Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * NSA Security-Enhanced Linux (SELinux) security module | |
3 | * | |
4 | * This file contains the SELinux hook function implementations. | |
5 | * | |
6 | * Authors: Stephen Smalley, <sds@epoch.ncsc.mil> | |
828dfe1d EP |
7 | * Chris Vance, <cvance@nai.com> |
8 | * Wayne Salamon, <wsalamon@nai.com> | |
9 | * James Morris <jmorris@redhat.com> | |
1da177e4 LT |
10 | * |
11 | * Copyright (C) 2001,2002 Networks Associates Technology, Inc. | |
2069f457 EP |
12 | * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> |
13 | * Eric Paris <eparis@redhat.com> | |
1da177e4 | 14 | * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. |
828dfe1d | 15 | * <dgoeddel@trustedcs.com> |
ed6d76e4 | 16 | * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. |
82c21bfa | 17 | * Paul Moore <paul@paul-moore.com> |
788e7dd4 | 18 | * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. |
828dfe1d | 19 | * Yuichi Nakamura <ynakam@hitachisoft.jp> |
1da177e4 LT |
20 | * |
21 | * This program is free software; you can redistribute it and/or modify | |
22 | * it under the terms of the GNU General Public License version 2, | |
828dfe1d | 23 | * as published by the Free Software Foundation. |
1da177e4 LT |
24 | */ |
25 | ||
1da177e4 | 26 | #include <linux/init.h> |
0b24dcb7 | 27 | #include <linux/kd.h> |
1da177e4 | 28 | #include <linux/kernel.h> |
0d094efe | 29 | #include <linux/tracehook.h> |
1da177e4 LT |
30 | #include <linux/errno.h> |
31 | #include <linux/sched.h> | |
3c4ed7bd | 32 | #include <linux/lsm_hooks.h> |
1da177e4 LT |
33 | #include <linux/xattr.h> |
34 | #include <linux/capability.h> | |
35 | #include <linux/unistd.h> | |
36 | #include <linux/mm.h> | |
37 | #include <linux/mman.h> | |
38 | #include <linux/slab.h> | |
39 | #include <linux/pagemap.h> | |
0b24dcb7 | 40 | #include <linux/proc_fs.h> |
1da177e4 | 41 | #include <linux/swap.h> |
1da177e4 LT |
42 | #include <linux/spinlock.h> |
43 | #include <linux/syscalls.h> | |
2a7dba39 | 44 | #include <linux/dcache.h> |
1da177e4 | 45 | #include <linux/file.h> |
9f3acc31 | 46 | #include <linux/fdtable.h> |
1da177e4 LT |
47 | #include <linux/namei.h> |
48 | #include <linux/mount.h> | |
1da177e4 LT |
49 | #include <linux/netfilter_ipv4.h> |
50 | #include <linux/netfilter_ipv6.h> | |
51 | #include <linux/tty.h> | |
52 | #include <net/icmp.h> | |
227b60f5 | 53 | #include <net/ip.h> /* for local_port_range[] */ |
1da177e4 | 54 | #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ |
47180068 | 55 | #include <net/inet_connection_sock.h> |
220deb96 | 56 | #include <net/net_namespace.h> |
d621d35e | 57 | #include <net/netlabel.h> |
f5269710 | 58 | #include <linux/uaccess.h> |
1da177e4 | 59 | #include <asm/ioctls.h> |
60063497 | 60 | #include <linux/atomic.h> |
1da177e4 LT |
61 | #include <linux/bitops.h> |
62 | #include <linux/interrupt.h> | |
63 | #include <linux/netdevice.h> /* for network interface checks */ | |
77954983 | 64 | #include <net/netlink.h> |
1da177e4 LT |
65 | #include <linux/tcp.h> |
66 | #include <linux/udp.h> | |
2ee92d46 | 67 | #include <linux/dccp.h> |
1da177e4 LT |
68 | #include <linux/quota.h> |
69 | #include <linux/un.h> /* for Unix socket types */ | |
70 | #include <net/af_unix.h> /* for Unix socket types */ | |
71 | #include <linux/parser.h> | |
72 | #include <linux/nfs_mount.h> | |
73 | #include <net/ipv6.h> | |
74 | #include <linux/hugetlb.h> | |
75 | #include <linux/personality.h> | |
1da177e4 | 76 | #include <linux/audit.h> |
6931dfc9 | 77 | #include <linux/string.h> |
877ce7c1 | 78 | #include <linux/selinux.h> |
23970741 | 79 | #include <linux/mutex.h> |
f06febc9 | 80 | #include <linux/posix-timers.h> |
00234592 | 81 | #include <linux/syslog.h> |
3486740a | 82 | #include <linux/user_namespace.h> |
44fc7ea0 | 83 | #include <linux/export.h> |
40401530 AV |
84 | #include <linux/msg.h> |
85 | #include <linux/shm.h> | |
1da177e4 LT |
86 | |
87 | #include "avc.h" | |
88 | #include "objsec.h" | |
89 | #include "netif.h" | |
224dfbd8 | 90 | #include "netnode.h" |
3e112172 | 91 | #include "netport.h" |
d28d1e08 | 92 | #include "xfrm.h" |
c60475bf | 93 | #include "netlabel.h" |
9d57a7f9 | 94 | #include "audit.h" |
7b98a585 | 95 | #include "avc_ss.h" |
1da177e4 | 96 | |
d621d35e | 97 | /* SECMARK reference count */ |
56a4ca99 | 98 | static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); |
d621d35e | 99 | |
1da177e4 | 100 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
828dfe1d | 101 | int selinux_enforcing; |
1da177e4 LT |
102 | |
103 | static int __init enforcing_setup(char *str) | |
104 | { | |
f5269710 | 105 | unsigned long enforcing; |
29707b20 | 106 | if (!kstrtoul(str, 0, &enforcing)) |
f5269710 | 107 | selinux_enforcing = enforcing ? 1 : 0; |
1da177e4 LT |
108 | return 1; |
109 | } | |
110 | __setup("enforcing=", enforcing_setup); | |
111 | #endif | |
112 | ||
113 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM | |
114 | int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; | |
115 | ||
116 | static int __init selinux_enabled_setup(char *str) | |
117 | { | |
f5269710 | 118 | unsigned long enabled; |
29707b20 | 119 | if (!kstrtoul(str, 0, &enabled)) |
f5269710 | 120 | selinux_enabled = enabled ? 1 : 0; |
1da177e4 LT |
121 | return 1; |
122 | } | |
123 | __setup("selinux=", selinux_enabled_setup); | |
30d55280 SS |
124 | #else |
125 | int selinux_enabled = 1; | |
1da177e4 LT |
126 | #endif |
127 | ||
e18b890b | 128 | static struct kmem_cache *sel_inode_cache; |
63205654 | 129 | static struct kmem_cache *file_security_cache; |
7cae7e26 | 130 | |
d621d35e PM |
131 | /** |
132 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
133 | * | |
134 | * Description: | |
135 | * This function checks the SECMARK reference counter to see if any SECMARK | |
136 | * targets are currently configured, if the reference counter is greater than | |
137 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
2be4d74f CP |
138 | * enabled, false (0) if SECMARK is disabled. If the always_check_network |
139 | * policy capability is enabled, SECMARK is always considered enabled. | |
d621d35e PM |
140 | * |
141 | */ | |
142 | static int selinux_secmark_enabled(void) | |
143 | { | |
2be4d74f CP |
144 | return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount)); |
145 | } | |
146 | ||
147 | /** | |
148 | * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled | |
149 | * | |
150 | * Description: | |
151 | * This function checks if NetLabel or labeled IPSEC is enabled. Returns true | |
152 | * (1) if any are enabled or false (0) if neither are enabled. If the | |
153 | * always_check_network policy capability is enabled, peer labeling | |
154 | * is always considered enabled. | |
155 | * | |
156 | */ | |
157 | static int selinux_peerlbl_enabled(void) | |
158 | { | |
159 | return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled()); | |
d621d35e PM |
160 | } |
161 | ||
615e51fd PM |
162 | static int selinux_netcache_avc_callback(u32 event) |
163 | { | |
164 | if (event == AVC_CALLBACK_RESET) { | |
165 | sel_netif_flush(); | |
166 | sel_netnode_flush(); | |
167 | sel_netport_flush(); | |
168 | synchronize_net(); | |
169 | } | |
170 | return 0; | |
171 | } | |
172 | ||
d84f4f99 DH |
173 | /* |
174 | * initialise the security for the init task | |
175 | */ | |
176 | static void cred_init_security(void) | |
1da177e4 | 177 | { |
3b11a1de | 178 | struct cred *cred = (struct cred *) current->real_cred; |
1da177e4 LT |
179 | struct task_security_struct *tsec; |
180 | ||
89d155ef | 181 | tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); |
1da177e4 | 182 | if (!tsec) |
d84f4f99 | 183 | panic("SELinux: Failed to initialize initial task.\n"); |
1da177e4 | 184 | |
d84f4f99 | 185 | tsec->osid = tsec->sid = SECINITSID_KERNEL; |
f1752eec | 186 | cred->security = tsec; |
1da177e4 LT |
187 | } |
188 | ||
88e67f3b DH |
189 | /* |
190 | * get the security ID of a set of credentials | |
191 | */ | |
192 | static inline u32 cred_sid(const struct cred *cred) | |
193 | { | |
194 | const struct task_security_struct *tsec; | |
195 | ||
196 | tsec = cred->security; | |
197 | return tsec->sid; | |
198 | } | |
199 | ||
275bb41e | 200 | /* |
3b11a1de | 201 | * get the objective security ID of a task |
275bb41e DH |
202 | */ |
203 | static inline u32 task_sid(const struct task_struct *task) | |
204 | { | |
275bb41e DH |
205 | u32 sid; |
206 | ||
207 | rcu_read_lock(); | |
88e67f3b | 208 | sid = cred_sid(__task_cred(task)); |
275bb41e DH |
209 | rcu_read_unlock(); |
210 | return sid; | |
211 | } | |
212 | ||
213 | /* | |
3b11a1de | 214 | * get the subjective security ID of the current task |
275bb41e DH |
215 | */ |
216 | static inline u32 current_sid(void) | |
217 | { | |
5fb49870 | 218 | const struct task_security_struct *tsec = current_security(); |
275bb41e DH |
219 | |
220 | return tsec->sid; | |
221 | } | |
222 | ||
88e67f3b DH |
223 | /* Allocate and free functions for each kind of security blob. */ |
224 | ||
1da177e4 LT |
225 | static int inode_alloc_security(struct inode *inode) |
226 | { | |
1da177e4 | 227 | struct inode_security_struct *isec; |
275bb41e | 228 | u32 sid = current_sid(); |
1da177e4 | 229 | |
a02fe132 | 230 | isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); |
1da177e4 LT |
231 | if (!isec) |
232 | return -ENOMEM; | |
233 | ||
23970741 | 234 | mutex_init(&isec->lock); |
1da177e4 | 235 | INIT_LIST_HEAD(&isec->list); |
1da177e4 LT |
236 | isec->inode = inode; |
237 | isec->sid = SECINITSID_UNLABELED; | |
238 | isec->sclass = SECCLASS_FILE; | |
275bb41e | 239 | isec->task_sid = sid; |
1da177e4 LT |
240 | inode->i_security = isec; |
241 | ||
242 | return 0; | |
243 | } | |
244 | ||
5d226df4 AG |
245 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); |
246 | ||
247 | /* | |
248 | * Try reloading inode security labels that have been marked as invalid. The | |
249 | * @may_sleep parameter indicates when sleeping and thus reloading labels is | |
250 | * allowed; when set to false, returns ERR_PTR(-ECHILD) when the label is | |
251 | * invalid. The @opt_dentry parameter should be set to a dentry of the inode; | |
252 | * when no dentry is available, set it to NULL instead. | |
253 | */ | |
254 | static int __inode_security_revalidate(struct inode *inode, | |
255 | struct dentry *opt_dentry, | |
256 | bool may_sleep) | |
257 | { | |
258 | struct inode_security_struct *isec = inode->i_security; | |
259 | ||
260 | might_sleep_if(may_sleep); | |
261 | ||
1ac42476 | 262 | if (ss_initialized && isec->initialized != LABEL_INITIALIZED) { |
5d226df4 AG |
263 | if (!may_sleep) |
264 | return -ECHILD; | |
265 | ||
266 | /* | |
267 | * Try reloading the inode security label. This will fail if | |
268 | * @opt_dentry is NULL and no dentry for this inode can be | |
269 | * found; in that case, continue using the old label. | |
270 | */ | |
271 | inode_doinit_with_dentry(inode, opt_dentry); | |
272 | } | |
273 | return 0; | |
274 | } | |
275 | ||
5d226df4 AG |
276 | static struct inode_security_struct *inode_security_novalidate(struct inode *inode) |
277 | { | |
278 | return inode->i_security; | |
279 | } | |
280 | ||
281 | static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) | |
282 | { | |
283 | int error; | |
284 | ||
285 | error = __inode_security_revalidate(inode, NULL, !rcu); | |
286 | if (error) | |
287 | return ERR_PTR(error); | |
288 | return inode->i_security; | |
289 | } | |
290 | ||
83da53c5 AG |
291 | /* |
292 | * Get the security label of an inode. | |
293 | */ | |
294 | static struct inode_security_struct *inode_security(struct inode *inode) | |
295 | { | |
5d226df4 | 296 | __inode_security_revalidate(inode, NULL, true); |
83da53c5 AG |
297 | return inode->i_security; |
298 | } | |
299 | ||
2c97165b PM |
300 | static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) |
301 | { | |
302 | struct inode *inode = d_backing_inode(dentry); | |
303 | ||
304 | return inode->i_security; | |
305 | } | |
306 | ||
83da53c5 AG |
307 | /* |
308 | * Get the security label of a dentry's backing inode. | |
309 | */ | |
310 | static struct inode_security_struct *backing_inode_security(struct dentry *dentry) | |
311 | { | |
312 | struct inode *inode = d_backing_inode(dentry); | |
313 | ||
5d226df4 | 314 | __inode_security_revalidate(inode, dentry, true); |
83da53c5 AG |
315 | return inode->i_security; |
316 | } | |
317 | ||
3dc91d43 SR |
318 | static void inode_free_rcu(struct rcu_head *head) |
319 | { | |
320 | struct inode_security_struct *isec; | |
321 | ||
322 | isec = container_of(head, struct inode_security_struct, rcu); | |
323 | kmem_cache_free(sel_inode_cache, isec); | |
324 | } | |
325 | ||
1da177e4 LT |
326 | static void inode_free_security(struct inode *inode) |
327 | { | |
328 | struct inode_security_struct *isec = inode->i_security; | |
329 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
330 | ||
9629d04a WL |
331 | /* |
332 | * As not all inode security structures are in a list, we check for | |
333 | * empty list outside of the lock to make sure that we won't waste | |
334 | * time taking a lock doing nothing. | |
335 | * | |
336 | * The list_del_init() function can be safely called more than once. | |
337 | * It should not be possible for this function to be called with | |
338 | * concurrent list_add(), but for better safety against future changes | |
339 | * in the code, we use list_empty_careful() here. | |
340 | */ | |
341 | if (!list_empty_careful(&isec->list)) { | |
342 | spin_lock(&sbsec->isec_lock); | |
1da177e4 | 343 | list_del_init(&isec->list); |
9629d04a WL |
344 | spin_unlock(&sbsec->isec_lock); |
345 | } | |
1da177e4 | 346 | |
3dc91d43 SR |
347 | /* |
348 | * The inode may still be referenced in a path walk and | |
349 | * a call to selinux_inode_permission() can be made | |
350 | * after inode_free_security() is called. Ideally, the VFS | |
351 | * wouldn't do this, but fixing that is a much harder | |
352 | * job. For now, simply free the i_security via RCU, and | |
353 | * leave the current inode->i_security pointer intact. | |
354 | * The inode will be freed after the RCU grace period too. | |
355 | */ | |
356 | call_rcu(&isec->rcu, inode_free_rcu); | |
1da177e4 LT |
357 | } |
358 | ||
359 | static int file_alloc_security(struct file *file) | |
360 | { | |
1da177e4 | 361 | struct file_security_struct *fsec; |
275bb41e | 362 | u32 sid = current_sid(); |
1da177e4 | 363 | |
63205654 | 364 | fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL); |
1da177e4 LT |
365 | if (!fsec) |
366 | return -ENOMEM; | |
367 | ||
275bb41e DH |
368 | fsec->sid = sid; |
369 | fsec->fown_sid = sid; | |
1da177e4 LT |
370 | file->f_security = fsec; |
371 | ||
372 | return 0; | |
373 | } | |
374 | ||
375 | static void file_free_security(struct file *file) | |
376 | { | |
377 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 | 378 | file->f_security = NULL; |
63205654 | 379 | kmem_cache_free(file_security_cache, fsec); |
1da177e4 LT |
380 | } |
381 | ||
382 | static int superblock_alloc_security(struct super_block *sb) | |
383 | { | |
384 | struct superblock_security_struct *sbsec; | |
385 | ||
89d155ef | 386 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
387 | if (!sbsec) |
388 | return -ENOMEM; | |
389 | ||
bc7e982b | 390 | mutex_init(&sbsec->lock); |
1da177e4 LT |
391 | INIT_LIST_HEAD(&sbsec->isec_head); |
392 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
393 | sbsec->sb = sb; |
394 | sbsec->sid = SECINITSID_UNLABELED; | |
395 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 396 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
397 | sb->s_security = sbsec; |
398 | ||
399 | return 0; | |
400 | } | |
401 | ||
402 | static void superblock_free_security(struct super_block *sb) | |
403 | { | |
404 | struct superblock_security_struct *sbsec = sb->s_security; | |
1da177e4 LT |
405 | sb->s_security = NULL; |
406 | kfree(sbsec); | |
407 | } | |
408 | ||
1da177e4 LT |
409 | /* The file system's label must be initialized prior to use. */ |
410 | ||
eb9ae686 | 411 | static const char *labeling_behaviors[7] = { |
1da177e4 LT |
412 | "uses xattr", |
413 | "uses transition SIDs", | |
414 | "uses task SIDs", | |
415 | "uses genfs_contexts", | |
416 | "not configured for labeling", | |
417 | "uses mountpoint labeling", | |
eb9ae686 | 418 | "uses native labeling", |
