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 |
e9193288 | 277 | * invalid. The @dentry parameter should be set to a dentry of the inode. |
5d226df4 AG |
278 | */ |
279 | static int __inode_security_revalidate(struct inode *inode, | |
e9193288 | 280 | struct dentry *dentry, |
5d226df4 AG |
281 | bool may_sleep) |
282 | { | |
283 | struct inode_security_struct *isec = inode->i_security; | |
284 | ||
285 | might_sleep_if(may_sleep); | |
286 | ||
aa8e712c SS |
287 | if (selinux_state.initialized && |
288 | isec->initialized != LABEL_INITIALIZED) { | |
5d226df4 AG |
289 | if (!may_sleep) |
290 | return -ECHILD; | |
291 | ||
292 | /* | |
293 | * Try reloading the inode security label. This will fail if | |
294 | * @opt_dentry is NULL and no dentry for this inode can be | |
295 | * found; in that case, continue using the old label. | |
296 | */ | |
e9193288 | 297 | inode_doinit_with_dentry(inode, dentry); |
5d226df4 AG |
298 | } |
299 | return 0; | |
300 | } | |
301 | ||
5d226df4 AG |
302 | static struct inode_security_struct *inode_security_novalidate(struct inode *inode) |
303 | { | |
304 | return inode->i_security; | |
305 | } | |
306 | ||
307 | static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) | |
308 | { | |
309 | int error; | |
310 | ||
311 | error = __inode_security_revalidate(inode, NULL, !rcu); | |
312 | if (error) | |
313 | return ERR_PTR(error); | |
314 | return inode->i_security; | |
315 | } | |
316 | ||
83da53c5 AG |
317 | /* |
318 | * Get the security label of an inode. | |
319 | */ | |
320 | static struct inode_security_struct *inode_security(struct inode *inode) | |
321 | { | |
5d226df4 | 322 | __inode_security_revalidate(inode, NULL, true); |
83da53c5 AG |
323 | return inode->i_security; |
324 | } | |
325 | ||
2c97165b PM |
326 | static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) |
327 | { | |
328 | struct inode *inode = d_backing_inode(dentry); | |
329 | ||
330 | return inode->i_security; | |
331 | } | |
332 | ||
83da53c5 AG |
333 | /* |
334 | * Get the security label of a dentry's backing inode. | |
335 | */ | |
336 | static struct inode_security_struct *backing_inode_security(struct dentry *dentry) | |
337 | { | |
338 | struct inode *inode = d_backing_inode(dentry); | |
339 | ||
5d226df4 | 340 | __inode_security_revalidate(inode, dentry, true); |
83da53c5 AG |
341 | return inode->i_security; |
342 | } | |
343 | ||
3dc91d43 SR |
344 | static void inode_free_rcu(struct rcu_head *head) |
345 | { | |
346 | struct inode_security_struct *isec; | |
347 | ||
348 | isec = container_of(head, struct inode_security_struct, rcu); | |
349 | kmem_cache_free(sel_inode_cache, isec); | |
350 | } | |
351 | ||
1da177e4 LT |
352 | static void inode_free_security(struct inode *inode) |
353 | { | |
354 | struct inode_security_struct *isec = inode->i_security; | |
355 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
356 | ||
9629d04a WL |
357 | /* |
358 | * As not all inode security structures are in a list, we check for | |
359 | * empty list outside of the lock to make sure that we won't waste | |
360 | * time taking a lock doing nothing. | |
361 | * | |
362 | * The list_del_init() function can be safely called more than once. | |
363 | * It should not be possible for this function to be called with | |
364 | * concurrent list_add(), but for better safety against future changes | |
365 | * in the code, we use list_empty_careful() here. | |
366 | */ | |
367 | if (!list_empty_careful(&isec->list)) { | |
368 | spin_lock(&sbsec->isec_lock); | |
1da177e4 | 369 | list_del_init(&isec->list); |
9629d04a WL |
370 | spin_unlock(&sbsec->isec_lock); |
371 | } | |
1da177e4 | 372 | |
3dc91d43 SR |
373 | /* |
374 | * The inode may still be referenced in a path walk and | |
375 | * a call to selinux_inode_permission() can be made | |
376 | * after inode_free_security() is called. Ideally, the VFS | |
377 | * wouldn't do this, but fixing that is a much harder | |
378 | * job. For now, simply free the i_security via RCU, and | |
379 | * leave the current inode->i_security pointer intact. | |
380 | * The inode will be freed after the RCU grace period too. | |
381 | */ | |
382 | call_rcu(&isec->rcu, inode_free_rcu); | |
1da177e4 LT |
383 | } |
384 | ||
385 | static int file_alloc_security(struct file *file) | |
386 | { | |
1da177e4 | 387 | struct file_security_struct *fsec; |
275bb41e | 388 | u32 sid = current_sid(); |
1da177e4 | 389 | |
63205654 | 390 | fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL); |
1da177e4 LT |
391 | if (!fsec) |
392 | return -ENOMEM; | |
393 | ||
275bb41e DH |
394 | fsec->sid = sid; |
395 | fsec->fown_sid = sid; | |
1da177e4 LT |
396 | file->f_security = fsec; |
397 | ||
398 | return 0; | |
399 | } | |
400 | ||
401 | static void file_free_security(struct file *file) | |
402 | { | |
403 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 | 404 | file->f_security = NULL; |
63205654 | 405 | kmem_cache_free(file_security_cache, fsec); |
1da177e4 LT |
406 | } |
407 | ||
408 | static int superblock_alloc_security(struct super_block *sb) | |
409 | { | |
410 | struct superblock_security_struct *sbsec; | |
411 | ||
89d155ef | 412 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
413 | if (!sbsec) |
414 | return -ENOMEM; | |
415 | ||
bc7e982b | 416 | mutex_init(&sbsec->lock); |
1da177e4 LT |
417 | INIT_LIST_HEAD(&sbsec->isec_head); |
418 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
419 | sbsec->sb = sb; |
420 | sbsec->sid = SECINITSID_UNLABELED; | |
421 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 422 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
423 | sb->s_security = sbsec; |
424 | ||
425 | return 0; | |
426 | } | |
427 | ||
428 | static void superblock_free_security(struct super_block *sb) | |
429 | { | |
430 | struct superblock_security_struct *sbsec = sb->s_security; | |
1da177e4 LT |
431 | sb->s_security = NULL; |
432 | kfree(sbsec); | |
433 | } | |
434 | ||
1da177e4 LT |
435 | static inline int inode_doinit(struct inode *inode) |
436 | { | |
437 | return inode_doinit_with_dentry(inode, NULL); | |
438 | } | |
439 | ||
440 | enum { | |
31e87930 | 441 | Opt_error = -1, |
1da177e4 LT |
442 | Opt_context = 1, |
443 | Opt_fscontext = 2, | |
c9180a57 EP |
444 | Opt_defcontext = 3, |
445 | Opt_rootcontext = 4, | |
11689d47 | 446 | Opt_labelsupport = 5, |
d355987f | 447 | Opt_nextmntopt = 6, |
1da177e4 LT |
448 | }; |
449 | ||
d355987f EP |
450 | #define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) |
451 | ||
a447c093 | 452 | static const match_table_t tokens = { |
832cbd9a EP |
453 | {Opt_context, CONTEXT_STR "%s"}, |
454 | {Opt_fscontext, FSCONTEXT_STR "%s"}, | |
455 | {Opt_defcontext, DEFCONTEXT_STR "%s"}, | |
456 | {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, | |
11689d47 | 457 | {Opt_labelsupport, LABELSUPP_STR}, |
31e87930 | 458 | {Opt_error, NULL}, |
1da177e4 LT |
459 | }; |
460 | ||
461 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
462 | ||
c312feb2 EP |
463 | static int may_context_mount_sb_relabel(u32 sid, |
464 | struct superblock_security_struct *sbsec, | |
275bb41e | 465 | const struct cred *cred) |
c312feb2 | 466 | { |
275bb41e | 467 | const struct task_security_struct *tsec = cred->security; |
c312feb2 EP |
468 | int rc; |
469 | ||
6b6bc620 SS |
470 | rc = avc_has_perm(&selinux_state, |
471 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
472 | FILESYSTEM__RELABELFROM, NULL); |
473 | if (rc) | |
474 | return rc; | |
475 | ||
6b6bc620 SS |
476 | rc = avc_has_perm(&selinux_state, |
477 | tsec->sid, sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
478 | FILESYSTEM__RELABELTO, NULL); |
479 | return rc; | |
480 | } | |
481 | ||
0808925e EP |
482 | static int may_context_mount_inode_relabel(u32 sid, |
483 | struct superblock_security_struct *sbsec, | |
275bb41e | 484 | const struct cred *cred) |
0808925e | 485 | { |
275bb41e | 486 | const struct task_security_struct *tsec = cred->security; |
0808925e | 487 | int rc; |
6b6bc620 SS |
488 | rc = avc_has_perm(&selinux_state, |
489 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
490 | FILESYSTEM__RELABELFROM, NULL); |
491 | if (rc) | |
492 | return rc; | |
493 | ||
6b6bc620 SS |
494 | rc = avc_has_perm(&selinux_state, |
495 | sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
496 | FILESYSTEM__ASSOCIATE, NULL); |
497 | return rc; | |
498 | } | |
499 | ||
b43e725d EP |
500 | static int selinux_is_sblabel_mnt(struct super_block *sb) |
501 | { | |
502 | struct superblock_security_struct *sbsec = sb->s_security; | |
503 | ||
d5f3a5f6 MS |
504 | return sbsec->behavior == SECURITY_FS_USE_XATTR || |
505 | sbsec->behavior == SECURITY_FS_USE_TRANS || | |
506 | sbsec->behavior == SECURITY_FS_USE_TASK || | |
9fc2b4b4 | 507 | sbsec->behavior == SECURITY_FS_USE_NATIVE || |
d5f3a5f6 MS |
508 | /* Special handling. Genfs but also in-core setxattr handler */ |
509 | !strcmp(sb->s_type->name, "sysfs") || | |
510 | !strcmp(sb->s_type->name, "pstore") || | |
511 | !strcmp(sb->s_type->name, "debugfs") || | |
a2c7c6fb | 512 | !strcmp(sb->s_type->name, "tracefs") || |
2651225b | 513 | !strcmp(sb->s_type->name, "rootfs") || |
aa8e712c | 514 | (selinux_policycap_cgroupseclabel() && |
2651225b SS |
515 | (!strcmp(sb->s_type->name, "cgroup") || |
516 | !strcmp(sb->s_type->name, "cgroup2"))); | |
b43e725d EP |
517 | } |
518 | ||
c9180a57 | 519 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 520 | { |
1da177e4 | 521 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 | 522 | struct dentry *root = sb->s_root; |
c6f493d6 | 523 | struct inode *root_inode = d_backing_inode(root); |
c9180a57 | 524 | int rc = 0; |
1da177e4 | 525 | |
c9180a57 EP |
526 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
527 | /* Make sure that the xattr handler exists and that no | |
528 | error other than -ENODATA is returned by getxattr on | |
529 | the root directory. -ENODATA is ok, as this may be | |
530 | the first boot of the SELinux kernel before we have | |
531 | assigned xattr values to the filesystem. */ | |
5d6c3191 | 532 | if (!(root_inode->i_opflags & IOP_XATTR)) { |
29b1deb2 LT |
533 | printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " |
534 | "xattr support\n", sb->s_id, sb->s_type->name); | |
c9180a57 EP |
535 | rc = -EOPNOTSUPP; |
536 | goto out; | |
537 | } | |
5d6c3191 AG |
538 | |
539 | rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); | |
c9180a57 EP |
540 | if (rc < 0 && rc != -ENODATA) { |
541 | if (rc == -EOPNOTSUPP) | |
542 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
29b1deb2 LT |
543 | "%s) has no security xattr handler\n", |
544 | sb->s_id, sb->s_type->name); | |
c9180a57 EP |
545 | else |
546 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
29b1deb2 LT |
547 | "%s) getxattr errno %d\n", sb->s_id, |
548 | sb->s_type->name, -rc); | |
c9180a57 EP |
549 | goto out; |
550 | } | |
551 | } | |
1da177e4 | 552 | |
eadcabc6 | 553 | sbsec->flags |= SE_SBINITIALIZED; |
0b4d3452 SM |
554 | |
555 | /* | |
556 | * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply | |
557 | * leave the flag untouched because sb_clone_mnt_opts might be handing | |
558 | * us a superblock that needs the flag to be cleared. | |
559 | */ | |
b43e725d | 560 | if (selinux_is_sblabel_mnt(sb)) |
12f348b9 | 561 | sbsec->flags |= SBLABEL_MNT; |
0b4d3452 SM |
562 | else |
563 | sbsec->flags &= ~SBLABEL_MNT; | |
ddd29ec6 | 564 | |
c9180a57 EP |
565 | /* Initialize the root inode. */ |
566 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 567 | |
c9180a57 EP |
568 | /* Initialize any other inodes associated with the superblock, e.g. |
569 | inodes created prior to initial policy load or inodes created | |
570 | during get_sb by a pseudo filesystem that directly | |
571 | populates itself. */ | |
572 | spin_lock(&sbsec->isec_lock); | |
573 | next_inode: | |
574 | if (!list_empty(&sbsec->isec_head)) { | |
575 | struct inode_security_struct *isec = | |
576 | list_entry(sbsec->isec_head.next, | |
577 | struct inode_security_struct, list); | |
578 | struct inode *inode = isec->inode; | |
923190d3 | 579 | list_del_init(&isec->list); |
c9180a57 EP |
580 | spin_unlock(&sbsec->isec_lock); |
581 | inode = igrab(inode); | |
582 | if (inode) { | |
583 | if (!IS_PRIVATE(inode)) | |
584 | inode_doinit(inode); | |
585 | iput(inode); | |
586 | } | |
587 | spin_lock(&sbsec->isec_lock); | |
c9180a57 EP |
588 | goto next_inode; |
589 | } | |
590 | spin_unlock(&sbsec->isec_lock); | |
591 | out: | |
592 | return rc; | |
593 | } | |
1da177e4 | 594 | |
c9180a57 EP |
595 | /* |
596 | * This function should allow an FS to ask what it's mount security | |
597 | * options were so it can use those later for submounts, displaying | |
598 | * mount options, or whatever. | |
599 | */ | |
600 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
e0007529 | 601 | struct security_mnt_opts *opts) |
c9180a57 EP |
602 | { |
603 | int rc = 0, i; | |
604 | struct superblock_security_struct *sbsec = sb->s_security; | |
605 | char *context = NULL; | |
606 | u32 len; | |
607 | char tmp; | |
1da177e4 | 608 | |
e0007529 | 609 | security_init_mnt_opts(opts); |
1da177e4 | 610 | |
0d90a7ec | 611 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
c9180a57 | 612 | return -EINVAL; |
1da177e4 | 613 | |
aa8e712c | 614 | if (!selinux_state.initialized) |
c9180a57 | 615 | return -EINVAL; |
1da177e4 | 616 | |
af8e50cc EP |
617 | /* make sure we always check enough bits to cover the mask */ |
618 | BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); | |
619 | ||
0d90a7ec | 620 | tmp = sbsec->flags & SE_MNTMASK; |
c9180a57 | 621 | /* count the number of mount options for this sb */ |
af8e50cc | 622 | for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { |
c9180a57 | 623 | if (tmp & 0x01) |
e0007529 | 624 | opts->num_mnt_opts++; |
c9180a57 EP |
625 | tmp >>= 1; |
626 | } | |
11689d47 | 627 | /* Check if the Label support flag is set */ |
0b4bdb35 | 628 | if (sbsec->flags & SBLABEL_MNT) |
11689d47 | 629 | opts->num_mnt_opts++; |
1da177e4 | 630 | |
e0007529 EP |
631 | opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); |
632 | if (!opts->mnt_opts) { | |
c9180a57 EP |
633 | rc = -ENOMEM; |
634 | goto out_free; | |
635 | } | |
1da177e4 | 636 | |
e0007529 EP |
637 | opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); |
638 | if (!opts->mnt_opts_flags) { | |
c9180a57 EP |
639 | rc = -ENOMEM; |
640 | goto out_free; | |
641 | } | |
1da177e4 | 642 | |
c9180a57 EP |
643 | i = 0; |
644 | if (sbsec->flags & FSCONTEXT_MNT) { | |
aa8e712c SS |
645 | rc = security_sid_to_context(&selinux_state, sbsec->sid, |
646 | &context, &len); | |
c9180a57 EP |
647 | if (rc) |
648 | goto out_free; | |
e0007529 EP |
649 | opts->mnt_opts[i] = context; |
650 | opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; | |
c9180a57 EP |
651 | } |
652 | if (sbsec->flags & CONTEXT_MNT) { | |
aa8e712c SS |
653 | rc = security_sid_to_context(&selinux_state, |
654 | sbsec->mntpoint_sid, | |
655 | &context, &len); | |
c9180a57 EP |
656 | if (rc) |
657 | goto out_free; | |
e0007529 EP |
658 | opts->mnt_opts[i] = context; |
659 | opts->mnt_opts_flags[i++] = CONTEXT_MNT; | |
c9180a57 EP |
660 | } |
661 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
aa8e712c SS |
662 | rc = security_sid_to_context(&selinux_state, sbsec->def_sid, |
663 | &context, &len); | |
c9180a57 EP |
664 | if (rc) |
665 | goto out_free; | |
e0007529 EP |
666 | opts->mnt_opts[i] = context; |
667 | opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
668 | } |
669 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
670 | struct dentry *root = sbsec->sb->s_root; |
671 | struct inode_security_struct *isec = backing_inode_security(root); | |
0808925e | 672 | |
aa8e712c SS |
673 | rc = security_sid_to_context(&selinux_state, isec->sid, |
674 | &context, &len); | |
c9180a57 EP |
675 | if (rc) |
676 | goto out_free; | |
e0007529 EP |
677 | opts->mnt_opts[i] = context; |
678 | opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; | |
c9180a57 | 679 | } |
12f348b9 | 680 | if (sbsec->flags & SBLABEL_MNT) { |
11689d47 | 681 | opts->mnt_opts[i] = NULL; |
12f348b9 | 682 | opts->mnt_opts_flags[i++] = SBLABEL_MNT; |
11689d47 | 683 | } |
1da177e4 | 684 | |
e0007529 | 685 | BUG_ON(i != opts->num_mnt_opts); |
1da177e4 | 686 | |
c9180a57 EP |
687 | return 0; |
688 | ||
689 | out_free: | |
