Commit | Line | Data |
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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 | * | |
7efbb60b | 6 | * Authors: Stephen Smalley, <sds@tycho.nsa.gov> |
828dfe1d EP |
7 | * Chris Vance, <cvance@nai.com> |
8 | * Wayne Salamon, <wsalamon@nai.com> | |
9 | * James Morris <jmorris@redhat.com> | |
1da177e4 LT |
10 | * |
11 | * Copyright (C) 2001,2002 Networks Associates Technology, Inc. | |
2069f457 EP |
12 | * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> |
13 | * Eric Paris <eparis@redhat.com> | |
1da177e4 | 14 | * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. |
828dfe1d | 15 | * <dgoeddel@trustedcs.com> |
ed6d76e4 | 16 | * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. |
82c21bfa | 17 | * Paul Moore <paul@paul-moore.com> |
788e7dd4 | 18 | * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. |
828dfe1d | 19 | * Yuichi Nakamura <ynakam@hitachisoft.jp> |
3a976fa6 | 20 | * Copyright (C) 2016 Mellanox Technologies |
1da177e4 LT |
21 | * |
22 | * This program is free software; you can redistribute it and/or modify | |
23 | * it under the terms of the GNU General Public License version 2, | |
828dfe1d | 24 | * as published by the Free Software Foundation. |
1da177e4 LT |
25 | */ |
26 | ||
1da177e4 | 27 | #include <linux/init.h> |
0b24dcb7 | 28 | #include <linux/kd.h> |
1da177e4 | 29 | #include <linux/kernel.h> |
0d094efe | 30 | #include <linux/tracehook.h> |
1da177e4 | 31 | #include <linux/errno.h> |
3f07c014 | 32 | #include <linux/sched/signal.h> |
29930025 | 33 | #include <linux/sched/task.h> |
3c4ed7bd | 34 | #include <linux/lsm_hooks.h> |
1da177e4 LT |
35 | #include <linux/xattr.h> |
36 | #include <linux/capability.h> | |
37 | #include <linux/unistd.h> | |
38 | #include <linux/mm.h> | |
39 | #include <linux/mman.h> | |
40 | #include <linux/slab.h> | |
41 | #include <linux/pagemap.h> | |
0b24dcb7 | 42 | #include <linux/proc_fs.h> |
1da177e4 | 43 | #include <linux/swap.h> |
1da177e4 LT |
44 | #include <linux/spinlock.h> |
45 | #include <linux/syscalls.h> | |
2a7dba39 | 46 | #include <linux/dcache.h> |
1da177e4 | 47 | #include <linux/file.h> |
9f3acc31 | 48 | #include <linux/fdtable.h> |
1da177e4 LT |
49 | #include <linux/namei.h> |
50 | #include <linux/mount.h> | |
1da177e4 LT |
51 | #include <linux/netfilter_ipv4.h> |
52 | #include <linux/netfilter_ipv6.h> | |
53 | #include <linux/tty.h> | |
54 | #include <net/icmp.h> | |
227b60f5 | 55 | #include <net/ip.h> /* for local_port_range[] */ |
1da177e4 | 56 | #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ |
47180068 | 57 | #include <net/inet_connection_sock.h> |
220deb96 | 58 | #include <net/net_namespace.h> |
d621d35e | 59 | #include <net/netlabel.h> |
f5269710 | 60 | #include <linux/uaccess.h> |
1da177e4 | 61 | #include <asm/ioctls.h> |
60063497 | 62 | #include <linux/atomic.h> |
1da177e4 LT |
63 | #include <linux/bitops.h> |
64 | #include <linux/interrupt.h> | |
65 | #include <linux/netdevice.h> /* for network interface checks */ | |
77954983 | 66 | #include <net/netlink.h> |
1da177e4 LT |
67 | #include <linux/tcp.h> |
68 | #include <linux/udp.h> | |
2ee92d46 | 69 | #include <linux/dccp.h> |
d452930f RH |
70 | #include <linux/sctp.h> |
71 | #include <net/sctp/structs.h> | |
1da177e4 LT |
72 | #include <linux/quota.h> |
73 | #include <linux/un.h> /* for Unix socket types */ | |
74 | #include <net/af_unix.h> /* for Unix socket types */ | |
75 | #include <linux/parser.h> | |
76 | #include <linux/nfs_mount.h> | |
77 | #include <net/ipv6.h> | |
78 | #include <linux/hugetlb.h> | |
79 | #include <linux/personality.h> | |
1da177e4 | 80 | #include <linux/audit.h> |
6931dfc9 | 81 | #include <linux/string.h> |
877ce7c1 | 82 | #include <linux/selinux.h> |
23970741 | 83 | #include <linux/mutex.h> |
f06febc9 | 84 | #include <linux/posix-timers.h> |
00234592 | 85 | #include <linux/syslog.h> |
3486740a | 86 | #include <linux/user_namespace.h> |
44fc7ea0 | 87 | #include <linux/export.h> |
40401530 AV |
88 | #include <linux/msg.h> |
89 | #include <linux/shm.h> | |
ec27c356 | 90 | #include <linux/bpf.h> |
1da177e4 LT |
91 | |
92 | #include "avc.h" | |
93 | #include "objsec.h" | |
94 | #include "netif.h" | |
224dfbd8 | 95 | #include "netnode.h" |
3e112172 | 96 | #include "netport.h" |
409dcf31 | 97 | #include "ibpkey.h" |
d28d1e08 | 98 | #include "xfrm.h" |
c60475bf | 99 | #include "netlabel.h" |
9d57a7f9 | 100 | #include "audit.h" |
7b98a585 | 101 | #include "avc_ss.h" |
1da177e4 | 102 | |
aa8e712c SS |
103 | struct selinux_state selinux_state; |
104 | ||
d621d35e | 105 | /* SECMARK reference count */ |
56a4ca99 | 106 | static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); |
d621d35e | 107 | |
1da177e4 | 108 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
aa8e712c | 109 | static int selinux_enforcing_boot; |
1da177e4 LT |
110 | |
111 | static int __init enforcing_setup(char *str) | |
112 | { | |
f5269710 | 113 | unsigned long enforcing; |
29707b20 | 114 | if (!kstrtoul(str, 0, &enforcing)) |
aa8e712c | 115 | selinux_enforcing_boot = enforcing ? 1 : 0; |
1da177e4 LT |
116 | return 1; |
117 | } | |
118 | __setup("enforcing=", enforcing_setup); | |
aa8e712c SS |
119 | #else |
120 | #define selinux_enforcing_boot 1 | |
1da177e4 LT |
121 | #endif |
122 | ||
123 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM | |
124 | int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; | |
125 | ||
126 | static int __init selinux_enabled_setup(char *str) | |
127 | { | |
f5269710 | 128 | unsigned long enabled; |
29707b20 | 129 | if (!kstrtoul(str, 0, &enabled)) |
f5269710 | 130 | selinux_enabled = enabled ? 1 : 0; |
1da177e4 LT |
131 | return 1; |
132 | } | |
133 | __setup("selinux=", selinux_enabled_setup); | |
30d55280 SS |
134 | #else |
135 | int selinux_enabled = 1; | |
1da177e4 LT |
136 | #endif |
137 | ||
aa8e712c SS |
138 | static unsigned int selinux_checkreqprot_boot = |
139 | CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE; | |
140 | ||
141 | static int __init checkreqprot_setup(char *str) | |
142 | { | |
143 | unsigned long checkreqprot; | |
144 | ||
145 | if (!kstrtoul(str, 0, &checkreqprot)) | |
146 | selinux_checkreqprot_boot = checkreqprot ? 1 : 0; | |
147 | return 1; | |
148 | } | |
149 | __setup("checkreqprot=", checkreqprot_setup); | |
150 | ||
e18b890b | 151 | static struct kmem_cache *sel_inode_cache; |
63205654 | 152 | static struct kmem_cache *file_security_cache; |
7cae7e26 | 153 | |
d621d35e PM |
154 | /** |
155 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
156 | * | |
157 | * Description: | |
158 | * This function checks the SECMARK reference counter to see if any SECMARK | |
159 | * targets are currently configured, if the reference counter is greater than | |
160 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
2be4d74f CP |
161 | * enabled, false (0) if SECMARK is disabled. If the always_check_network |
162 | * policy capability is enabled, SECMARK is always considered enabled. | |
d621d35e PM |
163 | * |
164 | */ | |
165 | static int selinux_secmark_enabled(void) | |
166 | { | |
aa8e712c SS |
167 | return (selinux_policycap_alwaysnetwork() || |
168 | atomic_read(&selinux_secmark_refcount)); | |
2be4d74f CP |
169 | } |
170 | ||
171 | /** | |
172 | * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled | |
173 | * | |
174 | * Description: | |
175 | * This function checks if NetLabel or labeled IPSEC is enabled. Returns true | |
176 | * (1) if any are enabled or false (0) if neither are enabled. If the | |
177 | * always_check_network policy capability is enabled, peer labeling | |
178 | * is always considered enabled. | |
179 | * | |
180 | */ | |
181 | static int selinux_peerlbl_enabled(void) | |
182 | { | |
aa8e712c SS |
183 | return (selinux_policycap_alwaysnetwork() || |
184 | netlbl_enabled() || selinux_xfrm_enabled()); | |
d621d35e PM |
185 | } |
186 | ||
615e51fd PM |
187 | static int selinux_netcache_avc_callback(u32 event) |
188 | { | |
189 | if (event == AVC_CALLBACK_RESET) { | |
190 | sel_netif_flush(); | |
191 | sel_netnode_flush(); | |
192 | sel_netport_flush(); | |
193 | synchronize_net(); | |
194 | } | |
195 | return 0; | |
196 | } | |
197 | ||
8f408ab6 DJ |
198 | static int selinux_lsm_notifier_avc_callback(u32 event) |
199 | { | |
409dcf31 DJ |
200 | if (event == AVC_CALLBACK_RESET) { |
201 | sel_ib_pkey_flush(); | |
8f408ab6 | 202 | call_lsm_notifier(LSM_POLICY_CHANGE, NULL); |
409dcf31 | 203 | } |
8f408ab6 DJ |
204 | |
205 | return 0; | |
206 | } | |
207 | ||
d84f4f99 DH |
208 | /* |
209 | * initialise the security for the init task | |
210 | */ | |
211 | static void cred_init_security(void) | |
1da177e4 | 212 | { |
3b11a1de | 213 | struct cred *cred = (struct cred *) current->real_cred; |
1da177e4 LT |
214 | struct task_security_struct *tsec; |
215 | ||
89d155ef | 216 | tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); |
1da177e4 | 217 | if (!tsec) |
d84f4f99 | 218 | panic("SELinux: Failed to initialize initial task.\n"); |
1da177e4 | 219 | |
d84f4f99 | 220 | tsec->osid = tsec->sid = SECINITSID_KERNEL; |
f1752eec | 221 | cred->security = tsec; |
1da177e4 LT |
222 | } |
223 | ||
88e67f3b DH |
224 | /* |
225 | * get the security ID of a set of credentials | |
226 | */ | |
227 | static inline u32 cred_sid(const struct cred *cred) | |
228 | { | |
229 | const struct task_security_struct *tsec; | |
230 | ||
231 | tsec = cred->security; | |
232 | return tsec->sid; | |
233 | } | |
234 | ||
275bb41e | 235 | /* |
3b11a1de | 236 | * get the objective security ID of a task |
275bb41e DH |
237 | */ |
238 | static inline u32 task_sid(const struct task_struct *task) | |
239 | { | |
275bb41e DH |
240 | u32 sid; |
241 | ||
242 | rcu_read_lock(); | |
88e67f3b | 243 | sid = cred_sid(__task_cred(task)); |
275bb41e DH |
244 | rcu_read_unlock(); |
245 | return sid; | |
246 | } | |
247 | ||
88e67f3b DH |
248 | /* Allocate and free functions for each kind of security blob. */ |
249 | ||
1da177e4 LT |
250 | static int inode_alloc_security(struct inode *inode) |
251 | { | |
1da177e4 | 252 | struct inode_security_struct *isec; |
275bb41e | 253 | u32 sid = current_sid(); |
1da177e4 | 254 | |
a02fe132 | 255 | isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); |
1da177e4 LT |
256 | if (!isec) |
257 | return -ENOMEM; | |
258 | ||
9287aed2 | 259 | spin_lock_init(&isec->lock); |
1da177e4 | 260 | INIT_LIST_HEAD(&isec->list); |
1da177e4 LT |
261 | isec->inode = inode; |
262 | isec->sid = SECINITSID_UNLABELED; | |
263 | isec->sclass = SECCLASS_FILE; | |
275bb41e | 264 | isec->task_sid = sid; |
42059112 | 265 | isec->initialized = LABEL_INVALID; |
1da177e4 LT |
266 | inode->i_security = isec; |
267 | ||
268 | return 0; | |
269 | } | |
270 | ||
5d226df4 AG |
271 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); |
272 | ||
273 | /* | |
274 | * Try reloading inode security labels that have been marked as invalid. The | |
275 | * @may_sleep parameter indicates when sleeping and thus reloading labels is | |
42059112 | 276 | * allowed; when set to false, returns -ECHILD when the label is |
5d226df4 AG |
277 | * invalid. The @opt_dentry parameter should be set to a dentry of the inode; |
278 | * when no dentry is available, set it to NULL instead. | |
279 | */ | |
280 | static int __inode_security_revalidate(struct inode *inode, | |
281 | struct dentry *opt_dentry, | |
282 | bool may_sleep) | |
283 | { | |
284 | struct inode_security_struct *isec = inode->i_security; | |
285 | ||
286 | might_sleep_if(may_sleep); | |
287 | ||
aa8e712c SS |
288 | if (selinux_state.initialized && |
289 | isec->initialized != LABEL_INITIALIZED) { | |
5d226df4 AG |
290 | if (!may_sleep) |
291 | return -ECHILD; | |
292 | ||
293 | /* | |
294 | * Try reloading the inode security label. This will fail if | |
295 | * @opt_dentry is NULL and no dentry for this inode can be | |
296 | * found; in that case, continue using the old label. | |
297 | */ | |
298 | inode_doinit_with_dentry(inode, opt_dentry); | |
299 | } | |
300 | return 0; | |
301 | } | |
302 | ||
5d226df4 AG |
303 | static struct inode_security_struct *inode_security_novalidate(struct inode *inode) |
304 | { | |
305 | return inode->i_security; | |
306 | } | |
307 | ||
308 | static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) | |
309 | { | |
310 | int error; | |
311 | ||
312 | error = __inode_security_revalidate(inode, NULL, !rcu); | |
313 | if (error) | |
314 | return ERR_PTR(error); | |
315 | return inode->i_security; | |
316 | } | |
317 | ||
83da53c5 AG |
318 | /* |
319 | * Get the security label of an inode. | |
320 | */ | |
321 | static struct inode_security_struct *inode_security(struct inode *inode) | |
322 | { | |
5d226df4 | 323 | __inode_security_revalidate(inode, NULL, true); |
83da53c5 AG |
324 | return inode->i_security; |
325 | } | |
326 | ||
2c97165b PM |
327 | static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) |
328 | { | |
329 | struct inode *inode = d_backing_inode(dentry); | |
330 | ||
331 | return inode->i_security; | |
332 | } | |
333 | ||
83da53c5 AG |
334 | /* |
335 | * Get the security label of a dentry's backing inode. | |
336 | */ | |
337 | static struct inode_security_struct *backing_inode_security(struct dentry *dentry) | |
338 | { | |
339 | struct inode *inode = d_backing_inode(dentry); | |
340 | ||
5d226df4 | 341 | __inode_security_revalidate(inode, dentry, true); |
83da53c5 AG |
342 | return inode->i_security; |
343 | } | |
344 | ||
3dc91d43 SR |
345 | static void inode_free_rcu(struct rcu_head *head) |
346 | { | |
347 | struct inode_security_struct *isec; | |
348 | ||
349 | isec = container_of(head, struct inode_security_struct, rcu); | |
350 | kmem_cache_free(sel_inode_cache, isec); | |
351 | } | |
352 | ||
1da177e4 LT |
353 | static void inode_free_security(struct inode *inode) |
354 | { | |
355 | struct inode_security_struct *isec = inode->i_security; | |
356 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
357 | ||
9629d04a WL |
358 | /* |
359 | * As not all inode security structures are in a list, we check for | |
360 | * empty list outside of the lock to make sure that we won't waste | |
361 | * time taking a lock doing nothing. | |
362 | * | |
363 | * The list_del_init() function can be safely called more than once. | |
364 | * It should not be possible for this function to be called with | |
365 | * concurrent list_add(), but for better safety against future changes | |
366 | * in the code, we use list_empty_careful() here. | |
367 | */ | |
368 | if (!list_empty_careful(&isec->list)) { | |
369 | spin_lock(&sbsec->isec_lock); | |
1da177e4 | 370 | list_del_init(&isec->list); |
9629d04a WL |
371 | spin_unlock(&sbsec->isec_lock); |
372 | } | |
1da177e4 | 373 | |
3dc91d43 SR |
374 | /* |
375 | * The inode may still be referenced in a path walk and | |
376 | * a call to selinux_inode_permission() can be made | |
377 | * after inode_free_security() is called. Ideally, the VFS | |
378 | * wouldn't do this, but fixing that is a much harder | |
379 | * job. For now, simply free the i_security via RCU, and | |
380 | * leave the current inode->i_security pointer intact. | |
381 | * The inode will be freed after the RCU grace period too. | |
382 | */ | |
383 | call_rcu(&isec->rcu, inode_free_rcu); | |
1da177e4 LT |
384 | } |
385 | ||
386 | static int file_alloc_security(struct file *file) | |
387 | { | |
1da177e4 | 388 | struct file_security_struct *fsec; |
275bb41e | 389 | u32 sid = current_sid(); |
1da177e4 | 390 | |
63205654 | 391 | fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL); |
1da177e4 LT |
392 | if (!fsec) |
393 | return -ENOMEM; | |
394 | ||
275bb41e DH |
395 | fsec->sid = sid; |
396 | fsec->fown_sid = sid; | |
1da177e4 LT |
397 | file->f_security = fsec; |
398 | ||
399 | return 0; | |
400 | } | |
401 | ||
402 | static void file_free_security(struct file *file) | |
403 | { | |
404 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 | 405 | file->f_security = NULL; |
63205654 | 406 | kmem_cache_free(file_security_cache, fsec); |
1da177e4 LT |
407 | } |
408 | ||
409 | static int superblock_alloc_security(struct super_block *sb) | |
410 | { | |
411 | struct superblock_security_struct *sbsec; | |
412 | ||
89d155ef | 413 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
414 | if (!sbsec) |
415 | return -ENOMEM; | |
416 | ||
bc7e982b | 417 | mutex_init(&sbsec->lock); |
1da177e4 LT |
418 | INIT_LIST_HEAD(&sbsec->isec_head); |
419 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
420 | sbsec->sb = sb; |
421 | sbsec->sid = SECINITSID_UNLABELED; | |
422 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 423 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
424 | sb->s_security = sbsec; |
425 | ||
426 | return 0; | |
427 | } | |
428 | ||
429 | static void superblock_free_security(struct super_block *sb) | |
430 | { | |
431 | struct superblock_security_struct *sbsec = sb->s_security; | |
1da177e4 LT |
432 | sb->s_security = NULL; |
433 | kfree(sbsec); | |
434 | } | |
435 | ||
1da177e4 LT |
436 | static inline int inode_doinit(struct inode *inode) |
437 | { | |
438 | return inode_doinit_with_dentry(inode, NULL); | |
439 | } | |
440 | ||
441 | enum { | |
31e87930 | 442 | Opt_error = -1, |
1da177e4 LT |
443 | Opt_context = 1, |
444 | Opt_fscontext = 2, | |
c9180a57 EP |
445 | Opt_defcontext = 3, |
446 | Opt_rootcontext = 4, | |
11689d47 | 447 | Opt_labelsupport = 5, |
d355987f | 448 | Opt_nextmntopt = 6, |
1da177e4 LT |
449 | }; |
450 | ||
d355987f EP |
451 | #define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) |
452 | ||
a447c093 | 453 | static const match_table_t tokens = { |
832cbd9a EP |
454 | {Opt_context, CONTEXT_STR "%s"}, |
