
656
657 return 0;
658
659out_free:
660 security_free_mnt_opts(opts);
661 return rc;
662}
663
664static int bad_option(struct superblock_security_struct *sbsec, char flag,
665 u32 old_sid, u32 new_sid)
666{
667 char mnt_flags = sbsec->flags & SE_MNTMASK;
668
669 /* check if the old mount command had the same options */
670 if (sbsec->flags & SE_SBINITIALIZED)
671 if (!(sbsec->flags & flag) ||
672 (old_sid != new_sid))
673 return 1;
674
675 /* check if we were passed the same options twice,
676 * aka someone passed context=a,context=b
677 */
678 if (!(sbsec->flags & SE_SBINITIALIZED))
679 if (mnt_flags & flag)
680 return 1;
681 return 0;
682}
683
684/*
685 * Allow filesystems with binary mount data to explicitly set mount point
686 * labeling information.
687 */
688static int selinux_set_mnt_opts(struct super_block *sb,
689 struct security_mnt_opts *opts,
690 unsigned long kern_flags,
691 unsigned long *set_kern_flags)
692{
693 const struct cred *cred = current_cred();
694 int rc = 0, i;
695 struct superblock_security_struct *sbsec = sb->s_security;
696 const char *name = sb->s_type->name;
697 struct dentry *root = sbsec->sb->s_root;
698 struct inode_security_struct *root_isec;
699 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
700 u32 defcontext_sid = 0;
701 char **mount_options = opts->mnt_opts;
702 int *flags = opts->mnt_opts_flags;
703 int num_opts = opts->num_mnt_opts;
704
705 mutex_lock(&sbsec->lock);
706
707 if (!ss_initialized) {
708 if (!num_opts) {
709 /* Defer initialization until selinux_complete_init,
710 after the initial policy is loaded and the security
711 server is ready to handle calls. */
712 goto out;
713 }
714 rc = -EINVAL;
715 printk(KERN_WARNING "SELinux: Unable to set superblock options "
716 "before the security server is initialized\n");
717 goto out;
718 }
719 if (kern_flags && !set_kern_flags) {
720 /* Specifying internal flags without providing a place to
721 * place the results is not allowed */
722 rc = -EINVAL;
723 goto out;
724 }
725
726 /*
727 * Binary mount data FS will come through this function twice. Once
728 * from an explicit call and once from the generic calls from the vfs.
729 * Since the generic VFS calls will not contain any security mount data
730 * we need to skip the double mount verification.
731 *
732 * This does open a hole in which we will not notice if the first
733 * mount using this sb set explict options and a second mount using
734 * this sb does not set any security options. (The first options
735 * will be used for both mounts)
736 */
737 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
738 && (num_opts == 0))
739 goto out;
740
741 root_isec = backing_inode_security_novalidate(root);
742
743 /*
744 * parse the mount options, check if they are valid sids.
745 * also check if someone is trying to mount the same sb more
746 * than once with different security options.
747 */
748 for (i = 0; i < num_opts; i++) {
749 u32 sid;
750
751 if (flags[i] == SBLABEL_MNT)
752 continue;
753 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
754 if (rc) {
755 printk(KERN_WARNING "SELinux: security_context_str_to_sid"
756 "(%s) failed for (dev %s, type %s) errno=%d\n",
757 mount_options[i], sb->s_id, name, rc);
758 goto out;
759 }
760 switch (flags[i]) {
761 case FSCONTEXT_MNT:
762 fscontext_sid = sid;
763
764 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
765 fscontext_sid))
766 goto out_double_mount;
767
768 sbsec->flags |= FSCONTEXT_MNT;
769 break;
770 case CONTEXT_MNT:
771 context_sid = sid;
772
773 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
774 context_sid))
775 goto out_double_mount;
776
777 sbsec->flags |= CONTEXT_MNT;
778 break;
779 case ROOTCONTEXT_MNT:
780 rootcontext_sid = sid;
781
782 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
783 rootcontext_sid))
784 goto out_double_mount;
785
786 sbsec->flags |= ROOTCONTEXT_MNT;
787
788 break;
789 case DEFCONTEXT_MNT:
790 defcontext_sid = sid;
791
792 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
793 defcontext_sid))
794 goto out_double_mount;
795
796 sbsec->flags |= DEFCONTEXT_MNT;
797
798 break;
799 default:
800 rc = -EINVAL;
801 goto out;
802 }
803 }
804
805 if (sbsec->flags & SE_SBINITIALIZED) {
806 /* previously mounted with options, but not on this attempt? */
807 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
808 goto out_double_mount;
809 rc = 0;
810 goto out;
811 }
812
813 if (strcmp(sb->s_type->name, "proc") == 0)
814 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
815
816 if (!strcmp(sb->s_type->name, "debugfs") ||
817 !strcmp(sb->s_type->name, "sysfs") ||
818 !strcmp(sb->s_type->name, "pstore"))
819 sbsec->flags |= SE_SBGENFS;
820
821 if (!sbsec->behavior) {
822 /*
823 * Determine the labeling behavior to use for this
824 * filesystem type.
825 */
826 rc = security_fs_use(sb);
827 if (rc) {
828 printk(KERN_WARNING
829 "%s: security_fs_use(%s) returned %d\n",
830 __func__, sb->s_type->name, rc);
831 goto out;
832 }
833 }
834
835 /*
836 * If this is a user namespace mount, no contexts are allowed
837 * on the command line and security labels must be ignored.
838 */
839 if (sb->s_user_ns != &init_user_ns) {
840 if (context_sid || fscontext_sid || rootcontext_sid ||
841 defcontext_sid) {
842 rc = -EACCES;
843 goto out;
844 }
845 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
846 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
847 rc = security_transition_sid(current_sid(), current_sid(),
848 SECCLASS_FILE, NULL,
849 &sbsec->mntpoint_sid);
850 if (rc)
851 goto out;
852 }
853 goto out_set_opts;
854 }
855
856 /* sets the context of the superblock for the fs being mounted. */
857 if (fscontext_sid) {
858 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
859 if (rc)
860 goto out;
861
862 sbsec->sid = fscontext_sid;
863 }
864
865 /*
866 * Switch to using mount point labeling behavior.
867 * sets the label used on all file below the mountpoint, and will set
868 * the superblock context if not already set.
869 */
870 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
871 sbsec->behavior = SECURITY_FS_USE_NATIVE;
872 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
873 }
874
875 if (context_sid) {
876 if (!fscontext_sid) {
877 rc = may_context_mount_sb_relabel(context_sid, sbsec,
878 cred);
879 if (rc)
880 goto out;
881 sbsec->sid = context_sid;
882 } else {
883 rc = may_context_mount_inode_relabel(context_sid, sbsec,
884 cred);
885 if (rc)
886 goto out;
887 }
888 if (!rootcontext_sid)
889 rootcontext_sid = context_sid;
890
891 sbsec->mntpoint_sid = context_sid;
892 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
893 }
894
895 if (rootcontext_sid) {
896 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
897 cred);
898 if (rc)
899 goto out;
900
901 root_isec->sid = rootcontext_sid;
902 root_isec->initialized = LABEL_INITIALIZED;
903 }
904
905 if (defcontext_sid) {
906 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
907 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
908 rc = -EINVAL;
909 printk(KERN_WARNING "SELinux: defcontext option is "
910 "invalid for this filesystem type\n");
911 goto out;
912 }
913
914 if (defcontext_sid != sbsec->def_sid) {
915 rc = may_context_mount_inode_relabel(defcontext_sid,
916 sbsec, cred);
917 if (rc)
918 goto out;
919 }
920
921 sbsec->def_sid = defcontext_sid;
922 }
923
924out_set_opts:
925 rc = sb_finish_set_opts(sb);
926out:
927 mutex_unlock(&sbsec->lock);
928 return rc;
929out_double_mount:
930 rc = -EINVAL;
931 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
932 "security settings for (dev %s, type %s)\n", sb->s_id, name);
933 goto out;
934}
935
936static int selinux_cmp_sb_context(const struct super_block *oldsb,
937 const struct super_block *newsb)
938{
939 struct superblock_security_struct *old = oldsb->s_security;
940 struct superblock_security_struct *new = newsb->s_security;
941 char oldflags = old->flags & SE_MNTMASK;
942 char newflags = new->flags & SE_MNTMASK;
943
944 if (oldflags != newflags)
945 goto mismatch;
946 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
947 goto mismatch;
948 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
949 goto mismatch;
950 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
951 goto mismatch;
952 if (oldflags & ROOTCONTEXT_MNT) {
953 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
954 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
955 if (oldroot->sid != newroot->sid)
956 goto mismatch;
957 }
958 return 0;
959mismatch:
960 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, "
961 "different security settings for (dev %s, "
962 "type %s)\n", newsb->s_id, newsb->s_type->name);
963 return -EBUSY;
964}
965
966static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
967 struct super_block *newsb)
968{
969 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
970 struct superblock_security_struct *newsbsec = newsb->s_security;
971
972 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
973 int set_context = (oldsbsec->flags & CONTEXT_MNT);
974 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
975
976 /*
977 * if the parent was able to be mounted it clearly had no special lsm
978 * mount options. thus we can safely deal with this superblock later
979 */
980 if (!ss_initialized)
981 return 0;
982
983 /* how can we clone if the old one wasn't set up?? */
984 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
985
986 /* if fs is reusing a sb, make sure that the contexts match */
987 if (newsbsec->flags & SE_SBINITIALIZED)
988 return selinux_cmp_sb_context(oldsb, newsb);
989
990 mutex_lock(&newsbsec->lock);
991
992 newsbsec->flags = oldsbsec->flags;
993
994 newsbsec->sid = oldsbsec->sid;
995 newsbsec->def_sid = oldsbsec->def_sid;
996 newsbsec->behavior = oldsbsec->behavior;
997
998 if (set_context) {
999 u32 sid = oldsbsec->mntpoint_sid;
1000
1001 if (!set_fscontext)
1002 newsbsec->sid = sid;
1003 if (!set_rootcontext) {
1004 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1005 newisec->sid = sid;
1006 }
1007 newsbsec->mntpoint_sid = sid;
1008 }
1009 if (set_rootcontext) {
1010 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
1011 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1012
1013 newisec->sid = oldisec->sid;
1014 }
1015
1016 sb_finish_set_opts(newsb);
1017 mutex_unlock(&newsbsec->lock);
1018 return 0;
1019}
1020
1021static int selinux_parse_opts_str(char *options,
1022 struct security_mnt_opts *opts)
1023{
1024 char *p;
1025 char *context = NULL, *defcontext = NULL;
1026 char *fscontext = NULL, *rootcontext = NULL;
1027 int rc, num_mnt_opts = 0;
1028
1029 opts->num_mnt_opts = 0;
1030
1031 /* Standard string-based options. */
1032 while ((p = strsep(&options, "|")) != NULL) {
1033 int token;
1034 substring_t args[MAX_OPT_ARGS];
1035
1036 if (!*p)
1037 continue;
1038
1039 token = match_token(p, tokens, args);
1040
1041 switch (token) {
1042 case Opt_context:
1043 if (context || defcontext) {
1044 rc = -EINVAL;
1045 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1046 goto out_err;
1047 }
1048 context = match_strdup(&args[0]);
1049 if (!context) {
1050 rc = -ENOMEM;
1051 goto out_err;
1052 }
1053 break;
1054
1055 case Opt_fscontext:
1056 if (fscontext) {
1057 rc = -EINVAL;
1058 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1059 goto out_err;
1060 }
1061 fscontext = match_strdup(&args[0]);
1062 if (!fscontext) {
1063 rc = -ENOMEM;
1064 goto out_err;
1065 }
1066 break;
1067
1068 case Opt_rootcontext:
1069 if (rootcontext) {
1070 rc = -EINVAL;
1071 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1072 goto out_err;
1073 }
1074 rootcontext = match_strdup(&args[0]);
1075 if (!rootcontext) {
1076 rc = -ENOMEM;
1077 goto out_err;
1078 }
1079 break;
1080
1081 case Opt_defcontext:
1082 if (context || defcontext) {
1083 rc = -EINVAL;
1084 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1085 goto out_err;
1086 }
1087 defcontext = match_strdup(&args[0]);
1088 if (!defcontext) {
1089 rc = -ENOMEM;
1090 goto out_err;
1091 }
1092 break;
1093 case Opt_labelsupport:
1094 break;
1095 default:
1096 rc = -EINVAL;
1097 printk(KERN_WARNING "SELinux: unknown mount option\n");
1098 goto out_err;
1099
1100 }
1101 }
1102
1103 rc = -ENOMEM;
1104 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL);
1105 if (!opts->mnt_opts)
1106 goto out_err;
1107
1108 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int),
1109 GFP_KERNEL);
1110 if (!opts->mnt_opts_flags) {
1111 kfree(opts->mnt_opts);
1112 goto out_err;
1113 }
1114
1115 if (fscontext) {
1116 opts->mnt_opts[num_mnt_opts] = fscontext;
1117 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1118 }
1119 if (context) {
1120 opts->mnt_opts[num_mnt_opts] = context;
1121 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1122 }
1123 if (rootcontext) {
1124 opts->mnt_opts[num_mnt_opts] = rootcontext;
1125 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1126 }
1127 if (defcontext) {
1128 opts->mnt_opts[num_mnt_opts] = defcontext;
1129 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1130 }
1131
1132 opts->num_mnt_opts = num_mnt_opts;
1133 return 0;
1134
1135out_err:
1136 kfree(context);
1137 kfree(defcontext);
1138 kfree(fscontext);
1139 kfree(rootcontext);
1140 return rc;
1141}
1142/*
1143 * string mount options parsing and call set the sbsec
1144 */
1145static int superblock_doinit(struct super_block *sb, void *data)
1146{
1147 int rc = 0;
1148 char *options = data;
1149 struct security_mnt_opts opts;
1150
1151 security_init_mnt_opts(&opts);
1152
1153 if (!data)
1154 goto out;
1155
1156 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1157
1158 rc = selinux_parse_opts_str(options, &opts);
1159 if (rc)
1160 goto out_err;
1161
1162out:
1163 rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1164
1165out_err:
1166 security_free_mnt_opts(&opts);
1167 return rc;
1168}
1169
1170static void selinux_write_opts(struct seq_file *m,
1171 struct security_mnt_opts *opts)
1172{
1173 int i;
1174 char *prefix;
1175
1176 for (i = 0; i < opts->num_mnt_opts; i++) {
1177 char *has_comma;
1178
1179 if (opts->mnt_opts[i])
1180 has_comma = strchr(opts->mnt_opts[i], ',');
1181 else
1182 has_comma = NULL;
1183
1184 switch (opts->mnt_opts_flags[i]) {
1185 case CONTEXT_MNT:
1186 prefix = CONTEXT_STR;
1187 break;
1188 case FSCONTEXT_MNT:
1189 prefix = FSCONTEXT_STR;
1190 break;
1191 case ROOTCONTEXT_MNT:
1192 prefix = ROOTCONTEXT_STR;
1193 break;
1194 case DEFCONTEXT_MNT:
1195 prefix = DEFCONTEXT_STR;
1196 break;
1197 case SBLABEL_MNT:
1198 seq_putc(m, ',');
1199 seq_puts(m, LABELSUPP_STR);
1200 continue;
1201 default:
1202 BUG();
1203 return;
1204 };
1205 /* we need a comma before each option */
1206 seq_putc(m, ',');
1207 seq_puts(m, prefix);
1208 if (has_comma)
1209 seq_putc(m, '\"');
1210 seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1211 if (has_comma)
1212 seq_putc(m, '\"');
1213 }
1214}
1215
1216static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1217{
1218 struct security_mnt_opts opts;
1219 int rc;
1220
1221 rc = selinux_get_mnt_opts(sb, &opts);
1222 if (rc) {
1223 /* before policy load we may get EINVAL, don't show anything */
1224 if (rc == -EINVAL)
1225 rc = 0;
1226 return rc;
1227 }
1228
1229 selinux_write_opts(m, &opts);
1230
1231 security_free_mnt_opts(&opts);
1232
1233 return rc;
1234}
1235
1236static inline u16 inode_mode_to_security_class(umode_t mode)
1237{
1238 switch (mode & S_IFMT) {
1239 case S_IFSOCK:
1240 return SECCLASS_SOCK_FILE;
1241 case S_IFLNK:
1242 return SECCLASS_LNK_FILE;
1243 case S_IFREG:
1244 return SECCLASS_FILE;
1245 case S_IFBLK:
1246 return SECCLASS_BLK_FILE;
1247 case S_IFDIR:
1248 return SECCLASS_DIR;
1249 case S_IFCHR:
1250 return SECCLASS_CHR_FILE;
1251 case S_IFIFO:
1252 return SECCLASS_FIFO_FILE;
1253
1254 }
1255
1256 return SECCLASS_FILE;
1257}
1258
1259static inline int default_protocol_stream(int protocol)
1260{
1261 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1262}
1263
1264static inline int default_protocol_dgram(int protocol)
1265{
1266 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1267}
1268
1269static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1270{
1271 switch (family) {
1272 case PF_UNIX:
1273 switch (type) {
1274 case SOCK_STREAM:
1275 case SOCK_SEQPACKET:
1276 return SECCLASS_UNIX_STREAM_SOCKET;
1277 case SOCK_DGRAM:
1278 return SECCLASS_UNIX_DGRAM_SOCKET;
1279 }
1280 break;
1281 case PF_INET:
1282 case PF_INET6:
1283 switch (type) {
1284 case SOCK_STREAM:
1285 if (default_protocol_stream(protocol))
1286 return SECCLASS_TCP_SOCKET;
1287 else
1288 return SECCLASS_RAWIP_SOCKET;
1289 case SOCK_DGRAM:
1290 if (default_protocol_dgram(protocol))
1291 return SECCLASS_UDP_SOCKET;
1292 else
1293 return SECCLASS_RAWIP_SOCKET;
1294 case SOCK_DCCP:
1295 return SECCLASS_DCCP_SOCKET;
1296 default:
1297 return SECCLASS_RAWIP_SOCKET;
1298 }
1299 break;
1300 case PF_NETLINK:
1301 switch (protocol) {
1302 case NETLINK_ROUTE:
1303 return SECCLASS_NETLINK_ROUTE_SOCKET;
1304 case NETLINK_SOCK_DIAG:
1305 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1306 case NETLINK_NFLOG:
1307 return SECCLASS_NETLINK_NFLOG_SOCKET;
1308 case NETLINK_XFRM:
1309 return SECCLASS_NETLINK_XFRM_SOCKET;
1310 case NETLINK_SELINUX:
1311 return SECCLASS_NETLINK_SELINUX_SOCKET;
1312 case NETLINK_ISCSI:
1313 return SECCLASS_NETLINK_ISCSI_SOCKET;
1314 case NETLINK_AUDIT:
1315 return SECCLASS_NETLINK_AUDIT_SOCKET;
1316 case NETLINK_FIB_LOOKUP:
1317 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1318 case NETLINK_CONNECTOR:
1319 return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1320 case NETLINK_NETFILTER:
1321 return SECCLASS_NETLINK_NETFILTER_SOCKET;
1322 case NETLINK_DNRTMSG:
1323 return SECCLASS_NETLINK_DNRT_SOCKET;
1324 case NETLINK_KOBJECT_UEVENT:
1325 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1326 case NETLINK_GENERIC:
1327 return SECCLASS_NETLINK_GENERIC_SOCKET;
1328 case NETLINK_SCSITRANSPORT:
1329 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1330 case NETLINK_RDMA:
1331 return SECCLASS_NETLINK_RDMA_SOCKET;
1332 case NETLINK_CRYPTO:
1333 return SECCLASS_NETLINK_CRYPTO_SOCKET;
1334 default:
1335 return SECCLASS_NETLINK_SOCKET;
1336 }
1337 case PF_PACKET:
1338 return SECCLASS_PACKET_SOCKET;
1339 case PF_KEY:
1340 return SECCLASS_KEY_SOCKET;
1341 case PF_APPLETALK:
1342 return SECCLASS_APPLETALK_SOCKET;
1343 }
1344
1345 return SECCLASS_SOCKET;
1346}
1347
1348static int selinux_genfs_get_sid(struct dentry *dentry,
1349 u16 tclass,
1350 u16 flags,
1351 u32 *sid)
1352{
1353 int rc;
1354 struct super_block *sb = dentry->d_sb;
1355 char *buffer, *path;
1356
1357 buffer = (char *)__get_free_page(GFP_KERNEL);
1358 if (!buffer)
1359 return -ENOMEM;
1360
1361 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1362 if (IS_ERR(path))
1363 rc = PTR_ERR(path);
1364 else {
1365 if (flags & SE_SBPROC) {
1366 /* each process gets a /proc/PID/ entry. Strip off the
1367 * PID part to get a valid selinux labeling.
