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 case FSNOTIFY_OBJ_TYPE_MNTNS:
3399 perm = FILE__WATCH_MOUNTNS;
3400 break;
3401 default:
3402 return -EINVAL;
3403 }
3404
3405 /* blocking watches require the file:watch_with_perm permission */
3406 if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3407 perm |= FILE__WATCH_WITH_PERM;
3408
3409 /* watches on read-like events need the file:watch_reads permission */
3410 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_PRE_ACCESS |
3411 FS_CLOSE_NOWRITE))
3412 perm |= FILE__WATCH_READS;
3413
3414 return path_has_perm(current_cred(), path, perm);
3415 }
3416
3417 /*
3418 * Copy the inode security context value to the user.
3419 *
3420 * Permission check is handled by selinux_inode_getxattr hook.
3421 */
selinux_inode_getsecurity(struct mnt_idmap * idmap,struct inode * inode,const char * name,void ** buffer,bool alloc)3422 static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3423 struct inode *inode, const char *name,
3424 void **buffer, bool alloc)
3425 {
3426 u32 size;
3427 int error;
3428 char *context = NULL;
3429 struct inode_security_struct *isec;
3430
3431 /*
3432 * If we're not initialized yet, then we can't validate contexts, so
3433 * just let vfs_getxattr fall back to using the on-disk xattr.
3434 */
3435 if (!selinux_initialized() ||
3436 strcmp(name, XATTR_SELINUX_SUFFIX))
3437 return -EOPNOTSUPP;
3438
3439 /*
3440 * If the caller has CAP_MAC_ADMIN, then get the raw context
3441 * value even if it is not defined by current policy; otherwise,
3442 * use the in-core value under current policy.
3443 * Use the non-auditing forms of the permission checks since
3444 * getxattr may be called by unprivileged processes commonly
3445 * and lack of permission just means that we fall back to the
3446 * in-core context value, not a denial.
3447 */
3448 isec = inode_security(inode);
3449 if (has_cap_mac_admin(false))
3450 error = security_sid_to_context_force(isec->sid, &context,
3451 &size);
3452 else
3453 error = security_sid_to_context(isec->sid,
3454 &context, &size);
3455 if (error)
3456 return error;
3457 error = size;
3458 if (alloc) {
3459 *buffer = context;
3460 goto out_nofree;
3461 }
3462 kfree(context);
3463 out_nofree:
3464 return error;
3465 }
3466
selinux_inode_setsecurity(struct inode * inode,const char * name,const void * value,size_t size,int flags)3467 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3468 const void *value, size_t size, int flags)
3469 {
3470 struct inode_security_struct *isec = inode_security_novalidate(inode);
3471 struct superblock_security_struct *sbsec;
3472 u32 newsid;
3473 int rc;
3474
3475 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3476 return -EOPNOTSUPP;
3477
3478 sbsec = selinux_superblock(inode->i_sb);
3479 if (!(sbsec->flags & SBLABEL_MNT))
3480 return -EOPNOTSUPP;
3481
3482 if (!value || !size)
3483 return -EACCES;
3484
3485 rc = security_context_to_sid(value, size, &newsid,
3486 GFP_KERNEL);
3487 if (rc)
3488 return rc;
3489
3490 spin_lock(&isec->lock);
3491 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3492 isec->sid = newsid;
3493 isec->initialized = LABEL_INITIALIZED;
3494 spin_unlock(&isec->lock);
3495 return 0;
3496 }
3497
selinux_inode_listsecurity(struct inode * inode,char * buffer,size_t buffer_size)3498 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3499 {
3500 const int len = sizeof(XATTR_NAME_SELINUX);
3501
3502 if (!selinux_initialized())
3503 return 0;
3504
3505 if (buffer && len <= buffer_size)
3506 memcpy(buffer, XATTR_NAME_SELINUX, len);
3507 return len;
3508 }
3509
selinux_inode_getlsmprop(struct inode * inode,struct lsm_prop * prop)3510 static void selinux_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop)
3511 {
3512 struct inode_security_struct *isec = inode_security_novalidate(inode);
3513
3514 prop->selinux.secid = isec->sid;
3515 }
3516
selinux_inode_copy_up(struct dentry * src,struct cred ** new)3517 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3518 {
3519 struct lsm_prop prop;
3520 struct task_security_struct *tsec;
3521 struct cred *new_creds = *new;
3522
3523 if (new_creds == NULL) {
3524 new_creds = prepare_creds();
3525 if (!new_creds)
3526 return -ENOMEM;
3527 }
3528
3529 tsec = selinux_cred(new_creds);
3530 /* Get label from overlay inode and set it in create_sid */
3531 selinux_inode_getlsmprop(d_inode(src), &prop);
3532 tsec->create_sid = prop.selinux.secid;
3533 *new = new_creds;
3534 return 0;
3535 }
3536
selinux_inode_copy_up_xattr(struct dentry * dentry,const char * name)3537 static int selinux_inode_copy_up_xattr(struct dentry *dentry, const char *name)
3538 {
3539 /* The copy_up hook above sets the initial context on an inode, but we
3540 * don't then want to overwrite it by blindly copying all the lower
3541 * xattrs up. Instead, filter out SELinux-related xattrs following
3542 * policy load.
3543 */
3544 if (selinux_initialized() && !strcmp(name, XATTR_NAME_SELINUX))
3545 return -ECANCELED; /* Discard */
3546 /*
3547 * Any other attribute apart from SELINUX is not claimed, supported
3548 * by selinux.
3549 */
3550 return -EOPNOTSUPP;
3551 }
3552
3553 /* kernfs node operations */
3554
selinux_kernfs_init_security(struct kernfs_node * kn_dir,struct kernfs_node * kn)3555 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3556 struct kernfs_node *kn)
3557 {
3558 const struct task_security_struct *tsec = selinux_cred(current_cred());
3559 u32 parent_sid, newsid, clen;
3560 int rc;
3561 char *context;
3562
3563 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3564 if (rc == -ENODATA)
3565 return 0;
3566 else if (rc < 0)
3567 return rc;
3568
3569 clen = (u32)rc;
3570 context = kmalloc(clen, GFP_KERNEL);
3571 if (!context)
3572 return -ENOMEM;
3573
3574 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3575 if (rc < 0) {
3576 kfree(context);
3577 return rc;
3578 }
3579
3580 rc = security_context_to_sid(context, clen, &parent_sid,
3581 GFP_KERNEL);
3582 kfree(context);
3583 if (rc)
3584 return rc;
3585
3586 if (tsec->create_sid) {
3587 newsid = tsec->create_sid;
3588 } else {
3589 u16 secclass = inode_mode_to_security_class(kn->mode);
3590 const char *kn_name;
3591 struct qstr q;
3592
3593 /* kn is fresh, can't be renamed, name goes not away */
3594 kn_name = rcu_dereference_check(kn->name, true);
3595 q.name = kn_name;
3596 q.hash_len = hashlen_string(kn_dir, kn_name);
3597
3598 rc = security_transition_sid(tsec->sid,
3599 parent_sid, secclass, &q,
3600 &newsid);
3601 if (rc)
3602 return rc;
3603 }
3604
3605 rc = security_sid_to_context_force(newsid,
3606 &context, &clen);
3607 if (rc)
3608 return rc;
3609
3610 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3611 XATTR_CREATE);
3612 kfree(context);
3613 return rc;
3614 }
3615
3616
3617 /* file security operations */
3618
selinux_revalidate_file_permission(struct file * file,int mask)3619 static int selinux_revalidate_file_permission(struct file *file, int mask)
3620 {
3621 const struct cred *cred = current_cred();
3622 struct inode *inode = file_inode(file);
3623
3624 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3625 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3626 mask |= MAY_APPEND;
3627
3628 return file_has_perm(cred, file,
3629 file_mask_to_av(inode->i_mode, mask));
3630 }
3631
selinux_file_permission(struct file * file,int mask)3632 static int selinux_file_permission(struct file *file, int mask)
3633 {
3634 struct inode *inode = file_inode(file);
3635 struct file_security_struct *fsec = selinux_file(file);
3636 struct inode_security_struct *isec;
3637 u32 sid = current_sid();
3638
3639 if (!mask)
3640 /* No permission to check. Existence test. */
3641 return 0;
3642
3643 isec = inode_security(inode);
3644 if (sid == fsec->sid && fsec->isid == isec->sid &&
3645 fsec->pseqno == avc_policy_seqno())
3646 /* No change since file_open check. */
3647 return 0;
3648
3649 return selinux_revalidate_file_permission(file, mask);
3650 }
3651
selinux_file_alloc_security(struct file * file)3652 static int selinux_file_alloc_security(struct file *file)
3653 {
3654 struct file_security_struct *fsec = selinux_file(file);
3655 u32 sid = current_sid();
3656
3657 fsec->sid = sid;
3658 fsec->fown_sid = sid;
3659
3660 return 0;
3661 }
3662
3663 /*
3664 * Check whether a task has the ioctl permission and cmd
3665 * operation to an inode.
3666 */
ioctl_has_perm(const struct cred * cred,struct file * file,u32 requested,u16 cmd)3667 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3668 u32 requested, u16 cmd)
3669 {
3670 struct common_audit_data ad;
3671 struct file_security_struct *fsec = selinux_file(file);
3672 struct inode *inode = file_inode(file);
3673 struct inode_security_struct *isec;
3674 struct lsm_ioctlop_audit ioctl;
3675 u32 ssid = cred_sid(cred);
3676 int rc;
3677 u8 driver = cmd >> 8;
3678 u8 xperm = cmd & 0xff;
3679
3680 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3681 ad.u.op = &ioctl;
3682 ad.u.op->cmd = cmd;
3683 ad.u.op->path = file->f_path;
3684
3685 if (ssid != fsec->sid) {
3686 rc = avc_has_perm(ssid, fsec->sid,
3687 SECCLASS_FD,
3688 FD__USE,
3689 &ad);
3690 if (rc)
3691 goto out;
3692 }
3693
3694 if (unlikely(IS_PRIVATE(inode)))
3695 return 0;
3696
3697 isec = inode_security(inode);
3698 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, requested,
3699 driver, AVC_EXT_IOCTL, xperm, &ad);
3700 out:
3701 return rc;
3702 }
3703
selinux_file_ioctl(struct file * file,unsigned int cmd,unsigned long arg)3704 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3705 unsigned long arg)
3706 {
3707 const struct cred *cred = current_cred();
3708 int error = 0;
3709
3710 switch (cmd) {
3711 case FIONREAD:
3712 case FIBMAP:
3713 case FIGETBSZ:
3714 case FS_IOC_GETFLAGS:
3715 case FS_IOC_GETVERSION:
3716 error = file_has_perm(cred, file, FILE__GETATTR);
3717 break;
3718
3719 case FS_IOC_SETFLAGS:
3720 case FS_IOC_SETVERSION:
3721 error = file_has_perm(cred, file, FILE__SETATTR);
3722 break;
3723
3724 /* sys_ioctl() checks */
3725 case FIONBIO:
3726 case FIOASYNC:
3727 error = file_has_perm(cred, file, 0);
3728 break;
3729
3730 case KDSKBENT:
3731 case KDSKBSENT:
3732 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3733 CAP_OPT_NONE, true);
3734 break;
3735
3736 case FIOCLEX:
3737 case FIONCLEX:
3738 if (!selinux_policycap_ioctl_skip_cloexec())
3739 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3740 break;
3741
3742 /* default case assumes that the command will go
3743 * to the file's ioctl() function.
3744 */
3745 default:
3746 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3747 }
3748 return error;
3749 }
3750
selinux_file_ioctl_compat(struct file * file,unsigned int cmd,unsigned long arg)3751 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd,
3752 unsigned long arg)
3753 {
3754 /*
3755 * If we are in a 64-bit kernel running 32-bit userspace, we need to
3756 * make sure we don't compare 32-bit flags to 64-bit flags.
3757 */
3758 switch (cmd) {
3759 case FS_IOC32_GETFLAGS:
3760 cmd = FS_IOC_GETFLAGS;
3761 break;
3762 case FS_IOC32_SETFLAGS:
3763 cmd = FS_IOC_SETFLAGS;
3764 break;
3765 case FS_IOC32_GETVERSION:
3766 cmd = FS_IOC_GETVERSION;
3767 break;
3768 case FS_IOC32_SETVERSION:
3769 cmd = FS_IOC_SETVERSION;
3770 break;
3771 default:
3772 break;
3773 }
3774
3775 return selinux_file_ioctl(file, cmd, arg);
3776 }
3777
3778 static int default_noexec __ro_after_init;
3779
file_map_prot_check(struct file * file,unsigned long prot,int shared)3780 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3781 {
3782 const struct cred *cred = current_cred();
3783 u32 sid = cred_sid(cred);
3784 int rc = 0;
3785
3786 if (default_noexec &&
3787 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3788 (!shared && (prot & PROT_WRITE)))) {
3789 /*
3790 * We are making executable an anonymous mapping or a
3791 * private file mapping that will also be writable.
3792 * This has an additional check.
3793 */
3794 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3795 PROCESS__EXECMEM, NULL);
3796 if (rc)
3797 goto error;
3798 }
3799
3800 if (file) {
3801 /* read access is always possible with a mapping */
3802 u32 av = FILE__READ;
3803
3804 /* write access only matters if the mapping is shared */
3805 if (shared && (prot & PROT_WRITE))
3806 av |= FILE__WRITE;
3807
3808 if (prot & PROT_EXEC)
3809 av |= FILE__EXECUTE;
3810
3811 return file_has_perm(cred, file, av);
3812 }
3813
3814 error:
3815 return rc;
3816 }
3817
selinux_mmap_addr(unsigned long addr)3818 static int selinux_mmap_addr(unsigned long addr)
3819 {
3820 int rc = 0;
3821
3822 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3823 u32 sid = current_sid();
3824 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3825 MEMPROTECT__MMAP_ZERO, NULL);
3826 }
3827
3828 return rc;
3829 }
3830
selinux_mmap_file(struct file * file,unsigned long reqprot __always_unused,unsigned long prot,unsigned long flags)3831 static int selinux_mmap_file(struct file *file,
3832 unsigned long reqprot __always_unused,
3833 unsigned long prot, unsigned long flags)
3834 {
3835 struct common_audit_data ad;
3836 int rc;
3837
3838 if (file) {
3839 ad.type = LSM_AUDIT_DATA_FILE;
3840 ad.u.file = file;
3841 rc = inode_has_perm(current_cred(), file_inode(file),
3842 FILE__MAP, &ad);
3843 if (rc)
3844 return rc;
3845 }
3846
3847 return file_map_prot_check(file, prot,
3848 (flags & MAP_TYPE) == MAP_SHARED);
3849 }
3850
selinux_file_mprotect(struct vm_area_struct * vma,unsigned long reqprot __always_unused,unsigned long prot)3851 static int selinux_file_mprotect(struct vm_area_struct *vma,
3852 unsigned long reqprot __always_unused,
3853 unsigned long prot)
3854 {
3855 const struct cred *cred = current_cred();
3856 u32 sid = cred_sid(cred);
3857
3858 if (default_noexec &&
3859 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3860 int rc = 0;
3861 /*
3862 * We don't use the vma_is_initial_heap() helper as it has
3863 * a history of problems and is currently broken on systems
3864 * where there is no heap, e.g. brk == start_brk. Before
3865 * replacing the conditional below with vma_is_initial_heap(),
3866 * or something similar, please ensure that the logic is the
3867 * same as what we have below or you have tested every possible
3868 * corner case you can think to test.
3869 */
3870 if (vma->vm_start >= vma->vm_mm->start_brk &&
3871 vma->vm_end <= vma->vm_mm->brk) {
3872 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3873 PROCESS__EXECHEAP, NULL);
3874 } else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
3875 vma_is_stack_for_current(vma))) {
3876 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3877 PROCESS__EXECSTACK, NULL);
3878 } else if (vma->vm_file && vma->anon_vma) {
3879 /*
3880 * We are making executable a file mapping that has
3881 * had some COW done. Since pages might have been
3882 * written, check ability to execute the possibly
3883 * modified content. This typically should only
3884 * occur for text relocations.
