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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> |
3a976fa6 | 20 | * Copyright (C) 2016 Mellanox Technologies |
1da177e4 LT |
21 | * |
22 | * This program is free software; you can redistribute it and/or modify | |
23 | * it under the terms of the GNU General Public License version 2, | |
828dfe1d | 24 | * as published by the Free Software Foundation. |
1da177e4 LT |
25 | */ |
26 | ||
1da177e4 | 27 | #include <linux/init.h> |
0b24dcb7 | 28 | #include <linux/kd.h> |
1da177e4 | 29 | #include <linux/kernel.h> |
0d094efe | 30 | #include <linux/tracehook.h> |
1da177e4 | 31 | #include <linux/errno.h> |
3f07c014 | 32 | #include <linux/sched/signal.h> |
29930025 | 33 | #include <linux/sched/task.h> |
3c4ed7bd | 34 | #include <linux/lsm_hooks.h> |
1da177e4 LT |
35 | #include <linux/xattr.h> |
36 | #include <linux/capability.h> | |
37 | #include <linux/unistd.h> | |
38 | #include <linux/mm.h> | |
39 | #include <linux/mman.h> | |
40 | #include <linux/slab.h> | |
41 | #include <linux/pagemap.h> | |
0b24dcb7 | 42 | #include <linux/proc_fs.h> |
1da177e4 | 43 | #include <linux/swap.h> |
1da177e4 LT |
44 | #include <linux/spinlock.h> |
45 | #include <linux/syscalls.h> | |
2a7dba39 | 46 | #include <linux/dcache.h> |
1da177e4 | 47 | #include <linux/file.h> |
9f3acc31 | 48 | #include <linux/fdtable.h> |
1da177e4 LT |
49 | #include <linux/namei.h> |
50 | #include <linux/mount.h> | |
1da177e4 LT |
51 | #include <linux/netfilter_ipv4.h> |
52 | #include <linux/netfilter_ipv6.h> | |
53 | #include <linux/tty.h> | |
54 | #include <net/icmp.h> | |
227b60f5 | 55 | #include <net/ip.h> /* for local_port_range[] */ |
1da177e4 | 56 | #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ |
47180068 | 57 | #include <net/inet_connection_sock.h> |
220deb96 | 58 | #include <net/net_namespace.h> |
d621d35e | 59 | #include <net/netlabel.h> |
f5269710 | 60 | #include <linux/uaccess.h> |
1da177e4 | 61 | #include <asm/ioctls.h> |
60063497 | 62 | #include <linux/atomic.h> |
1da177e4 LT |
63 | #include <linux/bitops.h> |
64 | #include <linux/interrupt.h> | |
65 | #include <linux/netdevice.h> /* for network interface checks */ | |
77954983 | 66 | #include <net/netlink.h> |
1da177e4 LT |
67 | #include <linux/tcp.h> |
68 | #include <linux/udp.h> | |
2ee92d46 | 69 | #include <linux/dccp.h> |
1da177e4 LT |
70 | #include <linux/quota.h> |
71 | #include <linux/un.h> /* for Unix socket types */ | |
72 | #include <net/af_unix.h> /* for Unix socket types */ | |
73 | #include <linux/parser.h> | |
74 | #include <linux/nfs_mount.h> | |
75 | #include <net/ipv6.h> | |
76 | #include <linux/hugetlb.h> | |
77 | #include <linux/personality.h> | |
1da177e4 | 78 | #include <linux/audit.h> |
6931dfc9 | 79 | #include <linux/string.h> |
877ce7c1 | 80 | #include <linux/selinux.h> |
23970741 | 81 | #include <linux/mutex.h> |
f06febc9 | 82 | #include <linux/posix-timers.h> |
00234592 | 83 | #include <linux/syslog.h> |
3486740a | 84 | #include <linux/user_namespace.h> |
44fc7ea0 | 85 | #include <linux/export.h> |
40401530 AV |
86 | #include <linux/msg.h> |
87 | #include <linux/shm.h> | |
1da177e4 LT |
88 | |
89 | #include "avc.h" | |
90 | #include "objsec.h" | |
91 | #include "netif.h" | |
224dfbd8 | 92 | #include "netnode.h" |
3e112172 | 93 | #include "netport.h" |
409dcf31 | 94 | #include "ibpkey.h" |
d28d1e08 | 95 | #include "xfrm.h" |
c60475bf | 96 | #include "netlabel.h" |
9d57a7f9 | 97 | #include "audit.h" |
7b98a585 | 98 | #include "avc_ss.h" |
1da177e4 | 99 | |
d621d35e | 100 | /* SECMARK reference count */ |
56a4ca99 | 101 | static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); |
d621d35e | 102 | |
1da177e4 | 103 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
828dfe1d | 104 | int selinux_enforcing; |
1da177e4 LT |
105 | |
106 | static int __init enforcing_setup(char *str) | |
107 | { | |
f5269710 | 108 | unsigned long enforcing; |
29707b20 | 109 | if (!kstrtoul(str, 0, &enforcing)) |
f5269710 | 110 | selinux_enforcing = enforcing ? 1 : 0; |
1da177e4 LT |
111 | return 1; |
112 | } | |
113 | __setup("enforcing=", enforcing_setup); | |
114 | #endif | |
115 | ||
116 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM | |
117 | int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; | |
118 | ||
119 | static int __init selinux_enabled_setup(char *str) | |
120 | { | |
f5269710 | 121 | unsigned long enabled; |
29707b20 | 122 | if (!kstrtoul(str, 0, &enabled)) |
f5269710 | 123 | selinux_enabled = enabled ? 1 : 0; |
1da177e4 LT |
124 | return 1; |
125 | } | |
126 | __setup("selinux=", selinux_enabled_setup); | |
30d55280 SS |
127 | #else |
128 | int selinux_enabled = 1; | |
1da177e4 LT |
129 | #endif |
130 | ||
e18b890b | 131 | static struct kmem_cache *sel_inode_cache; |
63205654 | 132 | static struct kmem_cache *file_security_cache; |
7cae7e26 | 133 | |
d621d35e PM |
134 | /** |
135 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
136 | * | |
137 | * Description: | |
138 | * This function checks the SECMARK reference counter to see if any SECMARK | |
139 | * targets are currently configured, if the reference counter is greater than | |
140 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
2be4d74f CP |
141 | * enabled, false (0) if SECMARK is disabled. If the always_check_network |
142 | * policy capability is enabled, SECMARK is always considered enabled. | |
d621d35e PM |
143 | * |
144 | */ | |
145 | static int selinux_secmark_enabled(void) | |
146 | { | |
2be4d74f CP |
147 | return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount)); |
148 | } | |
149 | ||
150 | /** | |
151 | * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled | |
152 | * | |
153 | * Description: | |
154 | * This function checks if NetLabel or labeled IPSEC is enabled. Returns true | |
155 | * (1) if any are enabled or false (0) if neither are enabled. If the | |
156 | * always_check_network policy capability is enabled, peer labeling | |
157 | * is always considered enabled. | |
158 | * | |
159 | */ | |
160 | static int selinux_peerlbl_enabled(void) | |
161 | { | |
162 | return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled()); | |
d621d35e PM |
163 | } |
164 | ||
615e51fd PM |
165 | static int selinux_netcache_avc_callback(u32 event) |
166 | { | |
167 | if (event == AVC_CALLBACK_RESET) { | |
168 | sel_netif_flush(); | |
169 | sel_netnode_flush(); | |
170 | sel_netport_flush(); | |
171 | synchronize_net(); | |
172 | } | |
173 | return 0; | |
174 | } | |
175 | ||
8f408ab6 DJ |
176 | static int selinux_lsm_notifier_avc_callback(u32 event) |
177 | { | |
409dcf31 DJ |
178 | if (event == AVC_CALLBACK_RESET) { |
179 | sel_ib_pkey_flush(); | |
8f408ab6 | 180 | call_lsm_notifier(LSM_POLICY_CHANGE, NULL); |
409dcf31 | 181 | } |
8f408ab6 DJ |
182 | |
183 | return 0; | |
184 | } | |
185 | ||
d84f4f99 DH |
186 | /* |
187 | * initialise the security for the init task | |
188 | */ | |
189 | static void cred_init_security(void) | |
1da177e4 | 190 | { |
3b11a1de | 191 | struct cred *cred = (struct cred *) current->real_cred; |
1da177e4 LT |
192 | struct task_security_struct *tsec; |
193 | ||
89d155ef | 194 | tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); |
1da177e4 | 195 | if (!tsec) |
d84f4f99 | 196 | panic("SELinux: Failed to initialize initial task.\n"); |
1da177e4 | 197 | |
d84f4f99 | 198 | tsec->osid = tsec->sid = SECINITSID_KERNEL; |
f1752eec | 199 | cred->security = tsec; |
1da177e4 LT |
200 | } |
201 | ||
88e67f3b DH |
202 | /* |
203 | * get the security ID of a set of credentials | |
204 | */ | |
205 | static inline u32 cred_sid(const struct cred *cred) | |
206 | { | |
207 | const struct task_security_struct *tsec; | |
208 | ||
209 | tsec = cred->security; | |
210 | return tsec->sid; | |
211 | } | |
212 | ||
275bb41e | 213 | /* |
3b11a1de | 214 | * get the objective security ID of a task |
275bb41e DH |
215 | */ |
216 | static inline u32 task_sid(const struct task_struct *task) | |
217 | { | |
275bb41e DH |
218 | u32 sid; |
219 | ||
220 | rcu_read_lock(); | |
88e67f3b | 221 | sid = cred_sid(__task_cred(task)); |
275bb41e DH |
222 | rcu_read_unlock(); |
223 | return sid; | |
224 | } | |
225 | ||
88e67f3b DH |
226 | /* Allocate and free functions for each kind of security blob. */ |
227 | ||
1da177e4 LT |
228 | static int inode_alloc_security(struct inode *inode) |
229 | { | |
1da177e4 | 230 | struct inode_security_struct *isec; |
275bb41e | 231 | u32 sid = current_sid(); |
1da177e4 | 232 | |
a02fe132 | 233 | isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); |
1da177e4 LT |
234 | if (!isec) |
235 | return -ENOMEM; | |
236 | ||
9287aed2 | 237 | spin_lock_init(&isec->lock); |
1da177e4 | 238 | INIT_LIST_HEAD(&isec->list); |
1da177e4 LT |
239 | isec->inode = inode; |
240 | isec->sid = SECINITSID_UNLABELED; | |
241 | isec->sclass = SECCLASS_FILE; | |
275bb41e | 242 | isec->task_sid = sid; |
42059112 | 243 | isec->initialized = LABEL_INVALID; |
1da177e4 LT |
244 | inode->i_security = isec; |
245 | ||
246 | return 0; | |
247 | } | |
248 | ||
5d226df4 AG |
249 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); |
250 | ||
251 | /* | |
252 | * Try reloading inode security labels that have been marked as invalid. The | |
253 | * @may_sleep parameter indicates when sleeping and thus reloading labels is | |
42059112 | 254 | * allowed; when set to false, returns -ECHILD when the label is |
5d226df4 AG |
255 | * invalid. The @opt_dentry parameter should be set to a dentry of the inode; |
256 | * when no dentry is available, set it to NULL instead. | |
257 | */ | |
258 | static int __inode_security_revalidate(struct inode *inode, | |
259 | struct dentry *opt_dentry, | |
260 | bool may_sleep) | |
261 | { | |
262 | struct inode_security_struct *isec = inode->i_security; | |
263 | ||
264 | might_sleep_if(may_sleep); | |
265 | ||
1ac42476 | 266 | if (ss_initialized && isec->initialized != LABEL_INITIALIZED) { |
5d226df4 AG |
267 | if (!may_sleep) |
268 | return -ECHILD; | |
269 | ||
270 | /* | |
271 | * Try reloading the inode security label. This will fail if | |
272 | * @opt_dentry is NULL and no dentry for this inode can be | |
273 | * found; in that case, continue using the old label. | |
274 | */ | |
275 | inode_doinit_with_dentry(inode, opt_dentry); | |
276 | } | |
277 | return 0; | |
278 | } | |
279 | ||
5d226df4 AG |
280 | static struct inode_security_struct *inode_security_novalidate(struct inode *inode) |
281 | { | |
282 | return inode->i_security; | |
283 | } | |
284 | ||
285 | static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) | |
286 | { | |
287 | int error; | |
288 | ||
289 | error = __inode_security_revalidate(inode, NULL, !rcu); | |
290 | if (error) | |
291 | return ERR_PTR(error); | |
292 | return inode->i_security; | |
293 | } | |
294 | ||
83da53c5 AG |
295 | /* |
296 | * Get the security label of an inode. | |
297 | */ | |
298 | static struct inode_security_struct *inode_security(struct inode *inode) | |
299 | { | |
5d226df4 | 300 | __inode_security_revalidate(inode, NULL, true); |
83da53c5 AG |
301 | return inode->i_security; |
302 | } | |
303 | ||
2c97165b PM |
304 | static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) |
305 | { | |
306 | struct inode *inode = d_backing_inode(dentry); | |
307 | ||
308 | return inode->i_security; | |
309 | } | |
310 | ||
83da53c5 AG |
311 | /* |
312 | * Get the security label of a dentry's backing inode. | |
313 | */ | |
314 | static struct inode_security_struct *backing_inode_security(struct dentry *dentry) | |
315 | { | |
316 | struct inode *inode = d_backing_inode(dentry); | |
317 | ||
5d226df4 | 318 | __inode_security_revalidate(inode, dentry, true); |
83da53c5 AG |
319 | return inode->i_security; |
320 | } | |
321 | ||
3dc91d43 SR |
322 | static void inode_free_rcu(struct rcu_head *head) |
323 | { | |
324 | struct inode_security_struct *isec; | |
325 | ||
326 | isec = container_of(head, struct inode_security_struct, rcu); | |
327 | kmem_cache_free(sel_inode_cache, isec); | |
328 | } | |
329 | ||
1da177e4 LT |
330 | static void inode_free_security(struct inode *inode) |
331 | { | |
332 | struct inode_security_struct *isec = inode->i_security; | |
333 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
334 | ||
9629d04a WL |
335 | /* |
336 | * As not all inode security structures are in a list, we check for | |
337 | * empty list outside of the lock to make sure that we won't waste | |
338 | * time taking a lock doing nothing. | |
339 | * | |
340 | * The list_del_init() function can be safely called more than once. | |
341 | * It should not be possible for this function to be called with | |
342 | * concurrent list_add(), but for better safety against future changes | |
343 | * in the code, we use list_empty_careful() here. | |
344 | */ | |
345 | if (!list_empty_careful(&isec->list)) { | |
346 | spin_lock(&sbsec->isec_lock); | |
1da177e4 | 347 | list_del_init(&isec->list); |
9629d04a WL |
348 | spin_unlock(&sbsec->isec_lock); |
349 | } | |
1da177e4 | 350 | |
3dc91d43 SR |
351 | /* |
352 | * The inode may still be referenced in a path walk and | |
353 | * a call to selinux_inode_permission() can be made | |
354 | * after inode_free_security() is called. Ideally, the VFS | |
355 | * wouldn't do this, but fixing that is a much harder | |
356 | * job. For now, simply free the i_security via RCU, and | |
357 | * leave the current inode->i_security pointer intact. | |
358 | * The inode will be freed after the RCU grace period too. | |
359 | */ | |
360 | call_rcu(&isec->rcu, inode_free_rcu); | |
1da177e4 LT |
361 | } |
362 | ||
363 | static int file_alloc_security(struct file *file) | |
364 | { | |
1da177e4 | 365 | struct file_security_struct *fsec; |
275bb41e | 366 | u32 sid = current_sid(); |
1da177e4 | 367 | |
63205654 | 368 | fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL); |
1da177e4 LT |
369 | if (!fsec) |
370 | return -ENOMEM; | |
371 | ||
275bb41e DH |
372 | fsec->sid = sid; |
373 | fsec->fown_sid = sid; | |
1da177e4 LT |
374 | file->f_security = fsec; |
375 | ||
376 | return 0; | |
377 | } | |
378 | ||
379 | static void file_free_security(struct file *file) | |
380 | { | |
381 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 | 382 | file->f_security = NULL; |
63205654 | 383 | kmem_cache_free(file_security_cache, fsec); |
1da177e4 LT |
384 | } |
385 | ||
386 | static int superblock_alloc_security(struct super_block *sb) | |
387 | { | |
388 | struct superblock_security_struct *sbsec; | |
389 | ||
89d155ef | 390 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
391 | if (!sbsec) |
392 | return -ENOMEM; | |
393 | ||
bc7e982b | 394 | mutex_init(&sbsec->lock); |
1da177e4 LT |
395 | INIT_LIST_HEAD(&sbsec->isec_head); |
396 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
397 | sbsec->sb = sb; |
398 | sbsec->sid = SECINITSID_UNLABELED; | |
399 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 400 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
401 | sb->s_security = sbsec; |
402 | ||
403 | return 0; | |
404 | } | |
405 | ||
406 | static void superblock_free_security(struct super_block *sb) | |
407 | { | |
408 | struct superblock_security_struct *sbsec = sb->s_security; | |
1da177e4 LT |
409 | sb->s_security = NULL; |
410 | kfree(sbsec); | |
411 | } | |
412 | ||
1da177e4 LT |
413 | static inline int inode_doinit(struct inode *inode) |
414 | { | |
415 | return inode_doinit_with_dentry(inode, NULL); | |
416 | } | |
417 | ||
418 | enum { | |
31e87930 | 419 | Opt_error = -1, |
1da177e4 LT |
420 | Opt_context = 1, |
421 | Opt_fscontext = 2, | |
c9180a57 EP |
422 | Opt_defcontext = 3, |
423 | Opt_rootcontext = 4, | |
11689d47 | 424 | Opt_labelsupport = 5, |
d355987f | 425 | Opt_nextmntopt = 6, |
1da177e4 LT |
426 | }; |
427 | ||
d355987f EP |
428 | #define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) |
429 | ||
a447c093 | 430 | static const match_table_t tokens = { |
832cbd9a EP |
431 | {Opt_context, CONTEXT_STR "%s"}, |
432 | {Opt_fscontext, FSCONTEXT_STR "%s"}, | |
433 | {Opt_defcontext, DEFCONTEXT_STR "%s"}, | |
434 | {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, | |
11689d47 | 435 | {Opt_labelsupport, LABELSUPP_STR}, |
31e87930 | 436 | {Opt_error, NULL}, |
1da177e4 LT |
437 | }; |
438 | ||
439 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
440 | ||
c312feb2 EP |
441 | static int may_context_mount_sb_relabel(u32 sid, |
442 | struct superblock_security_struct *sbsec, | |
275bb41e | 443 | const struct cred *cred) |
c312feb2 | 444 | { |
275bb41e | 445 | const struct task_security_struct *tsec = cred->security; |
c312feb2 EP |
446 | int rc; |
447 | ||
448 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
449 | FILESYSTEM__RELABELFROM, NULL); | |
450 | if (rc) | |
451 | return rc; | |
452 | ||