455 | {Opt_fscontext, FSCONTEXT_STR "%s"}, | |
456 | {Opt_defcontext, DEFCONTEXT_STR "%s"}, | |
457 | {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, | |
11689d47 | 458 | {Opt_labelsupport, LABELSUPP_STR}, |
31e87930 | 459 | {Opt_error, NULL}, |
1da177e4 LT |
460 | }; |
461 | ||
462 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
463 | ||
c312feb2 EP |
464 | static int may_context_mount_sb_relabel(u32 sid, |
465 | struct superblock_security_struct *sbsec, | |
275bb41e | 466 | const struct cred *cred) |
c312feb2 | 467 | { |
275bb41e | 468 | const struct task_security_struct *tsec = cred->security; |
c312feb2 EP |
469 | int rc; |
470 | ||
6b6bc620 SS |
471 | rc = avc_has_perm(&selinux_state, |
472 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
473 | FILESYSTEM__RELABELFROM, NULL); |
474 | if (rc) | |
475 | return rc; | |
476 | ||
6b6bc620 SS |
477 | rc = avc_has_perm(&selinux_state, |
478 | tsec->sid, sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
479 | FILESYSTEM__RELABELTO, NULL); |
480 | return rc; | |
481 | } | |
482 | ||
0808925e EP |
483 | static int may_context_mount_inode_relabel(u32 sid, |
484 | struct superblock_security_struct *sbsec, | |
275bb41e | 485 | const struct cred *cred) |
0808925e | 486 | { |
275bb41e | 487 | const struct task_security_struct *tsec = cred->security; |
0808925e | 488 | int rc; |
6b6bc620 SS |
489 | rc = avc_has_perm(&selinux_state, |
490 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
491 | FILESYSTEM__RELABELFROM, NULL); |
492 | if (rc) | |
493 | return rc; | |
494 | ||
6b6bc620 SS |
495 | rc = avc_has_perm(&selinux_state, |
496 | sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
497 | FILESYSTEM__ASSOCIATE, NULL); |
498 | return rc; | |
499 | } | |
500 | ||
b43e725d EP |
501 | static int selinux_is_sblabel_mnt(struct super_block *sb) |
502 | { | |
503 | struct superblock_security_struct *sbsec = sb->s_security; | |
504 | ||
d5f3a5f6 MS |
505 | return sbsec->behavior == SECURITY_FS_USE_XATTR || |
506 | sbsec->behavior == SECURITY_FS_USE_TRANS || | |
507 | sbsec->behavior == SECURITY_FS_USE_TASK || | |
9fc2b4b4 | 508 | sbsec->behavior == SECURITY_FS_USE_NATIVE || |
d5f3a5f6 MS |
509 | /* Special handling. Genfs but also in-core setxattr handler */ |
510 | !strcmp(sb->s_type->name, "sysfs") || | |
511 | !strcmp(sb->s_type->name, "pstore") || | |
512 | !strcmp(sb->s_type->name, "debugfs") || | |
a2c7c6fb | 513 | !strcmp(sb->s_type->name, "tracefs") || |
2651225b | 514 | !strcmp(sb->s_type->name, "rootfs") || |
aa8e712c | 515 | (selinux_policycap_cgroupseclabel() && |
2651225b SS |
516 | (!strcmp(sb->s_type->name, "cgroup") || |
517 | !strcmp(sb->s_type->name, "cgroup2"))); | |
b43e725d EP |
518 | } |
519 | ||
c9180a57 | 520 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 521 | { |
1da177e4 | 522 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 | 523 | struct dentry *root = sb->s_root; |
c6f493d6 | 524 | struct inode *root_inode = d_backing_inode(root); |
c9180a57 | 525 | int rc = 0; |
1da177e4 | 526 | |
c9180a57 EP |
527 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
528 | /* Make sure that the xattr handler exists and that no | |
529 | error other than -ENODATA is returned by getxattr on | |
530 | the root directory. -ENODATA is ok, as this may be | |
531 | the first boot of the SELinux kernel before we have | |
532 | assigned xattr values to the filesystem. */ | |
5d6c3191 | 533 | if (!(root_inode->i_opflags & IOP_XATTR)) { |
29b1deb2 LT |
534 | printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " |
535 | "xattr support\n", sb->s_id, sb->s_type->name); | |
c9180a57 EP |
536 | rc = -EOPNOTSUPP; |
537 | goto out; | |
538 | } | |
5d6c3191 AG |
539 | |
540 | rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); | |
c9180a57 EP |
541 | if (rc < 0 && rc != -ENODATA) { |
542 | if (rc == -EOPNOTSUPP) | |
543 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
29b1deb2 LT |
544 | "%s) has no security xattr handler\n", |
545 | sb->s_id, sb->s_type->name); | |
c9180a57 EP |
546 | else |
547 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
29b1deb2 LT |
548 | "%s) getxattr errno %d\n", sb->s_id, |
549 | sb->s_type->name, -rc); | |
c9180a57 EP |
550 | goto out; |
551 | } | |
552 | } | |
1da177e4 | 553 | |
eadcabc6 | 554 | sbsec->flags |= SE_SBINITIALIZED; |
0b4d3452 SM |
555 | |
556 | /* | |
557 | * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply | |
558 | * leave the flag untouched because sb_clone_mnt_opts might be handing | |
559 | * us a superblock that needs the flag to be cleared. | |
560 | */ | |
b43e725d | 561 | if (selinux_is_sblabel_mnt(sb)) |
12f348b9 | 562 | sbsec->flags |= SBLABEL_MNT; |
0b4d3452 SM |
563 | else |
564 | sbsec->flags &= ~SBLABEL_MNT; | |
ddd29ec6 | 565 | |
c9180a57 EP |
566 | /* Initialize the root inode. */ |
567 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 568 | |
c9180a57 EP |
569 | /* Initialize any other inodes associated with the superblock, e.g. |
570 | inodes created prior to initial policy load or inodes created | |
571 | during get_sb by a pseudo filesystem that directly | |
572 | populates itself. */ | |
573 | spin_lock(&sbsec->isec_lock); | |
574 | next_inode: | |
575 | if (!list_empty(&sbsec->isec_head)) { | |
576 | struct inode_security_struct *isec = | |
577 | list_entry(sbsec->isec_head.next, | |
578 | struct inode_security_struct, list); | |
579 | struct inode *inode = isec->inode; | |
923190d3 | 580 | list_del_init(&isec->list); |
c9180a57 EP |
581 | spin_unlock(&sbsec->isec_lock); |
582 | inode = igrab(inode); | |
583 | if (inode) { | |
584 | if (!IS_PRIVATE(inode)) | |
585 | inode_doinit(inode); | |
586 | iput(inode); | |
587 | } | |
588 | spin_lock(&sbsec->isec_lock); | |
c9180a57 EP |
589 | goto next_inode; |
590 | } | |
591 | spin_unlock(&sbsec->isec_lock); | |
592 | out: | |
593 | return rc; | |
594 | } | |
1da177e4 | 595 | |
c9180a57 EP |
596 | /* |
597 | * This function should allow an FS to ask what it's mount security | |
598 | * options were so it can use those later for submounts, displaying | |
599 | * mount options, or whatever. | |
600 | */ | |
601 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
e0007529 | 602 | struct security_mnt_opts *opts) |
c9180a57 EP |
603 | { |
604 | int rc = 0, i; | |
605 | struct superblock_security_struct *sbsec = sb->s_security; | |
606 | char *context = NULL; | |
607 | u32 len; | |
608 | char tmp; | |
1da177e4 | 609 | |
e0007529 | 610 | security_init_mnt_opts(opts); |
1da177e4 | 611 | |
0d90a7ec | 612 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
c9180a57 | 613 | return -EINVAL; |
1da177e4 | 614 | |
aa8e712c | 615 | if (!selinux_state.initialized) |
c9180a57 | 616 | return -EINVAL; |
1da177e4 | 617 | |
af8e50cc EP |
618 | /* make sure we always check enough bits to cover the mask */ |
619 | BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); | |
620 | ||
0d90a7ec | 621 | tmp = sbsec->flags & SE_MNTMASK; |
c9180a57 | 622 | /* count the number of mount options for this sb */ |
af8e50cc | 623 | for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { |
c9180a57 | 624 | if (tmp & 0x01) |
e0007529 | 625 | opts->num_mnt_opts++; |
c9180a57 EP |
626 | tmp >>= 1; |
627 | } | |
11689d47 | 628 | /* Check if the Label support flag is set */ |
0b4bdb35 | 629 | if (sbsec->flags & SBLABEL_MNT) |
11689d47 | 630 | opts->num_mnt_opts++; |
1da177e4 | 631 | |
e0007529 EP |
632 | opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); |
633 | if (!opts->mnt_opts) { | |
c9180a57 EP |
634 | rc = -ENOMEM; |
635 | goto out_free; | |
636 | } | |
1da177e4 | 637 | |
e0007529 EP |
638 | opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); |
639 | if (!opts->mnt_opts_flags) { | |
c9180a57 EP |
640 | rc = -ENOMEM; |
641 | goto out_free; | |
642 | } | |
1da177e4 | 643 | |
c9180a57 EP |
644 | i = 0; |
645 | if (sbsec->flags & FSCONTEXT_MNT) { | |
aa8e712c SS |
646 | rc = security_sid_to_context(&selinux_state, sbsec->sid, |
647 | &context, &len); | |
c9180a57 EP |
648 | if (rc) |
649 | goto out_free; | |
e0007529 EP |
650 | opts->mnt_opts[i] = context; |
651 | opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; | |
c9180a57 EP |
652 | } |
653 | if (sbsec->flags & CONTEXT_MNT) { | |
aa8e712c SS |
654 | rc = security_sid_to_context(&selinux_state, |
655 | sbsec->mntpoint_sid, | |
656 | &context, &len); | |
c9180a57 EP |
657 | if (rc) |
658 | goto out_free; | |
e0007529 EP |
659 | opts->mnt_opts[i] = context; |
660 | opts->mnt_opts_flags[i++] = CONTEXT_MNT; | |
c9180a57 EP |
661 | } |
662 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
aa8e712c SS |
663 | rc = security_sid_to_context(&selinux_state, sbsec->def_sid, |
664 | &context, &len); | |
c9180a57 EP |
665 | if (rc) |
666 | goto out_free; | |
e0007529 EP |
667 | opts->mnt_opts[i] = context; |
668 | opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
669 | } |
670 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
671 | struct dentry *root = sbsec->sb->s_root; |
672 | struct inode_security_struct *isec = backing_inode_security(root); | |
0808925e | 673 | |
aa8e712c SS |
674 | rc = security_sid_to_context(&selinux_state, isec->sid, |
675 | &context, &len); | |
c9180a57 EP |
676 | if (rc) |
677 | goto out_free; | |
e0007529 EP |
678 | opts->mnt_opts[i] = context; |
679 | opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; | |
c9180a57 | 680 | } |
12f348b9 | 681 | if (sbsec->flags & SBLABEL_MNT) { |
11689d47 | 682 | opts->mnt_opts[i] = NULL; |
12f348b9 | 683 | opts->mnt_opts_flags[i++] = SBLABEL_MNT; |
11689d47 | 684 | } |
1da177e4 | 685 | |
e0007529 | 686 | BUG_ON(i != opts->num_mnt_opts); |
1da177e4 | 687 | |
c9180a57 EP |
688 | return 0; |
689 | ||
690 | out_free: | |
e0007529 | 691 | security_free_mnt_opts(opts); |
c9180a57 EP |
692 | return rc; |
693 | } | |
1da177e4 | 694 | |
c9180a57 EP |
695 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
696 | u32 old_sid, u32 new_sid) | |
697 | { | |
0d90a7ec DQ |
698 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
699 | ||
c9180a57 | 700 | /* check if the old mount command had the same options */ |
0d90a7ec | 701 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
702 | if (!(sbsec->flags & flag) || |
703 | (old_sid != new_sid)) | |
704 | return 1; | |
705 | ||
706 | /* check if we were passed the same options twice, | |
707 | * aka someone passed context=a,context=b | |
708 | */ | |
0d90a7ec DQ |
709 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
710 | if (mnt_flags & flag) | |
c9180a57 EP |
711 | return 1; |
712 | return 0; | |
713 | } | |
e0007529 | 714 | |
c9180a57 EP |
715 | /* |
716 | * Allow filesystems with binary mount data to explicitly set mount point | |
717 | * labeling information. | |
718 | */ | |
e0007529 | 719 | static int selinux_set_mnt_opts(struct super_block *sb, |
649f6e77 DQ |
720 | struct security_mnt_opts *opts, |
721 | unsigned long kern_flags, | |
722 | unsigned long *set_kern_flags) | |
c9180a57 | 723 | { |
275bb41e | 724 | const struct cred *cred = current_cred(); |
c9180a57 | 725 | int rc = 0, i; |
c9180a57 | 726 | struct superblock_security_struct *sbsec = sb->s_security; |
29b1deb2 | 727 | const char *name = sb->s_type->name; |
83da53c5 | 728 | struct dentry *root = sbsec->sb->s_root; |
2c97165b | 729 | struct inode_security_struct *root_isec; |
c9180a57 EP |
730 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
731 | u32 defcontext_sid = 0; | |
e0007529 EP |
732 | char **mount_options = opts->mnt_opts; |
733 | int *flags = opts->mnt_opts_flags; | |
734 | int num_opts = opts->num_mnt_opts; | |
c9180a57 EP |
735 | |
736 | mutex_lock(&sbsec->lock); | |
737 | ||
aa8e712c | 738 | if (!selinux_state.initialized) { |
c9180a57 EP |
739 | if (!num_opts) { |
740 | /* Defer initialization until selinux_complete_init, | |
741 | after the initial policy is loaded and the security | |
742 | server is ready to handle calls. */ | |
c9180a57 EP |
743 | goto out; |
744 | } | |
745 | rc = -EINVAL; | |
744ba35e EP |
746 | printk(KERN_WARNING "SELinux: Unable to set superblock options " |
747 | "before the security server is initialized\n"); | |
1da177e4 | 748 | goto out; |
c9180a57 | 749 | } |
649f6e77 DQ |
750 | if (kern_flags && !set_kern_flags) { |
751 | /* Specifying internal flags without providing a place to | |
752 | * place the results is not allowed */ | |
753 | rc = -EINVAL; | |
754 | goto out; | |
755 | } | |
1da177e4 | 756 | |
e0007529 EP |
757 | /* |
758 | * Binary mount data FS will come through this function twice. Once | |
759 | * from an explicit call and once from the generic calls from the vfs. | |
760 | * Since the generic VFS calls will not contain any security mount data | |
761 | * we need to skip the double mount verification. | |
762 | * | |
763 | * This does open a hole in which we will not notice if the first | |
764 | * mount using this sb set explict options and a second mount using | |
765 | * this sb does not set any security options. (The first options | |
766 | * will be used for both mounts) | |
767 | */ | |
0d90a7ec | 768 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
e0007529 | 769 | && (num_opts == 0)) |
f5269710 | 770 | goto out; |
e0007529 | 771 | |
2c97165b PM |
772 | root_isec = backing_inode_security_novalidate(root); |
773 | ||
c9180a57 EP |
774 | /* |
775 | * parse the mount options, check if they are valid sids. | |
776 | * also check if someone is trying to mount the same sb more | |
777 | * than once with different security options. | |
778 | */ | |
779 | for (i = 0; i < num_opts; i++) { | |
780 | u32 sid; | |
11689d47 | 781 | |
12f348b9 | 782 | if (flags[i] == SBLABEL_MNT) |
11689d47 | 783 | continue; |
aa8e712c SS |
784 | rc = security_context_str_to_sid(&selinux_state, |
785 | mount_options[i], &sid, | |
786 | GFP_KERNEL); | |
1da177e4 | 787 | if (rc) { |
44be2f65 | 788 | printk(KERN_WARNING "SELinux: security_context_str_to_sid" |
29b1deb2 LT |
789 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
790 | mount_options[i], sb->s_id, name, rc); | |
c9180a57 EP |
791 | goto out; |
792 | } | |
793 | switch (flags[i]) { | |
794 | case FSCONTEXT_MNT: | |
795 | fscontext_sid = sid; | |
796 | ||
797 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
798 | fscontext_sid)) | |
799 | goto out_double_mount; | |
800 | ||
801 | sbsec->flags |= FSCONTEXT_MNT; | |
802 | break; | |
803 | case CONTEXT_MNT: | |
804 | context_sid = sid; | |
805 | ||
806 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
807 | context_sid)) | |
808 | goto out_double_mount; | |
809 | ||
810 | sbsec->flags |= CONTEXT_MNT; | |
811 | break; | |
812 | case ROOTCONTEXT_MNT: | |
813 | rootcontext_sid = sid; | |
814 | ||
815 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
816 | rootcontext_sid)) | |
817 | goto out_double_mount; | |
818 | ||
819 | sbsec->flags |= ROOTCONTEXT_MNT; | |
820 | ||
821 | break; | |
822 | case DEFCONTEXT_MNT: | |
823 | defcontext_sid = sid; | |
824 | ||
825 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
826 | defcontext_sid)) | |
827 | goto out_double_mount; | |
828 | ||
829 | sbsec->flags |= DEFCONTEXT_MNT; | |
830 | ||
831 | break; | |
832 | default: | |
833 | rc = -EINVAL; | |
834 | goto out; | |
1da177e4 | 835 | } |
c9180a57 EP |
836 | } |
837 | ||
0d90a7ec | 838 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 839 | /* previously mounted with options, but not on this attempt? */ |
0d90a7ec | 840 | if ((sbsec->flags & SE_MNTMASK) && !num_opts) |
c9180a57 EP |
841 | goto out_double_mount; |
842 | rc = 0; | |
843 | goto out; | |
844 | } | |
845 | ||
089be43e | 846 | if (strcmp(sb->s_type->name, "proc") == 0) |
134509d5 SS |
847 | sbsec->flags |= SE_SBPROC | SE_SBGENFS; |
848 | ||
8e014720 | 849 | if (!strcmp(sb->s_type->name, "debugfs") || |
6a391183 | 850 | !strcmp(sb->s_type->name, "tracefs") || |
8e014720 | 851 | !strcmp(sb->s_type->name, "sysfs") || |
901ef845 AM |
852 | !strcmp(sb->s_type->name, "pstore") || |
853 | !strcmp(sb->s_type->name, "cgroup") || | |
854 | !strcmp(sb->s_type->name, "cgroup2")) | |
134509d5 | 855 | sbsec->flags |= SE_SBGENFS; |
c9180a57 | 856 | |
eb9ae686 DQ |
857 | if (!sbsec->behavior) { |
858 | /* | |
859 | * Determine the labeling behavior to use for this | |
860 | * filesystem type. | |
861 | */ | |
aa8e712c | 862 | rc = security_fs_use(&selinux_state, sb); |
eb9ae686 DQ |
863 | if (rc) { |
864 | printk(KERN_WARNING | |
865 | "%s: security_fs_use(%s) returned %d\n", | |
866 | __func__, sb->s_type->name, rc); | |
867 | goto out; | |
868 | } | |
c9180a57 | 869 | } |
aad82892 SF |
870 | |
871 | /* | |
01593d32 SS |
872 | * If this is a user namespace mount and the filesystem type is not |
873 | * explicitly whitelisted, then no contexts are allowed on the command | |
874 | * line and security labels must be ignored. | |
aad82892 | 875 | */ |
01593d32 SS |
876 | if (sb->s_user_ns != &init_user_ns && |
877 | strcmp(sb->s_type->name, "tmpfs") && | |
878 | strcmp(sb->s_type->name, "ramfs") && | |
879 | strcmp(sb->s_type->name, "devpts")) { | |
aad82892 SF |
880 | if (context_sid || fscontext_sid || rootcontext_sid || |
881 | defcontext_sid) { | |
882 | rc = -EACCES; | |
883 | goto out; | |
884 | } | |
885 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { | |
886 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; | |
aa8e712c SS |
887 | rc = security_transition_sid(&selinux_state, |
888 | current_sid(), | |
889 | current_sid(), | |
aad82892 SF |
890 | SECCLASS_FILE, NULL, |
891 | &sbsec->mntpoint_sid); | |
892 | if (rc) | |
893 | goto out; | |
894 | } | |
895 | goto out_set_opts; | |
896 | } | |
897 | ||
c9180a57 EP |
898 | /* sets the context of the superblock for the fs being mounted. */ |
