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
111 struct selinux_state selinux_state;
112
113 /* SECMARK reference count */
114 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
115
116 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
117 static int selinux_enforcing_boot __initdata;
118
enforcing_setup(char * str)119 static 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
131 int selinux_enabled_boot __initdata = 1;
132 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
selinux_enabled_setup(char * str)133 static 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
checkreqprot_setup(char * str)143 static 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 */
selinux_secmark_enabled(void)166 static int selinux_secmark_enabled(void)
167 {
168 return (selinux_policycap_alwaysnetwork() ||
169 atomic_read(&selinux_secmark_refcount));
170 }
171
172 /**
173 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
174 *
175 * Description:
176 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true
177 * (1) if any are enabled or false (0) if neither are enabled. If the
178 * always_check_network policy capability is enabled, peer labeling
179 * is always considered enabled.
180 *
181 */
selinux_peerlbl_enabled(void)182 static int selinux_peerlbl_enabled(void)
183 {
184 return (selinux_policycap_alwaysnetwork() ||
185 netlbl_enabled() || selinux_xfrm_enabled());
186 }
187
selinux_netcache_avc_callback(u32 event)188 static int selinux_netcache_avc_callback(u32 event)
189 {
190 if (event == AVC_CALLBACK_RESET) {
191 sel_netif_flush();
192 sel_netnode_flush();
193 sel_netport_flush();
194 synchronize_net();
195 }
196 return 0;
197 }
198
selinux_lsm_notifier_avc_callback(u32 event)199 static 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 */
cred_init_security(void)212 static 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 */
cred_sid(const struct cred * cred)223 static 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
__ad_net_init(struct common_audit_data * ad,struct lsm_network_audit * net,int ifindex,struct sock * sk,u16 family)231 static 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
ad_net_init_from_sk(struct common_audit_data * ad,struct lsm_network_audit * net,struct sock * sk)242 static 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
ad_net_init_from_iif(struct common_audit_data * ad,struct lsm_network_audit * net,int ifindex,u16 family)249 static 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 */
task_sid_obj(const struct task_struct * task)259 static 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
269 static 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 */
__inode_security_revalidate(struct inode * inode,struct dentry * dentry,bool may_sleep)277 static 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
inode_security_novalidate(struct inode * inode)305 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
306 {
307 return selinux_inode(inode);
308 }
309
inode_security_rcu(struct inode * inode,bool rcu)310 static 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 */
inode_security(struct inode * inode)323 static struct inode_security_struct *inode_security(struct inode *inode)
324 {
325 __inode_security_revalidate(inode, NULL, true);
326 return selinux_inode(inode);
327 }
328
backing_inode_security_novalidate(struct dentry * dentry)329 static 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 */
backing_inode_security(struct dentry * dentry)339 static 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
inode_free_security(struct inode * inode)347 static 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
372 struct selinux_mnt_opts {
373 u32 fscontext_sid;
374 u32 context_sid;
375 u32 rootcontext_sid;
376 u32 defcontext_sid;
377 };
378
selinux_free_mnt_opts(void * mnt_opts)379 static void selinux_free_mnt_opts(void *mnt_opts)
380 {
381 kfree(mnt_opts);
382 }
383
384 enum {
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}
394 static 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
match_opt_prefix(char * s,int l,char ** arg)408 static int match_opt_prefix(char *s, int l, char **arg)
409 {
410 unsigned 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
may_context_mount_sb_relabel(u32 sid,struct superblock_security_struct * sbsec,const struct cred * cred)429 static 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
may_context_mount_inode_relabel(u32 sid,struct superblock_security_struct * sbsec,const struct cred * cred)446 static 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
selinux_is_genfs_special_handling(struct super_block * sb)462 static 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
selinux_is_sblabel_mnt(struct super_block * sb)475 static 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
sb_check_xattr_support(struct super_block * sb)503 static 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
538 fallback:
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
sb_finish_set_opts(struct super_block * sb)552 static 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
bad_option(struct superblock_security_struct * sbsec,char flag,u32 old_sid,u32 new_sid)604 static 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 */
selinux_set_mnt_opts(struct super_block * sb,void * mnt_opts,unsigned long kern_flags,unsigned long * set_kern_flags)628 static 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
863 out_set_opts:
864 rc = sb_finish_set_opts(sb);
865 out:
866 mutex_unlock(&sbsec->lock);
867 return rc;
868 out_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
selinux_cmp_sb_context(const struct super_block * oldsb,const struct super_block * newsb)876 static 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;
899 mismatch:
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
selinux_sb_clone_mnt_opts(const struct super_block * oldsb,struct super_block * newsb,unsigned long kern_flags,unsigned long * set_kern_flags)906 static 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);
989 out:
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 */
selinux_add_opt(int token,const char * s,void ** mnt_opts)997 static 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
1052 err:
1053 pr_warn(SEL_MOUNT_FAIL_MSG);
1054 return -EINVAL;
1055 }
1056
show_sid(struct seq_file * m,u32 sid)1057 static 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
selinux_sb_show_options(struct seq_file * m,struct super_block * sb)1078 static 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
inode_mode_to_security_class(umode_t mode)1126 static 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
default_protocol_stream(int protocol)1149 static inline int default_protocol_stream(int protocol)
1150 {
1151 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1152 protocol == IPPROTO_MPTCP);
1153 }
1154
default_protocol_dgram(int protocol)1155 static inline int default_protocol_dgram(int protocol)
1156 {
1157 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1158 }
1159
socket_type_to_security_class(int family,int type,int protocol)1160 static 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
selinux_genfs_get_sid(struct dentry * dentry,u16 tclass,u16 flags,u32 * sid)1314 static 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
inode_doinit_use_xattr(struct inode * inode,struct dentry * dentry,u32 def_sid,u32 * sid)1352 static 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. */
inode_doinit_with_dentry(struct inode * inode,struct dentry * opt_dentry)1414 static 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
1567 out:
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
1578 out_unlock:
1579 spin_unlock(&isec->lock);
1580 return rc;
1581
1582 out_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. */
signal_to_av(int sig)1593 static 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. */
cred_has_capability(const struct cred * cred,int cap,unsigned int opts,bool initns)1624 static 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). */
inode_has_perm(const struct cred * cred,struct inode * inode,u32 perms,struct common_audit_data * adp)1662 static 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. */
dentry_has_perm(const struct cred * cred,struct dentry * dentry,u32 av)1682 static 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. */
path_has_perm(const struct cred * cred,const struct path * path,u32 av)1698 static 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. */
file_path_has_perm(const struct cred * cred,struct file * file,u32 av)1712 static 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
1724 static 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. */
file_has_perm(const struct cred * cred,struct file * file,u32 av)1735 static 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
1768 out:
1769 return rc;
1770 }
1771
1772 /*
1773 * Determine the label for an inode that might be unioned.
1774 */
1775 static int
selinux_determine_inode_label(const struct task_security_struct * tsec,struct inode * dir,const struct qstr * name,u16 tclass,u32 * _new_isid)1776 selinux_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. */
may_create(struct inode * dir,struct dentry * dentry,u16 tclass)1801 static 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. */
may_link(struct inode * dir,struct dentry * dentry,int kind)1845 static 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
may_rename(struct inode * old_dir,struct dentry * old_dentry,struct inode * new_dir,struct dentry * new_dentry)1888 static 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. */
superblock_has_perm(const struct cred * cred,const struct super_block * sb,u32 perms,struct common_audit_data * ad)1944 static 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. */
file_mask_to_av(int mode,int mask)1957 static 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. */
file_to_av(const struct file * file)1985 static 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 */
open_file_to_av(struct file * file)2011 static 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
selinux_binder_set_context_mgr(const struct cred * mgr)2025 static 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
selinux_binder_transaction(const struct cred * from,const struct cred * to)2031 static 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
selinux_binder_transfer_binder(const struct cred * from,const struct cred * to)2050 static 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
selinux_binder_transfer_file(const struct cred * from,const struct cred * to,const struct file * file)2058 static 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
selinux_ptrace_access_check(struct task_struct * child,unsigned int mode)2095 static 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
selinux_ptrace_traceme(struct task_struct * parent)2109 static 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
selinux_capget(const struct task_struct * target,kernel_cap_t * effective,kernel_cap_t * inheritable,kernel_cap_t * permitted)2115 static 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
selinux_capset(struct cred * new,const struct cred * old,const kernel_cap_t * effective,const kernel_cap_t * inheritable,const kernel_cap_t * permitted)2122 static 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
selinux_capable(const struct cred * cred,struct user_namespace * ns,int cap,unsigned int opts)2141 static 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
selinux_quotactl(int cmds,int type,int id,const struct super_block * sb)2147 static 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
selinux_quota_on(struct dentry * dentry)2182 static 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
selinux_syslog(int type)2189 static 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 */
selinux_vm_enough_memory(struct mm_struct * mm,long pages)2216 static 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
ptrace_parent_sid(void)2224 static 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
check_nnp_nosuid(const struct linux_binprm * bprm,const struct task_security_struct * old_tsec,const struct task_security_struct * new_tsec)2238 static 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
selinux_bprm_creds_for_exec(struct linux_binprm * bprm)2291 static 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
match_file(const void * p,struct file * file,unsigned fd)2412 static 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. */
flush_unauthorized_files(const struct cred * cred,struct files_struct * files)2418 static 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 */
selinux_bprm_committing_creds(const struct linux_binprm * bprm)2469 static 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 */
selinux_bprm_committed_creds(const struct linux_binprm * bprm)2515 static 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
selinux_sb_alloc_security(struct super_block * sb)2558 static 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
opt_len(const char * s)2572 static 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
selinux_sb_eat_lsm_opts(char * options,void ** mnt_opts)2587 static 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
2640 free_opt:
2641 if (*mnt_opts) {
2642 selinux_free_mnt_opts(*mnt_opts);
2643 *mnt_opts = NULL;
2644 }
2645 return rc;
2646 }
2647
selinux_sb_mnt_opts_compat(struct super_block * sb,void * mnt_opts)2648 static 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
selinux_sb_remount(struct super_block * sb,void * mnt_opts)2693 static 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
2728 out_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
selinux_sb_kern_mount(const struct super_block * sb)2735 static 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
selinux_sb_statfs(struct dentry * dentry)2745 static 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
selinux_mount(const char * dev_name,const struct path * path,const char * type,unsigned long flags,void * data)2755 static 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
selinux_move_mount(const struct path * from_path,const struct path * to_path)2770 static 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
selinux_umount(struct vfsmount * mnt,int flags)2778 static 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
selinux_fs_context_submount(struct fs_context * fc,struct super_block * reference)2786 static 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
selinux_fs_context_dup(struct fs_context * fc,struct fs_context * src_fc)2813 static 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
2825 static 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
selinux_fs_context_parse_param(struct fs_context * fc,struct fs_parameter * param)2834 static 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
selinux_inode_alloc_security(struct inode * inode)2849 static 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
selinux_inode_free_security(struct inode * inode)2865 static void selinux_inode_free_security(struct inode *inode)
2866 {
2867 inode_free_security(inode);
2868 }
2869
selinux_dentry_init_security(struct dentry * dentry,int mode,const struct qstr * name,const char ** xattr_name,struct lsm_context * cp)2870 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2871 const struct qstr *name,
2872 const char **xattr_name,
2873 struct lsm_context *cp)
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 cp->id = LSM_ID_SELINUX;
2889 return security_sid_to_context(newsid, &cp->context, &cp->len);
2890 }
2891
selinux_dentry_create_files_as(struct dentry * dentry,int mode,struct qstr * name,const struct cred * old,struct cred * new)2892 static 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
selinux_inode_init_security(struct inode * inode,struct inode * dir,const struct qstr * qstr,struct xattr * xattrs,int * xattr_count)2913 static 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
selinux_inode_init_security_anon(struct inode * inode,const struct qstr * name,const struct inode * context_inode)2958 static 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
selinux_inode_create(struct inode * dir,struct dentry * dentry,umode_t mode)3013 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3014 {
3015 return may_create(dir, dentry, SECCLASS_FILE);
3016 }
3017
selinux_inode_link(struct dentry * old_dentry,struct inode * dir,struct dentry * new_dentry)3018 static 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
selinux_inode_unlink(struct inode * dir,struct dentry * dentry)3023 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3024 {
3025 return may_link(dir, dentry, MAY_UNLINK);
3026 }
3027
selinux_inode_symlink(struct inode * dir,struct dentry * dentry,const char * name)3028 static 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
selinux_inode_mkdir(struct inode * dir,struct dentry * dentry,umode_t mask)3033 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3034 {
3035 return may_create(dir, dentry, SECCLASS_DIR);
3036 }
3037
selinux_inode_rmdir(struct inode * dir,struct dentry * dentry)3038 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3039 {
3040 return may_link(dir, dentry, MAY_RMDIR);
3041 }
3042
selinux_inode_mknod(struct inode * dir,struct dentry * dentry,umode_t mode,dev_t dev)3043 static 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
selinux_inode_rename(struct inode * old_inode,struct dentry * old_dentry,struct inode * new_inode,struct dentry * new_dentry)3048 static 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
selinux_inode_readlink(struct dentry * dentry)3054 static 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
selinux_inode_follow_link(struct dentry * dentry,struct inode * inode,bool rcu)3061 static 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
audit_inode_permission(struct inode * inode,u32 perms,u32 audited,u32 denied,int result)3077 static 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
selinux_inode_permission(struct inode * inode,int mask)3091 static 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
selinux_inode_setattr(struct mnt_idmap * idmap,struct dentry * dentry,struct iattr * iattr)3132 static 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
selinux_inode_getattr(const struct path * path)3161 static int selinux_inode_getattr(const struct path *path)
3162 {
3163 return path_has_perm(current_cred(), path, FILE__GETATTR);
3164 }
3165
has_cap_mac_admin(bool audit)3166 static 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 */
selinux_inode_xattr_skipcap(const char * name)3189 static 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
selinux_inode_setxattr(struct mnt_idmap * idmap,struct dentry * dentry,const char * name,const void * value,size_t size,int flags)3195 static 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
selinux_inode_set_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name,struct posix_acl * kacl)3281 static 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
selinux_inode_get_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)3288 static 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
selinux_inode_remove_acl(struct mnt_idmap * idmap,struct dentry * dentry,const char * acl_name)3294 static 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
selinux_inode_post_setxattr(struct dentry * dentry,const char * name,const void * value,size_t size,int flags)3300 static 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
selinux_inode_getxattr(struct dentry * dentry,const char * name)3340 static 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
selinux_inode_listxattr(struct dentry * dentry)3347 static 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
selinux_inode_removexattr(struct mnt_idmap * idmap,struct dentry * dentry,const char * name)3354 static 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
selinux_path_notify(const struct path * path,u64 mask,unsigned int obj_type)3369 static 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_PRE_ACCESS |
3408 FS_CLOSE_NOWRITE))
3409 perm |= FILE__WATCH_READS;
3410
3411 return path_has_perm(current_cred(), path, perm);
3412 }
3413
3414 /*
3415 * Copy the inode security context value to the user.
3416 *
3417 * Permission check is handled by selinux_inode_getxattr hook.
3418 */
selinux_inode_getsecurity(struct mnt_idmap * idmap,struct inode * inode,const char * name,void ** buffer,bool alloc)3419 static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3420 struct inode *inode, const char *name,
3421 void **buffer, bool alloc)
3422 {
3423 u32 size;
3424 int error;
3425 char *context = NULL;
3426 struct inode_security_struct *isec;
3427
3428 /*
3429 * If we're not initialized yet, then we can't validate contexts, so
3430 * just let vfs_getxattr fall back to using the on-disk xattr.
3431 */
3432 if (!selinux_initialized() ||
3433 strcmp(name, XATTR_SELINUX_SUFFIX))
3434 return -EOPNOTSUPP;
3435
3436 /*
3437 * If the caller has CAP_MAC_ADMIN, then get the raw context
3438 * value even if it is not defined by current policy; otherwise,
3439 * use the in-core value under current policy.
3440 * Use the non-auditing forms of the permission checks since
3441 * getxattr may be called by unprivileged processes commonly
3442 * and lack of permission just means that we fall back to the
3443 * in-core context value, not a denial.
3444 */
3445 isec = inode_security(inode);
3446 if (has_cap_mac_admin(false))
3447 error = security_sid_to_context_force(isec->sid, &context,
3448 &size);
3449 else
3450 error = security_sid_to_context(isec->sid,
3451 &context, &size);
3452 if (error)
3453 return error;
3454 error = size;
3455 if (alloc) {
3456 *buffer = context;
3457 goto out_nofree;
3458 }
3459 kfree(context);
3460 out_nofree:
3461 return error;
3462 }
3463
selinux_inode_setsecurity(struct inode * inode,const char * name,const void * value,size_t size,int flags)3464 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3465 const void *value, size_t size, int flags)
3466 {
3467 struct inode_security_struct *isec = inode_security_novalidate(inode);
3468 struct superblock_security_struct *sbsec;
3469 u32 newsid;
3470 int rc;
3471
3472 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3473 return -EOPNOTSUPP;
3474
3475 sbsec = selinux_superblock(inode->i_sb);
3476 if (!(sbsec->flags & SBLABEL_MNT))
3477 return -EOPNOTSUPP;
3478
3479 if (!value || !size)
3480 return -EACCES;
3481
3482 rc = security_context_to_sid(value, size, &newsid,
3483 GFP_KERNEL);
3484 if (rc)
3485 return rc;
3486
3487 spin_lock(&isec->lock);
3488 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3489 isec->sid = newsid;
3490 isec->initialized = LABEL_INITIALIZED;
3491 spin_unlock(&isec->lock);
3492 return 0;
3493 }
3494
selinux_inode_listsecurity(struct inode * inode,char * buffer,size_t buffer_size)3495 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3496 {
3497 const int len = sizeof(XATTR_NAME_SELINUX);
3498
3499 if (!selinux_initialized())
3500 return 0;
3501
3502 if (buffer && len <= buffer_size)
3503 memcpy(buffer, XATTR_NAME_SELINUX, len);
3504 return len;
3505 }
3506
selinux_inode_getlsmprop(struct inode * inode,struct lsm_prop * prop)3507 static void selinux_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop)
3508 {
3509 struct inode_security_struct *isec = inode_security_novalidate(inode);
3510
3511 prop->selinux.secid = isec->sid;
3512 }
3513
selinux_inode_copy_up(struct dentry * src,struct cred ** new)3514 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3515 {
3516 struct lsm_prop prop;
3517 struct task_security_struct *tsec;
3518 struct cred *new_creds = *new;
3519
3520 if (new_creds == NULL) {
3521 new_creds = prepare_creds();
3522 if (!new_creds)
3523 return -ENOMEM;
3524 }
3525
3526 tsec = selinux_cred(new_creds);
3527 /* Get label from overlay inode and set it in create_sid */
3528 selinux_inode_getlsmprop(d_inode(src), &prop);
3529 tsec->create_sid = prop.selinux.secid;
3530 *new = new_creds;
3531 return 0;
3532 }
3533
selinux_inode_copy_up_xattr(struct dentry * dentry,const char * name)3534 static int selinux_inode_copy_up_xattr(struct dentry *dentry, const char *name)
3535 {
3536 /* The copy_up hook above sets the initial context on an inode, but we
3537 * don't then want to overwrite it by blindly copying all the lower
3538 * xattrs up. Instead, filter out SELinux-related xattrs following
3539 * policy load.