453 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, | |
454 | FILESYSTEM__RELABELTO, NULL); | |
455 | return rc; | |
456 | } | |
457 | ||
0808925e EP |
458 | static int may_context_mount_inode_relabel(u32 sid, |
459 | struct superblock_security_struct *sbsec, | |
275bb41e | 460 | const struct cred *cred) |
0808925e | 461 | { |
275bb41e | 462 | const struct task_security_struct *tsec = cred->security; |
0808925e EP |
463 | int rc; |
464 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
465 | FILESYSTEM__RELABELFROM, NULL); | |
466 | if (rc) | |
467 | return rc; | |
468 | ||
469 | rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
470 | FILESYSTEM__ASSOCIATE, NULL); | |
471 | return rc; | |
472 | } | |
473 | ||
b43e725d EP |
474 | static int selinux_is_sblabel_mnt(struct super_block *sb) |
475 | { | |
476 | struct superblock_security_struct *sbsec = sb->s_security; | |
477 | ||
d5f3a5f6 MS |
478 | return sbsec->behavior == SECURITY_FS_USE_XATTR || |
479 | sbsec->behavior == SECURITY_FS_USE_TRANS || | |
480 | sbsec->behavior == SECURITY_FS_USE_TASK || | |
9fc2b4b4 | 481 | sbsec->behavior == SECURITY_FS_USE_NATIVE || |
d5f3a5f6 MS |
482 | /* Special handling. Genfs but also in-core setxattr handler */ |
483 | !strcmp(sb->s_type->name, "sysfs") || | |
484 | !strcmp(sb->s_type->name, "pstore") || | |
485 | !strcmp(sb->s_type->name, "debugfs") || | |
a2c7c6fb | 486 | !strcmp(sb->s_type->name, "tracefs") || |
2651225b SS |
487 | !strcmp(sb->s_type->name, "rootfs") || |
488 | (selinux_policycap_cgroupseclabel && | |
489 | (!strcmp(sb->s_type->name, "cgroup") || | |
490 | !strcmp(sb->s_type->name, "cgroup2"))); | |
b43e725d EP |
491 | } |
492 | ||
c9180a57 | 493 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 494 | { |
1da177e4 | 495 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 | 496 | struct dentry *root = sb->s_root; |
c6f493d6 | 497 | struct inode *root_inode = d_backing_inode(root); |
c9180a57 | 498 | int rc = 0; |
1da177e4 | 499 | |
c9180a57 EP |
500 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
501 | /* Make sure that the xattr handler exists and that no | |
502 | error other than -ENODATA is returned by getxattr on | |
503 | the root directory. -ENODATA is ok, as this may be | |
504 | the first boot of the SELinux kernel before we have | |
505 | assigned xattr values to the filesystem. */ | |
5d6c3191 | 506 | if (!(root_inode->i_opflags & IOP_XATTR)) { |
29b1deb2 LT |
507 | printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " |
508 | "xattr support\n", sb->s_id, sb->s_type->name); | |
c9180a57 EP |
509 | rc = -EOPNOTSUPP; |
510 | goto out; | |
511 | } | |
5d6c3191 AG |
512 | |
513 | rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); | |
c9180a57 EP |
514 | if (rc < 0 && rc != -ENODATA) { |
515 | if (rc == -EOPNOTSUPP) | |
516 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
29b1deb2 LT |
517 | "%s) has no security xattr handler\n", |
518 | sb->s_id, sb->s_type->name); | |
c9180a57 EP |
519 | else |
520 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
29b1deb2 LT |
521 | "%s) getxattr errno %d\n", sb->s_id, |
522 | sb->s_type->name, -rc); | |
c9180a57 EP |
523 | goto out; |
524 | } | |
525 | } | |
1da177e4 | 526 | |
eadcabc6 | 527 | sbsec->flags |= SE_SBINITIALIZED; |
b43e725d | 528 | if (selinux_is_sblabel_mnt(sb)) |
12f348b9 | 529 | sbsec->flags |= SBLABEL_MNT; |
ddd29ec6 | 530 | |
c9180a57 EP |
531 | /* Initialize the root inode. */ |
532 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 533 | |
c9180a57 EP |
534 | /* Initialize any other inodes associated with the superblock, e.g. |
535 | inodes created prior to initial policy load or inodes created | |
536 | during get_sb by a pseudo filesystem that directly | |
537 | populates itself. */ | |
538 | spin_lock(&sbsec->isec_lock); | |
539 | next_inode: | |
540 | if (!list_empty(&sbsec->isec_head)) { | |
541 | struct inode_security_struct *isec = | |
542 | list_entry(sbsec->isec_head.next, | |
543 | struct inode_security_struct, list); | |
544 | struct inode *inode = isec->inode; | |
923190d3 | 545 | list_del_init(&isec->list); |
c9180a57 EP |
546 | spin_unlock(&sbsec->isec_lock); |
547 | inode = igrab(inode); | |
548 | if (inode) { | |
549 | if (!IS_PRIVATE(inode)) | |
550 | inode_doinit(inode); | |
551 | iput(inode); | |
552 | } | |
553 | spin_lock(&sbsec->isec_lock); | |
c9180a57 EP |
554 | goto next_inode; |
555 | } | |
556 | spin_unlock(&sbsec->isec_lock); | |
557 | out: | |
558 | return rc; | |
559 | } | |
1da177e4 | 560 | |
c9180a57 EP |
561 | /* |
562 | * This function should allow an FS to ask what it's mount security | |
563 | * options were so it can use those later for submounts, displaying | |
564 | * mount options, or whatever. | |
565 | */ | |
566 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
e0007529 | 567 | struct security_mnt_opts *opts) |
c9180a57 EP |
568 | { |
569 | int rc = 0, i; | |
570 | struct superblock_security_struct *sbsec = sb->s_security; | |
571 | char *context = NULL; | |
572 | u32 len; | |
573 | char tmp; | |
1da177e4 | 574 | |
e0007529 | 575 | security_init_mnt_opts(opts); |
1da177e4 | 576 | |
0d90a7ec | 577 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
c9180a57 | 578 | return -EINVAL; |
1da177e4 | 579 | |
c9180a57 EP |
580 | if (!ss_initialized) |
581 | return -EINVAL; | |
1da177e4 | 582 | |
af8e50cc EP |
583 | /* make sure we always check enough bits to cover the mask */ |
584 | BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); | |
585 | ||
0d90a7ec | 586 | tmp = sbsec->flags & SE_MNTMASK; |
c9180a57 | 587 | /* count the number of mount options for this sb */ |
af8e50cc | 588 | for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { |
c9180a57 | 589 | if (tmp & 0x01) |
e0007529 | 590 | opts->num_mnt_opts++; |
c9180a57 EP |
591 | tmp >>= 1; |
592 | } | |
11689d47 | 593 | /* Check if the Label support flag is set */ |
0b4bdb35 | 594 | if (sbsec->flags & SBLABEL_MNT) |
11689d47 | 595 | opts->num_mnt_opts++; |
1da177e4 | 596 | |
e0007529 EP |
597 | opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); |
598 | if (!opts->mnt_opts) { | |
c9180a57 EP |
599 | rc = -ENOMEM; |
600 | goto out_free; | |
601 | } | |
1da177e4 | 602 | |
e0007529 EP |
603 | opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); |
604 | if (!opts->mnt_opts_flags) { | |
c9180a57 EP |
605 | rc = -ENOMEM; |
606 | goto out_free; | |
607 | } | |
1da177e4 | 608 | |
c9180a57 EP |
609 | i = 0; |
610 | if (sbsec->flags & FSCONTEXT_MNT) { | |
611 | rc = security_sid_to_context(sbsec->sid, &context, &len); | |
612 | if (rc) | |
613 | goto out_free; | |
e0007529 EP |
614 | opts->mnt_opts[i] = context; |
615 | opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; | |
c9180a57 EP |
616 | } |
617 | if (sbsec->flags & CONTEXT_MNT) { | |
618 | rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); | |
619 | if (rc) | |
620 | goto out_free; | |
e0007529 EP |
621 | opts->mnt_opts[i] = context; |
622 | opts->mnt_opts_flags[i++] = CONTEXT_MNT; | |
c9180a57 EP |
623 | } |
624 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
625 | rc = security_sid_to_context(sbsec->def_sid, &context, &len); | |
626 | if (rc) | |
627 | goto out_free; | |
e0007529 EP |
628 | opts->mnt_opts[i] = context; |
629 | opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
630 | } |
631 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
632 | struct dentry *root = sbsec->sb->s_root; |
633 | struct inode_security_struct *isec = backing_inode_security(root); | |
0808925e | 634 | |
c9180a57 EP |
635 | rc = security_sid_to_context(isec->sid, &context, &len); |
636 | if (rc) | |
637 | goto out_free; | |
e0007529 EP |
638 | opts->mnt_opts[i] = context; |
639 | opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; | |
c9180a57 | 640 | } |
12f348b9 | 641 | if (sbsec->flags & SBLABEL_MNT) { |
11689d47 | 642 | opts->mnt_opts[i] = NULL; |
12f348b9 | 643 | opts->mnt_opts_flags[i++] = SBLABEL_MNT; |
11689d47 | 644 | } |
1da177e4 | 645 | |
e0007529 | 646 | BUG_ON(i != opts->num_mnt_opts); |
1da177e4 | 647 | |
c9180a57 EP |
648 | return 0; |
649 | ||
650 | out_free: | |
e0007529 | 651 | security_free_mnt_opts(opts); |
c9180a57 EP |
652 | return rc; |
653 | } | |
1da177e4 | 654 | |
c9180a57 EP |
655 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
656 | u32 old_sid, u32 new_sid) | |
657 | { | |
0d90a7ec DQ |
658 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
659 | ||
c9180a57 | 660 | /* check if the old mount command had the same options */ |
0d90a7ec | 661 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
662 | if (!(sbsec->flags & flag) || |
663 | (old_sid != new_sid)) | |
664 | return 1; | |
665 | ||
666 | /* check if we were passed the same options twice, | |
667 | * aka someone passed context=a,context=b | |
668 | */ | |
0d90a7ec DQ |
669 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
670 | if (mnt_flags & flag) | |
c9180a57 EP |
671 | return 1; |
672 | return 0; | |
673 | } | |
e0007529 | 674 | |
c9180a57 EP |
675 | /* |
676 | * Allow filesystems with binary mount data to explicitly set mount point | |
677 | * labeling information. | |
678 | */ | |
e0007529 | 679 | static int selinux_set_mnt_opts(struct super_block *sb, |
649f6e77 DQ |
680 | struct security_mnt_opts *opts, |
681 | unsigned long kern_flags, | |
682 | unsigned long *set_kern_flags) | |
c9180a57 | 683 | { |
275bb41e | 684 | const struct cred *cred = current_cred(); |
c9180a57 | 685 | int rc = 0, i; |
c9180a57 | 686 | struct superblock_security_struct *sbsec = sb->s_security; |
29b1deb2 | 687 | const char *name = sb->s_type->name; |
83da53c5 | 688 | struct dentry *root = sbsec->sb->s_root; |
2c97165b | 689 | struct inode_security_struct *root_isec; |
c9180a57 EP |
690 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
691 | u32 defcontext_sid = 0; | |
e0007529 EP |
692 | char **mount_options = opts->mnt_opts; |
693 | int *flags = opts->mnt_opts_flags; | |
694 | int num_opts = opts->num_mnt_opts; | |
c9180a57 EP |
695 | |
696 | mutex_lock(&sbsec->lock); | |
697 | ||
698 | if (!ss_initialized) { | |
699 | if (!num_opts) { | |
700 | /* Defer initialization until selinux_complete_init, | |
701 | after the initial policy is loaded and the security | |
702 | server is ready to handle calls. */ | |
c9180a57 EP |
703 | goto out; |
704 | } | |
705 | rc = -EINVAL; | |
744ba35e EP |
706 | printk(KERN_WARNING "SELinux: Unable to set superblock options " |
707 | "before the security server is initialized\n"); | |
1da177e4 | 708 | goto out; |
c9180a57 | 709 | } |
649f6e77 DQ |
710 | if (kern_flags && !set_kern_flags) { |
711 | /* Specifying internal flags without providing a place to | |
712 | * place the results is not allowed */ | |
713 | rc = -EINVAL; | |
714 | goto out; | |
715 | } | |
1da177e4 | 716 | |
e0007529 EP |
717 | /* |
718 | * Binary mount data FS will come through this function twice. Once | |
719 | * from an explicit call and once from the generic calls from the vfs. | |
720 | * Since the generic VFS calls will not contain any security mount data | |
721 | * we need to skip the double mount verification. | |
722 | * | |
723 | * This does open a hole in which we will not notice if the first | |
724 | * mount using this sb set explict options and a second mount using | |
725 | * this sb does not set any security options. (The first options | |
726 | * will be used for both mounts) | |
727 | */ | |
0d90a7ec | 728 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
e0007529 | 729 | && (num_opts == 0)) |
f5269710 | 730 | goto out; |
e0007529 | 731 | |
2c97165b PM |
732 | root_isec = backing_inode_security_novalidate(root); |
733 | ||
c9180a57 EP |
734 | /* |
735 | * parse the mount options, check if they are valid sids. | |
736 | * also check if someone is trying to mount the same sb more | |
737 | * than once with different security options. | |
738 | */ | |
739 | for (i = 0; i < num_opts; i++) { | |
740 | u32 sid; | |
11689d47 | 741 | |
12f348b9 | 742 | if (flags[i] == SBLABEL_MNT) |
11689d47 | 743 | continue; |
44be2f65 | 744 | rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL); |
1da177e4 | 745 | if (rc) { |
44be2f65 | 746 | printk(KERN_WARNING "SELinux: security_context_str_to_sid" |
29b1deb2 LT |
747 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
748 | mount_options[i], sb->s_id, name, rc); | |
c9180a57 EP |
749 | goto out; |
750 | } | |
751 | switch (flags[i]) { | |
752 | case FSCONTEXT_MNT: | |
753 | fscontext_sid = sid; | |
754 | ||
755 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
756 | fscontext_sid)) | |
757 | goto out_double_mount; | |
758 | ||
759 | sbsec->flags |= FSCONTEXT_MNT; | |
760 | break; | |
761 | case CONTEXT_MNT: | |
762 | context_sid = sid; | |
763 | ||
764 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
765 | context_sid)) | |
766 | goto out_double_mount; | |
767 | ||
768 | sbsec->flags |= CONTEXT_MNT; | |
769 | break; | |
770 | case ROOTCONTEXT_MNT: | |
771 | rootcontext_sid = sid; | |
772 | ||
773 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
774 | rootcontext_sid)) | |
775 | goto out_double_mount; | |
776 | ||
777 | sbsec->flags |= ROOTCONTEXT_MNT; | |
778 | ||
779 | break; | |
780 | case DEFCONTEXT_MNT: | |
781 | defcontext_sid = sid; | |
782 | ||
783 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
784 | defcontext_sid)) | |
785 | goto out_double_mount; | |
786 | ||
787 | sbsec->flags |= DEFCONTEXT_MNT; | |
788 | ||
789 | break; | |
790 | default: | |
791 | rc = -EINVAL; | |
792 | goto out; | |
1da177e4 | 793 | } |
c9180a57 EP |
794 | } |
795 | ||
0d90a7ec | 796 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 797 | /* previously mounted with options, but not on this attempt? */ |
0d90a7ec | 798 | if ((sbsec->flags & SE_MNTMASK) && !num_opts) |
c9180a57 EP |
799 | goto out_double_mount; |
800 | rc = 0; | |
801 | goto out; | |
802 | } | |
803 | ||
089be43e | 804 | if (strcmp(sb->s_type->name, "proc") == 0) |
134509d5 SS |
805 | sbsec->flags |= SE_SBPROC | SE_SBGENFS; |
806 | ||
8e014720 SS |
807 | if (!strcmp(sb->s_type->name, "debugfs") || |
808 | !strcmp(sb->s_type->name, "sysfs") || | |
809 | !strcmp(sb->s_type->name, "pstore")) | |
134509d5 | 810 | sbsec->flags |= SE_SBGENFS; |
c9180a57 | 811 | |
eb9ae686 DQ |
812 | if (!sbsec->behavior) { |
813 | /* | |
814 | * Determine the labeling behavior to use for this | |
815 | * filesystem type. | |
816 | */ | |
98f700f3 | 817 | rc = security_fs_use(sb); |
eb9ae686 DQ |
818 | if (rc) { |
819 | printk(KERN_WARNING | |
820 | "%s: security_fs_use(%s) returned %d\n", | |
821 | __func__, sb->s_type->name, rc); | |
822 | goto out; | |
823 | } | |
c9180a57 | 824 | } |
aad82892 SF |
825 | |
826 | /* | |
01593d32 SS |
827 | * If this is a user namespace mount and the filesystem type is not |
828 | * explicitly whitelisted, then no contexts are allowed on the command | |
829 | * line and security labels must be ignored. | |
aad82892 | 830 | */ |
01593d32 SS |
831 | if (sb->s_user_ns != &init_user_ns && |
832 | strcmp(sb->s_type->name, "tmpfs") && | |
833 | strcmp(sb->s_type->name, "ramfs") && | |
834 | strcmp(sb->s_type->name, "devpts")) { | |
aad82892 SF |
835 | if (context_sid || fscontext_sid || rootcontext_sid || |
836 | defcontext_sid) { | |
837 | rc = -EACCES; | |
838 | goto out; | |
839 | } | |
840 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { | |
841 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; | |
842 | rc = security_transition_sid(current_sid(), current_sid(), | |
843 | SECCLASS_FILE, NULL, | |
844 | &sbsec->mntpoint_sid); | |
845 | if (rc) | |
846 | goto out; | |
847 | } | |
848 | goto out_set_opts; | |
849 | } | |
850 | ||
c9180a57 EP |
851 | /* sets the context of the superblock for the fs being mounted. */ |
852 | if (fscontext_sid) { | |
275bb41e | 853 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
1da177e4 | 854 | if (rc) |
c9180a57 | 855 | goto out; |
1da177e4 | 856 | |
c9180a57 | 857 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
858 | } |
859 | ||
860 | /* | |
861 | * Switch to using mount point labeling behavior. | |
862 | * sets the label used on all file below the mountpoint, and will set | |
863 | * the superblock context if not already set. | |
864 | */ | |
eb9ae686 DQ |
865 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { |
866 | sbsec->behavior = SECURITY_FS_USE_NATIVE; | |
867 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
868 | } | |
869 | ||
c9180a57 EP |
870 | if (context_sid) { |
871 | if (!fscontext_sid) { | |
275bb41e DH |
872 | rc = may_context_mount_sb_relabel(context_sid, sbsec, |
873 | cred); | |
b04ea3ce | 874 | if (rc) |
c9180a57 EP |
875 | goto out; |
876 | sbsec->sid = context_sid; | |
b04ea3ce | 877 | } else { |
275bb41e DH |
878 | rc = may_context_mount_inode_relabel(context_sid, sbsec, |