1368 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1369 while (path[1] >= '0' && path[1] <= '9') {
1370 path[1] = '/';
1371 path++;
1372 }
1373 }
1374 rc = security_genfs_sid(sb->s_type->name, path, tclass, sid);
1375 }
1376 free_page((unsigned long)buffer);
1377 return rc;
1378}
1379
1380/* The inode's security attributes must be initialized before first use. */
1381static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1382{
1383 struct superblock_security_struct *sbsec = NULL;
1384 struct inode_security_struct *isec = inode->i_security;
1385 u32 task_sid, sid = 0;
1386 u16 sclass;
1387 struct dentry *dentry;
1388#define INITCONTEXTLEN 255
1389 char *context = NULL;
1390 unsigned len = 0;
1391 int rc = 0;
1392
1393 if (isec->initialized == LABEL_INITIALIZED)
1394 return 0;
1395
1396 spin_lock(&isec->lock);
1397 if (isec->initialized == LABEL_INITIALIZED)
1398 goto out_unlock;
1399
1400 if (isec->sclass == SECCLASS_FILE)
1401 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1402
1403 sbsec = inode->i_sb->s_security;
1404 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1405 /* Defer initialization until selinux_complete_init,
1406 after the initial policy is loaded and the security
1407 server is ready to handle calls. */
1408 spin_lock(&sbsec->isec_lock);
1409 if (list_empty(&isec->list))
1410 list_add(&isec->list, &sbsec->isec_head);
1411 spin_unlock(&sbsec->isec_lock);
1412 goto out_unlock;
1413 }
1414
1415 sclass = isec->sclass;
1416 task_sid = isec->task_sid;
1417 sid = isec->sid;
1418 isec->initialized = LABEL_PENDING;
1419 spin_unlock(&isec->lock);
1420
1421 switch (sbsec->behavior) {
1422 case SECURITY_FS_USE_NATIVE:
1423 break;
1424 case SECURITY_FS_USE_XATTR:
1425 if (!(inode->i_opflags & IOP_XATTR)) {
1426 sid = sbsec->def_sid;
1427 break;
1428 }
1429 /* Need a dentry, since the xattr API requires one.
1430 Life would be simpler if we could just pass the inode. */
1431 if (opt_dentry) {
1432 /* Called from d_instantiate or d_splice_alias. */
1433 dentry = dget(opt_dentry);
1434 } else {
1435 /* Called from selinux_complete_init, try to find a dentry. */
1436 dentry = d_find_alias(inode);
1437 }
1438 if (!dentry) {
1439 /*
1440 * this is can be hit on boot when a file is accessed
1441 * before the policy is loaded. When we load policy we
1442 * may find inodes that have no dentry on the
1443 * sbsec->isec_head list. No reason to complain as these
1444 * will get fixed up the next time we go through
1445 * inode_doinit with a dentry, before these inodes could
1446 * be used again by userspace.
1447 */
1448 goto out;
1449 }
1450
1451 len = INITCONTEXTLEN;
1452 context = kmalloc(len+1, GFP_NOFS);
1453 if (!context) {
1454 rc = -ENOMEM;
1455 dput(dentry);
1456 goto out;
1457 }
1458 context[len] = '\0';
1459 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1460 if (rc == -ERANGE) {
1461 kfree(context);
1462
1463 /* Need a larger buffer. Query for the right size. */
1464 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1465 if (rc < 0) {
1466 dput(dentry);
1467 goto out;
1468 }
1469 len = rc;
1470 context = kmalloc(len+1, GFP_NOFS);
1471 if (!context) {
1472 rc = -ENOMEM;
1473 dput(dentry);
1474 goto out;
1475 }
1476 context[len] = '\0';
1477 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1478 }
1479 dput(dentry);
1480 if (rc < 0) {
1481 if (rc != -ENODATA) {
1482 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1483 "%d for dev=%s ino=%ld\n", __func__,
1484 -rc, inode->i_sb->s_id, inode->i_ino);
1485 kfree(context);
1486 goto out;
1487 }
1488 /* Map ENODATA to the default file SID */
1489 sid = sbsec->def_sid;
1490 rc = 0;
1491 } else {
1492 rc = security_context_to_sid_default(context, rc, &sid,
1493 sbsec->def_sid,
1494 GFP_NOFS);
1495 if (rc) {
1496 char *dev = inode->i_sb->s_id;
1497 unsigned long ino = inode->i_ino;
1498
1499 if (rc == -EINVAL) {
1500 if (printk_ratelimit())
1501 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1502 "context=%s. This indicates you may need to relabel the inode or the "
1503 "filesystem in question.\n", ino, dev, context);
1504 } else {
1505 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1506 "returned %d for dev=%s ino=%ld\n",
1507 __func__, context, -rc, dev, ino);
1508 }
1509 kfree(context);
1510 /* Leave with the unlabeled SID */
1511 rc = 0;
1512 break;
1513 }
1514 }
1515 kfree(context);
1516 break;
1517 case SECURITY_FS_USE_TASK:
1518 sid = task_sid;
1519 break;
1520 case SECURITY_FS_USE_TRANS:
1521 /* Default to the fs SID. */
1522 sid = sbsec->sid;
1523
1524 /* Try to obtain a transition SID. */
1525 rc = security_transition_sid(task_sid, sid, sclass, NULL, &sid);
1526 if (rc)
1527 goto out;
1528 break;
1529 case SECURITY_FS_USE_MNTPOINT:
1530 sid = sbsec->mntpoint_sid;
1531 break;
1532 default:
1533 /* Default to the fs superblock SID. */
1534 sid = sbsec->sid;
1535
1536 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1537 /* We must have a dentry to determine the label on
1538 * procfs inodes */
1539 if (opt_dentry)
1540 /* Called from d_instantiate or
1541 * d_splice_alias. */
1542 dentry = dget(opt_dentry);
1543 else
1544 /* Called from selinux_complete_init, try to
1545 * find a dentry. */
1546 dentry = d_find_alias(inode);
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 dput(dentry);
1561 if (rc)
1562 goto out;
1563 }
1564 break;
1565 }
1566
1567out:
1568 spin_lock(&isec->lock);
1569 if (isec->initialized == LABEL_PENDING) {
1570 if (!sid || rc) {
1571 isec->initialized = LABEL_INVALID;
1572 goto out_unlock;
1573 }
1574
1575 isec->initialized = LABEL_INITIALIZED;
1576 isec->sid = sid;
1577 }
1578
1579out_unlock:
1580 spin_unlock(&isec->lock);
1581 return rc;
1582}
1583
1584/* Convert a Linux signal to an access vector. */
1585static inline u32 signal_to_av(int sig)
1586{
1587 u32 perm = 0;
1588
1589 switch (sig) {
1590 case SIGCHLD:
1591 /* Commonly granted from child to parent. */
1592 perm = PROCESS__SIGCHLD;
1593 break;
1594 case SIGKILL:
1595 /* Cannot be caught or ignored */
1596 perm = PROCESS__SIGKILL;
1597 break;
1598 case SIGSTOP:
1599 /* Cannot be caught or ignored */
1600 perm = PROCESS__SIGSTOP;
1601 break;
1602 default:
1603 /* All other signals. */
1604 perm = PROCESS__SIGNAL;
1605 break;
1606 }
1607
1608 return perm;
1609}
1610
1611/*
1612 * Check permission between a pair of credentials
1613 * fork check, ptrace check, etc.
1614 */
1615static int cred_has_perm(const struct cred *actor,
1616 const struct cred *target,
1617 u32 perms)
1618{
1619 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1620
1621 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1622}
1623
1624/*
1625 * Check permission between a pair of tasks, e.g. signal checks,
1626 * fork check, ptrace check, etc.
1627 * tsk1 is the actor and tsk2 is the target
1628 * - this uses the default subjective creds of tsk1
1629 */
1630static int task_has_perm(const struct task_struct *tsk1,
1631 const struct task_struct *tsk2,
1632 u32 perms)
1633{
1634 const struct task_security_struct *__tsec1, *__tsec2;
1635 u32 sid1, sid2;
1636
1637 rcu_read_lock();
1638 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1639 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1640 rcu_read_unlock();
1641 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1642}
1643
1644/*
1645 * Check permission between current and another task, e.g. signal checks,
1646 * fork check, ptrace check, etc.
1647 * current is the actor and tsk2 is the target
1648 * - this uses current's subjective creds
1649 */
1650static int current_has_perm(const struct task_struct *tsk,
1651 u32 perms)
1652{
1653 u32 sid, tsid;
1654
1655 sid = current_sid();
1656 tsid = task_sid(tsk);
1657 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1658}
1659
1660#if CAP_LAST_CAP > 63
1661#error Fix SELinux to handle capabilities > 63.
1662#endif
1663
1664/* Check whether a task is allowed to use a capability. */
1665static int cred_has_capability(const struct cred *cred,
1666 int cap, int audit, bool initns)
1667{
1668 struct common_audit_data ad;
1669 struct av_decision avd;
1670 u16 sclass;
1671 u32 sid = cred_sid(cred);
1672 u32 av = CAP_TO_MASK(cap);
1673 int rc;
1674
1675 ad.type = LSM_AUDIT_DATA_CAP;
1676 ad.u.cap = cap;
1677
1678 switch (CAP_TO_INDEX(cap)) {
1679 case 0:
1680 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1681 break;
1682 case 1:
1683 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1684 break;
1685 default:
1686 printk(KERN_ERR
1687 "SELinux: out of range capability %d\n", cap);
1688 BUG();
1689 return -EINVAL;
1690 }
1691
1692 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1693 if (audit == SECURITY_CAP_AUDIT) {
1694 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1695 if (rc2)
1696 return rc2;
1697 }
1698 return rc;
1699}
1700
1701/* Check whether a task is allowed to use a system operation. */
1702static int task_has_system(struct task_struct *tsk,
1703 u32 perms)
1704{
1705 u32 sid = task_sid(tsk);
1706
1707 return avc_has_perm(sid, SECINITSID_KERNEL,
1708 SECCLASS_SYSTEM, perms, NULL);
1709}
1710
1711/* Check whether a task has a particular permission to an inode.
1712 The 'adp' parameter is optional and allows other audit
1713 data to be passed (e.g. the dentry). */
1714static int inode_has_perm(const struct cred *cred,
1715 struct inode *inode,
1716 u32 perms,
1717 struct common_audit_data *adp)
1718{
1719 struct inode_security_struct *isec;
1720 u32 sid;
1721
1722 validate_creds(cred);
1723
1724 if (unlikely(IS_PRIVATE(inode)))
1725 return 0;
1726
1727 sid = cred_sid(cred);
1728 isec = inode->i_security;
1729
1730 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1731}
1732
1733/* Same as inode_has_perm, but pass explicit audit data containing
1734 the dentry to help the auditing code to more easily generate the
1735 pathname if needed. */
1736static inline int dentry_has_perm(const struct cred *cred,
1737 struct dentry *dentry,
1738 u32 av)
1739{
1740 struct inode *inode = d_backing_inode(dentry);
1741 struct common_audit_data ad;
1742
1743 ad.type = LSM_AUDIT_DATA_DENTRY;
1744 ad.u.dentry = dentry;
1745 __inode_security_revalidate(inode, dentry, true);
1746 return inode_has_perm(cred, inode, av, &ad);
1747}
1748
1749/* Same as inode_has_perm, but pass explicit audit data containing
1750 the path to help the auditing code to more easily generate the
1751 pathname if needed. */
1752static inline int path_has_perm(const struct cred *cred,
1753 const struct path *path,
1754 u32 av)
1755{
1756 struct inode *inode = d_backing_inode(path->dentry);
1757 struct common_audit_data ad;
1758
1759 ad.type = LSM_AUDIT_DATA_PATH;
1760 ad.u.path = *path;
1761 __inode_security_revalidate(inode, path->dentry, true);
1762 return inode_has_perm(cred, inode, av, &ad);
1763}
1764
1765/* Same as path_has_perm, but uses the inode from the file struct. */
1766static inline int file_path_has_perm(const struct cred *cred,
1767 struct file *file,
1768 u32 av)
1769{
1770 struct common_audit_data ad;
1771
1772 ad.type = LSM_AUDIT_DATA_FILE;
1773 ad.u.file = file;
1774 return inode_has_perm(cred, file_inode(file), av, &ad);
1775}
1776
1777/* Check whether a task can use an open file descriptor to
1778 access an inode in a given way. Check access to the
1779 descriptor itself, and then use dentry_has_perm to
1780 check a particular permission to the file.
1781 Access to the descriptor is implicitly granted if it
1782 has the same SID as the process. If av is zero, then
1783 access to the file is not checked, e.g. for cases
1784 where only the descriptor is affected like seek. */
1785static int file_has_perm(const struct cred *cred,
1786 struct file *file,
1787 u32 av)
1788{
1789 struct file_security_struct *fsec = file->f_security;
1790 struct inode *inode = file_inode(file);
1791 struct common_audit_data ad;
1792 u32 sid = cred_sid(cred);
1793 int rc;
1794
1795 ad.type = LSM_AUDIT_DATA_FILE;
1796 ad.u.file = file;
1797
1798 if (sid != fsec->sid) {
1799 rc = avc_has_perm(sid, fsec->sid,
1800 SECCLASS_FD,
1801 FD__USE,
1802 &ad);
1803 if (rc)
1804 goto out;
1805 }
1806
1807 /* av is zero if only checking access to the descriptor. */
1808 rc = 0;
1809 if (av)
1810 rc = inode_has_perm(cred, inode, av, &ad);
1811
1812out:
1813 return rc;
1814}
1815
1816/*
1817 * Determine the label for an inode that might be unioned.
1818 */
1819static int
1820selinux_determine_inode_label(const struct task_security_struct *tsec,
1821 struct inode *dir,
1822 const struct qstr *name, u16 tclass,
1823 u32 *_new_isid)
1824{
1825 const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1826
1827 if ((sbsec->flags & SE_SBINITIALIZED) &&
1828 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1829 *_new_isid = sbsec->mntpoint_sid;
1830 } else if ((sbsec->flags & SBLABEL_MNT) &&
1831 tsec->create_sid) {
1832 *_new_isid = tsec->create_sid;
1833 } else {
1834 const struct inode_security_struct *dsec = inode_security(dir);
1835 return security_transition_sid(tsec->sid, dsec->sid, tclass,
1836 name, _new_isid);
1837 }
1838
1839 return 0;
1840}
1841
1842/* Check whether a task can create a file. */
1843static int may_create(struct inode *dir,
1844 struct dentry *dentry,
1845 u16 tclass)
1846{
1847 const struct task_security_struct *tsec = current_security();
1848 struct inode_security_struct *dsec;
1849 struct superblock_security_struct *sbsec;
1850 u32 sid, newsid;
1851 struct common_audit_data ad;
1852 int rc;
1853
1854 dsec = inode_security(dir);
1855 sbsec = dir->i_sb->s_security;
1856
1857 sid = tsec->sid;
1858
1859 ad.type = LSM_AUDIT_DATA_DENTRY;
1860 ad.u.dentry = dentry;
1861
1862 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1863 DIR__ADD_NAME | DIR__SEARCH,
1864 &ad);
1865 if (rc)
1866 return rc;
1867
1868 rc = selinux_determine_inode_label(current_security(), dir,
1869 &dentry->d_name, tclass, &newsid);
1870 if (rc)
1871 return rc;
1872
1873 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1874 if (rc)
1875 return rc;
1876
1877 return avc_has_perm(newsid, sbsec->sid,
1878 SECCLASS_FILESYSTEM,
1879 FILESYSTEM__ASSOCIATE, &ad);
1880}
1881
1882/* Check whether a task can create a key. */
1883static int may_create_key(u32 ksid,
1884 struct task_struct *ctx)
1885{
1886 u32 sid = task_sid(ctx);
1887
1888 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1889}
1890
1891#define MAY_LINK 0
1892#define MAY_UNLINK 1
1893#define MAY_RMDIR 2
1894
1895/* Check whether a task can link, unlink, or rmdir a file/directory. */
1896static int may_link(struct inode *dir,
1897 struct dentry *dentry,
1898 int kind)
1899
1900{
1901 struct inode_security_struct *dsec, *isec;
1902 struct common_audit_data ad;
1903 u32 sid = current_sid();
1904 u32 av;
1905 int rc;
1906
1907 dsec = inode_security(dir);
1908 isec = backing_inode_security(dentry);
1909
1910 ad.type = LSM_AUDIT_DATA_DENTRY;
1911 ad.u.dentry = dentry;
1912
1913 av = DIR__SEARCH;
1914 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1915 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1916 if (rc)
1917 return rc;
1918
1919 switch (kind) {
1920 case MAY_LINK:
1921 av = FILE__LINK;
1922 break;
1923 case MAY_UNLINK:
1924 av = FILE__UNLINK;
1925 break;
1926 case MAY_RMDIR:
1927 av = DIR__RMDIR;
1928 break;
1929 default:
1930 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1931 __func__, kind);
1932 return 0;
1933 }
1934
1935 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1936 return rc;
1937}
1938
1939static inline int may_rename(struct inode *old_dir,
1940 struct dentry *old_dentry,
1941 struct inode *new_dir,
1942 struct dentry *new_dentry)
1943{
1944 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1945 struct common_audit_data ad;
1946 u32 sid = current_sid();
1947 u32 av;
1948 int old_is_dir, new_is_dir;
1949 int rc;
1950
1951 old_dsec = inode_security(old_dir);
1952 old_isec = backing_inode_security(old_dentry);
1953 old_is_dir = d_is_dir(old_dentry);
1954 new_dsec = inode_security(new_dir);
1955
1956 ad.type = LSM_AUDIT_DATA_DENTRY;
1957
1958 ad.u.dentry = old_dentry;
1959 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1960 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1961 if (rc)
1962 return rc;
1963 rc = avc_has_perm(sid, old_isec->sid,
1964 old_isec->sclass, FILE__RENAME, &ad);
1965 if (rc)
1966 return rc;
1967 if (old_is_dir && new_dir != old_dir) {
1968 rc = avc_has_perm(sid, old_isec->sid,
1969 old_isec->sclass, DIR__REPARENT, &ad);
1970 if (rc)
1971 return rc;
1972 }
1973
1974 ad.u.dentry = new_dentry;
1975 av = DIR__ADD_NAME | DIR__SEARCH;
1976 if (d_is_positive(new_dentry))
1977 av |= DIR__REMOVE_NAME;
1978 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1979 if (rc)
1980 return rc;
1981 if (d_is_positive(new_dentry)) {
1982 new_isec = backing_inode_security(new_dentry);
1983 new_is_dir = d_is_dir(new_dentry);
1984 rc = avc_has_perm(sid, new_isec->sid,
1985 new_isec->sclass,
1986 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1987 if (rc)
1988 return rc;
1989 }
1990
1991 return 0;
1992}
1993
1994/* Check whether a task can perform a filesystem operation. */
1995static int superblock_has_perm(const struct cred *cred,
1996 struct super_block *sb,
1997 u32 perms,
1998 struct common_audit_data *ad)
1999{
2000 struct superblock_security_struct *sbsec;
2001 u32 sid = cred_sid(cred);
2002
2003 sbsec = sb->s_security;
2004 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
2005}
2006
2007/* Convert a Linux mode and permission mask to an access vector. */
2008static inline u32 file_mask_to_av(int mode, int mask)
2009{
2010 u32 av = 0;
2011
2012 if (!S_ISDIR(mode)) {
2013 if (mask & MAY_EXEC)
2014 av |= FILE__EXECUTE;
2015 if (mask & MAY_READ)
2016 av |= FILE__READ;
2017
2018 if (mask & MAY_APPEND)
2019 av |= FILE__APPEND;
2020 else if (mask & MAY_WRITE)
2021 av |= FILE__WRITE;
2022
2023 } else {
2024 if (mask & MAY_EXEC)
2025 av |= DIR__SEARCH;
2026 if (mask & MAY_WRITE)
2027 av |= DIR__WRITE;
2028 if (mask & MAY_READ)
2029 av |= DIR__READ;
2030 }
2031
2032 return av;
2033}
2034
2035/* Convert a Linux file to an access vector. */
2036static inline u32 file_to_av(struct file *file)
2037{
2038 u32 av = 0;
2039
2040 if (file->f_mode & FMODE_READ)
2041 av |= FILE__READ;
2042 if (file->f_mode & FMODE_WRITE) {
2043 if (file->f_flags & O_APPEND)
2044 av |= FILE__APPEND;
2045 else
2046 av |= FILE__WRITE;
2047 }
2048 if (!av) {
2049 /*
2050 * Special file opened with flags 3 for ioctl-only use.
