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> |
e262e32d | 91 | #include <uapi/linux/mount.h> |
1da177e4 LT |
92 | |
93 | #include "avc.h" | |
94 | #include "objsec.h" | |
95 | #include "netif.h" | |
224dfbd8 | 96 | #include "netnode.h" |
3e112172 | 97 | #include "netport.h" |
409dcf31 | 98 | #include "ibpkey.h" |
d28d1e08 | 99 | #include "xfrm.h" |
c60475bf | 100 | #include "netlabel.h" |
9d57a7f9 | 101 | #include "audit.h" |
7b98a585 | 102 | #include "avc_ss.h" |
1da177e4 | 103 | |
aa8e712c SS |
104 | struct selinux_state selinux_state; |
105 | ||
d621d35e | 106 | /* SECMARK reference count */ |
56a4ca99 | 107 | static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); |
d621d35e | 108 | |
1da177e4 | 109 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
aa8e712c | 110 | static int selinux_enforcing_boot; |
1da177e4 LT |
111 | |
112 | static int __init enforcing_setup(char *str) | |
113 | { | |
f5269710 | 114 | unsigned long enforcing; |
29707b20 | 115 | if (!kstrtoul(str, 0, &enforcing)) |
aa8e712c | 116 | selinux_enforcing_boot = enforcing ? 1 : 0; |
1da177e4 LT |
117 | return 1; |
118 | } | |
119 | __setup("enforcing=", enforcing_setup); | |
aa8e712c SS |
120 | #else |
121 | #define selinux_enforcing_boot 1 | |
1da177e4 LT |
122 | #endif |
123 | ||
124 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM | |
125 | int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; | |
126 | ||
127 | static int __init selinux_enabled_setup(char *str) | |
128 | { | |
f5269710 | 129 | unsigned long enabled; |
29707b20 | 130 | if (!kstrtoul(str, 0, &enabled)) |
f5269710 | 131 | selinux_enabled = enabled ? 1 : 0; |
1da177e4 LT |
132 | return 1; |
133 | } | |
134 | __setup("selinux=", selinux_enabled_setup); | |
30d55280 SS |
135 | #else |
136 | int selinux_enabled = 1; | |
1da177e4 LT |
137 | #endif |
138 | ||
aa8e712c SS |
139 | static unsigned int selinux_checkreqprot_boot = |
140 | CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE; | |
141 | ||
142 | static int __init checkreqprot_setup(char *str) | |
143 | { | |
144 | unsigned long checkreqprot; | |
145 | ||
146 | if (!kstrtoul(str, 0, &checkreqprot)) | |
147 | selinux_checkreqprot_boot = checkreqprot ? 1 : 0; | |
148 | return 1; | |
149 | } | |
150 | __setup("checkreqprot=", checkreqprot_setup); | |
151 | ||
e18b890b | 152 | static struct kmem_cache *sel_inode_cache; |
63205654 | 153 | static struct kmem_cache *file_security_cache; |
7cae7e26 | 154 | |
d621d35e PM |
155 | /** |
156 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
157 | * | |
158 | * Description: | |
159 | * This function checks the SECMARK reference counter to see if any SECMARK | |
160 | * targets are currently configured, if the reference counter is greater than | |
161 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
2be4d74f CP |
162 | * enabled, false (0) if SECMARK is disabled. If the always_check_network |
163 | * policy capability is enabled, SECMARK is always considered enabled. | |
d621d35e PM |
164 | * |
165 | */ | |
166 | static int selinux_secmark_enabled(void) | |
167 | { | |
aa8e712c SS |
168 | return (selinux_policycap_alwaysnetwork() || |
169 | atomic_read(&selinux_secmark_refcount)); | |
2be4d74f CP |
170 | } |
171 | ||
172 | /** | |
173 | * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled | |
174 | * | |
175 | * Description: | |
176 | * This function checks if NetLabel or labeled IPSEC is enabled. Returns true | |
177 | * (1) if any are enabled or false (0) if neither are enabled. If the | |
178 | * always_check_network policy capability is enabled, peer labeling | |
179 | * is always considered enabled. | |
180 | * | |
181 | */ | |
182 | static int selinux_peerlbl_enabled(void) | |
183 | { | |
aa8e712c SS |
184 | return (selinux_policycap_alwaysnetwork() || |
185 | netlbl_enabled() || selinux_xfrm_enabled()); | |
d621d35e PM |
186 | } |
187 | ||
615e51fd PM |
188 | static int selinux_netcache_avc_callback(u32 event) |
189 | { | |
190 | if (event == AVC_CALLBACK_RESET) { | |
191 | sel_netif_flush(); | |
192 | sel_netnode_flush(); | |
193 | sel_netport_flush(); | |
194 | synchronize_net(); | |
195 | } | |
196 | return 0; | |
197 | } | |
198 | ||
8f408ab6 DJ |
199 | static int selinux_lsm_notifier_avc_callback(u32 event) |
200 | { | |
409dcf31 DJ |
201 | if (event == AVC_CALLBACK_RESET) { |
202 | sel_ib_pkey_flush(); | |
8f408ab6 | 203 | call_lsm_notifier(LSM_POLICY_CHANGE, NULL); |
409dcf31 | 204 | } |
8f408ab6 DJ |
205 | |
206 | return 0; | |
207 | } | |
208 | ||
d84f4f99 DH |
209 | /* |
210 | * initialise the security for the init task | |
211 | */ | |
212 | static void cred_init_security(void) | |
1da177e4 | 213 | { |
3b11a1de | 214 | struct cred *cred = (struct cred *) current->real_cred; |
1da177e4 LT |
215 | struct task_security_struct *tsec; |
216 | ||
89d155ef | 217 | tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); |
1da177e4 | 218 | if (!tsec) |
d84f4f99 | 219 | panic("SELinux: Failed to initialize initial task.\n"); |
1da177e4 | 220 | |
d84f4f99 | 221 | tsec->osid = tsec->sid = SECINITSID_KERNEL; |
f1752eec | 222 | cred->security = tsec; |
1da177e4 LT |
223 | } |
224 | ||
88e67f3b DH |
225 | /* |
226 | * get the security ID of a set of credentials | |
227 | */ | |
228 | static inline u32 cred_sid(const struct cred *cred) | |
229 | { | |
230 | const struct task_security_struct *tsec; | |
231 | ||
232 | tsec = cred->security; | |
233 | return tsec->sid; | |
234 | } | |
235 | ||
275bb41e | 236 | /* |
3b11a1de | 237 | * get the objective security ID of a task |
275bb41e DH |
238 | */ |
239 | static inline u32 task_sid(const struct task_struct *task) | |
240 | { | |
275bb41e DH |
241 | u32 sid; |
242 | ||
243 | rcu_read_lock(); | |
88e67f3b | 244 | sid = cred_sid(__task_cred(task)); |
275bb41e DH |
245 | rcu_read_unlock(); |
246 | return sid; | |
247 | } | |
248 | ||
88e67f3b DH |
249 | /* Allocate and free functions for each kind of security blob. */ |
250 | ||
1da177e4 LT |
251 | static int inode_alloc_security(struct inode *inode) |
252 | { | |
1da177e4 | 253 | struct inode_security_struct *isec; |
275bb41e | 254 | u32 sid = current_sid(); |
1da177e4 | 255 | |
a02fe132 | 256 | isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); |
1da177e4 LT |
257 | if (!isec) |
258 | return -ENOMEM; | |
259 | ||
9287aed2 | 260 | spin_lock_init(&isec->lock); |
1da177e4 | 261 | INIT_LIST_HEAD(&isec->list); |
1da177e4 LT |
262 | isec->inode = inode; |
263 | isec->sid = SECINITSID_UNLABELED; | |
264 | isec->sclass = SECCLASS_FILE; | |
275bb41e | 265 | isec->task_sid = sid; |
42059112 | 266 | isec->initialized = LABEL_INVALID; |
1da177e4 LT |
267 | inode->i_security = isec; |
268 | ||
269 | return 0; | |
270 | } | |
271 | ||
5d226df4 AG |
272 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); |
273 | ||
274 | /* | |
275 | * Try reloading inode security labels that have been marked as invalid. The | |
276 | * @may_sleep parameter indicates when sleeping and thus reloading labels is | |
42059112 | 277 | * allowed; when set to false, returns -ECHILD when the label is |
e9193288 | 278 | * invalid. The @dentry parameter should be set to a dentry of the inode. |
5d226df4 AG |
279 | */ |
280 | static int __inode_security_revalidate(struct inode *inode, | |
e9193288 | 281 | struct dentry *dentry, |
5d226df4 AG |
282 | bool may_sleep) |
283 | { | |
284 | struct inode_security_struct *isec = inode->i_security; | |
285 | ||
286 | might_sleep_if(may_sleep); | |
287 | ||
aa8e712c SS |
288 | if (selinux_state.initialized && |
289 | isec->initialized != LABEL_INITIALIZED) { | |
5d226df4 AG |
290 | if (!may_sleep) |
291 | return -ECHILD; | |
292 | ||
293 | /* | |
294 | * Try reloading the inode security label. This will fail if | |
295 | * @opt_dentry is NULL and no dentry for this inode can be | |
296 | * found; in that case, continue using the old label. | |
297 | */ | |
e9193288 | 298 | inode_doinit_with_dentry(inode, dentry); |
5d226df4 AG |
299 | } |
300 | return 0; | |
301 | } | |
302 | ||
5d226df4 AG |
303 | static struct inode_security_struct *inode_security_novalidate(struct inode *inode) |
304 | { | |
305 | return inode->i_security; | |
306 | } | |
307 | ||
308 | static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) | |
309 | { | |
310 | int error; | |
311 | ||
312 | error = __inode_security_revalidate(inode, NULL, !rcu); | |
313 | if (error) | |
314 | return ERR_PTR(error); | |
315 | return inode->i_security; | |
316 | } | |
317 | ||
83da53c5 AG |
318 | /* |
319 | * Get the security label of an inode. | |
320 | */ | |
321 | static struct inode_security_struct *inode_security(struct inode *inode) | |
322 | { | |
5d226df4 | 323 | __inode_security_revalidate(inode, NULL, true); |
83da53c5 AG |
324 | return inode->i_security; |
325 | } | |
326 | ||
2c97165b PM |
327 | static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) |
328 | { | |
329 | struct inode *inode = d_backing_inode(dentry); | |
330 | ||
331 | return inode->i_security; | |
332 | } | |
333 | ||
83da53c5 AG |
334 | /* |
335 | * Get the security label of a dentry's backing inode. | |
336 | */ | |
337 | static struct inode_security_struct *backing_inode_security(struct dentry *dentry) | |
338 | { | |
339 | struct inode *inode = d_backing_inode(dentry); | |
340 | ||
5d226df4 | 341 | __inode_security_revalidate(inode, dentry, true); |
83da53c5 AG |
342 | return inode->i_security; |
343 | } | |
344 | ||
3dc91d43 SR |
345 | static void inode_free_rcu(struct rcu_head *head) |
346 | { | |
347 | struct inode_security_struct *isec; | |
348 | ||
349 | isec = container_of(head, struct inode_security_struct, rcu); | |
350 | kmem_cache_free(sel_inode_cache, isec); | |
351 | } | |
352 | ||
1da177e4 LT |
353 | static void inode_free_security(struct inode *inode) |
354 | { | |
355 | struct inode_security_struct *isec = inode->i_security; | |
356 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
357 | ||
9629d04a WL |
358 | /* |
359 | * As not all inode security structures are in a list, we check for | |
360 | * empty list outside of the lock to make sure that we won't waste | |
361 | * time taking a lock doing nothing. | |
362 | * | |
363 | * The list_del_init() function can be safely called more than once. | |
364 | * It should not be possible for this function to be called with | |
365 | * concurrent list_add(), but for better safety against future changes | |
366 | * in the code, we use list_empty_careful() here. | |
367 | */ | |
368 | if (!list_empty_careful(&isec->list)) { | |
369 | spin_lock(&sbsec->isec_lock); | |
1da177e4 | 370 | list_del_init(&isec->list); |
9629d04a WL |
371 | spin_unlock(&sbsec->isec_lock); |
372 | } | |
1da177e4 | 373 | |
3dc91d43 SR |
374 | /* |
375 | * The inode may still be referenced in a path walk and | |
376 | * a call to selinux_inode_permission() can be made | |
377 | * after inode_free_security() is called. Ideally, the VFS | |
378 | * wouldn't do this, but fixing that is a much harder | |
379 | * job. For now, simply free the i_security via RCU, and | |
380 | * leave the current inode->i_security pointer intact. | |
381 | * The inode will be freed after the RCU grace period too. | |
382 | */ | |
383 | call_rcu(&isec->rcu, inode_free_rcu); | |
1da177e4 LT |
384 | } |
385 | ||
386 | static int file_alloc_security(struct file *file) | |
387 | { | |
1da177e4 | 388 | struct file_security_struct *fsec; |
275bb41e | 389 | u32 sid = current_sid(); |
1da177e4 | 390 | |
63205654 | 391 | fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL); |
1da177e4 LT |
392 | if (!fsec) |
393 | return -ENOMEM; | |
394 | ||
275bb41e DH |
395 | fsec->sid = sid; |
396 | fsec->fown_sid = sid; | |
1da177e4 LT |
397 | file->f_security = fsec; |
398 | ||
399 | return 0; | |
400 | } | |
401 | ||
402 | static void file_free_security(struct file *file) | |
403 | { | |
404 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 | 405 | file->f_security = NULL; |
63205654 | 406 | kmem_cache_free(file_security_cache, fsec); |
1da177e4 LT |
407 | } |
408 | ||
409 | static int superblock_alloc_security(struct super_block *sb) | |
410 | { | |
411 | struct superblock_security_struct *sbsec; | |
412 | ||
89d155ef | 413 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
414 | if (!sbsec) |
415 | return -ENOMEM; | |
416 | ||
bc7e982b | 417 | mutex_init(&sbsec->lock); |
1da177e4 LT |
418 | INIT_LIST_HEAD(&sbsec->isec_head); |
419 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
420 | sbsec->sb = sb; |
421 | sbsec->sid = SECINITSID_UNLABELED; | |
422 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 423 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
424 | sb->s_security = sbsec; |
425 | ||
426 | return 0; | |
427 | } | |
428 | ||
429 | static void superblock_free_security(struct super_block *sb) | |
430 | { | |
431 | struct superblock_security_struct *sbsec = sb->s_security; | |
1da177e4 LT |
432 | sb->s_security = NULL; |
433 | kfree(sbsec); | |
434 | } | |
435 | ||
1da177e4 LT |
436 | static inline int inode_doinit(struct inode *inode) |
437 | { | |
438 | return inode_doinit_with_dentry(inode, NULL); | |
439 | } | |
440 | ||
441 | enum { | |
31e87930 | 442 | Opt_error = -1, |
1da177e4 LT |
443 | Opt_context = 1, |
444 | Opt_fscontext = 2, | |
c9180a57 EP |
445 | Opt_defcontext = 3, |
446 | Opt_rootcontext = 4, | |
11689d47 | 447 | Opt_labelsupport = 5, |
d355987f | 448 | Opt_nextmntopt = 6, |
1da177e4 LT |
449 | }; |
450 | ||
d355987f EP |
451 | #define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) |
452 | ||
a447c093 | 453 | static const match_table_t tokens = { |
832cbd9a EP |
454 | {Opt_context, CONTEXT_STR "%s"}, |
455 | {Opt_fscontext, FSCONTEXT_STR "%s"}, | |
456 | {Opt_defcontext, DEFCONTEXT_STR "%s"}, | |
457 | {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, | |
11689d47 | 458 | {Opt_labelsupport, LABELSUPP_STR}, |
31e87930 | 459 | {Opt_error, NULL}, |
1da177e4 LT |
460 | }; |
461 | ||
462 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
463 | ||
c312feb2 EP |
464 | static int may_context_mount_sb_relabel(u32 sid, |
465 | struct superblock_security_struct *sbsec, | |
275bb41e | 466 | const struct cred *cred) |
c312feb2 | 467 | { |
275bb41e | 468 | const struct task_security_struct *tsec = cred->security; |
c312feb2 EP |
469 | int rc; |
470 | ||
6b6bc620 SS |
471 | rc = avc_has_perm(&selinux_state, |
472 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
473 | FILESYSTEM__RELABELFROM, NULL); |
474 | if (rc) | |
475 | return rc; | |
476 | ||
6b6bc620 SS |
477 | rc = avc_has_perm(&selinux_state, |
478 | tsec->sid, sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
479 | FILESYSTEM__RELABELTO, NULL); |
480 | return rc; | |
481 | } | |
482 | ||
0808925e EP |
483 | static int may_context_mount_inode_relabel(u32 sid, |
484 | struct superblock_security_struct *sbsec, | |
275bb41e | 485 | const struct cred *cred) |
0808925e | 486 | { |
275bb41e | 487 | const struct task_security_struct *tsec = cred->security; |
0808925e | 488 | int rc; |
6b6bc620 SS |
489 | rc = avc_has_perm(&selinux_state, |
490 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
491 | FILESYSTEM__RELABELFROM, NULL); |
492 | if (rc) | |
493 | return rc; | |
494 | ||
6b6bc620 SS |
495 | rc = avc_has_perm(&selinux_state, |
496 | sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
497 | FILESYSTEM__ASSOCIATE, NULL); |
498 | return rc; | |
499 | } | |
500 | ||
b43e725d EP |
501 | static int selinux_is_sblabel_mnt(struct super_block *sb) |
502 | { | |
503 | struct superblock_security_struct *sbsec = sb->s_security; | |
504 | ||
d5f3a5f6 MS |
505 | return sbsec->behavior == SECURITY_FS_USE_XATTR || |