899 | if (fscontext_sid) { | |
275bb41e | 900 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
1da177e4 | 901 | if (rc) |
c9180a57 | 902 | goto out; |
1da177e4 | 903 | |
c9180a57 | 904 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
905 | } |
906 | ||
907 | /* | |
908 | * Switch to using mount point labeling behavior. | |
909 | * sets the label used on all file below the mountpoint, and will set | |
910 | * the superblock context if not already set. | |
911 | */ | |
eb9ae686 DQ |
912 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { |
913 | sbsec->behavior = SECURITY_FS_USE_NATIVE; | |
914 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
915 | } | |
916 | ||
c9180a57 EP |
917 | if (context_sid) { |
918 | if (!fscontext_sid) { | |
275bb41e DH |
919 | rc = may_context_mount_sb_relabel(context_sid, sbsec, |
920 | cred); | |
b04ea3ce | 921 | if (rc) |
c9180a57 EP |
922 | goto out; |
923 | sbsec->sid = context_sid; | |
b04ea3ce | 924 | } else { |
275bb41e DH |
925 | rc = may_context_mount_inode_relabel(context_sid, sbsec, |
926 | cred); | |
b04ea3ce | 927 | if (rc) |
c9180a57 | 928 | goto out; |
b04ea3ce | 929 | } |
c9180a57 EP |
930 | if (!rootcontext_sid) |
931 | rootcontext_sid = context_sid; | |
1da177e4 | 932 | |
c9180a57 | 933 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 934 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
935 | } |
936 | ||
c9180a57 | 937 | if (rootcontext_sid) { |
275bb41e DH |
938 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
939 | cred); | |
0808925e | 940 | if (rc) |
c9180a57 | 941 | goto out; |
0808925e | 942 | |
c9180a57 | 943 | root_isec->sid = rootcontext_sid; |
6f3be9f5 | 944 | root_isec->initialized = LABEL_INITIALIZED; |
0808925e EP |
945 | } |
946 | ||
c9180a57 | 947 | if (defcontext_sid) { |
eb9ae686 DQ |
948 | if (sbsec->behavior != SECURITY_FS_USE_XATTR && |
949 | sbsec->behavior != SECURITY_FS_USE_NATIVE) { | |
c9180a57 EP |
950 | rc = -EINVAL; |
951 | printk(KERN_WARNING "SELinux: defcontext option is " | |
952 | "invalid for this filesystem type\n"); | |
953 | goto out; | |
1da177e4 LT |
954 | } |
955 | ||
c9180a57 EP |
956 | if (defcontext_sid != sbsec->def_sid) { |
957 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
275bb41e | 958 | sbsec, cred); |
c9180a57 EP |
959 | if (rc) |
960 | goto out; | |
961 | } | |
1da177e4 | 962 | |
c9180a57 | 963 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
964 | } |
965 | ||
aad82892 | 966 | out_set_opts: |
c9180a57 | 967 | rc = sb_finish_set_opts(sb); |
1da177e4 | 968 | out: |
c9180a57 | 969 | mutex_unlock(&sbsec->lock); |
1da177e4 | 970 | return rc; |
c9180a57 EP |
971 | out_double_mount: |
972 | rc = -EINVAL; | |
973 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " | |
29b1deb2 | 974 | "security settings for (dev %s, type %s)\n", sb->s_id, name); |
c9180a57 | 975 | goto out; |
1da177e4 LT |
976 | } |
977 | ||
094f7b69 JL |
978 | static int selinux_cmp_sb_context(const struct super_block *oldsb, |
979 | const struct super_block *newsb) | |
980 | { | |
981 | struct superblock_security_struct *old = oldsb->s_security; | |
982 | struct superblock_security_struct *new = newsb->s_security; | |
983 | char oldflags = old->flags & SE_MNTMASK; | |
984 | char newflags = new->flags & SE_MNTMASK; | |
985 | ||
986 | if (oldflags != newflags) | |
987 | goto mismatch; | |
988 | if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) | |
989 | goto mismatch; | |
990 | if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) | |
991 | goto mismatch; | |
992 | if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) | |
993 | goto mismatch; | |
994 | if (oldflags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
995 | struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); |
996 | struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); | |
094f7b69 JL |
997 | if (oldroot->sid != newroot->sid) |
998 | goto mismatch; | |
999 | } | |
1000 | return 0; | |
1001 | mismatch: | |
1002 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " | |
1003 | "different security settings for (dev %s, " | |
1004 | "type %s)\n", newsb->s_id, newsb->s_type->name); | |
1005 | return -EBUSY; | |
1006 | } | |
1007 | ||
1008 | static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, | |
0b4d3452 SM |
1009 | struct super_block *newsb, |
1010 | unsigned long kern_flags, | |
1011 | unsigned long *set_kern_flags) | |
1da177e4 | 1012 | { |
0b4d3452 | 1013 | int rc = 0; |
c9180a57 EP |
1014 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
1015 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 1016 | |
c9180a57 EP |
1017 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
1018 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
1019 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 1020 | |
0f5e6420 EP |
1021 | /* |
1022 | * if the parent was able to be mounted it clearly had no special lsm | |
e8c26255 | 1023 | * mount options. thus we can safely deal with this superblock later |
0f5e6420 | 1024 | */ |
aa8e712c | 1025 | if (!selinux_state.initialized) |
094f7b69 | 1026 | return 0; |
c9180a57 | 1027 | |
0b4d3452 SM |
1028 | /* |
1029 | * Specifying internal flags without providing a place to | |
1030 | * place the results is not allowed. | |
1031 | */ | |
1032 | if (kern_flags && !set_kern_flags) | |
1033 | return -EINVAL; | |
1034 | ||
c9180a57 | 1035 | /* how can we clone if the old one wasn't set up?? */ |
0d90a7ec | 1036 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
c9180a57 | 1037 | |
094f7b69 | 1038 | /* if fs is reusing a sb, make sure that the contexts match */ |
0d90a7ec | 1039 | if (newsbsec->flags & SE_SBINITIALIZED) |
094f7b69 | 1040 | return selinux_cmp_sb_context(oldsb, newsb); |
5a552617 | 1041 | |
c9180a57 EP |
1042 | mutex_lock(&newsbsec->lock); |
1043 | ||
1044 | newsbsec->flags = oldsbsec->flags; | |
1045 | ||
1046 | newsbsec->sid = oldsbsec->sid; | |
1047 | newsbsec->def_sid = oldsbsec->def_sid; | |
1048 | newsbsec->behavior = oldsbsec->behavior; | |
1049 | ||
0b4d3452 SM |
1050 | if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && |
1051 | !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { | |
aa8e712c | 1052 | rc = security_fs_use(&selinux_state, newsb); |
0b4d3452 SM |
1053 | if (rc) |
1054 | goto out; | |
1055 | } | |
1056 | ||
1057 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { | |
1058 | newsbsec->behavior = SECURITY_FS_USE_NATIVE; | |
1059 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
1060 | } | |
1061 | ||
c9180a57 EP |
1062 | if (set_context) { |
1063 | u32 sid = oldsbsec->mntpoint_sid; | |
1064 | ||
1065 | if (!set_fscontext) | |
1066 | newsbsec->sid = sid; | |
1067 | if (!set_rootcontext) { | |
83da53c5 | 1068 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); |
c9180a57 EP |
1069 | newisec->sid = sid; |
1070 | } | |
1071 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 1072 | } |
c9180a57 | 1073 | if (set_rootcontext) { |
83da53c5 AG |
1074 | const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); |
1075 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); | |
1da177e4 | 1076 | |
c9180a57 | 1077 | newisec->sid = oldisec->sid; |
1da177e4 LT |
1078 | } |
1079 | ||
c9180a57 | 1080 | sb_finish_set_opts(newsb); |
0b4d3452 | 1081 | out: |
c9180a57 | 1082 | mutex_unlock(&newsbsec->lock); |
0b4d3452 | 1083 | return rc; |
c9180a57 EP |
1084 | } |
1085 | ||
2e1479d9 AB |
1086 | static int selinux_parse_opts_str(char *options, |
1087 | struct security_mnt_opts *opts) | |
c9180a57 | 1088 | { |
e0007529 | 1089 | char *p; |
c9180a57 EP |
1090 | char *context = NULL, *defcontext = NULL; |
1091 | char *fscontext = NULL, *rootcontext = NULL; | |
e0007529 | 1092 | int rc, num_mnt_opts = 0; |
1da177e4 | 1093 | |
e0007529 | 1094 | opts->num_mnt_opts = 0; |
1da177e4 | 1095 | |
c9180a57 EP |
1096 | /* Standard string-based options. */ |
1097 | while ((p = strsep(&options, "|")) != NULL) { | |
1098 | int token; | |
1099 | substring_t args[MAX_OPT_ARGS]; | |
1da177e4 | 1100 | |
c9180a57 EP |
1101 | if (!*p) |
1102 | continue; | |
1da177e4 | 1103 | |
c9180a57 | 1104 | token = match_token(p, tokens, args); |
1da177e4 | 1105 | |
c9180a57 EP |
1106 | switch (token) { |
1107 | case Opt_context: | |
1108 | if (context || defcontext) { | |
1109 | rc = -EINVAL; | |
1110 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1111 | goto out_err; | |
1112 | } | |
1113 | context = match_strdup(&args[0]); | |
1114 | if (!context) { | |
1115 | rc = -ENOMEM; | |
1116 | goto out_err; | |
1117 | } | |
1118 | break; | |
1119 | ||
1120 | case Opt_fscontext: | |
1121 | if (fscontext) { | |
1122 | rc = -EINVAL; | |
1123 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1124 | goto out_err; | |
1125 | } | |
1126 | fscontext = match_strdup(&args[0]); | |
1127 | if (!fscontext) { | |
1128 | rc = -ENOMEM; | |
1129 | goto out_err; | |
1130 | } | |
1131 | break; | |
1132 | ||
1133 | case Opt_rootcontext: | |
1134 | if (rootcontext) { | |
1135 | rc = -EINVAL; | |
1136 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1137 | goto out_err; | |
1138 | } | |
1139 | rootcontext = match_strdup(&args[0]); | |
1140 | if (!rootcontext) { | |
1141 | rc = -ENOMEM; | |
1142 | goto out_err; | |
1143 | } | |
1144 | break; | |
1145 | ||
1146 | case Opt_defcontext: | |
1147 | if (context || defcontext) { | |
1148 | rc = -EINVAL; | |
1149 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1150 | goto out_err; | |
1151 | } | |
1152 | defcontext = match_strdup(&args[0]); | |
1153 | if (!defcontext) { | |
1154 | rc = -ENOMEM; | |
1155 | goto out_err; | |
1156 | } | |
1157 | break; | |
11689d47 DQ |
1158 | case Opt_labelsupport: |
1159 | break; | |
c9180a57 EP |
1160 | default: |
1161 | rc = -EINVAL; | |
1162 | printk(KERN_WARNING "SELinux: unknown mount option\n"); | |
1163 | goto out_err; | |
1da177e4 | 1164 | |
1da177e4 | 1165 | } |
1da177e4 | 1166 | } |
c9180a57 | 1167 | |
e0007529 | 1168 | rc = -ENOMEM; |
8931c3bd | 1169 | opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL); |
e0007529 EP |
1170 | if (!opts->mnt_opts) |
1171 | goto out_err; | |
1172 | ||
8931c3bd TH |
1173 | opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), |
1174 | GFP_KERNEL); | |
023f108d | 1175 | if (!opts->mnt_opts_flags) |
e0007529 | 1176 | goto out_err; |
e0007529 | 1177 | |
c9180a57 | 1178 | if (fscontext) { |
e0007529 EP |
1179 | opts->mnt_opts[num_mnt_opts] = fscontext; |
1180 | opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; | |
c9180a57 EP |
1181 | } |
1182 | if (context) { | |
e0007529 EP |
1183 | opts->mnt_opts[num_mnt_opts] = context; |
1184 | opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; | |
c9180a57 EP |
1185 | } |
1186 | if (rootcontext) { | |
e0007529 EP |
1187 | opts->mnt_opts[num_mnt_opts] = rootcontext; |
1188 | opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; | |
c9180a57 EP |
1189 | } |
1190 | if (defcontext) { | |
e0007529 EP |
1191 | opts->mnt_opts[num_mnt_opts] = defcontext; |
1192 | opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
1193 | } |
1194 | ||
e0007529 EP |
1195 | opts->num_mnt_opts = num_mnt_opts; |
1196 | return 0; | |
1197 | ||
c9180a57 | 1198 | out_err: |
023f108d | 1199 | security_free_mnt_opts(opts); |
c9180a57 EP |
1200 | kfree(context); |
1201 | kfree(defcontext); | |
1202 | kfree(fscontext); | |
1203 | kfree(rootcontext); | |
1da177e4 LT |
1204 | return rc; |
1205 | } | |
e0007529 EP |
1206 | /* |
1207 | * string mount options parsing and call set the sbsec | |
1208 | */ | |
1209 | static int superblock_doinit(struct super_block *sb, void *data) | |
1210 | { | |
1211 | int rc = 0; | |
1212 | char *options = data; | |
1213 | struct security_mnt_opts opts; | |
1214 | ||
1215 | security_init_mnt_opts(&opts); | |
1216 | ||
1217 | if (!data) | |
1218 | goto out; | |
1219 | ||
1220 | BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); | |
1221 | ||
1222 | rc = selinux_parse_opts_str(options, &opts); | |
1223 | if (rc) | |
1224 | goto out_err; | |
1225 | ||
1226 | out: | |
649f6e77 | 1227 | rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); |
e0007529 EP |
1228 | |
1229 | out_err: | |
1230 | security_free_mnt_opts(&opts); | |
1231 | return rc; | |
1232 | } | |
1da177e4 | 1233 | |
3583a711 AB |
1234 | static void selinux_write_opts(struct seq_file *m, |
1235 | struct security_mnt_opts *opts) | |
2069f457 EP |
1236 | { |
1237 | int i; | |
1238 | char *prefix; | |
1239 | ||
1240 | for (i = 0; i < opts->num_mnt_opts; i++) { | |
11689d47 DQ |
1241 | char *has_comma; |
1242 | ||
1243 | if (opts->mnt_opts[i]) | |
1244 | has_comma = strchr(opts->mnt_opts[i], ','); | |
1245 | else | |
1246 | has_comma = NULL; | |
2069f457 EP |
1247 | |
1248 | switch (opts->mnt_opts_flags[i]) { | |
1249 | case CONTEXT_MNT: | |
1250 | prefix = CONTEXT_STR; | |
1251 | break; | |
1252 | case FSCONTEXT_MNT: | |
1253 | prefix = FSCONTEXT_STR; | |
1254 | break; | |
1255 | case ROOTCONTEXT_MNT: | |
1256 | prefix = ROOTCONTEXT_STR; | |
1257 | break; | |
1258 | case DEFCONTEXT_MNT: | |
1259 | prefix = DEFCONTEXT_STR; | |
1260 | break; | |
12f348b9 | 1261 | case SBLABEL_MNT: |
11689d47 DQ |
1262 | seq_putc(m, ','); |
1263 | seq_puts(m, LABELSUPP_STR); | |
1264 | continue; | |
2069f457 EP |
1265 | default: |
1266 | BUG(); | |
a35c6c83 | 1267 | return; |
2069f457 EP |
1268 | }; |
1269 | /* we need a comma before each option */ | |
1270 | seq_putc(m, ','); | |
1271 | seq_puts(m, prefix); | |
1272 | if (has_comma) | |
1273 | seq_putc(m, '\"'); | |
a068acf2 | 1274 | seq_escape(m, opts->mnt_opts[i], "\"\n\\"); |
2069f457 EP |
1275 | if (has_comma) |
1276 | seq_putc(m, '\"'); | |
1277 | } | |
1278 | } | |
1279 | ||
1280 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1281 | { | |
1282 | struct security_mnt_opts opts; | |
1283 | int rc; | |
1284 | ||
1285 | rc = selinux_get_mnt_opts(sb, &opts); | |
383795c2 EP |
1286 | if (rc) { |
1287 | /* before policy load we may get EINVAL, don't show anything */ | |
1288 | if (rc == -EINVAL) | |
1289 | rc = 0; | |
2069f457 | 1290 | return rc; |
383795c2 | 1291 | } |
2069f457 EP |
1292 | |
1293 | selinux_write_opts(m, &opts); | |
1294 | ||
1295 | security_free_mnt_opts(&opts); | |
1296 | ||
1297 | return rc; | |
1298 | } | |
1299 | ||
1da177e4 LT |
1300 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1301 | { | |
1302 | switch (mode & S_IFMT) { | |
1303 | case S_IFSOCK: | |
1304 | return SECCLASS_SOCK_FILE; | |
1305 | case S_IFLNK: | |
1306 | return SECCLASS_LNK_FILE; | |
1307 | case S_IFREG: | |
1308 | return SECCLASS_FILE; | |
1309 | case S_IFBLK: | |
1310 | return SECCLASS_BLK_FILE; | |
1311 | case S_IFDIR: | |
1312 | return SECCLASS_DIR; | |
1313 | case S_IFCHR: | |
1314 | return SECCLASS_CHR_FILE; | |
1315 | case S_IFIFO: | |
1316 | return SECCLASS_FIFO_FILE; | |
1317 | ||
1318 | } | |
1319 | ||
1320 | return SECCLASS_FILE; | |
1321 | } | |
1322 | ||
13402580 JM |
1323 | static inline int default_protocol_stream(int protocol) |
1324 | { | |
1325 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1326 | } | |
1327 | ||
1328 | static inline int default_protocol_dgram(int protocol) | |
1329 | { | |
1330 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1331 | } | |
1332 | ||
1da177e4 LT |
1333 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1334 | { | |
aa8e712c | 1335 | int extsockclass = selinux_policycap_extsockclass(); |
da69a530 | 1336 | |
1da177e4 LT |
1337 | switch (family) { |
1338 | case PF_UNIX: | |
1339 | switch (type) { | |
1340 | case SOCK_STREAM: | |
1341 | case SOCK_SEQPACKET: | |
1342 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1343 | case SOCK_DGRAM: | |
2a764b52 | 1344 | case SOCK_RAW: |
1da177e4 LT |
1345 | return SECCLASS_UNIX_DGRAM_SOCKET; |
1346 | } | |
1347 | break; | |
1348 | case PF_INET: | |
1349 | case PF_INET6: | |
1350 | switch (type) { | |
1351 | case SOCK_STREAM: | |
da69a530 | 1352 | case SOCK_SEQPACKET: |
13402580 JM |
1353 | if (default_protocol_stream(protocol)) |
1354 | return SECCLASS_TCP_SOCKET; | |
da69a530 SS |
1355 | else if (extsockclass && protocol == IPPROTO_SCTP) |
1356 | return SECCLASS_SCTP_SOCKET; | |
13402580 JM |
1357 | else |
1358 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1359 | case SOCK_DGRAM: |
13402580 JM |
1360 | if (default_protocol_dgram(protocol)) |
1361 | return SECCLASS_UDP_SOCKET; | |
ef37979a SS |
1362 | else if (extsockclass && (protocol == IPPROTO_ICMP || |
1363 | protocol == IPPROTO_ICMPV6)) | |
da69a530 | 1364 | return SECCLASS_ICMP_SOCKET; |
13402580 JM |
1365 | else |
1366 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1367 | case SOCK_DCCP: |
1368 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1369 | default: |
1da177e4 LT |
1370 | return SECCLASS_RAWIP_SOCKET; |
1371 | } | |
1372 | break; | |
1373 | case PF_NETLINK: | |
1374 | switch (protocol) { | |
1375 | case NETLINK_ROUTE: | |
1376 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
7f1fb60c | 1377 | case NETLINK_SOCK_DIAG: |
1da177e4 LT |
1378 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1379 | case NETLINK_NFLOG: | |
1380 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1381 | case NETLINK_XFRM: | |
1382 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1383 | case NETLINK_SELINUX: | |
1384 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
6c6d2e9b SS |
1385 | case NETLINK_ISCSI: |
1386 | return SECCLASS_NETLINK_ISCSI_SOCKET; | |
1da177e4 LT |
1387 | case NETLINK_AUDIT: |
1388 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
6c6d2e9b SS |
1389 | case NETLINK_FIB_LOOKUP: |
1390 | return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; | |
1391 | case NETLINK_CONNECTOR: | |
