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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> |
1da177e4 LT |
20 | * |
21 | * This program is free software; you can redistribute it and/or modify | |
22 | * it under the terms of the GNU General Public License version 2, | |
828dfe1d | 23 | * as published by the Free Software Foundation. |
1da177e4 LT |
24 | */ |
25 | ||
1da177e4 | 26 | #include <linux/init.h> |
0b24dcb7 | 27 | #include <linux/kd.h> |
1da177e4 | 28 | #include <linux/kernel.h> |
0d094efe | 29 | #include <linux/tracehook.h> |
1da177e4 LT |
30 | #include <linux/errno.h> |
31 | #include <linux/sched.h> | |
3c4ed7bd | 32 | #include <linux/lsm_hooks.h> |
1da177e4 LT |
33 | #include <linux/xattr.h> |
34 | #include <linux/capability.h> | |
35 | #include <linux/unistd.h> | |
36 | #include <linux/mm.h> | |
37 | #include <linux/mman.h> | |
38 | #include <linux/slab.h> | |
39 | #include <linux/pagemap.h> | |
0b24dcb7 | 40 | #include <linux/proc_fs.h> |
1da177e4 | 41 | #include <linux/swap.h> |
1da177e4 LT |
42 | #include <linux/spinlock.h> |
43 | #include <linux/syscalls.h> | |
2a7dba39 | 44 | #include <linux/dcache.h> |
1da177e4 | 45 | #include <linux/file.h> |
9f3acc31 | 46 | #include <linux/fdtable.h> |
1da177e4 LT |
47 | #include <linux/namei.h> |
48 | #include <linux/mount.h> | |
1da177e4 LT |
49 | #include <linux/netfilter_ipv4.h> |
50 | #include <linux/netfilter_ipv6.h> | |
51 | #include <linux/tty.h> | |
52 | #include <net/icmp.h> | |
227b60f5 | 53 | #include <net/ip.h> /* for local_port_range[] */ |
1da177e4 | 54 | #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ |
47180068 | 55 | #include <net/inet_connection_sock.h> |
220deb96 | 56 | #include <net/net_namespace.h> |
d621d35e | 57 | #include <net/netlabel.h> |
f5269710 | 58 | #include <linux/uaccess.h> |
1da177e4 | 59 | #include <asm/ioctls.h> |
60063497 | 60 | #include <linux/atomic.h> |
1da177e4 LT |
61 | #include <linux/bitops.h> |
62 | #include <linux/interrupt.h> | |
63 | #include <linux/netdevice.h> /* for network interface checks */ | |
77954983 | 64 | #include <net/netlink.h> |
1da177e4 LT |
65 | #include <linux/tcp.h> |
66 | #include <linux/udp.h> | |
2ee92d46 | 67 | #include <linux/dccp.h> |
1da177e4 LT |
68 | #include <linux/quota.h> |
69 | #include <linux/un.h> /* for Unix socket types */ | |
70 | #include <net/af_unix.h> /* for Unix socket types */ | |
71 | #include <linux/parser.h> | |
72 | #include <linux/nfs_mount.h> | |
73 | #include <net/ipv6.h> | |
74 | #include <linux/hugetlb.h> | |
75 | #include <linux/personality.h> | |
1da177e4 | 76 | #include <linux/audit.h> |
6931dfc9 | 77 | #include <linux/string.h> |
877ce7c1 | 78 | #include <linux/selinux.h> |
23970741 | 79 | #include <linux/mutex.h> |
f06febc9 | 80 | #include <linux/posix-timers.h> |
00234592 | 81 | #include <linux/syslog.h> |
3486740a | 82 | #include <linux/user_namespace.h> |
44fc7ea0 | 83 | #include <linux/export.h> |
40401530 AV |
84 | #include <linux/msg.h> |
85 | #include <linux/shm.h> | |
1da177e4 LT |
86 | |
87 | #include "avc.h" | |
88 | #include "objsec.h" | |
89 | #include "netif.h" | |
224dfbd8 | 90 | #include "netnode.h" |
3e112172 | 91 | #include "netport.h" |
d28d1e08 | 92 | #include "xfrm.h" |
c60475bf | 93 | #include "netlabel.h" |
9d57a7f9 | 94 | #include "audit.h" |
7b98a585 | 95 | #include "avc_ss.h" |
1da177e4 | 96 | |
d621d35e | 97 | /* SECMARK reference count */ |
56a4ca99 | 98 | static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); |
d621d35e | 99 | |
1da177e4 | 100 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
828dfe1d | 101 | int selinux_enforcing; |
1da177e4 LT |
102 | |
103 | static int __init enforcing_setup(char *str) | |
104 | { | |
f5269710 | 105 | unsigned long enforcing; |
29707b20 | 106 | if (!kstrtoul(str, 0, &enforcing)) |
f5269710 | 107 | selinux_enforcing = enforcing ? 1 : 0; |
1da177e4 LT |
108 | return 1; |
109 | } | |
110 | __setup("enforcing=", enforcing_setup); | |
111 | #endif | |
112 | ||
113 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM | |
114 | int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; | |
115 | ||
116 | static int __init selinux_enabled_setup(char *str) | |
117 | { | |
f5269710 | 118 | unsigned long enabled; |
29707b20 | 119 | if (!kstrtoul(str, 0, &enabled)) |
f5269710 | 120 | selinux_enabled = enabled ? 1 : 0; |
1da177e4 LT |
121 | return 1; |
122 | } | |
123 | __setup("selinux=", selinux_enabled_setup); | |
30d55280 SS |
124 | #else |
125 | int selinux_enabled = 1; | |
1da177e4 LT |
126 | #endif |
127 | ||
e18b890b | 128 | static struct kmem_cache *sel_inode_cache; |
63205654 | 129 | static struct kmem_cache *file_security_cache; |
7cae7e26 | 130 | |
d621d35e PM |
131 | /** |
132 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
133 | * | |
134 | * Description: | |
135 | * This function checks the SECMARK reference counter to see if any SECMARK | |
136 | * targets are currently configured, if the reference counter is greater than | |
137 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
2be4d74f CP |
138 | * enabled, false (0) if SECMARK is disabled. If the always_check_network |
139 | * policy capability is enabled, SECMARK is always considered enabled. | |
d621d35e PM |
140 | * |
141 | */ | |
142 | static int selinux_secmark_enabled(void) | |
143 | { | |
2be4d74f CP |
144 | return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount)); |
145 | } | |
146 | ||
147 | /** | |
148 | * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled | |
149 | * | |
150 | * Description: | |
151 | * This function checks if NetLabel or labeled IPSEC is enabled. Returns true | |
152 | * (1) if any are enabled or false (0) if neither are enabled. If the | |
153 | * always_check_network policy capability is enabled, peer labeling | |
154 | * is always considered enabled. | |
155 | * | |
156 | */ | |
157 | static int selinux_peerlbl_enabled(void) | |
158 | { | |
159 | return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled()); | |
d621d35e PM |
160 | } |
161 | ||
615e51fd PM |
162 | static int selinux_netcache_avc_callback(u32 event) |
163 | { | |
164 | if (event == AVC_CALLBACK_RESET) { | |
165 | sel_netif_flush(); | |
166 | sel_netnode_flush(); | |
167 | sel_netport_flush(); | |
168 | synchronize_net(); | |
169 | } | |
170 | return 0; | |
171 | } | |
172 | ||
d84f4f99 DH |
173 | /* |
174 | * initialise the security for the init task | |
175 | */ | |
176 | static void cred_init_security(void) | |
1da177e4 | 177 | { |
3b11a1de | 178 | struct cred *cred = (struct cred *) current->real_cred; |
1da177e4 LT |
179 | struct task_security_struct *tsec; |
180 | ||
89d155ef | 181 | tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); |
1da177e4 | 182 | if (!tsec) |
d84f4f99 | 183 | panic("SELinux: Failed to initialize initial task.\n"); |
1da177e4 | 184 | |
d84f4f99 | 185 | tsec->osid = tsec->sid = SECINITSID_KERNEL; |
f1752eec | 186 | cred->security = tsec; |
1da177e4 LT |
187 | } |
188 | ||
88e67f3b DH |
189 | /* |
190 | * get the security ID of a set of credentials | |
191 | */ | |
192 | static inline u32 cred_sid(const struct cred *cred) | |
193 | { | |
194 | const struct task_security_struct *tsec; | |
195 | ||
196 | tsec = cred->security; | |
197 | return tsec->sid; | |
198 | } | |
199 | ||
275bb41e | 200 | /* |
3b11a1de | 201 | * get the objective security ID of a task |
275bb41e DH |
202 | */ |
203 | static inline u32 task_sid(const struct task_struct *task) | |
204 | { | |
275bb41e DH |
205 | u32 sid; |
206 | ||
207 | rcu_read_lock(); | |
88e67f3b | 208 | sid = cred_sid(__task_cred(task)); |
275bb41e DH |
209 | rcu_read_unlock(); |
210 | return sid; | |
211 | } | |
212 | ||
213 | /* | |
3b11a1de | 214 | * get the subjective security ID of the current task |
275bb41e DH |
215 | */ |
216 | static inline u32 current_sid(void) | |
217 | { | |
5fb49870 | 218 | const struct task_security_struct *tsec = current_security(); |
275bb41e DH |
219 | |
220 | return tsec->sid; | |
221 | } | |
222 | ||
88e67f3b DH |
223 | /* Allocate and free functions for each kind of security blob. */ |
224 | ||
1da177e4 LT |
225 | static int inode_alloc_security(struct inode *inode) |
226 | { | |
1da177e4 | 227 | struct inode_security_struct *isec; |
275bb41e | 228 | u32 sid = current_sid(); |
1da177e4 | 229 | |
a02fe132 | 230 | isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); |
1da177e4 LT |
231 | if (!isec) |
232 | return -ENOMEM; | |
233 | ||
9287aed2 | 234 | spin_lock_init(&isec->lock); |
1da177e4 | 235 | INIT_LIST_HEAD(&isec->list); |
1da177e4 LT |
236 | isec->inode = inode; |
237 | isec->sid = SECINITSID_UNLABELED; | |
238 | isec->sclass = SECCLASS_FILE; | |
275bb41e | 239 | isec->task_sid = sid; |
42059112 | 240 | isec->initialized = LABEL_INVALID; |
1da177e4 LT |
241 | inode->i_security = isec; |
242 | ||
243 | return 0; | |
244 | } | |
245 | ||
5d226df4 AG |
246 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); |
247 | ||
248 | /* | |
249 | * Try reloading inode security labels that have been marked as invalid. The | |
250 | * @may_sleep parameter indicates when sleeping and thus reloading labels is | |
42059112 | 251 | * allowed; when set to false, returns -ECHILD when the label is |
5d226df4 AG |
252 | * invalid. The @opt_dentry parameter should be set to a dentry of the inode; |
253 | * when no dentry is available, set it to NULL instead. | |
254 | */ | |
255 | static int __inode_security_revalidate(struct inode *inode, | |
256 | struct dentry *opt_dentry, | |
257 | bool may_sleep) | |
258 | { | |
259 | struct inode_security_struct *isec = inode->i_security; | |
260 | ||
261 | might_sleep_if(may_sleep); | |
262 | ||
1ac42476 | 263 | if (ss_initialized && isec->initialized != LABEL_INITIALIZED) { |
5d226df4 AG |
264 | if (!may_sleep) |
265 | return -ECHILD; | |
266 | ||
267 | /* | |
268 | * Try reloading the inode security label. This will fail if | |
269 | * @opt_dentry is NULL and no dentry for this inode can be | |
270 | * found; in that case, continue using the old label. | |
271 | */ | |
272 | inode_doinit_with_dentry(inode, opt_dentry); | |
273 | } | |
274 | return 0; | |
275 | } | |
276 | ||
5d226df4 AG |
277 | static struct inode_security_struct *inode_security_novalidate(struct inode *inode) |
278 | { | |
279 | return inode->i_security; | |
280 | } | |
281 | ||
282 | static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) | |
283 | { | |
284 | int error; | |
285 | ||
286 | error = __inode_security_revalidate(inode, NULL, !rcu); | |
287 | if (error) | |
288 | return ERR_PTR(error); | |
289 | return inode->i_security; | |
290 | } | |
291 | ||
83da53c5 AG |
292 | /* |
293 | * Get the security label of an inode. | |
294 | */ | |
295 | static struct inode_security_struct *inode_security(struct inode *inode) | |
296 | { | |
5d226df4 | 297 | __inode_security_revalidate(inode, NULL, true); |
83da53c5 AG |
298 | return inode->i_security; |
299 | } | |
300 | ||
2c97165b PM |
301 | static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) |
302 | { | |
303 | struct inode *inode = d_backing_inode(dentry); | |
304 | ||
305 | return inode->i_security; | |
306 | } | |
307 | ||
83da53c5 AG |
308 | /* |
309 | * Get the security label of a dentry's backing inode. | |
310 | */ | |
311 | static struct inode_security_struct *backing_inode_security(struct dentry *dentry) | |
312 | { | |
313 | struct inode *inode = d_backing_inode(dentry); | |
314 | ||
5d226df4 | 315 | __inode_security_revalidate(inode, dentry, true); |
83da53c5 AG |
316 | return inode->i_security; |
317 | } | |
318 | ||
3dc91d43 SR |
319 | static void inode_free_rcu(struct rcu_head *head) |
320 | { | |
321 | struct inode_security_struct *isec; | |
322 | ||
323 | isec = container_of(head, struct inode_security_struct, rcu); | |
324 | kmem_cache_free(sel_inode_cache, isec); | |
325 | } | |
326 | ||
1da177e4 LT |
327 | static void inode_free_security(struct inode *inode) |
328 | { | |
329 | struct inode_security_struct *isec = inode->i_security; | |
330 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
331 | ||
9629d04a WL |
332 | /* |
333 | * As not all inode security structures are in a list, we check for | |
334 | * empty list outside of the lock to make sure that we won't waste | |
335 | * time taking a lock doing nothing. | |
336 | * | |
337 | * The list_del_init() function can be safely called more than once. | |
338 | * It should not be possible for this function to be called with | |
339 | * concurrent list_add(), but for better safety against future changes | |
340 | * in the code, we use list_empty_careful() here. | |
341 | */ | |
342 | if (!list_empty_careful(&isec->list)) { | |
343 | spin_lock(&sbsec->isec_lock); | |
1da177e4 | 344 | list_del_init(&isec->list); |
9629d04a WL |
345 | spin_unlock(&sbsec->isec_lock); |
346 | } | |
1da177e4 | 347 | |
3dc91d43 SR |
348 | /* |
349 | * The inode may still be referenced in a path walk and | |
350 | * a call to selinux_inode_permission() can be made | |
351 | * after inode_free_security() is called. Ideally, the VFS | |
352 | * wouldn't do this, but fixing that is a much harder | |
353 | * job. For now, simply free the i_security via RCU, and | |
354 | * leave the current inode->i_security pointer intact. | |
355 | * The inode will be freed after the RCU grace period too. | |
356 | */ | |
357 | call_rcu(&isec->rcu, inode_free_rcu); | |
1da177e4 LT |
358 | } |
359 | ||
360 | static int file_alloc_security(struct file *file) | |
361 | { | |
1da177e4 | 362 | struct file_security_struct *fsec; |
275bb41e | 363 | u32 sid = current_sid(); |
1da177e4 | 364 | |
63205654 | 365 | fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL); |
1da177e4 LT |
366 | if (!fsec) |
367 | return -ENOMEM; | |
368 | ||
275bb41e DH |
369 | fsec->sid = sid; |
370 | fsec->fown_sid = sid; | |
1da177e4 LT |
371 | file->f_security = fsec; |
372 | ||
373 | return 0; | |
374 | } | |
375 | ||
376 | static void file_free_security(struct file *file) | |
377 | { | |
378 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 | 379 | file->f_security = NULL; |
63205654 | 380 | kmem_cache_free(file_security_cache, fsec); |
1da177e4 LT |
381 | } |
382 | ||
383 | static int superblock_alloc_security(struct super_block *sb) | |
384 | { | |
385 | struct superblock_security_struct *sbsec; | |
386 | ||
89d155ef | 387 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
388 | if (!sbsec) |
389 | return -ENOMEM; | |
390 | ||
bc7e982b | 391 | mutex_init(&sbsec->lock); |
1da177e4 LT |
392 | INIT_LIST_HEAD(&sbsec->isec_head); |
393 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
394 | sbsec->sb = sb; |
395 | sbsec->sid = SECINITSID_UNLABELED; | |
396 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 397 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
398 | sb->s_security = sbsec; |
399 | ||
400 | return 0; | |
401 | } | |
402 | ||
403 | static void superblock_free_security(struct super_block *sb) | |
404 | { | |
405 | struct superblock_security_struct *sbsec = sb->s_security; | |
1da177e4 LT |
406 | sb->s_security = NULL; |
407 | kfree(sbsec); | |
408 | } | |
409 | ||
1da177e4 LT |
410 | /* The file system's label must be initialized prior to use. */ |
411 | ||
eb9ae686 | 412 | static const char *labeling_behaviors[7] = { |
1da177e4 LT |
413 | "uses xattr", |
414 | "uses transition SIDs", | |
415 | "uses task SIDs", | |
416 | "uses genfs_contexts", | |
417 | "not configured for labeling", | |
418 | "uses mountpoint labeling", | |
eb9ae686 | 419 | "uses native labeling", |
1da177e4 LT |
420 | }; |
421 | ||
1da177e4 LT |
422 | static inline int inode_doinit(struct inode *inode) |
423 | { | |
424 | return inode_doinit_with_dentry(inode, NULL); | |
425 | } | |
426 | ||
427 | enum { | |
31e87930 | 428 | Opt_error = -1, |
1da177e4 LT |
429 | Opt_context = 1, |
430 | Opt_fscontext = 2, | |
c9180a57 EP |
431 | Opt_defcontext = 3, |
432 | Opt_rootcontext = 4, | |
11689d47 | 433 | Opt_labelsupport = 5, |
d355987f | 434 | Opt_nextmntopt = 6, |
1da177e4 LT |
435 | }; |
436 | ||
d355987f EP |
437 | #define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) |
438 | ||
a447c093 | 439 | static const match_table_t tokens = { |
832cbd9a EP |
440 | {Opt_context, CONTEXT_STR "%s"}, |
441 | {Opt_fscontext, FSCONTEXT_STR "%s"}, | |
442 | {Opt_defcontext, DEFCONTEXT_STR "%s"}, | |
443 | {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, | |
11689d47 | 444 | {Opt_labelsupport, LABELSUPP_STR}, |
31e87930 | 445 | {Opt_error, NULL}, |
1da177e4 LT |
446 | }; |
447 | ||
448 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
449 | ||
c312feb2 EP |
450 | static int may_context_mount_sb_relabel(u32 sid, |
451 | struct superblock_security_struct *sbsec, | |
275bb41e | 452 | const struct cred *cred) |
c312feb2 | 453 | { |
275bb41e | 454 | const struct task_security_struct *tsec = cred->security; |
c312feb2 EP |
455 | int rc; |
456 | ||
457 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
458 | FILESYSTEM__RELABELFROM, NULL); | |
459 | if (rc) | |