506 | sbsec->behavior == SECURITY_FS_USE_TRANS || | |
507 | sbsec->behavior == SECURITY_FS_USE_TASK || | |
9fc2b4b4 | 508 | sbsec->behavior == SECURITY_FS_USE_NATIVE || |
d5f3a5f6 MS |
509 | /* Special handling. Genfs but also in-core setxattr handler */ |
510 | !strcmp(sb->s_type->name, "sysfs") || | |
511 | !strcmp(sb->s_type->name, "pstore") || | |
512 | !strcmp(sb->s_type->name, "debugfs") || | |
a2c7c6fb | 513 | !strcmp(sb->s_type->name, "tracefs") || |
2651225b | 514 | !strcmp(sb->s_type->name, "rootfs") || |
aa8e712c | 515 | (selinux_policycap_cgroupseclabel() && |
2651225b SS |
516 | (!strcmp(sb->s_type->name, "cgroup") || |
517 | !strcmp(sb->s_type->name, "cgroup2"))); | |
b43e725d EP |
518 | } |
519 | ||
c9180a57 | 520 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 521 | { |
1da177e4 | 522 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 | 523 | struct dentry *root = sb->s_root; |
c6f493d6 | 524 | struct inode *root_inode = d_backing_inode(root); |
c9180a57 | 525 | int rc = 0; |
1da177e4 | 526 | |
c9180a57 EP |
527 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
528 | /* Make sure that the xattr handler exists and that no | |
529 | error other than -ENODATA is returned by getxattr on | |
530 | the root directory. -ENODATA is ok, as this may be | |
531 | the first boot of the SELinux kernel before we have | |
532 | assigned xattr values to the filesystem. */ | |
5d6c3191 | 533 | if (!(root_inode->i_opflags & IOP_XATTR)) { |
c103a91e | 534 | pr_warn("SELinux: (dev %s, type %s) has no " |
29b1deb2 | 535 | "xattr support\n", sb->s_id, sb->s_type->name); |
c9180a57 EP |
536 | rc = -EOPNOTSUPP; |
537 | goto out; | |
538 | } | |
5d6c3191 AG |
539 | |
540 | rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); | |
c9180a57 EP |
541 | if (rc < 0 && rc != -ENODATA) { |
542 | if (rc == -EOPNOTSUPP) | |
c103a91e | 543 | pr_warn("SELinux: (dev %s, type " |
29b1deb2 LT |
544 | "%s) has no security xattr handler\n", |
545 | sb->s_id, sb->s_type->name); | |
c9180a57 | 546 | else |
c103a91e | 547 | pr_warn("SELinux: (dev %s, type " |
29b1deb2 LT |
548 | "%s) getxattr errno %d\n", sb->s_id, |
549 | sb->s_type->name, -rc); | |
c9180a57 EP |
550 | goto out; |
551 | } | |
552 | } | |
1da177e4 | 553 | |
eadcabc6 | 554 | sbsec->flags |= SE_SBINITIALIZED; |
0b4d3452 SM |
555 | |
556 | /* | |
557 | * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply | |
558 | * leave the flag untouched because sb_clone_mnt_opts might be handing | |
559 | * us a superblock that needs the flag to be cleared. | |
560 | */ | |
b43e725d | 561 | if (selinux_is_sblabel_mnt(sb)) |
12f348b9 | 562 | sbsec->flags |= SBLABEL_MNT; |
0b4d3452 SM |
563 | else |
564 | sbsec->flags &= ~SBLABEL_MNT; | |
ddd29ec6 | 565 | |
c9180a57 EP |
566 | /* Initialize the root inode. */ |
567 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 568 | |
c9180a57 EP |
569 | /* Initialize any other inodes associated with the superblock, e.g. |
570 | inodes created prior to initial policy load or inodes created | |
571 | during get_sb by a pseudo filesystem that directly | |
572 | populates itself. */ | |
573 | spin_lock(&sbsec->isec_lock); | |
574 | next_inode: | |
575 | if (!list_empty(&sbsec->isec_head)) { | |
576 | struct inode_security_struct *isec = | |
577 | list_entry(sbsec->isec_head.next, | |
578 | struct inode_security_struct, list); | |
579 | struct inode *inode = isec->inode; | |
923190d3 | 580 | list_del_init(&isec->list); |
c9180a57 EP |
581 | spin_unlock(&sbsec->isec_lock); |
582 | inode = igrab(inode); | |
583 | if (inode) { | |
584 | if (!IS_PRIVATE(inode)) | |
585 | inode_doinit(inode); | |
586 | iput(inode); | |
587 | } | |
588 | spin_lock(&sbsec->isec_lock); | |
c9180a57 EP |
589 | goto next_inode; |
590 | } | |
591 | spin_unlock(&sbsec->isec_lock); | |
592 | out: | |
593 | return rc; | |
594 | } | |
1da177e4 | 595 | |
c9180a57 EP |
596 | /* |
597 | * This function should allow an FS to ask what it's mount security | |
598 | * options were so it can use those later for submounts, displaying | |
599 | * mount options, or whatever. | |
600 | */ | |
601 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
e0007529 | 602 | struct security_mnt_opts *opts) |
c9180a57 EP |
603 | { |
604 | int rc = 0, i; | |
605 | struct superblock_security_struct *sbsec = sb->s_security; | |
606 | char *context = NULL; | |
607 | u32 len; | |
608 | char tmp; | |
1da177e4 | 609 | |
e0007529 | 610 | security_init_mnt_opts(opts); |
1da177e4 | 611 | |
0d90a7ec | 612 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
c9180a57 | 613 | return -EINVAL; |
1da177e4 | 614 | |
aa8e712c | 615 | if (!selinux_state.initialized) |
c9180a57 | 616 | return -EINVAL; |
1da177e4 | 617 | |
af8e50cc EP |
618 | /* make sure we always check enough bits to cover the mask */ |
619 | BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); | |
620 | ||
0d90a7ec | 621 | tmp = sbsec->flags & SE_MNTMASK; |
c9180a57 | 622 | /* count the number of mount options for this sb */ |
af8e50cc | 623 | for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { |
c9180a57 | 624 | if (tmp & 0x01) |
e0007529 | 625 | opts->num_mnt_opts++; |
c9180a57 EP |
626 | tmp >>= 1; |
627 | } | |
11689d47 | 628 | /* Check if the Label support flag is set */ |
0b4bdb35 | 629 | if (sbsec->flags & SBLABEL_MNT) |
11689d47 | 630 | opts->num_mnt_opts++; |
1da177e4 | 631 | |
e0007529 EP |
632 | opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); |
633 | if (!opts->mnt_opts) { | |
c9180a57 EP |
634 | rc = -ENOMEM; |
635 | goto out_free; | |
636 | } | |
1da177e4 | 637 | |
e0007529 EP |
638 | opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); |
639 | if (!opts->mnt_opts_flags) { | |
c9180a57 EP |
640 | rc = -ENOMEM; |
641 | goto out_free; | |
642 | } | |
1da177e4 | 643 | |
c9180a57 EP |
644 | i = 0; |
645 | if (sbsec->flags & FSCONTEXT_MNT) { | |
aa8e712c SS |
646 | rc = security_sid_to_context(&selinux_state, sbsec->sid, |
647 | &context, &len); | |
c9180a57 EP |
648 | if (rc) |
649 | goto out_free; | |
e0007529 EP |
650 | opts->mnt_opts[i] = context; |
651 | opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; | |
c9180a57 EP |
652 | } |
653 | if (sbsec->flags & CONTEXT_MNT) { | |
aa8e712c SS |
654 | rc = security_sid_to_context(&selinux_state, |
655 | sbsec->mntpoint_sid, | |
656 | &context, &len); | |
c9180a57 EP |
657 | if (rc) |
658 | goto out_free; | |
e0007529 EP |
659 | opts->mnt_opts[i] = context; |
660 | opts->mnt_opts_flags[i++] = CONTEXT_MNT; | |
c9180a57 EP |
661 | } |
662 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
aa8e712c SS |
663 | rc = security_sid_to_context(&selinux_state, sbsec->def_sid, |
664 | &context, &len); | |
c9180a57 EP |
665 | if (rc) |
666 | goto out_free; | |
e0007529 EP |
667 | opts->mnt_opts[i] = context; |
668 | opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
669 | } |
670 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
671 | struct dentry *root = sbsec->sb->s_root; |
672 | struct inode_security_struct *isec = backing_inode_security(root); | |
0808925e | 673 | |
aa8e712c SS |
674 | rc = security_sid_to_context(&selinux_state, isec->sid, |
675 | &context, &len); | |
c9180a57 EP |
676 | if (rc) |
677 | goto out_free; | |
e0007529 EP |
678 | opts->mnt_opts[i] = context; |
679 | opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; | |
c9180a57 | 680 | } |
12f348b9 | 681 | if (sbsec->flags & SBLABEL_MNT) { |
11689d47 | 682 | opts->mnt_opts[i] = NULL; |
12f348b9 | 683 | opts->mnt_opts_flags[i++] = SBLABEL_MNT; |
11689d47 | 684 | } |
1da177e4 | 685 | |
e0007529 | 686 | BUG_ON(i != opts->num_mnt_opts); |
1da177e4 | 687 | |
c9180a57 EP |
688 | return 0; |
689 | ||
690 | out_free: | |
e0007529 | 691 | security_free_mnt_opts(opts); |
c9180a57 EP |
692 | return rc; |
693 | } | |
1da177e4 | 694 | |
c9180a57 EP |
695 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
696 | u32 old_sid, u32 new_sid) | |
697 | { | |
0d90a7ec DQ |
698 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
699 | ||
c9180a57 | 700 | /* check if the old mount command had the same options */ |
0d90a7ec | 701 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
702 | if (!(sbsec->flags & flag) || |
703 | (old_sid != new_sid)) | |
704 | return 1; | |
705 | ||
706 | /* check if we were passed the same options twice, | |
707 | * aka someone passed context=a,context=b | |
708 | */ | |
0d90a7ec DQ |
709 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
710 | if (mnt_flags & flag) | |
c9180a57 EP |
711 | return 1; |
712 | return 0; | |
713 | } | |
e0007529 | 714 | |
c9180a57 EP |
715 | /* |
716 | * Allow filesystems with binary mount data to explicitly set mount point | |
717 | * labeling information. | |
718 | */ | |
e0007529 | 719 | static int selinux_set_mnt_opts(struct super_block *sb, |
649f6e77 DQ |
720 | struct security_mnt_opts *opts, |
721 | unsigned long kern_flags, | |
722 | unsigned long *set_kern_flags) | |
c9180a57 | 723 | { |
275bb41e | 724 | const struct cred *cred = current_cred(); |
c9180a57 | 725 | int rc = 0, i; |
c9180a57 | 726 | struct superblock_security_struct *sbsec = sb->s_security; |
29b1deb2 | 727 | const char *name = sb->s_type->name; |
83da53c5 | 728 | struct dentry *root = sbsec->sb->s_root; |
2c97165b | 729 | struct inode_security_struct *root_isec; |
c9180a57 EP |
730 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
731 | u32 defcontext_sid = 0; | |
e0007529 EP |
732 | char **mount_options = opts->mnt_opts; |
733 | int *flags = opts->mnt_opts_flags; | |
734 | int num_opts = opts->num_mnt_opts; | |
c9180a57 EP |
735 | |
736 | mutex_lock(&sbsec->lock); | |
737 | ||
aa8e712c | 738 | if (!selinux_state.initialized) { |
c9180a57 EP |
739 | if (!num_opts) { |
740 | /* Defer initialization until selinux_complete_init, | |
741 | after the initial policy is loaded and the security | |
742 | server is ready to handle calls. */ | |
c9180a57 EP |
743 | goto out; |
744 | } | |
745 | rc = -EINVAL; | |
c103a91e | 746 | pr_warn("SELinux: Unable to set superblock options " |
744ba35e | 747 | "before the security server is initialized\n"); |
1da177e4 | 748 | goto out; |
c9180a57 | 749 | } |
649f6e77 DQ |
750 | if (kern_flags && !set_kern_flags) { |
751 | /* Specifying internal flags without providing a place to | |
752 | * place the results is not allowed */ | |
753 | rc = -EINVAL; | |
754 | goto out; | |
755 | } | |
1da177e4 | 756 | |
e0007529 EP |
757 | /* |
758 | * Binary mount data FS will come through this function twice. Once | |
759 | * from an explicit call and once from the generic calls from the vfs. | |
760 | * Since the generic VFS calls will not contain any security mount data | |
761 | * we need to skip the double mount verification. | |
762 | * | |
763 | * This does open a hole in which we will not notice if the first | |
764 | * mount using this sb set explict options and a second mount using | |
765 | * this sb does not set any security options. (The first options | |
766 | * will be used for both mounts) | |
767 | */ | |
0d90a7ec | 768 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
e0007529 | 769 | && (num_opts == 0)) |
f5269710 | 770 | goto out; |
e0007529 | 771 | |
2c97165b PM |
772 | root_isec = backing_inode_security_novalidate(root); |
773 | ||
c9180a57 EP |
774 | /* |
775 | * parse the mount options, check if they are valid sids. | |
776 | * also check if someone is trying to mount the same sb more | |
777 | * than once with different security options. | |
778 | */ | |
779 | for (i = 0; i < num_opts; i++) { | |
780 | u32 sid; | |
11689d47 | 781 | |
12f348b9 | 782 | if (flags[i] == SBLABEL_MNT) |
11689d47 | 783 | continue; |
aa8e712c SS |
784 | rc = security_context_str_to_sid(&selinux_state, |
785 | mount_options[i], &sid, | |
786 | GFP_KERNEL); | |
1da177e4 | 787 | if (rc) { |
c103a91e | 788 | pr_warn("SELinux: security_context_str_to_sid" |
29b1deb2 LT |
789 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
790 | mount_options[i], sb->s_id, name, rc); | |
c9180a57 EP |
791 | goto out; |
792 | } | |
793 | switch (flags[i]) { | |
794 | case FSCONTEXT_MNT: | |
795 | fscontext_sid = sid; | |
796 | ||
797 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
798 | fscontext_sid)) | |
799 | goto out_double_mount; | |
800 | ||
801 | sbsec->flags |= FSCONTEXT_MNT; | |
802 | break; | |
803 | case CONTEXT_MNT: | |
804 | context_sid = sid; | |
805 | ||
806 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
807 | context_sid)) | |
808 | goto out_double_mount; | |
809 | ||
810 | sbsec->flags |= CONTEXT_MNT; | |
811 | break; | |
812 | case ROOTCONTEXT_MNT: | |
813 | rootcontext_sid = sid; | |
814 | ||
815 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
816 | rootcontext_sid)) | |
817 | goto out_double_mount; | |
818 | ||
819 | sbsec->flags |= ROOTCONTEXT_MNT; | |
820 | ||
821 | break; | |
822 | case DEFCONTEXT_MNT: | |
823 | defcontext_sid = sid; | |
824 | ||
825 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
826 | defcontext_sid)) | |
827 | goto out_double_mount; | |
828 | ||
829 | sbsec->flags |= DEFCONTEXT_MNT; | |
830 | ||
831 | break; | |
832 | default: | |
833 | rc = -EINVAL; | |
834 | goto out; | |
1da177e4 | 835 | } |
c9180a57 EP |
836 | } |
837 | ||
0d90a7ec | 838 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 839 | /* previously mounted with options, but not on this attempt? */ |
0d90a7ec | 840 | if ((sbsec->flags & SE_MNTMASK) && !num_opts) |
c9180a57 EP |
841 | goto out_double_mount; |
842 | rc = 0; | |
843 | goto out; | |
844 | } | |
845 | ||
089be43e | 846 | if (strcmp(sb->s_type->name, "proc") == 0) |
134509d5 SS |
847 | sbsec->flags |= SE_SBPROC | SE_SBGENFS; |
848 | ||
8e014720 | 849 | if (!strcmp(sb->s_type->name, "debugfs") || |
6a391183 | 850 | !strcmp(sb->s_type->name, "tracefs") || |
8e014720 | 851 | !strcmp(sb->s_type->name, "sysfs") || |
901ef845 AM |
852 | !strcmp(sb->s_type->name, "pstore") || |
853 | !strcmp(sb->s_type->name, "cgroup") || | |
854 | !strcmp(sb->s_type->name, "cgroup2")) | |
134509d5 | 855 | sbsec->flags |= SE_SBGENFS; |
c9180a57 | 856 | |
eb9ae686 DQ |
857 | if (!sbsec->behavior) { |
858 | /* | |
859 | * Determine the labeling behavior to use for this | |
860 | * filesystem type. | |
861 | */ | |
aa8e712c | 862 | rc = security_fs_use(&selinux_state, sb); |
eb9ae686 | 863 | if (rc) { |
c103a91e | 864 | pr_warn("%s: security_fs_use(%s) returned %d\n", |
eb9ae686 DQ |
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 | 949 | rc = -EINVAL; |
c103a91e | 950 | pr_warn("SELinux: defcontext option is " |
c9180a57 EP |
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; | |
c103a91e | 972 | pr_warn("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: | |
c103a91e | 1001 | pr_warn("SELinux: mount invalid. Same superblock, " |
094f7b69 JL |
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; | |
c103a91e | 1109 | pr_warn(SEL_MOUNT_FAIL_MSG); |
c9180a57 EP |
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; | |
c103a91e | 1122 | pr_warn(SEL_MOUNT_FAIL_MSG); |
c9180a57 EP |
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; | |
c103a91e | 1135 | pr_warn(SEL_MOUNT_FAIL_MSG); |
c9180a57 EP |
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; | |
c103a91e | 1148 | pr_warn(SEL_MOUNT_FAIL_MSG); |
c9180a57 EP |
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; | |
c103a91e | 1161 | pr_warn("SELinux: unknown mount option\n"); |
c9180a57 | 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 | } | |
1205 | ||
3583a711 AB |
1206 | static void selinux_write_opts(struct seq_file *m, |
1207 | struct security_mnt_opts *opts) | |
2069f457 EP |
1208 | { |
1209 | int i; | |
