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d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * NSA Security-Enhanced Linux (SELinux) security module | |
4 | * | |
5 | * This file contains the SELinux hook function implementations. | |
6 | * | |
7efbb60b | 7 | * Authors: Stephen Smalley, <sds@tycho.nsa.gov> |
828dfe1d EP |
8 | * Chris Vance, <cvance@nai.com> |
9 | * Wayne Salamon, <wsalamon@nai.com> | |
10 | * James Morris <jmorris@redhat.com> | |
1da177e4 LT |
11 | * |
12 | * Copyright (C) 2001,2002 Networks Associates Technology, Inc. | |
2069f457 EP |
13 | * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> |
14 | * Eric Paris <eparis@redhat.com> | |
1da177e4 | 15 | * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. |
828dfe1d | 16 | * <dgoeddel@trustedcs.com> |
ed6d76e4 | 17 | * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. |
82c21bfa | 18 | * Paul Moore <paul@paul-moore.com> |
788e7dd4 | 19 | * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. |
828dfe1d | 20 | * Yuichi Nakamura <ynakam@hitachisoft.jp> |
3a976fa6 | 21 | * Copyright (C) 2016 Mellanox Technologies |
1da177e4 LT |
22 | */ |
23 | ||
1da177e4 | 24 | #include <linux/init.h> |
0b24dcb7 | 25 | #include <linux/kd.h> |
1da177e4 | 26 | #include <linux/kernel.h> |
0d094efe | 27 | #include <linux/tracehook.h> |
1da177e4 | 28 | #include <linux/errno.h> |
3f07c014 | 29 | #include <linux/sched/signal.h> |
29930025 | 30 | #include <linux/sched/task.h> |
3c4ed7bd | 31 | #include <linux/lsm_hooks.h> |
1da177e4 LT |
32 | #include <linux/xattr.h> |
33 | #include <linux/capability.h> | |
34 | #include <linux/unistd.h> | |
35 | #include <linux/mm.h> | |
36 | #include <linux/mman.h> | |
37 | #include <linux/slab.h> | |
38 | #include <linux/pagemap.h> | |
0b24dcb7 | 39 | #include <linux/proc_fs.h> |
1da177e4 | 40 | #include <linux/swap.h> |
1da177e4 LT |
41 | #include <linux/spinlock.h> |
42 | #include <linux/syscalls.h> | |
2a7dba39 | 43 | #include <linux/dcache.h> |
1da177e4 | 44 | #include <linux/file.h> |
9f3acc31 | 45 | #include <linux/fdtable.h> |
1da177e4 LT |
46 | #include <linux/namei.h> |
47 | #include <linux/mount.h> | |
442155c1 DH |
48 | #include <linux/fs_context.h> |
49 | #include <linux/fs_parser.h> | |
1da177e4 LT |
50 | #include <linux/netfilter_ipv4.h> |
51 | #include <linux/netfilter_ipv6.h> | |
52 | #include <linux/tty.h> | |
53 | #include <net/icmp.h> | |
227b60f5 | 54 | #include <net/ip.h> /* for local_port_range[] */ |
1da177e4 | 55 | #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ |
47180068 | 56 | #include <net/inet_connection_sock.h> |
220deb96 | 57 | #include <net/net_namespace.h> |
d621d35e | 58 | #include <net/netlabel.h> |
f5269710 | 59 | #include <linux/uaccess.h> |
1da177e4 | 60 | #include <asm/ioctls.h> |
60063497 | 61 | #include <linux/atomic.h> |
1da177e4 LT |
62 | #include <linux/bitops.h> |
63 | #include <linux/interrupt.h> | |
64 | #include <linux/netdevice.h> /* for network interface checks */ | |
77954983 | 65 | #include <net/netlink.h> |
1da177e4 LT |
66 | #include <linux/tcp.h> |
67 | #include <linux/udp.h> | |
2ee92d46 | 68 | #include <linux/dccp.h> |
d452930f RH |
69 | #include <linux/sctp.h> |
70 | #include <net/sctp/structs.h> | |
1da177e4 LT |
71 | #include <linux/quota.h> |
72 | #include <linux/un.h> /* for Unix socket types */ | |
73 | #include <net/af_unix.h> /* for Unix socket types */ | |
74 | #include <linux/parser.h> | |
75 | #include <linux/nfs_mount.h> | |
76 | #include <net/ipv6.h> | |
77 | #include <linux/hugetlb.h> | |
78 | #include <linux/personality.h> | |
1da177e4 | 79 | #include <linux/audit.h> |
6931dfc9 | 80 | #include <linux/string.h> |
23970741 | 81 | #include <linux/mutex.h> |
f06febc9 | 82 | #include <linux/posix-timers.h> |
00234592 | 83 | #include <linux/syslog.h> |
3486740a | 84 | #include <linux/user_namespace.h> |
44fc7ea0 | 85 | #include <linux/export.h> |
40401530 AV |
86 | #include <linux/msg.h> |
87 | #include <linux/shm.h> | |
ec27c356 | 88 | #include <linux/bpf.h> |
ec882da5 OM |
89 | #include <linux/kernfs.h> |
90 | #include <linux/stringhash.h> /* for hashlen_string() */ | |
e262e32d | 91 | #include <uapi/linux/mount.h> |
ac5656d8 AG |
92 | #include <linux/fsnotify.h> |
93 | #include <linux/fanotify.h> | |
1da177e4 LT |
94 | |
95 | #include "avc.h" | |
96 | #include "objsec.h" | |
97 | #include "netif.h" | |
224dfbd8 | 98 | #include "netnode.h" |
3e112172 | 99 | #include "netport.h" |
409dcf31 | 100 | #include "ibpkey.h" |
d28d1e08 | 101 | #include "xfrm.h" |
c60475bf | 102 | #include "netlabel.h" |
9d57a7f9 | 103 | #include "audit.h" |
7b98a585 | 104 | #include "avc_ss.h" |
1da177e4 | 105 | |
aa8e712c SS |
106 | struct selinux_state selinux_state; |
107 | ||
d621d35e | 108 | /* SECMARK reference count */ |
56a4ca99 | 109 | static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); |
d621d35e | 110 | |
1da177e4 | 111 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
aa8e712c | 112 | static int selinux_enforcing_boot; |
1da177e4 LT |
113 | |
114 | static int __init enforcing_setup(char *str) | |
115 | { | |
f5269710 | 116 | unsigned long enforcing; |
29707b20 | 117 | if (!kstrtoul(str, 0, &enforcing)) |
aa8e712c | 118 | selinux_enforcing_boot = enforcing ? 1 : 0; |
1da177e4 LT |
119 | return 1; |
120 | } | |
121 | __setup("enforcing=", enforcing_setup); | |
aa8e712c SS |
122 | #else |
123 | #define selinux_enforcing_boot 1 | |
1da177e4 LT |
124 | #endif |
125 | ||
be6ec88f | 126 | int selinux_enabled __lsm_ro_after_init = 1; |
1da177e4 | 127 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM |
1da177e4 LT |
128 | static int __init selinux_enabled_setup(char *str) |
129 | { | |
f5269710 | 130 | unsigned long enabled; |
29707b20 | 131 | if (!kstrtoul(str, 0, &enabled)) |
f5269710 | 132 | selinux_enabled = enabled ? 1 : 0; |
1da177e4 LT |
133 | return 1; |
134 | } | |
135 | __setup("selinux=", selinux_enabled_setup); | |
136 | #endif | |
137 | ||
aa8e712c SS |
138 | static unsigned int selinux_checkreqprot_boot = |
139 | CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE; | |
140 | ||
141 | static int __init checkreqprot_setup(char *str) | |
142 | { | |
143 | unsigned long checkreqprot; | |
144 | ||
145 | if (!kstrtoul(str, 0, &checkreqprot)) | |
146 | selinux_checkreqprot_boot = checkreqprot ? 1 : 0; | |
147 | return 1; | |
148 | } | |
149 | __setup("checkreqprot=", checkreqprot_setup); | |
150 | ||
d621d35e PM |
151 | /** |
152 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
153 | * | |
154 | * Description: | |
155 | * This function checks the SECMARK reference counter to see if any SECMARK | |
156 | * targets are currently configured, if the reference counter is greater than | |
157 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
2be4d74f CP |
158 | * enabled, false (0) if SECMARK is disabled. If the always_check_network |
159 | * policy capability is enabled, SECMARK is always considered enabled. | |
d621d35e PM |
160 | * |
161 | */ | |
162 | static int selinux_secmark_enabled(void) | |
163 | { | |
aa8e712c SS |
164 | return (selinux_policycap_alwaysnetwork() || |
165 | atomic_read(&selinux_secmark_refcount)); | |
2be4d74f CP |
166 | } |
167 | ||
168 | /** | |
169 | * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled | |
170 | * | |
171 | * Description: | |
172 | * This function checks if NetLabel or labeled IPSEC is enabled. Returns true | |
173 | * (1) if any are enabled or false (0) if neither are enabled. If the | |
174 | * always_check_network policy capability is enabled, peer labeling | |
175 | * is always considered enabled. | |
176 | * | |
177 | */ | |
178 | static int selinux_peerlbl_enabled(void) | |
179 | { | |
aa8e712c SS |
180 | return (selinux_policycap_alwaysnetwork() || |
181 | netlbl_enabled() || selinux_xfrm_enabled()); | |
d621d35e PM |
182 | } |
183 | ||
615e51fd PM |
184 | static int selinux_netcache_avc_callback(u32 event) |
185 | { | |
186 | if (event == AVC_CALLBACK_RESET) { | |
187 | sel_netif_flush(); | |
188 | sel_netnode_flush(); | |
189 | sel_netport_flush(); | |
190 | synchronize_net(); | |
191 | } | |
192 | return 0; | |
193 | } | |
194 | ||
8f408ab6 DJ |
195 | static int selinux_lsm_notifier_avc_callback(u32 event) |
196 | { | |
409dcf31 DJ |
197 | if (event == AVC_CALLBACK_RESET) { |
198 | sel_ib_pkey_flush(); | |
42df744c | 199 | call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL); |
409dcf31 | 200 | } |
8f408ab6 DJ |
201 | |
202 | return 0; | |
203 | } | |
204 | ||
d84f4f99 DH |
205 | /* |
206 | * initialise the security for the init task | |
207 | */ | |
208 | static void cred_init_security(void) | |
1da177e4 | 209 | { |
3b11a1de | 210 | struct cred *cred = (struct cred *) current->real_cred; |
1da177e4 LT |
211 | struct task_security_struct *tsec; |
212 | ||
bbd3662a | 213 | tsec = selinux_cred(cred); |
d84f4f99 | 214 | tsec->osid = tsec->sid = SECINITSID_KERNEL; |
1da177e4 LT |
215 | } |
216 | ||
88e67f3b DH |
217 | /* |
218 | * get the security ID of a set of credentials | |
219 | */ | |
220 | static inline u32 cred_sid(const struct cred *cred) | |
221 | { | |
222 | const struct task_security_struct *tsec; | |
223 | ||
0c6cfa62 | 224 | tsec = selinux_cred(cred); |
88e67f3b DH |
225 | return tsec->sid; |
226 | } | |
227 | ||
275bb41e | 228 | /* |
3b11a1de | 229 | * get the objective security ID of a task |
275bb41e DH |
230 | */ |
231 | static inline u32 task_sid(const struct task_struct *task) | |
232 | { | |
275bb41e DH |
233 | u32 sid; |
234 | ||
235 | rcu_read_lock(); | |
88e67f3b | 236 | sid = cred_sid(__task_cred(task)); |
275bb41e DH |
237 | rcu_read_unlock(); |
238 | return sid; | |
239 | } | |
240 | ||
88e67f3b DH |
241 | /* Allocate and free functions for each kind of security blob. */ |
242 | ||
1da177e4 LT |
243 | static int inode_alloc_security(struct inode *inode) |
244 | { | |
afb1cbe3 | 245 | struct inode_security_struct *isec = selinux_inode(inode); |
275bb41e | 246 | u32 sid = current_sid(); |
1da177e4 | 247 | |
9287aed2 | 248 | spin_lock_init(&isec->lock); |
1da177e4 | 249 | INIT_LIST_HEAD(&isec->list); |
1da177e4 LT |
250 | isec->inode = inode; |
251 | isec->sid = SECINITSID_UNLABELED; | |
252 | isec->sclass = SECCLASS_FILE; | |
275bb41e | 253 | isec->task_sid = sid; |
42059112 | 254 | isec->initialized = LABEL_INVALID; |
1da177e4 LT |
255 | |
256 | return 0; | |
257 | } | |
258 | ||
5d226df4 AG |
259 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); |
260 | ||
261 | /* | |
262 | * Try reloading inode security labels that have been marked as invalid. The | |
263 | * @may_sleep parameter indicates when sleeping and thus reloading labels is | |
42059112 | 264 | * allowed; when set to false, returns -ECHILD when the label is |
e9193288 | 265 | * invalid. The @dentry parameter should be set to a dentry of the inode. |
5d226df4 AG |
266 | */ |
267 | static int __inode_security_revalidate(struct inode *inode, | |
e9193288 | 268 | struct dentry *dentry, |
5d226df4 AG |
269 | bool may_sleep) |
270 | { | |
80788c22 | 271 | struct inode_security_struct *isec = selinux_inode(inode); |
5d226df4 AG |
272 | |
273 | might_sleep_if(may_sleep); | |
274 | ||
aa8e712c SS |
275 | if (selinux_state.initialized && |
276 | isec->initialized != LABEL_INITIALIZED) { | |
5d226df4 AG |
277 | if (!may_sleep) |
278 | return -ECHILD; | |
279 | ||
280 | /* | |
281 | * Try reloading the inode security label. This will fail if | |
282 | * @opt_dentry is NULL and no dentry for this inode can be | |
283 | * found; in that case, continue using the old label. | |
284 | */ | |
e9193288 | 285 | inode_doinit_with_dentry(inode, dentry); |
5d226df4 AG |
286 | } |
287 | return 0; | |
288 | } | |
289 | ||
5d226df4 AG |
290 | static struct inode_security_struct *inode_security_novalidate(struct inode *inode) |
291 | { | |
80788c22 | 292 | return selinux_inode(inode); |
5d226df4 AG |
293 | } |
294 | ||
295 | static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) | |
296 | { | |
297 | int error; | |
298 | ||
299 | error = __inode_security_revalidate(inode, NULL, !rcu); | |
300 | if (error) | |
301 | return ERR_PTR(error); | |
80788c22 | 302 | return selinux_inode(inode); |
5d226df4 AG |
303 | } |
304 | ||
83da53c5 AG |
305 | /* |
306 | * Get the security label of an inode. | |
307 | */ | |
308 | static struct inode_security_struct *inode_security(struct inode *inode) | |
309 | { | |
5d226df4 | 310 | __inode_security_revalidate(inode, NULL, true); |
80788c22 | 311 | return selinux_inode(inode); |
83da53c5 AG |
312 | } |
313 | ||
2c97165b PM |
314 | static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) |
315 | { | |
316 | struct inode *inode = d_backing_inode(dentry); | |
317 | ||
80788c22 | 318 | return selinux_inode(inode); |
2c97165b PM |
319 | } |
320 | ||
83da53c5 AG |
321 | /* |
322 | * Get the security label of a dentry's backing inode. | |
323 | */ | |
324 | static struct inode_security_struct *backing_inode_security(struct dentry *dentry) | |
325 | { | |
326 | struct inode *inode = d_backing_inode(dentry); | |
327 | ||
5d226df4 | 328 | __inode_security_revalidate(inode, dentry, true); |
80788c22 | 329 | return selinux_inode(inode); |
83da53c5 AG |
330 | } |
331 | ||
1da177e4 LT |
332 | static void inode_free_security(struct inode *inode) |
333 | { | |
80788c22 | 334 | struct inode_security_struct *isec = selinux_inode(inode); |
afb1cbe3 | 335 | struct superblock_security_struct *sbsec; |
1da177e4 | 336 | |
afb1cbe3 CS |
337 | if (!isec) |
338 | return; | |
339 | sbsec = inode->i_sb->s_security; | |
9629d04a WL |
340 | /* |
341 | * As not all inode security structures are in a list, we check for | |
342 | * empty list outside of the lock to make sure that we won't waste | |
343 | * time taking a lock doing nothing. | |
344 | * | |
345 | * The list_del_init() function can be safely called more than once. | |
346 | * It should not be possible for this function to be called with | |
347 | * concurrent list_add(), but for better safety against future changes | |
348 | * in the code, we use list_empty_careful() here. | |
349 | */ | |
350 | if (!list_empty_careful(&isec->list)) { | |
351 | spin_lock(&sbsec->isec_lock); | |
1da177e4 | 352 | list_del_init(&isec->list); |
9629d04a WL |
353 | spin_unlock(&sbsec->isec_lock); |
354 | } | |
1da177e4 LT |
355 | } |
356 | ||
357 | static int file_alloc_security(struct file *file) | |
358 | { | |
33bf60ca | 359 | struct file_security_struct *fsec = selinux_file(file); |
275bb41e | 360 | u32 sid = current_sid(); |
1da177e4 | 361 | |
275bb41e DH |
362 | fsec->sid = sid; |
363 | fsec->fown_sid = sid; | |
1da177e4 LT |
364 | |
365 | return 0; | |
366 | } | |
367 | ||
1da177e4 LT |
368 | static int superblock_alloc_security(struct super_block *sb) |
369 | { | |
370 | struct superblock_security_struct *sbsec; | |
371 | ||
89d155ef | 372 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
373 | if (!sbsec) |
374 | return -ENOMEM; | |
375 | ||
bc7e982b | 376 | mutex_init(&sbsec->lock); |
1da177e4 LT |
377 | INIT_LIST_HEAD(&sbsec->isec_head); |
378 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
379 | sbsec->sb = sb; |
380 | sbsec->sid = SECINITSID_UNLABELED; | |
381 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 382 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
383 | sb->s_security = sbsec; |
384 | ||
385 | return 0; | |
386 | } | |
387 | ||
388 | static void superblock_free_security(struct super_block *sb) | |
389 | { | |
390 | struct superblock_security_struct *sbsec = sb->s_security; | |
1da177e4 LT |
391 | sb->s_security = NULL; |
392 | kfree(sbsec); | |
393 | } | |
394 | ||
bd323655 AV |
395 | struct selinux_mnt_opts { |
396 | const char *fscontext, *context, *rootcontext, *defcontext; | |
397 | }; | |
398 | ||
204cc0cc AV |
399 | static void selinux_free_mnt_opts(void *mnt_opts) |
400 | { | |
bd323655 AV |
401 | struct selinux_mnt_opts *opts = mnt_opts; |
402 | kfree(opts->fscontext); | |
403 | kfree(opts->context); | |
404 | kfree(opts->rootcontext); | |
405 | kfree(opts->defcontext); | |
204cc0cc AV |
406 | kfree(opts); |
407 | } | |
408 | ||
1da177e4 LT |
409 | static inline int inode_doinit(struct inode *inode) |
410 | { | |
411 | return inode_doinit_with_dentry(inode, NULL); | |
412 | } | |
413 | ||
414 | enum { | |
31e87930 | 415 | Opt_error = -1, |
442155c1 DH |
416 | Opt_context = 0, |
417 | Opt_defcontext = 1, | |
1da177e4 | 418 | Opt_fscontext = 2, |
442155c1 DH |
419 | Opt_rootcontext = 3, |
420 | Opt_seclabel = 4, | |
1da177e4 LT |
421 | }; |
422 | ||
da3d76ab | 423 | #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} |
169d68ef AV |
424 | static struct { |
425 | const char *name; | |
426 | int len; | |
427 | int opt; | |
428 | bool has_arg; | |
429 | } tokens[] = { | |
da3d76ab AV |
430 | A(context, true), |
431 | A(fscontext, true), | |
432 | A(defcontext, true), | |
433 | A(rootcontext, true), | |
434 | A(seclabel, false), | |
1da177e4 | 435 | }; |
169d68ef AV |
436 | #undef A |
437 | ||
438 | static int match_opt_prefix(char *s, int l, char **arg) | |
439 | { | |
440 | int i; | |
441 | ||
442 | for (i = 0; i < ARRAY_SIZE(tokens); i++) { | |
443 | size_t len = tokens[i].len; | |
444 | if (len > l || memcmp(s, tokens[i].name, len)) | |
445 | continue; | |
446 | if (tokens[i].has_arg) { | |
447 | if (len == l || s[len] != '=') | |
448 | continue; | |
449 | *arg = s + len + 1; | |