1392 | return SECCLASS_NETLINK_CONNECTOR_SOCKET; | |
1393 | case NETLINK_NETFILTER: | |
1394 | return SECCLASS_NETLINK_NETFILTER_SOCKET; | |
1da177e4 LT |
1395 | case NETLINK_DNRTMSG: |
1396 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1397 | case NETLINK_KOBJECT_UEVENT: |
1398 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
6c6d2e9b SS |
1399 | case NETLINK_GENERIC: |
1400 | return SECCLASS_NETLINK_GENERIC_SOCKET; | |
1401 | case NETLINK_SCSITRANSPORT: | |
1402 | return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; | |
1403 | case NETLINK_RDMA: | |
1404 | return SECCLASS_NETLINK_RDMA_SOCKET; | |
1405 | case NETLINK_CRYPTO: | |
1406 | return SECCLASS_NETLINK_CRYPTO_SOCKET; | |
1da177e4 LT |
1407 | default: |
1408 | return SECCLASS_NETLINK_SOCKET; | |
1409 | } | |
1410 | case PF_PACKET: | |
1411 | return SECCLASS_PACKET_SOCKET; | |
1412 | case PF_KEY: | |
1413 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1414 | case PF_APPLETALK: |
1415 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1416 | } |
1417 | ||
da69a530 SS |
1418 | if (extsockclass) { |
1419 | switch (family) { | |
1420 | case PF_AX25: | |
1421 | return SECCLASS_AX25_SOCKET; | |
1422 | case PF_IPX: | |
1423 | return SECCLASS_IPX_SOCKET; | |
1424 | case PF_NETROM: | |
1425 | return SECCLASS_NETROM_SOCKET; | |
da69a530 SS |
1426 | case PF_ATMPVC: |
1427 | return SECCLASS_ATMPVC_SOCKET; | |
1428 | case PF_X25: | |
1429 | return SECCLASS_X25_SOCKET; | |
1430 | case PF_ROSE: | |
1431 | return SECCLASS_ROSE_SOCKET; | |
1432 | case PF_DECnet: | |
1433 | return SECCLASS_DECNET_SOCKET; | |
1434 | case PF_ATMSVC: | |
1435 | return SECCLASS_ATMSVC_SOCKET; | |
1436 | case PF_RDS: | |
1437 | return SECCLASS_RDS_SOCKET; | |
1438 | case PF_IRDA: | |
1439 | return SECCLASS_IRDA_SOCKET; | |
1440 | case PF_PPPOX: | |
1441 | return SECCLASS_PPPOX_SOCKET; | |
1442 | case PF_LLC: | |
1443 | return SECCLASS_LLC_SOCKET; | |
da69a530 SS |
1444 | case PF_CAN: |
1445 | return SECCLASS_CAN_SOCKET; | |
1446 | case PF_TIPC: | |
1447 | return SECCLASS_TIPC_SOCKET; | |
1448 | case PF_BLUETOOTH: | |
1449 | return SECCLASS_BLUETOOTH_SOCKET; | |
1450 | case PF_IUCV: | |
1451 | return SECCLASS_IUCV_SOCKET; | |
1452 | case PF_RXRPC: | |
1453 | return SECCLASS_RXRPC_SOCKET; | |
1454 | case PF_ISDN: | |
1455 | return SECCLASS_ISDN_SOCKET; | |
1456 | case PF_PHONET: | |
1457 | return SECCLASS_PHONET_SOCKET; | |
1458 | case PF_IEEE802154: | |
1459 | return SECCLASS_IEEE802154_SOCKET; | |
1460 | case PF_CAIF: | |
1461 | return SECCLASS_CAIF_SOCKET; | |
1462 | case PF_ALG: | |
1463 | return SECCLASS_ALG_SOCKET; | |
1464 | case PF_NFC: | |
1465 | return SECCLASS_NFC_SOCKET; | |
1466 | case PF_VSOCK: | |
1467 | return SECCLASS_VSOCK_SOCKET; | |
1468 | case PF_KCM: | |
1469 | return SECCLASS_KCM_SOCKET; | |
1470 | case PF_QIPCRTR: | |
1471 | return SECCLASS_QIPCRTR_SOCKET; | |
3051bf36 LT |
1472 | case PF_SMC: |
1473 | return SECCLASS_SMC_SOCKET; | |
1474 | #if PF_MAX > 44 | |
da69a530 SS |
1475 | #error New address family defined, please update this function. |
1476 | #endif | |
1477 | } | |
1478 | } | |
1479 | ||
1da177e4 LT |
1480 | return SECCLASS_SOCKET; |
1481 | } | |
1482 | ||
134509d5 SS |
1483 | static int selinux_genfs_get_sid(struct dentry *dentry, |
1484 | u16 tclass, | |
1485 | u16 flags, | |
1486 | u32 *sid) | |
1da177e4 | 1487 | { |
8e6c9693 | 1488 | int rc; |
fc64005c | 1489 | struct super_block *sb = dentry->d_sb; |
8e6c9693 | 1490 | char *buffer, *path; |
1da177e4 | 1491 | |
828dfe1d | 1492 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1493 | if (!buffer) |
1494 | return -ENOMEM; | |
1495 | ||
8e6c9693 LAG |
1496 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1497 | if (IS_ERR(path)) | |
1498 | rc = PTR_ERR(path); | |
1499 | else { | |
134509d5 SS |
1500 | if (flags & SE_SBPROC) { |
1501 | /* each process gets a /proc/PID/ entry. Strip off the | |
1502 | * PID part to get a valid selinux labeling. | |
1503 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1504 | while (path[1] >= '0' && path[1] <= '9') { | |
1505 | path[1] = '/'; | |
1506 | path++; | |
1507 | } | |
8e6c9693 | 1508 | } |
aa8e712c SS |
1509 | rc = security_genfs_sid(&selinux_state, sb->s_type->name, |
1510 | path, tclass, sid); | |
1da177e4 | 1511 | } |
1da177e4 LT |
1512 | free_page((unsigned long)buffer); |
1513 | return rc; | |
1514 | } | |
1da177e4 LT |
1515 | |
1516 | /* The inode's security attributes must be initialized before first use. */ | |
1517 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1518 | { | |
1519 | struct superblock_security_struct *sbsec = NULL; | |
1520 | struct inode_security_struct *isec = inode->i_security; | |
9287aed2 AG |
1521 | u32 task_sid, sid = 0; |
1522 | u16 sclass; | |
1da177e4 LT |
1523 | struct dentry *dentry; |
1524 | #define INITCONTEXTLEN 255 | |
1525 | char *context = NULL; | |
1526 | unsigned len = 0; | |
1527 | int rc = 0; | |
1da177e4 | 1528 | |
6f3be9f5 | 1529 | if (isec->initialized == LABEL_INITIALIZED) |
13457d07 | 1530 | return 0; |
1da177e4 | 1531 | |
9287aed2 | 1532 | spin_lock(&isec->lock); |
6f3be9f5 | 1533 | if (isec->initialized == LABEL_INITIALIZED) |
23970741 | 1534 | goto out_unlock; |
1da177e4 | 1535 | |
13457d07 AG |
1536 | if (isec->sclass == SECCLASS_FILE) |
1537 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1538 | ||
1da177e4 | 1539 | sbsec = inode->i_sb->s_security; |
0d90a7ec | 1540 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1541 | /* Defer initialization until selinux_complete_init, |
1542 | after the initial policy is loaded and the security | |
1543 | server is ready to handle calls. */ | |
1544 | spin_lock(&sbsec->isec_lock); | |
1545 | if (list_empty(&isec->list)) | |
1546 | list_add(&isec->list, &sbsec->isec_head); | |
1547 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1548 | goto out_unlock; |
1da177e4 LT |
1549 | } |
1550 | ||
9287aed2 AG |
1551 | sclass = isec->sclass; |
1552 | task_sid = isec->task_sid; | |
1553 | sid = isec->sid; | |
1554 | isec->initialized = LABEL_PENDING; | |
1555 | spin_unlock(&isec->lock); | |
1556 | ||
1da177e4 | 1557 | switch (sbsec->behavior) { |
eb9ae686 DQ |
1558 | case SECURITY_FS_USE_NATIVE: |
1559 | break; | |
1da177e4 | 1560 | case SECURITY_FS_USE_XATTR: |
5d6c3191 | 1561 | if (!(inode->i_opflags & IOP_XATTR)) { |
9287aed2 | 1562 | sid = sbsec->def_sid; |
1da177e4 LT |
1563 | break; |
1564 | } | |
1da177e4 LT |
1565 | /* Need a dentry, since the xattr API requires one. |
1566 | Life would be simpler if we could just pass the inode. */ | |
1567 | if (opt_dentry) { | |
1568 | /* Called from d_instantiate or d_splice_alias. */ | |
1569 | dentry = dget(opt_dentry); | |
1570 | } else { | |
1571 | /* Called from selinux_complete_init, try to find a dentry. */ | |
1572 | dentry = d_find_alias(inode); | |
1573 | } | |
1574 | if (!dentry) { | |
df7f54c0 EP |
1575 | /* |
1576 | * this is can be hit on boot when a file is accessed | |
1577 | * before the policy is loaded. When we load policy we | |
1578 | * may find inodes that have no dentry on the | |
1579 | * sbsec->isec_head list. No reason to complain as these | |
1580 | * will get fixed up the next time we go through | |
1581 | * inode_doinit with a dentry, before these inodes could | |
1582 | * be used again by userspace. | |
1583 | */ | |
9287aed2 | 1584 | goto out; |
1da177e4 LT |
1585 | } |
1586 | ||
1587 | len = INITCONTEXTLEN; | |
4cb912f1 | 1588 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1589 | if (!context) { |
1590 | rc = -ENOMEM; | |
1591 | dput(dentry); | |
9287aed2 | 1592 | goto out; |
1da177e4 | 1593 | } |
4cb912f1 | 1594 | context[len] = '\0'; |
5d6c3191 | 1595 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); |
1da177e4 | 1596 | if (rc == -ERANGE) { |
314dabb8 JM |
1597 | kfree(context); |
1598 | ||
1da177e4 | 1599 | /* Need a larger buffer. Query for the right size. */ |
5d6c3191 | 1600 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); |
1da177e4 LT |
1601 | if (rc < 0) { |
1602 | dput(dentry); | |
9287aed2 | 1603 | goto out; |
1da177e4 | 1604 | } |
1da177e4 | 1605 | len = rc; |
4cb912f1 | 1606 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1607 | if (!context) { |
1608 | rc = -ENOMEM; | |
1609 | dput(dentry); | |
9287aed2 | 1610 | goto out; |
1da177e4 | 1611 | } |
4cb912f1 | 1612 | context[len] = '\0'; |
5d6c3191 | 1613 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); |
1da177e4 LT |
1614 | } |
1615 | dput(dentry); | |
1616 | if (rc < 0) { | |
1617 | if (rc != -ENODATA) { | |
744ba35e | 1618 | printk(KERN_WARNING "SELinux: %s: getxattr returned " |
dd6f953a | 1619 | "%d for dev=%s ino=%ld\n", __func__, |
1da177e4 LT |
1620 | -rc, inode->i_sb->s_id, inode->i_ino); |
1621 | kfree(context); | |
9287aed2 | 1622 | goto out; |
1da177e4 LT |
1623 | } |
1624 | /* Map ENODATA to the default file SID */ | |
1625 | sid = sbsec->def_sid; | |
1626 | rc = 0; | |
1627 | } else { | |
aa8e712c SS |
1628 | rc = security_context_to_sid_default(&selinux_state, |
1629 | context, rc, &sid, | |
869ab514 SS |
1630 | sbsec->def_sid, |
1631 | GFP_NOFS); | |
1da177e4 | 1632 | if (rc) { |
4ba0a8ad EP |
1633 | char *dev = inode->i_sb->s_id; |
1634 | unsigned long ino = inode->i_ino; | |
1635 | ||
1636 | if (rc == -EINVAL) { | |
1637 | if (printk_ratelimit()) | |
1638 | printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " | |
1639 | "context=%s. This indicates you may need to relabel the inode or the " | |
1640 | "filesystem in question.\n", ino, dev, context); | |
1641 | } else { | |
1642 | printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " | |
1643 | "returned %d for dev=%s ino=%ld\n", | |
1644 | __func__, context, -rc, dev, ino); | |
1645 | } | |
1da177e4 LT |
1646 | kfree(context); |
1647 | /* Leave with the unlabeled SID */ | |
1648 | rc = 0; | |
1649 | break; | |
1650 | } | |
1651 | } | |
1652 | kfree(context); | |
1da177e4 LT |
1653 | break; |
1654 | case SECURITY_FS_USE_TASK: | |
9287aed2 | 1655 | sid = task_sid; |
1da177e4 LT |
1656 | break; |
1657 | case SECURITY_FS_USE_TRANS: | |
1658 | /* Default to the fs SID. */ | |
9287aed2 | 1659 | sid = sbsec->sid; |
1da177e4 LT |
1660 | |
1661 | /* Try to obtain a transition SID. */ | |
aa8e712c SS |
1662 | rc = security_transition_sid(&selinux_state, task_sid, sid, |
1663 | sclass, NULL, &sid); | |
1da177e4 | 1664 | if (rc) |
9287aed2 | 1665 | goto out; |
1da177e4 | 1666 | break; |
c312feb2 | 1667 | case SECURITY_FS_USE_MNTPOINT: |
9287aed2 | 1668 | sid = sbsec->mntpoint_sid; |
c312feb2 | 1669 | break; |
1da177e4 | 1670 | default: |
c312feb2 | 1671 | /* Default to the fs superblock SID. */ |
9287aed2 | 1672 | sid = sbsec->sid; |
1da177e4 | 1673 | |
134509d5 | 1674 | if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) { |
f64410ec PM |
1675 | /* We must have a dentry to determine the label on |
1676 | * procfs inodes */ | |
1677 | if (opt_dentry) | |
1678 | /* Called from d_instantiate or | |
1679 | * d_splice_alias. */ | |
1680 | dentry = dget(opt_dentry); | |
1681 | else | |
1682 | /* Called from selinux_complete_init, try to | |
1683 | * find a dentry. */ | |
1684 | dentry = d_find_alias(inode); | |
1685 | /* | |
1686 | * This can be hit on boot when a file is accessed | |
1687 | * before the policy is loaded. When we load policy we | |
1688 | * may find inodes that have no dentry on the | |
1689 | * sbsec->isec_head list. No reason to complain as | |
1690 | * these will get fixed up the next time we go through | |
1691 | * inode_doinit() with a dentry, before these inodes | |
1692 | * could be used again by userspace. | |
1693 | */ | |
1694 | if (!dentry) | |
9287aed2 AG |
1695 | goto out; |
1696 | rc = selinux_genfs_get_sid(dentry, sclass, | |
134509d5 | 1697 | sbsec->flags, &sid); |
f64410ec PM |
1698 | dput(dentry); |
1699 | if (rc) | |
9287aed2 | 1700 | goto out; |
1da177e4 LT |
1701 | } |
1702 | break; | |
1703 | } | |
1704 | ||
9287aed2 AG |
1705 | out: |
1706 | spin_lock(&isec->lock); | |
1707 | if (isec->initialized == LABEL_PENDING) { | |
1708 | if (!sid || rc) { | |
1709 | isec->initialized = LABEL_INVALID; | |
1710 | goto out_unlock; | |
1711 | } | |
1712 | ||
1713 | isec->initialized = LABEL_INITIALIZED; | |
1714 | isec->sid = sid; | |
1715 | } | |
1da177e4 | 1716 | |
23970741 | 1717 | out_unlock: |
9287aed2 | 1718 | spin_unlock(&isec->lock); |
1da177e4 LT |
1719 | return rc; |
1720 | } | |
1721 | ||
1722 | /* Convert a Linux signal to an access vector. */ | |
1723 | static inline u32 signal_to_av(int sig) | |
1724 | { | |
1725 | u32 perm = 0; | |
1726 | ||
1727 | switch (sig) { | |
1728 | case SIGCHLD: | |
1729 | /* Commonly granted from child to parent. */ | |
1730 | perm = PROCESS__SIGCHLD; | |
1731 | break; | |
1732 | case SIGKILL: | |
1733 | /* Cannot be caught or ignored */ | |
1734 | perm = PROCESS__SIGKILL; | |
1735 | break; | |
1736 | case SIGSTOP: | |
1737 | /* Cannot be caught or ignored */ | |
1738 | perm = PROCESS__SIGSTOP; | |
1739 | break; | |
1740 | default: | |
1741 | /* All other signals. */ | |
1742 | perm = PROCESS__SIGNAL; | |
1743 | break; | |
1744 | } | |
1745 | ||
1746 | return perm; | |
1747 | } | |
1748 | ||
b68e418c SS |
1749 | #if CAP_LAST_CAP > 63 |
1750 | #error Fix SELinux to handle capabilities > 63. | |
1751 | #endif | |
1752 | ||
1da177e4 | 1753 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1754 | static int cred_has_capability(const struct cred *cred, |
8e4ff6f2 | 1755 | int cap, int audit, bool initns) |
1da177e4 | 1756 | { |
2bf49690 | 1757 | struct common_audit_data ad; |
06112163 | 1758 | struct av_decision avd; |
b68e418c | 1759 | u16 sclass; |
3699c53c | 1760 | u32 sid = cred_sid(cred); |
b68e418c | 1761 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1762 | int rc; |
1da177e4 | 1763 | |
50c205f5 | 1764 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1765 | ad.u.cap = cap; |
1766 | ||
b68e418c SS |
1767 | switch (CAP_TO_INDEX(cap)) { |
1768 | case 0: | |
8e4ff6f2 | 1769 | sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; |
b68e418c SS |
1770 | break; |
1771 | case 1: | |
8e4ff6f2 | 1772 | sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; |
b68e418c SS |
1773 | break; |
1774 | default: | |
1775 | printk(KERN_ERR | |
1776 | "SELinux: out of range capability %d\n", cap); | |
1777 | BUG(); | |
a35c6c83 | 1778 | return -EINVAL; |
b68e418c | 1779 | } |
06112163 | 1780 | |
6b6bc620 SS |
1781 | rc = avc_has_perm_noaudit(&selinux_state, |
1782 | sid, sid, sclass, av, 0, &avd); | |
9ade0cf4 | 1783 | if (audit == SECURITY_CAP_AUDIT) { |
6b6bc620 SS |
1784 | int rc2 = avc_audit(&selinux_state, |
1785 | sid, sid, sclass, av, &avd, rc, &ad, 0); | |
9ade0cf4 EP |
1786 | if (rc2) |
1787 | return rc2; | |
1788 | } | |
06112163 | 1789 | return rc; |
1da177e4 LT |
1790 | } |
1791 | ||
1da177e4 LT |
1792 | /* Check whether a task has a particular permission to an inode. |
1793 | The 'adp' parameter is optional and allows other audit | |
1794 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1795 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1796 | struct inode *inode, |
1797 | u32 perms, | |
19e49834 | 1798 | struct common_audit_data *adp) |
1da177e4 | 1799 | { |
1da177e4 | 1800 | struct inode_security_struct *isec; |
275bb41e | 1801 | u32 sid; |
1da177e4 | 1802 | |
e0e81739 DH |
1803 | validate_creds(cred); |
1804 | ||
828dfe1d | 1805 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1806 | return 0; |
1807 | ||
88e67f3b | 1808 | sid = cred_sid(cred); |
1da177e4 LT |
1809 | isec = inode->i_security; |
1810 | ||
6b6bc620 SS |
1811 | return avc_has_perm(&selinux_state, |
1812 | sid, isec->sid, isec->sclass, perms, adp); | |
1da177e4 LT |
1813 | } |
1814 | ||
1815 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1816 | the dentry to help the auditing code to more easily generate the | |
1817 | pathname if needed. */ | |
88e67f3b | 1818 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1819 | struct dentry *dentry, |
1820 | u32 av) | |
1821 | { | |
c6f493d6 | 1822 | struct inode *inode = d_backing_inode(dentry); |
2bf49690 | 1823 | struct common_audit_data ad; |
88e67f3b | 1824 | |
50c205f5 | 1825 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1826 | ad.u.dentry = dentry; |
5d226df4 | 1827 | __inode_security_revalidate(inode, dentry, true); |
19e49834 | 1828 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1829 | } |
1830 | ||
1831 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1832 | the path to help the auditing code to more easily generate the | |
1833 | pathname if needed. */ | |
1834 | static inline int path_has_perm(const struct cred *cred, | |
3f7036a0 | 1835 | const struct path *path, |
2875fa00 EP |
1836 | u32 av) |
1837 | { | |
c6f493d6 | 1838 | struct inode *inode = d_backing_inode(path->dentry); |
2875fa00 EP |
1839 | struct common_audit_data ad; |
1840 | ||
50c205f5 | 1841 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1842 | ad.u.path = *path; |
5d226df4 | 1843 | __inode_security_revalidate(inode, path->dentry, true); |
19e49834 | 1844 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1845 | } |
1846 | ||
13f8e981 DH |
1847 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1848 | static inline int file_path_has_perm(const struct cred *cred, | |
1849 | struct file *file, | |
1850 | u32 av) | |
1851 | { | |
1852 | struct common_audit_data ad; | |
1853 | ||
43af5de7 VG |
1854 | ad.type = LSM_AUDIT_DATA_FILE; |
1855 | ad.u.file = file; | |
19e49834 | 1856 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1857 | } |
1858 | ||
f66e448c CF |
1859 | #ifdef CONFIG_BPF_SYSCALL |
1860 | static int bpf_fd_pass(struct file *file, u32 sid); | |
1861 | #endif | |
1862 | ||