1210 | char *prefix; | |
1211 | ||
1212 | for (i = 0; i < opts->num_mnt_opts; i++) { | |
11689d47 DQ |
1213 | char *has_comma; |
1214 | ||
1215 | if (opts->mnt_opts[i]) | |
1216 | has_comma = strchr(opts->mnt_opts[i], ','); | |
1217 | else | |
1218 | has_comma = NULL; | |
2069f457 EP |
1219 | |
1220 | switch (opts->mnt_opts_flags[i]) { | |
1221 | case CONTEXT_MNT: | |
1222 | prefix = CONTEXT_STR; | |
1223 | break; | |
1224 | case FSCONTEXT_MNT: | |
1225 | prefix = FSCONTEXT_STR; | |
1226 | break; | |
1227 | case ROOTCONTEXT_MNT: | |
1228 | prefix = ROOTCONTEXT_STR; | |
1229 | break; | |
1230 | case DEFCONTEXT_MNT: | |
1231 | prefix = DEFCONTEXT_STR; | |
1232 | break; | |
12f348b9 | 1233 | case SBLABEL_MNT: |
11689d47 DQ |
1234 | seq_putc(m, ','); |
1235 | seq_puts(m, LABELSUPP_STR); | |
1236 | continue; | |
2069f457 EP |
1237 | default: |
1238 | BUG(); | |
a35c6c83 | 1239 | return; |
2069f457 EP |
1240 | }; |
1241 | /* we need a comma before each option */ | |
1242 | seq_putc(m, ','); | |
1243 | seq_puts(m, prefix); | |
1244 | if (has_comma) | |
1245 | seq_putc(m, '\"'); | |
a068acf2 | 1246 | seq_escape(m, opts->mnt_opts[i], "\"\n\\"); |
2069f457 EP |
1247 | if (has_comma) |
1248 | seq_putc(m, '\"'); | |
1249 | } | |
1250 | } | |
1251 | ||
1252 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1253 | { | |
1254 | struct security_mnt_opts opts; | |
1255 | int rc; | |
1256 | ||
1257 | rc = selinux_get_mnt_opts(sb, &opts); | |
383795c2 EP |
1258 | if (rc) { |
1259 | /* before policy load we may get EINVAL, don't show anything */ | |
1260 | if (rc == -EINVAL) | |
1261 | rc = 0; | |
2069f457 | 1262 | return rc; |
383795c2 | 1263 | } |
2069f457 EP |
1264 | |
1265 | selinux_write_opts(m, &opts); | |
1266 | ||
1267 | security_free_mnt_opts(&opts); | |
1268 | ||
1269 | return rc; | |
1270 | } | |
1271 | ||
1da177e4 LT |
1272 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1273 | { | |
1274 | switch (mode & S_IFMT) { | |
1275 | case S_IFSOCK: | |
1276 | return SECCLASS_SOCK_FILE; | |
1277 | case S_IFLNK: | |
1278 | return SECCLASS_LNK_FILE; | |
1279 | case S_IFREG: | |
1280 | return SECCLASS_FILE; | |
1281 | case S_IFBLK: | |
1282 | return SECCLASS_BLK_FILE; | |
1283 | case S_IFDIR: | |
1284 | return SECCLASS_DIR; | |
1285 | case S_IFCHR: | |
1286 | return SECCLASS_CHR_FILE; | |
1287 | case S_IFIFO: | |
1288 | return SECCLASS_FIFO_FILE; | |
1289 | ||
1290 | } | |
1291 | ||
1292 | return SECCLASS_FILE; | |
1293 | } | |
1294 | ||
13402580 JM |
1295 | static inline int default_protocol_stream(int protocol) |
1296 | { | |
1297 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1298 | } | |
1299 | ||
1300 | static inline int default_protocol_dgram(int protocol) | |
1301 | { | |
1302 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1303 | } | |
1304 | ||
1da177e4 LT |
1305 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1306 | { | |
aa8e712c | 1307 | int extsockclass = selinux_policycap_extsockclass(); |
da69a530 | 1308 | |
1da177e4 LT |
1309 | switch (family) { |
1310 | case PF_UNIX: | |
1311 | switch (type) { | |
1312 | case SOCK_STREAM: | |
1313 | case SOCK_SEQPACKET: | |
1314 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1315 | case SOCK_DGRAM: | |
2a764b52 | 1316 | case SOCK_RAW: |
1da177e4 LT |
1317 | return SECCLASS_UNIX_DGRAM_SOCKET; |
1318 | } | |
1319 | break; | |
1320 | case PF_INET: | |
1321 | case PF_INET6: | |
1322 | switch (type) { | |
1323 | case SOCK_STREAM: | |
da69a530 | 1324 | case SOCK_SEQPACKET: |
13402580 JM |
1325 | if (default_protocol_stream(protocol)) |
1326 | return SECCLASS_TCP_SOCKET; | |
da69a530 SS |
1327 | else if (extsockclass && protocol == IPPROTO_SCTP) |
1328 | return SECCLASS_SCTP_SOCKET; | |
13402580 JM |
1329 | else |
1330 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1331 | case SOCK_DGRAM: |
13402580 JM |
1332 | if (default_protocol_dgram(protocol)) |
1333 | return SECCLASS_UDP_SOCKET; | |
ef37979a SS |
1334 | else if (extsockclass && (protocol == IPPROTO_ICMP || |
1335 | protocol == IPPROTO_ICMPV6)) | |
da69a530 | 1336 | return SECCLASS_ICMP_SOCKET; |
13402580 JM |
1337 | else |
1338 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1339 | case SOCK_DCCP: |
1340 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1341 | default: |
1da177e4 LT |
1342 | return SECCLASS_RAWIP_SOCKET; |
1343 | } | |
1344 | break; | |
1345 | case PF_NETLINK: | |
1346 | switch (protocol) { | |
1347 | case NETLINK_ROUTE: | |
1348 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
7f1fb60c | 1349 | case NETLINK_SOCK_DIAG: |
1da177e4 LT |
1350 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1351 | case NETLINK_NFLOG: | |
1352 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1353 | case NETLINK_XFRM: | |
1354 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1355 | case NETLINK_SELINUX: | |
1356 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
6c6d2e9b SS |
1357 | case NETLINK_ISCSI: |
1358 | return SECCLASS_NETLINK_ISCSI_SOCKET; | |
1da177e4 LT |
1359 | case NETLINK_AUDIT: |
1360 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
6c6d2e9b SS |
1361 | case NETLINK_FIB_LOOKUP: |
1362 | return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; | |
1363 | case NETLINK_CONNECTOR: | |
1364 | return SECCLASS_NETLINK_CONNECTOR_SOCKET; | |
1365 | case NETLINK_NETFILTER: | |
1366 | return SECCLASS_NETLINK_NETFILTER_SOCKET; | |
1da177e4 LT |
1367 | case NETLINK_DNRTMSG: |
1368 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1369 | case NETLINK_KOBJECT_UEVENT: |
1370 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
6c6d2e9b SS |
1371 | case NETLINK_GENERIC: |
1372 | return SECCLASS_NETLINK_GENERIC_SOCKET; | |
1373 | case NETLINK_SCSITRANSPORT: | |
1374 | return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; | |
1375 | case NETLINK_RDMA: | |
1376 | return SECCLASS_NETLINK_RDMA_SOCKET; | |
1377 | case NETLINK_CRYPTO: | |
1378 | return SECCLASS_NETLINK_CRYPTO_SOCKET; | |
1da177e4 LT |
1379 | default: |
1380 | return SECCLASS_NETLINK_SOCKET; | |
1381 | } | |
1382 | case PF_PACKET: | |
1383 | return SECCLASS_PACKET_SOCKET; | |
1384 | case PF_KEY: | |
1385 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1386 | case PF_APPLETALK: |
1387 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1388 | } |
1389 | ||
da69a530 SS |
1390 | if (extsockclass) { |
1391 | switch (family) { | |
1392 | case PF_AX25: | |
1393 | return SECCLASS_AX25_SOCKET; | |
1394 | case PF_IPX: | |
1395 | return SECCLASS_IPX_SOCKET; | |
1396 | case PF_NETROM: | |
1397 | return SECCLASS_NETROM_SOCKET; | |
da69a530 SS |
1398 | case PF_ATMPVC: |
1399 | return SECCLASS_ATMPVC_SOCKET; | |
1400 | case PF_X25: | |
1401 | return SECCLASS_X25_SOCKET; | |
1402 | case PF_ROSE: | |
1403 | return SECCLASS_ROSE_SOCKET; | |
1404 | case PF_DECnet: | |
1405 | return SECCLASS_DECNET_SOCKET; | |
1406 | case PF_ATMSVC: | |
1407 | return SECCLASS_ATMSVC_SOCKET; | |
1408 | case PF_RDS: | |
1409 | return SECCLASS_RDS_SOCKET; | |
1410 | case PF_IRDA: | |
1411 | return SECCLASS_IRDA_SOCKET; | |
1412 | case PF_PPPOX: | |
1413 | return SECCLASS_PPPOX_SOCKET; | |
1414 | case PF_LLC: | |
1415 | return SECCLASS_LLC_SOCKET; | |
da69a530 SS |
1416 | case PF_CAN: |
1417 | return SECCLASS_CAN_SOCKET; | |
1418 | case PF_TIPC: | |
1419 | return SECCLASS_TIPC_SOCKET; | |
1420 | case PF_BLUETOOTH: | |
1421 | return SECCLASS_BLUETOOTH_SOCKET; | |
1422 | case PF_IUCV: | |
1423 | return SECCLASS_IUCV_SOCKET; | |
1424 | case PF_RXRPC: | |
1425 | return SECCLASS_RXRPC_SOCKET; | |
1426 | case PF_ISDN: | |
1427 | return SECCLASS_ISDN_SOCKET; | |
1428 | case PF_PHONET: | |
1429 | return SECCLASS_PHONET_SOCKET; | |
1430 | case PF_IEEE802154: | |
1431 | return SECCLASS_IEEE802154_SOCKET; | |
1432 | case PF_CAIF: | |
1433 | return SECCLASS_CAIF_SOCKET; | |
1434 | case PF_ALG: | |
1435 | return SECCLASS_ALG_SOCKET; | |
1436 | case PF_NFC: | |
1437 | return SECCLASS_NFC_SOCKET; | |
1438 | case PF_VSOCK: | |
1439 | return SECCLASS_VSOCK_SOCKET; | |
1440 | case PF_KCM: | |
1441 | return SECCLASS_KCM_SOCKET; | |
1442 | case PF_QIPCRTR: | |
1443 | return SECCLASS_QIPCRTR_SOCKET; | |
3051bf36 LT |
1444 | case PF_SMC: |
1445 | return SECCLASS_SMC_SOCKET; | |
68e8b849 BT |
1446 | case PF_XDP: |
1447 | return SECCLASS_XDP_SOCKET; | |
1448 | #if PF_MAX > 45 | |
da69a530 SS |
1449 | #error New address family defined, please update this function. |
1450 | #endif | |
1451 | } | |
1452 | } | |
1453 | ||
1da177e4 LT |
1454 | return SECCLASS_SOCKET; |
1455 | } | |
1456 | ||
134509d5 SS |
1457 | static int selinux_genfs_get_sid(struct dentry *dentry, |
1458 | u16 tclass, | |
1459 | u16 flags, | |
1460 | u32 *sid) | |
1da177e4 | 1461 | { |
8e6c9693 | 1462 | int rc; |
fc64005c | 1463 | struct super_block *sb = dentry->d_sb; |
8e6c9693 | 1464 | char *buffer, *path; |
1da177e4 | 1465 | |
828dfe1d | 1466 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1467 | if (!buffer) |
1468 | return -ENOMEM; | |
1469 | ||
8e6c9693 LAG |
1470 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1471 | if (IS_ERR(path)) | |
1472 | rc = PTR_ERR(path); | |
1473 | else { | |
134509d5 SS |
1474 | if (flags & SE_SBPROC) { |
1475 | /* each process gets a /proc/PID/ entry. Strip off the | |
1476 | * PID part to get a valid selinux labeling. | |
1477 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1478 | while (path[1] >= '0' && path[1] <= '9') { | |
1479 | path[1] = '/'; | |
1480 | path++; | |
1481 | } | |
8e6c9693 | 1482 | } |
aa8e712c SS |
1483 | rc = security_genfs_sid(&selinux_state, sb->s_type->name, |
1484 | path, tclass, sid); | |
7bb185ed SS |
1485 | if (rc == -ENOENT) { |
1486 | /* No match in policy, mark as unlabeled. */ | |
1487 | *sid = SECINITSID_UNLABELED; | |
1488 | rc = 0; | |
1489 | } | |
1da177e4 | 1490 | } |
1da177e4 LT |
1491 | free_page((unsigned long)buffer); |
1492 | return rc; | |
1493 | } | |
1da177e4 LT |
1494 | |
1495 | /* The inode's security attributes must be initialized before first use. */ | |
1496 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1497 | { | |
1498 | struct superblock_security_struct *sbsec = NULL; | |
1499 | struct inode_security_struct *isec = inode->i_security; | |
9287aed2 AG |
1500 | u32 task_sid, sid = 0; |
1501 | u16 sclass; | |
1da177e4 LT |
1502 | struct dentry *dentry; |
1503 | #define INITCONTEXTLEN 255 | |
1504 | char *context = NULL; | |
1505 | unsigned len = 0; | |
1506 | int rc = 0; | |
1da177e4 | 1507 | |
6f3be9f5 | 1508 | if (isec->initialized == LABEL_INITIALIZED) |
13457d07 | 1509 | return 0; |
1da177e4 | 1510 | |
9287aed2 | 1511 | spin_lock(&isec->lock); |
6f3be9f5 | 1512 | if (isec->initialized == LABEL_INITIALIZED) |
23970741 | 1513 | goto out_unlock; |
1da177e4 | 1514 | |
13457d07 AG |
1515 | if (isec->sclass == SECCLASS_FILE) |
1516 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1517 | ||
1da177e4 | 1518 | sbsec = inode->i_sb->s_security; |
0d90a7ec | 1519 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1520 | /* Defer initialization until selinux_complete_init, |
1521 | after the initial policy is loaded and the security | |
1522 | server is ready to handle calls. */ | |
1523 | spin_lock(&sbsec->isec_lock); | |
1524 | if (list_empty(&isec->list)) | |
1525 | list_add(&isec->list, &sbsec->isec_head); | |
1526 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1527 | goto out_unlock; |
1da177e4 LT |
1528 | } |
1529 | ||
9287aed2 AG |
1530 | sclass = isec->sclass; |
1531 | task_sid = isec->task_sid; | |
1532 | sid = isec->sid; | |
1533 | isec->initialized = LABEL_PENDING; | |
1534 | spin_unlock(&isec->lock); | |
1535 | ||
1da177e4 | 1536 | switch (sbsec->behavior) { |
eb9ae686 DQ |
1537 | case SECURITY_FS_USE_NATIVE: |
1538 | break; | |
1da177e4 | 1539 | case SECURITY_FS_USE_XATTR: |
5d6c3191 | 1540 | if (!(inode->i_opflags & IOP_XATTR)) { |
9287aed2 | 1541 | sid = sbsec->def_sid; |
1da177e4 LT |
1542 | break; |
1543 | } | |
1da177e4 LT |
1544 | /* Need a dentry, since the xattr API requires one. |
1545 | Life would be simpler if we could just pass the inode. */ | |
1546 | if (opt_dentry) { | |
1547 | /* Called from d_instantiate or d_splice_alias. */ | |
1548 | dentry = dget(opt_dentry); | |
1549 | } else { | |
b127125d AV |
1550 | /* |
1551 | * Called from selinux_complete_init, try to find a dentry. | |
1552 | * Some filesystems really want a connected one, so try | |
1553 | * that first. We could split SECURITY_FS_USE_XATTR in | |
1554 | * two, depending upon that... | |
1555 | */ | |
1da177e4 | 1556 | dentry = d_find_alias(inode); |
b127125d AV |
1557 | if (!dentry) |
1558 | dentry = d_find_any_alias(inode); | |
1da177e4 LT |
1559 | } |
1560 | if (!dentry) { | |
df7f54c0 EP |
1561 | /* |
1562 | * this is can be hit on boot when a file is accessed | |
1563 | * before the policy is loaded. When we load policy we | |
1564 | * may find inodes that have no dentry on the | |
1565 | * sbsec->isec_head list. No reason to complain as these | |
1566 | * will get fixed up the next time we go through | |
1567 | * inode_doinit with a dentry, before these inodes could | |
1568 | * be used again by userspace. | |
1569 | */ | |
9287aed2 | 1570 | goto out; |
1da177e4 LT |
1571 | } |
1572 | ||
1573 | len = INITCONTEXTLEN; | |
4cb912f1 | 1574 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1575 | if (!context) { |
1576 | rc = -ENOMEM; | |
1577 | dput(dentry); | |
9287aed2 | 1578 | goto out; |
1da177e4 | 1579 | } |
4cb912f1 | 1580 | context[len] = '\0'; |
5d6c3191 | 1581 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); |
1da177e4 | 1582 | if (rc == -ERANGE) { |
314dabb8 JM |
1583 | kfree(context); |
1584 | ||
1da177e4 | 1585 | /* Need a larger buffer. Query for the right size. */ |
5d6c3191 | 1586 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); |
1da177e4 LT |
1587 | if (rc < 0) { |
1588 | dput(dentry); | |
9287aed2 | 1589 | goto out; |
1da177e4 | 1590 | } |
1da177e4 | 1591 | len = rc; |
4cb912f1 | 1592 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1593 | if (!context) { |
1594 | rc = -ENOMEM; | |
1595 | dput(dentry); | |
9287aed2 | 1596 | goto out; |
1da177e4 | 1597 | } |
4cb912f1 | 1598 | context[len] = '\0'; |
5d6c3191 | 1599 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); |
1da177e4 LT |
1600 | } |
1601 | dput(dentry); | |
1602 | if (rc < 0) { | |
1603 | if (rc != -ENODATA) { | |
c103a91e | 1604 | pr_warn("SELinux: %s: getxattr returned " |
dd6f953a | 1605 | "%d for dev=%s ino=%ld\n", __func__, |
1da177e4 LT |
1606 | -rc, inode->i_sb->s_id, inode->i_ino); |
1607 | kfree(context); | |
9287aed2 | 1608 | goto out; |
1da177e4 LT |
1609 | } |
1610 | /* Map ENODATA to the default file SID */ | |
1611 | sid = sbsec->def_sid; | |
1612 | rc = 0; | |
1613 | } else { | |
aa8e712c SS |
1614 | rc = security_context_to_sid_default(&selinux_state, |
1615 | context, rc, &sid, | |
869ab514 SS |
1616 | sbsec->def_sid, |
1617 | GFP_NOFS); | |
1da177e4 | 1618 | if (rc) { |
4ba0a8ad EP |
1619 | char *dev = inode->i_sb->s_id; |
1620 | unsigned long ino = inode->i_ino; | |
1621 | ||
1622 | if (rc == -EINVAL) { | |
1623 | if (printk_ratelimit()) | |
c103a91e | 1624 | pr_notice("SELinux: inode=%lu on dev=%s was found to have an invalid " |
4ba0a8ad EP |
1625 | "context=%s. This indicates you may need to relabel the inode or the " |
1626 | "filesystem in question.\n", ino, dev, context); | |
1627 | } else { | |
c103a91e | 1628 | pr_warn("SELinux: %s: context_to_sid(%s) " |
4ba0a8ad EP |
1629 | "returned %d for dev=%s ino=%ld\n", |
1630 | __func__, context, -rc, dev, ino); | |
1631 | } | |
1da177e4 LT |
1632 | kfree(context); |
1633 | /* Leave with the unlabeled SID */ | |
1634 | rc = 0; | |
1635 | break; | |