450 | } else if (len != l) | |
451 | continue; | |
452 | return tokens[i].opt; | |
453 | } | |
454 | return Opt_error; | |
455 | } | |
1da177e4 LT |
456 | |
457 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
458 | ||
c312feb2 EP |
459 | static int may_context_mount_sb_relabel(u32 sid, |
460 | struct superblock_security_struct *sbsec, | |
275bb41e | 461 | const struct cred *cred) |
c312feb2 | 462 | { |
0c6cfa62 | 463 | const struct task_security_struct *tsec = selinux_cred(cred); |
c312feb2 EP |
464 | int rc; |
465 | ||
6b6bc620 SS |
466 | rc = avc_has_perm(&selinux_state, |
467 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
468 | FILESYSTEM__RELABELFROM, NULL); |
469 | if (rc) | |
470 | return rc; | |
471 | ||
6b6bc620 SS |
472 | rc = avc_has_perm(&selinux_state, |
473 | tsec->sid, sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
474 | FILESYSTEM__RELABELTO, NULL); |
475 | return rc; | |
476 | } | |
477 | ||
0808925e EP |
478 | static int may_context_mount_inode_relabel(u32 sid, |
479 | struct superblock_security_struct *sbsec, | |
275bb41e | 480 | const struct cred *cred) |
0808925e | 481 | { |
0c6cfa62 | 482 | const struct task_security_struct *tsec = selinux_cred(cred); |
0808925e | 483 | int rc; |
6b6bc620 SS |
484 | rc = avc_has_perm(&selinux_state, |
485 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
486 | FILESYSTEM__RELABELFROM, NULL); |
487 | if (rc) | |
488 | return rc; | |
489 | ||
6b6bc620 SS |
490 | rc = avc_has_perm(&selinux_state, |
491 | sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
492 | FILESYSTEM__ASSOCIATE, NULL); |
493 | return rc; | |
494 | } | |
495 | ||
a83d6dda | 496 | static int selinux_is_genfs_special_handling(struct super_block *sb) |
b43e725d | 497 | { |
a83d6dda OM |
498 | /* Special handling. Genfs but also in-core setxattr handler */ |
499 | return !strcmp(sb->s_type->name, "sysfs") || | |
d5f3a5f6 MS |
500 | !strcmp(sb->s_type->name, "pstore") || |
501 | !strcmp(sb->s_type->name, "debugfs") || | |
a2c7c6fb | 502 | !strcmp(sb->s_type->name, "tracefs") || |
2651225b | 503 | !strcmp(sb->s_type->name, "rootfs") || |
aa8e712c | 504 | (selinux_policycap_cgroupseclabel() && |
2651225b SS |
505 | (!strcmp(sb->s_type->name, "cgroup") || |
506 | !strcmp(sb->s_type->name, "cgroup2"))); | |
b43e725d EP |
507 | } |
508 | ||
a83d6dda OM |
509 | static int selinux_is_sblabel_mnt(struct super_block *sb) |
510 | { | |
511 | struct superblock_security_struct *sbsec = sb->s_security; | |
512 | ||
513 | /* | |
514 | * IMPORTANT: Double-check logic in this function when adding a new | |
515 | * SECURITY_FS_USE_* definition! | |
516 | */ | |
517 | BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); | |
518 | ||
519 | switch (sbsec->behavior) { | |
520 | case SECURITY_FS_USE_XATTR: | |
521 | case SECURITY_FS_USE_TRANS: | |
522 | case SECURITY_FS_USE_TASK: | |
523 | case SECURITY_FS_USE_NATIVE: | |
524 | return 1; | |
525 | ||
526 | case SECURITY_FS_USE_GENFS: | |
527 | return selinux_is_genfs_special_handling(sb); | |
528 | ||
529 | /* Never allow relabeling on context mounts */ | |
530 | case SECURITY_FS_USE_MNTPOINT: | |
531 | case SECURITY_FS_USE_NONE: | |
532 | default: | |
533 | return 0; | |
534 | } | |
535 | } | |
536 | ||
c9180a57 | 537 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 538 | { |
1da177e4 | 539 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 | 540 | struct dentry *root = sb->s_root; |
c6f493d6 | 541 | struct inode *root_inode = d_backing_inode(root); |
c9180a57 | 542 | int rc = 0; |
1da177e4 | 543 | |
c9180a57 EP |
544 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
545 | /* Make sure that the xattr handler exists and that no | |
546 | error other than -ENODATA is returned by getxattr on | |
547 | the root directory. -ENODATA is ok, as this may be | |
548 | the first boot of the SELinux kernel before we have | |
549 | assigned xattr values to the filesystem. */ | |
5d6c3191 | 550 | if (!(root_inode->i_opflags & IOP_XATTR)) { |
c103a91e | 551 | pr_warn("SELinux: (dev %s, type %s) has no " |
29b1deb2 | 552 | "xattr support\n", sb->s_id, sb->s_type->name); |
c9180a57 EP |
553 | rc = -EOPNOTSUPP; |
554 | goto out; | |
555 | } | |
5d6c3191 AG |
556 | |
557 | rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); | |
c9180a57 EP |
558 | if (rc < 0 && rc != -ENODATA) { |
559 | if (rc == -EOPNOTSUPP) | |
c103a91e | 560 | pr_warn("SELinux: (dev %s, type " |
29b1deb2 LT |
561 | "%s) has no security xattr handler\n", |
562 | sb->s_id, sb->s_type->name); | |
c9180a57 | 563 | else |
c103a91e | 564 | pr_warn("SELinux: (dev %s, type " |
29b1deb2 LT |
565 | "%s) getxattr errno %d\n", sb->s_id, |
566 | sb->s_type->name, -rc); | |
c9180a57 EP |
567 | goto out; |
568 | } | |
569 | } | |
1da177e4 | 570 | |
eadcabc6 | 571 | sbsec->flags |= SE_SBINITIALIZED; |
0b4d3452 SM |
572 | |
573 | /* | |
574 | * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply | |
575 | * leave the flag untouched because sb_clone_mnt_opts might be handing | |
576 | * us a superblock that needs the flag to be cleared. | |
577 | */ | |
b43e725d | 578 | if (selinux_is_sblabel_mnt(sb)) |
12f348b9 | 579 | sbsec->flags |= SBLABEL_MNT; |
0b4d3452 SM |
580 | else |
581 | sbsec->flags &= ~SBLABEL_MNT; | |
ddd29ec6 | 582 | |
c9180a57 EP |
583 | /* Initialize the root inode. */ |
584 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 585 | |
c9180a57 EP |
586 | /* Initialize any other inodes associated with the superblock, e.g. |
587 | inodes created prior to initial policy load or inodes created | |
588 | during get_sb by a pseudo filesystem that directly | |
589 | populates itself. */ | |
590 | spin_lock(&sbsec->isec_lock); | |
8d64124a | 591 | while (!list_empty(&sbsec->isec_head)) { |
c9180a57 | 592 | struct inode_security_struct *isec = |
8d64124a | 593 | list_first_entry(&sbsec->isec_head, |
c9180a57 EP |
594 | struct inode_security_struct, list); |
595 | struct inode *inode = isec->inode; | |
923190d3 | 596 | list_del_init(&isec->list); |
c9180a57 EP |
597 | spin_unlock(&sbsec->isec_lock); |
598 | inode = igrab(inode); | |
599 | if (inode) { | |
600 | if (!IS_PRIVATE(inode)) | |
601 | inode_doinit(inode); | |
602 | iput(inode); | |
603 | } | |
604 | spin_lock(&sbsec->isec_lock); | |
c9180a57 EP |
605 | } |
606 | spin_unlock(&sbsec->isec_lock); | |
607 | out: | |
608 | return rc; | |
609 | } | |
1da177e4 | 610 | |
c9180a57 EP |
611 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
612 | u32 old_sid, u32 new_sid) | |
613 | { | |
0d90a7ec DQ |
614 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
615 | ||
c9180a57 | 616 | /* check if the old mount command had the same options */ |
0d90a7ec | 617 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
618 | if (!(sbsec->flags & flag) || |
619 | (old_sid != new_sid)) | |
620 | return 1; | |
621 | ||
622 | /* check if we were passed the same options twice, | |
623 | * aka someone passed context=a,context=b | |
624 | */ | |
0d90a7ec DQ |
625 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
626 | if (mnt_flags & flag) | |
c9180a57 EP |
627 | return 1; |
628 | return 0; | |
629 | } | |
e0007529 | 630 | |
bd323655 AV |
631 | static int parse_sid(struct super_block *sb, const char *s, u32 *sid) |
632 | { | |
633 | int rc = security_context_str_to_sid(&selinux_state, s, | |
634 | sid, GFP_KERNEL); | |
635 | if (rc) | |
636 | pr_warn("SELinux: security_context_str_to_sid" | |
637 | "(%s) failed for (dev %s, type %s) errno=%d\n", | |
638 | s, sb->s_id, sb->s_type->name, rc); | |
639 | return rc; | |
640 | } | |
641 | ||
c9180a57 EP |
642 | /* |
643 | * Allow filesystems with binary mount data to explicitly set mount point | |
644 | * labeling information. | |
645 | */ | |
e0007529 | 646 | static int selinux_set_mnt_opts(struct super_block *sb, |
204cc0cc | 647 | void *mnt_opts, |
649f6e77 DQ |
648 | unsigned long kern_flags, |
649 | unsigned long *set_kern_flags) | |
c9180a57 | 650 | { |
275bb41e | 651 | const struct cred *cred = current_cred(); |
c9180a57 | 652 | struct superblock_security_struct *sbsec = sb->s_security; |
83da53c5 | 653 | struct dentry *root = sbsec->sb->s_root; |
bd323655 | 654 | struct selinux_mnt_opts *opts = mnt_opts; |
2c97165b | 655 | struct inode_security_struct *root_isec; |
c9180a57 EP |
656 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
657 | u32 defcontext_sid = 0; | |
bd323655 | 658 | int rc = 0; |
c9180a57 EP |
659 | |
660 | mutex_lock(&sbsec->lock); | |
661 | ||
aa8e712c | 662 | if (!selinux_state.initialized) { |
bd323655 | 663 | if (!opts) { |
c9180a57 EP |
664 | /* Defer initialization until selinux_complete_init, |
665 | after the initial policy is loaded and the security | |
666 | server is ready to handle calls. */ | |
c9180a57 EP |
667 | goto out; |
668 | } | |
669 | rc = -EINVAL; | |
c103a91e | 670 | pr_warn("SELinux: Unable to set superblock options " |
744ba35e | 671 | "before the security server is initialized\n"); |
1da177e4 | 672 | goto out; |
c9180a57 | 673 | } |
649f6e77 DQ |
674 | if (kern_flags && !set_kern_flags) { |
675 | /* Specifying internal flags without providing a place to | |
676 | * place the results is not allowed */ | |
677 | rc = -EINVAL; | |
678 | goto out; | |
679 | } | |
1da177e4 | 680 | |
e0007529 EP |
681 | /* |
682 | * Binary mount data FS will come through this function twice. Once | |
683 | * from an explicit call and once from the generic calls from the vfs. | |
684 | * Since the generic VFS calls will not contain any security mount data | |
685 | * we need to skip the double mount verification. | |
686 | * | |
687 | * This does open a hole in which we will not notice if the first | |
688 | * mount using this sb set explict options and a second mount using | |
689 | * this sb does not set any security options. (The first options | |
690 | * will be used for both mounts) | |
691 | */ | |
0d90a7ec | 692 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
bd323655 | 693 | && !opts) |
f5269710 | 694 | goto out; |
e0007529 | 695 | |
2c97165b PM |
696 | root_isec = backing_inode_security_novalidate(root); |
697 | ||
c9180a57 EP |
698 | /* |
699 | * parse the mount options, check if they are valid sids. | |
700 | * also check if someone is trying to mount the same sb more | |
701 | * than once with different security options. | |
702 | */ | |
bd323655 AV |
703 | if (opts) { |
704 | if (opts->fscontext) { | |
705 | rc = parse_sid(sb, opts->fscontext, &fscontext_sid); | |
706 | if (rc) | |
707 | goto out; | |
c9180a57 EP |
708 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, |
709 | fscontext_sid)) | |
710 | goto out_double_mount; | |
c9180a57 | 711 | sbsec->flags |= FSCONTEXT_MNT; |
bd323655 AV |
712 | } |
713 | if (opts->context) { | |
714 | rc = parse_sid(sb, opts->context, &context_sid); | |
715 | if (rc) | |
716 | goto out; | |
c9180a57 EP |
717 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, |
718 | context_sid)) | |
719 | goto out_double_mount; | |
c9180a57 | 720 | sbsec->flags |= CONTEXT_MNT; |
bd323655 AV |
721 | } |
722 | if (opts->rootcontext) { | |
723 | rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid); | |
724 | if (rc) | |
725 | goto out; | |
c9180a57 EP |
726 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, |
727 | rootcontext_sid)) | |
728 | goto out_double_mount; | |
c9180a57 | 729 | sbsec->flags |= ROOTCONTEXT_MNT; |
bd323655 AV |
730 | } |
731 | if (opts->defcontext) { | |
732 | rc = parse_sid(sb, opts->defcontext, &defcontext_sid); | |
733 | if (rc) | |
734 | goto out; | |
c9180a57 EP |
735 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, |
736 | defcontext_sid)) | |
737 | goto out_double_mount; | |
c9180a57 | 738 | sbsec->flags |= DEFCONTEXT_MNT; |
1da177e4 | 739 | } |
c9180a57 EP |
740 | } |
741 | ||
0d90a7ec | 742 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 743 | /* previously mounted with options, but not on this attempt? */ |
bd323655 | 744 | if ((sbsec->flags & SE_MNTMASK) && !opts) |
c9180a57 EP |
745 | goto out_double_mount; |
746 | rc = 0; | |
747 | goto out; | |
748 | } | |
749 | ||
089be43e | 750 | if (strcmp(sb->s_type->name, "proc") == 0) |
134509d5 SS |
751 | sbsec->flags |= SE_SBPROC | SE_SBGENFS; |
752 | ||
8e014720 | 753 | if (!strcmp(sb->s_type->name, "debugfs") || |
6a391183 | 754 | !strcmp(sb->s_type->name, "tracefs") || |
b754026b OM |
755 | !strcmp(sb->s_type->name, "pstore")) |
756 | sbsec->flags |= SE_SBGENFS; | |
757 | ||
758 | if (!strcmp(sb->s_type->name, "sysfs") || | |
901ef845 AM |
759 | !strcmp(sb->s_type->name, "cgroup") || |
760 | !strcmp(sb->s_type->name, "cgroup2")) | |
b754026b | 761 | sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; |
c9180a57 | 762 | |
eb9ae686 DQ |
763 | if (!sbsec->behavior) { |
764 | /* | |
765 | * Determine the labeling behavior to use for this | |
766 | * filesystem type. | |
767 | */ | |
aa8e712c | 768 | rc = security_fs_use(&selinux_state, sb); |
eb9ae686 | 769 | if (rc) { |
c103a91e | 770 | pr_warn("%s: security_fs_use(%s) returned %d\n", |
eb9ae686 DQ |
771 | __func__, sb->s_type->name, rc); |
772 | goto out; | |
773 | } | |
c9180a57 | 774 | } |
aad82892 SF |
775 | |
776 | /* | |
01593d32 SS |
777 | * If this is a user namespace mount and the filesystem type is not |
778 | * explicitly whitelisted, then no contexts are allowed on the command | |
779 | * line and security labels must be ignored. | |
aad82892 | 780 | */ |
01593d32 SS |
781 | if (sb->s_user_ns != &init_user_ns && |
782 | strcmp(sb->s_type->name, "tmpfs") && | |
783 | strcmp(sb->s_type->name, "ramfs") && | |
784 | strcmp(sb->s_type->name, "devpts")) { | |
aad82892 SF |
785 | if (context_sid || fscontext_sid || rootcontext_sid || |
786 | defcontext_sid) { | |
787 | rc = -EACCES; | |
788 | goto out; | |
789 | } | |
790 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { | |
791 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; | |
aa8e712c SS |
792 | rc = security_transition_sid(&selinux_state, |
793 | current_sid(), | |
794 | current_sid(), | |
aad82892 SF |
795 | SECCLASS_FILE, NULL, |
796 | &sbsec->mntpoint_sid); | |
797 | if (rc) | |
798 | goto out; | |
799 | } | |
800 | goto out_set_opts; | |
801 | } | |
802 | ||
c9180a57 EP |
803 | /* sets the context of the superblock for the fs being mounted. */ |
804 | if (fscontext_sid) { | |
275bb41e | 805 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
1da177e4 | 806 | if (rc) |
c9180a57 | 807 | goto out; |
1da177e4 | 808 | |
c9180a57 | 809 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
810 | } |
811 | ||
812 | /* | |
813 | * Switch to using mount point labeling behavior. | |
814 | * sets the label used on all file below the mountpoint, and will set | |
815 | * the superblock context if not already set. | |
816 | */ | |
eb9ae686 DQ |
817 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { |
818 | sbsec->behavior = SECURITY_FS_USE_NATIVE; | |
819 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
820 | } | |
821 | ||
c9180a57 EP |
822 | if (context_sid) { |
823 | if (!fscontext_sid) { | |
275bb41e DH |
824 | rc = may_context_mount_sb_relabel(context_sid, sbsec, |
825 | cred); | |
b04ea3ce | 826 | if (rc) |
c9180a57 EP |
827 | goto out; |
828 | sbsec->sid = context_sid; | |
b04ea3ce | 829 | } else { |
275bb41e DH |
830 | rc = may_context_mount_inode_relabel(context_sid, sbsec, |
831 | cred); | |
b04ea3ce | 832 | if (rc) |
c9180a57 | 833 | goto out; |
b04ea3ce | 834 | } |
c9180a57 EP |
835 | if (!rootcontext_sid) |
836 | rootcontext_sid = context_sid; | |
1da177e4 | 837 | |
c9180a57 | 838 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 839 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
840 | } |
841 | ||
c9180a57 | 842 | if (rootcontext_sid) { |
275bb41e DH |
843 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
844 | cred); | |
0808925e | 845 | if (rc) |
c9180a57 | 846 | goto out; |
0808925e | 847 | |
c9180a57 | 848 | root_isec->sid = rootcontext_sid; |
6f3be9f5 | 849 | root_isec->initialized = LABEL_INITIALIZED; |
0808925e EP |
850 | } |
851 | ||
c9180a57 | 852 | if (defcontext_sid) { |
eb9ae686 DQ |
853 | if (sbsec->behavior != SECURITY_FS_USE_XATTR && |
854 | sbsec->behavior != SECURITY_FS_USE_NATIVE) { | |
c9180a57 | 855 | rc = -EINVAL; |
c103a91e | 856 | pr_warn("SELinux: defcontext option is " |
c9180a57 EP |
857 | "invalid for this filesystem type\n"); |
858 | goto out; | |
1da177e4 LT |
859 | } |
860 | ||
c9180a57 EP |
861 | if (defcontext_sid != sbsec->def_sid) { |
862 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
275bb41e | 863 | sbsec, cred); |
c9180a57 EP |
864 | if (rc) |
865 | goto out; | |
866 | } | |
1da177e4 | 867 | |
c9180a57 | 868 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
869 | } |
870 | ||
aad82892 | 871 | out_set_opts: |
c9180a57 | 872 | rc = sb_finish_set_opts(sb); |
1da177e4 | 873 | out: |
c9180a57 | 874 | mutex_unlock(&sbsec->lock); |
1da177e4 | 875 | return rc; |
c9180a57 EP |
876 | out_double_mount: |
877 | rc = -EINVAL; | |
c103a91e | 878 | pr_warn("SELinux: mount invalid. Same superblock, different " |
bd323655 AV |
879 | "security settings for (dev %s, type %s)\n", sb->s_id, |
880 | sb->s_type->name); | |
c9180a57 | 881 | goto out; |
1da177e4 LT |
882 | } |
883 | ||
094f7b69 JL |
884 | static int selinux_cmp_sb_context(const struct super_block *oldsb, |
885 | const struct super_block *newsb) | |
886 | { | |