2051 */
2052 av = FILE__IOCTL;
2053 }
2054
2055 return av;
2056}
2057
2058/*
2059 * Convert a file to an access vector and include the correct open
2060 * open permission.
2061 */
2062static inline u32 open_file_to_av(struct file *file)
2063{
2064 u32 av = file_to_av(file);
2065
2066 if (selinux_policycap_openperm)
2067 av |= FILE__OPEN;
2068
2069 return av;
2070}
2071
2072/* Hook functions begin here. */
2073
2074static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2075{
2076 u32 mysid = current_sid();
2077 u32 mgrsid = task_sid(mgr);
2078
2079 return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER,
2080 BINDER__SET_CONTEXT_MGR, NULL);
2081}
2082
2083static int selinux_binder_transaction(struct task_struct *from,
2084 struct task_struct *to)
2085{
2086 u32 mysid = current_sid();
2087 u32 fromsid = task_sid(from);
2088 u32 tosid = task_sid(to);
2089 int rc;
2090
2091 if (mysid != fromsid) {
2092 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2093 BINDER__IMPERSONATE, NULL);
2094 if (rc)
2095 return rc;
2096 }
2097
2098 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2099 NULL);
2100}
2101
2102static int selinux_binder_transfer_binder(struct task_struct *from,
2103 struct task_struct *to)
2104{
2105 u32 fromsid = task_sid(from);
2106 u32 tosid = task_sid(to);
2107
2108 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2109 NULL);
2110}
2111
2112static int selinux_binder_transfer_file(struct task_struct *from,
2113 struct task_struct *to,
2114 struct file *file)
2115{
2116 u32 sid = task_sid(to);
2117 struct file_security_struct *fsec = file->f_security;
2118 struct dentry *dentry = file->f_path.dentry;
2119 struct inode_security_struct *isec;
2120 struct common_audit_data ad;
2121 int rc;
2122
2123 ad.type = LSM_AUDIT_DATA_PATH;
2124 ad.u.path = file->f_path;
2125
2126 if (sid != fsec->sid) {
2127 rc = avc_has_perm(sid, fsec->sid,
2128 SECCLASS_FD,
2129 FD__USE,
2130 &ad);
2131 if (rc)
2132 return rc;
2133 }
2134
2135 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2136 return 0;
2137
2138 isec = backing_inode_security(dentry);
2139 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2140 &ad);
2141}
2142
2143static int selinux_ptrace_access_check(struct task_struct *child,
2144 unsigned int mode)
2145{
2146 if (mode & PTRACE_MODE_READ) {
2147 u32 sid = current_sid();
2148 u32 csid = task_sid(child);
2149 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2150 }
2151
2152 return current_has_perm(child, PROCESS__PTRACE);
2153}
2154
2155static int selinux_ptrace_traceme(struct task_struct *parent)
2156{
2157 return task_has_perm(parent, current, PROCESS__PTRACE);
2158}
2159
2160static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2161 kernel_cap_t *inheritable, kernel_cap_t *permitted)
2162{
2163 return current_has_perm(target, PROCESS__GETCAP);
2164}
2165
2166static int selinux_capset(struct cred *new, const struct cred *old,
2167 const kernel_cap_t *effective,
2168 const kernel_cap_t *inheritable,
2169 const kernel_cap_t *permitted)
2170{
2171 return cred_has_perm(old, new, PROCESS__SETCAP);
2172}
2173
2174/*
2175 * (This comment used to live with the selinux_task_setuid hook,
2176 * which was removed).
2177 *
2178 * Since setuid only affects the current process, and since the SELinux
2179 * controls are not based on the Linux identity attributes, SELinux does not
2180 * need to control this operation. However, SELinux does control the use of
2181 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2182 */
2183
2184static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2185 int cap, int audit)
2186{
2187 return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
2188}
2189
2190static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2191{
2192 const struct cred *cred = current_cred();
2193 int rc = 0;
2194
2195 if (!sb)
2196 return 0;
2197
2198 switch (cmds) {
2199 case Q_SYNC:
2200 case Q_QUOTAON:
2201 case Q_QUOTAOFF:
2202 case Q_SETINFO:
2203 case Q_SETQUOTA:
2204 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2205 break;
2206 case Q_GETFMT:
2207 case Q_GETINFO:
2208 case Q_GETQUOTA:
2209 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2210 break;
2211 default:
2212 rc = 0; /* let the kernel handle invalid cmds */
2213 break;
2214 }
2215 return rc;
2216}
2217
2218static int selinux_quota_on(struct dentry *dentry)
2219{
2220 const struct cred *cred = current_cred();
2221
2222 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2223}
2224
2225static int selinux_syslog(int type)
2226{
2227 int rc;
2228
2229 switch (type) {
2230 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2231 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2232 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2233 break;
2234 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2235 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2236 /* Set level of messages printed to console */
2237 case SYSLOG_ACTION_CONSOLE_LEVEL:
2238 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2239 break;
2240 case SYSLOG_ACTION_CLOSE: /* Close log */
2241 case SYSLOG_ACTION_OPEN: /* Open log */
2242 case SYSLOG_ACTION_READ: /* Read from log */
2243 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
2244 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
2245 default:
2246 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2247 break;
2248 }
2249 return rc;
2250}
2251
2252/*
2253 * Check that a process has enough memory to allocate a new virtual
2254 * mapping. 0 means there is enough memory for the allocation to
2255 * succeed and -ENOMEM implies there is not.
2256 *
2257 * Do not audit the selinux permission check, as this is applied to all
2258 * processes that allocate mappings.
2259 */
2260static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2261{
2262 int rc, cap_sys_admin = 0;
2263
2264 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2265 SECURITY_CAP_NOAUDIT, true);
2266 if (rc == 0)
2267 cap_sys_admin = 1;
2268
2269 return cap_sys_admin;
2270}
2271
2272/* binprm security operations */
2273
2274static u32 ptrace_parent_sid(struct task_struct *task)
2275{
2276 u32 sid = 0;
2277 struct task_struct *tracer;
2278
2279 rcu_read_lock();
2280 tracer = ptrace_parent(task);
2281 if (tracer)
2282 sid = task_sid(tracer);
2283 rcu_read_unlock();
2284
2285 return sid;
2286}
2287
2288static int check_nnp_nosuid(const struct linux_binprm *bprm,
2289 const struct task_security_struct *old_tsec,
2290 const struct task_security_struct *new_tsec)
2291{
2292 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2293 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2294 int rc;
2295
2296 if (!nnp && !nosuid)
2297 return 0; /* neither NNP nor nosuid */
2298
2299 if (new_tsec->sid == old_tsec->sid)
2300 return 0; /* No change in credentials */
2301
2302 /*
2303 * The only transitions we permit under NNP or nosuid
2304 * are transitions to bounded SIDs, i.e. SIDs that are
2305 * guaranteed to only be allowed a subset of the permissions
2306 * of the current SID.
2307 */
2308 rc = security_bounded_transition(old_tsec->sid, new_tsec->sid);
2309 if (rc) {
2310 /*
2311 * On failure, preserve the errno values for NNP vs nosuid.
2312 * NNP: Operation not permitted for caller.
2313 * nosuid: Permission denied to file.
2314 */
2315 if (nnp)
2316 return -EPERM;
2317 else
2318 return -EACCES;
2319 }
2320 return 0;
2321}
2322
2323static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2324{
2325 const struct task_security_struct *old_tsec;
2326 struct task_security_struct *new_tsec;
2327 struct inode_security_struct *isec;
2328 struct common_audit_data ad;
2329 struct inode *inode = file_inode(bprm->file);
2330 int rc;
2331
2332 /* SELinux context only depends on initial program or script and not
2333 * the script interpreter */
2334 if (bprm->cred_prepared)
2335 return 0;
2336
2337 old_tsec = current_security();
2338 new_tsec = bprm->cred->security;
2339 isec = inode_security(inode);
2340
2341 /* Default to the current task SID. */
2342 new_tsec->sid = old_tsec->sid;
2343 new_tsec->osid = old_tsec->sid;
2344
2345 /* Reset fs, key, and sock SIDs on execve. */
2346 new_tsec->create_sid = 0;
2347 new_tsec->keycreate_sid = 0;
2348 new_tsec->sockcreate_sid = 0;
2349
2350 if (old_tsec->exec_sid) {
2351 new_tsec->sid = old_tsec->exec_sid;
2352 /* Reset exec SID on execve. */
2353 new_tsec->exec_sid = 0;
2354
2355 /* Fail on NNP or nosuid if not an allowed transition. */
2356 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2357 if (rc)
2358 return rc;
2359 } else {
2360 /* Check for a default transition on this program. */
2361 rc = security_transition_sid(old_tsec->sid, isec->sid,
2362 SECCLASS_PROCESS, NULL,
2363 &new_tsec->sid);
2364 if (rc)
2365 return rc;
2366
2367 /*
2368 * Fallback to old SID on NNP or nosuid if not an allowed
2369 * transition.
2370 */
2371 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2372 if (rc)
2373 new_tsec->sid = old_tsec->sid;
2374 }
2375
2376 ad.type = LSM_AUDIT_DATA_FILE;
2377 ad.u.file = bprm->file;
2378
2379 if (new_tsec->sid == old_tsec->sid) {
2380 rc = avc_has_perm(old_tsec->sid, isec->sid,
2381 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2382 if (rc)
2383 return rc;
2384 } else {
2385 /* Check permissions for the transition. */
2386 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2387 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2388 if (rc)
2389 return rc;
2390
2391 rc = avc_has_perm(new_tsec->sid, isec->sid,
2392 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2393 if (rc)
2394 return rc;
2395
2396 /* Check for shared state */
2397 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2398 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2399 SECCLASS_PROCESS, PROCESS__SHARE,
2400 NULL);
2401 if (rc)
2402 return -EPERM;
2403 }
2404
2405 /* Make sure that anyone attempting to ptrace over a task that
2406 * changes its SID has the appropriate permit */
2407 if (bprm->unsafe &
2408 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2409 u32 ptsid = ptrace_parent_sid(current);
2410 if (ptsid != 0) {
2411 rc = avc_has_perm(ptsid, new_tsec->sid,
2412 SECCLASS_PROCESS,
2413 PROCESS__PTRACE, NULL);
2414 if (rc)
2415 return -EPERM;
2416 }
2417 }
2418
2419 /* Clear any possibly unsafe personality bits on exec: */
2420 bprm->per_clear |= PER_CLEAR_ON_SETID;
2421 }
2422
2423 return 0;
2424}
2425
2426static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2427{
2428 const struct task_security_struct *tsec = current_security();
2429 u32 sid, osid;
2430 int atsecure = 0;
2431
2432 sid = tsec->sid;
2433 osid = tsec->osid;
2434
2435 if (osid != sid) {
2436 /* Enable secure mode for SIDs transitions unless
2437 the noatsecure permission is granted between
2438 the two SIDs, i.e. ahp returns 0. */
2439 atsecure = avc_has_perm(osid, sid,
2440 SECCLASS_PROCESS,
2441 PROCESS__NOATSECURE, NULL);
2442 }
2443
2444 return !!atsecure;
2445}
2446
2447static int match_file(const void *p, struct file *file, unsigned fd)
2448{
2449 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2450}
2451
2452/* Derived from fs/exec.c:flush_old_files. */
2453static inline void flush_unauthorized_files(const struct cred *cred,
2454 struct files_struct *files)
2455{
2456 struct file *file, *devnull = NULL;
2457 struct tty_struct *tty;
2458 int drop_tty = 0;
2459 unsigned n;
2460
2461 tty = get_current_tty();
2462 if (tty) {
2463 spin_lock(&tty->files_lock);
2464 if (!list_empty(&tty->tty_files)) {
2465 struct tty_file_private *file_priv;
2466
2467 /* Revalidate access to controlling tty.
2468 Use file_path_has_perm on the tty path directly
2469 rather than using file_has_perm, as this particular
2470 open file may belong to another process and we are
2471 only interested in the inode-based check here. */
2472 file_priv = list_first_entry(&tty->tty_files,
2473 struct tty_file_private, list);
2474 file = file_priv->file;
2475 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2476 drop_tty = 1;
2477 }
2478 spin_unlock(&tty->files_lock);
2479 tty_kref_put(tty);
2480 }
2481 /* Reset controlling tty. */
2482 if (drop_tty)
2483 no_tty();
2484
2485 /* Revalidate access to inherited open files. */
2486 n = iterate_fd(files, 0, match_file, cred);
2487 if (!n) /* none found? */
2488 return;
2489
2490 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2491 if (IS_ERR(devnull))
2492 devnull = NULL;
2493 /* replace all the matching ones with this */
2494 do {
2495 replace_fd(n - 1, devnull, 0);
2496 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2497 if (devnull)
2498 fput(devnull);
2499}
2500
2501/*
2502 * Prepare a process for imminent new credential changes due to exec
2503 */
2504static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2505{
2506 struct task_security_struct *new_tsec;
2507 struct rlimit *rlim, *initrlim;
2508 int rc, i;
2509
2510 new_tsec = bprm->cred->security;
2511 if (new_tsec->sid == new_tsec->osid)
2512 return;
2513
2514 /* Close files for which the new task SID is not authorized. */
2515 flush_unauthorized_files(bprm->cred, current->files);
2516
2517 /* Always clear parent death signal on SID transitions. */
2518 current->pdeath_signal = 0;
2519
2520 /* Check whether the new SID can inherit resource limits from the old
2521 * SID. If not, reset all soft limits to the lower of the current
2522 * task's hard limit and the init task's soft limit.
2523 *
2524 * Note that the setting of hard limits (even to lower them) can be
2525 * controlled by the setrlimit check. The inclusion of the init task's
2526 * soft limit into the computation is to avoid resetting soft limits
2527 * higher than the default soft limit for cases where the default is
2528 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2529 */
2530 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2531 PROCESS__RLIMITINH, NULL);
2532 if (rc) {
2533 /* protect against do_prlimit() */
2534 task_lock(current);
2535 for (i = 0; i < RLIM_NLIMITS; i++) {
2536 rlim = current->signal->rlim + i;
2537 initrlim = init_task.signal->rlim + i;
2538 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2539 }
2540 task_unlock(current);
2541 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2542 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2543 }
2544}
2545
2546/*
2547 * Clean up the process immediately after the installation of new credentials
2548 * due to exec
2549 */
2550static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2551{
2552 const struct task_security_struct *tsec = current_security();
2553 struct itimerval itimer;
2554 u32 osid, sid;
2555 int rc, i;
2556
2557 osid = tsec->osid;
2558 sid = tsec->sid;
2559
2560 if (sid == osid)
2561 return;
2562
2563 /* Check whether the new SID can inherit signal state from the old SID.
2564 * If not, clear itimers to avoid subsequent signal generation and
2565 * flush and unblock signals.
2566 *
2567 * This must occur _after_ the task SID has been updated so that any
2568 * kill done after the flush will be checked against the new SID.