e0007529 | 690 | security_free_mnt_opts(opts); |
c9180a57 EP |
691 | return rc; |
692 | } | |
1da177e4 | 693 | |
c9180a57 EP |
694 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
695 | u32 old_sid, u32 new_sid) | |
696 | { | |
0d90a7ec DQ |
697 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
698 | ||
c9180a57 | 699 | /* check if the old mount command had the same options */ |
0d90a7ec | 700 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
701 | if (!(sbsec->flags & flag) || |
702 | (old_sid != new_sid)) | |
703 | return 1; | |
704 | ||
705 | /* check if we were passed the same options twice, | |
706 | * aka someone passed context=a,context=b | |
707 | */ | |
0d90a7ec DQ |
708 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
709 | if (mnt_flags & flag) | |
c9180a57 EP |
710 | return 1; |
711 | return 0; | |
712 | } | |
e0007529 | 713 | |
c9180a57 EP |
714 | /* |
715 | * Allow filesystems with binary mount data to explicitly set mount point | |
716 | * labeling information. | |
717 | */ | |
e0007529 | 718 | static int selinux_set_mnt_opts(struct super_block *sb, |
649f6e77 DQ |
719 | struct security_mnt_opts *opts, |
720 | unsigned long kern_flags, | |
721 | unsigned long *set_kern_flags) | |
c9180a57 | 722 | { |
275bb41e | 723 | const struct cred *cred = current_cred(); |
c9180a57 | 724 | int rc = 0, i; |
c9180a57 | 725 | struct superblock_security_struct *sbsec = sb->s_security; |
29b1deb2 | 726 | const char *name = sb->s_type->name; |
83da53c5 | 727 | struct dentry *root = sbsec->sb->s_root; |
2c97165b | 728 | struct inode_security_struct *root_isec; |
c9180a57 EP |
729 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
730 | u32 defcontext_sid = 0; | |
e0007529 EP |
731 | char **mount_options = opts->mnt_opts; |
732 | int *flags = opts->mnt_opts_flags; | |
733 | int num_opts = opts->num_mnt_opts; | |
c9180a57 EP |
734 | |
735 | mutex_lock(&sbsec->lock); | |
736 | ||
aa8e712c | 737 | if (!selinux_state.initialized) { |
c9180a57 EP |
738 | if (!num_opts) { |
739 | /* Defer initialization until selinux_complete_init, | |
740 | after the initial policy is loaded and the security | |
741 | server is ready to handle calls. */ | |
c9180a57 EP |
742 | goto out; |
743 | } | |
744 | rc = -EINVAL; | |
744ba35e EP |
745 | printk(KERN_WARNING "SELinux: Unable to set superblock options " |
746 | "before the security server is initialized\n"); | |
1da177e4 | 747 | goto out; |
c9180a57 | 748 | } |
649f6e77 DQ |
749 | if (kern_flags && !set_kern_flags) { |
750 | /* Specifying internal flags without providing a place to | |
751 | * place the results is not allowed */ | |
752 | rc = -EINVAL; | |
753 | goto out; | |
754 | } | |
1da177e4 | 755 | |
e0007529 EP |
756 | /* |
757 | * Binary mount data FS will come through this function twice. Once | |
758 | * from an explicit call and once from the generic calls from the vfs. | |
759 | * Since the generic VFS calls will not contain any security mount data | |
760 | * we need to skip the double mount verification. | |
761 | * | |
762 | * This does open a hole in which we will not notice if the first | |
763 | * mount using this sb set explict options and a second mount using | |
764 | * this sb does not set any security options. (The first options | |
765 | * will be used for both mounts) | |
766 | */ | |
0d90a7ec | 767 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
e0007529 | 768 | && (num_opts == 0)) |
f5269710 | 769 | goto out; |
e0007529 | 770 | |
2c97165b PM |
771 | root_isec = backing_inode_security_novalidate(root); |
772 | ||
c9180a57 EP |
773 | /* |
774 | * parse the mount options, check if they are valid sids. | |
775 | * also check if someone is trying to mount the same sb more | |
776 | * than once with different security options. | |
777 | */ | |
778 | for (i = 0; i < num_opts; i++) { | |
779 | u32 sid; | |
11689d47 | 780 | |
12f348b9 | 781 | if (flags[i] == SBLABEL_MNT) |
11689d47 | 782 | continue; |
aa8e712c SS |
783 | rc = security_context_str_to_sid(&selinux_state, |
784 | mount_options[i], &sid, | |
785 | GFP_KERNEL); | |
1da177e4 | 786 | if (rc) { |
44be2f65 | 787 | printk(KERN_WARNING "SELinux: security_context_str_to_sid" |
29b1deb2 LT |
788 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
789 | mount_options[i], sb->s_id, name, rc); | |
c9180a57 EP |
790 | goto out; |
791 | } | |
792 | switch (flags[i]) { | |
793 | case FSCONTEXT_MNT: | |
794 | fscontext_sid = sid; | |
795 | ||
796 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
797 | fscontext_sid)) | |
798 | goto out_double_mount; | |
799 | ||
800 | sbsec->flags |= FSCONTEXT_MNT; | |
801 | break; | |
802 | case CONTEXT_MNT: | |
803 | context_sid = sid; | |
804 | ||
805 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
806 | context_sid)) | |
807 | goto out_double_mount; | |
808 | ||
809 | sbsec->flags |= CONTEXT_MNT; | |
810 | break; | |
811 | case ROOTCONTEXT_MNT: | |
812 | rootcontext_sid = sid; | |
813 | ||
814 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
815 | rootcontext_sid)) | |
816 | goto out_double_mount; | |
817 | ||
818 | sbsec->flags |= ROOTCONTEXT_MNT; | |
819 | ||
820 | break; | |
821 | case DEFCONTEXT_MNT: | |
822 | defcontext_sid = sid; | |
823 | ||
824 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
825 | defcontext_sid)) | |
826 | goto out_double_mount; | |
827 | ||
828 | sbsec->flags |= DEFCONTEXT_MNT; | |
829 | ||
830 | break; | |
831 | default: | |
832 | rc = -EINVAL; | |
833 | goto out; | |
1da177e4 | 834 | } |
c9180a57 EP |
835 | } |
836 | ||
0d90a7ec | 837 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 838 | /* previously mounted with options, but not on this attempt? */ |
0d90a7ec | 839 | if ((sbsec->flags & SE_MNTMASK) && !num_opts) |
c9180a57 EP |
840 | goto out_double_mount; |
841 | rc = 0; | |
842 | goto out; | |
843 | } | |
844 | ||
089be43e | 845 | if (strcmp(sb->s_type->name, "proc") == 0) |
134509d5 SS |
846 | sbsec->flags |= SE_SBPROC | SE_SBGENFS; |
847 | ||
8e014720 | 848 | if (!strcmp(sb->s_type->name, "debugfs") || |
6a391183 | 849 | !strcmp(sb->s_type->name, "tracefs") || |
8e014720 | 850 | !strcmp(sb->s_type->name, "sysfs") || |
901ef845 AM |
851 | !strcmp(sb->s_type->name, "pstore") || |
852 | !strcmp(sb->s_type->name, "cgroup") || | |
853 | !strcmp(sb->s_type->name, "cgroup2")) | |
134509d5 | 854 | sbsec->flags |= SE_SBGENFS; |
c9180a57 | 855 | |
eb9ae686 DQ |
856 | if (!sbsec->behavior) { |
857 | /* | |
858 | * Determine the labeling behavior to use for this | |
859 | * filesystem type. | |
860 | */ | |
aa8e712c | 861 | rc = security_fs_use(&selinux_state, sb); |
eb9ae686 DQ |
862 | if (rc) { |
863 | printk(KERN_WARNING | |
864 | "%s: security_fs_use(%s) returned %d\n", | |
865 | __func__, sb->s_type->name, rc); | |
866 | goto out; | |
867 | } | |
c9180a57 | 868 | } |
aad82892 SF |
869 | |
870 | /* | |
01593d32 SS |
871 | * If this is a user namespace mount and the filesystem type is not |
872 | * explicitly whitelisted, then no contexts are allowed on the command | |
873 | * line and security labels must be ignored. | |
aad82892 | 874 | */ |
01593d32 SS |
875 | if (sb->s_user_ns != &init_user_ns && |
876 | strcmp(sb->s_type->name, "tmpfs") && | |
877 | strcmp(sb->s_type->name, "ramfs") && | |
878 | strcmp(sb->s_type->name, "devpts")) { | |
aad82892 SF |
879 | if (context_sid || fscontext_sid || rootcontext_sid || |
880 | defcontext_sid) { | |
881 | rc = -EACCES; | |
882 | goto out; | |
883 | } | |
884 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { | |
885 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; | |
aa8e712c SS |
886 | rc = security_transition_sid(&selinux_state, |
887 | current_sid(), | |
888 | current_sid(), | |
aad82892 SF |
889 | SECCLASS_FILE, NULL, |
890 | &sbsec->mntpoint_sid); | |
891 | if (rc) | |
892 | goto out; | |
893 | } | |
894 | goto out_set_opts; | |
895 | } | |
896 | ||
c9180a57 EP |
897 | /* sets the context of the superblock for the fs being mounted. */ |
898 | if (fscontext_sid) { | |
275bb41e | 899 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
1da177e4 | 900 | if (rc) |
c9180a57 | 901 | goto out; |
1da177e4 | 902 | |
c9180a57 | 903 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
904 | } |
905 | ||
906 | /* | |
907 | * Switch to using mount point labeling behavior. | |
908 | * sets the label used on all file below the mountpoint, and will set | |
909 | * the superblock context if not already set. | |
910 | */ | |
eb9ae686 DQ |
911 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { |
912 | sbsec->behavior = SECURITY_FS_USE_NATIVE; | |
913 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
914 | } | |
915 | ||
c9180a57 EP |
916 | if (context_sid) { |
917 | if (!fscontext_sid) { | |
275bb41e DH |
918 | rc = may_context_mount_sb_relabel(context_sid, sbsec, |
919 | cred); | |
b04ea3ce | 920 | if (rc) |
c9180a57 EP |
921 | goto out; |
922 | sbsec->sid = context_sid; | |
b04ea3ce | 923 | } else { |
275bb41e DH |
924 | rc = may_context_mount_inode_relabel(context_sid, sbsec, |
925 | cred); | |
b04ea3ce | 926 | if (rc) |
c9180a57 | 927 | goto out; |
b04ea3ce | 928 | } |
c9180a57 EP |
929 | if (!rootcontext_sid) |
930 | rootcontext_sid = context_sid; | |
1da177e4 | 931 | |
c9180a57 | 932 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 933 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
934 | } |
935 | ||
c9180a57 | 936 | if (rootcontext_sid) { |
275bb41e DH |
937 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
938 | cred); | |
0808925e | 939 | if (rc) |
c9180a57 | 940 | goto out; |
0808925e | 941 | |
c9180a57 | 942 | root_isec->sid = rootcontext_sid; |
6f3be9f5 | 943 | root_isec->initialized = LABEL_INITIALIZED; |
0808925e EP |
944 | } |
945 | ||
c9180a57 | 946 | if (defcontext_sid) { |
eb9ae686 DQ |
947 | if (sbsec->behavior != SECURITY_FS_USE_XATTR && |
948 | sbsec->behavior != SECURITY_FS_USE_NATIVE) { | |
c9180a57 EP |
949 | rc = -EINVAL; |
950 | printk(KERN_WARNING "SELinux: defcontext option is " | |
951 | "invalid for this filesystem type\n"); | |
952 | goto out; | |
1da177e4 LT |
953 | } |
954 | ||
c9180a57 EP |
955 | if (defcontext_sid != sbsec->def_sid) { |
956 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
275bb41e | 957 | sbsec, cred); |
c9180a57 EP |
958 | if (rc) |
959 | goto out; | |
960 | } | |
1da177e4 | 961 | |
c9180a57 | 962 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
963 | } |
964 | ||
aad82892 | 965 | out_set_opts: |
c9180a57 | 966 | rc = sb_finish_set_opts(sb); |
1da177e4 | 967 | out: |
c9180a57 | 968 | mutex_unlock(&sbsec->lock); |
1da177e4 | 969 | return rc; |
c9180a57 EP |
970 | out_double_mount: |
971 | rc = -EINVAL; | |
972 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " | |
29b1deb2 | 973 | "security settings for (dev %s, type %s)\n", sb->s_id, name); |
c9180a57 | 974 | goto out; |
1da177e4 LT |
975 | } |
976 | ||
094f7b69 JL |
977 | static int selinux_cmp_sb_context(const struct super_block *oldsb, |
978 | const struct super_block *newsb) | |
979 | { | |
980 | struct superblock_security_struct *old = oldsb->s_security; | |
981 | struct superblock_security_struct *new = newsb->s_security; | |
982 | char oldflags = old->flags & SE_MNTMASK; | |
983 | char newflags = new->flags & SE_MNTMASK; | |
984 | ||
985 | if (oldflags != newflags) | |
986 | goto mismatch; | |
987 | if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) | |
988 | goto mismatch; | |
989 | if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) | |
990 | goto mismatch; | |
991 | if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) | |
992 | goto mismatch; | |
993 | if (oldflags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
994 | struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); |
995 | struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); | |
094f7b69 JL |
996 | if (oldroot->sid != newroot->sid) |
997 | goto mismatch; | |
998 | } | |
999 | return 0; | |
1000 | mismatch: | |
1001 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " | |
1002 | "different security settings for (dev %s, " | |
1003 | "type %s)\n", newsb->s_id, newsb->s_type->name); | |
1004 | return -EBUSY; | |
1005 | } | |
1006 | ||
1007 | static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, | |
0b4d3452 SM |
1008 | struct super_block *newsb, |
1009 | unsigned long kern_flags, | |
1010 | unsigned long *set_kern_flags) | |
1da177e4 | 1011 | { |
0b4d3452 | 1012 | int rc = 0; |
c9180a57 EP |
1013 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
1014 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 1015 | |
c9180a57 EP |
1016 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
1017 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
1018 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 1019 | |
0f5e6420 EP |
1020 | /* |
1021 | * if the parent was able to be mounted it clearly had no special lsm | |
e8c26255 | 1022 | * mount options. thus we can safely deal with this superblock later |
0f5e6420 | 1023 | */ |
aa8e712c | 1024 | if (!selinux_state.initialized) |
094f7b69 | 1025 | return 0; |
c9180a57 | 1026 | |
0b4d3452 SM |
1027 | /* |
1028 | * Specifying internal flags without providing a place to | |
1029 | * place the results is not allowed. | |
1030 | */ | |
1031 | if (kern_flags && !set_kern_flags) | |
1032 | return -EINVAL; | |
1033 | ||
c9180a57 | 1034 | /* how can we clone if the old one wasn't set up?? */ |
0d90a7ec | 1035 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
c9180a57 | 1036 | |
094f7b69 | 1037 | /* if fs is reusing a sb, make sure that the contexts match */ |
0d90a7ec | 1038 | if (newsbsec->flags & SE_SBINITIALIZED) |
094f7b69 | 1039 | return selinux_cmp_sb_context(oldsb, newsb); |
5a552617 | 1040 | |
c9180a57 EP |
1041 | mutex_lock(&newsbsec->lock); |
1042 | ||
1043 | newsbsec->flags = oldsbsec->flags; | |
1044 | ||
1045 | newsbsec->sid = oldsbsec->sid; | |
1046 | newsbsec->def_sid = oldsbsec->def_sid; | |
1047 | newsbsec->behavior = oldsbsec->behavior; | |
1048 | ||
0b4d3452 SM |
1049 | if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && |
1050 | !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { | |
aa8e712c | 1051 | rc = security_fs_use(&selinux_state, newsb); |
0b4d3452 SM |
1052 | if (rc) |
1053 | goto out; | |
1054 | } | |
1055 | ||
1056 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { | |
1057 | newsbsec->behavior = SECURITY_FS_USE_NATIVE; | |
1058 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
1059 | } | |
1060 | ||
c9180a57 EP |
1061 | if (set_context) { |
1062 | u32 sid = oldsbsec->mntpoint_sid; | |
1063 | ||
1064 | if (!set_fscontext) | |
1065 | newsbsec->sid = sid; | |
1066 | if (!set_rootcontext) { | |
83da53c5 | 1067 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); |
c9180a57 EP |
1068 | newisec->sid = sid; |
1069 | } | |
1070 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 1071 | } |
c9180a57 | 1072 | if (set_rootcontext) { |
83da53c5 AG |
1073 | const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); |
1074 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); | |
1da177e4 | 1075 | |
c9180a57 | 1076 | newisec->sid = oldisec->sid; |
1da177e4 LT |
1077 | } |
1078 | ||
c9180a57 | 1079 | sb_finish_set_opts(newsb); |
0b4d3452 | 1080 | out: |
c9180a57 | 1081 | mutex_unlock(&newsbsec->lock); |
0b4d3452 | 1082 | return rc; |
c9180a57 EP |
1083 | } |
1084 | ||
2e1479d9 AB |
1085 | static int selinux_parse_opts_str(char *options, |
1086 | struct security_mnt_opts *opts) | |
c9180a57 | 1087 | { |
e0007529 | 1088 | char *p; |
c9180a57 EP |
1089 | char *context = NULL, *defcontext = NULL; |
1090 | char *fscontext = NULL, *rootcontext = NULL; | |
e0007529 | 1091 | int rc, num_mnt_opts = 0; |
1da177e4 | 1092 | |
e0007529 | 1093 | opts->num_mnt_opts = 0; |
1da177e4 | 1094 | |
c9180a57 EP |
1095 | /* Standard string-based options. */ |
1096 | while ((p = strsep(&options, "|")) != NULL) { | |
1097 | int token; | |
1098 | substring_t args[MAX_OPT_ARGS]; | |
1da177e4 | 1099 | |
c9180a57 EP |
1100 | if (!*p) |
1101 | continue; | |
1da177e4 | 1102 | |
c9180a57 | 1103 | token = match_token(p, tokens, args); |
1da177e4 | 1104 | |
c9180a57 EP |
1105 | switch (token) { |
1106 | case Opt_context: | |
1107 | if (context || defcontext) { | |
1108 | rc = -EINVAL; | |
1109 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1110 | goto out_err; | |
1111 | } | |
1112 | context = match_strdup(&args[0]); | |