1da177e4 LT |
1863 | /* Check whether a task can use an open file descriptor to |
1864 | access an inode in a given way. Check access to the | |
1865 | descriptor itself, and then use dentry_has_perm to | |
1866 | check a particular permission to the file. | |
1867 | Access to the descriptor is implicitly granted if it | |
1868 | has the same SID as the process. If av is zero, then | |
1869 | access to the file is not checked, e.g. for cases | |
1870 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1871 | static int file_has_perm(const struct cred *cred, |
1872 | struct file *file, | |
1873 | u32 av) | |
1da177e4 | 1874 | { |
1da177e4 | 1875 | struct file_security_struct *fsec = file->f_security; |
496ad9aa | 1876 | struct inode *inode = file_inode(file); |
2bf49690 | 1877 | struct common_audit_data ad; |
88e67f3b | 1878 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1879 | int rc; |
1880 | ||
43af5de7 VG |
1881 | ad.type = LSM_AUDIT_DATA_FILE; |
1882 | ad.u.file = file; | |
1da177e4 | 1883 | |
275bb41e | 1884 | if (sid != fsec->sid) { |
6b6bc620 SS |
1885 | rc = avc_has_perm(&selinux_state, |
1886 | sid, fsec->sid, | |
1da177e4 LT |
1887 | SECCLASS_FD, |
1888 | FD__USE, | |
1889 | &ad); | |
1890 | if (rc) | |
88e67f3b | 1891 | goto out; |
1da177e4 LT |
1892 | } |
1893 | ||
f66e448c CF |
1894 | #ifdef CONFIG_BPF_SYSCALL |
1895 | rc = bpf_fd_pass(file, cred_sid(cred)); | |
1896 | if (rc) | |
1897 | return rc; | |
1898 | #endif | |
1899 | ||
1da177e4 | 1900 | /* av is zero if only checking access to the descriptor. */ |
88e67f3b | 1901 | rc = 0; |
1da177e4 | 1902 | if (av) |
19e49834 | 1903 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1904 | |
88e67f3b DH |
1905 | out: |
1906 | return rc; | |
1da177e4 LT |
1907 | } |
1908 | ||
c3c188b2 DH |
1909 | /* |
1910 | * Determine the label for an inode that might be unioned. | |
1911 | */ | |
c957f6df VG |
1912 | static int |
1913 | selinux_determine_inode_label(const struct task_security_struct *tsec, | |
1914 | struct inode *dir, | |
1915 | const struct qstr *name, u16 tclass, | |
1916 | u32 *_new_isid) | |
c3c188b2 DH |
1917 | { |
1918 | const struct superblock_security_struct *sbsec = dir->i_sb->s_security; | |
c3c188b2 DH |
1919 | |
1920 | if ((sbsec->flags & SE_SBINITIALIZED) && | |
1921 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { | |
1922 | *_new_isid = sbsec->mntpoint_sid; | |
1923 | } else if ((sbsec->flags & SBLABEL_MNT) && | |
1924 | tsec->create_sid) { | |
1925 | *_new_isid = tsec->create_sid; | |
1926 | } else { | |
20cdef8d | 1927 | const struct inode_security_struct *dsec = inode_security(dir); |
aa8e712c SS |
1928 | return security_transition_sid(&selinux_state, tsec->sid, |
1929 | dsec->sid, tclass, | |
c3c188b2 DH |
1930 | name, _new_isid); |
1931 | } | |
1932 | ||
1933 | return 0; | |
1934 | } | |
1935 | ||
1da177e4 LT |
1936 | /* Check whether a task can create a file. */ |
1937 | static int may_create(struct inode *dir, | |
1938 | struct dentry *dentry, | |
1939 | u16 tclass) | |
1940 | { | |
5fb49870 | 1941 | const struct task_security_struct *tsec = current_security(); |
1da177e4 LT |
1942 | struct inode_security_struct *dsec; |
1943 | struct superblock_security_struct *sbsec; | |
275bb41e | 1944 | u32 sid, newsid; |
2bf49690 | 1945 | struct common_audit_data ad; |
1da177e4 LT |
1946 | int rc; |
1947 | ||
83da53c5 | 1948 | dsec = inode_security(dir); |
1da177e4 LT |
1949 | sbsec = dir->i_sb->s_security; |
1950 | ||
275bb41e | 1951 | sid = tsec->sid; |
275bb41e | 1952 | |
50c205f5 | 1953 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1954 | ad.u.dentry = dentry; |
1da177e4 | 1955 | |
6b6bc620 SS |
1956 | rc = avc_has_perm(&selinux_state, |
1957 | sid, dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
1958 | DIR__ADD_NAME | DIR__SEARCH, |
1959 | &ad); | |
1960 | if (rc) | |
1961 | return rc; | |
1962 | ||
c957f6df VG |
1963 | rc = selinux_determine_inode_label(current_security(), dir, |
1964 | &dentry->d_name, tclass, &newsid); | |
c3c188b2 DH |
1965 | if (rc) |
1966 | return rc; | |
1da177e4 | 1967 | |
6b6bc620 SS |
1968 | rc = avc_has_perm(&selinux_state, |
1969 | sid, newsid, tclass, FILE__CREATE, &ad); | |
1da177e4 LT |
1970 | if (rc) |
1971 | return rc; | |
1972 | ||
6b6bc620 SS |
1973 | return avc_has_perm(&selinux_state, |
1974 | newsid, sbsec->sid, | |
1da177e4 LT |
1975 | SECCLASS_FILESYSTEM, |
1976 | FILESYSTEM__ASSOCIATE, &ad); | |
1977 | } | |
1978 | ||
828dfe1d EP |
1979 | #define MAY_LINK 0 |
1980 | #define MAY_UNLINK 1 | |
1981 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1982 | |
1983 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1984 | static int may_link(struct inode *dir, | |
1985 | struct dentry *dentry, | |
1986 | int kind) | |
1987 | ||
1988 | { | |
1da177e4 | 1989 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 1990 | struct common_audit_data ad; |
275bb41e | 1991 | u32 sid = current_sid(); |
1da177e4 LT |
1992 | u32 av; |
1993 | int rc; | |
1994 | ||
83da53c5 AG |
1995 | dsec = inode_security(dir); |
1996 | isec = backing_inode_security(dentry); | |
1da177e4 | 1997 | |
50c205f5 | 1998 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1999 | ad.u.dentry = dentry; |
1da177e4 LT |
2000 | |
2001 | av = DIR__SEARCH; | |
2002 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
6b6bc620 SS |
2003 | rc = avc_has_perm(&selinux_state, |
2004 | sid, dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
2005 | if (rc) |
2006 | return rc; | |
2007 | ||
2008 | switch (kind) { | |
2009 | case MAY_LINK: | |
2010 | av = FILE__LINK; | |
2011 | break; | |
2012 | case MAY_UNLINK: | |
2013 | av = FILE__UNLINK; | |
2014 | break; | |
2015 | case MAY_RMDIR: | |
2016 | av = DIR__RMDIR; | |
2017 | break; | |
2018 | default: | |
744ba35e EP |
2019 | printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", |
2020 | __func__, kind); | |
1da177e4 LT |
2021 | return 0; |
2022 | } | |
2023 | ||
6b6bc620 SS |
2024 | rc = avc_has_perm(&selinux_state, |
2025 | sid, isec->sid, isec->sclass, av, &ad); | |
1da177e4 LT |
2026 | return rc; |
2027 | } | |
2028 | ||
2029 | static inline int may_rename(struct inode *old_dir, | |
2030 | struct dentry *old_dentry, | |
2031 | struct inode *new_dir, | |
2032 | struct dentry *new_dentry) | |
2033 | { | |
1da177e4 | 2034 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 2035 | struct common_audit_data ad; |
275bb41e | 2036 | u32 sid = current_sid(); |
1da177e4 LT |
2037 | u32 av; |
2038 | int old_is_dir, new_is_dir; | |
2039 | int rc; | |
2040 | ||
83da53c5 AG |
2041 | old_dsec = inode_security(old_dir); |
2042 | old_isec = backing_inode_security(old_dentry); | |
e36cb0b8 | 2043 | old_is_dir = d_is_dir(old_dentry); |
83da53c5 | 2044 | new_dsec = inode_security(new_dir); |
1da177e4 | 2045 | |
50c205f5 | 2046 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 2047 | |
a269434d | 2048 | ad.u.dentry = old_dentry; |
6b6bc620 SS |
2049 | rc = avc_has_perm(&selinux_state, |
2050 | sid, old_dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
2051 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
2052 | if (rc) | |
2053 | return rc; | |
6b6bc620 SS |
2054 | rc = avc_has_perm(&selinux_state, |
2055 | sid, old_isec->sid, | |
1da177e4 LT |
2056 | old_isec->sclass, FILE__RENAME, &ad); |
2057 | if (rc) | |
2058 | return rc; | |
2059 | if (old_is_dir && new_dir != old_dir) { | |
6b6bc620 SS |
2060 | rc = avc_has_perm(&selinux_state, |
2061 | sid, old_isec->sid, | |
1da177e4 LT |
2062 | old_isec->sclass, DIR__REPARENT, &ad); |
2063 | if (rc) | |
2064 | return rc; | |
2065 | } | |
2066 | ||
a269434d | 2067 | ad.u.dentry = new_dentry; |
1da177e4 | 2068 | av = DIR__ADD_NAME | DIR__SEARCH; |
2c616d4d | 2069 | if (d_is_positive(new_dentry)) |
1da177e4 | 2070 | av |= DIR__REMOVE_NAME; |
6b6bc620 SS |
2071 | rc = avc_has_perm(&selinux_state, |
2072 | sid, new_dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
2073 | if (rc) |
2074 | return rc; | |
2c616d4d | 2075 | if (d_is_positive(new_dentry)) { |
83da53c5 | 2076 | new_isec = backing_inode_security(new_dentry); |
e36cb0b8 | 2077 | new_is_dir = d_is_dir(new_dentry); |
6b6bc620 SS |
2078 | rc = avc_has_perm(&selinux_state, |
2079 | sid, new_isec->sid, | |
1da177e4 LT |
2080 | new_isec->sclass, |
2081 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
2082 | if (rc) | |
2083 | return rc; | |
2084 | } | |
2085 | ||
2086 | return 0; | |
2087 | } | |
2088 | ||
2089 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 2090 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
2091 | struct super_block *sb, |
2092 | u32 perms, | |
2bf49690 | 2093 | struct common_audit_data *ad) |
1da177e4 | 2094 | { |
1da177e4 | 2095 | struct superblock_security_struct *sbsec; |
88e67f3b | 2096 | u32 sid = cred_sid(cred); |
1da177e4 | 2097 | |
1da177e4 | 2098 | sbsec = sb->s_security; |
6b6bc620 SS |
2099 | return avc_has_perm(&selinux_state, |
2100 | sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); | |
1da177e4 LT |
2101 | } |
2102 | ||
2103 | /* Convert a Linux mode and permission mask to an access vector. */ | |
2104 | static inline u32 file_mask_to_av(int mode, int mask) | |
2105 | { | |
2106 | u32 av = 0; | |
2107 | ||
dba19c60 | 2108 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
2109 | if (mask & MAY_EXEC) |
2110 | av |= FILE__EXECUTE; | |
2111 | if (mask & MAY_READ) | |
2112 | av |= FILE__READ; | |
2113 | ||
2114 | if (mask & MAY_APPEND) | |
2115 | av |= FILE__APPEND; | |
2116 | else if (mask & MAY_WRITE) | |
2117 | av |= FILE__WRITE; | |
2118 | ||
2119 | } else { | |
2120 | if (mask & MAY_EXEC) | |
2121 | av |= DIR__SEARCH; | |
2122 | if (mask & MAY_WRITE) | |
2123 | av |= DIR__WRITE; | |
2124 | if (mask & MAY_READ) | |
2125 | av |= DIR__READ; | |
2126 | } | |
2127 | ||
2128 | return av; | |
2129 | } | |
2130 | ||
8b6a5a37 EP |
2131 | /* Convert a Linux file to an access vector. */ |
2132 | static inline u32 file_to_av(struct file *file) | |
2133 | { | |
2134 | u32 av = 0; | |
2135 | ||
2136 | if (file->f_mode & FMODE_READ) | |
2137 | av |= FILE__READ; | |
2138 | if (file->f_mode & FMODE_WRITE) { | |
2139 | if (file->f_flags & O_APPEND) | |
2140 | av |= FILE__APPEND; | |
2141 | else | |
2142 | av |= FILE__WRITE; | |
2143 | } | |
2144 | if (!av) { | |
2145 | /* | |
2146 | * Special file opened with flags 3 for ioctl-only use. | |
2147 | */ | |
2148 | av = FILE__IOCTL; | |
2149 | } | |
2150 | ||
2151 | return av; | |
2152 | } | |
2153 | ||
b0c636b9 | 2154 | /* |
8b6a5a37 | 2155 | * Convert a file to an access vector and include the correct open |
b0c636b9 EP |
2156 | * open permission. |
2157 | */ | |
8b6a5a37 | 2158 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 2159 | { |
8b6a5a37 | 2160 | u32 av = file_to_av(file); |
ccb54478 | 2161 | struct inode *inode = file_inode(file); |
b0c636b9 | 2162 | |
aa8e712c SS |
2163 | if (selinux_policycap_openperm() && |
2164 | inode->i_sb->s_magic != SOCKFS_MAGIC) | |
49b7b8de EP |
2165 | av |= FILE__OPEN; |
2166 | ||
b0c636b9 EP |
2167 | return av; |
2168 | } | |
2169 | ||
1da177e4 LT |
2170 | /* Hook functions begin here. */ |
2171 | ||
79af7307 SS |
2172 | static int selinux_binder_set_context_mgr(struct task_struct *mgr) |
2173 | { | |
2174 | u32 mysid = current_sid(); | |
2175 | u32 mgrsid = task_sid(mgr); | |
2176 | ||
6b6bc620 SS |
2177 | return avc_has_perm(&selinux_state, |
2178 | mysid, mgrsid, SECCLASS_BINDER, | |
79af7307 SS |
2179 | BINDER__SET_CONTEXT_MGR, NULL); |
2180 | } | |
2181 | ||
2182 | static int selinux_binder_transaction(struct task_struct *from, | |
2183 | struct task_struct *to) | |
2184 | { | |
2185 | u32 mysid = current_sid(); | |
2186 | u32 fromsid = task_sid(from); | |
2187 | u32 tosid = task_sid(to); | |
2188 | int rc; | |
2189 | ||
2190 | if (mysid != fromsid) { | |
6b6bc620 SS |
2191 | rc = avc_has_perm(&selinux_state, |
2192 | mysid, fromsid, SECCLASS_BINDER, | |
79af7307 SS |
2193 | BINDER__IMPERSONATE, NULL); |
2194 | if (rc) | |
2195 | return rc; | |
2196 | } | |
2197 | ||
6b6bc620 SS |
2198 | return avc_has_perm(&selinux_state, |
2199 | fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, | |
79af7307 SS |
2200 | NULL); |
2201 | } | |
2202 | ||
2203 | static int selinux_binder_transfer_binder(struct task_struct *from, | |
2204 | struct task_struct *to) | |
2205 | { | |
2206 | u32 fromsid = task_sid(from); | |
2207 | u32 tosid = task_sid(to); | |
2208 | ||
6b6bc620 SS |
2209 | return avc_has_perm(&selinux_state, |
2210 | fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, | |
79af7307 SS |
2211 | NULL); |
2212 | } | |
2213 | ||
2214 | static int selinux_binder_transfer_file(struct task_struct *from, | |
2215 | struct task_struct *to, | |
2216 | struct file *file) | |
2217 | { | |
2218 | u32 sid = task_sid(to); | |
2219 | struct file_security_struct *fsec = file->f_security; | |
83da53c5 | 2220 | struct dentry *dentry = file->f_path.dentry; |
20cdef8d | 2221 | struct inode_security_struct *isec; |
79af7307 SS |
2222 | struct common_audit_data ad; |
2223 | int rc; | |
2224 | ||
2225 | ad.type = LSM_AUDIT_DATA_PATH; | |
2226 | ad.u.path = file->f_path; | |
2227 | ||
2228 | if (sid != fsec->sid) { | |
6b6bc620 SS |
2229 | rc = avc_has_perm(&selinux_state, |
2230 | sid, fsec->sid, | |
79af7307 SS |
2231 | SECCLASS_FD, |
2232 | FD__USE, | |
2233 | &ad); | |
2234 | if (rc) | |
2235 | return rc; | |
2236 | } | |
2237 | ||
f66e448c CF |
2238 | #ifdef CONFIG_BPF_SYSCALL |
2239 | rc = bpf_fd_pass(file, sid); | |
2240 | if (rc) | |
2241 | return rc; | |
2242 | #endif | |
2243 | ||
83da53c5 | 2244 | if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
79af7307 SS |
2245 | return 0; |
2246 | ||
20cdef8d | 2247 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
2248 | return avc_has_perm(&selinux_state, |
2249 | sid, isec->sid, isec->sclass, file_to_av(file), | |
79af7307 SS |
2250 | &ad); |
2251 | } | |
2252 | ||
9e48858f | 2253 | static int selinux_ptrace_access_check(struct task_struct *child, |
5cd9c58f | 2254 | unsigned int mode) |
1da177e4 | 2255 | { |
be0554c9 SS |
2256 | u32 sid = current_sid(); |
2257 | u32 csid = task_sid(child); | |
2258 | ||
2259 | if (mode & PTRACE_MODE_READ) | |
6b6bc620 SS |
2260 | return avc_has_perm(&selinux_state, |
2261 | sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 | 2262 | |
6b6bc620 SS |
2263 | return avc_has_perm(&selinux_state, |
2264 | sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); | |
5cd9c58f DH |
2265 | } |
2266 | ||
2267 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
2268 | { | |
6b6bc620 SS |
2269 | return avc_has_perm(&selinux_state, |
2270 | task_sid(parent), current_sid(), SECCLASS_PROCESS, | |
be0554c9 | 2271 | PROCESS__PTRACE, NULL); |
1da177e4 LT |
2272 | } |
2273 | ||
2274 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 2275 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 | 2276 | { |
6b6bc620 SS |
2277 | return avc_has_perm(&selinux_state, |
2278 | current_sid(), task_sid(target), SECCLASS_PROCESS, | |
be0554c9 | 2279 | PROCESS__GETCAP, NULL); |
1da177e4 LT |
2280 | } |
2281 | ||
d84f4f99 DH |
2282 | static int selinux_capset(struct cred *new, const struct cred *old, |
2283 | const kernel_cap_t *effective, | |
2284 | const kernel_cap_t *inheritable, | |
2285 | const kernel_cap_t *permitted) | |
1da177e4 | 2286 | { |
6b6bc620 SS |
2287 | return avc_has_perm(&selinux_state, |
2288 | cred_sid(old), cred_sid(new), SECCLASS_PROCESS, | |
be0554c9 | 2289 | PROCESS__SETCAP, NULL); |
1da177e4 LT |
2290 | } |
2291 | ||
5626d3e8 JM |
2292 | /* |
2293 | * (This comment used to live with the selinux_task_setuid hook, | |
2294 | * which was removed). | |
2295 | * | |
2296 | * Since setuid only affects the current process, and since the SELinux | |
2297 | * controls are not based on the Linux identity attributes, SELinux does not | |
2298 | * need to control this operation. However, SELinux does control the use of | |
2299 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
2300 | */ | |
2301 | ||
6a9de491 EP |
2302 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
2303 | int cap, int audit) | |
1da177e4 | 2304 | { |
8e4ff6f2 | 2305 | return cred_has_capability(cred, cap, audit, ns == &init_user_ns); |
1da177e4 LT |
2306 | } |
2307 | ||
1da177e4 LT |
2308 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
2309 | { | |
88e67f3b | 2310 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2311 | int rc = 0; |
2312 | ||
2313 | if (!sb) | |
2314 | return 0; | |
2315 | ||
2316 | switch (cmds) { | |
828dfe1d EP |
2317 | case Q_SYNC: |
2318 | case Q_QUOTAON: | |
2319 | case Q_QUOTAOFF: | |
2320 | case Q_SETINFO: | |
2321 | case Q_SETQUOTA: | |
88e67f3b | 2322 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
2323 | break; |
2324 | case Q_GETFMT: | |
2325 | case Q_GETINFO: | |
2326 | case Q_GETQUOTA: | |
88e67f3b | 2327 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
2328 | break; |
2329 | default: | |
2330 | rc = 0; /* let the kernel handle invalid cmds */ | |
2331 | break; | |
1da177e4 LT |
2332 | } |
2333 | return rc; | |
2334 | } | |
2335 | ||
2336 | static int selinux_quota_on(struct dentry *dentry) | |
2337 | { | |
88e67f3b DH |
2338 | const struct cred *cred = current_cred(); |
2339 | ||
2875fa00 | 2340 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
2341 | } |
2342 | ||
12b3052c | 2343 | static int selinux_syslog(int type) |
1da177e4 | 2344 | { |
1da177e4 | 2345 | switch (type) { |
d78ca3cd KC |
2346 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2347 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
6b6bc620 SS |
2348 | return avc_has_perm(&selinux_state, |
2349 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2350 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); |