879 | cred); | |
b04ea3ce | 880 | if (rc) |
c9180a57 | 881 | goto out; |
b04ea3ce | 882 | } |
c9180a57 EP |
883 | if (!rootcontext_sid) |
884 | rootcontext_sid = context_sid; | |
1da177e4 | 885 | |
c9180a57 | 886 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 887 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
888 | } |
889 | ||
c9180a57 | 890 | if (rootcontext_sid) { |
275bb41e DH |
891 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
892 | cred); | |
0808925e | 893 | if (rc) |
c9180a57 | 894 | goto out; |
0808925e | 895 | |
c9180a57 | 896 | root_isec->sid = rootcontext_sid; |
6f3be9f5 | 897 | root_isec->initialized = LABEL_INITIALIZED; |
0808925e EP |
898 | } |
899 | ||
c9180a57 | 900 | if (defcontext_sid) { |
eb9ae686 DQ |
901 | if (sbsec->behavior != SECURITY_FS_USE_XATTR && |
902 | sbsec->behavior != SECURITY_FS_USE_NATIVE) { | |
c9180a57 EP |
903 | rc = -EINVAL; |
904 | printk(KERN_WARNING "SELinux: defcontext option is " | |
905 | "invalid for this filesystem type\n"); | |
906 | goto out; | |
1da177e4 LT |
907 | } |
908 | ||
c9180a57 EP |
909 | if (defcontext_sid != sbsec->def_sid) { |
910 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
275bb41e | 911 | sbsec, cred); |
c9180a57 EP |
912 | if (rc) |
913 | goto out; | |
914 | } | |
1da177e4 | 915 | |
c9180a57 | 916 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
917 | } |
918 | ||
aad82892 | 919 | out_set_opts: |
c9180a57 | 920 | rc = sb_finish_set_opts(sb); |
1da177e4 | 921 | out: |
c9180a57 | 922 | mutex_unlock(&sbsec->lock); |
1da177e4 | 923 | return rc; |
c9180a57 EP |
924 | out_double_mount: |
925 | rc = -EINVAL; | |
926 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " | |
29b1deb2 | 927 | "security settings for (dev %s, type %s)\n", sb->s_id, name); |
c9180a57 | 928 | goto out; |
1da177e4 LT |
929 | } |
930 | ||
094f7b69 JL |
931 | static int selinux_cmp_sb_context(const struct super_block *oldsb, |
932 | const struct super_block *newsb) | |
933 | { | |
934 | struct superblock_security_struct *old = oldsb->s_security; | |
935 | struct superblock_security_struct *new = newsb->s_security; | |
936 | char oldflags = old->flags & SE_MNTMASK; | |
937 | char newflags = new->flags & SE_MNTMASK; | |
938 | ||
939 | if (oldflags != newflags) | |
940 | goto mismatch; | |
941 | if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) | |
942 | goto mismatch; | |
943 | if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) | |
944 | goto mismatch; | |
945 | if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) | |
946 | goto mismatch; | |
947 | if (oldflags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
948 | struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); |
949 | struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); | |
094f7b69 JL |
950 | if (oldroot->sid != newroot->sid) |
951 | goto mismatch; | |
952 | } | |
953 | return 0; | |
954 | mismatch: | |
955 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " | |
956 | "different security settings for (dev %s, " | |
957 | "type %s)\n", newsb->s_id, newsb->s_type->name); | |
958 | return -EBUSY; | |
959 | } | |
960 | ||
961 | static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, | |
c9180a57 | 962 | struct super_block *newsb) |
1da177e4 | 963 | { |
c9180a57 EP |
964 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
965 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 966 | |
c9180a57 EP |
967 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
968 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
969 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 970 | |
0f5e6420 EP |
971 | /* |
972 | * if the parent was able to be mounted it clearly had no special lsm | |
e8c26255 | 973 | * mount options. thus we can safely deal with this superblock later |
0f5e6420 | 974 | */ |
e8c26255 | 975 | if (!ss_initialized) |
094f7b69 | 976 | return 0; |
c9180a57 | 977 | |
c9180a57 | 978 | /* how can we clone if the old one wasn't set up?? */ |
0d90a7ec | 979 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
c9180a57 | 980 | |
094f7b69 | 981 | /* if fs is reusing a sb, make sure that the contexts match */ |
0d90a7ec | 982 | if (newsbsec->flags & SE_SBINITIALIZED) |
094f7b69 | 983 | return selinux_cmp_sb_context(oldsb, newsb); |
5a552617 | 984 | |
c9180a57 EP |
985 | mutex_lock(&newsbsec->lock); |
986 | ||
987 | newsbsec->flags = oldsbsec->flags; | |
988 | ||
989 | newsbsec->sid = oldsbsec->sid; | |
990 | newsbsec->def_sid = oldsbsec->def_sid; | |
991 | newsbsec->behavior = oldsbsec->behavior; | |
992 | ||
993 | if (set_context) { | |
994 | u32 sid = oldsbsec->mntpoint_sid; | |
995 | ||
996 | if (!set_fscontext) | |
997 | newsbsec->sid = sid; | |
998 | if (!set_rootcontext) { | |
83da53c5 | 999 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); |
c9180a57 EP |
1000 | newisec->sid = sid; |
1001 | } | |
1002 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 1003 | } |
c9180a57 | 1004 | if (set_rootcontext) { |
83da53c5 AG |
1005 | const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); |
1006 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); | |
1da177e4 | 1007 | |
c9180a57 | 1008 | newisec->sid = oldisec->sid; |
1da177e4 LT |
1009 | } |
1010 | ||
c9180a57 EP |
1011 | sb_finish_set_opts(newsb); |
1012 | mutex_unlock(&newsbsec->lock); | |
094f7b69 | 1013 | return 0; |
c9180a57 EP |
1014 | } |
1015 | ||
2e1479d9 AB |
1016 | static int selinux_parse_opts_str(char *options, |
1017 | struct security_mnt_opts *opts) | |
c9180a57 | 1018 | { |
e0007529 | 1019 | char *p; |
c9180a57 EP |
1020 | char *context = NULL, *defcontext = NULL; |
1021 | char *fscontext = NULL, *rootcontext = NULL; | |
e0007529 | 1022 | int rc, num_mnt_opts = 0; |
1da177e4 | 1023 | |
e0007529 | 1024 | opts->num_mnt_opts = 0; |
1da177e4 | 1025 | |
c9180a57 EP |
1026 | /* Standard string-based options. */ |
1027 | while ((p = strsep(&options, "|")) != NULL) { | |
1028 | int token; | |
1029 | substring_t args[MAX_OPT_ARGS]; | |
1da177e4 | 1030 | |
c9180a57 EP |
1031 | if (!*p) |
1032 | continue; | |
1da177e4 | 1033 | |
c9180a57 | 1034 | token = match_token(p, tokens, args); |
1da177e4 | 1035 | |
c9180a57 EP |
1036 | switch (token) { |
1037 | case Opt_context: | |
1038 | if (context || defcontext) { | |
1039 | rc = -EINVAL; | |
1040 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1041 | goto out_err; | |
1042 | } | |
1043 | context = match_strdup(&args[0]); | |
1044 | if (!context) { | |
1045 | rc = -ENOMEM; | |
1046 | goto out_err; | |
1047 | } | |
1048 | break; | |
1049 | ||
1050 | case Opt_fscontext: | |
1051 | if (fscontext) { | |
1052 | rc = -EINVAL; | |
1053 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1054 | goto out_err; | |
1055 | } | |
1056 | fscontext = match_strdup(&args[0]); | |
1057 | if (!fscontext) { | |
1058 | rc = -ENOMEM; | |
1059 | goto out_err; | |
1060 | } | |
1061 | break; | |
1062 | ||
1063 | case Opt_rootcontext: | |
1064 | if (rootcontext) { | |
1065 | rc = -EINVAL; | |
1066 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1067 | goto out_err; | |
1068 | } | |
1069 | rootcontext = match_strdup(&args[0]); | |
1070 | if (!rootcontext) { | |
1071 | rc = -ENOMEM; | |
1072 | goto out_err; | |
1073 | } | |
1074 | break; | |
1075 | ||
1076 | case Opt_defcontext: | |
1077 | if (context || defcontext) { | |
1078 | rc = -EINVAL; | |
1079 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1080 | goto out_err; | |
1081 | } | |
1082 | defcontext = match_strdup(&args[0]); | |
1083 | if (!defcontext) { | |
1084 | rc = -ENOMEM; | |
1085 | goto out_err; | |
1086 | } | |
1087 | break; | |
11689d47 DQ |
1088 | case Opt_labelsupport: |
1089 | break; | |
c9180a57 EP |
1090 | default: |
1091 | rc = -EINVAL; | |
1092 | printk(KERN_WARNING "SELinux: unknown mount option\n"); | |
1093 | goto out_err; | |
1da177e4 | 1094 | |
1da177e4 | 1095 | } |
1da177e4 | 1096 | } |
c9180a57 | 1097 | |
e0007529 | 1098 | rc = -ENOMEM; |
8931c3bd | 1099 | opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL); |
e0007529 EP |
1100 | if (!opts->mnt_opts) |
1101 | goto out_err; | |
1102 | ||
8931c3bd TH |
1103 | opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), |
1104 | GFP_KERNEL); | |
e0007529 EP |
1105 | if (!opts->mnt_opts_flags) { |
1106 | kfree(opts->mnt_opts); | |
1107 | goto out_err; | |
1108 | } | |
1109 | ||
c9180a57 | 1110 | if (fscontext) { |
e0007529 EP |
1111 | opts->mnt_opts[num_mnt_opts] = fscontext; |
1112 | opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; | |
c9180a57 EP |
1113 | } |
1114 | if (context) { | |
e0007529 EP |
1115 | opts->mnt_opts[num_mnt_opts] = context; |
1116 | opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; | |
c9180a57 EP |
1117 | } |
1118 | if (rootcontext) { | |
e0007529 EP |
1119 | opts->mnt_opts[num_mnt_opts] = rootcontext; |
1120 | opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; | |
c9180a57 EP |
1121 | } |
1122 | if (defcontext) { | |
e0007529 EP |
1123 | opts->mnt_opts[num_mnt_opts] = defcontext; |
1124 | opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
1125 | } |
1126 | ||
e0007529 EP |
1127 | opts->num_mnt_opts = num_mnt_opts; |
1128 | return 0; | |
1129 | ||
c9180a57 EP |
1130 | out_err: |
1131 | kfree(context); | |
1132 | kfree(defcontext); | |
1133 | kfree(fscontext); | |
1134 | kfree(rootcontext); | |
1da177e4 LT |
1135 | return rc; |
1136 | } | |
e0007529 EP |
1137 | /* |
1138 | * string mount options parsing and call set the sbsec | |
1139 | */ | |
1140 | static int superblock_doinit(struct super_block *sb, void *data) | |
1141 | { | |
1142 | int rc = 0; | |
1143 | char *options = data; | |
1144 | struct security_mnt_opts opts; | |
1145 | ||
1146 | security_init_mnt_opts(&opts); | |
1147 | ||
1148 | if (!data) | |
1149 | goto out; | |
1150 | ||
1151 | BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); | |
1152 | ||
1153 | rc = selinux_parse_opts_str(options, &opts); | |
1154 | if (rc) | |
1155 | goto out_err; | |
1156 | ||
1157 | out: | |
649f6e77 | 1158 | rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); |
e0007529 EP |
1159 | |
1160 | out_err: | |
1161 | security_free_mnt_opts(&opts); | |
1162 | return rc; | |
1163 | } | |
1da177e4 | 1164 | |
3583a711 AB |
1165 | static void selinux_write_opts(struct seq_file *m, |
1166 | struct security_mnt_opts *opts) | |
2069f457 EP |
1167 | { |
1168 | int i; | |
1169 | char *prefix; | |
1170 | ||
1171 | for (i = 0; i < opts->num_mnt_opts; i++) { | |
11689d47 DQ |
1172 | char *has_comma; |
1173 | ||
1174 | if (opts->mnt_opts[i]) | |
1175 | has_comma = strchr(opts->mnt_opts[i], ','); | |
1176 | else | |
1177 | has_comma = NULL; | |
2069f457 EP |
1178 | |
1179 | switch (opts->mnt_opts_flags[i]) { | |
1180 | case CONTEXT_MNT: | |
1181 | prefix = CONTEXT_STR; | |
1182 | break; | |
1183 | case FSCONTEXT_MNT: | |
1184 | prefix = FSCONTEXT_STR; | |
1185 | break; | |
1186 | case ROOTCONTEXT_MNT: | |
1187 | prefix = ROOTCONTEXT_STR; | |
1188 | break; | |
1189 | case DEFCONTEXT_MNT: | |
1190 | prefix = DEFCONTEXT_STR; | |
1191 | break; | |
12f348b9 | 1192 | case SBLABEL_MNT: |
11689d47 DQ |
1193 | seq_putc(m, ','); |
1194 | seq_puts(m, LABELSUPP_STR); | |
1195 | continue; | |
2069f457 EP |
1196 | default: |
1197 | BUG(); | |
a35c6c83 | 1198 | return; |
2069f457 EP |
1199 | }; |
1200 | /* we need a comma before each option */ | |
1201 | seq_putc(m, ','); | |
1202 | seq_puts(m, prefix); | |
1203 | if (has_comma) | |
1204 | seq_putc(m, '\"'); | |
a068acf2 | 1205 | seq_escape(m, opts->mnt_opts[i], "\"\n\\"); |
2069f457 EP |
1206 | if (has_comma) |
1207 | seq_putc(m, '\"'); | |
1208 | } | |
1209 | } | |
1210 | ||
1211 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1212 | { | |
1213 | struct security_mnt_opts opts; | |
1214 | int rc; | |
1215 | ||
1216 | rc = selinux_get_mnt_opts(sb, &opts); | |
383795c2 EP |
1217 | if (rc) { |
1218 | /* before policy load we may get EINVAL, don't show anything */ | |
1219 | if (rc == -EINVAL) | |
1220 | rc = 0; | |
2069f457 | 1221 | return rc; |
383795c2 | 1222 | } |
2069f457 EP |
1223 | |
1224 | selinux_write_opts(m, &opts); | |
1225 | ||
1226 | security_free_mnt_opts(&opts); | |
1227 | ||
1228 | return rc; | |
1229 | } | |
1230 | ||
1da177e4 LT |
1231 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1232 | { | |
1233 | switch (mode & S_IFMT) { | |
1234 | case S_IFSOCK: | |
1235 | return SECCLASS_SOCK_FILE; | |
1236 | case S_IFLNK: | |
1237 | return SECCLASS_LNK_FILE; | |
1238 | case S_IFREG: | |
1239 | return SECCLASS_FILE; | |
1240 | case S_IFBLK: | |
1241 | return SECCLASS_BLK_FILE; | |
1242 | case S_IFDIR: | |
1243 | return SECCLASS_DIR; | |
1244 | case S_IFCHR: | |
1245 | return SECCLASS_CHR_FILE; | |
1246 | case S_IFIFO: | |
1247 | return SECCLASS_FIFO_FILE; | |
1248 | ||
1249 | } | |
1250 | ||
1251 | return SECCLASS_FILE; | |
1252 | } | |
1253 | ||
13402580 JM |
1254 | static inline int default_protocol_stream(int protocol) |
1255 | { | |
1256 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1257 | } | |
1258 | ||
1259 | static inline int default_protocol_dgram(int protocol) | |
1260 | { | |
1261 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1262 | } | |
1263 | ||
1da177e4 LT |
1264 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1265 | { | |
da69a530 SS |
1266 | int extsockclass = selinux_policycap_extsockclass; |
1267 | ||
1da177e4 LT |
1268 | switch (family) { |
1269 | case PF_UNIX: | |
1270 | switch (type) { | |
1271 | case SOCK_STREAM: | |
1272 | case SOCK_SEQPACKET: | |
1273 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1274 | case SOCK_DGRAM: | |
1275 | return SECCLASS_UNIX_DGRAM_SOCKET; | |
1276 | } | |
1277 | break; | |
1278 | case PF_INET: | |
1279 | case PF_INET6: | |
1280 | switch (type) { | |
1281 | case SOCK_STREAM: | |
da69a530 | 1282 | case SOCK_SEQPACKET: |
13402580 JM |
1283 | if (default_protocol_stream(protocol)) |
1284 | return SECCLASS_TCP_SOCKET; | |
da69a530 SS |
1285 | else if (extsockclass && protocol == IPPROTO_SCTP) |
1286 | return SECCLASS_SCTP_SOCKET; | |
13402580 JM |
1287 | else |
1288 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1289 | case SOCK_DGRAM: |
13402580 JM |
1290 | if (default_protocol_dgram(protocol)) |
1291 | return SECCLASS_UDP_SOCKET; | |
ef37979a SS |
1292 | else if (extsockclass && (protocol == IPPROTO_ICMP || |
1293 | protocol == IPPROTO_ICMPV6)) | |
da69a530 | 1294 | return SECCLASS_ICMP_SOCKET; |
13402580 JM |
1295 | else |
1296 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1297 | case SOCK_DCCP: |
1298 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1299 | default: |
1da177e4 LT |
1300 | return SECCLASS_RAWIP_SOCKET; |
1301 | } | |
1302 | break; | |
1303 | case PF_NETLINK: | |
1304 | switch (protocol) { | |
1305 | case NETLINK_ROUTE: | |
1306 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
7f1fb60c | 1307 | case NETLINK_SOCK_DIAG: |
1da177e4 LT |
1308 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1309 | case NETLINK_NFLOG: | |
1310 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1311 | case NETLINK_XFRM: | |
1312 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1313 | case NETLINK_SELINUX: | |
1314 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
6c6d2e9b SS |
1315 | case NETLINK_ISCSI: |
1316 | return SECCLASS_NETLINK_ISCSI_SOCKET; | |
1da177e4 LT |
1317 | case NETLINK_AUDIT: |
1318 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
6c6d2e9b SS |
1319 | case NETLINK_FIB_LOOKUP: |
1320 | return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; | |
1321 | case NETLINK_CONNECTOR: | |
1322 | return SECCLASS_NETLINK_CONNECTOR_SOCKET; | |
1323 | case NETLINK_NETFILTER: | |
1324 | return SECCLASS_NETLINK_NETFILTER_SOCKET; | |
1da177e4 LT |
1325 | case NETLINK_DNRTMSG: |
1326 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1327 | case NETLINK_KOBJECT_UEVENT: |
1328 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
6c6d2e9b SS |
1329 | case NETLINK_GENERIC: |
1330 | return SECCLASS_NETLINK_GENERIC_SOCKET; | |
1331 | case NETLINK_SCSITRANSPORT: | |
1332 | return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; | |
1333 | case NETLINK_RDMA: | |
1334 | return SECCLASS_NETLINK_RDMA_SOCKET; | |
1335 | case NETLINK_CRYPTO: | |
1336 | return SECCLASS_NETLINK_CRYPTO_SOCKET; | |
1da177e4 LT |
1337 | default: |
1338 | return SECCLASS_NETLINK_SOCKET; | |
1339 | } | |
1340 | case PF_PACKET: | |
1341 | return SECCLASS_PACKET_SOCKET; | |
1342 | case PF_KEY: | |
1343 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1344 | case PF_APPLETALK: |
1345 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1346 | } |
1347 | ||
da69a530 SS |
1348 | if (extsockclass) { |
1349 | switch (family) { | |
1350 | case PF_AX25: | |
1351 | return SECCLASS_AX25_SOCKET; | |
1352 | case PF_IPX: | |