1113 | if (!context) { | |
1114 | rc = -ENOMEM; | |
1115 | goto out_err; | |
1116 | } | |
1117 | break; | |
1118 | ||
1119 | case Opt_fscontext: | |
1120 | if (fscontext) { | |
1121 | rc = -EINVAL; | |
1122 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1123 | goto out_err; | |
1124 | } | |
1125 | fscontext = match_strdup(&args[0]); | |
1126 | if (!fscontext) { | |
1127 | rc = -ENOMEM; | |
1128 | goto out_err; | |
1129 | } | |
1130 | break; | |
1131 | ||
1132 | case Opt_rootcontext: | |
1133 | if (rootcontext) { | |
1134 | rc = -EINVAL; | |
1135 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1136 | goto out_err; | |
1137 | } | |
1138 | rootcontext = match_strdup(&args[0]); | |
1139 | if (!rootcontext) { | |
1140 | rc = -ENOMEM; | |
1141 | goto out_err; | |
1142 | } | |
1143 | break; | |
1144 | ||
1145 | case Opt_defcontext: | |
1146 | if (context || defcontext) { | |
1147 | rc = -EINVAL; | |
1148 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1149 | goto out_err; | |
1150 | } | |
1151 | defcontext = match_strdup(&args[0]); | |
1152 | if (!defcontext) { | |
1153 | rc = -ENOMEM; | |
1154 | goto out_err; | |
1155 | } | |
1156 | break; | |
11689d47 DQ |
1157 | case Opt_labelsupport: |
1158 | break; | |
c9180a57 EP |
1159 | default: |
1160 | rc = -EINVAL; | |
1161 | printk(KERN_WARNING "SELinux: unknown mount option\n"); | |
1162 | goto out_err; | |
1da177e4 | 1163 | |
1da177e4 | 1164 | } |
1da177e4 | 1165 | } |
c9180a57 | 1166 | |
e0007529 | 1167 | rc = -ENOMEM; |
8931c3bd | 1168 | opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL); |
e0007529 EP |
1169 | if (!opts->mnt_opts) |
1170 | goto out_err; | |
1171 | ||
8931c3bd TH |
1172 | opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), |
1173 | GFP_KERNEL); | |
023f108d | 1174 | if (!opts->mnt_opts_flags) |
e0007529 | 1175 | goto out_err; |
e0007529 | 1176 | |
c9180a57 | 1177 | if (fscontext) { |
e0007529 EP |
1178 | opts->mnt_opts[num_mnt_opts] = fscontext; |
1179 | opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; | |
c9180a57 EP |
1180 | } |
1181 | if (context) { | |
e0007529 EP |
1182 | opts->mnt_opts[num_mnt_opts] = context; |
1183 | opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; | |
c9180a57 EP |
1184 | } |
1185 | if (rootcontext) { | |
e0007529 EP |
1186 | opts->mnt_opts[num_mnt_opts] = rootcontext; |
1187 | opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; | |
c9180a57 EP |
1188 | } |
1189 | if (defcontext) { | |
e0007529 EP |
1190 | opts->mnt_opts[num_mnt_opts] = defcontext; |
1191 | opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
1192 | } |
1193 | ||
e0007529 EP |
1194 | opts->num_mnt_opts = num_mnt_opts; |
1195 | return 0; | |
1196 | ||
c9180a57 | 1197 | out_err: |
023f108d | 1198 | security_free_mnt_opts(opts); |
c9180a57 EP |
1199 | kfree(context); |
1200 | kfree(defcontext); | |
1201 | kfree(fscontext); | |
1202 | kfree(rootcontext); | |
1da177e4 LT |
1203 | return rc; |
1204 | } | |
e0007529 EP |
1205 | /* |
1206 | * string mount options parsing and call set the sbsec | |
1207 | */ | |
1208 | static int superblock_doinit(struct super_block *sb, void *data) | |
1209 | { | |
1210 | int rc = 0; | |
1211 | char *options = data; | |
1212 | struct security_mnt_opts opts; | |
1213 | ||
1214 | security_init_mnt_opts(&opts); | |
1215 | ||
1216 | if (!data) | |
1217 | goto out; | |
1218 | ||
1219 | BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); | |
1220 | ||
1221 | rc = selinux_parse_opts_str(options, &opts); | |
1222 | if (rc) | |
1223 | goto out_err; | |
1224 | ||
1225 | out: | |
649f6e77 | 1226 | rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); |
e0007529 EP |
1227 | |
1228 | out_err: | |
1229 | security_free_mnt_opts(&opts); | |
1230 | return rc; | |
1231 | } | |
1da177e4 | 1232 | |
3583a711 AB |
1233 | static void selinux_write_opts(struct seq_file *m, |
1234 | struct security_mnt_opts *opts) | |
2069f457 EP |
1235 | { |
1236 | int i; | |
1237 | char *prefix; | |
1238 | ||
1239 | for (i = 0; i < opts->num_mnt_opts; i++) { | |
11689d47 DQ |
1240 | char *has_comma; |
1241 | ||
1242 | if (opts->mnt_opts[i]) | |
1243 | has_comma = strchr(opts->mnt_opts[i], ','); | |
1244 | else | |
1245 | has_comma = NULL; | |
2069f457 EP |
1246 | |
1247 | switch (opts->mnt_opts_flags[i]) { | |
1248 | case CONTEXT_MNT: | |
1249 | prefix = CONTEXT_STR; | |
1250 | break; | |
1251 | case FSCONTEXT_MNT: | |
1252 | prefix = FSCONTEXT_STR; | |
1253 | break; | |
1254 | case ROOTCONTEXT_MNT: | |
1255 | prefix = ROOTCONTEXT_STR; | |
1256 | break; | |
1257 | case DEFCONTEXT_MNT: | |
1258 | prefix = DEFCONTEXT_STR; | |
1259 | break; | |
12f348b9 | 1260 | case SBLABEL_MNT: |
11689d47 DQ |
1261 | seq_putc(m, ','); |
1262 | seq_puts(m, LABELSUPP_STR); | |
1263 | continue; | |
2069f457 EP |
1264 | default: |
1265 | BUG(); | |
a35c6c83 | 1266 | return; |
2069f457 EP |
1267 | }; |
1268 | /* we need a comma before each option */ | |
1269 | seq_putc(m, ','); | |
1270 | seq_puts(m, prefix); | |
1271 | if (has_comma) | |
1272 | seq_putc(m, '\"'); | |
a068acf2 | 1273 | seq_escape(m, opts->mnt_opts[i], "\"\n\\"); |
2069f457 EP |
1274 | if (has_comma) |
1275 | seq_putc(m, '\"'); | |
1276 | } | |
1277 | } | |
1278 | ||
1279 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1280 | { | |
1281 | struct security_mnt_opts opts; | |
1282 | int rc; | |
1283 | ||
1284 | rc = selinux_get_mnt_opts(sb, &opts); | |
383795c2 EP |
1285 | if (rc) { |
1286 | /* before policy load we may get EINVAL, don't show anything */ | |
1287 | if (rc == -EINVAL) | |
1288 | rc = 0; | |
2069f457 | 1289 | return rc; |
383795c2 | 1290 | } |
2069f457 EP |
1291 | |
1292 | selinux_write_opts(m, &opts); | |
1293 | ||
1294 | security_free_mnt_opts(&opts); | |
1295 | ||
1296 | return rc; | |
1297 | } | |
1298 | ||
1da177e4 LT |
1299 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1300 | { | |
1301 | switch (mode & S_IFMT) { | |
1302 | case S_IFSOCK: | |
1303 | return SECCLASS_SOCK_FILE; | |
1304 | case S_IFLNK: | |
1305 | return SECCLASS_LNK_FILE; | |
1306 | case S_IFREG: | |
1307 | return SECCLASS_FILE; | |
1308 | case S_IFBLK: | |
1309 | return SECCLASS_BLK_FILE; | |
1310 | case S_IFDIR: | |
1311 | return SECCLASS_DIR; | |
1312 | case S_IFCHR: | |
1313 | return SECCLASS_CHR_FILE; | |
1314 | case S_IFIFO: | |
1315 | return SECCLASS_FIFO_FILE; | |
1316 | ||
1317 | } | |
1318 | ||
1319 | return SECCLASS_FILE; | |
1320 | } | |
1321 | ||
13402580 JM |
1322 | static inline int default_protocol_stream(int protocol) |
1323 | { | |
1324 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1325 | } | |
1326 | ||
1327 | static inline int default_protocol_dgram(int protocol) | |
1328 | { | |
1329 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1330 | } | |
1331 | ||
1da177e4 LT |
1332 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1333 | { | |
aa8e712c | 1334 | int extsockclass = selinux_policycap_extsockclass(); |
da69a530 | 1335 | |
1da177e4 LT |
1336 | switch (family) { |
1337 | case PF_UNIX: | |
1338 | switch (type) { | |
1339 | case SOCK_STREAM: | |
1340 | case SOCK_SEQPACKET: | |
1341 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1342 | case SOCK_DGRAM: | |
2a764b52 | 1343 | case SOCK_RAW: |
1da177e4 LT |
1344 | return SECCLASS_UNIX_DGRAM_SOCKET; |
1345 | } | |
1346 | break; | |
1347 | case PF_INET: | |
1348 | case PF_INET6: | |
1349 | switch (type) { | |
1350 | case SOCK_STREAM: | |
da69a530 | 1351 | case SOCK_SEQPACKET: |
13402580 JM |
1352 | if (default_protocol_stream(protocol)) |
1353 | return SECCLASS_TCP_SOCKET; | |
da69a530 SS |
1354 | else if (extsockclass && protocol == IPPROTO_SCTP) |
1355 | return SECCLASS_SCTP_SOCKET; | |
13402580 JM |
1356 | else |
1357 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1358 | case SOCK_DGRAM: |
13402580 JM |
1359 | if (default_protocol_dgram(protocol)) |
1360 | return SECCLASS_UDP_SOCKET; | |
ef37979a SS |
1361 | else if (extsockclass && (protocol == IPPROTO_ICMP || |
1362 | protocol == IPPROTO_ICMPV6)) | |
da69a530 | 1363 | return SECCLASS_ICMP_SOCKET; |
13402580 JM |
1364 | else |
1365 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1366 | case SOCK_DCCP: |
1367 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1368 | default: |
1da177e4 LT |
1369 | return SECCLASS_RAWIP_SOCKET; |
1370 | } | |
1371 | break; | |
1372 | case PF_NETLINK: | |
1373 | switch (protocol) { | |
1374 | case NETLINK_ROUTE: | |
1375 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
7f1fb60c | 1376 | case NETLINK_SOCK_DIAG: |
1da177e4 LT |
1377 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1378 | case NETLINK_NFLOG: | |
1379 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1380 | case NETLINK_XFRM: | |
1381 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1382 | case NETLINK_SELINUX: | |
1383 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
6c6d2e9b SS |
1384 | case NETLINK_ISCSI: |
1385 | return SECCLASS_NETLINK_ISCSI_SOCKET; | |
1da177e4 LT |
1386 | case NETLINK_AUDIT: |
1387 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
6c6d2e9b SS |
1388 | case NETLINK_FIB_LOOKUP: |
1389 | return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; | |
1390 | case NETLINK_CONNECTOR: | |
1391 | return SECCLASS_NETLINK_CONNECTOR_SOCKET; | |
1392 | case NETLINK_NETFILTER: | |
1393 | return SECCLASS_NETLINK_NETFILTER_SOCKET; | |
1da177e4 LT |
1394 | case NETLINK_DNRTMSG: |
1395 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1396 | case NETLINK_KOBJECT_UEVENT: |
1397 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
6c6d2e9b SS |
1398 | case NETLINK_GENERIC: |
1399 | return SECCLASS_NETLINK_GENERIC_SOCKET; | |
1400 | case NETLINK_SCSITRANSPORT: | |
1401 | return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; | |
1402 | case NETLINK_RDMA: | |
1403 | return SECCLASS_NETLINK_RDMA_SOCKET; | |
1404 | case NETLINK_CRYPTO: | |
1405 | return SECCLASS_NETLINK_CRYPTO_SOCKET; | |
1da177e4 LT |
1406 | default: |
1407 | return SECCLASS_NETLINK_SOCKET; | |
1408 | } | |
1409 | case PF_PACKET: | |
1410 | return SECCLASS_PACKET_SOCKET; | |
1411 | case PF_KEY: | |
1412 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1413 | case PF_APPLETALK: |
1414 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1415 | } |
1416 | ||
da69a530 SS |
1417 | if (extsockclass) { |
1418 | switch (family) { | |
1419 | case PF_AX25: | |
1420 | return SECCLASS_AX25_SOCKET; | |
1421 | case PF_IPX: | |
1422 | return SECCLASS_IPX_SOCKET; | |
1423 | case PF_NETROM: | |
1424 | return SECCLASS_NETROM_SOCKET; | |
da69a530 SS |
1425 | case PF_ATMPVC: |
1426 | return SECCLASS_ATMPVC_SOCKET; | |
1427 | case PF_X25: | |
1428 | return SECCLASS_X25_SOCKET; | |
1429 | case PF_ROSE: | |
1430 | return SECCLASS_ROSE_SOCKET; | |
1431 | case PF_DECnet: | |
1432 | return SECCLASS_DECNET_SOCKET; | |
1433 | case PF_ATMSVC: | |
1434 | return SECCLASS_ATMSVC_SOCKET; | |
1435 | case PF_RDS: | |
1436 | return SECCLASS_RDS_SOCKET; | |
1437 | case PF_IRDA: | |
1438 | return SECCLASS_IRDA_SOCKET; | |
1439 | case PF_PPPOX: | |
1440 | return SECCLASS_PPPOX_SOCKET; | |
1441 | case PF_LLC: | |
1442 | return SECCLASS_LLC_SOCKET; | |
da69a530 SS |
1443 | case PF_CAN: |
1444 | return SECCLASS_CAN_SOCKET; | |
1445 | case PF_TIPC: | |
1446 | return SECCLASS_TIPC_SOCKET; | |
1447 | case PF_BLUETOOTH: | |
1448 | return SECCLASS_BLUETOOTH_SOCKET; | |
1449 | case PF_IUCV: | |
1450 | return SECCLASS_IUCV_SOCKET; | |
1451 | case PF_RXRPC: | |
1452 | return SECCLASS_RXRPC_SOCKET; | |
1453 | case PF_ISDN: | |
1454 | return SECCLASS_ISDN_SOCKET; | |
1455 | case PF_PHONET: | |
1456 | return SECCLASS_PHONET_SOCKET; | |
1457 | case PF_IEEE802154: | |
1458 | return SECCLASS_IEEE802154_SOCKET; | |
1459 | case PF_CAIF: | |
1460 | return SECCLASS_CAIF_SOCKET; | |
1461 | case PF_ALG: | |
1462 | return SECCLASS_ALG_SOCKET; | |
1463 | case PF_NFC: | |
1464 | return SECCLASS_NFC_SOCKET; | |
1465 | case PF_VSOCK: | |
1466 | return SECCLASS_VSOCK_SOCKET; | |
1467 | case PF_KCM: | |
1468 | return SECCLASS_KCM_SOCKET; | |
1469 | case PF_QIPCRTR: | |
1470 | return SECCLASS_QIPCRTR_SOCKET; | |
3051bf36 LT |
1471 | case PF_SMC: |
1472 | return SECCLASS_SMC_SOCKET; | |
68e8b849 BT |
1473 | case PF_XDP: |
1474 | return SECCLASS_XDP_SOCKET; | |
1475 | #if PF_MAX > 45 | |
da69a530 SS |
1476 | #error New address family defined, please update this function. |
1477 | #endif | |
1478 | } | |
1479 | } | |
1480 | ||
1da177e4 LT |
1481 | return SECCLASS_SOCKET; |
1482 | } | |
1483 | ||
134509d5 SS |
1484 | static int selinux_genfs_get_sid(struct dentry *dentry, |
1485 | u16 tclass, | |
1486 | u16 flags, | |
1487 | u32 *sid) | |
1da177e4 | 1488 | { |
8e6c9693 | 1489 | int rc; |
fc64005c | 1490 | struct super_block *sb = dentry->d_sb; |
8e6c9693 | 1491 | char *buffer, *path; |
1da177e4 | 1492 | |
828dfe1d | 1493 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1494 | if (!buffer) |
1495 | return -ENOMEM; | |
1496 | ||
8e6c9693 LAG |
1497 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1498 | if (IS_ERR(path)) | |
1499 | rc = PTR_ERR(path); | |
1500 | else { | |
134509d5 SS |
1501 | if (flags & SE_SBPROC) { |
1502 | /* each process gets a /proc/PID/ entry. Strip off the | |
1503 | * PID part to get a valid selinux labeling. | |
1504 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1505 | while (path[1] >= '0' && path[1] <= '9') { | |
1506 | path[1] = '/'; | |
1507 | path++; | |
1508 | } | |
8e6c9693 | 1509 | } |
aa8e712c SS |
1510 | rc = security_genfs_sid(&selinux_state, sb->s_type->name, |
1511 | path, tclass, sid); | |
1da177e4 | 1512 | } |
1da177e4 LT |
1513 | free_page((unsigned long)buffer); |
1514 | return rc; | |
1515 | } | |
1da177e4 LT |
1516 | |
1517 | /* The inode's security attributes must be initialized before first use. */ | |
1518 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1519 | { | |
1520 | struct superblock_security_struct *sbsec = NULL; | |
1521 | struct inode_security_struct *isec = inode->i_security; | |
9287aed2 AG |
1522 | u32 task_sid, sid = 0; |
1523 | u16 sclass; | |
1da177e4 LT |
1524 | struct dentry *dentry; |
1525 | #define INITCONTEXTLEN 255 | |
1526 | char *context = NULL; | |
1527 | unsigned len = 0; | |
1528 | int rc = 0; | |
1da177e4 | 1529 | |
6f3be9f5 | 1530 | if (isec->initialized == LABEL_INITIALIZED) |
13457d07 | 1531 | return 0; |
1da177e4 | 1532 | |
9287aed2 | 1533 | spin_lock(&isec->lock); |
6f3be9f5 | 1534 | if (isec->initialized == LABEL_INITIALIZED) |
23970741 | 1535 | goto out_unlock; |
1da177e4 | 1536 | |
13457d07 AG |
1537 | if (isec->sclass == SECCLASS_FILE) |
1538 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1539 | ||
1da177e4 | 1540 | sbsec = inode->i_sb->s_security; |
0d90a7ec | 1541 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1542 | /* Defer initialization until selinux_complete_init, |
1543 | after the initial policy is loaded and the security | |
1544 | server is ready to handle calls. */ | |
1545 | spin_lock(&sbsec->isec_lock); | |
1546 | if (list_empty(&isec->list)) | |
1547 | list_add(&isec->list, &sbsec->isec_head); | |
1548 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1549 | goto out_unlock; |
1da177e4 LT |
1550 | } |
1551 | ||
9287aed2 AG |
1552 | sclass = isec->sclass; |
1553 | task_sid = isec->task_sid; | |
1554 | sid = isec->sid; | |
1555 | isec->initialized = LABEL_PENDING; | |
1556 | spin_unlock(&isec->lock); | |
1557 | ||
1da177e4 | 1558 | switch (sbsec->behavior) { |
eb9ae686 DQ |
1559 | case SECURITY_FS_USE_NATIVE: |
1560 | break; | |
1da177e4 | 1561 | case SECURITY_FS_USE_XATTR: |
5d6c3191 | 1562 | if (!(inode->i_opflags & IOP_XATTR)) { |
9287aed2 | 1563 | sid = sbsec->def_sid; |
1da177e4 LT |
1564 | break; |
1565 | } | |
1da177e4 LT |
1566 | /* Need a dentry, since the xattr API requires one. |
1567 | Life would be simpler if we could just pass the inode. */ | |
1568 | if (opt_dentry) { | |
1569 | /* Called from d_instantiate or d_splice_alias. */ | |
1570 | dentry = dget(opt_dentry); | |
1571 | } else { | |
b127125d AV |
1572 | /* |
1573 | * Called from selinux_complete_init, try to find a dentry. | |
1574 | * Some filesystems really want a connected one, so try | |
1575 | * that first. We could split SECURITY_FS_USE_XATTR in | |
1576 | * two, depending upon that... | |
1577 | */ | |
1da177e4 | 1578 | dentry = d_find_alias(inode); |
b127125d AV |
1579 | if (!dentry) |