3540 */
3541 if (selinux_initialized() && !strcmp(name, XATTR_NAME_SELINUX))
3542 return -ECANCELED; /* Discard */
3543 /*
3544 * Any other attribute apart from SELINUX is not claimed, supported
3545 * by selinux.
3546 */
3547 return -EOPNOTSUPP;
3548 }
3549
3550 /* kernfs node operations */
3551
selinux_kernfs_init_security(struct kernfs_node * kn_dir,struct kernfs_node * kn)3552 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3553 struct kernfs_node *kn)
3554 {
3555 const struct task_security_struct *tsec = selinux_cred(current_cred());
3556 u32 parent_sid, newsid, clen;
3557 int rc;
3558 char *context;
3559
3560 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3561 if (rc == -ENODATA)
3562 return 0;
3563 else if (rc < 0)
3564 return rc;
3565
3566 clen = (u32)rc;
3567 context = kmalloc(clen, GFP_KERNEL);
3568 if (!context)
3569 return -ENOMEM;
3570
3571 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3572 if (rc < 0) {
3573 kfree(context);
3574 return rc;
3575 }
3576
3577 rc = security_context_to_sid(context, clen, &parent_sid,
3578 GFP_KERNEL);
3579 kfree(context);
3580 if (rc)
3581 return rc;
3582
3583 if (tsec->create_sid) {
3584 newsid = tsec->create_sid;
3585 } else {
3586 u16 secclass = inode_mode_to_security_class(kn->mode);
3587 struct qstr q;
3588
3589 q.name = kn->name;
3590 q.hash_len = hashlen_string(kn_dir, kn->name);
3591
3592 rc = security_transition_sid(tsec->sid,
3593 parent_sid, secclass, &q,
3594 &newsid);
3595 if (rc)
3596 return rc;
3597 }
3598
3599 rc = security_sid_to_context_force(newsid,
3600 &context, &clen);
3601 if (rc)
3602 return rc;
3603
3604 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3605 XATTR_CREATE);
3606 kfree(context);
3607 return rc;
3608 }
3609
3610
3611 /* file security operations */
3612
selinux_revalidate_file_permission(struct file * file,int mask)3613 static int selinux_revalidate_file_permission(struct file *file, int mask)
3614 {
3615 const struct cred *cred = current_cred();
3616 struct inode *inode = file_inode(file);
3617
3618 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3619 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3620 mask |= MAY_APPEND;
3621
3622 return file_has_perm(cred, file,
3623 file_mask_to_av(inode->i_mode, mask));
3624 }
3625
selinux_file_permission(struct file * file,int mask)3626 static int selinux_file_permission(struct file *file, int mask)
3627 {
3628 struct inode *inode = file_inode(file);
3629 struct file_security_struct *fsec = selinux_file(file);
3630 struct inode_security_struct *isec;
3631 u32 sid = current_sid();
3632
3633 if (!mask)
3634 /* No permission to check. Existence test. */
3635 return 0;
3636
3637 isec = inode_security(inode);
3638 if (sid == fsec->sid && fsec->isid == isec->sid &&
3639 fsec->pseqno == avc_policy_seqno())
3640 /* No change since file_open check. */
3641 return 0;
3642
3643 return selinux_revalidate_file_permission(file, mask);
3644 }
3645
selinux_file_alloc_security(struct file * file)3646 static int selinux_file_alloc_security(struct file *file)
3647 {
3648 struct file_security_struct *fsec = selinux_file(file);
3649 u32 sid = current_sid();
3650
3651 fsec->sid = sid;
3652 fsec->fown_sid = sid;
3653
3654 return 0;
3655 }
3656
3657 /*
3658 * Check whether a task has the ioctl permission and cmd
3659 * operation to an inode.
3660 */
ioctl_has_perm(const struct cred * cred,struct file * file,u32 requested,u16 cmd)3661 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3662 u32 requested, u16 cmd)
3663 {
3664 struct common_audit_data ad;
3665 struct file_security_struct *fsec = selinux_file(file);
3666 struct inode *inode = file_inode(file);
3667 struct inode_security_struct *isec;
3668 struct lsm_ioctlop_audit ioctl;
3669 u32 ssid = cred_sid(cred);
3670 int rc;
3671 u8 driver = cmd >> 8;
3672 u8 xperm = cmd & 0xff;
3673
3674 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3675 ad.u.op = &ioctl;
3676 ad.u.op->cmd = cmd;
3677 ad.u.op->path = file->f_path;
3678
3679 if (ssid != fsec->sid) {
3680 rc = avc_has_perm(ssid, fsec->sid,
3681 SECCLASS_FD,
3682 FD__USE,
3683 &ad);
3684 if (rc)
3685 goto out;
3686 }
3687
3688 if (unlikely(IS_PRIVATE(inode)))
3689 return 0;
3690
3691 isec = inode_security(inode);
3692 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, requested,
3693 driver, AVC_EXT_IOCTL, xperm, &ad);
3694 out:
3695 return rc;
3696 }
3697
selinux_file_ioctl(struct file * file,unsigned int cmd,unsigned long arg)3698 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3699 unsigned long arg)
3700 {
3701 const struct cred *cred = current_cred();
3702 int error = 0;
3703
3704 switch (cmd) {
3705 case FIONREAD:
3706 case FIBMAP:
3707 case FIGETBSZ:
3708 case FS_IOC_GETFLAGS:
3709 case FS_IOC_GETVERSION:
3710 error = file_has_perm(cred, file, FILE__GETATTR);
3711 break;
3712
3713 case FS_IOC_SETFLAGS:
3714 case FS_IOC_SETVERSION:
3715 error = file_has_perm(cred, file, FILE__SETATTR);
3716 break;
3717
3718 /* sys_ioctl() checks */
3719 case FIONBIO:
3720 case FIOASYNC:
3721 error = file_has_perm(cred, file, 0);
3722 break;
3723
3724 case KDSKBENT:
3725 case KDSKBSENT:
3726 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3727 CAP_OPT_NONE, true);
3728 break;
3729
3730 case FIOCLEX:
3731 case FIONCLEX:
3732 if (!selinux_policycap_ioctl_skip_cloexec())
3733 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3734 break;
3735
3736 /* default case assumes that the command will go
3737 * to the file's ioctl() function.
3738 */
3739 default:
3740 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3741 }
3742 return error;
3743 }
3744
selinux_file_ioctl_compat(struct file * file,unsigned int cmd,unsigned long arg)3745 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd,
3746 unsigned long arg)
3747 {
3748 /*
3749 * If we are in a 64-bit kernel running 32-bit userspace, we need to
3750 * make sure we don't compare 32-bit flags to 64-bit flags.
3751 */
3752 switch (cmd) {
3753 case FS_IOC32_GETFLAGS:
3754 cmd = FS_IOC_GETFLAGS;
3755 break;
3756 case FS_IOC32_SETFLAGS:
3757 cmd = FS_IOC_SETFLAGS;
3758 break;
3759 case FS_IOC32_GETVERSION:
3760 cmd = FS_IOC_GETVERSION;
3761 break;
3762 case FS_IOC32_SETVERSION:
3763 cmd = FS_IOC_SETVERSION;
3764 break;
3765 default:
3766 break;
3767 }
3768
3769 return selinux_file_ioctl(file, cmd, arg);
3770 }
3771
3772 static int default_noexec __ro_after_init;
3773
file_map_prot_check(struct file * file,unsigned long prot,int shared)3774 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3775 {
3776 const struct cred *cred = current_cred();
3777 u32 sid = cred_sid(cred);
3778 int rc = 0;
3779
3780 if (default_noexec &&
3781 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3782 (!shared && (prot & PROT_WRITE)))) {
3783 /*
3784 * We are making executable an anonymous mapping or a
3785 * private file mapping that will also be writable.
3786 * This has an additional check.
3787 */
3788 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3789 PROCESS__EXECMEM, NULL);
3790 if (rc)
3791 goto error;
3792 }
3793
3794 if (file) {
3795 /* read access is always possible with a mapping */
3796 u32 av = FILE__READ;
3797
3798 /* write access only matters if the mapping is shared */
3799 if (shared && (prot & PROT_WRITE))
3800 av |= FILE__WRITE;
3801
3802 if (prot & PROT_EXEC)
3803 av |= FILE__EXECUTE;
3804
3805 return file_has_perm(cred, file, av);
3806 }
3807
3808 error:
3809 return rc;
3810 }
3811
selinux_mmap_addr(unsigned long addr)3812 static int selinux_mmap_addr(unsigned long addr)
3813 {
3814 int rc = 0;
3815
3816 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3817 u32 sid = current_sid();
3818 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3819 MEMPROTECT__MMAP_ZERO, NULL);
3820 }
3821
3822 return rc;
3823 }
3824
selinux_mmap_file(struct file * file,unsigned long reqprot __always_unused,unsigned long prot,unsigned long flags)3825 static int selinux_mmap_file(struct file *file,
3826 unsigned long reqprot __always_unused,
3827 unsigned long prot, unsigned long flags)
3828 {
3829 struct common_audit_data ad;
3830 int rc;
3831
3832 if (file) {
3833 ad.type = LSM_AUDIT_DATA_FILE;
3834 ad.u.file = file;
3835 rc = inode_has_perm(current_cred(), file_inode(file),
3836 FILE__MAP, &ad);
3837 if (rc)
3838 return rc;
3839 }
3840
3841 return file_map_prot_check(file, prot,
3842 (flags & MAP_TYPE) == MAP_SHARED);
3843 }
3844
selinux_file_mprotect(struct vm_area_struct * vma,unsigned long reqprot __always_unused,unsigned long prot)3845 static int selinux_file_mprotect(struct vm_area_struct *vma,
3846 unsigned long reqprot __always_unused,
3847 unsigned long prot)
3848 {
3849 const struct cred *cred = current_cred();
3850 u32 sid = cred_sid(cred);
3851
3852 if (default_noexec &&
3853 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3854 int rc = 0;
3855 /*
3856 * We don't use the vma_is_initial_heap() helper as it has
3857 * a history of problems and is currently broken on systems
3858 * where there is no heap, e.g. brk == start_brk. Before
3859 * replacing the conditional below with vma_is_initial_heap(),
3860 * or something similar, please ensure that the logic is the
3861 * same as what we have below or you have tested every possible
3862 * corner case you can think to test.
3863 */
3864 if (vma->vm_start >= vma->vm_mm->start_brk &&
3865 vma->vm_end <= vma->vm_mm->brk) {
3866 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3867 PROCESS__EXECHEAP, NULL);
3868 } else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
3869 vma_is_stack_for_current(vma))) {
3870 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3871 PROCESS__EXECSTACK, NULL);
3872 } else if (vma->vm_file && vma->anon_vma) {
3873 /*
3874 * We are making executable a file mapping that has
3875 * had some COW done. Since pages might have been
3876 * written, check ability to execute the possibly
3877 * modified content. This typically should only
3878 * occur for text relocations.
3879 */
3880 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3881 }
3882 if (rc)
3883 return rc;
3884 }
3885
3886 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3887 }
3888
selinux_file_lock(struct file * file,unsigned int cmd)3889 static int selinux_file_lock(struct file *file, unsigned int cmd)
3890 {
3891 const struct cred *cred = current_cred();
3892
3893 return file_has_perm(cred, file, FILE__LOCK);
3894 }
3895
selinux_file_fcntl(struct file * file,unsigned int cmd,unsigned long arg)3896 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3897 unsigned long arg)
3898 {
3899 const struct cred *cred = current_cred();
3900 int err = 0;
3901
3902 switch (cmd) {
3903 case F_SETFL:
3904 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3905 err = file_has_perm(cred, file, FILE__WRITE);
3906 break;
3907 }
3908 fallthrough;
3909 case F_SETOWN:
3910 case F_SETSIG:
3911 case F_GETFL:
3912 case F_GETOWN:
3913 case F_GETSIG:
3914 case F_GETOWNER_UIDS:
3915 /* Just check FD__USE permission */
3916 err = file_has_perm(cred, file, 0);
3917 break;
3918 case F_GETLK:
3919 case F_SETLK:
3920 case F_SETLKW:
3921 case F_OFD_GETLK:
3922 case F_OFD_SETLK:
3923 case F_OFD_SETLKW:
3924 #if BITS_PER_LONG == 32
3925 case F_GETLK64:
3926 case F_SETLK64:
3927 case F_SETLKW64:
3928 #endif
3929 err = file_has_perm(cred, file, FILE__LOCK);
3930 break;
3931 }
3932
3933 return err;
3934 }
3935
selinux_file_set_fowner(struct file * file)3936 static void selinux_file_set_fowner(struct file *file)
3937 {
3938 struct file_security_struct *fsec;
3939
3940 fsec = selinux_file(file);
3941 fsec->fown_sid = current_sid();
3942 }
3943
selinux_file_send_sigiotask(struct task_struct * tsk,struct fown_struct * fown,int signum)3944 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3945 struct fown_struct *fown, int signum)
3946 {
3947 struct file *file;
3948 u32 sid = task_sid_obj(tsk);
3949 u32 perm;
3950 struct file_security_struct *fsec;
3951
3952 /* struct fown_struct is never outside the context of a struct file */
3953 file = fown->file;
3954
3955 fsec = selinux_file(file);
3956
3957 if (!signum)
3958 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3959 else
3960 perm = signal_to_av(signum);
3961
3962 return avc_has_perm(fsec->fown_sid, sid,
3963 SECCLASS_PROCESS, perm, NULL);
3964 }
3965
selinux_file_receive(struct file * file)3966 static int selinux_file_receive(struct file *file)
3967 {
3968 const struct cred *cred = current_cred();
3969
3970 return file_has_perm(cred, file, file_to_av(file));
3971 }
3972
selinux_file_open(struct file * file)3973 static int selinux_file_open(struct file *file)
3974 {
3975 struct file_security_struct *fsec;
3976 struct inode_security_struct *isec;
3977
3978 fsec = selinux_file(file);
3979 isec = inode_security(file_inode(file));
3980 /*
3981 * Save inode label and policy sequence number
3982 * at open-time so that selinux_file_permission
3983 * can determine whether revalidation is necessary.
3984 * Task label is already saved in the file security
3985 * struct as its SID.
3986 */
3987 fsec->isid = isec->sid;
3988 fsec->pseqno = avc_policy_seqno();
3989 /*
3990 * Since the inode label or policy seqno may have changed
3991 * between the selinux_inode_permission check and the saving
3992 * of state above, recheck that access is still permitted.
3993 * Otherwise, access might never be revalidated against the
3994 * new inode label or new policy.
3995 * This check is not redundant - do not remove.