d78ca3cd KC |
2351 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2352 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2353 | /* Set level of messages printed to console */ | |
2354 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
6b6bc620 SS |
2355 | return avc_has_perm(&selinux_state, |
2356 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 SS |
2357 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, |
2358 | NULL); | |
1da177e4 | 2359 | } |
be0554c9 | 2360 | /* All other syslog types */ |
6b6bc620 SS |
2361 | return avc_has_perm(&selinux_state, |
2362 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2363 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); |
1da177e4 LT |
2364 | } |
2365 | ||
2366 | /* | |
2367 | * Check that a process has enough memory to allocate a new virtual | |
2368 | * mapping. 0 means there is enough memory for the allocation to | |
2369 | * succeed and -ENOMEM implies there is not. | |
2370 | * | |
1da177e4 LT |
2371 | * Do not audit the selinux permission check, as this is applied to all |
2372 | * processes that allocate mappings. | |
2373 | */ | |
34b4e4aa | 2374 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2375 | { |
2376 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2377 | |
b1d9e6b0 | 2378 | rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, |
8e4ff6f2 | 2379 | SECURITY_CAP_NOAUDIT, true); |
1da177e4 LT |
2380 | if (rc == 0) |
2381 | cap_sys_admin = 1; | |
2382 | ||
b1d9e6b0 | 2383 | return cap_sys_admin; |
1da177e4 LT |
2384 | } |
2385 | ||
2386 | /* binprm security operations */ | |
2387 | ||
be0554c9 | 2388 | static u32 ptrace_parent_sid(void) |
0c6181cb PM |
2389 | { |
2390 | u32 sid = 0; | |
2391 | struct task_struct *tracer; | |
2392 | ||
2393 | rcu_read_lock(); | |
be0554c9 | 2394 | tracer = ptrace_parent(current); |
0c6181cb PM |
2395 | if (tracer) |
2396 | sid = task_sid(tracer); | |
2397 | rcu_read_unlock(); | |
2398 | ||
2399 | return sid; | |
2400 | } | |
2401 | ||
7b0d0b40 SS |
2402 | static int check_nnp_nosuid(const struct linux_binprm *bprm, |
2403 | const struct task_security_struct *old_tsec, | |
2404 | const struct task_security_struct *new_tsec) | |
2405 | { | |
2406 | int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); | |
380cf5ba | 2407 | int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); |
7b0d0b40 | 2408 | int rc; |
af63f419 | 2409 | u32 av; |
7b0d0b40 SS |
2410 | |
2411 | if (!nnp && !nosuid) | |
2412 | return 0; /* neither NNP nor nosuid */ | |
2413 | ||
2414 | if (new_tsec->sid == old_tsec->sid) | |
2415 | return 0; /* No change in credentials */ | |
2416 | ||
2417 | /* | |
af63f419 SS |
2418 | * If the policy enables the nnp_nosuid_transition policy capability, |
2419 | * then we permit transitions under NNP or nosuid if the | |
2420 | * policy allows the corresponding permission between | |
2421 | * the old and new contexts. | |
7b0d0b40 | 2422 | */ |
aa8e712c | 2423 | if (selinux_policycap_nnp_nosuid_transition()) { |
af63f419 | 2424 | av = 0; |
7b0d0b40 | 2425 | if (nnp) |
af63f419 SS |
2426 | av |= PROCESS2__NNP_TRANSITION; |
2427 | if (nosuid) | |
2428 | av |= PROCESS2__NOSUID_TRANSITION; | |
6b6bc620 SS |
2429 | rc = avc_has_perm(&selinux_state, |
2430 | old_tsec->sid, new_tsec->sid, | |
af63f419 SS |
2431 | SECCLASS_PROCESS2, av, NULL); |
2432 | if (!rc) | |
2433 | return 0; | |
7b0d0b40 | 2434 | } |
af63f419 SS |
2435 | |
2436 | /* | |
2437 | * We also permit NNP or nosuid transitions to bounded SIDs, | |
2438 | * i.e. SIDs that are guaranteed to only be allowed a subset | |
2439 | * of the permissions of the current SID. | |
2440 | */ | |
aa8e712c SS |
2441 | rc = security_bounded_transition(&selinux_state, old_tsec->sid, |
2442 | new_tsec->sid); | |
af63f419 SS |
2443 | if (!rc) |
2444 | return 0; | |
2445 | ||
2446 | /* | |
2447 | * On failure, preserve the errno values for NNP vs nosuid. | |
2448 | * NNP: Operation not permitted for caller. | |
2449 | * nosuid: Permission denied to file. | |
2450 | */ | |
2451 | if (nnp) | |
2452 | return -EPERM; | |
2453 | return -EACCES; | |
7b0d0b40 SS |
2454 | } |
2455 | ||
a6f76f23 | 2456 | static int selinux_bprm_set_creds(struct linux_binprm *bprm) |
1da177e4 | 2457 | { |
a6f76f23 DH |
2458 | const struct task_security_struct *old_tsec; |
2459 | struct task_security_struct *new_tsec; | |
1da177e4 | 2460 | struct inode_security_struct *isec; |
2bf49690 | 2461 | struct common_audit_data ad; |
496ad9aa | 2462 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2463 | int rc; |
2464 | ||
a6f76f23 DH |
2465 | /* SELinux context only depends on initial program or script and not |
2466 | * the script interpreter */ | |
ddb4a144 | 2467 | if (bprm->called_set_creds) |
1da177e4 LT |
2468 | return 0; |
2469 | ||
a6f76f23 DH |
2470 | old_tsec = current_security(); |
2471 | new_tsec = bprm->cred->security; | |
83da53c5 | 2472 | isec = inode_security(inode); |
1da177e4 LT |
2473 | |
2474 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2475 | new_tsec->sid = old_tsec->sid; |
2476 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2477 | |
28eba5bf | 2478 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2479 | new_tsec->create_sid = 0; |
2480 | new_tsec->keycreate_sid = 0; | |
2481 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2482 | |
a6f76f23 DH |
2483 | if (old_tsec->exec_sid) { |
2484 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2485 | /* Reset exec SID on execve. */ |
a6f76f23 | 2486 | new_tsec->exec_sid = 0; |
259e5e6c | 2487 | |
7b0d0b40 SS |
2488 | /* Fail on NNP or nosuid if not an allowed transition. */ |
2489 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2490 | if (rc) | |
2491 | return rc; | |
1da177e4 LT |
2492 | } else { |
2493 | /* Check for a default transition on this program. */ | |
aa8e712c SS |
2494 | rc = security_transition_sid(&selinux_state, old_tsec->sid, |
2495 | isec->sid, SECCLASS_PROCESS, NULL, | |
652bb9b0 | 2496 | &new_tsec->sid); |
1da177e4 LT |
2497 | if (rc) |
2498 | return rc; | |
7b0d0b40 SS |
2499 | |
2500 | /* | |
2501 | * Fallback to old SID on NNP or nosuid if not an allowed | |
2502 | * transition. | |
2503 | */ | |
2504 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2505 | if (rc) | |
2506 | new_tsec->sid = old_tsec->sid; | |
1da177e4 LT |
2507 | } |
2508 | ||
43af5de7 VG |
2509 | ad.type = LSM_AUDIT_DATA_FILE; |
2510 | ad.u.file = bprm->file; | |
1da177e4 | 2511 | |
a6f76f23 | 2512 | if (new_tsec->sid == old_tsec->sid) { |
6b6bc620 SS |
2513 | rc = avc_has_perm(&selinux_state, |
2514 | old_tsec->sid, isec->sid, | |
1da177e4 LT |
2515 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2516 | if (rc) | |
2517 | return rc; | |
2518 | } else { | |
2519 | /* Check permissions for the transition. */ | |
6b6bc620 SS |
2520 | rc = avc_has_perm(&selinux_state, |
2521 | old_tsec->sid, new_tsec->sid, | |
1da177e4 LT |
2522 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2523 | if (rc) | |
2524 | return rc; | |
2525 | ||
6b6bc620 SS |
2526 | rc = avc_has_perm(&selinux_state, |
2527 | new_tsec->sid, isec->sid, | |
1da177e4 LT |
2528 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2529 | if (rc) | |
2530 | return rc; | |
2531 | ||
a6f76f23 DH |
2532 | /* Check for shared state */ |
2533 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
6b6bc620 SS |
2534 | rc = avc_has_perm(&selinux_state, |
2535 | old_tsec->sid, new_tsec->sid, | |
a6f76f23 DH |
2536 | SECCLASS_PROCESS, PROCESS__SHARE, |
2537 | NULL); | |
2538 | if (rc) | |
2539 | return -EPERM; | |
2540 | } | |
2541 | ||
2542 | /* Make sure that anyone attempting to ptrace over a task that | |
2543 | * changes its SID has the appropriate permit */ | |
9227dd2a | 2544 | if (bprm->unsafe & LSM_UNSAFE_PTRACE) { |
be0554c9 | 2545 | u32 ptsid = ptrace_parent_sid(); |
a6f76f23 | 2546 | if (ptsid != 0) { |
6b6bc620 SS |
2547 | rc = avc_has_perm(&selinux_state, |
2548 | ptsid, new_tsec->sid, | |
a6f76f23 DH |
2549 | SECCLASS_PROCESS, |
2550 | PROCESS__PTRACE, NULL); | |
2551 | if (rc) | |
2552 | return -EPERM; | |
2553 | } | |
2554 | } | |
1da177e4 | 2555 | |
a6f76f23 DH |
2556 | /* Clear any possibly unsafe personality bits on exec: */ |
2557 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
275bb41e | 2558 | |
1da177e4 LT |
2559 | /* Enable secure mode for SIDs transitions unless |
2560 | the noatsecure permission is granted between | |
2561 | the two SIDs, i.e. ahp returns 0. */ | |
6b6bc620 SS |
2562 | rc = avc_has_perm(&selinux_state, |
2563 | old_tsec->sid, new_tsec->sid, | |
62874c3a KC |
2564 | SECCLASS_PROCESS, PROCESS__NOATSECURE, |
2565 | NULL); | |
2566 | bprm->secureexec |= !!rc; | |
1da177e4 LT |
2567 | } |
2568 | ||
62874c3a | 2569 | return 0; |
1da177e4 LT |
2570 | } |
2571 | ||
c3c073f8 AV |
2572 | static int match_file(const void *p, struct file *file, unsigned fd) |
2573 | { | |
2574 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2575 | } | |
2576 | ||
1da177e4 | 2577 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2578 | static inline void flush_unauthorized_files(const struct cred *cred, |
2579 | struct files_struct *files) | |
1da177e4 | 2580 | { |
1da177e4 | 2581 | struct file *file, *devnull = NULL; |
b20c8122 | 2582 | struct tty_struct *tty; |
24ec839c | 2583 | int drop_tty = 0; |
c3c073f8 | 2584 | unsigned n; |
1da177e4 | 2585 | |
24ec839c | 2586 | tty = get_current_tty(); |
1da177e4 | 2587 | if (tty) { |
4a510969 | 2588 | spin_lock(&tty->files_lock); |
37dd0bd0 | 2589 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2590 | struct tty_file_private *file_priv; |
37dd0bd0 | 2591 | |
1da177e4 | 2592 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2593 | Use file_path_has_perm on the tty path directly |
2594 | rather than using file_has_perm, as this particular | |
2595 | open file may belong to another process and we are | |
2596 | only interested in the inode-based check here. */ | |
d996b62a NP |
2597 | file_priv = list_first_entry(&tty->tty_files, |
2598 | struct tty_file_private, list); | |
2599 | file = file_priv->file; | |
13f8e981 | 2600 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2601 | drop_tty = 1; |
1da177e4 | 2602 | } |
4a510969 | 2603 | spin_unlock(&tty->files_lock); |
452a00d2 | 2604 | tty_kref_put(tty); |
1da177e4 | 2605 | } |
98a27ba4 EB |
2606 | /* Reset controlling tty. */ |
2607 | if (drop_tty) | |
2608 | no_tty(); | |
1da177e4 LT |
2609 | |
2610 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2611 | n = iterate_fd(files, 0, match_file, cred); |
2612 | if (!n) /* none found? */ | |
2613 | return; | |
1da177e4 | 2614 | |
c3c073f8 | 2615 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2616 | if (IS_ERR(devnull)) |
2617 | devnull = NULL; | |
2618 | /* replace all the matching ones with this */ | |
2619 | do { | |
2620 | replace_fd(n - 1, devnull, 0); | |
2621 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2622 | if (devnull) | |
c3c073f8 | 2623 | fput(devnull); |
1da177e4 LT |
2624 | } |
2625 | ||
a6f76f23 DH |
2626 | /* |
2627 | * Prepare a process for imminent new credential changes due to exec | |
2628 | */ | |
2629 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2630 | { |
a6f76f23 DH |
2631 | struct task_security_struct *new_tsec; |
2632 | struct rlimit *rlim, *initrlim; | |
2633 | int rc, i; | |
d84f4f99 | 2634 | |
a6f76f23 DH |
2635 | new_tsec = bprm->cred->security; |
2636 | if (new_tsec->sid == new_tsec->osid) | |
2637 | return; | |
1da177e4 | 2638 | |
a6f76f23 DH |
2639 | /* Close files for which the new task SID is not authorized. */ |
2640 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2641 | |
a6f76f23 DH |
2642 | /* Always clear parent death signal on SID transitions. */ |
2643 | current->pdeath_signal = 0; | |
0356357c | 2644 | |
a6f76f23 DH |
2645 | /* Check whether the new SID can inherit resource limits from the old |
2646 | * SID. If not, reset all soft limits to the lower of the current | |
2647 | * task's hard limit and the init task's soft limit. | |
2648 | * | |
2649 | * Note that the setting of hard limits (even to lower them) can be | |
2650 | * controlled by the setrlimit check. The inclusion of the init task's | |
2651 | * soft limit into the computation is to avoid resetting soft limits | |
2652 | * higher than the default soft limit for cases where the default is | |
2653 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2654 | */ | |
6b6bc620 SS |
2655 | rc = avc_has_perm(&selinux_state, |
2656 | new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
a6f76f23 DH |
2657 | PROCESS__RLIMITINH, NULL); |
2658 | if (rc) { | |
eb2d55a3 ON |
2659 | /* protect against do_prlimit() */ |
2660 | task_lock(current); | |
a6f76f23 DH |
2661 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2662 | rlim = current->signal->rlim + i; | |
2663 | initrlim = init_task.signal->rlim + i; | |
2664 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2665 | } |
eb2d55a3 | 2666 | task_unlock(current); |
baa73d9e NP |
2667 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) |
2668 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2669 | } |
2670 | } | |
2671 | ||
2672 | /* | |
a6f76f23 DH |
2673 | * Clean up the process immediately after the installation of new credentials |
2674 | * due to exec | |
1da177e4 | 2675 | */ |
a6f76f23 | 2676 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2677 | { |
a6f76f23 | 2678 | const struct task_security_struct *tsec = current_security(); |
1da177e4 | 2679 | struct itimerval itimer; |
a6f76f23 | 2680 | u32 osid, sid; |
1da177e4 LT |
2681 | int rc, i; |
2682 | ||
a6f76f23 DH |
2683 | osid = tsec->osid; |
2684 | sid = tsec->sid; | |
2685 | ||
2686 | if (sid == osid) | |
1da177e4 LT |
2687 | return; |
2688 | ||
a6f76f23 DH |
2689 | /* Check whether the new SID can inherit signal state from the old SID. |
2690 | * If not, clear itimers to avoid subsequent signal generation and | |
2691 | * flush and unblock signals. | |
2692 | * | |
2693 | * This must occur _after_ the task SID has been updated so that any | |
2694 | * kill done after the flush will be checked against the new SID. | |
2695 | */ | |
6b6bc620 SS |
2696 | rc = avc_has_perm(&selinux_state, |
2697 | osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 | 2698 | if (rc) { |
baa73d9e NP |
2699 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) { |
2700 | memset(&itimer, 0, sizeof itimer); | |
2701 | for (i = 0; i < 3; i++) | |
2702 | do_setitimer(i, &itimer, NULL); | |
2703 | } | |
1da177e4 | 2704 | spin_lock_irq(¤t->sighand->siglock); |
9e7c8f8c ON |
2705 | if (!fatal_signal_pending(current)) { |
2706 | flush_sigqueue(¤t->pending); | |
2707 | flush_sigqueue(¤t->signal->shared_pending); | |
3bcac026 DH |
2708 | flush_signal_handlers(current, 1); |
2709 | sigemptyset(¤t->blocked); | |
9e7c8f8c | 2710 | recalc_sigpending(); |
3bcac026 | 2711 | } |
1da177e4 LT |
2712 | spin_unlock_irq(¤t->sighand->siglock); |
2713 | } | |
2714 | ||
a6f76f23 DH |
2715 | /* Wake up the parent if it is waiting so that it can recheck |
2716 | * wait permission to the new task SID. */ | |
ecd6de3c | 2717 | read_lock(&tasklist_lock); |
0b7570e7 | 2718 | __wake_up_parent(current, current->real_parent); |
ecd6de3c | 2719 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2720 | } |
2721 | ||
2722 | /* superblock security operations */ | |
2723 | ||
2724 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2725 | { | |
2726 | return superblock_alloc_security(sb); | |
2727 | } | |
2728 | ||
2729 | static void selinux_sb_free_security(struct super_block *sb) | |
2730 | { | |
2731 | superblock_free_security(sb); | |
2732 | } | |
2733 | ||
2734 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2735 | { | |
2736 | if (plen > olen) | |
2737 | return 0; | |
2738 | ||
2739 | return !memcmp(prefix, option, plen); | |
2740 | } | |
2741 | ||
2742 | static inline int selinux_option(char *option, int len) | |
2743 | { | |
832cbd9a EP |
2744 | return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || |
2745 | match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || | |
2746 | match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || | |
11689d47 DQ |
2747 | match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || |
2748 | match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); | |
1da177e4 LT |
2749 | } |
2750 | ||
2751 | static inline void take_option(char **to, char *from, int *first, int len) | |
2752 | { | |
2753 | if (!*first) { | |
2754 | **to = ','; | |
2755 | *to += 1; | |
3528a953 | 2756 | } else |
1da177e4 LT |
2757 | *first = 0; |
2758 | memcpy(*to, from, len); | |
2759 | *to += len; | |
2760 | } | |
2761 | ||
828dfe1d EP |
2762 | static inline void take_selinux_option(char **to, char *from, int *first, |
2763 | int len) | |
3528a953 CO |
2764 | { |
2765 | int current_size = 0; | |
2766 | ||
2767 | if (!*first) { | |
2768 | **to = '|'; | |
2769 | *to += 1; | |
828dfe1d | 2770 | } else |
3528a953 CO |
2771 | *first = 0; |
2772 | ||
2773 | while (current_size < len) { | |
2774 | if (*from != '"') { | |
2775 | **to = *from; | |
2776 | *to += 1; | |
2777 | } | |
2778 | from += 1; | |
2779 | current_size += 1; | |
2780 | } | |
2781 | } | |
2782 | ||
e0007529 | 2783 | static int selinux_sb_copy_data(char *orig, char *copy) |
1da177e4 LT |
2784 | { |
2785 | int fnosec, fsec, rc = 0; | |
2786 | char *in_save, *in_curr, *in_end; | |
2787 | char *sec_curr, *nosec_save, *nosec; | |
3528a953 | 2788 | int open_quote = 0; |
1da177e4 LT |
2789 | |
2790 | in_curr = orig; | |
2791 | sec_curr = copy; | |
2792 | ||
1da177e4 LT |
2793 | nosec = (char *)get_zeroed_page(GFP_KERNEL); |