1da177e4 LT |
419 | }; |
420 | ||
1da177e4 LT |
421 | static inline int inode_doinit(struct inode *inode) |
422 | { | |
423 | return inode_doinit_with_dentry(inode, NULL); | |
424 | } | |
425 | ||
426 | enum { | |
31e87930 | 427 | Opt_error = -1, |
1da177e4 LT |
428 | Opt_context = 1, |
429 | Opt_fscontext = 2, | |
c9180a57 EP |
430 | Opt_defcontext = 3, |
431 | Opt_rootcontext = 4, | |
11689d47 | 432 | Opt_labelsupport = 5, |
d355987f | 433 | Opt_nextmntopt = 6, |
1da177e4 LT |
434 | }; |
435 | ||
d355987f EP |
436 | #define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) |
437 | ||
a447c093 | 438 | static const match_table_t tokens = { |
832cbd9a EP |
439 | {Opt_context, CONTEXT_STR "%s"}, |
440 | {Opt_fscontext, FSCONTEXT_STR "%s"}, | |
441 | {Opt_defcontext, DEFCONTEXT_STR "%s"}, | |
442 | {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, | |
11689d47 | 443 | {Opt_labelsupport, LABELSUPP_STR}, |
31e87930 | 444 | {Opt_error, NULL}, |
1da177e4 LT |
445 | }; |
446 | ||
447 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
448 | ||
c312feb2 EP |
449 | static int may_context_mount_sb_relabel(u32 sid, |
450 | struct superblock_security_struct *sbsec, | |
275bb41e | 451 | const struct cred *cred) |
c312feb2 | 452 | { |
275bb41e | 453 | const struct task_security_struct *tsec = cred->security; |
c312feb2 EP |
454 | int rc; |
455 | ||
456 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
457 | FILESYSTEM__RELABELFROM, NULL); | |
458 | if (rc) | |
459 | return rc; | |
460 | ||
461 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, | |
462 | FILESYSTEM__RELABELTO, NULL); | |
463 | return rc; | |
464 | } | |
465 | ||
0808925e EP |
466 | static int may_context_mount_inode_relabel(u32 sid, |
467 | struct superblock_security_struct *sbsec, | |
275bb41e | 468 | const struct cred *cred) |
0808925e | 469 | { |
275bb41e | 470 | const struct task_security_struct *tsec = cred->security; |
0808925e EP |
471 | int rc; |
472 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
473 | FILESYSTEM__RELABELFROM, NULL); | |
474 | if (rc) | |
475 | return rc; | |
476 | ||
477 | rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
478 | FILESYSTEM__ASSOCIATE, NULL); | |
479 | return rc; | |
480 | } | |
481 | ||
b43e725d EP |
482 | static int selinux_is_sblabel_mnt(struct super_block *sb) |
483 | { | |
484 | struct superblock_security_struct *sbsec = sb->s_security; | |
485 | ||
d5f3a5f6 MS |
486 | return sbsec->behavior == SECURITY_FS_USE_XATTR || |
487 | sbsec->behavior == SECURITY_FS_USE_TRANS || | |
488 | sbsec->behavior == SECURITY_FS_USE_TASK || | |
9fc2b4b4 | 489 | sbsec->behavior == SECURITY_FS_USE_NATIVE || |
d5f3a5f6 MS |
490 | /* Special handling. Genfs but also in-core setxattr handler */ |
491 | !strcmp(sb->s_type->name, "sysfs") || | |
492 | !strcmp(sb->s_type->name, "pstore") || | |
493 | !strcmp(sb->s_type->name, "debugfs") || | |
494 | !strcmp(sb->s_type->name, "rootfs"); | |
b43e725d EP |
495 | } |
496 | ||
c9180a57 | 497 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 498 | { |
1da177e4 | 499 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 | 500 | struct dentry *root = sb->s_root; |
c6f493d6 | 501 | struct inode *root_inode = d_backing_inode(root); |
c9180a57 | 502 | int rc = 0; |
1da177e4 | 503 | |
c9180a57 EP |
504 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
505 | /* Make sure that the xattr handler exists and that no | |
506 | error other than -ENODATA is returned by getxattr on | |
507 | the root directory. -ENODATA is ok, as this may be | |
508 | the first boot of the SELinux kernel before we have | |
509 | assigned xattr values to the filesystem. */ | |
510 | if (!root_inode->i_op->getxattr) { | |
29b1deb2 LT |
511 | printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " |
512 | "xattr support\n", sb->s_id, sb->s_type->name); | |
c9180a57 EP |
513 | rc = -EOPNOTSUPP; |
514 | goto out; | |
515 | } | |
ce23e640 AV |
516 | rc = root_inode->i_op->getxattr(root, root_inode, |
517 | XATTR_NAME_SELINUX, NULL, 0); | |
c9180a57 EP |
518 | if (rc < 0 && rc != -ENODATA) { |
519 | if (rc == -EOPNOTSUPP) | |
520 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
29b1deb2 LT |
521 | "%s) has no security xattr handler\n", |
522 | sb->s_id, sb->s_type->name); | |
c9180a57 EP |
523 | else |
524 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
29b1deb2 LT |
525 | "%s) getxattr errno %d\n", sb->s_id, |
526 | sb->s_type->name, -rc); | |
c9180a57 EP |
527 | goto out; |
528 | } | |
529 | } | |
1da177e4 | 530 | |
c9180a57 | 531 | if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) |
29b1deb2 LT |
532 | printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", |
533 | sb->s_id, sb->s_type->name); | |
1da177e4 | 534 | |
eadcabc6 | 535 | sbsec->flags |= SE_SBINITIALIZED; |
b43e725d | 536 | if (selinux_is_sblabel_mnt(sb)) |
12f348b9 | 537 | sbsec->flags |= SBLABEL_MNT; |
ddd29ec6 | 538 | |
c9180a57 EP |
539 | /* Initialize the root inode. */ |
540 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 541 | |
c9180a57 EP |
542 | /* Initialize any other inodes associated with the superblock, e.g. |
543 | inodes created prior to initial policy load or inodes created | |
544 | during get_sb by a pseudo filesystem that directly | |
545 | populates itself. */ | |
546 | spin_lock(&sbsec->isec_lock); | |
547 | next_inode: | |
548 | if (!list_empty(&sbsec->isec_head)) { | |
549 | struct inode_security_struct *isec = | |
550 | list_entry(sbsec->isec_head.next, | |
551 | struct inode_security_struct, list); | |
552 | struct inode *inode = isec->inode; | |
923190d3 | 553 | list_del_init(&isec->list); |
c9180a57 EP |
554 | spin_unlock(&sbsec->isec_lock); |
555 | inode = igrab(inode); | |
556 | if (inode) { | |
557 | if (!IS_PRIVATE(inode)) | |
558 | inode_doinit(inode); | |
559 | iput(inode); | |
560 | } | |
561 | spin_lock(&sbsec->isec_lock); | |
c9180a57 EP |
562 | goto next_inode; |
563 | } | |
564 | spin_unlock(&sbsec->isec_lock); | |
565 | out: | |
566 | return rc; | |
567 | } | |
1da177e4 | 568 | |
c9180a57 EP |
569 | /* |
570 | * This function should allow an FS to ask what it's mount security | |
571 | * options were so it can use those later for submounts, displaying | |
572 | * mount options, or whatever. | |
573 | */ | |
574 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
e0007529 | 575 | struct security_mnt_opts *opts) |
c9180a57 EP |
576 | { |
577 | int rc = 0, i; | |
578 | struct superblock_security_struct *sbsec = sb->s_security; | |
579 | char *context = NULL; | |
580 | u32 len; | |
581 | char tmp; | |
1da177e4 | 582 | |
e0007529 | 583 | security_init_mnt_opts(opts); |
1da177e4 | 584 | |
0d90a7ec | 585 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
c9180a57 | 586 | return -EINVAL; |
1da177e4 | 587 | |
c9180a57 EP |
588 | if (!ss_initialized) |
589 | return -EINVAL; | |
1da177e4 | 590 | |
af8e50cc EP |
591 | /* make sure we always check enough bits to cover the mask */ |
592 | BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); | |
593 | ||
0d90a7ec | 594 | tmp = sbsec->flags & SE_MNTMASK; |
c9180a57 | 595 | /* count the number of mount options for this sb */ |
af8e50cc | 596 | for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { |
c9180a57 | 597 | if (tmp & 0x01) |
e0007529 | 598 | opts->num_mnt_opts++; |
c9180a57 EP |
599 | tmp >>= 1; |
600 | } | |
11689d47 | 601 | /* Check if the Label support flag is set */ |
0b4bdb35 | 602 | if (sbsec->flags & SBLABEL_MNT) |
11689d47 | 603 | opts->num_mnt_opts++; |
1da177e4 | 604 | |
e0007529 EP |
605 | opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); |
606 | if (!opts->mnt_opts) { | |
c9180a57 EP |
607 | rc = -ENOMEM; |
608 | goto out_free; | |
609 | } | |
1da177e4 | 610 | |
e0007529 EP |
611 | opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); |
612 | if (!opts->mnt_opts_flags) { | |
c9180a57 EP |
613 | rc = -ENOMEM; |
614 | goto out_free; | |
615 | } | |
1da177e4 | 616 | |
c9180a57 EP |
617 | i = 0; |
618 | if (sbsec->flags & FSCONTEXT_MNT) { | |
619 | rc = security_sid_to_context(sbsec->sid, &context, &len); | |
620 | if (rc) | |
621 | goto out_free; | |
e0007529 EP |
622 | opts->mnt_opts[i] = context; |
623 | opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; | |
c9180a57 EP |
624 | } |
625 | if (sbsec->flags & CONTEXT_MNT) { | |
626 | rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); | |
627 | if (rc) | |
628 | goto out_free; | |
e0007529 EP |
629 | opts->mnt_opts[i] = context; |
630 | opts->mnt_opts_flags[i++] = CONTEXT_MNT; | |
c9180a57 EP |
631 | } |
632 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
633 | rc = security_sid_to_context(sbsec->def_sid, &context, &len); | |
634 | if (rc) | |
635 | goto out_free; | |
e0007529 EP |
636 | opts->mnt_opts[i] = context; |
637 | opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
638 | } |
639 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
640 | struct dentry *root = sbsec->sb->s_root; |
641 | struct inode_security_struct *isec = backing_inode_security(root); | |
0808925e | 642 | |
c9180a57 EP |
643 | rc = security_sid_to_context(isec->sid, &context, &len); |
644 | if (rc) | |
645 | goto out_free; | |
e0007529 EP |
646 | opts->mnt_opts[i] = context; |
647 | opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; | |
c9180a57 | 648 | } |
12f348b9 | 649 | if (sbsec->flags & SBLABEL_MNT) { |
11689d47 | 650 | opts->mnt_opts[i] = NULL; |
12f348b9 | 651 | opts->mnt_opts_flags[i++] = SBLABEL_MNT; |
11689d47 | 652 | } |
1da177e4 | 653 | |
e0007529 | 654 | BUG_ON(i != opts->num_mnt_opts); |
1da177e4 | 655 | |
c9180a57 EP |
656 | return 0; |
657 | ||
658 | out_free: | |
e0007529 | 659 | security_free_mnt_opts(opts); |
c9180a57 EP |
660 | return rc; |
661 | } | |
1da177e4 | 662 | |
c9180a57 EP |
663 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
664 | u32 old_sid, u32 new_sid) | |
665 | { | |
0d90a7ec DQ |
666 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
667 | ||
c9180a57 | 668 | /* check if the old mount command had the same options */ |
0d90a7ec | 669 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
670 | if (!(sbsec->flags & flag) || |
671 | (old_sid != new_sid)) | |
672 | return 1; | |
673 | ||
674 | /* check if we were passed the same options twice, | |
675 | * aka someone passed context=a,context=b | |
676 | */ | |
0d90a7ec DQ |
677 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
678 | if (mnt_flags & flag) | |
c9180a57 EP |
679 | return 1; |
680 | return 0; | |
681 | } | |
e0007529 | 682 | |
c9180a57 EP |
683 | /* |
684 | * Allow filesystems with binary mount data to explicitly set mount point | |
685 | * labeling information. | |
686 | */ | |
e0007529 | 687 | static int selinux_set_mnt_opts(struct super_block *sb, |
649f6e77 DQ |
688 | struct security_mnt_opts *opts, |
689 | unsigned long kern_flags, | |
690 | unsigned long *set_kern_flags) | |
c9180a57 | 691 | { |
275bb41e | 692 | const struct cred *cred = current_cred(); |
c9180a57 | 693 | int rc = 0, i; |
c9180a57 | 694 | struct superblock_security_struct *sbsec = sb->s_security; |
29b1deb2 | 695 | const char *name = sb->s_type->name; |
83da53c5 | 696 | struct dentry *root = sbsec->sb->s_root; |
2c97165b | 697 | struct inode_security_struct *root_isec; |
c9180a57 EP |
698 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
699 | u32 defcontext_sid = 0; | |
e0007529 EP |
700 | char **mount_options = opts->mnt_opts; |
701 | int *flags = opts->mnt_opts_flags; | |
702 | int num_opts = opts->num_mnt_opts; | |
c9180a57 EP |
703 | |
704 | mutex_lock(&sbsec->lock); | |
705 | ||
706 | if (!ss_initialized) { | |
707 | if (!num_opts) { | |
708 | /* Defer initialization until selinux_complete_init, | |
709 | after the initial policy is loaded and the security | |
710 | server is ready to handle calls. */ | |
c9180a57 EP |
711 | goto out; |
712 | } | |
713 | rc = -EINVAL; | |
744ba35e EP |
714 | printk(KERN_WARNING "SELinux: Unable to set superblock options " |
715 | "before the security server is initialized\n"); | |
1da177e4 | 716 | goto out; |
c9180a57 | 717 | } |
649f6e77 DQ |
718 | if (kern_flags && !set_kern_flags) { |
719 | /* Specifying internal flags without providing a place to | |
720 | * place the results is not allowed */ | |
721 | rc = -EINVAL; | |
722 | goto out; | |
723 | } | |
1da177e4 | 724 | |
e0007529 EP |
725 | /* |
726 | * Binary mount data FS will come through this function twice. Once | |
727 | * from an explicit call and once from the generic calls from the vfs. | |
728 | * Since the generic VFS calls will not contain any security mount data | |
729 | * we need to skip the double mount verification. | |
730 | * | |
731 | * This does open a hole in which we will not notice if the first | |
732 | * mount using this sb set explict options and a second mount using | |
733 | * this sb does not set any security options. (The first options | |
734 | * will be used for both mounts) | |
735 | */ | |
0d90a7ec | 736 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
e0007529 | 737 | && (num_opts == 0)) |
f5269710 | 738 | goto out; |
e0007529 | 739 | |
2c97165b PM |
740 | root_isec = backing_inode_security_novalidate(root); |
741 | ||
c9180a57 EP |
742 | /* |
743 | * parse the mount options, check if they are valid sids. | |
744 | * also check if someone is trying to mount the same sb more | |
745 | * than once with different security options. | |
746 | */ | |
747 | for (i = 0; i < num_opts; i++) { | |
748 | u32 sid; | |
11689d47 | 749 | |
12f348b9 | 750 | if (flags[i] == SBLABEL_MNT) |
11689d47 | 751 | continue; |
44be2f65 | 752 | rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL); |
1da177e4 | 753 | if (rc) { |
44be2f65 | 754 | printk(KERN_WARNING "SELinux: security_context_str_to_sid" |
29b1deb2 LT |
755 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
756 | mount_options[i], sb->s_id, name, rc); | |
c9180a57 EP |
757 | goto out; |
758 | } | |
759 | switch (flags[i]) { | |
760 | case FSCONTEXT_MNT: | |
761 | fscontext_sid = sid; | |
762 | ||
763 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
764 | fscontext_sid)) | |
765 | goto out_double_mount; | |
766 | ||
767 | sbsec->flags |= FSCONTEXT_MNT; | |
768 | break; | |
769 | case CONTEXT_MNT: | |
770 | context_sid = sid; | |
771 | ||
772 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
773 | context_sid)) | |
774 | goto out_double_mount; | |
775 | ||
776 | sbsec->flags |= CONTEXT_MNT; | |
777 | break; | |
778 | case ROOTCONTEXT_MNT: | |
779 | rootcontext_sid = sid; | |
780 | ||
781 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
782 | rootcontext_sid)) | |
783 | goto out_double_mount; | |
784 | ||
785 | sbsec->flags |= ROOTCONTEXT_MNT; | |
786 | ||
787 | break; | |
788 | case DEFCONTEXT_MNT: | |
789 | defcontext_sid = sid; | |
790 | ||
791 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
792 | defcontext_sid)) | |
793 | goto out_double_mount; | |
794 | ||
795 | sbsec->flags |= DEFCONTEXT_MNT; | |
796 | ||
797 | break; | |
798 | default: | |
799 | rc = -EINVAL; | |
800 | goto out; | |
1da177e4 | 801 | } |
c9180a57 EP |
802 | } |
803 | ||
0d90a7ec | 804 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 805 | /* previously mounted with options, but not on this attempt? */ |
0d90a7ec | 806 | if ((sbsec->flags & SE_MNTMASK) && !num_opts) |
c9180a57 EP |
807 | goto out_double_mount; |
808 | rc = 0; | |
809 | goto out; | |
810 | } | |
811 | ||
089be43e | 812 | if (strcmp(sb->s_type->name, "proc") == 0) |
134509d5 SS |
813 | sbsec->flags |= SE_SBPROC | SE_SBGENFS; |
814 | ||
8e014720 SS |
815 | if (!strcmp(sb->s_type->name, "debugfs") || |
816 | !strcmp(sb->s_type->name, "sysfs") || | |
817 | !strcmp(sb->s_type->name, "pstore")) | |
134509d5 | 818 | sbsec->flags |= SE_SBGENFS; |
c9180a57 | 819 | |
eb9ae686 DQ |
820 | if (!sbsec->behavior) { |
821 | /* | |
822 | * Determine the labeling behavior to use for this | |
823 | * filesystem type. | |
824 | */ | |
98f700f3 | 825 | rc = security_fs_use(sb); |
eb9ae686 DQ |
826 | if (rc) { |
827 | printk(KERN_WARNING | |
828 | "%s: security_fs_use(%s) returned %d\n", | |
829 | __func__, sb->s_type->name, rc); | |
830 | goto out; | |
831 | } | |
c9180a57 | 832 | } |
c9180a57 EP |
833 | /* sets the context of the superblock for the fs being mounted. */ |
834 | if (fscontext_sid) { | |
275bb41e | 835 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