887 | struct superblock_security_struct *old = oldsb->s_security; | |
888 | struct superblock_security_struct *new = newsb->s_security; | |
889 | char oldflags = old->flags & SE_MNTMASK; | |
890 | char newflags = new->flags & SE_MNTMASK; | |
891 | ||
892 | if (oldflags != newflags) | |
893 | goto mismatch; | |
894 | if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) | |
895 | goto mismatch; | |
896 | if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) | |
897 | goto mismatch; | |
898 | if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) | |
899 | goto mismatch; | |
900 | if (oldflags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
901 | struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); |
902 | struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); | |
094f7b69 JL |
903 | if (oldroot->sid != newroot->sid) |
904 | goto mismatch; | |
905 | } | |
906 | return 0; | |
907 | mismatch: | |
c103a91e | 908 | pr_warn("SELinux: mount invalid. Same superblock, " |
094f7b69 JL |
909 | "different security settings for (dev %s, " |
910 | "type %s)\n", newsb->s_id, newsb->s_type->name); | |
911 | return -EBUSY; | |
912 | } | |
913 | ||
914 | static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, | |
0b4d3452 SM |
915 | struct super_block *newsb, |
916 | unsigned long kern_flags, | |
917 | unsigned long *set_kern_flags) | |
1da177e4 | 918 | { |
0b4d3452 | 919 | int rc = 0; |
c9180a57 EP |
920 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
921 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 922 | |
c9180a57 EP |
923 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
924 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
925 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 926 | |
0f5e6420 EP |
927 | /* |
928 | * if the parent was able to be mounted it clearly had no special lsm | |
e8c26255 | 929 | * mount options. thus we can safely deal with this superblock later |
0f5e6420 | 930 | */ |
aa8e712c | 931 | if (!selinux_state.initialized) |
094f7b69 | 932 | return 0; |
c9180a57 | 933 | |
0b4d3452 SM |
934 | /* |
935 | * Specifying internal flags without providing a place to | |
936 | * place the results is not allowed. | |
937 | */ | |
938 | if (kern_flags && !set_kern_flags) | |
939 | return -EINVAL; | |
940 | ||
c9180a57 | 941 | /* how can we clone if the old one wasn't set up?? */ |
0d90a7ec | 942 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
c9180a57 | 943 | |
094f7b69 | 944 | /* if fs is reusing a sb, make sure that the contexts match */ |
3815a245 BF |
945 | if (newsbsec->flags & SE_SBINITIALIZED) { |
946 | if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) | |
947 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
094f7b69 | 948 | return selinux_cmp_sb_context(oldsb, newsb); |
3815a245 | 949 | } |
5a552617 | 950 | |
c9180a57 EP |
951 | mutex_lock(&newsbsec->lock); |
952 | ||
953 | newsbsec->flags = oldsbsec->flags; | |
954 | ||
955 | newsbsec->sid = oldsbsec->sid; | |
956 | newsbsec->def_sid = oldsbsec->def_sid; | |
957 | newsbsec->behavior = oldsbsec->behavior; | |
958 | ||
0b4d3452 SM |
959 | if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && |
960 | !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { | |
aa8e712c | 961 | rc = security_fs_use(&selinux_state, newsb); |
0b4d3452 SM |
962 | if (rc) |
963 | goto out; | |
964 | } | |
965 | ||
966 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { | |
967 | newsbsec->behavior = SECURITY_FS_USE_NATIVE; | |
968 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
969 | } | |
970 | ||
c9180a57 EP |
971 | if (set_context) { |
972 | u32 sid = oldsbsec->mntpoint_sid; | |
973 | ||
974 | if (!set_fscontext) | |
975 | newsbsec->sid = sid; | |
976 | if (!set_rootcontext) { | |
83da53c5 | 977 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); |
c9180a57 EP |
978 | newisec->sid = sid; |
979 | } | |
980 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 981 | } |
c9180a57 | 982 | if (set_rootcontext) { |
83da53c5 AG |
983 | const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); |
984 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); | |
1da177e4 | 985 | |
c9180a57 | 986 | newisec->sid = oldisec->sid; |
1da177e4 LT |
987 | } |
988 | ||
c9180a57 | 989 | sb_finish_set_opts(newsb); |
0b4d3452 | 990 | out: |
c9180a57 | 991 | mutex_unlock(&newsbsec->lock); |
0b4d3452 | 992 | return rc; |
c9180a57 EP |
993 | } |
994 | ||
ba641862 | 995 | static int selinux_add_opt(int token, const char *s, void **mnt_opts) |
c9180a57 | 996 | { |
ba641862 | 997 | struct selinux_mnt_opts *opts = *mnt_opts; |
1da177e4 | 998 | |
da3d76ab | 999 | if (token == Opt_seclabel) /* eaten and completely ignored */ |
169d68ef | 1000 | return 0; |
e0007529 | 1001 | |
ba641862 AV |
1002 | if (!opts) { |
1003 | opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); | |
1004 | if (!opts) | |
1005 | return -ENOMEM; | |
1006 | *mnt_opts = opts; | |
c9180a57 | 1007 | } |
ba641862 AV |
1008 | if (!s) |
1009 | return -ENOMEM; | |
1010 | switch (token) { | |
1011 | case Opt_context: | |
1012 | if (opts->context || opts->defcontext) | |
1013 | goto Einval; | |
1014 | opts->context = s; | |
1015 | break; | |
1016 | case Opt_fscontext: | |
1017 | if (opts->fscontext) | |
1018 | goto Einval; | |
1019 | opts->fscontext = s; | |
1020 | break; | |
1021 | case Opt_rootcontext: | |
1022 | if (opts->rootcontext) | |
1023 | goto Einval; | |
1024 | opts->rootcontext = s; | |
1025 | break; | |
1026 | case Opt_defcontext: | |
1027 | if (opts->context || opts->defcontext) | |
1028 | goto Einval; | |
1029 | opts->defcontext = s; | |
1030 | break; | |
c9180a57 | 1031 | } |
e0007529 | 1032 | return 0; |
ba641862 AV |
1033 | Einval: |
1034 | pr_warn(SEL_MOUNT_FAIL_MSG); | |
ba641862 | 1035 | return -EINVAL; |
1da177e4 | 1036 | } |
e0007529 | 1037 | |
757cbe59 AV |
1038 | static int selinux_add_mnt_opt(const char *option, const char *val, int len, |
1039 | void **mnt_opts) | |
c9180a57 | 1040 | { |
757cbe59 AV |
1041 | int token = Opt_error; |
1042 | int rc, i; | |
e0007529 | 1043 | |
757cbe59 AV |
1044 | for (i = 0; i < ARRAY_SIZE(tokens); i++) { |
1045 | if (strcmp(option, tokens[i].name) == 0) { | |
1046 | token = tokens[i].opt; | |
1047 | break; | |
169d68ef | 1048 | } |
757cbe59 | 1049 | } |
e0007529 | 1050 | |
757cbe59 AV |
1051 | if (token == Opt_error) |
1052 | return -EINVAL; | |
e0007529 | 1053 | |
e2e0e097 | 1054 | if (token != Opt_seclabel) { |
757cbe59 | 1055 | val = kmemdup_nul(val, len, GFP_KERNEL); |
e2e0e097 GZ |
1056 | if (!val) { |
1057 | rc = -ENOMEM; | |
1058 | goto free_opt; | |
1059 | } | |
1060 | } | |
757cbe59 AV |
1061 | rc = selinux_add_opt(token, val, mnt_opts); |
1062 | if (unlikely(rc)) { | |
1063 | kfree(val); | |
e2e0e097 GZ |
1064 | goto free_opt; |
1065 | } | |
1066 | return rc; | |
1067 | ||
1068 | free_opt: | |
1069 | if (*mnt_opts) { | |
1070 | selinux_free_mnt_opts(*mnt_opts); | |
1071 | *mnt_opts = NULL; | |
1da177e4 | 1072 | } |
e0007529 EP |
1073 | return rc; |
1074 | } | |
1da177e4 | 1075 | |
e3489f89 | 1076 | static int show_sid(struct seq_file *m, u32 sid) |
2069f457 | 1077 | { |
e3489f89 AV |
1078 | char *context = NULL; |
1079 | u32 len; | |
1080 | int rc; | |
11689d47 | 1081 | |
e3489f89 AV |
1082 | rc = security_sid_to_context(&selinux_state, sid, |
1083 | &context, &len); | |
1084 | if (!rc) { | |
1085 | bool has_comma = context && strchr(context, ','); | |
2069f457 | 1086 | |
442155c1 | 1087 | seq_putc(m, '='); |
2069f457 EP |
1088 | if (has_comma) |
1089 | seq_putc(m, '\"'); | |
e3489f89 | 1090 | seq_escape(m, context, "\"\n\\"); |
2069f457 EP |
1091 | if (has_comma) |
1092 | seq_putc(m, '\"'); | |
1093 | } | |
e3489f89 AV |
1094 | kfree(context); |
1095 | return rc; | |
2069f457 EP |
1096 | } |
1097 | ||
1098 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1099 | { | |
e3489f89 | 1100 | struct superblock_security_struct *sbsec = sb->s_security; |
2069f457 EP |
1101 | int rc; |
1102 | ||
e3489f89 AV |
1103 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
1104 | return 0; | |
2069f457 | 1105 | |
e3489f89 AV |
1106 | if (!selinux_state.initialized) |
1107 | return 0; | |
2069f457 | 1108 | |
e3489f89 AV |
1109 | if (sbsec->flags & FSCONTEXT_MNT) { |
1110 | seq_putc(m, ','); | |
1111 | seq_puts(m, FSCONTEXT_STR); | |
1112 | rc = show_sid(m, sbsec->sid); | |
1113 | if (rc) | |
1114 | return rc; | |
1115 | } | |
1116 | if (sbsec->flags & CONTEXT_MNT) { | |
1117 | seq_putc(m, ','); | |
1118 | seq_puts(m, CONTEXT_STR); | |
1119 | rc = show_sid(m, sbsec->mntpoint_sid); | |
1120 | if (rc) | |
1121 | return rc; | |
1122 | } | |
1123 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
1124 | seq_putc(m, ','); | |
1125 | seq_puts(m, DEFCONTEXT_STR); | |
1126 | rc = show_sid(m, sbsec->def_sid); | |
1127 | if (rc) | |
1128 | return rc; | |
1129 | } | |
1130 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
1131 | struct dentry *root = sbsec->sb->s_root; | |
1132 | struct inode_security_struct *isec = backing_inode_security(root); | |
1133 | seq_putc(m, ','); | |
1134 | seq_puts(m, ROOTCONTEXT_STR); | |
1135 | rc = show_sid(m, isec->sid); | |
1136 | if (rc) | |
1137 | return rc; | |
1138 | } | |
1139 | if (sbsec->flags & SBLABEL_MNT) { | |
1140 | seq_putc(m, ','); | |
442155c1 | 1141 | seq_puts(m, SECLABEL_STR); |
e3489f89 AV |
1142 | } |
1143 | return 0; | |
2069f457 EP |
1144 | } |
1145 | ||
1da177e4 LT |
1146 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1147 | { | |
1148 | switch (mode & S_IFMT) { | |
1149 | case S_IFSOCK: | |
1150 | return SECCLASS_SOCK_FILE; | |
1151 | case S_IFLNK: | |
1152 | return SECCLASS_LNK_FILE; | |
1153 | case S_IFREG: | |
1154 | return SECCLASS_FILE; | |
1155 | case S_IFBLK: | |
1156 | return SECCLASS_BLK_FILE; | |
1157 | case S_IFDIR: | |
1158 | return SECCLASS_DIR; | |
1159 | case S_IFCHR: | |
1160 | return SECCLASS_CHR_FILE; | |
1161 | case S_IFIFO: | |
1162 | return SECCLASS_FIFO_FILE; | |
1163 | ||
1164 | } | |
1165 | ||
1166 | return SECCLASS_FILE; | |
1167 | } | |
1168 | ||
13402580 JM |
1169 | static inline int default_protocol_stream(int protocol) |
1170 | { | |
1171 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1172 | } | |
1173 | ||
1174 | static inline int default_protocol_dgram(int protocol) | |
1175 | { | |
1176 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1177 | } | |
1178 | ||
1da177e4 LT |
1179 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1180 | { | |
aa8e712c | 1181 | int extsockclass = selinux_policycap_extsockclass(); |
da69a530 | 1182 | |
1da177e4 LT |
1183 | switch (family) { |
1184 | case PF_UNIX: | |
1185 | switch (type) { | |
1186 | case SOCK_STREAM: | |
1187 | case SOCK_SEQPACKET: | |
1188 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1189 | case SOCK_DGRAM: | |
2a764b52 | 1190 | case SOCK_RAW: |
1da177e4 LT |
1191 | return SECCLASS_UNIX_DGRAM_SOCKET; |
1192 | } | |
1193 | break; | |
1194 | case PF_INET: | |
1195 | case PF_INET6: | |
1196 | switch (type) { | |
1197 | case SOCK_STREAM: | |
da69a530 | 1198 | case SOCK_SEQPACKET: |
13402580 JM |
1199 | if (default_protocol_stream(protocol)) |
1200 | return SECCLASS_TCP_SOCKET; | |
da69a530 SS |
1201 | else if (extsockclass && protocol == IPPROTO_SCTP) |
1202 | return SECCLASS_SCTP_SOCKET; | |
13402580 JM |
1203 | else |
1204 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1205 | case SOCK_DGRAM: |
13402580 JM |
1206 | if (default_protocol_dgram(protocol)) |
1207 | return SECCLASS_UDP_SOCKET; | |
ef37979a SS |
1208 | else if (extsockclass && (protocol == IPPROTO_ICMP || |
1209 | protocol == IPPROTO_ICMPV6)) | |
da69a530 | 1210 | return SECCLASS_ICMP_SOCKET; |
13402580 JM |
1211 | else |
1212 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1213 | case SOCK_DCCP: |
1214 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1215 | default: |
1da177e4 LT |
1216 | return SECCLASS_RAWIP_SOCKET; |
1217 | } | |
1218 | break; | |
1219 | case PF_NETLINK: | |
1220 | switch (protocol) { | |
1221 | case NETLINK_ROUTE: | |
1222 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
7f1fb60c | 1223 | case NETLINK_SOCK_DIAG: |
1da177e4 LT |
1224 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1225 | case NETLINK_NFLOG: | |
1226 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1227 | case NETLINK_XFRM: | |
1228 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1229 | case NETLINK_SELINUX: | |
1230 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
6c6d2e9b SS |
1231 | case NETLINK_ISCSI: |
1232 | return SECCLASS_NETLINK_ISCSI_SOCKET; | |
1da177e4 LT |
1233 | case NETLINK_AUDIT: |
1234 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
6c6d2e9b SS |
1235 | case NETLINK_FIB_LOOKUP: |
1236 | return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; | |
1237 | case NETLINK_CONNECTOR: | |
1238 | return SECCLASS_NETLINK_CONNECTOR_SOCKET; | |
1239 | case NETLINK_NETFILTER: | |
1240 | return SECCLASS_NETLINK_NETFILTER_SOCKET; | |
1da177e4 LT |
1241 | case NETLINK_DNRTMSG: |
1242 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1243 | case NETLINK_KOBJECT_UEVENT: |
1244 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
6c6d2e9b SS |
1245 | case NETLINK_GENERIC: |
1246 | return SECCLASS_NETLINK_GENERIC_SOCKET; | |
1247 | case NETLINK_SCSITRANSPORT: | |
1248 | return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; | |
1249 | case NETLINK_RDMA: | |
1250 | return SECCLASS_NETLINK_RDMA_SOCKET; | |
1251 | case NETLINK_CRYPTO: | |
1252 | return SECCLASS_NETLINK_CRYPTO_SOCKET; | |
1da177e4 LT |
1253 | default: |
1254 | return SECCLASS_NETLINK_SOCKET; | |
1255 | } | |
1256 | case PF_PACKET: | |
1257 | return SECCLASS_PACKET_SOCKET; | |
1258 | case PF_KEY: | |
1259 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1260 | case PF_APPLETALK: |
1261 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1262 | } |
1263 | ||
da69a530 SS |
1264 | if (extsockclass) { |
1265 | switch (family) { | |
1266 | case PF_AX25: | |
1267 | return SECCLASS_AX25_SOCKET; | |
1268 | case PF_IPX: | |
1269 | return SECCLASS_IPX_SOCKET; | |
1270 | case PF_NETROM: | |
1271 | return SECCLASS_NETROM_SOCKET; | |
da69a530 SS |
1272 | case PF_ATMPVC: |
1273 | return SECCLASS_ATMPVC_SOCKET; | |
1274 | case PF_X25: | |
1275 | return SECCLASS_X25_SOCKET; | |
1276 | case PF_ROSE: | |
1277 | return SECCLASS_ROSE_SOCKET; | |
1278 | case PF_DECnet: | |
1279 | return SECCLASS_DECNET_SOCKET; | |
1280 | case PF_ATMSVC: | |
1281 | return SECCLASS_ATMSVC_SOCKET; | |
1282 | case PF_RDS: | |
1283 | return SECCLASS_RDS_SOCKET; | |
1284 | case PF_IRDA: | |
1285 | return SECCLASS_IRDA_SOCKET; | |
1286 | case PF_PPPOX: | |
1287 | return SECCLASS_PPPOX_SOCKET; | |
1288 | case PF_LLC: | |
1289 | return SECCLASS_LLC_SOCKET; | |
da69a530 SS |
1290 | case PF_CAN: |
1291 | return SECCLASS_CAN_SOCKET; | |
1292 | case PF_TIPC: | |
1293 | return SECCLASS_TIPC_SOCKET; | |
1294 | case PF_BLUETOOTH: | |
1295 | return SECCLASS_BLUETOOTH_SOCKET; | |
1296 | case PF_IUCV: | |
1297 | return SECCLASS_IUCV_SOCKET; | |
1298 | case PF_RXRPC: | |
1299 | return SECCLASS_RXRPC_SOCKET; | |
1300 | case PF_ISDN: | |
1301 | return SECCLASS_ISDN_SOCKET; | |
1302 | case PF_PHONET: | |
1303 | return SECCLASS_PHONET_SOCKET; | |
1304 | case PF_IEEE802154: | |
1305 | return SECCLASS_IEEE802154_SOCKET; | |
1306 | case PF_CAIF: | |
1307 | return SECCLASS_CAIF_SOCKET; | |
1308 | case PF_ALG: | |
1309 | return SECCLASS_ALG_SOCKET; | |
1310 | case PF_NFC: | |
1311 | return SECCLASS_NFC_SOCKET; | |
1312 | case PF_VSOCK: | |
1313 | return SECCLASS_VSOCK_SOCKET; | |
1314 | case PF_KCM: | |
1315 | return SECCLASS_KCM_SOCKET; | |
1316 | case PF_QIPCRTR: | |
1317 | return SECCLASS_QIPCRTR_SOCKET; | |
3051bf36 LT |
1318 | case PF_SMC: |
1319 | return SECCLASS_SMC_SOCKET; | |
68e8b849 BT |
1320 | case PF_XDP: |
1321 | return SECCLASS_XDP_SOCKET; | |
1322 | #if PF_MAX > 45 | |
da69a530 SS |
1323 | #error New address family defined, please update this function. |
1324 | #endif | |
1325 | } | |
1326 | } | |
1327 | ||
1da177e4 LT |
1328 | return SECCLASS_SOCKET; |
1329 | } | |
1330 | ||
134509d5 SS |
1331 | static int selinux_genfs_get_sid(struct dentry *dentry, |
1332 | u16 tclass, | |
1333 | u16 flags, | |
1334 | u32 *sid) | |
1da177e4 | 1335 | { |
8e6c9693 | 1336 | int rc; |
fc64005c | 1337 | struct super_block *sb = dentry->d_sb; |
8e6c9693 | 1338 | char *buffer, *path; |
1da177e4 | 1339 | |
828dfe1d | 1340 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1341 | if (!buffer) |
1342 | return -ENOMEM; | |
1343 | ||
8e6c9693 LAG |
1344 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1345 | if (IS_ERR(path)) | |
1346 | rc = PTR_ERR(path); | |
1347 | else { | |
134509d5 SS |
1348 | if (flags & SE_SBPROC) { |
1349 | /* each process gets a /proc/PID/ entry. Strip off the | |
1350 | * PID part to get a valid selinux labeling. | |
1351 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1352 | while (path[1] >= '0' && path[1] <= '9') { | |
1353 | path[1] = '/'; | |
1354 | path++; | |
1355 | } | |
8e6c9693 | 1356 | } |
aa8e712c SS |
1357 | rc = security_genfs_sid(&selinux_state, sb->s_type->name, |
1358 | path, tclass, sid); | |
7bb185ed SS |
1359 | if (rc == -ENOENT) { |
1360 | /* No match in policy, mark as unlabeled. */ | |
1361 | *sid = SECINITSID_UNLABELED; | |
1362 | rc = 0; | |
1363 | } | |
1da177e4 | 1364 | } |
1da177e4 LT |