3885 */
3886 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3887 }
3888 if (rc)
3889 return rc;
3890 }
3891
3892 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3893 }
3894
selinux_file_lock(struct file * file,unsigned int cmd)3895 static int selinux_file_lock(struct file *file, unsigned int cmd)
3896 {
3897 const struct cred *cred = current_cred();
3898
3899 return file_has_perm(cred, file, FILE__LOCK);
3900 }
3901
selinux_file_fcntl(struct file * file,unsigned int cmd,unsigned long arg)3902 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3903 unsigned long arg)
3904 {
3905 const struct cred *cred = current_cred();
3906 int err = 0;
3907
3908 switch (cmd) {
3909 case F_SETFL:
3910 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3911 err = file_has_perm(cred, file, FILE__WRITE);
3912 break;
3913 }
3914 fallthrough;
3915 case F_SETOWN:
3916 case F_SETSIG:
3917 case F_GETFL:
3918 case F_GETOWN:
3919 case F_GETSIG:
3920 case F_GETOWNER_UIDS:
3921 /* Just check FD__USE permission */
3922 err = file_has_perm(cred, file, 0);
3923 break;
3924 case F_GETLK:
3925 case F_SETLK:
3926 case F_SETLKW:
3927 case F_OFD_GETLK:
3928 case F_OFD_SETLK:
3929 case F_OFD_SETLKW:
3930 #if BITS_PER_LONG == 32
3931 case F_GETLK64:
3932 case F_SETLK64:
3933 case F_SETLKW64:
3934 #endif
3935 err = file_has_perm(cred, file, FILE__LOCK);
3936 break;
3937 }
3938
3939 return err;
3940 }
3941
selinux_file_set_fowner(struct file * file)3942 static void selinux_file_set_fowner(struct file *file)
3943 {
3944 struct file_security_struct *fsec;
3945
3946 fsec = selinux_file(file);
3947 fsec->fown_sid = current_sid();
3948 }
3949
selinux_file_send_sigiotask(struct task_struct * tsk,struct fown_struct * fown,int signum)3950 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3951 struct fown_struct *fown, int signum)
3952 {
3953 struct file *file;
3954 u32 sid = task_sid_obj(tsk);
3955 u32 perm;
3956 struct file_security_struct *fsec;
3957
3958 /* struct fown_struct is never outside the context of a struct file */
3959 file = fown->file;
3960
3961 fsec = selinux_file(file);
3962
3963 if (!signum)
3964 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3965 else
3966 perm = signal_to_av(signum);
3967
3968 return avc_has_perm(fsec->fown_sid, sid,
3969 SECCLASS_PROCESS, perm, NULL);
3970 }
3971
selinux_file_receive(struct file * file)3972 static int selinux_file_receive(struct file *file)
3973 {
3974 const struct cred *cred = current_cred();
3975
3976 return file_has_perm(cred, file, file_to_av(file));
3977 }
3978
selinux_file_open(struct file * file)3979 static int selinux_file_open(struct file *file)
3980 {
3981 struct file_security_struct *fsec;
3982 struct inode_security_struct *isec;
3983
3984 fsec = selinux_file(file);
3985 isec = inode_security(file_inode(file));
3986 /*
3987 * Save inode label and policy sequence number
3988 * at open-time so that selinux_file_permission
3989 * can determine whether revalidation is necessary.
3990 * Task label is already saved in the file security
3991 * struct as its SID.
3992 */
3993 fsec->isid = isec->sid;
3994 fsec->pseqno = avc_policy_seqno();
3995 /*
3996 * Since the inode label or policy seqno may have changed
3997 * between the selinux_inode_permission check and the saving
3998 * of state above, recheck that access is still permitted.
3999 * Otherwise, access might never be revalidated against the
4000 * new inode label or new policy.
4001 * This check is not redundant - do not remove.
4002 */
4003 return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
4004 }
4005
4006 /* task security operations */
4007
selinux_task_alloc(struct task_struct * task,unsigned long clone_flags)4008 static int selinux_task_alloc(struct task_struct *task,
4009 unsigned long clone_flags)
4010 {
4011 u32 sid = current_sid();
4012
4013 return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
4014 }
4015
4016 /*
4017 * prepare a new set of credentials for modification
4018 */
selinux_cred_prepare(struct cred * new,const struct cred * old,gfp_t gfp)4019 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
4020 gfp_t gfp)
4021 {
4022 const struct task_security_struct *old_tsec = selinux_cred(old);
4023 struct task_security_struct *tsec = selinux_cred(new);
4024
4025 *tsec = *old_tsec;
4026 return 0;
4027 }
4028
4029 /*
4030 * transfer the SELinux data to a blank set of creds
4031 */
selinux_cred_transfer(struct cred * new,const struct cred * old)4032 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4033 {
4034 const struct task_security_struct *old_tsec = selinux_cred(old);
4035 struct task_security_struct *tsec = selinux_cred(new);
4036
4037 *tsec = *old_tsec;
4038 }
4039
selinux_cred_getsecid(const struct cred * c,u32 * secid)4040 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4041 {
4042 *secid = cred_sid(c);
4043 }
4044
selinux_cred_getlsmprop(const struct cred * c,struct lsm_prop * prop)4045 static void selinux_cred_getlsmprop(const struct cred *c, struct lsm_prop *prop)
4046 {
4047 prop->selinux.secid = cred_sid(c);
4048 }
4049
4050 /*
4051 * set the security data for a kernel service
4052 * - all the creation contexts are set to unlabelled
4053 */
selinux_kernel_act_as(struct cred * new,u32 secid)4054 static int selinux_kernel_act_as(struct cred *new, u32 secid)
4055 {
4056 struct task_security_struct *tsec = selinux_cred(new);
4057 u32 sid = current_sid();
4058 int ret;
4059
4060 ret = avc_has_perm(sid, secid,
4061 SECCLASS_KERNEL_SERVICE,
4062 KERNEL_SERVICE__USE_AS_OVERRIDE,
4063 NULL);
4064 if (ret == 0) {
4065 tsec->sid = secid;
4066 tsec->create_sid = 0;
4067 tsec->keycreate_sid = 0;
4068 tsec->sockcreate_sid = 0;
4069 }
4070 return ret;
4071 }
4072
4073 /*
4074 * set the file creation context in a security record to the same as the
4075 * objective context of the specified inode
4076 */
selinux_kernel_create_files_as(struct cred * new,struct inode * inode)4077 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4078 {
4079 struct inode_security_struct *isec = inode_security(inode);
4080 struct task_security_struct *tsec = selinux_cred(new);
4081 u32 sid = current_sid();
4082 int ret;
4083
4084 ret = avc_has_perm(sid, isec->sid,
4085 SECCLASS_KERNEL_SERVICE,
4086 KERNEL_SERVICE__CREATE_FILES_AS,
4087 NULL);
4088
4089 if (ret == 0)
4090 tsec->create_sid = isec->sid;
4091 return ret;
4092 }
4093
selinux_kernel_module_request(char * kmod_name)4094 static int selinux_kernel_module_request(char *kmod_name)
4095 {
4096 struct common_audit_data ad;
4097
4098 ad.type = LSM_AUDIT_DATA_KMOD;
4099 ad.u.kmod_name = kmod_name;
4100
4101 return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4102 SYSTEM__MODULE_REQUEST, &ad);
4103 }
4104
selinux_kernel_load_from_file(struct file * file,u32 requested)4105 static int selinux_kernel_load_from_file(struct file *file, u32 requested)
4106 {
4107 struct common_audit_data ad;
4108 struct inode_security_struct *isec;
4109 struct file_security_struct *fsec;
4110 u32 sid = current_sid();
4111 int rc;
4112
4113 if (file == NULL)
4114 return avc_has_perm(sid, sid, SECCLASS_SYSTEM, requested, NULL);
4115
4116 ad.type = LSM_AUDIT_DATA_FILE;
4117 ad.u.file = file;
4118
4119 fsec = selinux_file(file);
4120 if (sid != fsec->sid) {
4121 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4122 if (rc)
4123 return rc;
4124 }
4125
4126 isec = inode_security(file_inode(file));
4127 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, requested, &ad);
4128 }
4129
selinux_kernel_read_file(struct file * file,enum kernel_read_file_id id,bool contents)4130 static int selinux_kernel_read_file(struct file *file,
4131 enum kernel_read_file_id id,
4132 bool contents)
4133 {
4134 int rc = 0;
4135
4136 BUILD_BUG_ON_MSG(READING_MAX_ID > 7,
4137 "New kernel_read_file_id introduced; update SELinux!");
4138
4139 switch (id) {
4140 case READING_FIRMWARE:
4141 rc = selinux_kernel_load_from_file(file, SYSTEM__FIRMWARE_LOAD);
4142 break;
4143 case READING_MODULE:
4144 rc = selinux_kernel_load_from_file(file, SYSTEM__MODULE_LOAD);
4145 break;
4146 case READING_KEXEC_IMAGE:
4147 rc = selinux_kernel_load_from_file(file,
4148 SYSTEM__KEXEC_IMAGE_LOAD);
4149 break;
4150 case READING_KEXEC_INITRAMFS:
4151 rc = selinux_kernel_load_from_file(file,
4152 SYSTEM__KEXEC_INITRAMFS_LOAD);
4153 break;
4154 case READING_POLICY:
4155 rc = selinux_kernel_load_from_file(file, SYSTEM__POLICY_LOAD);
4156 break;
4157 case READING_X509_CERTIFICATE:
4158 rc = selinux_kernel_load_from_file(file,
4159 SYSTEM__X509_CERTIFICATE_LOAD);
4160 break;
4161 default:
4162 break;
4163 }
4164
4165 return rc;
4166 }
4167
selinux_kernel_load_data(enum kernel_load_data_id id,bool contents)4168 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4169 {
4170 int rc = 0;
4171
4172 BUILD_BUG_ON_MSG(LOADING_MAX_ID > 7,
4173 "New kernel_load_data_id introduced; update SELinux!");
4174
4175 switch (id) {
4176 case LOADING_FIRMWARE:
4177 rc = selinux_kernel_load_from_file(NULL, SYSTEM__FIRMWARE_LOAD);
4178 break;
4179 case LOADING_MODULE:
4180 rc = selinux_kernel_load_from_file(NULL, SYSTEM__MODULE_LOAD);
4181 break;
4182 case LOADING_KEXEC_IMAGE:
4183 rc = selinux_kernel_load_from_file(NULL,
4184 SYSTEM__KEXEC_IMAGE_LOAD);
4185 break;
4186 case LOADING_KEXEC_INITRAMFS:
4187 rc = selinux_kernel_load_from_file(NULL,
4188 SYSTEM__KEXEC_INITRAMFS_LOAD);
4189 break;
4190 case LOADING_POLICY:
4191 rc = selinux_kernel_load_from_file(NULL,
4192 SYSTEM__POLICY_LOAD);
4193 break;
4194 case LOADING_X509_CERTIFICATE:
4195 rc = selinux_kernel_load_from_file(NULL,
4196 SYSTEM__X509_CERTIFICATE_LOAD);
4197 break;
4198 default:
4199 break;
4200 }
4201
4202 return rc;
4203 }
4204
selinux_task_setpgid(struct task_struct * p,pid_t pgid)4205 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4206 {
4207 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4208 PROCESS__SETPGID, NULL);
4209 }
4210
selinux_task_getpgid(struct task_struct * p)4211 static int selinux_task_getpgid(struct task_struct *p)
4212 {
4213 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4214 PROCESS__GETPGID, NULL);
4215 }
4216
selinux_task_getsid(struct task_struct * p)4217 static int selinux_task_getsid(struct task_struct *p)
4218 {
4219 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4220 PROCESS__GETSESSION, NULL);
4221 }
4222
selinux_current_getlsmprop_subj(struct lsm_prop * prop)4223 static void selinux_current_getlsmprop_subj(struct lsm_prop *prop)
4224 {
4225 prop->selinux.secid = current_sid();
4226 }
4227
selinux_task_getlsmprop_obj(struct task_struct * p,struct lsm_prop * prop)4228 static void selinux_task_getlsmprop_obj(struct task_struct *p,
4229 struct lsm_prop *prop)
4230 {
4231 prop->selinux.secid = task_sid_obj(p);
4232 }
4233
selinux_task_setnice(struct task_struct * p,int nice)4234 static int selinux_task_setnice(struct task_struct *p, int nice)
4235 {
4236 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4237 PROCESS__SETSCHED, NULL);
4238 }
4239
selinux_task_setioprio(struct task_struct * p,int ioprio)4240 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4241 {
4242 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4243 PROCESS__SETSCHED, NULL);
4244 }
4245
selinux_task_getioprio(struct task_struct * p)4246 static int selinux_task_getioprio(struct task_struct *p)
4247 {
4248 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4249 PROCESS__GETSCHED, NULL);
4250 }
4251
selinux_task_prlimit(const struct cred * cred,const struct cred * tcred,unsigned int flags)4252 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4253 unsigned int flags)
4254 {
4255 u32 av = 0;
4256
4257 if (!flags)
4258 return 0;
4259 if (flags & LSM_PRLIMIT_WRITE)
4260 av |= PROCESS__SETRLIMIT;
4261 if (flags & LSM_PRLIMIT_READ)
4262 av |= PROCESS__GETRLIMIT;
4263 return avc_has_perm(cred_sid(cred), cred_sid(tcred),
4264 SECCLASS_PROCESS, av, NULL);
4265 }
4266
selinux_task_setrlimit(struct task_struct * p,unsigned int resource,struct rlimit * new_rlim)4267 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4268 struct rlimit *new_rlim)
4269 {
4270 struct rlimit *old_rlim = p->signal->rlim + resource;
4271
4272 /* Control the ability to change the hard limit (whether
4273 lowering or raising it), so that the hard limit can
4274 later be used as a safe reset point for the soft limit
4275 upon context transitions. See selinux_bprm_committing_creds. */
4276 if (old_rlim->rlim_max != new_rlim->rlim_max)
4277 return avc_has_perm(current_sid(), task_sid_obj(p),
4278 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4279
4280 return 0;
4281 }
4282
selinux_task_setscheduler(struct task_struct * p)4283 static int selinux_task_setscheduler(struct task_struct *p)
4284 {
4285 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4286 PROCESS__SETSCHED, NULL);
4287 }
4288
selinux_task_getscheduler(struct task_struct * p)4289 static int selinux_task_getscheduler(struct task_struct *p)
4290 {
4291 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4292 PROCESS__GETSCHED, NULL);
4293 }
4294
selinux_task_movememory(struct task_struct * p)4295 static int selinux_task_movememory(struct task_struct *p)
4296 {
4297 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4298 PROCESS__SETSCHED, NULL);
4299 }
4300
selinux_task_kill(struct task_struct * p,struct kernel_siginfo * info,int sig,const struct cred * cred)4301 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4302 int sig, const struct cred *cred)
4303 {
4304 u32 secid;
4305 u32 perm;
4306
4307 if (!sig)
4308 perm = PROCESS__SIGNULL; /* null signal; existence test */
4309 else
4310 perm = signal_to_av(sig);
4311 if (!cred)
4312 secid = current_sid();
4313 else
4314 secid = cred_sid(cred);
4315 return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4316 }
4317
selinux_task_to_inode(struct task_struct * p,struct inode * inode)4318 static void selinux_task_to_inode(struct task_struct *p,
4319 struct inode *inode)
4320 {
4321 struct inode_security_struct *isec = selinux_inode(inode);
4322 u32 sid = task_sid_obj(p);
4323
4324 spin_lock(&isec->lock);
4325 isec->sclass = inode_mode_to_security_class(inode->i_mode);
4326 isec->sid = sid;
4327 isec->initialized = LABEL_INITIALIZED;
4328 spin_unlock(&isec->lock);
4329 }
4330
selinux_userns_create(const struct cred * cred)4331 static int selinux_userns_create(const struct cred *cred)
4332 {
4333 u32 sid = current_sid();
4334
4335 return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4336 USER_NAMESPACE__CREATE, NULL);
4337 }
4338
4339 /* Returns error only if unable to parse addresses */
selinux_parse_skb_ipv4(struct sk_buff * skb,struct common_audit_data * ad,u8 * proto)4340 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4341 struct common_audit_data *ad, u8 *proto)
4342 {
4343 int offset, ihlen, ret = -EINVAL;
4344 struct iphdr _iph, *ih;
4345
4346 offset = skb_network_offset(skb);
4347 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4348 if (ih == NULL)
4349 goto out;
4350
4351 ihlen = ih->ihl * 4;
4352 if (ihlen < sizeof(_iph))
4353 goto out;
4354
4355 ad->u.net->v4info.saddr = ih->saddr;
4356 ad->u.net->v4info.daddr = ih->daddr;
4357 ret = 0;
4358
4359 if (proto)
4360 *proto = ih->protocol;
4361
4362 switch (ih->protocol) {
4363 case IPPROTO_TCP: {
4364 struct tcphdr _tcph, *th;
4365
4366 if (ntohs(ih->frag_off) & IP_OFFSET)
4367 break;
4368
4369 offset += ihlen;
4370 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4371 if (th == NULL)
4372 break;
4373
4374 ad->u.net->sport = th->source;
4375 ad->u.net->dport = th->dest;
4376 break;
4377 }
4378
4379 case IPPROTO_UDP: {
4380 struct udphdr _udph, *uh;
4381
4382 if (ntohs(ih->frag_off) & IP_OFFSET)
4383 break;
4384
4385 offset += ihlen;
4386 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4387 if (uh == NULL)
4388 break;
4389
4390 ad->u.net->sport = uh->source;
4391 ad->u.net->dport = uh->dest;
4392 break;
4393 }
4394
4395 case IPPROTO_DCCP: {
4396 struct dccp_hdr _dccph, *dh;
4397
4398 if (ntohs(ih->frag_off) & IP_OFFSET)
4399 break;
4400
4401 offset += ihlen;
4402 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4403 if (dh == NULL)
4404 break;
4405
4406 ad->u.net->sport = dh->dccph_sport;
4407 ad->u.net->dport = dh->dccph_dport;
4408 break;
4409 }
4410
4411 #if IS_ENABLED(CONFIG_IP_SCTP)
4412 case IPPROTO_SCTP: {
4413 struct sctphdr _sctph, *sh;
4414
4415 if (ntohs(ih->frag_off) & IP_OFFSET)
4416 break;
4417
4418 offset += ihlen;
4419 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4420 if (sh == NULL)
4421 break;
4422
4423 ad->u.net->sport = sh->source;
4424 ad->u.net->dport = sh->dest;
4425 break;
4426 }
4427 #endif
4428 default:
4429 break;
4430 }
4431 out:
4432 return ret;
4433 }
4434
4435 #if IS_ENABLED(CONFIG_IPV6)
4436
4437 /* Returns error only if unable to parse addresses */
selinux_parse_skb_ipv6(struct sk_buff * skb,struct common_audit_data * ad,u8 * proto)4438 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4439 struct common_audit_data *ad, u8 *proto)
4440 {
4441 u8 nexthdr;
4442 int ret = -EINVAL, offset;
4443 struct ipv6hdr _ipv6h, *ip6;
4444 __be16 frag_off;
4445
4446 offset = skb_network_offset(skb);
4447 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4448 if (ip6 == NULL)
4449 goto out;
4450
4451 ad->u.net->v6info.saddr = ip6->saddr;
4452 ad->u.net->v6info.daddr = ip6->daddr;
4453 ret = 0;
4454
4455 nexthdr = ip6->nexthdr;
4456 offset += sizeof(_ipv6h);
4457 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4458 if (offset < 0)
4459 goto out;
4460
4461 if (proto)
4462 *proto = nexthdr;
4463
4464 switch (nexthdr) {
4465 case IPPROTO_TCP: {
4466 struct tcphdr _tcph, *th;
4467
4468 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4469 if (th == NULL)
4470 break;
4471
4472 ad->u.net->sport = th->source;
4473 ad->u.net->dport = th->dest;
4474 break;
4475 }
4476
4477 case IPPROTO_UDP: {
4478 struct udphdr _udph, *uh;
4479
4480 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4481 if (uh == NULL)
4482 break;
4483
4484 ad->u.net->sport = uh->source;
4485 ad->u.net->dport = uh->dest;
4486 break;
4487 }
4488
4489 case IPPROTO_DCCP: {
4490 struct dccp_hdr _dccph, *dh;
4491
4492 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4493 if (dh == NULL)
4494 break;
4495
4496 ad->u.net->sport = dh->dccph_sport;
4497 ad->u.net->dport = dh->dccph_dport;
4498 break;
4499 }
4500
4501 #if IS_ENABLED(CONFIG_IP_SCTP)
4502 case IPPROTO_SCTP: {
4503 struct sctphdr _sctph, *sh;
4504
4505 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4506 if (sh == NULL)
4507 break;
4508
4509 ad->u.net->sport = sh->source;
4510 ad->u.net->dport = sh->dest;
4511 break;
4512 }
4513 #endif
4514 /* includes fragments */
4515 default:
4516 break;
4517 }
4518 out:
4519 return ret;
4520 }
4521
4522 #endif /* IPV6 */
4523
selinux_parse_skb(struct sk_buff * skb,struct common_audit_data * ad,char ** _addrp,int src,u8 * proto)4524 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4525 char **_addrp, int src, u8 *proto)
4526 {
4527 char *addrp;
4528 int ret;
4529
4530 switch (ad->u.net->family) {
4531 case PF_INET:
4532 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4533 if (ret)
4534 goto parse_error;
4535 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4536 &ad->u.net->v4info.daddr);
4537 goto okay;
4538
4539 #if IS_ENABLED(CONFIG_IPV6)
4540 case PF_INET6:
4541 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4542 if (ret)
4543 goto parse_error;
4544 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4545 &ad->u.net->v6info.daddr);
4546 goto okay;
4547 #endif /* IPV6 */
4548 default:
4549 addrp = NULL;
4550 goto okay;
4551 }
4552
4553 parse_error:
4554 pr_warn(
4555 "SELinux: failure in selinux_parse_skb(),"
4556 " unable to parse packet\n");
4557 return ret;
4558
4559 okay:
4560 if (_addrp)
4561 *_addrp = addrp;
4562 return 0;
4563 }
4564
4565 /**
4566 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4567 * @skb: the packet
4568 * @family: protocol family
4569 * @sid: the packet's peer label SID
4570 *
4571 * Description:
4572 * Check the various different forms of network peer labeling and determine
4573 * the peer label/SID for the packet; most of the magic actually occurs in
4574 * the security server function security_net_peersid_cmp(). The function
4575 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4576 * or -EACCES if @sid is invalid due to inconsistencies with the different
4577 * peer labels.