1636 | } | |
1637 | } | |
1638 | kfree(context); | |
1da177e4 LT |
1639 | break; |
1640 | case SECURITY_FS_USE_TASK: | |
9287aed2 | 1641 | sid = task_sid; |
1da177e4 LT |
1642 | break; |
1643 | case SECURITY_FS_USE_TRANS: | |
1644 | /* Default to the fs SID. */ | |
9287aed2 | 1645 | sid = sbsec->sid; |
1da177e4 LT |
1646 | |
1647 | /* Try to obtain a transition SID. */ | |
aa8e712c SS |
1648 | rc = security_transition_sid(&selinux_state, task_sid, sid, |
1649 | sclass, NULL, &sid); | |
1da177e4 | 1650 | if (rc) |
9287aed2 | 1651 | goto out; |
1da177e4 | 1652 | break; |
c312feb2 | 1653 | case SECURITY_FS_USE_MNTPOINT: |
9287aed2 | 1654 | sid = sbsec->mntpoint_sid; |
c312feb2 | 1655 | break; |
1da177e4 | 1656 | default: |
c312feb2 | 1657 | /* Default to the fs superblock SID. */ |
9287aed2 | 1658 | sid = sbsec->sid; |
1da177e4 | 1659 | |
134509d5 | 1660 | if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) { |
f64410ec PM |
1661 | /* We must have a dentry to determine the label on |
1662 | * procfs inodes */ | |
b127125d | 1663 | if (opt_dentry) { |
f64410ec PM |
1664 | /* Called from d_instantiate or |
1665 | * d_splice_alias. */ | |
1666 | dentry = dget(opt_dentry); | |
b127125d | 1667 | } else { |
f64410ec | 1668 | /* Called from selinux_complete_init, try to |
b127125d AV |
1669 | * find a dentry. Some filesystems really want |
1670 | * a connected one, so try that first. | |
1671 | */ | |
f64410ec | 1672 | dentry = d_find_alias(inode); |
b127125d AV |
1673 | if (!dentry) |
1674 | dentry = d_find_any_alias(inode); | |
1675 | } | |
f64410ec PM |
1676 | /* |
1677 | * This can be hit on boot when a file is accessed | |
1678 | * before the policy is loaded. When we load policy we | |
1679 | * may find inodes that have no dentry on the | |
1680 | * sbsec->isec_head list. No reason to complain as | |
1681 | * these will get fixed up the next time we go through | |
1682 | * inode_doinit() with a dentry, before these inodes | |
1683 | * could be used again by userspace. | |
1684 | */ | |
1685 | if (!dentry) | |
9287aed2 AG |
1686 | goto out; |
1687 | rc = selinux_genfs_get_sid(dentry, sclass, | |
134509d5 | 1688 | sbsec->flags, &sid); |
f64410ec PM |
1689 | dput(dentry); |
1690 | if (rc) | |
9287aed2 | 1691 | goto out; |
1da177e4 LT |
1692 | } |
1693 | break; | |
1694 | } | |
1695 | ||
9287aed2 AG |
1696 | out: |
1697 | spin_lock(&isec->lock); | |
1698 | if (isec->initialized == LABEL_PENDING) { | |
1699 | if (!sid || rc) { | |
1700 | isec->initialized = LABEL_INVALID; | |
1701 | goto out_unlock; | |
1702 | } | |
1703 | ||
1704 | isec->initialized = LABEL_INITIALIZED; | |
1705 | isec->sid = sid; | |
1706 | } | |
1da177e4 | 1707 | |
23970741 | 1708 | out_unlock: |
9287aed2 | 1709 | spin_unlock(&isec->lock); |
1da177e4 LT |
1710 | return rc; |
1711 | } | |
1712 | ||
1713 | /* Convert a Linux signal to an access vector. */ | |
1714 | static inline u32 signal_to_av(int sig) | |
1715 | { | |
1716 | u32 perm = 0; | |
1717 | ||
1718 | switch (sig) { | |
1719 | case SIGCHLD: | |
1720 | /* Commonly granted from child to parent. */ | |
1721 | perm = PROCESS__SIGCHLD; | |
1722 | break; | |
1723 | case SIGKILL: | |
1724 | /* Cannot be caught or ignored */ | |
1725 | perm = PROCESS__SIGKILL; | |
1726 | break; | |
1727 | case SIGSTOP: | |
1728 | /* Cannot be caught or ignored */ | |
1729 | perm = PROCESS__SIGSTOP; | |
1730 | break; | |
1731 | default: | |
1732 | /* All other signals. */ | |
1733 | perm = PROCESS__SIGNAL; | |
1734 | break; | |
1735 | } | |
1736 | ||
1737 | return perm; | |
1738 | } | |
1739 | ||
b68e418c SS |
1740 | #if CAP_LAST_CAP > 63 |
1741 | #error Fix SELinux to handle capabilities > 63. | |
1742 | #endif | |
1743 | ||
1da177e4 | 1744 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1745 | static int cred_has_capability(const struct cred *cred, |
8e4ff6f2 | 1746 | int cap, int audit, bool initns) |
1da177e4 | 1747 | { |
2bf49690 | 1748 | struct common_audit_data ad; |
06112163 | 1749 | struct av_decision avd; |
b68e418c | 1750 | u16 sclass; |
3699c53c | 1751 | u32 sid = cred_sid(cred); |
b68e418c | 1752 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1753 | int rc; |
1da177e4 | 1754 | |
50c205f5 | 1755 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1756 | ad.u.cap = cap; |
1757 | ||
b68e418c SS |
1758 | switch (CAP_TO_INDEX(cap)) { |
1759 | case 0: | |
8e4ff6f2 | 1760 | sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; |
b68e418c SS |
1761 | break; |
1762 | case 1: | |
8e4ff6f2 | 1763 | sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; |
b68e418c SS |
1764 | break; |
1765 | default: | |
c103a91e | 1766 | pr_err("SELinux: out of range capability %d\n", cap); |
b68e418c | 1767 | BUG(); |
a35c6c83 | 1768 | return -EINVAL; |
b68e418c | 1769 | } |
06112163 | 1770 | |
6b6bc620 SS |
1771 | rc = avc_has_perm_noaudit(&selinux_state, |
1772 | sid, sid, sclass, av, 0, &avd); | |
9ade0cf4 | 1773 | if (audit == SECURITY_CAP_AUDIT) { |
6b6bc620 SS |
1774 | int rc2 = avc_audit(&selinux_state, |
1775 | sid, sid, sclass, av, &avd, rc, &ad, 0); | |
9ade0cf4 EP |
1776 | if (rc2) |
1777 | return rc2; | |
1778 | } | |
06112163 | 1779 | return rc; |
1da177e4 LT |
1780 | } |
1781 | ||
1da177e4 LT |
1782 | /* Check whether a task has a particular permission to an inode. |
1783 | The 'adp' parameter is optional and allows other audit | |
1784 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1785 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1786 | struct inode *inode, |
1787 | u32 perms, | |
19e49834 | 1788 | struct common_audit_data *adp) |
1da177e4 | 1789 | { |
1da177e4 | 1790 | struct inode_security_struct *isec; |
275bb41e | 1791 | u32 sid; |
1da177e4 | 1792 | |
e0e81739 DH |
1793 | validate_creds(cred); |
1794 | ||
828dfe1d | 1795 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1796 | return 0; |
1797 | ||
88e67f3b | 1798 | sid = cred_sid(cred); |
1da177e4 LT |
1799 | isec = inode->i_security; |
1800 | ||
6b6bc620 SS |
1801 | return avc_has_perm(&selinux_state, |
1802 | sid, isec->sid, isec->sclass, perms, adp); | |
1da177e4 LT |
1803 | } |
1804 | ||
1805 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1806 | the dentry to help the auditing code to more easily generate the | |
1807 | pathname if needed. */ | |
88e67f3b | 1808 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1809 | struct dentry *dentry, |
1810 | u32 av) | |
1811 | { | |
c6f493d6 | 1812 | struct inode *inode = d_backing_inode(dentry); |
2bf49690 | 1813 | struct common_audit_data ad; |
88e67f3b | 1814 | |
50c205f5 | 1815 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1816 | ad.u.dentry = dentry; |
5d226df4 | 1817 | __inode_security_revalidate(inode, dentry, true); |
19e49834 | 1818 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1819 | } |
1820 | ||
1821 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1822 | the path to help the auditing code to more easily generate the | |
1823 | pathname if needed. */ | |
1824 | static inline int path_has_perm(const struct cred *cred, | |
3f7036a0 | 1825 | const struct path *path, |
2875fa00 EP |
1826 | u32 av) |
1827 | { | |
c6f493d6 | 1828 | struct inode *inode = d_backing_inode(path->dentry); |
2875fa00 EP |
1829 | struct common_audit_data ad; |
1830 | ||
50c205f5 | 1831 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1832 | ad.u.path = *path; |
5d226df4 | 1833 | __inode_security_revalidate(inode, path->dentry, true); |
19e49834 | 1834 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1835 | } |
1836 | ||
13f8e981 DH |
1837 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1838 | static inline int file_path_has_perm(const struct cred *cred, | |
1839 | struct file *file, | |
1840 | u32 av) | |
1841 | { | |
1842 | struct common_audit_data ad; | |
1843 | ||
43af5de7 VG |
1844 | ad.type = LSM_AUDIT_DATA_FILE; |
1845 | ad.u.file = file; | |
19e49834 | 1846 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1847 | } |
1848 | ||
f66e448c CF |
1849 | #ifdef CONFIG_BPF_SYSCALL |
1850 | static int bpf_fd_pass(struct file *file, u32 sid); | |
1851 | #endif | |
1852 | ||
1da177e4 LT |
1853 | /* Check whether a task can use an open file descriptor to |
1854 | access an inode in a given way. Check access to the | |
1855 | descriptor itself, and then use dentry_has_perm to | |
1856 | check a particular permission to the file. | |
1857 | Access to the descriptor is implicitly granted if it | |
1858 | has the same SID as the process. If av is zero, then | |
1859 | access to the file is not checked, e.g. for cases | |
1860 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1861 | static int file_has_perm(const struct cred *cred, |
1862 | struct file *file, | |
1863 | u32 av) | |
1da177e4 | 1864 | { |
1da177e4 | 1865 | struct file_security_struct *fsec = file->f_security; |
496ad9aa | 1866 | struct inode *inode = file_inode(file); |
2bf49690 | 1867 | struct common_audit_data ad; |
88e67f3b | 1868 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1869 | int rc; |
1870 | ||
43af5de7 VG |
1871 | ad.type = LSM_AUDIT_DATA_FILE; |
1872 | ad.u.file = file; | |
1da177e4 | 1873 | |
275bb41e | 1874 | if (sid != fsec->sid) { |
6b6bc620 SS |
1875 | rc = avc_has_perm(&selinux_state, |
1876 | sid, fsec->sid, | |
1da177e4 LT |
1877 | SECCLASS_FD, |
1878 | FD__USE, | |
1879 | &ad); | |
1880 | if (rc) | |
88e67f3b | 1881 | goto out; |
1da177e4 LT |
1882 | } |
1883 | ||
f66e448c CF |
1884 | #ifdef CONFIG_BPF_SYSCALL |
1885 | rc = bpf_fd_pass(file, cred_sid(cred)); | |
1886 | if (rc) | |
1887 | return rc; | |
1888 | #endif | |
1889 | ||
1da177e4 | 1890 | /* av is zero if only checking access to the descriptor. */ |
88e67f3b | 1891 | rc = 0; |
1da177e4 | 1892 | if (av) |
19e49834 | 1893 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1894 | |
88e67f3b DH |
1895 | out: |
1896 | return rc; | |
1da177e4 LT |
1897 | } |
1898 | ||
c3c188b2 DH |
1899 | /* |
1900 | * Determine the label for an inode that might be unioned. | |
1901 | */ | |
c957f6df VG |
1902 | static int |
1903 | selinux_determine_inode_label(const struct task_security_struct *tsec, | |
1904 | struct inode *dir, | |
1905 | const struct qstr *name, u16 tclass, | |
1906 | u32 *_new_isid) | |
c3c188b2 DH |
1907 | { |
1908 | const struct superblock_security_struct *sbsec = dir->i_sb->s_security; | |
c3c188b2 DH |
1909 | |
1910 | if ((sbsec->flags & SE_SBINITIALIZED) && | |
1911 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { | |
1912 | *_new_isid = sbsec->mntpoint_sid; | |
1913 | } else if ((sbsec->flags & SBLABEL_MNT) && | |
1914 | tsec->create_sid) { | |
1915 | *_new_isid = tsec->create_sid; | |
1916 | } else { | |
20cdef8d | 1917 | const struct inode_security_struct *dsec = inode_security(dir); |
aa8e712c SS |
1918 | return security_transition_sid(&selinux_state, tsec->sid, |
1919 | dsec->sid, tclass, | |
c3c188b2 DH |
1920 | name, _new_isid); |
1921 | } | |
1922 | ||
1923 | return 0; | |
1924 | } | |
1925 | ||
1da177e4 LT |
1926 | /* Check whether a task can create a file. */ |
1927 | static int may_create(struct inode *dir, | |
1928 | struct dentry *dentry, | |
1929 | u16 tclass) | |
1930 | { | |
5fb49870 | 1931 | const struct task_security_struct *tsec = current_security(); |
1da177e4 LT |
1932 | struct inode_security_struct *dsec; |
1933 | struct superblock_security_struct *sbsec; | |
275bb41e | 1934 | u32 sid, newsid; |
2bf49690 | 1935 | struct common_audit_data ad; |
1da177e4 LT |
1936 | int rc; |
1937 | ||
83da53c5 | 1938 | dsec = inode_security(dir); |
1da177e4 LT |
1939 | sbsec = dir->i_sb->s_security; |
1940 | ||
275bb41e | 1941 | sid = tsec->sid; |
275bb41e | 1942 | |
50c205f5 | 1943 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1944 | ad.u.dentry = dentry; |
1da177e4 | 1945 | |
6b6bc620 SS |
1946 | rc = avc_has_perm(&selinux_state, |
1947 | sid, dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
1948 | DIR__ADD_NAME | DIR__SEARCH, |
1949 | &ad); | |
1950 | if (rc) | |
1951 | return rc; | |
1952 | ||
c957f6df VG |
1953 | rc = selinux_determine_inode_label(current_security(), dir, |
1954 | &dentry->d_name, tclass, &newsid); | |
c3c188b2 DH |
1955 | if (rc) |
1956 | return rc; | |
1da177e4 | 1957 | |
6b6bc620 SS |
1958 | rc = avc_has_perm(&selinux_state, |
1959 | sid, newsid, tclass, FILE__CREATE, &ad); | |
1da177e4 LT |
1960 | if (rc) |
1961 | return rc; | |
1962 | ||
6b6bc620 SS |
1963 | return avc_has_perm(&selinux_state, |
1964 | newsid, sbsec->sid, | |
1da177e4 LT |
1965 | SECCLASS_FILESYSTEM, |
1966 | FILESYSTEM__ASSOCIATE, &ad); | |
1967 | } | |
1968 | ||
828dfe1d EP |
1969 | #define MAY_LINK 0 |
1970 | #define MAY_UNLINK 1 | |
1971 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1972 | |
1973 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1974 | static int may_link(struct inode *dir, | |
1975 | struct dentry *dentry, | |
1976 | int kind) | |
1977 | ||
1978 | { | |
1da177e4 | 1979 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 1980 | struct common_audit_data ad; |
275bb41e | 1981 | u32 sid = current_sid(); |
1da177e4 LT |
1982 | u32 av; |
1983 | int rc; | |
1984 | ||
83da53c5 AG |
1985 | dsec = inode_security(dir); |
1986 | isec = backing_inode_security(dentry); | |
1da177e4 | 1987 | |
50c205f5 | 1988 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1989 | ad.u.dentry = dentry; |
1da177e4 LT |
1990 | |
1991 | av = DIR__SEARCH; | |
1992 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
6b6bc620 SS |
1993 | rc = avc_has_perm(&selinux_state, |
1994 | sid, dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
1995 | if (rc) |
1996 | return rc; | |
1997 | ||
1998 | switch (kind) { | |
1999 | case MAY_LINK: | |
2000 | av = FILE__LINK; | |
2001 | break; | |
2002 | case MAY_UNLINK: | |
2003 | av = FILE__UNLINK; | |
2004 | break; | |
2005 | case MAY_RMDIR: | |
2006 | av = DIR__RMDIR; | |
2007 | break; | |
2008 | default: | |
c103a91e | 2009 | pr_warn("SELinux: %s: unrecognized kind %d\n", |
744ba35e | 2010 | __func__, kind); |
1da177e4 LT |
2011 | return 0; |
2012 | } | |
2013 | ||
6b6bc620 SS |
2014 | rc = avc_has_perm(&selinux_state, |
2015 | sid, isec->sid, isec->sclass, av, &ad); | |
1da177e4 LT |
2016 | return rc; |
2017 | } | |
2018 | ||
2019 | static inline int may_rename(struct inode *old_dir, | |
2020 | struct dentry *old_dentry, | |
2021 | struct inode *new_dir, | |
2022 | struct dentry *new_dentry) | |
2023 | { | |
1da177e4 | 2024 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 2025 | struct common_audit_data ad; |
275bb41e | 2026 | u32 sid = current_sid(); |
1da177e4 LT |
2027 | u32 av; |
2028 | int old_is_dir, new_is_dir; | |
2029 | int rc; | |
2030 | ||
83da53c5 AG |
2031 | old_dsec = inode_security(old_dir); |
2032 | old_isec = backing_inode_security(old_dentry); | |
e36cb0b8 | 2033 | old_is_dir = d_is_dir(old_dentry); |
83da53c5 | 2034 | new_dsec = inode_security(new_dir); |
1da177e4 | 2035 | |
50c205f5 | 2036 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 2037 | |
a269434d | 2038 | ad.u.dentry = old_dentry; |
6b6bc620 SS |
2039 | rc = avc_has_perm(&selinux_state, |
2040 | sid, old_dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
2041 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
2042 | if (rc) | |
2043 | return rc; | |
6b6bc620 SS |
2044 | rc = avc_has_perm(&selinux_state, |
2045 | sid, old_isec->sid, | |
1da177e4 LT |
2046 | old_isec->sclass, FILE__RENAME, &ad); |
2047 | if (rc) | |
2048 | return rc; | |
2049 | if (old_is_dir && new_dir != old_dir) { | |
6b6bc620 SS |
2050 | rc = avc_has_perm(&selinux_state, |
2051 | sid, old_isec->sid, | |
1da177e4 LT |
2052 | old_isec->sclass, DIR__REPARENT, &ad); |
2053 | if (rc) | |
2054 | return rc; | |