1da177e4 | 836 | if (rc) |
c9180a57 | 837 | goto out; |
1da177e4 | 838 | |
c9180a57 | 839 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
840 | } |
841 | ||
842 | /* | |
843 | * Switch to using mount point labeling behavior. | |
844 | * sets the label used on all file below the mountpoint, and will set | |
845 | * the superblock context if not already set. | |
846 | */ | |
eb9ae686 DQ |
847 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { |
848 | sbsec->behavior = SECURITY_FS_USE_NATIVE; | |
849 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
850 | } | |
851 | ||
c9180a57 EP |
852 | if (context_sid) { |
853 | if (!fscontext_sid) { | |
275bb41e DH |
854 | rc = may_context_mount_sb_relabel(context_sid, sbsec, |
855 | cred); | |
b04ea3ce | 856 | if (rc) |
c9180a57 EP |
857 | goto out; |
858 | sbsec->sid = context_sid; | |
b04ea3ce | 859 | } else { |
275bb41e DH |
860 | rc = may_context_mount_inode_relabel(context_sid, sbsec, |
861 | cred); | |
b04ea3ce | 862 | if (rc) |
c9180a57 | 863 | goto out; |
b04ea3ce | 864 | } |
c9180a57 EP |
865 | if (!rootcontext_sid) |
866 | rootcontext_sid = context_sid; | |
1da177e4 | 867 | |
c9180a57 | 868 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 869 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
870 | } |
871 | ||
c9180a57 | 872 | if (rootcontext_sid) { |
275bb41e DH |
873 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
874 | cred); | |
0808925e | 875 | if (rc) |
c9180a57 | 876 | goto out; |
0808925e | 877 | |
c9180a57 | 878 | root_isec->sid = rootcontext_sid; |
6f3be9f5 | 879 | root_isec->initialized = LABEL_INITIALIZED; |
0808925e EP |
880 | } |
881 | ||
c9180a57 | 882 | if (defcontext_sid) { |
eb9ae686 DQ |
883 | if (sbsec->behavior != SECURITY_FS_USE_XATTR && |
884 | sbsec->behavior != SECURITY_FS_USE_NATIVE) { | |
c9180a57 EP |
885 | rc = -EINVAL; |
886 | printk(KERN_WARNING "SELinux: defcontext option is " | |
887 | "invalid for this filesystem type\n"); | |
888 | goto out; | |
1da177e4 LT |
889 | } |
890 | ||
c9180a57 EP |
891 | if (defcontext_sid != sbsec->def_sid) { |
892 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
275bb41e | 893 | sbsec, cred); |
c9180a57 EP |
894 | if (rc) |
895 | goto out; | |
896 | } | |
1da177e4 | 897 | |
c9180a57 | 898 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
899 | } |
900 | ||
c9180a57 | 901 | rc = sb_finish_set_opts(sb); |
1da177e4 | 902 | out: |
c9180a57 | 903 | mutex_unlock(&sbsec->lock); |
1da177e4 | 904 | return rc; |
c9180a57 EP |
905 | out_double_mount: |
906 | rc = -EINVAL; | |
907 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " | |
29b1deb2 | 908 | "security settings for (dev %s, type %s)\n", sb->s_id, name); |
c9180a57 | 909 | goto out; |
1da177e4 LT |
910 | } |
911 | ||
094f7b69 JL |
912 | static int selinux_cmp_sb_context(const struct super_block *oldsb, |
913 | const struct super_block *newsb) | |
914 | { | |
915 | struct superblock_security_struct *old = oldsb->s_security; | |
916 | struct superblock_security_struct *new = newsb->s_security; | |
917 | char oldflags = old->flags & SE_MNTMASK; | |
918 | char newflags = new->flags & SE_MNTMASK; | |
919 | ||
920 | if (oldflags != newflags) | |
921 | goto mismatch; | |
922 | if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) | |
923 | goto mismatch; | |
924 | if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) | |
925 | goto mismatch; | |
926 | if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) | |
927 | goto mismatch; | |
928 | if (oldflags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
929 | struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); |
930 | struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); | |
094f7b69 JL |
931 | if (oldroot->sid != newroot->sid) |
932 | goto mismatch; | |
933 | } | |
934 | return 0; | |
935 | mismatch: | |
936 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " | |
937 | "different security settings for (dev %s, " | |
938 | "type %s)\n", newsb->s_id, newsb->s_type->name); | |
939 | return -EBUSY; | |
940 | } | |
941 | ||
942 | static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, | |
c9180a57 | 943 | struct super_block *newsb) |
1da177e4 | 944 | { |
c9180a57 EP |
945 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
946 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 947 | |
c9180a57 EP |
948 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
949 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
950 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 951 | |
0f5e6420 EP |
952 | /* |
953 | * if the parent was able to be mounted it clearly had no special lsm | |
e8c26255 | 954 | * mount options. thus we can safely deal with this superblock later |
0f5e6420 | 955 | */ |
e8c26255 | 956 | if (!ss_initialized) |
094f7b69 | 957 | return 0; |
c9180a57 | 958 | |
c9180a57 | 959 | /* how can we clone if the old one wasn't set up?? */ |
0d90a7ec | 960 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
c9180a57 | 961 | |
094f7b69 | 962 | /* if fs is reusing a sb, make sure that the contexts match */ |
0d90a7ec | 963 | if (newsbsec->flags & SE_SBINITIALIZED) |
094f7b69 | 964 | return selinux_cmp_sb_context(oldsb, newsb); |
5a552617 | 965 | |
c9180a57 EP |
966 | mutex_lock(&newsbsec->lock); |
967 | ||
968 | newsbsec->flags = oldsbsec->flags; | |
969 | ||
970 | newsbsec->sid = oldsbsec->sid; | |
971 | newsbsec->def_sid = oldsbsec->def_sid; | |
972 | newsbsec->behavior = oldsbsec->behavior; | |
973 | ||
974 | if (set_context) { | |
975 | u32 sid = oldsbsec->mntpoint_sid; | |
976 | ||
977 | if (!set_fscontext) | |
978 | newsbsec->sid = sid; | |
979 | if (!set_rootcontext) { | |
83da53c5 | 980 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); |
c9180a57 EP |
981 | newisec->sid = sid; |
982 | } | |
983 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 984 | } |
c9180a57 | 985 | if (set_rootcontext) { |
83da53c5 AG |
986 | const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); |
987 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); | |
1da177e4 | 988 | |
c9180a57 | 989 | newisec->sid = oldisec->sid; |
1da177e4 LT |
990 | } |
991 | ||
c9180a57 EP |
992 | sb_finish_set_opts(newsb); |
993 | mutex_unlock(&newsbsec->lock); | |
094f7b69 | 994 | return 0; |
c9180a57 EP |
995 | } |
996 | ||
2e1479d9 AB |
997 | static int selinux_parse_opts_str(char *options, |
998 | struct security_mnt_opts *opts) | |
c9180a57 | 999 | { |
e0007529 | 1000 | char *p; |
c9180a57 EP |
1001 | char *context = NULL, *defcontext = NULL; |
1002 | char *fscontext = NULL, *rootcontext = NULL; | |
e0007529 | 1003 | int rc, num_mnt_opts = 0; |
1da177e4 | 1004 | |
e0007529 | 1005 | opts->num_mnt_opts = 0; |
1da177e4 | 1006 | |
c9180a57 EP |
1007 | /* Standard string-based options. */ |
1008 | while ((p = strsep(&options, "|")) != NULL) { | |
1009 | int token; | |
1010 | substring_t args[MAX_OPT_ARGS]; | |
1da177e4 | 1011 | |
c9180a57 EP |
1012 | if (!*p) |
1013 | continue; | |
1da177e4 | 1014 | |
c9180a57 | 1015 | token = match_token(p, tokens, args); |
1da177e4 | 1016 | |
c9180a57 EP |
1017 | switch (token) { |
1018 | case Opt_context: | |
1019 | if (context || defcontext) { | |
1020 | rc = -EINVAL; | |
1021 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1022 | goto out_err; | |
1023 | } | |
1024 | context = match_strdup(&args[0]); | |
1025 | if (!context) { | |
1026 | rc = -ENOMEM; | |
1027 | goto out_err; | |
1028 | } | |
1029 | break; | |
1030 | ||
1031 | case Opt_fscontext: | |
1032 | if (fscontext) { | |
1033 | rc = -EINVAL; | |
1034 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1035 | goto out_err; | |
1036 | } | |
1037 | fscontext = match_strdup(&args[0]); | |
1038 | if (!fscontext) { | |
1039 | rc = -ENOMEM; | |
1040 | goto out_err; | |
1041 | } | |
1042 | break; | |
1043 | ||
1044 | case Opt_rootcontext: | |
1045 | if (rootcontext) { | |
1046 | rc = -EINVAL; | |
1047 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1048 | goto out_err; | |
1049 | } | |
1050 | rootcontext = match_strdup(&args[0]); | |
1051 | if (!rootcontext) { | |
1052 | rc = -ENOMEM; | |
1053 | goto out_err; | |
1054 | } | |
1055 | break; | |
1056 | ||
1057 | case Opt_defcontext: | |
1058 | if (context || defcontext) { | |
1059 | rc = -EINVAL; | |
1060 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1061 | goto out_err; | |
1062 | } | |
1063 | defcontext = match_strdup(&args[0]); | |
1064 | if (!defcontext) { | |
1065 | rc = -ENOMEM; | |
1066 | goto out_err; | |
1067 | } | |
1068 | break; | |
11689d47 DQ |
1069 | case Opt_labelsupport: |
1070 | break; | |
c9180a57 EP |
1071 | default: |
1072 | rc = -EINVAL; | |
1073 | printk(KERN_WARNING "SELinux: unknown mount option\n"); | |
1074 | goto out_err; | |
1da177e4 | 1075 | |
1da177e4 | 1076 | } |
1da177e4 | 1077 | } |
c9180a57 | 1078 | |
e0007529 EP |
1079 | rc = -ENOMEM; |
1080 | opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); | |
1081 | if (!opts->mnt_opts) | |
1082 | goto out_err; | |
1083 | ||
1084 | opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); | |
1085 | if (!opts->mnt_opts_flags) { | |
1086 | kfree(opts->mnt_opts); | |
1087 | goto out_err; | |
1088 | } | |
1089 | ||
c9180a57 | 1090 | if (fscontext) { |
e0007529 EP |
1091 | opts->mnt_opts[num_mnt_opts] = fscontext; |
1092 | opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; | |
c9180a57 EP |
1093 | } |
1094 | if (context) { | |
e0007529 EP |
1095 | opts->mnt_opts[num_mnt_opts] = context; |
1096 | opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; | |
c9180a57 EP |
1097 | } |
1098 | if (rootcontext) { | |
e0007529 EP |
1099 | opts->mnt_opts[num_mnt_opts] = rootcontext; |
1100 | opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; | |
c9180a57 EP |
1101 | } |
1102 | if (defcontext) { | |
e0007529 EP |
1103 | opts->mnt_opts[num_mnt_opts] = defcontext; |
1104 | opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
1105 | } |
1106 | ||
e0007529 EP |
1107 | opts->num_mnt_opts = num_mnt_opts; |
1108 | return 0; | |
1109 | ||
c9180a57 EP |
1110 | out_err: |
1111 | kfree(context); | |
1112 | kfree(defcontext); | |
1113 | kfree(fscontext); | |
1114 | kfree(rootcontext); | |
1da177e4 LT |
1115 | return rc; |
1116 | } | |
e0007529 EP |
1117 | /* |
1118 | * string mount options parsing and call set the sbsec | |
1119 | */ | |
1120 | static int superblock_doinit(struct super_block *sb, void *data) | |
1121 | { | |
1122 | int rc = 0; | |
1123 | char *options = data; | |
1124 | struct security_mnt_opts opts; | |
1125 | ||
1126 | security_init_mnt_opts(&opts); | |
1127 | ||
1128 | if (!data) | |
1129 | goto out; | |
1130 | ||
1131 | BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); | |
1132 | ||
1133 | rc = selinux_parse_opts_str(options, &opts); | |
1134 | if (rc) | |
1135 | goto out_err; | |
1136 | ||
1137 | out: | |
649f6e77 | 1138 | rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); |
e0007529 EP |
1139 | |
1140 | out_err: | |
1141 | security_free_mnt_opts(&opts); | |
1142 | return rc; | |
1143 | } | |
1da177e4 | 1144 | |
3583a711 AB |
1145 | static void selinux_write_opts(struct seq_file *m, |
1146 | struct security_mnt_opts *opts) | |
2069f457 EP |
1147 | { |
1148 | int i; | |
1149 | char *prefix; | |
1150 | ||
1151 | for (i = 0; i < opts->num_mnt_opts; i++) { | |
11689d47 DQ |
1152 | char *has_comma; |
1153 | ||
1154 | if (opts->mnt_opts[i]) | |
1155 | has_comma = strchr(opts->mnt_opts[i], ','); | |
1156 | else | |
1157 | has_comma = NULL; | |
2069f457 EP |
1158 | |
1159 | switch (opts->mnt_opts_flags[i]) { | |
1160 | case CONTEXT_MNT: | |
1161 | prefix = CONTEXT_STR; | |
1162 | break; | |
1163 | case FSCONTEXT_MNT: | |
1164 | prefix = FSCONTEXT_STR; | |
1165 | break; | |
1166 | case ROOTCONTEXT_MNT: | |
1167 | prefix = ROOTCONTEXT_STR; | |
1168 | break; | |
1169 | case DEFCONTEXT_MNT: | |
1170 | prefix = DEFCONTEXT_STR; | |
1171 | break; | |
12f348b9 | 1172 | case SBLABEL_MNT: |
11689d47 DQ |
1173 | seq_putc(m, ','); |
1174 | seq_puts(m, LABELSUPP_STR); | |
1175 | continue; | |
2069f457 EP |
1176 | default: |
1177 | BUG(); | |
a35c6c83 | 1178 | return; |
2069f457 EP |
1179 | }; |
1180 | /* we need a comma before each option */ | |
1181 | seq_putc(m, ','); | |
1182 | seq_puts(m, prefix); | |
1183 | if (has_comma) | |
1184 | seq_putc(m, '\"'); | |
a068acf2 | 1185 | seq_escape(m, opts->mnt_opts[i], "\"\n\\"); |
2069f457 EP |
1186 | if (has_comma) |
1187 | seq_putc(m, '\"'); | |
1188 | } | |
1189 | } | |
1190 | ||
1191 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1192 | { | |
1193 | struct security_mnt_opts opts; | |
1194 | int rc; | |
1195 | ||
1196 | rc = selinux_get_mnt_opts(sb, &opts); | |
383795c2 EP |
1197 | if (rc) { |
1198 | /* before policy load we may get EINVAL, don't show anything */ | |
1199 | if (rc == -EINVAL) | |
1200 | rc = 0; | |
2069f457 | 1201 | return rc; |
383795c2 | 1202 | } |
2069f457 EP |
1203 | |
1204 | selinux_write_opts(m, &opts); | |
1205 | ||
1206 | security_free_mnt_opts(&opts); | |
1207 | ||
1208 | return rc; | |
1209 | } | |
1210 | ||
1da177e4 LT |
1211 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1212 | { | |
1213 | switch (mode & S_IFMT) { | |
1214 | case S_IFSOCK: | |
1215 | return SECCLASS_SOCK_FILE; | |
1216 | case S_IFLNK: | |
1217 | return SECCLASS_LNK_FILE; | |
1218 | case S_IFREG: | |
1219 | return SECCLASS_FILE; | |
1220 | case S_IFBLK: | |
1221 | return SECCLASS_BLK_FILE; | |
1222 | case S_IFDIR: | |
1223 | return SECCLASS_DIR; | |
1224 | case S_IFCHR: | |
1225 | return SECCLASS_CHR_FILE; | |
1226 | case S_IFIFO: | |
1227 | return SECCLASS_FIFO_FILE; | |
1228 | ||
1229 | } | |
1230 | ||
1231 | return SECCLASS_FILE; | |
1232 | } | |
1233 | ||
13402580 JM |
1234 | static inline int default_protocol_stream(int protocol) |
1235 | { | |
1236 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1237 | } | |
1238 | ||
1239 | static inline int default_protocol_dgram(int protocol) | |
1240 | { | |
1241 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1242 | } | |
1243 | ||
1da177e4 LT |
1244 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1245 | { | |
1246 | switch (family) { | |
1247 | case PF_UNIX: | |
1248 | switch (type) { | |
1249 | case SOCK_STREAM: | |
1250 | case SOCK_SEQPACKET: | |
1251 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1252 | case SOCK_DGRAM: | |
1253 | return SECCLASS_UNIX_DGRAM_SOCKET; | |
1254 | } | |
1255 | break; | |
1256 | case PF_INET: | |
1257 | case PF_INET6: | |
1258 | switch (type) { | |
1259 | case SOCK_STREAM: | |
13402580 JM |
1260 | if (default_protocol_stream(protocol)) |
1261 | return SECCLASS_TCP_SOCKET; | |
1262 | else | |
1263 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1264 | case SOCK_DGRAM: |
13402580 JM |
1265 | if (default_protocol_dgram(protocol)) |
1266 | return SECCLASS_UDP_SOCKET; | |
1267 | else | |
1268 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1269 | case SOCK_DCCP: |
1270 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1271 | default: |
1da177e4 LT |
1272 | return SECCLASS_RAWIP_SOCKET; |
1273 | } | |
1274 | break; | |
1275 | case PF_NETLINK: | |
1276 | switch (protocol) { | |
1277 | case NETLINK_ROUTE: | |
1278 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
7f1fb60c | 1279 | case NETLINK_SOCK_DIAG: |
1da177e4 LT |
1280 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1281 | case NETLINK_NFLOG: | |
1282 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1283 | case NETLINK_XFRM: | |
1284 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1285 | case NETLINK_SELINUX: | |
1286 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
6c6d2e9b SS |
1287 | case NETLINK_ISCSI: |
1288 | return SECCLASS_NETLINK_ISCSI_SOCKET; | |
1da177e4 LT |
1289 | case NETLINK_AUDIT: |
1290 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
6c6d2e9b SS |
1291 | case NETLINK_FIB_LOOKUP: |
1292 | return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; | |
1293 | case NETLINK_CONNECTOR: | |
1294 | return SECCLASS_NETLINK_CONNECTOR_SOCKET; | |
1295 | case NETLINK_NETFILTER: | |
1296 | return SECCLASS_NETLINK_NETFILTER_SOCKET; | |
1da177e4 LT |
1297 | case NETLINK_DNRTMSG: |
1298 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1299 | case NETLINK_KOBJECT_UEVENT: |
1300 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
6c6d2e9b SS |