3996 */
3997 return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3998 }
3999
4000 /* task security operations */
4001
selinux_task_alloc(struct task_struct * task,unsigned long clone_flags)4002 static int selinux_task_alloc(struct task_struct *task,
4003 unsigned long clone_flags)
4004 {
4005 u32 sid = current_sid();
4006
4007 return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
4008 }
4009
4010 /*
4011 * prepare a new set of credentials for modification
4012 */
selinux_cred_prepare(struct cred * new,const struct cred * old,gfp_t gfp)4013 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
4014 gfp_t gfp)
4015 {
4016 const struct task_security_struct *old_tsec = selinux_cred(old);
4017 struct task_security_struct *tsec = selinux_cred(new);
4018
4019 *tsec = *old_tsec;
4020 return 0;
4021 }
4022
4023 /*
4024 * transfer the SELinux data to a blank set of creds
4025 */
selinux_cred_transfer(struct cred * new,const struct cred * old)4026 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4027 {
4028 const struct task_security_struct *old_tsec = selinux_cred(old);
4029 struct task_security_struct *tsec = selinux_cred(new);
4030
4031 *tsec = *old_tsec;
4032 }
4033
selinux_cred_getsecid(const struct cred * c,u32 * secid)4034 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4035 {
4036 *secid = cred_sid(c);
4037 }
4038
selinux_cred_getlsmprop(const struct cred * c,struct lsm_prop * prop)4039 static void selinux_cred_getlsmprop(const struct cred *c, struct lsm_prop *prop)
4040 {
4041 prop->selinux.secid = cred_sid(c);
4042 }
4043
4044 /*
4045 * set the security data for a kernel service
4046 * - all the creation contexts are set to unlabelled
4047 */
selinux_kernel_act_as(struct cred * new,u32 secid)4048 static int selinux_kernel_act_as(struct cred *new, u32 secid)
4049 {
4050 struct task_security_struct *tsec = selinux_cred(new);
4051 u32 sid = current_sid();
4052 int ret;
4053
4054 ret = avc_has_perm(sid, secid,
4055 SECCLASS_KERNEL_SERVICE,
4056 KERNEL_SERVICE__USE_AS_OVERRIDE,
4057 NULL);
4058 if (ret == 0) {
4059 tsec->sid = secid;
4060 tsec->create_sid = 0;
4061 tsec->keycreate_sid = 0;
4062 tsec->sockcreate_sid = 0;
4063 }
4064 return ret;
4065 }
4066
4067 /*
4068 * set the file creation context in a security record to the same as the
4069 * objective context of the specified inode
4070 */
selinux_kernel_create_files_as(struct cred * new,struct inode * inode)4071 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4072 {
4073 struct inode_security_struct *isec = inode_security(inode);
4074 struct task_security_struct *tsec = selinux_cred(new);
4075 u32 sid = current_sid();
4076 int ret;
4077
4078 ret = avc_has_perm(sid, isec->sid,
4079 SECCLASS_KERNEL_SERVICE,
4080 KERNEL_SERVICE__CREATE_FILES_AS,
4081 NULL);
4082
4083 if (ret == 0)
4084 tsec->create_sid = isec->sid;
4085 return ret;
4086 }
4087
selinux_kernel_module_request(char * kmod_name)4088 static int selinux_kernel_module_request(char *kmod_name)
4089 {
4090 struct common_audit_data ad;
4091
4092 ad.type = LSM_AUDIT_DATA_KMOD;
4093 ad.u.kmod_name = kmod_name;
4094
4095 return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4096 SYSTEM__MODULE_REQUEST, &ad);
4097 }
4098
selinux_kernel_module_from_file(struct file * file)4099 static int selinux_kernel_module_from_file(struct file *file)
4100 {
4101 struct common_audit_data ad;
4102 struct inode_security_struct *isec;
4103 struct file_security_struct *fsec;
4104 u32 sid = current_sid();
4105 int rc;
4106
4107 /* init_module */
4108 if (file == NULL)
4109 return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
4110 SYSTEM__MODULE_LOAD, NULL);
4111
4112 /* finit_module */
4113
4114 ad.type = LSM_AUDIT_DATA_FILE;
4115 ad.u.file = file;
4116
4117 fsec = selinux_file(file);
4118 if (sid != fsec->sid) {
4119 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4120 if (rc)
4121 return rc;
4122 }
4123
4124 isec = inode_security(file_inode(file));
4125 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
4126 SYSTEM__MODULE_LOAD, &ad);
4127 }
4128
selinux_kernel_read_file(struct file * file,enum kernel_read_file_id id,bool contents)4129 static int selinux_kernel_read_file(struct file *file,
4130 enum kernel_read_file_id id,
4131 bool contents)
4132 {
4133 int rc = 0;
4134
4135 switch (id) {
4136 case READING_MODULE:
4137 rc = selinux_kernel_module_from_file(contents ? file : NULL);
4138 break;
4139 default:
4140 break;
4141 }
4142
4143 return rc;
4144 }
4145
selinux_kernel_load_data(enum kernel_load_data_id id,bool contents)4146 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4147 {
4148 int rc = 0;
4149
4150 switch (id) {
4151 case LOADING_MODULE:
4152 rc = selinux_kernel_module_from_file(NULL);
4153 break;
4154 default:
4155 break;
4156 }
4157
4158 return rc;
4159 }
4160
selinux_task_setpgid(struct task_struct * p,pid_t pgid)4161 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4162 {
4163 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4164 PROCESS__SETPGID, NULL);
4165 }
4166
selinux_task_getpgid(struct task_struct * p)4167 static int selinux_task_getpgid(struct task_struct *p)
4168 {
4169 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4170 PROCESS__GETPGID, NULL);
4171 }
4172
selinux_task_getsid(struct task_struct * p)4173 static int selinux_task_getsid(struct task_struct *p)
4174 {
4175 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4176 PROCESS__GETSESSION, NULL);
4177 }
4178
selinux_current_getlsmprop_subj(struct lsm_prop * prop)4179 static void selinux_current_getlsmprop_subj(struct lsm_prop *prop)
4180 {
4181 prop->selinux.secid = current_sid();
4182 }
4183
selinux_task_getlsmprop_obj(struct task_struct * p,struct lsm_prop * prop)4184 static void selinux_task_getlsmprop_obj(struct task_struct *p,
4185 struct lsm_prop *prop)
4186 {
4187 prop->selinux.secid = task_sid_obj(p);
4188 }
4189
selinux_task_setnice(struct task_struct * p,int nice)4190 static int selinux_task_setnice(struct task_struct *p, int nice)
4191 {
4192 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4193 PROCESS__SETSCHED, NULL);
4194 }
4195
selinux_task_setioprio(struct task_struct * p,int ioprio)4196 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4197 {
4198 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4199 PROCESS__SETSCHED, NULL);
4200 }
4201
selinux_task_getioprio(struct task_struct * p)4202 static int selinux_task_getioprio(struct task_struct *p)
4203 {
4204 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4205 PROCESS__GETSCHED, NULL);
4206 }
4207
selinux_task_prlimit(const struct cred * cred,const struct cred * tcred,unsigned int flags)4208 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4209 unsigned int flags)
4210 {
4211 u32 av = 0;
4212
4213 if (!flags)
4214 return 0;
4215 if (flags & LSM_PRLIMIT_WRITE)
4216 av |= PROCESS__SETRLIMIT;
4217 if (flags & LSM_PRLIMIT_READ)
4218 av |= PROCESS__GETRLIMIT;
4219 return avc_has_perm(cred_sid(cred), cred_sid(tcred),
4220 SECCLASS_PROCESS, av, NULL);
4221 }
4222
selinux_task_setrlimit(struct task_struct * p,unsigned int resource,struct rlimit * new_rlim)4223 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4224 struct rlimit *new_rlim)
4225 {
4226 struct rlimit *old_rlim = p->signal->rlim + resource;
4227
4228 /* Control the ability to change the hard limit (whether
4229 lowering or raising it), so that the hard limit can
4230 later be used as a safe reset point for the soft limit
4231 upon context transitions. See selinux_bprm_committing_creds. */
4232 if (old_rlim->rlim_max != new_rlim->rlim_max)
4233 return avc_has_perm(current_sid(), task_sid_obj(p),
4234 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4235
4236 return 0;
4237 }
4238
selinux_task_setscheduler(struct task_struct * p)4239 static int selinux_task_setscheduler(struct task_struct *p)
4240 {
4241 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4242 PROCESS__SETSCHED, NULL);
4243 }
4244
selinux_task_getscheduler(struct task_struct * p)4245 static int selinux_task_getscheduler(struct task_struct *p)
4246 {
4247 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4248 PROCESS__GETSCHED, NULL);
4249 }
4250
selinux_task_movememory(struct task_struct * p)4251 static int selinux_task_movememory(struct task_struct *p)
4252 {
4253 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4254 PROCESS__SETSCHED, NULL);
4255 }
4256
selinux_task_kill(struct task_struct * p,struct kernel_siginfo * info,int sig,const struct cred * cred)4257 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4258 int sig, const struct cred *cred)
4259 {
4260 u32 secid;
4261 u32 perm;
4262
4263 if (!sig)
4264 perm = PROCESS__SIGNULL; /* null signal; existence test */
4265 else
4266 perm = signal_to_av(sig);
4267 if (!cred)
4268 secid = current_sid();
4269 else
4270 secid = cred_sid(cred);
4271 return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4272 }
4273
selinux_task_to_inode(struct task_struct * p,struct inode * inode)4274 static void selinux_task_to_inode(struct task_struct *p,
4275 struct inode *inode)
4276 {
4277 struct inode_security_struct *isec = selinux_inode(inode);
4278 u32 sid = task_sid_obj(p);
4279
4280 spin_lock(&isec->lock);
4281 isec->sclass = inode_mode_to_security_class(inode->i_mode);
4282 isec->sid = sid;
4283 isec->initialized = LABEL_INITIALIZED;
4284 spin_unlock(&isec->lock);
4285 }
4286
selinux_userns_create(const struct cred * cred)4287 static int selinux_userns_create(const struct cred *cred)
4288 {
4289 u32 sid = current_sid();
4290
4291 return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4292 USER_NAMESPACE__CREATE, NULL);
4293 }
4294
4295 /* Returns error only if unable to parse addresses */
selinux_parse_skb_ipv4(struct sk_buff * skb,struct common_audit_data * ad,u8 * proto)4296 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4297 struct common_audit_data *ad, u8 *proto)
4298 {
4299 int offset, ihlen, ret = -EINVAL;
4300 struct iphdr _iph, *ih;
4301
4302 offset = skb_network_offset(skb);
4303 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4304 if (ih == NULL)
4305 goto out;
4306
4307 ihlen = ih->ihl * 4;
4308 if (ihlen < sizeof(_iph))
4309 goto out;
4310
4311 ad->u.net->v4info.saddr = ih->saddr;
4312 ad->u.net->v4info.daddr = ih->daddr;
4313 ret = 0;
4314
4315 if (proto)
4316 *proto = ih->protocol;
4317
4318 switch (ih->protocol) {
4319 case IPPROTO_TCP: {
4320 struct tcphdr _tcph, *th;
4321
4322 if (ntohs(ih->frag_off) & IP_OFFSET)
4323 break;
4324
4325 offset += ihlen;
4326 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4327 if (th == NULL)
4328 break;
4329
4330 ad->u.net->sport = th->source;
4331 ad->u.net->dport = th->dest;
4332 break;
4333 }
4334
4335 case IPPROTO_UDP: {
4336 struct udphdr _udph, *uh;
4337
4338 if (ntohs(ih->frag_off) & IP_OFFSET)
4339 break;
4340
4341 offset += ihlen;
4342 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4343 if (uh == NULL)
4344 break;
4345
4346 ad->u.net->sport = uh->source;
4347 ad->u.net->dport = uh->dest;
4348 break;
4349 }
4350
4351 case IPPROTO_DCCP: {
4352 struct dccp_hdr _dccph, *dh;
4353
4354 if (ntohs(ih->frag_off) & IP_OFFSET)
4355 break;
4356
4357 offset += ihlen;
4358 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4359 if (dh == NULL)
4360 break;
4361
4362 ad->u.net->sport = dh->dccph_sport;
4363 ad->u.net->dport = dh->dccph_dport;
4364 break;
4365 }
4366
4367 #if IS_ENABLED(CONFIG_IP_SCTP)
4368 case IPPROTO_SCTP: {
4369 struct sctphdr _sctph, *sh;
4370
4371 if (ntohs(ih->frag_off) & IP_OFFSET)
4372 break;
4373
4374 offset += ihlen;
4375 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4376 if (sh == NULL)
4377 break;
4378
4379 ad->u.net->sport = sh->source;
4380 ad->u.net->dport = sh->dest;
4381 break;
4382 }
4383 #endif
4384 default:
4385 break;
4386 }
4387 out:
4388 return ret;
4389 }
4390
4391 #if IS_ENABLED(CONFIG_IPV6)
4392
4393 /* Returns error only if unable to parse addresses */
selinux_parse_skb_ipv6(struct sk_buff * skb,struct common_audit_data * ad,u8 * proto)4394 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4395 struct common_audit_data *ad, u8 *proto)
4396 {
4397 u8 nexthdr;
4398 int ret = -EINVAL, offset;
4399 struct ipv6hdr _ipv6h, *ip6;
4400 __be16 frag_off;
4401
4402 offset = skb_network_offset(skb);
4403 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4404 if (ip6 == NULL)
4405 goto out;
4406
4407 ad->u.net->v6info.saddr = ip6->saddr;
4408 ad->u.net->v6info.daddr = ip6->daddr;
4409 ret = 0;
4410
4411 nexthdr = ip6->nexthdr;
4412 offset += sizeof(_ipv6h);
4413 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4414 if (offset < 0)
4415 goto out;
4416
4417 if (proto)
4418 *proto = nexthdr;
4419
4420 switch (nexthdr) {
4421 case IPPROTO_TCP: {
4422 struct tcphdr _tcph, *th;
4423
4424 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4425 if (th == NULL)
4426 break;
4427
4428 ad->u.net->sport = th->source;
4429 ad->u.net->dport = th->dest;
4430 break;
4431 }
4432
4433 case IPPROTO_UDP: {
4434 struct udphdr _udph, *uh;
4435
4436 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4437 if (uh == NULL)
4438 break;
4439
4440 ad->u.net->sport = uh->source;
4441 ad->u.net->dport = uh->dest;
4442 break;
4443 }
4444
4445 case IPPROTO_DCCP: {
4446 struct dccp_hdr _dccph, *dh;
4447
4448 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4449 if (dh == NULL)
4450 break;
4451
4452 ad->u.net->sport = dh->dccph_sport;
4453 ad->u.net->dport = dh->dccph_dport;
4454 break;
4455 }
4456
4457 #if IS_ENABLED(CONFIG_IP_SCTP)
4458 case IPPROTO_SCTP: {
4459 struct sctphdr _sctph, *sh;
4460
4461 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4462 if (sh == NULL)
4463 break;
4464
4465 ad->u.net->sport = sh->source;
4466 ad->u.net->dport = sh->dest;
4467 break;
4468 }
4469 #endif
4470 /* includes fragments */
4471 default:
4472 break;
4473 }
4474 out:
4475 return ret;
4476 }
4477
4478 #endif /* IPV6 */
4479
selinux_parse_skb(struct sk_buff * skb,struct common_audit_data * ad,char ** _addrp,int src,u8 * proto)4480 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4481 char **_addrp, int src, u8 *proto)
4482 {
4483 char *addrp;
4484 int ret;
4485
4486 switch (ad->u.net->family) {
4487 case PF_INET:
4488 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4489 if (ret)
4490 goto parse_error;
4491 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4492 &ad->u.net->v4info.daddr);
4493 goto okay;
4494
4495 #if IS_ENABLED(CONFIG_IPV6)
4496 case PF_INET6:
4497 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4498 if (ret)
4499 goto parse_error;
4500 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4501 &ad->u.net->v6info.daddr);
4502 goto okay;
4503 #endif /* IPV6 */
4504 default:
4505 addrp = NULL;
4506 goto okay;
4507 }
4508
4509 parse_error:
4510 pr_warn(
4511 "SELinux: failure in selinux_parse_skb(),"
4512 " unable to parse packet\n");
4513 return ret;
4514
4515 okay:
4516 if (_addrp)
4517 *_addrp = addrp;
4518 return 0;
4519 }
4520
4521 /**
4522 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4523 * @skb: the packet
4524 * @family: protocol family
4525 * @sid: the packet's peer label SID
4526 *
4527 * Description:
4528 * Check the various different forms of network peer labeling and determine
4529 * the peer label/SID for the packet; most of the magic actually occurs in
4530 * the security server function security_net_peersid_cmp(). The function
4531 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4532 * or -EACCES if @sid is invalid due to inconsistencies with the different
4533 * peer labels.
4534 *
4535 */
selinux_skb_peerlbl_sid(struct sk_buff * skb,u16 family,u32 * sid)4536 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4537 {
4538 int err;
4539 u32 xfrm_sid;
4540 u32 nlbl_sid;
4541 u32 nlbl_type;
4542
4543 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4544 if (unlikely(err))
4545 return -EACCES;
4546 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4547 if (unlikely(err))
4548 return -EACCES;
4549
4550 err = security_net_peersid_resolve(nlbl_sid,
4551 nlbl_type, xfrm_sid, sid);
4552 if (unlikely(err)) {
4553 pr_warn(
4554 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4555 " unable to determine packet's peer label\n");
4556 return -EACCES;
4557 }
4558
4559 return 0;
4560 }
4561
4562 /**
4563 * selinux_conn_sid - Determine the child socket label for a connection
4564 * @sk_sid: the parent socket's SID
4565 * @skb_sid: the packet's SID
4566 * @conn_sid: the resulting connection SID
4567 *
4568 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4569 * combined with the MLS information from @skb_sid in order to create
4570 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy
4571 * of @sk_sid. Returns zero on success, negative values on failure.
4572 *
4573 */
selinux_conn_sid(u32 sk_sid,u32 skb_sid,u32 * conn_sid)4574 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4575 {
4576 int err = 0;
4577
4578 if (skb_sid != SECSID_NULL)
4579 err = security_sid_mls_copy(sk_sid, skb_sid,
4580 conn_sid);
4581 else
4582 *conn_sid = sk_sid;
4583
4584 return err;
4585 }
4586
4587 /* socket security operations */
4588
socket_sockcreate_sid(const struct task_security_struct * tsec,u16 secclass,u32 * socksid)4589 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4590 u16 secclass, u32 *socksid)
4591 {
4592 if (tsec->sockcreate_sid > SECSID_NULL) {
4593 *socksid = tsec->sockcreate_sid;
4594 return 0;
4595 }
4596
4597 return security_transition_sid(tsec->sid, tsec->sid,
4598 secclass, NULL, socksid);
4599 }
4600
sock_skip_has_perm(u32 sid)4601 static bool sock_skip_has_perm(u32 sid)
4602 {
4603 if (sid == SECINITSID_KERNEL)
4604 return true;
4605
4606 /*
4607 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
4608 * inherited the kernel context from early boot used to be skipped
4609 * here, so preserve that behavior unless the capability is set.
4610 *
4611 * By setting the capability the policy signals that it is ready
4612 * for this quirk to be fixed. Note that sockets created by a kernel
4613 * thread or a usermode helper executed without a transition will
4614 * still be skipped in this check regardless of the policycap
4615 * setting.
4616 */
4617 if (!selinux_policycap_userspace_initial_context() &&
4618 sid == SECINITSID_INIT)
4619 return true;
4620 return false;
4621 }
4622
4623
sock_has_perm(struct sock * sk,u32 perms)4624 static int sock_has_perm(struct sock *sk, u32 perms)
4625 {
4626 struct sk_security_struct *sksec = sk->sk_security;
4627 struct common_audit_data ad;
4628 struct lsm_network_audit net;
4629
4630 if (sock_skip_has_perm(sksec->sid))
4631 return 0;
4632
4633 ad_net_init_from_sk(&ad, &net, sk);
4634
4635 return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
4636 &ad);
4637 }
4638
selinux_socket_create(int family,int type,int protocol,int kern)4639 static int selinux_socket_create(int family, int type,
4640 int protocol, int kern)
4641 {
4642 const struct task_security_struct *tsec = selinux_cred(current_cred());
4643 u32 newsid;
4644 u16 secclass;
4645 int rc;
4646
4647 if (kern)
4648 return 0;
4649
4650 secclass = socket_type_to_security_class(family, type, protocol);
4651 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4652 if (rc)
4653 return rc;
4654
4655 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4656 }
4657
selinux_socket_post_create(struct socket * sock,int family,int type,int protocol,int kern)4658 static int selinux_socket_post_create(struct socket *sock, int family,
4659 int type, int protocol, int kern)
4660 {
4661 const struct task_security_struct *tsec = selinux_cred(current_cred());
4662 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4663 struct sk_security_struct *sksec;
4664 u16 sclass = socket_type_to_security_class(family, type, protocol);
4665 u32 sid = SECINITSID_KERNEL;
4666 int err = 0;
4667
4668 if (!kern) {
4669 err = socket_sockcreate_sid(tsec, sclass, &sid);
4670 if (err)
4671 return err;
4672 }
4673
4674 isec->sclass = sclass;
4675 isec->sid = sid;
4676 isec->initialized = LABEL_INITIALIZED;
4677
4678 if (sock->sk) {
4679 sksec = selinux_sock(sock->sk);
4680 sksec->sclass = sclass;
4681 sksec->sid = sid;
4682 /* Allows detection of the first association on this socket */
4683 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4684 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4685
4686 err = selinux_netlbl_socket_post_create(sock->sk, family);
4687 }
4688
4689 return err;
4690 }
4691
selinux_socket_socketpair(struct socket * socka,struct socket * sockb)4692 static int selinux_socket_socketpair(struct socket *socka,
4693 struct socket *sockb)
4694 {
4695 struct sk_security_struct *sksec_a = selinux_sock(socka->sk);
4696 struct sk_security_struct *sksec_b = selinux_sock(sockb->sk);
4697
4698 sksec_a->peer_sid = sksec_b->sid;
4699 sksec_b->peer_sid = sksec_a->sid;
4700
4701 return 0;
4702 }
4703
4704 /* Range of port numbers used to automatically bind.