1365 | free_page((unsigned long)buffer); |
1366 | return rc; | |
1367 | } | |
1da177e4 | 1368 | |
b754026b OM |
1369 | static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, |
1370 | u32 def_sid, u32 *sid) | |
1371 | { | |
1372 | #define INITCONTEXTLEN 255 | |
1373 | char *context; | |
1374 | unsigned int len; | |
1375 | int rc; | |
1376 | ||
1377 | len = INITCONTEXTLEN; | |
1378 | context = kmalloc(len + 1, GFP_NOFS); | |
1379 | if (!context) | |
1380 | return -ENOMEM; | |
1381 | ||
1382 | context[len] = '\0'; | |
1383 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); | |
1384 | if (rc == -ERANGE) { | |
1385 | kfree(context); | |
1386 | ||
1387 | /* Need a larger buffer. Query for the right size. */ | |
1388 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); | |
1389 | if (rc < 0) | |
1390 | return rc; | |
1391 | ||
1392 | len = rc; | |
1393 | context = kmalloc(len + 1, GFP_NOFS); | |
1394 | if (!context) | |
1395 | return -ENOMEM; | |
1396 | ||
1397 | context[len] = '\0'; | |
1398 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, | |
1399 | context, len); | |
1400 | } | |
1401 | if (rc < 0) { | |
1402 | kfree(context); | |
1403 | if (rc != -ENODATA) { | |
1404 | pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", | |
1405 | __func__, -rc, inode->i_sb->s_id, inode->i_ino); | |
1406 | return rc; | |
1407 | } | |
1408 | *sid = def_sid; | |
1409 | return 0; | |
1410 | } | |
1411 | ||
1412 | rc = security_context_to_sid_default(&selinux_state, context, rc, sid, | |
1413 | def_sid, GFP_NOFS); | |
1414 | if (rc) { | |
1415 | char *dev = inode->i_sb->s_id; | |
1416 | unsigned long ino = inode->i_ino; | |
1417 | ||
1418 | if (rc == -EINVAL) { | |
1419 | pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s. This indicates you may need to relabel the inode or the filesystem in question.\n", | |
1420 | ino, dev, context); | |
1421 | } else { | |
1422 | pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", | |
1423 | __func__, context, -rc, dev, ino); | |
1424 | } | |
1425 | } | |
1426 | kfree(context); | |
1427 | return 0; | |
1428 | } | |
1429 | ||
1da177e4 LT |
1430 | /* The inode's security attributes must be initialized before first use. */ |
1431 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1432 | { | |
1433 | struct superblock_security_struct *sbsec = NULL; | |
80788c22 | 1434 | struct inode_security_struct *isec = selinux_inode(inode); |
9287aed2 AG |
1435 | u32 task_sid, sid = 0; |
1436 | u16 sclass; | |
1da177e4 | 1437 | struct dentry *dentry; |
1da177e4 | 1438 | int rc = 0; |
1da177e4 | 1439 | |
6f3be9f5 | 1440 | if (isec->initialized == LABEL_INITIALIZED) |
13457d07 | 1441 | return 0; |
1da177e4 | 1442 | |
9287aed2 | 1443 | spin_lock(&isec->lock); |
6f3be9f5 | 1444 | if (isec->initialized == LABEL_INITIALIZED) |
23970741 | 1445 | goto out_unlock; |
1da177e4 | 1446 | |
13457d07 AG |
1447 | if (isec->sclass == SECCLASS_FILE) |
1448 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1449 | ||
1da177e4 | 1450 | sbsec = inode->i_sb->s_security; |
0d90a7ec | 1451 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1452 | /* Defer initialization until selinux_complete_init, |
1453 | after the initial policy is loaded and the security | |
1454 | server is ready to handle calls. */ | |
1455 | spin_lock(&sbsec->isec_lock); | |
1456 | if (list_empty(&isec->list)) | |
1457 | list_add(&isec->list, &sbsec->isec_head); | |
1458 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1459 | goto out_unlock; |
1da177e4 LT |
1460 | } |
1461 | ||
9287aed2 AG |
1462 | sclass = isec->sclass; |
1463 | task_sid = isec->task_sid; | |
1464 | sid = isec->sid; | |
1465 | isec->initialized = LABEL_PENDING; | |
1466 | spin_unlock(&isec->lock); | |
1467 | ||
1da177e4 | 1468 | switch (sbsec->behavior) { |
eb9ae686 DQ |
1469 | case SECURITY_FS_USE_NATIVE: |
1470 | break; | |
1da177e4 | 1471 | case SECURITY_FS_USE_XATTR: |
5d6c3191 | 1472 | if (!(inode->i_opflags & IOP_XATTR)) { |
9287aed2 | 1473 | sid = sbsec->def_sid; |
1da177e4 LT |
1474 | break; |
1475 | } | |
1da177e4 LT |
1476 | /* Need a dentry, since the xattr API requires one. |
1477 | Life would be simpler if we could just pass the inode. */ | |
1478 | if (opt_dentry) { | |
1479 | /* Called from d_instantiate or d_splice_alias. */ | |
1480 | dentry = dget(opt_dentry); | |
1481 | } else { | |
b127125d AV |
1482 | /* |
1483 | * Called from selinux_complete_init, try to find a dentry. | |
1484 | * Some filesystems really want a connected one, so try | |
1485 | * that first. We could split SECURITY_FS_USE_XATTR in | |
1486 | * two, depending upon that... | |
1487 | */ | |
1da177e4 | 1488 | dentry = d_find_alias(inode); |
b127125d AV |
1489 | if (!dentry) |
1490 | dentry = d_find_any_alias(inode); | |
1da177e4 LT |
1491 | } |
1492 | if (!dentry) { | |
df7f54c0 EP |
1493 | /* |
1494 | * this is can be hit on boot when a file is accessed | |
1495 | * before the policy is loaded. When we load policy we | |
1496 | * may find inodes that have no dentry on the | |
1497 | * sbsec->isec_head list. No reason to complain as these | |
1498 | * will get fixed up the next time we go through | |
1499 | * inode_doinit with a dentry, before these inodes could | |
1500 | * be used again by userspace. | |
1501 | */ | |
9287aed2 | 1502 | goto out; |
1da177e4 LT |
1503 | } |
1504 | ||
b754026b OM |
1505 | rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, |
1506 | &sid); | |
1da177e4 | 1507 | dput(dentry); |
b754026b OM |
1508 | if (rc) |
1509 | goto out; | |
1da177e4 LT |
1510 | break; |
1511 | case SECURITY_FS_USE_TASK: | |
9287aed2 | 1512 | sid = task_sid; |
1da177e4 LT |
1513 | break; |
1514 | case SECURITY_FS_USE_TRANS: | |
1515 | /* Default to the fs SID. */ | |
9287aed2 | 1516 | sid = sbsec->sid; |
1da177e4 LT |
1517 | |
1518 | /* Try to obtain a transition SID. */ | |
aa8e712c SS |
1519 | rc = security_transition_sid(&selinux_state, task_sid, sid, |
1520 | sclass, NULL, &sid); | |
1da177e4 | 1521 | if (rc) |
9287aed2 | 1522 | goto out; |
1da177e4 | 1523 | break; |
c312feb2 | 1524 | case SECURITY_FS_USE_MNTPOINT: |
9287aed2 | 1525 | sid = sbsec->mntpoint_sid; |
c312feb2 | 1526 | break; |
1da177e4 | 1527 | default: |
c312feb2 | 1528 | /* Default to the fs superblock SID. */ |
9287aed2 | 1529 | sid = sbsec->sid; |
1da177e4 | 1530 | |
134509d5 | 1531 | if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) { |
f64410ec PM |
1532 | /* We must have a dentry to determine the label on |
1533 | * procfs inodes */ | |
b127125d | 1534 | if (opt_dentry) { |
f64410ec PM |
1535 | /* Called from d_instantiate or |
1536 | * d_splice_alias. */ | |
1537 | dentry = dget(opt_dentry); | |
b127125d | 1538 | } else { |
f64410ec | 1539 | /* Called from selinux_complete_init, try to |
b127125d AV |
1540 | * find a dentry. Some filesystems really want |
1541 | * a connected one, so try that first. | |
1542 | */ | |
f64410ec | 1543 | dentry = d_find_alias(inode); |
b127125d AV |
1544 | if (!dentry) |
1545 | dentry = d_find_any_alias(inode); | |
1546 | } | |
f64410ec PM |
1547 | /* |
1548 | * This can be hit on boot when a file is accessed | |
1549 | * before the policy is loaded. When we load policy we | |
1550 | * may find inodes that have no dentry on the | |
1551 | * sbsec->isec_head list. No reason to complain as | |
1552 | * these will get fixed up the next time we go through | |
1553 | * inode_doinit() with a dentry, before these inodes | |
1554 | * could be used again by userspace. | |
1555 | */ | |
1556 | if (!dentry) | |
9287aed2 AG |
1557 | goto out; |
1558 | rc = selinux_genfs_get_sid(dentry, sclass, | |
134509d5 | 1559 | sbsec->flags, &sid); |
b754026b OM |
1560 | if (rc) { |
1561 | dput(dentry); | |
9287aed2 | 1562 | goto out; |
b754026b OM |
1563 | } |
1564 | ||
1565 | if ((sbsec->flags & SE_SBGENFS_XATTR) && | |
1566 | (inode->i_opflags & IOP_XATTR)) { | |
1567 | rc = inode_doinit_use_xattr(inode, dentry, | |
1568 | sid, &sid); | |
1569 | if (rc) { | |
1570 | dput(dentry); | |
1571 | goto out; | |
1572 | } | |
1573 | } | |
1574 | dput(dentry); | |
1da177e4 LT |
1575 | } |
1576 | break; | |
1577 | } | |
1578 | ||
9287aed2 AG |
1579 | out: |
1580 | spin_lock(&isec->lock); | |
1581 | if (isec->initialized == LABEL_PENDING) { | |
1582 | if (!sid || rc) { | |
1583 | isec->initialized = LABEL_INVALID; | |
1584 | goto out_unlock; | |
1585 | } | |
1586 | ||
1587 | isec->initialized = LABEL_INITIALIZED; | |
1588 | isec->sid = sid; | |
1589 | } | |
1da177e4 | 1590 | |
23970741 | 1591 | out_unlock: |
9287aed2 | 1592 | spin_unlock(&isec->lock); |
1da177e4 LT |
1593 | return rc; |
1594 | } | |
1595 | ||
1596 | /* Convert a Linux signal to an access vector. */ | |
1597 | static inline u32 signal_to_av(int sig) | |
1598 | { | |
1599 | u32 perm = 0; | |
1600 | ||
1601 | switch (sig) { | |
1602 | case SIGCHLD: | |
1603 | /* Commonly granted from child to parent. */ | |
1604 | perm = PROCESS__SIGCHLD; | |
1605 | break; | |
1606 | case SIGKILL: | |
1607 | /* Cannot be caught or ignored */ | |
1608 | perm = PROCESS__SIGKILL; | |
1609 | break; | |
1610 | case SIGSTOP: | |
1611 | /* Cannot be caught or ignored */ | |
1612 | perm = PROCESS__SIGSTOP; | |
1613 | break; | |
1614 | default: | |
1615 | /* All other signals. */ | |
1616 | perm = PROCESS__SIGNAL; | |
1617 | break; | |
1618 | } | |
1619 | ||
1620 | return perm; | |
1621 | } | |
1622 | ||
b68e418c SS |
1623 | #if CAP_LAST_CAP > 63 |
1624 | #error Fix SELinux to handle capabilities > 63. | |
1625 | #endif | |
1626 | ||
1da177e4 | 1627 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1628 | static int cred_has_capability(const struct cred *cred, |
c1a85a00 | 1629 | int cap, unsigned int opts, bool initns) |
1da177e4 | 1630 | { |
2bf49690 | 1631 | struct common_audit_data ad; |
06112163 | 1632 | struct av_decision avd; |
b68e418c | 1633 | u16 sclass; |
3699c53c | 1634 | u32 sid = cred_sid(cred); |
b68e418c | 1635 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1636 | int rc; |
1da177e4 | 1637 | |
50c205f5 | 1638 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1639 | ad.u.cap = cap; |
1640 | ||
b68e418c SS |
1641 | switch (CAP_TO_INDEX(cap)) { |
1642 | case 0: | |
8e4ff6f2 | 1643 | sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; |
b68e418c SS |
1644 | break; |
1645 | case 1: | |
8e4ff6f2 | 1646 | sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; |
b68e418c SS |
1647 | break; |
1648 | default: | |
c103a91e | 1649 | pr_err("SELinux: out of range capability %d\n", cap); |
b68e418c | 1650 | BUG(); |
a35c6c83 | 1651 | return -EINVAL; |
b68e418c | 1652 | } |
06112163 | 1653 | |
6b6bc620 SS |
1654 | rc = avc_has_perm_noaudit(&selinux_state, |
1655 | sid, sid, sclass, av, 0, &avd); | |
c1a85a00 | 1656 | if (!(opts & CAP_OPT_NOAUDIT)) { |
6b6bc620 SS |
1657 | int rc2 = avc_audit(&selinux_state, |
1658 | sid, sid, sclass, av, &avd, rc, &ad, 0); | |
9ade0cf4 EP |
1659 | if (rc2) |
1660 | return rc2; | |
1661 | } | |
06112163 | 1662 | return rc; |
1da177e4 LT |
1663 | } |
1664 | ||
1da177e4 LT |
1665 | /* Check whether a task has a particular permission to an inode. |
1666 | The 'adp' parameter is optional and allows other audit | |
1667 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1668 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1669 | struct inode *inode, |
1670 | u32 perms, | |
19e49834 | 1671 | struct common_audit_data *adp) |
1da177e4 | 1672 | { |
1da177e4 | 1673 | struct inode_security_struct *isec; |
275bb41e | 1674 | u32 sid; |
1da177e4 | 1675 | |
e0e81739 DH |
1676 | validate_creds(cred); |
1677 | ||
828dfe1d | 1678 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1679 | return 0; |
1680 | ||
88e67f3b | 1681 | sid = cred_sid(cred); |
80788c22 | 1682 | isec = selinux_inode(inode); |
1da177e4 | 1683 | |
6b6bc620 SS |
1684 | return avc_has_perm(&selinux_state, |
1685 | sid, isec->sid, isec->sclass, perms, adp); | |
1da177e4 LT |
1686 | } |
1687 | ||
1688 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1689 | the dentry to help the auditing code to more easily generate the | |
1690 | pathname if needed. */ | |
88e67f3b | 1691 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1692 | struct dentry *dentry, |
1693 | u32 av) | |
1694 | { | |
c6f493d6 | 1695 | struct inode *inode = d_backing_inode(dentry); |
2bf49690 | 1696 | struct common_audit_data ad; |
88e67f3b | 1697 | |
50c205f5 | 1698 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1699 | ad.u.dentry = dentry; |
5d226df4 | 1700 | __inode_security_revalidate(inode, dentry, true); |
19e49834 | 1701 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1702 | } |
1703 | ||
1704 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1705 | the path to help the auditing code to more easily generate the | |
1706 | pathname if needed. */ | |
1707 | static inline int path_has_perm(const struct cred *cred, | |
3f7036a0 | 1708 | const struct path *path, |
2875fa00 EP |
1709 | u32 av) |
1710 | { | |
c6f493d6 | 1711 | struct inode *inode = d_backing_inode(path->dentry); |
2875fa00 EP |
1712 | struct common_audit_data ad; |
1713 | ||
50c205f5 | 1714 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1715 | ad.u.path = *path; |
5d226df4 | 1716 | __inode_security_revalidate(inode, path->dentry, true); |
19e49834 | 1717 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1718 | } |
1719 | ||
13f8e981 DH |
1720 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1721 | static inline int file_path_has_perm(const struct cred *cred, | |
1722 | struct file *file, | |
1723 | u32 av) | |
1724 | { | |
1725 | struct common_audit_data ad; | |
1726 | ||
43af5de7 VG |
1727 | ad.type = LSM_AUDIT_DATA_FILE; |
1728 | ad.u.file = file; | |
19e49834 | 1729 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1730 | } |
1731 | ||
f66e448c CF |
1732 | #ifdef CONFIG_BPF_SYSCALL |
1733 | static int bpf_fd_pass(struct file *file, u32 sid); | |
1734 | #endif | |
1735 | ||
1da177e4 LT |
1736 | /* Check whether a task can use an open file descriptor to |
1737 | access an inode in a given way. Check access to the | |
1738 | descriptor itself, and then use dentry_has_perm to | |
1739 | check a particular permission to the file. | |
1740 | Access to the descriptor is implicitly granted if it | |
1741 | has the same SID as the process. If av is zero, then | |
1742 | access to the file is not checked, e.g. for cases | |
1743 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1744 | static int file_has_perm(const struct cred *cred, |
1745 | struct file *file, | |
1746 | u32 av) | |
1da177e4 | 1747 | { |
bb6c6b02 | 1748 | struct file_security_struct *fsec = selinux_file(file); |
496ad9aa | 1749 | struct inode *inode = file_inode(file); |
2bf49690 | 1750 | struct common_audit_data ad; |
88e67f3b | 1751 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1752 | int rc; |
1753 | ||
43af5de7 VG |
1754 | ad.type = LSM_AUDIT_DATA_FILE; |
1755 | ad.u.file = file; | |
1da177e4 | 1756 | |
275bb41e | 1757 | if (sid != fsec->sid) { |
6b6bc620 SS |
1758 | rc = avc_has_perm(&selinux_state, |
1759 | sid, fsec->sid, | |
1da177e4 LT |
1760 | SECCLASS_FD, |
1761 | FD__USE, | |
1762 | &ad); | |
1763 | if (rc) | |
88e67f3b | 1764 | goto out; |
1da177e4 LT |
1765 | } |
1766 | ||
f66e448c CF |
1767 | #ifdef CONFIG_BPF_SYSCALL |
1768 | rc = bpf_fd_pass(file, cred_sid(cred)); | |
1769 | if (rc) | |
1770 | return rc; | |
1771 | #endif | |
1772 | ||
1da177e4 | 1773 | /* av is zero if only checking access to the descriptor. */ |
88e67f3b | 1774 | rc = 0; |
1da177e4 | 1775 | if (av) |
19e49834 | 1776 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1777 | |
88e67f3b DH |
1778 | out: |
1779 | return rc; | |
1da177e4 LT |
1780 | } |
1781 | ||
c3c188b2 DH |
1782 | /* |
1783 | * Determine the label for an inode that might be unioned. | |
1784 | */ | |
c957f6df VG |
1785 | static int |
1786 | selinux_determine_inode_label(const struct task_security_struct *tsec, | |
1787 | struct inode *dir, | |
1788 | const struct qstr *name, u16 tclass, | |
1789 | u32 *_new_isid) | |
c3c188b2 DH |
1790 | { |
1791 | const struct superblock_security_struct *sbsec = dir->i_sb->s_security; | |
c3c188b2 DH |
1792 | |
1793 | if ((sbsec->flags & SE_SBINITIALIZED) && | |
1794 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { | |
1795 | *_new_isid = sbsec->mntpoint_sid; | |
1796 | } else if ((sbsec->flags & SBLABEL_MNT) && | |
1797 | tsec->create_sid) { | |
1798 | *_new_isid = tsec->create_sid; | |
1799 | } else { | |
20cdef8d | 1800 | const struct inode_security_struct *dsec = inode_security(dir); |
aa8e712c SS |
1801 | return security_transition_sid(&selinux_state, tsec->sid, |
1802 | dsec->sid, tclass, | |
c3c188b2 DH |
1803 | name, _new_isid); |
1804 | } | |
1805 | ||
1806 | return 0; | |
1807 | } | |
1808 | ||
1da177e4 LT |
1809 | /* Check whether a task can create a file. */ |
1810 | static int may_create(struct inode *dir, | |
1811 | struct dentry *dentry, | |
1812 | u16 tclass) | |
1813 | { | |
0c6cfa62 | 1814 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
1da177e4 LT |
1815 | struct inode_security_struct *dsec; |
1816 | struct superblock_security_struct *sbsec; | |
275bb41e | 1817 | u32 sid, newsid; |
2bf49690 | 1818 | struct common_audit_data ad; |
1da177e4 LT |
1819 | int rc; |
1820 | ||
83da53c5 | 1821 | dsec = inode_security(dir); |
1da177e4 LT |
1822 | sbsec = dir->i_sb->s_security; |
1823 | ||