4578 *
4579 */
selinux_skb_peerlbl_sid(struct sk_buff * skb,u16 family,u32 * sid)4580 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4581 {
4582 int err;
4583 u32 xfrm_sid;
4584 u32 nlbl_sid;
4585 u32 nlbl_type;
4586
4587 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4588 if (unlikely(err))
4589 return -EACCES;
4590 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4591 if (unlikely(err))
4592 return -EACCES;
4593
4594 err = security_net_peersid_resolve(nlbl_sid,
4595 nlbl_type, xfrm_sid, sid);
4596 if (unlikely(err)) {
4597 pr_warn(
4598 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4599 " unable to determine packet's peer label\n");
4600 return -EACCES;
4601 }
4602
4603 return 0;
4604 }
4605
4606 /**
4607 * selinux_conn_sid - Determine the child socket label for a connection
4608 * @sk_sid: the parent socket's SID
4609 * @skb_sid: the packet's SID
4610 * @conn_sid: the resulting connection SID
4611 *
4612 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4613 * combined with the MLS information from @skb_sid in order to create
4614 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy
4615 * of @sk_sid. Returns zero on success, negative values on failure.
4616 *
4617 */
selinux_conn_sid(u32 sk_sid,u32 skb_sid,u32 * conn_sid)4618 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4619 {
4620 int err = 0;
4621
4622 if (skb_sid != SECSID_NULL)
4623 err = security_sid_mls_copy(sk_sid, skb_sid,
4624 conn_sid);
4625 else
4626 *conn_sid = sk_sid;
4627
4628 return err;
4629 }
4630
4631 /* socket security operations */
4632
socket_sockcreate_sid(const struct task_security_struct * tsec,u16 secclass,u32 * socksid)4633 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4634 u16 secclass, u32 *socksid)
4635 {
4636 if (tsec->sockcreate_sid > SECSID_NULL) {
4637 *socksid = tsec->sockcreate_sid;
4638 return 0;
4639 }
4640
4641 return security_transition_sid(tsec->sid, tsec->sid,
4642 secclass, NULL, socksid);
4643 }
4644
sock_skip_has_perm(u32 sid)4645 static bool sock_skip_has_perm(u32 sid)
4646 {
4647 if (sid == SECINITSID_KERNEL)
4648 return true;
4649
4650 /*
4651 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
4652 * inherited the kernel context from early boot used to be skipped
4653 * here, so preserve that behavior unless the capability is set.
4654 *
4655 * By setting the capability the policy signals that it is ready
4656 * for this quirk to be fixed. Note that sockets created by a kernel
4657 * thread or a usermode helper executed without a transition will
4658 * still be skipped in this check regardless of the policycap
4659 * setting.
4660 */
4661 if (!selinux_policycap_userspace_initial_context() &&
4662 sid == SECINITSID_INIT)
4663 return true;
4664 return false;
4665 }
4666
4667
sock_has_perm(struct sock * sk,u32 perms)4668 static int sock_has_perm(struct sock *sk, u32 perms)
4669 {
4670 struct sk_security_struct *sksec = sk->sk_security;
4671 struct common_audit_data ad;
4672 struct lsm_network_audit net;
4673
4674 if (sock_skip_has_perm(sksec->sid))
4675 return 0;
4676
4677 ad_net_init_from_sk(&ad, &net, sk);
4678
4679 return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
4680 &ad);
4681 }
4682
selinux_socket_create(int family,int type,int protocol,int kern)4683 static int selinux_socket_create(int family, int type,
4684 int protocol, int kern)
4685 {
4686 const struct task_security_struct *tsec = selinux_cred(current_cred());
4687 u32 newsid;
4688 u16 secclass;
4689 int rc;
4690
4691 if (kern)
4692 return 0;
4693
4694 secclass = socket_type_to_security_class(family, type, protocol);
4695 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4696 if (rc)
4697 return rc;
4698
4699 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4700 }
4701
selinux_socket_post_create(struct socket * sock,int family,int type,int protocol,int kern)4702 static int selinux_socket_post_create(struct socket *sock, int family,
4703 int type, int protocol, int kern)
4704 {
4705 const struct task_security_struct *tsec = selinux_cred(current_cred());
4706 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4707 struct sk_security_struct *sksec;
4708 u16 sclass = socket_type_to_security_class(family, type, protocol);
4709 u32 sid = SECINITSID_KERNEL;
4710 int err = 0;
4711
4712 if (!kern) {
4713 err = socket_sockcreate_sid(tsec, sclass, &sid);
4714 if (err)
4715 return err;
4716 }
4717
4718 isec->sclass = sclass;
4719 isec->sid = sid;
4720 isec->initialized = LABEL_INITIALIZED;
4721
4722 if (sock->sk) {
4723 sksec = selinux_sock(sock->sk);
4724 sksec->sclass = sclass;
4725 sksec->sid = sid;
4726 /* Allows detection of the first association on this socket */
4727 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4728 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4729
4730 err = selinux_netlbl_socket_post_create(sock->sk, family);
4731 }
4732
4733 return err;
4734 }
4735
selinux_socket_socketpair(struct socket * socka,struct socket * sockb)4736 static int selinux_socket_socketpair(struct socket *socka,
4737 struct socket *sockb)
4738 {
4739 struct sk_security_struct *sksec_a = selinux_sock(socka->sk);
4740 struct sk_security_struct *sksec_b = selinux_sock(sockb->sk);
4741
4742 sksec_a->peer_sid = sksec_b->sid;
4743 sksec_b->peer_sid = sksec_a->sid;
4744
4745 return 0;
4746 }
4747
4748 /* Range of port numbers used to automatically bind.
4749 Need to determine whether we should perform a name_bind
4750 permission check between the socket and the port number. */
4751
selinux_socket_bind(struct socket * sock,struct sockaddr * address,int addrlen)4752 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4753 {
4754 struct sock *sk = sock->sk;
4755 struct sk_security_struct *sksec = selinux_sock(sk);
4756 u16 family;
4757 int err;
4758
4759 err = sock_has_perm(sk, SOCKET__BIND);
4760 if (err)
4761 goto out;
4762
4763 /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4764 family = sk->sk_family;
4765 if (family == PF_INET || family == PF_INET6) {
4766 char *addrp;
4767 struct common_audit_data ad;
4768 struct lsm_network_audit net = {0,};
4769 struct sockaddr_in *addr4 = NULL;
4770 struct sockaddr_in6 *addr6 = NULL;
4771 u16 family_sa;
4772 unsigned short snum;
4773 u32 sid, node_perm;
4774
4775 /*
4776 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4777 * that validates multiple binding addresses. Because of this
4778 * need to check address->sa_family as it is possible to have
4779 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4780 */
4781 if (addrlen < offsetofend(struct sockaddr, sa_family))
4782 return -EINVAL;
4783 family_sa = address->sa_family;
4784 switch (family_sa) {
4785 case AF_UNSPEC:
4786 case AF_INET:
4787 if (addrlen < sizeof(struct sockaddr_in))
4788 return -EINVAL;
4789 addr4 = (struct sockaddr_in *)address;
4790 if (family_sa == AF_UNSPEC) {
4791 if (family == PF_INET6) {
4792 /* Length check from inet6_bind_sk() */
4793 if (addrlen < SIN6_LEN_RFC2133)
4794 return -EINVAL;
4795 /* Family check from __inet6_bind() */
4796 goto err_af;
4797 }
4798 /* see __inet_bind(), we only want to allow
4799 * AF_UNSPEC if the address is INADDR_ANY
4800 */
4801 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4802 goto err_af;
4803 family_sa = AF_INET;
4804 }
4805 snum = ntohs(addr4->sin_port);
4806 addrp = (char *)&addr4->sin_addr.s_addr;
4807 break;
4808 case AF_INET6:
4809 if (addrlen < SIN6_LEN_RFC2133)
4810 return -EINVAL;
4811 addr6 = (struct sockaddr_in6 *)address;
4812 snum = ntohs(addr6->sin6_port);
4813 addrp = (char *)&addr6->sin6_addr.s6_addr;
4814 break;
4815 default:
4816 goto err_af;
4817 }
4818
4819 ad.type = LSM_AUDIT_DATA_NET;
4820 ad.u.net = &net;
4821 ad.u.net->sport = htons(snum);
4822 ad.u.net->family = family_sa;
4823
4824 if (snum) {
4825 int low, high;
4826
4827 inet_get_local_port_range(sock_net(sk), &low, &high);
4828
4829 if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4830 snum < low || snum > high) {
4831 err = sel_netport_sid(sk->sk_protocol,
4832 snum, &sid);
4833 if (err)
4834 goto out;
4835 err = avc_has_perm(sksec->sid, sid,
4836 sksec->sclass,
4837 SOCKET__NAME_BIND, &ad);
4838 if (err)
4839 goto out;
4840 }
4841 }
4842
4843 switch (sksec->sclass) {
4844 case SECCLASS_TCP_SOCKET:
4845 node_perm = TCP_SOCKET__NODE_BIND;
4846 break;
4847
4848 case SECCLASS_UDP_SOCKET:
4849 node_perm = UDP_SOCKET__NODE_BIND;
4850 break;
4851
4852 case SECCLASS_DCCP_SOCKET:
4853 node_perm = DCCP_SOCKET__NODE_BIND;
4854 break;
4855
4856 case SECCLASS_SCTP_SOCKET:
4857 node_perm = SCTP_SOCKET__NODE_BIND;
4858 break;
4859
4860 default:
4861 node_perm = RAWIP_SOCKET__NODE_BIND;
4862 break;
4863 }
4864
4865 err = sel_netnode_sid(addrp, family_sa, &sid);
4866 if (err)
4867 goto out;
4868
4869 if (family_sa == AF_INET)
4870 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4871 else
4872 ad.u.net->v6info.saddr = addr6->sin6_addr;
4873
4874 err = avc_has_perm(sksec->sid, sid,
4875 sksec->sclass, node_perm, &ad);
4876 if (err)
4877 goto out;
4878 }
4879 out:
4880 return err;
4881 err_af:
4882 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4883 if (sk->sk_protocol == IPPROTO_SCTP)
4884 return -EINVAL;
4885 return -EAFNOSUPPORT;
4886 }
4887
4888 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4889 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4890 */
selinux_socket_connect_helper(struct socket * sock,struct sockaddr * address,int addrlen)4891 static int selinux_socket_connect_helper(struct socket *sock,
4892 struct sockaddr *address, int addrlen)
4893 {
4894 struct sock *sk = sock->sk;
4895 struct sk_security_struct *sksec = selinux_sock(sk);
4896 int err;
4897
4898 err = sock_has_perm(sk, SOCKET__CONNECT);
4899 if (err)
4900 return err;
4901 if (addrlen < offsetofend(struct sockaddr, sa_family))
4902 return -EINVAL;
4903
4904 /* connect(AF_UNSPEC) has special handling, as it is a documented
4905 * way to disconnect the socket
4906 */
4907 if (address->sa_family == AF_UNSPEC)
4908 return 0;
4909
4910 /*
4911 * If a TCP, DCCP or SCTP socket, check name_connect permission
4912 * for the port.
4913 */
4914 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4915 sksec->sclass == SECCLASS_DCCP_SOCKET ||
4916 sksec->sclass == SECCLASS_SCTP_SOCKET) {
4917 struct common_audit_data ad;
4918 struct lsm_network_audit net = {0,};
4919 struct sockaddr_in *addr4 = NULL;
4920 struct sockaddr_in6 *addr6 = NULL;
4921 unsigned short snum;
4922 u32 sid, perm;
4923
4924 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4925 * that validates multiple connect addresses. Because of this
4926 * need to check address->sa_family as it is possible to have
4927 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4928 */
4929 switch (address->sa_family) {
4930 case AF_INET:
4931 addr4 = (struct sockaddr_in *)address;
4932 if (addrlen < sizeof(struct sockaddr_in))
4933 return -EINVAL;
4934 snum = ntohs(addr4->sin_port);
4935 break;
4936 case AF_INET6:
4937 addr6 = (struct sockaddr_in6 *)address;
4938 if (addrlen < SIN6_LEN_RFC2133)
4939 return -EINVAL;
4940 snum = ntohs(addr6->sin6_port);
4941 break;
4942 default:
4943 /* Note that SCTP services expect -EINVAL, whereas
4944 * others expect -EAFNOSUPPORT.