2794 | if (!nosec) { | |
2795 | rc = -ENOMEM; | |
2796 | goto out; | |
2797 | } | |
2798 | ||
2799 | nosec_save = nosec; | |
2800 | fnosec = fsec = 1; | |
2801 | in_save = in_end = orig; | |
2802 | ||
2803 | do { | |
3528a953 CO |
2804 | if (*in_end == '"') |
2805 | open_quote = !open_quote; | |
2806 | if ((*in_end == ',' && open_quote == 0) || | |
2807 | *in_end == '\0') { | |
1da177e4 LT |
2808 | int len = in_end - in_curr; |
2809 | ||
2810 | if (selinux_option(in_curr, len)) | |
3528a953 | 2811 | take_selinux_option(&sec_curr, in_curr, &fsec, len); |
1da177e4 LT |
2812 | else |
2813 | take_option(&nosec, in_curr, &fnosec, len); | |
2814 | ||
2815 | in_curr = in_end + 1; | |
2816 | } | |
2817 | } while (*in_end++); | |
2818 | ||
6931dfc9 | 2819 | strcpy(in_save, nosec_save); |
da3caa20 | 2820 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
2821 | out: |
2822 | return rc; | |
2823 | } | |
2824 | ||
026eb167 EP |
2825 | static int selinux_sb_remount(struct super_block *sb, void *data) |
2826 | { | |
2827 | int rc, i, *flags; | |
2828 | struct security_mnt_opts opts; | |
2829 | char *secdata, **mount_options; | |
2830 | struct superblock_security_struct *sbsec = sb->s_security; | |
2831 | ||
2832 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2833 | return 0; | |
2834 | ||
2835 | if (!data) | |
2836 | return 0; | |
2837 | ||
2838 | if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) | |
2839 | return 0; | |
2840 | ||
2841 | security_init_mnt_opts(&opts); | |
2842 | secdata = alloc_secdata(); | |
2843 | if (!secdata) | |
2844 | return -ENOMEM; | |
2845 | rc = selinux_sb_copy_data(data, secdata); | |
2846 | if (rc) | |
2847 | goto out_free_secdata; | |
2848 | ||
2849 | rc = selinux_parse_opts_str(secdata, &opts); | |
2850 | if (rc) | |
2851 | goto out_free_secdata; | |
2852 | ||
2853 | mount_options = opts.mnt_opts; | |
2854 | flags = opts.mnt_opts_flags; | |
2855 | ||
2856 | for (i = 0; i < opts.num_mnt_opts; i++) { | |
2857 | u32 sid; | |
026eb167 | 2858 | |
12f348b9 | 2859 | if (flags[i] == SBLABEL_MNT) |
026eb167 | 2860 | continue; |
aa8e712c SS |
2861 | rc = security_context_str_to_sid(&selinux_state, |
2862 | mount_options[i], &sid, | |
2863 | GFP_KERNEL); | |
026eb167 | 2864 | if (rc) { |
44be2f65 | 2865 | printk(KERN_WARNING "SELinux: security_context_str_to_sid" |
29b1deb2 LT |
2866 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
2867 | mount_options[i], sb->s_id, sb->s_type->name, rc); | |
026eb167 EP |
2868 | goto out_free_opts; |
2869 | } | |
2870 | rc = -EINVAL; | |
2871 | switch (flags[i]) { | |
2872 | case FSCONTEXT_MNT: | |
2873 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) | |
2874 | goto out_bad_option; | |
2875 | break; | |
2876 | case CONTEXT_MNT: | |
2877 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2878 | goto out_bad_option; | |
2879 | break; | |
2880 | case ROOTCONTEXT_MNT: { | |
2881 | struct inode_security_struct *root_isec; | |
83da53c5 | 2882 | root_isec = backing_inode_security(sb->s_root); |
026eb167 EP |
2883 | |
2884 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2885 | goto out_bad_option; | |
2886 | break; | |
2887 | } | |
2888 | case DEFCONTEXT_MNT: | |
2889 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2890 | goto out_bad_option; | |
2891 | break; | |
2892 | default: | |
2893 | goto out_free_opts; | |
2894 | } | |
2895 | } | |
2896 | ||
2897 | rc = 0; | |
2898 | out_free_opts: | |
2899 | security_free_mnt_opts(&opts); | |
2900 | out_free_secdata: | |
2901 | free_secdata(secdata); | |
2902 | return rc; | |
2903 | out_bad_option: | |
2904 | printk(KERN_WARNING "SELinux: unable to change security options " | |
29b1deb2 LT |
2905 | "during remount (dev %s, type=%s)\n", sb->s_id, |
2906 | sb->s_type->name); | |
026eb167 EP |
2907 | goto out_free_opts; |
2908 | } | |
2909 | ||
12204e24 | 2910 | static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) |
1da177e4 | 2911 | { |
88e67f3b | 2912 | const struct cred *cred = current_cred(); |
2bf49690 | 2913 | struct common_audit_data ad; |
1da177e4 LT |
2914 | int rc; |
2915 | ||
2916 | rc = superblock_doinit(sb, data); | |
2917 | if (rc) | |
2918 | return rc; | |
2919 | ||
74192246 JM |
2920 | /* Allow all mounts performed by the kernel */ |
2921 | if (flags & MS_KERNMOUNT) | |
2922 | return 0; | |
2923 | ||
50c205f5 | 2924 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2925 | ad.u.dentry = sb->s_root; |
88e67f3b | 2926 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2927 | } |
2928 | ||
726c3342 | 2929 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2930 | { |
88e67f3b | 2931 | const struct cred *cred = current_cred(); |
2bf49690 | 2932 | struct common_audit_data ad; |
1da177e4 | 2933 | |
50c205f5 | 2934 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2935 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2936 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2937 | } |
2938 | ||
808d4e3c | 2939 | static int selinux_mount(const char *dev_name, |
8a04c43b | 2940 | const struct path *path, |
808d4e3c | 2941 | const char *type, |
828dfe1d EP |
2942 | unsigned long flags, |
2943 | void *data) | |
1da177e4 | 2944 | { |
88e67f3b | 2945 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2946 | |
2947 | if (flags & MS_REMOUNT) | |
d8c9584e | 2948 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2949 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2950 | else |
2875fa00 | 2951 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2952 | } |
2953 | ||
2954 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2955 | { | |
88e67f3b | 2956 | const struct cred *cred = current_cred(); |
1da177e4 | 2957 | |
88e67f3b | 2958 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2959 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2960 | } |
2961 | ||
2962 | /* inode security operations */ | |
2963 | ||
2964 | static int selinux_inode_alloc_security(struct inode *inode) | |
2965 | { | |
2966 | return inode_alloc_security(inode); | |
2967 | } | |
2968 | ||
2969 | static void selinux_inode_free_security(struct inode *inode) | |
2970 | { | |
2971 | inode_free_security(inode); | |
2972 | } | |
2973 | ||
d47be3df | 2974 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
4f3ccd76 | 2975 | const struct qstr *name, void **ctx, |
d47be3df DQ |
2976 | u32 *ctxlen) |
2977 | { | |
d47be3df DQ |
2978 | u32 newsid; |
2979 | int rc; | |
2980 | ||
c957f6df VG |
2981 | rc = selinux_determine_inode_label(current_security(), |
2982 | d_inode(dentry->d_parent), name, | |
c3c188b2 DH |
2983 | inode_mode_to_security_class(mode), |
2984 | &newsid); | |
2985 | if (rc) | |
2986 | return rc; | |
d47be3df | 2987 | |
aa8e712c SS |
2988 | return security_sid_to_context(&selinux_state, newsid, (char **)ctx, |
2989 | ctxlen); | |
d47be3df DQ |
2990 | } |
2991 | ||
a518b0a5 VG |
2992 | static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, |
2993 | struct qstr *name, | |
2994 | const struct cred *old, | |
2995 | struct cred *new) | |
2996 | { | |
2997 | u32 newsid; | |
2998 | int rc; | |
2999 | struct task_security_struct *tsec; | |
3000 | ||
3001 | rc = selinux_determine_inode_label(old->security, | |
3002 | d_inode(dentry->d_parent), name, | |
3003 | inode_mode_to_security_class(mode), | |
3004 | &newsid); | |
3005 | if (rc) | |
3006 | return rc; | |
3007 | ||
3008 | tsec = new->security; | |
3009 | tsec->create_sid = newsid; | |
3010 | return 0; | |
3011 | } | |
3012 | ||
5e41ff9e | 3013 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
3014 | const struct qstr *qstr, |
3015 | const char **name, | |
2a7dba39 | 3016 | void **value, size_t *len) |
5e41ff9e | 3017 | { |
5fb49870 | 3018 | const struct task_security_struct *tsec = current_security(); |
5e41ff9e | 3019 | struct superblock_security_struct *sbsec; |
c0d4f464 | 3020 | u32 newsid, clen; |
5e41ff9e | 3021 | int rc; |
9548906b | 3022 | char *context; |
5e41ff9e | 3023 | |
5e41ff9e | 3024 | sbsec = dir->i_sb->s_security; |
5e41ff9e | 3025 | |
275bb41e DH |
3026 | newsid = tsec->create_sid; |
3027 | ||
c957f6df | 3028 | rc = selinux_determine_inode_label(current_security(), |
c3c188b2 DH |
3029 | dir, qstr, |
3030 | inode_mode_to_security_class(inode->i_mode), | |
3031 | &newsid); | |
3032 | if (rc) | |
3033 | return rc; | |
5e41ff9e | 3034 | |
296fddf7 | 3035 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 3036 | if (sbsec->flags & SE_SBINITIALIZED) { |
296fddf7 EP |
3037 | struct inode_security_struct *isec = inode->i_security; |
3038 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
3039 | isec->sid = newsid; | |
6f3be9f5 | 3040 | isec->initialized = LABEL_INITIALIZED; |
296fddf7 | 3041 | } |
5e41ff9e | 3042 | |
aa8e712c | 3043 | if (!selinux_state.initialized || !(sbsec->flags & SBLABEL_MNT)) |
25a74f3b SS |
3044 | return -EOPNOTSUPP; |
3045 | ||
9548906b TH |
3046 | if (name) |
3047 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 3048 | |
570bc1c2 | 3049 | if (value && len) { |
aa8e712c SS |
3050 | rc = security_sid_to_context_force(&selinux_state, newsid, |
3051 | &context, &clen); | |
9548906b | 3052 | if (rc) |
570bc1c2 | 3053 | return rc; |
570bc1c2 SS |
3054 | *value = context; |
3055 | *len = clen; | |
5e41ff9e | 3056 | } |
5e41ff9e | 3057 | |
5e41ff9e SS |
3058 | return 0; |
3059 | } | |
3060 | ||
4acdaf27 | 3061 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
3062 | { |
3063 | return may_create(dir, dentry, SECCLASS_FILE); | |
3064 | } | |
3065 | ||
1da177e4 LT |
3066 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
3067 | { | |
1da177e4 LT |
3068 | return may_link(dir, old_dentry, MAY_LINK); |
3069 | } | |
3070 | ||
1da177e4 LT |
3071 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
3072 | { | |
1da177e4 LT |
3073 | return may_link(dir, dentry, MAY_UNLINK); |
3074 | } | |
3075 | ||
3076 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
3077 | { | |
3078 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
3079 | } | |
3080 | ||
18bb1db3 | 3081 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
3082 | { |
3083 | return may_create(dir, dentry, SECCLASS_DIR); | |
3084 | } | |
3085 | ||
1da177e4 LT |
3086 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
3087 | { | |
3088 | return may_link(dir, dentry, MAY_RMDIR); | |
3089 | } | |
3090 | ||
1a67aafb | 3091 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 3092 | { |
1da177e4 LT |
3093 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
3094 | } | |
3095 | ||
1da177e4 | 3096 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 3097 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
3098 | { |
3099 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
3100 | } | |
3101 | ||
1da177e4 LT |
3102 | static int selinux_inode_readlink(struct dentry *dentry) |
3103 | { | |
88e67f3b DH |
3104 | const struct cred *cred = current_cred(); |
3105 | ||
2875fa00 | 3106 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
3107 | } |
3108 | ||
bda0be7a N |
3109 | static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, |
3110 | bool rcu) | |
1da177e4 | 3111 | { |
88e67f3b | 3112 | const struct cred *cred = current_cred(); |
bda0be7a N |
3113 | struct common_audit_data ad; |
3114 | struct inode_security_struct *isec; | |
3115 | u32 sid; | |
1da177e4 | 3116 | |
bda0be7a N |
3117 | validate_creds(cred); |
3118 | ||
3119 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
3120 | ad.u.dentry = dentry; | |
3121 | sid = cred_sid(cred); | |
5d226df4 AG |
3122 | isec = inode_security_rcu(inode, rcu); |
3123 | if (IS_ERR(isec)) | |
3124 | return PTR_ERR(isec); | |
bda0be7a | 3125 | |
6b6bc620 SS |
3126 | return avc_has_perm_flags(&selinux_state, |
3127 | sid, isec->sid, isec->sclass, FILE__READ, &ad, | |
bda0be7a | 3128 | rcu ? MAY_NOT_BLOCK : 0); |
1da177e4 LT |
3129 | } |
3130 | ||
d4cf970d EP |
3131 | static noinline int audit_inode_permission(struct inode *inode, |
3132 | u32 perms, u32 audited, u32 denied, | |
626b9740 | 3133 | int result, |
d4cf970d | 3134 | unsigned flags) |
1da177e4 | 3135 | { |
b782e0a6 | 3136 | struct common_audit_data ad; |
d4cf970d EP |
3137 | struct inode_security_struct *isec = inode->i_security; |
3138 | int rc; | |
3139 | ||
50c205f5 | 3140 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
3141 | ad.u.inode = inode; |
3142 | ||
6b6bc620 SS |
3143 | rc = slow_avc_audit(&selinux_state, |
3144 | current_sid(), isec->sid, isec->sclass, perms, | |
626b9740 | 3145 | audited, denied, result, &ad, flags); |
d4cf970d EP |
3146 | if (rc) |
3147 | return rc; | |
3148 | return 0; | |
3149 | } | |
3150 | ||
e74f71eb | 3151 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 3152 | { |
88e67f3b | 3153 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
3154 | u32 perms; |
3155 | bool from_access; | |
cf1dd1da | 3156 | unsigned flags = mask & MAY_NOT_BLOCK; |
2e334057 EP |
3157 | struct inode_security_struct *isec; |
3158 | u32 sid; | |
3159 | struct av_decision avd; | |
3160 | int rc, rc2; | |
3161 | u32 audited, denied; | |
1da177e4 | 3162 | |
b782e0a6 | 3163 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
3164 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
3165 | ||
b782e0a6 EP |
3166 | /* No permission to check. Existence test. */ |
3167 | if (!mask) | |
1da177e4 | 3168 | return 0; |
1da177e4 | 3169 | |
2e334057 | 3170 | validate_creds(cred); |
b782e0a6 | 3171 | |
2e334057 EP |
3172 | if (unlikely(IS_PRIVATE(inode))) |
3173 | return 0; | |
b782e0a6 EP |
3174 | |
3175 | perms = file_mask_to_av(inode->i_mode, mask); | |
3176 | ||
2e334057 | 3177 | sid = cred_sid(cred); |
5d226df4 AG |
3178 | isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK); |
3179 | if (IS_ERR(isec)) | |
3180 | return PTR_ERR(isec); | |
2e334057 | 3181 | |
6b6bc620 SS |
3182 | rc = avc_has_perm_noaudit(&selinux_state, |
3183 | sid, isec->sid, isec->sclass, perms, 0, &avd); | |
2e334057 EP |
3184 | audited = avc_audit_required(perms, &avd, rc, |
3185 | from_access ? FILE__AUDIT_ACCESS : 0, | |
3186 | &denied); | |
3187 | if (likely(!audited)) | |
3188 | return rc; | |
3189 | ||
626b9740 | 3190 | rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags); |
2e334057 EP |
3191 | if (rc2) |
3192 | return rc2; | |
3193 | return rc; | |
1da177e4 LT |
3194 | } |
3195 | ||
3196 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
3197 | { | |
88e67f3b | 3198 | const struct cred *cred = current_cred(); |
ccb54478 | 3199 | struct inode *inode = d_backing_inode(dentry); |
bc6a6008 | 3200 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 3201 | __u32 av = FILE__WRITE; |
1da177e4 | 3202 | |
bc6a6008 AW |
3203 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
3204 | if (ia_valid & ATTR_FORCE) { | |
3205 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
3206 | ATTR_FORCE); | |
3207 | if (!ia_valid) | |
3208 | return 0; | |
3209 | } | |
1da177e4 | 3210 | |
bc6a6008 AW |
3211 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
3212 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 3213 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 3214 | |
aa8e712c | 3215 | if (selinux_policycap_openperm() && |
ccb54478 SS |
3216 | inode->i_sb->s_magic != SOCKFS_MAGIC && |
3217 | (ia_valid & ATTR_SIZE) && | |
3218 | !(ia_valid & ATTR_FILE)) | |
95dbf739 EP |
3219 | av |= FILE__OPEN; |
3220 | ||
3221 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
3222 | } |
3223 | ||
3f7036a0 | 3224 | static int selinux_inode_getattr(const struct path *path) |
1da177e4 | 3225 | { |
3f7036a0 | 3226 | return path_has_perm(current_cred(), path, FILE__GETATTR); |
1da177e4 LT |
3227 | } |
3228 | ||
db59000a SS |
3229 | static bool has_cap_mac_admin(bool audit) |
3230 | { | |
3231 | const struct cred *cred = current_cred(); | |
3232 | int cap_audit = audit ? SECURITY_CAP_AUDIT : SECURITY_CAP_NOAUDIT; | |
3233 | ||
3234 | if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, cap_audit)) | |
3235 | return false; | |
3236 | if (cred_has_capability(cred, CAP_MAC_ADMIN, cap_audit, true)) | |
3237 | return false; | |
3238 | return true; | |
3239 | } | |
3240 | ||
8f0cfa52 DH |
3241 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
3242 | const void *value, size_t size, int flags) | |
1da177e4 | 3243 | { |
c6f493d6 | 3244 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3245 | struct inode_security_struct *isec; |
1da177e4 | 3246 | struct superblock_security_struct *sbsec; |
2bf49690 | 3247 | struct common_audit_data ad; |
275bb41e | 3248 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
3249 | int rc = 0; |
3250 | ||
6b240306 EB |
3251 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3252 | rc = cap_inode_setxattr(dentry, name, value, size, flags); | |
3253 | if (rc) | |
3254 | return rc; | |
3255 | ||
3256 | /* Not an attribute we recognize, so just check the | |
3257 | ordinary setattr permission. */ | |
3258 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3259 | } | |
1da177e4 LT |
3260 | |
3261 | sbsec = inode->i_sb->s_security; | |
12f348b9 | 3262 | if (!(sbsec->flags & SBLABEL_MNT)) |
1da177e4 LT |
3263 | return -EOPNOTSUPP; |
3264 | ||
2e149670 | 3265 | if (!inode_owner_or_capable(inode)) |
1da177e4 LT |
3266 | return -EPERM; |
3267 | ||
50c205f5 | 3268 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 3269 | ad.u.dentry = dentry; |
1da177e4 | 3270 | |
20cdef8d | 3271 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
3272 | rc = avc_has_perm(&selinux_state, |
3273 | sid, isec->sid, isec->sclass, | |
1da177e4 LT |
3274 | FILE__RELABELFROM, &ad); |
3275 | if (rc) | |
3276 | return rc; | |
3277 | ||
aa8e712c SS |
3278 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3279 | GFP_KERNEL); | |