1580 | dentry = d_find_any_alias(inode); | |
1da177e4 LT |
1581 | } |
1582 | if (!dentry) { | |
df7f54c0 EP |
1583 | /* |
1584 | * this is can be hit on boot when a file is accessed | |
1585 | * before the policy is loaded. When we load policy we | |
1586 | * may find inodes that have no dentry on the | |
1587 | * sbsec->isec_head list. No reason to complain as these | |
1588 | * will get fixed up the next time we go through | |
1589 | * inode_doinit with a dentry, before these inodes could | |
1590 | * be used again by userspace. | |
1591 | */ | |
9287aed2 | 1592 | goto out; |
1da177e4 LT |
1593 | } |
1594 | ||
1595 | len = INITCONTEXTLEN; | |
4cb912f1 | 1596 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1597 | if (!context) { |
1598 | rc = -ENOMEM; | |
1599 | dput(dentry); | |
9287aed2 | 1600 | goto out; |
1da177e4 | 1601 | } |
4cb912f1 | 1602 | context[len] = '\0'; |
5d6c3191 | 1603 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); |
1da177e4 | 1604 | if (rc == -ERANGE) { |
314dabb8 JM |
1605 | kfree(context); |
1606 | ||
1da177e4 | 1607 | /* Need a larger buffer. Query for the right size. */ |
5d6c3191 | 1608 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); |
1da177e4 LT |
1609 | if (rc < 0) { |
1610 | dput(dentry); | |
9287aed2 | 1611 | goto out; |
1da177e4 | 1612 | } |
1da177e4 | 1613 | len = rc; |
4cb912f1 | 1614 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1615 | if (!context) { |
1616 | rc = -ENOMEM; | |
1617 | dput(dentry); | |
9287aed2 | 1618 | goto out; |
1da177e4 | 1619 | } |
4cb912f1 | 1620 | context[len] = '\0'; |
5d6c3191 | 1621 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); |
1da177e4 LT |
1622 | } |
1623 | dput(dentry); | |
1624 | if (rc < 0) { | |
1625 | if (rc != -ENODATA) { | |
744ba35e | 1626 | printk(KERN_WARNING "SELinux: %s: getxattr returned " |
dd6f953a | 1627 | "%d for dev=%s ino=%ld\n", __func__, |
1da177e4 LT |
1628 | -rc, inode->i_sb->s_id, inode->i_ino); |
1629 | kfree(context); | |
9287aed2 | 1630 | goto out; |
1da177e4 LT |
1631 | } |
1632 | /* Map ENODATA to the default file SID */ | |
1633 | sid = sbsec->def_sid; | |
1634 | rc = 0; | |
1635 | } else { | |
aa8e712c SS |
1636 | rc = security_context_to_sid_default(&selinux_state, |
1637 | context, rc, &sid, | |
869ab514 SS |
1638 | sbsec->def_sid, |
1639 | GFP_NOFS); | |
1da177e4 | 1640 | if (rc) { |
4ba0a8ad EP |
1641 | char *dev = inode->i_sb->s_id; |
1642 | unsigned long ino = inode->i_ino; | |
1643 | ||
1644 | if (rc == -EINVAL) { | |
1645 | if (printk_ratelimit()) | |
1646 | printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " | |
1647 | "context=%s. This indicates you may need to relabel the inode or the " | |
1648 | "filesystem in question.\n", ino, dev, context); | |
1649 | } else { | |
1650 | printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " | |
1651 | "returned %d for dev=%s ino=%ld\n", | |
1652 | __func__, context, -rc, dev, ino); | |
1653 | } | |
1da177e4 LT |
1654 | kfree(context); |
1655 | /* Leave with the unlabeled SID */ | |
1656 | rc = 0; | |
1657 | break; | |
1658 | } | |
1659 | } | |
1660 | kfree(context); | |
1da177e4 LT |
1661 | break; |
1662 | case SECURITY_FS_USE_TASK: | |
9287aed2 | 1663 | sid = task_sid; |
1da177e4 LT |
1664 | break; |
1665 | case SECURITY_FS_USE_TRANS: | |
1666 | /* Default to the fs SID. */ | |
9287aed2 | 1667 | sid = sbsec->sid; |
1da177e4 LT |
1668 | |
1669 | /* Try to obtain a transition SID. */ | |
aa8e712c SS |
1670 | rc = security_transition_sid(&selinux_state, task_sid, sid, |
1671 | sclass, NULL, &sid); | |
1da177e4 | 1672 | if (rc) |
9287aed2 | 1673 | goto out; |
1da177e4 | 1674 | break; |
c312feb2 | 1675 | case SECURITY_FS_USE_MNTPOINT: |
9287aed2 | 1676 | sid = sbsec->mntpoint_sid; |
c312feb2 | 1677 | break; |
1da177e4 | 1678 | default: |
c312feb2 | 1679 | /* Default to the fs superblock SID. */ |
9287aed2 | 1680 | sid = sbsec->sid; |
1da177e4 | 1681 | |
134509d5 | 1682 | if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) { |
f64410ec PM |
1683 | /* We must have a dentry to determine the label on |
1684 | * procfs inodes */ | |
b127125d | 1685 | if (opt_dentry) { |
f64410ec PM |
1686 | /* Called from d_instantiate or |
1687 | * d_splice_alias. */ | |
1688 | dentry = dget(opt_dentry); | |
b127125d | 1689 | } else { |
f64410ec | 1690 | /* Called from selinux_complete_init, try to |
b127125d AV |
1691 | * find a dentry. Some filesystems really want |
1692 | * a connected one, so try that first. | |
1693 | */ | |
f64410ec | 1694 | dentry = d_find_alias(inode); |
b127125d AV |
1695 | if (!dentry) |
1696 | dentry = d_find_any_alias(inode); | |
1697 | } | |
f64410ec PM |
1698 | /* |
1699 | * This can be hit on boot when a file is accessed | |
1700 | * before the policy is loaded. When we load policy we | |
1701 | * may find inodes that have no dentry on the | |
1702 | * sbsec->isec_head list. No reason to complain as | |
1703 | * these will get fixed up the next time we go through | |
1704 | * inode_doinit() with a dentry, before these inodes | |
1705 | * could be used again by userspace. | |
1706 | */ | |
1707 | if (!dentry) | |
9287aed2 AG |
1708 | goto out; |
1709 | rc = selinux_genfs_get_sid(dentry, sclass, | |
134509d5 | 1710 | sbsec->flags, &sid); |
f64410ec PM |
1711 | dput(dentry); |
1712 | if (rc) | |
9287aed2 | 1713 | goto out; |
1da177e4 LT |
1714 | } |
1715 | break; | |
1716 | } | |
1717 | ||
9287aed2 AG |
1718 | out: |
1719 | spin_lock(&isec->lock); | |
1720 | if (isec->initialized == LABEL_PENDING) { | |
1721 | if (!sid || rc) { | |
1722 | isec->initialized = LABEL_INVALID; | |
1723 | goto out_unlock; | |
1724 | } | |
1725 | ||
1726 | isec->initialized = LABEL_INITIALIZED; | |
1727 | isec->sid = sid; | |
1728 | } | |
1da177e4 | 1729 | |
23970741 | 1730 | out_unlock: |
9287aed2 | 1731 | spin_unlock(&isec->lock); |
1da177e4 LT |
1732 | return rc; |
1733 | } | |
1734 | ||
1735 | /* Convert a Linux signal to an access vector. */ | |
1736 | static inline u32 signal_to_av(int sig) | |
1737 | { | |
1738 | u32 perm = 0; | |
1739 | ||
1740 | switch (sig) { | |
1741 | case SIGCHLD: | |
1742 | /* Commonly granted from child to parent. */ | |
1743 | perm = PROCESS__SIGCHLD; | |
1744 | break; | |
1745 | case SIGKILL: | |
1746 | /* Cannot be caught or ignored */ | |
1747 | perm = PROCESS__SIGKILL; | |
1748 | break; | |
1749 | case SIGSTOP: | |
1750 | /* Cannot be caught or ignored */ | |
1751 | perm = PROCESS__SIGSTOP; | |
1752 | break; | |
1753 | default: | |
1754 | /* All other signals. */ | |
1755 | perm = PROCESS__SIGNAL; | |
1756 | break; | |
1757 | } | |
1758 | ||
1759 | return perm; | |
1760 | } | |
1761 | ||
b68e418c SS |
1762 | #if CAP_LAST_CAP > 63 |
1763 | #error Fix SELinux to handle capabilities > 63. | |
1764 | #endif | |
1765 | ||
1da177e4 | 1766 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1767 | static int cred_has_capability(const struct cred *cred, |
8e4ff6f2 | 1768 | int cap, int audit, bool initns) |
1da177e4 | 1769 | { |
2bf49690 | 1770 | struct common_audit_data ad; |
06112163 | 1771 | struct av_decision avd; |
b68e418c | 1772 | u16 sclass; |
3699c53c | 1773 | u32 sid = cred_sid(cred); |
b68e418c | 1774 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1775 | int rc; |
1da177e4 | 1776 | |
50c205f5 | 1777 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1778 | ad.u.cap = cap; |
1779 | ||
b68e418c SS |
1780 | switch (CAP_TO_INDEX(cap)) { |
1781 | case 0: | |
8e4ff6f2 | 1782 | sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; |
b68e418c SS |
1783 | break; |
1784 | case 1: | |
8e4ff6f2 | 1785 | sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; |
b68e418c SS |
1786 | break; |
1787 | default: | |
1788 | printk(KERN_ERR | |
1789 | "SELinux: out of range capability %d\n", cap); | |
1790 | BUG(); | |
a35c6c83 | 1791 | return -EINVAL; |
b68e418c | 1792 | } |
06112163 | 1793 | |
6b6bc620 SS |
1794 | rc = avc_has_perm_noaudit(&selinux_state, |
1795 | sid, sid, sclass, av, 0, &avd); | |
9ade0cf4 | 1796 | if (audit == SECURITY_CAP_AUDIT) { |
6b6bc620 SS |
1797 | int rc2 = avc_audit(&selinux_state, |
1798 | sid, sid, sclass, av, &avd, rc, &ad, 0); | |
9ade0cf4 EP |
1799 | if (rc2) |
1800 | return rc2; | |
1801 | } | |
06112163 | 1802 | return rc; |
1da177e4 LT |
1803 | } |
1804 | ||
1da177e4 LT |
1805 | /* Check whether a task has a particular permission to an inode. |
1806 | The 'adp' parameter is optional and allows other audit | |
1807 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1808 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1809 | struct inode *inode, |
1810 | u32 perms, | |
19e49834 | 1811 | struct common_audit_data *adp) |
1da177e4 | 1812 | { |
1da177e4 | 1813 | struct inode_security_struct *isec; |
275bb41e | 1814 | u32 sid; |
1da177e4 | 1815 | |
e0e81739 DH |
1816 | validate_creds(cred); |
1817 | ||
828dfe1d | 1818 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1819 | return 0; |
1820 | ||
88e67f3b | 1821 | sid = cred_sid(cred); |
1da177e4 LT |
1822 | isec = inode->i_security; |
1823 | ||
6b6bc620 SS |
1824 | return avc_has_perm(&selinux_state, |
1825 | sid, isec->sid, isec->sclass, perms, adp); | |
1da177e4 LT |
1826 | } |
1827 | ||
1828 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1829 | the dentry to help the auditing code to more easily generate the | |
1830 | pathname if needed. */ | |
88e67f3b | 1831 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1832 | struct dentry *dentry, |
1833 | u32 av) | |
1834 | { | |
c6f493d6 | 1835 | struct inode *inode = d_backing_inode(dentry); |
2bf49690 | 1836 | struct common_audit_data ad; |
88e67f3b | 1837 | |
50c205f5 | 1838 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1839 | ad.u.dentry = dentry; |
5d226df4 | 1840 | __inode_security_revalidate(inode, dentry, true); |
19e49834 | 1841 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1842 | } |
1843 | ||
1844 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1845 | the path to help the auditing code to more easily generate the | |
1846 | pathname if needed. */ | |
1847 | static inline int path_has_perm(const struct cred *cred, | |
3f7036a0 | 1848 | const struct path *path, |
2875fa00 EP |
1849 | u32 av) |
1850 | { | |
c6f493d6 | 1851 | struct inode *inode = d_backing_inode(path->dentry); |
2875fa00 EP |
1852 | struct common_audit_data ad; |
1853 | ||
50c205f5 | 1854 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1855 | ad.u.path = *path; |
5d226df4 | 1856 | __inode_security_revalidate(inode, path->dentry, true); |
19e49834 | 1857 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1858 | } |
1859 | ||
13f8e981 DH |
1860 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1861 | static inline int file_path_has_perm(const struct cred *cred, | |
1862 | struct file *file, | |
1863 | u32 av) | |
1864 | { | |
1865 | struct common_audit_data ad; | |
1866 | ||
43af5de7 VG |
1867 | ad.type = LSM_AUDIT_DATA_FILE; |
1868 | ad.u.file = file; | |
19e49834 | 1869 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1870 | } |
1871 | ||
f66e448c CF |
1872 | #ifdef CONFIG_BPF_SYSCALL |
1873 | static int bpf_fd_pass(struct file *file, u32 sid); | |
1874 | #endif | |
1875 | ||
1da177e4 LT |
1876 | /* Check whether a task can use an open file descriptor to |
1877 | access an inode in a given way. Check access to the | |
1878 | descriptor itself, and then use dentry_has_perm to | |
1879 | check a particular permission to the file. | |
1880 | Access to the descriptor is implicitly granted if it | |
1881 | has the same SID as the process. If av is zero, then | |
1882 | access to the file is not checked, e.g. for cases | |
1883 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1884 | static int file_has_perm(const struct cred *cred, |
1885 | struct file *file, | |
1886 | u32 av) | |
1da177e4 | 1887 | { |
1da177e4 | 1888 | struct file_security_struct *fsec = file->f_security; |
496ad9aa | 1889 | struct inode *inode = file_inode(file); |
2bf49690 | 1890 | struct common_audit_data ad; |
88e67f3b | 1891 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1892 | int rc; |
1893 | ||
43af5de7 VG |
1894 | ad.type = LSM_AUDIT_DATA_FILE; |
1895 | ad.u.file = file; | |
1da177e4 | 1896 | |
275bb41e | 1897 | if (sid != fsec->sid) { |
6b6bc620 SS |
1898 | rc = avc_has_perm(&selinux_state, |
1899 | sid, fsec->sid, | |
1da177e4 LT |
1900 | SECCLASS_FD, |
1901 | FD__USE, | |
1902 | &ad); | |
1903 | if (rc) | |
88e67f3b | 1904 | goto out; |
1da177e4 LT |
1905 | } |
1906 | ||
f66e448c CF |
1907 | #ifdef CONFIG_BPF_SYSCALL |
1908 | rc = bpf_fd_pass(file, cred_sid(cred)); | |
1909 | if (rc) | |
1910 | return rc; | |
1911 | #endif | |
1912 | ||
1da177e4 | 1913 | /* av is zero if only checking access to the descriptor. */ |
88e67f3b | 1914 | rc = 0; |
1da177e4 | 1915 | if (av) |
19e49834 | 1916 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1917 | |
88e67f3b DH |
1918 | out: |
1919 | return rc; | |
1da177e4 LT |
1920 | } |
1921 | ||
c3c188b2 DH |
1922 | /* |
1923 | * Determine the label for an inode that might be unioned. | |
1924 | */ | |
c957f6df VG |
1925 | static int |
1926 | selinux_determine_inode_label(const struct task_security_struct *tsec, | |
1927 | struct inode *dir, | |
1928 | const struct qstr *name, u16 tclass, | |
1929 | u32 *_new_isid) | |
c3c188b2 DH |
1930 | { |
1931 | const struct superblock_security_struct *sbsec = dir->i_sb->s_security; | |
c3c188b2 DH |
1932 | |
1933 | if ((sbsec->flags & SE_SBINITIALIZED) && | |
1934 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { | |
1935 | *_new_isid = sbsec->mntpoint_sid; | |
1936 | } else if ((sbsec->flags & SBLABEL_MNT) && | |
1937 | tsec->create_sid) { | |
1938 | *_new_isid = tsec->create_sid; | |
1939 | } else { | |
20cdef8d | 1940 | const struct inode_security_struct *dsec = inode_security(dir); |
aa8e712c SS |
1941 | return security_transition_sid(&selinux_state, tsec->sid, |
1942 | dsec->sid, tclass, | |
c3c188b2 DH |
1943 | name, _new_isid); |
1944 | } | |
1945 | ||
1946 | return 0; | |
1947 | } | |
1948 | ||
1da177e4 LT |
1949 | /* Check whether a task can create a file. */ |
1950 | static int may_create(struct inode *dir, | |
1951 | struct dentry *dentry, | |
1952 | u16 tclass) | |
1953 | { | |
5fb49870 | 1954 | const struct task_security_struct *tsec = current_security(); |
1da177e4 LT |
1955 | struct inode_security_struct *dsec; |
1956 | struct superblock_security_struct *sbsec; | |
275bb41e | 1957 | u32 sid, newsid; |
2bf49690 | 1958 | struct common_audit_data ad; |
1da177e4 LT |
1959 | int rc; |
1960 | ||
83da53c5 | 1961 | dsec = inode_security(dir); |
1da177e4 LT |
1962 | sbsec = dir->i_sb->s_security; |
1963 | ||
275bb41e | 1964 | sid = tsec->sid; |
275bb41e | 1965 | |
50c205f5 | 1966 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1967 | ad.u.dentry = dentry; |
1da177e4 | 1968 | |
6b6bc620 SS |
1969 | rc = avc_has_perm(&selinux_state, |
1970 | sid, dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
1971 | DIR__ADD_NAME | DIR__SEARCH, |
1972 | &ad); | |
1973 | if (rc) | |
1974 | return rc; | |
1975 | ||
c957f6df VG |
1976 | rc = selinux_determine_inode_label(current_security(), dir, |
1977 | &dentry->d_name, tclass, &newsid); | |
c3c188b2 DH |
1978 | if (rc) |
1979 | return rc; | |
1da177e4 | 1980 | |
6b6bc620 SS |
1981 | rc = avc_has_perm(&selinux_state, |
1982 | sid, newsid, tclass, FILE__CREATE, &ad); | |
1da177e4 LT |
1983 | if (rc) |
1984 | return rc; | |
1985 | ||
6b6bc620 SS |
1986 | return avc_has_perm(&selinux_state, |
1987 | newsid, sbsec->sid, | |
1da177e4 LT |
1988 | SECCLASS_FILESYSTEM, |
1989 | FILESYSTEM__ASSOCIATE, &ad); | |
1990 | } | |
1991 | ||
828dfe1d EP |
1992 | #define MAY_LINK 0 |
1993 | #define MAY_UNLINK 1 | |
1994 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1995 | |
1996 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1997 | static int may_link(struct inode *dir, | |
1998 | struct dentry *dentry, | |
1999 | int kind) | |
2000 | ||
2001 | { | |
1da177e4 | 2002 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 2003 | struct common_audit_data ad; |
275bb41e | 2004 | u32 sid = current_sid(); |
1da177e4 LT |
2005 | u32 av; |
2006 | int rc; | |
2007 | ||
83da53c5 AG |
2008 | dsec = inode_security(dir); |
2009 | isec = backing_inode_security(dentry); | |
1da177e4 | 2010 | |
50c205f5 | 2011 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2012 | ad.u.dentry = dentry; |