4945 */
4946 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4947 return -EINVAL;
4948 else
4949 return -EAFNOSUPPORT;
4950 }
4951
4952 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4953 if (err)
4954 return err;
4955
4956 switch (sksec->sclass) {
4957 case SECCLASS_TCP_SOCKET:
4958 perm = TCP_SOCKET__NAME_CONNECT;
4959 break;
4960 case SECCLASS_DCCP_SOCKET:
4961 perm = DCCP_SOCKET__NAME_CONNECT;
4962 break;
4963 case SECCLASS_SCTP_SOCKET:
4964 perm = SCTP_SOCKET__NAME_CONNECT;
4965 break;
4966 }
4967
4968 ad.type = LSM_AUDIT_DATA_NET;
4969 ad.u.net = &net;
4970 ad.u.net->dport = htons(snum);
4971 ad.u.net->family = address->sa_family;
4972 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4973 if (err)
4974 return err;
4975 }
4976
4977 return 0;
4978 }
4979
4980 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
selinux_socket_connect(struct socket * sock,struct sockaddr * address,int addrlen)4981 static int selinux_socket_connect(struct socket *sock,
4982 struct sockaddr *address, int addrlen)
4983 {
4984 int err;
4985 struct sock *sk = sock->sk;
4986
4987 err = selinux_socket_connect_helper(sock, address, addrlen);
4988 if (err)
4989 return err;
4990
4991 return selinux_netlbl_socket_connect(sk, address);
4992 }
4993
selinux_socket_listen(struct socket * sock,int backlog)4994 static int selinux_socket_listen(struct socket *sock, int backlog)
4995 {
4996 return sock_has_perm(sock->sk, SOCKET__LISTEN);
4997 }
4998
selinux_socket_accept(struct socket * sock,struct socket * newsock)4999 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
5000 {
5001 int err;
5002 struct inode_security_struct *isec;
5003 struct inode_security_struct *newisec;
5004 u16 sclass;
5005 u32 sid;
5006
5007 err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
5008 if (err)
5009 return err;
5010
5011 isec = inode_security_novalidate(SOCK_INODE(sock));
5012 spin_lock(&isec->lock);
5013 sclass = isec->sclass;
5014 sid = isec->sid;
5015 spin_unlock(&isec->lock);
5016
5017 newisec = inode_security_novalidate(SOCK_INODE(newsock));
5018 newisec->sclass = sclass;
5019 newisec->sid = sid;
5020 newisec->initialized = LABEL_INITIALIZED;
5021
5022 return 0;
5023 }
5024
selinux_socket_sendmsg(struct socket * sock,struct msghdr * msg,int size)5025 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
5026 int size)
5027 {
5028 return sock_has_perm(sock->sk, SOCKET__WRITE);
5029 }
5030
selinux_socket_recvmsg(struct socket * sock,struct msghdr * msg,int size,int flags)5031 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
5032 int size, int flags)
5033 {
5034 return sock_has_perm(sock->sk, SOCKET__READ);
5035 }
5036
selinux_socket_getsockname(struct socket * sock)5037 static int selinux_socket_getsockname(struct socket *sock)
5038 {
5039 return sock_has_perm(sock->sk, SOCKET__GETATTR);
5040 }
5041
selinux_socket_getpeername(struct socket * sock)5042 static int selinux_socket_getpeername(struct socket *sock)
5043 {
5044 return sock_has_perm(sock->sk, SOCKET__GETATTR);
5045 }
5046
selinux_socket_setsockopt(struct socket * sock,int level,int optname)5047 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
5048 {
5049 int err;
5050
5051 err = sock_has_perm(sock->sk, SOCKET__SETOPT);
5052 if (err)
5053 return err;
5054
5055 return selinux_netlbl_socket_setsockopt(sock, level, optname);
5056 }
5057
selinux_socket_getsockopt(struct socket * sock,int level,int optname)5058 static int selinux_socket_getsockopt(struct socket *sock, int level,
5059 int optname)
5060 {
5061 return sock_has_perm(sock->sk, SOCKET__GETOPT);
5062 }
5063
selinux_socket_shutdown(struct socket * sock,int how)5064 static int selinux_socket_shutdown(struct socket *sock, int how)
5065 {
5066 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
5067 }
5068
selinux_socket_unix_stream_connect(struct sock * sock,struct sock * other,struct sock * newsk)5069 static int selinux_socket_unix_stream_connect(struct sock *sock,
5070 struct sock *other,
5071 struct sock *newsk)
5072 {
5073 struct sk_security_struct *sksec_sock = selinux_sock(sock);
5074 struct sk_security_struct *sksec_other = selinux_sock(other);
5075 struct sk_security_struct *sksec_new = selinux_sock(newsk);
5076 struct common_audit_data ad;
5077 struct lsm_network_audit net;
5078 int err;
5079
5080 ad_net_init_from_sk(&ad, &net, other);
5081
5082 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
5083 sksec_other->sclass,
5084 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5085 if (err)
5086 return err;
5087
5088 /* server child socket */
5089 sksec_new->peer_sid = sksec_sock->sid;
5090 err = security_sid_mls_copy(sksec_other->sid,
5091 sksec_sock->sid, &sksec_new->sid);
5092 if (err)
5093 return err;
5094
5095 /* connecting socket */
5096 sksec_sock->peer_sid = sksec_new->sid;
5097
5098 return 0;
5099 }
5100
selinux_socket_unix_may_send(struct socket * sock,struct socket * other)5101 static int selinux_socket_unix_may_send(struct socket *sock,
5102 struct socket *other)
5103 {
5104 struct sk_security_struct *ssec = selinux_sock(sock->sk);
5105 struct sk_security_struct *osec = selinux_sock(other->sk);
5106 struct common_audit_data ad;
5107 struct lsm_network_audit net;
5108
5109 ad_net_init_from_sk(&ad, &net, other->sk);
5110
5111 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5112 &ad);
5113 }
5114
selinux_inet_sys_rcv_skb(struct net * ns,int ifindex,char * addrp,u16 family,u32 peer_sid,struct common_audit_data * ad)5115 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5116 char *addrp, u16 family, u32 peer_sid,
5117 struct common_audit_data *ad)
5118 {
5119 int err;
5120 u32 if_sid;
5121 u32 node_sid;
5122
5123 err = sel_netif_sid(ns, ifindex, &if_sid);
5124 if (err)
5125 return err;
5126 err = avc_has_perm(peer_sid, if_sid,
5127 SECCLASS_NETIF, NETIF__INGRESS, ad);
5128 if (err)
5129 return err;
5130
5131 err = sel_netnode_sid(addrp, family, &node_sid);
5132 if (err)
5133 return err;
5134 return avc_has_perm(peer_sid, node_sid,
5135 SECCLASS_NODE, NODE__RECVFROM, ad);
5136 }
5137
selinux_sock_rcv_skb_compat(struct sock * sk,struct sk_buff * skb,u16 family)5138 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5139 u16 family)
5140 {
5141 int err = 0;
5142 struct sk_security_struct *sksec = selinux_sock(sk);
5143 u32 sk_sid = sksec->sid;
5144 struct common_audit_data ad;
5145 struct lsm_network_audit net;
5146 char *addrp;
5147
5148 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5149 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5150 if (err)
5151 return err;
5152
5153 if (selinux_secmark_enabled()) {
5154 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5155 PACKET__RECV, &ad);
5156 if (err)
5157 return err;
5158 }
5159
5160 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5161 if (err)
5162 return err;
5163 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5164
5165 return err;
5166 }
5167
selinux_socket_sock_rcv_skb(struct sock * sk,struct sk_buff * skb)5168 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5169 {
5170 int err, peerlbl_active, secmark_active;
5171 struct sk_security_struct *sksec = selinux_sock(sk);
5172 u16 family = sk->sk_family;
5173 u32 sk_sid = sksec->sid;
5174 struct common_audit_data ad;
5175 struct lsm_network_audit net;
5176 char *addrp;
5177
5178 if (family != PF_INET && family != PF_INET6)
5179 return 0;
5180
5181 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5182 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5183 family = PF_INET;
5184
5185 /* If any sort of compatibility mode is enabled then handoff processing
5186 * to the selinux_sock_rcv_skb_compat() function to deal with the
5187 * special handling. We do this in an attempt to keep this function
5188 * as fast and as clean as possible. */
5189 if (!selinux_policycap_netpeer())
5190 return selinux_sock_rcv_skb_compat(sk, skb, family);
5191
5192 secmark_active = selinux_secmark_enabled();
5193 peerlbl_active = selinux_peerlbl_enabled();
5194 if (!secmark_active && !peerlbl_active)
5195 return 0;
5196
5197 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5198 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5199 if (err)
5200 return err;
5201
5202 if (peerlbl_active) {
5203 u32 peer_sid;
5204
5205 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5206 if (err)
5207 return err;
5208 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5209 addrp, family, peer_sid, &ad);
5210 if (err) {
5211 selinux_netlbl_err(skb, family, err, 0);
5212 return err;
5213 }
5214 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
5215 PEER__RECV, &ad);
5216 if (err) {
5217 selinux_netlbl_err(skb, family, err, 0);
5218 return err;
5219 }
5220 }
5221
5222 if (secmark_active) {
5223 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5224 PACKET__RECV, &ad);
5225 if (err)
5226 return err;
5227 }
5228
5229 return err;
5230 }
5231
selinux_socket_getpeersec_stream(struct socket * sock,sockptr_t optval,sockptr_t optlen,unsigned int len)5232 static int selinux_socket_getpeersec_stream(struct socket *sock,
5233 sockptr_t optval, sockptr_t optlen,
5234 unsigned int len)
5235 {
5236 int err = 0;
5237 char *scontext = NULL;
5238 u32 scontext_len;
5239 struct sk_security_struct *sksec = selinux_sock(sock->sk);
5240 u32 peer_sid = SECSID_NULL;
5241
5242 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5243 sksec->sclass == SECCLASS_TCP_SOCKET ||
5244 sksec->sclass == SECCLASS_SCTP_SOCKET)
5245 peer_sid = sksec->peer_sid;
5246 if (peer_sid == SECSID_NULL)
5247 return -ENOPROTOOPT;
5248
5249 err = security_sid_to_context(peer_sid, &scontext,
5250 &scontext_len);
5251 if (err)
5252 return err;
5253 if (scontext_len > len) {
5254 err = -ERANGE;
5255 goto out_len;
5256 }
5257
5258 if (copy_to_sockptr(optval, scontext, scontext_len))
5259 err = -EFAULT;
5260 out_len:
5261 if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5262 err = -EFAULT;
5263 kfree(scontext);
5264 return err;
5265 }
5266
selinux_socket_getpeersec_dgram(struct socket * sock,struct sk_buff * skb,u32 * secid)5267 static int selinux_socket_getpeersec_dgram(struct socket *sock,
5268 struct sk_buff *skb, u32 *secid)
5269 {
5270 u32 peer_secid = SECSID_NULL;
5271 u16 family;
5272
5273 if (skb && skb->protocol == htons(ETH_P_IP))
5274 family = PF_INET;
5275 else if (skb && skb->protocol == htons(ETH_P_IPV6))
5276 family = PF_INET6;
5277 else if (sock)
5278 family = sock->sk->sk_family;
5279 else {
5280 *secid = SECSID_NULL;
5281 return -EINVAL;
5282 }
5283
5284 if (sock && family == PF_UNIX) {
5285 struct inode_security_struct *isec;
5286 isec = inode_security_novalidate(SOCK_INODE(sock));
5287 peer_secid = isec->sid;
5288 } else if (skb)
5289 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5290
5291 *secid = peer_secid;
5292 if (peer_secid == SECSID_NULL)
5293 return -ENOPROTOOPT;
5294 return 0;
5295 }
5296
selinux_sk_alloc_security(struct sock * sk,int family,gfp_t priority)5297 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5298 {
5299 struct sk_security_struct *sksec = selinux_sock(sk);
5300
5301 sksec->peer_sid = SECINITSID_UNLABELED;
5302 sksec->sid = SECINITSID_UNLABELED;
5303 sksec->sclass = SECCLASS_SOCKET;
5304 selinux_netlbl_sk_security_reset(sksec);
5305
5306 return 0;
5307 }
5308
selinux_sk_free_security(struct sock * sk)5309 static void selinux_sk_free_security(struct sock *sk)
5310 {
5311 struct sk_security_struct *sksec = selinux_sock(sk);
5312
5313 selinux_netlbl_sk_security_free(sksec);
5314 }
5315
selinux_sk_clone_security(const struct sock * sk,struct sock * newsk)5316 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5317 {
5318 struct sk_security_struct *sksec = selinux_sock(sk);
5319 struct sk_security_struct *newsksec = selinux_sock(newsk);
5320
5321 newsksec->sid = sksec->sid;
5322 newsksec->peer_sid = sksec->peer_sid;
5323 newsksec->sclass = sksec->sclass;
5324
5325 selinux_netlbl_sk_security_reset(newsksec);
5326 }
5327
selinux_sk_getsecid(const struct sock * sk,u32 * secid)5328 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid)
5329 {
5330 if (!sk)
5331 *secid = SECINITSID_ANY_SOCKET;
5332 else {
5333 const struct sk_security_struct *sksec = selinux_sock(sk);
5334
5335 *secid = sksec->sid;
5336 }
5337 }
5338
selinux_sock_graft(struct sock * sk,struct socket * parent)5339 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5340 {
5341 struct inode_security_struct *isec =
5342 inode_security_novalidate(SOCK_INODE(parent));
5343 struct sk_security_struct *sksec = selinux_sock(sk);
5344
5345 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5346 sk->sk_family == PF_UNIX)
5347 isec->sid = sksec->sid;
5348 sksec->sclass = isec->sclass;
5349 }
5350
5351 /*
5352 * Determines peer_secid for the asoc and updates socket's peer label
5353 * if it's the first association on the socket.
5354 */
selinux_sctp_process_new_assoc(struct sctp_association * asoc,struct sk_buff * skb)5355 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5356 struct sk_buff *skb)
5357 {
5358 struct sock *sk = asoc->base.sk;
5359 u16 family = sk->sk_family;
5360 struct sk_security_struct *sksec = selinux_sock(sk);
5361 struct common_audit_data ad;
5362 struct lsm_network_audit net;
5363 int err;
5364
5365 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5366 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5367 family = PF_INET;
5368
5369 if (selinux_peerlbl_enabled()) {
5370 asoc->peer_secid = SECSID_NULL;
5371
5372 /* This will return peer_sid = SECSID_NULL if there are
5373 * no peer labels, see security_net_peersid_resolve().
5374 */
5375 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5376 if (err)
5377 return err;
5378
5379 if (asoc->peer_secid == SECSID_NULL)
5380 asoc->peer_secid = SECINITSID_UNLABELED;
5381 } else {
5382 asoc->peer_secid = SECINITSID_UNLABELED;
5383 }
5384
5385 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5386 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5387
5388 /* Here as first association on socket. As the peer SID
5389 * was allowed by peer recv (and the netif/node checks),
5390 * then it is approved by policy and used as the primary
5391 * peer SID for getpeercon(3).
5392 */
5393 sksec->peer_sid = asoc->peer_secid;
5394 } else if (sksec->peer_sid != asoc->peer_secid) {
5395 /* Other association peer SIDs are checked to enforce
5396 * consistency among the peer SIDs.
5397 */
5398 ad_net_init_from_sk(&ad, &net, asoc->base.sk);
5399 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5400 sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5401 &ad);
5402 if (err)
5403 return err;
5404 }
5405 return 0;
5406 }
5407
5408 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5409 * happens on an incoming connect(2), sctp_connectx(3) or
5410 * sctp_sendmsg(3) (with no association already present).
5411 */
selinux_sctp_assoc_request(struct sctp_association * asoc,struct sk_buff * skb)5412 static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5413 struct sk_buff *skb)
5414 {
5415 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5416 u32 conn_sid;
5417 int err;
5418
5419 if (!selinux_policycap_extsockclass())
5420 return 0;
5421
5422 err = selinux_sctp_process_new_assoc(asoc, skb);
5423 if (err)
5424 return err;
5425
5426 /* Compute the MLS component for the connection and store
5427 * the information in asoc. This will be used by SCTP TCP type
5428 * sockets and peeled off connections as they cause a new
5429 * socket to be generated. selinux_sctp_sk_clone() will then
5430 * plug this into the new socket.
5431 */
5432 err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5433 if (err)
5434 return err;
5435
5436 asoc->secid = conn_sid;
5437
5438 /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5439 return selinux_netlbl_sctp_assoc_request(asoc, skb);
5440 }
5441
5442 /* Called when SCTP receives a COOKIE ACK chunk as the final
5443 * response to an association request (initited by us).
5444 */
selinux_sctp_assoc_established(struct sctp_association * asoc,struct sk_buff * skb)5445 static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5446 struct sk_buff *skb)
5447 {
5448 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5449
5450 if (!selinux_policycap_extsockclass())
5451 return 0;
5452
5453 /* Inherit secid from the parent socket - this will be picked up
5454 * by selinux_sctp_sk_clone() if the association gets peeled off
5455 * into a new socket.
5456 */
5457 asoc->secid = sksec->sid;
5458
5459 return selinux_sctp_process_new_assoc(asoc, skb);
5460 }
5461
5462 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5463 * based on their @optname.