275bb41e | 1824 | sid = tsec->sid; |
275bb41e | 1825 | |
50c205f5 | 1826 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1827 | ad.u.dentry = dentry; |
1da177e4 | 1828 | |
6b6bc620 SS |
1829 | rc = avc_has_perm(&selinux_state, |
1830 | sid, dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
1831 | DIR__ADD_NAME | DIR__SEARCH, |
1832 | &ad); | |
1833 | if (rc) | |
1834 | return rc; | |
1835 | ||
0c6cfa62 | 1836 | rc = selinux_determine_inode_label(selinux_cred(current_cred()), dir, |
c957f6df | 1837 | &dentry->d_name, tclass, &newsid); |
c3c188b2 DH |
1838 | if (rc) |
1839 | return rc; | |
1da177e4 | 1840 | |
6b6bc620 SS |
1841 | rc = avc_has_perm(&selinux_state, |
1842 | sid, newsid, tclass, FILE__CREATE, &ad); | |
1da177e4 LT |
1843 | if (rc) |
1844 | return rc; | |
1845 | ||
6b6bc620 SS |
1846 | return avc_has_perm(&selinux_state, |
1847 | newsid, sbsec->sid, | |
1da177e4 LT |
1848 | SECCLASS_FILESYSTEM, |
1849 | FILESYSTEM__ASSOCIATE, &ad); | |
1850 | } | |
1851 | ||
828dfe1d EP |
1852 | #define MAY_LINK 0 |
1853 | #define MAY_UNLINK 1 | |
1854 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1855 | |
1856 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1857 | static int may_link(struct inode *dir, | |
1858 | struct dentry *dentry, | |
1859 | int kind) | |
1860 | ||
1861 | { | |
1da177e4 | 1862 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 1863 | struct common_audit_data ad; |
275bb41e | 1864 | u32 sid = current_sid(); |
1da177e4 LT |
1865 | u32 av; |
1866 | int rc; | |
1867 | ||
83da53c5 AG |
1868 | dsec = inode_security(dir); |
1869 | isec = backing_inode_security(dentry); | |
1da177e4 | 1870 | |
50c205f5 | 1871 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1872 | ad.u.dentry = dentry; |
1da177e4 LT |
1873 | |
1874 | av = DIR__SEARCH; | |
1875 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
6b6bc620 SS |
1876 | rc = avc_has_perm(&selinux_state, |
1877 | sid, dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
1878 | if (rc) |
1879 | return rc; | |
1880 | ||
1881 | switch (kind) { | |
1882 | case MAY_LINK: | |
1883 | av = FILE__LINK; | |
1884 | break; | |
1885 | case MAY_UNLINK: | |
1886 | av = FILE__UNLINK; | |
1887 | break; | |
1888 | case MAY_RMDIR: | |
1889 | av = DIR__RMDIR; | |
1890 | break; | |
1891 | default: | |
c103a91e | 1892 | pr_warn("SELinux: %s: unrecognized kind %d\n", |
744ba35e | 1893 | __func__, kind); |
1da177e4 LT |
1894 | return 0; |
1895 | } | |
1896 | ||
6b6bc620 SS |
1897 | rc = avc_has_perm(&selinux_state, |
1898 | sid, isec->sid, isec->sclass, av, &ad); | |
1da177e4 LT |
1899 | return rc; |
1900 | } | |
1901 | ||
1902 | static inline int may_rename(struct inode *old_dir, | |
1903 | struct dentry *old_dentry, | |
1904 | struct inode *new_dir, | |
1905 | struct dentry *new_dentry) | |
1906 | { | |
1da177e4 | 1907 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 1908 | struct common_audit_data ad; |
275bb41e | 1909 | u32 sid = current_sid(); |
1da177e4 LT |
1910 | u32 av; |
1911 | int old_is_dir, new_is_dir; | |
1912 | int rc; | |
1913 | ||
83da53c5 AG |
1914 | old_dsec = inode_security(old_dir); |
1915 | old_isec = backing_inode_security(old_dentry); | |
e36cb0b8 | 1916 | old_is_dir = d_is_dir(old_dentry); |
83da53c5 | 1917 | new_dsec = inode_security(new_dir); |
1da177e4 | 1918 | |
50c205f5 | 1919 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 1920 | |
a269434d | 1921 | ad.u.dentry = old_dentry; |
6b6bc620 SS |
1922 | rc = avc_has_perm(&selinux_state, |
1923 | sid, old_dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
1924 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
1925 | if (rc) | |
1926 | return rc; | |
6b6bc620 SS |
1927 | rc = avc_has_perm(&selinux_state, |
1928 | sid, old_isec->sid, | |
1da177e4 LT |
1929 | old_isec->sclass, FILE__RENAME, &ad); |
1930 | if (rc) | |
1931 | return rc; | |
1932 | if (old_is_dir && new_dir != old_dir) { | |
6b6bc620 SS |
1933 | rc = avc_has_perm(&selinux_state, |
1934 | sid, old_isec->sid, | |
1da177e4 LT |
1935 | old_isec->sclass, DIR__REPARENT, &ad); |
1936 | if (rc) | |
1937 | return rc; | |
1938 | } | |
1939 | ||
a269434d | 1940 | ad.u.dentry = new_dentry; |
1da177e4 | 1941 | av = DIR__ADD_NAME | DIR__SEARCH; |
2c616d4d | 1942 | if (d_is_positive(new_dentry)) |
1da177e4 | 1943 | av |= DIR__REMOVE_NAME; |
6b6bc620 SS |
1944 | rc = avc_has_perm(&selinux_state, |
1945 | sid, new_dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
1946 | if (rc) |
1947 | return rc; | |
2c616d4d | 1948 | if (d_is_positive(new_dentry)) { |
83da53c5 | 1949 | new_isec = backing_inode_security(new_dentry); |
e36cb0b8 | 1950 | new_is_dir = d_is_dir(new_dentry); |
6b6bc620 SS |
1951 | rc = avc_has_perm(&selinux_state, |
1952 | sid, new_isec->sid, | |
1da177e4 LT |
1953 | new_isec->sclass, |
1954 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1955 | if (rc) | |
1956 | return rc; | |
1957 | } | |
1958 | ||
1959 | return 0; | |
1960 | } | |
1961 | ||
1962 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 1963 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
1964 | struct super_block *sb, |
1965 | u32 perms, | |
2bf49690 | 1966 | struct common_audit_data *ad) |
1da177e4 | 1967 | { |
1da177e4 | 1968 | struct superblock_security_struct *sbsec; |
88e67f3b | 1969 | u32 sid = cred_sid(cred); |
1da177e4 | 1970 | |
1da177e4 | 1971 | sbsec = sb->s_security; |
6b6bc620 SS |
1972 | return avc_has_perm(&selinux_state, |
1973 | sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); | |
1da177e4 LT |
1974 | } |
1975 | ||
1976 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1977 | static inline u32 file_mask_to_av(int mode, int mask) | |
1978 | { | |
1979 | u32 av = 0; | |
1980 | ||
dba19c60 | 1981 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
1982 | if (mask & MAY_EXEC) |
1983 | av |= FILE__EXECUTE; | |
1984 | if (mask & MAY_READ) | |
1985 | av |= FILE__READ; | |
1986 | ||
1987 | if (mask & MAY_APPEND) | |
1988 | av |= FILE__APPEND; | |
1989 | else if (mask & MAY_WRITE) | |
1990 | av |= FILE__WRITE; | |
1991 | ||
1992 | } else { | |
1993 | if (mask & MAY_EXEC) | |
1994 | av |= DIR__SEARCH; | |
1995 | if (mask & MAY_WRITE) | |
1996 | av |= DIR__WRITE; | |
1997 | if (mask & MAY_READ) | |
1998 | av |= DIR__READ; | |
1999 | } | |
2000 | ||
2001 | return av; | |
2002 | } | |
2003 | ||
8b6a5a37 EP |
2004 | /* Convert a Linux file to an access vector. */ |
2005 | static inline u32 file_to_av(struct file *file) | |
2006 | { | |
2007 | u32 av = 0; | |
2008 | ||
2009 | if (file->f_mode & FMODE_READ) | |
2010 | av |= FILE__READ; | |
2011 | if (file->f_mode & FMODE_WRITE) { | |
2012 | if (file->f_flags & O_APPEND) | |
2013 | av |= FILE__APPEND; | |
2014 | else | |
2015 | av |= FILE__WRITE; | |
2016 | } | |
2017 | if (!av) { | |
2018 | /* | |
2019 | * Special file opened with flags 3 for ioctl-only use. | |
2020 | */ | |
2021 | av = FILE__IOCTL; | |
2022 | } | |
2023 | ||
2024 | return av; | |
2025 | } | |
2026 | ||
b0c636b9 | 2027 | /* |
8b6a5a37 | 2028 | * Convert a file to an access vector and include the correct open |
b0c636b9 EP |
2029 | * open permission. |
2030 | */ | |
8b6a5a37 | 2031 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 2032 | { |
8b6a5a37 | 2033 | u32 av = file_to_av(file); |
ccb54478 | 2034 | struct inode *inode = file_inode(file); |
b0c636b9 | 2035 | |
aa8e712c SS |
2036 | if (selinux_policycap_openperm() && |
2037 | inode->i_sb->s_magic != SOCKFS_MAGIC) | |
49b7b8de EP |
2038 | av |= FILE__OPEN; |
2039 | ||
b0c636b9 EP |
2040 | return av; |
2041 | } | |
2042 | ||
1da177e4 LT |
2043 | /* Hook functions begin here. */ |
2044 | ||
79af7307 SS |
2045 | static int selinux_binder_set_context_mgr(struct task_struct *mgr) |
2046 | { | |
2047 | u32 mysid = current_sid(); | |
2048 | u32 mgrsid = task_sid(mgr); | |
2049 | ||
6b6bc620 SS |
2050 | return avc_has_perm(&selinux_state, |
2051 | mysid, mgrsid, SECCLASS_BINDER, | |
79af7307 SS |
2052 | BINDER__SET_CONTEXT_MGR, NULL); |
2053 | } | |
2054 | ||
2055 | static int selinux_binder_transaction(struct task_struct *from, | |
2056 | struct task_struct *to) | |
2057 | { | |
2058 | u32 mysid = current_sid(); | |
2059 | u32 fromsid = task_sid(from); | |
2060 | u32 tosid = task_sid(to); | |
2061 | int rc; | |
2062 | ||
2063 | if (mysid != fromsid) { | |
6b6bc620 SS |
2064 | rc = avc_has_perm(&selinux_state, |
2065 | mysid, fromsid, SECCLASS_BINDER, | |
79af7307 SS |
2066 | BINDER__IMPERSONATE, NULL); |
2067 | if (rc) | |
2068 | return rc; | |
2069 | } | |
2070 | ||
6b6bc620 SS |
2071 | return avc_has_perm(&selinux_state, |
2072 | fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, | |
79af7307 SS |
2073 | NULL); |
2074 | } | |
2075 | ||
2076 | static int selinux_binder_transfer_binder(struct task_struct *from, | |
2077 | struct task_struct *to) | |
2078 | { | |
2079 | u32 fromsid = task_sid(from); | |
2080 | u32 tosid = task_sid(to); | |
2081 | ||
6b6bc620 SS |
2082 | return avc_has_perm(&selinux_state, |
2083 | fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, | |
79af7307 SS |
2084 | NULL); |
2085 | } | |
2086 | ||
2087 | static int selinux_binder_transfer_file(struct task_struct *from, | |
2088 | struct task_struct *to, | |
2089 | struct file *file) | |
2090 | { | |
2091 | u32 sid = task_sid(to); | |
bb6c6b02 | 2092 | struct file_security_struct *fsec = selinux_file(file); |
83da53c5 | 2093 | struct dentry *dentry = file->f_path.dentry; |
20cdef8d | 2094 | struct inode_security_struct *isec; |
79af7307 SS |
2095 | struct common_audit_data ad; |
2096 | int rc; | |
2097 | ||
2098 | ad.type = LSM_AUDIT_DATA_PATH; | |
2099 | ad.u.path = file->f_path; | |
2100 | ||
2101 | if (sid != fsec->sid) { | |
6b6bc620 SS |
2102 | rc = avc_has_perm(&selinux_state, |
2103 | sid, fsec->sid, | |
79af7307 SS |
2104 | SECCLASS_FD, |
2105 | FD__USE, | |
2106 | &ad); | |
2107 | if (rc) | |
2108 | return rc; | |
2109 | } | |
2110 | ||
f66e448c CF |
2111 | #ifdef CONFIG_BPF_SYSCALL |
2112 | rc = bpf_fd_pass(file, sid); | |
2113 | if (rc) | |
2114 | return rc; | |
2115 | #endif | |
2116 | ||
83da53c5 | 2117 | if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
79af7307 SS |
2118 | return 0; |
2119 | ||
20cdef8d | 2120 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
2121 | return avc_has_perm(&selinux_state, |
2122 | sid, isec->sid, isec->sclass, file_to_av(file), | |
79af7307 SS |
2123 | &ad); |
2124 | } | |
2125 | ||
9e48858f | 2126 | static int selinux_ptrace_access_check(struct task_struct *child, |
5cd9c58f | 2127 | unsigned int mode) |
1da177e4 | 2128 | { |
be0554c9 SS |
2129 | u32 sid = current_sid(); |
2130 | u32 csid = task_sid(child); | |
2131 | ||
2132 | if (mode & PTRACE_MODE_READ) | |
6b6bc620 SS |
2133 | return avc_has_perm(&selinux_state, |
2134 | sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 | 2135 | |
6b6bc620 SS |
2136 | return avc_has_perm(&selinux_state, |
2137 | sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); | |
5cd9c58f DH |
2138 | } |
2139 | ||
2140 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
2141 | { | |
6b6bc620 SS |
2142 | return avc_has_perm(&selinux_state, |
2143 | task_sid(parent), current_sid(), SECCLASS_PROCESS, | |
be0554c9 | 2144 | PROCESS__PTRACE, NULL); |
1da177e4 LT |
2145 | } |
2146 | ||
2147 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 2148 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 | 2149 | { |
6b6bc620 SS |
2150 | return avc_has_perm(&selinux_state, |
2151 | current_sid(), task_sid(target), SECCLASS_PROCESS, | |
be0554c9 | 2152 | PROCESS__GETCAP, NULL); |
1da177e4 LT |
2153 | } |
2154 | ||
d84f4f99 DH |
2155 | static int selinux_capset(struct cred *new, const struct cred *old, |
2156 | const kernel_cap_t *effective, | |
2157 | const kernel_cap_t *inheritable, | |
2158 | const kernel_cap_t *permitted) | |
1da177e4 | 2159 | { |
6b6bc620 SS |
2160 | return avc_has_perm(&selinux_state, |
2161 | cred_sid(old), cred_sid(new), SECCLASS_PROCESS, | |
be0554c9 | 2162 | PROCESS__SETCAP, NULL); |
1da177e4 LT |
2163 | } |
2164 | ||
5626d3e8 JM |
2165 | /* |
2166 | * (This comment used to live with the selinux_task_setuid hook, | |
2167 | * which was removed). | |
2168 | * | |
2169 | * Since setuid only affects the current process, and since the SELinux | |
2170 | * controls are not based on the Linux identity attributes, SELinux does not | |
2171 | * need to control this operation. However, SELinux does control the use of | |
2172 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
2173 | */ | |
2174 | ||
6a9de491 | 2175 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
c1a85a00 | 2176 | int cap, unsigned int opts) |
1da177e4 | 2177 | { |
c1a85a00 | 2178 | return cred_has_capability(cred, cap, opts, ns == &init_user_ns); |
1da177e4 LT |
2179 | } |
2180 | ||
1da177e4 LT |
2181 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
2182 | { | |
88e67f3b | 2183 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2184 | int rc = 0; |
2185 | ||
2186 | if (!sb) | |
2187 | return 0; | |
2188 | ||
2189 | switch (cmds) { | |
828dfe1d EP |
2190 | case Q_SYNC: |
2191 | case Q_QUOTAON: | |
2192 | case Q_QUOTAOFF: | |
2193 | case Q_SETINFO: | |
2194 | case Q_SETQUOTA: | |
88e67f3b | 2195 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
2196 | break; |
2197 | case Q_GETFMT: | |
2198 | case Q_GETINFO: | |
2199 | case Q_GETQUOTA: | |
88e67f3b | 2200 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
2201 | break; |
2202 | default: | |
2203 | rc = 0; /* let the kernel handle invalid cmds */ | |
2204 | break; | |
1da177e4 LT |
2205 | } |
2206 | return rc; | |
2207 | } | |
2208 | ||
2209 | static int selinux_quota_on(struct dentry *dentry) | |
2210 | { | |
88e67f3b DH |
2211 | const struct cred *cred = current_cred(); |
2212 | ||
2875fa00 | 2213 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
2214 | } |
2215 | ||
12b3052c | 2216 | static int selinux_syslog(int type) |
1da177e4 | 2217 | { |
1da177e4 | 2218 | switch (type) { |
d78ca3cd KC |
2219 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2220 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
6b6bc620 SS |
2221 | return avc_has_perm(&selinux_state, |
2222 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2223 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); |
d78ca3cd KC |
2224 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2225 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2226 | /* Set level of messages printed to console */ | |
2227 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
6b6bc620 SS |
2228 | return avc_has_perm(&selinux_state, |
2229 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 SS |
2230 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, |
2231 | NULL); | |
1da177e4 | 2232 | } |
be0554c9 | 2233 | /* All other syslog types */ |
6b6bc620 SS |
2234 | return avc_has_perm(&selinux_state, |
2235 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2236 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); |
1da177e4 LT |
2237 | } |
2238 | ||
2239 | /* | |
2240 | * Check that a process has enough memory to allocate a new virtual | |
2241 | * mapping. 0 means there is enough memory for the allocation to | |
2242 | * succeed and -ENOMEM implies there is not. | |
2243 | * | |
1da177e4 LT |
2244 | * Do not audit the selinux permission check, as this is applied to all |
2245 | * processes that allocate mappings. | |
2246 | */ | |
34b4e4aa | 2247 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2248 | { |
2249 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2250 | |
b1d9e6b0 | 2251 | rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, |
c1a85a00 | 2252 | CAP_OPT_NOAUDIT, true); |
1da177e4 LT |
2253 | if (rc == 0) |
2254 | cap_sys_admin = 1; | |
2255 | ||
b1d9e6b0 | 2256 | return cap_sys_admin; |
1da177e4 LT |
2257 | } |
2258 | ||
2259 | /* binprm security operations */ | |
2260 | ||
be0554c9 | 2261 | static u32 ptrace_parent_sid(void) |
0c6181cb PM |
2262 | { |
2263 | u32 sid = 0; | |
2264 | struct task_struct *tracer; | |
2265 | ||
2266 | rcu_read_lock(); | |
be0554c9 | 2267 | tracer = ptrace_parent(current); |
0c6181cb PM |
2268 | if (tracer) |
2269 | sid = task_sid(tracer); | |
2270 | rcu_read_unlock(); | |
2271 | ||
2272 | return sid; | |
2273 | } | |
2274 | ||
7b0d0b40 SS |
2275 | static int check_nnp_nosuid(const struct linux_binprm *bprm, |
2276 | const struct task_security_struct *old_tsec, | |
2277 | const struct task_security_struct *new_tsec) | |
2278 | { | |
2279 | int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); | |
380cf5ba | 2280 | int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); |
7b0d0b40 | 2281 | int rc; |
af63f419 | 2282 | u32 av; |
7b0d0b40 SS |
2283 | |
2284 | if (!nnp && !nosuid) | |
2285 | return 0; /* neither NNP nor nosuid */ | |
2286 | ||
2287 | if (new_tsec->sid == old_tsec->sid) | |
2288 | return 0; /* No change in credentials */ | |
2289 | ||
2290 | /* | |
af63f419 SS |
2291 | * If the policy enables the nnp_nosuid_transition policy capability, |
2292 | * then we permit transitions under NNP or nosuid if the | |
2293 | * policy allows the corresponding permission between | |
2294 | * the old and new contexts. | |
7b0d0b40 | 2295 | */ |
aa8e712c | 2296 | if (selinux_policycap_nnp_nosuid_transition()) { |
af63f419 | 2297 | av = 0; |
7b0d0b40 | 2298 | if (nnp) |
af63f419 SS |
2299 | av |= PROCESS2__NNP_TRANSITION; |