1da177e4 LT |
2013 | |
2014 | av = DIR__SEARCH; | |
2015 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
6b6bc620 SS |
2016 | rc = avc_has_perm(&selinux_state, |
2017 | sid, dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
2018 | if (rc) |
2019 | return rc; | |
2020 | ||
2021 | switch (kind) { | |
2022 | case MAY_LINK: | |
2023 | av = FILE__LINK; | |
2024 | break; | |
2025 | case MAY_UNLINK: | |
2026 | av = FILE__UNLINK; | |
2027 | break; | |
2028 | case MAY_RMDIR: | |
2029 | av = DIR__RMDIR; | |
2030 | break; | |
2031 | default: | |
744ba35e EP |
2032 | printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", |
2033 | __func__, kind); | |
1da177e4 LT |
2034 | return 0; |
2035 | } | |
2036 | ||
6b6bc620 SS |
2037 | rc = avc_has_perm(&selinux_state, |
2038 | sid, isec->sid, isec->sclass, av, &ad); | |
1da177e4 LT |
2039 | return rc; |
2040 | } | |
2041 | ||
2042 | static inline int may_rename(struct inode *old_dir, | |
2043 | struct dentry *old_dentry, | |
2044 | struct inode *new_dir, | |
2045 | struct dentry *new_dentry) | |
2046 | { | |
1da177e4 | 2047 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 2048 | struct common_audit_data ad; |
275bb41e | 2049 | u32 sid = current_sid(); |
1da177e4 LT |
2050 | u32 av; |
2051 | int old_is_dir, new_is_dir; | |
2052 | int rc; | |
2053 | ||
83da53c5 AG |
2054 | old_dsec = inode_security(old_dir); |
2055 | old_isec = backing_inode_security(old_dentry); | |
e36cb0b8 | 2056 | old_is_dir = d_is_dir(old_dentry); |
83da53c5 | 2057 | new_dsec = inode_security(new_dir); |
1da177e4 | 2058 | |
50c205f5 | 2059 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 2060 | |
a269434d | 2061 | ad.u.dentry = old_dentry; |
6b6bc620 SS |
2062 | rc = avc_has_perm(&selinux_state, |
2063 | sid, old_dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
2064 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
2065 | if (rc) | |
2066 | return rc; | |
6b6bc620 SS |
2067 | rc = avc_has_perm(&selinux_state, |
2068 | sid, old_isec->sid, | |
1da177e4 LT |
2069 | old_isec->sclass, FILE__RENAME, &ad); |
2070 | if (rc) | |
2071 | return rc; | |
2072 | if (old_is_dir && new_dir != old_dir) { | |
6b6bc620 SS |
2073 | rc = avc_has_perm(&selinux_state, |
2074 | sid, old_isec->sid, | |
1da177e4 LT |
2075 | old_isec->sclass, DIR__REPARENT, &ad); |
2076 | if (rc) | |
2077 | return rc; | |
2078 | } | |
2079 | ||
a269434d | 2080 | ad.u.dentry = new_dentry; |
1da177e4 | 2081 | av = DIR__ADD_NAME | DIR__SEARCH; |
2c616d4d | 2082 | if (d_is_positive(new_dentry)) |
1da177e4 | 2083 | av |= DIR__REMOVE_NAME; |
6b6bc620 SS |
2084 | rc = avc_has_perm(&selinux_state, |
2085 | sid, new_dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
2086 | if (rc) |
2087 | return rc; | |
2c616d4d | 2088 | if (d_is_positive(new_dentry)) { |
83da53c5 | 2089 | new_isec = backing_inode_security(new_dentry); |
e36cb0b8 | 2090 | new_is_dir = d_is_dir(new_dentry); |
6b6bc620 SS |
2091 | rc = avc_has_perm(&selinux_state, |
2092 | sid, new_isec->sid, | |
1da177e4 LT |
2093 | new_isec->sclass, |
2094 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
2095 | if (rc) | |
2096 | return rc; | |
2097 | } | |
2098 | ||
2099 | return 0; | |
2100 | } | |
2101 | ||
2102 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 2103 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
2104 | struct super_block *sb, |
2105 | u32 perms, | |
2bf49690 | 2106 | struct common_audit_data *ad) |
1da177e4 | 2107 | { |
1da177e4 | 2108 | struct superblock_security_struct *sbsec; |
88e67f3b | 2109 | u32 sid = cred_sid(cred); |
1da177e4 | 2110 | |
1da177e4 | 2111 | sbsec = sb->s_security; |
6b6bc620 SS |
2112 | return avc_has_perm(&selinux_state, |
2113 | sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); | |
1da177e4 LT |
2114 | } |
2115 | ||
2116 | /* Convert a Linux mode and permission mask to an access vector. */ | |
2117 | static inline u32 file_mask_to_av(int mode, int mask) | |
2118 | { | |
2119 | u32 av = 0; | |
2120 | ||
dba19c60 | 2121 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
2122 | if (mask & MAY_EXEC) |
2123 | av |= FILE__EXECUTE; | |
2124 | if (mask & MAY_READ) | |
2125 | av |= FILE__READ; | |
2126 | ||
2127 | if (mask & MAY_APPEND) | |
2128 | av |= FILE__APPEND; | |
2129 | else if (mask & MAY_WRITE) | |
2130 | av |= FILE__WRITE; | |
2131 | ||
2132 | } else { | |
2133 | if (mask & MAY_EXEC) | |
2134 | av |= DIR__SEARCH; | |
2135 | if (mask & MAY_WRITE) | |
2136 | av |= DIR__WRITE; | |
2137 | if (mask & MAY_READ) | |
2138 | av |= DIR__READ; | |
2139 | } | |
2140 | ||
2141 | return av; | |
2142 | } | |
2143 | ||
8b6a5a37 EP |
2144 | /* Convert a Linux file to an access vector. */ |
2145 | static inline u32 file_to_av(struct file *file) | |
2146 | { | |
2147 | u32 av = 0; | |
2148 | ||
2149 | if (file->f_mode & FMODE_READ) | |
2150 | av |= FILE__READ; | |
2151 | if (file->f_mode & FMODE_WRITE) { | |
2152 | if (file->f_flags & O_APPEND) | |
2153 | av |= FILE__APPEND; | |
2154 | else | |
2155 | av |= FILE__WRITE; | |
2156 | } | |
2157 | if (!av) { | |
2158 | /* | |
2159 | * Special file opened with flags 3 for ioctl-only use. | |
2160 | */ | |
2161 | av = FILE__IOCTL; | |
2162 | } | |
2163 | ||
2164 | return av; | |
2165 | } | |
2166 | ||
b0c636b9 | 2167 | /* |
8b6a5a37 | 2168 | * Convert a file to an access vector and include the correct open |
b0c636b9 EP |
2169 | * open permission. |
2170 | */ | |
8b6a5a37 | 2171 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 2172 | { |
8b6a5a37 | 2173 | u32 av = file_to_av(file); |
ccb54478 | 2174 | struct inode *inode = file_inode(file); |
b0c636b9 | 2175 | |
aa8e712c SS |
2176 | if (selinux_policycap_openperm() && |
2177 | inode->i_sb->s_magic != SOCKFS_MAGIC) | |
49b7b8de EP |
2178 | av |= FILE__OPEN; |
2179 | ||
b0c636b9 EP |
2180 | return av; |
2181 | } | |
2182 | ||
1da177e4 LT |
2183 | /* Hook functions begin here. */ |
2184 | ||
79af7307 SS |
2185 | static int selinux_binder_set_context_mgr(struct task_struct *mgr) |
2186 | { | |
2187 | u32 mysid = current_sid(); | |
2188 | u32 mgrsid = task_sid(mgr); | |
2189 | ||
6b6bc620 SS |
2190 | return avc_has_perm(&selinux_state, |
2191 | mysid, mgrsid, SECCLASS_BINDER, | |
79af7307 SS |
2192 | BINDER__SET_CONTEXT_MGR, NULL); |
2193 | } | |
2194 | ||
2195 | static int selinux_binder_transaction(struct task_struct *from, | |
2196 | struct task_struct *to) | |
2197 | { | |
2198 | u32 mysid = current_sid(); | |
2199 | u32 fromsid = task_sid(from); | |
2200 | u32 tosid = task_sid(to); | |
2201 | int rc; | |
2202 | ||
2203 | if (mysid != fromsid) { | |
6b6bc620 SS |
2204 | rc = avc_has_perm(&selinux_state, |
2205 | mysid, fromsid, SECCLASS_BINDER, | |
79af7307 SS |
2206 | BINDER__IMPERSONATE, NULL); |
2207 | if (rc) | |
2208 | return rc; | |
2209 | } | |
2210 | ||
6b6bc620 SS |
2211 | return avc_has_perm(&selinux_state, |
2212 | fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, | |
79af7307 SS |
2213 | NULL); |
2214 | } | |
2215 | ||
2216 | static int selinux_binder_transfer_binder(struct task_struct *from, | |
2217 | struct task_struct *to) | |
2218 | { | |
2219 | u32 fromsid = task_sid(from); | |
2220 | u32 tosid = task_sid(to); | |
2221 | ||
6b6bc620 SS |
2222 | return avc_has_perm(&selinux_state, |
2223 | fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, | |
79af7307 SS |
2224 | NULL); |
2225 | } | |
2226 | ||
2227 | static int selinux_binder_transfer_file(struct task_struct *from, | |
2228 | struct task_struct *to, | |
2229 | struct file *file) | |
2230 | { | |
2231 | u32 sid = task_sid(to); | |
2232 | struct file_security_struct *fsec = file->f_security; | |
83da53c5 | 2233 | struct dentry *dentry = file->f_path.dentry; |
20cdef8d | 2234 | struct inode_security_struct *isec; |
79af7307 SS |
2235 | struct common_audit_data ad; |
2236 | int rc; | |
2237 | ||
2238 | ad.type = LSM_AUDIT_DATA_PATH; | |
2239 | ad.u.path = file->f_path; | |
2240 | ||
2241 | if (sid != fsec->sid) { | |
6b6bc620 SS |
2242 | rc = avc_has_perm(&selinux_state, |
2243 | sid, fsec->sid, | |
79af7307 SS |
2244 | SECCLASS_FD, |
2245 | FD__USE, | |
2246 | &ad); | |
2247 | if (rc) | |
2248 | return rc; | |
2249 | } | |
2250 | ||
f66e448c CF |
2251 | #ifdef CONFIG_BPF_SYSCALL |
2252 | rc = bpf_fd_pass(file, sid); | |
2253 | if (rc) | |
2254 | return rc; | |
2255 | #endif | |
2256 | ||
83da53c5 | 2257 | if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
79af7307 SS |
2258 | return 0; |
2259 | ||
20cdef8d | 2260 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
2261 | return avc_has_perm(&selinux_state, |
2262 | sid, isec->sid, isec->sclass, file_to_av(file), | |
79af7307 SS |
2263 | &ad); |
2264 | } | |
2265 | ||
9e48858f | 2266 | static int selinux_ptrace_access_check(struct task_struct *child, |
5cd9c58f | 2267 | unsigned int mode) |
1da177e4 | 2268 | { |
be0554c9 SS |
2269 | u32 sid = current_sid(); |
2270 | u32 csid = task_sid(child); | |
2271 | ||
2272 | if (mode & PTRACE_MODE_READ) | |
6b6bc620 SS |
2273 | return avc_has_perm(&selinux_state, |
2274 | sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 | 2275 | |
6b6bc620 SS |
2276 | return avc_has_perm(&selinux_state, |
2277 | sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); | |
5cd9c58f DH |
2278 | } |
2279 | ||
2280 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
2281 | { | |
6b6bc620 SS |
2282 | return avc_has_perm(&selinux_state, |
2283 | task_sid(parent), current_sid(), SECCLASS_PROCESS, | |
be0554c9 | 2284 | PROCESS__PTRACE, NULL); |
1da177e4 LT |
2285 | } |
2286 | ||
2287 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 2288 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 | 2289 | { |
6b6bc620 SS |
2290 | return avc_has_perm(&selinux_state, |
2291 | current_sid(), task_sid(target), SECCLASS_PROCESS, | |
be0554c9 | 2292 | PROCESS__GETCAP, NULL); |
1da177e4 LT |
2293 | } |
2294 | ||
d84f4f99 DH |
2295 | static int selinux_capset(struct cred *new, const struct cred *old, |
2296 | const kernel_cap_t *effective, | |
2297 | const kernel_cap_t *inheritable, | |
2298 | const kernel_cap_t *permitted) | |
1da177e4 | 2299 | { |
6b6bc620 SS |
2300 | return avc_has_perm(&selinux_state, |
2301 | cred_sid(old), cred_sid(new), SECCLASS_PROCESS, | |
be0554c9 | 2302 | PROCESS__SETCAP, NULL); |
1da177e4 LT |
2303 | } |
2304 | ||
5626d3e8 JM |
2305 | /* |
2306 | * (This comment used to live with the selinux_task_setuid hook, | |
2307 | * which was removed). | |
2308 | * | |
2309 | * Since setuid only affects the current process, and since the SELinux | |
2310 | * controls are not based on the Linux identity attributes, SELinux does not | |
2311 | * need to control this operation. However, SELinux does control the use of | |
2312 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
2313 | */ | |
2314 | ||
6a9de491 EP |
2315 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
2316 | int cap, int audit) | |
1da177e4 | 2317 | { |
8e4ff6f2 | 2318 | return cred_has_capability(cred, cap, audit, ns == &init_user_ns); |
1da177e4 LT |
2319 | } |
2320 | ||
1da177e4 LT |
2321 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
2322 | { | |
88e67f3b | 2323 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2324 | int rc = 0; |
2325 | ||
2326 | if (!sb) | |
2327 | return 0; | |
2328 | ||
2329 | switch (cmds) { | |
828dfe1d EP |
2330 | case Q_SYNC: |
2331 | case Q_QUOTAON: | |
2332 | case Q_QUOTAOFF: | |
2333 | case Q_SETINFO: | |
2334 | case Q_SETQUOTA: | |
88e67f3b | 2335 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
2336 | break; |
2337 | case Q_GETFMT: | |
2338 | case Q_GETINFO: | |
2339 | case Q_GETQUOTA: | |
88e67f3b | 2340 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
2341 | break; |
2342 | default: | |
2343 | rc = 0; /* let the kernel handle invalid cmds */ | |
2344 | break; | |
1da177e4 LT |
2345 | } |
2346 | return rc; | |
2347 | } | |
2348 | ||
2349 | static int selinux_quota_on(struct dentry *dentry) | |
2350 | { | |
88e67f3b DH |
2351 | const struct cred *cred = current_cred(); |
2352 | ||
2875fa00 | 2353 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
2354 | } |
2355 | ||
12b3052c | 2356 | static int selinux_syslog(int type) |
1da177e4 | 2357 | { |
1da177e4 | 2358 | switch (type) { |
d78ca3cd KC |
2359 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2360 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
6b6bc620 SS |
2361 | return avc_has_perm(&selinux_state, |
2362 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2363 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); |
d78ca3cd KC |
2364 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2365 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2366 | /* Set level of messages printed to console */ | |
2367 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
6b6bc620 SS |
2368 | return avc_has_perm(&selinux_state, |
2369 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 SS |
2370 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, |
2371 | NULL); | |
1da177e4 | 2372 | } |
be0554c9 | 2373 | /* All other syslog types */ |
6b6bc620 SS |
2374 | return avc_has_perm(&selinux_state, |
2375 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2376 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); |
1da177e4 LT |
2377 | } |
2378 | ||
2379 | /* | |
2380 | * Check that a process has enough memory to allocate a new virtual | |
2381 | * mapping. 0 means there is enough memory for the allocation to | |
2382 | * succeed and -ENOMEM implies there is not. | |
2383 | * | |
1da177e4 LT |
2384 | * Do not audit the selinux permission check, as this is applied to all |
2385 | * processes that allocate mappings. | |
2386 | */ | |
34b4e4aa | 2387 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2388 | { |
2389 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2390 | |
b1d9e6b0 | 2391 | rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, |
8e4ff6f2 | 2392 | SECURITY_CAP_NOAUDIT, true); |
1da177e4 LT |
2393 | if (rc == 0) |
2394 | cap_sys_admin = 1; | |
2395 | ||
b1d9e6b0 | 2396 | return cap_sys_admin; |
1da177e4 LT |
2397 | } |
2398 | ||
2399 | /* binprm security operations */ | |
2400 | ||
be0554c9 | 2401 | static u32 ptrace_parent_sid(void) |
0c6181cb PM |
2402 | { |
2403 | u32 sid = 0; | |
2404 | struct task_struct *tracer; | |
2405 | ||
2406 | rcu_read_lock(); | |
be0554c9 | 2407 | tracer = ptrace_parent(current); |
0c6181cb PM |
2408 | if (tracer) |
2409 | sid = task_sid(tracer); | |
2410 | rcu_read_unlock(); | |
2411 | ||
2412 | return sid; | |
2413 | } | |
2414 | ||
7b0d0b40 SS |
2415 | static int check_nnp_nosuid(const struct linux_binprm *bprm, |
2416 | const struct task_security_struct *old_tsec, | |
2417 | const struct task_security_struct *new_tsec) | |
2418 | { | |
2419 | int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); | |
380cf5ba | 2420 | int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); |
7b0d0b40 | 2421 | int rc; |
af63f419 | 2422 | u32 av; |
7b0d0b40 SS |
2423 | |
2424 | if (!nnp && !nosuid) | |
2425 | return 0; /* neither NNP nor nosuid */ | |
2426 | ||
2427 | if (new_tsec->sid == old_tsec->sid) | |
2428 | return 0; /* No change in credentials */ | |
2429 | ||
2430 | /* | |
af63f419 SS |
2431 | * If the policy enables the nnp_nosuid_transition policy capability, |
2432 | * then we permit transitions under NNP or nosuid if the | |
2433 | * policy allows the corresponding permission between | |
2434 | * the old and new contexts. | |
7b0d0b40 | 2435 | */ |
aa8e712c | 2436 | if (selinux_policycap_nnp_nosuid_transition()) { |
af63f419 | 2437 | av = 0; |
7b0d0b40 | 2438 | if (nnp) |
af63f419 SS |
2439 | av |= PROCESS2__NNP_TRANSITION; |
2440 | if (nosuid) | |
2441 | av |= PROCESS2__NOSUID_TRANSITION; | |
6b6bc620 SS |
2442 | rc = avc_has_perm(&selinux_state, |
2443 | old_tsec->sid, new_tsec->sid, | |
af63f419 SS |
2444 | SECCLASS_PROCESS2, av, NULL); |
2445 | if (!rc) | |
2446 | return 0; | |
7b0d0b40 | 2447 | } |
af63f419 SS |
2448 | |
2449 | /* | |
2450 | * We also permit NNP or nosuid transitions to bounded SIDs, | |
2451 | * i.e. SIDs that are guaranteed to only be allowed a subset | |
2452 | * of the permissions of the current SID. | |
2453 | */ | |
aa8e712c SS |
2454 | rc = security_bounded_transition(&selinux_state, old_tsec->sid, |
2455 | new_tsec->sid); | |
af63f419 SS |
2456 | if (!rc) |
2457 | return 0; | |
2458 | ||
2459 | /* | |