2055 | } | |
2056 | ||
a269434d | 2057 | ad.u.dentry = new_dentry; |
1da177e4 | 2058 | av = DIR__ADD_NAME | DIR__SEARCH; |
2c616d4d | 2059 | if (d_is_positive(new_dentry)) |
1da177e4 | 2060 | av |= DIR__REMOVE_NAME; |
6b6bc620 SS |
2061 | rc = avc_has_perm(&selinux_state, |
2062 | sid, new_dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
2063 | if (rc) |
2064 | return rc; | |
2c616d4d | 2065 | if (d_is_positive(new_dentry)) { |
83da53c5 | 2066 | new_isec = backing_inode_security(new_dentry); |
e36cb0b8 | 2067 | new_is_dir = d_is_dir(new_dentry); |
6b6bc620 SS |
2068 | rc = avc_has_perm(&selinux_state, |
2069 | sid, new_isec->sid, | |
1da177e4 LT |
2070 | new_isec->sclass, |
2071 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
2072 | if (rc) | |
2073 | return rc; | |
2074 | } | |
2075 | ||
2076 | return 0; | |
2077 | } | |
2078 | ||
2079 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 2080 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
2081 | struct super_block *sb, |
2082 | u32 perms, | |
2bf49690 | 2083 | struct common_audit_data *ad) |
1da177e4 | 2084 | { |
1da177e4 | 2085 | struct superblock_security_struct *sbsec; |
88e67f3b | 2086 | u32 sid = cred_sid(cred); |
1da177e4 | 2087 | |
1da177e4 | 2088 | sbsec = sb->s_security; |
6b6bc620 SS |
2089 | return avc_has_perm(&selinux_state, |
2090 | sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); | |
1da177e4 LT |
2091 | } |
2092 | ||
2093 | /* Convert a Linux mode and permission mask to an access vector. */ | |
2094 | static inline u32 file_mask_to_av(int mode, int mask) | |
2095 | { | |
2096 | u32 av = 0; | |
2097 | ||
dba19c60 | 2098 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
2099 | if (mask & MAY_EXEC) |
2100 | av |= FILE__EXECUTE; | |
2101 | if (mask & MAY_READ) | |
2102 | av |= FILE__READ; | |
2103 | ||
2104 | if (mask & MAY_APPEND) | |
2105 | av |= FILE__APPEND; | |
2106 | else if (mask & MAY_WRITE) | |
2107 | av |= FILE__WRITE; | |
2108 | ||
2109 | } else { | |
2110 | if (mask & MAY_EXEC) | |
2111 | av |= DIR__SEARCH; | |
2112 | if (mask & MAY_WRITE) | |
2113 | av |= DIR__WRITE; | |
2114 | if (mask & MAY_READ) | |
2115 | av |= DIR__READ; | |
2116 | } | |
2117 | ||
2118 | return av; | |
2119 | } | |
2120 | ||
8b6a5a37 EP |
2121 | /* Convert a Linux file to an access vector. */ |
2122 | static inline u32 file_to_av(struct file *file) | |
2123 | { | |
2124 | u32 av = 0; | |
2125 | ||
2126 | if (file->f_mode & FMODE_READ) | |
2127 | av |= FILE__READ; | |
2128 | if (file->f_mode & FMODE_WRITE) { | |
2129 | if (file->f_flags & O_APPEND) | |
2130 | av |= FILE__APPEND; | |
2131 | else | |
2132 | av |= FILE__WRITE; | |
2133 | } | |
2134 | if (!av) { | |
2135 | /* | |
2136 | * Special file opened with flags 3 for ioctl-only use. | |
2137 | */ | |
2138 | av = FILE__IOCTL; | |
2139 | } | |
2140 | ||
2141 | return av; | |
2142 | } | |
2143 | ||
b0c636b9 | 2144 | /* |
8b6a5a37 | 2145 | * Convert a file to an access vector and include the correct open |
b0c636b9 EP |
2146 | * open permission. |
2147 | */ | |
8b6a5a37 | 2148 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 2149 | { |
8b6a5a37 | 2150 | u32 av = file_to_av(file); |
ccb54478 | 2151 | struct inode *inode = file_inode(file); |
b0c636b9 | 2152 | |
aa8e712c SS |
2153 | if (selinux_policycap_openperm() && |
2154 | inode->i_sb->s_magic != SOCKFS_MAGIC) | |
49b7b8de EP |
2155 | av |= FILE__OPEN; |
2156 | ||
b0c636b9 EP |
2157 | return av; |
2158 | } | |
2159 | ||
1da177e4 LT |
2160 | /* Hook functions begin here. */ |
2161 | ||
79af7307 SS |
2162 | static int selinux_binder_set_context_mgr(struct task_struct *mgr) |
2163 | { | |
2164 | u32 mysid = current_sid(); | |
2165 | u32 mgrsid = task_sid(mgr); | |
2166 | ||
6b6bc620 SS |
2167 | return avc_has_perm(&selinux_state, |
2168 | mysid, mgrsid, SECCLASS_BINDER, | |
79af7307 SS |
2169 | BINDER__SET_CONTEXT_MGR, NULL); |
2170 | } | |
2171 | ||
2172 | static int selinux_binder_transaction(struct task_struct *from, | |
2173 | struct task_struct *to) | |
2174 | { | |
2175 | u32 mysid = current_sid(); | |
2176 | u32 fromsid = task_sid(from); | |
2177 | u32 tosid = task_sid(to); | |
2178 | int rc; | |
2179 | ||
2180 | if (mysid != fromsid) { | |
6b6bc620 SS |
2181 | rc = avc_has_perm(&selinux_state, |
2182 | mysid, fromsid, SECCLASS_BINDER, | |
79af7307 SS |
2183 | BINDER__IMPERSONATE, NULL); |
2184 | if (rc) | |
2185 | return rc; | |
2186 | } | |
2187 | ||
6b6bc620 SS |
2188 | return avc_has_perm(&selinux_state, |
2189 | fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, | |
79af7307 SS |
2190 | NULL); |
2191 | } | |
2192 | ||
2193 | static int selinux_binder_transfer_binder(struct task_struct *from, | |
2194 | struct task_struct *to) | |
2195 | { | |
2196 | u32 fromsid = task_sid(from); | |
2197 | u32 tosid = task_sid(to); | |
2198 | ||
6b6bc620 SS |
2199 | return avc_has_perm(&selinux_state, |
2200 | fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, | |
79af7307 SS |
2201 | NULL); |
2202 | } | |
2203 | ||
2204 | static int selinux_binder_transfer_file(struct task_struct *from, | |
2205 | struct task_struct *to, | |
2206 | struct file *file) | |
2207 | { | |
2208 | u32 sid = task_sid(to); | |
2209 | struct file_security_struct *fsec = file->f_security; | |
83da53c5 | 2210 | struct dentry *dentry = file->f_path.dentry; |
20cdef8d | 2211 | struct inode_security_struct *isec; |
79af7307 SS |
2212 | struct common_audit_data ad; |
2213 | int rc; | |
2214 | ||
2215 | ad.type = LSM_AUDIT_DATA_PATH; | |
2216 | ad.u.path = file->f_path; | |
2217 | ||
2218 | if (sid != fsec->sid) { | |
6b6bc620 SS |
2219 | rc = avc_has_perm(&selinux_state, |
2220 | sid, fsec->sid, | |
79af7307 SS |
2221 | SECCLASS_FD, |
2222 | FD__USE, | |
2223 | &ad); | |
2224 | if (rc) | |
2225 | return rc; | |
2226 | } | |
2227 | ||
f66e448c CF |
2228 | #ifdef CONFIG_BPF_SYSCALL |
2229 | rc = bpf_fd_pass(file, sid); | |
2230 | if (rc) | |
2231 | return rc; | |
2232 | #endif | |
2233 | ||
83da53c5 | 2234 | if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
79af7307 SS |
2235 | return 0; |
2236 | ||
20cdef8d | 2237 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
2238 | return avc_has_perm(&selinux_state, |
2239 | sid, isec->sid, isec->sclass, file_to_av(file), | |
79af7307 SS |
2240 | &ad); |
2241 | } | |
2242 | ||
9e48858f | 2243 | static int selinux_ptrace_access_check(struct task_struct *child, |
5cd9c58f | 2244 | unsigned int mode) |
1da177e4 | 2245 | { |
be0554c9 SS |
2246 | u32 sid = current_sid(); |
2247 | u32 csid = task_sid(child); | |
2248 | ||
2249 | if (mode & PTRACE_MODE_READ) | |
6b6bc620 SS |
2250 | return avc_has_perm(&selinux_state, |
2251 | sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 | 2252 | |
6b6bc620 SS |
2253 | return avc_has_perm(&selinux_state, |
2254 | sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); | |
5cd9c58f DH |
2255 | } |
2256 | ||
2257 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
2258 | { | |
6b6bc620 SS |
2259 | return avc_has_perm(&selinux_state, |
2260 | task_sid(parent), current_sid(), SECCLASS_PROCESS, | |
be0554c9 | 2261 | PROCESS__PTRACE, NULL); |
1da177e4 LT |
2262 | } |
2263 | ||
2264 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 2265 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 | 2266 | { |
6b6bc620 SS |
2267 | return avc_has_perm(&selinux_state, |
2268 | current_sid(), task_sid(target), SECCLASS_PROCESS, | |
be0554c9 | 2269 | PROCESS__GETCAP, NULL); |
1da177e4 LT |
2270 | } |
2271 | ||
d84f4f99 DH |
2272 | static int selinux_capset(struct cred *new, const struct cred *old, |
2273 | const kernel_cap_t *effective, | |
2274 | const kernel_cap_t *inheritable, | |
2275 | const kernel_cap_t *permitted) | |
1da177e4 | 2276 | { |
6b6bc620 SS |
2277 | return avc_has_perm(&selinux_state, |
2278 | cred_sid(old), cred_sid(new), SECCLASS_PROCESS, | |
be0554c9 | 2279 | PROCESS__SETCAP, NULL); |
1da177e4 LT |
2280 | } |
2281 | ||
5626d3e8 JM |
2282 | /* |
2283 | * (This comment used to live with the selinux_task_setuid hook, | |
2284 | * which was removed). | |
2285 | * | |
2286 | * Since setuid only affects the current process, and since the SELinux | |
2287 | * controls are not based on the Linux identity attributes, SELinux does not | |
2288 | * need to control this operation. However, SELinux does control the use of | |
2289 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
2290 | */ | |
2291 | ||
6a9de491 EP |
2292 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
2293 | int cap, int audit) | |
1da177e4 | 2294 | { |
8e4ff6f2 | 2295 | return cred_has_capability(cred, cap, audit, ns == &init_user_ns); |
1da177e4 LT |
2296 | } |
2297 | ||
1da177e4 LT |
2298 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
2299 | { | |
88e67f3b | 2300 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2301 | int rc = 0; |
2302 | ||
2303 | if (!sb) | |
2304 | return 0; | |
2305 | ||
2306 | switch (cmds) { | |
828dfe1d EP |
2307 | case Q_SYNC: |
2308 | case Q_QUOTAON: | |
2309 | case Q_QUOTAOFF: | |
2310 | case Q_SETINFO: | |
2311 | case Q_SETQUOTA: | |
88e67f3b | 2312 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
2313 | break; |
2314 | case Q_GETFMT: | |
2315 | case Q_GETINFO: | |
2316 | case Q_GETQUOTA: | |
88e67f3b | 2317 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
2318 | break; |
2319 | default: | |
2320 | rc = 0; /* let the kernel handle invalid cmds */ | |
2321 | break; | |
1da177e4 LT |
2322 | } |
2323 | return rc; | |
2324 | } | |
2325 | ||
2326 | static int selinux_quota_on(struct dentry *dentry) | |
2327 | { | |
88e67f3b DH |
2328 | const struct cred *cred = current_cred(); |
2329 | ||
2875fa00 | 2330 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
2331 | } |
2332 | ||
12b3052c | 2333 | static int selinux_syslog(int type) |
1da177e4 | 2334 | { |
1da177e4 | 2335 | switch (type) { |
d78ca3cd KC |
2336 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2337 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
6b6bc620 SS |
2338 | return avc_has_perm(&selinux_state, |
2339 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2340 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); |
d78ca3cd KC |
2341 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2342 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2343 | /* Set level of messages printed to console */ | |
2344 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
6b6bc620 SS |
2345 | return avc_has_perm(&selinux_state, |
2346 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 SS |
2347 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, |
2348 | NULL); | |
1da177e4 | 2349 | } |
be0554c9 | 2350 | /* All other syslog types */ |
6b6bc620 SS |
2351 | return avc_has_perm(&selinux_state, |
2352 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2353 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); |
1da177e4 LT |
2354 | } |
2355 | ||
2356 | /* | |
2357 | * Check that a process has enough memory to allocate a new virtual | |
2358 | * mapping. 0 means there is enough memory for the allocation to | |
2359 | * succeed and -ENOMEM implies there is not. | |
2360 | * | |
1da177e4 LT |
2361 | * Do not audit the selinux permission check, as this is applied to all |
2362 | * processes that allocate mappings. | |
2363 | */ | |
34b4e4aa | 2364 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2365 | { |
2366 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2367 | |
b1d9e6b0 | 2368 | rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, |
8e4ff6f2 | 2369 | SECURITY_CAP_NOAUDIT, true); |
1da177e4 LT |
2370 | if (rc == 0) |
2371 | cap_sys_admin = 1; | |
2372 | ||
b1d9e6b0 | 2373 | return cap_sys_admin; |
1da177e4 LT |
2374 | } |
2375 | ||
2376 | /* binprm security operations */ | |
2377 | ||
be0554c9 | 2378 | static u32 ptrace_parent_sid(void) |
0c6181cb PM |
2379 | { |
2380 | u32 sid = 0; | |
2381 | struct task_struct *tracer; | |
2382 | ||
2383 | rcu_read_lock(); | |
be0554c9 | 2384 | tracer = ptrace_parent(current); |
0c6181cb PM |
2385 | if (tracer) |
2386 | sid = task_sid(tracer); | |
2387 | rcu_read_unlock(); | |
2388 | ||
2389 | return sid; | |
2390 | } | |
2391 | ||
7b0d0b40 SS |
2392 | static int check_nnp_nosuid(const struct linux_binprm *bprm, |
2393 | const struct task_security_struct *old_tsec, | |
2394 | const struct task_security_struct *new_tsec) | |
2395 | { | |
2396 | int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); | |
380cf5ba | 2397 | int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); |
7b0d0b40 | 2398 | int rc; |
af63f419 | 2399 | u32 av; |
7b0d0b40 SS |
2400 | |
2401 | if (!nnp && !nosuid) | |
2402 | return 0; /* neither NNP nor nosuid */ | |
2403 | ||
2404 | if (new_tsec->sid == old_tsec->sid) | |
2405 | return 0; /* No change in credentials */ | |
2406 | ||
2407 | /* | |
af63f419 SS |
2408 | * If the policy enables the nnp_nosuid_transition policy capability, |
2409 | * then we permit transitions under NNP or nosuid if the | |
2410 | * policy allows the corresponding permission between | |
2411 | * the old and new contexts. | |
7b0d0b40 | 2412 | */ |
aa8e712c | 2413 | if (selinux_policycap_nnp_nosuid_transition()) { |
af63f419 | 2414 | av = 0; |
7b0d0b40 | 2415 | if (nnp) |
af63f419 SS |
2416 | av |= PROCESS2__NNP_TRANSITION; |
2417 | if (nosuid) | |
2418 | av |= PROCESS2__NOSUID_TRANSITION; | |
6b6bc620 SS |
2419 | rc = avc_has_perm(&selinux_state, |
2420 | old_tsec->sid, new_tsec->sid, | |
af63f419 SS |
2421 | SECCLASS_PROCESS2, av, NULL); |
2422 | if (!rc) | |
2423 | return 0; | |
7b0d0b40 | 2424 | } |
af63f419 SS |
2425 | |
2426 | /* | |
2427 | * We also permit NNP or nosuid transitions to bounded SIDs, | |
2428 | * i.e. SIDs that are guaranteed to only be allowed a subset | |
2429 | * of the permissions of the current SID. | |
2430 | */ | |
aa8e712c SS |
2431 | rc = security_bounded_transition(&selinux_state, old_tsec->sid, |
2432 | new_tsec->sid); | |
af63f419 SS |
2433 | if (!rc) |
2434 | return 0; | |
2435 | ||
2436 | /* | |
2437 | * On failure, preserve the errno values for NNP vs nosuid. | |
2438 | * NNP: Operation not permitted for caller. | |
2439 | * nosuid: Permission denied to file. | |
2440 | */ | |
2441 | if (nnp) | |
2442 | return -EPERM; | |
2443 | return -EACCES; | |
7b0d0b40 SS |
2444 | } |
2445 | ||
a6f76f23 | 2446 | static int selinux_bprm_set_creds(struct linux_binprm *bprm) |
1da177e4 | 2447 | { |
a6f76f23 DH |
2448 | const struct task_security_struct *old_tsec; |
2449 | struct task_security_struct *new_tsec; | |
1da177e4 | 2450 | struct inode_security_struct *isec; |
2bf49690 | 2451 | struct common_audit_data ad; |
496ad9aa | 2452 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2453 | int rc; |
2454 | ||
a6f76f23 DH |
2455 | /* SELinux context only depends on initial program or script and not |
2456 | * the script interpreter */ | |
ddb4a144 | 2457 | if (bprm->called_set_creds) |
1da177e4 LT |
2458 | return 0; |
2459 | ||
a6f76f23 DH |
2460 | old_tsec = current_security(); |
2461 | new_tsec = bprm->cred->security; | |
83da53c5 | 2462 | isec = inode_security(inode); |
1da177e4 LT |
2463 | |
2464 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2465 | new_tsec->sid = old_tsec->sid; |
2466 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2467 | |
28eba5bf | 2468 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2469 | new_tsec->create_sid = 0; |
2470 | new_tsec->keycreate_sid = 0; | |
2471 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2472 | |
a6f76f23 DH |
2473 | if (old_tsec->exec_sid) { |
2474 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2475 | /* Reset exec SID on execve. */ |
a6f76f23 | 2476 | new_tsec->exec_sid = 0; |