2569 */
2570 rc = avc_has_perm(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 match_prefix(char *prefix, int plen, char *option, int olen)
2608{
2609 if (plen > olen)
2610 return 0;
2611
2612 return !memcmp(prefix, option, plen);
2613}
2614
2615static inline int selinux_option(char *option, int len)
2616{
2617 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2618 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2619 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2620 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2621 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2622}
2623
2624static inline void take_option(char **to, char *from, int *first, int len)
2625{
2626 if (!*first) {
2627 **to = ',';
2628 *to += 1;
2629 } else
2630 *first = 0;
2631 memcpy(*to, from, len);
2632 *to += len;
2633}
2634
2635static inline void take_selinux_option(char **to, char *from, int *first,
2636 int len)
2637{
2638 int current_size = 0;
2639
2640 if (!*first) {
2641 **to = '|';
2642 *to += 1;
2643 } else
2644 *first = 0;
2645
2646 while (current_size < len) {
2647 if (*from != '"') {
2648 **to = *from;
2649 *to += 1;
2650 }
2651 from += 1;
2652 current_size += 1;
2653 }
2654}
2655
2656static int selinux_sb_copy_data(char *orig, char *copy)
2657{
2658 int fnosec, fsec, rc = 0;
2659 char *in_save, *in_curr, *in_end;
2660 char *sec_curr, *nosec_save, *nosec;
2661 int open_quote = 0;
2662
2663 in_curr = orig;
2664 sec_curr = copy;
2665
2666 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2667 if (!nosec) {
2668 rc = -ENOMEM;
2669 goto out;
2670 }
2671
2672 nosec_save = nosec;
2673 fnosec = fsec = 1;
2674 in_save = in_end = orig;
2675
2676 do {
2677 if (*in_end == '"')
2678 open_quote = !open_quote;
2679 if ((*in_end == ',' && open_quote == 0) ||
2680 *in_end == '\0') {
2681 int len = in_end - in_curr;
2682
2683 if (selinux_option(in_curr, len))
2684 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2685 else
2686 take_option(&nosec, in_curr, &fnosec, len);
2687
2688 in_curr = in_end + 1;
2689 }
2690 } while (*in_end++);
2691
2692 strcpy(in_save, nosec_save);
2693 free_page((unsigned long)nosec_save);
2694out:
2695 return rc;
2696}
2697
2698static int selinux_sb_remount(struct super_block *sb, void *data)
2699{
2700 int rc, i, *flags;
2701 struct security_mnt_opts opts;
2702 char *secdata, **mount_options;
2703 struct superblock_security_struct *sbsec = sb->s_security;
2704
2705 if (!(sbsec->flags & SE_SBINITIALIZED))
2706 return 0;
2707
2708 if (!data)
2709 return 0;
2710
2711 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2712 return 0;
2713
2714 security_init_mnt_opts(&opts);
2715 secdata = alloc_secdata();
2716 if (!secdata)
2717 return -ENOMEM;
2718 rc = selinux_sb_copy_data(data, secdata);
2719 if (rc)
2720 goto out_free_secdata;
2721
2722 rc = selinux_parse_opts_str(secdata, &opts);
2723 if (rc)
2724 goto out_free_secdata;
2725
2726 mount_options = opts.mnt_opts;
2727 flags = opts.mnt_opts_flags;
2728
2729 for (i = 0; i < opts.num_mnt_opts; i++) {
2730 u32 sid;
2731
2732 if (flags[i] == SBLABEL_MNT)
2733 continue;
2734 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
2735 if (rc) {
2736 printk(KERN_WARNING "SELinux: security_context_str_to_sid"
2737 "(%s) failed for (dev %s, type %s) errno=%d\n",
2738 mount_options[i], sb->s_id, sb->s_type->name, rc);
2739 goto out_free_opts;
2740 }
2741 rc = -EINVAL;
2742 switch (flags[i]) {
2743 case FSCONTEXT_MNT:
2744 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2745 goto out_bad_option;
2746 break;
2747 case CONTEXT_MNT:
2748 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2749 goto out_bad_option;
2750 break;
2751 case ROOTCONTEXT_MNT: {
2752 struct inode_security_struct *root_isec;
2753 root_isec = backing_inode_security(sb->s_root);
2754
2755 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2756 goto out_bad_option;
2757 break;
2758 }
2759 case DEFCONTEXT_MNT:
2760 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2761 goto out_bad_option;
2762 break;
2763 default:
2764 goto out_free_opts;
2765 }
2766 }
2767
2768 rc = 0;
2769out_free_opts:
2770 security_free_mnt_opts(&opts);
2771out_free_secdata:
2772 free_secdata(secdata);
2773 return rc;
2774out_bad_option:
2775 printk(KERN_WARNING "SELinux: unable to change security options "
2776 "during remount (dev %s, type=%s)\n", sb->s_id,
2777 sb->s_type->name);
2778 goto out_free_opts;
2779}
2780
2781static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2782{
2783 const struct cred *cred = current_cred();
2784 struct common_audit_data ad;
2785 int rc;
2786
2787 rc = superblock_doinit(sb, data);
2788 if (rc)
2789 return rc;
2790
2791 /* Allow all mounts performed by the kernel */
2792 if (flags & MS_KERNMOUNT)
2793 return 0;
2794
2795 ad.type = LSM_AUDIT_DATA_DENTRY;
2796 ad.u.dentry = sb->s_root;
2797 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2798}
2799
2800static int selinux_sb_statfs(struct dentry *dentry)
2801{
2802 const struct cred *cred = current_cred();
2803 struct common_audit_data ad;
2804
2805 ad.type = LSM_AUDIT_DATA_DENTRY;
2806 ad.u.dentry = dentry->d_sb->s_root;
2807 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2808}
2809
2810static int selinux_mount(const char *dev_name,
2811 const struct path *path,
2812 const char *type,
2813 unsigned long flags,
2814 void *data)
2815{
2816 const struct cred *cred = current_cred();
2817
2818 if (flags & MS_REMOUNT)
2819 return superblock_has_perm(cred, path->dentry->d_sb,
2820 FILESYSTEM__REMOUNT, NULL);
2821 else
2822 return path_has_perm(cred, path, FILE__MOUNTON);
2823}
2824
2825static int selinux_umount(struct vfsmount *mnt, int flags)
2826{
2827 const struct cred *cred = current_cred();
2828
2829 return superblock_has_perm(cred, mnt->mnt_sb,
2830 FILESYSTEM__UNMOUNT, NULL);
2831}
2832
2833/* inode security operations */
2834
2835static int selinux_inode_alloc_security(struct inode *inode)
2836{
2837 return inode_alloc_security(inode);
2838}
2839
2840static void selinux_inode_free_security(struct inode *inode)
2841{
2842 inode_free_security(inode);
2843}
2844
2845static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2846 const struct qstr *name, void **ctx,
2847 u32 *ctxlen)
2848{
2849 u32 newsid;
2850 int rc;
2851
2852 rc = selinux_determine_inode_label(current_security(),
2853 d_inode(dentry->d_parent), name,
2854 inode_mode_to_security_class(mode),
2855 &newsid);
2856 if (rc)
2857 return rc;
2858
2859 return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2860}
2861
2862static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2863 struct qstr *name,
2864 const struct cred *old,
2865 struct cred *new)
2866{
2867 u32 newsid;
2868 int rc;
2869 struct task_security_struct *tsec;
2870
2871 rc = selinux_determine_inode_label(old->security,
2872 d_inode(dentry->d_parent), name,
2873 inode_mode_to_security_class(mode),
2874 &newsid);
2875 if (rc)
2876 return rc;
2877
2878 tsec = new->security;
2879 tsec->create_sid = newsid;
2880 return 0;
2881}
2882
2883static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2884 const struct qstr *qstr,
2885 const char **name,
2886 void **value, size_t *len)
2887{
2888 const struct task_security_struct *tsec = current_security();
2889 struct superblock_security_struct *sbsec;
2890 u32 sid, newsid, clen;
2891 int rc;
2892 char *context;
2893
2894 sbsec = dir->i_sb->s_security;
2895
2896 sid = tsec->sid;
2897 newsid = tsec->create_sid;
2898
2899 rc = selinux_determine_inode_label(current_security(),
2900 dir, qstr,
2901 inode_mode_to_security_class(inode->i_mode),
2902 &newsid);
2903 if (rc)
2904 return rc;
2905
2906 /* Possibly defer initialization to selinux_complete_init. */
2907 if (sbsec->flags & SE_SBINITIALIZED) {
2908 struct inode_security_struct *isec = inode->i_security;
2909 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2910 isec->sid = newsid;
2911 isec->initialized = LABEL_INITIALIZED;
2912 }
2913
2914 if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2915 return -EOPNOTSUPP;
2916
2917 if (name)
2918 *name = XATTR_SELINUX_SUFFIX;
2919
2920 if (value && len) {
2921 rc = security_sid_to_context_force(newsid, &context, &clen);
2922 if (rc)
2923 return rc;
2924 *value = context;
2925 *len = clen;
2926 }
2927
2928 return 0;
2929}
2930
2931static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2932{
2933 return may_create(dir, dentry, SECCLASS_FILE);
2934}
2935
2936static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2937{
2938 return may_link(dir, old_dentry, MAY_LINK);
2939}
2940
2941static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2942{
2943 return may_link(dir, dentry, MAY_UNLINK);
2944}
2945
2946static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2947{
2948 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2949}
2950
2951static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2952{
2953 return may_create(dir, dentry, SECCLASS_DIR);
2954}
2955
2956static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2957{
2958 return may_link(dir, dentry, MAY_RMDIR);
2959}
2960
2961static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2962{
2963 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2964}
2965
2966static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2967 struct inode *new_inode, struct dentry *new_dentry)
2968{
2969 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2970}
2971
2972static int selinux_inode_readlink(struct dentry *dentry)
2973{
2974 const struct cred *cred = current_cred();
2975
2976 return dentry_has_perm(cred, dentry, FILE__READ);
2977}
2978
2979static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2980 bool rcu)
2981{
2982 const struct cred *cred = current_cred();
2983 struct common_audit_data ad;
2984 struct inode_security_struct *isec;
2985 u32 sid;
2986
2987 validate_creds(cred);
2988
2989 ad.type = LSM_AUDIT_DATA_DENTRY;
2990 ad.u.dentry = dentry;
2991 sid = cred_sid(cred);
2992 isec = inode_security_rcu(inode, rcu);
2993 if (IS_ERR(isec))
2994 return PTR_ERR(isec);
2995
2996 return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad,
2997 rcu ? MAY_NOT_BLOCK : 0);
2998}
2999
3000static noinline int audit_inode_permission(struct inode *inode,
3001 u32 perms, u32 audited, u32 denied,
3002 int result,
3003 unsigned flags)
3004{
3005 struct common_audit_data ad;
3006 struct inode_security_struct *isec = inode->i_security;
3007 int rc;
3008
3009 ad.type = LSM_AUDIT_DATA_INODE;
3010 ad.u.inode = inode;
3011
3012 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3013 audited, denied, result, &ad, flags);
3014 if (rc)
3015 return rc;
3016 return 0;
3017}
3018
3019static int selinux_inode_permission(struct inode *inode, int mask)
3020{
3021 const struct cred *cred = current_cred();
3022 u32 perms;
3023 bool from_access;
3024 unsigned flags = mask & MAY_NOT_BLOCK;
3025 struct inode_security_struct *isec;
3026 u32 sid;
3027 struct av_decision avd;
3028 int rc, rc2;
3029 u32 audited, denied;
3030
3031 from_access = mask & MAY_ACCESS;
3032 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3033
3034 /* No permission to check. Existence test. */
3035 if (!mask)
3036 return 0;
3037
3038 validate_creds(cred);
3039
3040 if (unlikely(IS_PRIVATE(inode)))
3041 return 0;
3042
3043 perms = file_mask_to_av(inode->i_mode, mask);
3044
3045 sid = cred_sid(cred);
3046 isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
3047 if (IS_ERR(isec))
3048 return PTR_ERR(isec);
3049
3050 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
3051 audited = avc_audit_required(perms, &avd, rc,
3052 from_access ? FILE__AUDIT_ACCESS : 0,
3053 &denied);
3054 if (likely(!audited))
3055 return rc;
3056
3057 rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
3058 if (rc2)
3059 return rc2;
3060 return rc;
3061}
3062
3063static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3064{
3065 const struct cred *cred = current_cred();
3066 unsigned int ia_valid = iattr->ia_valid;
3067 __u32 av = FILE__WRITE;
3068
3069 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3070 if (ia_valid & ATTR_FORCE) {
3071 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3072 ATTR_FORCE);
3073 if (!ia_valid)
3074 return 0;
3075 }
3076
3077 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3078 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3079 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3080
3081 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE)
3082 && !(ia_valid & ATTR_FILE))
3083 av |= FILE__OPEN;
3084
3085 return dentry_has_perm(cred, dentry, av);
3086}
3087
3088static int selinux_inode_getattr(const struct path *path)
3089{
3090 return path_has_perm(current_cred(), path, FILE__GETATTR);
3091}
3092
3093static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
3094{
3095 const struct cred *cred = current_cred();
3096
3097 if (!strncmp(name, XATTR_SECURITY_PREFIX,
3098 sizeof XATTR_SECURITY_PREFIX - 1)) {
3099 if (!strcmp(name, XATTR_NAME_CAPS)) {
3100 if (!capable(CAP_SETFCAP))
3101 return -EPERM;
3102 } else if (!capable(CAP_SYS_ADMIN)) {
3103 /* A different attribute in the security namespace.
3104 Restrict to administrator. */
3105 return -EPERM;
3106 }
3107 }
3108
3109 /* Not an attribute we recognize, so just check the
3110 ordinary setattr permission. */
3111 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3112}
3113
3114static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3115 const void *value, size_t size, int flags)
3116{
3117 struct inode *inode = d_backing_inode(dentry);
3118 struct inode_security_struct *isec;
3119 struct superblock_security_struct *sbsec;
3120 struct common_audit_data ad;
3121 u32 newsid, sid = current_sid();
3122 int rc = 0;
3123
3124 if (strcmp(name, XATTR_NAME_SELINUX))
3125 return selinux_inode_setotherxattr(dentry, name);
3126
3127 sbsec = inode->i_sb->s_security;
3128 if (!(sbsec->flags & SBLABEL_MNT))
3129 return -EOPNOTSUPP;
3130
3131 if (!inode_owner_or_capable(inode))
3132 return -EPERM;
3133
3134 ad.type = LSM_AUDIT_DATA_DENTRY;
3135 ad.u.dentry = dentry;
3136
3137 isec = backing_inode_security(dentry);
3138 rc = avc_has_perm(sid, isec->sid, isec->sclass,
3139 FILE__RELABELFROM, &ad);
3140 if (rc)
3141 return rc;
3142
3143 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3144 if (rc == -EINVAL) {
3145 if (!capable(CAP_MAC_ADMIN)) {
3146 struct audit_buffer *ab;
3147 size_t audit_size;
3148 const char *str;
3149
3150 /* We strip a nul only if it is at the end, otherwise the
3151 * context contains a nul and we should audit that */
3152 if (value) {
3153 str = value;
3154 if (str[size - 1] == '\0')
3155 audit_size = size - 1;
3156 else
3157 audit_size = size;
3158 } else {
3159 str = "";
3160 audit_size = 0;
3161 }
3162 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
3163 audit_log_format(ab, "op=setxattr invalid_context=");
3164 audit_log_n_untrustedstring(ab, value, audit_size);
3165 audit_log_end(ab);
3166
3167 return rc;
3168 }
3169 rc = security_context_to_sid_force(value, size, &newsid);
3170 }
3171 if (rc)
3172 return rc;
3173
3174 rc = avc_has_perm(sid, newsid, isec->sclass,
3175 FILE__RELABELTO, &ad);
3176 if (rc)
3177 return rc;
3178
3179 rc = security_validate_transition(isec->sid, newsid, sid,
3180 isec->sclass);
3181 if (rc)
3182 return rc;
3183
3184 return avc_has_perm(newsid,
3185 sbsec->sid,
3186 SECCLASS_FILESYSTEM,
3187 FILESYSTEM__ASSOCIATE,
3188 &ad);
3189}
3190
3191static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3192 const void *value, size_t size,
3193 int flags)
3194{
3195 struct inode *inode = d_backing_inode(dentry);
3196 struct inode_security_struct *isec;
3197 u32 newsid;
3198 int rc;
3199
3200 if (strcmp(name, XATTR_NAME_SELINUX)) {
3201 /* Not an attribute we recognize, so nothing to do. */
3202 return;
3203 }
3204
3205 rc = security_context_to_sid_force(value, size, &newsid);
3206 if (rc) {
3207 printk(KERN_ERR "SELinux: unable to map context to SID"
3208 "for (%s, %lu), rc=%d\n",
3209 inode->i_sb->s_id, inode->i_ino, -rc);
3210 return;
3211 }
3212
3213 isec = backing_inode_security(dentry);
3214 spin_lock(&isec->lock);
3215 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3216 isec->sid = newsid;
3217 isec->initialized = LABEL_INITIALIZED;
3218 spin_unlock(&isec->lock);
3219
3220 return;
3221}
3222
3223static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3224{
3225 const struct cred *cred = current_cred();
3226
3227 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3228}
3229
3230static int selinux_inode_listxattr(struct dentry *dentry)
3231{
3232 const struct cred *cred = current_cred();
3233
3234 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3235}
3236
3237static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3238{
3239 if (strcmp(name, XATTR_NAME_SELINUX))
3240 return selinux_inode_setotherxattr(dentry, name);
3241
3242 /* No one is allowed to remove a SELinux security label.
3243 You can change the label, but all data must be labeled. */
3244 return -EACCES;
3245}
3246
3247/*
3248 * Copy the inode security context value to the user.
3249 *
3250 * Permission check is handled by selinux_inode_getxattr hook.
3251 */
3252static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3253{
3254 u32 size;
3255 int error;
3256 char *context = NULL;
3257 struct inode_security_struct *isec;
3258
3259 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3260 return -EOPNOTSUPP;
3261
3262 /*
3263 * If the caller has CAP_MAC_ADMIN, then get the raw context
3264 * value even if it is not defined by current policy; otherwise,
3265 * use the in-core value under current policy.
3266 * Use the non-auditing forms of the permission checks since
3267 * getxattr may be called by unprivileged processes commonly
3268 * and lack of permission just means that we fall back to the
3269 * in-core context value, not a denial.
3270 */
3271 error = cap_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3272 SECURITY_CAP_NOAUDIT);
3273 if (!error)
3274 error = cred_has_capability(current_cred(), CAP_MAC_ADMIN,
3275 SECURITY_CAP_NOAUDIT, true);
3276 isec = inode_security(inode);
3277 if (!error)
3278 error = security_sid_to_context_force(isec->sid, &context,
3279 &size);
3280 else
3281 error = security_sid_to_context(isec->sid, &context, &size);
3282 if (error)
3283 return error;
3284 error = size;
3285 if (alloc) {
3286 *buffer = context;
3287 goto out_nofree;
3288 }
3289 kfree(context);
3290out_nofree:
3291 return error;
3292}
3293
3294static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3295 const void *value, size_t size, int flags)
3296{
3297 struct inode_security_struct *isec = inode_security_novalidate(inode);
3298 u32 newsid;
3299 int rc;
3300
3301 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3302 return -EOPNOTSUPP;
3303
3304 if (!value || !size)
3305 return -EACCES;
3306
3307 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3308 if (rc)
3309 return rc;
3310
3311 spin_lock(&isec->lock);
3312 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3313 isec->sid = newsid;
3314 isec->initialized = LABEL_INITIALIZED;
3315 spin_unlock(&isec->lock);
3316 return 0;
3317}
3318
3319static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3320{
3321 const int len = sizeof(XATTR_NAME_SELINUX);
3322 if (buffer && len <= buffer_size)
3323 memcpy(buffer, XATTR_NAME_SELINUX, len);
3324 return len;
3325}
3326
3327static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3328{
3329 struct inode_security_struct *isec = inode_security_novalidate(inode);
3330 *secid = isec->sid;
3331}
3332
3333static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3334{
3335 u32 sid;
3336 struct task_security_struct *tsec;
3337 struct cred *new_creds = *new;
3338
3339 if (new_creds == NULL) {
3340 new_creds = prepare_creds();
3341 if (!new_creds)
3342 return -ENOMEM;
3343 }
3344
3345 tsec = new_creds->security;
3346 /* Get label from overlay inode and set it in create_sid */
3347 selinux_inode_getsecid(d_inode(src), &sid);
3348 tsec->create_sid = sid;
3349 *new = new_creds;
3350 return 0;
3351}
3352
3353static int selinux_inode_copy_up_xattr(const char *name)
3354{
3355 /* The copy_up hook above sets the initial context on an inode, but we
3356 * don't then want to overwrite it by blindly copying all the lower
3357 * xattrs up. Instead, we have to filter out SELinux-related xattrs.
3358 */
3359 if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3360 return 1; /* Discard */
3361 /*
3362 * Any other attribute apart from SELINUX is not claimed, supported
3363 * by selinux.
3364 */
3365 return -EOPNOTSUPP;
3366}
3367
3368/* file security operations */
3369
3370static int selinux_revalidate_file_permission(struct file *file, int mask)
3371{
3372 const struct cred *cred = current_cred();
3373 struct inode *inode = file_inode(file);
3374
3375 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3376 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3377 mask |= MAY_APPEND;
3378
3379 return file_has_perm(cred, file,
3380 file_mask_to_av(inode->i_mode, mask));
3381}
3382
3383static int selinux_file_permission(struct file *file, int mask)
3384{
3385 struct inode *inode = file_inode(file);
3386 struct file_security_struct *fsec = file->f_security;
3387 struct inode_security_struct *isec;
3388 u32 sid = current_sid();
3389
3390 if (!mask)
3391 /* No permission to check. Existence test. */
3392 return 0;
3393
3394 isec = inode_security(inode);
3395 if (sid == fsec->sid && fsec->isid == isec->sid &&
3396 fsec->pseqno == avc_policy_seqno())
3397 /* No change since file_open check. */
3398 return 0;
3399
3400 return selinux_revalidate_file_permission(file, mask);
3401}
3402
3403static int selinux_file_alloc_security(struct file *file)
3404{
3405 return file_alloc_security(file);
3406}
3407
3408static void selinux_file_free_security(struct file *file)
3409{
3410 file_free_security(file);
3411}
3412
3413/*
3414 * Check whether a task has the ioctl permission and cmd
3415 * operation to an inode.
3416 */
3417static int ioctl_has_perm(const struct cred *cred, struct file *file,
3418 u32 requested, u16 cmd)
3419{
3420 struct common_audit_data ad;
3421 struct file_security_struct *fsec = file->f_security;
3422 struct inode *inode = file_inode(file);
3423 struct inode_security_struct *isec;
3424 struct lsm_ioctlop_audit ioctl;
3425 u32 ssid = cred_sid(cred);
3426 int rc;
3427 u8 driver = cmd >> 8;
3428 u8 xperm = cmd & 0xff;
3429
3430 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3431 ad.u.op = &ioctl;
3432 ad.u.op->cmd = cmd;
3433 ad.u.op->path = file->f_path;
3434
3435 if (ssid != fsec->sid) {
3436 rc = avc_has_perm(ssid, fsec->sid,
3437 SECCLASS_FD,
3438 FD__USE,
3439 &ad);
3440 if (rc)
3441 goto out;
3442 }
3443
3444 if (unlikely(IS_PRIVATE(inode)))
3445 return 0;
3446
3447 isec = inode_security(inode);
3448 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
3449 requested, driver, xperm, &ad);
3450out:
3451 return rc;
3452}
3453
3454static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3455 unsigned long arg)
3456{
3457 const struct cred *cred = current_cred();
3458 int error = 0;
3459
3460 switch (cmd) {
3461 case FIONREAD:
3462 /* fall through */
3463 case FIBMAP:
3464 /* fall through */
3465 case FIGETBSZ:
3466 /* fall through */
3467 case FS_IOC_GETFLAGS:
3468 /* fall through */
3469 case FS_IOC_GETVERSION:
3470 error = file_has_perm(cred, file, FILE__GETATTR);
3471 break;
3472
3473 case FS_IOC_SETFLAGS:
3474 /* fall through */
3475 case FS_IOC_SETVERSION:
3476 error = file_has_perm(cred, file, FILE__SETATTR);
3477 break;
3478
3479 /* sys_ioctl() checks */
3480 case FIONBIO:
3481 /* fall through */
3482 case FIOASYNC:
3483 error = file_has_perm(cred, file, 0);
3484 break;
3485
3486 case KDSKBENT:
3487 case KDSKBSENT:
3488 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3489 SECURITY_CAP_AUDIT, true);
3490 break;
3491
3492 /* default case assumes that the command will go
3493 * to the file's ioctl() function.
3494 */
3495 default:
3496 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3497 }
3498 return error;
3499}
3500
3501static int default_noexec;
3502
3503static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3504{
3505 const struct cred *cred = current_cred();
3506 int rc = 0;
3507
3508 if (default_noexec &&
3509 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3510 (!shared && (prot & PROT_WRITE)))) {
3511 /*
3512 * We are making executable an anonymous mapping or a
3513 * private file mapping that will also be writable.
3514 * This has an additional check.