2460 | * On failure, preserve the errno values for NNP vs nosuid. | |
2461 | * NNP: Operation not permitted for caller. | |
2462 | * nosuid: Permission denied to file. | |
2463 | */ | |
2464 | if (nnp) | |
2465 | return -EPERM; | |
2466 | return -EACCES; | |
7b0d0b40 SS |
2467 | } |
2468 | ||
a6f76f23 | 2469 | static int selinux_bprm_set_creds(struct linux_binprm *bprm) |
1da177e4 | 2470 | { |
a6f76f23 DH |
2471 | const struct task_security_struct *old_tsec; |
2472 | struct task_security_struct *new_tsec; | |
1da177e4 | 2473 | struct inode_security_struct *isec; |
2bf49690 | 2474 | struct common_audit_data ad; |
496ad9aa | 2475 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2476 | int rc; |
2477 | ||
a6f76f23 DH |
2478 | /* SELinux context only depends on initial program or script and not |
2479 | * the script interpreter */ | |
ddb4a144 | 2480 | if (bprm->called_set_creds) |
1da177e4 LT |
2481 | return 0; |
2482 | ||
a6f76f23 DH |
2483 | old_tsec = current_security(); |
2484 | new_tsec = bprm->cred->security; | |
83da53c5 | 2485 | isec = inode_security(inode); |
1da177e4 LT |
2486 | |
2487 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2488 | new_tsec->sid = old_tsec->sid; |
2489 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2490 | |
28eba5bf | 2491 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2492 | new_tsec->create_sid = 0; |
2493 | new_tsec->keycreate_sid = 0; | |
2494 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2495 | |
a6f76f23 DH |
2496 | if (old_tsec->exec_sid) { |
2497 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2498 | /* Reset exec SID on execve. */ |
a6f76f23 | 2499 | new_tsec->exec_sid = 0; |
259e5e6c | 2500 | |
7b0d0b40 SS |
2501 | /* Fail on NNP or nosuid if not an allowed transition. */ |
2502 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2503 | if (rc) | |
2504 | return rc; | |
1da177e4 LT |
2505 | } else { |
2506 | /* Check for a default transition on this program. */ | |
aa8e712c SS |
2507 | rc = security_transition_sid(&selinux_state, old_tsec->sid, |
2508 | isec->sid, SECCLASS_PROCESS, NULL, | |
652bb9b0 | 2509 | &new_tsec->sid); |
1da177e4 LT |
2510 | if (rc) |
2511 | return rc; | |
7b0d0b40 SS |
2512 | |
2513 | /* | |
2514 | * Fallback to old SID on NNP or nosuid if not an allowed | |
2515 | * transition. | |
2516 | */ | |
2517 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2518 | if (rc) | |
2519 | new_tsec->sid = old_tsec->sid; | |
1da177e4 LT |
2520 | } |
2521 | ||
43af5de7 VG |
2522 | ad.type = LSM_AUDIT_DATA_FILE; |
2523 | ad.u.file = bprm->file; | |
1da177e4 | 2524 | |
a6f76f23 | 2525 | if (new_tsec->sid == old_tsec->sid) { |
6b6bc620 SS |
2526 | rc = avc_has_perm(&selinux_state, |
2527 | old_tsec->sid, isec->sid, | |
1da177e4 LT |
2528 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2529 | if (rc) | |
2530 | return rc; | |
2531 | } else { | |
2532 | /* Check permissions for the transition. */ | |
6b6bc620 SS |
2533 | rc = avc_has_perm(&selinux_state, |
2534 | old_tsec->sid, new_tsec->sid, | |
1da177e4 LT |
2535 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2536 | if (rc) | |
2537 | return rc; | |
2538 | ||
6b6bc620 SS |
2539 | rc = avc_has_perm(&selinux_state, |
2540 | new_tsec->sid, isec->sid, | |
1da177e4 LT |
2541 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2542 | if (rc) | |
2543 | return rc; | |
2544 | ||
a6f76f23 DH |
2545 | /* Check for shared state */ |
2546 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
6b6bc620 SS |
2547 | rc = avc_has_perm(&selinux_state, |
2548 | old_tsec->sid, new_tsec->sid, | |
a6f76f23 DH |
2549 | SECCLASS_PROCESS, PROCESS__SHARE, |
2550 | NULL); | |
2551 | if (rc) | |
2552 | return -EPERM; | |
2553 | } | |
2554 | ||
2555 | /* Make sure that anyone attempting to ptrace over a task that | |
2556 | * changes its SID has the appropriate permit */ | |
9227dd2a | 2557 | if (bprm->unsafe & LSM_UNSAFE_PTRACE) { |
be0554c9 | 2558 | u32 ptsid = ptrace_parent_sid(); |
a6f76f23 | 2559 | if (ptsid != 0) { |
6b6bc620 SS |
2560 | rc = avc_has_perm(&selinux_state, |
2561 | ptsid, new_tsec->sid, | |
a6f76f23 DH |
2562 | SECCLASS_PROCESS, |
2563 | PROCESS__PTRACE, NULL); | |
2564 | if (rc) | |
2565 | return -EPERM; | |
2566 | } | |
2567 | } | |
1da177e4 | 2568 | |
a6f76f23 DH |
2569 | /* Clear any possibly unsafe personality bits on exec: */ |
2570 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
275bb41e | 2571 | |
1da177e4 LT |
2572 | /* Enable secure mode for SIDs transitions unless |
2573 | the noatsecure permission is granted between | |
2574 | the two SIDs, i.e. ahp returns 0. */ | |
6b6bc620 SS |
2575 | rc = avc_has_perm(&selinux_state, |
2576 | old_tsec->sid, new_tsec->sid, | |
62874c3a KC |
2577 | SECCLASS_PROCESS, PROCESS__NOATSECURE, |
2578 | NULL); | |
2579 | bprm->secureexec |= !!rc; | |
1da177e4 LT |
2580 | } |
2581 | ||
62874c3a | 2582 | return 0; |
1da177e4 LT |
2583 | } |
2584 | ||
c3c073f8 AV |
2585 | static int match_file(const void *p, struct file *file, unsigned fd) |
2586 | { | |
2587 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2588 | } | |
2589 | ||
1da177e4 | 2590 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2591 | static inline void flush_unauthorized_files(const struct cred *cred, |
2592 | struct files_struct *files) | |
1da177e4 | 2593 | { |
1da177e4 | 2594 | struct file *file, *devnull = NULL; |
b20c8122 | 2595 | struct tty_struct *tty; |
24ec839c | 2596 | int drop_tty = 0; |
c3c073f8 | 2597 | unsigned n; |
1da177e4 | 2598 | |
24ec839c | 2599 | tty = get_current_tty(); |
1da177e4 | 2600 | if (tty) { |
4a510969 | 2601 | spin_lock(&tty->files_lock); |
37dd0bd0 | 2602 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2603 | struct tty_file_private *file_priv; |
37dd0bd0 | 2604 | |
1da177e4 | 2605 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2606 | Use file_path_has_perm on the tty path directly |
2607 | rather than using file_has_perm, as this particular | |
2608 | open file may belong to another process and we are | |
2609 | only interested in the inode-based check here. */ | |
d996b62a NP |
2610 | file_priv = list_first_entry(&tty->tty_files, |
2611 | struct tty_file_private, list); | |
2612 | file = file_priv->file; | |
13f8e981 | 2613 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2614 | drop_tty = 1; |
1da177e4 | 2615 | } |
4a510969 | 2616 | spin_unlock(&tty->files_lock); |
452a00d2 | 2617 | tty_kref_put(tty); |
1da177e4 | 2618 | } |
98a27ba4 EB |
2619 | /* Reset controlling tty. */ |
2620 | if (drop_tty) | |
2621 | no_tty(); | |
1da177e4 LT |
2622 | |
2623 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2624 | n = iterate_fd(files, 0, match_file, cred); |
2625 | if (!n) /* none found? */ | |
2626 | return; | |
1da177e4 | 2627 | |
c3c073f8 | 2628 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2629 | if (IS_ERR(devnull)) |
2630 | devnull = NULL; | |
2631 | /* replace all the matching ones with this */ | |
2632 | do { | |
2633 | replace_fd(n - 1, devnull, 0); | |
2634 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2635 | if (devnull) | |
c3c073f8 | 2636 | fput(devnull); |
1da177e4 LT |
2637 | } |
2638 | ||
a6f76f23 DH |
2639 | /* |
2640 | * Prepare a process for imminent new credential changes due to exec | |
2641 | */ | |
2642 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2643 | { |
a6f76f23 DH |
2644 | struct task_security_struct *new_tsec; |
2645 | struct rlimit *rlim, *initrlim; | |
2646 | int rc, i; | |
d84f4f99 | 2647 | |
a6f76f23 DH |
2648 | new_tsec = bprm->cred->security; |
2649 | if (new_tsec->sid == new_tsec->osid) | |
2650 | return; | |
1da177e4 | 2651 | |
a6f76f23 DH |
2652 | /* Close files for which the new task SID is not authorized. */ |
2653 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2654 | |
a6f76f23 DH |
2655 | /* Always clear parent death signal on SID transitions. */ |
2656 | current->pdeath_signal = 0; | |
0356357c | 2657 | |
a6f76f23 DH |
2658 | /* Check whether the new SID can inherit resource limits from the old |
2659 | * SID. If not, reset all soft limits to the lower of the current | |
2660 | * task's hard limit and the init task's soft limit. | |
2661 | * | |
2662 | * Note that the setting of hard limits (even to lower them) can be | |
2663 | * controlled by the setrlimit check. The inclusion of the init task's | |
2664 | * soft limit into the computation is to avoid resetting soft limits | |
2665 | * higher than the default soft limit for cases where the default is | |
2666 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2667 | */ | |
6b6bc620 SS |
2668 | rc = avc_has_perm(&selinux_state, |
2669 | new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
a6f76f23 DH |
2670 | PROCESS__RLIMITINH, NULL); |
2671 | if (rc) { | |
eb2d55a3 ON |
2672 | /* protect against do_prlimit() */ |
2673 | task_lock(current); | |
a6f76f23 DH |
2674 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2675 | rlim = current->signal->rlim + i; | |
2676 | initrlim = init_task.signal->rlim + i; | |
2677 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2678 | } |
eb2d55a3 | 2679 | task_unlock(current); |
baa73d9e NP |
2680 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) |
2681 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2682 | } |
2683 | } | |
2684 | ||
2685 | /* | |
a6f76f23 DH |
2686 | * Clean up the process immediately after the installation of new credentials |
2687 | * due to exec | |
1da177e4 | 2688 | */ |
a6f76f23 | 2689 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2690 | { |
a6f76f23 | 2691 | const struct task_security_struct *tsec = current_security(); |
1da177e4 | 2692 | struct itimerval itimer; |
a6f76f23 | 2693 | u32 osid, sid; |
1da177e4 LT |
2694 | int rc, i; |
2695 | ||
a6f76f23 DH |
2696 | osid = tsec->osid; |
2697 | sid = tsec->sid; | |
2698 | ||
2699 | if (sid == osid) | |
1da177e4 LT |
2700 | return; |
2701 | ||
a6f76f23 DH |
2702 | /* Check whether the new SID can inherit signal state from the old SID. |
2703 | * If not, clear itimers to avoid subsequent signal generation and | |
2704 | * flush and unblock signals. | |
2705 | * | |
2706 | * This must occur _after_ the task SID has been updated so that any | |
2707 | * kill done after the flush will be checked against the new SID. | |
2708 | */ | |
6b6bc620 SS |
2709 | rc = avc_has_perm(&selinux_state, |
2710 | osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 | 2711 | if (rc) { |
baa73d9e NP |
2712 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) { |
2713 | memset(&itimer, 0, sizeof itimer); | |
2714 | for (i = 0; i < 3; i++) | |
2715 | do_setitimer(i, &itimer, NULL); | |
2716 | } | |
1da177e4 | 2717 | spin_lock_irq(¤t->sighand->siglock); |
9e7c8f8c ON |
2718 | if (!fatal_signal_pending(current)) { |
2719 | flush_sigqueue(¤t->pending); | |
2720 | flush_sigqueue(¤t->signal->shared_pending); | |
3bcac026 DH |
2721 | flush_signal_handlers(current, 1); |
2722 | sigemptyset(¤t->blocked); | |
9e7c8f8c | 2723 | recalc_sigpending(); |
3bcac026 | 2724 | } |
1da177e4 LT |
2725 | spin_unlock_irq(¤t->sighand->siglock); |
2726 | } | |
2727 | ||
a6f76f23 DH |
2728 | /* Wake up the parent if it is waiting so that it can recheck |
2729 | * wait permission to the new task SID. */ | |
ecd6de3c | 2730 | read_lock(&tasklist_lock); |
0b7570e7 | 2731 | __wake_up_parent(current, current->real_parent); |
ecd6de3c | 2732 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2733 | } |
2734 | ||
2735 | /* superblock security operations */ | |
2736 | ||
2737 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2738 | { | |
2739 | return superblock_alloc_security(sb); | |
2740 | } | |
2741 | ||
2742 | static void selinux_sb_free_security(struct super_block *sb) | |
2743 | { | |
2744 | superblock_free_security(sb); | |
2745 | } | |
2746 | ||
2747 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2748 | { | |
2749 | if (plen > olen) | |
2750 | return 0; | |
2751 | ||
2752 | return !memcmp(prefix, option, plen); | |
2753 | } | |
2754 | ||
2755 | static inline int selinux_option(char *option, int len) | |
2756 | { | |
832cbd9a EP |
2757 | return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || |
2758 | match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || | |
2759 | match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || | |
11689d47 DQ |
2760 | match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || |
2761 | match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); | |
1da177e4 LT |
2762 | } |
2763 | ||
2764 | static inline void take_option(char **to, char *from, int *first, int len) | |
2765 | { | |
2766 | if (!*first) { | |
2767 | **to = ','; | |
2768 | *to += 1; | |
3528a953 | 2769 | } else |
1da177e4 LT |
2770 | *first = 0; |
2771 | memcpy(*to, from, len); | |
2772 | *to += len; | |
2773 | } | |
2774 | ||
828dfe1d EP |
2775 | static inline void take_selinux_option(char **to, char *from, int *first, |
2776 | int len) | |
3528a953 CO |
2777 | { |
2778 | int current_size = 0; | |
2779 | ||
2780 | if (!*first) { | |
2781 | **to = '|'; | |
2782 | *to += 1; | |
828dfe1d | 2783 | } else |
3528a953 CO |
2784 | *first = 0; |
2785 | ||
2786 | while (current_size < len) { | |
2787 | if (*from != '"') { | |
2788 | **to = *from; | |
2789 | *to += 1; | |
2790 | } | |
2791 | from += 1; | |
2792 | current_size += 1; | |
2793 | } | |
2794 | } | |
2795 | ||
e0007529 | 2796 | static int selinux_sb_copy_data(char *orig, char *copy) |
1da177e4 LT |
2797 | { |
2798 | int fnosec, fsec, rc = 0; | |
2799 | char *in_save, *in_curr, *in_end; | |
2800 | char *sec_curr, *nosec_save, *nosec; | |
3528a953 | 2801 | int open_quote = 0; |
1da177e4 LT |
2802 | |
2803 | in_curr = orig; | |
2804 | sec_curr = copy; | |
2805 | ||
1da177e4 LT |
2806 | nosec = (char *)get_zeroed_page(GFP_KERNEL); |
2807 | if (!nosec) { | |
2808 | rc = -ENOMEM; | |
2809 | goto out; | |
2810 | } | |
2811 | ||
2812 | nosec_save = nosec; | |
2813 | fnosec = fsec = 1; | |
2814 | in_save = in_end = orig; | |
2815 | ||
2816 | do { | |
3528a953 CO |
2817 | if (*in_end == '"') |
2818 | open_quote = !open_quote; | |
2819 | if ((*in_end == ',' && open_quote == 0) || | |
2820 | *in_end == '\0') { | |
1da177e4 LT |
2821 | int len = in_end - in_curr; |
2822 | ||
2823 | if (selinux_option(in_curr, len)) | |
3528a953 | 2824 | take_selinux_option(&sec_curr, in_curr, &fsec, len); |
1da177e4 LT |
2825 | else |
2826 | take_option(&nosec, in_curr, &fnosec, len); | |
2827 | ||
2828 | in_curr = in_end + 1; | |
2829 | } | |
2830 | } while (*in_end++); | |
2831 | ||
6931dfc9 | 2832 | strcpy(in_save, nosec_save); |
da3caa20 | 2833 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
2834 | out: |
2835 | return rc; | |
2836 | } | |
2837 | ||
026eb167 EP |
2838 | static int selinux_sb_remount(struct super_block *sb, void *data) |
2839 | { | |
2840 | int rc, i, *flags; | |
2841 | struct security_mnt_opts opts; | |
2842 | char *secdata, **mount_options; | |
2843 | struct superblock_security_struct *sbsec = sb->s_security; | |
2844 | ||
2845 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2846 | return 0; | |
2847 | ||
2848 | if (!data) | |
2849 | return 0; | |
2850 | ||
2851 | if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) | |
2852 | return 0; | |
2853 | ||
2854 | security_init_mnt_opts(&opts); | |
2855 | secdata = alloc_secdata(); | |
2856 | if (!secdata) | |
2857 | return -ENOMEM; | |
2858 | rc = selinux_sb_copy_data(data, secdata); | |
2859 | if (rc) | |
2860 | goto out_free_secdata; | |
2861 | ||
2862 | rc = selinux_parse_opts_str(secdata, &opts); | |
2863 | if (rc) | |
2864 | goto out_free_secdata; | |
2865 | ||
2866 | mount_options = opts.mnt_opts; | |
2867 | flags = opts.mnt_opts_flags; | |
2868 | ||
2869 | for (i = 0; i < opts.num_mnt_opts; i++) { | |
2870 | u32 sid; | |
026eb167 | 2871 | |
12f348b9 | 2872 | if (flags[i] == SBLABEL_MNT) |
026eb167 | 2873 | continue; |
aa8e712c SS |
2874 | rc = security_context_str_to_sid(&selinux_state, |
2875 | mount_options[i], &sid, | |
2876 | GFP_KERNEL); | |
026eb167 | 2877 | if (rc) { |
44be2f65 | 2878 | printk(KERN_WARNING "SELinux: security_context_str_to_sid" |
29b1deb2 LT |
2879 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
2880 | mount_options[i], sb->s_id, sb->s_type->name, rc); | |
026eb167 EP |
2881 | goto out_free_opts; |
2882 | } | |
2883 | rc = -EINVAL; | |
2884 | switch (flags[i]) { | |
2885 | case FSCONTEXT_MNT: | |