5464 */
selinux_sctp_bind_connect(struct sock * sk,int optname,struct sockaddr * address,int addrlen)5465 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5466 struct sockaddr *address,
5467 int addrlen)
5468 {
5469 int len, err = 0, walk_size = 0;
5470 void *addr_buf;
5471 struct sockaddr *addr;
5472 struct socket *sock;
5473
5474 if (!selinux_policycap_extsockclass())
5475 return 0;
5476
5477 /* Process one or more addresses that may be IPv4 or IPv6 */
5478 sock = sk->sk_socket;
5479 addr_buf = address;
5480
5481 while (walk_size < addrlen) {
5482 if (walk_size + sizeof(sa_family_t) > addrlen)
5483 return -EINVAL;
5484
5485 addr = addr_buf;
5486 switch (addr->sa_family) {
5487 case AF_UNSPEC:
5488 case AF_INET:
5489 len = sizeof(struct sockaddr_in);
5490 break;
5491 case AF_INET6:
5492 len = sizeof(struct sockaddr_in6);
5493 break;
5494 default:
5495 return -EINVAL;
5496 }
5497
5498 if (walk_size + len > addrlen)
5499 return -EINVAL;
5500
5501 err = -EINVAL;
5502 switch (optname) {
5503 /* Bind checks */
5504 case SCTP_PRIMARY_ADDR:
5505 case SCTP_SET_PEER_PRIMARY_ADDR:
5506 case SCTP_SOCKOPT_BINDX_ADD:
5507 err = selinux_socket_bind(sock, addr, len);
5508 break;
5509 /* Connect checks */
5510 case SCTP_SOCKOPT_CONNECTX:
5511 case SCTP_PARAM_SET_PRIMARY:
5512 case SCTP_PARAM_ADD_IP:
5513 case SCTP_SENDMSG_CONNECT:
5514 err = selinux_socket_connect_helper(sock, addr, len);
5515 if (err)
5516 return err;
5517
5518 /* As selinux_sctp_bind_connect() is called by the
5519 * SCTP protocol layer, the socket is already locked,
5520 * therefore selinux_netlbl_socket_connect_locked()
5521 * is called here. The situations handled are:
5522 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5523 * whenever a new IP address is added or when a new
5524 * primary address is selected.
5525 * Note that an SCTP connect(2) call happens before
5526 * the SCTP protocol layer and is handled via
5527 * selinux_socket_connect().
5528 */
5529 err = selinux_netlbl_socket_connect_locked(sk, addr);
5530 break;
5531 }
5532
5533 if (err)
5534 return err;
5535
5536 addr_buf += len;
5537 walk_size += len;
5538 }
5539
5540 return 0;
5541 }
5542
5543 /* 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)5544 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5545 struct sock *newsk)
5546 {
5547 struct sk_security_struct *sksec = selinux_sock(sk);
5548 struct sk_security_struct *newsksec = selinux_sock(newsk);
5549
5550 /* If policy does not support SECCLASS_SCTP_SOCKET then call
5551 * the non-sctp clone version.
5552 */
5553 if (!selinux_policycap_extsockclass())
5554 return selinux_sk_clone_security(sk, newsk);
5555
5556 newsksec->sid = asoc->secid;
5557 newsksec->peer_sid = asoc->peer_secid;
5558 newsksec->sclass = sksec->sclass;
5559 selinux_netlbl_sctp_sk_clone(sk, newsk);
5560 }
5561
selinux_mptcp_add_subflow(struct sock * sk,struct sock * ssk)5562 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5563 {
5564 struct sk_security_struct *ssksec = selinux_sock(ssk);
5565 struct sk_security_struct *sksec = selinux_sock(sk);
5566
5567 ssksec->sclass = sksec->sclass;
5568 ssksec->sid = sksec->sid;
5569
5570 /* replace the existing subflow label deleting the existing one
5571 * and re-recreating a new label using the updated context
5572 */
5573 selinux_netlbl_sk_security_free(ssksec);
5574 return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5575 }
5576
selinux_inet_conn_request(const struct sock * sk,struct sk_buff * skb,struct request_sock * req)5577 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5578 struct request_sock *req)
5579 {
5580 struct sk_security_struct *sksec = selinux_sock(sk);
5581 int err;
5582 u16 family = req->rsk_ops->family;
5583 u32 connsid;
5584 u32 peersid;
5585
5586 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5587 if (err)
5588 return err;
5589 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5590 if (err)
5591 return err;
5592 req->secid = connsid;
5593 req->peer_secid = peersid;
5594
5595 return selinux_netlbl_inet_conn_request(req, family);
5596 }
5597
selinux_inet_csk_clone(struct sock * newsk,const struct request_sock * req)5598 static void selinux_inet_csk_clone(struct sock *newsk,
5599 const struct request_sock *req)
5600 {
5601 struct sk_security_struct *newsksec = selinux_sock(newsk);
5602
5603 newsksec->sid = req->secid;
5604 newsksec->peer_sid = req->peer_secid;
5605 /* NOTE: Ideally, we should also get the isec->sid for the
5606 new socket in sync, but we don't have the isec available yet.
5607 So we will wait until sock_graft to do it, by which
5608 time it will have been created and available. */
5609
5610 /* We don't need to take any sort of lock here as we are the only
5611 * thread with access to newsksec */
5612 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5613 }
5614
selinux_inet_conn_established(struct sock * sk,struct sk_buff * skb)5615 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5616 {
5617 u16 family = sk->sk_family;
5618 struct sk_security_struct *sksec = selinux_sock(sk);
5619
5620 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5621 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5622 family = PF_INET;
5623
5624 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5625 }
5626
selinux_secmark_relabel_packet(u32 sid)5627 static int selinux_secmark_relabel_packet(u32 sid)
5628 {
5629 return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO,
5630 NULL);
5631 }
5632
selinux_secmark_refcount_inc(void)5633 static void selinux_secmark_refcount_inc(void)
5634 {
5635 atomic_inc(&selinux_secmark_refcount);
5636 }
5637
selinux_secmark_refcount_dec(void)5638 static void selinux_secmark_refcount_dec(void)
5639 {
5640 atomic_dec(&selinux_secmark_refcount);
5641 }
5642
selinux_req_classify_flow(const struct request_sock * req,struct flowi_common * flic)5643 static void selinux_req_classify_flow(const struct request_sock *req,
5644 struct flowi_common *flic)
5645 {
5646 flic->flowic_secid = req->secid;
5647 }
5648
selinux_tun_dev_alloc_security(void * security)5649 static int selinux_tun_dev_alloc_security(void *security)
5650 {
5651 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5652
5653 tunsec->sid = current_sid();
5654 return 0;
5655 }
5656
selinux_tun_dev_create(void)5657 static int selinux_tun_dev_create(void)
5658 {
5659 u32 sid = current_sid();
5660
5661 /* we aren't taking into account the "sockcreate" SID since the socket
5662 * that is being created here is not a socket in the traditional sense,
5663 * instead it is a private sock, accessible only to the kernel, and
5664 * representing a wide range of network traffic spanning multiple
5665 * connections unlike traditional sockets - check the TUN driver to
5666 * get a better understanding of why this socket is special */
5667
5668 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5669 NULL);
5670 }
5671
selinux_tun_dev_attach_queue(void * security)5672 static int selinux_tun_dev_attach_queue(void *security)
5673 {
5674 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5675
5676 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5677 TUN_SOCKET__ATTACH_QUEUE, NULL);
5678 }
5679
selinux_tun_dev_attach(struct sock * sk,void * security)5680 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5681 {
5682 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5683 struct sk_security_struct *sksec = selinux_sock(sk);
5684
5685 /* we don't currently perform any NetLabel based labeling here and it
5686 * isn't clear that we would want to do so anyway; while we could apply
5687 * labeling without the support of the TUN user the resulting labeled
5688 * traffic from the other end of the connection would almost certainly
5689 * cause confusion to the TUN user that had no idea network labeling
5690 * protocols were being used */
5691
5692 sksec->sid = tunsec->sid;
5693 sksec->sclass = SECCLASS_TUN_SOCKET;
5694
5695 return 0;
5696 }
5697
selinux_tun_dev_open(void * security)5698 static int selinux_tun_dev_open(void *security)
5699 {
5700 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5701 u32 sid = current_sid();
5702 int err;
5703
5704 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5705 TUN_SOCKET__RELABELFROM, NULL);
5706 if (err)
5707 return err;
5708 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5709 TUN_SOCKET__RELABELTO, NULL);
5710 if (err)
5711 return err;
5712 tunsec->sid = sid;
5713
5714 return 0;
5715 }
5716
5717 #ifdef CONFIG_NETFILTER
5718
selinux_ip_forward(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)5719 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5720 const struct nf_hook_state *state)
5721 {
5722 int ifindex;
5723 u16 family;
5724 char *addrp;
5725 u32 peer_sid;
5726 struct common_audit_data ad;
5727 struct lsm_network_audit net;
5728 int secmark_active, peerlbl_active;
5729
5730 if (!selinux_policycap_netpeer())
5731 return NF_ACCEPT;
5732
5733 secmark_active = selinux_secmark_enabled();
5734 peerlbl_active = selinux_peerlbl_enabled();
5735 if (!secmark_active && !peerlbl_active)
5736 return NF_ACCEPT;
5737
5738 family = state->pf;
5739 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5740 return NF_DROP;
5741
5742 ifindex = state->in->ifindex;
5743 ad_net_init_from_iif(&ad, &net, ifindex, family);
5744 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5745 return NF_DROP;
5746
5747 if (peerlbl_active) {
5748 int err;
5749
5750 err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5751 addrp, family, peer_sid, &ad);
5752 if (err) {
5753 selinux_netlbl_err(skb, family, err, 1);
5754 return NF_DROP;
5755 }
5756 }
5757
5758 if (secmark_active)
5759 if (avc_has_perm(peer_sid, skb->secmark,
5760 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5761 return NF_DROP;
5762
5763 if (netlbl_enabled())
5764 /* we do this in the FORWARD path and not the POST_ROUTING
5765 * path because we want to make sure we apply the necessary
5766 * labeling before IPsec is applied so we can leverage AH
5767 * protection */
5768 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5769 return NF_DROP;
5770
5771 return NF_ACCEPT;
5772 }
5773
selinux_ip_output(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)5774 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5775 const struct nf_hook_state *state)
5776 {
5777 struct sock *sk;
5778 u32 sid;
5779
5780 if (!netlbl_enabled())
5781 return NF_ACCEPT;
5782
5783 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5784 * because we want to make sure we apply the necessary labeling
5785 * before IPsec is applied so we can leverage AH protection */
5786 sk = sk_to_full_sk(skb->sk);
5787 if (sk) {
5788 struct sk_security_struct *sksec;
5789
5790 if (sk_listener(sk))
5791 /* if the socket is the listening state then this
5792 * packet is a SYN-ACK packet which means it needs to
5793 * be labeled based on the connection/request_sock and
5794 * not the parent socket. unfortunately, we can't
5795 * lookup the request_sock yet as it isn't queued on
5796 * the parent socket until after the SYN-ACK is sent.
5797 * the "solution" is to simply pass the packet as-is
5798 * as any IP option based labeling should be copied
5799 * from the initial connection request (in the IP
5800 * layer). it is far from ideal, but until we get a
5801 * security label in the packet itself this is the
5802 * best we can do. */
5803 return NF_ACCEPT;
5804
5805 /* standard practice, label using the parent socket */
5806 sksec = selinux_sock(sk);
5807 sid = sksec->sid;
5808 } else
5809 sid = SECINITSID_KERNEL;
5810 if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5811 return NF_DROP;
5812
5813 return NF_ACCEPT;
5814 }
5815
5816
selinux_ip_postroute_compat(struct sk_buff * skb,const struct nf_hook_state * state)5817 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5818 const struct nf_hook_state *state)
5819 {
5820 struct sock *sk;
5821 struct sk_security_struct *sksec;
5822 struct common_audit_data ad;
5823 struct lsm_network_audit net;
5824 u8 proto = 0;
5825
5826 sk = skb_to_full_sk(skb);
5827 if (sk == NULL)
5828 return NF_ACCEPT;
5829 sksec = selinux_sock(sk);
5830
5831 ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf);
5832 if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5833 return NF_DROP;
5834
5835 if (selinux_secmark_enabled())
5836 if (avc_has_perm(sksec->sid, skb->secmark,
5837 SECCLASS_PACKET, PACKET__SEND, &ad))
5838 return NF_DROP_ERR(-ECONNREFUSED);
5839
5840 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5841 return NF_DROP_ERR(-ECONNREFUSED);
5842
5843 return NF_ACCEPT;
5844 }
5845
selinux_ip_postroute(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)5846 static unsigned int selinux_ip_postroute(void *priv,
5847 struct sk_buff *skb,
5848 const struct nf_hook_state *state)
5849 {
5850 u16 family;
5851 u32 secmark_perm;
5852 u32 peer_sid;
5853 int ifindex;
5854 struct sock *sk;
5855 struct common_audit_data ad;
5856 struct lsm_network_audit net;
5857 char *addrp;
5858 int secmark_active, peerlbl_active;
5859
5860 /* If any sort of compatibility mode is enabled then handoff processing
5861 * to the selinux_ip_postroute_compat() function to deal with the
5862 * special handling. We do this in an attempt to keep this function
5863 * as fast and as clean as possible. */
5864 if (!selinux_policycap_netpeer())
5865 return selinux_ip_postroute_compat(skb, state);
5866
5867 secmark_active = selinux_secmark_enabled();
5868 peerlbl_active = selinux_peerlbl_enabled();
5869 if (!secmark_active && !peerlbl_active)
5870 return NF_ACCEPT;
5871
5872 sk = skb_to_full_sk(skb);
5873
5874 #ifdef CONFIG_XFRM
5875 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5876 * packet transformation so allow the packet to pass without any checks
5877 * since we'll have another chance to perform access control checks
5878 * when the packet is on it's final way out.
5879 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5880 * is NULL, in this case go ahead and apply access control.