2300 | if (nosuid) | |
2301 | av |= PROCESS2__NOSUID_TRANSITION; | |
6b6bc620 SS |
2302 | rc = avc_has_perm(&selinux_state, |
2303 | old_tsec->sid, new_tsec->sid, | |
af63f419 SS |
2304 | SECCLASS_PROCESS2, av, NULL); |
2305 | if (!rc) | |
2306 | return 0; | |
7b0d0b40 | 2307 | } |
af63f419 SS |
2308 | |
2309 | /* | |
2310 | * We also permit NNP or nosuid transitions to bounded SIDs, | |
2311 | * i.e. SIDs that are guaranteed to only be allowed a subset | |
2312 | * of the permissions of the current SID. | |
2313 | */ | |
aa8e712c SS |
2314 | rc = security_bounded_transition(&selinux_state, old_tsec->sid, |
2315 | new_tsec->sid); | |
af63f419 SS |
2316 | if (!rc) |
2317 | return 0; | |
2318 | ||
2319 | /* | |
2320 | * On failure, preserve the errno values for NNP vs nosuid. | |
2321 | * NNP: Operation not permitted for caller. | |
2322 | * nosuid: Permission denied to file. | |
2323 | */ | |
2324 | if (nnp) | |
2325 | return -EPERM; | |
2326 | return -EACCES; | |
7b0d0b40 SS |
2327 | } |
2328 | ||
a6f76f23 | 2329 | static int selinux_bprm_set_creds(struct linux_binprm *bprm) |
1da177e4 | 2330 | { |
a6f76f23 DH |
2331 | const struct task_security_struct *old_tsec; |
2332 | struct task_security_struct *new_tsec; | |
1da177e4 | 2333 | struct inode_security_struct *isec; |
2bf49690 | 2334 | struct common_audit_data ad; |
496ad9aa | 2335 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2336 | int rc; |
2337 | ||
a6f76f23 DH |
2338 | /* SELinux context only depends on initial program or script and not |
2339 | * the script interpreter */ | |
ddb4a144 | 2340 | if (bprm->called_set_creds) |
1da177e4 LT |
2341 | return 0; |
2342 | ||
0c6cfa62 CS |
2343 | old_tsec = selinux_cred(current_cred()); |
2344 | new_tsec = selinux_cred(bprm->cred); | |
83da53c5 | 2345 | isec = inode_security(inode); |
1da177e4 LT |
2346 | |
2347 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2348 | new_tsec->sid = old_tsec->sid; |
2349 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2350 | |
28eba5bf | 2351 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2352 | new_tsec->create_sid = 0; |
2353 | new_tsec->keycreate_sid = 0; | |
2354 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2355 | |
a6f76f23 DH |
2356 | if (old_tsec->exec_sid) { |
2357 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2358 | /* Reset exec SID on execve. */ |
a6f76f23 | 2359 | new_tsec->exec_sid = 0; |
259e5e6c | 2360 | |
7b0d0b40 SS |
2361 | /* Fail on NNP or nosuid if not an allowed transition. */ |
2362 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2363 | if (rc) | |
2364 | return rc; | |
1da177e4 LT |
2365 | } else { |
2366 | /* Check for a default transition on this program. */ | |
aa8e712c SS |
2367 | rc = security_transition_sid(&selinux_state, old_tsec->sid, |
2368 | isec->sid, SECCLASS_PROCESS, NULL, | |
652bb9b0 | 2369 | &new_tsec->sid); |
1da177e4 LT |
2370 | if (rc) |
2371 | return rc; | |
7b0d0b40 SS |
2372 | |
2373 | /* | |
2374 | * Fallback to old SID on NNP or nosuid if not an allowed | |
2375 | * transition. | |
2376 | */ | |
2377 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2378 | if (rc) | |
2379 | new_tsec->sid = old_tsec->sid; | |
1da177e4 LT |
2380 | } |
2381 | ||
43af5de7 VG |
2382 | ad.type = LSM_AUDIT_DATA_FILE; |
2383 | ad.u.file = bprm->file; | |
1da177e4 | 2384 | |
a6f76f23 | 2385 | if (new_tsec->sid == old_tsec->sid) { |
6b6bc620 SS |
2386 | rc = avc_has_perm(&selinux_state, |
2387 | old_tsec->sid, isec->sid, | |
1da177e4 LT |
2388 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2389 | if (rc) | |
2390 | return rc; | |
2391 | } else { | |
2392 | /* Check permissions for the transition. */ | |
6b6bc620 SS |
2393 | rc = avc_has_perm(&selinux_state, |
2394 | old_tsec->sid, new_tsec->sid, | |
1da177e4 LT |
2395 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2396 | if (rc) | |
2397 | return rc; | |
2398 | ||
6b6bc620 SS |
2399 | rc = avc_has_perm(&selinux_state, |
2400 | new_tsec->sid, isec->sid, | |
1da177e4 LT |
2401 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2402 | if (rc) | |
2403 | return rc; | |
2404 | ||
a6f76f23 DH |
2405 | /* Check for shared state */ |
2406 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
6b6bc620 SS |
2407 | rc = avc_has_perm(&selinux_state, |
2408 | old_tsec->sid, new_tsec->sid, | |
a6f76f23 DH |
2409 | SECCLASS_PROCESS, PROCESS__SHARE, |
2410 | NULL); | |
2411 | if (rc) | |
2412 | return -EPERM; | |
2413 | } | |
2414 | ||
2415 | /* Make sure that anyone attempting to ptrace over a task that | |
2416 | * changes its SID has the appropriate permit */ | |
9227dd2a | 2417 | if (bprm->unsafe & LSM_UNSAFE_PTRACE) { |
be0554c9 | 2418 | u32 ptsid = ptrace_parent_sid(); |
a6f76f23 | 2419 | if (ptsid != 0) { |
6b6bc620 SS |
2420 | rc = avc_has_perm(&selinux_state, |
2421 | ptsid, new_tsec->sid, | |
a6f76f23 DH |
2422 | SECCLASS_PROCESS, |
2423 | PROCESS__PTRACE, NULL); | |
2424 | if (rc) | |
2425 | return -EPERM; | |
2426 | } | |
2427 | } | |
1da177e4 | 2428 | |
a6f76f23 DH |
2429 | /* Clear any possibly unsafe personality bits on exec: */ |
2430 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
275bb41e | 2431 | |
1da177e4 LT |
2432 | /* Enable secure mode for SIDs transitions unless |
2433 | the noatsecure permission is granted between | |
2434 | the two SIDs, i.e. ahp returns 0. */ | |
6b6bc620 SS |
2435 | rc = avc_has_perm(&selinux_state, |
2436 | old_tsec->sid, new_tsec->sid, | |
62874c3a KC |
2437 | SECCLASS_PROCESS, PROCESS__NOATSECURE, |
2438 | NULL); | |
2439 | bprm->secureexec |= !!rc; | |
1da177e4 LT |
2440 | } |
2441 | ||
62874c3a | 2442 | return 0; |
1da177e4 LT |
2443 | } |
2444 | ||
c3c073f8 AV |
2445 | static int match_file(const void *p, struct file *file, unsigned fd) |
2446 | { | |
2447 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2448 | } | |
2449 | ||
1da177e4 | 2450 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2451 | static inline void flush_unauthorized_files(const struct cred *cred, |
2452 | struct files_struct *files) | |
1da177e4 | 2453 | { |
1da177e4 | 2454 | struct file *file, *devnull = NULL; |
b20c8122 | 2455 | struct tty_struct *tty; |
24ec839c | 2456 | int drop_tty = 0; |
c3c073f8 | 2457 | unsigned n; |
1da177e4 | 2458 | |
24ec839c | 2459 | tty = get_current_tty(); |
1da177e4 | 2460 | if (tty) { |
4a510969 | 2461 | spin_lock(&tty->files_lock); |
37dd0bd0 | 2462 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2463 | struct tty_file_private *file_priv; |
37dd0bd0 | 2464 | |
1da177e4 | 2465 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2466 | Use file_path_has_perm on the tty path directly |
2467 | rather than using file_has_perm, as this particular | |
2468 | open file may belong to another process and we are | |
2469 | only interested in the inode-based check here. */ | |
d996b62a NP |
2470 | file_priv = list_first_entry(&tty->tty_files, |
2471 | struct tty_file_private, list); | |
2472 | file = file_priv->file; | |
13f8e981 | 2473 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2474 | drop_tty = 1; |
1da177e4 | 2475 | } |
4a510969 | 2476 | spin_unlock(&tty->files_lock); |
452a00d2 | 2477 | tty_kref_put(tty); |
1da177e4 | 2478 | } |
98a27ba4 EB |
2479 | /* Reset controlling tty. */ |
2480 | if (drop_tty) | |
2481 | no_tty(); | |
1da177e4 LT |
2482 | |
2483 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2484 | n = iterate_fd(files, 0, match_file, cred); |
2485 | if (!n) /* none found? */ | |
2486 | return; | |
1da177e4 | 2487 | |
c3c073f8 | 2488 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2489 | if (IS_ERR(devnull)) |
2490 | devnull = NULL; | |
2491 | /* replace all the matching ones with this */ | |
2492 | do { | |
2493 | replace_fd(n - 1, devnull, 0); | |
2494 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2495 | if (devnull) | |
c3c073f8 | 2496 | fput(devnull); |
1da177e4 LT |
2497 | } |
2498 | ||
a6f76f23 DH |
2499 | /* |
2500 | * Prepare a process for imminent new credential changes due to exec | |
2501 | */ | |
2502 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2503 | { |
a6f76f23 DH |
2504 | struct task_security_struct *new_tsec; |
2505 | struct rlimit *rlim, *initrlim; | |
2506 | int rc, i; | |
d84f4f99 | 2507 | |
0c6cfa62 | 2508 | new_tsec = selinux_cred(bprm->cred); |
a6f76f23 DH |
2509 | if (new_tsec->sid == new_tsec->osid) |
2510 | return; | |
1da177e4 | 2511 | |
a6f76f23 DH |
2512 | /* Close files for which the new task SID is not authorized. */ |
2513 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2514 | |
a6f76f23 DH |
2515 | /* Always clear parent death signal on SID transitions. */ |
2516 | current->pdeath_signal = 0; | |
0356357c | 2517 | |
a6f76f23 DH |
2518 | /* Check whether the new SID can inherit resource limits from the old |
2519 | * SID. If not, reset all soft limits to the lower of the current | |
2520 | * task's hard limit and the init task's soft limit. | |
2521 | * | |
2522 | * Note that the setting of hard limits (even to lower them) can be | |
2523 | * controlled by the setrlimit check. The inclusion of the init task's | |
2524 | * soft limit into the computation is to avoid resetting soft limits | |
2525 | * higher than the default soft limit for cases where the default is | |
2526 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2527 | */ | |
6b6bc620 SS |
2528 | rc = avc_has_perm(&selinux_state, |
2529 | new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
a6f76f23 DH |
2530 | PROCESS__RLIMITINH, NULL); |
2531 | if (rc) { | |
eb2d55a3 ON |
2532 | /* protect against do_prlimit() */ |
2533 | task_lock(current); | |
a6f76f23 DH |
2534 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2535 | rlim = current->signal->rlim + i; | |
2536 | initrlim = init_task.signal->rlim + i; | |
2537 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2538 | } |
eb2d55a3 | 2539 | task_unlock(current); |
baa73d9e NP |
2540 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) |
2541 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2542 | } |
2543 | } | |
2544 | ||
2545 | /* | |
a6f76f23 DH |
2546 | * Clean up the process immediately after the installation of new credentials |
2547 | * due to exec | |
1da177e4 | 2548 | */ |
a6f76f23 | 2549 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2550 | { |
0c6cfa62 | 2551 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
a6f76f23 | 2552 | u32 osid, sid; |
ddbc7d06 | 2553 | int rc; |
1da177e4 | 2554 | |
a6f76f23 DH |
2555 | osid = tsec->osid; |
2556 | sid = tsec->sid; | |
2557 | ||
2558 | if (sid == osid) | |
1da177e4 LT |
2559 | return; |
2560 | ||
a6f76f23 DH |
2561 | /* Check whether the new SID can inherit signal state from the old SID. |
2562 | * If not, clear itimers to avoid subsequent signal generation and | |
2563 | * flush and unblock signals. | |
2564 | * | |
2565 | * This must occur _after_ the task SID has been updated so that any | |
2566 | * kill done after the flush will be checked against the new SID. | |
2567 | */ | |
6b6bc620 SS |
2568 | rc = avc_has_perm(&selinux_state, |
2569 | osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 | 2570 | if (rc) { |
ddbc7d06 AB |
2571 | clear_itimer(); |
2572 | ||
1da177e4 | 2573 | spin_lock_irq(¤t->sighand->siglock); |
9e7c8f8c ON |
2574 | if (!fatal_signal_pending(current)) { |
2575 | flush_sigqueue(¤t->pending); | |
2576 | flush_sigqueue(¤t->signal->shared_pending); | |
3bcac026 DH |
2577 | flush_signal_handlers(current, 1); |
2578 | sigemptyset(¤t->blocked); | |
9e7c8f8c | 2579 | recalc_sigpending(); |
3bcac026 | 2580 | } |
1da177e4 LT |
2581 | spin_unlock_irq(¤t->sighand->siglock); |
2582 | } | |
2583 | ||
a6f76f23 DH |
2584 | /* Wake up the parent if it is waiting so that it can recheck |
2585 | * wait permission to the new task SID. */ | |
ecd6de3c | 2586 | read_lock(&tasklist_lock); |
0b7570e7 | 2587 | __wake_up_parent(current, current->real_parent); |
ecd6de3c | 2588 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2589 | } |
2590 | ||
2591 | /* superblock security operations */ | |
2592 | ||
2593 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2594 | { | |
2595 | return superblock_alloc_security(sb); | |
2596 | } | |
2597 | ||
2598 | static void selinux_sb_free_security(struct super_block *sb) | |
2599 | { | |
2600 | superblock_free_security(sb); | |
2601 | } | |
2602 | ||
99dbbb59 | 2603 | static inline int opt_len(const char *s) |
1da177e4 | 2604 | { |
99dbbb59 AV |
2605 | bool open_quote = false; |
2606 | int len; | |
2607 | char c; | |
1da177e4 | 2608 | |
99dbbb59 AV |
2609 | for (len = 0; (c = s[len]) != '\0'; len++) { |
2610 | if (c == '"') | |
2611 | open_quote = !open_quote; | |
2612 | if (c == ',' && !open_quote) | |
2613 | break; | |
3528a953 | 2614 | } |
99dbbb59 | 2615 | return len; |
3528a953 CO |
2616 | } |
2617 | ||
99dbbb59 | 2618 | static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) |
1da177e4 | 2619 | { |
99dbbb59 AV |
2620 | char *from = options; |
2621 | char *to = options; | |
2622 | bool first = true; | |
fec63753 | 2623 | int rc; |
1da177e4 | 2624 | |
99dbbb59 AV |
2625 | while (1) { |
2626 | int len = opt_len(from); | |
fec63753 | 2627 | int token; |
99dbbb59 | 2628 | char *arg = NULL; |
1da177e4 | 2629 | |
99dbbb59 | 2630 | token = match_opt_prefix(from, len, &arg); |
1da177e4 | 2631 | |
99dbbb59 AV |
2632 | if (token != Opt_error) { |
2633 | char *p, *q; | |
1da177e4 | 2634 | |
99dbbb59 AV |
2635 | /* strip quotes */ |
2636 | if (arg) { | |
2637 | for (p = q = arg; p < from + len; p++) { | |
2638 | char c = *p; | |
2639 | if (c != '"') | |
2640 | *q++ = c; | |
2641 | } | |
2642 | arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); | |
fec63753 GZ |
2643 | if (!arg) { |
2644 | rc = -ENOMEM; | |
2645 | goto free_opt; | |
2646 | } | |
99dbbb59 AV |
2647 | } |
2648 | rc = selinux_add_opt(token, arg, mnt_opts); | |
2649 | if (unlikely(rc)) { | |
2650 | kfree(arg); | |
fec63753 | 2651 | goto free_opt; |
99dbbb59 AV |
2652 | } |
2653 | } else { | |
2654 | if (!first) { // copy with preceding comma | |
2655 | from--; | |
2656 | len++; | |
2657 | } | |
2658 | if (to != from) | |
2659 | memmove(to, from, len); | |
2660 | to += len; | |
2661 | first = false; | |
1da177e4 | 2662 | } |
99dbbb59 AV |
2663 | if (!from[len]) |
2664 | break; | |
2665 | from += len + 1; | |
2666 | } | |
2667 | *to = '\0'; | |
2668 | return 0; | |
fec63753 GZ |
2669 | |
2670 | free_opt: | |
2671 | if (*mnt_opts) { | |
2672 | selinux_free_mnt_opts(*mnt_opts); | |
2673 | *mnt_opts = NULL; | |
2674 | } | |
2675 | return rc; | |
1da177e4 LT |
2676 | } |
2677 | ||
204cc0cc | 2678 | static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) |
026eb167 | 2679 | { |
bd323655 | 2680 | struct selinux_mnt_opts *opts = mnt_opts; |
026eb167 | 2681 | struct superblock_security_struct *sbsec = sb->s_security; |
bd323655 AV |
2682 | u32 sid; |
2683 | int rc; | |
026eb167 EP |
2684 | |
2685 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2686 | return 0; | |
2687 | ||
204cc0cc | 2688 | if (!opts) |
026eb167 EP |
2689 | return 0; |
2690 | ||
bd323655 AV |
2691 | if (opts->fscontext) { |
2692 | rc = parse_sid(sb, opts->fscontext, &sid); | |
2693 | if (rc) | |
c039bc3c | 2694 | return rc; |
bd323655 AV |
2695 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) |
2696 | goto out_bad_option; | |
026eb167 | 2697 | } |
bd323655 AV |
2698 | if (opts->context) { |
2699 | rc = parse_sid(sb, opts->context, &sid); | |
2700 | if (rc) | |
2701 | return rc; | |
2702 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2703 | goto out_bad_option; | |
2704 | } | |
2705 | if (opts->rootcontext) { | |
2706 | struct inode_security_struct *root_isec; | |
2707 | root_isec = backing_inode_security(sb->s_root); | |
2708 | rc = parse_sid(sb, opts->rootcontext, &sid); | |
2709 | if (rc) | |
2710 | return rc; | |
2711 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2712 | goto out_bad_option; | |
2713 | } | |
2714 | if (opts->defcontext) { | |
2715 | rc = parse_sid(sb, opts->defcontext, &sid); | |
2716 | if (rc) | |
2717 | return rc; | |
2718 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2719 | goto out_bad_option; | |
026eb167 | 2720 | } |
c039bc3c | 2721 | return 0; |
026eb167 | 2722 | |
026eb167 | 2723 | out_bad_option: |
c103a91e | 2724 | pr_warn("SELinux: unable to change security options " |
29b1deb2 LT |
2725 | "during remount (dev %s, type=%s)\n", sb->s_id, |
2726 | sb->s_type->name); | |
c039bc3c | 2727 | return -EINVAL; |
026eb167 EP |
2728 | } |
2729 | ||
a10d7c22 | 2730 | static int selinux_sb_kern_mount(struct super_block *sb) |
1da177e4 | 2731 | { |
88e67f3b | 2732 | const struct cred *cred = current_cred(); |
2bf49690 | 2733 | struct common_audit_data ad; |
74192246 | 2734 | |
50c205f5 | 2735 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2736 | ad.u.dentry = sb->s_root; |
88e67f3b | 2737 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2738 | } |
2739 | ||
726c3342 | 2740 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2741 | { |
88e67f3b | 2742 | const struct cred *cred = current_cred(); |
2bf49690 | 2743 | struct common_audit_data ad; |
1da177e4 | 2744 | |
50c205f5 | 2745 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2746 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2747 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2748 | } |
2749 | ||