4705 Need to determine whether we should perform a name_bind
4706 permission check between the socket and the port number. */
4707
selinux_socket_bind(struct socket * sock,struct sockaddr * address,int addrlen)4708 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4709 {
4710 struct sock *sk = sock->sk;
4711 struct sk_security_struct *sksec = selinux_sock(sk);
4712 u16 family;
4713 int err;
4714
4715 err = sock_has_perm(sk, SOCKET__BIND);
4716 if (err)
4717 goto out;
4718
4719 /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4720 family = sk->sk_family;
4721 if (family == PF_INET || family == PF_INET6) {
4722 char *addrp;
4723 struct common_audit_data ad;
4724 struct lsm_network_audit net = {0,};
4725 struct sockaddr_in *addr4 = NULL;
4726 struct sockaddr_in6 *addr6 = NULL;
4727 u16 family_sa;
4728 unsigned short snum;
4729 u32 sid, node_perm;
4730
4731 /*
4732 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4733 * that validates multiple binding addresses. Because of this
4734 * need to check address->sa_family as it is possible to have
4735 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4736 */
4737 if (addrlen < offsetofend(struct sockaddr, sa_family))
4738 return -EINVAL;
4739 family_sa = address->sa_family;
4740 switch (family_sa) {
4741 case AF_UNSPEC:
4742 case AF_INET:
4743 if (addrlen < sizeof(struct sockaddr_in))
4744 return -EINVAL;
4745 addr4 = (struct sockaddr_in *)address;
4746 if (family_sa == AF_UNSPEC) {
4747 if (family == PF_INET6) {
4748 /* Length check from inet6_bind_sk() */
4749 if (addrlen < SIN6_LEN_RFC2133)
4750 return -EINVAL;
4751 /* Family check from __inet6_bind() */
4752 goto err_af;
4753 }
4754 /* see __inet_bind(), we only want to allow
4755 * AF_UNSPEC if the address is INADDR_ANY
4756 */
4757 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4758 goto err_af;
4759 family_sa = AF_INET;
4760 }
4761 snum = ntohs(addr4->sin_port);
4762 addrp = (char *)&addr4->sin_addr.s_addr;
4763 break;
4764 case AF_INET6:
4765 if (addrlen < SIN6_LEN_RFC2133)
4766 return -EINVAL;
4767 addr6 = (struct sockaddr_in6 *)address;
4768 snum = ntohs(addr6->sin6_port);
4769 addrp = (char *)&addr6->sin6_addr.s6_addr;
4770 break;
4771 default:
4772 goto err_af;
4773 }
4774
4775 ad.type = LSM_AUDIT_DATA_NET;
4776 ad.u.net = &net;
4777 ad.u.net->sport = htons(snum);
4778 ad.u.net->family = family_sa;
4779
4780 if (snum) {
4781 int low, high;
4782
4783 inet_get_local_port_range(sock_net(sk), &low, &high);
4784
4785 if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4786 snum < low || snum > high) {
4787 err = sel_netport_sid(sk->sk_protocol,
4788 snum, &sid);
4789 if (err)
4790 goto out;
4791 err = avc_has_perm(sksec->sid, sid,
4792 sksec->sclass,
4793 SOCKET__NAME_BIND, &ad);
4794 if (err)
4795 goto out;
4796 }
4797 }
4798
4799 switch (sksec->sclass) {
4800 case SECCLASS_TCP_SOCKET:
4801 node_perm = TCP_SOCKET__NODE_BIND;
4802 break;
4803
4804 case SECCLASS_UDP_SOCKET:
4805 node_perm = UDP_SOCKET__NODE_BIND;
4806 break;
4807
4808 case SECCLASS_DCCP_SOCKET:
4809 node_perm = DCCP_SOCKET__NODE_BIND;
4810 break;
4811
4812 case SECCLASS_SCTP_SOCKET:
4813 node_perm = SCTP_SOCKET__NODE_BIND;
4814 break;
4815
4816 default:
4817 node_perm = RAWIP_SOCKET__NODE_BIND;
4818 break;
4819 }
4820
4821 err = sel_netnode_sid(addrp, family_sa, &sid);
4822 if (err)
4823 goto out;
4824
4825 if (family_sa == AF_INET)
4826 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4827 else
4828 ad.u.net->v6info.saddr = addr6->sin6_addr;
4829
4830 err = avc_has_perm(sksec->sid, sid,
4831 sksec->sclass, node_perm, &ad);
4832 if (err)
4833 goto out;
4834 }
4835 out:
4836 return err;
4837 err_af:
4838 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4839 if (sk->sk_protocol == IPPROTO_SCTP)
4840 return -EINVAL;
4841 return -EAFNOSUPPORT;
4842 }
4843
4844 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4845 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4846 */
selinux_socket_connect_helper(struct socket * sock,struct sockaddr * address,int addrlen)4847 static int selinux_socket_connect_helper(struct socket *sock,
4848 struct sockaddr *address, int addrlen)
4849 {
4850 struct sock *sk = sock->sk;
4851 struct sk_security_struct *sksec = selinux_sock(sk);
4852 int err;
4853
4854 err = sock_has_perm(sk, SOCKET__CONNECT);
4855 if (err)
4856 return err;
4857 if (addrlen < offsetofend(struct sockaddr, sa_family))
4858 return -EINVAL;
4859
4860 /* connect(AF_UNSPEC) has special handling, as it is a documented
4861 * way to disconnect the socket
4862 */
4863 if (address->sa_family == AF_UNSPEC)
4864 return 0;
4865
4866 /*
4867 * If a TCP, DCCP or SCTP socket, check name_connect permission
4868 * for the port.
4869 */
4870 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4871 sksec->sclass == SECCLASS_DCCP_SOCKET ||
4872 sksec->sclass == SECCLASS_SCTP_SOCKET) {
4873 struct common_audit_data ad;
4874 struct lsm_network_audit net = {0,};
4875 struct sockaddr_in *addr4 = NULL;
4876 struct sockaddr_in6 *addr6 = NULL;
4877 unsigned short snum;
4878 u32 sid, perm;
4879
4880 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4881 * that validates multiple connect addresses. Because of this
4882 * need to check address->sa_family as it is possible to have
4883 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4884 */
4885 switch (address->sa_family) {
4886 case AF_INET:
4887 addr4 = (struct sockaddr_in *)address;
4888 if (addrlen < sizeof(struct sockaddr_in))
4889 return -EINVAL;
4890 snum = ntohs(addr4->sin_port);
4891 break;
4892 case AF_INET6:
4893 addr6 = (struct sockaddr_in6 *)address;
4894 if (addrlen < SIN6_LEN_RFC2133)
4895 return -EINVAL;
4896 snum = ntohs(addr6->sin6_port);
4897 break;
4898 default:
4899 /* Note that SCTP services expect -EINVAL, whereas
4900 * others expect -EAFNOSUPPORT.
4901 */
4902 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4903 return -EINVAL;
4904 else
4905 return -EAFNOSUPPORT;
4906 }
4907
4908 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4909 if (err)
4910 return err;
4911
4912 switch (sksec->sclass) {
4913 case SECCLASS_TCP_SOCKET:
4914 perm = TCP_SOCKET__NAME_CONNECT;
4915 break;
4916 case SECCLASS_DCCP_SOCKET:
4917 perm = DCCP_SOCKET__NAME_CONNECT;
4918 break;
4919 case SECCLASS_SCTP_SOCKET:
4920 perm = SCTP_SOCKET__NAME_CONNECT;
4921 break;
4922 }
4923
4924 ad.type = LSM_AUDIT_DATA_NET;
4925 ad.u.net = &net;
4926 ad.u.net->dport = htons(snum);
4927 ad.u.net->family = address->sa_family;
4928 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4929 if (err)
4930 return err;
4931 }
4932
4933 return 0;
4934 }
4935
4936 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
selinux_socket_connect(struct socket * sock,struct sockaddr * address,int addrlen)4937 static int selinux_socket_connect(struct socket *sock,
4938 struct sockaddr *address, int addrlen)
4939 {
4940 int err;
4941 struct sock *sk = sock->sk;
4942
4943 err = selinux_socket_connect_helper(sock, address, addrlen);
4944 if (err)
4945 return err;
4946
4947 return selinux_netlbl_socket_connect(sk, address);
4948 }
4949
selinux_socket_listen(struct socket * sock,int backlog)4950 static int selinux_socket_listen(struct socket *sock, int backlog)
4951 {
4952 return sock_has_perm(sock->sk, SOCKET__LISTEN);
4953 }
4954
selinux_socket_accept(struct socket * sock,struct socket * newsock)4955 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4956 {
4957 int err;
4958 struct inode_security_struct *isec;
4959 struct inode_security_struct *newisec;
4960 u16 sclass;
4961 u32 sid;
4962
4963 err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4964 if (err)
4965 return err;
4966
4967 isec = inode_security_novalidate(SOCK_INODE(sock));
4968 spin_lock(&isec->lock);
4969 sclass = isec->sclass;
4970 sid = isec->sid;
4971 spin_unlock(&isec->lock);
4972
4973 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4974 newisec->sclass = sclass;
4975 newisec->sid = sid;
4976 newisec->initialized = LABEL_INITIALIZED;
4977
4978 return 0;
4979 }
4980
selinux_socket_sendmsg(struct socket * sock,struct msghdr * msg,int size)4981 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4982 int size)
4983 {
4984 return sock_has_perm(sock->sk, SOCKET__WRITE);
4985 }
4986
selinux_socket_recvmsg(struct socket * sock,struct msghdr * msg,int size,int flags)4987 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4988 int size, int flags)
4989 {
4990 return sock_has_perm(sock->sk, SOCKET__READ);
4991 }
4992
selinux_socket_getsockname(struct socket * sock)4993 static int selinux_socket_getsockname(struct socket *sock)
4994 {
4995 return sock_has_perm(sock->sk, SOCKET__GETATTR);
4996 }
4997
selinux_socket_getpeername(struct socket * sock)4998 static int selinux_socket_getpeername(struct socket *sock)
4999 {
5000 return sock_has_perm(sock->sk, SOCKET__GETATTR);
5001 }
5002
selinux_socket_setsockopt(struct socket * sock,int level,int optname)5003 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
5004 {
5005 int err;
5006
5007 err = sock_has_perm(sock->sk, SOCKET__SETOPT);
5008 if (err)
5009 return err;
5010
5011 return selinux_netlbl_socket_setsockopt(sock, level, optname);
5012 }
5013
selinux_socket_getsockopt(struct socket * sock,int level,int optname)5014 static int selinux_socket_getsockopt(struct socket *sock, int level,
5015 int optname)
5016 {
5017 return sock_has_perm(sock->sk, SOCKET__GETOPT);
5018 }
5019
selinux_socket_shutdown(struct socket * sock,int how)5020 static int selinux_socket_shutdown(struct socket *sock, int how)
5021 {
5022 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
5023 }
5024
selinux_socket_unix_stream_connect(struct sock * sock,struct sock * other,struct sock * newsk)5025 static int selinux_socket_unix_stream_connect(struct sock *sock,
5026 struct sock *other,
5027 struct sock *newsk)
5028 {
5029 struct sk_security_struct *sksec_sock = selinux_sock(sock);
5030 struct sk_security_struct *sksec_other = selinux_sock(other);
5031 struct sk_security_struct *sksec_new = selinux_sock(newsk);
5032 struct common_audit_data ad;
5033 struct lsm_network_audit net;
5034 int err;
5035
5036 ad_net_init_from_sk(&ad, &net, other);
5037
5038 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
5039 sksec_other->sclass,
5040 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5041 if (err)
5042 return err;
5043
5044 /* server child socket */
5045 sksec_new->peer_sid = sksec_sock->sid;
5046 err = security_sid_mls_copy(sksec_other->sid,
5047 sksec_sock->sid, &sksec_new->sid);
5048 if (err)
5049 return err;
5050
5051 /* connecting socket */
5052 sksec_sock->peer_sid = sksec_new->sid;
5053
5054 return 0;
5055 }
5056
selinux_socket_unix_may_send(struct socket * sock,struct socket * other)5057 static int selinux_socket_unix_may_send(struct socket *sock,
5058 struct socket *other)
5059 {
5060 struct sk_security_struct *ssec = selinux_sock(sock->sk);
5061 struct sk_security_struct *osec = selinux_sock(other->sk);
5062 struct common_audit_data ad;
5063 struct lsm_network_audit net;
5064
5065 ad_net_init_from_sk(&ad, &net, other->sk);
5066
5067 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5068 &ad);
5069 }
5070
selinux_inet_sys_rcv_skb(struct net * ns,int ifindex,char * addrp,u16 family,u32 peer_sid,struct common_audit_data * ad)5071 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5072 char *addrp, u16 family, u32 peer_sid,
5073 struct common_audit_data *ad)
5074 {
5075 int err;
5076 u32 if_sid;
5077 u32 node_sid;
5078
5079 err = sel_netif_sid(ns, ifindex, &if_sid);
5080 if (err)
5081 return err;
5082 err = avc_has_perm(peer_sid, if_sid,
5083 SECCLASS_NETIF, NETIF__INGRESS, ad);
5084 if (err)
5085 return err;
5086
5087 err = sel_netnode_sid(addrp, family, &node_sid);
5088 if (err)
5089 return err;
5090 return avc_has_perm(peer_sid, node_sid,
5091 SECCLASS_NODE, NODE__RECVFROM, ad);
5092 }
5093
selinux_sock_rcv_skb_compat(struct sock * sk,struct sk_buff * skb,u16 family)5094 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5095 u16 family)
5096 {
5097 int err = 0;
5098 struct sk_security_struct *sksec = selinux_sock(sk);
5099 u32 sk_sid = sksec->sid;
5100 struct common_audit_data ad;
5101 struct lsm_network_audit net;
5102 char *addrp;
5103
5104 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5105 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5106 if (err)
5107 return err;
5108
5109 if (selinux_secmark_enabled()) {
5110 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5111 PACKET__RECV, &ad);
5112 if (err)
5113 return err;
5114 }
5115
5116 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5117 if (err)
5118 return err;
5119 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5120
5121 return err;
5122 }
5123
selinux_socket_sock_rcv_skb(struct sock * sk,struct sk_buff * skb)5124 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5125 {
5126 int err, peerlbl_active, secmark_active;
5127 struct sk_security_struct *sksec = selinux_sock(sk);
5128 u16 family = sk->sk_family;
5129 u32 sk_sid = sksec->sid;
5130 struct common_audit_data ad;
5131 struct lsm_network_audit net;
5132 char *addrp;
5133
5134 if (family != PF_INET && family != PF_INET6)
5135 return 0;
5136
5137 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5138 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5139 family = PF_INET;
5140
5141 /* If any sort of compatibility mode is enabled then handoff processing
5142 * to the selinux_sock_rcv_skb_compat() function to deal with the
5143 * special handling. We do this in an attempt to keep this function
5144 * as fast and as clean as possible. */
5145 if (!selinux_policycap_netpeer())
5146 return selinux_sock_rcv_skb_compat(sk, skb, family);
5147
5148 secmark_active = selinux_secmark_enabled();
5149 peerlbl_active = selinux_peerlbl_enabled();
5150 if (!secmark_active && !peerlbl_active)
5151 return 0;
5152
5153 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5154 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5155 if (err)
5156 return err;
5157
5158 if (peerlbl_active) {
5159 u32 peer_sid;
5160
5161 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5162 if (err)
5163 return err;
5164 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5165 addrp, family, peer_sid, &ad);
5166 if (err) {
5167 selinux_netlbl_err(skb, family, err, 0);
5168 return err;
5169 }
5170 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
5171 PEER__RECV, &ad);
5172 if (err) {
5173 selinux_netlbl_err(skb, family, err, 0);
5174 return err;
5175 }
5176 }
5177
5178 if (secmark_active) {
5179 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5180 PACKET__RECV, &ad);
5181 if (err)
5182 return err;
5183 }
5184
5185 return err;
5186 }
5187
selinux_socket_getpeersec_stream(struct socket * sock,sockptr_t optval,sockptr_t optlen,unsigned int len)5188 static int selinux_socket_getpeersec_stream(struct socket *sock,
5189 sockptr_t optval, sockptr_t optlen,
5190 unsigned int len)
5191 {
5192 int err = 0;
5193 char *scontext = NULL;
5194 u32 scontext_len;
5195 struct sk_security_struct *sksec = selinux_sock(sock->sk);
5196 u32 peer_sid = SECSID_NULL;
5197
5198 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5199 sksec->sclass == SECCLASS_TCP_SOCKET ||
5200 sksec->sclass == SECCLASS_SCTP_SOCKET)
5201 peer_sid = sksec->peer_sid;
5202 if (peer_sid == SECSID_NULL)
5203 return -ENOPROTOOPT;
5204
5205 err = security_sid_to_context(peer_sid, &scontext,
5206 &scontext_len);
5207 if (err)
5208 return err;
5209 if (scontext_len > len) {
5210 err = -ERANGE;
5211 goto out_len;
5212 }
5213
5214 if (copy_to_sockptr(optval, scontext, scontext_len))
5215 err = -EFAULT;
5216 out_len:
5217 if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5218 err = -EFAULT;
5219 kfree(scontext);
5220 return err;
5221 }
5222
selinux_socket_getpeersec_dgram(struct socket * sock,struct sk_buff * skb,u32 * secid)5223 static int selinux_socket_getpeersec_dgram(struct socket *sock,
5224 struct sk_buff *skb, u32 *secid)
5225 {
5226 u32 peer_secid = SECSID_NULL;
5227 u16 family;
5228
5229 if (skb && skb->protocol == htons(ETH_P_IP))
5230 family = PF_INET;
5231 else if (skb && skb->protocol == htons(ETH_P_IPV6))
5232 family = PF_INET6;
5233 else if (sock)
5234 family = sock->sk->sk_family;
5235 else {
5236 *secid = SECSID_NULL;
5237 return -EINVAL;
5238 }
5239
5240 if (sock && family == PF_UNIX) {
5241 struct inode_security_struct *isec;
5242 isec = inode_security_novalidate(SOCK_INODE(sock));
5243 peer_secid = isec->sid;
5244 } else if (skb)
5245 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5246
5247 *secid = peer_secid;
5248 if (peer_secid == SECSID_NULL)
5249 return -ENOPROTOOPT;
5250 return 0;
5251 }
5252
selinux_sk_alloc_security(struct sock * sk,int family,gfp_t priority)5253 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5254 {
5255 struct sk_security_struct *sksec = selinux_sock(sk);
5256
5257 sksec->peer_sid = SECINITSID_UNLABELED;
5258 sksec->sid = SECINITSID_UNLABELED;
5259 sksec->sclass = SECCLASS_SOCKET;
5260 selinux_netlbl_sk_security_reset(sksec);
5261
5262 return 0;
5263 }
5264
selinux_sk_free_security(struct sock * sk)5265 static void selinux_sk_free_security(struct sock *sk)
5266 {
5267 struct sk_security_struct *sksec = selinux_sock(sk);
5268
5269 selinux_netlbl_sk_security_free(sksec);
5270 }
5271
selinux_sk_clone_security(const struct sock * sk,struct sock * newsk)5272 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5273 {
5274 struct sk_security_struct *sksec = selinux_sock(sk);
5275 struct sk_security_struct *newsksec = selinux_sock(newsk);
5276
5277 newsksec->sid = sksec->sid;
5278 newsksec->peer_sid = sksec->peer_sid;
5279 newsksec->sclass = sksec->sclass;
5280
5281 selinux_netlbl_sk_security_reset(newsksec);
5282 }
5283
selinux_sk_getsecid(const struct sock * sk,u32 * secid)5284 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid)
5285 {
5286 if (!sk)
5287 *secid = SECINITSID_ANY_SOCKET;
5288 else {
5289 const struct sk_security_struct *sksec = selinux_sock(sk);
5290
5291 *secid = sksec->sid;
5292 }
5293 }
5294
selinux_sock_graft(struct sock * sk,struct socket * parent)5295 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5296 {
5297 struct inode_security_struct *isec =
5298 inode_security_novalidate(SOCK_INODE(parent));
5299 struct sk_security_struct *sksec = selinux_sock(sk);
5300
5301 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5302 sk->sk_family == PF_UNIX)
5303 isec->sid = sksec->sid;
5304 sksec->sclass = isec->sclass;
5305 }
5306
5307 /*
5308 * Determines peer_secid for the asoc and updates socket's peer label
5309 * if it's the first association on the socket.