2886 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) | |
2887 | goto out_bad_option; | |
2888 | break; | |
2889 | case CONTEXT_MNT: | |
2890 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2891 | goto out_bad_option; | |
2892 | break; | |
2893 | case ROOTCONTEXT_MNT: { | |
2894 | struct inode_security_struct *root_isec; | |
83da53c5 | 2895 | root_isec = backing_inode_security(sb->s_root); |
026eb167 EP |
2896 | |
2897 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2898 | goto out_bad_option; | |
2899 | break; | |
2900 | } | |
2901 | case DEFCONTEXT_MNT: | |
2902 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2903 | goto out_bad_option; | |
2904 | break; | |
2905 | default: | |
2906 | goto out_free_opts; | |
2907 | } | |
2908 | } | |
2909 | ||
2910 | rc = 0; | |
2911 | out_free_opts: | |
2912 | security_free_mnt_opts(&opts); | |
2913 | out_free_secdata: | |
2914 | free_secdata(secdata); | |
2915 | return rc; | |
2916 | out_bad_option: | |
2917 | printk(KERN_WARNING "SELinux: unable to change security options " | |
29b1deb2 LT |
2918 | "during remount (dev %s, type=%s)\n", sb->s_id, |
2919 | sb->s_type->name); | |
026eb167 EP |
2920 | goto out_free_opts; |
2921 | } | |
2922 | ||
12204e24 | 2923 | static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) |
1da177e4 | 2924 | { |
88e67f3b | 2925 | const struct cred *cred = current_cred(); |
2bf49690 | 2926 | struct common_audit_data ad; |
1da177e4 LT |
2927 | int rc; |
2928 | ||
2929 | rc = superblock_doinit(sb, data); | |
2930 | if (rc) | |
2931 | return rc; | |
2932 | ||
74192246 JM |
2933 | /* Allow all mounts performed by the kernel */ |
2934 | if (flags & MS_KERNMOUNT) | |
2935 | return 0; | |
2936 | ||
50c205f5 | 2937 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2938 | ad.u.dentry = sb->s_root; |
88e67f3b | 2939 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2940 | } |
2941 | ||
726c3342 | 2942 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2943 | { |
88e67f3b | 2944 | const struct cred *cred = current_cred(); |
2bf49690 | 2945 | struct common_audit_data ad; |
1da177e4 | 2946 | |
50c205f5 | 2947 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2948 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2949 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2950 | } |
2951 | ||
808d4e3c | 2952 | static int selinux_mount(const char *dev_name, |
8a04c43b | 2953 | const struct path *path, |
808d4e3c | 2954 | const char *type, |
828dfe1d EP |
2955 | unsigned long flags, |
2956 | void *data) | |
1da177e4 | 2957 | { |
88e67f3b | 2958 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2959 | |
2960 | if (flags & MS_REMOUNT) | |
d8c9584e | 2961 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2962 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2963 | else |
2875fa00 | 2964 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2965 | } |
2966 | ||
2967 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2968 | { | |
88e67f3b | 2969 | const struct cred *cred = current_cred(); |
1da177e4 | 2970 | |
88e67f3b | 2971 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2972 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2973 | } |
2974 | ||
2975 | /* inode security operations */ | |
2976 | ||
2977 | static int selinux_inode_alloc_security(struct inode *inode) | |
2978 | { | |
2979 | return inode_alloc_security(inode); | |
2980 | } | |
2981 | ||
2982 | static void selinux_inode_free_security(struct inode *inode) | |
2983 | { | |
2984 | inode_free_security(inode); | |
2985 | } | |
2986 | ||
d47be3df | 2987 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
4f3ccd76 | 2988 | const struct qstr *name, void **ctx, |
d47be3df DQ |
2989 | u32 *ctxlen) |
2990 | { | |
d47be3df DQ |
2991 | u32 newsid; |
2992 | int rc; | |
2993 | ||
c957f6df VG |
2994 | rc = selinux_determine_inode_label(current_security(), |
2995 | d_inode(dentry->d_parent), name, | |
c3c188b2 DH |
2996 | inode_mode_to_security_class(mode), |
2997 | &newsid); | |
2998 | if (rc) | |
2999 | return rc; | |
d47be3df | 3000 | |
aa8e712c SS |
3001 | return security_sid_to_context(&selinux_state, newsid, (char **)ctx, |
3002 | ctxlen); | |
d47be3df DQ |
3003 | } |
3004 | ||
a518b0a5 VG |
3005 | static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, |
3006 | struct qstr *name, | |
3007 | const struct cred *old, | |
3008 | struct cred *new) | |
3009 | { | |
3010 | u32 newsid; | |
3011 | int rc; | |
3012 | struct task_security_struct *tsec; | |
3013 | ||
3014 | rc = selinux_determine_inode_label(old->security, | |
3015 | d_inode(dentry->d_parent), name, | |
3016 | inode_mode_to_security_class(mode), | |
3017 | &newsid); | |
3018 | if (rc) | |
3019 | return rc; | |
3020 | ||
3021 | tsec = new->security; | |
3022 | tsec->create_sid = newsid; | |
3023 | return 0; | |
3024 | } | |
3025 | ||
5e41ff9e | 3026 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
3027 | const struct qstr *qstr, |
3028 | const char **name, | |
2a7dba39 | 3029 | void **value, size_t *len) |
5e41ff9e | 3030 | { |
5fb49870 | 3031 | const struct task_security_struct *tsec = current_security(); |
5e41ff9e | 3032 | struct superblock_security_struct *sbsec; |
c0d4f464 | 3033 | u32 newsid, clen; |
5e41ff9e | 3034 | int rc; |
9548906b | 3035 | char *context; |
5e41ff9e | 3036 | |
5e41ff9e | 3037 | sbsec = dir->i_sb->s_security; |
5e41ff9e | 3038 | |
275bb41e DH |
3039 | newsid = tsec->create_sid; |
3040 | ||
c957f6df | 3041 | rc = selinux_determine_inode_label(current_security(), |
c3c188b2 DH |
3042 | dir, qstr, |
3043 | inode_mode_to_security_class(inode->i_mode), | |
3044 | &newsid); | |
3045 | if (rc) | |
3046 | return rc; | |
5e41ff9e | 3047 | |
296fddf7 | 3048 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 3049 | if (sbsec->flags & SE_SBINITIALIZED) { |
296fddf7 EP |
3050 | struct inode_security_struct *isec = inode->i_security; |
3051 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
3052 | isec->sid = newsid; | |
6f3be9f5 | 3053 | isec->initialized = LABEL_INITIALIZED; |
296fddf7 | 3054 | } |
5e41ff9e | 3055 | |
aa8e712c | 3056 | if (!selinux_state.initialized || !(sbsec->flags & SBLABEL_MNT)) |
25a74f3b SS |
3057 | return -EOPNOTSUPP; |
3058 | ||
9548906b TH |
3059 | if (name) |
3060 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 3061 | |
570bc1c2 | 3062 | if (value && len) { |
aa8e712c SS |
3063 | rc = security_sid_to_context_force(&selinux_state, newsid, |
3064 | &context, &clen); | |
9548906b | 3065 | if (rc) |
570bc1c2 | 3066 | return rc; |
570bc1c2 SS |
3067 | *value = context; |
3068 | *len = clen; | |
5e41ff9e | 3069 | } |
5e41ff9e | 3070 | |
5e41ff9e SS |
3071 | return 0; |
3072 | } | |
3073 | ||
4acdaf27 | 3074 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
3075 | { |
3076 | return may_create(dir, dentry, SECCLASS_FILE); | |
3077 | } | |
3078 | ||
1da177e4 LT |
3079 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
3080 | { | |
1da177e4 LT |
3081 | return may_link(dir, old_dentry, MAY_LINK); |
3082 | } | |
3083 | ||
1da177e4 LT |
3084 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
3085 | { | |
1da177e4 LT |
3086 | return may_link(dir, dentry, MAY_UNLINK); |
3087 | } | |
3088 | ||
3089 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
3090 | { | |
3091 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
3092 | } | |
3093 | ||
18bb1db3 | 3094 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
3095 | { |
3096 | return may_create(dir, dentry, SECCLASS_DIR); | |
3097 | } | |
3098 | ||
1da177e4 LT |
3099 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
3100 | { | |
3101 | return may_link(dir, dentry, MAY_RMDIR); | |
3102 | } | |
3103 | ||
1a67aafb | 3104 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 3105 | { |
1da177e4 LT |
3106 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
3107 | } | |
3108 | ||
1da177e4 | 3109 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 3110 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
3111 | { |
3112 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
3113 | } | |
3114 | ||
1da177e4 LT |
3115 | static int selinux_inode_readlink(struct dentry *dentry) |
3116 | { | |
88e67f3b DH |
3117 | const struct cred *cred = current_cred(); |
3118 | ||
2875fa00 | 3119 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
3120 | } |
3121 | ||
bda0be7a N |
3122 | static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, |
3123 | bool rcu) | |
1da177e4 | 3124 | { |
88e67f3b | 3125 | const struct cred *cred = current_cred(); |
bda0be7a N |
3126 | struct common_audit_data ad; |
3127 | struct inode_security_struct *isec; | |
3128 | u32 sid; | |
1da177e4 | 3129 | |
bda0be7a N |
3130 | validate_creds(cred); |
3131 | ||
3132 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
3133 | ad.u.dentry = dentry; | |
3134 | sid = cred_sid(cred); | |
5d226df4 AG |
3135 | isec = inode_security_rcu(inode, rcu); |
3136 | if (IS_ERR(isec)) | |
3137 | return PTR_ERR(isec); | |
bda0be7a | 3138 | |
6b6bc620 SS |
3139 | return avc_has_perm_flags(&selinux_state, |
3140 | sid, isec->sid, isec->sclass, FILE__READ, &ad, | |
bda0be7a | 3141 | rcu ? MAY_NOT_BLOCK : 0); |
1da177e4 LT |
3142 | } |
3143 | ||
d4cf970d EP |
3144 | static noinline int audit_inode_permission(struct inode *inode, |
3145 | u32 perms, u32 audited, u32 denied, | |
626b9740 | 3146 | int result, |
d4cf970d | 3147 | unsigned flags) |
1da177e4 | 3148 | { |
b782e0a6 | 3149 | struct common_audit_data ad; |
d4cf970d EP |
3150 | struct inode_security_struct *isec = inode->i_security; |
3151 | int rc; | |
3152 | ||
50c205f5 | 3153 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
3154 | ad.u.inode = inode; |
3155 | ||
6b6bc620 SS |
3156 | rc = slow_avc_audit(&selinux_state, |
3157 | current_sid(), isec->sid, isec->sclass, perms, | |
626b9740 | 3158 | audited, denied, result, &ad, flags); |
d4cf970d EP |
3159 | if (rc) |
3160 | return rc; | |
3161 | return 0; | |
3162 | } | |
3163 | ||
e74f71eb | 3164 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 3165 | { |
88e67f3b | 3166 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
3167 | u32 perms; |
3168 | bool from_access; | |
cf1dd1da | 3169 | unsigned flags = mask & MAY_NOT_BLOCK; |
2e334057 EP |
3170 | struct inode_security_struct *isec; |
3171 | u32 sid; | |
3172 | struct av_decision avd; | |
3173 | int rc, rc2; | |
3174 | u32 audited, denied; | |
1da177e4 | 3175 | |
b782e0a6 | 3176 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
3177 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
3178 | ||
b782e0a6 EP |
3179 | /* No permission to check. Existence test. */ |
3180 | if (!mask) | |
1da177e4 | 3181 | return 0; |
1da177e4 | 3182 | |
2e334057 | 3183 | validate_creds(cred); |
b782e0a6 | 3184 | |
2e334057 EP |
3185 | if (unlikely(IS_PRIVATE(inode))) |
3186 | return 0; | |
b782e0a6 EP |
3187 | |
3188 | perms = file_mask_to_av(inode->i_mode, mask); | |
3189 | ||
2e334057 | 3190 | sid = cred_sid(cred); |
5d226df4 AG |
3191 | isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK); |
3192 | if (IS_ERR(isec)) | |
3193 | return PTR_ERR(isec); | |
2e334057 | 3194 | |
6b6bc620 SS |
3195 | rc = avc_has_perm_noaudit(&selinux_state, |
3196 | sid, isec->sid, isec->sclass, perms, 0, &avd); | |
2e334057 EP |
3197 | audited = avc_audit_required(perms, &avd, rc, |
3198 | from_access ? FILE__AUDIT_ACCESS : 0, | |
3199 | &denied); | |
3200 | if (likely(!audited)) | |
3201 | return rc; | |
3202 | ||
626b9740 | 3203 | rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags); |
2e334057 EP |
3204 | if (rc2) |
3205 | return rc2; | |
3206 | return rc; | |
1da177e4 LT |
3207 | } |
3208 | ||
3209 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
3210 | { | |
88e67f3b | 3211 | const struct cred *cred = current_cred(); |
ccb54478 | 3212 | struct inode *inode = d_backing_inode(dentry); |
bc6a6008 | 3213 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 3214 | __u32 av = FILE__WRITE; |
1da177e4 | 3215 | |
bc6a6008 AW |
3216 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
3217 | if (ia_valid & ATTR_FORCE) { | |
3218 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
3219 | ATTR_FORCE); | |
3220 | if (!ia_valid) | |
3221 | return 0; | |
3222 | } | |
1da177e4 | 3223 | |
bc6a6008 AW |
3224 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
3225 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 3226 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 3227 | |
aa8e712c | 3228 | if (selinux_policycap_openperm() && |
ccb54478 SS |
3229 | inode->i_sb->s_magic != SOCKFS_MAGIC && |
3230 | (ia_valid & ATTR_SIZE) && | |
3231 | !(ia_valid & ATTR_FILE)) | |
95dbf739 EP |
3232 | av |= FILE__OPEN; |
3233 | ||
3234 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
3235 | } |
3236 | ||
3f7036a0 | 3237 | static int selinux_inode_getattr(const struct path *path) |
1da177e4 | 3238 | { |
3f7036a0 | 3239 | return path_has_perm(current_cred(), path, FILE__GETATTR); |
1da177e4 LT |
3240 | } |
3241 | ||
db59000a SS |
3242 | static bool has_cap_mac_admin(bool audit) |
3243 | { | |
3244 | const struct cred *cred = current_cred(); | |
3245 | int cap_audit = audit ? SECURITY_CAP_AUDIT : SECURITY_CAP_NOAUDIT; | |
3246 | ||
3247 | if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, cap_audit)) | |
3248 | return false; | |
3249 | if (cred_has_capability(cred, CAP_MAC_ADMIN, cap_audit, true)) | |
3250 | return false; | |
3251 | return true; | |
3252 | } | |
3253 | ||
8f0cfa52 DH |
3254 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
3255 | const void *value, size_t size, int flags) | |
1da177e4 | 3256 | { |
c6f493d6 | 3257 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3258 | struct inode_security_struct *isec; |
1da177e4 | 3259 | struct superblock_security_struct *sbsec; |
2bf49690 | 3260 | struct common_audit_data ad; |
275bb41e | 3261 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
3262 | int rc = 0; |
3263 | ||
6b240306 EB |
3264 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3265 | rc = cap_inode_setxattr(dentry, name, value, size, flags); | |
3266 | if (rc) | |
3267 | return rc; | |
3268 | ||
3269 | /* Not an attribute we recognize, so just check the | |
3270 | ordinary setattr permission. */ | |
3271 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3272 | } | |
1da177e4 LT |
3273 | |
3274 | sbsec = inode->i_sb->s_security; | |
12f348b9 | 3275 | if (!(sbsec->flags & SBLABEL_MNT)) |
1da177e4 LT |
3276 | return -EOPNOTSUPP; |
3277 | ||
2e149670 | 3278 | if (!inode_owner_or_capable(inode)) |
1da177e4 LT |
3279 | return -EPERM; |
3280 | ||
50c205f5 | 3281 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 3282 | ad.u.dentry = dentry; |
1da177e4 | 3283 | |
20cdef8d | 3284 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
3285 | rc = avc_has_perm(&selinux_state, |
3286 | sid, isec->sid, isec->sclass, | |
1da177e4 LT |
3287 | FILE__RELABELFROM, &ad); |
3288 | if (rc) | |
3289 | return rc; | |
3290 | ||
aa8e712c SS |
3291 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3292 | GFP_KERNEL); | |
12b29f34 | 3293 | if (rc == -EINVAL) { |
db59000a | 3294 | if (!has_cap_mac_admin(true)) { |
d6ea83ec EP |
3295 | struct audit_buffer *ab; |
3296 | size_t audit_size; | |
d6ea83ec EP |
3297 | |
3298 | /* We strip a nul only if it is at the end, otherwise the | |
3299 | * context contains a nul and we should audit that */ | |
e3fea3f7 | 3300 | if (value) { |
add24372 CIK |
3301 | const char *str = value; |
3302 | ||
e3fea3f7 AV |
3303 | if (str[size - 1] == '\0') |
3304 | audit_size = size - 1; | |
3305 | else | |
3306 | audit_size = size; | |
3307 | } else { | |
e3fea3f7 AV |
3308 | audit_size = 0; |
3309 | } | |
cdfb6b34 RGB |
3310 | ab = audit_log_start(audit_context(), |
3311 | GFP_ATOMIC, AUDIT_SELINUX_ERR); | |
d6ea83ec EP |
3312 | audit_log_format(ab, "op=setxattr invalid_context="); |
3313 | audit_log_n_untrustedstring(ab, value, audit_size); | |
3314 | audit_log_end(ab); | |
3315 | ||
12b29f34 | 3316 | return rc; |
d6ea83ec | 3317 | } |
aa8e712c SS |
3318 | rc = security_context_to_sid_force(&selinux_state, value, |
3319 | size, &newsid); | |
12b29f34 | 3320 | } |
1da177e4 LT |
3321 | if (rc) |
3322 | return rc; | |
3323 | ||
6b6bc620 SS |
3324 | rc = avc_has_perm(&selinux_state, |
3325 | sid, newsid, isec->sclass, | |
1da177e4 LT |
3326 | FILE__RELABELTO, &ad); |
3327 | if (rc) | |
3328 | return rc; | |