5881 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5882 * TCP listening state we cannot wait until the XFRM processing
5883 * is done as we will miss out on the SA label if we do;
5884 * unfortunately, this means more work, but it is only once per
5885 * connection. */
5886 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5887 !(sk && sk_listener(sk)))
5888 return NF_ACCEPT;
5889 #endif
5890
5891 family = state->pf;
5892 if (sk == NULL) {
5893 /* Without an associated socket the packet is either coming
5894 * from the kernel or it is being forwarded; check the packet
5895 * to determine which and if the packet is being forwarded
5896 * query the packet directly to determine the security label. */
5897 if (skb->skb_iif) {
5898 secmark_perm = PACKET__FORWARD_OUT;
5899 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5900 return NF_DROP;
5901 } else {
5902 secmark_perm = PACKET__SEND;
5903 peer_sid = SECINITSID_KERNEL;
5904 }
5905 } else if (sk_listener(sk)) {
5906 /* Locally generated packet but the associated socket is in the
5907 * listening state which means this is a SYN-ACK packet. In
5908 * this particular case the correct security label is assigned
5909 * to the connection/request_sock but unfortunately we can't
5910 * query the request_sock as it isn't queued on the parent
5911 * socket until after the SYN-ACK packet is sent; the only
5912 * viable choice is to regenerate the label like we do in
5913 * selinux_inet_conn_request(). See also selinux_ip_output()
5914 * for similar problems. */
5915 u32 skb_sid;
5916 struct sk_security_struct *sksec;
5917
5918 sksec = selinux_sock(sk);
5919 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5920 return NF_DROP;
5921 /* At this point, if the returned skb peerlbl is SECSID_NULL
5922 * and the packet has been through at least one XFRM
5923 * transformation then we must be dealing with the "final"
5924 * form of labeled IPsec packet; since we've already applied
5925 * all of our access controls on this packet we can safely
5926 * pass the packet. */
5927 if (skb_sid == SECSID_NULL) {
5928 switch (family) {
5929 case PF_INET:
5930 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5931 return NF_ACCEPT;
5932 break;
5933 case PF_INET6:
5934 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5935 return NF_ACCEPT;
5936 break;
5937 default:
5938 return NF_DROP_ERR(-ECONNREFUSED);
5939 }
5940 }
5941 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5942 return NF_DROP;
5943 secmark_perm = PACKET__SEND;
5944 } else {
5945 /* Locally generated packet, fetch the security label from the
5946 * associated socket. */
5947 struct sk_security_struct *sksec = selinux_sock(sk);
5948 peer_sid = sksec->sid;
5949 secmark_perm = PACKET__SEND;
5950 }
5951
5952 ifindex = state->out->ifindex;
5953 ad_net_init_from_iif(&ad, &net, ifindex, family);
5954 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5955 return NF_DROP;
5956
5957 if (secmark_active)
5958 if (avc_has_perm(peer_sid, skb->secmark,
5959 SECCLASS_PACKET, secmark_perm, &ad))
5960 return NF_DROP_ERR(-ECONNREFUSED);
5961
5962 if (peerlbl_active) {
5963 u32 if_sid;
5964 u32 node_sid;
5965
5966 if (sel_netif_sid(state->net, ifindex, &if_sid))
5967 return NF_DROP;
5968 if (avc_has_perm(peer_sid, if_sid,
5969 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5970 return NF_DROP_ERR(-ECONNREFUSED);
5971
5972 if (sel_netnode_sid(addrp, family, &node_sid))
5973 return NF_DROP;
5974 if (avc_has_perm(peer_sid, node_sid,
5975 SECCLASS_NODE, NODE__SENDTO, &ad))
5976 return NF_DROP_ERR(-ECONNREFUSED);
5977 }
5978
5979 return NF_ACCEPT;
5980 }
5981 #endif /* CONFIG_NETFILTER */
5982
nlmsg_sock_has_extended_perms(struct sock * sk,u32 perms,u16 nlmsg_type)5983 static int nlmsg_sock_has_extended_perms(struct sock *sk, u32 perms, u16 nlmsg_type)
5984 {
5985 struct sk_security_struct *sksec = sk->sk_security;
5986 struct common_audit_data ad;
5987 u8 driver;
5988 u8 xperm;
5989
5990 if (sock_skip_has_perm(sksec->sid))
5991 return 0;
5992
5993 ad.type = LSM_AUDIT_DATA_NLMSGTYPE;
5994 ad.u.nlmsg_type = nlmsg_type;
5995
5996 driver = nlmsg_type >> 8;
5997 xperm = nlmsg_type & 0xff;
5998
5999 return avc_has_extended_perms(current_sid(), sksec->sid, sksec->sclass,
6000 perms, driver, AVC_EXT_NLMSG, xperm, &ad);
6001 }
6002
selinux_netlink_send(struct sock * sk,struct sk_buff * skb)6003 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
6004 {
6005 int rc = 0;
6006 unsigned int msg_len;
6007 unsigned int data_len = skb->len;
6008 unsigned char *data = skb->data;
6009 struct nlmsghdr *nlh;
6010 struct sk_security_struct *sksec = selinux_sock(sk);
6011 u16 sclass = sksec->sclass;
6012 u32 perm;
6013
6014 while (data_len >= nlmsg_total_size(0)) {
6015 nlh = (struct nlmsghdr *)data;
6016
6017 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
6018 * users which means we can't reject skb's with bogus
6019 * length fields; our solution is to follow what
6020 * netlink_rcv_skb() does and simply skip processing at
6021 * messages with length fields that are clearly junk
6022 */
6023 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
6024 return 0;
6025
6026 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
6027 if (rc == 0) {
6028 if (selinux_policycap_netlink_xperm()) {
6029 rc = nlmsg_sock_has_extended_perms(
6030 sk, perm, nlh->nlmsg_type);
6031 } else {
6032 rc = sock_has_perm(sk, perm);
6033 }
6034 if (rc)
6035 return rc;
6036 } else if (rc == -EINVAL) {
6037 /* -EINVAL is a missing msg/perm mapping */
6038 pr_warn_ratelimited("SELinux: unrecognized netlink"
6039 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
6040 " pid=%d comm=%s\n",
6041 sk->sk_protocol, nlh->nlmsg_type,
6042 secclass_map[sclass - 1].name,
6043 task_pid_nr(current), current->comm);
6044 if (enforcing_enabled() &&
6045 !security_get_allow_unknown())
6046 return rc;
6047 rc = 0;
6048 } else if (rc == -ENOENT) {
6049 /* -ENOENT is a missing socket/class mapping, ignore */
6050 rc = 0;
6051 } else {
6052 return rc;
6053 }
6054
6055 /* move to the next message after applying netlink padding */
6056 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
6057 if (msg_len >= data_len)
6058 return 0;
6059 data_len -= msg_len;
6060 data += msg_len;
6061 }
6062
6063 return rc;
6064 }
6065
ipc_init_security(struct ipc_security_struct * isec,u16 sclass)6066 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
6067 {
6068 isec->sclass = sclass;
6069 isec->sid = current_sid();
6070 }
6071
ipc_has_perm(struct kern_ipc_perm * ipc_perms,u32 perms)6072 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
6073 u32 perms)
6074 {
6075 struct ipc_security_struct *isec;
6076 struct common_audit_data ad;
6077 u32 sid = current_sid();
6078
6079 isec = selinux_ipc(ipc_perms);
6080
6081 ad.type = LSM_AUDIT_DATA_IPC;
6082 ad.u.ipc_id = ipc_perms->key;
6083
6084 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
6085 }
6086
selinux_msg_msg_alloc_security(struct msg_msg * msg)6087 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6088 {
6089 struct msg_security_struct *msec;
6090
6091 msec = selinux_msg_msg(msg);
6092 msec->sid = SECINITSID_UNLABELED;
6093
6094 return 0;
6095 }
6096
6097 /* message queue security operations */
selinux_msg_queue_alloc_security(struct kern_ipc_perm * msq)6098 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6099 {
6100 struct ipc_security_struct *isec;
6101 struct common_audit_data ad;
6102 u32 sid = current_sid();
6103
6104 isec = selinux_ipc(msq);
6105 ipc_init_security(isec, SECCLASS_MSGQ);
6106
6107 ad.type = LSM_AUDIT_DATA_IPC;
6108 ad.u.ipc_id = msq->key;
6109
6110 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6111 MSGQ__CREATE, &ad);
6112 }
6113
selinux_msg_queue_associate(struct kern_ipc_perm * msq,int msqflg)6114 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6115 {
6116 struct ipc_security_struct *isec;
6117 struct common_audit_data ad;
6118 u32 sid = current_sid();
6119
6120 isec = selinux_ipc(msq);
6121
6122 ad.type = LSM_AUDIT_DATA_IPC;
6123 ad.u.ipc_id = msq->key;
6124
6125 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6126 MSGQ__ASSOCIATE, &ad);
6127 }
6128
selinux_msg_queue_msgctl(struct kern_ipc_perm * msq,int cmd)6129 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6130 {
6131 u32 perms;
6132
6133 switch (cmd) {
6134 case IPC_INFO:
6135 case MSG_INFO:
6136 /* No specific object, just general system-wide information. */
6137 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6138 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6139 case IPC_STAT:
6140 case MSG_STAT:
6141 case MSG_STAT_ANY:
6142 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6143 break;
6144 case IPC_SET:
6145 perms = MSGQ__SETATTR;
6146 break;
6147 case IPC_RMID:
6148 perms = MSGQ__DESTROY;
6149 break;
6150 default:
6151 return 0;
6152 }
6153
6154 return ipc_has_perm(msq, perms);
6155 }
6156
selinux_msg_queue_msgsnd(struct kern_ipc_perm * msq,struct msg_msg * msg,int msqflg)6157 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6158 {
6159 struct ipc_security_struct *isec;
6160 struct msg_security_struct *msec;
6161 struct common_audit_data ad;
6162 u32 sid = current_sid();
6163 int rc;
6164
6165 isec = selinux_ipc(msq);
6166 msec = selinux_msg_msg(msg);
6167
6168 /*
6169 * First time through, need to assign label to the message
6170 */
6171 if (msec->sid == SECINITSID_UNLABELED) {
6172 /*
6173 * Compute new sid based on current process and
6174 * message queue this message will be stored in
6175 */
6176 rc = security_transition_sid(sid, isec->sid,
6177 SECCLASS_MSG, NULL, &msec->sid);
6178 if (rc)
6179 return rc;
6180 }
6181
6182 ad.type = LSM_AUDIT_DATA_IPC;
6183 ad.u.ipc_id = msq->key;
6184
6185 /* Can this process write to the queue? */
6186 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6187 MSGQ__WRITE, &ad);
6188 if (!rc)
6189 /* Can this process send the message */
6190 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
6191 MSG__SEND, &ad);
6192 if (!rc)
6193 /* Can the message be put in the queue? */
6194 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
6195 MSGQ__ENQUEUE, &ad);
6196
6197 return rc;
6198 }
6199
selinux_msg_queue_msgrcv(struct kern_ipc_perm * msq,struct msg_msg * msg,struct task_struct * target,long type,int mode)6200 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6201 struct task_struct *target,
6202 long type, int mode)
6203 {
6204 struct ipc_security_struct *isec;
6205 struct msg_security_struct *msec;
6206 struct common_audit_data ad;
6207 u32 sid = task_sid_obj(target);
6208 int rc;
6209
6210 isec = selinux_ipc(msq);
6211 msec = selinux_msg_msg(msg);
6212
6213 ad.type = LSM_AUDIT_DATA_IPC;
6214 ad.u.ipc_id = msq->key;
6215
6216 rc = avc_has_perm(sid, isec->sid,
6217 SECCLASS_MSGQ, MSGQ__READ, &ad);
6218 if (!rc)
6219 rc = avc_has_perm(sid, msec->sid,
6220 SECCLASS_MSG, MSG__RECEIVE, &ad);
6221 return rc;
6222 }
6223
6224 /* Shared Memory security operations */
selinux_shm_alloc_security(struct kern_ipc_perm * shp)6225 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6226 {
6227 struct ipc_security_struct *isec;
6228 struct common_audit_data ad;
6229 u32 sid = current_sid();
6230
6231 isec = selinux_ipc(shp);
6232 ipc_init_security(isec, SECCLASS_SHM);
6233
6234 ad.type = LSM_AUDIT_DATA_IPC;
6235 ad.u.ipc_id = shp->key;
6236
6237 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6238 SHM__CREATE, &ad);
6239 }
6240
selinux_shm_associate(struct kern_ipc_perm * shp,int shmflg)6241 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6242 {
6243 struct ipc_security_struct *isec;
6244 struct common_audit_data ad;
6245 u32 sid = current_sid();
6246
6247 isec = selinux_ipc(shp);
6248
6249 ad.type = LSM_AUDIT_DATA_IPC;
6250 ad.u.ipc_id = shp->key;
6251
6252 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6253 SHM__ASSOCIATE, &ad);
6254 }
6255
6256 /* Note, at this point, shp is locked down */
selinux_shm_shmctl(struct kern_ipc_perm * shp,int cmd)6257 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6258 {
6259 u32 perms;
6260
6261 switch (cmd) {
6262 case IPC_INFO:
6263 case SHM_INFO:
6264 /* No specific object, just general system-wide information. */
6265 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6266 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6267 case IPC_STAT:
6268 case SHM_STAT:
6269 case SHM_STAT_ANY:
6270 perms = SHM__GETATTR | SHM__ASSOCIATE;
6271 break;
6272 case IPC_SET:
6273 perms = SHM__SETATTR;
6274 break;
6275 case SHM_LOCK:
6276 case SHM_UNLOCK:
6277 perms = SHM__LOCK;
6278 break;
6279 case IPC_RMID:
6280 perms = SHM__DESTROY;
6281 break;
6282 default:
6283 return 0;
6284 }
6285
6286 return ipc_has_perm(shp, perms);
6287 }
6288
selinux_shm_shmat(struct kern_ipc_perm * shp,char __user * shmaddr,int shmflg)6289 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6290 char __user *shmaddr, int shmflg)
6291 {
6292 u32 perms;
6293
6294 if (shmflg & SHM_RDONLY)
6295 perms = SHM__READ;
6296 else
6297 perms = SHM__READ | SHM__WRITE;
6298
6299 return ipc_has_perm(shp, perms);
6300 }
6301
6302 /* Semaphore security operations */
selinux_sem_alloc_security(struct kern_ipc_perm * sma)6303 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6304 {
6305 struct ipc_security_struct *isec;
6306 struct common_audit_data ad;
6307 u32 sid = current_sid();
6308
6309 isec = selinux_ipc(sma);
6310 ipc_init_security(isec, SECCLASS_SEM);
6311
6312 ad.type = LSM_AUDIT_DATA_IPC;
6313 ad.u.ipc_id = sma->key;
6314
6315 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6316 SEM__CREATE, &ad);
6317 }
6318
selinux_sem_associate(struct kern_ipc_perm * sma,int semflg)6319 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6320 {
6321 struct ipc_security_struct *isec;
6322 struct common_audit_data ad;
6323 u32 sid = current_sid();
6324
6325 isec = selinux_ipc(sma);
6326
6327 ad.type = LSM_AUDIT_DATA_IPC;
6328 ad.u.ipc_id = sma->key;
6329
6330 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6331 SEM__ASSOCIATE, &ad);
6332 }
6333
6334 /* Note, at this point, sma is locked down */
selinux_sem_semctl(struct kern_ipc_perm * sma,int cmd)6335 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6336 {
6337 int err;
6338 u32 perms;
6339
6340 switch (cmd) {
6341 case IPC_INFO:
6342 case SEM_INFO:
6343 /* No specific object, just general system-wide information. */
6344 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6345 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6346 case GETPID:
6347 case GETNCNT:
6348 case GETZCNT:
6349 perms = SEM__GETATTR;
6350 break;
6351 case GETVAL:
6352 case GETALL:
6353 perms = SEM__READ;
6354 break;
6355 case SETVAL:
6356 case SETALL:
6357 perms = SEM__WRITE;
6358 break;
6359 case IPC_RMID:
6360 perms = SEM__DESTROY;
6361 break;
6362 case IPC_SET:
6363 perms = SEM__SETATTR;
6364 break;
6365 case IPC_STAT:
6366 case SEM_STAT:
6367 case SEM_STAT_ANY:
6368 perms = SEM__GETATTR | SEM__ASSOCIATE;
6369 break;
6370 default:
6371 return 0;
6372 }
6373
6374 err = ipc_has_perm(sma, perms);
6375 return err;
6376 }
6377
selinux_sem_semop(struct kern_ipc_perm * sma,struct sembuf * sops,unsigned nsops,int alter)6378 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6379 struct sembuf *sops, unsigned nsops, int alter)
6380 {
6381 u32 perms;
6382
6383 if (alter)
6384 perms = SEM__READ | SEM__WRITE;
6385 else
6386 perms = SEM__READ;
6387
6388 return ipc_has_perm(sma, perms);
6389 }
6390
selinux_ipc_permission(struct kern_ipc_perm * ipcp,short flag)6391 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6392 {
6393 u32 av = 0;
6394
6395 av = 0;
6396 if (flag & S_IRUGO)
6397 av |= IPC__UNIX_READ;
6398 if (flag & S_IWUGO)
6399 av |= IPC__UNIX_WRITE;
6400
6401 if (av == 0)
6402 return 0;
6403
6404 return ipc_has_perm(ipcp, av);
6405 }
6406
selinux_ipc_getlsmprop(struct kern_ipc_perm * ipcp,struct lsm_prop * prop)6407 static void selinux_ipc_getlsmprop(struct kern_ipc_perm *ipcp,
6408 struct lsm_prop *prop)
6409 {
6410 struct ipc_security_struct *isec = selinux_ipc(ipcp);
6411 prop->selinux.secid = isec->sid;
6412 }
6413
selinux_d_instantiate(struct dentry * dentry,struct inode * inode)6414 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6415 {
6416 if (inode)
6417 inode_doinit_with_dentry(inode, dentry);
6418 }
6419
selinux_lsm_getattr(unsigned int attr,struct task_struct * p,char ** value)6420 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
6421 char **value)
6422 {
6423 const struct task_security_struct *tsec;
6424 int error;
6425 u32 sid;
6426 u32 len;
6427
6428 rcu_read_lock();
6429 tsec = selinux_cred(__task_cred(p));
6430 if (p != current) {
6431 error = avc_has_perm(current_sid(), tsec->sid,
6432 SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6433 if (error)
6434 goto err_unlock;
6435 }
6436 switch (attr) {
6437 case LSM_ATTR_CURRENT:
6438 sid = tsec->sid;
6439 break;
6440 case LSM_ATTR_PREV:
6441 sid = tsec->osid;
6442 break;
6443 case LSM_ATTR_EXEC:
6444 sid = tsec->exec_sid;
6445 break;
6446 case LSM_ATTR_FSCREATE:
6447 sid = tsec->create_sid;
6448 break;
6449 case LSM_ATTR_KEYCREATE:
6450 sid = tsec->keycreate_sid;
6451 break;
6452 case LSM_ATTR_SOCKCREATE:
6453 sid = tsec->sockcreate_sid;
6454 break;
6455 default:
6456 error = -EOPNOTSUPP;
6457 goto err_unlock;
6458 }
6459 rcu_read_unlock();
6460
6461 if (sid == SECSID_NULL) {
6462 *value = NULL;
6463 return 0;
6464 }
6465
6466 error = security_sid_to_context(sid, value, &len);
6467 if (error)
6468 return error;
6469 return len;
6470
6471 err_unlock:
6472 rcu_read_unlock();
6473 return error;
6474 }
6475
selinux_lsm_setattr(u64 attr,void * value,size_t size)6476 static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
6477 {
6478 struct task_security_struct *tsec;
6479 struct cred *new;
6480 u32 mysid = current_sid(), sid = 0, ptsid;
6481 int error;
6482 char *str = value;
6483
6484 /*
6485 * Basic control over ability to set these attributes at all.