5310 */
selinux_sctp_process_new_assoc(struct sctp_association * asoc,struct sk_buff * skb)5311 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5312 struct sk_buff *skb)
5313 {
5314 struct sock *sk = asoc->base.sk;
5315 u16 family = sk->sk_family;
5316 struct sk_security_struct *sksec = selinux_sock(sk);
5317 struct common_audit_data ad;
5318 struct lsm_network_audit net;
5319 int err;
5320
5321 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5322 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5323 family = PF_INET;
5324
5325 if (selinux_peerlbl_enabled()) {
5326 asoc->peer_secid = SECSID_NULL;
5327
5328 /* This will return peer_sid = SECSID_NULL if there are
5329 * no peer labels, see security_net_peersid_resolve().
5330 */
5331 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5332 if (err)
5333 return err;
5334
5335 if (asoc->peer_secid == SECSID_NULL)
5336 asoc->peer_secid = SECINITSID_UNLABELED;
5337 } else {
5338 asoc->peer_secid = SECINITSID_UNLABELED;
5339 }
5340
5341 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5342 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5343
5344 /* Here as first association on socket. As the peer SID
5345 * was allowed by peer recv (and the netif/node checks),
5346 * then it is approved by policy and used as the primary
5347 * peer SID for getpeercon(3).
5348 */
5349 sksec->peer_sid = asoc->peer_secid;
5350 } else if (sksec->peer_sid != asoc->peer_secid) {
5351 /* Other association peer SIDs are checked to enforce
5352 * consistency among the peer SIDs.
5353 */
5354 ad_net_init_from_sk(&ad, &net, asoc->base.sk);
5355 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5356 sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5357 &ad);
5358 if (err)
5359 return err;
5360 }
5361 return 0;
5362 }
5363
5364 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5365 * happens on an incoming connect(2), sctp_connectx(3) or
5366 * sctp_sendmsg(3) (with no association already present).
5367 */
selinux_sctp_assoc_request(struct sctp_association * asoc,struct sk_buff * skb)5368 static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5369 struct sk_buff *skb)
5370 {
5371 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5372 u32 conn_sid;
5373 int err;
5374
5375 if (!selinux_policycap_extsockclass())
5376 return 0;
5377
5378 err = selinux_sctp_process_new_assoc(asoc, skb);
5379 if (err)
5380 return err;
5381
5382 /* Compute the MLS component for the connection and store
5383 * the information in asoc. This will be used by SCTP TCP type
5384 * sockets and peeled off connections as they cause a new
5385 * socket to be generated. selinux_sctp_sk_clone() will then
5386 * plug this into the new socket.
5387 */
5388 err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5389 if (err)
5390 return err;
5391
5392 asoc->secid = conn_sid;
5393
5394 /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5395 return selinux_netlbl_sctp_assoc_request(asoc, skb);
5396 }
5397
5398 /* Called when SCTP receives a COOKIE ACK chunk as the final
5399 * response to an association request (initited by us).
5400 */
selinux_sctp_assoc_established(struct sctp_association * asoc,struct sk_buff * skb)5401 static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5402 struct sk_buff *skb)
5403 {
5404 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5405
5406 if (!selinux_policycap_extsockclass())
5407 return 0;
5408
5409 /* Inherit secid from the parent socket - this will be picked up
5410 * by selinux_sctp_sk_clone() if the association gets peeled off
5411 * into a new socket.
5412 */
5413 asoc->secid = sksec->sid;
5414
5415 return selinux_sctp_process_new_assoc(asoc, skb);
5416 }
5417
5418 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5419 * based on their @optname.
5420 */
selinux_sctp_bind_connect(struct sock * sk,int optname,struct sockaddr * address,int addrlen)5421 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5422 struct sockaddr *address,
5423 int addrlen)
5424 {
5425 int len, err = 0, walk_size = 0;
5426 void *addr_buf;
5427 struct sockaddr *addr;
5428 struct socket *sock;
5429
5430 if (!selinux_policycap_extsockclass())
5431 return 0;
5432
5433 /* Process one or more addresses that may be IPv4 or IPv6 */
5434 sock = sk->sk_socket;
5435 addr_buf = address;
5436
5437 while (walk_size < addrlen) {
5438 if (walk_size + sizeof(sa_family_t) > addrlen)
5439 return -EINVAL;
5440
5441 addr = addr_buf;
5442 switch (addr->sa_family) {
5443 case AF_UNSPEC:
5444 case AF_INET:
5445 len = sizeof(struct sockaddr_in);
5446 break;
5447 case AF_INET6:
5448 len = sizeof(struct sockaddr_in6);
5449 break;
5450 default:
5451 return -EINVAL;
5452 }
5453
5454 if (walk_size + len > addrlen)
5455 return -EINVAL;
5456
5457 err = -EINVAL;
5458 switch (optname) {
5459 /* Bind checks */
5460 case SCTP_PRIMARY_ADDR:
5461 case SCTP_SET_PEER_PRIMARY_ADDR:
5462 case SCTP_SOCKOPT_BINDX_ADD:
5463 err = selinux_socket_bind(sock, addr, len);
5464 break;
5465 /* Connect checks */
5466 case SCTP_SOCKOPT_CONNECTX:
5467 case SCTP_PARAM_SET_PRIMARY:
5468 case SCTP_PARAM_ADD_IP:
5469 case SCTP_SENDMSG_CONNECT:
5470 err = selinux_socket_connect_helper(sock, addr, len);
5471 if (err)
5472 return err;
5473
5474 /* As selinux_sctp_bind_connect() is called by the
5475 * SCTP protocol layer, the socket is already locked,
5476 * therefore selinux_netlbl_socket_connect_locked()
5477 * is called here. The situations handled are:
5478 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5479 * whenever a new IP address is added or when a new
5480 * primary address is selected.
5481 * Note that an SCTP connect(2) call happens before
5482 * the SCTP protocol layer and is handled via
5483 * selinux_socket_connect().
5484 */
5485 err = selinux_netlbl_socket_connect_locked(sk, addr);
5486 break;
5487 }
5488
5489 if (err)
5490 return err;
5491
5492 addr_buf += len;
5493 walk_size += len;
5494 }
5495
5496 return 0;
5497 }
5498
5499 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
selinux_sctp_sk_clone(struct sctp_association * asoc,struct sock * sk,struct sock * newsk)5500 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5501 struct sock *newsk)
5502 {
5503 struct sk_security_struct *sksec = selinux_sock(sk);
5504 struct sk_security_struct *newsksec = selinux_sock(newsk);
5505
5506 /* If policy does not support SECCLASS_SCTP_SOCKET then call
5507 * the non-sctp clone version.
5508 */
5509 if (!selinux_policycap_extsockclass())
5510 return selinux_sk_clone_security(sk, newsk);
5511
5512 newsksec->sid = asoc->secid;
5513 newsksec->peer_sid = asoc->peer_secid;
5514 newsksec->sclass = sksec->sclass;
5515 selinux_netlbl_sctp_sk_clone(sk, newsk);
5516 }
5517
selinux_mptcp_add_subflow(struct sock * sk,struct sock * ssk)5518 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5519 {
5520 struct sk_security_struct *ssksec = selinux_sock(ssk);
5521 struct sk_security_struct *sksec = selinux_sock(sk);
5522
5523 ssksec->sclass = sksec->sclass;
5524 ssksec->sid = sksec->sid;
5525
5526 /* replace the existing subflow label deleting the existing one
5527 * and re-recreating a new label using the updated context
5528 */
5529 selinux_netlbl_sk_security_free(ssksec);
5530 return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5531 }
5532
selinux_inet_conn_request(const struct sock * sk,struct sk_buff * skb,struct request_sock * req)5533 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5534 struct request_sock *req)
5535 {
5536 struct sk_security_struct *sksec = selinux_sock(sk);
5537 int err;
5538 u16 family = req->rsk_ops->family;
5539 u32 connsid;
5540 u32 peersid;
5541
5542 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5543 if (err)
5544 return err;
5545 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5546 if (err)
5547 return err;
5548 req->secid = connsid;
5549 req->peer_secid = peersid;
5550
5551 return selinux_netlbl_inet_conn_request(req, family);
5552 }
5553
selinux_inet_csk_clone(struct sock * newsk,const struct request_sock * req)5554 static void selinux_inet_csk_clone(struct sock *newsk,
5555 const struct request_sock *req)
5556 {
5557 struct sk_security_struct *newsksec = selinux_sock(newsk);
5558
5559 newsksec->sid = req->secid;
5560 newsksec->peer_sid = req->peer_secid;
5561 /* NOTE: Ideally, we should also get the isec->sid for the
5562 new socket in sync, but we don't have the isec available yet.
5563 So we will wait until sock_graft to do it, by which
5564 time it will have been created and available. */
5565
5566 /* We don't need to take any sort of lock here as we are the only
5567 * thread with access to newsksec */
5568 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5569 }
5570
selinux_inet_conn_established(struct sock * sk,struct sk_buff * skb)5571 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5572 {
5573 u16 family = sk->sk_family;
5574 struct sk_security_struct *sksec = selinux_sock(sk);
5575
5576 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5577 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5578 family = PF_INET;
5579
5580 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5581 }
5582
selinux_secmark_relabel_packet(u32 sid)5583 static int selinux_secmark_relabel_packet(u32 sid)
5584 {
5585 return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO,
5586 NULL);
5587 }
5588
selinux_secmark_refcount_inc(void)5589 static void selinux_secmark_refcount_inc(void)
5590 {
5591 atomic_inc(&selinux_secmark_refcount);
5592 }
5593
selinux_secmark_refcount_dec(void)5594 static void selinux_secmark_refcount_dec(void)
5595 {
5596 atomic_dec(&selinux_secmark_refcount);
5597 }
5598
selinux_req_classify_flow(const struct request_sock * req,struct flowi_common * flic)5599 static void selinux_req_classify_flow(const struct request_sock *req,
5600 struct flowi_common *flic)
5601 {
5602 flic->flowic_secid = req->secid;
5603 }
5604
selinux_tun_dev_alloc_security(void * security)5605 static int selinux_tun_dev_alloc_security(void *security)
5606 {
5607 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5608
5609 tunsec->sid = current_sid();
5610 return 0;
5611 }
5612
selinux_tun_dev_create(void)5613 static int selinux_tun_dev_create(void)
5614 {
5615 u32 sid = current_sid();
5616
5617 /* we aren't taking into account the "sockcreate" SID since the socket
5618 * that is being created here is not a socket in the traditional sense,
5619 * instead it is a private sock, accessible only to the kernel, and
5620 * representing a wide range of network traffic spanning multiple
5621 * connections unlike traditional sockets - check the TUN driver to
5622 * get a better understanding of why this socket is special */
5623
5624 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5625 NULL);
5626 }
5627
selinux_tun_dev_attach_queue(void * security)5628 static int selinux_tun_dev_attach_queue(void *security)
5629 {
5630 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5631
5632 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5633 TUN_SOCKET__ATTACH_QUEUE, NULL);
5634 }
5635
selinux_tun_dev_attach(struct sock * sk,void * security)5636 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5637 {
5638 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5639 struct sk_security_struct *sksec = selinux_sock(sk);
5640
5641 /* we don't currently perform any NetLabel based labeling here and it
5642 * isn't clear that we would want to do so anyway; while we could apply
5643 * labeling without the support of the TUN user the resulting labeled
5644 * traffic from the other end of the connection would almost certainly
5645 * cause confusion to the TUN user that had no idea network labeling
5646 * protocols were being used */
5647
5648 sksec->sid = tunsec->sid;
5649 sksec->sclass = SECCLASS_TUN_SOCKET;
5650
5651 return 0;
5652 }
5653
selinux_tun_dev_open(void * security)5654 static int selinux_tun_dev_open(void *security)
5655 {
5656 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5657 u32 sid = current_sid();
5658 int err;
5659
5660 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5661 TUN_SOCKET__RELABELFROM, NULL);
5662 if (err)
5663 return err;
5664 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5665 TUN_SOCKET__RELABELTO, NULL);
5666 if (err)
5667 return err;
5668 tunsec->sid = sid;
5669
5670 return 0;
5671 }
5672
5673 #ifdef CONFIG_NETFILTER
5674
selinux_ip_forward(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)5675 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5676 const struct nf_hook_state *state)
5677 {
5678 int ifindex;
5679 u16 family;
5680 char *addrp;
5681 u32 peer_sid;
5682 struct common_audit_data ad;
5683 struct lsm_network_audit net;
5684 int secmark_active, peerlbl_active;
5685
5686 if (!selinux_policycap_netpeer())
5687 return NF_ACCEPT;
5688
5689 secmark_active = selinux_secmark_enabled();
5690 peerlbl_active = selinux_peerlbl_enabled();
5691 if (!secmark_active && !peerlbl_active)
5692 return NF_ACCEPT;
5693
5694 family = state->pf;
5695 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5696 return NF_DROP;
5697
5698 ifindex = state->in->ifindex;
5699 ad_net_init_from_iif(&ad, &net, ifindex, family);
5700 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5701 return NF_DROP;
5702
5703 if (peerlbl_active) {
5704 int err;
5705
5706 err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5707 addrp, family, peer_sid, &ad);
5708 if (err) {
5709 selinux_netlbl_err(skb, family, err, 1);
5710 return NF_DROP;
5711 }
5712 }
5713
5714 if (secmark_active)
5715 if (avc_has_perm(peer_sid, skb->secmark,
5716 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5717 return NF_DROP;
5718
5719 if (netlbl_enabled())
5720 /* we do this in the FORWARD path and not the POST_ROUTING
5721 * path because we want to make sure we apply the necessary
5722 * labeling before IPsec is applied so we can leverage AH
5723 * protection */
5724 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5725 return NF_DROP;
5726
5727 return NF_ACCEPT;
5728 }
5729
selinux_ip_output(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)5730 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5731 const struct nf_hook_state *state)
5732 {
5733 struct sock *sk;
5734 u32 sid;
5735
5736 if (!netlbl_enabled())
5737 return NF_ACCEPT;
5738
5739 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5740 * because we want to make sure we apply the necessary labeling
5741 * before IPsec is applied so we can leverage AH protection */
5742 sk = sk_to_full_sk(skb->sk);
5743 if (sk) {
5744 struct sk_security_struct *sksec;
5745
5746 if (sk_listener(sk))
5747 /* if the socket is the listening state then this
5748 * packet is a SYN-ACK packet which means it needs to
5749 * be labeled based on the connection/request_sock and
5750 * not the parent socket. unfortunately, we can't
5751 * lookup the request_sock yet as it isn't queued on
5752 * the parent socket until after the SYN-ACK is sent.
5753 * the "solution" is to simply pass the packet as-is
5754 * as any IP option based labeling should be copied
5755 * from the initial connection request (in the IP
5756 * layer). it is far from ideal, but until we get a
5757 * security label in the packet itself this is the
5758 * best we can do. */
5759 return NF_ACCEPT;
5760
5761 /* standard practice, label using the parent socket */
5762 sksec = selinux_sock(sk);
5763 sid = sksec->sid;
5764 } else
5765 sid = SECINITSID_KERNEL;
5766 if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5767 return NF_DROP;
5768
5769 return NF_ACCEPT;
5770 }
5771
5772
selinux_ip_postroute_compat(struct sk_buff * skb,const struct nf_hook_state * state)5773 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5774 const struct nf_hook_state *state)
5775 {
5776 struct sock *sk;
5777 struct sk_security_struct *sksec;
5778 struct common_audit_data ad;
5779 struct lsm_network_audit net;
5780 u8 proto = 0;
5781
5782 sk = skb_to_full_sk(skb);
5783 if (sk == NULL)
5784 return NF_ACCEPT;
5785 sksec = selinux_sock(sk);
5786
5787 ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf);
5788 if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5789 return NF_DROP;
5790
5791 if (selinux_secmark_enabled())
5792 if (avc_has_perm(sksec->sid, skb->secmark,
5793 SECCLASS_PACKET, PACKET__SEND, &ad))
5794 return NF_DROP_ERR(-ECONNREFUSED);
5795
5796 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5797 return NF_DROP_ERR(-ECONNREFUSED);
5798
5799 return NF_ACCEPT;
5800 }
5801
selinux_ip_postroute(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)5802 static unsigned int selinux_ip_postroute(void *priv,
5803 struct sk_buff *skb,
5804 const struct nf_hook_state *state)
5805 {
5806 u16 family;
5807 u32 secmark_perm;
5808 u32 peer_sid;
5809 int ifindex;
5810 struct sock *sk;
5811 struct common_audit_data ad;
5812 struct lsm_network_audit net;
5813 char *addrp;
5814 int secmark_active, peerlbl_active;
5815
5816 /* If any sort of compatibility mode is enabled then handoff processing
5817 * to the selinux_ip_postroute_compat() function to deal with the
5818 * special handling. We do this in an attempt to keep this function
5819 * as fast and as clean as possible. */
5820 if (!selinux_policycap_netpeer())
5821 return selinux_ip_postroute_compat(skb, state);
5822
5823 secmark_active = selinux_secmark_enabled();
5824 peerlbl_active = selinux_peerlbl_enabled();
5825 if (!secmark_active && !peerlbl_active)
5826 return NF_ACCEPT;
5827
5828 sk = skb_to_full_sk(skb);
5829
5830 #ifdef CONFIG_XFRM
5831 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5832 * packet transformation so allow the packet to pass without any checks
5833 * since we'll have another chance to perform access control checks
5834 * when the packet is on it's final way out.