3515 */
3516 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3517 if (rc)
3518 goto error;
3519 }
3520
3521 if (file) {
3522 /* read access is always possible with a mapping */
3523 u32 av = FILE__READ;
3524
3525 /* write access only matters if the mapping is shared */
3526 if (shared && (prot & PROT_WRITE))
3527 av |= FILE__WRITE;
3528
3529 if (prot & PROT_EXEC)
3530 av |= FILE__EXECUTE;
3531
3532 return file_has_perm(cred, file, av);
3533 }
3534
3535error:
3536 return rc;
3537}
3538
3539static int selinux_mmap_addr(unsigned long addr)
3540{
3541 int rc = 0;
3542
3543 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3544 u32 sid = current_sid();
3545 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3546 MEMPROTECT__MMAP_ZERO, NULL);
3547 }
3548
3549 return rc;
3550}
3551
3552static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3553 unsigned long prot, unsigned long flags)
3554{
3555 if (selinux_checkreqprot)
3556 prot = reqprot;
3557
3558 return file_map_prot_check(file, prot,
3559 (flags & MAP_TYPE) == MAP_SHARED);
3560}
3561
3562static int selinux_file_mprotect(struct vm_area_struct *vma,
3563 unsigned long reqprot,
3564 unsigned long prot)
3565{
3566 const struct cred *cred = current_cred();
3567
3568 if (selinux_checkreqprot)
3569 prot = reqprot;
3570
3571 if (default_noexec &&
3572 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3573 int rc = 0;
3574 if (vma->vm_start >= vma->vm_mm->start_brk &&
3575 vma->vm_end <= vma->vm_mm->brk) {
3576 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3577 } else if (!vma->vm_file &&
3578 ((vma->vm_start <= vma->vm_mm->start_stack &&
3579 vma->vm_end >= vma->vm_mm->start_stack) ||
3580 vma_is_stack_for_current(vma))) {
3581 rc = current_has_perm(current, PROCESS__EXECSTACK);
3582 } else if (vma->vm_file && vma->anon_vma) {
3583 /*
3584 * We are making executable a file mapping that has
3585 * had some COW done. Since pages might have been
3586 * written, check ability to execute the possibly
3587 * modified content. This typically should only
3588 * occur for text relocations.
3589 */
3590 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3591 }
3592 if (rc)
3593 return rc;
3594 }
3595
3596 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3597}
3598
3599static int selinux_file_lock(struct file *file, unsigned int cmd)
3600{
3601 const struct cred *cred = current_cred();
3602
3603 return file_has_perm(cred, file, FILE__LOCK);
3604}
3605
3606static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3607 unsigned long arg)
3608{
3609 const struct cred *cred = current_cred();
3610 int err = 0;
3611
3612 switch (cmd) {
3613 case F_SETFL:
3614 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3615 err = file_has_perm(cred, file, FILE__WRITE);
3616 break;
3617 }
3618 /* fall through */
3619 case F_SETOWN:
3620 case F_SETSIG:
3621 case F_GETFL:
3622 case F_GETOWN:
3623 case F_GETSIG:
3624 case F_GETOWNER_UIDS:
3625 /* Just check FD__USE permission */
3626 err = file_has_perm(cred, file, 0);
3627 break;
3628 case F_GETLK:
3629 case F_SETLK:
3630 case F_SETLKW:
3631 case F_OFD_GETLK:
3632 case F_OFD_SETLK:
3633 case F_OFD_SETLKW:
3634#if BITS_PER_LONG == 32
3635 case F_GETLK64:
3636 case F_SETLK64:
3637 case F_SETLKW64:
3638#endif
3639 err = file_has_perm(cred, file, FILE__LOCK);
3640 break;
3641 }
3642
3643 return err;
3644}
3645
3646static void selinux_file_set_fowner(struct file *file)
3647{
3648 struct file_security_struct *fsec;
3649
3650 fsec = file->f_security;
3651 fsec->fown_sid = current_sid();
3652}
3653
3654static int selinux_file_send_sigiotask(struct task_struct *tsk,
3655 struct fown_struct *fown, int signum)
3656{
3657 struct file *file;
3658 u32 sid = task_sid(tsk);
3659 u32 perm;
3660 struct file_security_struct *fsec;
3661
3662 /* struct fown_struct is never outside the context of a struct file */
3663 file = container_of(fown, struct file, f_owner);
3664
3665 fsec = file->f_security;
3666
3667 if (!signum)
3668 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3669 else
3670 perm = signal_to_av(signum);
3671
3672 return avc_has_perm(fsec->fown_sid, sid,
3673 SECCLASS_PROCESS, perm, NULL);
3674}
3675
3676static int selinux_file_receive(struct file *file)
3677{
3678 const struct cred *cred = current_cred();
3679
3680 return file_has_perm(cred, file, file_to_av(file));
3681}
3682
3683static int selinux_file_open(struct file *file, const struct cred *cred)
3684{
3685 struct file_security_struct *fsec;
3686 struct inode_security_struct *isec;
3687
3688 fsec = file->f_security;
3689 isec = inode_security(file_inode(file));
3690 /*
3691 * Save inode label and policy sequence number
3692 * at open-time so that selinux_file_permission
3693 * can determine whether revalidation is necessary.
3694 * Task label is already saved in the file security
3695 * struct as its SID.
3696 */
3697 fsec->isid = isec->sid;
3698 fsec->pseqno = avc_policy_seqno();
3699 /*
3700 * Since the inode label or policy seqno may have changed
3701 * between the selinux_inode_permission check and the saving
3702 * of state above, recheck that access is still permitted.
3703 * Otherwise, access might never be revalidated against the
3704 * new inode label or new policy.
3705 * This check is not redundant - do not remove.
3706 */
3707 return file_path_has_perm(cred, file, open_file_to_av(file));
3708}
3709
3710/* task security operations */
3711
3712static int selinux_task_create(unsigned long clone_flags)
3713{
3714 return current_has_perm(current, PROCESS__FORK);
3715}
3716
3717/*
3718 * allocate the SELinux part of blank credentials
3719 */
3720static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3721{
3722 struct task_security_struct *tsec;
3723
3724 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3725 if (!tsec)
3726 return -ENOMEM;
3727
3728 cred->security = tsec;
3729 return 0;
3730}
3731
3732/*
3733 * detach and free the LSM part of a set of credentials
3734 */
3735static void selinux_cred_free(struct cred *cred)
3736{
3737 struct task_security_struct *tsec = cred->security;
3738
3739 /*
3740 * cred->security == NULL if security_cred_alloc_blank() or
3741 * security_prepare_creds() returned an error.
3742 */
3743 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3744 cred->security = (void *) 0x7UL;
3745 kfree(tsec);
3746}
3747
3748/*
3749 * prepare a new set of credentials for modification
3750 */
3751static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3752 gfp_t gfp)
3753{
3754 const struct task_security_struct *old_tsec;
3755 struct task_security_struct *tsec;
3756
3757 old_tsec = old->security;
3758
3759 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3760 if (!tsec)
3761 return -ENOMEM;
3762
3763 new->security = tsec;
3764 return 0;
3765}
3766
3767/*
3768 * transfer the SELinux data to a blank set of creds
3769 */
3770static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3771{
3772 const struct task_security_struct *old_tsec = old->security;
3773 struct task_security_struct *tsec = new->security;
3774
3775 *tsec = *old_tsec;
3776}
3777
3778/*
3779 * set the security data for a kernel service
3780 * - all the creation contexts are set to unlabelled
3781 */
3782static int selinux_kernel_act_as(struct cred *new, u32 secid)
3783{
3784 struct task_security_struct *tsec = new->security;
3785 u32 sid = current_sid();
3786 int ret;
3787
3788 ret = avc_has_perm(sid, secid,
3789 SECCLASS_KERNEL_SERVICE,
3790 KERNEL_SERVICE__USE_AS_OVERRIDE,
3791 NULL);
3792 if (ret == 0) {
3793 tsec->sid = secid;
3794 tsec->create_sid = 0;
3795 tsec->keycreate_sid = 0;
3796 tsec->sockcreate_sid = 0;
3797 }
3798 return ret;
3799}
3800
3801/*
3802 * set the file creation context in a security record to the same as the
3803 * objective context of the specified inode
3804 */
3805static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3806{
3807 struct inode_security_struct *isec = inode_security(inode);
3808 struct task_security_struct *tsec = new->security;
3809 u32 sid = current_sid();
3810 int ret;
3811
3812 ret = avc_has_perm(sid, isec->sid,
3813 SECCLASS_KERNEL_SERVICE,
3814 KERNEL_SERVICE__CREATE_FILES_AS,
3815 NULL);
3816
3817 if (ret == 0)
3818 tsec->create_sid = isec->sid;
3819 return ret;
3820}
3821
3822static int selinux_kernel_module_request(char *kmod_name)
3823{
3824 u32 sid;
3825 struct common_audit_data ad;
3826
3827 sid = task_sid(current);
3828
3829 ad.type = LSM_AUDIT_DATA_KMOD;
3830 ad.u.kmod_name = kmod_name;
3831
3832 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3833 SYSTEM__MODULE_REQUEST, &ad);
3834}
3835
3836static int selinux_kernel_module_from_file(struct file *file)
3837{
3838 struct common_audit_data ad;
3839 struct inode_security_struct *isec;
3840 struct file_security_struct *fsec;
3841 u32 sid = current_sid();
3842 int rc;
3843
3844 /* init_module */
3845 if (file == NULL)
3846 return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
3847 SYSTEM__MODULE_LOAD, NULL);
3848
3849 /* finit_module */
3850
3851 ad.type = LSM_AUDIT_DATA_FILE;
3852 ad.u.file = file;
3853
3854 fsec = file->f_security;
3855 if (sid != fsec->sid) {
3856 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
3857 if (rc)
3858 return rc;
3859 }
3860
3861 isec = inode_security(file_inode(file));
3862 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
3863 SYSTEM__MODULE_LOAD, &ad);
3864}
3865
3866static int selinux_kernel_read_file(struct file *file,
3867 enum kernel_read_file_id id)
3868{
3869 int rc = 0;
3870
3871 switch (id) {
3872 case READING_MODULE:
3873 rc = selinux_kernel_module_from_file(file);
3874 break;
3875 default:
3876 break;
3877 }
3878
3879 return rc;
3880}
3881
3882static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3883{
3884 return current_has_perm(p, PROCESS__SETPGID);
3885}
3886
3887static int selinux_task_getpgid(struct task_struct *p)
3888{
3889 return current_has_perm(p, PROCESS__GETPGID);
3890}
3891
3892static int selinux_task_getsid(struct task_struct *p)
3893{
3894 return current_has_perm(p, PROCESS__GETSESSION);
3895}
3896
3897static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3898{
3899 *secid = task_sid(p);
3900}
3901
3902static int selinux_task_setnice(struct task_struct *p, int nice)
3903{
3904 return current_has_perm(p, PROCESS__SETSCHED);
3905}
3906
3907static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3908{
3909 return current_has_perm(p, PROCESS__SETSCHED);
3910}
3911
3912static int selinux_task_getioprio(struct task_struct *p)
3913{
3914 return current_has_perm(p, PROCESS__GETSCHED);
3915}
3916
3917static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3918 struct rlimit *new_rlim)
3919{
3920 struct rlimit *old_rlim = p->signal->rlim + resource;
3921
3922 /* Control the ability to change the hard limit (whether
3923 lowering or raising it), so that the hard limit can
3924 later be used as a safe reset point for the soft limit
3925 upon context transitions. See selinux_bprm_committing_creds. */
3926 if (old_rlim->rlim_max != new_rlim->rlim_max)
3927 return current_has_perm(p, PROCESS__SETRLIMIT);
3928
3929 return 0;
3930}
3931
3932static int selinux_task_setscheduler(struct task_struct *p)
3933{
3934 return current_has_perm(p, PROCESS__SETSCHED);
3935}
3936
3937static int selinux_task_getscheduler(struct task_struct *p)
3938{
3939 return current_has_perm(p, PROCESS__GETSCHED);
3940}
3941
3942static int selinux_task_movememory(struct task_struct *p)
3943{
3944 return current_has_perm(p, PROCESS__SETSCHED);
3945}
3946
3947static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3948 int sig, u32 secid)
3949{
3950 u32 perm;
3951 int rc;
3952
3953 if (!sig)
3954 perm = PROCESS__SIGNULL; /* null signal; existence test */
3955 else
3956 perm = signal_to_av(sig);
3957 if (secid)
3958 rc = avc_has_perm(secid, task_sid(p),
3959 SECCLASS_PROCESS, perm, NULL);
3960 else
3961 rc = current_has_perm(p, perm);
3962 return rc;
3963}
3964
3965static int selinux_task_wait(struct task_struct *p)
3966{
3967 return task_has_perm(p, current, PROCESS__SIGCHLD);
3968}
3969
3970static void selinux_task_to_inode(struct task_struct *p,
3971 struct inode *inode)
3972{
3973 struct inode_security_struct *isec = inode->i_security;
3974 u32 sid = task_sid(p);
3975
3976 spin_lock(&isec->lock);
3977 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3978 isec->sid = sid;
3979 isec->initialized = LABEL_INITIALIZED;
3980 spin_unlock(&isec->lock);
3981}
3982
3983/* Returns error only if unable to parse addresses */
3984static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3985 struct common_audit_data *ad, u8 *proto)
3986{
3987 int offset, ihlen, ret = -EINVAL;
3988 struct iphdr _iph, *ih;
3989
3990 offset = skb_network_offset(skb);
3991 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3992 if (ih == NULL)
3993 goto out;
3994
3995 ihlen = ih->ihl * 4;
3996 if (ihlen < sizeof(_iph))
3997 goto out;
3998
3999 ad->u.net->v4info.saddr = ih->saddr;
4000 ad->u.net->v4info.daddr = ih->daddr;
4001 ret = 0;
4002
4003 if (proto)
4004 *proto = ih->protocol;
4005
4006 switch (ih->protocol) {
4007 case IPPROTO_TCP: {
4008 struct tcphdr _tcph, *th;
4009
4010 if (ntohs(ih->frag_off) & IP_OFFSET)
4011 break;
4012
4013 offset += ihlen;
4014 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4015 if (th == NULL)
4016 break;
4017
4018 ad->u.net->sport = th->source;
4019 ad->u.net->dport = th->dest;
4020 break;
4021 }
4022
4023 case IPPROTO_UDP: {
4024 struct udphdr _udph, *uh;
4025
4026 if (ntohs(ih->frag_off) & IP_OFFSET)
4027 break;
4028
4029 offset += ihlen;
4030 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4031 if (uh == NULL)
4032 break;
4033
4034 ad->u.net->sport = uh->source;
4035 ad->u.net->dport = uh->dest;
4036 break;
4037 }
4038
4039 case IPPROTO_DCCP: {
4040 struct dccp_hdr _dccph, *dh;
4041
4042 if (ntohs(ih->frag_off) & IP_OFFSET)
4043 break;
4044
4045 offset += ihlen;
4046 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4047 if (dh == NULL)
4048 break;
4049
4050 ad->u.net->sport = dh->dccph_sport;
4051 ad->u.net->dport = dh->dccph_dport;
4052 break;
4053 }
4054
4055 default:
4056 break;
4057 }
4058out:
4059 return ret;
4060}
4061
4062#if IS_ENABLED(CONFIG_IPV6)
4063
4064/* Returns error only if unable to parse addresses */
4065static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4066 struct common_audit_data *ad, u8 *proto)
4067{
4068 u8 nexthdr;
4069 int ret = -EINVAL, offset;
4070 struct ipv6hdr _ipv6h, *ip6;
4071 __be16 frag_off;
4072
4073 offset = skb_network_offset(skb);
4074 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4075 if (ip6 == NULL)
4076 goto out;
4077
4078 ad->u.net->v6info.saddr = ip6->saddr;
4079 ad->u.net->v6info.daddr = ip6->daddr;
4080 ret = 0;
4081
4082 nexthdr = ip6->nexthdr;
4083 offset += sizeof(_ipv6h);
4084 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4085 if (offset < 0)
4086 goto out;
4087
4088 if (proto)
4089 *proto = nexthdr;
4090
4091 switch (nexthdr) {
4092 case IPPROTO_TCP: {
4093 struct tcphdr _tcph, *th;
4094
4095 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4096 if (th == NULL)
4097 break;
4098
4099 ad->u.net->sport = th->source;
4100 ad->u.net->dport = th->dest;
4101 break;
4102 }
4103
4104 case IPPROTO_UDP: {
4105 struct udphdr _udph, *uh;
4106
4107 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4108 if (uh == NULL)
4109 break;
4110
4111 ad->u.net->sport = uh->source;
4112 ad->u.net->dport = uh->dest;
4113 break;
4114 }
4115
4116 case IPPROTO_DCCP: {
4117 struct dccp_hdr _dccph, *dh;
4118
4119 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4120 if (dh == NULL)
4121 break;
4122
4123 ad->u.net->sport = dh->dccph_sport;
4124 ad->u.net->dport = dh->dccph_dport;
4125 break;
4126 }
4127
4128 /* includes fragments */
4129 default:
4130 break;
4131 }
4132out:
4133 return ret;
4134}
4135
4136#endif /* IPV6 */
4137
4138static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4139 char **_addrp, int src, u8 *proto)
4140{
4141 char *addrp;
4142 int ret;
4143
4144 switch (ad->u.net->family) {
4145 case PF_INET:
4146 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4147 if (ret)
4148 goto parse_error;
4149 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4150 &ad->u.net->v4info.daddr);
4151 goto okay;
4152
4153#if IS_ENABLED(CONFIG_IPV6)
4154 case PF_INET6:
4155 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4156 if (ret)
4157 goto parse_error;
4158 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4159 &ad->u.net->v6info.daddr);
4160 goto okay;
4161#endif /* IPV6 */
4162 default:
4163 addrp = NULL;
4164 goto okay;
4165 }
4166
4167parse_error:
4168 printk(KERN_WARNING
4169 "SELinux: failure in selinux_parse_skb(),"
4170 " unable to parse packet\n");
4171 return ret;
4172
4173okay:
4174 if (_addrp)
4175 *_addrp = addrp;
4176 return 0;
4177}
4178
4179/**
4180 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4181 * @skb: the packet
4182 * @family: protocol family
4183 * @sid: the packet's peer label SID
4184 *
4185 * Description:
4186 * Check the various different forms of network peer labeling and determine
4187 * the peer label/SID for the packet; most of the magic actually occurs in
4188 * the security server function security_net_peersid_cmp(). The function
4189 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4190 * or -EACCES if @sid is invalid due to inconsistencies with the different
4191 * peer labels.
4192 *
4193 */
4194static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4195{
4196 int err;
4197 u32 xfrm_sid;
4198 u32 nlbl_sid;
4199 u32 nlbl_type;
4200
4201 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4202 if (unlikely(err))
4203 return -EACCES;
4204 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4205 if (unlikely(err))
4206 return -EACCES;
4207
4208 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
4209 if (unlikely(err)) {
4210 printk(KERN_WARNING
4211 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4212 " unable to determine packet's peer label\n");
4213 return -EACCES;
4214 }
4215
4216 return 0;
4217}
4218
4219/**
4220 * selinux_conn_sid - Determine the child socket label for a connection
4221 * @sk_sid: the parent socket's SID
4222 * @skb_sid: the packet's SID
4223 * @conn_sid: the resulting connection SID
4224 *
4225 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4226 * combined with the MLS information from @skb_sid in order to create
4227 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy
4228 * of @sk_sid. Returns zero on success, negative values on failure.
4229 *
4230 */
4231static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4232{
4233 int err = 0;
4234
4235 if (skb_sid != SECSID_NULL)
4236 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
4237 else
4238 *conn_sid = sk_sid;
4239
4240 return err;
4241}
4242
4243/* socket security operations */
4244
4245static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4246 u16 secclass, u32 *socksid)
4247{
4248 if (tsec->sockcreate_sid > SECSID_NULL) {
4249 *socksid = tsec->sockcreate_sid;
4250 return 0;
4251 }
4252
4253 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
4254 socksid);
4255}
4256
4257static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
4258{
4259 struct sk_security_struct *sksec = sk->sk_security;
4260 struct common_audit_data ad;
4261 struct lsm_network_audit net = {0,};
4262 u32 tsid = task_sid(task);
4263
4264 if (sksec->sid == SECINITSID_KERNEL)
4265 return 0;
4266
4267 ad.type = LSM_AUDIT_DATA_NET;
4268 ad.u.net = &net;
4269 ad.u.net->sk = sk;
4270
4271 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
4272}
4273
4274static int selinux_socket_create(int family, int type,
4275 int protocol, int kern)
4276{
4277 const struct task_security_struct *tsec = current_security();
4278 u32 newsid;
4279 u16 secclass;
4280 int rc;
4281
4282 if (kern)
4283 return 0;
4284
4285 secclass = socket_type_to_security_class(family, type, protocol);
4286 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4287 if (rc)
4288 return rc;
4289
4290 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4291}
4292
4293static int selinux_socket_post_create(struct socket *sock, int family,
4294 int type, int protocol, int kern)
4295{
4296 const struct task_security_struct *tsec = current_security();
4297 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4298 struct sk_security_struct *sksec;
4299 u16 sclass = socket_type_to_security_class(family, type, protocol);
4300 u32 sid = SECINITSID_KERNEL;
4301 int err = 0;
4302
4303 if (!kern) {
4304 err = socket_sockcreate_sid(tsec, sclass, &sid);
4305 if (err)
4306 return err;
4307 }
4308
4309 isec->sclass = sclass;
4310 isec->sid = sid;
4311 isec->initialized = LABEL_INITIALIZED;
4312
4313 if (sock->sk) {
4314 sksec = sock->sk->sk_security;
4315 sksec->sclass = sclass;
4316 sksec->sid = sid;
4317 err = selinux_netlbl_socket_post_create(sock->sk, family);
4318 }
4319
4320 return err;
4321}
4322
4323/* Range of port numbers used to automatically bind.