460 | return rc; | |
461 | ||
462 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, | |
463 | FILESYSTEM__RELABELTO, NULL); | |
464 | return rc; | |
465 | } | |
466 | ||
0808925e EP |
467 | static int may_context_mount_inode_relabel(u32 sid, |
468 | struct superblock_security_struct *sbsec, | |
275bb41e | 469 | const struct cred *cred) |
0808925e | 470 | { |
275bb41e | 471 | const struct task_security_struct *tsec = cred->security; |
0808925e EP |
472 | int rc; |
473 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
474 | FILESYSTEM__RELABELFROM, NULL); | |
475 | if (rc) | |
476 | return rc; | |
477 | ||
478 | rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
479 | FILESYSTEM__ASSOCIATE, NULL); | |
480 | return rc; | |
481 | } | |
482 | ||
b43e725d EP |
483 | static int selinux_is_sblabel_mnt(struct super_block *sb) |
484 | { | |
485 | struct superblock_security_struct *sbsec = sb->s_security; | |
486 | ||
d5f3a5f6 MS |
487 | return sbsec->behavior == SECURITY_FS_USE_XATTR || |
488 | sbsec->behavior == SECURITY_FS_USE_TRANS || | |
489 | sbsec->behavior == SECURITY_FS_USE_TASK || | |
9fc2b4b4 | 490 | sbsec->behavior == SECURITY_FS_USE_NATIVE || |
d5f3a5f6 MS |
491 | /* Special handling. Genfs but also in-core setxattr handler */ |
492 | !strcmp(sb->s_type->name, "sysfs") || | |
493 | !strcmp(sb->s_type->name, "pstore") || | |
494 | !strcmp(sb->s_type->name, "debugfs") || | |
a2c7c6fb | 495 | !strcmp(sb->s_type->name, "tracefs") || |
d5f3a5f6 | 496 | !strcmp(sb->s_type->name, "rootfs"); |
b43e725d EP |
497 | } |
498 | ||
c9180a57 | 499 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 500 | { |
1da177e4 | 501 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 | 502 | struct dentry *root = sb->s_root; |
c6f493d6 | 503 | struct inode *root_inode = d_backing_inode(root); |
c9180a57 | 504 | int rc = 0; |
1da177e4 | 505 | |
c9180a57 EP |
506 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
507 | /* Make sure that the xattr handler exists and that no | |
508 | error other than -ENODATA is returned by getxattr on | |
509 | the root directory. -ENODATA is ok, as this may be | |
510 | the first boot of the SELinux kernel before we have | |
511 | assigned xattr values to the filesystem. */ | |
5d6c3191 | 512 | if (!(root_inode->i_opflags & IOP_XATTR)) { |
29b1deb2 LT |
513 | printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " |
514 | "xattr support\n", sb->s_id, sb->s_type->name); | |
c9180a57 EP |
515 | rc = -EOPNOTSUPP; |
516 | goto out; | |
517 | } | |
5d6c3191 AG |
518 | |
519 | rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); | |
c9180a57 EP |
520 | if (rc < 0 && rc != -ENODATA) { |
521 | if (rc == -EOPNOTSUPP) | |
522 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
29b1deb2 LT |
523 | "%s) has no security xattr handler\n", |
524 | sb->s_id, sb->s_type->name); | |
c9180a57 EP |
525 | else |
526 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
29b1deb2 LT |
527 | "%s) getxattr errno %d\n", sb->s_id, |
528 | sb->s_type->name, -rc); | |
c9180a57 EP |
529 | goto out; |
530 | } | |
531 | } | |
1da177e4 | 532 | |
c9180a57 | 533 | if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) |
29b1deb2 LT |
534 | printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", |
535 | sb->s_id, sb->s_type->name); | |
1da177e4 | 536 | |
eadcabc6 | 537 | sbsec->flags |= SE_SBINITIALIZED; |
b43e725d | 538 | if (selinux_is_sblabel_mnt(sb)) |
12f348b9 | 539 | sbsec->flags |= SBLABEL_MNT; |
ddd29ec6 | 540 | |
c9180a57 EP |
541 | /* Initialize the root inode. */ |
542 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 543 | |
c9180a57 EP |
544 | /* Initialize any other inodes associated with the superblock, e.g. |
545 | inodes created prior to initial policy load or inodes created | |
546 | during get_sb by a pseudo filesystem that directly | |
547 | populates itself. */ | |
548 | spin_lock(&sbsec->isec_lock); | |
549 | next_inode: | |
550 | if (!list_empty(&sbsec->isec_head)) { | |
551 | struct inode_security_struct *isec = | |
552 | list_entry(sbsec->isec_head.next, | |
553 | struct inode_security_struct, list); | |
554 | struct inode *inode = isec->inode; | |
923190d3 | 555 | list_del_init(&isec->list); |
c9180a57 EP |
556 | spin_unlock(&sbsec->isec_lock); |
557 | inode = igrab(inode); | |
558 | if (inode) { | |
559 | if (!IS_PRIVATE(inode)) | |
560 | inode_doinit(inode); | |
561 | iput(inode); | |
562 | } | |
563 | spin_lock(&sbsec->isec_lock); | |
c9180a57 EP |
564 | goto next_inode; |
565 | } | |
566 | spin_unlock(&sbsec->isec_lock); | |
567 | out: | |
568 | return rc; | |
569 | } | |
1da177e4 | 570 | |
c9180a57 EP |
571 | /* |
572 | * This function should allow an FS to ask what it's mount security | |
573 | * options were so it can use those later for submounts, displaying | |
574 | * mount options, or whatever. | |
575 | */ | |
576 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
e0007529 | 577 | struct security_mnt_opts *opts) |
c9180a57 EP |
578 | { |
579 | int rc = 0, i; | |
580 | struct superblock_security_struct *sbsec = sb->s_security; | |
581 | char *context = NULL; | |
582 | u32 len; | |
583 | char tmp; | |
1da177e4 | 584 | |
e0007529 | 585 | security_init_mnt_opts(opts); |
1da177e4 | 586 | |
0d90a7ec | 587 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
c9180a57 | 588 | return -EINVAL; |
1da177e4 | 589 | |
c9180a57 EP |
590 | if (!ss_initialized) |
591 | return -EINVAL; | |
1da177e4 | 592 | |
af8e50cc EP |
593 | /* make sure we always check enough bits to cover the mask */ |
594 | BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); | |
595 | ||
0d90a7ec | 596 | tmp = sbsec->flags & SE_MNTMASK; |
c9180a57 | 597 | /* count the number of mount options for this sb */ |
af8e50cc | 598 | for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { |
c9180a57 | 599 | if (tmp & 0x01) |
e0007529 | 600 | opts->num_mnt_opts++; |
c9180a57 EP |
601 | tmp >>= 1; |
602 | } | |
11689d47 | 603 | /* Check if the Label support flag is set */ |
0b4bdb35 | 604 | if (sbsec->flags & SBLABEL_MNT) |
11689d47 | 605 | opts->num_mnt_opts++; |
1da177e4 | 606 | |
e0007529 EP |
607 | opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); |
608 | if (!opts->mnt_opts) { | |
c9180a57 EP |
609 | rc = -ENOMEM; |
610 | goto out_free; | |
611 | } | |
1da177e4 | 612 | |
e0007529 EP |
613 | opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); |
614 | if (!opts->mnt_opts_flags) { | |
c9180a57 EP |
615 | rc = -ENOMEM; |
616 | goto out_free; | |
617 | } | |
1da177e4 | 618 | |
c9180a57 EP |
619 | i = 0; |
620 | if (sbsec->flags & FSCONTEXT_MNT) { | |
621 | rc = security_sid_to_context(sbsec->sid, &context, &len); | |
622 | if (rc) | |
623 | goto out_free; | |
e0007529 EP |
624 | opts->mnt_opts[i] = context; |
625 | opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; | |
c9180a57 EP |
626 | } |
627 | if (sbsec->flags & CONTEXT_MNT) { | |
628 | rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); | |
629 | if (rc) | |
630 | goto out_free; | |
e0007529 EP |
631 | opts->mnt_opts[i] = context; |
632 | opts->mnt_opts_flags[i++] = CONTEXT_MNT; | |
c9180a57 EP |
633 | } |
634 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
635 | rc = security_sid_to_context(sbsec->def_sid, &context, &len); | |
636 | if (rc) | |
637 | goto out_free; | |
e0007529 EP |
638 | opts->mnt_opts[i] = context; |
639 | opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
640 | } |
641 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
642 | struct dentry *root = sbsec->sb->s_root; |
643 | struct inode_security_struct *isec = backing_inode_security(root); | |
0808925e | 644 | |
c9180a57 EP |
645 | rc = security_sid_to_context(isec->sid, &context, &len); |
646 | if (rc) | |
647 | goto out_free; | |
e0007529 EP |
648 | opts->mnt_opts[i] = context; |
649 | opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; | |
c9180a57 | 650 | } |
12f348b9 | 651 | if (sbsec->flags & SBLABEL_MNT) { |
11689d47 | 652 | opts->mnt_opts[i] = NULL; |
12f348b9 | 653 | opts->mnt_opts_flags[i++] = SBLABEL_MNT; |
11689d47 | 654 | } |
1da177e4 | 655 | |
e0007529 | 656 | BUG_ON(i != opts->num_mnt_opts); |
1da177e4 | 657 | |
c9180a57 EP |
658 | return 0; |
659 | ||
660 | out_free: | |
e0007529 | 661 | security_free_mnt_opts(opts); |
c9180a57 EP |
662 | return rc; |
663 | } | |
1da177e4 | 664 | |
c9180a57 EP |
665 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
666 | u32 old_sid, u32 new_sid) | |
667 | { | |
0d90a7ec DQ |
668 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
669 | ||
c9180a57 | 670 | /* check if the old mount command had the same options */ |
0d90a7ec | 671 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
672 | if (!(sbsec->flags & flag) || |
673 | (old_sid != new_sid)) | |
674 | return 1; | |
675 | ||
676 | /* check if we were passed the same options twice, | |
677 | * aka someone passed context=a,context=b | |
678 | */ | |
0d90a7ec DQ |
679 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
680 | if (mnt_flags & flag) | |
c9180a57 EP |
681 | return 1; |
682 | return 0; | |
683 | } | |
e0007529 | 684 | |
c9180a57 EP |
685 | /* |
686 | * Allow filesystems with binary mount data to explicitly set mount point | |
687 | * labeling information. | |
688 | */ | |
e0007529 | 689 | static int selinux_set_mnt_opts(struct super_block *sb, |
649f6e77 DQ |
690 | struct security_mnt_opts *opts, |
691 | unsigned long kern_flags, | |
692 | unsigned long *set_kern_flags) | |
c9180a57 | 693 | { |
275bb41e | 694 | const struct cred *cred = current_cred(); |
c9180a57 | 695 | int rc = 0, i; |
c9180a57 | 696 | struct superblock_security_struct *sbsec = sb->s_security; |
29b1deb2 | 697 | const char *name = sb->s_type->name; |
83da53c5 | 698 | struct dentry *root = sbsec->sb->s_root; |
2c97165b | 699 | struct inode_security_struct *root_isec; |
c9180a57 EP |
700 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
701 | u32 defcontext_sid = 0; | |
e0007529 EP |
702 | char **mount_options = opts->mnt_opts; |
703 | int *flags = opts->mnt_opts_flags; | |
704 | int num_opts = opts->num_mnt_opts; | |
c9180a57 EP |
705 | |
706 | mutex_lock(&sbsec->lock); | |
707 | ||
708 | if (!ss_initialized) { | |
709 | if (!num_opts) { | |
710 | /* Defer initialization until selinux_complete_init, | |
711 | after the initial policy is loaded and the security | |
712 | server is ready to handle calls. */ | |
c9180a57 EP |
713 | goto out; |
714 | } | |
715 | rc = -EINVAL; | |
744ba35e EP |
716 | printk(KERN_WARNING "SELinux: Unable to set superblock options " |
717 | "before the security server is initialized\n"); | |
1da177e4 | 718 | goto out; |
c9180a57 | 719 | } |
649f6e77 DQ |
720 | if (kern_flags && !set_kern_flags) { |
721 | /* Specifying internal flags without providing a place to | |
722 | * place the results is not allowed */ | |
723 | rc = -EINVAL; | |
724 | goto out; | |
725 | } | |
1da177e4 | 726 | |
e0007529 EP |
727 | /* |
728 | * Binary mount data FS will come through this function twice. Once | |
729 | * from an explicit call and once from the generic calls from the vfs. | |
730 | * Since the generic VFS calls will not contain any security mount data | |
731 | * we need to skip the double mount verification. | |
732 | * | |
733 | * This does open a hole in which we will not notice if the first | |
734 | * mount using this sb set explict options and a second mount using | |
735 | * this sb does not set any security options. (The first options | |
736 | * will be used for both mounts) | |
737 | */ | |
0d90a7ec | 738 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
e0007529 | 739 | && (num_opts == 0)) |
f5269710 | 740 | goto out; |
e0007529 | 741 | |
2c97165b PM |
742 | root_isec = backing_inode_security_novalidate(root); |
743 | ||
c9180a57 EP |
744 | /* |
745 | * parse the mount options, check if they are valid sids. | |
746 | * also check if someone is trying to mount the same sb more | |
747 | * than once with different security options. | |
748 | */ | |
749 | for (i = 0; i < num_opts; i++) { | |
750 | u32 sid; | |
11689d47 | 751 | |
12f348b9 | 752 | if (flags[i] == SBLABEL_MNT) |
11689d47 | 753 | continue; |
44be2f65 | 754 | rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL); |
1da177e4 | 755 | if (rc) { |
44be2f65 | 756 | printk(KERN_WARNING "SELinux: security_context_str_to_sid" |
29b1deb2 LT |
757 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
758 | mount_options[i], sb->s_id, name, rc); | |
c9180a57 EP |
759 | goto out; |
760 | } | |
761 | switch (flags[i]) { | |
762 | case FSCONTEXT_MNT: | |
763 | fscontext_sid = sid; | |
764 | ||
765 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
766 | fscontext_sid)) | |
767 | goto out_double_mount; | |
768 | ||
769 | sbsec->flags |= FSCONTEXT_MNT; | |
770 | break; | |
771 | case CONTEXT_MNT: | |
772 | context_sid = sid; | |
773 | ||
774 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
775 | context_sid)) | |
776 | goto out_double_mount; | |
777 | ||
778 | sbsec->flags |= CONTEXT_MNT; | |
779 | break; | |
780 | case ROOTCONTEXT_MNT: | |
781 | rootcontext_sid = sid; | |
782 | ||
783 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
784 | rootcontext_sid)) | |
785 | goto out_double_mount; | |
786 | ||
787 | sbsec->flags |= ROOTCONTEXT_MNT; | |
788 | ||
789 | break; | |
790 | case DEFCONTEXT_MNT: | |
791 | defcontext_sid = sid; | |
792 | ||
793 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
794 | defcontext_sid)) | |
795 | goto out_double_mount; | |
796 | ||
797 | sbsec->flags |= DEFCONTEXT_MNT; | |
798 | ||
799 | break; | |
800 | default: | |
801 | rc = -EINVAL; | |
802 | goto out; | |
1da177e4 | 803 | } |
c9180a57 EP |
804 | } |
805 | ||
0d90a7ec | 806 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 807 | /* previously mounted with options, but not on this attempt? */ |
0d90a7ec | 808 | if ((sbsec->flags & SE_MNTMASK) && !num_opts) |
c9180a57 EP |
809 | goto out_double_mount; |
810 | rc = 0; | |
811 | goto out; | |
812 | } | |
813 | ||
089be43e | 814 | if (strcmp(sb->s_type->name, "proc") == 0) |
134509d5 SS |
815 | sbsec->flags |= SE_SBPROC | SE_SBGENFS; |
816 | ||
8e014720 SS |
817 | if (!strcmp(sb->s_type->name, "debugfs") || |
818 | !strcmp(sb->s_type->name, "sysfs") || | |
819 | !strcmp(sb->s_type->name, "pstore")) | |
134509d5 | 820 | sbsec->flags |= SE_SBGENFS; |
c9180a57 | 821 | |
eb9ae686 DQ |
822 | if (!sbsec->behavior) { |
823 | /* | |
824 | * Determine the labeling behavior to use for this | |
825 | * filesystem type. | |
826 | */ | |
98f700f3 | 827 | rc = security_fs_use(sb); |
eb9ae686 DQ |
828 | if (rc) { |
829 | printk(KERN_WARNING | |
830 | "%s: security_fs_use(%s) returned %d\n", | |
831 | __func__, sb->s_type->name, rc); | |
832 | goto out; | |
833 | } | |
c9180a57 | 834 | } |
aad82892 SF |
835 | |
836 | /* | |
837 | * If this is a user namespace mount, no contexts are allowed | |
838 | * on the command line and security labels must be ignored. | |
839 | */ | |
840 | if (sb->s_user_ns != &init_user_ns) { | |
841 | if (context_sid || fscontext_sid || rootcontext_sid || | |
842 | defcontext_sid) { | |
843 | rc = -EACCES; | |
844 | goto out; | |
845 | } | |
846 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { | |
847 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; | |
848 | rc = security_transition_sid(current_sid(), current_sid(), | |
849 | SECCLASS_FILE, NULL, | |
850 | &sbsec->mntpoint_sid); | |
851 | if (rc) | |
852 | goto out; | |
853 | } | |
854 | goto out_set_opts; | |
855 | } | |
856 | ||
c9180a57 EP |
857 | /* sets the context of the superblock for the fs being mounted. */ |
858 | if (fscontext_sid) { | |
275bb41e | 859 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
1da177e4 | 860 | if (rc) |
c9180a57 | 861 | goto out; |
1da177e4 | 862 | |
c9180a57 | 863 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
864 | } |
865 | ||
866 | /* | |
867 | * Switch to using mount point labeling behavior. | |
868 | * sets the label used on all file below the mountpoint, and will set | |
869 | * the superblock context if not already set. | |
870 | */ | |
eb9ae686 DQ |
871 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { |
872 | sbsec->behavior = SECURITY_FS_USE_NATIVE; | |
873 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
874 | } | |
875 | ||
c9180a57 EP |
876 | if (context_sid) { |
877 | if (!fscontext_sid) { | |
275bb41e DH |
878 | rc = may_context_mount_sb_relabel(context_sid, sbsec, |
879 | cred); | |
b04ea3ce | 880 | if (rc) |
c9180a57 EP |
881 | goto out; |
882 | sbsec->sid = context_sid; | |
b04ea3ce | 883 | } else { |
275bb41e DH |
884 | rc = may_context_mount_inode_relabel(context_sid, sbsec, |
885 | cred); | |
b04ea3ce | 886 | if (rc) |
c9180a57 | 887 | goto out; |
b04ea3ce | 888 | } |
c9180a57 EP |
889 | if (!rootcontext_sid) |
890 | rootcontext_sid = context_sid; | |
1da177e4 | 891 | |
c9180a57 | 892 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 893 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
894 | } |
895 | ||