6486 */
6487 switch (attr) {
6488 case LSM_ATTR_EXEC:
6489 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6490 PROCESS__SETEXEC, NULL);
6491 break;
6492 case LSM_ATTR_FSCREATE:
6493 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6494 PROCESS__SETFSCREATE, NULL);
6495 break;
6496 case LSM_ATTR_KEYCREATE:
6497 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6498 PROCESS__SETKEYCREATE, NULL);
6499 break;
6500 case LSM_ATTR_SOCKCREATE:
6501 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6502 PROCESS__SETSOCKCREATE, NULL);
6503 break;
6504 case LSM_ATTR_CURRENT:
6505 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6506 PROCESS__SETCURRENT, NULL);
6507 break;
6508 default:
6509 error = -EOPNOTSUPP;
6510 break;
6511 }
6512 if (error)
6513 return error;
6514
6515 /* Obtain a SID for the context, if one was specified. */
6516 if (size && str[0] && str[0] != '\n') {
6517 if (str[size-1] == '\n') {
6518 str[size-1] = 0;
6519 size--;
6520 }
6521 error = security_context_to_sid(value, size,
6522 &sid, GFP_KERNEL);
6523 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
6524 if (!has_cap_mac_admin(true)) {
6525 struct audit_buffer *ab;
6526 size_t audit_size;
6527
6528 /* We strip a nul only if it is at the end,
6529 * otherwise the context contains a nul and
6530 * we should audit that */
6531 if (str[size - 1] == '\0')
6532 audit_size = size - 1;
6533 else
6534 audit_size = size;
6535 ab = audit_log_start(audit_context(),
6536 GFP_ATOMIC,
6537 AUDIT_SELINUX_ERR);
6538 if (!ab)
6539 return error;
6540 audit_log_format(ab, "op=fscreate invalid_context=");
6541 audit_log_n_untrustedstring(ab, value,
6542 audit_size);
6543 audit_log_end(ab);
6544
6545 return error;
6546 }
6547 error = security_context_to_sid_force(value, size,
6548 &sid);
6549 }
6550 if (error)
6551 return error;
6552 }
6553
6554 new = prepare_creds();
6555 if (!new)
6556 return -ENOMEM;
6557
6558 /* Permission checking based on the specified context is
6559 performed during the actual operation (execve,
6560 open/mkdir/...), when we know the full context of the
6561 operation. See selinux_bprm_creds_for_exec for the execve
6562 checks and may_create for the file creation checks. The
6563 operation will then fail if the context is not permitted. */
6564 tsec = selinux_cred(new);
6565 if (attr == LSM_ATTR_EXEC) {
6566 tsec->exec_sid = sid;
6567 } else if (attr == LSM_ATTR_FSCREATE) {
6568 tsec->create_sid = sid;
6569 } else if (attr == LSM_ATTR_KEYCREATE) {
6570 if (sid) {
6571 error = avc_has_perm(mysid, sid,
6572 SECCLASS_KEY, KEY__CREATE, NULL);
6573 if (error)
6574 goto abort_change;
6575 }
6576 tsec->keycreate_sid = sid;
6577 } else if (attr == LSM_ATTR_SOCKCREATE) {
6578 tsec->sockcreate_sid = sid;
6579 } else if (attr == LSM_ATTR_CURRENT) {
6580 error = -EINVAL;
6581 if (sid == 0)
6582 goto abort_change;
6583
6584 if (!current_is_single_threaded()) {
6585 error = security_bounded_transition(tsec->sid, sid);
6586 if (error)
6587 goto abort_change;
6588 }
6589
6590 /* Check permissions for the transition. */
6591 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6592 PROCESS__DYNTRANSITION, NULL);
6593 if (error)
6594 goto abort_change;
6595
6596 /* Check for ptracing, and update the task SID if ok.
6597 Otherwise, leave SID unchanged and fail. */
6598 ptsid = ptrace_parent_sid();
6599 if (ptsid != 0) {
6600 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
6601 PROCESS__PTRACE, NULL);
6602 if (error)
6603 goto abort_change;
6604 }
6605
6606 tsec->sid = sid;
6607 } else {
6608 error = -EINVAL;
6609 goto abort_change;
6610 }
6611
6612 commit_creds(new);
6613 return size;
6614
6615 abort_change:
6616 abort_creds(new);
6617 return error;
6618 }
6619
6620 /**
6621 * selinux_getselfattr - Get SELinux current task attributes
6622 * @attr: the requested attribute
6623 * @ctx: buffer to receive the result
6624 * @size: buffer size (input), buffer size used (output)
6625 * @flags: unused
6626 *
6627 * Fill the passed user space @ctx with the details of the requested
6628 * attribute.
6629 *
6630 * Returns the number of attributes on success, an error code otherwise.
6631 * There will only ever be one attribute.
6632 */
selinux_getselfattr(unsigned int attr,struct lsm_ctx __user * ctx,u32 * size,u32 flags)6633 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
6634 u32 *size, u32 flags)
6635 {
6636 int rc;
6637 char *val = NULL;
6638 int val_len;
6639
6640 val_len = selinux_lsm_getattr(attr, current, &val);
6641 if (val_len < 0)
6642 return val_len;
6643 rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0);
6644 kfree(val);
6645 return (!rc ? 1 : rc);
6646 }
6647
selinux_setselfattr(unsigned int attr,struct lsm_ctx * ctx,u32 size,u32 flags)6648 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
6649 u32 size, u32 flags)
6650 {
6651 int rc;
6652
6653 rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len);
6654 if (rc > 0)
6655 return 0;
6656 return rc;
6657 }
6658
selinux_getprocattr(struct task_struct * p,const char * name,char ** value)6659 static int selinux_getprocattr(struct task_struct *p,
6660 const char *name, char **value)
6661 {
6662 unsigned int attr = lsm_name_to_attr(name);
6663 int rc;
6664
6665 if (attr) {
6666 rc = selinux_lsm_getattr(attr, p, value);
6667 if (rc != -EOPNOTSUPP)
6668 return rc;
6669 }
6670
6671 return -EINVAL;
6672 }
6673
selinux_setprocattr(const char * name,void * value,size_t size)6674 static int selinux_setprocattr(const char *name, void *value, size_t size)
6675 {
6676 int attr = lsm_name_to_attr(name);
6677
6678 if (attr)
6679 return selinux_lsm_setattr(attr, value, size);
6680 return -EINVAL;
6681 }
6682
selinux_ismaclabel(const char * name)6683 static int selinux_ismaclabel(const char *name)
6684 {
6685 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6686 }
6687
selinux_secid_to_secctx(u32 secid,struct lsm_context * cp)6688 static int selinux_secid_to_secctx(u32 secid, struct lsm_context *cp)
6689 {
6690 u32 seclen;
6691 int ret;
6692
6693 if (cp) {
6694 cp->id = LSM_ID_SELINUX;
6695 ret = security_sid_to_context(secid, &cp->context, &cp->len);
6696 if (ret < 0)
6697 return ret;
6698 return cp->len;
6699 }
6700 ret = security_sid_to_context(secid, NULL, &seclen);
6701 if (ret < 0)
6702 return ret;
6703 return seclen;
6704 }
6705
selinux_lsmprop_to_secctx(struct lsm_prop * prop,struct lsm_context * cp)6706 static int selinux_lsmprop_to_secctx(struct lsm_prop *prop,
6707 struct lsm_context *cp)
6708 {
6709 return selinux_secid_to_secctx(prop->selinux.secid, cp);
6710 }
6711
selinux_secctx_to_secid(const char * secdata,u32 seclen,u32 * secid)6712 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6713 {
6714 return security_context_to_sid(secdata, seclen,
6715 secid, GFP_KERNEL);
6716 }
6717
selinux_release_secctx(struct lsm_context * cp)6718 static void selinux_release_secctx(struct lsm_context *cp)
6719 {
6720 if (cp->id == LSM_ID_SELINUX) {
6721 kfree(cp->context);
6722 cp->context = NULL;
6723 cp->id = LSM_ID_UNDEF;
6724 }
6725 }
6726
selinux_inode_invalidate_secctx(struct inode * inode)6727 static void selinux_inode_invalidate_secctx(struct inode *inode)
6728 {
6729 struct inode_security_struct *isec = selinux_inode(inode);
6730
6731 spin_lock(&isec->lock);
6732 isec->initialized = LABEL_INVALID;
6733 spin_unlock(&isec->lock);
6734 }
6735
6736 /*
6737 * called with inode->i_mutex locked
6738 */
selinux_inode_notifysecctx(struct inode * inode,void * ctx,u32 ctxlen)6739 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6740 {
6741 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6742 ctx, ctxlen, 0);
6743 /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6744 return rc == -EOPNOTSUPP ? 0 : rc;
6745 }
6746
6747 /*
6748 * called with inode->i_mutex locked
6749 */
selinux_inode_setsecctx(struct dentry * dentry,void * ctx,u32 ctxlen)6750 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6751 {
6752 return __vfs_setxattr_locked(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6753 ctx, ctxlen, 0, NULL);
6754 }
6755
selinux_inode_getsecctx(struct inode * inode,struct lsm_context * cp)6756 static int selinux_inode_getsecctx(struct inode *inode, struct lsm_context *cp)
6757 {
6758 int len;
6759 len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6760 XATTR_SELINUX_SUFFIX,
6761 (void **)&cp->context, true);
6762 if (len < 0)
6763 return len;
6764 cp->len = len;
6765 cp->id = LSM_ID_SELINUX;
6766 return 0;
6767 }
6768 #ifdef CONFIG_KEYS
6769
selinux_key_alloc(struct key * k,const struct cred * cred,unsigned long flags)6770 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6771 unsigned long flags)
6772 {
6773 const struct task_security_struct *tsec;
6774 struct key_security_struct *ksec = selinux_key(k);
6775
6776 tsec = selinux_cred(cred);
6777 if (tsec->keycreate_sid)
6778 ksec->sid = tsec->keycreate_sid;
6779 else
6780 ksec->sid = tsec->sid;
6781
6782 return 0;
6783 }
6784
selinux_key_permission(key_ref_t key_ref,const struct cred * cred,enum key_need_perm need_perm)6785 static int selinux_key_permission(key_ref_t key_ref,
6786 const struct cred *cred,
6787 enum key_need_perm need_perm)
6788 {
6789 struct key *key;
6790 struct key_security_struct *ksec;
6791 u32 perm, sid;
6792
6793 switch (need_perm) {
6794 case KEY_NEED_VIEW:
6795 perm = KEY__VIEW;
6796 break;
6797 case KEY_NEED_READ:
6798 perm = KEY__READ;
6799 break;
6800 case KEY_NEED_WRITE:
6801 perm = KEY__WRITE;
6802 break;
6803 case KEY_NEED_SEARCH:
6804 perm = KEY__SEARCH;
6805 break;
6806 case KEY_NEED_LINK:
6807 perm = KEY__LINK;
6808 break;
6809 case KEY_NEED_SETATTR:
6810 perm = KEY__SETATTR;
6811 break;
6812 case KEY_NEED_UNLINK:
6813 case KEY_SYSADMIN_OVERRIDE:
6814 case KEY_AUTHTOKEN_OVERRIDE:
6815 case KEY_DEFER_PERM_CHECK:
6816 return 0;
6817 default:
6818 WARN_ON(1);
6819 return -EPERM;
6820
6821 }
6822
6823 sid = cred_sid(cred);
6824 key = key_ref_to_ptr(key_ref);
6825 ksec = selinux_key(key);
6826
6827 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6828 }
6829
selinux_key_getsecurity(struct key * key,char ** _buffer)6830 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6831 {
6832 struct key_security_struct *ksec = selinux_key(key);
6833 char *context = NULL;
6834 unsigned len;
6835 int rc;
6836
6837 rc = security_sid_to_context(ksec->sid,
6838 &context, &len);
6839 if (!rc)
6840 rc = len;
6841 *_buffer = context;
6842 return rc;
6843 }
6844
6845 #ifdef CONFIG_KEY_NOTIFICATIONS
selinux_watch_key(struct key * key)6846 static int selinux_watch_key(struct key *key)
6847 {
6848 struct key_security_struct *ksec = selinux_key(key);
6849 u32 sid = current_sid();
6850
6851 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6852 }
6853 #endif
6854 #endif
6855
6856 #ifdef CONFIG_SECURITY_INFINIBAND
selinux_ib_pkey_access(void * ib_sec,u64 subnet_prefix,u16 pkey_val)6857 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6858 {
6859 struct common_audit_data ad;
6860 int err;
6861 u32 sid = 0;
6862 struct ib_security_struct *sec = ib_sec;
6863 struct lsm_ibpkey_audit ibpkey;
6864
6865 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6866 if (err)
6867 return err;
6868
6869 ad.type = LSM_AUDIT_DATA_IBPKEY;
6870 ibpkey.subnet_prefix = subnet_prefix;
6871 ibpkey.pkey = pkey_val;
6872 ad.u.ibpkey = &ibpkey;
6873 return avc_has_perm(sec->sid, sid,
6874 SECCLASS_INFINIBAND_PKEY,
6875 INFINIBAND_PKEY__ACCESS, &ad);
6876 }
6877
selinux_ib_endport_manage_subnet(void * ib_sec,const char * dev_name,u8 port_num)6878 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6879 u8 port_num)
6880 {
6881 struct common_audit_data ad;
6882 int err;
6883 u32 sid = 0;
6884 struct ib_security_struct *sec = ib_sec;
6885 struct lsm_ibendport_audit ibendport;
6886
6887 err = security_ib_endport_sid(dev_name, port_num,
6888 &sid);
6889
6890 if (err)
6891 return err;
6892
6893 ad.type = LSM_AUDIT_DATA_IBENDPORT;
6894 ibendport.dev_name = dev_name;
6895 ibendport.port = port_num;
6896 ad.u.ibendport = &ibendport;
6897 return avc_has_perm(sec->sid, sid,
6898 SECCLASS_INFINIBAND_ENDPORT,
6899 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6900 }
6901
selinux_ib_alloc_security(void * ib_sec)6902 static int selinux_ib_alloc_security(void *ib_sec)
6903 {
6904 struct ib_security_struct *sec = selinux_ib(ib_sec);
6905
6906 sec->sid = current_sid();
6907 return 0;
6908 }
6909 #endif
6910
6911 #ifdef CONFIG_BPF_SYSCALL
selinux_bpf(int cmd,union bpf_attr * attr,unsigned int size,bool kernel)6912 static int selinux_bpf(int cmd, union bpf_attr *attr,
6913 unsigned int size, bool kernel)
6914 {
6915 u32 sid = current_sid();
6916 int ret;
6917
6918 switch (cmd) {
6919 case BPF_MAP_CREATE:
6920 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6921 NULL);
6922 break;
6923 case BPF_PROG_LOAD:
6924 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6925 NULL);
6926 break;
6927 default:
6928 ret = 0;
6929 break;
6930 }
6931
6932 return ret;
6933 }
6934
bpf_map_fmode_to_av(fmode_t fmode)6935 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6936 {
6937 u32 av = 0;
6938
6939 if (fmode & FMODE_READ)
6940 av |= BPF__MAP_READ;
6941 if (fmode & FMODE_WRITE)
6942 av |= BPF__MAP_WRITE;
6943 return av;
6944 }
6945
6946 /* This function will check the file pass through unix socket or binder to see
6947 * if it is a bpf related object. And apply corresponding checks on the bpf
6948 * object based on the type. The bpf maps and programs, not like other files and
6949 * socket, are using a shared anonymous inode inside the kernel as their inode.
6950 * So checking that inode cannot identify if the process have privilege to
6951 * access the bpf object and that's why we have to add this additional check in
6952 * selinux_file_receive and selinux_binder_transfer_files.
6953 */
bpf_fd_pass(const struct file * file,u32 sid)6954 static int bpf_fd_pass(const struct file *file, u32 sid)
6955 {
6956 struct bpf_security_struct *bpfsec;
6957 struct bpf_prog *prog;
6958 struct bpf_map *map;
6959 int ret;
6960
6961 if (file->f_op == &bpf_map_fops) {
6962 map = file->private_data;
6963 bpfsec = map->security;
6964 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6965 bpf_map_fmode_to_av(file->f_mode), NULL);
6966 if (ret)
6967 return ret;
6968 } else if (file->f_op == &bpf_prog_fops) {
6969 prog = file->private_data;
6970 bpfsec = prog->aux->security;
6971 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6972 BPF__PROG_RUN, NULL);
6973 if (ret)
6974 return ret;
6975 }
6976 return 0;
6977 }
6978
selinux_bpf_map(struct bpf_map * map,fmode_t fmode)6979 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6980 {
6981 u32 sid = current_sid();
6982 struct bpf_security_struct *bpfsec;
6983
6984 bpfsec = map->security;
6985 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6986 bpf_map_fmode_to_av(fmode), NULL);
6987 }
6988
selinux_bpf_prog(struct bpf_prog * prog)6989 static int selinux_bpf_prog(struct bpf_prog *prog)
6990 {
6991 u32 sid = current_sid();
6992 struct bpf_security_struct *bpfsec;
6993
6994 bpfsec = prog->aux->security;
6995 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6996 BPF__PROG_RUN, NULL);
6997 }
6998
selinux_bpf_map_create(struct bpf_map * map,union bpf_attr * attr,struct bpf_token * token,bool kernel)6999 static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
7000 struct bpf_token *token, bool kernel)
7001 {
7002 struct bpf_security_struct *bpfsec;
7003
7004 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
7005 if (!bpfsec)
7006 return -ENOMEM;
7007
7008 bpfsec->sid = current_sid();
7009 map->security = bpfsec;
7010
7011 return 0;
7012 }
7013
selinux_bpf_map_free(struct bpf_map * map)7014 static void selinux_bpf_map_free(struct bpf_map *map)
7015 {
7016 struct bpf_security_struct *bpfsec = map->security;
7017
7018 map->security = NULL;
7019 kfree(bpfsec);
7020 }
7021
selinux_bpf_prog_load(struct bpf_prog * prog,union bpf_attr * attr,struct bpf_token * token,bool kernel)7022 static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
7023 struct bpf_token *token, bool kernel)
7024 {
7025 struct bpf_security_struct *bpfsec;
7026
7027 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
7028 if (!bpfsec)
7029 return -ENOMEM;
7030
7031 bpfsec->sid = current_sid();
7032 prog->aux->security = bpfsec;
7033
7034 return 0;
7035 }
7036
selinux_bpf_prog_free(struct bpf_prog * prog)7037 static void selinux_bpf_prog_free(struct bpf_prog *prog)
7038 {
7039 struct bpf_security_struct *bpfsec = prog->aux->security;
7040
7041 prog->aux->security = NULL;
7042 kfree(bpfsec);
7043 }
7044
selinux_bpf_token_create(struct bpf_token * token,union bpf_attr * attr,const struct path * path)7045 static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
7046 const struct path *path)
7047 {
7048 struct bpf_security_struct *bpfsec;
7049
7050 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
7051 if (!bpfsec)
7052 return -ENOMEM;
7053
7054 bpfsec->sid = current_sid();
7055 token->security = bpfsec;
7056
7057 return 0;
7058 }
7059
selinux_bpf_token_free(struct bpf_token * token)7060 static void selinux_bpf_token_free(struct bpf_token *token)
7061 {
7062 struct bpf_security_struct *bpfsec = token->security;
7063
7064 token->security = NULL;
7065 kfree(bpfsec);
7066 }
7067 #endif
7068
7069 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
7070 .lbs_cred = sizeof(struct task_security_struct),
7071 .lbs_file = sizeof(struct file_security_struct),
7072 .lbs_inode = sizeof(struct inode_security_struct),
7073 .lbs_ipc = sizeof(struct ipc_security_struct),
7074 .lbs_key = sizeof(struct key_security_struct),
7075 .lbs_msg_msg = sizeof(struct msg_security_struct),
7076 #ifdef CONFIG_PERF_EVENTS
7077 .lbs_perf_event = sizeof(struct perf_event_security_struct),
7078 #endif
7079 .lbs_sock = sizeof(struct sk_security_struct),
7080 .lbs_superblock = sizeof(struct superblock_security_struct),
7081 .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS,
7082 .lbs_tun_dev = sizeof(struct tun_security_struct),
7083 .lbs_ib = sizeof(struct ib_security_struct),
7084 };
7085
7086 #ifdef CONFIG_PERF_EVENTS
selinux_perf_event_open(int type)7087 static int selinux_perf_event_open(int type)
7088 {
7089 u32 requested, sid = current_sid();
7090
7091 if (type == PERF_SECURITY_OPEN)
7092 requested = PERF_EVENT__OPEN;
7093 else if (type == PERF_SECURITY_CPU)
7094 requested = PERF_EVENT__CPU;
7095 else if (type == PERF_SECURITY_KERNEL)
7096 requested = PERF_EVENT__KERNEL;
7097 else if (type == PERF_SECURITY_TRACEPOINT)
7098 requested = PERF_EVENT__TRACEPOINT;
7099 else
7100 return -EINVAL;
7101
7102 return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
7103 requested, NULL);
7104 }
7105
selinux_perf_event_alloc(struct perf_event * event)7106 static int selinux_perf_event_alloc(struct perf_event *event)
7107 {
7108 struct perf_event_security_struct *perfsec;
7109
7110 perfsec = selinux_perf_event(event->security);
7111 perfsec->sid = current_sid();
7112
7113 return 0;
7114 }
7115
selinux_perf_event_read(struct perf_event * event)7116 static int selinux_perf_event_read(struct perf_event *event)
7117 {
7118 struct perf_event_security_struct *perfsec = event->security;
7119 u32 sid = current_sid();
7120
7121 return avc_has_perm(sid, perfsec->sid,
7122 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7123 }
7124
selinux_perf_event_write(struct perf_event * event)7125 static int selinux_perf_event_write(struct perf_event *event)
7126 {
7127 struct perf_event_security_struct *perfsec = event->security;
7128 u32 sid = current_sid();
7129
7130 return avc_has_perm(sid, perfsec->sid,
7131 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7132 }
7133 #endif
7134
7135 #ifdef CONFIG_IO_URING
7136 /**
7137 * selinux_uring_override_creds - check the requested cred override
7138 * @new: the target creds
7139 *
7140 * Check to see if the current task is allowed to override it's credentials
7141 * to service an io_uring operation.