1301 | case NETLINK_GENERIC: |
1302 | return SECCLASS_NETLINK_GENERIC_SOCKET; | |
1303 | case NETLINK_SCSITRANSPORT: | |
1304 | return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; | |
1305 | case NETLINK_RDMA: | |
1306 | return SECCLASS_NETLINK_RDMA_SOCKET; | |
1307 | case NETLINK_CRYPTO: | |
1308 | return SECCLASS_NETLINK_CRYPTO_SOCKET; | |
1da177e4 LT |
1309 | default: |
1310 | return SECCLASS_NETLINK_SOCKET; | |
1311 | } | |
1312 | case PF_PACKET: | |
1313 | return SECCLASS_PACKET_SOCKET; | |
1314 | case PF_KEY: | |
1315 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1316 | case PF_APPLETALK: |
1317 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1318 | } |
1319 | ||
1320 | return SECCLASS_SOCKET; | |
1321 | } | |
1322 | ||
134509d5 SS |
1323 | static int selinux_genfs_get_sid(struct dentry *dentry, |
1324 | u16 tclass, | |
1325 | u16 flags, | |
1326 | u32 *sid) | |
1da177e4 | 1327 | { |
8e6c9693 | 1328 | int rc; |
fc64005c | 1329 | struct super_block *sb = dentry->d_sb; |
8e6c9693 | 1330 | char *buffer, *path; |
1da177e4 | 1331 | |
828dfe1d | 1332 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1333 | if (!buffer) |
1334 | return -ENOMEM; | |
1335 | ||
8e6c9693 LAG |
1336 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1337 | if (IS_ERR(path)) | |
1338 | rc = PTR_ERR(path); | |
1339 | else { | |
134509d5 SS |
1340 | if (flags & SE_SBPROC) { |
1341 | /* each process gets a /proc/PID/ entry. Strip off the | |
1342 | * PID part to get a valid selinux labeling. | |
1343 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1344 | while (path[1] >= '0' && path[1] <= '9') { | |
1345 | path[1] = '/'; | |
1346 | path++; | |
1347 | } | |
8e6c9693 | 1348 | } |
134509d5 | 1349 | rc = security_genfs_sid(sb->s_type->name, path, tclass, sid); |
1da177e4 | 1350 | } |
1da177e4 LT |
1351 | free_page((unsigned long)buffer); |
1352 | return rc; | |
1353 | } | |
1da177e4 LT |
1354 | |
1355 | /* The inode's security attributes must be initialized before first use. */ | |
1356 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1357 | { | |
1358 | struct superblock_security_struct *sbsec = NULL; | |
1359 | struct inode_security_struct *isec = inode->i_security; | |
1360 | u32 sid; | |
1361 | struct dentry *dentry; | |
1362 | #define INITCONTEXTLEN 255 | |
1363 | char *context = NULL; | |
1364 | unsigned len = 0; | |
1365 | int rc = 0; | |
1da177e4 | 1366 | |
6f3be9f5 | 1367 | if (isec->initialized == LABEL_INITIALIZED) |
1da177e4 LT |
1368 | goto out; |
1369 | ||
23970741 | 1370 | mutex_lock(&isec->lock); |
6f3be9f5 | 1371 | if (isec->initialized == LABEL_INITIALIZED) |
23970741 | 1372 | goto out_unlock; |
1da177e4 LT |
1373 | |
1374 | sbsec = inode->i_sb->s_security; | |
0d90a7ec | 1375 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1376 | /* Defer initialization until selinux_complete_init, |
1377 | after the initial policy is loaded and the security | |
1378 | server is ready to handle calls. */ | |
1379 | spin_lock(&sbsec->isec_lock); | |
1380 | if (list_empty(&isec->list)) | |
1381 | list_add(&isec->list, &sbsec->isec_head); | |
1382 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1383 | goto out_unlock; |
1da177e4 LT |
1384 | } |
1385 | ||
1386 | switch (sbsec->behavior) { | |
eb9ae686 DQ |
1387 | case SECURITY_FS_USE_NATIVE: |
1388 | break; | |
1da177e4 LT |
1389 | case SECURITY_FS_USE_XATTR: |
1390 | if (!inode->i_op->getxattr) { | |
1391 | isec->sid = sbsec->def_sid; | |
1392 | break; | |
1393 | } | |
1394 | ||
1395 | /* Need a dentry, since the xattr API requires one. | |
1396 | Life would be simpler if we could just pass the inode. */ | |
1397 | if (opt_dentry) { | |
1398 | /* Called from d_instantiate or d_splice_alias. */ | |
1399 | dentry = dget(opt_dentry); | |
1400 | } else { | |
1401 | /* Called from selinux_complete_init, try to find a dentry. */ | |
1402 | dentry = d_find_alias(inode); | |
1403 | } | |
1404 | if (!dentry) { | |
df7f54c0 EP |
1405 | /* |
1406 | * this is can be hit on boot when a file is accessed | |
1407 | * before the policy is loaded. When we load policy we | |
1408 | * may find inodes that have no dentry on the | |
1409 | * sbsec->isec_head list. No reason to complain as these | |
1410 | * will get fixed up the next time we go through | |
1411 | * inode_doinit with a dentry, before these inodes could | |
1412 | * be used again by userspace. | |
1413 | */ | |
23970741 | 1414 | goto out_unlock; |
1da177e4 LT |
1415 | } |
1416 | ||
1417 | len = INITCONTEXTLEN; | |
4cb912f1 | 1418 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1419 | if (!context) { |
1420 | rc = -ENOMEM; | |
1421 | dput(dentry); | |
23970741 | 1422 | goto out_unlock; |
1da177e4 | 1423 | } |
4cb912f1 | 1424 | context[len] = '\0'; |
ce23e640 | 1425 | rc = inode->i_op->getxattr(dentry, inode, XATTR_NAME_SELINUX, |
1da177e4 LT |
1426 | context, len); |
1427 | if (rc == -ERANGE) { | |
314dabb8 JM |
1428 | kfree(context); |
1429 | ||
1da177e4 | 1430 | /* Need a larger buffer. Query for the right size. */ |
ce23e640 | 1431 | rc = inode->i_op->getxattr(dentry, inode, XATTR_NAME_SELINUX, |
1da177e4 LT |
1432 | NULL, 0); |
1433 | if (rc < 0) { | |
1434 | dput(dentry); | |
23970741 | 1435 | goto out_unlock; |
1da177e4 | 1436 | } |
1da177e4 | 1437 | len = rc; |
4cb912f1 | 1438 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1439 | if (!context) { |
1440 | rc = -ENOMEM; | |
1441 | dput(dentry); | |
23970741 | 1442 | goto out_unlock; |
1da177e4 | 1443 | } |
4cb912f1 | 1444 | context[len] = '\0'; |
ce23e640 | 1445 | rc = inode->i_op->getxattr(dentry, inode, |
1da177e4 LT |
1446 | XATTR_NAME_SELINUX, |
1447 | context, len); | |
1448 | } | |
1449 | dput(dentry); | |
1450 | if (rc < 0) { | |
1451 | if (rc != -ENODATA) { | |
744ba35e | 1452 | printk(KERN_WARNING "SELinux: %s: getxattr returned " |
dd6f953a | 1453 | "%d for dev=%s ino=%ld\n", __func__, |
1da177e4 LT |
1454 | -rc, inode->i_sb->s_id, inode->i_ino); |
1455 | kfree(context); | |
23970741 | 1456 | goto out_unlock; |
1da177e4 LT |
1457 | } |
1458 | /* Map ENODATA to the default file SID */ | |
1459 | sid = sbsec->def_sid; | |
1460 | rc = 0; | |
1461 | } else { | |
f5c1d5b2 | 1462 | rc = security_context_to_sid_default(context, rc, &sid, |
869ab514 SS |
1463 | sbsec->def_sid, |
1464 | GFP_NOFS); | |
1da177e4 | 1465 | if (rc) { |
4ba0a8ad EP |
1466 | char *dev = inode->i_sb->s_id; |
1467 | unsigned long ino = inode->i_ino; | |
1468 | ||
1469 | if (rc == -EINVAL) { | |
1470 | if (printk_ratelimit()) | |
1471 | printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " | |
1472 | "context=%s. This indicates you may need to relabel the inode or the " | |
1473 | "filesystem in question.\n", ino, dev, context); | |
1474 | } else { | |
1475 | printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " | |
1476 | "returned %d for dev=%s ino=%ld\n", | |
1477 | __func__, context, -rc, dev, ino); | |
1478 | } | |
1da177e4 LT |
1479 | kfree(context); |
1480 | /* Leave with the unlabeled SID */ | |
1481 | rc = 0; | |
1482 | break; | |
1483 | } | |
1484 | } | |
1485 | kfree(context); | |
1486 | isec->sid = sid; | |
1487 | break; | |
1488 | case SECURITY_FS_USE_TASK: | |
1489 | isec->sid = isec->task_sid; | |
1490 | break; | |
1491 | case SECURITY_FS_USE_TRANS: | |
1492 | /* Default to the fs SID. */ | |
1493 | isec->sid = sbsec->sid; | |
1494 | ||
1495 | /* Try to obtain a transition SID. */ | |
1496 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
652bb9b0 EP |
1497 | rc = security_transition_sid(isec->task_sid, sbsec->sid, |
1498 | isec->sclass, NULL, &sid); | |
1da177e4 | 1499 | if (rc) |
23970741 | 1500 | goto out_unlock; |
1da177e4 LT |
1501 | isec->sid = sid; |
1502 | break; | |
c312feb2 EP |
1503 | case SECURITY_FS_USE_MNTPOINT: |
1504 | isec->sid = sbsec->mntpoint_sid; | |
1505 | break; | |
1da177e4 | 1506 | default: |
c312feb2 | 1507 | /* Default to the fs superblock SID. */ |
1da177e4 LT |
1508 | isec->sid = sbsec->sid; |
1509 | ||
134509d5 | 1510 | if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) { |
f64410ec PM |
1511 | /* We must have a dentry to determine the label on |
1512 | * procfs inodes */ | |
1513 | if (opt_dentry) | |
1514 | /* Called from d_instantiate or | |
1515 | * d_splice_alias. */ | |
1516 | dentry = dget(opt_dentry); | |
1517 | else | |
1518 | /* Called from selinux_complete_init, try to | |
1519 | * find a dentry. */ | |
1520 | dentry = d_find_alias(inode); | |
1521 | /* | |
1522 | * This can be hit on boot when a file is accessed | |
1523 | * before the policy is loaded. When we load policy we | |
1524 | * may find inodes that have no dentry on the | |
1525 | * sbsec->isec_head list. No reason to complain as | |
1526 | * these will get fixed up the next time we go through | |
1527 | * inode_doinit() with a dentry, before these inodes | |
1528 | * could be used again by userspace. | |
1529 | */ | |
1530 | if (!dentry) | |
1531 | goto out_unlock; | |
1532 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
134509d5 SS |
1533 | rc = selinux_genfs_get_sid(dentry, isec->sclass, |
1534 | sbsec->flags, &sid); | |
f64410ec PM |
1535 | dput(dentry); |
1536 | if (rc) | |
1537 | goto out_unlock; | |
1538 | isec->sid = sid; | |
1da177e4 LT |
1539 | } |
1540 | break; | |
1541 | } | |
1542 | ||
6f3be9f5 | 1543 | isec->initialized = LABEL_INITIALIZED; |
1da177e4 | 1544 | |
23970741 EP |
1545 | out_unlock: |
1546 | mutex_unlock(&isec->lock); | |
1da177e4 LT |
1547 | out: |
1548 | if (isec->sclass == SECCLASS_FILE) | |
1549 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1da177e4 LT |
1550 | return rc; |
1551 | } | |
1552 | ||
1553 | /* Convert a Linux signal to an access vector. */ | |
1554 | static inline u32 signal_to_av(int sig) | |
1555 | { | |
1556 | u32 perm = 0; | |
1557 | ||
1558 | switch (sig) { | |
1559 | case SIGCHLD: | |
1560 | /* Commonly granted from child to parent. */ | |
1561 | perm = PROCESS__SIGCHLD; | |
1562 | break; | |
1563 | case SIGKILL: | |
1564 | /* Cannot be caught or ignored */ | |
1565 | perm = PROCESS__SIGKILL; | |
1566 | break; | |
1567 | case SIGSTOP: | |
1568 | /* Cannot be caught or ignored */ | |
1569 | perm = PROCESS__SIGSTOP; | |
1570 | break; | |
1571 | default: | |
1572 | /* All other signals. */ | |
1573 | perm = PROCESS__SIGNAL; | |
1574 | break; | |
1575 | } | |
1576 | ||
1577 | return perm; | |
1578 | } | |
1579 | ||
d84f4f99 DH |
1580 | /* |
1581 | * Check permission between a pair of credentials | |
1582 | * fork check, ptrace check, etc. | |
1583 | */ | |
1584 | static int cred_has_perm(const struct cred *actor, | |
1585 | const struct cred *target, | |
1586 | u32 perms) | |
1587 | { | |
1588 | u32 asid = cred_sid(actor), tsid = cred_sid(target); | |
1589 | ||
1590 | return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); | |
1591 | } | |
1592 | ||
275bb41e | 1593 | /* |
88e67f3b | 1594 | * Check permission between a pair of tasks, e.g. signal checks, |
275bb41e DH |
1595 | * fork check, ptrace check, etc. |
1596 | * tsk1 is the actor and tsk2 is the target | |
3b11a1de | 1597 | * - this uses the default subjective creds of tsk1 |
275bb41e DH |
1598 | */ |
1599 | static int task_has_perm(const struct task_struct *tsk1, | |
1600 | const struct task_struct *tsk2, | |
1da177e4 LT |
1601 | u32 perms) |
1602 | { | |
275bb41e DH |
1603 | const struct task_security_struct *__tsec1, *__tsec2; |
1604 | u32 sid1, sid2; | |
1da177e4 | 1605 | |
275bb41e DH |
1606 | rcu_read_lock(); |
1607 | __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; | |
1608 | __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; | |
1609 | rcu_read_unlock(); | |
1610 | return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); | |
1da177e4 LT |
1611 | } |
1612 | ||
3b11a1de DH |
1613 | /* |
1614 | * Check permission between current and another task, e.g. signal checks, | |
1615 | * fork check, ptrace check, etc. | |
1616 | * current is the actor and tsk2 is the target | |
1617 | * - this uses current's subjective creds | |
1618 | */ | |
1619 | static int current_has_perm(const struct task_struct *tsk, | |
1620 | u32 perms) | |
1621 | { | |
1622 | u32 sid, tsid; | |
1623 | ||
1624 | sid = current_sid(); | |
1625 | tsid = task_sid(tsk); | |
1626 | return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); | |
1627 | } | |
1628 | ||
b68e418c SS |
1629 | #if CAP_LAST_CAP > 63 |
1630 | #error Fix SELinux to handle capabilities > 63. | |
1631 | #endif | |
1632 | ||
1da177e4 | 1633 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1634 | static int cred_has_capability(const struct cred *cred, |
8e4ff6f2 | 1635 | int cap, int audit, bool initns) |
1da177e4 | 1636 | { |
2bf49690 | 1637 | struct common_audit_data ad; |
06112163 | 1638 | struct av_decision avd; |
b68e418c | 1639 | u16 sclass; |
3699c53c | 1640 | u32 sid = cred_sid(cred); |
b68e418c | 1641 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1642 | int rc; |
1da177e4 | 1643 | |
50c205f5 | 1644 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1645 | ad.u.cap = cap; |
1646 | ||
b68e418c SS |
1647 | switch (CAP_TO_INDEX(cap)) { |
1648 | case 0: | |
8e4ff6f2 | 1649 | sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; |
b68e418c SS |
1650 | break; |
1651 | case 1: | |
8e4ff6f2 | 1652 | sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; |
b68e418c SS |
1653 | break; |
1654 | default: | |
1655 | printk(KERN_ERR | |
1656 | "SELinux: out of range capability %d\n", cap); | |
1657 | BUG(); | |
a35c6c83 | 1658 | return -EINVAL; |
b68e418c | 1659 | } |
06112163 | 1660 | |
275bb41e | 1661 | rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); |
9ade0cf4 | 1662 | if (audit == SECURITY_CAP_AUDIT) { |
7b20ea25 | 1663 | int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0); |
9ade0cf4 EP |
1664 | if (rc2) |
1665 | return rc2; | |
1666 | } | |
06112163 | 1667 | return rc; |
1da177e4 LT |
1668 | } |
1669 | ||
1670 | /* Check whether a task is allowed to use a system operation. */ | |
1671 | static int task_has_system(struct task_struct *tsk, | |
1672 | u32 perms) | |
1673 | { | |
275bb41e | 1674 | u32 sid = task_sid(tsk); |
1da177e4 | 1675 | |
275bb41e | 1676 | return avc_has_perm(sid, SECINITSID_KERNEL, |
1da177e4 LT |
1677 | SECCLASS_SYSTEM, perms, NULL); |
1678 | } | |
1679 | ||
1680 | /* Check whether a task has a particular permission to an inode. | |
1681 | The 'adp' parameter is optional and allows other audit | |
1682 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1683 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1684 | struct inode *inode, |
1685 | u32 perms, | |
19e49834 | 1686 | struct common_audit_data *adp) |
1da177e4 | 1687 | { |
1da177e4 | 1688 | struct inode_security_struct *isec; |
275bb41e | 1689 | u32 sid; |
1da177e4 | 1690 | |
e0e81739 DH |
1691 | validate_creds(cred); |
1692 | ||
828dfe1d | 1693 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1694 | return 0; |
1695 | ||
88e67f3b | 1696 | sid = cred_sid(cred); |
1da177e4 LT |
1697 | isec = inode->i_security; |
1698 | ||
19e49834 | 1699 | return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); |
1da177e4 LT |
1700 | } |
1701 | ||
1702 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1703 | the dentry to help the auditing code to more easily generate the | |
1704 | pathname if needed. */ | |
88e67f3b | 1705 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1706 | struct dentry *dentry, |
1707 | u32 av) | |
1708 | { | |
c6f493d6 | 1709 | struct inode *inode = d_backing_inode(dentry); |
2bf49690 | 1710 | struct common_audit_data ad; |
88e67f3b | 1711 | |
50c205f5 | 1712 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1713 | ad.u.dentry = dentry; |
5d226df4 | 1714 | __inode_security_revalidate(inode, dentry, true); |
19e49834 | 1715 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1716 | } |
1717 | ||
1718 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1719 | the path to help the auditing code to more easily generate the | |
1720 | pathname if needed. */ | |
1721 | static inline int path_has_perm(const struct cred *cred, | |
3f7036a0 | 1722 | const struct path *path, |
2875fa00 EP |
1723 | u32 av) |
1724 | { | |
c6f493d6 | 1725 | struct inode *inode = d_backing_inode(path->dentry); |
2875fa00 EP |
1726 | struct common_audit_data ad; |
1727 | ||
50c205f5 | 1728 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1729 | ad.u.path = *path; |