259e5e6c | 2477 | |
7b0d0b40 SS |
2478 | /* Fail on NNP or nosuid if not an allowed transition. */ |
2479 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2480 | if (rc) | |
2481 | return rc; | |
1da177e4 LT |
2482 | } else { |
2483 | /* Check for a default transition on this program. */ | |
aa8e712c SS |
2484 | rc = security_transition_sid(&selinux_state, old_tsec->sid, |
2485 | isec->sid, SECCLASS_PROCESS, NULL, | |
652bb9b0 | 2486 | &new_tsec->sid); |
1da177e4 LT |
2487 | if (rc) |
2488 | return rc; | |
7b0d0b40 SS |
2489 | |
2490 | /* | |
2491 | * Fallback to old SID on NNP or nosuid if not an allowed | |
2492 | * transition. | |
2493 | */ | |
2494 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2495 | if (rc) | |
2496 | new_tsec->sid = old_tsec->sid; | |
1da177e4 LT |
2497 | } |
2498 | ||
43af5de7 VG |
2499 | ad.type = LSM_AUDIT_DATA_FILE; |
2500 | ad.u.file = bprm->file; | |
1da177e4 | 2501 | |
a6f76f23 | 2502 | if (new_tsec->sid == old_tsec->sid) { |
6b6bc620 SS |
2503 | rc = avc_has_perm(&selinux_state, |
2504 | old_tsec->sid, isec->sid, | |
1da177e4 LT |
2505 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2506 | if (rc) | |
2507 | return rc; | |
2508 | } else { | |
2509 | /* Check permissions for the transition. */ | |
6b6bc620 SS |
2510 | rc = avc_has_perm(&selinux_state, |
2511 | old_tsec->sid, new_tsec->sid, | |
1da177e4 LT |
2512 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2513 | if (rc) | |
2514 | return rc; | |
2515 | ||
6b6bc620 SS |
2516 | rc = avc_has_perm(&selinux_state, |
2517 | new_tsec->sid, isec->sid, | |
1da177e4 LT |
2518 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2519 | if (rc) | |
2520 | return rc; | |
2521 | ||
a6f76f23 DH |
2522 | /* Check for shared state */ |
2523 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
6b6bc620 SS |
2524 | rc = avc_has_perm(&selinux_state, |
2525 | old_tsec->sid, new_tsec->sid, | |
a6f76f23 DH |
2526 | SECCLASS_PROCESS, PROCESS__SHARE, |
2527 | NULL); | |
2528 | if (rc) | |
2529 | return -EPERM; | |
2530 | } | |
2531 | ||
2532 | /* Make sure that anyone attempting to ptrace over a task that | |
2533 | * changes its SID has the appropriate permit */ | |
9227dd2a | 2534 | if (bprm->unsafe & LSM_UNSAFE_PTRACE) { |
be0554c9 | 2535 | u32 ptsid = ptrace_parent_sid(); |
a6f76f23 | 2536 | if (ptsid != 0) { |
6b6bc620 SS |
2537 | rc = avc_has_perm(&selinux_state, |
2538 | ptsid, new_tsec->sid, | |
a6f76f23 DH |
2539 | SECCLASS_PROCESS, |
2540 | PROCESS__PTRACE, NULL); | |
2541 | if (rc) | |
2542 | return -EPERM; | |
2543 | } | |
2544 | } | |
1da177e4 | 2545 | |
a6f76f23 DH |
2546 | /* Clear any possibly unsafe personality bits on exec: */ |
2547 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
275bb41e | 2548 | |
1da177e4 LT |
2549 | /* Enable secure mode for SIDs transitions unless |
2550 | the noatsecure permission is granted between | |
2551 | the two SIDs, i.e. ahp returns 0. */ | |
6b6bc620 SS |
2552 | rc = avc_has_perm(&selinux_state, |
2553 | old_tsec->sid, new_tsec->sid, | |
62874c3a KC |
2554 | SECCLASS_PROCESS, PROCESS__NOATSECURE, |
2555 | NULL); | |
2556 | bprm->secureexec |= !!rc; | |
1da177e4 LT |
2557 | } |
2558 | ||
62874c3a | 2559 | return 0; |
1da177e4 LT |
2560 | } |
2561 | ||
c3c073f8 AV |
2562 | static int match_file(const void *p, struct file *file, unsigned fd) |
2563 | { | |
2564 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2565 | } | |
2566 | ||
1da177e4 | 2567 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2568 | static inline void flush_unauthorized_files(const struct cred *cred, |
2569 | struct files_struct *files) | |
1da177e4 | 2570 | { |
1da177e4 | 2571 | struct file *file, *devnull = NULL; |
b20c8122 | 2572 | struct tty_struct *tty; |
24ec839c | 2573 | int drop_tty = 0; |
c3c073f8 | 2574 | unsigned n; |
1da177e4 | 2575 | |
24ec839c | 2576 | tty = get_current_tty(); |
1da177e4 | 2577 | if (tty) { |
4a510969 | 2578 | spin_lock(&tty->files_lock); |
37dd0bd0 | 2579 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2580 | struct tty_file_private *file_priv; |
37dd0bd0 | 2581 | |
1da177e4 | 2582 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2583 | Use file_path_has_perm on the tty path directly |
2584 | rather than using file_has_perm, as this particular | |
2585 | open file may belong to another process and we are | |
2586 | only interested in the inode-based check here. */ | |
d996b62a NP |
2587 | file_priv = list_first_entry(&tty->tty_files, |
2588 | struct tty_file_private, list); | |
2589 | file = file_priv->file; | |
13f8e981 | 2590 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2591 | drop_tty = 1; |
1da177e4 | 2592 | } |
4a510969 | 2593 | spin_unlock(&tty->files_lock); |
452a00d2 | 2594 | tty_kref_put(tty); |
1da177e4 | 2595 | } |
98a27ba4 EB |
2596 | /* Reset controlling tty. */ |
2597 | if (drop_tty) | |
2598 | no_tty(); | |
1da177e4 LT |
2599 | |
2600 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2601 | n = iterate_fd(files, 0, match_file, cred); |
2602 | if (!n) /* none found? */ | |
2603 | return; | |
1da177e4 | 2604 | |
c3c073f8 | 2605 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2606 | if (IS_ERR(devnull)) |
2607 | devnull = NULL; | |
2608 | /* replace all the matching ones with this */ | |
2609 | do { | |
2610 | replace_fd(n - 1, devnull, 0); | |
2611 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2612 | if (devnull) | |
c3c073f8 | 2613 | fput(devnull); |
1da177e4 LT |
2614 | } |
2615 | ||
a6f76f23 DH |
2616 | /* |
2617 | * Prepare a process for imminent new credential changes due to exec | |
2618 | */ | |
2619 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2620 | { |
a6f76f23 DH |
2621 | struct task_security_struct *new_tsec; |
2622 | struct rlimit *rlim, *initrlim; | |
2623 | int rc, i; | |
d84f4f99 | 2624 | |
a6f76f23 DH |
2625 | new_tsec = bprm->cred->security; |
2626 | if (new_tsec->sid == new_tsec->osid) | |
2627 | return; | |
1da177e4 | 2628 | |
a6f76f23 DH |
2629 | /* Close files for which the new task SID is not authorized. */ |
2630 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2631 | |
a6f76f23 DH |
2632 | /* Always clear parent death signal on SID transitions. */ |
2633 | current->pdeath_signal = 0; | |
0356357c | 2634 | |
a6f76f23 DH |
2635 | /* Check whether the new SID can inherit resource limits from the old |
2636 | * SID. If not, reset all soft limits to the lower of the current | |
2637 | * task's hard limit and the init task's soft limit. | |
2638 | * | |
2639 | * Note that the setting of hard limits (even to lower them) can be | |
2640 | * controlled by the setrlimit check. The inclusion of the init task's | |
2641 | * soft limit into the computation is to avoid resetting soft limits | |
2642 | * higher than the default soft limit for cases where the default is | |
2643 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2644 | */ | |
6b6bc620 SS |
2645 | rc = avc_has_perm(&selinux_state, |
2646 | new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
a6f76f23 DH |
2647 | PROCESS__RLIMITINH, NULL); |
2648 | if (rc) { | |
eb2d55a3 ON |
2649 | /* protect against do_prlimit() */ |
2650 | task_lock(current); | |
a6f76f23 DH |
2651 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2652 | rlim = current->signal->rlim + i; | |
2653 | initrlim = init_task.signal->rlim + i; | |
2654 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2655 | } |
eb2d55a3 | 2656 | task_unlock(current); |
baa73d9e NP |
2657 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) |
2658 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2659 | } |
2660 | } | |
2661 | ||
2662 | /* | |
a6f76f23 DH |
2663 | * Clean up the process immediately after the installation of new credentials |
2664 | * due to exec | |
1da177e4 | 2665 | */ |
a6f76f23 | 2666 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2667 | { |
a6f76f23 | 2668 | const struct task_security_struct *tsec = current_security(); |
1da177e4 | 2669 | struct itimerval itimer; |
a6f76f23 | 2670 | u32 osid, sid; |
1da177e4 LT |
2671 | int rc, i; |
2672 | ||
a6f76f23 DH |
2673 | osid = tsec->osid; |
2674 | sid = tsec->sid; | |
2675 | ||
2676 | if (sid == osid) | |
1da177e4 LT |
2677 | return; |
2678 | ||
a6f76f23 DH |
2679 | /* Check whether the new SID can inherit signal state from the old SID. |
2680 | * If not, clear itimers to avoid subsequent signal generation and | |
2681 | * flush and unblock signals. | |
2682 | * | |
2683 | * This must occur _after_ the task SID has been updated so that any | |
2684 | * kill done after the flush will be checked against the new SID. | |
2685 | */ | |
6b6bc620 SS |
2686 | rc = avc_has_perm(&selinux_state, |
2687 | osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 | 2688 | if (rc) { |
baa73d9e NP |
2689 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) { |
2690 | memset(&itimer, 0, sizeof itimer); | |
2691 | for (i = 0; i < 3; i++) | |
2692 | do_setitimer(i, &itimer, NULL); | |
2693 | } | |
1da177e4 | 2694 | spin_lock_irq(¤t->sighand->siglock); |
9e7c8f8c ON |
2695 | if (!fatal_signal_pending(current)) { |
2696 | flush_sigqueue(¤t->pending); | |
2697 | flush_sigqueue(¤t->signal->shared_pending); | |
3bcac026 DH |
2698 | flush_signal_handlers(current, 1); |
2699 | sigemptyset(¤t->blocked); | |
9e7c8f8c | 2700 | recalc_sigpending(); |
3bcac026 | 2701 | } |
1da177e4 LT |
2702 | spin_unlock_irq(¤t->sighand->siglock); |
2703 | } | |
2704 | ||
a6f76f23 DH |
2705 | /* Wake up the parent if it is waiting so that it can recheck |
2706 | * wait permission to the new task SID. */ | |
ecd6de3c | 2707 | read_lock(&tasklist_lock); |
0b7570e7 | 2708 | __wake_up_parent(current, current->real_parent); |
ecd6de3c | 2709 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2710 | } |
2711 | ||
2712 | /* superblock security operations */ | |
2713 | ||
2714 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2715 | { | |
2716 | return superblock_alloc_security(sb); | |
2717 | } | |
2718 | ||
2719 | static void selinux_sb_free_security(struct super_block *sb) | |
2720 | { | |
2721 | superblock_free_security(sb); | |
2722 | } | |
2723 | ||
2724 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2725 | { | |
2726 | if (plen > olen) | |
2727 | return 0; | |
2728 | ||
2729 | return !memcmp(prefix, option, plen); | |
2730 | } | |
2731 | ||
2732 | static inline int selinux_option(char *option, int len) | |
2733 | { | |
832cbd9a EP |
2734 | return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || |
2735 | match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || | |
2736 | match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || | |
11689d47 DQ |
2737 | match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || |
2738 | match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); | |
1da177e4 LT |
2739 | } |
2740 | ||
2741 | static inline void take_option(char **to, char *from, int *first, int len) | |
2742 | { | |
2743 | if (!*first) { | |
2744 | **to = ','; | |
2745 | *to += 1; | |
3528a953 | 2746 | } else |
1da177e4 LT |
2747 | *first = 0; |
2748 | memcpy(*to, from, len); | |
2749 | *to += len; | |
2750 | } | |
2751 | ||
828dfe1d EP |
2752 | static inline void take_selinux_option(char **to, char *from, int *first, |
2753 | int len) | |
3528a953 CO |
2754 | { |
2755 | int current_size = 0; | |
2756 | ||
2757 | if (!*first) { | |
2758 | **to = '|'; | |
2759 | *to += 1; | |
828dfe1d | 2760 | } else |
3528a953 CO |
2761 | *first = 0; |
2762 | ||
2763 | while (current_size < len) { | |
2764 | if (*from != '"') { | |
2765 | **to = *from; | |
2766 | *to += 1; | |
2767 | } | |
2768 | from += 1; | |
2769 | current_size += 1; | |
2770 | } | |
2771 | } | |
2772 | ||
e0007529 | 2773 | static int selinux_sb_copy_data(char *orig, char *copy) |
1da177e4 LT |
2774 | { |
2775 | int fnosec, fsec, rc = 0; | |
2776 | char *in_save, *in_curr, *in_end; | |
2777 | char *sec_curr, *nosec_save, *nosec; | |
3528a953 | 2778 | int open_quote = 0; |
1da177e4 LT |
2779 | |
2780 | in_curr = orig; | |
2781 | sec_curr = copy; | |
2782 | ||
1da177e4 LT |
2783 | nosec = (char *)get_zeroed_page(GFP_KERNEL); |
2784 | if (!nosec) { | |
2785 | rc = -ENOMEM; | |
2786 | goto out; | |
2787 | } | |
2788 | ||
2789 | nosec_save = nosec; | |
2790 | fnosec = fsec = 1; | |
2791 | in_save = in_end = orig; | |
2792 | ||
2793 | do { | |
3528a953 CO |
2794 | if (*in_end == '"') |
2795 | open_quote = !open_quote; | |
2796 | if ((*in_end == ',' && open_quote == 0) || | |
2797 | *in_end == '\0') { | |
1da177e4 LT |
2798 | int len = in_end - in_curr; |
2799 | ||
2800 | if (selinux_option(in_curr, len)) | |
3528a953 | 2801 | take_selinux_option(&sec_curr, in_curr, &fsec, len); |
1da177e4 LT |
2802 | else |
2803 | take_option(&nosec, in_curr, &fnosec, len); | |
2804 | ||
2805 | in_curr = in_end + 1; | |
2806 | } | |
2807 | } while (*in_end++); | |
2808 | ||
6931dfc9 | 2809 | strcpy(in_save, nosec_save); |
da3caa20 | 2810 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
2811 | out: |
2812 | return rc; | |
2813 | } | |
2814 | ||
c039bc3c AV |
2815 | static int selinux_sb_remount(struct super_block *sb, |
2816 | struct security_mnt_opts *opts) | |
026eb167 | 2817 | { |
c039bc3c AV |
2818 | int i, *flags; |
2819 | char **mount_options; | |
026eb167 EP |
2820 | struct superblock_security_struct *sbsec = sb->s_security; |
2821 | ||
2822 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2823 | return 0; | |
2824 | ||
c039bc3c AV |
2825 | mount_options = opts->mnt_opts; |
2826 | flags = opts->mnt_opts_flags; | |
026eb167 | 2827 | |
c039bc3c | 2828 | for (i = 0; i < opts->num_mnt_opts; i++) { |
026eb167 | 2829 | u32 sid; |
c039bc3c | 2830 | int rc; |
026eb167 | 2831 | |
12f348b9 | 2832 | if (flags[i] == SBLABEL_MNT) |
026eb167 | 2833 | continue; |
aa8e712c SS |
2834 | rc = security_context_str_to_sid(&selinux_state, |
2835 | mount_options[i], &sid, | |
2836 | GFP_KERNEL); | |
026eb167 | 2837 | if (rc) { |
c103a91e | 2838 | pr_warn("SELinux: security_context_str_to_sid" |
29b1deb2 LT |
2839 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
2840 | mount_options[i], sb->s_id, sb->s_type->name, rc); | |
c039bc3c | 2841 | return rc; |
026eb167 | 2842 | } |
026eb167 EP |
2843 | switch (flags[i]) { |
2844 | case FSCONTEXT_MNT: | |
2845 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) | |
2846 | goto out_bad_option; | |
2847 | break; | |
2848 | case CONTEXT_MNT: | |
2849 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2850 | goto out_bad_option; | |
2851 | break; | |
2852 | case ROOTCONTEXT_MNT: { | |
2853 | struct inode_security_struct *root_isec; | |
83da53c5 | 2854 | root_isec = backing_inode_security(sb->s_root); |
026eb167 EP |
2855 | |
2856 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2857 | goto out_bad_option; | |
2858 | break; | |
2859 | } | |
2860 | case DEFCONTEXT_MNT: | |
2861 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2862 | goto out_bad_option; | |
2863 | break; | |
2864 | default: | |
c039bc3c | 2865 | return -EINVAL; |
026eb167 EP |
2866 | } |
2867 | } | |
c039bc3c | 2868 | return 0; |
026eb167 | 2869 | |
026eb167 | 2870 | out_bad_option: |
c103a91e | 2871 | pr_warn("SELinux: unable to change security options " |
29b1deb2 LT |
2872 | "during remount (dev %s, type=%s)\n", sb->s_id, |
2873 | sb->s_type->name); | |
c039bc3c | 2874 | return -EINVAL; |
026eb167 EP |
2875 | } |
2876 | ||
6be8750b AV |
2877 | static int selinux_sb_kern_mount(struct super_block *sb, int flags, |
2878 | struct security_mnt_opts *opts) | |
1da177e4 | 2879 | { |
88e67f3b | 2880 | const struct cred *cred = current_cred(); |
2bf49690 | 2881 | struct common_audit_data ad; |