4324 Need to determine whether we should perform a name_bind
4325 permission check between the socket and the port number. */
4326
4327static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4328{
4329 struct sock *sk = sock->sk;
4330 u16 family;
4331 int err;
4332
4333 err = sock_has_perm(current, sk, SOCKET__BIND);
4334 if (err)
4335 goto out;
4336
4337 /*
4338 * If PF_INET or PF_INET6, check name_bind permission for the port.
4339 * Multiple address binding for SCTP is not supported yet: we just
4340 * check the first address now.
4341 */
4342 family = sk->sk_family;
4343 if (family == PF_INET || family == PF_INET6) {
4344 char *addrp;
4345 struct sk_security_struct *sksec = sk->sk_security;
4346 struct common_audit_data ad;
4347 struct lsm_network_audit net = {0,};
4348 struct sockaddr_in *addr4 = NULL;
4349 struct sockaddr_in6 *addr6 = NULL;
4350 unsigned short snum;
4351 u32 sid, node_perm;
4352
4353 if (family == PF_INET) {
4354 addr4 = (struct sockaddr_in *)address;
4355 snum = ntohs(addr4->sin_port);
4356 addrp = (char *)&addr4->sin_addr.s_addr;
4357 } else {
4358 addr6 = (struct sockaddr_in6 *)address;
4359 snum = ntohs(addr6->sin6_port);
4360 addrp = (char *)&addr6->sin6_addr.s6_addr;
4361 }
4362
4363 if (snum) {
4364 int low, high;
4365
4366 inet_get_local_port_range(sock_net(sk), &low, &high);
4367
4368 if (snum < max(PROT_SOCK, low) || snum > high) {
4369 err = sel_netport_sid(sk->sk_protocol,
4370 snum, &sid);
4371 if (err)
4372 goto out;
4373 ad.type = LSM_AUDIT_DATA_NET;
4374 ad.u.net = &net;
4375 ad.u.net->sport = htons(snum);
4376 ad.u.net->family = family;
4377 err = avc_has_perm(sksec->sid, sid,
4378 sksec->sclass,
4379 SOCKET__NAME_BIND, &ad);
4380 if (err)
4381 goto out;
4382 }
4383 }
4384
4385 switch (sksec->sclass) {
4386 case SECCLASS_TCP_SOCKET:
4387 node_perm = TCP_SOCKET__NODE_BIND;
4388 break;
4389
4390 case SECCLASS_UDP_SOCKET:
4391 node_perm = UDP_SOCKET__NODE_BIND;
4392 break;
4393
4394 case SECCLASS_DCCP_SOCKET:
4395 node_perm = DCCP_SOCKET__NODE_BIND;
4396 break;
4397
4398 default:
4399 node_perm = RAWIP_SOCKET__NODE_BIND;
4400 break;
4401 }
4402
4403 err = sel_netnode_sid(addrp, family, &sid);
4404 if (err)
4405 goto out;
4406
4407 ad.type = LSM_AUDIT_DATA_NET;
4408 ad.u.net = &net;
4409 ad.u.net->sport = htons(snum);
4410 ad.u.net->family = family;
4411
4412 if (family == PF_INET)
4413 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4414 else
4415 ad.u.net->v6info.saddr = addr6->sin6_addr;
4416
4417 err = avc_has_perm(sksec->sid, sid,
4418 sksec->sclass, node_perm, &ad);
4419 if (err)
4420 goto out;
4421 }
4422out:
4423 return err;
4424}
4425
4426static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4427{
4428 struct sock *sk = sock->sk;
4429 struct sk_security_struct *sksec = sk->sk_security;
4430 int err;
4431
4432 err = sock_has_perm(current, sk, SOCKET__CONNECT);
4433 if (err)
4434 return err;
4435
4436 /*
4437 * If a TCP or DCCP socket, check name_connect permission for the port.
4438 */
4439 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4440 sksec->sclass == SECCLASS_DCCP_SOCKET) {
4441 struct common_audit_data ad;
4442 struct lsm_network_audit net = {0,};
4443 struct sockaddr_in *addr4 = NULL;
4444 struct sockaddr_in6 *addr6 = NULL;
4445 unsigned short snum;
4446 u32 sid, perm;
4447
4448 if (sk->sk_family == PF_INET) {
4449 addr4 = (struct sockaddr_in *)address;
4450 if (addrlen < sizeof(struct sockaddr_in))
4451 return -EINVAL;
4452 snum = ntohs(addr4->sin_port);
4453 } else {
4454 addr6 = (struct sockaddr_in6 *)address;
4455 if (addrlen < SIN6_LEN_RFC2133)
4456 return -EINVAL;
4457 snum = ntohs(addr6->sin6_port);
4458 }
4459
4460 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4461 if (err)
4462 goto out;
4463
4464 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4465 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4466
4467 ad.type = LSM_AUDIT_DATA_NET;
4468 ad.u.net = &net;
4469 ad.u.net->dport = htons(snum);
4470 ad.u.net->family = sk->sk_family;
4471 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4472 if (err)
4473 goto out;
4474 }
4475
4476 err = selinux_netlbl_socket_connect(sk, address);
4477
4478out:
4479 return err;
4480}
4481
4482static int selinux_socket_listen(struct socket *sock, int backlog)
4483{
4484 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4485}
4486
4487static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4488{
4489 int err;
4490 struct inode_security_struct *isec;
4491 struct inode_security_struct *newisec;
4492 u16 sclass;
4493 u32 sid;
4494
4495 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4496 if (err)
4497 return err;
4498
4499 isec = inode_security_novalidate(SOCK_INODE(sock));
4500 spin_lock(&isec->lock);
4501 sclass = isec->sclass;
4502 sid = isec->sid;
4503 spin_unlock(&isec->lock);
4504
4505 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4506 newisec->sclass = sclass;
4507 newisec->sid = sid;
4508 newisec->initialized = LABEL_INITIALIZED;
4509
4510 return 0;
4511}
4512
4513static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4514 int size)
4515{
4516 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4517}
4518
4519static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4520 int size, int flags)
4521{
4522 return sock_has_perm(current, sock->sk, SOCKET__READ);
4523}
4524
4525static int selinux_socket_getsockname(struct socket *sock)
4526{
4527 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4528}
4529
4530static int selinux_socket_getpeername(struct socket *sock)
4531{
4532 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4533}
4534
4535static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4536{
4537 int err;
4538
4539 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4540 if (err)
4541 return err;
4542
4543 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4544}
4545
4546static int selinux_socket_getsockopt(struct socket *sock, int level,
4547 int optname)
4548{
4549 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4550}
4551
4552static int selinux_socket_shutdown(struct socket *sock, int how)
4553{
4554 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4555}
4556
4557static int selinux_socket_unix_stream_connect(struct sock *sock,
4558 struct sock *other,
4559 struct sock *newsk)
4560{
4561 struct sk_security_struct *sksec_sock = sock->sk_security;
4562 struct sk_security_struct *sksec_other = other->sk_security;
4563 struct sk_security_struct *sksec_new = newsk->sk_security;
4564 struct common_audit_data ad;
4565 struct lsm_network_audit net = {0,};
4566 int err;
4567
4568 ad.type = LSM_AUDIT_DATA_NET;
4569 ad.u.net = &net;
4570 ad.u.net->sk = other;
4571
4572 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4573 sksec_other->sclass,
4574 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4575 if (err)
4576 return err;
4577
4578 /* server child socket */
4579 sksec_new->peer_sid = sksec_sock->sid;
4580 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4581 &sksec_new->sid);
4582 if (err)
4583 return err;
4584
4585 /* connecting socket */
4586 sksec_sock->peer_sid = sksec_new->sid;
4587
4588 return 0;
4589}
4590
4591static int selinux_socket_unix_may_send(struct socket *sock,
4592 struct socket *other)
4593{
4594 struct sk_security_struct *ssec = sock->sk->sk_security;
4595 struct sk_security_struct *osec = other->sk->sk_security;
4596 struct common_audit_data ad;
4597 struct lsm_network_audit net = {0,};
4598
4599 ad.type = LSM_AUDIT_DATA_NET;
4600 ad.u.net = &net;
4601 ad.u.net->sk = other->sk;
4602
4603 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4604 &ad);
4605}
4606
4607static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4608 char *addrp, u16 family, u32 peer_sid,
4609 struct common_audit_data *ad)
4610{
4611 int err;
4612 u32 if_sid;
4613 u32 node_sid;
4614
4615 err = sel_netif_sid(ns, ifindex, &if_sid);
4616 if (err)
4617 return err;
4618 err = avc_has_perm(peer_sid, if_sid,
4619 SECCLASS_NETIF, NETIF__INGRESS, ad);
4620 if (err)
4621 return err;
4622
4623 err = sel_netnode_sid(addrp, family, &node_sid);
4624 if (err)
4625 return err;
4626 return avc_has_perm(peer_sid, node_sid,
4627 SECCLASS_NODE, NODE__RECVFROM, ad);
4628}
4629
4630static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4631 u16 family)
4632{
4633 int err = 0;
4634 struct sk_security_struct *sksec = sk->sk_security;
4635 u32 sk_sid = sksec->sid;
4636 struct common_audit_data ad;
4637 struct lsm_network_audit net = {0,};
4638 char *addrp;
4639
4640 ad.type = LSM_AUDIT_DATA_NET;
4641 ad.u.net = &net;
4642 ad.u.net->netif = skb->skb_iif;
4643 ad.u.net->family = family;
4644 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4645 if (err)
4646 return err;
4647
4648 if (selinux_secmark_enabled()) {
4649 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4650 PACKET__RECV, &ad);
4651 if (err)
4652 return err;
4653 }
4654
4655 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4656 if (err)
4657 return err;
4658 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4659
4660 return err;
4661}
4662
4663static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4664{
4665 int err;
4666 struct sk_security_struct *sksec = sk->sk_security;
4667 u16 family = sk->sk_family;
4668 u32 sk_sid = sksec->sid;
4669 struct common_audit_data ad;
4670 struct lsm_network_audit net = {0,};
4671 char *addrp;
4672 u8 secmark_active;
4673 u8 peerlbl_active;
4674
4675 if (family != PF_INET && family != PF_INET6)
4676 return 0;
4677
4678 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4679 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4680 family = PF_INET;
4681
4682 /* If any sort of compatibility mode is enabled then handoff processing
4683 * to the selinux_sock_rcv_skb_compat() function to deal with the
4684 * special handling. We do this in an attempt to keep this function
4685 * as fast and as clean as possible. */
4686 if (!selinux_policycap_netpeer)
4687 return selinux_sock_rcv_skb_compat(sk, skb, family);
4688
4689 secmark_active = selinux_secmark_enabled();
4690 peerlbl_active = selinux_peerlbl_enabled();
4691 if (!secmark_active && !peerlbl_active)
4692 return 0;
4693
4694 ad.type = LSM_AUDIT_DATA_NET;
4695 ad.u.net = &net;
4696 ad.u.net->netif = skb->skb_iif;
4697 ad.u.net->family = family;
4698 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4699 if (err)
4700 return err;
4701
4702 if (peerlbl_active) {
4703 u32 peer_sid;
4704
4705 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4706 if (err)
4707 return err;
4708 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
4709 addrp, family, peer_sid, &ad);
4710 if (err) {
4711 selinux_netlbl_err(skb, family, err, 0);
4712 return err;
4713 }
4714 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4715 PEER__RECV, &ad);
4716 if (err) {
4717 selinux_netlbl_err(skb, family, err, 0);
4718 return err;
4719 }
4720 }
4721
4722 if (secmark_active) {
4723 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4724 PACKET__RECV, &ad);
4725 if (err)
4726 return err;
4727 }
4728
4729 return err;
4730}
4731
4732static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4733 int __user *optlen, unsigned len)
4734{
4735 int err = 0;
4736 char *scontext;
4737 u32 scontext_len;
4738 struct sk_security_struct *sksec = sock->sk->sk_security;
4739 u32 peer_sid = SECSID_NULL;
4740
4741 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4742 sksec->sclass == SECCLASS_TCP_SOCKET)
4743 peer_sid = sksec->peer_sid;
4744 if (peer_sid == SECSID_NULL)
4745 return -ENOPROTOOPT;
4746
4747 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4748 if (err)
4749 return err;
4750
4751 if (scontext_len > len) {
4752 err = -ERANGE;
4753 goto out_len;
4754 }
4755
4756 if (copy_to_user(optval, scontext, scontext_len))
4757 err = -EFAULT;
4758
4759out_len:
4760 if (put_user(scontext_len, optlen))
4761 err = -EFAULT;
4762 kfree(scontext);
4763 return err;
4764}
4765
4766static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4767{
4768 u32 peer_secid = SECSID_NULL;
4769 u16 family;
4770 struct inode_security_struct *isec;
4771
4772 if (skb && skb->protocol == htons(ETH_P_IP))
4773 family = PF_INET;
4774 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4775 family = PF_INET6;
4776 else if (sock)
4777 family = sock->sk->sk_family;
4778 else
4779 goto out;
4780
4781 if (sock && family == PF_UNIX) {
4782 isec = inode_security_novalidate(SOCK_INODE(sock));
4783 peer_secid = isec->sid;
4784 } else if (skb)
4785 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4786
4787out:
4788 *secid = peer_secid;
4789 if (peer_secid == SECSID_NULL)
4790 return -EINVAL;
4791 return 0;
4792}
4793
4794static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4795{
4796 struct sk_security_struct *sksec;
4797
4798 sksec = kzalloc(sizeof(*sksec), priority);
4799 if (!sksec)
4800 return -ENOMEM;
4801
4802 sksec->peer_sid = SECINITSID_UNLABELED;
4803 sksec->sid = SECINITSID_UNLABELED;
4804 sksec->sclass = SECCLASS_SOCKET;
4805 selinux_netlbl_sk_security_reset(sksec);
4806 sk->sk_security = sksec;
4807
4808 return 0;
4809}
4810
4811static void selinux_sk_free_security(struct sock *sk)
4812{
4813 struct sk_security_struct *sksec = sk->sk_security;
4814
4815 sk->sk_security = NULL;
4816 selinux_netlbl_sk_security_free(sksec);
4817 kfree(sksec);
4818}
4819
4820static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4821{
4822 struct sk_security_struct *sksec = sk->sk_security;
4823 struct sk_security_struct *newsksec = newsk->sk_security;
4824
4825 newsksec->sid = sksec->sid;
4826 newsksec->peer_sid = sksec->peer_sid;
4827 newsksec->sclass = sksec->sclass;
4828
4829 selinux_netlbl_sk_security_reset(newsksec);
4830}
4831
4832static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4833{
4834 if (!sk)
4835 *secid = SECINITSID_ANY_SOCKET;
4836 else {
4837 struct sk_security_struct *sksec = sk->sk_security;
4838
4839 *secid = sksec->sid;
4840 }
4841}
4842
4843static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4844{
4845 struct inode_security_struct *isec =
4846 inode_security_novalidate(SOCK_INODE(parent));
4847 struct sk_security_struct *sksec = sk->sk_security;
4848
4849 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4850 sk->sk_family == PF_UNIX)
4851 isec->sid = sksec->sid;
4852 sksec->sclass = isec->sclass;
4853}
4854
4855static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4856 struct request_sock *req)
4857{
4858 struct sk_security_struct *sksec = sk->sk_security;
4859 int err;
4860 u16 family = req->rsk_ops->family;
4861 u32 connsid;
4862 u32 peersid;
4863
4864 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4865 if (err)
4866 return err;
4867 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
4868 if (err)
4869 return err;
4870 req->secid = connsid;
4871 req->peer_secid = peersid;
4872
4873 return selinux_netlbl_inet_conn_request(req, family);
4874}
4875
4876static void selinux_inet_csk_clone(struct sock *newsk,
4877 const struct request_sock *req)
4878{
4879 struct sk_security_struct *newsksec = newsk->sk_security;
4880
4881 newsksec->sid = req->secid;
4882 newsksec->peer_sid = req->peer_secid;
4883 /* NOTE: Ideally, we should also get the isec->sid for the
4884 new socket in sync, but we don't have the isec available yet.