1353 | return SECCLASS_IPX_SOCKET; | |
1354 | case PF_NETROM: | |
1355 | return SECCLASS_NETROM_SOCKET; | |
da69a530 SS |
1356 | case PF_ATMPVC: |
1357 | return SECCLASS_ATMPVC_SOCKET; | |
1358 | case PF_X25: | |
1359 | return SECCLASS_X25_SOCKET; | |
1360 | case PF_ROSE: | |
1361 | return SECCLASS_ROSE_SOCKET; | |
1362 | case PF_DECnet: | |
1363 | return SECCLASS_DECNET_SOCKET; | |
1364 | case PF_ATMSVC: | |
1365 | return SECCLASS_ATMSVC_SOCKET; | |
1366 | case PF_RDS: | |
1367 | return SECCLASS_RDS_SOCKET; | |
1368 | case PF_IRDA: | |
1369 | return SECCLASS_IRDA_SOCKET; | |
1370 | case PF_PPPOX: | |
1371 | return SECCLASS_PPPOX_SOCKET; | |
1372 | case PF_LLC: | |
1373 | return SECCLASS_LLC_SOCKET; | |
da69a530 SS |
1374 | case PF_CAN: |
1375 | return SECCLASS_CAN_SOCKET; | |
1376 | case PF_TIPC: | |
1377 | return SECCLASS_TIPC_SOCKET; | |
1378 | case PF_BLUETOOTH: | |
1379 | return SECCLASS_BLUETOOTH_SOCKET; | |
1380 | case PF_IUCV: | |
1381 | return SECCLASS_IUCV_SOCKET; | |
1382 | case PF_RXRPC: | |
1383 | return SECCLASS_RXRPC_SOCKET; | |
1384 | case PF_ISDN: | |
1385 | return SECCLASS_ISDN_SOCKET; | |
1386 | case PF_PHONET: | |
1387 | return SECCLASS_PHONET_SOCKET; | |
1388 | case PF_IEEE802154: | |
1389 | return SECCLASS_IEEE802154_SOCKET; | |
1390 | case PF_CAIF: | |
1391 | return SECCLASS_CAIF_SOCKET; | |
1392 | case PF_ALG: | |
1393 | return SECCLASS_ALG_SOCKET; | |
1394 | case PF_NFC: | |
1395 | return SECCLASS_NFC_SOCKET; | |
1396 | case PF_VSOCK: | |
1397 | return SECCLASS_VSOCK_SOCKET; | |
1398 | case PF_KCM: | |
1399 | return SECCLASS_KCM_SOCKET; | |
1400 | case PF_QIPCRTR: | |
1401 | return SECCLASS_QIPCRTR_SOCKET; | |
3051bf36 LT |
1402 | case PF_SMC: |
1403 | return SECCLASS_SMC_SOCKET; | |
1404 | #if PF_MAX > 44 | |
da69a530 SS |
1405 | #error New address family defined, please update this function. |
1406 | #endif | |
1407 | } | |
1408 | } | |
1409 | ||
1da177e4 LT |
1410 | return SECCLASS_SOCKET; |
1411 | } | |
1412 | ||
134509d5 SS |
1413 | static int selinux_genfs_get_sid(struct dentry *dentry, |
1414 | u16 tclass, | |
1415 | u16 flags, | |
1416 | u32 *sid) | |
1da177e4 | 1417 | { |
8e6c9693 | 1418 | int rc; |
fc64005c | 1419 | struct super_block *sb = dentry->d_sb; |
8e6c9693 | 1420 | char *buffer, *path; |
1da177e4 | 1421 | |
828dfe1d | 1422 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1423 | if (!buffer) |
1424 | return -ENOMEM; | |
1425 | ||
8e6c9693 LAG |
1426 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1427 | if (IS_ERR(path)) | |
1428 | rc = PTR_ERR(path); | |
1429 | else { | |
134509d5 SS |
1430 | if (flags & SE_SBPROC) { |
1431 | /* each process gets a /proc/PID/ entry. Strip off the | |
1432 | * PID part to get a valid selinux labeling. | |
1433 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1434 | while (path[1] >= '0' && path[1] <= '9') { | |
1435 | path[1] = '/'; | |
1436 | path++; | |
1437 | } | |
8e6c9693 | 1438 | } |
134509d5 | 1439 | rc = security_genfs_sid(sb->s_type->name, path, tclass, sid); |
1da177e4 | 1440 | } |
1da177e4 LT |
1441 | free_page((unsigned long)buffer); |
1442 | return rc; | |
1443 | } | |
1da177e4 LT |
1444 | |
1445 | /* The inode's security attributes must be initialized before first use. */ | |
1446 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1447 | { | |
1448 | struct superblock_security_struct *sbsec = NULL; | |
1449 | struct inode_security_struct *isec = inode->i_security; | |
9287aed2 AG |
1450 | u32 task_sid, sid = 0; |
1451 | u16 sclass; | |
1da177e4 LT |
1452 | struct dentry *dentry; |
1453 | #define INITCONTEXTLEN 255 | |
1454 | char *context = NULL; | |
1455 | unsigned len = 0; | |
1456 | int rc = 0; | |
1da177e4 | 1457 | |
6f3be9f5 | 1458 | if (isec->initialized == LABEL_INITIALIZED) |
13457d07 | 1459 | return 0; |
1da177e4 | 1460 | |
9287aed2 | 1461 | spin_lock(&isec->lock); |
6f3be9f5 | 1462 | if (isec->initialized == LABEL_INITIALIZED) |
23970741 | 1463 | goto out_unlock; |
1da177e4 | 1464 | |
13457d07 AG |
1465 | if (isec->sclass == SECCLASS_FILE) |
1466 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1467 | ||
1da177e4 | 1468 | sbsec = inode->i_sb->s_security; |
0d90a7ec | 1469 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1470 | /* Defer initialization until selinux_complete_init, |
1471 | after the initial policy is loaded and the security | |
1472 | server is ready to handle calls. */ | |
1473 | spin_lock(&sbsec->isec_lock); | |
1474 | if (list_empty(&isec->list)) | |
1475 | list_add(&isec->list, &sbsec->isec_head); | |
1476 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1477 | goto out_unlock; |
1da177e4 LT |
1478 | } |
1479 | ||
9287aed2 AG |
1480 | sclass = isec->sclass; |
1481 | task_sid = isec->task_sid; | |
1482 | sid = isec->sid; | |
1483 | isec->initialized = LABEL_PENDING; | |
1484 | spin_unlock(&isec->lock); | |
1485 | ||
1da177e4 | 1486 | switch (sbsec->behavior) { |
eb9ae686 DQ |
1487 | case SECURITY_FS_USE_NATIVE: |
1488 | break; | |
1da177e4 | 1489 | case SECURITY_FS_USE_XATTR: |
5d6c3191 | 1490 | if (!(inode->i_opflags & IOP_XATTR)) { |
9287aed2 | 1491 | sid = sbsec->def_sid; |
1da177e4 LT |
1492 | break; |
1493 | } | |
1da177e4 LT |
1494 | /* Need a dentry, since the xattr API requires one. |
1495 | Life would be simpler if we could just pass the inode. */ | |
1496 | if (opt_dentry) { | |
1497 | /* Called from d_instantiate or d_splice_alias. */ | |
1498 | dentry = dget(opt_dentry); | |
1499 | } else { | |
1500 | /* Called from selinux_complete_init, try to find a dentry. */ | |
1501 | dentry = d_find_alias(inode); | |
1502 | } | |
1503 | if (!dentry) { | |
df7f54c0 EP |
1504 | /* |
1505 | * this is can be hit on boot when a file is accessed | |
1506 | * before the policy is loaded. When we load policy we | |
1507 | * may find inodes that have no dentry on the | |
1508 | * sbsec->isec_head list. No reason to complain as these | |
1509 | * will get fixed up the next time we go through | |
1510 | * inode_doinit with a dentry, before these inodes could | |
1511 | * be used again by userspace. | |
1512 | */ | |
9287aed2 | 1513 | goto out; |
1da177e4 LT |
1514 | } |
1515 | ||
1516 | len = INITCONTEXTLEN; | |
4cb912f1 | 1517 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1518 | if (!context) { |
1519 | rc = -ENOMEM; | |
1520 | dput(dentry); | |
9287aed2 | 1521 | goto out; |
1da177e4 | 1522 | } |
4cb912f1 | 1523 | context[len] = '\0'; |
5d6c3191 | 1524 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); |
1da177e4 | 1525 | if (rc == -ERANGE) { |
314dabb8 JM |
1526 | kfree(context); |
1527 | ||
1da177e4 | 1528 | /* Need a larger buffer. Query for the right size. */ |
5d6c3191 | 1529 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); |
1da177e4 LT |
1530 | if (rc < 0) { |
1531 | dput(dentry); | |
9287aed2 | 1532 | goto out; |
1da177e4 | 1533 | } |
1da177e4 | 1534 | len = rc; |
4cb912f1 | 1535 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1536 | if (!context) { |
1537 | rc = -ENOMEM; | |
1538 | dput(dentry); | |
9287aed2 | 1539 | goto out; |
1da177e4 | 1540 | } |
4cb912f1 | 1541 | context[len] = '\0'; |
5d6c3191 | 1542 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); |
1da177e4 LT |
1543 | } |
1544 | dput(dentry); | |
1545 | if (rc < 0) { | |
1546 | if (rc != -ENODATA) { | |
744ba35e | 1547 | printk(KERN_WARNING "SELinux: %s: getxattr returned " |
dd6f953a | 1548 | "%d for dev=%s ino=%ld\n", __func__, |
1da177e4 LT |
1549 | -rc, inode->i_sb->s_id, inode->i_ino); |
1550 | kfree(context); | |
9287aed2 | 1551 | goto out; |
1da177e4 LT |
1552 | } |
1553 | /* Map ENODATA to the default file SID */ | |
1554 | sid = sbsec->def_sid; | |
1555 | rc = 0; | |
1556 | } else { | |
f5c1d5b2 | 1557 | rc = security_context_to_sid_default(context, rc, &sid, |
869ab514 SS |
1558 | sbsec->def_sid, |
1559 | GFP_NOFS); | |
1da177e4 | 1560 | if (rc) { |
4ba0a8ad EP |
1561 | char *dev = inode->i_sb->s_id; |
1562 | unsigned long ino = inode->i_ino; | |
1563 | ||
1564 | if (rc == -EINVAL) { | |
1565 | if (printk_ratelimit()) | |
1566 | printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " | |
1567 | "context=%s. This indicates you may need to relabel the inode or the " | |
1568 | "filesystem in question.\n", ino, dev, context); | |
1569 | } else { | |
1570 | printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " | |
1571 | "returned %d for dev=%s ino=%ld\n", | |
1572 | __func__, context, -rc, dev, ino); | |
1573 | } | |
1da177e4 LT |
1574 | kfree(context); |
1575 | /* Leave with the unlabeled SID */ | |
1576 | rc = 0; | |
1577 | break; | |
1578 | } | |
1579 | } | |
1580 | kfree(context); | |
1da177e4 LT |
1581 | break; |
1582 | case SECURITY_FS_USE_TASK: | |
9287aed2 | 1583 | sid = task_sid; |
1da177e4 LT |
1584 | break; |
1585 | case SECURITY_FS_USE_TRANS: | |
1586 | /* Default to the fs SID. */ | |
9287aed2 | 1587 | sid = sbsec->sid; |
1da177e4 LT |
1588 | |
1589 | /* Try to obtain a transition SID. */ | |
9287aed2 | 1590 | rc = security_transition_sid(task_sid, sid, sclass, NULL, &sid); |
1da177e4 | 1591 | if (rc) |
9287aed2 | 1592 | goto out; |
1da177e4 | 1593 | break; |
c312feb2 | 1594 | case SECURITY_FS_USE_MNTPOINT: |
9287aed2 | 1595 | sid = sbsec->mntpoint_sid; |
c312feb2 | 1596 | break; |
1da177e4 | 1597 | default: |
c312feb2 | 1598 | /* Default to the fs superblock SID. */ |
9287aed2 | 1599 | sid = sbsec->sid; |
1da177e4 | 1600 | |
134509d5 | 1601 | if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) { |
f64410ec PM |
1602 | /* We must have a dentry to determine the label on |
1603 | * procfs inodes */ | |
1604 | if (opt_dentry) | |
1605 | /* Called from d_instantiate or | |
1606 | * d_splice_alias. */ | |
1607 | dentry = dget(opt_dentry); | |
1608 | else | |
1609 | /* Called from selinux_complete_init, try to | |
1610 | * find a dentry. */ | |
1611 | dentry = d_find_alias(inode); | |
1612 | /* | |
1613 | * This can be hit on boot when a file is accessed | |
1614 | * before the policy is loaded. When we load policy we | |
1615 | * may find inodes that have no dentry on the | |
1616 | * sbsec->isec_head list. No reason to complain as | |
1617 | * these will get fixed up the next time we go through | |
1618 | * inode_doinit() with a dentry, before these inodes | |
1619 | * could be used again by userspace. | |
1620 | */ | |
1621 | if (!dentry) | |
9287aed2 AG |
1622 | goto out; |
1623 | rc = selinux_genfs_get_sid(dentry, sclass, | |
134509d5 | 1624 | sbsec->flags, &sid); |
f64410ec PM |
1625 | dput(dentry); |
1626 | if (rc) | |
9287aed2 | 1627 | goto out; |
1da177e4 LT |
1628 | } |
1629 | break; | |
1630 | } | |
1631 | ||
9287aed2 AG |
1632 | out: |
1633 | spin_lock(&isec->lock); | |
1634 | if (isec->initialized == LABEL_PENDING) { | |
1635 | if (!sid || rc) { | |
1636 | isec->initialized = LABEL_INVALID; | |
1637 | goto out_unlock; | |
1638 | } | |
1639 | ||
1640 | isec->initialized = LABEL_INITIALIZED; | |
1641 | isec->sid = sid; | |
1642 | } | |
1da177e4 | 1643 | |
23970741 | 1644 | out_unlock: |
9287aed2 | 1645 | spin_unlock(&isec->lock); |
1da177e4 LT |
1646 | return rc; |
1647 | } | |
1648 | ||
1649 | /* Convert a Linux signal to an access vector. */ | |
1650 | static inline u32 signal_to_av(int sig) | |
1651 | { | |
1652 | u32 perm = 0; | |
1653 | ||
1654 | switch (sig) { | |
1655 | case SIGCHLD: | |
1656 | /* Commonly granted from child to parent. */ | |
1657 | perm = PROCESS__SIGCHLD; | |
1658 | break; | |
1659 | case SIGKILL: | |
1660 | /* Cannot be caught or ignored */ | |
1661 | perm = PROCESS__SIGKILL; | |
1662 | break; | |
1663 | case SIGSTOP: | |
1664 | /* Cannot be caught or ignored */ | |
1665 | perm = PROCESS__SIGSTOP; | |
1666 | break; | |
1667 | default: | |
1668 | /* All other signals. */ | |
1669 | perm = PROCESS__SIGNAL; | |
1670 | break; | |
1671 | } | |
1672 | ||
1673 | return perm; | |
1674 | } | |
1675 | ||
b68e418c SS |
1676 | #if CAP_LAST_CAP > 63 |
1677 | #error Fix SELinux to handle capabilities > 63. | |
1678 | #endif | |
1679 | ||
1da177e4 | 1680 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1681 | static int cred_has_capability(const struct cred *cred, |
8e4ff6f2 | 1682 | int cap, int audit, bool initns) |
1da177e4 | 1683 | { |
2bf49690 | 1684 | struct common_audit_data ad; |
06112163 | 1685 | struct av_decision avd; |
b68e418c | 1686 | u16 sclass; |
3699c53c | 1687 | u32 sid = cred_sid(cred); |
b68e418c | 1688 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1689 | int rc; |
1da177e4 | 1690 | |
50c205f5 | 1691 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1692 | ad.u.cap = cap; |
1693 | ||
b68e418c SS |
1694 | switch (CAP_TO_INDEX(cap)) { |
1695 | case 0: | |
8e4ff6f2 | 1696 | sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; |
b68e418c SS |
1697 | break; |
1698 | case 1: | |
8e4ff6f2 | 1699 | sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; |
b68e418c SS |
1700 | break; |
1701 | default: | |
1702 | printk(KERN_ERR | |
1703 | "SELinux: out of range capability %d\n", cap); | |
1704 | BUG(); | |
a35c6c83 | 1705 | return -EINVAL; |
b68e418c | 1706 | } |
06112163 | 1707 | |
275bb41e | 1708 | rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); |
9ade0cf4 | 1709 | if (audit == SECURITY_CAP_AUDIT) { |
7b20ea25 | 1710 | int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0); |
9ade0cf4 EP |
1711 | if (rc2) |
1712 | return rc2; | |
1713 | } | |
06112163 | 1714 | return rc; |
1da177e4 LT |
1715 | } |
1716 | ||
1da177e4 LT |
1717 | /* Check whether a task has a particular permission to an inode. |
1718 | The 'adp' parameter is optional and allows other audit | |
1719 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1720 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1721 | struct inode *inode, |
1722 | u32 perms, | |
19e49834 | 1723 | struct common_audit_data *adp) |
1da177e4 | 1724 | { |
1da177e4 | 1725 | struct inode_security_struct *isec; |
275bb41e | 1726 | u32 sid; |
1da177e4 | 1727 | |
e0e81739 DH |
1728 | validate_creds(cred); |
1729 | ||
828dfe1d | 1730 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1731 | return 0; |
1732 | ||
88e67f3b | 1733 | sid = cred_sid(cred); |
1da177e4 LT |
1734 | isec = inode->i_security; |
1735 | ||
19e49834 | 1736 | return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); |
1da177e4 LT |
1737 | } |
1738 | ||
1739 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1740 | the dentry to help the auditing code to more easily generate the | |
1741 | pathname if needed. */ | |
88e67f3b | 1742 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1743 | struct dentry *dentry, |
1744 | u32 av) | |
1745 | { | |
c6f493d6 | 1746 | struct inode *inode = d_backing_inode(dentry); |
2bf49690 | 1747 | struct common_audit_data ad; |
88e67f3b | 1748 | |
50c205f5 | 1749 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1750 | ad.u.dentry = dentry; |
5d226df4 | 1751 | __inode_security_revalidate(inode, dentry, true); |
19e49834 | 1752 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1753 | } |
1754 | ||
1755 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1756 | the path to help the auditing code to more easily generate the | |
1757 | pathname if needed. */ | |
1758 | static inline int path_has_perm(const struct cred *cred, | |
3f7036a0 | 1759 | const struct path *path, |
2875fa00 EP |
1760 | u32 av) |
1761 | { | |
c6f493d6 | 1762 | struct inode *inode = d_backing_inode(path->dentry); |
2875fa00 EP |
1763 | struct common_audit_data ad; |
1764 | ||
50c205f5 | 1765 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1766 | ad.u.path = *path; |
5d226df4 | 1767 | __inode_security_revalidate(inode, path->dentry, true); |
19e49834 | 1768 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1769 | } |
1770 | ||
13f8e981 DH |
1771 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1772 | static inline int file_path_has_perm(const struct cred *cred, | |
1773 | struct file *file, | |
1774 | u32 av) | |
1775 | { | |
1776 | struct common_audit_data ad; | |
1777 | ||
43af5de7 VG |
1778 | ad.type = LSM_AUDIT_DATA_FILE; |
1779 | ad.u.file = file; | |
19e49834 | 1780 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1781 | } |
1782 | ||
1da177e4 LT |
1783 | /* Check whether a task can use an open file descriptor to |
1784 | access an inode in a given way. Check access to the | |
1785 | descriptor itself, and then use dentry_has_perm to | |
1786 | check a particular permission to the file. | |
1787 | Access to the descriptor is implicitly granted if it | |
1788 | has the same SID as the process. If av is zero, then | |
1789 | access to the file is not checked, e.g. for cases | |
1790 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1791 | static int file_has_perm(const struct cred *cred, |
1792 | struct file *file, | |
1793 | u32 av) | |
1da177e4 | 1794 | { |