c9180a57 | 896 | if (rootcontext_sid) { |
275bb41e DH |
897 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
898 | cred); | |
0808925e | 899 | if (rc) |
c9180a57 | 900 | goto out; |
0808925e | 901 | |
c9180a57 | 902 | root_isec->sid = rootcontext_sid; |
6f3be9f5 | 903 | root_isec->initialized = LABEL_INITIALIZED; |
0808925e EP |
904 | } |
905 | ||
c9180a57 | 906 | if (defcontext_sid) { |
eb9ae686 DQ |
907 | if (sbsec->behavior != SECURITY_FS_USE_XATTR && |
908 | sbsec->behavior != SECURITY_FS_USE_NATIVE) { | |
c9180a57 EP |
909 | rc = -EINVAL; |
910 | printk(KERN_WARNING "SELinux: defcontext option is " | |
911 | "invalid for this filesystem type\n"); | |
912 | goto out; | |
1da177e4 LT |
913 | } |
914 | ||
c9180a57 EP |
915 | if (defcontext_sid != sbsec->def_sid) { |
916 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
275bb41e | 917 | sbsec, cred); |
c9180a57 EP |
918 | if (rc) |
919 | goto out; | |
920 | } | |
1da177e4 | 921 | |
c9180a57 | 922 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
923 | } |
924 | ||
aad82892 | 925 | out_set_opts: |
c9180a57 | 926 | rc = sb_finish_set_opts(sb); |
1da177e4 | 927 | out: |
c9180a57 | 928 | mutex_unlock(&sbsec->lock); |
1da177e4 | 929 | return rc; |
c9180a57 EP |
930 | out_double_mount: |
931 | rc = -EINVAL; | |
932 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " | |
29b1deb2 | 933 | "security settings for (dev %s, type %s)\n", sb->s_id, name); |
c9180a57 | 934 | goto out; |
1da177e4 LT |
935 | } |
936 | ||
094f7b69 JL |
937 | static int selinux_cmp_sb_context(const struct super_block *oldsb, |
938 | const struct super_block *newsb) | |
939 | { | |
940 | struct superblock_security_struct *old = oldsb->s_security; | |
941 | struct superblock_security_struct *new = newsb->s_security; | |
942 | char oldflags = old->flags & SE_MNTMASK; | |
943 | char newflags = new->flags & SE_MNTMASK; | |
944 | ||
945 | if (oldflags != newflags) | |
946 | goto mismatch; | |
947 | if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) | |
948 | goto mismatch; | |
949 | if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) | |
950 | goto mismatch; | |
951 | if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) | |
952 | goto mismatch; | |
953 | if (oldflags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
954 | struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); |
955 | struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); | |
094f7b69 JL |
956 | if (oldroot->sid != newroot->sid) |
957 | goto mismatch; | |
958 | } | |
959 | return 0; | |
960 | mismatch: | |
961 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " | |
962 | "different security settings for (dev %s, " | |
963 | "type %s)\n", newsb->s_id, newsb->s_type->name); | |
964 | return -EBUSY; | |
965 | } | |
966 | ||
967 | static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, | |
c9180a57 | 968 | struct super_block *newsb) |
1da177e4 | 969 | { |
c9180a57 EP |
970 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
971 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 972 | |
c9180a57 EP |
973 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
974 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
975 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 976 | |
0f5e6420 EP |
977 | /* |
978 | * if the parent was able to be mounted it clearly had no special lsm | |
e8c26255 | 979 | * mount options. thus we can safely deal with this superblock later |
0f5e6420 | 980 | */ |
e8c26255 | 981 | if (!ss_initialized) |
094f7b69 | 982 | return 0; |
c9180a57 | 983 | |
c9180a57 | 984 | /* how can we clone if the old one wasn't set up?? */ |
0d90a7ec | 985 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
c9180a57 | 986 | |
094f7b69 | 987 | /* if fs is reusing a sb, make sure that the contexts match */ |
0d90a7ec | 988 | if (newsbsec->flags & SE_SBINITIALIZED) |
094f7b69 | 989 | return selinux_cmp_sb_context(oldsb, newsb); |
5a552617 | 990 | |
c9180a57 EP |
991 | mutex_lock(&newsbsec->lock); |
992 | ||
993 | newsbsec->flags = oldsbsec->flags; | |
994 | ||
995 | newsbsec->sid = oldsbsec->sid; | |
996 | newsbsec->def_sid = oldsbsec->def_sid; | |
997 | newsbsec->behavior = oldsbsec->behavior; | |
998 | ||
999 | if (set_context) { | |
1000 | u32 sid = oldsbsec->mntpoint_sid; | |
1001 | ||
1002 | if (!set_fscontext) | |
1003 | newsbsec->sid = sid; | |
1004 | if (!set_rootcontext) { | |
83da53c5 | 1005 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); |
c9180a57 EP |
1006 | newisec->sid = sid; |
1007 | } | |
1008 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 1009 | } |
c9180a57 | 1010 | if (set_rootcontext) { |
83da53c5 AG |
1011 | const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); |
1012 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); | |
1da177e4 | 1013 | |
c9180a57 | 1014 | newisec->sid = oldisec->sid; |
1da177e4 LT |
1015 | } |
1016 | ||
c9180a57 EP |
1017 | sb_finish_set_opts(newsb); |
1018 | mutex_unlock(&newsbsec->lock); | |
094f7b69 | 1019 | return 0; |
c9180a57 EP |
1020 | } |
1021 | ||
2e1479d9 AB |
1022 | static int selinux_parse_opts_str(char *options, |
1023 | struct security_mnt_opts *opts) | |
c9180a57 | 1024 | { |
e0007529 | 1025 | char *p; |
c9180a57 EP |
1026 | char *context = NULL, *defcontext = NULL; |
1027 | char *fscontext = NULL, *rootcontext = NULL; | |
e0007529 | 1028 | int rc, num_mnt_opts = 0; |
1da177e4 | 1029 | |
e0007529 | 1030 | opts->num_mnt_opts = 0; |
1da177e4 | 1031 | |
c9180a57 EP |
1032 | /* Standard string-based options. */ |
1033 | while ((p = strsep(&options, "|")) != NULL) { | |
1034 | int token; | |
1035 | substring_t args[MAX_OPT_ARGS]; | |
1da177e4 | 1036 | |
c9180a57 EP |
1037 | if (!*p) |
1038 | continue; | |
1da177e4 | 1039 | |
c9180a57 | 1040 | token = match_token(p, tokens, args); |
1da177e4 | 1041 | |
c9180a57 EP |
1042 | switch (token) { |
1043 | case Opt_context: | |
1044 | if (context || defcontext) { | |
1045 | rc = -EINVAL; | |
1046 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1047 | goto out_err; | |
1048 | } | |
1049 | context = match_strdup(&args[0]); | |
1050 | if (!context) { | |
1051 | rc = -ENOMEM; | |
1052 | goto out_err; | |
1053 | } | |
1054 | break; | |
1055 | ||
1056 | case Opt_fscontext: | |
1057 | if (fscontext) { | |
1058 | rc = -EINVAL; | |
1059 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1060 | goto out_err; | |
1061 | } | |
1062 | fscontext = match_strdup(&args[0]); | |
1063 | if (!fscontext) { | |
1064 | rc = -ENOMEM; | |
1065 | goto out_err; | |
1066 | } | |
1067 | break; | |
1068 | ||
1069 | case Opt_rootcontext: | |
1070 | if (rootcontext) { | |
1071 | rc = -EINVAL; | |
1072 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1073 | goto out_err; | |
1074 | } | |
1075 | rootcontext = match_strdup(&args[0]); | |
1076 | if (!rootcontext) { | |
1077 | rc = -ENOMEM; | |
1078 | goto out_err; | |
1079 | } | |
1080 | break; | |
1081 | ||
1082 | case Opt_defcontext: | |
1083 | if (context || defcontext) { | |
1084 | rc = -EINVAL; | |
1085 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1086 | goto out_err; | |
1087 | } | |
1088 | defcontext = match_strdup(&args[0]); | |
1089 | if (!defcontext) { | |
1090 | rc = -ENOMEM; | |
1091 | goto out_err; | |
1092 | } | |
1093 | break; | |
11689d47 DQ |
1094 | case Opt_labelsupport: |
1095 | break; | |
c9180a57 EP |
1096 | default: |
1097 | rc = -EINVAL; | |
1098 | printk(KERN_WARNING "SELinux: unknown mount option\n"); | |
1099 | goto out_err; | |
1da177e4 | 1100 | |
1da177e4 | 1101 | } |
1da177e4 | 1102 | } |
c9180a57 | 1103 | |
e0007529 | 1104 | rc = -ENOMEM; |
8931c3bd | 1105 | opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL); |
e0007529 EP |
1106 | if (!opts->mnt_opts) |
1107 | goto out_err; | |
1108 | ||
8931c3bd TH |
1109 | opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), |
1110 | GFP_KERNEL); | |
e0007529 EP |
1111 | if (!opts->mnt_opts_flags) { |
1112 | kfree(opts->mnt_opts); | |
1113 | goto out_err; | |
1114 | } | |
1115 | ||
c9180a57 | 1116 | if (fscontext) { |
e0007529 EP |
1117 | opts->mnt_opts[num_mnt_opts] = fscontext; |
1118 | opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; | |
c9180a57 EP |
1119 | } |
1120 | if (context) { | |
e0007529 EP |
1121 | opts->mnt_opts[num_mnt_opts] = context; |
1122 | opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; | |
c9180a57 EP |
1123 | } |
1124 | if (rootcontext) { | |
e0007529 EP |
1125 | opts->mnt_opts[num_mnt_opts] = rootcontext; |
1126 | opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; | |
c9180a57 EP |
1127 | } |
1128 | if (defcontext) { | |
e0007529 EP |
1129 | opts->mnt_opts[num_mnt_opts] = defcontext; |
1130 | opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
1131 | } |
1132 | ||
e0007529 EP |
1133 | opts->num_mnt_opts = num_mnt_opts; |
1134 | return 0; | |
1135 | ||
c9180a57 EP |
1136 | out_err: |
1137 | kfree(context); | |
1138 | kfree(defcontext); | |
1139 | kfree(fscontext); | |
1140 | kfree(rootcontext); | |
1da177e4 LT |
1141 | return rc; |
1142 | } | |
e0007529 EP |
1143 | /* |
1144 | * string mount options parsing and call set the sbsec | |
1145 | */ | |
1146 | static int superblock_doinit(struct super_block *sb, void *data) | |
1147 | { | |
1148 | int rc = 0; | |
1149 | char *options = data; | |
1150 | struct security_mnt_opts opts; | |
1151 | ||
1152 | security_init_mnt_opts(&opts); | |
1153 | ||
1154 | if (!data) | |
1155 | goto out; | |
1156 | ||
1157 | BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); | |
1158 | ||
1159 | rc = selinux_parse_opts_str(options, &opts); | |
1160 | if (rc) | |
1161 | goto out_err; | |
1162 | ||
1163 | out: | |
649f6e77 | 1164 | rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); |
e0007529 EP |
1165 | |
1166 | out_err: | |
1167 | security_free_mnt_opts(&opts); | |
1168 | return rc; | |
1169 | } | |
1da177e4 | 1170 | |
3583a711 AB |
1171 | static void selinux_write_opts(struct seq_file *m, |
1172 | struct security_mnt_opts *opts) | |
2069f457 EP |
1173 | { |
1174 | int i; | |
1175 | char *prefix; | |
1176 | ||
1177 | for (i = 0; i < opts->num_mnt_opts; i++) { | |
11689d47 DQ |
1178 | char *has_comma; |
1179 | ||
1180 | if (opts->mnt_opts[i]) | |
1181 | has_comma = strchr(opts->mnt_opts[i], ','); | |
1182 | else | |
1183 | has_comma = NULL; | |
2069f457 EP |
1184 | |
1185 | switch (opts->mnt_opts_flags[i]) { | |
1186 | case CONTEXT_MNT: | |
1187 | prefix = CONTEXT_STR; | |
1188 | break; | |
1189 | case FSCONTEXT_MNT: | |
1190 | prefix = FSCONTEXT_STR; | |
1191 | break; | |
1192 | case ROOTCONTEXT_MNT: | |
1193 | prefix = ROOTCONTEXT_STR; | |
1194 | break; | |
1195 | case DEFCONTEXT_MNT: | |
1196 | prefix = DEFCONTEXT_STR; | |
1197 | break; | |
12f348b9 | 1198 | case SBLABEL_MNT: |
11689d47 DQ |
1199 | seq_putc(m, ','); |
1200 | seq_puts(m, LABELSUPP_STR); | |
1201 | continue; | |
2069f457 EP |
1202 | default: |
1203 | BUG(); | |
a35c6c83 | 1204 | return; |
2069f457 EP |
1205 | }; |
1206 | /* we need a comma before each option */ | |
1207 | seq_putc(m, ','); | |
1208 | seq_puts(m, prefix); | |
1209 | if (has_comma) | |
1210 | seq_putc(m, '\"'); | |
a068acf2 | 1211 | seq_escape(m, opts->mnt_opts[i], "\"\n\\"); |
2069f457 EP |
1212 | if (has_comma) |
1213 | seq_putc(m, '\"'); | |
1214 | } | |
1215 | } | |
1216 | ||
1217 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1218 | { | |
1219 | struct security_mnt_opts opts; | |
1220 | int rc; | |
1221 | ||
1222 | rc = selinux_get_mnt_opts(sb, &opts); | |
383795c2 EP |
1223 | if (rc) { |
1224 | /* before policy load we may get EINVAL, don't show anything */ | |
1225 | if (rc == -EINVAL) | |
1226 | rc = 0; | |
2069f457 | 1227 | return rc; |
383795c2 | 1228 | } |
2069f457 EP |
1229 | |
1230 | selinux_write_opts(m, &opts); | |
1231 | ||
1232 | security_free_mnt_opts(&opts); | |
1233 | ||
1234 | return rc; | |
1235 | } | |
1236 | ||
1da177e4 LT |
1237 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1238 | { | |
1239 | switch (mode & S_IFMT) { | |
1240 | case S_IFSOCK: | |
1241 | return SECCLASS_SOCK_FILE; | |
1242 | case S_IFLNK: | |
1243 | return SECCLASS_LNK_FILE; | |
1244 | case S_IFREG: | |
1245 | return SECCLASS_FILE; | |
1246 | case S_IFBLK: | |
1247 | return SECCLASS_BLK_FILE; | |
1248 | case S_IFDIR: | |
1249 | return SECCLASS_DIR; | |
1250 | case S_IFCHR: | |
1251 | return SECCLASS_CHR_FILE; | |
1252 | case S_IFIFO: | |
1253 | return SECCLASS_FIFO_FILE; | |
1254 | ||
1255 | } | |
1256 | ||
1257 | return SECCLASS_FILE; | |
1258 | } | |
1259 | ||
13402580 JM |
1260 | static inline int default_protocol_stream(int protocol) |
1261 | { | |
1262 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1263 | } | |
1264 | ||
1265 | static inline int default_protocol_dgram(int protocol) | |
1266 | { | |
1267 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1268 | } | |
1269 | ||
1da177e4 LT |
1270 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1271 | { | |
da69a530 SS |
1272 | int extsockclass = selinux_policycap_extsockclass; |
1273 | ||
1da177e4 LT |
1274 | switch (family) { |
1275 | case PF_UNIX: | |
1276 | switch (type) { | |
1277 | case SOCK_STREAM: | |
1278 | case SOCK_SEQPACKET: | |
1279 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1280 | case SOCK_DGRAM: | |
1281 | return SECCLASS_UNIX_DGRAM_SOCKET; | |
1282 | } | |
1283 | break; | |
1284 | case PF_INET: | |
1285 | case PF_INET6: | |
1286 | switch (type) { | |
1287 | case SOCK_STREAM: | |
da69a530 | 1288 | case SOCK_SEQPACKET: |
13402580 JM |
1289 | if (default_protocol_stream(protocol)) |
1290 | return SECCLASS_TCP_SOCKET; | |
da69a530 SS |
1291 | else if (extsockclass && protocol == IPPROTO_SCTP) |
1292 | return SECCLASS_SCTP_SOCKET; | |
13402580 JM |
1293 | else |
1294 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1295 | case SOCK_DGRAM: |
13402580 JM |
1296 | if (default_protocol_dgram(protocol)) |
1297 | return SECCLASS_UDP_SOCKET; | |
ef37979a SS |
1298 | else if (extsockclass && (protocol == IPPROTO_ICMP || |
1299 | protocol == IPPROTO_ICMPV6)) | |
da69a530 | 1300 | return SECCLASS_ICMP_SOCKET; |
13402580 JM |
1301 | else |
1302 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1303 | case SOCK_DCCP: |
1304 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1305 | default: |
1da177e4 LT |
1306 | return SECCLASS_RAWIP_SOCKET; |
1307 | } | |
1308 | break; | |
1309 | case PF_NETLINK: | |
1310 | switch (protocol) { | |
1311 | case NETLINK_ROUTE: | |
1312 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
7f1fb60c | 1313 | case NETLINK_SOCK_DIAG: |
1da177e4 LT |
1314 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1315 | case NETLINK_NFLOG: | |
1316 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1317 | case NETLINK_XFRM: | |
1318 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1319 | case NETLINK_SELINUX: | |
1320 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
6c6d2e9b SS |
1321 | case NETLINK_ISCSI: |
1322 | return SECCLASS_NETLINK_ISCSI_SOCKET; | |
1da177e4 LT |
1323 | case NETLINK_AUDIT: |
1324 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
6c6d2e9b SS |
1325 | case NETLINK_FIB_LOOKUP: |
1326 | return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; | |
1327 | case NETLINK_CONNECTOR: | |
1328 | return SECCLASS_NETLINK_CONNECTOR_SOCKET; | |
1329 | case NETLINK_NETFILTER: | |
1330 | return SECCLASS_NETLINK_NETFILTER_SOCKET; | |
1da177e4 LT |
1331 | case NETLINK_DNRTMSG: |
1332 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1333 | case NETLINK_KOBJECT_UEVENT: |
1334 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
6c6d2e9b SS |
1335 | case NETLINK_GENERIC: |
1336 | return SECCLASS_NETLINK_GENERIC_SOCKET; | |
1337 | case NETLINK_SCSITRANSPORT: | |
1338 | return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; | |
1339 | case NETLINK_RDMA: | |
1340 | return SECCLASS_NETLINK_RDMA_SOCKET; | |
1341 | case NETLINK_CRYPTO: | |
1342 | return SECCLASS_NETLINK_CRYPTO_SOCKET; | |
1da177e4 LT |
1343 | default: |
1344 | return SECCLASS_NETLINK_SOCKET; | |
1345 | } | |
1346 | case PF_PACKET: | |
1347 | return SECCLASS_PACKET_SOCKET; | |
1348 | case PF_KEY: | |
1349 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1350 | case PF_APPLETALK: |
1351 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1352 | } |
1353 | ||
da69a530 SS |
1354 | if (extsockclass) { |
1355 | switch (family) { | |
1356 | case PF_AX25: | |
1357 | return SECCLASS_AX25_SOCKET; | |
1358 | case PF_IPX: | |
1359 | return SECCLASS_IPX_SOCKET; | |
1360 | case PF_NETROM: | |
1361 | return SECCLASS_NETROM_SOCKET; | |
1362 | case PF_BRIDGE: | |
1363 | return SECCLASS_BRIDGE_SOCKET; | |
1364 | case PF_ATMPVC: | |
1365 | return SECCLASS_ATMPVC_SOCKET; | |
1366 | case PF_X25: | |
1367 | return SECCLASS_X25_SOCKET; | |
1368 | case PF_ROSE: | |
1369 | return SECCLASS_ROSE_SOCKET; | |
1370 | case PF_DECnet: | |
1371 | return SECCLASS_DECNET_SOCKET; | |
1372 | case PF_ATMSVC: | |
1373 | return SECCLASS_ATMSVC_SOCKET; | |
1374 | case PF_RDS: | |
1375 | return SECCLASS_RDS_SOCKET; | |
1376 | case PF_IRDA: | |