5d226df4 | 1730 | __inode_security_revalidate(inode, path->dentry, true); |
19e49834 | 1731 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1732 | } |
1733 | ||
13f8e981 DH |
1734 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1735 | static inline int file_path_has_perm(const struct cred *cred, | |
1736 | struct file *file, | |
1737 | u32 av) | |
1738 | { | |
1739 | struct common_audit_data ad; | |
1740 | ||
1741 | ad.type = LSM_AUDIT_DATA_PATH; | |
1742 | ad.u.path = file->f_path; | |
19e49834 | 1743 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1744 | } |
1745 | ||
1da177e4 LT |
1746 | /* Check whether a task can use an open file descriptor to |
1747 | access an inode in a given way. Check access to the | |
1748 | descriptor itself, and then use dentry_has_perm to | |
1749 | check a particular permission to the file. | |
1750 | Access to the descriptor is implicitly granted if it | |
1751 | has the same SID as the process. If av is zero, then | |
1752 | access to the file is not checked, e.g. for cases | |
1753 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1754 | static int file_has_perm(const struct cred *cred, |
1755 | struct file *file, | |
1756 | u32 av) | |
1da177e4 | 1757 | { |
1da177e4 | 1758 | struct file_security_struct *fsec = file->f_security; |
496ad9aa | 1759 | struct inode *inode = file_inode(file); |
2bf49690 | 1760 | struct common_audit_data ad; |
88e67f3b | 1761 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1762 | int rc; |
1763 | ||
50c205f5 | 1764 | ad.type = LSM_AUDIT_DATA_PATH; |
f48b7399 | 1765 | ad.u.path = file->f_path; |
1da177e4 | 1766 | |
275bb41e DH |
1767 | if (sid != fsec->sid) { |
1768 | rc = avc_has_perm(sid, fsec->sid, | |
1da177e4 LT |
1769 | SECCLASS_FD, |
1770 | FD__USE, | |
1771 | &ad); | |
1772 | if (rc) | |
88e67f3b | 1773 | goto out; |
1da177e4 LT |
1774 | } |
1775 | ||
1776 | /* av is zero if only checking access to the descriptor. */ | |
88e67f3b | 1777 | rc = 0; |
1da177e4 | 1778 | if (av) |
19e49834 | 1779 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1780 | |
88e67f3b DH |
1781 | out: |
1782 | return rc; | |
1da177e4 LT |
1783 | } |
1784 | ||
c3c188b2 DH |
1785 | /* |
1786 | * Determine the label for an inode that might be unioned. | |
1787 | */ | |
83da53c5 | 1788 | static int selinux_determine_inode_label(struct inode *dir, |
c3c188b2 DH |
1789 | const struct qstr *name, |
1790 | u16 tclass, | |
1791 | u32 *_new_isid) | |
1792 | { | |
1793 | const struct superblock_security_struct *sbsec = dir->i_sb->s_security; | |
c3c188b2 DH |
1794 | const struct task_security_struct *tsec = current_security(); |
1795 | ||
1796 | if ((sbsec->flags & SE_SBINITIALIZED) && | |
1797 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { | |
1798 | *_new_isid = sbsec->mntpoint_sid; | |
1799 | } else if ((sbsec->flags & SBLABEL_MNT) && | |
1800 | tsec->create_sid) { | |
1801 | *_new_isid = tsec->create_sid; | |
1802 | } else { | |
20cdef8d | 1803 | const struct inode_security_struct *dsec = inode_security(dir); |
c3c188b2 DH |
1804 | return security_transition_sid(tsec->sid, dsec->sid, tclass, |
1805 | name, _new_isid); | |
1806 | } | |
1807 | ||
1808 | return 0; | |
1809 | } | |
1810 | ||
1da177e4 LT |
1811 | /* Check whether a task can create a file. */ |
1812 | static int may_create(struct inode *dir, | |
1813 | struct dentry *dentry, | |
1814 | u16 tclass) | |
1815 | { | |
5fb49870 | 1816 | const struct task_security_struct *tsec = current_security(); |
1da177e4 LT |
1817 | struct inode_security_struct *dsec; |
1818 | struct superblock_security_struct *sbsec; | |
275bb41e | 1819 | u32 sid, newsid; |
2bf49690 | 1820 | struct common_audit_data ad; |
1da177e4 LT |
1821 | int rc; |
1822 | ||
83da53c5 | 1823 | dsec = inode_security(dir); |
1da177e4 LT |
1824 | sbsec = dir->i_sb->s_security; |
1825 | ||
275bb41e | 1826 | sid = tsec->sid; |
275bb41e | 1827 | |
50c205f5 | 1828 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1829 | ad.u.dentry = dentry; |
1da177e4 | 1830 | |
275bb41e | 1831 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
1832 | DIR__ADD_NAME | DIR__SEARCH, |
1833 | &ad); | |
1834 | if (rc) | |
1835 | return rc; | |
1836 | ||
c3c188b2 DH |
1837 | rc = selinux_determine_inode_label(dir, &dentry->d_name, tclass, |
1838 | &newsid); | |
1839 | if (rc) | |
1840 | return rc; | |
1da177e4 | 1841 | |
275bb41e | 1842 | rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); |
1da177e4 LT |
1843 | if (rc) |
1844 | return rc; | |
1845 | ||
1846 | return avc_has_perm(newsid, sbsec->sid, | |
1847 | SECCLASS_FILESYSTEM, | |
1848 | FILESYSTEM__ASSOCIATE, &ad); | |
1849 | } | |
1850 | ||
4eb582cf ML |
1851 | /* Check whether a task can create a key. */ |
1852 | static int may_create_key(u32 ksid, | |
1853 | struct task_struct *ctx) | |
1854 | { | |
275bb41e | 1855 | u32 sid = task_sid(ctx); |
4eb582cf | 1856 | |
275bb41e | 1857 | return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); |
4eb582cf ML |
1858 | } |
1859 | ||
828dfe1d EP |
1860 | #define MAY_LINK 0 |
1861 | #define MAY_UNLINK 1 | |
1862 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1863 | |
1864 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1865 | static int may_link(struct inode *dir, | |
1866 | struct dentry *dentry, | |
1867 | int kind) | |
1868 | ||
1869 | { | |
1da177e4 | 1870 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 1871 | struct common_audit_data ad; |
275bb41e | 1872 | u32 sid = current_sid(); |
1da177e4 LT |
1873 | u32 av; |
1874 | int rc; | |
1875 | ||
83da53c5 AG |
1876 | dsec = inode_security(dir); |
1877 | isec = backing_inode_security(dentry); | |
1da177e4 | 1878 | |
50c205f5 | 1879 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1880 | ad.u.dentry = dentry; |
1da177e4 LT |
1881 | |
1882 | av = DIR__SEARCH; | |
1883 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
275bb41e | 1884 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
1885 | if (rc) |
1886 | return rc; | |
1887 | ||
1888 | switch (kind) { | |
1889 | case MAY_LINK: | |
1890 | av = FILE__LINK; | |
1891 | break; | |
1892 | case MAY_UNLINK: | |
1893 | av = FILE__UNLINK; | |
1894 | break; | |
1895 | case MAY_RMDIR: | |
1896 | av = DIR__RMDIR; | |
1897 | break; | |
1898 | default: | |
744ba35e EP |
1899 | printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", |
1900 | __func__, kind); | |
1da177e4 LT |
1901 | return 0; |
1902 | } | |
1903 | ||
275bb41e | 1904 | rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); |
1da177e4 LT |
1905 | return rc; |
1906 | } | |
1907 | ||
1908 | static inline int may_rename(struct inode *old_dir, | |
1909 | struct dentry *old_dentry, | |
1910 | struct inode *new_dir, | |
1911 | struct dentry *new_dentry) | |
1912 | { | |
1da177e4 | 1913 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 1914 | struct common_audit_data ad; |
275bb41e | 1915 | u32 sid = current_sid(); |
1da177e4 LT |
1916 | u32 av; |
1917 | int old_is_dir, new_is_dir; | |
1918 | int rc; | |
1919 | ||
83da53c5 AG |
1920 | old_dsec = inode_security(old_dir); |
1921 | old_isec = backing_inode_security(old_dentry); | |
e36cb0b8 | 1922 | old_is_dir = d_is_dir(old_dentry); |
83da53c5 | 1923 | new_dsec = inode_security(new_dir); |
1da177e4 | 1924 | |
50c205f5 | 1925 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 1926 | |
a269434d | 1927 | ad.u.dentry = old_dentry; |
275bb41e | 1928 | rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
1929 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
1930 | if (rc) | |
1931 | return rc; | |
275bb41e | 1932 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
1933 | old_isec->sclass, FILE__RENAME, &ad); |
1934 | if (rc) | |
1935 | return rc; | |
1936 | if (old_is_dir && new_dir != old_dir) { | |
275bb41e | 1937 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
1938 | old_isec->sclass, DIR__REPARENT, &ad); |
1939 | if (rc) | |
1940 | return rc; | |
1941 | } | |
1942 | ||
a269434d | 1943 | ad.u.dentry = new_dentry; |
1da177e4 | 1944 | av = DIR__ADD_NAME | DIR__SEARCH; |
2c616d4d | 1945 | if (d_is_positive(new_dentry)) |
1da177e4 | 1946 | av |= DIR__REMOVE_NAME; |
275bb41e | 1947 | rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
1948 | if (rc) |
1949 | return rc; | |
2c616d4d | 1950 | if (d_is_positive(new_dentry)) { |
83da53c5 | 1951 | new_isec = backing_inode_security(new_dentry); |
e36cb0b8 | 1952 | new_is_dir = d_is_dir(new_dentry); |
275bb41e | 1953 | rc = avc_has_perm(sid, new_isec->sid, |
1da177e4 LT |
1954 | new_isec->sclass, |
1955 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1956 | if (rc) | |
1957 | return rc; | |
1958 | } | |
1959 | ||
1960 | return 0; | |
1961 | } | |
1962 | ||
1963 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 1964 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
1965 | struct super_block *sb, |
1966 | u32 perms, | |
2bf49690 | 1967 | struct common_audit_data *ad) |
1da177e4 | 1968 | { |
1da177e4 | 1969 | struct superblock_security_struct *sbsec; |
88e67f3b | 1970 | u32 sid = cred_sid(cred); |
1da177e4 | 1971 | |
1da177e4 | 1972 | sbsec = sb->s_security; |
275bb41e | 1973 | return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); |
1da177e4 LT |
1974 | } |
1975 | ||
1976 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1977 | static inline u32 file_mask_to_av(int mode, int mask) | |
1978 | { | |
1979 | u32 av = 0; | |
1980 | ||
dba19c60 | 1981 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
1982 | if (mask & MAY_EXEC) |
1983 | av |= FILE__EXECUTE; | |
1984 | if (mask & MAY_READ) | |
1985 | av |= FILE__READ; | |
1986 | ||
1987 | if (mask & MAY_APPEND) | |
1988 | av |= FILE__APPEND; | |
1989 | else if (mask & MAY_WRITE) | |
1990 | av |= FILE__WRITE; | |
1991 | ||
1992 | } else { | |
1993 | if (mask & MAY_EXEC) | |
1994 | av |= DIR__SEARCH; | |
1995 | if (mask & MAY_WRITE) | |
1996 | av |= DIR__WRITE; | |
1997 | if (mask & MAY_READ) | |
1998 | av |= DIR__READ; | |
1999 | } | |
2000 | ||
2001 | return av; | |
2002 | } | |
2003 | ||
8b6a5a37 EP |
2004 | /* Convert a Linux file to an access vector. */ |
2005 | static inline u32 file_to_av(struct file *file) | |
2006 | { | |
2007 | u32 av = 0; | |
2008 | ||
2009 | if (file->f_mode & FMODE_READ) | |
2010 | av |= FILE__READ; | |
2011 | if (file->f_mode & FMODE_WRITE) { | |
2012 | if (file->f_flags & O_APPEND) | |
2013 | av |= FILE__APPEND; | |
2014 | else | |
2015 | av |= FILE__WRITE; | |
2016 | } | |
2017 | if (!av) { | |
2018 | /* | |
2019 | * Special file opened with flags 3 for ioctl-only use. | |
2020 | */ | |
2021 | av = FILE__IOCTL; | |
2022 | } | |
2023 | ||
2024 | return av; | |
2025 | } | |
2026 | ||
b0c636b9 | 2027 | /* |
8b6a5a37 | 2028 | * Convert a file to an access vector and include the correct open |
b0c636b9 EP |
2029 | * open permission. |
2030 | */ | |
8b6a5a37 | 2031 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 2032 | { |
8b6a5a37 | 2033 | u32 av = file_to_av(file); |
b0c636b9 | 2034 | |
49b7b8de EP |
2035 | if (selinux_policycap_openperm) |
2036 | av |= FILE__OPEN; | |
2037 | ||
b0c636b9 EP |
2038 | return av; |
2039 | } | |
2040 | ||
1da177e4 LT |
2041 | /* Hook functions begin here. */ |
2042 | ||
79af7307 SS |
2043 | static int selinux_binder_set_context_mgr(struct task_struct *mgr) |
2044 | { | |
2045 | u32 mysid = current_sid(); | |
2046 | u32 mgrsid = task_sid(mgr); | |
2047 | ||
2048 | return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER, | |
2049 | BINDER__SET_CONTEXT_MGR, NULL); | |
2050 | } | |
2051 | ||
2052 | static int selinux_binder_transaction(struct task_struct *from, | |
2053 | struct task_struct *to) | |
2054 | { | |
2055 | u32 mysid = current_sid(); | |
2056 | u32 fromsid = task_sid(from); | |
2057 | u32 tosid = task_sid(to); | |
2058 | int rc; | |
2059 | ||
2060 | if (mysid != fromsid) { | |
2061 | rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, | |
2062 | BINDER__IMPERSONATE, NULL); | |
2063 | if (rc) | |
2064 | return rc; | |
2065 | } | |
2066 | ||
2067 | return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, | |
2068 | NULL); | |
2069 | } | |
2070 | ||
2071 | static int selinux_binder_transfer_binder(struct task_struct *from, | |
2072 | struct task_struct *to) | |
2073 | { | |
2074 | u32 fromsid = task_sid(from); | |
2075 | u32 tosid = task_sid(to); | |
2076 | ||
2077 | return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, | |
2078 | NULL); | |
2079 | } | |
2080 | ||
2081 | static int selinux_binder_transfer_file(struct task_struct *from, | |
2082 | struct task_struct *to, | |
2083 | struct file *file) | |
2084 | { | |
2085 | u32 sid = task_sid(to); | |
2086 | struct file_security_struct *fsec = file->f_security; | |
83da53c5 | 2087 | struct dentry *dentry = file->f_path.dentry; |
20cdef8d | 2088 | struct inode_security_struct *isec; |
79af7307 SS |
2089 | struct common_audit_data ad; |
2090 | int rc; | |
2091 | ||
2092 | ad.type = LSM_AUDIT_DATA_PATH; | |
2093 | ad.u.path = file->f_path; | |
2094 | ||
2095 | if (sid != fsec->sid) { | |
2096 | rc = avc_has_perm(sid, fsec->sid, | |
2097 | SECCLASS_FD, | |
2098 | FD__USE, | |
2099 | &ad); | |
2100 | if (rc) | |
2101 | return rc; | |
2102 | } | |
2103 | ||
83da53c5 | 2104 | if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
79af7307 SS |
2105 | return 0; |
2106 | ||
20cdef8d | 2107 | isec = backing_inode_security(dentry); |
79af7307 SS |
2108 | return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), |
2109 | &ad); | |
2110 | } | |
2111 | ||
9e48858f | 2112 | static int selinux_ptrace_access_check(struct task_struct *child, |
5cd9c58f | 2113 | unsigned int mode) |
1da177e4 | 2114 | { |
69f594a3 | 2115 | if (mode & PTRACE_MODE_READ) { |
275bb41e DH |
2116 | u32 sid = current_sid(); |
2117 | u32 csid = task_sid(child); | |
2118 | return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 SS |
2119 | } |
2120 | ||
3b11a1de | 2121 | return current_has_perm(child, PROCESS__PTRACE); |
5cd9c58f DH |
2122 | } |
2123 | ||
2124 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
2125 | { | |
5cd9c58f | 2126 | return task_has_perm(parent, current, PROCESS__PTRACE); |
1da177e4 LT |
2127 | } |
2128 | ||
2129 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 2130 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 | 2131 | { |
b1d9e6b0 | 2132 | return current_has_perm(target, PROCESS__GETCAP); |
1da177e4 LT |
2133 | } |
2134 | ||
d84f4f99 DH |
2135 | static int selinux_capset(struct cred *new, const struct cred *old, |
2136 | const kernel_cap_t *effective, | |
2137 | const kernel_cap_t *inheritable, | |
2138 | const kernel_cap_t *permitted) | |
1da177e4 | 2139 | { |
d84f4f99 | 2140 | return cred_has_perm(old, new, PROCESS__SETCAP); |
1da177e4 LT |
2141 | } |
2142 | ||
5626d3e8 JM |
2143 | /* |
2144 | * (This comment used to live with the selinux_task_setuid hook, | |
2145 | * which was removed). | |
2146 | * | |
2147 | * Since setuid only affects the current process, and since the SELinux | |
2148 | * controls are not based on the Linux identity attributes, SELinux does not | |
2149 | * need to control this operation. However, SELinux does control the use of | |
2150 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
2151 | */ | |
2152 | ||
6a9de491 EP |
2153 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
2154 | int cap, int audit) | |
1da177e4 | 2155 | { |
8e4ff6f2 | 2156 | return cred_has_capability(cred, cap, audit, ns == &init_user_ns); |
1da177e4 LT |
2157 | } |
2158 | ||
1da177e4 LT |
2159 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
2160 | { | |
88e67f3b | 2161 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2162 | int rc = 0; |
2163 | ||
2164 | if (!sb) | |
2165 | return 0; | |
2166 | ||
2167 | switch (cmds) { | |
828dfe1d EP |
2168 | case Q_SYNC: |
2169 | case Q_QUOTAON: | |
2170 | case Q_QUOTAOFF: | |
2171 | case Q_SETINFO: | |
2172 | case Q_SETQUOTA: | |
88e67f3b | 2173 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
2174 | break; |
2175 | case Q_GETFMT: | |
2176 | case Q_GETINFO: | |
2177 | case Q_GETQUOTA: | |
88e67f3b | 2178 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
2179 | break; |
2180 | default: | |
2181 | rc = 0; /* let the kernel handle invalid cmds */ | |
2182 | break; | |
1da177e4 LT |
2183 | } |
2184 | return rc; | |
2185 | } | |
2186 | ||
2187 | static int selinux_quota_on(struct dentry *dentry) | |