1da177e4 | 1795 | struct file_security_struct *fsec = file->f_security; |
496ad9aa | 1796 | struct inode *inode = file_inode(file); |
2bf49690 | 1797 | struct common_audit_data ad; |
88e67f3b | 1798 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1799 | int rc; |
1800 | ||
43af5de7 VG |
1801 | ad.type = LSM_AUDIT_DATA_FILE; |
1802 | ad.u.file = file; | |
1da177e4 | 1803 | |
275bb41e DH |
1804 | if (sid != fsec->sid) { |
1805 | rc = avc_has_perm(sid, fsec->sid, | |
1da177e4 LT |
1806 | SECCLASS_FD, |
1807 | FD__USE, | |
1808 | &ad); | |
1809 | if (rc) | |
88e67f3b | 1810 | goto out; |
1da177e4 LT |
1811 | } |
1812 | ||
1813 | /* av is zero if only checking access to the descriptor. */ | |
88e67f3b | 1814 | rc = 0; |
1da177e4 | 1815 | if (av) |
19e49834 | 1816 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1817 | |
88e67f3b DH |
1818 | out: |
1819 | return rc; | |
1da177e4 LT |
1820 | } |
1821 | ||
c3c188b2 DH |
1822 | /* |
1823 | * Determine the label for an inode that might be unioned. | |
1824 | */ | |
c957f6df VG |
1825 | static int |
1826 | selinux_determine_inode_label(const struct task_security_struct *tsec, | |
1827 | struct inode *dir, | |
1828 | const struct qstr *name, u16 tclass, | |
1829 | u32 *_new_isid) | |
c3c188b2 DH |
1830 | { |
1831 | const struct superblock_security_struct *sbsec = dir->i_sb->s_security; | |
c3c188b2 DH |
1832 | |
1833 | if ((sbsec->flags & SE_SBINITIALIZED) && | |
1834 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { | |
1835 | *_new_isid = sbsec->mntpoint_sid; | |
1836 | } else if ((sbsec->flags & SBLABEL_MNT) && | |
1837 | tsec->create_sid) { | |
1838 | *_new_isid = tsec->create_sid; | |
1839 | } else { | |
20cdef8d | 1840 | const struct inode_security_struct *dsec = inode_security(dir); |
c3c188b2 DH |
1841 | return security_transition_sid(tsec->sid, dsec->sid, tclass, |
1842 | name, _new_isid); | |
1843 | } | |
1844 | ||
1845 | return 0; | |
1846 | } | |
1847 | ||
1da177e4 LT |
1848 | /* Check whether a task can create a file. */ |
1849 | static int may_create(struct inode *dir, | |
1850 | struct dentry *dentry, | |
1851 | u16 tclass) | |
1852 | { | |
5fb49870 | 1853 | const struct task_security_struct *tsec = current_security(); |
1da177e4 LT |
1854 | struct inode_security_struct *dsec; |
1855 | struct superblock_security_struct *sbsec; | |
275bb41e | 1856 | u32 sid, newsid; |
2bf49690 | 1857 | struct common_audit_data ad; |
1da177e4 LT |
1858 | int rc; |
1859 | ||
83da53c5 | 1860 | dsec = inode_security(dir); |
1da177e4 LT |
1861 | sbsec = dir->i_sb->s_security; |
1862 | ||
275bb41e | 1863 | sid = tsec->sid; |
275bb41e | 1864 | |
50c205f5 | 1865 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1866 | ad.u.dentry = dentry; |
1da177e4 | 1867 | |
275bb41e | 1868 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
1869 | DIR__ADD_NAME | DIR__SEARCH, |
1870 | &ad); | |
1871 | if (rc) | |
1872 | return rc; | |
1873 | ||
c957f6df VG |
1874 | rc = selinux_determine_inode_label(current_security(), dir, |
1875 | &dentry->d_name, tclass, &newsid); | |
c3c188b2 DH |
1876 | if (rc) |
1877 | return rc; | |
1da177e4 | 1878 | |
275bb41e | 1879 | rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); |
1da177e4 LT |
1880 | if (rc) |
1881 | return rc; | |
1882 | ||
1883 | return avc_has_perm(newsid, sbsec->sid, | |
1884 | SECCLASS_FILESYSTEM, | |
1885 | FILESYSTEM__ASSOCIATE, &ad); | |
1886 | } | |
1887 | ||
828dfe1d EP |
1888 | #define MAY_LINK 0 |
1889 | #define MAY_UNLINK 1 | |
1890 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1891 | |
1892 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1893 | static int may_link(struct inode *dir, | |
1894 | struct dentry *dentry, | |
1895 | int kind) | |
1896 | ||
1897 | { | |
1da177e4 | 1898 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 1899 | struct common_audit_data ad; |
275bb41e | 1900 | u32 sid = current_sid(); |
1da177e4 LT |
1901 | u32 av; |
1902 | int rc; | |
1903 | ||
83da53c5 AG |
1904 | dsec = inode_security(dir); |
1905 | isec = backing_inode_security(dentry); | |
1da177e4 | 1906 | |
50c205f5 | 1907 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1908 | ad.u.dentry = dentry; |
1da177e4 LT |
1909 | |
1910 | av = DIR__SEARCH; | |
1911 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
275bb41e | 1912 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
1913 | if (rc) |
1914 | return rc; | |
1915 | ||
1916 | switch (kind) { | |
1917 | case MAY_LINK: | |
1918 | av = FILE__LINK; | |
1919 | break; | |
1920 | case MAY_UNLINK: | |
1921 | av = FILE__UNLINK; | |
1922 | break; | |
1923 | case MAY_RMDIR: | |
1924 | av = DIR__RMDIR; | |
1925 | break; | |
1926 | default: | |
744ba35e EP |
1927 | printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", |
1928 | __func__, kind); | |
1da177e4 LT |
1929 | return 0; |
1930 | } | |
1931 | ||
275bb41e | 1932 | rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); |
1da177e4 LT |
1933 | return rc; |
1934 | } | |
1935 | ||
1936 | static inline int may_rename(struct inode *old_dir, | |
1937 | struct dentry *old_dentry, | |
1938 | struct inode *new_dir, | |
1939 | struct dentry *new_dentry) | |
1940 | { | |
1da177e4 | 1941 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 1942 | struct common_audit_data ad; |
275bb41e | 1943 | u32 sid = current_sid(); |
1da177e4 LT |
1944 | u32 av; |
1945 | int old_is_dir, new_is_dir; | |
1946 | int rc; | |
1947 | ||
83da53c5 AG |
1948 | old_dsec = inode_security(old_dir); |
1949 | old_isec = backing_inode_security(old_dentry); | |
e36cb0b8 | 1950 | old_is_dir = d_is_dir(old_dentry); |
83da53c5 | 1951 | new_dsec = inode_security(new_dir); |
1da177e4 | 1952 | |
50c205f5 | 1953 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 1954 | |
a269434d | 1955 | ad.u.dentry = old_dentry; |
275bb41e | 1956 | rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
1957 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
1958 | if (rc) | |
1959 | return rc; | |
275bb41e | 1960 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
1961 | old_isec->sclass, FILE__RENAME, &ad); |
1962 | if (rc) | |
1963 | return rc; | |
1964 | if (old_is_dir && new_dir != old_dir) { | |
275bb41e | 1965 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
1966 | old_isec->sclass, DIR__REPARENT, &ad); |
1967 | if (rc) | |
1968 | return rc; | |
1969 | } | |
1970 | ||
a269434d | 1971 | ad.u.dentry = new_dentry; |
1da177e4 | 1972 | av = DIR__ADD_NAME | DIR__SEARCH; |
2c616d4d | 1973 | if (d_is_positive(new_dentry)) |
1da177e4 | 1974 | av |= DIR__REMOVE_NAME; |
275bb41e | 1975 | rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
1976 | if (rc) |
1977 | return rc; | |
2c616d4d | 1978 | if (d_is_positive(new_dentry)) { |
83da53c5 | 1979 | new_isec = backing_inode_security(new_dentry); |
e36cb0b8 | 1980 | new_is_dir = d_is_dir(new_dentry); |
275bb41e | 1981 | rc = avc_has_perm(sid, new_isec->sid, |
1da177e4 LT |
1982 | new_isec->sclass, |
1983 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1984 | if (rc) | |
1985 | return rc; | |
1986 | } | |
1987 | ||
1988 | return 0; | |
1989 | } | |
1990 | ||
1991 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 1992 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
1993 | struct super_block *sb, |
1994 | u32 perms, | |
2bf49690 | 1995 | struct common_audit_data *ad) |
1da177e4 | 1996 | { |
1da177e4 | 1997 | struct superblock_security_struct *sbsec; |
88e67f3b | 1998 | u32 sid = cred_sid(cred); |
1da177e4 | 1999 | |
1da177e4 | 2000 | sbsec = sb->s_security; |
275bb41e | 2001 | return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); |
1da177e4 LT |
2002 | } |
2003 | ||
2004 | /* Convert a Linux mode and permission mask to an access vector. */ | |
2005 | static inline u32 file_mask_to_av(int mode, int mask) | |
2006 | { | |
2007 | u32 av = 0; | |
2008 | ||
dba19c60 | 2009 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
2010 | if (mask & MAY_EXEC) |
2011 | av |= FILE__EXECUTE; | |
2012 | if (mask & MAY_READ) | |
2013 | av |= FILE__READ; | |
2014 | ||
2015 | if (mask & MAY_APPEND) | |
2016 | av |= FILE__APPEND; | |
2017 | else if (mask & MAY_WRITE) | |
2018 | av |= FILE__WRITE; | |
2019 | ||
2020 | } else { | |
2021 | if (mask & MAY_EXEC) | |
2022 | av |= DIR__SEARCH; | |
2023 | if (mask & MAY_WRITE) | |
2024 | av |= DIR__WRITE; | |
2025 | if (mask & MAY_READ) | |
2026 | av |= DIR__READ; | |
2027 | } | |
2028 | ||
2029 | return av; | |
2030 | } | |
2031 | ||
8b6a5a37 EP |
2032 | /* Convert a Linux file to an access vector. */ |
2033 | static inline u32 file_to_av(struct file *file) | |
2034 | { | |
2035 | u32 av = 0; | |
2036 | ||
2037 | if (file->f_mode & FMODE_READ) | |
2038 | av |= FILE__READ; | |
2039 | if (file->f_mode & FMODE_WRITE) { | |
2040 | if (file->f_flags & O_APPEND) | |
2041 | av |= FILE__APPEND; | |
2042 | else | |
2043 | av |= FILE__WRITE; | |
2044 | } | |
2045 | if (!av) { | |
2046 | /* | |
2047 | * Special file opened with flags 3 for ioctl-only use. | |
2048 | */ | |
2049 | av = FILE__IOCTL; | |
2050 | } | |
2051 | ||
2052 | return av; | |
2053 | } | |
2054 | ||
b0c636b9 | 2055 | /* |
8b6a5a37 | 2056 | * Convert a file to an access vector and include the correct open |
b0c636b9 EP |
2057 | * open permission. |
2058 | */ | |
8b6a5a37 | 2059 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 2060 | { |
8b6a5a37 | 2061 | u32 av = file_to_av(file); |
ccb54478 | 2062 | struct inode *inode = file_inode(file); |
b0c636b9 | 2063 | |
ccb54478 | 2064 | if (selinux_policycap_openperm && inode->i_sb->s_magic != SOCKFS_MAGIC) |
49b7b8de EP |
2065 | av |= FILE__OPEN; |
2066 | ||
b0c636b9 EP |
2067 | return av; |
2068 | } | |
2069 | ||
1da177e4 LT |
2070 | /* Hook functions begin here. */ |
2071 | ||
79af7307 SS |
2072 | static int selinux_binder_set_context_mgr(struct task_struct *mgr) |
2073 | { | |
2074 | u32 mysid = current_sid(); | |
2075 | u32 mgrsid = task_sid(mgr); | |
2076 | ||
2077 | return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER, | |
2078 | BINDER__SET_CONTEXT_MGR, NULL); | |
2079 | } | |
2080 | ||
2081 | static int selinux_binder_transaction(struct task_struct *from, | |
2082 | struct task_struct *to) | |
2083 | { | |
2084 | u32 mysid = current_sid(); | |
2085 | u32 fromsid = task_sid(from); | |
2086 | u32 tosid = task_sid(to); | |
2087 | int rc; | |
2088 | ||
2089 | if (mysid != fromsid) { | |
2090 | rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, | |
2091 | BINDER__IMPERSONATE, NULL); | |
2092 | if (rc) | |
2093 | return rc; | |
2094 | } | |
2095 | ||
2096 | return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, | |
2097 | NULL); | |
2098 | } | |
2099 | ||
2100 | static int selinux_binder_transfer_binder(struct task_struct *from, | |
2101 | struct task_struct *to) | |
2102 | { | |
2103 | u32 fromsid = task_sid(from); | |
2104 | u32 tosid = task_sid(to); | |
2105 | ||
2106 | return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, | |
2107 | NULL); | |
2108 | } | |
2109 | ||
2110 | static int selinux_binder_transfer_file(struct task_struct *from, | |
2111 | struct task_struct *to, | |
2112 | struct file *file) | |
2113 | { | |
2114 | u32 sid = task_sid(to); | |
2115 | struct file_security_struct *fsec = file->f_security; | |
83da53c5 | 2116 | struct dentry *dentry = file->f_path.dentry; |
20cdef8d | 2117 | struct inode_security_struct *isec; |
79af7307 SS |
2118 | struct common_audit_data ad; |
2119 | int rc; | |
2120 | ||
2121 | ad.type = LSM_AUDIT_DATA_PATH; | |
2122 | ad.u.path = file->f_path; | |
2123 | ||
2124 | if (sid != fsec->sid) { | |
2125 | rc = avc_has_perm(sid, fsec->sid, | |
2126 | SECCLASS_FD, | |
2127 | FD__USE, | |
2128 | &ad); | |
2129 | if (rc) | |
2130 | return rc; | |
2131 | } | |
2132 | ||
83da53c5 | 2133 | if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
79af7307 SS |
2134 | return 0; |
2135 | ||
20cdef8d | 2136 | isec = backing_inode_security(dentry); |
79af7307 SS |
2137 | return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), |
2138 | &ad); | |
2139 | } | |
2140 | ||
9e48858f | 2141 | static int selinux_ptrace_access_check(struct task_struct *child, |
5cd9c58f | 2142 | unsigned int mode) |
1da177e4 | 2143 | { |
be0554c9 SS |
2144 | u32 sid = current_sid(); |
2145 | u32 csid = task_sid(child); | |
2146 | ||
2147 | if (mode & PTRACE_MODE_READ) | |
275bb41e | 2148 | return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); |
006ebb40 | 2149 | |
be0554c9 | 2150 | return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); |
5cd9c58f DH |
2151 | } |
2152 | ||
2153 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
2154 | { | |
be0554c9 SS |
2155 | return avc_has_perm(task_sid(parent), current_sid(), SECCLASS_PROCESS, |
2156 | PROCESS__PTRACE, NULL); | |
1da177e4 LT |
2157 | } |
2158 | ||
2159 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 2160 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 | 2161 | { |
be0554c9 SS |
2162 | return avc_has_perm(current_sid(), task_sid(target), SECCLASS_PROCESS, |
2163 | PROCESS__GETCAP, NULL); | |
1da177e4 LT |
2164 | } |
2165 | ||
d84f4f99 DH |
2166 | static int selinux_capset(struct cred *new, const struct cred *old, |
2167 | const kernel_cap_t *effective, | |
2168 | const kernel_cap_t *inheritable, | |
2169 | const kernel_cap_t *permitted) | |
1da177e4 | 2170 | { |
be0554c9 SS |
2171 | return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS, |
2172 | PROCESS__SETCAP, NULL); | |
1da177e4 LT |
2173 | } |
2174 | ||
5626d3e8 JM |
2175 | /* |
2176 | * (This comment used to live with the selinux_task_setuid hook, | |
2177 | * which was removed). | |
2178 | * | |
2179 | * Since setuid only affects the current process, and since the SELinux | |
2180 | * controls are not based on the Linux identity attributes, SELinux does not | |
2181 | * need to control this operation. However, SELinux does control the use of | |
2182 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
2183 | */ | |
2184 | ||
6a9de491 EP |
2185 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
2186 | int cap, int audit) | |
1da177e4 | 2187 | { |
8e4ff6f2 | 2188 | return cred_has_capability(cred, cap, audit, ns == &init_user_ns); |
1da177e4 LT |
2189 | } |
2190 | ||
1da177e4 LT |
2191 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
2192 | { | |
88e67f3b | 2193 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2194 | int rc = 0; |
2195 | ||
2196 | if (!sb) | |
2197 | return 0; | |
2198 | ||
2199 | switch (cmds) { | |
828dfe1d EP |
2200 | case Q_SYNC: |
2201 | case Q_QUOTAON: | |
2202 | case Q_QUOTAOFF: | |
2203 | case Q_SETINFO: | |
2204 | case Q_SETQUOTA: | |
88e67f3b | 2205 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
2206 | break; |
2207 | case Q_GETFMT: | |
2208 | case Q_GETINFO: | |
2209 | case Q_GETQUOTA: | |
88e67f3b | 2210 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
2211 | break; |
2212 | default: | |
2213 | rc = 0; /* let the kernel handle invalid cmds */ | |
2214 | break; | |
1da177e4 LT |
2215 | } |
2216 | return rc; | |
2217 | } | |
2218 | ||
2219 | static int selinux_quota_on(struct dentry *dentry) | |
2220 | { | |
88e67f3b DH |
2221 | const struct cred *cred = current_cred(); |
2222 | ||
2875fa00 | 2223 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
2224 | } |
2225 | ||
12b3052c | 2226 | static int selinux_syslog(int type) |
1da177e4 | 2227 | { |
1da177e4 | 2228 | switch (type) { |
d78ca3cd KC |
2229 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2230 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
be0554c9 SS |
2231 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
2232 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); | |
d78ca3cd KC |
2233 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2234 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2235 | /* Set level of messages printed to console */ | |
2236 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
be0554c9 SS |
2237 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, |
2238 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, | |
2239 | NULL); | |
1da177e4 | 2240 | } |
be0554c9 SS |
2241 | /* All other syslog types */ |
2242 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, | |
2243 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); | |
1da177e4 LT |
2244 | } |
2245 | ||
2246 | /* | |
2247 | * Check that a process has enough memory to allocate a new virtual | |
2248 | * mapping. 0 means there is enough memory for the allocation to | |
2249 | * succeed and -ENOMEM implies there is not. | |
2250 | * | |
1da177e4 LT |
2251 | * Do not audit the selinux permission check, as this is applied to all |
2252 | * processes that allocate mappings. | |
2253 | */ | |
34b4e4aa | 2254 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2255 | { |