5835 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5836 * is NULL, in this case go ahead and apply access control.
5837 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5838 * TCP listening state we cannot wait until the XFRM processing
5839 * is done as we will miss out on the SA label if we do;
5840 * unfortunately, this means more work, but it is only once per
5841 * connection. */
5842 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5843 !(sk && sk_listener(sk)))
5844 return NF_ACCEPT;
5845 #endif
5846
5847 family = state->pf;
5848 if (sk == NULL) {
5849 /* Without an associated socket the packet is either coming
5850 * from the kernel or it is being forwarded; check the packet
5851 * to determine which and if the packet is being forwarded
5852 * query the packet directly to determine the security label. */
5853 if (skb->skb_iif) {
5854 secmark_perm = PACKET__FORWARD_OUT;
5855 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5856 return NF_DROP;
5857 } else {
5858 secmark_perm = PACKET__SEND;
5859 peer_sid = SECINITSID_KERNEL;
5860 }
5861 } else if (sk_listener(sk)) {
5862 /* Locally generated packet but the associated socket is in the
5863 * listening state which means this is a SYN-ACK packet. In
5864 * this particular case the correct security label is assigned
5865 * to the connection/request_sock but unfortunately we can't
5866 * query the request_sock as it isn't queued on the parent
5867 * socket until after the SYN-ACK packet is sent; the only
5868 * viable choice is to regenerate the label like we do in
5869 * selinux_inet_conn_request(). See also selinux_ip_output()
5870 * for similar problems. */
5871 u32 skb_sid;
5872 struct sk_security_struct *sksec;
5873
5874 sksec = selinux_sock(sk);
5875 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5876 return NF_DROP;
5877 /* At this point, if the returned skb peerlbl is SECSID_NULL
5878 * and the packet has been through at least one XFRM
5879 * transformation then we must be dealing with the "final"
5880 * form of labeled IPsec packet; since we've already applied
5881 * all of our access controls on this packet we can safely
5882 * pass the packet. */
5883 if (skb_sid == SECSID_NULL) {
5884 switch (family) {
5885 case PF_INET:
5886 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5887 return NF_ACCEPT;
5888 break;
5889 case PF_INET6:
5890 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5891 return NF_ACCEPT;
5892 break;
5893 default:
5894 return NF_DROP_ERR(-ECONNREFUSED);
5895 }
5896 }
5897 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5898 return NF_DROP;
5899 secmark_perm = PACKET__SEND;
5900 } else {
5901 /* Locally generated packet, fetch the security label from the
5902 * associated socket. */
5903 struct sk_security_struct *sksec = selinux_sock(sk);
5904 peer_sid = sksec->sid;
5905 secmark_perm = PACKET__SEND;
5906 }
5907
5908 ifindex = state->out->ifindex;
5909 ad_net_init_from_iif(&ad, &net, ifindex, family);
5910 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5911 return NF_DROP;
5912
5913 if (secmark_active)
5914 if (avc_has_perm(peer_sid, skb->secmark,
5915 SECCLASS_PACKET, secmark_perm, &ad))
5916 return NF_DROP_ERR(-ECONNREFUSED);
5917
5918 if (peerlbl_active) {
5919 u32 if_sid;
5920 u32 node_sid;
5921
5922 if (sel_netif_sid(state->net, ifindex, &if_sid))
5923 return NF_DROP;
5924 if (avc_has_perm(peer_sid, if_sid,
5925 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5926 return NF_DROP_ERR(-ECONNREFUSED);
5927
5928 if (sel_netnode_sid(addrp, family, &node_sid))
5929 return NF_DROP;
5930 if (avc_has_perm(peer_sid, node_sid,
5931 SECCLASS_NODE, NODE__SENDTO, &ad))
5932 return NF_DROP_ERR(-ECONNREFUSED);
5933 }
5934
5935 return NF_ACCEPT;
5936 }
5937 #endif /* CONFIG_NETFILTER */
5938
nlmsg_sock_has_extended_perms(struct sock * sk,u32 perms,u16 nlmsg_type)5939 static int nlmsg_sock_has_extended_perms(struct sock *sk, u32 perms, u16 nlmsg_type)
5940 {
5941 struct sk_security_struct *sksec = sk->sk_security;
5942 struct common_audit_data ad;
5943 u8 driver;
5944 u8 xperm;
5945
5946 if (sock_skip_has_perm(sksec->sid))
5947 return 0;
5948
5949 ad.type = LSM_AUDIT_DATA_NLMSGTYPE;
5950 ad.u.nlmsg_type = nlmsg_type;
5951
5952 driver = nlmsg_type >> 8;
5953 xperm = nlmsg_type & 0xff;
5954
5955 return avc_has_extended_perms(current_sid(), sksec->sid, sksec->sclass,
5956 perms, driver, AVC_EXT_NLMSG, xperm, &ad);
5957 }
5958
selinux_netlink_send(struct sock * sk,struct sk_buff * skb)5959 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5960 {
5961 int rc = 0;
5962 unsigned int msg_len;
5963 unsigned int data_len = skb->len;
5964 unsigned char *data = skb->data;
5965 struct nlmsghdr *nlh;
5966 struct sk_security_struct *sksec = selinux_sock(sk);
5967 u16 sclass = sksec->sclass;
5968 u32 perm;
5969
5970 while (data_len >= nlmsg_total_size(0)) {
5971 nlh = (struct nlmsghdr *)data;
5972
5973 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
5974 * users which means we can't reject skb's with bogus
5975 * length fields; our solution is to follow what
5976 * netlink_rcv_skb() does and simply skip processing at
5977 * messages with length fields that are clearly junk
5978 */
5979 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5980 return 0;
5981
5982 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5983 if (rc == 0) {
5984 if (selinux_policycap_netlink_xperm()) {
5985 rc = nlmsg_sock_has_extended_perms(
5986 sk, perm, nlh->nlmsg_type);
5987 } else {
5988 rc = sock_has_perm(sk, perm);
5989 }
5990 if (rc)
5991 return rc;
5992 } else if (rc == -EINVAL) {
5993 /* -EINVAL is a missing msg/perm mapping */
5994 pr_warn_ratelimited("SELinux: unrecognized netlink"
5995 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5996 " pid=%d comm=%s\n",
5997 sk->sk_protocol, nlh->nlmsg_type,
5998 secclass_map[sclass - 1].name,
5999 task_pid_nr(current), current->comm);
6000 if (enforcing_enabled() &&
6001 !security_get_allow_unknown())
6002 return rc;
6003 rc = 0;
6004 } else if (rc == -ENOENT) {
6005 /* -ENOENT is a missing socket/class mapping, ignore */
6006 rc = 0;
6007 } else {
6008 return rc;
6009 }
6010
6011 /* move to the next message after applying netlink padding */
6012 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
6013 if (msg_len >= data_len)
6014 return 0;
6015 data_len -= msg_len;
6016 data += msg_len;
6017 }
6018
6019 return rc;
6020 }
6021
ipc_init_security(struct ipc_security_struct * isec,u16 sclass)6022 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
6023 {
6024 isec->sclass = sclass;
6025 isec->sid = current_sid();
6026 }
6027
ipc_has_perm(struct kern_ipc_perm * ipc_perms,u32 perms)6028 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
6029 u32 perms)
6030 {
6031 struct ipc_security_struct *isec;
6032 struct common_audit_data ad;
6033 u32 sid = current_sid();
6034
6035 isec = selinux_ipc(ipc_perms);
6036
6037 ad.type = LSM_AUDIT_DATA_IPC;
6038 ad.u.ipc_id = ipc_perms->key;
6039
6040 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
6041 }
6042
selinux_msg_msg_alloc_security(struct msg_msg * msg)6043 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6044 {
6045 struct msg_security_struct *msec;
6046
6047 msec = selinux_msg_msg(msg);
6048 msec->sid = SECINITSID_UNLABELED;
6049
6050 return 0;
6051 }
6052
6053 /* message queue security operations */
selinux_msg_queue_alloc_security(struct kern_ipc_perm * msq)6054 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6055 {
6056 struct ipc_security_struct *isec;
6057 struct common_audit_data ad;
6058 u32 sid = current_sid();
6059
6060 isec = selinux_ipc(msq);
6061 ipc_init_security(isec, SECCLASS_MSGQ);
6062
6063 ad.type = LSM_AUDIT_DATA_IPC;
6064 ad.u.ipc_id = msq->key;
6065
6066 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6067 MSGQ__CREATE, &ad);
6068 }
6069
selinux_msg_queue_associate(struct kern_ipc_perm * msq,int msqflg)6070 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6071 {
6072 struct ipc_security_struct *isec;
6073 struct common_audit_data ad;
6074 u32 sid = current_sid();
6075
6076 isec = selinux_ipc(msq);
6077
6078 ad.type = LSM_AUDIT_DATA_IPC;
6079 ad.u.ipc_id = msq->key;
6080
6081 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6082 MSGQ__ASSOCIATE, &ad);
6083 }
6084
selinux_msg_queue_msgctl(struct kern_ipc_perm * msq,int cmd)6085 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6086 {
6087 u32 perms;
6088
6089 switch (cmd) {
6090 case IPC_INFO:
6091 case MSG_INFO:
6092 /* No specific object, just general system-wide information. */
6093 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6094 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6095 case IPC_STAT:
6096 case MSG_STAT:
6097 case MSG_STAT_ANY:
6098 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6099 break;
6100 case IPC_SET:
6101 perms = MSGQ__SETATTR;
6102 break;
6103 case IPC_RMID:
6104 perms = MSGQ__DESTROY;
6105 break;
6106 default:
6107 return 0;
6108 }
6109
6110 return ipc_has_perm(msq, perms);
6111 }
6112
selinux_msg_queue_msgsnd(struct kern_ipc_perm * msq,struct msg_msg * msg,int msqflg)6113 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6114 {
6115 struct ipc_security_struct *isec;
6116 struct msg_security_struct *msec;
6117 struct common_audit_data ad;
6118 u32 sid = current_sid();
6119 int rc;
6120
6121 isec = selinux_ipc(msq);
6122 msec = selinux_msg_msg(msg);
6123
6124 /*
6125 * First time through, need to assign label to the message
6126 */
6127 if (msec->sid == SECINITSID_UNLABELED) {
6128 /*
6129 * Compute new sid based on current process and
6130 * message queue this message will be stored in
6131 */
6132 rc = security_transition_sid(sid, isec->sid,
6133 SECCLASS_MSG, NULL, &msec->sid);
6134 if (rc)
6135 return rc;
6136 }
6137
6138 ad.type = LSM_AUDIT_DATA_IPC;
6139 ad.u.ipc_id = msq->key;
6140
6141 /* Can this process write to the queue? */
6142 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6143 MSGQ__WRITE, &ad);
6144 if (!rc)
6145 /* Can this process send the message */
6146 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
6147 MSG__SEND, &ad);
6148 if (!rc)
6149 /* Can the message be put in the queue? */
6150 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
6151 MSGQ__ENQUEUE, &ad);
6152
6153 return rc;
6154 }
6155
selinux_msg_queue_msgrcv(struct kern_ipc_perm * msq,struct msg_msg * msg,struct task_struct * target,long type,int mode)6156 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6157 struct task_struct *target,
6158 long type, int mode)
6159 {
6160 struct ipc_security_struct *isec;
6161 struct msg_security_struct *msec;
6162 struct common_audit_data ad;
6163 u32 sid = task_sid_obj(target);
6164 int rc;
6165
6166 isec = selinux_ipc(msq);
6167 msec = selinux_msg_msg(msg);
6168
6169 ad.type = LSM_AUDIT_DATA_IPC;
6170 ad.u.ipc_id = msq->key;
6171
6172 rc = avc_has_perm(sid, isec->sid,
6173 SECCLASS_MSGQ, MSGQ__READ, &ad);
6174 if (!rc)
6175 rc = avc_has_perm(sid, msec->sid,
6176 SECCLASS_MSG, MSG__RECEIVE, &ad);
6177 return rc;
6178 }
6179
6180 /* Shared Memory security operations */
selinux_shm_alloc_security(struct kern_ipc_perm * shp)6181 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6182 {
6183 struct ipc_security_struct *isec;
6184 struct common_audit_data ad;
6185 u32 sid = current_sid();
6186
6187 isec = selinux_ipc(shp);
6188 ipc_init_security(isec, SECCLASS_SHM);
6189
6190 ad.type = LSM_AUDIT_DATA_IPC;
6191 ad.u.ipc_id = shp->key;
6192
6193 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6194 SHM__CREATE, &ad);
6195 }
6196
selinux_shm_associate(struct kern_ipc_perm * shp,int shmflg)6197 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6198 {
6199 struct ipc_security_struct *isec;
6200 struct common_audit_data ad;
6201 u32 sid = current_sid();
6202
6203 isec = selinux_ipc(shp);
6204
6205 ad.type = LSM_AUDIT_DATA_IPC;
6206 ad.u.ipc_id = shp->key;
6207
6208 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6209 SHM__ASSOCIATE, &ad);
6210 }
6211
6212 /* Note, at this point, shp is locked down */
selinux_shm_shmctl(struct kern_ipc_perm * shp,int cmd)6213 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6214 {
6215 u32 perms;
6216
6217 switch (cmd) {
6218 case IPC_INFO:
6219 case SHM_INFO:
6220 /* No specific object, just general system-wide information. */
6221 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6222 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6223 case IPC_STAT:
6224 case SHM_STAT:
6225 case SHM_STAT_ANY:
6226 perms = SHM__GETATTR | SHM__ASSOCIATE;
6227 break;
6228 case IPC_SET:
6229 perms = SHM__SETATTR;
6230 break;
6231 case SHM_LOCK:
6232 case SHM_UNLOCK:
6233 perms = SHM__LOCK;
6234 break;
6235 case IPC_RMID:
6236 perms = SHM__DESTROY;
6237 break;
6238 default:
6239 return 0;
6240 }
6241
6242 return ipc_has_perm(shp, perms);
6243 }
6244
selinux_shm_shmat(struct kern_ipc_perm * shp,char __user * shmaddr,int shmflg)6245 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6246 char __user *shmaddr, int shmflg)
6247 {
6248 u32 perms;
6249
6250 if (shmflg & SHM_RDONLY)
6251 perms = SHM__READ;
6252 else
6253 perms = SHM__READ | SHM__WRITE;
6254
6255 return ipc_has_perm(shp, perms);
6256 }
6257
6258 /* Semaphore security operations */
selinux_sem_alloc_security(struct kern_ipc_perm * sma)6259 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6260 {
6261 struct ipc_security_struct *isec;
6262 struct common_audit_data ad;
6263 u32 sid = current_sid();
6264
6265 isec = selinux_ipc(sma);
6266 ipc_init_security(isec, SECCLASS_SEM);
6267
6268 ad.type = LSM_AUDIT_DATA_IPC;
6269 ad.u.ipc_id = sma->key;
6270
6271 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6272 SEM__CREATE, &ad);
6273 }
6274
selinux_sem_associate(struct kern_ipc_perm * sma,int semflg)6275 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6276 {
6277 struct ipc_security_struct *isec;
6278 struct common_audit_data ad;
6279 u32 sid = current_sid();
6280
6281 isec = selinux_ipc(sma);
6282
6283 ad.type = LSM_AUDIT_DATA_IPC;
6284 ad.u.ipc_id = sma->key;
6285
6286 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6287 SEM__ASSOCIATE, &ad);
6288 }
6289
6290 /* Note, at this point, sma is locked down */
selinux_sem_semctl(struct kern_ipc_perm * sma,int cmd)6291 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6292 {
6293 int err;
6294 u32 perms;
6295
6296 switch (cmd) {
6297 case IPC_INFO:
6298 case SEM_INFO:
6299 /* No specific object, just general system-wide information. */
6300 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6301 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6302 case GETPID:
6303 case GETNCNT:
6304 case GETZCNT:
6305 perms = SEM__GETATTR;
6306 break;
6307 case GETVAL:
6308 case GETALL:
6309 perms = SEM__READ;
6310 break;
6311 case SETVAL:
6312 case SETALL:
6313 perms = SEM__WRITE;
6314 break;
6315 case IPC_RMID:
6316 perms = SEM__DESTROY;
6317 break;
6318 case IPC_SET:
6319 perms = SEM__SETATTR;
6320 break;
6321 case IPC_STAT:
6322 case SEM_STAT:
6323 case SEM_STAT_ANY:
6324 perms = SEM__GETATTR | SEM__ASSOCIATE;
6325 break;
6326 default:
6327 return 0;
6328 }
6329
6330 err = ipc_has_perm(sma, perms);
6331 return err;
6332 }
6333
selinux_sem_semop(struct kern_ipc_perm * sma,struct sembuf * sops,unsigned nsops,int alter)6334 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6335 struct sembuf *sops, unsigned nsops, int alter)
6336 {
6337 u32 perms;
6338
6339 if (alter)
6340 perms = SEM__READ | SEM__WRITE;
6341 else
6342 perms = SEM__READ;
6343
6344 return ipc_has_perm(sma, perms);
6345 }
6346
selinux_ipc_permission(struct kern_ipc_perm * ipcp,short flag)6347 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6348 {
6349 u32 av = 0;
6350
6351 av = 0;
6352 if (flag & S_IRUGO)
6353 av |= IPC__UNIX_READ;
6354 if (flag & S_IWUGO)
6355 av |= IPC__UNIX_WRITE;
6356
6357 if (av == 0)
6358 return 0;
6359
6360 return ipc_has_perm(ipcp, av);
6361 }
6362
selinux_ipc_getlsmprop(struct kern_ipc_perm * ipcp,struct lsm_prop * prop)6363 static void selinux_ipc_getlsmprop(struct kern_ipc_perm *ipcp,
6364 struct lsm_prop *prop)
6365 {
6366 struct ipc_security_struct *isec = selinux_ipc(ipcp);
6367 prop->selinux.secid = isec->sid;
6368 }
6369
selinux_d_instantiate(struct dentry * dentry,struct inode * inode)6370 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6371 {
6372 if (inode)
6373 inode_doinit_with_dentry(inode, dentry);
6374 }
6375
selinux_lsm_getattr(unsigned int attr,struct task_struct * p,char ** value)6376 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
6377 char **value)
6378 {
6379 const struct task_security_struct *tsec;
6380 int error;
6381 u32 sid;
6382 u32 len;
6383
6384 rcu_read_lock();
6385 tsec = selinux_cred(__task_cred(p));
6386 if (p != current) {
6387 error = avc_has_perm(current_sid(), tsec->sid,
6388 SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6389 if (error)
6390 goto err_unlock;
6391 }
6392 switch (attr) {
6393 case LSM_ATTR_CURRENT:
6394 sid = tsec->sid;
6395 break;
6396 case LSM_ATTR_PREV:
6397 sid = tsec->osid;
6398 break;
6399 case LSM_ATTR_EXEC:
6400 sid = tsec->exec_sid;
6401 break;
6402 case LSM_ATTR_FSCREATE:
6403 sid = tsec->create_sid;
6404 break;
6405 case LSM_ATTR_KEYCREATE:
6406 sid = tsec->keycreate_sid;
6407 break;
6408 case LSM_ATTR_SOCKCREATE:
6409 sid = tsec->sockcreate_sid;
6410 break;
6411 default:
6412 error = -EOPNOTSUPP;
6413 goto err_unlock;
6414 }
6415 rcu_read_unlock();
6416
6417 if (sid == SECSID_NULL) {
6418 *value = NULL;
6419 return 0;
6420 }
6421
6422 error = security_sid_to_context(sid, value, &len);
6423 if (error)
6424 return error;
6425 return len;
6426
6427 err_unlock:
6428 rcu_read_unlock();
6429 return error;
6430 }
6431
selinux_lsm_setattr(u64 attr,void * value,size_t size)6432 static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
6433 {
6434 struct task_security_struct *tsec;
6435 struct cred *new;
6436 u32 mysid = current_sid(), sid = 0, ptsid;
6437 int error;
6438 char *str = value;
6439
6440 /*
6441 * Basic control over ability to set these attributes at all.