1377 | return SECCLASS_IRDA_SOCKET; | |
1378 | case PF_PPPOX: | |
1379 | return SECCLASS_PPPOX_SOCKET; | |
1380 | case PF_LLC: | |
1381 | return SECCLASS_LLC_SOCKET; | |
1382 | case PF_IB: | |
1383 | return SECCLASS_IB_SOCKET; | |
1384 | case PF_MPLS: | |
1385 | return SECCLASS_MPLS_SOCKET; | |
1386 | case PF_CAN: | |
1387 | return SECCLASS_CAN_SOCKET; | |
1388 | case PF_TIPC: | |
1389 | return SECCLASS_TIPC_SOCKET; | |
1390 | case PF_BLUETOOTH: | |
1391 | return SECCLASS_BLUETOOTH_SOCKET; | |
1392 | case PF_IUCV: | |
1393 | return SECCLASS_IUCV_SOCKET; | |
1394 | case PF_RXRPC: | |
1395 | return SECCLASS_RXRPC_SOCKET; | |
1396 | case PF_ISDN: | |
1397 | return SECCLASS_ISDN_SOCKET; | |
1398 | case PF_PHONET: | |
1399 | return SECCLASS_PHONET_SOCKET; | |
1400 | case PF_IEEE802154: | |
1401 | return SECCLASS_IEEE802154_SOCKET; | |
1402 | case PF_CAIF: | |
1403 | return SECCLASS_CAIF_SOCKET; | |
1404 | case PF_ALG: | |
1405 | return SECCLASS_ALG_SOCKET; | |
1406 | case PF_NFC: | |
1407 | return SECCLASS_NFC_SOCKET; | |
1408 | case PF_VSOCK: | |
1409 | return SECCLASS_VSOCK_SOCKET; | |
1410 | case PF_KCM: | |
1411 | return SECCLASS_KCM_SOCKET; | |
1412 | case PF_QIPCRTR: | |
1413 | return SECCLASS_QIPCRTR_SOCKET; | |
1414 | #if PF_MAX > 43 | |
1415 | #error New address family defined, please update this function. | |
1416 | #endif | |
1417 | } | |
1418 | } | |
1419 | ||
1da177e4 LT |
1420 | return SECCLASS_SOCKET; |
1421 | } | |
1422 | ||
134509d5 SS |
1423 | static int selinux_genfs_get_sid(struct dentry *dentry, |
1424 | u16 tclass, | |
1425 | u16 flags, | |
1426 | u32 *sid) | |
1da177e4 | 1427 | { |
8e6c9693 | 1428 | int rc; |
fc64005c | 1429 | struct super_block *sb = dentry->d_sb; |
8e6c9693 | 1430 | char *buffer, *path; |
1da177e4 | 1431 | |
828dfe1d | 1432 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1433 | if (!buffer) |
1434 | return -ENOMEM; | |
1435 | ||
8e6c9693 LAG |
1436 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1437 | if (IS_ERR(path)) | |
1438 | rc = PTR_ERR(path); | |
1439 | else { | |
134509d5 SS |
1440 | if (flags & SE_SBPROC) { |
1441 | /* each process gets a /proc/PID/ entry. Strip off the | |
1442 | * PID part to get a valid selinux labeling. | |
1443 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1444 | while (path[1] >= '0' && path[1] <= '9') { | |
1445 | path[1] = '/'; | |
1446 | path++; | |
1447 | } | |
8e6c9693 | 1448 | } |
134509d5 | 1449 | rc = security_genfs_sid(sb->s_type->name, path, tclass, sid); |
1da177e4 | 1450 | } |
1da177e4 LT |
1451 | free_page((unsigned long)buffer); |
1452 | return rc; | |
1453 | } | |
1da177e4 LT |
1454 | |
1455 | /* The inode's security attributes must be initialized before first use. */ | |
1456 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1457 | { | |
1458 | struct superblock_security_struct *sbsec = NULL; | |
1459 | struct inode_security_struct *isec = inode->i_security; | |
9287aed2 AG |
1460 | u32 task_sid, sid = 0; |
1461 | u16 sclass; | |
1da177e4 LT |
1462 | struct dentry *dentry; |
1463 | #define INITCONTEXTLEN 255 | |
1464 | char *context = NULL; | |
1465 | unsigned len = 0; | |
1466 | int rc = 0; | |
1da177e4 | 1467 | |
6f3be9f5 | 1468 | if (isec->initialized == LABEL_INITIALIZED) |
13457d07 | 1469 | return 0; |
1da177e4 | 1470 | |
9287aed2 | 1471 | spin_lock(&isec->lock); |
6f3be9f5 | 1472 | if (isec->initialized == LABEL_INITIALIZED) |
23970741 | 1473 | goto out_unlock; |
1da177e4 | 1474 | |
13457d07 AG |
1475 | if (isec->sclass == SECCLASS_FILE) |
1476 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1477 | ||
1da177e4 | 1478 | sbsec = inode->i_sb->s_security; |
0d90a7ec | 1479 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1480 | /* Defer initialization until selinux_complete_init, |
1481 | after the initial policy is loaded and the security | |
1482 | server is ready to handle calls. */ | |
1483 | spin_lock(&sbsec->isec_lock); | |
1484 | if (list_empty(&isec->list)) | |
1485 | list_add(&isec->list, &sbsec->isec_head); | |
1486 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1487 | goto out_unlock; |
1da177e4 LT |
1488 | } |
1489 | ||
9287aed2 AG |
1490 | sclass = isec->sclass; |
1491 | task_sid = isec->task_sid; | |
1492 | sid = isec->sid; | |
1493 | isec->initialized = LABEL_PENDING; | |
1494 | spin_unlock(&isec->lock); | |
1495 | ||
1da177e4 | 1496 | switch (sbsec->behavior) { |
eb9ae686 DQ |
1497 | case SECURITY_FS_USE_NATIVE: |
1498 | break; | |
1da177e4 | 1499 | case SECURITY_FS_USE_XATTR: |
5d6c3191 | 1500 | if (!(inode->i_opflags & IOP_XATTR)) { |
9287aed2 | 1501 | sid = sbsec->def_sid; |
1da177e4 LT |
1502 | break; |
1503 | } | |
1da177e4 LT |
1504 | /* Need a dentry, since the xattr API requires one. |
1505 | Life would be simpler if we could just pass the inode. */ | |
1506 | if (opt_dentry) { | |
1507 | /* Called from d_instantiate or d_splice_alias. */ | |
1508 | dentry = dget(opt_dentry); | |
1509 | } else { | |
1510 | /* Called from selinux_complete_init, try to find a dentry. */ | |
1511 | dentry = d_find_alias(inode); | |
1512 | } | |
1513 | if (!dentry) { | |
df7f54c0 EP |
1514 | /* |
1515 | * this is can be hit on boot when a file is accessed | |
1516 | * before the policy is loaded. When we load policy we | |
1517 | * may find inodes that have no dentry on the | |
1518 | * sbsec->isec_head list. No reason to complain as these | |
1519 | * will get fixed up the next time we go through | |
1520 | * inode_doinit with a dentry, before these inodes could | |
1521 | * be used again by userspace. | |
1522 | */ | |
9287aed2 | 1523 | goto out; |
1da177e4 LT |
1524 | } |
1525 | ||
1526 | len = INITCONTEXTLEN; | |
4cb912f1 | 1527 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1528 | if (!context) { |
1529 | rc = -ENOMEM; | |
1530 | dput(dentry); | |
9287aed2 | 1531 | goto out; |
1da177e4 | 1532 | } |
4cb912f1 | 1533 | context[len] = '\0'; |
5d6c3191 | 1534 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); |
1da177e4 | 1535 | if (rc == -ERANGE) { |
314dabb8 JM |
1536 | kfree(context); |
1537 | ||
1da177e4 | 1538 | /* Need a larger buffer. Query for the right size. */ |
5d6c3191 | 1539 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); |
1da177e4 LT |
1540 | if (rc < 0) { |
1541 | dput(dentry); | |
9287aed2 | 1542 | goto out; |
1da177e4 | 1543 | } |
1da177e4 | 1544 | len = rc; |
4cb912f1 | 1545 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1546 | if (!context) { |
1547 | rc = -ENOMEM; | |
1548 | dput(dentry); | |
9287aed2 | 1549 | goto out; |
1da177e4 | 1550 | } |
4cb912f1 | 1551 | context[len] = '\0'; |
5d6c3191 | 1552 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); |
1da177e4 LT |
1553 | } |
1554 | dput(dentry); | |
1555 | if (rc < 0) { | |
1556 | if (rc != -ENODATA) { | |
744ba35e | 1557 | printk(KERN_WARNING "SELinux: %s: getxattr returned " |
dd6f953a | 1558 | "%d for dev=%s ino=%ld\n", __func__, |
1da177e4 LT |
1559 | -rc, inode->i_sb->s_id, inode->i_ino); |
1560 | kfree(context); | |
9287aed2 | 1561 | goto out; |
1da177e4 LT |
1562 | } |
1563 | /* Map ENODATA to the default file SID */ | |
1564 | sid = sbsec->def_sid; | |
1565 | rc = 0; | |
1566 | } else { | |
f5c1d5b2 | 1567 | rc = security_context_to_sid_default(context, rc, &sid, |
869ab514 SS |
1568 | sbsec->def_sid, |
1569 | GFP_NOFS); | |
1da177e4 | 1570 | if (rc) { |
4ba0a8ad EP |
1571 | char *dev = inode->i_sb->s_id; |
1572 | unsigned long ino = inode->i_ino; | |
1573 | ||
1574 | if (rc == -EINVAL) { | |
1575 | if (printk_ratelimit()) | |
1576 | printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " | |
1577 | "context=%s. This indicates you may need to relabel the inode or the " | |
1578 | "filesystem in question.\n", ino, dev, context); | |
1579 | } else { | |
1580 | printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " | |
1581 | "returned %d for dev=%s ino=%ld\n", | |
1582 | __func__, context, -rc, dev, ino); | |
1583 | } | |
1da177e4 LT |
1584 | kfree(context); |
1585 | /* Leave with the unlabeled SID */ | |
1586 | rc = 0; | |
1587 | break; | |
1588 | } | |
1589 | } | |
1590 | kfree(context); | |
1da177e4 LT |
1591 | break; |
1592 | case SECURITY_FS_USE_TASK: | |
9287aed2 | 1593 | sid = task_sid; |
1da177e4 LT |
1594 | break; |
1595 | case SECURITY_FS_USE_TRANS: | |
1596 | /* Default to the fs SID. */ | |
9287aed2 | 1597 | sid = sbsec->sid; |
1da177e4 LT |
1598 | |
1599 | /* Try to obtain a transition SID. */ | |
9287aed2 | 1600 | rc = security_transition_sid(task_sid, sid, sclass, NULL, &sid); |
1da177e4 | 1601 | if (rc) |
9287aed2 | 1602 | goto out; |
1da177e4 | 1603 | break; |
c312feb2 | 1604 | case SECURITY_FS_USE_MNTPOINT: |
9287aed2 | 1605 | sid = sbsec->mntpoint_sid; |
c312feb2 | 1606 | break; |
1da177e4 | 1607 | default: |
c312feb2 | 1608 | /* Default to the fs superblock SID. */ |
9287aed2 | 1609 | sid = sbsec->sid; |
1da177e4 | 1610 | |
134509d5 | 1611 | if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) { |
f64410ec PM |
1612 | /* We must have a dentry to determine the label on |
1613 | * procfs inodes */ | |
1614 | if (opt_dentry) | |
1615 | /* Called from d_instantiate or | |
1616 | * d_splice_alias. */ | |
1617 | dentry = dget(opt_dentry); | |
1618 | else | |
1619 | /* Called from selinux_complete_init, try to | |
1620 | * find a dentry. */ | |
1621 | dentry = d_find_alias(inode); | |
1622 | /* | |
1623 | * This can be hit on boot when a file is accessed | |
1624 | * before the policy is loaded. When we load policy we | |
1625 | * may find inodes that have no dentry on the | |
1626 | * sbsec->isec_head list. No reason to complain as | |
1627 | * these will get fixed up the next time we go through | |
1628 | * inode_doinit() with a dentry, before these inodes | |
1629 | * could be used again by userspace. | |
1630 | */ | |
1631 | if (!dentry) | |
9287aed2 AG |
1632 | goto out; |
1633 | rc = selinux_genfs_get_sid(dentry, sclass, | |
134509d5 | 1634 | sbsec->flags, &sid); |
f64410ec PM |
1635 | dput(dentry); |
1636 | if (rc) | |
9287aed2 | 1637 | goto out; |
1da177e4 LT |
1638 | } |
1639 | break; | |
1640 | } | |
1641 | ||
9287aed2 AG |
1642 | out: |
1643 | spin_lock(&isec->lock); | |
1644 | if (isec->initialized == LABEL_PENDING) { | |
1645 | if (!sid || rc) { | |
1646 | isec->initialized = LABEL_INVALID; | |
1647 | goto out_unlock; | |
1648 | } | |
1649 | ||
1650 | isec->initialized = LABEL_INITIALIZED; | |
1651 | isec->sid = sid; | |
1652 | } | |
1da177e4 | 1653 | |
23970741 | 1654 | out_unlock: |
9287aed2 | 1655 | spin_unlock(&isec->lock); |
1da177e4 LT |
1656 | return rc; |
1657 | } | |
1658 | ||
1659 | /* Convert a Linux signal to an access vector. */ | |
1660 | static inline u32 signal_to_av(int sig) | |
1661 | { | |
1662 | u32 perm = 0; | |
1663 | ||
1664 | switch (sig) { | |
1665 | case SIGCHLD: | |
1666 | /* Commonly granted from child to parent. */ | |
1667 | perm = PROCESS__SIGCHLD; | |
1668 | break; | |
1669 | case SIGKILL: | |
1670 | /* Cannot be caught or ignored */ | |
1671 | perm = PROCESS__SIGKILL; | |
1672 | break; | |
1673 | case SIGSTOP: | |
1674 | /* Cannot be caught or ignored */ | |
1675 | perm = PROCESS__SIGSTOP; | |
1676 | break; | |
1677 | default: | |
1678 | /* All other signals. */ | |
1679 | perm = PROCESS__SIGNAL; | |
1680 | break; | |
1681 | } | |
1682 | ||
1683 | return perm; | |
1684 | } | |
1685 | ||
d84f4f99 DH |
1686 | /* |
1687 | * Check permission between a pair of credentials | |
1688 | * fork check, ptrace check, etc. | |
1689 | */ | |
1690 | static int cred_has_perm(const struct cred *actor, | |
1691 | const struct cred *target, | |
1692 | u32 perms) | |
1693 | { | |
1694 | u32 asid = cred_sid(actor), tsid = cred_sid(target); | |
1695 | ||
1696 | return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); | |
1697 | } | |
1698 | ||
275bb41e | 1699 | /* |
88e67f3b | 1700 | * Check permission between a pair of tasks, e.g. signal checks, |
275bb41e DH |
1701 | * fork check, ptrace check, etc. |
1702 | * tsk1 is the actor and tsk2 is the target | |
3b11a1de | 1703 | * - this uses the default subjective creds of tsk1 |
275bb41e DH |
1704 | */ |
1705 | static int task_has_perm(const struct task_struct *tsk1, | |
1706 | const struct task_struct *tsk2, | |
1da177e4 LT |
1707 | u32 perms) |
1708 | { | |
275bb41e DH |
1709 | const struct task_security_struct *__tsec1, *__tsec2; |
1710 | u32 sid1, sid2; | |
1da177e4 | 1711 | |
275bb41e DH |
1712 | rcu_read_lock(); |
1713 | __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; | |
1714 | __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; | |
1715 | rcu_read_unlock(); | |
1716 | return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); | |
1da177e4 LT |
1717 | } |
1718 | ||
3b11a1de DH |
1719 | /* |
1720 | * Check permission between current and another task, e.g. signal checks, | |
1721 | * fork check, ptrace check, etc. | |
1722 | * current is the actor and tsk2 is the target | |
1723 | * - this uses current's subjective creds | |
1724 | */ | |
1725 | static int current_has_perm(const struct task_struct *tsk, | |
1726 | u32 perms) | |
1727 | { | |
1728 | u32 sid, tsid; | |
1729 | ||
1730 | sid = current_sid(); | |
1731 | tsid = task_sid(tsk); | |
1732 | return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); | |
1733 | } | |
1734 | ||
b68e418c SS |
1735 | #if CAP_LAST_CAP > 63 |
1736 | #error Fix SELinux to handle capabilities > 63. | |
1737 | #endif | |
1738 | ||
1da177e4 | 1739 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1740 | static int cred_has_capability(const struct cred *cred, |
8e4ff6f2 | 1741 | int cap, int audit, bool initns) |
1da177e4 | 1742 | { |
2bf49690 | 1743 | struct common_audit_data ad; |
06112163 | 1744 | struct av_decision avd; |
b68e418c | 1745 | u16 sclass; |
3699c53c | 1746 | u32 sid = cred_sid(cred); |
b68e418c | 1747 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1748 | int rc; |
1da177e4 | 1749 | |
50c205f5 | 1750 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1751 | ad.u.cap = cap; |
1752 | ||
b68e418c SS |
1753 | switch (CAP_TO_INDEX(cap)) { |
1754 | case 0: | |
8e4ff6f2 | 1755 | sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; |
b68e418c SS |
1756 | break; |
1757 | case 1: | |
8e4ff6f2 | 1758 | sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; |
b68e418c SS |
1759 | break; |
1760 | default: | |
1761 | printk(KERN_ERR | |
1762 | "SELinux: out of range capability %d\n", cap); | |
1763 | BUG(); | |
a35c6c83 | 1764 | return -EINVAL; |
b68e418c | 1765 | } |
06112163 | 1766 | |
275bb41e | 1767 | rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); |
9ade0cf4 | 1768 | if (audit == SECURITY_CAP_AUDIT) { |
7b20ea25 | 1769 | int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0); |
9ade0cf4 EP |
1770 | if (rc2) |
1771 | return rc2; | |
1772 | } | |
06112163 | 1773 | return rc; |
1da177e4 LT |
1774 | } |
1775 | ||
1776 | /* Check whether a task is allowed to use a system operation. */ | |
1777 | static int task_has_system(struct task_struct *tsk, | |
1778 | u32 perms) | |
1779 | { | |
275bb41e | 1780 | u32 sid = task_sid(tsk); |
1da177e4 | 1781 | |
275bb41e | 1782 | return avc_has_perm(sid, SECINITSID_KERNEL, |
1da177e4 LT |
1783 | SECCLASS_SYSTEM, perms, NULL); |
1784 | } | |
1785 | ||
1786 | /* Check whether a task has a particular permission to an inode. | |
1787 | The 'adp' parameter is optional and allows other audit | |
1788 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1789 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1790 | struct inode *inode, |
1791 | u32 perms, | |
19e49834 | 1792 | struct common_audit_data *adp) |
1da177e4 | 1793 | { |
1da177e4 | 1794 | struct inode_security_struct *isec; |
275bb41e | 1795 | u32 sid; |
1da177e4 | 1796 | |
e0e81739 DH |
1797 | validate_creds(cred); |
1798 | ||
828dfe1d | 1799 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1800 | return 0; |
1801 | ||
88e67f3b | 1802 | sid = cred_sid(cred); |
1da177e4 LT |
1803 | isec = inode->i_security; |
1804 | ||
19e49834 | 1805 | return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); |
1da177e4 LT |
1806 | } |
1807 | ||
1808 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1809 | the dentry to help the auditing code to more easily generate the | |
1810 | pathname if needed. */ | |
88e67f3b | 1811 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1812 | struct dentry *dentry, |
1813 | u32 av) | |
1814 | { | |
c6f493d6 | 1815 | struct inode *inode = d_backing_inode(dentry); |
2bf49690 | 1816 | struct common_audit_data ad; |
88e67f3b | 1817 | |
50c205f5 | 1818 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1819 | ad.u.dentry = dentry; |
5d226df4 | 1820 | __inode_security_revalidate(inode, dentry, true); |
19e49834 | 1821 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1822 | } |
1823 | ||
1824 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1825 | the path to help the auditing code to more easily generate the | |
1826 | pathname if needed. */ | |
1827 | static inline int path_has_perm(const struct cred *cred, | |