6be8750b | 2882 | int rc = selinux_set_mnt_opts(sb, opts, 0, NULL); |
1da177e4 LT |
2883 | if (rc) |
2884 | return rc; | |
2885 | ||
74192246 JM |
2886 | /* Allow all mounts performed by the kernel */ |
2887 | if (flags & MS_KERNMOUNT) | |
2888 | return 0; | |
2889 | ||
50c205f5 | 2890 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2891 | ad.u.dentry = sb->s_root; |
88e67f3b | 2892 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2893 | } |
2894 | ||
726c3342 | 2895 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2896 | { |
88e67f3b | 2897 | const struct cred *cred = current_cred(); |
2bf49690 | 2898 | struct common_audit_data ad; |
1da177e4 | 2899 | |
50c205f5 | 2900 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2901 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2902 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2903 | } |
2904 | ||
808d4e3c | 2905 | static int selinux_mount(const char *dev_name, |
8a04c43b | 2906 | const struct path *path, |
808d4e3c | 2907 | const char *type, |
828dfe1d EP |
2908 | unsigned long flags, |
2909 | void *data) | |
1da177e4 | 2910 | { |
88e67f3b | 2911 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2912 | |
2913 | if (flags & MS_REMOUNT) | |
d8c9584e | 2914 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2915 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2916 | else |
2875fa00 | 2917 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2918 | } |
2919 | ||
2920 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2921 | { | |
88e67f3b | 2922 | const struct cred *cred = current_cred(); |
1da177e4 | 2923 | |
88e67f3b | 2924 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2925 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2926 | } |
2927 | ||
2928 | /* inode security operations */ | |
2929 | ||
2930 | static int selinux_inode_alloc_security(struct inode *inode) | |
2931 | { | |
2932 | return inode_alloc_security(inode); | |
2933 | } | |
2934 | ||
2935 | static void selinux_inode_free_security(struct inode *inode) | |
2936 | { | |
2937 | inode_free_security(inode); | |
2938 | } | |
2939 | ||
d47be3df | 2940 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
4f3ccd76 | 2941 | const struct qstr *name, void **ctx, |
d47be3df DQ |
2942 | u32 *ctxlen) |
2943 | { | |
d47be3df DQ |
2944 | u32 newsid; |
2945 | int rc; | |
2946 | ||
c957f6df VG |
2947 | rc = selinux_determine_inode_label(current_security(), |
2948 | d_inode(dentry->d_parent), name, | |
c3c188b2 DH |
2949 | inode_mode_to_security_class(mode), |
2950 | &newsid); | |
2951 | if (rc) | |
2952 | return rc; | |
d47be3df | 2953 | |
aa8e712c SS |
2954 | return security_sid_to_context(&selinux_state, newsid, (char **)ctx, |
2955 | ctxlen); | |
d47be3df DQ |
2956 | } |
2957 | ||
a518b0a5 VG |
2958 | static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, |
2959 | struct qstr *name, | |
2960 | const struct cred *old, | |
2961 | struct cred *new) | |
2962 | { | |
2963 | u32 newsid; | |
2964 | int rc; | |
2965 | struct task_security_struct *tsec; | |
2966 | ||
2967 | rc = selinux_determine_inode_label(old->security, | |
2968 | d_inode(dentry->d_parent), name, | |
2969 | inode_mode_to_security_class(mode), | |
2970 | &newsid); | |
2971 | if (rc) | |
2972 | return rc; | |
2973 | ||
2974 | tsec = new->security; | |
2975 | tsec->create_sid = newsid; | |
2976 | return 0; | |
2977 | } | |
2978 | ||
5e41ff9e | 2979 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
2980 | const struct qstr *qstr, |
2981 | const char **name, | |
2a7dba39 | 2982 | void **value, size_t *len) |
5e41ff9e | 2983 | { |
5fb49870 | 2984 | const struct task_security_struct *tsec = current_security(); |
5e41ff9e | 2985 | struct superblock_security_struct *sbsec; |
c0d4f464 | 2986 | u32 newsid, clen; |
5e41ff9e | 2987 | int rc; |
9548906b | 2988 | char *context; |
5e41ff9e | 2989 | |
5e41ff9e | 2990 | sbsec = dir->i_sb->s_security; |
5e41ff9e | 2991 | |
275bb41e DH |
2992 | newsid = tsec->create_sid; |
2993 | ||
c957f6df | 2994 | rc = selinux_determine_inode_label(current_security(), |
c3c188b2 DH |
2995 | dir, qstr, |
2996 | inode_mode_to_security_class(inode->i_mode), | |
2997 | &newsid); | |
2998 | if (rc) | |
2999 | return rc; | |
5e41ff9e | 3000 | |
296fddf7 | 3001 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 3002 | if (sbsec->flags & SE_SBINITIALIZED) { |
296fddf7 EP |
3003 | struct inode_security_struct *isec = inode->i_security; |
3004 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
3005 | isec->sid = newsid; | |
6f3be9f5 | 3006 | isec->initialized = LABEL_INITIALIZED; |
296fddf7 | 3007 | } |
5e41ff9e | 3008 | |
aa8e712c | 3009 | if (!selinux_state.initialized || !(sbsec->flags & SBLABEL_MNT)) |
25a74f3b SS |
3010 | return -EOPNOTSUPP; |
3011 | ||
9548906b TH |
3012 | if (name) |
3013 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 3014 | |
570bc1c2 | 3015 | if (value && len) { |
aa8e712c SS |
3016 | rc = security_sid_to_context_force(&selinux_state, newsid, |
3017 | &context, &clen); | |
9548906b | 3018 | if (rc) |
570bc1c2 | 3019 | return rc; |
570bc1c2 SS |
3020 | *value = context; |
3021 | *len = clen; | |
5e41ff9e | 3022 | } |
5e41ff9e | 3023 | |
5e41ff9e SS |
3024 | return 0; |
3025 | } | |
3026 | ||
4acdaf27 | 3027 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
3028 | { |
3029 | return may_create(dir, dentry, SECCLASS_FILE); | |
3030 | } | |
3031 | ||
1da177e4 LT |
3032 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
3033 | { | |
1da177e4 LT |
3034 | return may_link(dir, old_dentry, MAY_LINK); |
3035 | } | |
3036 | ||
1da177e4 LT |
3037 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
3038 | { | |
1da177e4 LT |
3039 | return may_link(dir, dentry, MAY_UNLINK); |
3040 | } | |
3041 | ||
3042 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
3043 | { | |
3044 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
3045 | } | |
3046 | ||
18bb1db3 | 3047 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
3048 | { |
3049 | return may_create(dir, dentry, SECCLASS_DIR); | |
3050 | } | |
3051 | ||
1da177e4 LT |
3052 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
3053 | { | |
3054 | return may_link(dir, dentry, MAY_RMDIR); | |
3055 | } | |
3056 | ||
1a67aafb | 3057 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 3058 | { |
1da177e4 LT |
3059 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
3060 | } | |
3061 | ||
1da177e4 | 3062 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 3063 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
3064 | { |
3065 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
3066 | } | |
3067 | ||
1da177e4 LT |
3068 | static int selinux_inode_readlink(struct dentry *dentry) |
3069 | { | |
88e67f3b DH |
3070 | const struct cred *cred = current_cred(); |
3071 | ||
2875fa00 | 3072 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
3073 | } |
3074 | ||
bda0be7a N |
3075 | static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, |
3076 | bool rcu) | |
1da177e4 | 3077 | { |
88e67f3b | 3078 | const struct cred *cred = current_cred(); |
bda0be7a N |
3079 | struct common_audit_data ad; |
3080 | struct inode_security_struct *isec; | |
3081 | u32 sid; | |
1da177e4 | 3082 | |
bda0be7a N |
3083 | validate_creds(cred); |
3084 | ||
3085 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
3086 | ad.u.dentry = dentry; | |
3087 | sid = cred_sid(cred); | |
5d226df4 AG |
3088 | isec = inode_security_rcu(inode, rcu); |
3089 | if (IS_ERR(isec)) | |
3090 | return PTR_ERR(isec); | |
bda0be7a | 3091 | |
6b6bc620 SS |
3092 | return avc_has_perm_flags(&selinux_state, |
3093 | sid, isec->sid, isec->sclass, FILE__READ, &ad, | |
bda0be7a | 3094 | rcu ? MAY_NOT_BLOCK : 0); |
1da177e4 LT |
3095 | } |
3096 | ||
d4cf970d EP |
3097 | static noinline int audit_inode_permission(struct inode *inode, |
3098 | u32 perms, u32 audited, u32 denied, | |
626b9740 | 3099 | int result, |
d4cf970d | 3100 | unsigned flags) |
1da177e4 | 3101 | { |
b782e0a6 | 3102 | struct common_audit_data ad; |
d4cf970d EP |
3103 | struct inode_security_struct *isec = inode->i_security; |
3104 | int rc; | |
3105 | ||
50c205f5 | 3106 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
3107 | ad.u.inode = inode; |
3108 | ||
6b6bc620 SS |
3109 | rc = slow_avc_audit(&selinux_state, |
3110 | current_sid(), isec->sid, isec->sclass, perms, | |
626b9740 | 3111 | audited, denied, result, &ad, flags); |
d4cf970d EP |
3112 | if (rc) |
3113 | return rc; | |
3114 | return 0; | |
3115 | } | |
3116 | ||
e74f71eb | 3117 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 3118 | { |
88e67f3b | 3119 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
3120 | u32 perms; |
3121 | bool from_access; | |
cf1dd1da | 3122 | unsigned flags = mask & MAY_NOT_BLOCK; |
2e334057 EP |
3123 | struct inode_security_struct *isec; |
3124 | u32 sid; | |
3125 | struct av_decision avd; | |
3126 | int rc, rc2; | |
3127 | u32 audited, denied; | |
1da177e4 | 3128 | |
b782e0a6 | 3129 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
3130 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
3131 | ||
b782e0a6 EP |
3132 | /* No permission to check. Existence test. */ |
3133 | if (!mask) | |
1da177e4 | 3134 | return 0; |
1da177e4 | 3135 | |
2e334057 | 3136 | validate_creds(cred); |
b782e0a6 | 3137 | |
2e334057 EP |
3138 | if (unlikely(IS_PRIVATE(inode))) |
3139 | return 0; | |
b782e0a6 EP |
3140 | |
3141 | perms = file_mask_to_av(inode->i_mode, mask); | |
3142 | ||
2e334057 | 3143 | sid = cred_sid(cred); |
5d226df4 AG |
3144 | isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK); |
3145 | if (IS_ERR(isec)) | |
3146 | return PTR_ERR(isec); | |
2e334057 | 3147 | |
6b6bc620 SS |
3148 | rc = avc_has_perm_noaudit(&selinux_state, |
3149 | sid, isec->sid, isec->sclass, perms, 0, &avd); | |
2e334057 EP |
3150 | audited = avc_audit_required(perms, &avd, rc, |
3151 | from_access ? FILE__AUDIT_ACCESS : 0, | |
3152 | &denied); | |
3153 | if (likely(!audited)) | |
3154 | return rc; | |
3155 | ||
626b9740 | 3156 | rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags); |
2e334057 EP |
3157 | if (rc2) |
3158 | return rc2; | |
3159 | return rc; | |
1da177e4 LT |
3160 | } |
3161 | ||
3162 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
3163 | { | |
88e67f3b | 3164 | const struct cred *cred = current_cred(); |
ccb54478 | 3165 | struct inode *inode = d_backing_inode(dentry); |
bc6a6008 | 3166 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 3167 | __u32 av = FILE__WRITE; |
1da177e4 | 3168 | |
bc6a6008 AW |
3169 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
3170 | if (ia_valid & ATTR_FORCE) { | |
3171 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
3172 | ATTR_FORCE); | |
3173 | if (!ia_valid) | |
3174 | return 0; | |
3175 | } | |
1da177e4 | 3176 | |
bc6a6008 AW |
3177 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
3178 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 3179 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 3180 | |
aa8e712c | 3181 | if (selinux_policycap_openperm() && |
ccb54478 SS |
3182 | inode->i_sb->s_magic != SOCKFS_MAGIC && |
3183 | (ia_valid & ATTR_SIZE) && | |
3184 | !(ia_valid & ATTR_FILE)) | |
95dbf739 EP |
3185 | av |= FILE__OPEN; |
3186 | ||
3187 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
3188 | } |
3189 | ||
3f7036a0 | 3190 | static int selinux_inode_getattr(const struct path *path) |
1da177e4 | 3191 | { |
3f7036a0 | 3192 | return path_has_perm(current_cred(), path, FILE__GETATTR); |
1da177e4 LT |
3193 | } |
3194 | ||
db59000a SS |
3195 | static bool has_cap_mac_admin(bool audit) |
3196 | { | |
3197 | const struct cred *cred = current_cred(); | |
3198 | int cap_audit = audit ? SECURITY_CAP_AUDIT : SECURITY_CAP_NOAUDIT; | |
3199 | ||
3200 | if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, cap_audit)) | |
3201 | return false; | |
3202 | if (cred_has_capability(cred, CAP_MAC_ADMIN, cap_audit, true)) | |
3203 | return false; | |
3204 | return true; | |
3205 | } | |
3206 | ||
8f0cfa52 DH |
3207 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
3208 | const void *value, size_t size, int flags) | |
1da177e4 | 3209 | { |
c6f493d6 | 3210 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3211 | struct inode_security_struct *isec; |
1da177e4 | 3212 | struct superblock_security_struct *sbsec; |
2bf49690 | 3213 | struct common_audit_data ad; |
275bb41e | 3214 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
3215 | int rc = 0; |
3216 | ||
6b240306 EB |
3217 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3218 | rc = cap_inode_setxattr(dentry, name, value, size, flags); | |
3219 | if (rc) | |
3220 | return rc; | |
3221 | ||
3222 | /* Not an attribute we recognize, so just check the | |
3223 | ordinary setattr permission. */ | |
3224 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3225 | } | |
1da177e4 LT |
3226 | |
3227 | sbsec = inode->i_sb->s_security; | |
12f348b9 | 3228 | if (!(sbsec->flags & SBLABEL_MNT)) |
1da177e4 LT |
3229 | return -EOPNOTSUPP; |
3230 | ||
2e149670 | 3231 | if (!inode_owner_or_capable(inode)) |
1da177e4 LT |
3232 | return -EPERM; |
3233 | ||
50c205f5 | 3234 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 3235 | ad.u.dentry = dentry; |
1da177e4 | 3236 | |
20cdef8d | 3237 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
3238 | rc = avc_has_perm(&selinux_state, |
3239 | sid, isec->sid, isec->sclass, | |
1da177e4 LT |
3240 | FILE__RELABELFROM, &ad); |
3241 | if (rc) | |
3242 | return rc; | |
3243 | ||
aa8e712c SS |
3244 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3245 | GFP_KERNEL); | |
12b29f34 | 3246 | if (rc == -EINVAL) { |
db59000a | 3247 | if (!has_cap_mac_admin(true)) { |
d6ea83ec EP |
3248 | struct audit_buffer *ab; |
3249 | size_t audit_size; | |
d6ea83ec EP |
3250 | |
3251 | /* We strip a nul only if it is at the end, otherwise the | |
3252 | * context contains a nul and we should audit that */ | |
e3fea3f7 | 3253 | if (value) { |
add24372 CIK |
3254 | const char *str = value; |
3255 | ||
e3fea3f7 AV |
3256 | if (str[size - 1] == '\0') |
3257 | audit_size = size - 1; | |
3258 | else | |
3259 | audit_size = size; | |
3260 | } else { | |
e3fea3f7 AV |
3261 | audit_size = 0; |
3262 | } | |
cdfb6b34 RGB |
3263 | ab = audit_log_start(audit_context(), |
3264 | GFP_ATOMIC, AUDIT_SELINUX_ERR); | |
d6ea83ec EP |
3265 | audit_log_format(ab, "op=setxattr invalid_context="); |
3266 | audit_log_n_untrustedstring(ab, value, audit_size); | |
3267 | audit_log_end(ab); | |
3268 | ||
12b29f34 | 3269 | return rc; |
d6ea83ec | 3270 | } |
aa8e712c SS |
3271 | rc = security_context_to_sid_force(&selinux_state, value, |
3272 | size, &newsid); | |
12b29f34 | 3273 | } |
1da177e4 LT |
3274 | if (rc) |
3275 | return rc; | |
3276 | ||
6b6bc620 SS |
3277 | rc = avc_has_perm(&selinux_state, |
3278 | sid, newsid, isec->sclass, | |
1da177e4 LT |
3279 | FILE__RELABELTO, &ad); |
3280 | if (rc) | |
3281 | return rc; | |
3282 | ||
aa8e712c SS |
3283 | rc = security_validate_transition(&selinux_state, isec->sid, newsid, |
3284 | sid, isec->sclass); | |
1da177e4 LT |
3285 | if (rc) |
3286 | return rc; | |
3287 | ||
6b6bc620 SS |
3288 | return avc_has_perm(&selinux_state, |
3289 | newsid, | |
1da177e4 LT |
3290 | sbsec->sid, |
3291 | SECCLASS_FILESYSTEM, | |
3292 | FILESYSTEM__ASSOCIATE, | |
3293 | &ad); | |
3294 | } | |
3295 | ||
8f0cfa52 | 3296 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 3297 | const void *value, size_t size, |
8f0cfa52 | 3298 | int flags) |
1da177e4 | 3299 | { |
c6f493d6 | 3300 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3301 | struct inode_security_struct *isec; |
1da177e4 LT |
3302 | u32 newsid; |