6442 */
6443 switch (attr) {
6444 case LSM_ATTR_EXEC:
6445 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6446 PROCESS__SETEXEC, NULL);
6447 break;
6448 case LSM_ATTR_FSCREATE:
6449 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6450 PROCESS__SETFSCREATE, NULL);
6451 break;
6452 case LSM_ATTR_KEYCREATE:
6453 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6454 PROCESS__SETKEYCREATE, NULL);
6455 break;
6456 case LSM_ATTR_SOCKCREATE:
6457 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6458 PROCESS__SETSOCKCREATE, NULL);
6459 break;
6460 case LSM_ATTR_CURRENT:
6461 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6462 PROCESS__SETCURRENT, NULL);
6463 break;
6464 default:
6465 error = -EOPNOTSUPP;
6466 break;
6467 }
6468 if (error)
6469 return error;
6470
6471 /* Obtain a SID for the context, if one was specified. */
6472 if (size && str[0] && str[0] != '\n') {
6473 if (str[size-1] == '\n') {
6474 str[size-1] = 0;
6475 size--;
6476 }
6477 error = security_context_to_sid(value, size,
6478 &sid, GFP_KERNEL);
6479 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
6480 if (!has_cap_mac_admin(true)) {
6481 struct audit_buffer *ab;
6482 size_t audit_size;
6483
6484 /* We strip a nul only if it is at the end,
6485 * otherwise the context contains a nul and
6486 * we should audit that */
6487 if (str[size - 1] == '\0')
6488 audit_size = size - 1;
6489 else
6490 audit_size = size;
6491 ab = audit_log_start(audit_context(),
6492 GFP_ATOMIC,
6493 AUDIT_SELINUX_ERR);
6494 if (!ab)
6495 return error;
6496 audit_log_format(ab, "op=fscreate invalid_context=");
6497 audit_log_n_untrustedstring(ab, value,
6498 audit_size);
6499 audit_log_end(ab);
6500
6501 return error;
6502 }
6503 error = security_context_to_sid_force(value, size,
6504 &sid);
6505 }
6506 if (error)
6507 return error;
6508 }
6509
6510 new = prepare_creds();
6511 if (!new)
6512 return -ENOMEM;
6513
6514 /* Permission checking based on the specified context is
6515 performed during the actual operation (execve,
6516 open/mkdir/...), when we know the full context of the
6517 operation. See selinux_bprm_creds_for_exec for the execve
6518 checks and may_create for the file creation checks. The
6519 operation will then fail if the context is not permitted. */
6520 tsec = selinux_cred(new);
6521 if (attr == LSM_ATTR_EXEC) {
6522 tsec->exec_sid = sid;
6523 } else if (attr == LSM_ATTR_FSCREATE) {
6524 tsec->create_sid = sid;
6525 } else if (attr == LSM_ATTR_KEYCREATE) {
6526 if (sid) {
6527 error = avc_has_perm(mysid, sid,
6528 SECCLASS_KEY, KEY__CREATE, NULL);
6529 if (error)
6530 goto abort_change;
6531 }
6532 tsec->keycreate_sid = sid;
6533 } else if (attr == LSM_ATTR_SOCKCREATE) {
6534 tsec->sockcreate_sid = sid;
6535 } else if (attr == LSM_ATTR_CURRENT) {
6536 error = -EINVAL;
6537 if (sid == 0)
6538 goto abort_change;
6539
6540 if (!current_is_single_threaded()) {
6541 error = security_bounded_transition(tsec->sid, sid);
6542 if (error)
6543 goto abort_change;
6544 }
6545
6546 /* Check permissions for the transition. */
6547 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6548 PROCESS__DYNTRANSITION, NULL);
6549 if (error)
6550 goto abort_change;
6551
6552 /* Check for ptracing, and update the task SID if ok.
6553 Otherwise, leave SID unchanged and fail. */
6554 ptsid = ptrace_parent_sid();
6555 if (ptsid != 0) {
6556 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
6557 PROCESS__PTRACE, NULL);
6558 if (error)
6559 goto abort_change;
6560 }
6561
6562 tsec->sid = sid;
6563 } else {
6564 error = -EINVAL;
6565 goto abort_change;
6566 }
6567
6568 commit_creds(new);
6569 return size;
6570
6571 abort_change:
6572 abort_creds(new);
6573 return error;
6574 }
6575
6576 /**
6577 * selinux_getselfattr - Get SELinux current task attributes
6578 * @attr: the requested attribute
6579 * @ctx: buffer to receive the result
6580 * @size: buffer size (input), buffer size used (output)
6581 * @flags: unused
6582 *
6583 * Fill the passed user space @ctx with the details of the requested
6584 * attribute.
6585 *
6586 * Returns the number of attributes on success, an error code otherwise.
6587 * There will only ever be one attribute.
6588 */
selinux_getselfattr(unsigned int attr,struct lsm_ctx __user * ctx,u32 * size,u32 flags)6589 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
6590 u32 *size, u32 flags)
6591 {
6592 int rc;
6593 char *val = NULL;
6594 int val_len;
6595
6596 val_len = selinux_lsm_getattr(attr, current, &val);
6597 if (val_len < 0)
6598 return val_len;
6599 rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0);
6600 kfree(val);
6601 return (!rc ? 1 : rc);
6602 }
6603
selinux_setselfattr(unsigned int attr,struct lsm_ctx * ctx,u32 size,u32 flags)6604 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
6605 u32 size, u32 flags)
6606 {
6607 int rc;
6608
6609 rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len);
6610 if (rc > 0)
6611 return 0;
6612 return rc;
6613 }
6614
selinux_getprocattr(struct task_struct * p,const char * name,char ** value)6615 static int selinux_getprocattr(struct task_struct *p,
6616 const char *name, char **value)
6617 {
6618 unsigned int attr = lsm_name_to_attr(name);
6619 int rc;
6620
6621 if (attr) {
6622 rc = selinux_lsm_getattr(attr, p, value);
6623 if (rc != -EOPNOTSUPP)
6624 return rc;
6625 }
6626
6627 return -EINVAL;
6628 }
6629
selinux_setprocattr(const char * name,void * value,size_t size)6630 static int selinux_setprocattr(const char *name, void *value, size_t size)
6631 {
6632 int attr = lsm_name_to_attr(name);
6633
6634 if (attr)
6635 return selinux_lsm_setattr(attr, value, size);
6636 return -EINVAL;
6637 }
6638
selinux_ismaclabel(const char * name)6639 static int selinux_ismaclabel(const char *name)
6640 {
6641 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6642 }
6643
selinux_secid_to_secctx(u32 secid,struct lsm_context * cp)6644 static int selinux_secid_to_secctx(u32 secid, struct lsm_context *cp)
6645 {
6646 u32 seclen;
6647 int ret;
6648
6649 if (cp) {
6650 cp->id = LSM_ID_SELINUX;
6651 ret = security_sid_to_context(secid, &cp->context, &cp->len);
6652 if (ret < 0)
6653 return ret;
6654 return cp->len;
6655 }
6656 ret = security_sid_to_context(secid, NULL, &seclen);
6657 if (ret < 0)
6658 return ret;
6659 return seclen;
6660 }
6661
selinux_lsmprop_to_secctx(struct lsm_prop * prop,struct lsm_context * cp)6662 static int selinux_lsmprop_to_secctx(struct lsm_prop *prop,
6663 struct lsm_context *cp)
6664 {
6665 return selinux_secid_to_secctx(prop->selinux.secid, cp);
6666 }
6667
selinux_secctx_to_secid(const char * secdata,u32 seclen,u32 * secid)6668 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6669 {
6670 return security_context_to_sid(secdata, seclen,
6671 secid, GFP_KERNEL);
6672 }
6673
selinux_release_secctx(struct lsm_context * cp)6674 static void selinux_release_secctx(struct lsm_context *cp)
6675 {
6676 if (cp->id == LSM_ID_SELINUX) {
6677 kfree(cp->context);
6678 cp->context = NULL;
6679 cp->id = LSM_ID_UNDEF;
6680 }
6681 }
6682
selinux_inode_invalidate_secctx(struct inode * inode)6683 static void selinux_inode_invalidate_secctx(struct inode *inode)
6684 {
6685 struct inode_security_struct *isec = selinux_inode(inode);
6686
6687 spin_lock(&isec->lock);
6688 isec->initialized = LABEL_INVALID;
6689 spin_unlock(&isec->lock);
6690 }
6691
6692 /*
6693 * called with inode->i_mutex locked
6694 */
selinux_inode_notifysecctx(struct inode * inode,void * ctx,u32 ctxlen)6695 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6696 {
6697 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6698 ctx, ctxlen, 0);
6699 /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6700 return rc == -EOPNOTSUPP ? 0 : rc;
6701 }
6702
6703 /*
6704 * called with inode->i_mutex locked
6705 */
selinux_inode_setsecctx(struct dentry * dentry,void * ctx,u32 ctxlen)6706 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6707 {
6708 return __vfs_setxattr_locked(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6709 ctx, ctxlen, 0, NULL);
6710 }
6711
selinux_inode_getsecctx(struct inode * inode,struct lsm_context * cp)6712 static int selinux_inode_getsecctx(struct inode *inode, struct lsm_context *cp)
6713 {
6714 int len;
6715 len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6716 XATTR_SELINUX_SUFFIX,
6717 (void **)&cp->context, true);
6718 if (len < 0)
6719 return len;
6720 cp->len = len;
6721 cp->id = LSM_ID_SELINUX;
6722 return 0;
6723 }
6724 #ifdef CONFIG_KEYS
6725
selinux_key_alloc(struct key * k,const struct cred * cred,unsigned long flags)6726 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6727 unsigned long flags)
6728 {
6729 const struct task_security_struct *tsec;
6730 struct key_security_struct *ksec = selinux_key(k);
6731
6732 tsec = selinux_cred(cred);
6733 if (tsec->keycreate_sid)
6734 ksec->sid = tsec->keycreate_sid;
6735 else
6736 ksec->sid = tsec->sid;
6737
6738 return 0;
6739 }
6740
selinux_key_permission(key_ref_t key_ref,const struct cred * cred,enum key_need_perm need_perm)6741 static int selinux_key_permission(key_ref_t key_ref,
6742 const struct cred *cred,
6743 enum key_need_perm need_perm)
6744 {
6745 struct key *key;
6746 struct key_security_struct *ksec;
6747 u32 perm, sid;
6748
6749 switch (need_perm) {
6750 case KEY_NEED_VIEW:
6751 perm = KEY__VIEW;
6752 break;
6753 case KEY_NEED_READ:
6754 perm = KEY__READ;
6755 break;
6756 case KEY_NEED_WRITE:
6757 perm = KEY__WRITE;
6758 break;
6759 case KEY_NEED_SEARCH:
6760 perm = KEY__SEARCH;
6761 break;
6762 case KEY_NEED_LINK:
6763 perm = KEY__LINK;
6764 break;
6765 case KEY_NEED_SETATTR:
6766 perm = KEY__SETATTR;
6767 break;
6768 case KEY_NEED_UNLINK:
6769 case KEY_SYSADMIN_OVERRIDE:
6770 case KEY_AUTHTOKEN_OVERRIDE:
6771 case KEY_DEFER_PERM_CHECK:
6772 return 0;
6773 default:
6774 WARN_ON(1);
6775 return -EPERM;
6776
6777 }
6778
6779 sid = cred_sid(cred);
6780 key = key_ref_to_ptr(key_ref);
6781 ksec = selinux_key(key);
6782
6783 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6784 }
6785
selinux_key_getsecurity(struct key * key,char ** _buffer)6786 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6787 {
6788 struct key_security_struct *ksec = selinux_key(key);
6789 char *context = NULL;
6790 unsigned len;
6791 int rc;
6792
6793 rc = security_sid_to_context(ksec->sid,
6794 &context, &len);
6795 if (!rc)
6796 rc = len;
6797 *_buffer = context;
6798 return rc;
6799 }
6800
6801 #ifdef CONFIG_KEY_NOTIFICATIONS
selinux_watch_key(struct key * key)6802 static int selinux_watch_key(struct key *key)
6803 {
6804 struct key_security_struct *ksec = selinux_key(key);
6805 u32 sid = current_sid();
6806
6807 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6808 }
6809 #endif
6810 #endif
6811
6812 #ifdef CONFIG_SECURITY_INFINIBAND
selinux_ib_pkey_access(void * ib_sec,u64 subnet_prefix,u16 pkey_val)6813 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6814 {
6815 struct common_audit_data ad;
6816 int err;
6817 u32 sid = 0;
6818 struct ib_security_struct *sec = ib_sec;
6819 struct lsm_ibpkey_audit ibpkey;
6820
6821 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6822 if (err)
6823 return err;
6824
6825 ad.type = LSM_AUDIT_DATA_IBPKEY;
6826 ibpkey.subnet_prefix = subnet_prefix;
6827 ibpkey.pkey = pkey_val;
6828 ad.u.ibpkey = &ibpkey;
6829 return avc_has_perm(sec->sid, sid,
6830 SECCLASS_INFINIBAND_PKEY,
6831 INFINIBAND_PKEY__ACCESS, &ad);
6832 }
6833
selinux_ib_endport_manage_subnet(void * ib_sec,const char * dev_name,u8 port_num)6834 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6835 u8 port_num)
6836 {
6837 struct common_audit_data ad;
6838 int err;
6839 u32 sid = 0;
6840 struct ib_security_struct *sec = ib_sec;
6841 struct lsm_ibendport_audit ibendport;
6842
6843 err = security_ib_endport_sid(dev_name, port_num,
6844 &sid);
6845
6846 if (err)
6847 return err;
6848
6849 ad.type = LSM_AUDIT_DATA_IBENDPORT;
6850 ibendport.dev_name = dev_name;
6851 ibendport.port = port_num;
6852 ad.u.ibendport = &ibendport;
6853 return avc_has_perm(sec->sid, sid,
6854 SECCLASS_INFINIBAND_ENDPORT,
6855 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6856 }
6857
selinux_ib_alloc_security(void * ib_sec)6858 static int selinux_ib_alloc_security(void *ib_sec)
6859 {
6860 struct ib_security_struct *sec = selinux_ib(ib_sec);
6861
6862 sec->sid = current_sid();
6863 return 0;
6864 }
6865 #endif
6866
6867 #ifdef CONFIG_BPF_SYSCALL
selinux_bpf(int cmd,union bpf_attr * attr,unsigned int size)6868 static int selinux_bpf(int cmd, union bpf_attr *attr,
6869 unsigned int size)
6870 {
6871 u32 sid = current_sid();
6872 int ret;
6873
6874 switch (cmd) {
6875 case BPF_MAP_CREATE:
6876 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6877 NULL);
6878 break;
6879 case BPF_PROG_LOAD:
6880 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6881 NULL);
6882 break;
6883 default:
6884 ret = 0;
6885 break;
6886 }
6887
6888 return ret;
6889 }
6890
bpf_map_fmode_to_av(fmode_t fmode)6891 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6892 {
6893 u32 av = 0;
6894
6895 if (fmode & FMODE_READ)
6896 av |= BPF__MAP_READ;
6897 if (fmode & FMODE_WRITE)
6898 av |= BPF__MAP_WRITE;
6899 return av;
6900 }
6901
6902 /* This function will check the file pass through unix socket or binder to see
6903 * if it is a bpf related object. And apply corresponding checks on the bpf
6904 * object based on the type. The bpf maps and programs, not like other files and
6905 * socket, are using a shared anonymous inode inside the kernel as their inode.
6906 * So checking that inode cannot identify if the process have privilege to
6907 * access the bpf object and that's why we have to add this additional check in
6908 * selinux_file_receive and selinux_binder_transfer_files.