3f7036a0 | 1828 | const struct path *path, |
2875fa00 EP |
1829 | u32 av) |
1830 | { | |
c6f493d6 | 1831 | struct inode *inode = d_backing_inode(path->dentry); |
2875fa00 EP |
1832 | struct common_audit_data ad; |
1833 | ||
50c205f5 | 1834 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1835 | ad.u.path = *path; |
5d226df4 | 1836 | __inode_security_revalidate(inode, path->dentry, true); |
19e49834 | 1837 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1838 | } |
1839 | ||
13f8e981 DH |
1840 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1841 | static inline int file_path_has_perm(const struct cred *cred, | |
1842 | struct file *file, | |
1843 | u32 av) | |
1844 | { | |
1845 | struct common_audit_data ad; | |
1846 | ||
43af5de7 VG |
1847 | ad.type = LSM_AUDIT_DATA_FILE; |
1848 | ad.u.file = file; | |
19e49834 | 1849 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1850 | } |
1851 | ||
1da177e4 LT |
1852 | /* Check whether a task can use an open file descriptor to |
1853 | access an inode in a given way. Check access to the | |
1854 | descriptor itself, and then use dentry_has_perm to | |
1855 | check a particular permission to the file. | |
1856 | Access to the descriptor is implicitly granted if it | |
1857 | has the same SID as the process. If av is zero, then | |
1858 | access to the file is not checked, e.g. for cases | |
1859 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1860 | static int file_has_perm(const struct cred *cred, |
1861 | struct file *file, | |
1862 | u32 av) | |
1da177e4 | 1863 | { |
1da177e4 | 1864 | struct file_security_struct *fsec = file->f_security; |
496ad9aa | 1865 | struct inode *inode = file_inode(file); |
2bf49690 | 1866 | struct common_audit_data ad; |
88e67f3b | 1867 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1868 | int rc; |
1869 | ||
43af5de7 VG |
1870 | ad.type = LSM_AUDIT_DATA_FILE; |
1871 | ad.u.file = file; | |
1da177e4 | 1872 | |
275bb41e DH |
1873 | if (sid != fsec->sid) { |
1874 | rc = avc_has_perm(sid, fsec->sid, | |
1da177e4 LT |
1875 | SECCLASS_FD, |
1876 | FD__USE, | |
1877 | &ad); | |
1878 | if (rc) | |
88e67f3b | 1879 | goto out; |
1da177e4 LT |
1880 | } |
1881 | ||
1882 | /* av is zero if only checking access to the descriptor. */ | |
88e67f3b | 1883 | rc = 0; |
1da177e4 | 1884 | if (av) |
19e49834 | 1885 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1886 | |
88e67f3b DH |
1887 | out: |
1888 | return rc; | |
1da177e4 LT |
1889 | } |
1890 | ||
c3c188b2 DH |
1891 | /* |
1892 | * Determine the label for an inode that might be unioned. | |
1893 | */ | |
c957f6df VG |
1894 | static int |
1895 | selinux_determine_inode_label(const struct task_security_struct *tsec, | |
1896 | struct inode *dir, | |
1897 | const struct qstr *name, u16 tclass, | |
1898 | u32 *_new_isid) | |
c3c188b2 DH |
1899 | { |
1900 | const struct superblock_security_struct *sbsec = dir->i_sb->s_security; | |
c3c188b2 DH |
1901 | |
1902 | if ((sbsec->flags & SE_SBINITIALIZED) && | |
1903 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { | |
1904 | *_new_isid = sbsec->mntpoint_sid; | |
1905 | } else if ((sbsec->flags & SBLABEL_MNT) && | |
1906 | tsec->create_sid) { | |
1907 | *_new_isid = tsec->create_sid; | |
1908 | } else { | |
20cdef8d | 1909 | const struct inode_security_struct *dsec = inode_security(dir); |
c3c188b2 DH |
1910 | return security_transition_sid(tsec->sid, dsec->sid, tclass, |
1911 | name, _new_isid); | |
1912 | } | |
1913 | ||
1914 | return 0; | |
1915 | } | |
1916 | ||
1da177e4 LT |
1917 | /* Check whether a task can create a file. */ |
1918 | static int may_create(struct inode *dir, | |
1919 | struct dentry *dentry, | |
1920 | u16 tclass) | |
1921 | { | |
5fb49870 | 1922 | const struct task_security_struct *tsec = current_security(); |
1da177e4 LT |
1923 | struct inode_security_struct *dsec; |
1924 | struct superblock_security_struct *sbsec; | |
275bb41e | 1925 | u32 sid, newsid; |
2bf49690 | 1926 | struct common_audit_data ad; |
1da177e4 LT |
1927 | int rc; |
1928 | ||
83da53c5 | 1929 | dsec = inode_security(dir); |
1da177e4 LT |
1930 | sbsec = dir->i_sb->s_security; |
1931 | ||
275bb41e | 1932 | sid = tsec->sid; |
275bb41e | 1933 | |
50c205f5 | 1934 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1935 | ad.u.dentry = dentry; |
1da177e4 | 1936 | |
275bb41e | 1937 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
1938 | DIR__ADD_NAME | DIR__SEARCH, |
1939 | &ad); | |
1940 | if (rc) | |
1941 | return rc; | |
1942 | ||
c957f6df VG |
1943 | rc = selinux_determine_inode_label(current_security(), dir, |
1944 | &dentry->d_name, tclass, &newsid); | |
c3c188b2 DH |
1945 | if (rc) |
1946 | return rc; | |
1da177e4 | 1947 | |
275bb41e | 1948 | rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); |
1da177e4 LT |
1949 | if (rc) |
1950 | return rc; | |
1951 | ||
1952 | return avc_has_perm(newsid, sbsec->sid, | |
1953 | SECCLASS_FILESYSTEM, | |
1954 | FILESYSTEM__ASSOCIATE, &ad); | |
1955 | } | |
1956 | ||
4eb582cf ML |
1957 | /* Check whether a task can create a key. */ |
1958 | static int may_create_key(u32 ksid, | |
1959 | struct task_struct *ctx) | |
1960 | { | |
275bb41e | 1961 | u32 sid = task_sid(ctx); |
4eb582cf | 1962 | |
275bb41e | 1963 | return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); |
4eb582cf ML |
1964 | } |
1965 | ||
828dfe1d EP |
1966 | #define MAY_LINK 0 |
1967 | #define MAY_UNLINK 1 | |
1968 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1969 | |
1970 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1971 | static int may_link(struct inode *dir, | |
1972 | struct dentry *dentry, | |
1973 | int kind) | |
1974 | ||
1975 | { | |
1da177e4 | 1976 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 1977 | struct common_audit_data ad; |
275bb41e | 1978 | u32 sid = current_sid(); |
1da177e4 LT |
1979 | u32 av; |
1980 | int rc; | |
1981 | ||
83da53c5 AG |
1982 | dsec = inode_security(dir); |
1983 | isec = backing_inode_security(dentry); | |
1da177e4 | 1984 | |
50c205f5 | 1985 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1986 | ad.u.dentry = dentry; |
1da177e4 LT |
1987 | |
1988 | av = DIR__SEARCH; | |
1989 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
275bb41e | 1990 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
1991 | if (rc) |
1992 | return rc; | |
1993 | ||
1994 | switch (kind) { | |
1995 | case MAY_LINK: | |
1996 | av = FILE__LINK; | |
1997 | break; | |
1998 | case MAY_UNLINK: | |
1999 | av = FILE__UNLINK; | |
2000 | break; | |
2001 | case MAY_RMDIR: | |
2002 | av = DIR__RMDIR; | |
2003 | break; | |
2004 | default: | |
744ba35e EP |
2005 | printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", |
2006 | __func__, kind); | |
1da177e4 LT |
2007 | return 0; |
2008 | } | |
2009 | ||
275bb41e | 2010 | rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); |
1da177e4 LT |
2011 | return rc; |
2012 | } | |
2013 | ||
2014 | static inline int may_rename(struct inode *old_dir, | |
2015 | struct dentry *old_dentry, | |
2016 | struct inode *new_dir, | |
2017 | struct dentry *new_dentry) | |
2018 | { | |
1da177e4 | 2019 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 2020 | struct common_audit_data ad; |
275bb41e | 2021 | u32 sid = current_sid(); |
1da177e4 LT |
2022 | u32 av; |
2023 | int old_is_dir, new_is_dir; | |
2024 | int rc; | |
2025 | ||
83da53c5 AG |
2026 | old_dsec = inode_security(old_dir); |
2027 | old_isec = backing_inode_security(old_dentry); | |
e36cb0b8 | 2028 | old_is_dir = d_is_dir(old_dentry); |
83da53c5 | 2029 | new_dsec = inode_security(new_dir); |
1da177e4 | 2030 | |
50c205f5 | 2031 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 2032 | |
a269434d | 2033 | ad.u.dentry = old_dentry; |
275bb41e | 2034 | rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
2035 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
2036 | if (rc) | |
2037 | return rc; | |
275bb41e | 2038 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
2039 | old_isec->sclass, FILE__RENAME, &ad); |
2040 | if (rc) | |
2041 | return rc; | |
2042 | if (old_is_dir && new_dir != old_dir) { | |
275bb41e | 2043 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
2044 | old_isec->sclass, DIR__REPARENT, &ad); |
2045 | if (rc) | |
2046 | return rc; | |
2047 | } | |
2048 | ||
a269434d | 2049 | ad.u.dentry = new_dentry; |
1da177e4 | 2050 | av = DIR__ADD_NAME | DIR__SEARCH; |
2c616d4d | 2051 | if (d_is_positive(new_dentry)) |
1da177e4 | 2052 | av |= DIR__REMOVE_NAME; |
275bb41e | 2053 | rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
2054 | if (rc) |
2055 | return rc; | |
2c616d4d | 2056 | if (d_is_positive(new_dentry)) { |
83da53c5 | 2057 | new_isec = backing_inode_security(new_dentry); |
e36cb0b8 | 2058 | new_is_dir = d_is_dir(new_dentry); |
275bb41e | 2059 | rc = avc_has_perm(sid, new_isec->sid, |
1da177e4 LT |
2060 | new_isec->sclass, |
2061 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
2062 | if (rc) | |
2063 | return rc; | |
2064 | } | |
2065 | ||
2066 | return 0; | |
2067 | } | |
2068 | ||
2069 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 2070 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
2071 | struct super_block *sb, |
2072 | u32 perms, | |
2bf49690 | 2073 | struct common_audit_data *ad) |
1da177e4 | 2074 | { |
1da177e4 | 2075 | struct superblock_security_struct *sbsec; |
88e67f3b | 2076 | u32 sid = cred_sid(cred); |
1da177e4 | 2077 | |
1da177e4 | 2078 | sbsec = sb->s_security; |
275bb41e | 2079 | return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); |
1da177e4 LT |
2080 | } |
2081 | ||
2082 | /* Convert a Linux mode and permission mask to an access vector. */ | |
2083 | static inline u32 file_mask_to_av(int mode, int mask) | |
2084 | { | |
2085 | u32 av = 0; | |
2086 | ||
dba19c60 | 2087 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
2088 | if (mask & MAY_EXEC) |
2089 | av |= FILE__EXECUTE; | |
2090 | if (mask & MAY_READ) | |
2091 | av |= FILE__READ; | |
2092 | ||
2093 | if (mask & MAY_APPEND) | |
2094 | av |= FILE__APPEND; | |
2095 | else if (mask & MAY_WRITE) | |
2096 | av |= FILE__WRITE; | |
2097 | ||
2098 | } else { | |
2099 | if (mask & MAY_EXEC) | |
2100 | av |= DIR__SEARCH; | |
2101 | if (mask & MAY_WRITE) | |
2102 | av |= DIR__WRITE; | |
2103 | if (mask & MAY_READ) | |
2104 | av |= DIR__READ; | |
2105 | } | |
2106 | ||
2107 | return av; | |
2108 | } | |
2109 | ||
8b6a5a37 EP |
2110 | /* Convert a Linux file to an access vector. */ |
2111 | static inline u32 file_to_av(struct file *file) | |
2112 | { | |
2113 | u32 av = 0; | |
2114 | ||
2115 | if (file->f_mode & FMODE_READ) | |
2116 | av |= FILE__READ; | |
2117 | if (file->f_mode & FMODE_WRITE) { | |
2118 | if (file->f_flags & O_APPEND) | |
2119 | av |= FILE__APPEND; | |
2120 | else | |
2121 | av |= FILE__WRITE; | |
2122 | } | |
2123 | if (!av) { | |
2124 | /* | |
2125 | * Special file opened with flags 3 for ioctl-only use. | |
2126 | */ | |
2127 | av = FILE__IOCTL; | |
2128 | } | |
2129 | ||
2130 | return av; | |
2131 | } | |
2132 | ||
b0c636b9 | 2133 | /* |
8b6a5a37 | 2134 | * Convert a file to an access vector and include the correct open |
b0c636b9 EP |
2135 | * open permission. |
2136 | */ | |
8b6a5a37 | 2137 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 2138 | { |
8b6a5a37 | 2139 | u32 av = file_to_av(file); |
b0c636b9 | 2140 | |
49b7b8de EP |
2141 | if (selinux_policycap_openperm) |
2142 | av |= FILE__OPEN; | |
2143 | ||
b0c636b9 EP |
2144 | return av; |
2145 | } | |
2146 | ||
1da177e4 LT |
2147 | /* Hook functions begin here. */ |
2148 | ||
79af7307 SS |
2149 | static int selinux_binder_set_context_mgr(struct task_struct *mgr) |
2150 | { | |
2151 | u32 mysid = current_sid(); | |
2152 | u32 mgrsid = task_sid(mgr); | |
2153 | ||
2154 | return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER, | |
2155 | BINDER__SET_CONTEXT_MGR, NULL); | |
2156 | } | |
2157 | ||
2158 | static int selinux_binder_transaction(struct task_struct *from, | |
2159 | struct task_struct *to) | |
2160 | { | |
2161 | u32 mysid = current_sid(); | |
2162 | u32 fromsid = task_sid(from); | |
2163 | u32 tosid = task_sid(to); | |
2164 | int rc; | |
2165 | ||
2166 | if (mysid != fromsid) { | |
2167 | rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, | |
2168 | BINDER__IMPERSONATE, NULL); | |
2169 | if (rc) | |
2170 | return rc; | |
2171 | } | |
2172 | ||
2173 | return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, | |
2174 | NULL); | |
2175 | } | |
2176 | ||
2177 | static int selinux_binder_transfer_binder(struct task_struct *from, | |
2178 | struct task_struct *to) | |
2179 | { | |
2180 | u32 fromsid = task_sid(from); | |
2181 | u32 tosid = task_sid(to); | |
2182 | ||
2183 | return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, | |
2184 | NULL); | |
2185 | } | |
2186 | ||
2187 | static int selinux_binder_transfer_file(struct task_struct *from, | |
2188 | struct task_struct *to, | |
2189 | struct file *file) | |
2190 | { | |
2191 | u32 sid = task_sid(to); | |
2192 | struct file_security_struct *fsec = file->f_security; | |
83da53c5 | 2193 | struct dentry *dentry = file->f_path.dentry; |
20cdef8d | 2194 | struct inode_security_struct *isec; |
79af7307 SS |
2195 | struct common_audit_data ad; |
2196 | int rc; | |
2197 | ||
2198 | ad.type = LSM_AUDIT_DATA_PATH; | |
2199 | ad.u.path = file->f_path; | |
2200 | ||
2201 | if (sid != fsec->sid) { | |
2202 | rc = avc_has_perm(sid, fsec->sid, | |
2203 | SECCLASS_FD, | |
2204 | FD__USE, | |
2205 | &ad); | |
2206 | if (rc) | |
2207 | return rc; | |
2208 | } | |
2209 | ||
83da53c5 | 2210 | if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
79af7307 SS |
2211 | return 0; |
2212 | ||
20cdef8d | 2213 | isec = backing_inode_security(dentry); |
79af7307 SS |
2214 | return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), |
2215 | &ad); | |
2216 | } | |
2217 | ||
9e48858f | 2218 | static int selinux_ptrace_access_check(struct task_struct *child, |
5cd9c58f | 2219 | unsigned int mode) |
1da177e4 | 2220 | { |
69f594a3 | 2221 | if (mode & PTRACE_MODE_READ) { |
275bb41e DH |
2222 | u32 sid = current_sid(); |
2223 | u32 csid = task_sid(child); | |
2224 | return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 SS |
2225 | } |
2226 | ||
3b11a1de | 2227 | return current_has_perm(child, PROCESS__PTRACE); |
5cd9c58f DH |
2228 | } |
2229 | ||
2230 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
2231 | { | |
5cd9c58f | 2232 | return task_has_perm(parent, current, PROCESS__PTRACE); |
1da177e4 LT |
2233 | } |
2234 | ||
2235 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 2236 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 | 2237 | { |
b1d9e6b0 | 2238 | return current_has_perm(target, PROCESS__GETCAP); |
1da177e4 LT |
2239 | } |
2240 | ||
d84f4f99 DH |
2241 | static int selinux_capset(struct cred *new, const struct cred *old, |
2242 | const kernel_cap_t *effective, | |
2243 | const kernel_cap_t *inheritable, | |
2244 | const kernel_cap_t *permitted) | |
1da177e4 | 2245 | { |
d84f4f99 | 2246 | return cred_has_perm(old, new, PROCESS__SETCAP); |
1da177e4 LT |
2247 | } |
2248 | ||
5626d3e8 JM |
2249 | /* |
2250 | * (This comment used to live with the selinux_task_setuid hook, | |
2251 | * which was removed). | |
2252 | * | |
2253 | * Since setuid only affects the current process, and since the SELinux | |
2254 | * controls are not based on the Linux identity attributes, SELinux does not | |
2255 | * need to control this operation. However, SELinux does control the use of | |
2256 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
2257 | */ | |
2258 | ||
6a9de491 EP |
2259 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
2260 | int cap, int audit) | |
1da177e4 | 2261 | { |
8e4ff6f2 | 2262 | return cred_has_capability(cred, cap, audit, ns == &init_user_ns); |
1da177e4 LT |
2263 | } |
2264 | ||
1da177e4 LT |
2265 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
2266 | { | |
88e67f3b | 2267 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2268 | int rc = 0; |
2269 | ||
2270 | if (!sb) | |
2271 | return 0; | |
2272 | ||
2273 | switch (cmds) { | |
828dfe1d EP |
2274 | case Q_SYNC: |
2275 | case Q_QUOTAON: | |
2276 | case Q_QUOTAOFF: | |
2277 | case Q_SETINFO: | |
2278 | case Q_SETQUOTA: | |
88e67f3b | 2279 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
2280 | break; |
2281 | case Q_GETFMT: | |
2282 | case Q_GETINFO: | |
2283 | case Q_GETQUOTA: | |
88e67f3b | 2284 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
2285 | break; |
2286 | default: | |
2287 | rc = 0; /* let the kernel handle invalid cmds */ | |
2288 | break; | |
1da177e4 LT |
2289 | } |
2290 | return rc; | |
2291 | } | |
2292 | ||
2293 | static int selinux_quota_on(struct dentry *dentry) | |
2294 | { | |
88e67f3b DH |
2295 | const struct cred *cred = current_cred(); |
2296 | ||
2875fa00 | 2297 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
2298 | } |
2299 | ||
12b3052c | 2300 | static int selinux_syslog(int type) |
1da177e4 LT |
2301 | { |
2302 | int rc; | |
2303 | ||
1da177e4 | 2304 | switch (type) { |