808d4e3c | 2750 | static int selinux_mount(const char *dev_name, |
8a04c43b | 2751 | const struct path *path, |
808d4e3c | 2752 | const char *type, |
828dfe1d EP |
2753 | unsigned long flags, |
2754 | void *data) | |
1da177e4 | 2755 | { |
88e67f3b | 2756 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2757 | |
2758 | if (flags & MS_REMOUNT) | |
d8c9584e | 2759 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2760 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2761 | else |
2875fa00 | 2762 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2763 | } |
2764 | ||
2765 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2766 | { | |
88e67f3b | 2767 | const struct cred *cred = current_cred(); |
1da177e4 | 2768 | |
88e67f3b | 2769 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2770 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2771 | } |
2772 | ||
0b52075e AV |
2773 | static int selinux_fs_context_dup(struct fs_context *fc, |
2774 | struct fs_context *src_fc) | |
2775 | { | |
2776 | const struct selinux_mnt_opts *src = src_fc->security; | |
2777 | struct selinux_mnt_opts *opts; | |
2778 | ||
2779 | if (!src) | |
2780 | return 0; | |
2781 | ||
2782 | fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); | |
2783 | if (!fc->security) | |
2784 | return -ENOMEM; | |
2785 | ||
2786 | opts = fc->security; | |
2787 | ||
2788 | if (src->fscontext) { | |
2789 | opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL); | |
2790 | if (!opts->fscontext) | |
2791 | return -ENOMEM; | |
2792 | } | |
2793 | if (src->context) { | |
2794 | opts->context = kstrdup(src->context, GFP_KERNEL); | |
2795 | if (!opts->context) | |
2796 | return -ENOMEM; | |
2797 | } | |
2798 | if (src->rootcontext) { | |
2799 | opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL); | |
2800 | if (!opts->rootcontext) | |
2801 | return -ENOMEM; | |
2802 | } | |
2803 | if (src->defcontext) { | |
2804 | opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL); | |
2805 | if (!opts->defcontext) | |
2806 | return -ENOMEM; | |
2807 | } | |
2808 | return 0; | |
2809 | } | |
2810 | ||
442155c1 DH |
2811 | static const struct fs_parameter_spec selinux_param_specs[] = { |
2812 | fsparam_string(CONTEXT_STR, Opt_context), | |
2813 | fsparam_string(DEFCONTEXT_STR, Opt_defcontext), | |
2814 | fsparam_string(FSCONTEXT_STR, Opt_fscontext), | |
2815 | fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), | |
2816 | fsparam_flag (SECLABEL_STR, Opt_seclabel), | |
2817 | {} | |
2818 | }; | |
2819 | ||
2820 | static const struct fs_parameter_description selinux_fs_parameters = { | |
2821 | .name = "SELinux", | |
2822 | .specs = selinux_param_specs, | |
2823 | }; | |
2824 | ||
2825 | static int selinux_fs_context_parse_param(struct fs_context *fc, | |
2826 | struct fs_parameter *param) | |
2827 | { | |
2828 | struct fs_parse_result result; | |
2829 | int opt, rc; | |
2830 | ||
2831 | opt = fs_parse(fc, &selinux_fs_parameters, param, &result); | |
2832 | if (opt < 0) | |
2833 | return opt; | |
2834 | ||
2835 | rc = selinux_add_opt(opt, param->string, &fc->security); | |
2836 | if (!rc) { | |
2837 | param->string = NULL; | |
2838 | rc = 1; | |
2839 | } | |
2840 | return rc; | |
2841 | } | |
2842 | ||
1da177e4 LT |
2843 | /* inode security operations */ |
2844 | ||
2845 | static int selinux_inode_alloc_security(struct inode *inode) | |
2846 | { | |
2847 | return inode_alloc_security(inode); | |
2848 | } | |
2849 | ||
2850 | static void selinux_inode_free_security(struct inode *inode) | |
2851 | { | |
2852 | inode_free_security(inode); | |
2853 | } | |
2854 | ||
d47be3df | 2855 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
4f3ccd76 | 2856 | const struct qstr *name, void **ctx, |
d47be3df DQ |
2857 | u32 *ctxlen) |
2858 | { | |
d47be3df DQ |
2859 | u32 newsid; |
2860 | int rc; | |
2861 | ||
0c6cfa62 | 2862 | rc = selinux_determine_inode_label(selinux_cred(current_cred()), |
c957f6df | 2863 | d_inode(dentry->d_parent), name, |
c3c188b2 DH |
2864 | inode_mode_to_security_class(mode), |
2865 | &newsid); | |
2866 | if (rc) | |
2867 | return rc; | |
d47be3df | 2868 | |
aa8e712c SS |
2869 | return security_sid_to_context(&selinux_state, newsid, (char **)ctx, |
2870 | ctxlen); | |
d47be3df DQ |
2871 | } |
2872 | ||
a518b0a5 VG |
2873 | static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, |
2874 | struct qstr *name, | |
2875 | const struct cred *old, | |
2876 | struct cred *new) | |
2877 | { | |
2878 | u32 newsid; | |
2879 | int rc; | |
2880 | struct task_security_struct *tsec; | |
2881 | ||
0c6cfa62 | 2882 | rc = selinux_determine_inode_label(selinux_cred(old), |
a518b0a5 VG |
2883 | d_inode(dentry->d_parent), name, |
2884 | inode_mode_to_security_class(mode), | |
2885 | &newsid); | |
2886 | if (rc) | |
2887 | return rc; | |
2888 | ||
0c6cfa62 | 2889 | tsec = selinux_cred(new); |
a518b0a5 VG |
2890 | tsec->create_sid = newsid; |
2891 | return 0; | |
2892 | } | |
2893 | ||
5e41ff9e | 2894 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
2895 | const struct qstr *qstr, |
2896 | const char **name, | |
2a7dba39 | 2897 | void **value, size_t *len) |
5e41ff9e | 2898 | { |
0c6cfa62 | 2899 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
5e41ff9e | 2900 | struct superblock_security_struct *sbsec; |
c0d4f464 | 2901 | u32 newsid, clen; |
5e41ff9e | 2902 | int rc; |
9548906b | 2903 | char *context; |
5e41ff9e | 2904 | |
5e41ff9e | 2905 | sbsec = dir->i_sb->s_security; |
5e41ff9e | 2906 | |
275bb41e DH |
2907 | newsid = tsec->create_sid; |
2908 | ||
0c6cfa62 | 2909 | rc = selinux_determine_inode_label(selinux_cred(current_cred()), |
c3c188b2 DH |
2910 | dir, qstr, |
2911 | inode_mode_to_security_class(inode->i_mode), | |
2912 | &newsid); | |
2913 | if (rc) | |
2914 | return rc; | |
5e41ff9e | 2915 | |
296fddf7 | 2916 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 2917 | if (sbsec->flags & SE_SBINITIALIZED) { |
80788c22 | 2918 | struct inode_security_struct *isec = selinux_inode(inode); |
296fddf7 EP |
2919 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
2920 | isec->sid = newsid; | |
6f3be9f5 | 2921 | isec->initialized = LABEL_INITIALIZED; |
296fddf7 | 2922 | } |
5e41ff9e | 2923 | |
aa8e712c | 2924 | if (!selinux_state.initialized || !(sbsec->flags & SBLABEL_MNT)) |
25a74f3b SS |
2925 | return -EOPNOTSUPP; |
2926 | ||
9548906b TH |
2927 | if (name) |
2928 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 2929 | |
570bc1c2 | 2930 | if (value && len) { |
aa8e712c SS |
2931 | rc = security_sid_to_context_force(&selinux_state, newsid, |
2932 | &context, &clen); | |
9548906b | 2933 | if (rc) |
570bc1c2 | 2934 | return rc; |
570bc1c2 SS |
2935 | *value = context; |
2936 | *len = clen; | |
5e41ff9e | 2937 | } |
5e41ff9e | 2938 | |
5e41ff9e SS |
2939 | return 0; |
2940 | } | |
2941 | ||
4acdaf27 | 2942 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
2943 | { |
2944 | return may_create(dir, dentry, SECCLASS_FILE); | |
2945 | } | |
2946 | ||
1da177e4 LT |
2947 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2948 | { | |
1da177e4 LT |
2949 | return may_link(dir, old_dentry, MAY_LINK); |
2950 | } | |
2951 | ||
1da177e4 LT |
2952 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2953 | { | |
1da177e4 LT |
2954 | return may_link(dir, dentry, MAY_UNLINK); |
2955 | } | |
2956 | ||
2957 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2958 | { | |
2959 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2960 | } | |
2961 | ||
18bb1db3 | 2962 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
2963 | { |
2964 | return may_create(dir, dentry, SECCLASS_DIR); | |
2965 | } | |
2966 | ||
1da177e4 LT |
2967 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2968 | { | |
2969 | return may_link(dir, dentry, MAY_RMDIR); | |
2970 | } | |
2971 | ||
1a67aafb | 2972 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 2973 | { |
1da177e4 LT |
2974 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
2975 | } | |
2976 | ||
1da177e4 | 2977 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 2978 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
2979 | { |
2980 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2981 | } | |
2982 | ||
1da177e4 LT |
2983 | static int selinux_inode_readlink(struct dentry *dentry) |
2984 | { | |
88e67f3b DH |
2985 | const struct cred *cred = current_cred(); |
2986 | ||
2875fa00 | 2987 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
2988 | } |
2989 | ||
bda0be7a N |
2990 | static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, |
2991 | bool rcu) | |
1da177e4 | 2992 | { |
88e67f3b | 2993 | const struct cred *cred = current_cred(); |
bda0be7a N |
2994 | struct common_audit_data ad; |
2995 | struct inode_security_struct *isec; | |
2996 | u32 sid; | |
1da177e4 | 2997 | |
bda0be7a N |
2998 | validate_creds(cred); |
2999 | ||
3000 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
3001 | ad.u.dentry = dentry; | |
3002 | sid = cred_sid(cred); | |
5d226df4 AG |
3003 | isec = inode_security_rcu(inode, rcu); |
3004 | if (IS_ERR(isec)) | |
3005 | return PTR_ERR(isec); | |
bda0be7a | 3006 | |
e46e01ee SS |
3007 | return avc_has_perm(&selinux_state, |
3008 | sid, isec->sid, isec->sclass, FILE__READ, &ad); | |
1da177e4 LT |
3009 | } |
3010 | ||
d4cf970d EP |
3011 | static noinline int audit_inode_permission(struct inode *inode, |
3012 | u32 perms, u32 audited, u32 denied, | |
626b9740 | 3013 | int result, |
d4cf970d | 3014 | unsigned flags) |
1da177e4 | 3015 | { |
b782e0a6 | 3016 | struct common_audit_data ad; |
80788c22 | 3017 | struct inode_security_struct *isec = selinux_inode(inode); |
d4cf970d EP |
3018 | int rc; |
3019 | ||
50c205f5 | 3020 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
3021 | ad.u.inode = inode; |
3022 | ||
6b6bc620 SS |
3023 | rc = slow_avc_audit(&selinux_state, |
3024 | current_sid(), isec->sid, isec->sclass, perms, | |
626b9740 | 3025 | audited, denied, result, &ad, flags); |
d4cf970d EP |
3026 | if (rc) |
3027 | return rc; | |
3028 | return 0; | |
3029 | } | |
3030 | ||
e74f71eb | 3031 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 3032 | { |
88e67f3b | 3033 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
3034 | u32 perms; |
3035 | bool from_access; | |
cf1dd1da | 3036 | unsigned flags = mask & MAY_NOT_BLOCK; |
2e334057 EP |
3037 | struct inode_security_struct *isec; |
3038 | u32 sid; | |
3039 | struct av_decision avd; | |
3040 | int rc, rc2; | |
3041 | u32 audited, denied; | |
1da177e4 | 3042 | |
b782e0a6 | 3043 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
3044 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
3045 | ||
b782e0a6 EP |
3046 | /* No permission to check. Existence test. */ |
3047 | if (!mask) | |
1da177e4 | 3048 | return 0; |
1da177e4 | 3049 | |
2e334057 | 3050 | validate_creds(cred); |
b782e0a6 | 3051 | |
2e334057 EP |
3052 | if (unlikely(IS_PRIVATE(inode))) |
3053 | return 0; | |
b782e0a6 EP |
3054 | |
3055 | perms = file_mask_to_av(inode->i_mode, mask); | |
3056 | ||
2e334057 | 3057 | sid = cred_sid(cred); |
5d226df4 AG |
3058 | isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK); |
3059 | if (IS_ERR(isec)) | |
3060 | return PTR_ERR(isec); | |
2e334057 | 3061 | |
6b6bc620 | 3062 | rc = avc_has_perm_noaudit(&selinux_state, |
3a28cff3 SS |
3063 | sid, isec->sid, isec->sclass, perms, |
3064 | (flags & MAY_NOT_BLOCK) ? AVC_NONBLOCKING : 0, | |
3065 | &avd); | |
2e334057 EP |
3066 | audited = avc_audit_required(perms, &avd, rc, |
3067 | from_access ? FILE__AUDIT_ACCESS : 0, | |
3068 | &denied); | |
3069 | if (likely(!audited)) | |
3070 | return rc; | |
3071 | ||
626b9740 | 3072 | rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags); |
2e334057 EP |
3073 | if (rc2) |
3074 | return rc2; | |
3075 | return rc; | |
1da177e4 LT |
3076 | } |
3077 | ||
3078 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
3079 | { | |
88e67f3b | 3080 | const struct cred *cred = current_cred(); |
ccb54478 | 3081 | struct inode *inode = d_backing_inode(dentry); |
bc6a6008 | 3082 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 3083 | __u32 av = FILE__WRITE; |
1da177e4 | 3084 | |
bc6a6008 AW |
3085 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
3086 | if (ia_valid & ATTR_FORCE) { | |
3087 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
3088 | ATTR_FORCE); | |
3089 | if (!ia_valid) | |
3090 | return 0; | |
3091 | } | |
1da177e4 | 3092 | |
bc6a6008 AW |
3093 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
3094 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 3095 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 3096 | |
aa8e712c | 3097 | if (selinux_policycap_openperm() && |
ccb54478 SS |
3098 | inode->i_sb->s_magic != SOCKFS_MAGIC && |
3099 | (ia_valid & ATTR_SIZE) && | |
3100 | !(ia_valid & ATTR_FILE)) | |
95dbf739 EP |
3101 | av |= FILE__OPEN; |
3102 | ||
3103 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
3104 | } |
3105 | ||
3f7036a0 | 3106 | static int selinux_inode_getattr(const struct path *path) |
1da177e4 | 3107 | { |
3f7036a0 | 3108 | return path_has_perm(current_cred(), path, FILE__GETATTR); |
1da177e4 LT |
3109 | } |
3110 | ||
db59000a SS |
3111 | static bool has_cap_mac_admin(bool audit) |
3112 | { | |
3113 | const struct cred *cred = current_cred(); | |
c1a85a00 | 3114 | unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; |
db59000a | 3115 | |
c1a85a00 | 3116 | if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) |
db59000a | 3117 | return false; |
c1a85a00 | 3118 | if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) |
db59000a SS |
3119 | return false; |
3120 | return true; | |
3121 | } | |
3122 | ||
8f0cfa52 DH |
3123 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
3124 | const void *value, size_t size, int flags) | |
1da177e4 | 3125 | { |
c6f493d6 | 3126 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3127 | struct inode_security_struct *isec; |
1da177e4 | 3128 | struct superblock_security_struct *sbsec; |
2bf49690 | 3129 | struct common_audit_data ad; |
275bb41e | 3130 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
3131 | int rc = 0; |
3132 | ||
6b240306 EB |
3133 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3134 | rc = cap_inode_setxattr(dentry, name, value, size, flags); | |
3135 | if (rc) | |
3136 | return rc; | |
3137 | ||
3138 | /* Not an attribute we recognize, so just check the | |
3139 | ordinary setattr permission. */ | |
3140 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3141 | } | |
1da177e4 | 3142 | |
3e3e24b4 JL |
3143 | if (!selinux_state.initialized) |
3144 | return (inode_owner_or_capable(inode) ? 0 : -EPERM); | |
3145 | ||
1da177e4 | 3146 | sbsec = inode->i_sb->s_security; |
12f348b9 | 3147 | if (!(sbsec->flags & SBLABEL_MNT)) |
1da177e4 LT |
3148 | return -EOPNOTSUPP; |
3149 | ||
2e149670 | 3150 | if (!inode_owner_or_capable(inode)) |
1da177e4 LT |
3151 | return -EPERM; |
3152 | ||
50c205f5 | 3153 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 3154 | ad.u.dentry = dentry; |
1da177e4 | 3155 | |
20cdef8d | 3156 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
3157 | rc = avc_has_perm(&selinux_state, |
3158 | sid, isec->sid, isec->sclass, | |
1da177e4 LT |
3159 | FILE__RELABELFROM, &ad); |
3160 | if (rc) | |
3161 | return rc; | |
3162 | ||
aa8e712c SS |
3163 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3164 | GFP_KERNEL); | |
12b29f34 | 3165 | if (rc == -EINVAL) { |
db59000a | 3166 | if (!has_cap_mac_admin(true)) { |
d6ea83ec EP |
3167 | struct audit_buffer *ab; |
3168 | size_t audit_size; | |
d6ea83ec EP |
3169 | |
3170 | /* We strip a nul only if it is at the end, otherwise the | |
3171 | * context contains a nul and we should audit that */ | |
e3fea3f7 | 3172 | if (value) { |
add24372 CIK |
3173 | const char *str = value; |
3174 | ||
e3fea3f7 AV |
3175 | if (str[size - 1] == '\0') |
3176 | audit_size = size - 1; | |
3177 | else | |
3178 | audit_size = size; | |
3179 | } else { | |
e3fea3f7 AV |
3180 | audit_size = 0; |
3181 | } | |
cdfb6b34 RGB |
3182 | ab = audit_log_start(audit_context(), |
3183 | GFP_ATOMIC, AUDIT_SELINUX_ERR); | |
d6ea83ec EP |
3184 | audit_log_format(ab, "op=setxattr invalid_context="); |
3185 | audit_log_n_untrustedstring(ab, value, audit_size); | |
3186 | audit_log_end(ab); | |
3187 | ||
12b29f34 | 3188 | return rc; |
d6ea83ec | 3189 | } |
aa8e712c SS |
3190 | rc = security_context_to_sid_force(&selinux_state, value, |
3191 | size, &newsid); | |
12b29f34 | 3192 | } |
1da177e4 LT |
3193 | if (rc) |
3194 | return rc; | |
3195 | ||
6b6bc620 SS |
3196 | rc = avc_has_perm(&selinux_state, |
3197 | sid, newsid, isec->sclass, | |
1da177e4 LT |
3198 | FILE__RELABELTO, &ad); |
3199 | if (rc) | |
3200 | return rc; | |
3201 | ||
aa8e712c SS |
3202 | rc = security_validate_transition(&selinux_state, isec->sid, newsid, |
3203 | sid, isec->sclass); | |
1da177e4 LT |
3204 | if (rc) |
3205 | return rc; | |
3206 | ||
6b6bc620 SS |
3207 | return avc_has_perm(&selinux_state, |
3208 | newsid, | |
1da177e4 LT |
3209 | sbsec->sid, |
3210 | SECCLASS_FILESYSTEM, | |
3211 | FILESYSTEM__ASSOCIATE, | |
3212 | &ad); | |
3213 | } | |
3214 | ||
8f0cfa52 | 3215 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 3216 | const void *value, size_t size, |
8f0cfa52 | 3217 | int flags) |
1da177e4 | 3218 | { |
c6f493d6 | 3219 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3220 | struct inode_security_struct *isec; |
1da177e4 LT |