6909 */
bpf_fd_pass(const struct file * file,u32 sid)6910 static int bpf_fd_pass(const struct file *file, u32 sid)
6911 {
6912 struct bpf_security_struct *bpfsec;
6913 struct bpf_prog *prog;
6914 struct bpf_map *map;
6915 int ret;
6916
6917 if (file->f_op == &bpf_map_fops) {
6918 map = file->private_data;
6919 bpfsec = map->security;
6920 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6921 bpf_map_fmode_to_av(file->f_mode), NULL);
6922 if (ret)
6923 return ret;
6924 } else if (file->f_op == &bpf_prog_fops) {
6925 prog = file->private_data;
6926 bpfsec = prog->aux->security;
6927 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6928 BPF__PROG_RUN, NULL);
6929 if (ret)
6930 return ret;
6931 }
6932 return 0;
6933 }
6934
selinux_bpf_map(struct bpf_map * map,fmode_t fmode)6935 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6936 {
6937 u32 sid = current_sid();
6938 struct bpf_security_struct *bpfsec;
6939
6940 bpfsec = map->security;
6941 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6942 bpf_map_fmode_to_av(fmode), NULL);
6943 }
6944
selinux_bpf_prog(struct bpf_prog * prog)6945 static int selinux_bpf_prog(struct bpf_prog *prog)
6946 {
6947 u32 sid = current_sid();
6948 struct bpf_security_struct *bpfsec;
6949
6950 bpfsec = prog->aux->security;
6951 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6952 BPF__PROG_RUN, NULL);
6953 }
6954
selinux_bpf_map_create(struct bpf_map * map,union bpf_attr * attr,struct bpf_token * token)6955 static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
6956 struct bpf_token *token)
6957 {
6958 struct bpf_security_struct *bpfsec;
6959
6960 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6961 if (!bpfsec)
6962 return -ENOMEM;
6963
6964 bpfsec->sid = current_sid();
6965 map->security = bpfsec;
6966
6967 return 0;
6968 }
6969
selinux_bpf_map_free(struct bpf_map * map)6970 static void selinux_bpf_map_free(struct bpf_map *map)
6971 {
6972 struct bpf_security_struct *bpfsec = map->security;
6973
6974 map->security = NULL;
6975 kfree(bpfsec);
6976 }
6977
selinux_bpf_prog_load(struct bpf_prog * prog,union bpf_attr * attr,struct bpf_token * token)6978 static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
6979 struct bpf_token *token)
6980 {
6981 struct bpf_security_struct *bpfsec;
6982
6983 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6984 if (!bpfsec)
6985 return -ENOMEM;
6986
6987 bpfsec->sid = current_sid();
6988 prog->aux->security = bpfsec;
6989
6990 return 0;
6991 }
6992
selinux_bpf_prog_free(struct bpf_prog * prog)6993 static void selinux_bpf_prog_free(struct bpf_prog *prog)
6994 {
6995 struct bpf_security_struct *bpfsec = prog->aux->security;
6996
6997 prog->aux->security = NULL;
6998 kfree(bpfsec);
6999 }
7000
selinux_bpf_token_create(struct bpf_token * token,union bpf_attr * attr,const struct path * path)7001 static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
7002 const struct path *path)
7003 {
7004 struct bpf_security_struct *bpfsec;
7005
7006 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
7007 if (!bpfsec)
7008 return -ENOMEM;
7009
7010 bpfsec->sid = current_sid();
7011 token->security = bpfsec;
7012
7013 return 0;
7014 }
7015
selinux_bpf_token_free(struct bpf_token * token)7016 static void selinux_bpf_token_free(struct bpf_token *token)
7017 {
7018 struct bpf_security_struct *bpfsec = token->security;
7019
7020 token->security = NULL;
7021 kfree(bpfsec);
7022 }
7023 #endif
7024
7025 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
7026 .lbs_cred = sizeof(struct task_security_struct),
7027 .lbs_file = sizeof(struct file_security_struct),
7028 .lbs_inode = sizeof(struct inode_security_struct),
7029 .lbs_ipc = sizeof(struct ipc_security_struct),
7030 .lbs_key = sizeof(struct key_security_struct),
7031 .lbs_msg_msg = sizeof(struct msg_security_struct),
7032 #ifdef CONFIG_PERF_EVENTS
7033 .lbs_perf_event = sizeof(struct perf_event_security_struct),
7034 #endif
7035 .lbs_sock = sizeof(struct sk_security_struct),
7036 .lbs_superblock = sizeof(struct superblock_security_struct),
7037 .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS,
7038 .lbs_tun_dev = sizeof(struct tun_security_struct),
7039 .lbs_ib = sizeof(struct ib_security_struct),
7040 };
7041
7042 #ifdef CONFIG_PERF_EVENTS
selinux_perf_event_open(struct perf_event_attr * attr,int type)7043 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
7044 {
7045 u32 requested, sid = current_sid();
7046
7047 if (type == PERF_SECURITY_OPEN)
7048 requested = PERF_EVENT__OPEN;
7049 else if (type == PERF_SECURITY_CPU)
7050 requested = PERF_EVENT__CPU;
7051 else if (type == PERF_SECURITY_KERNEL)
7052 requested = PERF_EVENT__KERNEL;
7053 else if (type == PERF_SECURITY_TRACEPOINT)
7054 requested = PERF_EVENT__TRACEPOINT;
7055 else
7056 return -EINVAL;
7057
7058 return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
7059 requested, NULL);
7060 }
7061
selinux_perf_event_alloc(struct perf_event * event)7062 static int selinux_perf_event_alloc(struct perf_event *event)
7063 {
7064 struct perf_event_security_struct *perfsec;
7065
7066 perfsec = selinux_perf_event(event->security);
7067 perfsec->sid = current_sid();
7068
7069 return 0;
7070 }
7071
selinux_perf_event_read(struct perf_event * event)7072 static int selinux_perf_event_read(struct perf_event *event)
7073 {
7074 struct perf_event_security_struct *perfsec = event->security;
7075 u32 sid = current_sid();
7076
7077 return avc_has_perm(sid, perfsec->sid,
7078 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7079 }
7080
selinux_perf_event_write(struct perf_event * event)7081 static int selinux_perf_event_write(struct perf_event *event)
7082 {
7083 struct perf_event_security_struct *perfsec = event->security;
7084 u32 sid = current_sid();
7085
7086 return avc_has_perm(sid, perfsec->sid,
7087 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7088 }
7089 #endif
7090
7091 #ifdef CONFIG_IO_URING
7092 /**
7093 * selinux_uring_override_creds - check the requested cred override
7094 * @new: the target creds
7095 *
7096 * Check to see if the current task is allowed to override it's credentials
7097 * to service an io_uring operation.
7098 */
selinux_uring_override_creds(const struct cred * new)7099 static int selinux_uring_override_creds(const struct cred *new)
7100 {
7101 return avc_has_perm(current_sid(), cred_sid(new),
7102 SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
7103 }
7104
7105 /**
7106 * selinux_uring_sqpoll - check if a io_uring polling thread can be created
7107 *
7108 * Check to see if the current task is allowed to create a new io_uring
7109 * kernel polling thread.
7110 */
selinux_uring_sqpoll(void)7111 static int selinux_uring_sqpoll(void)
7112 {
7113 u32 sid = current_sid();
7114
7115 return avc_has_perm(sid, sid,
7116 SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
7117 }
7118
7119 /**
7120 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
7121 * @ioucmd: the io_uring command structure
7122 *
7123 * Check to see if the current domain is allowed to execute an
7124 * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
7125 *
7126 */
selinux_uring_cmd(struct io_uring_cmd * ioucmd)7127 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
7128 {
7129 struct file *file = ioucmd->file;
7130 struct inode *inode = file_inode(file);
7131 struct inode_security_struct *isec = selinux_inode(inode);
7132 struct common_audit_data ad;
7133
7134 ad.type = LSM_AUDIT_DATA_FILE;
7135 ad.u.file = file;
7136
7137 return avc_has_perm(current_sid(), isec->sid,
7138 SECCLASS_IO_URING, IO_URING__CMD, &ad);
7139 }
7140 #endif /* CONFIG_IO_URING */
7141
7142 static const struct lsm_id selinux_lsmid = {
7143 .name = "selinux",
7144 .id = LSM_ID_SELINUX,
7145 };
7146
7147 /*
7148 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7149 * 1. any hooks that don't belong to (2.) or (3.) below,
7150 * 2. hooks that both access structures allocated by other hooks, and allocate
7151 * structures that can be later accessed by other hooks (mostly "cloning"
7152 * hooks),
7153 * 3. hooks that only allocate structures that can be later accessed by other
7154 * hooks ("allocating" hooks).
7155 *
7156 * Please follow block comment delimiters in the list to keep this order.
7157 */
7158 static struct security_hook_list selinux_hooks[] __ro_after_init = {
7159 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7160 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7161 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7162 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7163
7164 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7165 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7166 LSM_HOOK_INIT(capget, selinux_capget),
7167 LSM_HOOK_INIT(capset, selinux_capset),
7168 LSM_HOOK_INIT(capable, selinux_capable),
7169 LSM_HOOK_INIT(quotactl, selinux_quotactl),
7170 LSM_HOOK_INIT(quota_on, selinux_quota_on),
7171 LSM_HOOK_INIT(syslog, selinux_syslog),
7172 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7173
7174 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7175
7176 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7177 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7178 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7179
7180 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7181 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7182 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7183 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7184 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7185 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7186 LSM_HOOK_INIT(sb_mount, selinux_mount),
7187 LSM_HOOK_INIT(sb_umount, selinux_umount),
7188 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7189 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7190
7191 LSM_HOOK_INIT(move_mount, selinux_move_mount),
7192
7193 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7194 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7195
7196 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7197 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7198 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7199 LSM_HOOK_INIT(inode_create, selinux_inode_create),
7200 LSM_HOOK_INIT(inode_link, selinux_inode_link),
7201 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7202 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7203 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7204 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7205 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7206 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7207 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7208 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7209 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7210 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7211 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7212 LSM_HOOK_INIT(inode_xattr_skipcap, selinux_inode_xattr_skipcap),
7213 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7214 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7215 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7216 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7217 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7218 LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7219 LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7220 LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7221 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7222 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7223 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7224 LSM_HOOK_INIT(inode_getlsmprop, selinux_inode_getlsmprop),
7225 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7226 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7227 LSM_HOOK_INIT(path_notify, selinux_path_notify),
7228
7229 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7230
7231 LSM_HOOK_INIT(file_permission, selinux_file_permission),
7232 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7233 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7234 LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat),
7235 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7236 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7237 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7238 LSM_HOOK_INIT(file_lock, selinux_file_lock),
7239 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7240 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7241 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7242 LSM_HOOK_INIT(file_receive, selinux_file_receive),
7243
7244 LSM_HOOK_INIT(file_open, selinux_file_open),
7245
7246 LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7247 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7248 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7249 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7250 LSM_HOOK_INIT(cred_getlsmprop, selinux_cred_getlsmprop),
7251 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7252 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7253 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7254 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7255 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7256 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7257 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7258 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7259 LSM_HOOK_INIT(current_getlsmprop_subj, selinux_current_getlsmprop_subj),
7260 LSM_HOOK_INIT(task_getlsmprop_obj, selinux_task_getlsmprop_obj),
7261 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7262 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7263 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7264 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7265 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7266 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7267 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7268 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7269 LSM_HOOK_INIT(task_kill, selinux_task_kill),
7270 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7271 LSM_HOOK_INIT(userns_create, selinux_userns_create),
7272
7273 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7274 LSM_HOOK_INIT(ipc_getlsmprop, selinux_ipc_getlsmprop),
7275
7276 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7277 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7278 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7279 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7280
7281 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7282 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7283 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7284
7285 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7286 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7287 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7288
7289 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7290
7291 LSM_HOOK_INIT(getselfattr, selinux_getselfattr),
7292 LSM_HOOK_INIT(setselfattr, selinux_setselfattr),
7293 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7294 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7295
7296 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7297 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7298 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7299 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7300 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7301 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7302
7303 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7304 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7305
7306 LSM_HOOK_INIT(socket_create, selinux_socket_create),
7307 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7308 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7309 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7310 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7311 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7312 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7313 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7314 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7315 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7316 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7317 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7318 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7319 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7320 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7321 LSM_HOOK_INIT(socket_getpeersec_stream,
7322 selinux_socket_getpeersec_stream),
7323 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7324 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7325 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7326 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7327 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7328 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7329 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7330 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7331 LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7332 LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow),
7333 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7334 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7335 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7336 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7337 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7338 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7339 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7340 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7341 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7342 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7343 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7344 #ifdef CONFIG_SECURITY_INFINIBAND
7345 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7346 LSM_HOOK_INIT(ib_endport_manage_subnet,
7347 selinux_ib_endport_manage_subnet),
7348 #endif
7349 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7350 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7351 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7352 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7353 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7354 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7355 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7356 selinux_xfrm_state_pol_flow_match),
7357 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7358 #endif
7359
7360 #ifdef CONFIG_KEYS
7361 LSM_HOOK_INIT(key_permission, selinux_key_permission),
7362 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7363 #ifdef CONFIG_KEY_NOTIFICATIONS
7364 LSM_HOOK_INIT(watch_key, selinux_watch_key),
7365 #endif
7366 #endif
7367
7368 #ifdef CONFIG_AUDIT
7369 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7370 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7371 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7372 #endif
7373
7374 #ifdef CONFIG_BPF_SYSCALL
7375 LSM_HOOK_INIT(bpf, selinux_bpf),
7376 LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7377 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7378 LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free),
7379 LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free),
7380 LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free),
7381 #endif
7382
7383 #ifdef CONFIG_PERF_EVENTS
7384 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7385 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7386 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7387 #endif
7388
7389 #ifdef CONFIG_IO_URING
7390 LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7391 LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7392 LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7393 #endif
7394
7395 /*
7396 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7397 */
7398 LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount),
7399 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7400 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7401 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7402 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7403 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7404 #endif
7405
7406 /*
7407 * PUT "ALLOCATING" HOOKS HERE
7408 */
7409 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7410 LSM_HOOK_INIT(msg_queue_alloc_security,
7411 selinux_msg_queue_alloc_security),
7412 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7413 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7414 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7415 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7416 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7417 LSM_HOOK_INIT(lsmprop_to_secctx, selinux_lsmprop_to_secctx),
7418 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7419 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7420 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7421 #ifdef CONFIG_SECURITY_INFINIBAND
7422 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7423 #endif
7424 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7425 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7426 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7427 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7428 selinux_xfrm_state_alloc_acquire),
7429 #endif
7430 #ifdef CONFIG_KEYS
7431 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7432 #endif
7433 #ifdef CONFIG_AUDIT
7434 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7435 #endif
7436 #ifdef CONFIG_BPF_SYSCALL
7437 LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create),
7438 LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load),
7439 LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create),
7440 #endif
7441 #ifdef CONFIG_PERF_EVENTS
7442 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7443 #endif
7444 };
7445
selinux_init(void)7446 static __init int selinux_init(void)
7447 {
7448 pr_info("SELinux: Initializing.\n");
7449
7450 memset(&selinux_state, 0, sizeof(selinux_state));
7451 enforcing_set(selinux_enforcing_boot);
7452 selinux_avc_init();
7453 mutex_init(&selinux_state.status_lock);
7454 mutex_init(&selinux_state.policy_mutex);
7455
7456 /* Set the security state for the initial task. */
7457 cred_init_security();
7458
7459 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7460 if (!default_noexec)
7461 pr_notice("SELinux: virtual memory is executable by default\n");
7462
7463 avc_init();
7464
7465 avtab_cache_init();
7466
7467 ebitmap_cache_init();
7468
7469 hashtab_cache_init();
7470
7471 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
7472 &selinux_lsmid);
7473
7474 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7475 panic("SELinux: Unable to register AVC netcache callback\n");
7476
7477 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7478 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7479
7480 if (selinux_enforcing_boot)
7481 pr_debug("SELinux: Starting in enforcing mode\n");
7482 else
7483 pr_debug("SELinux: Starting in permissive mode\n");
7484
7485 fs_validate_description("selinux", selinux_fs_parameters);
7486
7487 return 0;
7488 }
7489
delayed_superblock_init(struct super_block * sb,void * unused)7490 static void delayed_superblock_init(struct super_block *sb, void *unused)
7491 {
7492 selinux_set_mnt_opts(sb, NULL, 0, NULL);
7493 }
7494
selinux_complete_init(void)7495 void selinux_complete_init(void)
7496 {
7497 pr_debug("SELinux: Completing initialization.\n");
7498
7499 /* Set up any superblocks initialized prior to the policy load. */
7500 pr_debug("SELinux: Setting up existing superblocks.\n");
7501 iterate_supers(delayed_superblock_init, NULL);
7502 }
7503
7504 /* SELinux requires early initialization in order to label
7505 all processes and objects when they are created. */
7506 DEFINE_LSM(selinux) = {
7507 .name = "selinux",
7508 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7509 .enabled = &selinux_enabled_boot,
7510 .blobs = &selinux_blob_sizes,
7511 .init = selinux_init,
7512 };
7513
7514 #if defined(CONFIG_NETFILTER)
7515 static const struct nf_hook_ops selinux_nf_ops[] = {
7516 {
7517 .hook = selinux_ip_postroute,
7518 .pf = NFPROTO_IPV4,
7519 .hooknum = NF_INET_POST_ROUTING,
7520 .priority = NF_IP_PRI_SELINUX_LAST,
7521 },
7522 {
7523 .hook = selinux_ip_forward,
7524 .pf = NFPROTO_IPV4,
7525 .hooknum = NF_INET_FORWARD,
7526 .priority = NF_IP_PRI_SELINUX_FIRST,
7527 },
7528 {
7529 .hook = selinux_ip_output,
7530 .pf = NFPROTO_IPV4,
7531 .hooknum = NF_INET_LOCAL_OUT,
7532 .priority = NF_IP_PRI_SELINUX_FIRST,
7533 },
7534 #if IS_ENABLED(CONFIG_IPV6)
7535 {
7536 .hook = selinux_ip_postroute,
7537 .pf = NFPROTO_IPV6,
7538 .hooknum = NF_INET_POST_ROUTING,
7539 .priority = NF_IP6_PRI_SELINUX_LAST,
7540 },
7541 {
7542 .hook = selinux_ip_forward,
7543 .pf = NFPROTO_IPV6,
7544 .hooknum = NF_INET_FORWARD,
7545 .priority = NF_IP6_PRI_SELINUX_FIRST,
7546 },
7547 {
7548 .hook = selinux_ip_output,
7549 .pf = NFPROTO_IPV6,
7550 .hooknum = NF_INET_LOCAL_OUT,
7551 .priority = NF_IP6_PRI_SELINUX_FIRST,
7552 },
7553 #endif /* IPV6 */
7554 };
7555
selinux_nf_register(struct net * net)7556 static int __net_init selinux_nf_register(struct net *net)
7557 {
7558 return nf_register_net_hooks(net, selinux_nf_ops,
7559 ARRAY_SIZE(selinux_nf_ops));
7560 }
7561
selinux_nf_unregister(struct net * net)7562 static void __net_exit selinux_nf_unregister(struct net *net)
7563 {
7564 nf_unregister_net_hooks(net, selinux_nf_ops,
7565 ARRAY_SIZE(selinux_nf_ops));
7566 }
7567
7568 static struct pernet_operations selinux_net_ops = {
7569 .init = selinux_nf_register,
7570 .exit = selinux_nf_unregister,
7571 };
7572
selinux_nf_ip_init(void)7573 static int __init selinux_nf_ip_init(void)
7574 {
7575 int err;
7576
7577 if (!selinux_enabled_boot)
7578 return 0;
7579
7580 pr_debug("SELinux: Registering netfilter hooks\n");
7581
7582 err = register_pernet_subsys(&selinux_net_ops);
7583 if (err)
7584 panic("SELinux: register_pernet_subsys: error %d\n", err);
7585
7586 return 0;
7587 }
7588 __initcall(selinux_nf_ip_init);
7589 #endif /* CONFIG_NETFILTER */
7590