d78ca3cd KC |
2305 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2306 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
828dfe1d EP |
2307 | rc = task_has_system(current, SYSTEM__SYSLOG_READ); |
2308 | break; | |
d78ca3cd KC |
2309 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2310 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2311 | /* Set level of messages printed to console */ | |
2312 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
828dfe1d EP |
2313 | rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); |
2314 | break; | |
d78ca3cd KC |
2315 | case SYSLOG_ACTION_CLOSE: /* Close log */ |
2316 | case SYSLOG_ACTION_OPEN: /* Open log */ | |
2317 | case SYSLOG_ACTION_READ: /* Read from log */ | |
2318 | case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ | |
2319 | case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ | |
828dfe1d EP |
2320 | default: |
2321 | rc = task_has_system(current, SYSTEM__SYSLOG_MOD); | |
2322 | break; | |
1da177e4 LT |
2323 | } |
2324 | return rc; | |
2325 | } | |
2326 | ||
2327 | /* | |
2328 | * Check that a process has enough memory to allocate a new virtual | |
2329 | * mapping. 0 means there is enough memory for the allocation to | |
2330 | * succeed and -ENOMEM implies there is not. | |
2331 | * | |
1da177e4 LT |
2332 | * Do not audit the selinux permission check, as this is applied to all |
2333 | * processes that allocate mappings. | |
2334 | */ | |
34b4e4aa | 2335 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2336 | { |
2337 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2338 | |
b1d9e6b0 | 2339 | rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, |
8e4ff6f2 | 2340 | SECURITY_CAP_NOAUDIT, true); |
1da177e4 LT |
2341 | if (rc == 0) |
2342 | cap_sys_admin = 1; | |
2343 | ||
b1d9e6b0 | 2344 | return cap_sys_admin; |
1da177e4 LT |
2345 | } |
2346 | ||
2347 | /* binprm security operations */ | |
2348 | ||
0c6181cb PM |
2349 | static u32 ptrace_parent_sid(struct task_struct *task) |
2350 | { | |
2351 | u32 sid = 0; | |
2352 | struct task_struct *tracer; | |
2353 | ||
2354 | rcu_read_lock(); | |
2355 | tracer = ptrace_parent(task); | |
2356 | if (tracer) | |
2357 | sid = task_sid(tracer); | |
2358 | rcu_read_unlock(); | |
2359 | ||
2360 | return sid; | |
2361 | } | |
2362 | ||
7b0d0b40 SS |
2363 | static int check_nnp_nosuid(const struct linux_binprm *bprm, |
2364 | const struct task_security_struct *old_tsec, | |
2365 | const struct task_security_struct *new_tsec) | |
2366 | { | |
2367 | int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); | |
380cf5ba | 2368 | int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); |
7b0d0b40 SS |
2369 | int rc; |
2370 | ||
2371 | if (!nnp && !nosuid) | |
2372 | return 0; /* neither NNP nor nosuid */ | |
2373 | ||
2374 | if (new_tsec->sid == old_tsec->sid) | |
2375 | return 0; /* No change in credentials */ | |
2376 | ||
2377 | /* | |
2378 | * The only transitions we permit under NNP or nosuid | |
2379 | * are transitions to bounded SIDs, i.e. SIDs that are | |
2380 | * guaranteed to only be allowed a subset of the permissions | |
2381 | * of the current SID. | |
2382 | */ | |
2383 | rc = security_bounded_transition(old_tsec->sid, new_tsec->sid); | |
2384 | if (rc) { | |
2385 | /* | |
2386 | * On failure, preserve the errno values for NNP vs nosuid. | |
2387 | * NNP: Operation not permitted for caller. | |
2388 | * nosuid: Permission denied to file. | |
2389 | */ | |
2390 | if (nnp) | |
2391 | return -EPERM; | |
2392 | else | |
2393 | return -EACCES; | |
2394 | } | |
2395 | return 0; | |
2396 | } | |
2397 | ||
a6f76f23 | 2398 | static int selinux_bprm_set_creds(struct linux_binprm *bprm) |
1da177e4 | 2399 | { |
a6f76f23 DH |
2400 | const struct task_security_struct *old_tsec; |
2401 | struct task_security_struct *new_tsec; | |
1da177e4 | 2402 | struct inode_security_struct *isec; |
2bf49690 | 2403 | struct common_audit_data ad; |
496ad9aa | 2404 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2405 | int rc; |
2406 | ||
a6f76f23 DH |
2407 | /* SELinux context only depends on initial program or script and not |
2408 | * the script interpreter */ | |
2409 | if (bprm->cred_prepared) | |
1da177e4 LT |
2410 | return 0; |
2411 | ||
a6f76f23 DH |
2412 | old_tsec = current_security(); |
2413 | new_tsec = bprm->cred->security; | |
83da53c5 | 2414 | isec = inode_security(inode); |
1da177e4 LT |
2415 | |
2416 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2417 | new_tsec->sid = old_tsec->sid; |
2418 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2419 | |
28eba5bf | 2420 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2421 | new_tsec->create_sid = 0; |
2422 | new_tsec->keycreate_sid = 0; | |
2423 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2424 | |
a6f76f23 DH |
2425 | if (old_tsec->exec_sid) { |
2426 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2427 | /* Reset exec SID on execve. */ |
a6f76f23 | 2428 | new_tsec->exec_sid = 0; |
259e5e6c | 2429 | |
7b0d0b40 SS |
2430 | /* Fail on NNP or nosuid if not an allowed transition. */ |
2431 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2432 | if (rc) | |
2433 | return rc; | |
1da177e4 LT |
2434 | } else { |
2435 | /* Check for a default transition on this program. */ | |
a6f76f23 | 2436 | rc = security_transition_sid(old_tsec->sid, isec->sid, |
652bb9b0 EP |
2437 | SECCLASS_PROCESS, NULL, |
2438 | &new_tsec->sid); | |
1da177e4 LT |
2439 | if (rc) |
2440 | return rc; | |
7b0d0b40 SS |
2441 | |
2442 | /* | |
2443 | * Fallback to old SID on NNP or nosuid if not an allowed | |
2444 | * transition. | |
2445 | */ | |
2446 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2447 | if (rc) | |
2448 | new_tsec->sid = old_tsec->sid; | |
1da177e4 LT |
2449 | } |
2450 | ||
43af5de7 VG |
2451 | ad.type = LSM_AUDIT_DATA_FILE; |
2452 | ad.u.file = bprm->file; | |
1da177e4 | 2453 | |
a6f76f23 DH |
2454 | if (new_tsec->sid == old_tsec->sid) { |
2455 | rc = avc_has_perm(old_tsec->sid, isec->sid, | |
1da177e4 LT |
2456 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2457 | if (rc) | |
2458 | return rc; | |
2459 | } else { | |
2460 | /* Check permissions for the transition. */ | |
a6f76f23 | 2461 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
1da177e4 LT |
2462 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2463 | if (rc) | |
2464 | return rc; | |
2465 | ||
a6f76f23 | 2466 | rc = avc_has_perm(new_tsec->sid, isec->sid, |
1da177e4 LT |
2467 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2468 | if (rc) | |
2469 | return rc; | |
2470 | ||
a6f76f23 DH |
2471 | /* Check for shared state */ |
2472 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
2473 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, | |
2474 | SECCLASS_PROCESS, PROCESS__SHARE, | |
2475 | NULL); | |
2476 | if (rc) | |
2477 | return -EPERM; | |
2478 | } | |
2479 | ||
2480 | /* Make sure that anyone attempting to ptrace over a task that | |
2481 | * changes its SID has the appropriate permit */ | |
2482 | if (bprm->unsafe & | |
2483 | (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { | |
0c6181cb | 2484 | u32 ptsid = ptrace_parent_sid(current); |
a6f76f23 DH |
2485 | if (ptsid != 0) { |
2486 | rc = avc_has_perm(ptsid, new_tsec->sid, | |
2487 | SECCLASS_PROCESS, | |
2488 | PROCESS__PTRACE, NULL); | |
2489 | if (rc) | |
2490 | return -EPERM; | |
2491 | } | |
2492 | } | |
1da177e4 | 2493 | |
a6f76f23 DH |
2494 | /* Clear any possibly unsafe personality bits on exec: */ |
2495 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
1da177e4 LT |
2496 | } |
2497 | ||
1da177e4 LT |
2498 | return 0; |
2499 | } | |
2500 | ||
828dfe1d | 2501 | static int selinux_bprm_secureexec(struct linux_binprm *bprm) |
1da177e4 | 2502 | { |
5fb49870 | 2503 | const struct task_security_struct *tsec = current_security(); |
275bb41e | 2504 | u32 sid, osid; |
1da177e4 LT |
2505 | int atsecure = 0; |
2506 | ||
275bb41e DH |
2507 | sid = tsec->sid; |
2508 | osid = tsec->osid; | |
2509 | ||
2510 | if (osid != sid) { | |
1da177e4 LT |
2511 | /* Enable secure mode for SIDs transitions unless |
2512 | the noatsecure permission is granted between | |
2513 | the two SIDs, i.e. ahp returns 0. */ | |
275bb41e | 2514 | atsecure = avc_has_perm(osid, sid, |
a6f76f23 DH |
2515 | SECCLASS_PROCESS, |
2516 | PROCESS__NOATSECURE, NULL); | |
1da177e4 LT |
2517 | } |
2518 | ||
b1d9e6b0 | 2519 | return !!atsecure; |
1da177e4 LT |
2520 | } |
2521 | ||
c3c073f8 AV |
2522 | static int match_file(const void *p, struct file *file, unsigned fd) |
2523 | { | |
2524 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2525 | } | |
2526 | ||
1da177e4 | 2527 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2528 | static inline void flush_unauthorized_files(const struct cred *cred, |
2529 | struct files_struct *files) | |
1da177e4 | 2530 | { |
1da177e4 | 2531 | struct file *file, *devnull = NULL; |
b20c8122 | 2532 | struct tty_struct *tty; |
24ec839c | 2533 | int drop_tty = 0; |
c3c073f8 | 2534 | unsigned n; |
1da177e4 | 2535 | |
24ec839c | 2536 | tty = get_current_tty(); |
1da177e4 | 2537 | if (tty) { |
4a510969 | 2538 | spin_lock(&tty->files_lock); |
37dd0bd0 | 2539 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2540 | struct tty_file_private *file_priv; |
37dd0bd0 | 2541 | |
1da177e4 | 2542 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2543 | Use file_path_has_perm on the tty path directly |
2544 | rather than using file_has_perm, as this particular | |
2545 | open file may belong to another process and we are | |
2546 | only interested in the inode-based check here. */ | |
d996b62a NP |
2547 | file_priv = list_first_entry(&tty->tty_files, |
2548 | struct tty_file_private, list); | |
2549 | file = file_priv->file; | |
13f8e981 | 2550 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2551 | drop_tty = 1; |
1da177e4 | 2552 | } |
4a510969 | 2553 | spin_unlock(&tty->files_lock); |
452a00d2 | 2554 | tty_kref_put(tty); |
1da177e4 | 2555 | } |
98a27ba4 EB |
2556 | /* Reset controlling tty. */ |
2557 | if (drop_tty) | |
2558 | no_tty(); | |
1da177e4 LT |
2559 | |
2560 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2561 | n = iterate_fd(files, 0, match_file, cred); |
2562 | if (!n) /* none found? */ | |
2563 | return; | |
1da177e4 | 2564 | |
c3c073f8 | 2565 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2566 | if (IS_ERR(devnull)) |
2567 | devnull = NULL; | |
2568 | /* replace all the matching ones with this */ | |
2569 | do { | |
2570 | replace_fd(n - 1, devnull, 0); | |
2571 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2572 | if (devnull) | |
c3c073f8 | 2573 | fput(devnull); |
1da177e4 LT |
2574 | } |
2575 | ||
a6f76f23 DH |
2576 | /* |
2577 | * Prepare a process for imminent new credential changes due to exec | |
2578 | */ | |
2579 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2580 | { |
a6f76f23 DH |
2581 | struct task_security_struct *new_tsec; |
2582 | struct rlimit *rlim, *initrlim; | |
2583 | int rc, i; | |
d84f4f99 | 2584 | |
a6f76f23 DH |
2585 | new_tsec = bprm->cred->security; |
2586 | if (new_tsec->sid == new_tsec->osid) | |
2587 | return; | |
1da177e4 | 2588 | |
a6f76f23 DH |
2589 | /* Close files for which the new task SID is not authorized. */ |
2590 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2591 | |
a6f76f23 DH |
2592 | /* Always clear parent death signal on SID transitions. */ |
2593 | current->pdeath_signal = 0; | |
0356357c | 2594 | |
a6f76f23 DH |
2595 | /* Check whether the new SID can inherit resource limits from the old |
2596 | * SID. If not, reset all soft limits to the lower of the current | |
2597 | * task's hard limit and the init task's soft limit. | |
2598 | * | |
2599 | * Note that the setting of hard limits (even to lower them) can be | |
2600 | * controlled by the setrlimit check. The inclusion of the init task's | |
2601 | * soft limit into the computation is to avoid resetting soft limits | |
2602 | * higher than the default soft limit for cases where the default is | |
2603 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2604 | */ | |
2605 | rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
2606 | PROCESS__RLIMITINH, NULL); | |
2607 | if (rc) { | |
eb2d55a3 ON |
2608 | /* protect against do_prlimit() */ |
2609 | task_lock(current); | |
a6f76f23 DH |
2610 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2611 | rlim = current->signal->rlim + i; | |
2612 | initrlim = init_task.signal->rlim + i; | |
2613 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2614 | } |
eb2d55a3 | 2615 | task_unlock(current); |
baa73d9e NP |
2616 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) |
2617 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2618 | } |
2619 | } | |
2620 | ||
2621 | /* | |
a6f76f23 DH |
2622 | * Clean up the process immediately after the installation of new credentials |
2623 | * due to exec | |
1da177e4 | 2624 | */ |
a6f76f23 | 2625 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2626 | { |
a6f76f23 | 2627 | const struct task_security_struct *tsec = current_security(); |
1da177e4 | 2628 | struct itimerval itimer; |
a6f76f23 | 2629 | u32 osid, sid; |
1da177e4 LT |
2630 | int rc, i; |
2631 | ||
a6f76f23 DH |
2632 | osid = tsec->osid; |
2633 | sid = tsec->sid; | |
2634 | ||
2635 | if (sid == osid) | |
1da177e4 LT |
2636 | return; |
2637 | ||
a6f76f23 DH |
2638 | /* Check whether the new SID can inherit signal state from the old SID. |
2639 | * If not, clear itimers to avoid subsequent signal generation and | |
2640 | * flush and unblock signals. | |
2641 | * | |
2642 | * This must occur _after_ the task SID has been updated so that any | |
2643 | * kill done after the flush will be checked against the new SID. | |
2644 | */ | |
2645 | rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 | 2646 | if (rc) { |
baa73d9e NP |
2647 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) { |
2648 | memset(&itimer, 0, sizeof itimer); | |
2649 | for (i = 0; i < 3; i++) | |
2650 | do_setitimer(i, &itimer, NULL); | |
2651 | } | |
1da177e4 | 2652 | spin_lock_irq(¤t->sighand->siglock); |
9e7c8f8c ON |
2653 | if (!fatal_signal_pending(current)) { |
2654 | flush_sigqueue(¤t->pending); | |
2655 | flush_sigqueue(¤t->signal->shared_pending); | |
3bcac026 DH |
2656 | flush_signal_handlers(current, 1); |
2657 | sigemptyset(¤t->blocked); | |
9e7c8f8c | 2658 | recalc_sigpending(); |
3bcac026 | 2659 | } |
1da177e4 LT |
2660 | spin_unlock_irq(¤t->sighand->siglock); |
2661 | } | |
2662 | ||
a6f76f23 DH |
2663 | /* Wake up the parent if it is waiting so that it can recheck |
2664 | * wait permission to the new task SID. */ | |
ecd6de3c | 2665 | read_lock(&tasklist_lock); |
0b7570e7 | 2666 | __wake_up_parent(current, current->real_parent); |
ecd6de3c | 2667 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2668 | } |
2669 | ||
2670 | /* superblock security operations */ | |
2671 | ||
2672 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2673 | { | |
2674 | return superblock_alloc_security(sb); | |
2675 | } | |
2676 | ||
2677 | static void selinux_sb_free_security(struct super_block *sb) | |
2678 | { | |
2679 | superblock_free_security(sb); | |
2680 | } | |
2681 | ||
2682 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2683 | { | |
2684 | if (plen > olen) | |
2685 | return 0; | |
2686 | ||
2687 | return !memcmp(prefix, option, plen); | |
2688 | } | |
2689 | ||
2690 | static inline int selinux_option(char *option, int len) | |
2691 | { | |
832cbd9a EP |
2692 | return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || |
2693 | match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || | |
2694 | match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || | |
11689d47 DQ |
2695 | match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || |
2696 | match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); | |
1da177e4 LT |
2697 | } |
2698 | ||
2699 | static inline void take_option(char **to, char *from, int *first, int len) | |
2700 | { | |
2701 | if (!*first) { | |
2702 | **to = ','; | |
2703 | *to += 1; | |
3528a953 | 2704 | } else |
1da177e4 LT |
2705 | *first = 0; |
2706 | memcpy(*to, from, len); | |
2707 | *to += len; | |
2708 | } | |
2709 | ||
828dfe1d EP |
2710 | static inline void take_selinux_option(char **to, char *from, int *first, |
2711 | int len) | |
3528a953 CO |
2712 | { |
2713 | int current_size = 0; | |
2714 | ||
2715 | if (!*first) { | |
2716 | **to = '|'; | |
2717 | *to += 1; | |
828dfe1d | 2718 | } else |
3528a953 CO |
2719 | *first = 0; |
2720 | ||
2721 | while (current_size < len) { | |
2722 | if (*from != '"') { | |
2723 | **to = *from; | |
2724 | *to += 1; | |
2725 | } | |
2726 | from += 1; | |
2727 | current_size += 1; | |
2728 | } | |
2729 | } | |
2730 | ||
e0007529 | 2731 | static int selinux_sb_copy_data(char *orig, char *copy) |
1da177e4 LT |
2732 | { |
2733 | int fnosec, fsec, rc = 0; | |
2734 | char *in_save, *in_curr, *in_end; | |
2735 | char *sec_curr, *nosec_save, *nosec; | |