7142 */
selinux_uring_override_creds(const struct cred * new)7143 static int selinux_uring_override_creds(const struct cred *new)
7144 {
7145 return avc_has_perm(current_sid(), cred_sid(new),
7146 SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
7147 }
7148
7149 /**
7150 * selinux_uring_sqpoll - check if a io_uring polling thread can be created
7151 *
7152 * Check to see if the current task is allowed to create a new io_uring
7153 * kernel polling thread.
7154 */
selinux_uring_sqpoll(void)7155 static int selinux_uring_sqpoll(void)
7156 {
7157 u32 sid = current_sid();
7158
7159 return avc_has_perm(sid, sid,
7160 SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
7161 }
7162
7163 /**
7164 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
7165 * @ioucmd: the io_uring command structure
7166 *
7167 * Check to see if the current domain is allowed to execute an
7168 * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
7169 *
7170 */
selinux_uring_cmd(struct io_uring_cmd * ioucmd)7171 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
7172 {
7173 struct file *file = ioucmd->file;
7174 struct inode *inode = file_inode(file);
7175 struct inode_security_struct *isec = selinux_inode(inode);
7176 struct common_audit_data ad;
7177
7178 ad.type = LSM_AUDIT_DATA_FILE;
7179 ad.u.file = file;
7180
7181 return avc_has_perm(current_sid(), isec->sid,
7182 SECCLASS_IO_URING, IO_URING__CMD, &ad);
7183 }
7184
7185 /**
7186 * selinux_uring_allowed - check if io_uring_setup() can be called
7187 *
7188 * Check to see if the current task is allowed to call io_uring_setup().
7189 */
selinux_uring_allowed(void)7190 static int selinux_uring_allowed(void)
7191 {
7192 u32 sid = current_sid();
7193
7194 return avc_has_perm(sid, sid, SECCLASS_IO_URING, IO_URING__ALLOWED,
7195 NULL);
7196 }
7197 #endif /* CONFIG_IO_URING */
7198
7199 static const struct lsm_id selinux_lsmid = {
7200 .name = "selinux",
7201 .id = LSM_ID_SELINUX,
7202 };
7203
7204 /*
7205 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7206 * 1. any hooks that don't belong to (2.) or (3.) below,
7207 * 2. hooks that both access structures allocated by other hooks, and allocate
7208 * structures that can be later accessed by other hooks (mostly "cloning"
7209 * hooks),
7210 * 3. hooks that only allocate structures that can be later accessed by other
7211 * hooks ("allocating" hooks).
7212 *
7213 * Please follow block comment delimiters in the list to keep this order.
7214 */
7215 static struct security_hook_list selinux_hooks[] __ro_after_init = {
7216 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7217 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7218 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7219 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7220
7221 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7222 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7223 LSM_HOOK_INIT(capget, selinux_capget),
7224 LSM_HOOK_INIT(capset, selinux_capset),
7225 LSM_HOOK_INIT(capable, selinux_capable),
7226 LSM_HOOK_INIT(quotactl, selinux_quotactl),
7227 LSM_HOOK_INIT(quota_on, selinux_quota_on),
7228 LSM_HOOK_INIT(syslog, selinux_syslog),
7229 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7230
7231 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7232
7233 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7234 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7235 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7236
7237 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7238 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7239 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7240 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7241 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7242 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7243 LSM_HOOK_INIT(sb_mount, selinux_mount),
7244 LSM_HOOK_INIT(sb_umount, selinux_umount),
7245 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7246 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7247
7248 LSM_HOOK_INIT(move_mount, selinux_move_mount),
7249
7250 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7251 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7252
7253 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7254 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7255 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7256 LSM_HOOK_INIT(inode_create, selinux_inode_create),
7257 LSM_HOOK_INIT(inode_link, selinux_inode_link),
7258 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7259 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7260 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7261 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7262 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7263 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7264 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7265 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7266 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7267 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7268 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7269 LSM_HOOK_INIT(inode_xattr_skipcap, selinux_inode_xattr_skipcap),
7270 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7271 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7272 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7273 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7274 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7275 LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7276 LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7277 LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7278 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7279 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7280 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7281 LSM_HOOK_INIT(inode_getlsmprop, selinux_inode_getlsmprop),
7282 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7283 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7284 LSM_HOOK_INIT(path_notify, selinux_path_notify),
7285
7286 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7287
7288 LSM_HOOK_INIT(file_permission, selinux_file_permission),
7289 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7290 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7291 LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat),
7292 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7293 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7294 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7295 LSM_HOOK_INIT(file_lock, selinux_file_lock),
7296 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7297 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7298 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7299 LSM_HOOK_INIT(file_receive, selinux_file_receive),
7300
7301 LSM_HOOK_INIT(file_open, selinux_file_open),
7302
7303 LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7304 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7305 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7306 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7307 LSM_HOOK_INIT(cred_getlsmprop, selinux_cred_getlsmprop),
7308 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7309 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7310 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7311 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7312 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7313 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7314 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7315 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7316 LSM_HOOK_INIT(current_getlsmprop_subj, selinux_current_getlsmprop_subj),
7317 LSM_HOOK_INIT(task_getlsmprop_obj, selinux_task_getlsmprop_obj),
7318 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7319 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7320 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7321 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7322 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7323 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7324 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7325 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7326 LSM_HOOK_INIT(task_kill, selinux_task_kill),
7327 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7328 LSM_HOOK_INIT(userns_create, selinux_userns_create),
7329
7330 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7331 LSM_HOOK_INIT(ipc_getlsmprop, selinux_ipc_getlsmprop),
7332
7333 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7334 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7335 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7336 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7337
7338 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7339 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7340 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7341
7342 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7343 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7344 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7345
7346 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7347
7348 LSM_HOOK_INIT(getselfattr, selinux_getselfattr),
7349 LSM_HOOK_INIT(setselfattr, selinux_setselfattr),
7350 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7351 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7352
7353 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7354 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7355 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7356 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7357 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7358 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7359
7360 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7361 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7362
7363 LSM_HOOK_INIT(socket_create, selinux_socket_create),
7364 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7365 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7366 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7367 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7368 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7369 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7370 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7371 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7372 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7373 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7374 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7375 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7376 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7377 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7378 LSM_HOOK_INIT(socket_getpeersec_stream,
7379 selinux_socket_getpeersec_stream),
7380 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7381 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7382 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7383 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7384 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7385 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7386 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7387 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7388 LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7389 LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow),
7390 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7391 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7392 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7393 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7394 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7395 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7396 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7397 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7398 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7399 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7400 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7401 #ifdef CONFIG_SECURITY_INFINIBAND
7402 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7403 LSM_HOOK_INIT(ib_endport_manage_subnet,
7404 selinux_ib_endport_manage_subnet),
7405 #endif
7406 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7407 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7408 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7409 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7410 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7411 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7412 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7413 selinux_xfrm_state_pol_flow_match),
7414 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7415 #endif
7416
7417 #ifdef CONFIG_KEYS
7418 LSM_HOOK_INIT(key_permission, selinux_key_permission),
7419 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7420 #ifdef CONFIG_KEY_NOTIFICATIONS
7421 LSM_HOOK_INIT(watch_key, selinux_watch_key),
7422 #endif
7423 #endif
7424
7425 #ifdef CONFIG_AUDIT
7426 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7427 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7428 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7429 #endif
7430
7431 #ifdef CONFIG_BPF_SYSCALL
7432 LSM_HOOK_INIT(bpf, selinux_bpf),
7433 LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7434 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7435 LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free),
7436 LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free),
7437 LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free),
7438 #endif
7439
7440 #ifdef CONFIG_PERF_EVENTS
7441 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7442 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7443 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7444 #endif
7445
7446 #ifdef CONFIG_IO_URING
7447 LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7448 LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7449 LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7450 LSM_HOOK_INIT(uring_allowed, selinux_uring_allowed),
7451 #endif
7452
7453 /*
7454 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7455 */
7456 LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount),
7457 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7458 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7459 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7460 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7461 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7462 #endif
7463
7464 /*
7465 * PUT "ALLOCATING" HOOKS HERE
7466 */
7467 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7468 LSM_HOOK_INIT(msg_queue_alloc_security,
7469 selinux_msg_queue_alloc_security),
7470 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7471 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7472 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7473 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7474 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7475 LSM_HOOK_INIT(lsmprop_to_secctx, selinux_lsmprop_to_secctx),
7476 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7477 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7478 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7479 #ifdef CONFIG_SECURITY_INFINIBAND
7480 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7481 #endif
7482 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7483 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7484 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7485 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7486 selinux_xfrm_state_alloc_acquire),
7487 #endif
7488 #ifdef CONFIG_KEYS
7489 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7490 #endif
7491 #ifdef CONFIG_AUDIT
7492 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7493 #endif
7494 #ifdef CONFIG_BPF_SYSCALL
7495 LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create),
7496 LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load),
7497 LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create),
7498 #endif
7499 #ifdef CONFIG_PERF_EVENTS
7500 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7501 #endif
7502 };
7503
selinux_init(void)7504 static __init int selinux_init(void)
7505 {
7506 pr_info("SELinux: Initializing.\n");
7507
7508 memset(&selinux_state, 0, sizeof(selinux_state));
7509 enforcing_set(selinux_enforcing_boot);
7510 selinux_avc_init();
7511 mutex_init(&selinux_state.status_lock);
7512 mutex_init(&selinux_state.policy_mutex);
7513
7514 /* Set the security state for the initial task. */
7515 cred_init_security();
7516
7517 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7518 if (!default_noexec)
7519 pr_notice("SELinux: virtual memory is executable by default\n");
7520
7521 avc_init();
7522
7523 avtab_cache_init();
7524
7525 ebitmap_cache_init();
7526
7527 hashtab_cache_init();
7528
7529 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
7530 &selinux_lsmid);
7531
7532 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7533 panic("SELinux: Unable to register AVC netcache callback\n");
7534
7535 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7536 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7537
7538 if (selinux_enforcing_boot)
7539 pr_debug("SELinux: Starting in enforcing mode\n");
7540 else
7541 pr_debug("SELinux: Starting in permissive mode\n");
7542
7543 fs_validate_description("selinux", selinux_fs_parameters);
7544
7545 return 0;
7546 }
7547
delayed_superblock_init(struct super_block * sb,void * unused)7548 static void delayed_superblock_init(struct super_block *sb, void *unused)
7549 {
7550 selinux_set_mnt_opts(sb, NULL, 0, NULL);
7551 }
7552
selinux_complete_init(void)7553 void selinux_complete_init(void)
7554 {
7555 pr_debug("SELinux: Completing initialization.\n");
7556
7557 /* Set up any superblocks initialized prior to the policy load. */
7558 pr_debug("SELinux: Setting up existing superblocks.\n");
7559 iterate_supers(delayed_superblock_init, NULL);
7560 }
7561
7562 /* SELinux requires early initialization in order to label
7563 all processes and objects when they are created. */
7564 DEFINE_LSM(selinux) = {
7565 .name = "selinux",
7566 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7567 .enabled = &selinux_enabled_boot,
7568 .blobs = &selinux_blob_sizes,
7569 .init = selinux_init,
7570 };
7571
7572 #if defined(CONFIG_NETFILTER)
7573 static const struct nf_hook_ops selinux_nf_ops[] = {
7574 {
7575 .hook = selinux_ip_postroute,
7576 .pf = NFPROTO_IPV4,
7577 .hooknum = NF_INET_POST_ROUTING,
7578 .priority = NF_IP_PRI_SELINUX_LAST,
7579 },
7580 {
7581 .hook = selinux_ip_forward,
7582 .pf = NFPROTO_IPV4,
7583 .hooknum = NF_INET_FORWARD,
7584 .priority = NF_IP_PRI_SELINUX_FIRST,
7585 },
7586 {
7587 .hook = selinux_ip_output,
7588 .pf = NFPROTO_IPV4,
7589 .hooknum = NF_INET_LOCAL_OUT,
7590 .priority = NF_IP_PRI_SELINUX_FIRST,
7591 },
7592 #if IS_ENABLED(CONFIG_IPV6)
7593 {
7594 .hook = selinux_ip_postroute,
7595 .pf = NFPROTO_IPV6,
7596 .hooknum = NF_INET_POST_ROUTING,
7597 .priority = NF_IP6_PRI_SELINUX_LAST,
7598 },
7599 {
7600 .hook = selinux_ip_forward,
7601 .pf = NFPROTO_IPV6,
7602 .hooknum = NF_INET_FORWARD,
7603 .priority = NF_IP6_PRI_SELINUX_FIRST,
7604 },
7605 {
7606 .hook = selinux_ip_output,
7607 .pf = NFPROTO_IPV6,
7608 .hooknum = NF_INET_LOCAL_OUT,
7609 .priority = NF_IP6_PRI_SELINUX_FIRST,
7610 },
7611 #endif /* IPV6 */
7612 };
7613
selinux_nf_register(struct net * net)7614 static int __net_init selinux_nf_register(struct net *net)
7615 {
7616 return nf_register_net_hooks(net, selinux_nf_ops,
7617 ARRAY_SIZE(selinux_nf_ops));
7618 }
7619
selinux_nf_unregister(struct net * net)7620 static void __net_exit selinux_nf_unregister(struct net *net)
7621 {
7622 nf_unregister_net_hooks(net, selinux_nf_ops,
7623 ARRAY_SIZE(selinux_nf_ops));
7624 }
7625
7626 static struct pernet_operations selinux_net_ops = {
7627 .init = selinux_nf_register,
7628 .exit = selinux_nf_unregister,
7629 };
7630
selinux_nf_ip_init(void)7631 static int __init selinux_nf_ip_init(void)
7632 {
7633 int err;
7634
7635 if (!selinux_enabled_boot)
7636 return 0;
7637
7638 pr_debug("SELinux: Registering netfilter hooks\n");
7639
7640 err = register_pernet_subsys(&selinux_net_ops);
7641 if (err)
7642 panic("SELinux: register_pernet_subsys: error %d\n", err);
7643
7644 return 0;
7645 }
7646 __initcall(selinux_nf_ip_init);
7647 #endif /* CONFIG_NETFILTER */
7648