2188 | { | |
88e67f3b DH |
2189 | const struct cred *cred = current_cred(); |
2190 | ||
2875fa00 | 2191 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
2192 | } |
2193 | ||
12b3052c | 2194 | static int selinux_syslog(int type) |
1da177e4 LT |
2195 | { |
2196 | int rc; | |
2197 | ||
1da177e4 | 2198 | switch (type) { |
d78ca3cd KC |
2199 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2200 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
828dfe1d EP |
2201 | rc = task_has_system(current, SYSTEM__SYSLOG_READ); |
2202 | break; | |
d78ca3cd KC |
2203 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2204 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2205 | /* Set level of messages printed to console */ | |
2206 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
828dfe1d EP |
2207 | rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); |
2208 | break; | |
d78ca3cd KC |
2209 | case SYSLOG_ACTION_CLOSE: /* Close log */ |
2210 | case SYSLOG_ACTION_OPEN: /* Open log */ | |
2211 | case SYSLOG_ACTION_READ: /* Read from log */ | |
2212 | case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ | |
2213 | case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ | |
828dfe1d EP |
2214 | default: |
2215 | rc = task_has_system(current, SYSTEM__SYSLOG_MOD); | |
2216 | break; | |
1da177e4 LT |
2217 | } |
2218 | return rc; | |
2219 | } | |
2220 | ||
2221 | /* | |
2222 | * Check that a process has enough memory to allocate a new virtual | |
2223 | * mapping. 0 means there is enough memory for the allocation to | |
2224 | * succeed and -ENOMEM implies there is not. | |
2225 | * | |
1da177e4 LT |
2226 | * Do not audit the selinux permission check, as this is applied to all |
2227 | * processes that allocate mappings. | |
2228 | */ | |
34b4e4aa | 2229 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2230 | { |
2231 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2232 | |
b1d9e6b0 | 2233 | rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, |
8e4ff6f2 | 2234 | SECURITY_CAP_NOAUDIT, true); |
1da177e4 LT |
2235 | if (rc == 0) |
2236 | cap_sys_admin = 1; | |
2237 | ||
b1d9e6b0 | 2238 | return cap_sys_admin; |
1da177e4 LT |
2239 | } |
2240 | ||
2241 | /* binprm security operations */ | |
2242 | ||
0c6181cb PM |
2243 | static u32 ptrace_parent_sid(struct task_struct *task) |
2244 | { | |
2245 | u32 sid = 0; | |
2246 | struct task_struct *tracer; | |
2247 | ||
2248 | rcu_read_lock(); | |
2249 | tracer = ptrace_parent(task); | |
2250 | if (tracer) | |
2251 | sid = task_sid(tracer); | |
2252 | rcu_read_unlock(); | |
2253 | ||
2254 | return sid; | |
2255 | } | |
2256 | ||
7b0d0b40 SS |
2257 | static int check_nnp_nosuid(const struct linux_binprm *bprm, |
2258 | const struct task_security_struct *old_tsec, | |
2259 | const struct task_security_struct *new_tsec) | |
2260 | { | |
2261 | int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); | |
2262 | int nosuid = (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID); | |
2263 | int rc; | |
2264 | ||
2265 | if (!nnp && !nosuid) | |
2266 | return 0; /* neither NNP nor nosuid */ | |
2267 | ||
2268 | if (new_tsec->sid == old_tsec->sid) | |
2269 | return 0; /* No change in credentials */ | |
2270 | ||
2271 | /* | |
2272 | * The only transitions we permit under NNP or nosuid | |
2273 | * are transitions to bounded SIDs, i.e. SIDs that are | |
2274 | * guaranteed to only be allowed a subset of the permissions | |
2275 | * of the current SID. | |
2276 | */ | |
2277 | rc = security_bounded_transition(old_tsec->sid, new_tsec->sid); | |
2278 | if (rc) { | |
2279 | /* | |
2280 | * On failure, preserve the errno values for NNP vs nosuid. | |
2281 | * NNP: Operation not permitted for caller. | |
2282 | * nosuid: Permission denied to file. | |
2283 | */ | |
2284 | if (nnp) | |
2285 | return -EPERM; | |
2286 | else | |
2287 | return -EACCES; | |
2288 | } | |
2289 | return 0; | |
2290 | } | |
2291 | ||
a6f76f23 | 2292 | static int selinux_bprm_set_creds(struct linux_binprm *bprm) |
1da177e4 | 2293 | { |
a6f76f23 DH |
2294 | const struct task_security_struct *old_tsec; |
2295 | struct task_security_struct *new_tsec; | |
1da177e4 | 2296 | struct inode_security_struct *isec; |
2bf49690 | 2297 | struct common_audit_data ad; |
496ad9aa | 2298 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2299 | int rc; |
2300 | ||
a6f76f23 DH |
2301 | /* SELinux context only depends on initial program or script and not |
2302 | * the script interpreter */ | |
2303 | if (bprm->cred_prepared) | |
1da177e4 LT |
2304 | return 0; |
2305 | ||
a6f76f23 DH |
2306 | old_tsec = current_security(); |
2307 | new_tsec = bprm->cred->security; | |
83da53c5 | 2308 | isec = inode_security(inode); |
1da177e4 LT |
2309 | |
2310 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2311 | new_tsec->sid = old_tsec->sid; |
2312 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2313 | |
28eba5bf | 2314 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2315 | new_tsec->create_sid = 0; |
2316 | new_tsec->keycreate_sid = 0; | |
2317 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2318 | |
a6f76f23 DH |
2319 | if (old_tsec->exec_sid) { |
2320 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2321 | /* Reset exec SID on execve. */ |
a6f76f23 | 2322 | new_tsec->exec_sid = 0; |
259e5e6c | 2323 | |
7b0d0b40 SS |
2324 | /* Fail on NNP or nosuid if not an allowed transition. */ |
2325 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2326 | if (rc) | |
2327 | return rc; | |
1da177e4 LT |
2328 | } else { |
2329 | /* Check for a default transition on this program. */ | |
a6f76f23 | 2330 | rc = security_transition_sid(old_tsec->sid, isec->sid, |
652bb9b0 EP |
2331 | SECCLASS_PROCESS, NULL, |
2332 | &new_tsec->sid); | |
1da177e4 LT |
2333 | if (rc) |
2334 | return rc; | |
7b0d0b40 SS |
2335 | |
2336 | /* | |
2337 | * Fallback to old SID on NNP or nosuid if not an allowed | |
2338 | * transition. | |
2339 | */ | |
2340 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2341 | if (rc) | |
2342 | new_tsec->sid = old_tsec->sid; | |
1da177e4 LT |
2343 | } |
2344 | ||
50c205f5 | 2345 | ad.type = LSM_AUDIT_DATA_PATH; |
f48b7399 | 2346 | ad.u.path = bprm->file->f_path; |
1da177e4 | 2347 | |
a6f76f23 DH |
2348 | if (new_tsec->sid == old_tsec->sid) { |
2349 | rc = avc_has_perm(old_tsec->sid, isec->sid, | |
1da177e4 LT |
2350 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2351 | if (rc) | |
2352 | return rc; | |
2353 | } else { | |
2354 | /* Check permissions for the transition. */ | |
a6f76f23 | 2355 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
1da177e4 LT |
2356 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2357 | if (rc) | |
2358 | return rc; | |
2359 | ||
a6f76f23 | 2360 | rc = avc_has_perm(new_tsec->sid, isec->sid, |
1da177e4 LT |
2361 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2362 | if (rc) | |
2363 | return rc; | |
2364 | ||
a6f76f23 DH |
2365 | /* Check for shared state */ |
2366 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
2367 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, | |
2368 | SECCLASS_PROCESS, PROCESS__SHARE, | |
2369 | NULL); | |
2370 | if (rc) | |
2371 | return -EPERM; | |
2372 | } | |
2373 | ||
2374 | /* Make sure that anyone attempting to ptrace over a task that | |
2375 | * changes its SID has the appropriate permit */ | |
2376 | if (bprm->unsafe & | |
2377 | (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { | |
0c6181cb | 2378 | u32 ptsid = ptrace_parent_sid(current); |
a6f76f23 DH |
2379 | if (ptsid != 0) { |
2380 | rc = avc_has_perm(ptsid, new_tsec->sid, | |
2381 | SECCLASS_PROCESS, | |
2382 | PROCESS__PTRACE, NULL); | |
2383 | if (rc) | |
2384 | return -EPERM; | |
2385 | } | |
2386 | } | |
1da177e4 | 2387 | |
a6f76f23 DH |
2388 | /* Clear any possibly unsafe personality bits on exec: */ |
2389 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
1da177e4 LT |
2390 | } |
2391 | ||
1da177e4 LT |
2392 | return 0; |
2393 | } | |
2394 | ||
828dfe1d | 2395 | static int selinux_bprm_secureexec(struct linux_binprm *bprm) |
1da177e4 | 2396 | { |
5fb49870 | 2397 | const struct task_security_struct *tsec = current_security(); |
275bb41e | 2398 | u32 sid, osid; |
1da177e4 LT |
2399 | int atsecure = 0; |
2400 | ||
275bb41e DH |
2401 | sid = tsec->sid; |
2402 | osid = tsec->osid; | |
2403 | ||
2404 | if (osid != sid) { | |
1da177e4 LT |
2405 | /* Enable secure mode for SIDs transitions unless |
2406 | the noatsecure permission is granted between | |
2407 | the two SIDs, i.e. ahp returns 0. */ | |
275bb41e | 2408 | atsecure = avc_has_perm(osid, sid, |
a6f76f23 DH |
2409 | SECCLASS_PROCESS, |
2410 | PROCESS__NOATSECURE, NULL); | |
1da177e4 LT |
2411 | } |
2412 | ||
b1d9e6b0 | 2413 | return !!atsecure; |
1da177e4 LT |
2414 | } |
2415 | ||
c3c073f8 AV |
2416 | static int match_file(const void *p, struct file *file, unsigned fd) |
2417 | { | |
2418 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2419 | } | |
2420 | ||
1da177e4 | 2421 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2422 | static inline void flush_unauthorized_files(const struct cred *cred, |
2423 | struct files_struct *files) | |
1da177e4 | 2424 | { |
1da177e4 | 2425 | struct file *file, *devnull = NULL; |
b20c8122 | 2426 | struct tty_struct *tty; |
24ec839c | 2427 | int drop_tty = 0; |
c3c073f8 | 2428 | unsigned n; |
1da177e4 | 2429 | |
24ec839c | 2430 | tty = get_current_tty(); |
1da177e4 | 2431 | if (tty) { |
4a510969 | 2432 | spin_lock(&tty->files_lock); |
37dd0bd0 | 2433 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2434 | struct tty_file_private *file_priv; |
37dd0bd0 | 2435 | |
1da177e4 | 2436 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2437 | Use file_path_has_perm on the tty path directly |
2438 | rather than using file_has_perm, as this particular | |
2439 | open file may belong to another process and we are | |
2440 | only interested in the inode-based check here. */ | |
d996b62a NP |
2441 | file_priv = list_first_entry(&tty->tty_files, |
2442 | struct tty_file_private, list); | |
2443 | file = file_priv->file; | |
13f8e981 | 2444 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2445 | drop_tty = 1; |
1da177e4 | 2446 | } |
4a510969 | 2447 | spin_unlock(&tty->files_lock); |
452a00d2 | 2448 | tty_kref_put(tty); |
1da177e4 | 2449 | } |
98a27ba4 EB |
2450 | /* Reset controlling tty. */ |
2451 | if (drop_tty) | |
2452 | no_tty(); | |
1da177e4 LT |
2453 | |
2454 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2455 | n = iterate_fd(files, 0, match_file, cred); |
2456 | if (!n) /* none found? */ | |
2457 | return; | |
1da177e4 | 2458 | |
c3c073f8 | 2459 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2460 | if (IS_ERR(devnull)) |
2461 | devnull = NULL; | |
2462 | /* replace all the matching ones with this */ | |
2463 | do { | |
2464 | replace_fd(n - 1, devnull, 0); | |
2465 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2466 | if (devnull) | |
c3c073f8 | 2467 | fput(devnull); |
1da177e4 LT |
2468 | } |
2469 | ||
a6f76f23 DH |
2470 | /* |
2471 | * Prepare a process for imminent new credential changes due to exec | |
2472 | */ | |
2473 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2474 | { |
a6f76f23 DH |
2475 | struct task_security_struct *new_tsec; |
2476 | struct rlimit *rlim, *initrlim; | |
2477 | int rc, i; | |
d84f4f99 | 2478 | |
a6f76f23 DH |
2479 | new_tsec = bprm->cred->security; |
2480 | if (new_tsec->sid == new_tsec->osid) | |
2481 | return; | |
1da177e4 | 2482 | |
a6f76f23 DH |
2483 | /* Close files for which the new task SID is not authorized. */ |
2484 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2485 | |
a6f76f23 DH |
2486 | /* Always clear parent death signal on SID transitions. */ |
2487 | current->pdeath_signal = 0; | |
0356357c | 2488 | |
a6f76f23 DH |
2489 | /* Check whether the new SID can inherit resource limits from the old |
2490 | * SID. If not, reset all soft limits to the lower of the current | |
2491 | * task's hard limit and the init task's soft limit. | |
2492 | * | |
2493 | * Note that the setting of hard limits (even to lower them) can be | |
2494 | * controlled by the setrlimit check. The inclusion of the init task's | |
2495 | * soft limit into the computation is to avoid resetting soft limits | |
2496 | * higher than the default soft limit for cases where the default is | |
2497 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2498 | */ | |
2499 | rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
2500 | PROCESS__RLIMITINH, NULL); | |
2501 | if (rc) { | |
eb2d55a3 ON |
2502 | /* protect against do_prlimit() */ |
2503 | task_lock(current); | |
a6f76f23 DH |
2504 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2505 | rlim = current->signal->rlim + i; | |
2506 | initrlim = init_task.signal->rlim + i; | |
2507 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2508 | } |
eb2d55a3 ON |
2509 | task_unlock(current); |
2510 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2511 | } |
2512 | } | |
2513 | ||
2514 | /* | |
a6f76f23 DH |
2515 | * Clean up the process immediately after the installation of new credentials |
2516 | * due to exec | |
1da177e4 | 2517 | */ |
a6f76f23 | 2518 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2519 | { |
a6f76f23 | 2520 | const struct task_security_struct *tsec = current_security(); |
1da177e4 | 2521 | struct itimerval itimer; |
a6f76f23 | 2522 | u32 osid, sid; |
1da177e4 LT |
2523 | int rc, i; |
2524 | ||
a6f76f23 DH |
2525 | osid = tsec->osid; |
2526 | sid = tsec->sid; | |
2527 | ||
2528 | if (sid == osid) | |
1da177e4 LT |
2529 | return; |
2530 | ||
a6f76f23 DH |
2531 | /* Check whether the new SID can inherit signal state from the old SID. |
2532 | * If not, clear itimers to avoid subsequent signal generation and | |
2533 | * flush and unblock signals. | |
2534 | * | |
2535 | * This must occur _after_ the task SID has been updated so that any | |
2536 | * kill done after the flush will be checked against the new SID. | |
2537 | */ | |
2538 | rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 LT |
2539 | if (rc) { |
2540 | memset(&itimer, 0, sizeof itimer); | |
2541 | for (i = 0; i < 3; i++) | |
2542 | do_setitimer(i, &itimer, NULL); | |
1da177e4 | 2543 | spin_lock_irq(¤t->sighand->siglock); |
9e7c8f8c ON |
2544 | if (!fatal_signal_pending(current)) { |
2545 | flush_sigqueue(¤t->pending); | |
2546 | flush_sigqueue(¤t->signal->shared_pending); | |
3bcac026 DH |
2547 | flush_signal_handlers(current, 1); |
2548 | sigemptyset(¤t->blocked); | |
9e7c8f8c | 2549 | recalc_sigpending(); |
3bcac026 | 2550 | } |
1da177e4 LT |
2551 | spin_unlock_irq(¤t->sighand->siglock); |
2552 | } | |
2553 | ||
a6f76f23 DH |
2554 | /* Wake up the parent if it is waiting so that it can recheck |
2555 | * wait permission to the new task SID. */ | |
ecd6de3c | 2556 | read_lock(&tasklist_lock); |
0b7570e7 | 2557 | __wake_up_parent(current, current->real_parent); |
ecd6de3c | 2558 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2559 | } |
2560 | ||
2561 | /* superblock security operations */ | |
2562 | ||
2563 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2564 | { | |
2565 | return superblock_alloc_security(sb); | |
2566 | } | |
2567 | ||
2568 | static void selinux_sb_free_security(struct super_block *sb) | |
2569 | { | |
2570 | superblock_free_security(sb); | |
2571 | } | |
2572 | ||
2573 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2574 | { | |
2575 | if (plen > olen) | |
2576 | return 0; | |
2577 | ||
2578 | return !memcmp(prefix, option, plen); | |
2579 | } | |
2580 | ||
2581 | static inline int selinux_option(char *option, int len) | |
2582 | { | |
832cbd9a EP |
2583 | return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || |
2584 | match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || | |
2585 | match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || | |
11689d47 DQ |
2586 | match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || |
2587 | match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); | |
1da177e4 LT |
2588 | } |
2589 | ||
2590 | static inline void take_option(char **to, char *from, int *first, int len) | |
2591 | { | |
2592 | if (!*first) { | |
2593 | **to = ','; | |
2594 | *to += 1; | |
3528a953 | 2595 | } else |
1da177e4 LT |
2596 | *first = 0; |