3303 | int rc; | |
3304 | ||
3305 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
3306 | /* Not an attribute we recognize, so nothing to do. */ | |
3307 | return; | |
3308 | } | |
3309 | ||
aa8e712c SS |
3310 | rc = security_context_to_sid_force(&selinux_state, value, size, |
3311 | &newsid); | |
1da177e4 | 3312 | if (rc) { |
c103a91e | 3313 | pr_err("SELinux: unable to map context to SID" |
12b29f34 SS |
3314 | "for (%s, %lu), rc=%d\n", |
3315 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
3316 | return; |
3317 | } | |
3318 | ||
20cdef8d | 3319 | isec = backing_inode_security(dentry); |
9287aed2 | 3320 | spin_lock(&isec->lock); |
aa9c2669 | 3321 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3322 | isec->sid = newsid; |
6f3be9f5 | 3323 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3324 | spin_unlock(&isec->lock); |
aa9c2669 | 3325 | |
1da177e4 LT |
3326 | return; |
3327 | } | |
3328 | ||
8f0cfa52 | 3329 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 3330 | { |
88e67f3b DH |
3331 | const struct cred *cred = current_cred(); |
3332 | ||
2875fa00 | 3333 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3334 | } |
3335 | ||
828dfe1d | 3336 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 3337 | { |
88e67f3b DH |
3338 | const struct cred *cred = current_cred(); |
3339 | ||
2875fa00 | 3340 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3341 | } |
3342 | ||
8f0cfa52 | 3343 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 3344 | { |
6b240306 EB |
3345 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3346 | int rc = cap_inode_removexattr(dentry, name); | |
3347 | if (rc) | |
3348 | return rc; | |
3349 | ||
3350 | /* Not an attribute we recognize, so just check the | |
3351 | ordinary setattr permission. */ | |
3352 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3353 | } | |
1da177e4 LT |
3354 | |
3355 | /* No one is allowed to remove a SELinux security label. | |
3356 | You can change the label, but all data must be labeled. */ | |
3357 | return -EACCES; | |
3358 | } | |
3359 | ||
d381d8a9 | 3360 | /* |
abc69bb6 | 3361 | * Copy the inode security context value to the user. |
d381d8a9 JM |
3362 | * |
3363 | * Permission check is handled by selinux_inode_getxattr hook. | |
3364 | */ | |
ea861dfd | 3365 | static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 3366 | { |
42492594 DQ |
3367 | u32 size; |
3368 | int error; | |
3369 | char *context = NULL; | |
20cdef8d | 3370 | struct inode_security_struct *isec; |
d381d8a9 | 3371 | |
8c8570fb DK |
3372 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
3373 | return -EOPNOTSUPP; | |
d381d8a9 | 3374 | |
abc69bb6 SS |
3375 | /* |
3376 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3377 | * value even if it is not defined by current policy; otherwise, | |
3378 | * use the in-core value under current policy. | |
3379 | * Use the non-auditing forms of the permission checks since | |
3380 | * getxattr may be called by unprivileged processes commonly | |
3381 | * and lack of permission just means that we fall back to the | |
3382 | * in-core context value, not a denial. | |
3383 | */ | |
20cdef8d | 3384 | isec = inode_security(inode); |
db59000a | 3385 | if (has_cap_mac_admin(false)) |
aa8e712c SS |
3386 | error = security_sid_to_context_force(&selinux_state, |
3387 | isec->sid, &context, | |
abc69bb6 SS |
3388 | &size); |
3389 | else | |
aa8e712c SS |
3390 | error = security_sid_to_context(&selinux_state, isec->sid, |
3391 | &context, &size); | |
42492594 DQ |
3392 | if (error) |
3393 | return error; | |
3394 | error = size; | |
3395 | if (alloc) { | |
3396 | *buffer = context; | |
3397 | goto out_nofree; | |
3398 | } | |
3399 | kfree(context); | |
3400 | out_nofree: | |
3401 | return error; | |
1da177e4 LT |
3402 | } |
3403 | ||
3404 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 3405 | const void *value, size_t size, int flags) |
1da177e4 | 3406 | { |
2c97165b | 3407 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
1da177e4 LT |
3408 | u32 newsid; |
3409 | int rc; | |
3410 | ||
3411 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3412 | return -EOPNOTSUPP; | |
3413 | ||
3414 | if (!value || !size) | |
3415 | return -EACCES; | |
3416 | ||
aa8e712c SS |
3417 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3418 | GFP_KERNEL); | |
1da177e4 LT |
3419 | if (rc) |
3420 | return rc; | |
3421 | ||
9287aed2 | 3422 | spin_lock(&isec->lock); |
aa9c2669 | 3423 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3424 | isec->sid = newsid; |
6f3be9f5 | 3425 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3426 | spin_unlock(&isec->lock); |
1da177e4 LT |
3427 | return 0; |
3428 | } | |
3429 | ||
3430 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3431 | { | |
3432 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3433 | if (buffer && len <= buffer_size) | |
3434 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3435 | return len; | |
3436 | } | |
3437 | ||
d6335d77 | 3438 | static void selinux_inode_getsecid(struct inode *inode, u32 *secid) |
713a04ae | 3439 | { |
e817c2f3 | 3440 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
713a04ae AD |
3441 | *secid = isec->sid; |
3442 | } | |
3443 | ||
56909eb3 VG |
3444 | static int selinux_inode_copy_up(struct dentry *src, struct cred **new) |
3445 | { | |
3446 | u32 sid; | |
3447 | struct task_security_struct *tsec; | |
3448 | struct cred *new_creds = *new; | |
3449 | ||
3450 | if (new_creds == NULL) { | |
3451 | new_creds = prepare_creds(); | |
3452 | if (!new_creds) | |
3453 | return -ENOMEM; | |
3454 | } | |
3455 | ||
3456 | tsec = new_creds->security; | |
3457 | /* Get label from overlay inode and set it in create_sid */ | |
3458 | selinux_inode_getsecid(d_inode(src), &sid); | |
3459 | tsec->create_sid = sid; | |
3460 | *new = new_creds; | |
3461 | return 0; | |
3462 | } | |
3463 | ||
19472b69 VG |
3464 | static int selinux_inode_copy_up_xattr(const char *name) |
3465 | { | |
3466 | /* The copy_up hook above sets the initial context on an inode, but we | |
3467 | * don't then want to overwrite it by blindly copying all the lower | |
3468 | * xattrs up. Instead, we have to filter out SELinux-related xattrs. | |
3469 | */ | |
3470 | if (strcmp(name, XATTR_NAME_SELINUX) == 0) | |
3471 | return 1; /* Discard */ | |
3472 | /* | |
3473 | * Any other attribute apart from SELINUX is not claimed, supported | |
3474 | * by selinux. | |
3475 | */ | |
3476 | return -EOPNOTSUPP; | |
3477 | } | |
3478 | ||
1da177e4 LT |
3479 | /* file security operations */ |
3480 | ||
788e7dd4 | 3481 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3482 | { |
88e67f3b | 3483 | const struct cred *cred = current_cred(); |
496ad9aa | 3484 | struct inode *inode = file_inode(file); |
1da177e4 | 3485 | |
1da177e4 LT |
3486 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3487 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3488 | mask |= MAY_APPEND; | |
3489 | ||
389fb800 PM |
3490 | return file_has_perm(cred, file, |
3491 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3492 | } |
3493 | ||
788e7dd4 YN |
3494 | static int selinux_file_permission(struct file *file, int mask) |
3495 | { | |
496ad9aa | 3496 | struct inode *inode = file_inode(file); |
20dda18b | 3497 | struct file_security_struct *fsec = file->f_security; |
b197367e | 3498 | struct inode_security_struct *isec; |
20dda18b SS |
3499 | u32 sid = current_sid(); |
3500 | ||
389fb800 | 3501 | if (!mask) |
788e7dd4 YN |
3502 | /* No permission to check. Existence test. */ |
3503 | return 0; | |
788e7dd4 | 3504 | |
b197367e | 3505 | isec = inode_security(inode); |
20dda18b | 3506 | if (sid == fsec->sid && fsec->isid == isec->sid && |
6b6bc620 | 3507 | fsec->pseqno == avc_policy_seqno(&selinux_state)) |
83d49856 | 3508 | /* No change since file_open check. */ |
20dda18b SS |
3509 | return 0; |
3510 | ||
788e7dd4 YN |
3511 | return selinux_revalidate_file_permission(file, mask); |
3512 | } | |
3513 | ||
1da177e4 LT |
3514 | static int selinux_file_alloc_security(struct file *file) |
3515 | { | |
3516 | return file_alloc_security(file); | |
3517 | } | |
3518 | ||
3519 | static void selinux_file_free_security(struct file *file) | |
3520 | { | |
3521 | file_free_security(file); | |
3522 | } | |
3523 | ||
fa1aa143 JVS |
3524 | /* |
3525 | * Check whether a task has the ioctl permission and cmd | |
3526 | * operation to an inode. | |
3527 | */ | |
1d2a168a | 3528 | static int ioctl_has_perm(const struct cred *cred, struct file *file, |
fa1aa143 JVS |
3529 | u32 requested, u16 cmd) |
3530 | { | |
3531 | struct common_audit_data ad; | |
3532 | struct file_security_struct *fsec = file->f_security; | |
3533 | struct inode *inode = file_inode(file); | |
20cdef8d | 3534 | struct inode_security_struct *isec; |
fa1aa143 JVS |
3535 | struct lsm_ioctlop_audit ioctl; |
3536 | u32 ssid = cred_sid(cred); | |
3537 | int rc; | |
3538 | u8 driver = cmd >> 8; | |
3539 | u8 xperm = cmd & 0xff; | |
3540 | ||
3541 | ad.type = LSM_AUDIT_DATA_IOCTL_OP; | |
3542 | ad.u.op = &ioctl; | |
3543 | ad.u.op->cmd = cmd; | |
3544 | ad.u.op->path = file->f_path; | |
3545 | ||
3546 | if (ssid != fsec->sid) { | |
6b6bc620 SS |
3547 | rc = avc_has_perm(&selinux_state, |
3548 | ssid, fsec->sid, | |
fa1aa143 JVS |
3549 | SECCLASS_FD, |
3550 | FD__USE, | |
3551 | &ad); | |
3552 | if (rc) | |
3553 | goto out; | |
3554 | } | |
3555 | ||
3556 | if (unlikely(IS_PRIVATE(inode))) | |
3557 | return 0; | |
3558 | ||
20cdef8d | 3559 | isec = inode_security(inode); |
6b6bc620 SS |
3560 | rc = avc_has_extended_perms(&selinux_state, |
3561 | ssid, isec->sid, isec->sclass, | |
3562 | requested, driver, xperm, &ad); | |
fa1aa143 JVS |
3563 | out: |
3564 | return rc; | |
3565 | } | |
3566 | ||
1da177e4 LT |
3567 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
3568 | unsigned long arg) | |
3569 | { | |
88e67f3b | 3570 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3571 | int error = 0; |
1da177e4 | 3572 | |
0b24dcb7 EP |
3573 | switch (cmd) { |
3574 | case FIONREAD: | |
3575 | /* fall through */ | |
3576 | case FIBMAP: | |
3577 | /* fall through */ | |
3578 | case FIGETBSZ: | |
3579 | /* fall through */ | |
2f99c369 | 3580 | case FS_IOC_GETFLAGS: |
0b24dcb7 | 3581 | /* fall through */ |
2f99c369 | 3582 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3583 | error = file_has_perm(cred, file, FILE__GETATTR); |
3584 | break; | |
1da177e4 | 3585 | |
2f99c369 | 3586 | case FS_IOC_SETFLAGS: |
0b24dcb7 | 3587 | /* fall through */ |
2f99c369 | 3588 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3589 | error = file_has_perm(cred, file, FILE__SETATTR); |
3590 | break; | |
3591 | ||
3592 | /* sys_ioctl() checks */ | |
3593 | case FIONBIO: | |
3594 | /* fall through */ | |
3595 | case FIOASYNC: | |
3596 | error = file_has_perm(cred, file, 0); | |
3597 | break; | |
1da177e4 | 3598 | |
0b24dcb7 EP |
3599 | case KDSKBENT: |
3600 | case KDSKBSENT: | |
6a9de491 | 3601 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
8e4ff6f2 | 3602 | SECURITY_CAP_AUDIT, true); |
0b24dcb7 EP |
3603 | break; |
3604 | ||
3605 | /* default case assumes that the command will go | |
3606 | * to the file's ioctl() function. | |
3607 | */ | |
3608 | default: | |
fa1aa143 | 3609 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
0b24dcb7 EP |
3610 | } |
3611 | return error; | |
1da177e4 LT |
3612 | } |
3613 | ||
fcaaade1 SS |
3614 | static int default_noexec; |
3615 | ||
1da177e4 LT |
3616 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3617 | { | |
88e67f3b | 3618 | const struct cred *cred = current_cred(); |
be0554c9 | 3619 | u32 sid = cred_sid(cred); |
d84f4f99 | 3620 | int rc = 0; |
88e67f3b | 3621 | |
fcaaade1 | 3622 | if (default_noexec && |
892e8cac SS |
3623 | (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || |
3624 | (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3625 | /* |
3626 | * We are making executable an anonymous mapping or a | |
3627 | * private file mapping that will also be writable. | |
3628 | * This has an additional check. | |
3629 | */ | |
6b6bc620 SS |
3630 | rc = avc_has_perm(&selinux_state, |
3631 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3632 | PROCESS__EXECMEM, NULL); |
1da177e4 | 3633 | if (rc) |
d84f4f99 | 3634 | goto error; |
1da177e4 | 3635 | } |
1da177e4 LT |
3636 | |
3637 | if (file) { | |
3638 | /* read access is always possible with a mapping */ | |
3639 | u32 av = FILE__READ; | |
3640 | ||
3641 | /* write access only matters if the mapping is shared */ | |
3642 | if (shared && (prot & PROT_WRITE)) | |
3643 | av |= FILE__WRITE; | |
3644 | ||
3645 | if (prot & PROT_EXEC) | |
3646 | av |= FILE__EXECUTE; | |
3647 | ||
88e67f3b | 3648 | return file_has_perm(cred, file, av); |
1da177e4 | 3649 | } |
d84f4f99 DH |
3650 | |
3651 | error: | |
3652 | return rc; | |
1da177e4 LT |
3653 | } |
3654 | ||
e5467859 | 3655 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3656 | { |
b1d9e6b0 | 3657 | int rc = 0; |
1da177e4 | 3658 | |
a2551df7 | 3659 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
98883bfd | 3660 | u32 sid = current_sid(); |
6b6bc620 SS |
3661 | rc = avc_has_perm(&selinux_state, |
3662 | sid, sid, SECCLASS_MEMPROTECT, | |
ed032189 | 3663 | MEMPROTECT__MMAP_ZERO, NULL); |
84336d1a EP |
3664 | } |
3665 | ||
98883bfd | 3666 | return rc; |
e5467859 | 3667 | } |
1da177e4 | 3668 | |
e5467859 AV |
3669 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3670 | unsigned long prot, unsigned long flags) | |
3671 | { | |
3ba4bf5f SS |
3672 | struct common_audit_data ad; |
3673 | int rc; | |
3674 | ||
3675 | if (file) { | |
3676 | ad.type = LSM_AUDIT_DATA_FILE; | |
3677 | ad.u.file = file; | |
3678 | rc = inode_has_perm(current_cred(), file_inode(file), | |
3679 | FILE__MAP, &ad); | |
3680 | if (rc) | |
3681 | return rc; | |
3682 | } | |
3683 | ||
aa8e712c | 3684 | if (selinux_state.checkreqprot) |
1da177e4 LT |
3685 | prot = reqprot; |
3686 | ||
3687 | return file_map_prot_check(file, prot, | |
3688 | (flags & MAP_TYPE) == MAP_SHARED); | |
3689 | } | |
3690 | ||
3691 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3692 | unsigned long reqprot, | |
3693 | unsigned long prot) | |
3694 | { | |
88e67f3b | 3695 | const struct cred *cred = current_cred(); |
be0554c9 | 3696 | u32 sid = cred_sid(cred); |
1da177e4 | 3697 | |
aa8e712c | 3698 | if (selinux_state.checkreqprot) |
1da177e4 LT |
3699 | prot = reqprot; |
3700 | ||
fcaaade1 SS |
3701 | if (default_noexec && |
3702 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3703 | int rc = 0; |
db4c9641 SS |
3704 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3705 | vma->vm_end <= vma->vm_mm->brk) { | |
6b6bc620 SS |
3706 | rc = avc_has_perm(&selinux_state, |
3707 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3708 | PROCESS__EXECHEAP, NULL); |
db4c9641 | 3709 | } else if (!vma->vm_file && |
c2316dbf SS |
3710 | ((vma->vm_start <= vma->vm_mm->start_stack && |
3711 | vma->vm_end >= vma->vm_mm->start_stack) || | |
d17af505 | 3712 | vma_is_stack_for_current(vma))) { |
6b6bc620 SS |
3713 | rc = avc_has_perm(&selinux_state, |
3714 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3715 | PROCESS__EXECSTACK, NULL); |
db4c9641 SS |
3716 | } else if (vma->vm_file && vma->anon_vma) { |
3717 | /* | |
3718 | * We are making executable a file mapping that has | |
3719 | * had some COW done. Since pages might have been | |
3720 | * written, check ability to execute the possibly | |
3721 | * modified content. This typically should only | |
3722 | * occur for text relocations. | |
3723 | */ | |
d84f4f99 | 3724 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3725 | } |