2256 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2257 | |
b1d9e6b0 | 2258 | rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, |
8e4ff6f2 | 2259 | SECURITY_CAP_NOAUDIT, true); |
1da177e4 LT |
2260 | if (rc == 0) |
2261 | cap_sys_admin = 1; | |
2262 | ||
b1d9e6b0 | 2263 | return cap_sys_admin; |
1da177e4 LT |
2264 | } |
2265 | ||
2266 | /* binprm security operations */ | |
2267 | ||
be0554c9 | 2268 | static u32 ptrace_parent_sid(void) |
0c6181cb PM |
2269 | { |
2270 | u32 sid = 0; | |
2271 | struct task_struct *tracer; | |
2272 | ||
2273 | rcu_read_lock(); | |
be0554c9 | 2274 | tracer = ptrace_parent(current); |
0c6181cb PM |
2275 | if (tracer) |
2276 | sid = task_sid(tracer); | |
2277 | rcu_read_unlock(); | |
2278 | ||
2279 | return sid; | |
2280 | } | |
2281 | ||
7b0d0b40 SS |
2282 | static int check_nnp_nosuid(const struct linux_binprm *bprm, |
2283 | const struct task_security_struct *old_tsec, | |
2284 | const struct task_security_struct *new_tsec) | |
2285 | { | |
2286 | int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); | |
380cf5ba | 2287 | int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); |
7b0d0b40 SS |
2288 | int rc; |
2289 | ||
2290 | if (!nnp && !nosuid) | |
2291 | return 0; /* neither NNP nor nosuid */ | |
2292 | ||
2293 | if (new_tsec->sid == old_tsec->sid) | |
2294 | return 0; /* No change in credentials */ | |
2295 | ||
2296 | /* | |
2297 | * The only transitions we permit under NNP or nosuid | |
2298 | * are transitions to bounded SIDs, i.e. SIDs that are | |
2299 | * guaranteed to only be allowed a subset of the permissions | |
2300 | * of the current SID. | |
2301 | */ | |
2302 | rc = security_bounded_transition(old_tsec->sid, new_tsec->sid); | |
2303 | if (rc) { | |
2304 | /* | |
2305 | * On failure, preserve the errno values for NNP vs nosuid. | |
2306 | * NNP: Operation not permitted for caller. | |
2307 | * nosuid: Permission denied to file. | |
2308 | */ | |
2309 | if (nnp) | |
2310 | return -EPERM; | |
2311 | else | |
2312 | return -EACCES; | |
2313 | } | |
2314 | return 0; | |
2315 | } | |
2316 | ||
a6f76f23 | 2317 | static int selinux_bprm_set_creds(struct linux_binprm *bprm) |
1da177e4 | 2318 | { |
a6f76f23 DH |
2319 | const struct task_security_struct *old_tsec; |
2320 | struct task_security_struct *new_tsec; | |
1da177e4 | 2321 | struct inode_security_struct *isec; |
2bf49690 | 2322 | struct common_audit_data ad; |
496ad9aa | 2323 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2324 | int rc; |
2325 | ||
a6f76f23 DH |
2326 | /* SELinux context only depends on initial program or script and not |
2327 | * the script interpreter */ | |
2328 | if (bprm->cred_prepared) | |
1da177e4 LT |
2329 | return 0; |
2330 | ||
a6f76f23 DH |
2331 | old_tsec = current_security(); |
2332 | new_tsec = bprm->cred->security; | |
83da53c5 | 2333 | isec = inode_security(inode); |
1da177e4 LT |
2334 | |
2335 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2336 | new_tsec->sid = old_tsec->sid; |
2337 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2338 | |
28eba5bf | 2339 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2340 | new_tsec->create_sid = 0; |
2341 | new_tsec->keycreate_sid = 0; | |
2342 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2343 | |
a6f76f23 DH |
2344 | if (old_tsec->exec_sid) { |
2345 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2346 | /* Reset exec SID on execve. */ |
a6f76f23 | 2347 | new_tsec->exec_sid = 0; |
259e5e6c | 2348 | |
7b0d0b40 SS |
2349 | /* Fail on NNP or nosuid if not an allowed transition. */ |
2350 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2351 | if (rc) | |
2352 | return rc; | |
1da177e4 LT |
2353 | } else { |
2354 | /* Check for a default transition on this program. */ | |
a6f76f23 | 2355 | rc = security_transition_sid(old_tsec->sid, isec->sid, |
652bb9b0 EP |
2356 | SECCLASS_PROCESS, NULL, |
2357 | &new_tsec->sid); | |
1da177e4 LT |
2358 | if (rc) |
2359 | return rc; | |
7b0d0b40 SS |
2360 | |
2361 | /* | |
2362 | * Fallback to old SID on NNP or nosuid if not an allowed | |
2363 | * transition. | |
2364 | */ | |
2365 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2366 | if (rc) | |
2367 | new_tsec->sid = old_tsec->sid; | |
1da177e4 LT |
2368 | } |
2369 | ||
43af5de7 VG |
2370 | ad.type = LSM_AUDIT_DATA_FILE; |
2371 | ad.u.file = bprm->file; | |
1da177e4 | 2372 | |
a6f76f23 DH |
2373 | if (new_tsec->sid == old_tsec->sid) { |
2374 | rc = avc_has_perm(old_tsec->sid, isec->sid, | |
1da177e4 LT |
2375 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2376 | if (rc) | |
2377 | return rc; | |
2378 | } else { | |
2379 | /* Check permissions for the transition. */ | |
a6f76f23 | 2380 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
1da177e4 LT |
2381 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2382 | if (rc) | |
2383 | return rc; | |
2384 | ||
a6f76f23 | 2385 | rc = avc_has_perm(new_tsec->sid, isec->sid, |
1da177e4 LT |
2386 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2387 | if (rc) | |
2388 | return rc; | |
2389 | ||
a6f76f23 DH |
2390 | /* Check for shared state */ |
2391 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
2392 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, | |
2393 | SECCLASS_PROCESS, PROCESS__SHARE, | |
2394 | NULL); | |
2395 | if (rc) | |
2396 | return -EPERM; | |
2397 | } | |
2398 | ||
2399 | /* Make sure that anyone attempting to ptrace over a task that | |
2400 | * changes its SID has the appropriate permit */ | |
9227dd2a | 2401 | if (bprm->unsafe & LSM_UNSAFE_PTRACE) { |
be0554c9 | 2402 | u32 ptsid = ptrace_parent_sid(); |
a6f76f23 DH |
2403 | if (ptsid != 0) { |
2404 | rc = avc_has_perm(ptsid, new_tsec->sid, | |
2405 | SECCLASS_PROCESS, | |
2406 | PROCESS__PTRACE, NULL); | |
2407 | if (rc) | |
2408 | return -EPERM; | |
2409 | } | |
2410 | } | |
1da177e4 | 2411 | |
a6f76f23 DH |
2412 | /* Clear any possibly unsafe personality bits on exec: */ |
2413 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
1da177e4 LT |
2414 | } |
2415 | ||
1da177e4 LT |
2416 | return 0; |
2417 | } | |
2418 | ||
828dfe1d | 2419 | static int selinux_bprm_secureexec(struct linux_binprm *bprm) |
1da177e4 | 2420 | { |
5fb49870 | 2421 | const struct task_security_struct *tsec = current_security(); |
275bb41e | 2422 | u32 sid, osid; |
1da177e4 LT |
2423 | int atsecure = 0; |
2424 | ||
275bb41e DH |
2425 | sid = tsec->sid; |
2426 | osid = tsec->osid; | |
2427 | ||
2428 | if (osid != sid) { | |
1da177e4 LT |
2429 | /* Enable secure mode for SIDs transitions unless |
2430 | the noatsecure permission is granted between | |
2431 | the two SIDs, i.e. ahp returns 0. */ | |
275bb41e | 2432 | atsecure = avc_has_perm(osid, sid, |
a6f76f23 DH |
2433 | SECCLASS_PROCESS, |
2434 | PROCESS__NOATSECURE, NULL); | |
1da177e4 LT |
2435 | } |
2436 | ||
b1d9e6b0 | 2437 | return !!atsecure; |
1da177e4 LT |
2438 | } |
2439 | ||
c3c073f8 AV |
2440 | static int match_file(const void *p, struct file *file, unsigned fd) |
2441 | { | |
2442 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2443 | } | |
2444 | ||
1da177e4 | 2445 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2446 | static inline void flush_unauthorized_files(const struct cred *cred, |
2447 | struct files_struct *files) | |
1da177e4 | 2448 | { |
1da177e4 | 2449 | struct file *file, *devnull = NULL; |
b20c8122 | 2450 | struct tty_struct *tty; |
24ec839c | 2451 | int drop_tty = 0; |
c3c073f8 | 2452 | unsigned n; |
1da177e4 | 2453 | |
24ec839c | 2454 | tty = get_current_tty(); |
1da177e4 | 2455 | if (tty) { |
4a510969 | 2456 | spin_lock(&tty->files_lock); |
37dd0bd0 | 2457 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2458 | struct tty_file_private *file_priv; |
37dd0bd0 | 2459 | |
1da177e4 | 2460 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2461 | Use file_path_has_perm on the tty path directly |
2462 | rather than using file_has_perm, as this particular | |
2463 | open file may belong to another process and we are | |
2464 | only interested in the inode-based check here. */ | |
d996b62a NP |
2465 | file_priv = list_first_entry(&tty->tty_files, |
2466 | struct tty_file_private, list); | |
2467 | file = file_priv->file; | |
13f8e981 | 2468 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2469 | drop_tty = 1; |
1da177e4 | 2470 | } |
4a510969 | 2471 | spin_unlock(&tty->files_lock); |
452a00d2 | 2472 | tty_kref_put(tty); |
1da177e4 | 2473 | } |
98a27ba4 EB |
2474 | /* Reset controlling tty. */ |
2475 | if (drop_tty) | |
2476 | no_tty(); | |
1da177e4 LT |
2477 | |
2478 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2479 | n = iterate_fd(files, 0, match_file, cred); |
2480 | if (!n) /* none found? */ | |
2481 | return; | |
1da177e4 | 2482 | |
c3c073f8 | 2483 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2484 | if (IS_ERR(devnull)) |
2485 | devnull = NULL; | |
2486 | /* replace all the matching ones with this */ | |
2487 | do { | |
2488 | replace_fd(n - 1, devnull, 0); | |
2489 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2490 | if (devnull) | |
c3c073f8 | 2491 | fput(devnull); |
1da177e4 LT |
2492 | } |
2493 | ||
a6f76f23 DH |
2494 | /* |
2495 | * Prepare a process for imminent new credential changes due to exec | |
2496 | */ | |
2497 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2498 | { |
a6f76f23 DH |
2499 | struct task_security_struct *new_tsec; |
2500 | struct rlimit *rlim, *initrlim; | |
2501 | int rc, i; | |
d84f4f99 | 2502 | |
a6f76f23 DH |
2503 | new_tsec = bprm->cred->security; |
2504 | if (new_tsec->sid == new_tsec->osid) | |
2505 | return; | |
1da177e4 | 2506 | |
a6f76f23 DH |
2507 | /* Close files for which the new task SID is not authorized. */ |
2508 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2509 | |
a6f76f23 DH |
2510 | /* Always clear parent death signal on SID transitions. */ |
2511 | current->pdeath_signal = 0; | |
0356357c | 2512 | |
a6f76f23 DH |
2513 | /* Check whether the new SID can inherit resource limits from the old |
2514 | * SID. If not, reset all soft limits to the lower of the current | |
2515 | * task's hard limit and the init task's soft limit. | |
2516 | * | |
2517 | * Note that the setting of hard limits (even to lower them) can be | |
2518 | * controlled by the setrlimit check. The inclusion of the init task's | |
2519 | * soft limit into the computation is to avoid resetting soft limits | |
2520 | * higher than the default soft limit for cases where the default is | |
2521 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2522 | */ | |
2523 | rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
2524 | PROCESS__RLIMITINH, NULL); | |
2525 | if (rc) { | |
eb2d55a3 ON |
2526 | /* protect against do_prlimit() */ |
2527 | task_lock(current); | |
a6f76f23 DH |
2528 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2529 | rlim = current->signal->rlim + i; | |
2530 | initrlim = init_task.signal->rlim + i; | |
2531 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2532 | } |
eb2d55a3 | 2533 | task_unlock(current); |
baa73d9e NP |
2534 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) |
2535 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2536 | } |
2537 | } | |
2538 | ||
2539 | /* | |
a6f76f23 DH |
2540 | * Clean up the process immediately after the installation of new credentials |
2541 | * due to exec | |
1da177e4 | 2542 | */ |
a6f76f23 | 2543 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2544 | { |
a6f76f23 | 2545 | const struct task_security_struct *tsec = current_security(); |
1da177e4 | 2546 | struct itimerval itimer; |
a6f76f23 | 2547 | u32 osid, sid; |
1da177e4 LT |
2548 | int rc, i; |
2549 | ||
a6f76f23 DH |
2550 | osid = tsec->osid; |
2551 | sid = tsec->sid; | |
2552 | ||
2553 | if (sid == osid) | |
1da177e4 LT |
2554 | return; |
2555 | ||
a6f76f23 DH |
2556 | /* Check whether the new SID can inherit signal state from the old SID. |
2557 | * If not, clear itimers to avoid subsequent signal generation and | |
2558 | * flush and unblock signals. | |
2559 | * | |
2560 | * This must occur _after_ the task SID has been updated so that any | |
2561 | * kill done after the flush will be checked against the new SID. | |
2562 | */ | |
2563 | rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 | 2564 | if (rc) { |
baa73d9e NP |
2565 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) { |
2566 | memset(&itimer, 0, sizeof itimer); | |
2567 | for (i = 0; i < 3; i++) | |
2568 | do_setitimer(i, &itimer, NULL); | |
2569 | } | |
1da177e4 | 2570 | spin_lock_irq(¤t->sighand->siglock); |
9e7c8f8c ON |
2571 | if (!fatal_signal_pending(current)) { |
2572 | flush_sigqueue(¤t->pending); | |
2573 | flush_sigqueue(¤t->signal->shared_pending); | |
3bcac026 DH |
2574 | flush_signal_handlers(current, 1); |
2575 | sigemptyset(¤t->blocked); | |
9e7c8f8c | 2576 | recalc_sigpending(); |
3bcac026 | 2577 | } |
1da177e4 LT |
2578 | spin_unlock_irq(¤t->sighand->siglock); |
2579 | } | |
2580 | ||
a6f76f23 DH |
2581 | /* Wake up the parent if it is waiting so that it can recheck |
2582 | * wait permission to the new task SID. */ | |
ecd6de3c | 2583 | read_lock(&tasklist_lock); |
0b7570e7 | 2584 | __wake_up_parent(current, current->real_parent); |
ecd6de3c | 2585 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2586 | } |
2587 | ||
2588 | /* superblock security operations */ | |
2589 | ||
2590 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2591 | { | |
2592 | return superblock_alloc_security(sb); | |
2593 | } | |
2594 | ||
2595 | static void selinux_sb_free_security(struct super_block *sb) | |
2596 | { | |
2597 | superblock_free_security(sb); | |
2598 | } | |
2599 | ||
2600 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2601 | { | |
2602 | if (plen > olen) | |
2603 | return 0; | |
2604 | ||
2605 | return !memcmp(prefix, option, plen); | |
2606 | } | |
2607 | ||
2608 | static inline int selinux_option(char *option, int len) | |
2609 | { | |
832cbd9a EP |
2610 | return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || |
2611 | match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || | |
2612 | match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || | |
11689d47 DQ |
2613 | match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || |
2614 | match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); | |
1da177e4 LT |
2615 | } |
2616 | ||
2617 | static inline void take_option(char **to, char *from, int *first, int len) | |
2618 | { | |
2619 | if (!*first) { | |
2620 | **to = ','; | |
2621 | *to += 1; | |
3528a953 | 2622 | } else |
1da177e4 LT |
2623 | *first = 0; |
2624 | memcpy(*to, from, len); | |
2625 | *to += len; | |
2626 | } | |
2627 | ||
828dfe1d EP |
2628 | static inline void take_selinux_option(char **to, char *from, int *first, |
2629 | int len) | |
3528a953 CO |
2630 | { |
2631 | int current_size = 0; | |
2632 | ||
2633 | if (!*first) { | |
2634 | **to = '|'; | |
2635 | *to += 1; | |
828dfe1d | 2636 | } else |
3528a953 CO |
2637 | *first = 0; |
2638 | ||
2639 | while (current_size < len) { | |
2640 | if (*from != '"') { | |
2641 | **to = *from; | |
2642 | *to += 1; | |
2643 | } | |
2644 | from += 1; | |
2645 | current_size += 1; | |
2646 | } | |
2647 | } | |
2648 | ||
e0007529 | 2649 | static int selinux_sb_copy_data(char *orig, char *copy) |
1da177e4 LT |
2650 | { |
2651 | int fnosec, fsec, rc = 0; | |
2652 | char *in_save, *in_curr, *in_end; | |
2653 | char *sec_curr, *nosec_save, *nosec; | |
3528a953 | 2654 | int open_quote = 0; |
1da177e4 LT |
2655 | |
2656 | in_curr = orig; | |
2657 | sec_curr = copy; | |
2658 | ||
1da177e4 LT |
2659 | nosec = (char *)get_zeroed_page(GFP_KERNEL); |
2660 | if (!nosec) { | |
2661 | rc = -ENOMEM; | |
2662 | goto out; | |
2663 | } | |
2664 | ||
2665 | nosec_save = nosec; | |
2666 | fnosec = fsec = 1; | |
2667 | in_save = in_end = orig; | |
2668 | ||
2669 | do { | |
3528a953 CO |
2670 | if (*in_end == '"') |
2671 | open_quote = !open_quote; | |
2672 | if ((*in_end == ',' && open_quote == 0) || | |
2673 | *in_end == '\0') { | |
1da177e4 LT |
2674 | int len = in_end - in_curr; |
2675 | ||
2676 | if (selinux_option(in_curr, len)) | |
3528a953 | 2677 | take_selinux_option(&sec_curr, in_curr, &fsec, len); |
1da177e4 LT |
2678 | else |
2679 | take_option(&nosec, in_curr, &fnosec, len); | |
2680 | ||
2681 | in_curr = in_end + 1; | |
2682 | } | |
2683 | } while (*in_end++); | |
2684 | ||
6931dfc9 | 2685 | strcpy(in_save, nosec_save); |
da3caa20 | 2686 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
2687 | out: |
2688 | return rc; | |
2689 | } | |
2690 | ||
026eb167 EP |
2691 | static int selinux_sb_remount(struct super_block *sb, void *data) |
2692 | { | |
2693 | int rc, i, *flags; | |
2694 | struct security_mnt_opts opts; | |
2695 | char *secdata, **mount_options; | |
2696 | struct superblock_security_struct *sbsec = sb->s_security; | |