2597 | memcpy(*to, from, len); | |
2598 | *to += len; | |
2599 | } | |
2600 | ||
828dfe1d EP |
2601 | static inline void take_selinux_option(char **to, char *from, int *first, |
2602 | int len) | |
3528a953 CO |
2603 | { |
2604 | int current_size = 0; | |
2605 | ||
2606 | if (!*first) { | |
2607 | **to = '|'; | |
2608 | *to += 1; | |
828dfe1d | 2609 | } else |
3528a953 CO |
2610 | *first = 0; |
2611 | ||
2612 | while (current_size < len) { | |
2613 | if (*from != '"') { | |
2614 | **to = *from; | |
2615 | *to += 1; | |
2616 | } | |
2617 | from += 1; | |
2618 | current_size += 1; | |
2619 | } | |
2620 | } | |
2621 | ||
e0007529 | 2622 | static int selinux_sb_copy_data(char *orig, char *copy) |
1da177e4 LT |
2623 | { |
2624 | int fnosec, fsec, rc = 0; | |
2625 | char *in_save, *in_curr, *in_end; | |
2626 | char *sec_curr, *nosec_save, *nosec; | |
3528a953 | 2627 | int open_quote = 0; |
1da177e4 LT |
2628 | |
2629 | in_curr = orig; | |
2630 | sec_curr = copy; | |
2631 | ||
1da177e4 LT |
2632 | nosec = (char *)get_zeroed_page(GFP_KERNEL); |
2633 | if (!nosec) { | |
2634 | rc = -ENOMEM; | |
2635 | goto out; | |
2636 | } | |
2637 | ||
2638 | nosec_save = nosec; | |
2639 | fnosec = fsec = 1; | |
2640 | in_save = in_end = orig; | |
2641 | ||
2642 | do { | |
3528a953 CO |
2643 | if (*in_end == '"') |
2644 | open_quote = !open_quote; | |
2645 | if ((*in_end == ',' && open_quote == 0) || | |
2646 | *in_end == '\0') { | |
1da177e4 LT |
2647 | int len = in_end - in_curr; |
2648 | ||
2649 | if (selinux_option(in_curr, len)) | |
3528a953 | 2650 | take_selinux_option(&sec_curr, in_curr, &fsec, len); |
1da177e4 LT |
2651 | else |
2652 | take_option(&nosec, in_curr, &fnosec, len); | |
2653 | ||
2654 | in_curr = in_end + 1; | |
2655 | } | |
2656 | } while (*in_end++); | |
2657 | ||
6931dfc9 | 2658 | strcpy(in_save, nosec_save); |
da3caa20 | 2659 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
2660 | out: |
2661 | return rc; | |
2662 | } | |
2663 | ||
026eb167 EP |
2664 | static int selinux_sb_remount(struct super_block *sb, void *data) |
2665 | { | |
2666 | int rc, i, *flags; | |
2667 | struct security_mnt_opts opts; | |
2668 | char *secdata, **mount_options; | |
2669 | struct superblock_security_struct *sbsec = sb->s_security; | |
2670 | ||
2671 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2672 | return 0; | |
2673 | ||
2674 | if (!data) | |
2675 | return 0; | |
2676 | ||
2677 | if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) | |
2678 | return 0; | |
2679 | ||
2680 | security_init_mnt_opts(&opts); | |
2681 | secdata = alloc_secdata(); | |
2682 | if (!secdata) | |
2683 | return -ENOMEM; | |
2684 | rc = selinux_sb_copy_data(data, secdata); | |
2685 | if (rc) | |
2686 | goto out_free_secdata; | |
2687 | ||
2688 | rc = selinux_parse_opts_str(secdata, &opts); | |
2689 | if (rc) | |
2690 | goto out_free_secdata; | |
2691 | ||
2692 | mount_options = opts.mnt_opts; | |
2693 | flags = opts.mnt_opts_flags; | |
2694 | ||
2695 | for (i = 0; i < opts.num_mnt_opts; i++) { | |
2696 | u32 sid; | |
026eb167 | 2697 | |
12f348b9 | 2698 | if (flags[i] == SBLABEL_MNT) |
026eb167 | 2699 | continue; |
44be2f65 | 2700 | rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL); |
026eb167 | 2701 | if (rc) { |
44be2f65 | 2702 | printk(KERN_WARNING "SELinux: security_context_str_to_sid" |
29b1deb2 LT |
2703 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
2704 | mount_options[i], sb->s_id, sb->s_type->name, rc); | |
026eb167 EP |
2705 | goto out_free_opts; |
2706 | } | |
2707 | rc = -EINVAL; | |
2708 | switch (flags[i]) { | |
2709 | case FSCONTEXT_MNT: | |
2710 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) | |
2711 | goto out_bad_option; | |
2712 | break; | |
2713 | case CONTEXT_MNT: | |
2714 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2715 | goto out_bad_option; | |
2716 | break; | |
2717 | case ROOTCONTEXT_MNT: { | |
2718 | struct inode_security_struct *root_isec; | |
83da53c5 | 2719 | root_isec = backing_inode_security(sb->s_root); |
026eb167 EP |
2720 | |
2721 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2722 | goto out_bad_option; | |
2723 | break; | |
2724 | } | |
2725 | case DEFCONTEXT_MNT: | |
2726 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2727 | goto out_bad_option; | |
2728 | break; | |
2729 | default: | |
2730 | goto out_free_opts; | |
2731 | } | |
2732 | } | |
2733 | ||
2734 | rc = 0; | |
2735 | out_free_opts: | |
2736 | security_free_mnt_opts(&opts); | |
2737 | out_free_secdata: | |
2738 | free_secdata(secdata); | |
2739 | return rc; | |
2740 | out_bad_option: | |
2741 | printk(KERN_WARNING "SELinux: unable to change security options " | |
29b1deb2 LT |
2742 | "during remount (dev %s, type=%s)\n", sb->s_id, |
2743 | sb->s_type->name); | |
026eb167 EP |
2744 | goto out_free_opts; |
2745 | } | |
2746 | ||
12204e24 | 2747 | static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) |
1da177e4 | 2748 | { |
88e67f3b | 2749 | const struct cred *cred = current_cred(); |
2bf49690 | 2750 | struct common_audit_data ad; |
1da177e4 LT |
2751 | int rc; |
2752 | ||
2753 | rc = superblock_doinit(sb, data); | |
2754 | if (rc) | |
2755 | return rc; | |
2756 | ||
74192246 JM |
2757 | /* Allow all mounts performed by the kernel */ |
2758 | if (flags & MS_KERNMOUNT) | |
2759 | return 0; | |
2760 | ||
50c205f5 | 2761 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2762 | ad.u.dentry = sb->s_root; |
88e67f3b | 2763 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2764 | } |
2765 | ||
726c3342 | 2766 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2767 | { |
88e67f3b | 2768 | const struct cred *cred = current_cred(); |
2bf49690 | 2769 | struct common_audit_data ad; |
1da177e4 | 2770 | |
50c205f5 | 2771 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2772 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2773 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2774 | } |
2775 | ||
808d4e3c | 2776 | static int selinux_mount(const char *dev_name, |
8a04c43b | 2777 | const struct path *path, |
808d4e3c | 2778 | const char *type, |
828dfe1d EP |
2779 | unsigned long flags, |
2780 | void *data) | |
1da177e4 | 2781 | { |
88e67f3b | 2782 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2783 | |
2784 | if (flags & MS_REMOUNT) | |
d8c9584e | 2785 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2786 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2787 | else |
2875fa00 | 2788 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2789 | } |
2790 | ||
2791 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2792 | { | |
88e67f3b | 2793 | const struct cred *cred = current_cred(); |
1da177e4 | 2794 | |
88e67f3b | 2795 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2796 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2797 | } |
2798 | ||
2799 | /* inode security operations */ | |
2800 | ||
2801 | static int selinux_inode_alloc_security(struct inode *inode) | |
2802 | { | |
2803 | return inode_alloc_security(inode); | |
2804 | } | |
2805 | ||
2806 | static void selinux_inode_free_security(struct inode *inode) | |
2807 | { | |
2808 | inode_free_security(inode); | |
2809 | } | |
2810 | ||
d47be3df DQ |
2811 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
2812 | struct qstr *name, void **ctx, | |
2813 | u32 *ctxlen) | |
2814 | { | |
d47be3df DQ |
2815 | u32 newsid; |
2816 | int rc; | |
2817 | ||
c3c188b2 DH |
2818 | rc = selinux_determine_inode_label(d_inode(dentry->d_parent), name, |
2819 | inode_mode_to_security_class(mode), | |
2820 | &newsid); | |
2821 | if (rc) | |
2822 | return rc; | |
d47be3df DQ |
2823 | |
2824 | return security_sid_to_context(newsid, (char **)ctx, ctxlen); | |
2825 | } | |
2826 | ||
5e41ff9e | 2827 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
2828 | const struct qstr *qstr, |
2829 | const char **name, | |
2a7dba39 | 2830 | void **value, size_t *len) |
5e41ff9e | 2831 | { |
5fb49870 | 2832 | const struct task_security_struct *tsec = current_security(); |
5e41ff9e | 2833 | struct superblock_security_struct *sbsec; |
275bb41e | 2834 | u32 sid, newsid, clen; |
5e41ff9e | 2835 | int rc; |
9548906b | 2836 | char *context; |
5e41ff9e | 2837 | |
5e41ff9e | 2838 | sbsec = dir->i_sb->s_security; |
5e41ff9e | 2839 | |
275bb41e DH |
2840 | sid = tsec->sid; |
2841 | newsid = tsec->create_sid; | |
2842 | ||
c3c188b2 DH |
2843 | rc = selinux_determine_inode_label( |
2844 | dir, qstr, | |
2845 | inode_mode_to_security_class(inode->i_mode), | |
2846 | &newsid); | |
2847 | if (rc) | |
2848 | return rc; | |
5e41ff9e | 2849 | |
296fddf7 | 2850 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 2851 | if (sbsec->flags & SE_SBINITIALIZED) { |
296fddf7 EP |
2852 | struct inode_security_struct *isec = inode->i_security; |
2853 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
2854 | isec->sid = newsid; | |
6f3be9f5 | 2855 | isec->initialized = LABEL_INITIALIZED; |
296fddf7 | 2856 | } |
5e41ff9e | 2857 | |
12f348b9 | 2858 | if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT)) |
25a74f3b SS |
2859 | return -EOPNOTSUPP; |
2860 | ||
9548906b TH |
2861 | if (name) |
2862 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 2863 | |
570bc1c2 | 2864 | if (value && len) { |
12b29f34 | 2865 | rc = security_sid_to_context_force(newsid, &context, &clen); |
9548906b | 2866 | if (rc) |
570bc1c2 | 2867 | return rc; |
570bc1c2 SS |
2868 | *value = context; |
2869 | *len = clen; | |
5e41ff9e | 2870 | } |
5e41ff9e | 2871 | |
5e41ff9e SS |
2872 | return 0; |
2873 | } | |
2874 | ||
4acdaf27 | 2875 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
2876 | { |
2877 | return may_create(dir, dentry, SECCLASS_FILE); | |
2878 | } | |
2879 | ||
1da177e4 LT |
2880 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2881 | { | |
1da177e4 LT |
2882 | return may_link(dir, old_dentry, MAY_LINK); |
2883 | } | |
2884 | ||
1da177e4 LT |
2885 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2886 | { | |
1da177e4 LT |
2887 | return may_link(dir, dentry, MAY_UNLINK); |
2888 | } | |
2889 | ||
2890 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2891 | { | |
2892 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2893 | } | |
2894 | ||
18bb1db3 | 2895 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
2896 | { |
2897 | return may_create(dir, dentry, SECCLASS_DIR); | |
2898 | } | |
2899 | ||
1da177e4 LT |
2900 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2901 | { | |
2902 | return may_link(dir, dentry, MAY_RMDIR); | |
2903 | } | |
2904 | ||
1a67aafb | 2905 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 2906 | { |
1da177e4 LT |
2907 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
2908 | } | |
2909 | ||
1da177e4 | 2910 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 2911 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
2912 | { |
2913 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2914 | } | |
2915 | ||
1da177e4 LT |
2916 | static int selinux_inode_readlink(struct dentry *dentry) |
2917 | { | |
88e67f3b DH |
2918 | const struct cred *cred = current_cred(); |
2919 | ||
2875fa00 | 2920 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
2921 | } |
2922 | ||
bda0be7a N |
2923 | static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, |
2924 | bool rcu) | |
1da177e4 | 2925 | { |
88e67f3b | 2926 | const struct cred *cred = current_cred(); |
bda0be7a N |
2927 | struct common_audit_data ad; |
2928 | struct inode_security_struct *isec; | |
2929 | u32 sid; | |
1da177e4 | 2930 | |
bda0be7a N |
2931 | validate_creds(cred); |
2932 | ||
2933 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
2934 | ad.u.dentry = dentry; | |
2935 | sid = cred_sid(cred); | |
5d226df4 AG |
2936 | isec = inode_security_rcu(inode, rcu); |
2937 | if (IS_ERR(isec)) | |
2938 | return PTR_ERR(isec); | |
bda0be7a N |
2939 | |
2940 | return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad, | |
2941 | rcu ? MAY_NOT_BLOCK : 0); | |
1da177e4 LT |
2942 | } |
2943 | ||
d4cf970d EP |
2944 | static noinline int audit_inode_permission(struct inode *inode, |
2945 | u32 perms, u32 audited, u32 denied, | |
626b9740 | 2946 | int result, |
d4cf970d | 2947 | unsigned flags) |
1da177e4 | 2948 | { |
b782e0a6 | 2949 | struct common_audit_data ad; |
d4cf970d EP |
2950 | struct inode_security_struct *isec = inode->i_security; |
2951 | int rc; | |
2952 | ||
50c205f5 | 2953 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
2954 | ad.u.inode = inode; |
2955 | ||
2956 | rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, | |
626b9740 | 2957 | audited, denied, result, &ad, flags); |
d4cf970d EP |
2958 | if (rc) |
2959 | return rc; | |
2960 | return 0; | |
2961 | } | |
2962 | ||
e74f71eb | 2963 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 2964 | { |
88e67f3b | 2965 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
2966 | u32 perms; |
2967 | bool from_access; | |
cf1dd1da | 2968 | unsigned flags = mask & MAY_NOT_BLOCK; |
2e334057 EP |
2969 | struct inode_security_struct *isec; |
2970 | u32 sid; | |
2971 | struct av_decision avd; | |
2972 | int rc, rc2; | |
2973 | u32 audited, denied; | |
1da177e4 | 2974 | |
b782e0a6 | 2975 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
2976 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
2977 | ||
b782e0a6 EP |
2978 | /* No permission to check. Existence test. */ |
2979 | if (!mask) | |
1da177e4 | 2980 | return 0; |
1da177e4 | 2981 | |
2e334057 | 2982 | validate_creds(cred); |
b782e0a6 | 2983 | |
2e334057 EP |
2984 | if (unlikely(IS_PRIVATE(inode))) |
2985 | return 0; | |
b782e0a6 EP |
2986 | |
2987 | perms = file_mask_to_av(inode->i_mode, mask); | |
2988 | ||
2e334057 | 2989 | sid = cred_sid(cred); |
5d226df4 AG |
2990 | isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK); |
2991 | if (IS_ERR(isec)) | |
2992 | return PTR_ERR(isec); | |
2e334057 EP |
2993 | |
2994 | rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd); | |
2995 | audited = avc_audit_required(perms, &avd, rc, | |
2996 | from_access ? FILE__AUDIT_ACCESS : 0, | |
2997 | &denied); | |
2998 | if (likely(!audited)) | |
2999 | return rc; | |
3000 | ||
626b9740 | 3001 | rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags); |
2e334057 EP |
3002 | if (rc2) |
3003 | return rc2; | |
3004 | return rc; | |
1da177e4 LT |
3005 | } |
3006 | ||
3007 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
3008 | { | |
88e67f3b | 3009 | const struct cred *cred = current_cred(); |
bc6a6008 | 3010 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 3011 | __u32 av = FILE__WRITE; |
1da177e4 | 3012 | |
bc6a6008 AW |
3013 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
3014 | if (ia_valid & ATTR_FORCE) { | |
3015 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
3016 | ATTR_FORCE); | |
3017 | if (!ia_valid) | |
3018 | return 0; | |
3019 | } | |
1da177e4 | 3020 | |
bc6a6008 AW |
3021 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
3022 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 3023 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 3024 | |
44d37ad3 JVS |
3025 | if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE) |
3026 | && !(ia_valid & ATTR_FILE)) | |
95dbf739 EP |
3027 | av |= FILE__OPEN; |
3028 | ||
3029 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
3030 | } |
3031 | ||
3f7036a0 | 3032 | static int selinux_inode_getattr(const struct path *path) |
1da177e4 | 3033 | { |
3f7036a0 | 3034 | return path_has_perm(current_cred(), path, FILE__GETATTR); |
1da177e4 LT |
3035 | } |
3036 | ||
8f0cfa52 | 3037 | static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) |
b5376771 | 3038 | { |
88e67f3b DH |
3039 | const struct cred *cred = current_cred(); |
3040 | ||
b5376771 SH |
3041 | if (!strncmp(name, XATTR_SECURITY_PREFIX, |
3042 | sizeof XATTR_SECURITY_PREFIX - 1)) { | |
3043 | if (!strcmp(name, XATTR_NAME_CAPS)) { | |
3044 | if (!capable(CAP_SETFCAP)) | |
3045 | return -EPERM; | |
3046 | } else if (!capable(CAP_SYS_ADMIN)) { | |
3047 | /* A different attribute in the security namespace. | |
3048 | Restrict to administrator. */ | |
3049 | return -EPERM; | |
3050 | } | |
3051 | } | |
3052 | ||
3053 | /* Not an attribute we recognize, so just check the | |
3054 | ordinary setattr permission. */ | |
2875fa00 | 3055 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
b5376771 SH |
3056 | } |
3057 | ||
8f0cfa52 DH |