3528a953 | 2736 | int open_quote = 0; |
1da177e4 LT |
2737 | |
2738 | in_curr = orig; | |
2739 | sec_curr = copy; | |
2740 | ||
1da177e4 LT |
2741 | nosec = (char *)get_zeroed_page(GFP_KERNEL); |
2742 | if (!nosec) { | |
2743 | rc = -ENOMEM; | |
2744 | goto out; | |
2745 | } | |
2746 | ||
2747 | nosec_save = nosec; | |
2748 | fnosec = fsec = 1; | |
2749 | in_save = in_end = orig; | |
2750 | ||
2751 | do { | |
3528a953 CO |
2752 | if (*in_end == '"') |
2753 | open_quote = !open_quote; | |
2754 | if ((*in_end == ',' && open_quote == 0) || | |
2755 | *in_end == '\0') { | |
1da177e4 LT |
2756 | int len = in_end - in_curr; |
2757 | ||
2758 | if (selinux_option(in_curr, len)) | |
3528a953 | 2759 | take_selinux_option(&sec_curr, in_curr, &fsec, len); |
1da177e4 LT |
2760 | else |
2761 | take_option(&nosec, in_curr, &fnosec, len); | |
2762 | ||
2763 | in_curr = in_end + 1; | |
2764 | } | |
2765 | } while (*in_end++); | |
2766 | ||
6931dfc9 | 2767 | strcpy(in_save, nosec_save); |
da3caa20 | 2768 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
2769 | out: |
2770 | return rc; | |
2771 | } | |
2772 | ||
026eb167 EP |
2773 | static int selinux_sb_remount(struct super_block *sb, void *data) |
2774 | { | |
2775 | int rc, i, *flags; | |
2776 | struct security_mnt_opts opts; | |
2777 | char *secdata, **mount_options; | |
2778 | struct superblock_security_struct *sbsec = sb->s_security; | |
2779 | ||
2780 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2781 | return 0; | |
2782 | ||
2783 | if (!data) | |
2784 | return 0; | |
2785 | ||
2786 | if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) | |
2787 | return 0; | |
2788 | ||
2789 | security_init_mnt_opts(&opts); | |
2790 | secdata = alloc_secdata(); | |
2791 | if (!secdata) | |
2792 | return -ENOMEM; | |
2793 | rc = selinux_sb_copy_data(data, secdata); | |
2794 | if (rc) | |
2795 | goto out_free_secdata; | |
2796 | ||
2797 | rc = selinux_parse_opts_str(secdata, &opts); | |
2798 | if (rc) | |
2799 | goto out_free_secdata; | |
2800 | ||
2801 | mount_options = opts.mnt_opts; | |
2802 | flags = opts.mnt_opts_flags; | |
2803 | ||
2804 | for (i = 0; i < opts.num_mnt_opts; i++) { | |
2805 | u32 sid; | |
026eb167 | 2806 | |
12f348b9 | 2807 | if (flags[i] == SBLABEL_MNT) |
026eb167 | 2808 | continue; |
44be2f65 | 2809 | rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL); |
026eb167 | 2810 | if (rc) { |
44be2f65 | 2811 | printk(KERN_WARNING "SELinux: security_context_str_to_sid" |
29b1deb2 LT |
2812 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
2813 | mount_options[i], sb->s_id, sb->s_type->name, rc); | |
026eb167 EP |
2814 | goto out_free_opts; |
2815 | } | |
2816 | rc = -EINVAL; | |
2817 | switch (flags[i]) { | |
2818 | case FSCONTEXT_MNT: | |
2819 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) | |
2820 | goto out_bad_option; | |
2821 | break; | |
2822 | case CONTEXT_MNT: | |
2823 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2824 | goto out_bad_option; | |
2825 | break; | |
2826 | case ROOTCONTEXT_MNT: { | |
2827 | struct inode_security_struct *root_isec; | |
83da53c5 | 2828 | root_isec = backing_inode_security(sb->s_root); |
026eb167 EP |
2829 | |
2830 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2831 | goto out_bad_option; | |
2832 | break; | |
2833 | } | |
2834 | case DEFCONTEXT_MNT: | |
2835 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2836 | goto out_bad_option; | |
2837 | break; | |
2838 | default: | |
2839 | goto out_free_opts; | |
2840 | } | |
2841 | } | |
2842 | ||
2843 | rc = 0; | |
2844 | out_free_opts: | |
2845 | security_free_mnt_opts(&opts); | |
2846 | out_free_secdata: | |
2847 | free_secdata(secdata); | |
2848 | return rc; | |
2849 | out_bad_option: | |
2850 | printk(KERN_WARNING "SELinux: unable to change security options " | |
29b1deb2 LT |
2851 | "during remount (dev %s, type=%s)\n", sb->s_id, |
2852 | sb->s_type->name); | |
026eb167 EP |
2853 | goto out_free_opts; |
2854 | } | |
2855 | ||
12204e24 | 2856 | static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) |
1da177e4 | 2857 | { |
88e67f3b | 2858 | const struct cred *cred = current_cred(); |
2bf49690 | 2859 | struct common_audit_data ad; |
1da177e4 LT |
2860 | int rc; |
2861 | ||
2862 | rc = superblock_doinit(sb, data); | |
2863 | if (rc) | |
2864 | return rc; | |
2865 | ||
74192246 JM |
2866 | /* Allow all mounts performed by the kernel */ |
2867 | if (flags & MS_KERNMOUNT) | |
2868 | return 0; | |
2869 | ||
50c205f5 | 2870 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2871 | ad.u.dentry = sb->s_root; |
88e67f3b | 2872 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2873 | } |
2874 | ||
726c3342 | 2875 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2876 | { |
88e67f3b | 2877 | const struct cred *cred = current_cred(); |
2bf49690 | 2878 | struct common_audit_data ad; |
1da177e4 | 2879 | |
50c205f5 | 2880 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2881 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2882 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2883 | } |
2884 | ||
808d4e3c | 2885 | static int selinux_mount(const char *dev_name, |
8a04c43b | 2886 | const struct path *path, |
808d4e3c | 2887 | const char *type, |
828dfe1d EP |
2888 | unsigned long flags, |
2889 | void *data) | |
1da177e4 | 2890 | { |
88e67f3b | 2891 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2892 | |
2893 | if (flags & MS_REMOUNT) | |
d8c9584e | 2894 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2895 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2896 | else |
2875fa00 | 2897 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2898 | } |
2899 | ||
2900 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2901 | { | |
88e67f3b | 2902 | const struct cred *cred = current_cred(); |
1da177e4 | 2903 | |
88e67f3b | 2904 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2905 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2906 | } |
2907 | ||
2908 | /* inode security operations */ | |
2909 | ||
2910 | static int selinux_inode_alloc_security(struct inode *inode) | |
2911 | { | |
2912 | return inode_alloc_security(inode); | |
2913 | } | |
2914 | ||
2915 | static void selinux_inode_free_security(struct inode *inode) | |
2916 | { | |
2917 | inode_free_security(inode); | |
2918 | } | |
2919 | ||
d47be3df | 2920 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
4f3ccd76 | 2921 | const struct qstr *name, void **ctx, |
d47be3df DQ |
2922 | u32 *ctxlen) |
2923 | { | |
d47be3df DQ |
2924 | u32 newsid; |
2925 | int rc; | |
2926 | ||
c957f6df VG |
2927 | rc = selinux_determine_inode_label(current_security(), |
2928 | d_inode(dentry->d_parent), name, | |
c3c188b2 DH |
2929 | inode_mode_to_security_class(mode), |
2930 | &newsid); | |
2931 | if (rc) | |
2932 | return rc; | |
d47be3df DQ |
2933 | |
2934 | return security_sid_to_context(newsid, (char **)ctx, ctxlen); | |
2935 | } | |
2936 | ||
a518b0a5 VG |
2937 | static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, |
2938 | struct qstr *name, | |
2939 | const struct cred *old, | |
2940 | struct cred *new) | |
2941 | { | |
2942 | u32 newsid; | |
2943 | int rc; | |
2944 | struct task_security_struct *tsec; | |
2945 | ||
2946 | rc = selinux_determine_inode_label(old->security, | |
2947 | d_inode(dentry->d_parent), name, | |
2948 | inode_mode_to_security_class(mode), | |
2949 | &newsid); | |
2950 | if (rc) | |
2951 | return rc; | |
2952 | ||
2953 | tsec = new->security; | |
2954 | tsec->create_sid = newsid; | |
2955 | return 0; | |
2956 | } | |
2957 | ||
5e41ff9e | 2958 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
2959 | const struct qstr *qstr, |
2960 | const char **name, | |
2a7dba39 | 2961 | void **value, size_t *len) |
5e41ff9e | 2962 | { |
5fb49870 | 2963 | const struct task_security_struct *tsec = current_security(); |
5e41ff9e | 2964 | struct superblock_security_struct *sbsec; |
275bb41e | 2965 | u32 sid, newsid, clen; |
5e41ff9e | 2966 | int rc; |
9548906b | 2967 | char *context; |
5e41ff9e | 2968 | |
5e41ff9e | 2969 | sbsec = dir->i_sb->s_security; |
5e41ff9e | 2970 | |
275bb41e DH |
2971 | sid = tsec->sid; |
2972 | newsid = tsec->create_sid; | |
2973 | ||
c957f6df | 2974 | rc = selinux_determine_inode_label(current_security(), |
c3c188b2 DH |
2975 | dir, qstr, |
2976 | inode_mode_to_security_class(inode->i_mode), | |
2977 | &newsid); | |
2978 | if (rc) | |
2979 | return rc; | |
5e41ff9e | 2980 | |
296fddf7 | 2981 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 2982 | if (sbsec->flags & SE_SBINITIALIZED) { |
296fddf7 EP |
2983 | struct inode_security_struct *isec = inode->i_security; |
2984 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
2985 | isec->sid = newsid; | |
6f3be9f5 | 2986 | isec->initialized = LABEL_INITIALIZED; |
296fddf7 | 2987 | } |
5e41ff9e | 2988 | |
12f348b9 | 2989 | if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT)) |
25a74f3b SS |
2990 | return -EOPNOTSUPP; |
2991 | ||
9548906b TH |
2992 | if (name) |
2993 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 2994 | |
570bc1c2 | 2995 | if (value && len) { |
12b29f34 | 2996 | rc = security_sid_to_context_force(newsid, &context, &clen); |
9548906b | 2997 | if (rc) |
570bc1c2 | 2998 | return rc; |
570bc1c2 SS |
2999 | *value = context; |
3000 | *len = clen; | |
5e41ff9e | 3001 | } |
5e41ff9e | 3002 | |
5e41ff9e SS |
3003 | return 0; |
3004 | } | |
3005 | ||
4acdaf27 | 3006 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
3007 | { |
3008 | return may_create(dir, dentry, SECCLASS_FILE); | |
3009 | } | |
3010 | ||
1da177e4 LT |
3011 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
3012 | { | |
1da177e4 LT |
3013 | return may_link(dir, old_dentry, MAY_LINK); |
3014 | } | |
3015 | ||
1da177e4 LT |
3016 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
3017 | { | |
1da177e4 LT |
3018 | return may_link(dir, dentry, MAY_UNLINK); |
3019 | } | |
3020 | ||
3021 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
3022 | { | |
3023 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
3024 | } | |
3025 | ||
18bb1db3 | 3026 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
3027 | { |
3028 | return may_create(dir, dentry, SECCLASS_DIR); | |
3029 | } | |
3030 | ||
1da177e4 LT |
3031 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
3032 | { | |
3033 | return may_link(dir, dentry, MAY_RMDIR); | |
3034 | } | |
3035 | ||
1a67aafb | 3036 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 3037 | { |
1da177e4 LT |
3038 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
3039 | } | |
3040 | ||
1da177e4 | 3041 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 3042 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
3043 | { |
3044 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
3045 | } | |
3046 | ||
1da177e4 LT |
3047 | static int selinux_inode_readlink(struct dentry *dentry) |
3048 | { | |
88e67f3b DH |
3049 | const struct cred *cred = current_cred(); |
3050 | ||
2875fa00 | 3051 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
3052 | } |
3053 | ||
bda0be7a N |
3054 | static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, |
3055 | bool rcu) | |
1da177e4 | 3056 | { |
88e67f3b | 3057 | const struct cred *cred = current_cred(); |
bda0be7a N |
3058 | struct common_audit_data ad; |
3059 | struct inode_security_struct *isec; | |
3060 | u32 sid; | |
1da177e4 | 3061 | |
bda0be7a N |
3062 | validate_creds(cred); |
3063 | ||
3064 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
3065 | ad.u.dentry = dentry; | |
3066 | sid = cred_sid(cred); | |
5d226df4 AG |
3067 | isec = inode_security_rcu(inode, rcu); |
3068 | if (IS_ERR(isec)) | |
3069 | return PTR_ERR(isec); | |
bda0be7a N |
3070 | |
3071 | return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad, | |
3072 | rcu ? MAY_NOT_BLOCK : 0); | |
1da177e4 LT |
3073 | } |
3074 | ||
d4cf970d EP |
3075 | static noinline int audit_inode_permission(struct inode *inode, |
3076 | u32 perms, u32 audited, u32 denied, | |
626b9740 | 3077 | int result, |
d4cf970d | 3078 | unsigned flags) |
1da177e4 | 3079 | { |
b782e0a6 | 3080 | struct common_audit_data ad; |
d4cf970d EP |
3081 | struct inode_security_struct *isec = inode->i_security; |
3082 | int rc; | |
3083 | ||
50c205f5 | 3084 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
3085 | ad.u.inode = inode; |
3086 | ||
3087 | rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, | |
626b9740 | 3088 | audited, denied, result, &ad, flags); |
d4cf970d EP |
3089 | if (rc) |
3090 | return rc; | |
3091 | return 0; | |
3092 | } | |
3093 | ||
e74f71eb | 3094 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 3095 | { |
88e67f3b | 3096 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
3097 | u32 perms; |
3098 | bool from_access; | |
cf1dd1da | 3099 | unsigned flags = mask & MAY_NOT_BLOCK; |
2e334057 EP |
3100 | struct inode_security_struct *isec; |
3101 | u32 sid; | |
3102 | struct av_decision avd; | |
3103 | int rc, rc2; | |
3104 | u32 audited, denied; | |
1da177e4 | 3105 | |
b782e0a6 | 3106 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
3107 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
3108 | ||
b782e0a6 EP |
3109 | /* No permission to check. Existence test. */ |
3110 | if (!mask) | |
1da177e4 | 3111 | return 0; |
1da177e4 | 3112 | |
2e334057 | 3113 | validate_creds(cred); |
b782e0a6 | 3114 | |
2e334057 EP |
3115 | if (unlikely(IS_PRIVATE(inode))) |
3116 | return 0; | |
b782e0a6 EP |
3117 | |
3118 | perms = file_mask_to_av(inode->i_mode, mask); | |
3119 | ||
2e334057 | 3120 | sid = cred_sid(cred); |
5d226df4 AG |
3121 | isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK); |
3122 | if (IS_ERR(isec)) | |
3123 | return PTR_ERR(isec); | |
2e334057 EP |
3124 | |
3125 | rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd); | |
3126 | audited = avc_audit_required(perms, &avd, rc, | |
3127 | from_access ? FILE__AUDIT_ACCESS : 0, | |
3128 | &denied); | |
3129 | if (likely(!audited)) | |
3130 | return rc; | |
3131 | ||
626b9740 | 3132 | rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags); |
2e334057 EP |
3133 | if (rc2) |
3134 | return rc2; | |
3135 | return rc; | |
1da177e4 LT |
3136 | } |
3137 | ||
3138 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
3139 | { | |
88e67f3b | 3140 | const struct cred *cred = current_cred(); |
bc6a6008 | 3141 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 3142 | __u32 av = FILE__WRITE; |
1da177e4 | 3143 | |
bc6a6008 AW |
3144 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
3145 | if (ia_valid & ATTR_FORCE) { | |
3146 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
3147 | ATTR_FORCE); | |
3148 | if (!ia_valid) | |
3149 | return 0; | |
3150 | } | |
1da177e4 | 3151 | |
bc6a6008 AW |
3152 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
3153 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 3154 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 3155 | |
44d37ad3 JVS |
3156 | if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE) |
3157 | && !(ia_valid & ATTR_FILE)) | |
95dbf739 EP |
3158 | av |= FILE__OPEN; |
3159 | ||
3160 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
3161 | } |
3162 | ||
3f7036a0 | 3163 | static int selinux_inode_getattr(const struct path *path) |
1da177e4 | 3164 | { |
3f7036a0 | 3165 | return path_has_perm(current_cred(), path, FILE__GETATTR); |
1da177e4 LT |
3166 | } |
3167 | ||
8f0cfa52 | 3168 | static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) |
b5376771 | 3169 | { |
88e67f3b DH |
3170 | const struct cred *cred = current_cred(); |
3171 | ||
b5376771 SH |
3172 | if (!strncmp(name, XATTR_SECURITY_PREFIX, |
3173 | sizeof XATTR_SECURITY_PREFIX - 1)) { | |
3174 | if (!strcmp(name, XATTR_NAME_CAPS)) { | |
3175 | if (!capable(CAP_SETFCAP)) | |
3176 | return -EPERM; | |
3177 | } else if (!capable(CAP_SYS_ADMIN)) { | |
3178 | /* A different attribute in the security namespace. | |
3179 | Restrict to administrator. */ | |
3180 | return -EPERM; | |
3181 | } | |
3182 | } | |
3183 | ||
3184 | /* Not an attribute we recognize, so just check the | |
3185 | ordinary setattr permission. */ | |
2875fa00 | 3186 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
b5376771 SH |
3187 | } |
3188 | ||
8f0cfa52 DH |
3189 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
3190 | const void *value, size_t size, int flags) | |
1da177e4 | 3191 | { |
c6f493d6 | 3192 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3193 | struct inode_security_struct *isec; |
1da177e4 | 3194 | struct superblock_security_struct *sbsec; |
2bf49690 | 3195 | struct common_audit_data ad; |
275bb41e | 3196 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
3197 | int rc = 0; |
3198 | ||
b5376771 SH |
3199 | if (strcmp(name, XATTR_NAME_SELINUX)) |
3200 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
3201 | |
3202 | sbsec = inode->i_sb->s_security; | |
12f348b9 | 3203 | if (!(sbsec->flags & SBLABEL_MNT)) |
1da177e4 LT |
3204 | return -EOPNOTSUPP; |
3205 | ||
2e149670 | 3206 | if (!inode_owner_or_capable(inode)) |