2697 | ||
2698 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2699 | return 0; | |
2700 | ||
2701 | if (!data) | |
2702 | return 0; | |
2703 | ||
2704 | if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) | |
2705 | return 0; | |
2706 | ||
2707 | security_init_mnt_opts(&opts); | |
2708 | secdata = alloc_secdata(); | |
2709 | if (!secdata) | |
2710 | return -ENOMEM; | |
2711 | rc = selinux_sb_copy_data(data, secdata); | |
2712 | if (rc) | |
2713 | goto out_free_secdata; | |
2714 | ||
2715 | rc = selinux_parse_opts_str(secdata, &opts); | |
2716 | if (rc) | |
2717 | goto out_free_secdata; | |
2718 | ||
2719 | mount_options = opts.mnt_opts; | |
2720 | flags = opts.mnt_opts_flags; | |
2721 | ||
2722 | for (i = 0; i < opts.num_mnt_opts; i++) { | |
2723 | u32 sid; | |
026eb167 | 2724 | |
12f348b9 | 2725 | if (flags[i] == SBLABEL_MNT) |
026eb167 | 2726 | continue; |
44be2f65 | 2727 | rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL); |
026eb167 | 2728 | if (rc) { |
44be2f65 | 2729 | printk(KERN_WARNING "SELinux: security_context_str_to_sid" |
29b1deb2 LT |
2730 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
2731 | mount_options[i], sb->s_id, sb->s_type->name, rc); | |
026eb167 EP |
2732 | goto out_free_opts; |
2733 | } | |
2734 | rc = -EINVAL; | |
2735 | switch (flags[i]) { | |
2736 | case FSCONTEXT_MNT: | |
2737 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) | |
2738 | goto out_bad_option; | |
2739 | break; | |
2740 | case CONTEXT_MNT: | |
2741 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2742 | goto out_bad_option; | |
2743 | break; | |
2744 | case ROOTCONTEXT_MNT: { | |
2745 | struct inode_security_struct *root_isec; | |
83da53c5 | 2746 | root_isec = backing_inode_security(sb->s_root); |
026eb167 EP |
2747 | |
2748 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2749 | goto out_bad_option; | |
2750 | break; | |
2751 | } | |
2752 | case DEFCONTEXT_MNT: | |
2753 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2754 | goto out_bad_option; | |
2755 | break; | |
2756 | default: | |
2757 | goto out_free_opts; | |
2758 | } | |
2759 | } | |
2760 | ||
2761 | rc = 0; | |
2762 | out_free_opts: | |
2763 | security_free_mnt_opts(&opts); | |
2764 | out_free_secdata: | |
2765 | free_secdata(secdata); | |
2766 | return rc; | |
2767 | out_bad_option: | |
2768 | printk(KERN_WARNING "SELinux: unable to change security options " | |
29b1deb2 LT |
2769 | "during remount (dev %s, type=%s)\n", sb->s_id, |
2770 | sb->s_type->name); | |
026eb167 EP |
2771 | goto out_free_opts; |
2772 | } | |
2773 | ||
12204e24 | 2774 | static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) |
1da177e4 | 2775 | { |
88e67f3b | 2776 | const struct cred *cred = current_cred(); |
2bf49690 | 2777 | struct common_audit_data ad; |
1da177e4 LT |
2778 | int rc; |
2779 | ||
2780 | rc = superblock_doinit(sb, data); | |
2781 | if (rc) | |
2782 | return rc; | |
2783 | ||
74192246 JM |
2784 | /* Allow all mounts performed by the kernel */ |
2785 | if (flags & MS_KERNMOUNT) | |
2786 | return 0; | |
2787 | ||
50c205f5 | 2788 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2789 | ad.u.dentry = sb->s_root; |
88e67f3b | 2790 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2791 | } |
2792 | ||
726c3342 | 2793 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2794 | { |
88e67f3b | 2795 | const struct cred *cred = current_cred(); |
2bf49690 | 2796 | struct common_audit_data ad; |
1da177e4 | 2797 | |
50c205f5 | 2798 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2799 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2800 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2801 | } |
2802 | ||
808d4e3c | 2803 | static int selinux_mount(const char *dev_name, |
8a04c43b | 2804 | const struct path *path, |
808d4e3c | 2805 | const char *type, |
828dfe1d EP |
2806 | unsigned long flags, |
2807 | void *data) | |
1da177e4 | 2808 | { |
88e67f3b | 2809 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2810 | |
2811 | if (flags & MS_REMOUNT) | |
d8c9584e | 2812 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2813 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2814 | else |
2875fa00 | 2815 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2816 | } |
2817 | ||
2818 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2819 | { | |
88e67f3b | 2820 | const struct cred *cred = current_cred(); |
1da177e4 | 2821 | |
88e67f3b | 2822 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2823 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2824 | } |
2825 | ||
2826 | /* inode security operations */ | |
2827 | ||
2828 | static int selinux_inode_alloc_security(struct inode *inode) | |
2829 | { | |
2830 | return inode_alloc_security(inode); | |
2831 | } | |
2832 | ||
2833 | static void selinux_inode_free_security(struct inode *inode) | |
2834 | { | |
2835 | inode_free_security(inode); | |
2836 | } | |
2837 | ||
d47be3df | 2838 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
4f3ccd76 | 2839 | const struct qstr *name, void **ctx, |
d47be3df DQ |
2840 | u32 *ctxlen) |
2841 | { | |
d47be3df DQ |
2842 | u32 newsid; |
2843 | int rc; | |
2844 | ||
c957f6df VG |
2845 | rc = selinux_determine_inode_label(current_security(), |
2846 | d_inode(dentry->d_parent), name, | |
c3c188b2 DH |
2847 | inode_mode_to_security_class(mode), |
2848 | &newsid); | |
2849 | if (rc) | |
2850 | return rc; | |
d47be3df DQ |
2851 | |
2852 | return security_sid_to_context(newsid, (char **)ctx, ctxlen); | |
2853 | } | |
2854 | ||
a518b0a5 VG |
2855 | static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, |
2856 | struct qstr *name, | |
2857 | const struct cred *old, | |
2858 | struct cred *new) | |
2859 | { | |
2860 | u32 newsid; | |
2861 | int rc; | |
2862 | struct task_security_struct *tsec; | |
2863 | ||
2864 | rc = selinux_determine_inode_label(old->security, | |
2865 | d_inode(dentry->d_parent), name, | |
2866 | inode_mode_to_security_class(mode), | |
2867 | &newsid); | |
2868 | if (rc) | |
2869 | return rc; | |
2870 | ||
2871 | tsec = new->security; | |
2872 | tsec->create_sid = newsid; | |
2873 | return 0; | |
2874 | } | |
2875 | ||
5e41ff9e | 2876 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
2877 | const struct qstr *qstr, |
2878 | const char **name, | |
2a7dba39 | 2879 | void **value, size_t *len) |
5e41ff9e | 2880 | { |
5fb49870 | 2881 | const struct task_security_struct *tsec = current_security(); |
5e41ff9e | 2882 | struct superblock_security_struct *sbsec; |
275bb41e | 2883 | u32 sid, newsid, clen; |
5e41ff9e | 2884 | int rc; |
9548906b | 2885 | char *context; |
5e41ff9e | 2886 | |
5e41ff9e | 2887 | sbsec = dir->i_sb->s_security; |
5e41ff9e | 2888 | |
275bb41e DH |
2889 | sid = tsec->sid; |
2890 | newsid = tsec->create_sid; | |
2891 | ||
c957f6df | 2892 | rc = selinux_determine_inode_label(current_security(), |
c3c188b2 DH |
2893 | dir, qstr, |
2894 | inode_mode_to_security_class(inode->i_mode), | |
2895 | &newsid); | |
2896 | if (rc) | |
2897 | return rc; | |
5e41ff9e | 2898 | |
296fddf7 | 2899 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 2900 | if (sbsec->flags & SE_SBINITIALIZED) { |
296fddf7 EP |
2901 | struct inode_security_struct *isec = inode->i_security; |
2902 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
2903 | isec->sid = newsid; | |
6f3be9f5 | 2904 | isec->initialized = LABEL_INITIALIZED; |
296fddf7 | 2905 | } |
5e41ff9e | 2906 | |
12f348b9 | 2907 | if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT)) |
25a74f3b SS |
2908 | return -EOPNOTSUPP; |
2909 | ||
9548906b TH |
2910 | if (name) |
2911 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 2912 | |
570bc1c2 | 2913 | if (value && len) { |
12b29f34 | 2914 | rc = security_sid_to_context_force(newsid, &context, &clen); |
9548906b | 2915 | if (rc) |
570bc1c2 | 2916 | return rc; |
570bc1c2 SS |
2917 | *value = context; |
2918 | *len = clen; | |
5e41ff9e | 2919 | } |
5e41ff9e | 2920 | |
5e41ff9e SS |
2921 | return 0; |
2922 | } | |
2923 | ||
4acdaf27 | 2924 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
2925 | { |
2926 | return may_create(dir, dentry, SECCLASS_FILE); | |
2927 | } | |
2928 | ||
1da177e4 LT |
2929 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2930 | { | |
1da177e4 LT |
2931 | return may_link(dir, old_dentry, MAY_LINK); |
2932 | } | |
2933 | ||
1da177e4 LT |
2934 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2935 | { | |
1da177e4 LT |
2936 | return may_link(dir, dentry, MAY_UNLINK); |
2937 | } | |
2938 | ||
2939 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2940 | { | |
2941 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2942 | } | |
2943 | ||
18bb1db3 | 2944 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
2945 | { |
2946 | return may_create(dir, dentry, SECCLASS_DIR); | |
2947 | } | |
2948 | ||
1da177e4 LT |
2949 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2950 | { | |
2951 | return may_link(dir, dentry, MAY_RMDIR); | |
2952 | } | |
2953 | ||
1a67aafb | 2954 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 2955 | { |
1da177e4 LT |
2956 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
2957 | } | |
2958 | ||
1da177e4 | 2959 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 2960 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
2961 | { |
2962 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2963 | } | |
2964 | ||
1da177e4 LT |
2965 | static int selinux_inode_readlink(struct dentry *dentry) |
2966 | { | |
88e67f3b DH |
2967 | const struct cred *cred = current_cred(); |
2968 | ||
2875fa00 | 2969 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
2970 | } |
2971 | ||
bda0be7a N |
2972 | static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, |
2973 | bool rcu) | |
1da177e4 | 2974 | { |
88e67f3b | 2975 | const struct cred *cred = current_cred(); |
bda0be7a N |
2976 | struct common_audit_data ad; |
2977 | struct inode_security_struct *isec; | |
2978 | u32 sid; | |
1da177e4 | 2979 | |
bda0be7a N |
2980 | validate_creds(cred); |
2981 | ||
2982 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
2983 | ad.u.dentry = dentry; | |
2984 | sid = cred_sid(cred); | |
5d226df4 AG |
2985 | isec = inode_security_rcu(inode, rcu); |
2986 | if (IS_ERR(isec)) | |
2987 | return PTR_ERR(isec); | |
bda0be7a N |
2988 | |
2989 | return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad, | |
2990 | rcu ? MAY_NOT_BLOCK : 0); | |
1da177e4 LT |
2991 | } |
2992 | ||
d4cf970d EP |
2993 | static noinline int audit_inode_permission(struct inode *inode, |
2994 | u32 perms, u32 audited, u32 denied, | |
626b9740 | 2995 | int result, |
d4cf970d | 2996 | unsigned flags) |
1da177e4 | 2997 | { |
b782e0a6 | 2998 | struct common_audit_data ad; |
d4cf970d EP |
2999 | struct inode_security_struct *isec = inode->i_security; |
3000 | int rc; | |
3001 | ||
50c205f5 | 3002 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
3003 | ad.u.inode = inode; |
3004 | ||
3005 | rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, | |
626b9740 | 3006 | audited, denied, result, &ad, flags); |
d4cf970d EP |
3007 | if (rc) |
3008 | return rc; | |
3009 | return 0; | |
3010 | } | |
3011 | ||
e74f71eb | 3012 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 3013 | { |
88e67f3b | 3014 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
3015 | u32 perms; |
3016 | bool from_access; | |
cf1dd1da | 3017 | unsigned flags = mask & MAY_NOT_BLOCK; |
2e334057 EP |
3018 | struct inode_security_struct *isec; |
3019 | u32 sid; | |
3020 | struct av_decision avd; | |
3021 | int rc, rc2; | |
3022 | u32 audited, denied; | |
1da177e4 | 3023 | |
b782e0a6 | 3024 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
3025 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
3026 | ||
b782e0a6 EP |
3027 | /* No permission to check. Existence test. */ |
3028 | if (!mask) | |
1da177e4 | 3029 | return 0; |
1da177e4 | 3030 | |
2e334057 | 3031 | validate_creds(cred); |
b782e0a6 | 3032 | |
2e334057 EP |
3033 | if (unlikely(IS_PRIVATE(inode))) |
3034 | return 0; | |
b782e0a6 EP |
3035 | |
3036 | perms = file_mask_to_av(inode->i_mode, mask); | |
3037 | ||
2e334057 | 3038 | sid = cred_sid(cred); |
5d226df4 AG |
3039 | isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK); |
3040 | if (IS_ERR(isec)) | |
3041 | return PTR_ERR(isec); | |
2e334057 EP |
3042 | |
3043 | rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd); | |
3044 | audited = avc_audit_required(perms, &avd, rc, | |
3045 | from_access ? FILE__AUDIT_ACCESS : 0, | |
3046 | &denied); | |
3047 | if (likely(!audited)) | |
3048 | return rc; | |
3049 | ||
626b9740 | 3050 | rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags); |
2e334057 EP |
3051 | if (rc2) |
3052 | return rc2; | |
3053 | return rc; | |
1da177e4 LT |
3054 | } |
3055 | ||
3056 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
3057 | { | |
88e67f3b | 3058 | const struct cred *cred = current_cred(); |
ccb54478 | 3059 | struct inode *inode = d_backing_inode(dentry); |
bc6a6008 | 3060 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 3061 | __u32 av = FILE__WRITE; |
1da177e4 | 3062 | |
bc6a6008 AW |
3063 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
3064 | if (ia_valid & ATTR_FORCE) { | |
3065 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
3066 | ATTR_FORCE); | |
3067 | if (!ia_valid) | |
3068 | return 0; | |
3069 | } | |
1da177e4 | 3070 | |
bc6a6008 AW |
3071 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
3072 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 3073 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 3074 | |
ccb54478 SS |
3075 | if (selinux_policycap_openperm && |
3076 | inode->i_sb->s_magic != SOCKFS_MAGIC && | |
3077 | (ia_valid & ATTR_SIZE) && | |
3078 | !(ia_valid & ATTR_FILE)) | |
95dbf739 EP |
3079 | av |= FILE__OPEN; |
3080 | ||
3081 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
3082 | } |
3083 | ||
3f7036a0 | 3084 | static int selinux_inode_getattr(const struct path *path) |
1da177e4 | 3085 | { |
3f7036a0 | 3086 | return path_has_perm(current_cred(), path, FILE__GETATTR); |
1da177e4 LT |
3087 | } |
3088 | ||
8f0cfa52 | 3089 | static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) |
b5376771 | 3090 | { |
88e67f3b DH |
3091 | const struct cred *cred = current_cred(); |
3092 | ||
b5376771 SH |
3093 | if (!strncmp(name, XATTR_SECURITY_PREFIX, |
3094 | sizeof XATTR_SECURITY_PREFIX - 1)) { | |
3095 | if (!strcmp(name, XATTR_NAME_CAPS)) { | |
3096 | if (!capable(CAP_SETFCAP)) | |
3097 | return -EPERM; | |
3098 | } else if (!capable(CAP_SYS_ADMIN)) { | |
3099 | /* A different attribute in the security namespace. | |
3100 | Restrict to administrator. */ | |
3101 | return -EPERM; | |
3102 | } | |
3103 | } | |
3104 | ||
3105 | /* Not an attribute we recognize, so just check the | |
3106 | ordinary setattr permission. */ | |
2875fa00 | 3107 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
b5376771 SH |
3108 | } |
3109 | ||
db59000a SS |
3110 | static bool has_cap_mac_admin(bool audit) |
3111 | { | |
3112 | const struct cred *cred = current_cred(); | |
3113 | int cap_audit = audit ? SECURITY_CAP_AUDIT : SECURITY_CAP_NOAUDIT; | |
3114 | ||
3115 | if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, cap_audit)) | |
3116 | return false; | |
3117 | if (cred_has_capability(cred, CAP_MAC_ADMIN, cap_audit, true)) | |
3118 | return false; | |
3119 | return true; | |
3120 | } | |
3121 | ||
8f0cfa52 DH |
3122 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
3123 | const void *value, size_t size, int flags) | |
1da177e4 | 3124 | { |
c6f493d6 | 3125 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3126 | struct inode_security_struct *isec; |
1da177e4 | 3127 | struct superblock_security_struct *sbsec; |
2bf49690 | 3128 | struct common_audit_data ad; |
275bb41e | 3129 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
3130 | int rc = 0; |
3131 | ||
b5376771 SH |
3132 | if (strcmp(name, XATTR_NAME_SELINUX)) |
3133 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
3134 | |
3135 | sbsec = inode->i_sb->s_security; | |
12f348b9 | 3136 | if (!(sbsec->flags & SBLABEL_MNT)) |
1da177e4 LT |
3137 | return -EOPNOTSUPP; |
3138 | ||
2e149670 | 3139 | if (!inode_owner_or_capable(inode)) |
1da177e4 LT |
3140 | return -EPERM; |
3141 | ||
50c205f5 | 3142 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 3143 | ad.u.dentry = dentry; |
1da177e4 | 3144 | |
20cdef8d | 3145 | isec = backing_inode_security(dentry); |
275bb41e | 3146 | rc = avc_has_perm(sid, isec->sid, isec->sclass, |
1da177e4 LT |
3147 | FILE__RELABELFROM, &ad); |
3148 | if (rc) | |
3149 | return rc; | |
3150 | ||
52a4c640 | 3151 | rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); |
12b29f34 | 3152 | if (rc == -EINVAL) { |
db59000a | 3153 | if (!has_cap_mac_admin(true)) { |