4885 So we will wait until sock_graft to do it, by which
4886 time it will have been created and available. */
4887
4888 /* We don't need to take any sort of lock here as we are the only
4889 * thread with access to newsksec */
4890 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4891}
4892
4893static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4894{
4895 u16 family = sk->sk_family;
4896 struct sk_security_struct *sksec = sk->sk_security;
4897
4898 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4899 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4900 family = PF_INET;
4901
4902 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4903}
4904
4905static int selinux_secmark_relabel_packet(u32 sid)
4906{
4907 const struct task_security_struct *__tsec;
4908 u32 tsid;
4909
4910 __tsec = current_security();
4911 tsid = __tsec->sid;
4912
4913 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4914}
4915
4916static void selinux_secmark_refcount_inc(void)
4917{
4918 atomic_inc(&selinux_secmark_refcount);
4919}
4920
4921static void selinux_secmark_refcount_dec(void)
4922{
4923 atomic_dec(&selinux_secmark_refcount);
4924}
4925
4926static void selinux_req_classify_flow(const struct request_sock *req,
4927 struct flowi *fl)
4928{
4929 fl->flowi_secid = req->secid;
4930}
4931
4932static int selinux_tun_dev_alloc_security(void **security)
4933{
4934 struct tun_security_struct *tunsec;
4935
4936 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4937 if (!tunsec)
4938 return -ENOMEM;
4939 tunsec->sid = current_sid();
4940
4941 *security = tunsec;
4942 return 0;
4943}
4944
4945static void selinux_tun_dev_free_security(void *security)
4946{
4947 kfree(security);
4948}
4949
4950static int selinux_tun_dev_create(void)
4951{
4952 u32 sid = current_sid();
4953
4954 /* we aren't taking into account the "sockcreate" SID since the socket
4955 * that is being created here is not a socket in the traditional sense,
4956 * instead it is a private sock, accessible only to the kernel, and
4957 * representing a wide range of network traffic spanning multiple
4958 * connections unlike traditional sockets - check the TUN driver to
4959 * get a better understanding of why this socket is special */
4960
4961 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4962 NULL);
4963}
4964
4965static int selinux_tun_dev_attach_queue(void *security)
4966{
4967 struct tun_security_struct *tunsec = security;
4968
4969 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4970 TUN_SOCKET__ATTACH_QUEUE, NULL);
4971}
4972
4973static int selinux_tun_dev_attach(struct sock *sk, void *security)
4974{
4975 struct tun_security_struct *tunsec = security;
4976 struct sk_security_struct *sksec = sk->sk_security;
4977
4978 /* we don't currently perform any NetLabel based labeling here and it
4979 * isn't clear that we would want to do so anyway; while we could apply
4980 * labeling without the support of the TUN user the resulting labeled
4981 * traffic from the other end of the connection would almost certainly
4982 * cause confusion to the TUN user that had no idea network labeling
4983 * protocols were being used */
4984
4985 sksec->sid = tunsec->sid;
4986 sksec->sclass = SECCLASS_TUN_SOCKET;
4987
4988 return 0;
4989}
4990
4991static int selinux_tun_dev_open(void *security)
4992{
4993 struct tun_security_struct *tunsec = security;
4994 u32 sid = current_sid();
4995 int err;
4996
4997 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4998 TUN_SOCKET__RELABELFROM, NULL);
4999 if (err)
5000 return err;
5001 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5002 TUN_SOCKET__RELABELTO, NULL);
5003 if (err)
5004 return err;
5005 tunsec->sid = sid;
5006
5007 return 0;
5008}
5009
5010static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
5011{
5012 int err = 0;
5013 u32 perm;
5014 struct nlmsghdr *nlh;
5015 struct sk_security_struct *sksec = sk->sk_security;
5016
5017 if (skb->len < NLMSG_HDRLEN) {
5018 err = -EINVAL;
5019 goto out;
5020 }
5021 nlh = nlmsg_hdr(skb);
5022
5023 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
5024 if (err) {
5025 if (err == -EINVAL) {
5026 pr_warn_ratelimited("SELinux: unrecognized netlink"
5027 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5028 " pig=%d comm=%s\n",
5029 sk->sk_protocol, nlh->nlmsg_type,
5030 secclass_map[sksec->sclass - 1].name,
5031 task_pid_nr(current), current->comm);
5032 if (!selinux_enforcing || security_get_allow_unknown())
5033 err = 0;
5034 }
5035
5036 /* Ignore */
5037 if (err == -ENOENT)
5038 err = 0;
5039 goto out;
5040 }
5041
5042 err = sock_has_perm(current, sk, perm);
5043out:
5044 return err;
5045}
5046
5047#ifdef CONFIG_NETFILTER
5048
5049static unsigned int selinux_ip_forward(struct sk_buff *skb,
5050 const struct net_device *indev,
5051 u16 family)
5052{
5053 int err;
5054 char *addrp;
5055 u32 peer_sid;
5056 struct common_audit_data ad;
5057 struct lsm_network_audit net = {0,};
5058 u8 secmark_active;
5059 u8 netlbl_active;
5060 u8 peerlbl_active;
5061
5062 if (!selinux_policycap_netpeer)
5063 return NF_ACCEPT;
5064
5065 secmark_active = selinux_secmark_enabled();
5066 netlbl_active = netlbl_enabled();
5067 peerlbl_active = selinux_peerlbl_enabled();
5068 if (!secmark_active && !peerlbl_active)
5069 return NF_ACCEPT;
5070
5071 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5072 return NF_DROP;
5073
5074 ad.type = LSM_AUDIT_DATA_NET;
5075 ad.u.net = &net;
5076 ad.u.net->netif = indev->ifindex;
5077 ad.u.net->family = family;
5078 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5079 return NF_DROP;
5080
5081 if (peerlbl_active) {
5082 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5083 addrp, family, peer_sid, &ad);
5084 if (err) {
5085 selinux_netlbl_err(skb, family, err, 1);
5086 return NF_DROP;
5087 }
5088 }
5089
5090 if (secmark_active)
5091 if (avc_has_perm(peer_sid, skb->secmark,
5092 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5093 return NF_DROP;
5094
5095 if (netlbl_active)
5096 /* we do this in the FORWARD path and not the POST_ROUTING
5097 * path because we want to make sure we apply the necessary
5098 * labeling before IPsec is applied so we can leverage AH
5099 * protection */
5100 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5101 return NF_DROP;
5102
5103 return NF_ACCEPT;
5104}
5105
5106static unsigned int selinux_ipv4_forward(void *priv,
5107 struct sk_buff *skb,
5108 const struct nf_hook_state *state)
5109{
5110 return selinux_ip_forward(skb, state->in, PF_INET);
5111}
5112
5113#if IS_ENABLED(CONFIG_IPV6)
5114static unsigned int selinux_ipv6_forward(void *priv,
5115 struct sk_buff *skb,
5116 const struct nf_hook_state *state)
5117{
5118 return selinux_ip_forward(skb, state->in, PF_INET6);
5119}
5120#endif /* IPV6 */
5121
5122static unsigned int selinux_ip_output(struct sk_buff *skb,
5123 u16 family)
5124{
5125 struct sock *sk;
5126 u32 sid;
5127
5128 if (!netlbl_enabled())
5129 return NF_ACCEPT;
5130
5131 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5132 * because we want to make sure we apply the necessary labeling
5133 * before IPsec is applied so we can leverage AH protection */
5134 sk = skb->sk;
5135 if (sk) {
5136 struct sk_security_struct *sksec;
5137
5138 if (sk_listener(sk))
5139 /* if the socket is the listening state then this
5140 * packet is a SYN-ACK packet which means it needs to
5141 * be labeled based on the connection/request_sock and
5142 * not the parent socket. unfortunately, we can't
5143 * lookup the request_sock yet as it isn't queued on
5144 * the parent socket until after the SYN-ACK is sent.
5145 * the "solution" is to simply pass the packet as-is
5146 * as any IP option based labeling should be copied
5147 * from the initial connection request (in the IP
5148 * layer). it is far from ideal, but until we get a
5149 * security label in the packet itself this is the
5150 * best we can do. */
5151 return NF_ACCEPT;
5152
5153 /* standard practice, label using the parent socket */
5154 sksec = sk->sk_security;
5155 sid = sksec->sid;
5156 } else
5157 sid = SECINITSID_KERNEL;
5158 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5159 return NF_DROP;
5160
5161 return NF_ACCEPT;
5162}
5163
5164static unsigned int selinux_ipv4_output(void *priv,
5165 struct sk_buff *skb,
5166 const struct nf_hook_state *state)
5167{
5168 return selinux_ip_output(skb, PF_INET);
5169}
5170
5171#if IS_ENABLED(CONFIG_IPV6)
5172static unsigned int selinux_ipv6_output(void *priv,
5173 struct sk_buff *skb,
5174 const struct nf_hook_state *state)
5175{
5176 return selinux_ip_output(skb, PF_INET6);
5177}
5178#endif /* IPV6 */
5179
5180static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5181 int ifindex,
5182 u16 family)
5183{
5184 struct sock *sk = skb_to_full_sk(skb);
5185 struct sk_security_struct *sksec;
5186 struct common_audit_data ad;
5187 struct lsm_network_audit net = {0,};
5188 char *addrp;
5189 u8 proto;
5190
5191 if (sk == NULL)
5192 return NF_ACCEPT;
5193 sksec = sk->sk_security;
5194
5195 ad.type = LSM_AUDIT_DATA_NET;
5196 ad.u.net = &net;
5197 ad.u.net->netif = ifindex;
5198 ad.u.net->family = family;
5199 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5200 return NF_DROP;
5201
5202 if (selinux_secmark_enabled())
5203 if (avc_has_perm(sksec->sid, skb->secmark,
5204 SECCLASS_PACKET, PACKET__SEND, &ad))
5205 return NF_DROP_ERR(-ECONNREFUSED);
5206
5207 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5208 return NF_DROP_ERR(-ECONNREFUSED);
5209
5210 return NF_ACCEPT;
5211}
5212
5213static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5214 const struct net_device *outdev,
5215 u16 family)
5216{
5217 u32 secmark_perm;
5218 u32 peer_sid;
5219 int ifindex = outdev->ifindex;
5220 struct sock *sk;
5221 struct common_audit_data ad;
5222 struct lsm_network_audit net = {0,};
5223 char *addrp;
5224 u8 secmark_active;
5225 u8 peerlbl_active;
5226
5227 /* If any sort of compatibility mode is enabled then handoff processing
5228 * to the selinux_ip_postroute_compat() function to deal with the
5229 * special handling. We do this in an attempt to keep this function
5230 * as fast and as clean as possible. */
5231 if (!selinux_policycap_netpeer)
5232 return selinux_ip_postroute_compat(skb, ifindex, family);
5233
5234 secmark_active = selinux_secmark_enabled();
5235 peerlbl_active = selinux_peerlbl_enabled();
5236 if (!secmark_active && !peerlbl_active)
5237 return NF_ACCEPT;
5238
5239 sk = skb_to_full_sk(skb);
5240
5241#ifdef CONFIG_XFRM
5242 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5243 * packet transformation so allow the packet to pass without any checks
5244 * since we'll have another chance to perform access control checks
5245 * when the packet is on it's final way out.
5246 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5247 * is NULL, in this case go ahead and apply access control.
5248 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5249 * TCP listening state we cannot wait until the XFRM processing
5250 * is done as we will miss out on the SA label if we do;
5251 * unfortunately, this means more work, but it is only once per
5252 * connection. */
5253 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5254 !(sk && sk_listener(sk)))
5255 return NF_ACCEPT;
5256#endif
5257
5258 if (sk == NULL) {
5259 /* Without an associated socket the packet is either coming
5260 * from the kernel or it is being forwarded; check the packet
5261 * to determine which and if the packet is being forwarded
5262 * query the packet directly to determine the security label. */
5263 if (skb->skb_iif) {
5264 secmark_perm = PACKET__FORWARD_OUT;
5265 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5266 return NF_DROP;
5267 } else {
5268 secmark_perm = PACKET__SEND;
5269 peer_sid = SECINITSID_KERNEL;
5270 }
5271 } else if (sk_listener(sk)) {
5272 /* Locally generated packet but the associated socket is in the
5273 * listening state which means this is a SYN-ACK packet. In
5274 * this particular case the correct security label is assigned
5275 * to the connection/request_sock but unfortunately we can't
5276 * query the request_sock as it isn't queued on the parent
5277 * socket until after the SYN-ACK packet is sent; the only
5278 * viable choice is to regenerate the label like we do in
5279 * selinux_inet_conn_request(). See also selinux_ip_output()
5280 * for similar problems. */
5281 u32 skb_sid;
5282 struct sk_security_struct *sksec;
5283
5284 sksec = sk->sk_security;
5285 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5286 return NF_DROP;
5287 /* At this point, if the returned skb peerlbl is SECSID_NULL
5288 * and the packet has been through at least one XFRM
5289 * transformation then we must be dealing with the "final"
5290 * form of labeled IPsec packet; since we've already applied
5291 * all of our access controls on this packet we can safely
5292 * pass the packet. */
5293 if (skb_sid == SECSID_NULL) {
5294 switch (family) {
5295 case PF_INET:
5296 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5297 return NF_ACCEPT;
5298 break;
5299 case PF_INET6:
5300 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5301 return NF_ACCEPT;
5302 break;
5303 default:
5304 return NF_DROP_ERR(-ECONNREFUSED);
5305 }
5306 }
5307 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5308 return NF_DROP;
5309 secmark_perm = PACKET__SEND;
5310 } else {
5311 /* Locally generated packet, fetch the security label from the
5312 * associated socket. */
5313 struct sk_security_struct *sksec = sk->sk_security;
5314 peer_sid = sksec->sid;
5315 secmark_perm = PACKET__SEND;
5316 }
5317
5318 ad.type = LSM_AUDIT_DATA_NET;
5319 ad.u.net = &net;
5320 ad.u.net->netif = ifindex;
5321 ad.u.net->family = family;
5322 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5323 return NF_DROP;
5324
5325 if (secmark_active)
5326 if (avc_has_perm(peer_sid, skb->secmark,
5327 SECCLASS_PACKET, secmark_perm, &ad))
5328 return NF_DROP_ERR(-ECONNREFUSED);
5329
5330 if (peerlbl_active) {
5331 u32 if_sid;
5332 u32 node_sid;
5333
5334 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5335 return NF_DROP;
5336 if (avc_has_perm(peer_sid, if_sid,
5337 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5338 return NF_DROP_ERR(-ECONNREFUSED);
5339
5340 if (sel_netnode_sid(addrp, family, &node_sid))
5341 return NF_DROP;
5342 if (avc_has_perm(peer_sid, node_sid,
5343 SECCLASS_NODE, NODE__SENDTO, &ad))
5344 return NF_DROP_ERR(-ECONNREFUSED);
5345 }
5346
5347 return NF_ACCEPT;
5348}
5349
5350static unsigned int selinux_ipv4_postroute(void *priv,
5351 struct sk_buff *skb,
5352 const struct nf_hook_state *state)
5353{
5354 return selinux_ip_postroute(skb, state->out, PF_INET);
5355}
5356
5357#if IS_ENABLED(CONFIG_IPV6)
5358static unsigned int selinux_ipv6_postroute(void *priv,
5359 struct sk_buff *skb,
5360 const struct nf_hook_state *state)
5361{
5362 return selinux_ip_postroute(skb, state->out, PF_INET6);
5363}
5364#endif /* IPV6 */
5365
5366#endif /* CONFIG_NETFILTER */
5367
5368static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5369{
5370 return selinux_nlmsg_perm(sk, skb);
5371}
5372
5373static int ipc_alloc_security(struct task_struct *task,
5374 struct kern_ipc_perm *perm,
5375 u16 sclass)
5376{
5377 struct ipc_security_struct *isec;
5378 u32 sid;
5379
5380 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5381 if (!isec)
5382 return -ENOMEM;
5383
5384 sid = task_sid(task);
5385 isec->sclass = sclass;
5386 isec->sid = sid;
5387 perm->security = isec;
5388
5389 return 0;
5390}
5391
5392static void ipc_free_security(struct kern_ipc_perm *perm)
5393{
5394 struct ipc_security_struct *isec = perm->security;
5395 perm->security = NULL;
5396 kfree(isec);
5397}
5398
5399static int msg_msg_alloc_security(struct msg_msg *msg)
5400{
5401 struct msg_security_struct *msec;
5402
5403 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5404 if (!msec)
5405 return -ENOMEM;
5406
5407 msec->sid = SECINITSID_UNLABELED;
5408 msg->security = msec;
5409
5410 return 0;
5411}
5412
5413static void msg_msg_free_security(struct msg_msg *msg)
5414{
5415 struct msg_security_struct *msec = msg->security;
5416
5417 msg->security = NULL;
5418 kfree(msec);
5419}
5420
5421static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5422 u32 perms)
5423{
5424 struct ipc_security_struct *isec;
5425 struct common_audit_data ad;
5426 u32 sid = current_sid();
5427
5428 isec = ipc_perms->security;
5429
5430 ad.type = LSM_AUDIT_DATA_IPC;
5431 ad.u.ipc_id = ipc_perms->key;
5432
5433 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5434}
5435
5436static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5437{
5438 return msg_msg_alloc_security(msg);
5439}
5440
5441static void selinux_msg_msg_free_security(struct msg_msg *msg)
5442{
5443 msg_msg_free_security(msg);
5444}
5445
5446/* message queue security operations */
5447static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
5448{
5449 struct ipc_security_struct *isec;
5450 struct common_audit_data ad;
5451 u32 sid = current_sid();
5452 int rc;
5453
5454 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
5455 if (rc)
5456 return rc;
5457
5458 isec = msq->q_perm.security;
5459
5460 ad.type = LSM_AUDIT_DATA_IPC;
5461 ad.u.ipc_id = msq->q_perm.key;
5462
5463 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5464 MSGQ__CREATE, &ad);
5465 if (rc) {
5466 ipc_free_security(&msq->q_perm);
5467 return rc;
5468 }
5469 return 0;
5470}
5471
5472static void selinux_msg_queue_free_security(struct msg_queue *msq)
5473{
5474 ipc_free_security(&msq->q_perm);
5475}
5476
5477static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5478{
5479 struct ipc_security_struct *isec;
5480 struct common_audit_data ad;
5481 u32 sid = current_sid();
5482
5483 isec = msq->q_perm.security;
5484
5485 ad.type = LSM_AUDIT_DATA_IPC;
5486 ad.u.ipc_id = msq->q_perm.key;
5487
5488 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5489 MSGQ__ASSOCIATE, &ad);
5490}
5491
5492static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5493{
5494 int err;
5495 int perms;
5496
5497 switch (cmd) {
5498 case IPC_INFO:
5499 case MSG_INFO:
5500 /* No specific object, just general system-wide information. */
5501 return task_has_system(current, SYSTEM__IPC_INFO);
5502 case IPC_STAT:
5503 case MSG_STAT:
5504 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5505 break;
5506 case IPC_SET:
5507 perms = MSGQ__SETATTR;
5508 break;
5509 case IPC_RMID:
5510 perms = MSGQ__DESTROY;
5511 break;
5512 default:
5513 return 0;
5514 }
5515
5516 err = ipc_has_perm(&msq->q_perm, perms);
5517 return err;
5518}
5519
5520static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5521{
5522 struct ipc_security_struct *isec;
5523 struct msg_security_struct *msec;
5524 struct common_audit_data ad;
5525 u32 sid = current_sid();
5526 int rc;
5527
5528 isec = msq->q_perm.security;
5529 msec = msg->security;
5530
5531 /*
5532 * First time through, need to assign label to the message
5533 */
5534 if (msec->sid == SECINITSID_UNLABELED) {
5535 /*
5536 * Compute new sid based on current process and
5537 * message queue this message will be stored in
5538 */
5539 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5540 NULL, &msec->sid);
5541 if (rc)
5542 return rc;
5543 }
5544
5545 ad.type = LSM_AUDIT_DATA_IPC;
5546 ad.u.ipc_id = msq->q_perm.key;
5547
5548 /* Can this process write to the queue? */
5549 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5550 MSGQ__WRITE, &ad);
5551 if (!rc)
5552 /* Can this process send the message */
5553 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5554 MSG__SEND, &ad);
5555 if (!rc)
5556 /* Can the message be put in the queue? */
5557 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5558 MSGQ__ENQUEUE, &ad);
5559
5560 return rc;
5561}
5562
5563static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5564 struct task_struct *target,
5565 long type, int mode)
5566{
5567 struct ipc_security_struct *isec;
5568 struct msg_security_struct *msec;
5569 struct common_audit_data ad;
5570 u32 sid = task_sid(target);
5571 int rc;
5572
5573 isec = msq->q_perm.security;
5574 msec = msg->security;
5575
5576 ad.type = LSM_AUDIT_DATA_IPC;
5577 ad.u.ipc_id = msq->q_perm.key;
5578
5579 rc = avc_has_perm(sid, isec->sid,
5580 SECCLASS_MSGQ, MSGQ__READ, &ad);
5581 if (!rc)
5582 rc = avc_has_perm(sid, msec->sid,
5583 SECCLASS_MSG, MSG__RECEIVE, &ad);
5584 return rc;
5585}
5586
5587/* Shared Memory security operations */
5588static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5589{
5590 struct ipc_security_struct *isec;
5591 struct common_audit_data ad;
5592 u32 sid = current_sid();
5593 int rc;
5594
5595 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5596 if (rc)
5597 return rc;
5598
5599 isec = shp->shm_perm.security;
5600
5601 ad.type = LSM_AUDIT_DATA_IPC;
5602 ad.u.ipc_id = shp->shm_perm.key;
5603
5604 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5605 SHM__CREATE, &ad);
5606 if (rc) {
5607 ipc_free_security(&shp->shm_perm);
5608 return rc;
5609 }
5610 return 0;
5611}
5612
5613static void selinux_shm_free_security(struct shmid_kernel *shp)
5614{
5615 ipc_free_security(&shp->shm_perm);
5616}
5617
5618static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5619{
5620 struct ipc_security_struct *isec;
5621 struct common_audit_data ad;
5622 u32 sid = current_sid();
5623
5624 isec = shp->shm_perm.security;
5625
5626 ad.type = LSM_AUDIT_DATA_IPC;
5627 ad.u.ipc_id = shp->shm_perm.key;
5628
5629 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5630 SHM__ASSOCIATE, &ad);
5631}
5632
5633/* Note, at this point, shp is locked down */
5634static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5635{
5636 int perms;
5637 int err;
5638
5639 switch (cmd) {
5640 case IPC_INFO:
5641 case SHM_INFO:
5642 /* No specific object, just general system-wide information. */
5643 return task_has_system(current, SYSTEM__IPC_INFO);
5644 case IPC_STAT:
5645 case SHM_STAT:
5646 perms = SHM__GETATTR | SHM__ASSOCIATE;
5647 break;
5648 case IPC_SET:
5649 perms = SHM__SETATTR;
5650 break;
5651 case SHM_LOCK:
5652 case SHM_UNLOCK:
5653 perms = SHM__LOCK;
5654 break;
5655 case IPC_RMID:
5656 perms = SHM__DESTROY;
5657 break;
5658 default:
5659 return 0;
5660 }
5661
5662 err = ipc_has_perm(&shp->shm_perm, perms);
5663 return err;
5664}
5665
5666static int selinux_shm_shmat(struct shmid_kernel *shp,
5667 char __user *shmaddr, int shmflg)
5668{
5669 u32 perms;
5670
5671 if (shmflg & SHM_RDONLY)
5672 perms = SHM__READ;
5673 else
5674 perms = SHM__READ | SHM__WRITE;
5675
5676 return ipc_has_perm(&shp->shm_perm, perms);
5677}
5678
5679/* Semaphore security operations */
5680static int selinux_sem_alloc_security(struct sem_array *sma)
5681{
5682 struct ipc_security_struct *isec;
5683 struct common_audit_data ad;
5684 u32 sid = current_sid();
5685 int rc;
5686
5687 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5688 if (rc)
5689 return rc;
5690
5691 isec = sma->sem_perm.security;
5692
5693 ad.type = LSM_AUDIT_DATA_IPC;
5694 ad.u.ipc_id = sma->sem_perm.key;
5695
5696 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5697 SEM__CREATE, &ad);
5698 if (rc) {
5699 ipc_free_security(&sma->sem_perm);
5700 return rc;
5701 }
5702 return 0;
5703}
5704
5705static void selinux_sem_free_security(struct sem_array *sma)
5706{
5707 ipc_free_security(&sma->sem_perm);
5708}
5709
5710static int selinux_sem_associate(struct sem_array *sma, int semflg)
5711{
5712 struct ipc_security_struct *isec;
5713 struct common_audit_data ad;
5714 u32 sid = current_sid();
5715
5716 isec = sma->sem_perm.security;
5717
5718 ad.type = LSM_AUDIT_DATA_IPC;
5719 ad.u.ipc_id = sma->sem_perm.key;
5720
5721 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5722 SEM__ASSOCIATE, &ad);
5723}
5724
5725/* Note, at this point, sma is locked down */
5726static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5727{
5728 int err;
5729 u32 perms;
5730
5731 switch (cmd) {
5732 case IPC_INFO:
5733 case SEM_INFO:
5734 /* No specific object, just general system-wide information. */
5735 return task_has_system(current, SYSTEM__IPC_INFO);
5736 case GETPID:
5737 case GETNCNT:
5738 case GETZCNT:
5739 perms = SEM__GETATTR;
5740 break;
5741 case GETVAL:
5742 case GETALL:
5743 perms = SEM__READ;
5744 break;
5745 case SETVAL:
5746 case SETALL:
5747 perms = SEM__WRITE;
5748 break;
5749 case IPC_RMID:
5750 perms = SEM__DESTROY;
5751 break;
5752 case IPC_SET:
5753 perms = SEM__SETATTR;
5754 break;
5755 case IPC_STAT:
5756 case SEM_STAT:
5757 perms = SEM__GETATTR | SEM__ASSOCIATE;
5758 break;
5759 default:
5760 return 0;
5761 }
5762
5763 err = ipc_has_perm(&sma->sem_perm, perms);
5764 return err;
5765}
5766
5767static int selinux_sem_semop(struct sem_array *sma,
5768 struct sembuf *sops, unsigned nsops, int alter)
5769{
5770 u32 perms;
5771
5772 if (alter)
5773 perms = SEM__READ | SEM__WRITE;
5774 else
5775 perms = SEM__READ;
5776
5777 return ipc_has_perm(&sma->sem_perm, perms);
5778}
5779
5780static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5781{
5782 u32 av = 0;
5783
5784 av = 0;
5785 if (flag & S_IRUGO)
5786 av |= IPC__UNIX_READ;
5787 if (flag & S_IWUGO)
5788 av |= IPC__UNIX_WRITE;
5789
5790 if (av == 0)
5791 return 0;
5792
5793 return ipc_has_perm(ipcp, av);
5794}
5795
5796static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5797{
5798 struct ipc_security_struct *isec = ipcp->security;
5799 *secid = isec->sid;
5800}
5801
5802static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5803{
5804 if (inode)
5805 inode_doinit_with_dentry(inode, dentry);
5806}
5807
5808static int selinux_getprocattr(struct task_struct *p,
5809 char *name, char **value)
5810{
5811 const struct task_security_struct *__tsec;
5812 u32 sid;
5813 int error;
5814 unsigned len;
5815
5816 if (current != p) {
5817 error = current_has_perm(p, PROCESS__GETATTR);
5818 if (error)
5819 return error;
5820 }
5821
5822 rcu_read_lock();
5823 __tsec = __task_cred(p)->security;
5824
5825 if (!strcmp(name, "current"))
5826 sid = __tsec->sid;
5827 else if (!strcmp(name, "prev"))
5828 sid = __tsec->osid;
5829 else if (!strcmp(name, "exec"))
5830 sid = __tsec->exec_sid;
5831 else if (!strcmp(name, "fscreate"))
5832 sid = __tsec->create_sid;
5833 else if (!strcmp(name, "keycreate"))
5834 sid = __tsec->keycreate_sid;
5835 else if (!strcmp(name, "sockcreate"))
5836 sid = __tsec->sockcreate_sid;
5837 else
5838 goto invalid;
5839 rcu_read_unlock();
5840
5841 if (!sid)
5842 return 0;
5843
5844 error = security_sid_to_context(sid, value, &len);
5845 if (error)
5846 return error;
5847 return len;
5848
5849invalid:
5850 rcu_read_unlock();
5851 return -EINVAL;
5852}
5853
5854static int selinux_setprocattr(struct task_struct *p,
5855 char *name, void *value, size_t size)
5856{
5857 struct task_security_struct *tsec;
5858 struct cred *new;
5859 u32 sid = 0, ptsid;
5860 int error;
5861 char *str = value;
5862
5863 if (current != p) {
5864 /* SELinux only allows a process to change its own
5865 security attributes. */
5866 return -EACCES;
5867 }
5868
5869 /*
5870 * Basic control over ability to set these attributes at all.