3058 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
3059 | const void *value, size_t size, int flags) | |
1da177e4 | 3060 | { |
c6f493d6 | 3061 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3062 | struct inode_security_struct *isec; |
1da177e4 | 3063 | struct superblock_security_struct *sbsec; |
2bf49690 | 3064 | struct common_audit_data ad; |
275bb41e | 3065 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
3066 | int rc = 0; |
3067 | ||
b5376771 SH |
3068 | if (strcmp(name, XATTR_NAME_SELINUX)) |
3069 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
3070 | |
3071 | sbsec = inode->i_sb->s_security; | |
12f348b9 | 3072 | if (!(sbsec->flags & SBLABEL_MNT)) |
1da177e4 LT |
3073 | return -EOPNOTSUPP; |
3074 | ||
2e149670 | 3075 | if (!inode_owner_or_capable(inode)) |
1da177e4 LT |
3076 | return -EPERM; |
3077 | ||
50c205f5 | 3078 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 3079 | ad.u.dentry = dentry; |
1da177e4 | 3080 | |
20cdef8d | 3081 | isec = backing_inode_security(dentry); |
275bb41e | 3082 | rc = avc_has_perm(sid, isec->sid, isec->sclass, |
1da177e4 LT |
3083 | FILE__RELABELFROM, &ad); |
3084 | if (rc) | |
3085 | return rc; | |
3086 | ||
52a4c640 | 3087 | rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); |
12b29f34 | 3088 | if (rc == -EINVAL) { |
d6ea83ec EP |
3089 | if (!capable(CAP_MAC_ADMIN)) { |
3090 | struct audit_buffer *ab; | |
3091 | size_t audit_size; | |
3092 | const char *str; | |
3093 | ||
3094 | /* We strip a nul only if it is at the end, otherwise the | |
3095 | * context contains a nul and we should audit that */ | |
e3fea3f7 AV |
3096 | if (value) { |
3097 | str = value; | |
3098 | if (str[size - 1] == '\0') | |
3099 | audit_size = size - 1; | |
3100 | else | |
3101 | audit_size = size; | |
3102 | } else { | |
3103 | str = ""; | |
3104 | audit_size = 0; | |
3105 | } | |
d6ea83ec EP |
3106 | ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); |
3107 | audit_log_format(ab, "op=setxattr invalid_context="); | |
3108 | audit_log_n_untrustedstring(ab, value, audit_size); | |
3109 | audit_log_end(ab); | |
3110 | ||
12b29f34 | 3111 | return rc; |
d6ea83ec | 3112 | } |
12b29f34 SS |
3113 | rc = security_context_to_sid_force(value, size, &newsid); |
3114 | } | |
1da177e4 LT |
3115 | if (rc) |
3116 | return rc; | |
3117 | ||
275bb41e | 3118 | rc = avc_has_perm(sid, newsid, isec->sclass, |
1da177e4 LT |
3119 | FILE__RELABELTO, &ad); |
3120 | if (rc) | |
3121 | return rc; | |
3122 | ||
275bb41e | 3123 | rc = security_validate_transition(isec->sid, newsid, sid, |
828dfe1d | 3124 | isec->sclass); |
1da177e4 LT |
3125 | if (rc) |
3126 | return rc; | |
3127 | ||
3128 | return avc_has_perm(newsid, | |
3129 | sbsec->sid, | |
3130 | SECCLASS_FILESYSTEM, | |
3131 | FILESYSTEM__ASSOCIATE, | |
3132 | &ad); | |
3133 | } | |
3134 | ||
8f0cfa52 | 3135 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 3136 | const void *value, size_t size, |
8f0cfa52 | 3137 | int flags) |
1da177e4 | 3138 | { |
c6f493d6 | 3139 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3140 | struct inode_security_struct *isec; |
1da177e4 LT |
3141 | u32 newsid; |
3142 | int rc; | |
3143 | ||
3144 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
3145 | /* Not an attribute we recognize, so nothing to do. */ | |
3146 | return; | |
3147 | } | |
3148 | ||
12b29f34 | 3149 | rc = security_context_to_sid_force(value, size, &newsid); |
1da177e4 | 3150 | if (rc) { |
12b29f34 SS |
3151 | printk(KERN_ERR "SELinux: unable to map context to SID" |
3152 | "for (%s, %lu), rc=%d\n", | |
3153 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
3154 | return; |
3155 | } | |
3156 | ||
20cdef8d | 3157 | isec = backing_inode_security(dentry); |
aa9c2669 | 3158 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3159 | isec->sid = newsid; |
6f3be9f5 | 3160 | isec->initialized = LABEL_INITIALIZED; |
aa9c2669 | 3161 | |
1da177e4 LT |
3162 | return; |
3163 | } | |
3164 | ||
8f0cfa52 | 3165 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 3166 | { |
88e67f3b DH |
3167 | const struct cred *cred = current_cred(); |
3168 | ||
2875fa00 | 3169 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3170 | } |
3171 | ||
828dfe1d | 3172 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 3173 | { |
88e67f3b DH |
3174 | const struct cred *cred = current_cred(); |
3175 | ||
2875fa00 | 3176 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3177 | } |
3178 | ||
8f0cfa52 | 3179 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 3180 | { |
b5376771 SH |
3181 | if (strcmp(name, XATTR_NAME_SELINUX)) |
3182 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
3183 | |
3184 | /* No one is allowed to remove a SELinux security label. | |
3185 | You can change the label, but all data must be labeled. */ | |
3186 | return -EACCES; | |
3187 | } | |
3188 | ||
d381d8a9 | 3189 | /* |
abc69bb6 | 3190 | * Copy the inode security context value to the user. |
d381d8a9 JM |
3191 | * |
3192 | * Permission check is handled by selinux_inode_getxattr hook. | |
3193 | */ | |
ea861dfd | 3194 | static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 3195 | { |
42492594 DQ |
3196 | u32 size; |
3197 | int error; | |
3198 | char *context = NULL; | |
20cdef8d | 3199 | struct inode_security_struct *isec; |
d381d8a9 | 3200 | |
8c8570fb DK |
3201 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
3202 | return -EOPNOTSUPP; | |
d381d8a9 | 3203 | |
abc69bb6 SS |
3204 | /* |
3205 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3206 | * value even if it is not defined by current policy; otherwise, | |
3207 | * use the in-core value under current policy. | |
3208 | * Use the non-auditing forms of the permission checks since | |
3209 | * getxattr may be called by unprivileged processes commonly | |
3210 | * and lack of permission just means that we fall back to the | |
3211 | * in-core context value, not a denial. | |
3212 | */ | |
b1d9e6b0 CS |
3213 | error = cap_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN, |
3214 | SECURITY_CAP_NOAUDIT); | |
3215 | if (!error) | |
3216 | error = cred_has_capability(current_cred(), CAP_MAC_ADMIN, | |
8e4ff6f2 | 3217 | SECURITY_CAP_NOAUDIT, true); |
20cdef8d | 3218 | isec = inode_security(inode); |
abc69bb6 SS |
3219 | if (!error) |
3220 | error = security_sid_to_context_force(isec->sid, &context, | |
3221 | &size); | |
3222 | else | |
3223 | error = security_sid_to_context(isec->sid, &context, &size); | |
42492594 DQ |
3224 | if (error) |
3225 | return error; | |
3226 | error = size; | |
3227 | if (alloc) { | |
3228 | *buffer = context; | |
3229 | goto out_nofree; | |
3230 | } | |
3231 | kfree(context); | |
3232 | out_nofree: | |
3233 | return error; | |
1da177e4 LT |
3234 | } |
3235 | ||
3236 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 3237 | const void *value, size_t size, int flags) |
1da177e4 | 3238 | { |
2c97165b | 3239 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
1da177e4 LT |
3240 | u32 newsid; |
3241 | int rc; | |
3242 | ||
3243 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3244 | return -EOPNOTSUPP; | |
3245 | ||
3246 | if (!value || !size) | |
3247 | return -EACCES; | |
3248 | ||
20ba96ae | 3249 | rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); |
1da177e4 LT |
3250 | if (rc) |
3251 | return rc; | |
3252 | ||
aa9c2669 | 3253 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3254 | isec->sid = newsid; |
6f3be9f5 | 3255 | isec->initialized = LABEL_INITIALIZED; |
1da177e4 LT |
3256 | return 0; |
3257 | } | |
3258 | ||
3259 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3260 | { | |
3261 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3262 | if (buffer && len <= buffer_size) | |
3263 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3264 | return len; | |
3265 | } | |
3266 | ||
d6335d77 | 3267 | static void selinux_inode_getsecid(struct inode *inode, u32 *secid) |
713a04ae | 3268 | { |
e817c2f3 | 3269 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
713a04ae AD |
3270 | *secid = isec->sid; |
3271 | } | |
3272 | ||
1da177e4 LT |
3273 | /* file security operations */ |
3274 | ||
788e7dd4 | 3275 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3276 | { |
88e67f3b | 3277 | const struct cred *cred = current_cred(); |
496ad9aa | 3278 | struct inode *inode = file_inode(file); |
1da177e4 | 3279 | |
1da177e4 LT |
3280 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3281 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3282 | mask |= MAY_APPEND; | |
3283 | ||
389fb800 PM |
3284 | return file_has_perm(cred, file, |
3285 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3286 | } |
3287 | ||
788e7dd4 YN |
3288 | static int selinux_file_permission(struct file *file, int mask) |
3289 | { | |
496ad9aa | 3290 | struct inode *inode = file_inode(file); |
20dda18b | 3291 | struct file_security_struct *fsec = file->f_security; |
b197367e | 3292 | struct inode_security_struct *isec; |
20dda18b SS |
3293 | u32 sid = current_sid(); |
3294 | ||
389fb800 | 3295 | if (!mask) |
788e7dd4 YN |
3296 | /* No permission to check. Existence test. */ |
3297 | return 0; | |
788e7dd4 | 3298 | |
b197367e | 3299 | isec = inode_security(inode); |
20dda18b SS |
3300 | if (sid == fsec->sid && fsec->isid == isec->sid && |
3301 | fsec->pseqno == avc_policy_seqno()) | |
83d49856 | 3302 | /* No change since file_open check. */ |
20dda18b SS |
3303 | return 0; |
3304 | ||
788e7dd4 YN |
3305 | return selinux_revalidate_file_permission(file, mask); |
3306 | } | |
3307 | ||
1da177e4 LT |
3308 | static int selinux_file_alloc_security(struct file *file) |
3309 | { | |
3310 | return file_alloc_security(file); | |
3311 | } | |
3312 | ||
3313 | static void selinux_file_free_security(struct file *file) | |
3314 | { | |
3315 | file_free_security(file); | |
3316 | } | |
3317 | ||
fa1aa143 JVS |
3318 | /* |
3319 | * Check whether a task has the ioctl permission and cmd | |
3320 | * operation to an inode. | |
3321 | */ | |
1d2a168a | 3322 | static int ioctl_has_perm(const struct cred *cred, struct file *file, |
fa1aa143 JVS |
3323 | u32 requested, u16 cmd) |
3324 | { | |
3325 | struct common_audit_data ad; | |
3326 | struct file_security_struct *fsec = file->f_security; | |
3327 | struct inode *inode = file_inode(file); | |
20cdef8d | 3328 | struct inode_security_struct *isec; |
fa1aa143 JVS |
3329 | struct lsm_ioctlop_audit ioctl; |
3330 | u32 ssid = cred_sid(cred); | |
3331 | int rc; | |
3332 | u8 driver = cmd >> 8; | |
3333 | u8 xperm = cmd & 0xff; | |
3334 | ||
3335 | ad.type = LSM_AUDIT_DATA_IOCTL_OP; | |
3336 | ad.u.op = &ioctl; | |
3337 | ad.u.op->cmd = cmd; | |
3338 | ad.u.op->path = file->f_path; | |
3339 | ||
3340 | if (ssid != fsec->sid) { | |
3341 | rc = avc_has_perm(ssid, fsec->sid, | |
3342 | SECCLASS_FD, | |
3343 | FD__USE, | |
3344 | &ad); | |
3345 | if (rc) | |
3346 | goto out; | |
3347 | } | |
3348 | ||
3349 | if (unlikely(IS_PRIVATE(inode))) | |
3350 | return 0; | |
3351 | ||
20cdef8d | 3352 | isec = inode_security(inode); |
fa1aa143 JVS |
3353 | rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, |
3354 | requested, driver, xperm, &ad); | |
3355 | out: | |
3356 | return rc; | |
3357 | } | |
3358 | ||
1da177e4 LT |
3359 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
3360 | unsigned long arg) | |
3361 | { | |
88e67f3b | 3362 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3363 | int error = 0; |
1da177e4 | 3364 | |
0b24dcb7 EP |
3365 | switch (cmd) { |
3366 | case FIONREAD: | |
3367 | /* fall through */ | |
3368 | case FIBMAP: | |
3369 | /* fall through */ | |
3370 | case FIGETBSZ: | |
3371 | /* fall through */ | |
2f99c369 | 3372 | case FS_IOC_GETFLAGS: |
0b24dcb7 | 3373 | /* fall through */ |
2f99c369 | 3374 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3375 | error = file_has_perm(cred, file, FILE__GETATTR); |
3376 | break; | |
1da177e4 | 3377 | |
2f99c369 | 3378 | case FS_IOC_SETFLAGS: |
0b24dcb7 | 3379 | /* fall through */ |
2f99c369 | 3380 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3381 | error = file_has_perm(cred, file, FILE__SETATTR); |
3382 | break; | |
3383 | ||
3384 | /* sys_ioctl() checks */ | |
3385 | case FIONBIO: | |
3386 | /* fall through */ | |
3387 | case FIOASYNC: | |
3388 | error = file_has_perm(cred, file, 0); | |
3389 | break; | |
1da177e4 | 3390 | |
0b24dcb7 EP |
3391 | case KDSKBENT: |
3392 | case KDSKBSENT: | |
6a9de491 | 3393 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
8e4ff6f2 | 3394 | SECURITY_CAP_AUDIT, true); |
0b24dcb7 EP |
3395 | break; |
3396 | ||
3397 | /* default case assumes that the command will go | |
3398 | * to the file's ioctl() function. | |
3399 | */ | |
3400 | default: | |
fa1aa143 | 3401 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
0b24dcb7 EP |
3402 | } |
3403 | return error; | |
1da177e4 LT |
3404 | } |
3405 | ||
fcaaade1 SS |
3406 | static int default_noexec; |
3407 | ||
1da177e4 LT |
3408 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3409 | { | |
88e67f3b | 3410 | const struct cred *cred = current_cred(); |
d84f4f99 | 3411 | int rc = 0; |
88e67f3b | 3412 | |
fcaaade1 | 3413 | if (default_noexec && |
892e8cac SS |
3414 | (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || |
3415 | (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3416 | /* |
3417 | * We are making executable an anonymous mapping or a | |
3418 | * private file mapping that will also be writable. | |
3419 | * This has an additional check. | |
3420 | */ | |
d84f4f99 | 3421 | rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); |
1da177e4 | 3422 | if (rc) |
d84f4f99 | 3423 | goto error; |
1da177e4 | 3424 | } |
1da177e4 LT |
3425 | |
3426 | if (file) { | |
3427 | /* read access is always possible with a mapping */ | |
3428 | u32 av = FILE__READ; | |
3429 | ||
3430 | /* write access only matters if the mapping is shared */ | |
3431 | if (shared && (prot & PROT_WRITE)) | |
3432 | av |= FILE__WRITE; | |
3433 | ||
3434 | if (prot & PROT_EXEC) | |
3435 | av |= FILE__EXECUTE; | |
3436 | ||
88e67f3b | 3437 | return file_has_perm(cred, file, av); |
1da177e4 | 3438 | } |
d84f4f99 DH |
3439 | |
3440 | error: | |
3441 | return rc; | |
1da177e4 LT |
3442 | } |
3443 | ||
e5467859 | 3444 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3445 | { |
b1d9e6b0 | 3446 | int rc = 0; |
1da177e4 | 3447 | |
a2551df7 | 3448 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
98883bfd | 3449 | u32 sid = current_sid(); |
ed032189 EP |
3450 | rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, |
3451 | MEMPROTECT__MMAP_ZERO, NULL); | |
84336d1a EP |
3452 | } |
3453 | ||
98883bfd | 3454 | return rc; |
e5467859 | 3455 | } |
1da177e4 | 3456 | |
e5467859 AV |
3457 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3458 | unsigned long prot, unsigned long flags) | |
3459 | { | |
1da177e4 LT |
3460 | if (selinux_checkreqprot) |
3461 | prot = reqprot; | |
3462 | ||
3463 | return file_map_prot_check(file, prot, | |
3464 | (flags & MAP_TYPE) == MAP_SHARED); | |
3465 | } | |
3466 | ||
3467 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3468 | unsigned long reqprot, | |
3469 | unsigned long prot) | |
3470 | { | |
88e67f3b | 3471 | const struct cred *cred = current_cred(); |
1da177e4 LT |
3472 | |
3473 | if (selinux_checkreqprot) | |
3474 | prot = reqprot; | |
3475 | ||
fcaaade1 SS |
3476 | if (default_noexec && |
3477 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3478 | int rc = 0; |
db4c9641 SS |
3479 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3480 | vma->vm_end <= vma->vm_mm->brk) { | |
d84f4f99 | 3481 | rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); |
db4c9641 | 3482 | } else if (!vma->vm_file && |
c2316dbf SS |
3483 | ((vma->vm_start <= vma->vm_mm->start_stack && |
3484 | vma->vm_end >= vma->vm_mm->start_stack) || | |
3485 | vma_is_stack_for_task(vma, current))) { | |
3b11a1de | 3486 | rc = current_has_perm(current, PROCESS__EXECSTACK); |
db4c9641 SS |
3487 | } else if (vma->vm_file && vma->anon_vma) { |
3488 | /* | |
3489 | * We are making executable a file mapping that has | |
3490 | * had some COW done. Since pages might have been | |
3491 | * written, check ability to execute the possibly | |
3492 | * modified content. This typically should only | |
3493 | * occur for text relocations. | |
3494 | */ | |
d84f4f99 | 3495 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3496 | } |