d6ea83ec EP |
3154 | struct audit_buffer *ab; |
3155 | size_t audit_size; | |
3156 | const char *str; | |
3157 | ||
3158 | /* We strip a nul only if it is at the end, otherwise the | |
3159 | * context contains a nul and we should audit that */ | |
e3fea3f7 AV |
3160 | if (value) { |
3161 | str = value; | |
3162 | if (str[size - 1] == '\0') | |
3163 | audit_size = size - 1; | |
3164 | else | |
3165 | audit_size = size; | |
3166 | } else { | |
3167 | str = ""; | |
3168 | audit_size = 0; | |
3169 | } | |
d6ea83ec EP |
3170 | ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); |
3171 | audit_log_format(ab, "op=setxattr invalid_context="); | |
3172 | audit_log_n_untrustedstring(ab, value, audit_size); | |
3173 | audit_log_end(ab); | |
3174 | ||
12b29f34 | 3175 | return rc; |
d6ea83ec | 3176 | } |
12b29f34 SS |
3177 | rc = security_context_to_sid_force(value, size, &newsid); |
3178 | } | |
1da177e4 LT |
3179 | if (rc) |
3180 | return rc; | |
3181 | ||
275bb41e | 3182 | rc = avc_has_perm(sid, newsid, isec->sclass, |
1da177e4 LT |
3183 | FILE__RELABELTO, &ad); |
3184 | if (rc) | |
3185 | return rc; | |
3186 | ||
275bb41e | 3187 | rc = security_validate_transition(isec->sid, newsid, sid, |
828dfe1d | 3188 | isec->sclass); |
1da177e4 LT |
3189 | if (rc) |
3190 | return rc; | |
3191 | ||
3192 | return avc_has_perm(newsid, | |
3193 | sbsec->sid, | |
3194 | SECCLASS_FILESYSTEM, | |
3195 | FILESYSTEM__ASSOCIATE, | |
3196 | &ad); | |
3197 | } | |
3198 | ||
8f0cfa52 | 3199 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 3200 | const void *value, size_t size, |
8f0cfa52 | 3201 | int flags) |
1da177e4 | 3202 | { |
c6f493d6 | 3203 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3204 | struct inode_security_struct *isec; |
1da177e4 LT |
3205 | u32 newsid; |
3206 | int rc; | |
3207 | ||
3208 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
3209 | /* Not an attribute we recognize, so nothing to do. */ | |
3210 | return; | |
3211 | } | |
3212 | ||
12b29f34 | 3213 | rc = security_context_to_sid_force(value, size, &newsid); |
1da177e4 | 3214 | if (rc) { |
12b29f34 SS |
3215 | printk(KERN_ERR "SELinux: unable to map context to SID" |
3216 | "for (%s, %lu), rc=%d\n", | |
3217 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
3218 | return; |
3219 | } | |
3220 | ||
20cdef8d | 3221 | isec = backing_inode_security(dentry); |
9287aed2 | 3222 | spin_lock(&isec->lock); |
aa9c2669 | 3223 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3224 | isec->sid = newsid; |
6f3be9f5 | 3225 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3226 | spin_unlock(&isec->lock); |
aa9c2669 | 3227 | |
1da177e4 LT |
3228 | return; |
3229 | } | |
3230 | ||
8f0cfa52 | 3231 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 3232 | { |
88e67f3b DH |
3233 | const struct cred *cred = current_cred(); |
3234 | ||
2875fa00 | 3235 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3236 | } |
3237 | ||
828dfe1d | 3238 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 3239 | { |
88e67f3b DH |
3240 | const struct cred *cred = current_cred(); |
3241 | ||
2875fa00 | 3242 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3243 | } |
3244 | ||
8f0cfa52 | 3245 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 3246 | { |
b5376771 SH |
3247 | if (strcmp(name, XATTR_NAME_SELINUX)) |
3248 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
3249 | |
3250 | /* No one is allowed to remove a SELinux security label. | |
3251 | You can change the label, but all data must be labeled. */ | |
3252 | return -EACCES; | |
3253 | } | |
3254 | ||
d381d8a9 | 3255 | /* |
abc69bb6 | 3256 | * Copy the inode security context value to the user. |
d381d8a9 JM |
3257 | * |
3258 | * Permission check is handled by selinux_inode_getxattr hook. | |
3259 | */ | |
ea861dfd | 3260 | static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 3261 | { |
42492594 DQ |
3262 | u32 size; |
3263 | int error; | |
3264 | char *context = NULL; | |
20cdef8d | 3265 | struct inode_security_struct *isec; |
d381d8a9 | 3266 | |
8c8570fb DK |
3267 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
3268 | return -EOPNOTSUPP; | |
d381d8a9 | 3269 | |
abc69bb6 SS |
3270 | /* |
3271 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3272 | * value even if it is not defined by current policy; otherwise, | |
3273 | * use the in-core value under current policy. | |
3274 | * Use the non-auditing forms of the permission checks since | |
3275 | * getxattr may be called by unprivileged processes commonly | |
3276 | * and lack of permission just means that we fall back to the | |
3277 | * in-core context value, not a denial. | |
3278 | */ | |
20cdef8d | 3279 | isec = inode_security(inode); |
db59000a | 3280 | if (has_cap_mac_admin(false)) |
abc69bb6 SS |
3281 | error = security_sid_to_context_force(isec->sid, &context, |
3282 | &size); | |
3283 | else | |
3284 | error = security_sid_to_context(isec->sid, &context, &size); | |
42492594 DQ |
3285 | if (error) |
3286 | return error; | |
3287 | error = size; | |
3288 | if (alloc) { | |
3289 | *buffer = context; | |
3290 | goto out_nofree; | |
3291 | } | |
3292 | kfree(context); | |
3293 | out_nofree: | |
3294 | return error; | |
1da177e4 LT |
3295 | } |
3296 | ||
3297 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 3298 | const void *value, size_t size, int flags) |
1da177e4 | 3299 | { |
2c97165b | 3300 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
1da177e4 LT |
3301 | u32 newsid; |
3302 | int rc; | |
3303 | ||
3304 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3305 | return -EOPNOTSUPP; | |
3306 | ||
3307 | if (!value || !size) | |
3308 | return -EACCES; | |
3309 | ||
20ba96ae | 3310 | rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); |
1da177e4 LT |
3311 | if (rc) |
3312 | return rc; | |
3313 | ||
9287aed2 | 3314 | spin_lock(&isec->lock); |
aa9c2669 | 3315 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3316 | isec->sid = newsid; |
6f3be9f5 | 3317 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3318 | spin_unlock(&isec->lock); |
1da177e4 LT |
3319 | return 0; |
3320 | } | |
3321 | ||
3322 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3323 | { | |
3324 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3325 | if (buffer && len <= buffer_size) | |
3326 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3327 | return len; | |
3328 | } | |
3329 | ||
d6335d77 | 3330 | static void selinux_inode_getsecid(struct inode *inode, u32 *secid) |
713a04ae | 3331 | { |
e817c2f3 | 3332 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
713a04ae AD |
3333 | *secid = isec->sid; |
3334 | } | |
3335 | ||
56909eb3 VG |
3336 | static int selinux_inode_copy_up(struct dentry *src, struct cred **new) |
3337 | { | |
3338 | u32 sid; | |
3339 | struct task_security_struct *tsec; | |
3340 | struct cred *new_creds = *new; | |
3341 | ||
3342 | if (new_creds == NULL) { | |
3343 | new_creds = prepare_creds(); | |
3344 | if (!new_creds) | |
3345 | return -ENOMEM; | |
3346 | } | |
3347 | ||
3348 | tsec = new_creds->security; | |
3349 | /* Get label from overlay inode and set it in create_sid */ | |
3350 | selinux_inode_getsecid(d_inode(src), &sid); | |
3351 | tsec->create_sid = sid; | |
3352 | *new = new_creds; | |
3353 | return 0; | |
3354 | } | |
3355 | ||
19472b69 VG |
3356 | static int selinux_inode_copy_up_xattr(const char *name) |
3357 | { | |
3358 | /* The copy_up hook above sets the initial context on an inode, but we | |
3359 | * don't then want to overwrite it by blindly copying all the lower | |
3360 | * xattrs up. Instead, we have to filter out SELinux-related xattrs. | |
3361 | */ | |
3362 | if (strcmp(name, XATTR_NAME_SELINUX) == 0) | |
3363 | return 1; /* Discard */ | |
3364 | /* | |
3365 | * Any other attribute apart from SELINUX is not claimed, supported | |
3366 | * by selinux. | |
3367 | */ | |
3368 | return -EOPNOTSUPP; | |
3369 | } | |
3370 | ||
1da177e4 LT |
3371 | /* file security operations */ |
3372 | ||
788e7dd4 | 3373 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3374 | { |
88e67f3b | 3375 | const struct cred *cred = current_cred(); |
496ad9aa | 3376 | struct inode *inode = file_inode(file); |
1da177e4 | 3377 | |
1da177e4 LT |
3378 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3379 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3380 | mask |= MAY_APPEND; | |
3381 | ||
389fb800 PM |
3382 | return file_has_perm(cred, file, |
3383 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3384 | } |
3385 | ||
788e7dd4 YN |
3386 | static int selinux_file_permission(struct file *file, int mask) |
3387 | { | |
496ad9aa | 3388 | struct inode *inode = file_inode(file); |
20dda18b | 3389 | struct file_security_struct *fsec = file->f_security; |
b197367e | 3390 | struct inode_security_struct *isec; |
20dda18b SS |
3391 | u32 sid = current_sid(); |
3392 | ||
389fb800 | 3393 | if (!mask) |
788e7dd4 YN |
3394 | /* No permission to check. Existence test. */ |
3395 | return 0; | |
788e7dd4 | 3396 | |
b197367e | 3397 | isec = inode_security(inode); |
20dda18b SS |
3398 | if (sid == fsec->sid && fsec->isid == isec->sid && |
3399 | fsec->pseqno == avc_policy_seqno()) | |
83d49856 | 3400 | /* No change since file_open check. */ |
20dda18b SS |
3401 | return 0; |
3402 | ||
788e7dd4 YN |
3403 | return selinux_revalidate_file_permission(file, mask); |
3404 | } | |
3405 | ||
1da177e4 LT |
3406 | static int selinux_file_alloc_security(struct file *file) |
3407 | { | |
3408 | return file_alloc_security(file); | |
3409 | } | |
3410 | ||
3411 | static void selinux_file_free_security(struct file *file) | |
3412 | { | |
3413 | file_free_security(file); | |
3414 | } | |
3415 | ||
fa1aa143 JVS |
3416 | /* |
3417 | * Check whether a task has the ioctl permission and cmd | |
3418 | * operation to an inode. | |
3419 | */ | |
1d2a168a | 3420 | static int ioctl_has_perm(const struct cred *cred, struct file *file, |
fa1aa143 JVS |
3421 | u32 requested, u16 cmd) |
3422 | { | |
3423 | struct common_audit_data ad; | |
3424 | struct file_security_struct *fsec = file->f_security; | |
3425 | struct inode *inode = file_inode(file); | |
20cdef8d | 3426 | struct inode_security_struct *isec; |
fa1aa143 JVS |
3427 | struct lsm_ioctlop_audit ioctl; |
3428 | u32 ssid = cred_sid(cred); | |
3429 | int rc; | |
3430 | u8 driver = cmd >> 8; | |
3431 | u8 xperm = cmd & 0xff; | |
3432 | ||
3433 | ad.type = LSM_AUDIT_DATA_IOCTL_OP; | |
3434 | ad.u.op = &ioctl; | |
3435 | ad.u.op->cmd = cmd; | |
3436 | ad.u.op->path = file->f_path; | |
3437 | ||
3438 | if (ssid != fsec->sid) { | |
3439 | rc = avc_has_perm(ssid, fsec->sid, | |
3440 | SECCLASS_FD, | |
3441 | FD__USE, | |
3442 | &ad); | |
3443 | if (rc) | |
3444 | goto out; | |
3445 | } | |
3446 | ||
3447 | if (unlikely(IS_PRIVATE(inode))) | |
3448 | return 0; | |
3449 | ||
20cdef8d | 3450 | isec = inode_security(inode); |
fa1aa143 JVS |
3451 | rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, |
3452 | requested, driver, xperm, &ad); | |
3453 | out: | |
3454 | return rc; | |
3455 | } | |
3456 | ||
1da177e4 LT |
3457 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
3458 | unsigned long arg) | |
3459 | { | |
88e67f3b | 3460 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3461 | int error = 0; |
1da177e4 | 3462 | |
0b24dcb7 EP |
3463 | switch (cmd) { |
3464 | case FIONREAD: | |
3465 | /* fall through */ | |
3466 | case FIBMAP: | |
3467 | /* fall through */ | |
3468 | case FIGETBSZ: | |
3469 | /* fall through */ | |
2f99c369 | 3470 | case FS_IOC_GETFLAGS: |
0b24dcb7 | 3471 | /* fall through */ |
2f99c369 | 3472 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3473 | error = file_has_perm(cred, file, FILE__GETATTR); |
3474 | break; | |
1da177e4 | 3475 | |
2f99c369 | 3476 | case FS_IOC_SETFLAGS: |
0b24dcb7 | 3477 | /* fall through */ |
2f99c369 | 3478 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3479 | error = file_has_perm(cred, file, FILE__SETATTR); |
3480 | break; | |
3481 | ||
3482 | /* sys_ioctl() checks */ | |
3483 | case FIONBIO: | |
3484 | /* fall through */ | |
3485 | case FIOASYNC: | |
3486 | error = file_has_perm(cred, file, 0); | |
3487 | break; | |
1da177e4 | 3488 | |
0b24dcb7 EP |
3489 | case KDSKBENT: |
3490 | case KDSKBSENT: | |
6a9de491 | 3491 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
8e4ff6f2 | 3492 | SECURITY_CAP_AUDIT, true); |
0b24dcb7 EP |
3493 | break; |
3494 | ||
3495 | /* default case assumes that the command will go | |
3496 | * to the file's ioctl() function. | |
3497 | */ | |
3498 | default: | |
fa1aa143 | 3499 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
0b24dcb7 EP |
3500 | } |
3501 | return error; | |
1da177e4 LT |
3502 | } |
3503 | ||
fcaaade1 SS |
3504 | static int default_noexec; |
3505 | ||
1da177e4 LT |
3506 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3507 | { | |
88e67f3b | 3508 | const struct cred *cred = current_cred(); |
be0554c9 | 3509 | u32 sid = cred_sid(cred); |
d84f4f99 | 3510 | int rc = 0; |
88e67f3b | 3511 | |
fcaaade1 | 3512 | if (default_noexec && |
892e8cac SS |
3513 | (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || |
3514 | (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3515 | /* |
3516 | * We are making executable an anonymous mapping or a | |
3517 | * private file mapping that will also be writable. | |
3518 | * This has an additional check. | |
3519 | */ | |
be0554c9 SS |
3520 | rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, |
3521 | PROCESS__EXECMEM, NULL); | |
1da177e4 | 3522 | if (rc) |
d84f4f99 | 3523 | goto error; |
1da177e4 | 3524 | } |
1da177e4 LT |
3525 | |
3526 | if (file) { | |
3527 | /* read access is always possible with a mapping */ | |
3528 | u32 av = FILE__READ; | |
3529 | ||
3530 | /* write access only matters if the mapping is shared */ | |
3531 | if (shared && (prot & PROT_WRITE)) | |
3532 | av |= FILE__WRITE; | |
3533 | ||
3534 | if (prot & PROT_EXEC) | |
3535 | av |= FILE__EXECUTE; | |
3536 | ||
88e67f3b | 3537 | return file_has_perm(cred, file, av); |
1da177e4 | 3538 | } |
d84f4f99 DH |
3539 | |
3540 | error: | |
3541 | return rc; | |
1da177e4 LT |
3542 | } |
3543 | ||
e5467859 | 3544 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3545 | { |
b1d9e6b0 | 3546 | int rc = 0; |
1da177e4 | 3547 | |
a2551df7 | 3548 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
98883bfd | 3549 | u32 sid = current_sid(); |
ed032189 EP |
3550 | rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, |
3551 | MEMPROTECT__MMAP_ZERO, NULL); | |
84336d1a EP |
3552 | } |
3553 | ||
98883bfd | 3554 | return rc; |
e5467859 | 3555 | } |
1da177e4 | 3556 | |
e5467859 AV |
3557 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3558 | unsigned long prot, unsigned long flags) | |
3559 | { | |
3ba4bf5f SS |
3560 | struct common_audit_data ad; |
3561 | int rc; | |
3562 | ||
3563 | if (file) { | |
3564 | ad.type = LSM_AUDIT_DATA_FILE; | |
3565 | ad.u.file = file; | |
3566 | rc = inode_has_perm(current_cred(), file_inode(file), | |
3567 | FILE__MAP, &ad); | |
3568 | if (rc) | |
3569 | return rc; | |
3570 | } | |
3571 | ||
1da177e4 LT |
3572 | if (selinux_checkreqprot) |
3573 | prot = reqprot; | |
3574 | ||
3575 | return file_map_prot_check(file, prot, | |
3576 | (flags & MAP_TYPE) == MAP_SHARED); | |
3577 | } | |
3578 | ||
3579 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3580 | unsigned long reqprot, | |
3581 | unsigned long prot) | |
3582 | { | |
88e67f3b | 3583 | const struct cred *cred = current_cred(); |
be0554c9 | 3584 | u32 sid = cred_sid(cred); |
1da177e4 LT |
3585 | |
3586 | if (selinux_checkreqprot) | |
3587 | prot = reqprot; | |
3588 | ||
fcaaade1 SS |
3589 | if (default_noexec && |
3590 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3591 | int rc = 0; |
db4c9641 SS |
3592 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3593 | vma->vm_end <= vma->vm_mm->brk) { | |
be0554c9 SS |
3594 | rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, |
3595 | PROCESS__EXECHEAP, NULL); | |
db4c9641 | 3596 | } else if (!vma->vm_file && |
c2316dbf SS |
3597 | ((vma->vm_start <= vma->vm_mm->start_stack && |
3598 | vma->vm_end >= vma->vm_mm->start_stack) || | |
d17af505 | 3599 | vma_is_stack_for_current(vma))) { |
be0554c9 SS |
3600 | rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, |
3601 | PROCESS__EXECSTACK, NULL); | |
db4c9641 SS |
3602 | } else if (vma->vm_file && vma->anon_vma) { |
3603 | /* | |
3604 | * We are making executable a file mapping that has | |
3605 | * had some COW done. Since pages might have been | |
3606 | * written, check ability to execute the possibly | |
3607 | * modified content. This typically should only | |
3608 | * occur for text relocations. | |
3609 | */ | |
d84f4f99 | 3610 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3611 | } |