12b29f34 | 3280 | if (rc == -EINVAL) { |
db59000a | 3281 | if (!has_cap_mac_admin(true)) { |
d6ea83ec EP |
3282 | struct audit_buffer *ab; |
3283 | size_t audit_size; | |
d6ea83ec EP |
3284 | |
3285 | /* We strip a nul only if it is at the end, otherwise the | |
3286 | * context contains a nul and we should audit that */ | |
e3fea3f7 | 3287 | if (value) { |
add24372 CIK |
3288 | const char *str = value; |
3289 | ||
e3fea3f7 AV |
3290 | if (str[size - 1] == '\0') |
3291 | audit_size = size - 1; | |
3292 | else | |
3293 | audit_size = size; | |
3294 | } else { | |
e3fea3f7 AV |
3295 | audit_size = 0; |
3296 | } | |
d6ea83ec EP |
3297 | ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); |
3298 | audit_log_format(ab, "op=setxattr invalid_context="); | |
3299 | audit_log_n_untrustedstring(ab, value, audit_size); | |
3300 | audit_log_end(ab); | |
3301 | ||
12b29f34 | 3302 | return rc; |
d6ea83ec | 3303 | } |
aa8e712c SS |
3304 | rc = security_context_to_sid_force(&selinux_state, value, |
3305 | size, &newsid); | |
12b29f34 | 3306 | } |
1da177e4 LT |
3307 | if (rc) |
3308 | return rc; | |
3309 | ||
6b6bc620 SS |
3310 | rc = avc_has_perm(&selinux_state, |
3311 | sid, newsid, isec->sclass, | |
1da177e4 LT |
3312 | FILE__RELABELTO, &ad); |
3313 | if (rc) | |
3314 | return rc; | |
3315 | ||
aa8e712c SS |
3316 | rc = security_validate_transition(&selinux_state, isec->sid, newsid, |
3317 | sid, isec->sclass); | |
1da177e4 LT |
3318 | if (rc) |
3319 | return rc; | |
3320 | ||
6b6bc620 SS |
3321 | return avc_has_perm(&selinux_state, |
3322 | newsid, | |
1da177e4 LT |
3323 | sbsec->sid, |
3324 | SECCLASS_FILESYSTEM, | |
3325 | FILESYSTEM__ASSOCIATE, | |
3326 | &ad); | |
3327 | } | |
3328 | ||
8f0cfa52 | 3329 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 3330 | const void *value, size_t size, |
8f0cfa52 | 3331 | int flags) |
1da177e4 | 3332 | { |
c6f493d6 | 3333 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3334 | struct inode_security_struct *isec; |
1da177e4 LT |
3335 | u32 newsid; |
3336 | int rc; | |
3337 | ||
3338 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
3339 | /* Not an attribute we recognize, so nothing to do. */ | |
3340 | return; | |
3341 | } | |
3342 | ||
aa8e712c SS |
3343 | rc = security_context_to_sid_force(&selinux_state, value, size, |
3344 | &newsid); | |
1da177e4 | 3345 | if (rc) { |
12b29f34 SS |
3346 | printk(KERN_ERR "SELinux: unable to map context to SID" |
3347 | "for (%s, %lu), rc=%d\n", | |
3348 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
3349 | return; |
3350 | } | |
3351 | ||
20cdef8d | 3352 | isec = backing_inode_security(dentry); |
9287aed2 | 3353 | spin_lock(&isec->lock); |
aa9c2669 | 3354 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3355 | isec->sid = newsid; |
6f3be9f5 | 3356 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3357 | spin_unlock(&isec->lock); |
aa9c2669 | 3358 | |
1da177e4 LT |
3359 | return; |
3360 | } | |
3361 | ||
8f0cfa52 | 3362 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 3363 | { |
88e67f3b DH |
3364 | const struct cred *cred = current_cred(); |
3365 | ||
2875fa00 | 3366 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3367 | } |
3368 | ||
828dfe1d | 3369 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 3370 | { |
88e67f3b DH |
3371 | const struct cred *cred = current_cred(); |
3372 | ||
2875fa00 | 3373 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3374 | } |
3375 | ||
8f0cfa52 | 3376 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 3377 | { |
6b240306 EB |
3378 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3379 | int rc = cap_inode_removexattr(dentry, name); | |
3380 | if (rc) | |
3381 | return rc; | |
3382 | ||
3383 | /* Not an attribute we recognize, so just check the | |
3384 | ordinary setattr permission. */ | |
3385 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3386 | } | |
1da177e4 LT |
3387 | |
3388 | /* No one is allowed to remove a SELinux security label. | |
3389 | You can change the label, but all data must be labeled. */ | |
3390 | return -EACCES; | |
3391 | } | |
3392 | ||
d381d8a9 | 3393 | /* |
abc69bb6 | 3394 | * Copy the inode security context value to the user. |
d381d8a9 JM |
3395 | * |
3396 | * Permission check is handled by selinux_inode_getxattr hook. | |
3397 | */ | |
ea861dfd | 3398 | static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 3399 | { |
42492594 DQ |
3400 | u32 size; |
3401 | int error; | |
3402 | char *context = NULL; | |
20cdef8d | 3403 | struct inode_security_struct *isec; |
d381d8a9 | 3404 | |
8c8570fb DK |
3405 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
3406 | return -EOPNOTSUPP; | |
d381d8a9 | 3407 | |
abc69bb6 SS |
3408 | /* |
3409 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3410 | * value even if it is not defined by current policy; otherwise, | |
3411 | * use the in-core value under current policy. | |
3412 | * Use the non-auditing forms of the permission checks since | |
3413 | * getxattr may be called by unprivileged processes commonly | |
3414 | * and lack of permission just means that we fall back to the | |
3415 | * in-core context value, not a denial. | |
3416 | */ | |
20cdef8d | 3417 | isec = inode_security(inode); |
db59000a | 3418 | if (has_cap_mac_admin(false)) |
aa8e712c SS |
3419 | error = security_sid_to_context_force(&selinux_state, |
3420 | isec->sid, &context, | |
abc69bb6 SS |
3421 | &size); |
3422 | else | |
aa8e712c SS |
3423 | error = security_sid_to_context(&selinux_state, isec->sid, |
3424 | &context, &size); | |
42492594 DQ |
3425 | if (error) |
3426 | return error; | |
3427 | error = size; | |
3428 | if (alloc) { | |
3429 | *buffer = context; | |
3430 | goto out_nofree; | |
3431 | } | |
3432 | kfree(context); | |
3433 | out_nofree: | |
3434 | return error; | |
1da177e4 LT |
3435 | } |
3436 | ||
3437 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 3438 | const void *value, size_t size, int flags) |
1da177e4 | 3439 | { |
2c97165b | 3440 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
1da177e4 LT |
3441 | u32 newsid; |
3442 | int rc; | |
3443 | ||
3444 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3445 | return -EOPNOTSUPP; | |
3446 | ||
3447 | if (!value || !size) | |
3448 | return -EACCES; | |
3449 | ||
aa8e712c SS |
3450 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3451 | GFP_KERNEL); | |
1da177e4 LT |
3452 | if (rc) |
3453 | return rc; | |
3454 | ||
9287aed2 | 3455 | spin_lock(&isec->lock); |
aa9c2669 | 3456 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3457 | isec->sid = newsid; |
6f3be9f5 | 3458 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3459 | spin_unlock(&isec->lock); |
1da177e4 LT |
3460 | return 0; |
3461 | } | |
3462 | ||
3463 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3464 | { | |
3465 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3466 | if (buffer && len <= buffer_size) | |
3467 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3468 | return len; | |
3469 | } | |
3470 | ||
d6335d77 | 3471 | static void selinux_inode_getsecid(struct inode *inode, u32 *secid) |
713a04ae | 3472 | { |
e817c2f3 | 3473 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
713a04ae AD |
3474 | *secid = isec->sid; |
3475 | } | |
3476 | ||
56909eb3 VG |
3477 | static int selinux_inode_copy_up(struct dentry *src, struct cred **new) |
3478 | { | |
3479 | u32 sid; | |
3480 | struct task_security_struct *tsec; | |
3481 | struct cred *new_creds = *new; | |
3482 | ||
3483 | if (new_creds == NULL) { | |
3484 | new_creds = prepare_creds(); | |
3485 | if (!new_creds) | |
3486 | return -ENOMEM; | |
3487 | } | |
3488 | ||
3489 | tsec = new_creds->security; | |
3490 | /* Get label from overlay inode and set it in create_sid */ | |
3491 | selinux_inode_getsecid(d_inode(src), &sid); | |
3492 | tsec->create_sid = sid; | |
3493 | *new = new_creds; | |
3494 | return 0; | |
3495 | } | |
3496 | ||
19472b69 VG |
3497 | static int selinux_inode_copy_up_xattr(const char *name) |
3498 | { | |
3499 | /* The copy_up hook above sets the initial context on an inode, but we | |
3500 | * don't then want to overwrite it by blindly copying all the lower | |
3501 | * xattrs up. Instead, we have to filter out SELinux-related xattrs. | |
3502 | */ | |
3503 | if (strcmp(name, XATTR_NAME_SELINUX) == 0) | |
3504 | return 1; /* Discard */ | |
3505 | /* | |
3506 | * Any other attribute apart from SELINUX is not claimed, supported | |
3507 | * by selinux. | |
3508 | */ | |
3509 | return -EOPNOTSUPP; | |
3510 | } | |
3511 | ||
1da177e4 LT |
3512 | /* file security operations */ |
3513 | ||
788e7dd4 | 3514 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3515 | { |
88e67f3b | 3516 | const struct cred *cred = current_cred(); |
496ad9aa | 3517 | struct inode *inode = file_inode(file); |
1da177e4 | 3518 | |
1da177e4 LT |
3519 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3520 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3521 | mask |= MAY_APPEND; | |
3522 | ||
389fb800 PM |
3523 | return file_has_perm(cred, file, |
3524 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3525 | } |
3526 | ||
788e7dd4 YN |
3527 | static int selinux_file_permission(struct file *file, int mask) |
3528 | { | |
496ad9aa | 3529 | struct inode *inode = file_inode(file); |
20dda18b | 3530 | struct file_security_struct *fsec = file->f_security; |
b197367e | 3531 | struct inode_security_struct *isec; |
20dda18b SS |
3532 | u32 sid = current_sid(); |
3533 | ||
389fb800 | 3534 | if (!mask) |
788e7dd4 YN |
3535 | /* No permission to check. Existence test. */ |
3536 | return 0; | |
788e7dd4 | 3537 | |
b197367e | 3538 | isec = inode_security(inode); |
20dda18b | 3539 | if (sid == fsec->sid && fsec->isid == isec->sid && |
6b6bc620 | 3540 | fsec->pseqno == avc_policy_seqno(&selinux_state)) |
83d49856 | 3541 | /* No change since file_open check. */ |
20dda18b SS |
3542 | return 0; |
3543 | ||
788e7dd4 YN |
3544 | return selinux_revalidate_file_permission(file, mask); |
3545 | } | |
3546 | ||
1da177e4 LT |
3547 | static int selinux_file_alloc_security(struct file *file) |
3548 | { | |
3549 | return file_alloc_security(file); | |
3550 | } | |
3551 | ||
3552 | static void selinux_file_free_security(struct file *file) | |
3553 | { | |
3554 | file_free_security(file); | |
3555 | } | |
3556 | ||
fa1aa143 JVS |
3557 | /* |
3558 | * Check whether a task has the ioctl permission and cmd | |
3559 | * operation to an inode. | |
3560 | */ | |
1d2a168a | 3561 | static int ioctl_has_perm(const struct cred *cred, struct file *file, |
fa1aa143 JVS |
3562 | u32 requested, u16 cmd) |
3563 | { | |
3564 | struct common_audit_data ad; | |
3565 | struct file_security_struct *fsec = file->f_security; | |
3566 | struct inode *inode = file_inode(file); | |
20cdef8d | 3567 | struct inode_security_struct *isec; |
fa1aa143 JVS |
3568 | struct lsm_ioctlop_audit ioctl; |
3569 | u32 ssid = cred_sid(cred); | |
3570 | int rc; | |
3571 | u8 driver = cmd >> 8; | |
3572 | u8 xperm = cmd & 0xff; | |
3573 | ||
3574 | ad.type = LSM_AUDIT_DATA_IOCTL_OP; | |
3575 | ad.u.op = &ioctl; | |
3576 | ad.u.op->cmd = cmd; | |
3577 | ad.u.op->path = file->f_path; | |
3578 | ||
3579 | if (ssid != fsec->sid) { | |
6b6bc620 SS |
3580 | rc = avc_has_perm(&selinux_state, |
3581 | ssid, fsec->sid, | |
fa1aa143 JVS |
3582 | SECCLASS_FD, |
3583 | FD__USE, | |
3584 | &ad); | |
3585 | if (rc) | |
3586 | goto out; | |
3587 | } | |
3588 | ||
3589 | if (unlikely(IS_PRIVATE(inode))) | |
3590 | return 0; | |
3591 | ||
20cdef8d | 3592 | isec = inode_security(inode); |
6b6bc620 SS |
3593 | rc = avc_has_extended_perms(&selinux_state, |
3594 | ssid, isec->sid, isec->sclass, | |
3595 | requested, driver, xperm, &ad); | |
fa1aa143 JVS |
3596 | out: |
3597 | return rc; | |
3598 | } | |
3599 | ||
1da177e4 LT |
3600 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
3601 | unsigned long arg) | |
3602 | { | |
88e67f3b | 3603 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3604 | int error = 0; |
1da177e4 | 3605 | |
0b24dcb7 EP |
3606 | switch (cmd) { |
3607 | case FIONREAD: | |
3608 | /* fall through */ | |
3609 | case FIBMAP: | |
3610 | /* fall through */ | |
3611 | case FIGETBSZ: | |
3612 | /* fall through */ | |
2f99c369 | 3613 | case FS_IOC_GETFLAGS: |
0b24dcb7 | 3614 | /* fall through */ |
2f99c369 | 3615 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3616 | error = file_has_perm(cred, file, FILE__GETATTR); |
3617 | break; | |
1da177e4 | 3618 | |
2f99c369 | 3619 | case FS_IOC_SETFLAGS: |
0b24dcb7 | 3620 | /* fall through */ |
2f99c369 | 3621 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3622 | error = file_has_perm(cred, file, FILE__SETATTR); |
3623 | break; | |
3624 | ||
3625 | /* sys_ioctl() checks */ | |
3626 | case FIONBIO: | |
3627 | /* fall through */ | |
3628 | case FIOASYNC: | |
3629 | error = file_has_perm(cred, file, 0); | |
3630 | break; | |
1da177e4 | 3631 | |
0b24dcb7 EP |
3632 | case KDSKBENT: |
3633 | case KDSKBSENT: | |
6a9de491 | 3634 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
8e4ff6f2 | 3635 | SECURITY_CAP_AUDIT, true); |
0b24dcb7 EP |
3636 | break; |
3637 | ||
3638 | /* default case assumes that the command will go | |
3639 | * to the file's ioctl() function. | |
3640 | */ | |
3641 | default: | |
fa1aa143 | 3642 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
0b24dcb7 EP |
3643 | } |
3644 | return error; | |
1da177e4 LT |
3645 | } |
3646 | ||
fcaaade1 SS |
3647 | static int default_noexec; |
3648 | ||
1da177e4 LT |
3649 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3650 | { | |
88e67f3b | 3651 | const struct cred *cred = current_cred(); |
be0554c9 | 3652 | u32 sid = cred_sid(cred); |
d84f4f99 | 3653 | int rc = 0; |
88e67f3b | 3654 | |
fcaaade1 | 3655 | if (default_noexec && |
892e8cac SS |
3656 | (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || |
3657 | (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3658 | /* |
3659 | * We are making executable an anonymous mapping or a | |
3660 | * private file mapping that will also be writable. | |
3661 | * This has an additional check. | |
3662 | */ | |
6b6bc620 SS |
3663 | rc = avc_has_perm(&selinux_state, |
3664 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3665 | PROCESS__EXECMEM, NULL); |
1da177e4 | 3666 | if (rc) |
d84f4f99 | 3667 | goto error; |
1da177e4 | 3668 | } |
1da177e4 LT |
3669 | |
3670 | if (file) { | |
3671 | /* read access is always possible with a mapping */ | |
3672 | u32 av = FILE__READ; | |
3673 | ||
3674 | /* write access only matters if the mapping is shared */ | |
3675 | if (shared && (prot & PROT_WRITE)) | |
3676 | av |= FILE__WRITE; | |
3677 | ||
3678 | if (prot & PROT_EXEC) | |
3679 | av |= FILE__EXECUTE; | |
3680 | ||
88e67f3b | 3681 | return file_has_perm(cred, file, av); |
1da177e4 | 3682 | } |
d84f4f99 DH |
3683 | |
3684 | error: | |
3685 | return rc; | |
1da177e4 LT |
3686 | } |
3687 | ||
e5467859 | 3688 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3689 | { |
b1d9e6b0 | 3690 | int rc = 0; |
1da177e4 | 3691 | |
a2551df7 | 3692 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
98883bfd | 3693 | u32 sid = current_sid(); |
6b6bc620 SS |
3694 | rc = avc_has_perm(&selinux_state, |
3695 | sid, sid, SECCLASS_MEMPROTECT, | |
ed032189 | 3696 | MEMPROTECT__MMAP_ZERO, NULL); |
84336d1a EP |
3697 | } |
3698 | ||
98883bfd | 3699 | return rc; |
e5467859 | 3700 | } |
1da177e4 | 3701 | |
e5467859 AV |
3702 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3703 | unsigned long prot, unsigned long flags) | |
3704 | { | |
3ba4bf5f SS |
3705 | struct common_audit_data ad; |
3706 | int rc; | |
3707 | ||
3708 | if (file) { | |
3709 | ad.type = LSM_AUDIT_DATA_FILE; | |
3710 | ad.u.file = file; | |
3711 | rc = inode_has_perm(current_cred(), file_inode(file), | |
3712 | FILE__MAP, &ad); | |
3713 | if (rc) | |
3714 | return rc; | |
3715 | } | |
3716 | ||
aa8e712c | 3717 | if (selinux_state.checkreqprot) |
1da177e4 LT |
3718 | prot = reqprot; |
3719 | ||
3720 | return file_map_prot_check(file, prot, | |
3721 | (flags & MAP_TYPE) == MAP_SHARED); | |
3722 | } | |
3723 | ||
3724 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3725 | unsigned long reqprot, | |
3726 | unsigned long prot) | |
3727 | { | |
88e67f3b | 3728 | const struct cred *cred = current_cred(); |
be0554c9 | 3729 | u32 sid = cred_sid(cred); |
1da177e4 | 3730 | |
aa8e712c | 3731 | if (selinux_state.checkreqprot) |
1da177e4 LT |
3732 | prot = reqprot; |
3733 | ||
fcaaade1 SS |
3734 | if (default_noexec && |
3735 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3736 | int rc = 0; |
db4c9641 SS |
3737 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3738 | vma->vm_end <= vma->vm_mm->brk) { | |
6b6bc620 SS |
3739 | rc = avc_has_perm(&selinux_state, |
3740 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3741 | PROCESS__EXECHEAP, NULL); |
db4c9641 | 3742 | } else if (!vma->vm_file && |
c2316dbf SS |
3743 | ((vma->vm_start <= vma->vm_mm->start_stack && |
3744 | vma->vm_end >= vma->vm_mm->start_stack) || | |
d17af505 | 3745 | vma_is_stack_for_current(vma))) { |
6b6bc620 SS |
3746 | rc = avc_has_perm(&selinux_state, |
3747 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3748 | PROCESS__EXECSTACK, NULL); |
db4c9641 SS |
3749 | } else if (vma->vm_file && vma->anon_vma) { |
3750 | /* | |
3751 | * We are making executable a file mapping that has | |
3752 | * had some COW done. Since pages might have been | |
3753 | * written, check ability to execute the possibly | |
3754 | * modified content. This typically should only | |
3755 | * occur for text relocations. | |
3756 | */ | |
d84f4f99 | 3757 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3758 | } |