3329 | ||
aa8e712c SS |
3330 | rc = security_validate_transition(&selinux_state, isec->sid, newsid, |
3331 | sid, isec->sclass); | |
1da177e4 LT |
3332 | if (rc) |
3333 | return rc; | |
3334 | ||
6b6bc620 SS |
3335 | return avc_has_perm(&selinux_state, |
3336 | newsid, | |
1da177e4 LT |
3337 | sbsec->sid, |
3338 | SECCLASS_FILESYSTEM, | |
3339 | FILESYSTEM__ASSOCIATE, | |
3340 | &ad); | |
3341 | } | |
3342 | ||
8f0cfa52 | 3343 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 3344 | const void *value, size_t size, |
8f0cfa52 | 3345 | int flags) |
1da177e4 | 3346 | { |
c6f493d6 | 3347 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3348 | struct inode_security_struct *isec; |
1da177e4 LT |
3349 | u32 newsid; |
3350 | int rc; | |
3351 | ||
3352 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
3353 | /* Not an attribute we recognize, so nothing to do. */ | |
3354 | return; | |
3355 | } | |
3356 | ||
aa8e712c SS |
3357 | rc = security_context_to_sid_force(&selinux_state, value, size, |
3358 | &newsid); | |
1da177e4 | 3359 | if (rc) { |
12b29f34 SS |
3360 | printk(KERN_ERR "SELinux: unable to map context to SID" |
3361 | "for (%s, %lu), rc=%d\n", | |
3362 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
3363 | return; |
3364 | } | |
3365 | ||
20cdef8d | 3366 | isec = backing_inode_security(dentry); |
9287aed2 | 3367 | spin_lock(&isec->lock); |
aa9c2669 | 3368 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3369 | isec->sid = newsid; |
6f3be9f5 | 3370 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3371 | spin_unlock(&isec->lock); |
aa9c2669 | 3372 | |
1da177e4 LT |
3373 | return; |
3374 | } | |
3375 | ||
8f0cfa52 | 3376 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 3377 | { |
88e67f3b DH |
3378 | const struct cred *cred = current_cred(); |
3379 | ||
2875fa00 | 3380 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3381 | } |
3382 | ||
828dfe1d | 3383 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 3384 | { |
88e67f3b DH |
3385 | const struct cred *cred = current_cred(); |
3386 | ||
2875fa00 | 3387 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3388 | } |
3389 | ||
8f0cfa52 | 3390 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 3391 | { |
6b240306 EB |
3392 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3393 | int rc = cap_inode_removexattr(dentry, name); | |
3394 | if (rc) | |
3395 | return rc; | |
3396 | ||
3397 | /* Not an attribute we recognize, so just check the | |
3398 | ordinary setattr permission. */ | |
3399 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3400 | } | |
1da177e4 LT |
3401 | |
3402 | /* No one is allowed to remove a SELinux security label. | |
3403 | You can change the label, but all data must be labeled. */ | |
3404 | return -EACCES; | |
3405 | } | |
3406 | ||
d381d8a9 | 3407 | /* |
abc69bb6 | 3408 | * Copy the inode security context value to the user. |
d381d8a9 JM |
3409 | * |
3410 | * Permission check is handled by selinux_inode_getxattr hook. | |
3411 | */ | |
ea861dfd | 3412 | static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 3413 | { |
42492594 DQ |
3414 | u32 size; |
3415 | int error; | |
3416 | char *context = NULL; | |
20cdef8d | 3417 | struct inode_security_struct *isec; |
d381d8a9 | 3418 | |
8c8570fb DK |
3419 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
3420 | return -EOPNOTSUPP; | |
d381d8a9 | 3421 | |
abc69bb6 SS |
3422 | /* |
3423 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3424 | * value even if it is not defined by current policy; otherwise, | |
3425 | * use the in-core value under current policy. | |
3426 | * Use the non-auditing forms of the permission checks since | |
3427 | * getxattr may be called by unprivileged processes commonly | |
3428 | * and lack of permission just means that we fall back to the | |
3429 | * in-core context value, not a denial. | |
3430 | */ | |
20cdef8d | 3431 | isec = inode_security(inode); |
db59000a | 3432 | if (has_cap_mac_admin(false)) |
aa8e712c SS |
3433 | error = security_sid_to_context_force(&selinux_state, |
3434 | isec->sid, &context, | |
abc69bb6 SS |
3435 | &size); |
3436 | else | |
aa8e712c SS |
3437 | error = security_sid_to_context(&selinux_state, isec->sid, |
3438 | &context, &size); | |
42492594 DQ |
3439 | if (error) |
3440 | return error; | |
3441 | error = size; | |
3442 | if (alloc) { | |
3443 | *buffer = context; | |
3444 | goto out_nofree; | |
3445 | } | |
3446 | kfree(context); | |
3447 | out_nofree: | |
3448 | return error; | |
1da177e4 LT |
3449 | } |
3450 | ||
3451 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 3452 | const void *value, size_t size, int flags) |
1da177e4 | 3453 | { |
2c97165b | 3454 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
1da177e4 LT |
3455 | u32 newsid; |
3456 | int rc; | |
3457 | ||
3458 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3459 | return -EOPNOTSUPP; | |
3460 | ||
3461 | if (!value || !size) | |
3462 | return -EACCES; | |
3463 | ||
aa8e712c SS |
3464 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3465 | GFP_KERNEL); | |
1da177e4 LT |
3466 | if (rc) |
3467 | return rc; | |
3468 | ||
9287aed2 | 3469 | spin_lock(&isec->lock); |
aa9c2669 | 3470 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3471 | isec->sid = newsid; |
6f3be9f5 | 3472 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3473 | spin_unlock(&isec->lock); |
1da177e4 LT |
3474 | return 0; |
3475 | } | |
3476 | ||
3477 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3478 | { | |
3479 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3480 | if (buffer && len <= buffer_size) | |
3481 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3482 | return len; | |
3483 | } | |
3484 | ||
d6335d77 | 3485 | static void selinux_inode_getsecid(struct inode *inode, u32 *secid) |
713a04ae | 3486 | { |
e817c2f3 | 3487 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
713a04ae AD |
3488 | *secid = isec->sid; |
3489 | } | |
3490 | ||
56909eb3 VG |
3491 | static int selinux_inode_copy_up(struct dentry *src, struct cred **new) |
3492 | { | |
3493 | u32 sid; | |
3494 | struct task_security_struct *tsec; | |
3495 | struct cred *new_creds = *new; | |
3496 | ||
3497 | if (new_creds == NULL) { | |
3498 | new_creds = prepare_creds(); | |
3499 | if (!new_creds) | |
3500 | return -ENOMEM; | |
3501 | } | |
3502 | ||
3503 | tsec = new_creds->security; | |
3504 | /* Get label from overlay inode and set it in create_sid */ | |
3505 | selinux_inode_getsecid(d_inode(src), &sid); | |
3506 | tsec->create_sid = sid; | |
3507 | *new = new_creds; | |
3508 | return 0; | |
3509 | } | |
3510 | ||
19472b69 VG |
3511 | static int selinux_inode_copy_up_xattr(const char *name) |
3512 | { | |
3513 | /* The copy_up hook above sets the initial context on an inode, but we | |
3514 | * don't then want to overwrite it by blindly copying all the lower | |
3515 | * xattrs up. Instead, we have to filter out SELinux-related xattrs. | |
3516 | */ | |
3517 | if (strcmp(name, XATTR_NAME_SELINUX) == 0) | |
3518 | return 1; /* Discard */ | |
3519 | /* | |
3520 | * Any other attribute apart from SELINUX is not claimed, supported | |
3521 | * by selinux. | |
3522 | */ | |
3523 | return -EOPNOTSUPP; | |
3524 | } | |
3525 | ||
1da177e4 LT |
3526 | /* file security operations */ |
3527 | ||
788e7dd4 | 3528 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3529 | { |
88e67f3b | 3530 | const struct cred *cred = current_cred(); |
496ad9aa | 3531 | struct inode *inode = file_inode(file); |
1da177e4 | 3532 | |
1da177e4 LT |
3533 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3534 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3535 | mask |= MAY_APPEND; | |
3536 | ||
389fb800 PM |
3537 | return file_has_perm(cred, file, |
3538 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3539 | } |
3540 | ||
788e7dd4 YN |
3541 | static int selinux_file_permission(struct file *file, int mask) |
3542 | { | |
496ad9aa | 3543 | struct inode *inode = file_inode(file); |
20dda18b | 3544 | struct file_security_struct *fsec = file->f_security; |
b197367e | 3545 | struct inode_security_struct *isec; |
20dda18b SS |
3546 | u32 sid = current_sid(); |
3547 | ||
389fb800 | 3548 | if (!mask) |
788e7dd4 YN |
3549 | /* No permission to check. Existence test. */ |
3550 | return 0; | |
788e7dd4 | 3551 | |
b197367e | 3552 | isec = inode_security(inode); |
20dda18b | 3553 | if (sid == fsec->sid && fsec->isid == isec->sid && |
6b6bc620 | 3554 | fsec->pseqno == avc_policy_seqno(&selinux_state)) |
83d49856 | 3555 | /* No change since file_open check. */ |
20dda18b SS |
3556 | return 0; |
3557 | ||
788e7dd4 YN |
3558 | return selinux_revalidate_file_permission(file, mask); |
3559 | } | |
3560 | ||
1da177e4 LT |
3561 | static int selinux_file_alloc_security(struct file *file) |
3562 | { | |
3563 | return file_alloc_security(file); | |
3564 | } | |
3565 | ||
3566 | static void selinux_file_free_security(struct file *file) | |
3567 | { | |
3568 | file_free_security(file); | |
3569 | } | |
3570 | ||
fa1aa143 JVS |
3571 | /* |
3572 | * Check whether a task has the ioctl permission and cmd | |
3573 | * operation to an inode. | |
3574 | */ | |
1d2a168a | 3575 | static int ioctl_has_perm(const struct cred *cred, struct file *file, |
fa1aa143 JVS |
3576 | u32 requested, u16 cmd) |
3577 | { | |
3578 | struct common_audit_data ad; | |
3579 | struct file_security_struct *fsec = file->f_security; | |
3580 | struct inode *inode = file_inode(file); | |
20cdef8d | 3581 | struct inode_security_struct *isec; |
fa1aa143 JVS |
3582 | struct lsm_ioctlop_audit ioctl; |
3583 | u32 ssid = cred_sid(cred); | |
3584 | int rc; | |
3585 | u8 driver = cmd >> 8; | |
3586 | u8 xperm = cmd & 0xff; | |
3587 | ||
3588 | ad.type = LSM_AUDIT_DATA_IOCTL_OP; | |
3589 | ad.u.op = &ioctl; | |
3590 | ad.u.op->cmd = cmd; | |
3591 | ad.u.op->path = file->f_path; | |
3592 | ||
3593 | if (ssid != fsec->sid) { | |
6b6bc620 SS |
3594 | rc = avc_has_perm(&selinux_state, |
3595 | ssid, fsec->sid, | |
fa1aa143 JVS |
3596 | SECCLASS_FD, |
3597 | FD__USE, | |
3598 | &ad); | |
3599 | if (rc) | |
3600 | goto out; | |
3601 | } | |
3602 | ||
3603 | if (unlikely(IS_PRIVATE(inode))) | |
3604 | return 0; | |
3605 | ||
20cdef8d | 3606 | isec = inode_security(inode); |
6b6bc620 SS |
3607 | rc = avc_has_extended_perms(&selinux_state, |
3608 | ssid, isec->sid, isec->sclass, | |
3609 | requested, driver, xperm, &ad); | |
fa1aa143 JVS |
3610 | out: |
3611 | return rc; | |
3612 | } | |
3613 | ||
1da177e4 LT |
3614 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
3615 | unsigned long arg) | |
3616 | { | |
88e67f3b | 3617 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3618 | int error = 0; |
1da177e4 | 3619 | |
0b24dcb7 EP |
3620 | switch (cmd) { |
3621 | case FIONREAD: | |
3622 | /* fall through */ | |
3623 | case FIBMAP: | |
3624 | /* fall through */ | |
3625 | case FIGETBSZ: | |
3626 | /* fall through */ | |
2f99c369 | 3627 | case FS_IOC_GETFLAGS: |
0b24dcb7 | 3628 | /* fall through */ |
2f99c369 | 3629 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3630 | error = file_has_perm(cred, file, FILE__GETATTR); |
3631 | break; | |
1da177e4 | 3632 | |
2f99c369 | 3633 | case FS_IOC_SETFLAGS: |
0b24dcb7 | 3634 | /* fall through */ |
2f99c369 | 3635 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3636 | error = file_has_perm(cred, file, FILE__SETATTR); |
3637 | break; | |
3638 | ||
3639 | /* sys_ioctl() checks */ | |
3640 | case FIONBIO: | |
3641 | /* fall through */ | |
3642 | case FIOASYNC: | |
3643 | error = file_has_perm(cred, file, 0); | |
3644 | break; | |
1da177e4 | 3645 | |
0b24dcb7 EP |
3646 | case KDSKBENT: |
3647 | case KDSKBSENT: | |
6a9de491 | 3648 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
8e4ff6f2 | 3649 | SECURITY_CAP_AUDIT, true); |
0b24dcb7 EP |
3650 | break; |
3651 | ||
3652 | /* default case assumes that the command will go | |
3653 | * to the file's ioctl() function. | |
3654 | */ | |
3655 | default: | |
fa1aa143 | 3656 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
0b24dcb7 EP |
3657 | } |
3658 | return error; | |
1da177e4 LT |
3659 | } |
3660 | ||
fcaaade1 SS |
3661 | static int default_noexec; |
3662 | ||
1da177e4 LT |
3663 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3664 | { | |
88e67f3b | 3665 | const struct cred *cred = current_cred(); |
be0554c9 | 3666 | u32 sid = cred_sid(cred); |
d84f4f99 | 3667 | int rc = 0; |
88e67f3b | 3668 | |
fcaaade1 | 3669 | if (default_noexec && |
892e8cac SS |
3670 | (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || |
3671 | (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3672 | /* |
3673 | * We are making executable an anonymous mapping or a | |
3674 | * private file mapping that will also be writable. | |
3675 | * This has an additional check. | |
3676 | */ | |
6b6bc620 SS |
3677 | rc = avc_has_perm(&selinux_state, |
3678 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3679 | PROCESS__EXECMEM, NULL); |
1da177e4 | 3680 | if (rc) |
d84f4f99 | 3681 | goto error; |
1da177e4 | 3682 | } |
1da177e4 LT |
3683 | |
3684 | if (file) { | |
3685 | /* read access is always possible with a mapping */ | |
3686 | u32 av = FILE__READ; | |
3687 | ||
3688 | /* write access only matters if the mapping is shared */ | |
3689 | if (shared && (prot & PROT_WRITE)) | |
3690 | av |= FILE__WRITE; | |
3691 | ||
3692 | if (prot & PROT_EXEC) | |
3693 | av |= FILE__EXECUTE; | |
3694 | ||
88e67f3b | 3695 | return file_has_perm(cred, file, av); |
1da177e4 | 3696 | } |
d84f4f99 DH |
3697 | |
3698 | error: | |
3699 | return rc; | |
1da177e4 LT |
3700 | } |
3701 | ||
e5467859 | 3702 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3703 | { |
b1d9e6b0 | 3704 | int rc = 0; |
1da177e4 | 3705 | |
a2551df7 | 3706 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
98883bfd | 3707 | u32 sid = current_sid(); |
6b6bc620 SS |
3708 | rc = avc_has_perm(&selinux_state, |
3709 | sid, sid, SECCLASS_MEMPROTECT, | |
ed032189 | 3710 | MEMPROTECT__MMAP_ZERO, NULL); |
84336d1a EP |
3711 | } |
3712 | ||
98883bfd | 3713 | return rc; |
e5467859 | 3714 | } |
1da177e4 | 3715 | |
e5467859 AV |
3716 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3717 | unsigned long prot, unsigned long flags) | |
3718 | { | |
3ba4bf5f SS |
3719 | struct common_audit_data ad; |
3720 | int rc; | |
3721 | ||
3722 | if (file) { | |
3723 | ad.type = LSM_AUDIT_DATA_FILE; | |
3724 | ad.u.file = file; | |
3725 | rc = inode_has_perm(current_cred(), file_inode(file), | |
3726 | FILE__MAP, &ad); | |
3727 | if (rc) | |
3728 | return rc; | |
3729 | } | |
3730 | ||
aa8e712c | 3731 | if (selinux_state.checkreqprot) |
1da177e4 LT |
3732 | prot = reqprot; |
3733 | ||
3734 | return file_map_prot_check(file, prot, | |
3735 | (flags & MAP_TYPE) == MAP_SHARED); | |
3736 | } | |
3737 | ||
3738 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3739 | unsigned long reqprot, | |
3740 | unsigned long prot) | |
3741 | { | |
88e67f3b | 3742 | const struct cred *cred = current_cred(); |
be0554c9 | 3743 | u32 sid = cred_sid(cred); |
1da177e4 | 3744 | |
aa8e712c | 3745 | if (selinux_state.checkreqprot) |
1da177e4 LT |
3746 | prot = reqprot; |
3747 | ||
fcaaade1 SS |
3748 | if (default_noexec && |
3749 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3750 | int rc = 0; |
db4c9641 SS |
3751 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3752 | vma->vm_end <= vma->vm_mm->brk) { | |
6b6bc620 SS |
3753 | rc = avc_has_perm(&selinux_state, |
3754 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3755 | PROCESS__EXECHEAP, NULL); |
db4c9641 | 3756 | } else if (!vma->vm_file && |
c2316dbf SS |
3757 | ((vma->vm_start <= vma->vm_mm->start_stack && |
3758 | vma->vm_end >= vma->vm_mm->start_stack) || | |
d17af505 | 3759 | vma_is_stack_for_current(vma))) { |
6b6bc620 SS |
3760 | rc = avc_has_perm(&selinux_state, |
3761 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3762 | PROCESS__EXECSTACK, NULL); |
db4c9641 SS |
3763 | } else if (vma->vm_file && vma->anon_vma) { |
3764 | /* | |
3765 | * We are making executable a file mapping that has | |
3766 | * had some COW done. Since pages might have been | |
3767 | * written, check ability to execute the possibly | |
3768 | * modified content. This typically should only | |
3769 | * occur for text relocations. | |
3770 | */ | |
d84f4f99 | 3771 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3772 | } |