1da177e4 LT |
3207 | return -EPERM; |
3208 | ||
50c205f5 | 3209 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 3210 | ad.u.dentry = dentry; |
1da177e4 | 3211 | |
20cdef8d | 3212 | isec = backing_inode_security(dentry); |
275bb41e | 3213 | rc = avc_has_perm(sid, isec->sid, isec->sclass, |
1da177e4 LT |
3214 | FILE__RELABELFROM, &ad); |
3215 | if (rc) | |
3216 | return rc; | |
3217 | ||
52a4c640 | 3218 | rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); |
12b29f34 | 3219 | if (rc == -EINVAL) { |
d6ea83ec EP |
3220 | if (!capable(CAP_MAC_ADMIN)) { |
3221 | struct audit_buffer *ab; | |
3222 | size_t audit_size; | |
3223 | const char *str; | |
3224 | ||
3225 | /* We strip a nul only if it is at the end, otherwise the | |
3226 | * context contains a nul and we should audit that */ | |
e3fea3f7 AV |
3227 | if (value) { |
3228 | str = value; | |
3229 | if (str[size - 1] == '\0') | |
3230 | audit_size = size - 1; | |
3231 | else | |
3232 | audit_size = size; | |
3233 | } else { | |
3234 | str = ""; | |
3235 | audit_size = 0; | |
3236 | } | |
d6ea83ec EP |
3237 | ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); |
3238 | audit_log_format(ab, "op=setxattr invalid_context="); | |
3239 | audit_log_n_untrustedstring(ab, value, audit_size); | |
3240 | audit_log_end(ab); | |
3241 | ||
12b29f34 | 3242 | return rc; |
d6ea83ec | 3243 | } |
12b29f34 SS |
3244 | rc = security_context_to_sid_force(value, size, &newsid); |
3245 | } | |
1da177e4 LT |
3246 | if (rc) |
3247 | return rc; | |
3248 | ||
275bb41e | 3249 | rc = avc_has_perm(sid, newsid, isec->sclass, |
1da177e4 LT |
3250 | FILE__RELABELTO, &ad); |
3251 | if (rc) | |
3252 | return rc; | |
3253 | ||
275bb41e | 3254 | rc = security_validate_transition(isec->sid, newsid, sid, |
828dfe1d | 3255 | isec->sclass); |
1da177e4 LT |
3256 | if (rc) |
3257 | return rc; | |
3258 | ||
3259 | return avc_has_perm(newsid, | |
3260 | sbsec->sid, | |
3261 | SECCLASS_FILESYSTEM, | |
3262 | FILESYSTEM__ASSOCIATE, | |
3263 | &ad); | |
3264 | } | |
3265 | ||
8f0cfa52 | 3266 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 3267 | const void *value, size_t size, |
8f0cfa52 | 3268 | int flags) |
1da177e4 | 3269 | { |
c6f493d6 | 3270 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3271 | struct inode_security_struct *isec; |
1da177e4 LT |
3272 | u32 newsid; |
3273 | int rc; | |
3274 | ||
3275 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
3276 | /* Not an attribute we recognize, so nothing to do. */ | |
3277 | return; | |
3278 | } | |
3279 | ||
12b29f34 | 3280 | rc = security_context_to_sid_force(value, size, &newsid); |
1da177e4 | 3281 | if (rc) { |
12b29f34 SS |
3282 | printk(KERN_ERR "SELinux: unable to map context to SID" |
3283 | "for (%s, %lu), rc=%d\n", | |
3284 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
3285 | return; |
3286 | } | |
3287 | ||
20cdef8d | 3288 | isec = backing_inode_security(dentry); |
9287aed2 | 3289 | spin_lock(&isec->lock); |
aa9c2669 | 3290 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3291 | isec->sid = newsid; |
6f3be9f5 | 3292 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3293 | spin_unlock(&isec->lock); |
aa9c2669 | 3294 | |
1da177e4 LT |
3295 | return; |
3296 | } | |
3297 | ||
8f0cfa52 | 3298 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 3299 | { |
88e67f3b DH |
3300 | const struct cred *cred = current_cred(); |
3301 | ||
2875fa00 | 3302 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3303 | } |
3304 | ||
828dfe1d | 3305 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 3306 | { |
88e67f3b DH |
3307 | const struct cred *cred = current_cred(); |
3308 | ||
2875fa00 | 3309 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3310 | } |
3311 | ||
8f0cfa52 | 3312 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 3313 | { |
b5376771 SH |
3314 | if (strcmp(name, XATTR_NAME_SELINUX)) |
3315 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
3316 | |
3317 | /* No one is allowed to remove a SELinux security label. | |
3318 | You can change the label, but all data must be labeled. */ | |
3319 | return -EACCES; | |
3320 | } | |
3321 | ||
d381d8a9 | 3322 | /* |
abc69bb6 | 3323 | * Copy the inode security context value to the user. |
d381d8a9 JM |
3324 | * |
3325 | * Permission check is handled by selinux_inode_getxattr hook. | |
3326 | */ | |
ea861dfd | 3327 | static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 3328 | { |
42492594 DQ |
3329 | u32 size; |
3330 | int error; | |
3331 | char *context = NULL; | |
20cdef8d | 3332 | struct inode_security_struct *isec; |
d381d8a9 | 3333 | |
8c8570fb DK |
3334 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
3335 | return -EOPNOTSUPP; | |
d381d8a9 | 3336 | |
abc69bb6 SS |
3337 | /* |
3338 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3339 | * value even if it is not defined by current policy; otherwise, | |
3340 | * use the in-core value under current policy. | |
3341 | * Use the non-auditing forms of the permission checks since | |
3342 | * getxattr may be called by unprivileged processes commonly | |
3343 | * and lack of permission just means that we fall back to the | |
3344 | * in-core context value, not a denial. | |
3345 | */ | |
b1d9e6b0 CS |
3346 | error = cap_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN, |
3347 | SECURITY_CAP_NOAUDIT); | |
3348 | if (!error) | |
3349 | error = cred_has_capability(current_cred(), CAP_MAC_ADMIN, | |
8e4ff6f2 | 3350 | SECURITY_CAP_NOAUDIT, true); |
20cdef8d | 3351 | isec = inode_security(inode); |
abc69bb6 SS |
3352 | if (!error) |
3353 | error = security_sid_to_context_force(isec->sid, &context, | |
3354 | &size); | |
3355 | else | |
3356 | error = security_sid_to_context(isec->sid, &context, &size); | |
42492594 DQ |
3357 | if (error) |
3358 | return error; | |
3359 | error = size; | |
3360 | if (alloc) { | |
3361 | *buffer = context; | |
3362 | goto out_nofree; | |
3363 | } | |
3364 | kfree(context); | |
3365 | out_nofree: | |
3366 | return error; | |
1da177e4 LT |
3367 | } |
3368 | ||
3369 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 3370 | const void *value, size_t size, int flags) |
1da177e4 | 3371 | { |
2c97165b | 3372 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
1da177e4 LT |
3373 | u32 newsid; |
3374 | int rc; | |
3375 | ||
3376 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3377 | return -EOPNOTSUPP; | |
3378 | ||
3379 | if (!value || !size) | |
3380 | return -EACCES; | |
3381 | ||
20ba96ae | 3382 | rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); |
1da177e4 LT |
3383 | if (rc) |
3384 | return rc; | |
3385 | ||
9287aed2 | 3386 | spin_lock(&isec->lock); |
aa9c2669 | 3387 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3388 | isec->sid = newsid; |
6f3be9f5 | 3389 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3390 | spin_unlock(&isec->lock); |
1da177e4 LT |
3391 | return 0; |
3392 | } | |
3393 | ||
3394 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3395 | { | |
3396 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3397 | if (buffer && len <= buffer_size) | |
3398 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3399 | return len; | |
3400 | } | |
3401 | ||
d6335d77 | 3402 | static void selinux_inode_getsecid(struct inode *inode, u32 *secid) |
713a04ae | 3403 | { |
e817c2f3 | 3404 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
713a04ae AD |
3405 | *secid = isec->sid; |
3406 | } | |
3407 | ||
56909eb3 VG |
3408 | static int selinux_inode_copy_up(struct dentry *src, struct cred **new) |
3409 | { | |
3410 | u32 sid; | |
3411 | struct task_security_struct *tsec; | |
3412 | struct cred *new_creds = *new; | |
3413 | ||
3414 | if (new_creds == NULL) { | |
3415 | new_creds = prepare_creds(); | |
3416 | if (!new_creds) | |
3417 | return -ENOMEM; | |
3418 | } | |
3419 | ||
3420 | tsec = new_creds->security; | |
3421 | /* Get label from overlay inode and set it in create_sid */ | |
3422 | selinux_inode_getsecid(d_inode(src), &sid); | |
3423 | tsec->create_sid = sid; | |
3424 | *new = new_creds; | |
3425 | return 0; | |
3426 | } | |
3427 | ||
19472b69 VG |
3428 | static int selinux_inode_copy_up_xattr(const char *name) |
3429 | { | |
3430 | /* The copy_up hook above sets the initial context on an inode, but we | |
3431 | * don't then want to overwrite it by blindly copying all the lower | |
3432 | * xattrs up. Instead, we have to filter out SELinux-related xattrs. | |
3433 | */ | |
3434 | if (strcmp(name, XATTR_NAME_SELINUX) == 0) | |
3435 | return 1; /* Discard */ | |
3436 | /* | |
3437 | * Any other attribute apart from SELINUX is not claimed, supported | |
3438 | * by selinux. | |
3439 | */ | |
3440 | return -EOPNOTSUPP; | |
3441 | } | |
3442 | ||
1da177e4 LT |
3443 | /* file security operations */ |
3444 | ||
788e7dd4 | 3445 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3446 | { |
88e67f3b | 3447 | const struct cred *cred = current_cred(); |
496ad9aa | 3448 | struct inode *inode = file_inode(file); |
1da177e4 | 3449 | |
1da177e4 LT |
3450 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3451 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3452 | mask |= MAY_APPEND; | |
3453 | ||
389fb800 PM |
3454 | return file_has_perm(cred, file, |
3455 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3456 | } |
3457 | ||
788e7dd4 YN |
3458 | static int selinux_file_permission(struct file *file, int mask) |
3459 | { | |
496ad9aa | 3460 | struct inode *inode = file_inode(file); |
20dda18b | 3461 | struct file_security_struct *fsec = file->f_security; |
b197367e | 3462 | struct inode_security_struct *isec; |
20dda18b SS |
3463 | u32 sid = current_sid(); |
3464 | ||
389fb800 | 3465 | if (!mask) |
788e7dd4 YN |
3466 | /* No permission to check. Existence test. */ |
3467 | return 0; | |
788e7dd4 | 3468 | |
b197367e | 3469 | isec = inode_security(inode); |
20dda18b SS |
3470 | if (sid == fsec->sid && fsec->isid == isec->sid && |
3471 | fsec->pseqno == avc_policy_seqno()) | |
83d49856 | 3472 | /* No change since file_open check. */ |
20dda18b SS |
3473 | return 0; |
3474 | ||
788e7dd4 YN |
3475 | return selinux_revalidate_file_permission(file, mask); |
3476 | } | |
3477 | ||
1da177e4 LT |
3478 | static int selinux_file_alloc_security(struct file *file) |
3479 | { | |
3480 | return file_alloc_security(file); | |
3481 | } | |
3482 | ||
3483 | static void selinux_file_free_security(struct file *file) | |
3484 | { | |
3485 | file_free_security(file); | |
3486 | } | |
3487 | ||
fa1aa143 JVS |
3488 | /* |
3489 | * Check whether a task has the ioctl permission and cmd | |
3490 | * operation to an inode. | |
3491 | */ | |
1d2a168a | 3492 | static int ioctl_has_perm(const struct cred *cred, struct file *file, |
fa1aa143 JVS |
3493 | u32 requested, u16 cmd) |
3494 | { | |
3495 | struct common_audit_data ad; | |
3496 | struct file_security_struct *fsec = file->f_security; | |
3497 | struct inode *inode = file_inode(file); | |
20cdef8d | 3498 | struct inode_security_struct *isec; |
fa1aa143 JVS |
3499 | struct lsm_ioctlop_audit ioctl; |
3500 | u32 ssid = cred_sid(cred); | |
3501 | int rc; | |
3502 | u8 driver = cmd >> 8; | |
3503 | u8 xperm = cmd & 0xff; | |
3504 | ||
3505 | ad.type = LSM_AUDIT_DATA_IOCTL_OP; | |
3506 | ad.u.op = &ioctl; | |
3507 | ad.u.op->cmd = cmd; | |
3508 | ad.u.op->path = file->f_path; | |
3509 | ||
3510 | if (ssid != fsec->sid) { | |
3511 | rc = avc_has_perm(ssid, fsec->sid, | |
3512 | SECCLASS_FD, | |
3513 | FD__USE, | |
3514 | &ad); | |
3515 | if (rc) | |
3516 | goto out; | |
3517 | } | |
3518 | ||
3519 | if (unlikely(IS_PRIVATE(inode))) | |
3520 | return 0; | |
3521 | ||
20cdef8d | 3522 | isec = inode_security(inode); |
fa1aa143 JVS |
3523 | rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, |
3524 | requested, driver, xperm, &ad); | |
3525 | out: | |
3526 | return rc; | |
3527 | } | |
3528 | ||
1da177e4 LT |
3529 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
3530 | unsigned long arg) | |
3531 | { | |
88e67f3b | 3532 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3533 | int error = 0; |
1da177e4 | 3534 | |
0b24dcb7 EP |
3535 | switch (cmd) { |
3536 | case FIONREAD: | |
3537 | /* fall through */ | |
3538 | case FIBMAP: | |
3539 | /* fall through */ | |
3540 | case FIGETBSZ: | |
3541 | /* fall through */ | |
2f99c369 | 3542 | case FS_IOC_GETFLAGS: |
0b24dcb7 | 3543 | /* fall through */ |
2f99c369 | 3544 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3545 | error = file_has_perm(cred, file, FILE__GETATTR); |
3546 | break; | |
1da177e4 | 3547 | |
2f99c369 | 3548 | case FS_IOC_SETFLAGS: |
0b24dcb7 | 3549 | /* fall through */ |
2f99c369 | 3550 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3551 | error = file_has_perm(cred, file, FILE__SETATTR); |
3552 | break; | |
3553 | ||
3554 | /* sys_ioctl() checks */ | |
3555 | case FIONBIO: | |
3556 | /* fall through */ | |
3557 | case FIOASYNC: | |
3558 | error = file_has_perm(cred, file, 0); | |
3559 | break; | |
1da177e4 | 3560 | |
0b24dcb7 EP |
3561 | case KDSKBENT: |
3562 | case KDSKBSENT: | |
6a9de491 | 3563 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
8e4ff6f2 | 3564 | SECURITY_CAP_AUDIT, true); |
0b24dcb7 EP |
3565 | break; |
3566 | ||
3567 | /* default case assumes that the command will go | |
3568 | * to the file's ioctl() function. | |
3569 | */ | |
3570 | default: | |
fa1aa143 | 3571 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
0b24dcb7 EP |
3572 | } |
3573 | return error; | |
1da177e4 LT |
3574 | } |
3575 | ||
fcaaade1 SS |
3576 | static int default_noexec; |
3577 | ||
1da177e4 LT |
3578 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3579 | { | |
88e67f3b | 3580 | const struct cred *cred = current_cred(); |
d84f4f99 | 3581 | int rc = 0; |
88e67f3b | 3582 | |
fcaaade1 | 3583 | if (default_noexec && |
892e8cac SS |
3584 | (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || |
3585 | (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3586 | /* |
3587 | * We are making executable an anonymous mapping or a | |
3588 | * private file mapping that will also be writable. | |
3589 | * This has an additional check. | |
3590 | */ | |
d84f4f99 | 3591 | rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); |
1da177e4 | 3592 | if (rc) |
d84f4f99 | 3593 | goto error; |
1da177e4 | 3594 | } |
1da177e4 LT |
3595 | |
3596 | if (file) { | |
3597 | /* read access is always possible with a mapping */ | |
3598 | u32 av = FILE__READ; | |
3599 | ||
3600 | /* write access only matters if the mapping is shared */ | |
3601 | if (shared && (prot & PROT_WRITE)) | |
3602 | av |= FILE__WRITE; | |
3603 | ||
3604 | if (prot & PROT_EXEC) | |
3605 | av |= FILE__EXECUTE; | |
3606 | ||
88e67f3b | 3607 | return file_has_perm(cred, file, av); |
1da177e4 | 3608 | } |
d84f4f99 DH |
3609 | |
3610 | error: | |
3611 | return rc; | |
1da177e4 LT |
3612 | } |
3613 | ||
e5467859 | 3614 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3615 | { |
b1d9e6b0 | 3616 | int rc = 0; |
1da177e4 | 3617 | |
a2551df7 | 3618 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
98883bfd | 3619 | u32 sid = current_sid(); |
ed032189 EP |
3620 | rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, |
3621 | MEMPROTECT__MMAP_ZERO, NULL); | |
84336d1a EP |
3622 | } |
3623 | ||
98883bfd | 3624 | return rc; |
e5467859 | 3625 | } |
1da177e4 | 3626 | |
e5467859 AV |
3627 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3628 | unsigned long prot, unsigned long flags) | |
3629 | { | |
1da177e4 LT |
3630 | if (selinux_checkreqprot) |
3631 | prot = reqprot; | |
3632 | ||
3633 | return file_map_prot_check(file, prot, | |
3634 | (flags & MAP_TYPE) == MAP_SHARED); | |
3635 | } | |
3636 | ||
3637 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3638 | unsigned long reqprot, | |
3639 | unsigned long prot) | |
3640 | { | |
88e67f3b | 3641 | const struct cred *cred = current_cred(); |
1da177e4 LT |
3642 | |
3643 | if (selinux_checkreqprot) | |
3644 | prot = reqprot; | |
3645 | ||
fcaaade1 SS |
3646 | if (default_noexec && |
3647 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3648 | int rc = 0; |
db4c9641 SS |
3649 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3650 | vma->vm_end <= vma->vm_mm->brk) { | |
d84f4f99 | 3651 | rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); |
db4c9641 | 3652 | } else if (!vma->vm_file && |
c2316dbf SS |
3653 | ((vma->vm_start <= vma->vm_mm->start_stack && |
3654 | vma->vm_end >= vma->vm_mm->start_stack) || | |
d17af505 | 3655 | vma_is_stack_for_current(vma))) { |
3b11a1de | 3656 | rc = current_has_perm(current, PROCESS__EXECSTACK); |
db4c9641 SS |
3657 | } else if (vma->vm_file && vma->anon_vma) { |
3658 | /* | |
3659 | * We are making executable a file mapping that has | |
3660 | * had some COW done. Since pages might have been | |
3661 | * written, check ability to execute the possibly | |
3662 | * modified content. This typically should only | |
3663 | * occur for text relocations. | |
3664 | */ | |
d84f4f99 | 3665 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3666 | } |