5871 * current == p, but we'll pass them separately in case the
5872 * above restriction is ever removed.
5873 */
5874 if (!strcmp(name, "exec"))
5875 error = current_has_perm(p, PROCESS__SETEXEC);
5876 else if (!strcmp(name, "fscreate"))
5877 error = current_has_perm(p, PROCESS__SETFSCREATE);
5878 else if (!strcmp(name, "keycreate"))
5879 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5880 else if (!strcmp(name, "sockcreate"))
5881 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5882 else if (!strcmp(name, "current"))
5883 error = current_has_perm(p, PROCESS__SETCURRENT);
5884 else
5885 error = -EINVAL;
5886 if (error)
5887 return error;
5888
5889 /* Obtain a SID for the context, if one was specified. */
5890 if (size && str[0] && str[0] != '\n') {
5891 if (str[size-1] == '\n') {
5892 str[size-1] = 0;
5893 size--;
5894 }
5895 error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5896 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5897 if (!capable(CAP_MAC_ADMIN)) {
5898 struct audit_buffer *ab;
5899 size_t audit_size;
5900
5901 /* We strip a nul only if it is at the end, otherwise the
5902 * context contains a nul and we should audit that */
5903 if (str[size - 1] == '\0')
5904 audit_size = size - 1;
5905 else
5906 audit_size = size;
5907 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5908 audit_log_format(ab, "op=fscreate invalid_context=");
5909 audit_log_n_untrustedstring(ab, value, audit_size);
5910 audit_log_end(ab);
5911
5912 return error;
5913 }
5914 error = security_context_to_sid_force(value, size,
5915 &sid);
5916 }
5917 if (error)
5918 return error;
5919 }
5920
5921 new = prepare_creds();
5922 if (!new)
5923 return -ENOMEM;
5924
5925 /* Permission checking based on the specified context is
5926 performed during the actual operation (execve,
5927 open/mkdir/...), when we know the full context of the
5928 operation. See selinux_bprm_set_creds for the execve
5929 checks and may_create for the file creation checks. The
5930 operation will then fail if the context is not permitted. */
5931 tsec = new->security;
5932 if (!strcmp(name, "exec")) {
5933 tsec->exec_sid = sid;
5934 } else if (!strcmp(name, "fscreate")) {
5935 tsec->create_sid = sid;
5936 } else if (!strcmp(name, "keycreate")) {
5937 error = may_create_key(sid, p);
5938 if (error)
5939 goto abort_change;
5940 tsec->keycreate_sid = sid;
5941 } else if (!strcmp(name, "sockcreate")) {
5942 tsec->sockcreate_sid = sid;
5943 } else if (!strcmp(name, "current")) {
5944 error = -EINVAL;
5945 if (sid == 0)
5946 goto abort_change;
5947
5948 /* Only allow single threaded processes to change context */
5949 error = -EPERM;
5950 if (!current_is_single_threaded()) {
5951 error = security_bounded_transition(tsec->sid, sid);
5952 if (error)
5953 goto abort_change;
5954 }
5955
5956 /* Check permissions for the transition. */
5957 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5958 PROCESS__DYNTRANSITION, NULL);
5959 if (error)
5960 goto abort_change;
5961
5962 /* Check for ptracing, and update the task SID if ok.
5963 Otherwise, leave SID unchanged and fail. */
5964 ptsid = ptrace_parent_sid(p);
5965 if (ptsid != 0) {
5966 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5967 PROCESS__PTRACE, NULL);
5968 if (error)
5969 goto abort_change;
5970 }
5971
5972 tsec->sid = sid;
5973 } else {
5974 error = -EINVAL;
5975 goto abort_change;
5976 }
5977
5978 commit_creds(new);
5979 return size;
5980
5981abort_change:
5982 abort_creds(new);
5983 return error;
5984}
5985
5986static int selinux_ismaclabel(const char *name)
5987{
5988 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5989}
5990
5991static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5992{
5993 return security_sid_to_context(secid, secdata, seclen);
5994}
5995
5996static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5997{
5998 return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5999}
6000
6001static void selinux_release_secctx(char *secdata, u32 seclen)
6002{
6003 kfree(secdata);
6004}
6005
6006static void selinux_inode_invalidate_secctx(struct inode *inode)
6007{
6008 struct inode_security_struct *isec = inode->i_security;
6009
6010 spin_lock(&isec->lock);
6011 isec->initialized = LABEL_INVALID;
6012 spin_unlock(&isec->lock);
6013}
6014
6015/*
6016 * called with inode->i_mutex locked
6017 */
6018static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6019{
6020 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
6021}
6022
6023/*
6024 * called with inode->i_mutex locked
6025 */
6026static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6027{
6028 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6029}
6030
6031static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6032{
6033 int len = 0;
6034 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6035 ctx, true);
6036 if (len < 0)
6037 return len;
6038 *ctxlen = len;
6039 return 0;
6040}
6041#ifdef CONFIG_KEYS
6042
6043static int selinux_key_alloc(struct key *k, const struct cred *cred,
6044 unsigned long flags)
6045{
6046 const struct task_security_struct *tsec;
6047 struct key_security_struct *ksec;
6048
6049 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6050 if (!ksec)
6051 return -ENOMEM;
6052
6053 tsec = cred->security;
6054 if (tsec->keycreate_sid)
6055 ksec->sid = tsec->keycreate_sid;
6056 else
6057 ksec->sid = tsec->sid;
6058
6059 k->security = ksec;
6060 return 0;
6061}
6062
6063static void selinux_key_free(struct key *k)
6064{
6065 struct key_security_struct *ksec = k->security;
6066
6067 k->security = NULL;
6068 kfree(ksec);
6069}
6070
6071static int selinux_key_permission(key_ref_t key_ref,
6072 const struct cred *cred,
6073 unsigned perm)
6074{
6075 struct key *key;
6076 struct key_security_struct *ksec;
6077 u32 sid;
6078
6079 /* if no specific permissions are requested, we skip the
6080 permission check. No serious, additional covert channels
6081 appear to be created. */
6082 if (perm == 0)
6083 return 0;
6084
6085 sid = cred_sid(cred);
6086
6087 key = key_ref_to_ptr(key_ref);
6088 ksec = key->security;
6089
6090 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6091}
6092
6093static int selinux_key_getsecurity(struct key *key, char **_buffer)
6094{
6095 struct key_security_struct *ksec = key->security;
6096 char *context = NULL;
6097 unsigned len;
6098 int rc;
6099
6100 rc = security_sid_to_context(ksec->sid, &context, &len);
6101 if (!rc)
6102 rc = len;
6103 *_buffer = context;
6104 return rc;
6105}
6106
6107#endif
6108
6109static struct security_hook_list selinux_hooks[] = {
6110 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6111 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6112 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6113 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6114
6115 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6116 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6117 LSM_HOOK_INIT(capget, selinux_capget),
6118 LSM_HOOK_INIT(capset, selinux_capset),
6119 LSM_HOOK_INIT(capable, selinux_capable),
6120 LSM_HOOK_INIT(quotactl, selinux_quotactl),
6121 LSM_HOOK_INIT(quota_on, selinux_quota_on),
6122 LSM_HOOK_INIT(syslog, selinux_syslog),
6123 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6124
6125 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6126
6127 LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
6128 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6129 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6130 LSM_HOOK_INIT(bprm_secureexec, selinux_bprm_secureexec),
6131
6132 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
6133 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6134 LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
6135 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6136 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6137 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6138 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6139 LSM_HOOK_INIT(sb_mount, selinux_mount),
6140 LSM_HOOK_INIT(sb_umount, selinux_umount),
6141 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6142 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6143 LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),
6144
6145 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6146 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6147
6148 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
6149 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6150 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6151 LSM_HOOK_INIT(inode_create, selinux_inode_create),
6152 LSM_HOOK_INIT(inode_link, selinux_inode_link),
6153 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6154 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6155 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6156 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6157 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6158 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6159 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
6160 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
6161 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
6162 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
6163 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
6164 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
6165 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
6166 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
6167 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
6168 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
6169 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
6170 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
6171 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
6172 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
6173 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6174 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6175
6176 LSM_HOOK_INIT(file_permission, selinux_file_permission),
6177 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
6178 LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
6179 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
6180 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
6181 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
6182 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
6183 LSM_HOOK_INIT(file_lock, selinux_file_lock),
6184 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
6185 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
6186 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
6187 LSM_HOOK_INIT(file_receive, selinux_file_receive),
6188
6189 LSM_HOOK_INIT(file_open, selinux_file_open),
6190
6191 LSM_HOOK_INIT(task_create, selinux_task_create),
6192 LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
6193 LSM_HOOK_INIT(cred_free, selinux_cred_free),
6194 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
6195 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
6196 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
6197 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
6198 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6199 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6200 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
6201 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
6202 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
6203 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
6204 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
6205 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
6206 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6207 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
6208 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
6209 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
6210 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
6211 LSM_HOOK_INIT(task_kill, selinux_task_kill),
6212 LSM_HOOK_INIT(task_wait, selinux_task_wait),
6213 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
6214
6215 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
6216 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
6217
6218 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
6219 LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),
6220
6221 LSM_HOOK_INIT(msg_queue_alloc_security,
6222 selinux_msg_queue_alloc_security),
6223 LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
6224 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
6225 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
6226 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
6227 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
6228
6229 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
6230 LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
6231 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
6232 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
6233 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
6234
6235 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
6236 LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
6237 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
6238 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
6239 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
6240
6241 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
6242
6243 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
6244 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
6245
6246 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
6247 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
6248 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
6249 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
6250 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6251 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
6252 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
6253 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
6254
6255 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
6256 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
6257
6258 LSM_HOOK_INIT(socket_create, selinux_socket_create),
6259 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
6260 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
6261 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
6262 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
6263 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
6264 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
6265 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
6266 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
6267 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
6268 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
6269 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
6270 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
6271 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
6272 LSM_HOOK_INIT(socket_getpeersec_stream,
6273 selinux_socket_getpeersec_stream),
6274 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
6275 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
6276 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
6277 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
6278 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
6279 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
6280 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
6281 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
6282 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
6283 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
6284 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
6285 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
6286 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
6287 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
6288 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
6289 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
6290 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
6291 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
6292 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
6293
6294#ifdef CONFIG_SECURITY_NETWORK_XFRM
6295 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
6296 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
6297 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
6298 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
6299 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
6300 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
6301 selinux_xfrm_state_alloc_acquire),
6302 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
6303 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
6304 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
6305 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
6306 selinux_xfrm_state_pol_flow_match),
6307 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
6308#endif
6309
6310#ifdef CONFIG_KEYS
6311 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
6312 LSM_HOOK_INIT(key_free, selinux_key_free),
6313 LSM_HOOK_INIT(key_permission, selinux_key_permission),
6314 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
6315#endif
6316
6317#ifdef CONFIG_AUDIT
6318 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
6319 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
6320 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
6321 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
6322#endif
6323};
6324
6325static __init int selinux_init(void)
6326{
6327 if (!security_module_enable("selinux")) {
6328 selinux_enabled = 0;
6329 return 0;
6330 }
6331
6332 if (!selinux_enabled) {
6333 printk(KERN_INFO "SELinux: Disabled at boot.\n");
6334 return 0;
6335 }
6336
6337 printk(KERN_INFO "SELinux: Initializing.\n");
6338
6339 /* Set the security state for the initial task. */
6340 cred_init_security();
6341
6342 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
6343
6344 sel_inode_cache = kmem_cache_create("selinux_inode_security",
6345 sizeof(struct inode_security_struct),
6346 0, SLAB_PANIC, NULL);
6347 file_security_cache = kmem_cache_create("selinux_file_security",
6348 sizeof(struct file_security_struct),
6349 0, SLAB_PANIC, NULL);
6350 avc_init();
6351
6352 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
6353
6354 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
6355 panic("SELinux: Unable to register AVC netcache callback\n");
6356
6357 if (selinux_enforcing)
6358 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
6359 else
6360 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
6361
6362 return 0;
6363}
6364
6365static void delayed_superblock_init(struct super_block *sb, void *unused)
6366{
6367 superblock_doinit(sb, NULL);
6368}
6369
6370void selinux_complete_init(void)
6371{
6372 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
6373
6374 /* Set up any superblocks initialized prior to the policy load. */
6375 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
6376 iterate_supers(delayed_superblock_init, NULL);
6377}
6378
6379/* SELinux requires early initialization in order to label
6380 all processes and objects when they are created. */
6381security_initcall(selinux_init);
6382
6383#if defined(CONFIG_NETFILTER)
6384
6385static struct nf_hook_ops selinux_nf_ops[] = {
6386 {
6387 .hook = selinux_ipv4_postroute,
6388 .pf = NFPROTO_IPV4,
6389 .hooknum = NF_INET_POST_ROUTING,
6390 .priority = NF_IP_PRI_SELINUX_LAST,
6391 },
6392 {
6393 .hook = selinux_ipv4_forward,
6394 .pf = NFPROTO_IPV4,
6395 .hooknum = NF_INET_FORWARD,
6396 .priority = NF_IP_PRI_SELINUX_FIRST,
6397 },
6398 {
6399 .hook = selinux_ipv4_output,
6400 .pf = NFPROTO_IPV4,
6401 .hooknum = NF_INET_LOCAL_OUT,
6402 .priority = NF_IP_PRI_SELINUX_FIRST,
6403 },
6404#if IS_ENABLED(CONFIG_IPV6)
6405 {
6406 .hook = selinux_ipv6_postroute,
6407 .pf = NFPROTO_IPV6,
6408 .hooknum = NF_INET_POST_ROUTING,
6409 .priority = NF_IP6_PRI_SELINUX_LAST,
6410 },
6411 {
6412 .hook = selinux_ipv6_forward,
6413 .pf = NFPROTO_IPV6,
6414 .hooknum = NF_INET_FORWARD,
6415 .priority = NF_IP6_PRI_SELINUX_FIRST,
6416 },
6417 {
6418 .hook = selinux_ipv6_output,
6419 .pf = NFPROTO_IPV6,
6420 .hooknum = NF_INET_LOCAL_OUT,
6421 .priority = NF_IP6_PRI_SELINUX_FIRST,
6422 },
6423#endif /* IPV6 */
6424};
6425
6426static int __init selinux_nf_ip_init(void)
6427{
6428 int err;
6429
6430 if (!selinux_enabled)
6431 return 0;
6432
6433 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
6434
6435 err = nf_register_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6436 if (err)
6437 panic("SELinux: nf_register_hooks: error %d\n", err);
6438
6439 return 0;
6440}
6441
6442__initcall(selinux_nf_ip_init);
6443
6444#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6445static void selinux_nf_ip_exit(void)
6446{
6447 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
6448
6449 nf_unregister_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6450}
6451#endif
6452
6453#else /* CONFIG_NETFILTER */
6454
6455#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6456#define selinux_nf_ip_exit()
6457#endif
6458
6459#endif /* CONFIG_NETFILTER */
6460
6461#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6462static int selinux_disabled;
6463
6464int selinux_disable(void)
6465{
6466 if (ss_initialized) {
6467 /* Not permitted after initial policy load. */
6468 return -EINVAL;
6469 }
6470
6471 if (selinux_disabled) {
6472 /* Only do this once. */
6473 return -EINVAL;
6474 }
6475
6476 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
6477
6478 selinux_disabled = 1;
6479 selinux_enabled = 0;
6480
6481 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
6482
6483 /* Try to destroy the avc node cache */
6484 avc_disable();
6485
6486 /* Unregister netfilter hooks. */
6487 selinux_nf_ip_exit();
6488
6489 /* Unregister selinuxfs. */
6490 exit_sel_fs();
6491
6492 return 0;
6493}
6494#endif