3221 | u32 newsid; |
3222 | int rc; | |
3223 | ||
3224 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
3225 | /* Not an attribute we recognize, so nothing to do. */ | |
3226 | return; | |
3227 | } | |
3228 | ||
3e3e24b4 JL |
3229 | if (!selinux_state.initialized) { |
3230 | /* If we haven't even been initialized, then we can't validate | |
3231 | * against a policy, so leave the label as invalid. It may | |
3232 | * resolve to a valid label on the next revalidation try if | |
3233 | * we've since initialized. | |
3234 | */ | |
3235 | return; | |
3236 | } | |
3237 | ||
aa8e712c SS |
3238 | rc = security_context_to_sid_force(&selinux_state, value, size, |
3239 | &newsid); | |
1da177e4 | 3240 | if (rc) { |
c103a91e | 3241 | pr_err("SELinux: unable to map context to SID" |
12b29f34 SS |
3242 | "for (%s, %lu), rc=%d\n", |
3243 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
3244 | return; |
3245 | } | |
3246 | ||
20cdef8d | 3247 | isec = backing_inode_security(dentry); |
9287aed2 | 3248 | spin_lock(&isec->lock); |
aa9c2669 | 3249 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3250 | isec->sid = newsid; |
6f3be9f5 | 3251 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3252 | spin_unlock(&isec->lock); |
aa9c2669 | 3253 | |
1da177e4 LT |
3254 | return; |
3255 | } | |
3256 | ||
8f0cfa52 | 3257 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 3258 | { |
88e67f3b DH |
3259 | const struct cred *cred = current_cred(); |
3260 | ||
2875fa00 | 3261 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3262 | } |
3263 | ||
828dfe1d | 3264 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 3265 | { |
88e67f3b DH |
3266 | const struct cred *cred = current_cred(); |
3267 | ||
2875fa00 | 3268 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3269 | } |
3270 | ||
8f0cfa52 | 3271 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 3272 | { |
6b240306 EB |
3273 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3274 | int rc = cap_inode_removexattr(dentry, name); | |
3275 | if (rc) | |
3276 | return rc; | |
3277 | ||
3278 | /* Not an attribute we recognize, so just check the | |
3279 | ordinary setattr permission. */ | |
3280 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3281 | } | |
1da177e4 LT |
3282 | |
3283 | /* No one is allowed to remove a SELinux security label. | |
3284 | You can change the label, but all data must be labeled. */ | |
3285 | return -EACCES; | |
3286 | } | |
3287 | ||
ac5656d8 AG |
3288 | static int selinux_path_notify(const struct path *path, u64 mask, |
3289 | unsigned int obj_type) | |
3290 | { | |
3291 | int ret; | |
3292 | u32 perm; | |
3293 | ||
3294 | struct common_audit_data ad; | |
3295 | ||
3296 | ad.type = LSM_AUDIT_DATA_PATH; | |
3297 | ad.u.path = *path; | |
3298 | ||
3299 | /* | |
3300 | * Set permission needed based on the type of mark being set. | |
3301 | * Performs an additional check for sb watches. | |
3302 | */ | |
3303 | switch (obj_type) { | |
3304 | case FSNOTIFY_OBJ_TYPE_VFSMOUNT: | |
3305 | perm = FILE__WATCH_MOUNT; | |
3306 | break; | |
3307 | case FSNOTIFY_OBJ_TYPE_SB: | |
3308 | perm = FILE__WATCH_SB; | |
3309 | ret = superblock_has_perm(current_cred(), path->dentry->d_sb, | |
3310 | FILESYSTEM__WATCH, &ad); | |
3311 | if (ret) | |
3312 | return ret; | |
3313 | break; | |
3314 | case FSNOTIFY_OBJ_TYPE_INODE: | |
3315 | perm = FILE__WATCH; | |
3316 | break; | |
3317 | default: | |
3318 | return -EINVAL; | |
3319 | } | |
3320 | ||
3321 | /* blocking watches require the file:watch_with_perm permission */ | |
3322 | if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) | |
3323 | perm |= FILE__WATCH_WITH_PERM; | |
3324 | ||
3325 | /* watches on read-like events need the file:watch_reads permission */ | |
3326 | if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) | |
3327 | perm |= FILE__WATCH_READS; | |
3328 | ||
3329 | return path_has_perm(current_cred(), path, perm); | |
3330 | } | |
3331 | ||
d381d8a9 | 3332 | /* |
abc69bb6 | 3333 | * Copy the inode security context value to the user. |
d381d8a9 JM |
3334 | * |
3335 | * Permission check is handled by selinux_inode_getxattr hook. | |
3336 | */ | |
ea861dfd | 3337 | static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 3338 | { |
42492594 DQ |
3339 | u32 size; |
3340 | int error; | |
3341 | char *context = NULL; | |
20cdef8d | 3342 | struct inode_security_struct *isec; |
d381d8a9 | 3343 | |
8c8570fb DK |
3344 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
3345 | return -EOPNOTSUPP; | |
d381d8a9 | 3346 | |
abc69bb6 SS |
3347 | /* |
3348 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3349 | * value even if it is not defined by current policy; otherwise, | |
3350 | * use the in-core value under current policy. | |
3351 | * Use the non-auditing forms of the permission checks since | |
3352 | * getxattr may be called by unprivileged processes commonly | |
3353 | * and lack of permission just means that we fall back to the | |
3354 | * in-core context value, not a denial. | |
3355 | */ | |
20cdef8d | 3356 | isec = inode_security(inode); |
db59000a | 3357 | if (has_cap_mac_admin(false)) |
aa8e712c SS |
3358 | error = security_sid_to_context_force(&selinux_state, |
3359 | isec->sid, &context, | |
abc69bb6 SS |
3360 | &size); |
3361 | else | |
aa8e712c SS |
3362 | error = security_sid_to_context(&selinux_state, isec->sid, |
3363 | &context, &size); | |
42492594 DQ |
3364 | if (error) |
3365 | return error; | |
3366 | error = size; | |
3367 | if (alloc) { | |
3368 | *buffer = context; | |
3369 | goto out_nofree; | |
3370 | } | |
3371 | kfree(context); | |
3372 | out_nofree: | |
3373 | return error; | |
1da177e4 LT |
3374 | } |
3375 | ||
3376 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 3377 | const void *value, size_t size, int flags) |
1da177e4 | 3378 | { |
2c97165b | 3379 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
53e0c2aa | 3380 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; |
1da177e4 LT |
3381 | u32 newsid; |
3382 | int rc; | |
3383 | ||
3384 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3385 | return -EOPNOTSUPP; | |
3386 | ||
53e0c2aa OM |
3387 | if (!(sbsec->flags & SBLABEL_MNT)) |
3388 | return -EOPNOTSUPP; | |
3389 | ||
1da177e4 LT |
3390 | if (!value || !size) |
3391 | return -EACCES; | |
3392 | ||
aa8e712c SS |
3393 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3394 | GFP_KERNEL); | |
1da177e4 LT |
3395 | if (rc) |
3396 | return rc; | |
3397 | ||
9287aed2 | 3398 | spin_lock(&isec->lock); |
aa9c2669 | 3399 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3400 | isec->sid = newsid; |
6f3be9f5 | 3401 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3402 | spin_unlock(&isec->lock); |
1da177e4 LT |
3403 | return 0; |
3404 | } | |
3405 | ||
3406 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3407 | { | |
3408 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3409 | if (buffer && len <= buffer_size) | |
3410 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3411 | return len; | |
3412 | } | |
3413 | ||
d6335d77 | 3414 | static void selinux_inode_getsecid(struct inode *inode, u32 *secid) |
713a04ae | 3415 | { |
e817c2f3 | 3416 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
713a04ae AD |
3417 | *secid = isec->sid; |
3418 | } | |
3419 | ||
56909eb3 VG |
3420 | static int selinux_inode_copy_up(struct dentry *src, struct cred **new) |
3421 | { | |
3422 | u32 sid; | |
3423 | struct task_security_struct *tsec; | |
3424 | struct cred *new_creds = *new; | |
3425 | ||
3426 | if (new_creds == NULL) { | |
3427 | new_creds = prepare_creds(); | |
3428 | if (!new_creds) | |
3429 | return -ENOMEM; | |
3430 | } | |
3431 | ||
0c6cfa62 | 3432 | tsec = selinux_cred(new_creds); |
56909eb3 VG |
3433 | /* Get label from overlay inode and set it in create_sid */ |
3434 | selinux_inode_getsecid(d_inode(src), &sid); | |
3435 | tsec->create_sid = sid; | |
3436 | *new = new_creds; | |
3437 | return 0; | |
3438 | } | |
3439 | ||
19472b69 VG |
3440 | static int selinux_inode_copy_up_xattr(const char *name) |
3441 | { | |
3442 | /* The copy_up hook above sets the initial context on an inode, but we | |
3443 | * don't then want to overwrite it by blindly copying all the lower | |
3444 | * xattrs up. Instead, we have to filter out SELinux-related xattrs. | |
3445 | */ | |
3446 | if (strcmp(name, XATTR_NAME_SELINUX) == 0) | |
3447 | return 1; /* Discard */ | |
3448 | /* | |
3449 | * Any other attribute apart from SELINUX is not claimed, supported | |
3450 | * by selinux. | |
3451 | */ | |
3452 | return -EOPNOTSUPP; | |
3453 | } | |
3454 | ||
ec882da5 OM |
3455 | /* kernfs node operations */ |
3456 | ||
c72c4cde Y |
3457 | static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, |
3458 | struct kernfs_node *kn) | |
ec882da5 | 3459 | { |
169ce0c0 | 3460 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
ec882da5 OM |
3461 | u32 parent_sid, newsid, clen; |
3462 | int rc; | |
3463 | char *context; | |
3464 | ||
1537ad15 | 3465 | rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); |
ec882da5 OM |
3466 | if (rc == -ENODATA) |
3467 | return 0; | |
3468 | else if (rc < 0) | |
3469 | return rc; | |
3470 | ||
3471 | clen = (u32)rc; | |
3472 | context = kmalloc(clen, GFP_KERNEL); | |
3473 | if (!context) | |
3474 | return -ENOMEM; | |
3475 | ||
1537ad15 | 3476 | rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); |
ec882da5 OM |
3477 | if (rc < 0) { |
3478 | kfree(context); | |
3479 | return rc; | |
3480 | } | |
3481 | ||
3482 | rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid, | |
3483 | GFP_KERNEL); | |
3484 | kfree(context); | |
3485 | if (rc) | |
3486 | return rc; | |
3487 | ||
3488 | if (tsec->create_sid) { | |
3489 | newsid = tsec->create_sid; | |
3490 | } else { | |
3491 | u16 secclass = inode_mode_to_security_class(kn->mode); | |
3492 | struct qstr q; | |
3493 | ||
3494 | q.name = kn->name; | |
3495 | q.hash_len = hashlen_string(kn_dir, kn->name); | |
3496 | ||
3497 | rc = security_transition_sid(&selinux_state, tsec->sid, | |
3498 | parent_sid, secclass, &q, | |
3499 | &newsid); | |
3500 | if (rc) | |
3501 | return rc; | |
3502 | } | |
3503 | ||
3504 | rc = security_sid_to_context_force(&selinux_state, newsid, | |
3505 | &context, &clen); | |
3506 | if (rc) | |
3507 | return rc; | |
3508 | ||
1537ad15 OM |
3509 | rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, |
3510 | XATTR_CREATE); | |
ec882da5 OM |
3511 | kfree(context); |
3512 | return rc; | |
3513 | } | |
3514 | ||
3515 | ||
1da177e4 LT |
3516 | /* file security operations */ |
3517 | ||
788e7dd4 | 3518 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3519 | { |
88e67f3b | 3520 | const struct cred *cred = current_cred(); |
496ad9aa | 3521 | struct inode *inode = file_inode(file); |
1da177e4 | 3522 | |
1da177e4 LT |
3523 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3524 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3525 | mask |= MAY_APPEND; | |
3526 | ||
389fb800 PM |
3527 | return file_has_perm(cred, file, |
3528 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3529 | } |
3530 | ||
788e7dd4 YN |
3531 | static int selinux_file_permission(struct file *file, int mask) |
3532 | { | |
496ad9aa | 3533 | struct inode *inode = file_inode(file); |
bb6c6b02 | 3534 | struct file_security_struct *fsec = selinux_file(file); |
b197367e | 3535 | struct inode_security_struct *isec; |
20dda18b SS |
3536 | u32 sid = current_sid(); |
3537 | ||
389fb800 | 3538 | if (!mask) |
788e7dd4 YN |
3539 | /* No permission to check. Existence test. */ |
3540 | return 0; | |
788e7dd4 | 3541 | |
b197367e | 3542 | isec = inode_security(inode); |
20dda18b | 3543 | if (sid == fsec->sid && fsec->isid == isec->sid && |
6b6bc620 | 3544 | fsec->pseqno == avc_policy_seqno(&selinux_state)) |
83d49856 | 3545 | /* No change since file_open check. */ |
20dda18b SS |
3546 | return 0; |
3547 | ||
788e7dd4 YN |
3548 | return selinux_revalidate_file_permission(file, mask); |
3549 | } | |
3550 | ||
1da177e4 LT |
3551 | static int selinux_file_alloc_security(struct file *file) |
3552 | { | |
3553 | return file_alloc_security(file); | |
3554 | } | |
3555 | ||
fa1aa143 JVS |
3556 | /* |
3557 | * Check whether a task has the ioctl permission and cmd | |
3558 | * operation to an inode. | |
3559 | */ | |
1d2a168a | 3560 | static int ioctl_has_perm(const struct cred *cred, struct file *file, |
fa1aa143 JVS |
3561 | u32 requested, u16 cmd) |
3562 | { | |
3563 | struct common_audit_data ad; | |
bb6c6b02 | 3564 | struct file_security_struct *fsec = selinux_file(file); |
fa1aa143 | 3565 | struct inode *inode = file_inode(file); |
20cdef8d | 3566 | struct inode_security_struct *isec; |
fa1aa143 JVS |
3567 | struct lsm_ioctlop_audit ioctl; |
3568 | u32 ssid = cred_sid(cred); | |
3569 | int rc; | |
3570 | u8 driver = cmd >> 8; | |
3571 | u8 xperm = cmd & 0xff; | |
3572 | ||
3573 | ad.type = LSM_AUDIT_DATA_IOCTL_OP; | |
3574 | ad.u.op = &ioctl; | |
3575 | ad.u.op->cmd = cmd; | |
3576 | ad.u.op->path = file->f_path; | |
3577 | ||
3578 | if (ssid != fsec->sid) { | |
6b6bc620 SS |
3579 | rc = avc_has_perm(&selinux_state, |
3580 | ssid, fsec->sid, | |
fa1aa143 JVS |
3581 | SECCLASS_FD, |
3582 | FD__USE, | |
3583 | &ad); | |
3584 | if (rc) | |
3585 | goto out; | |
3586 | } | |
3587 | ||
3588 | if (unlikely(IS_PRIVATE(inode))) | |
3589 | return 0; | |
3590 | ||
20cdef8d | 3591 | isec = inode_security(inode); |
6b6bc620 SS |
3592 | rc = avc_has_extended_perms(&selinux_state, |
3593 | ssid, isec->sid, isec->sclass, | |
3594 | requested, driver, xperm, &ad); | |
fa1aa143 JVS |
3595 | out: |
3596 | return rc; | |
3597 | } | |
3598 | ||
1da177e4 LT |
3599 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
3600 | unsigned long arg) | |
3601 | { | |
88e67f3b | 3602 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3603 | int error = 0; |
1da177e4 | 3604 | |
0b24dcb7 EP |
3605 | switch (cmd) { |
3606 | case FIONREAD: | |
3607 | /* fall through */ | |
3608 | case FIBMAP: | |
3609 | /* fall through */ | |
3610 | case FIGETBSZ: | |
3611 | /* fall through */ | |
2f99c369 | 3612 | case FS_IOC_GETFLAGS: |
0b24dcb7 | 3613 | /* fall through */ |
2f99c369 | 3614 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3615 | error = file_has_perm(cred, file, FILE__GETATTR); |
3616 | break; | |
1da177e4 | 3617 | |
2f99c369 | 3618 | case FS_IOC_SETFLAGS: |
0b24dcb7 | 3619 | /* fall through */ |
2f99c369 | 3620 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3621 | error = file_has_perm(cred, file, FILE__SETATTR); |
3622 | break; | |
3623 | ||
3624 | /* sys_ioctl() checks */ | |
3625 | case FIONBIO: | |
3626 | /* fall through */ | |
3627 | case FIOASYNC: | |
3628 | error = file_has_perm(cred, file, 0); | |
3629 | break; | |
1da177e4 | 3630 | |
0b24dcb7 EP |
3631 | case KDSKBENT: |
3632 | case KDSKBSENT: | |
6a9de491 | 3633 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
c1a85a00 | 3634 | CAP_OPT_NONE, true); |
0b24dcb7 EP |
3635 | break; |
3636 | ||
3637 | /* default case assumes that the command will go | |
3638 | * to the file's ioctl() function. | |
3639 | */ | |
3640 | default: | |
fa1aa143 | 3641 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
0b24dcb7 EP |
3642 | } |
3643 | return error; | |
1da177e4 LT |
3644 | } |
3645 | ||
fcaaade1 SS |
3646 | static int default_noexec; |
3647 | ||
1da177e4 LT |
3648 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3649 | { | |
88e67f3b | 3650 | const struct cred *cred = current_cred(); |
be0554c9 | 3651 | u32 sid = cred_sid(cred); |
d84f4f99 | 3652 | int rc = 0; |
88e67f3b | 3653 | |
fcaaade1 | 3654 | if (default_noexec && |
892e8cac SS |
3655 | (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || |
3656 | (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3657 | /* |
3658 | * We are making executable an anonymous mapping or a | |
3659 | * private file mapping that will also be writable. | |
3660 | * This has an additional check. | |
3661 | */ | |
6b6bc620 SS |
3662 | rc = avc_has_perm(&selinux_state, |
3663 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3664 | PROCESS__EXECMEM, NULL); |
1da177e4 | 3665 | if (rc) |
d84f4f99 | 3666 | goto error; |
1da177e4 | 3667 | } |
1da177e4 LT |
3668 | |
3669 | if (file) { | |
3670 | /* read access is always possible with a mapping */ | |
3671 | u32 av = FILE__READ; | |
3672 | ||
3673 | /* write access only matters if the mapping is shared */ | |
3674 | if (shared && (prot & PROT_WRITE)) | |
3675 | av |= FILE__WRITE; | |
3676 | ||
3677 | if (prot & PROT_EXEC) | |
3678 | av |= FILE__EXECUTE; | |
3679 | ||
88e67f3b | 3680 | return file_has_perm(cred, file, av); |
1da177e4 | 3681 | } |
d84f4f99 DH |
3682 | |
3683 | error: | |
3684 | return rc; | |
1da177e4 LT |
3685 | } |
3686 | ||
e5467859 | 3687 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3688 | { |
b1d9e6b0 | 3689 | int rc = 0; |
1da177e4 | 3690 | |
a2551df7 | 3691 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
98883bfd | 3692 | u32 sid = current_sid(); |
6b6bc620 SS |
3693 | rc = avc_has_perm(&selinux_state, |
3694 | sid, sid, SECCLASS_MEMPROTECT, | |
ed032189 | 3695 | MEMPROTECT__MMAP_ZERO, NULL); |
84336d1a EP |
3696 | } |
3697 | ||
98883bfd | 3698 | return rc; |
e5467859 | 3699 | } |
1da177e4 | 3700 | |
e5467859 AV |
3701 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3702 | unsigned long prot, unsigned long flags) | |
3703 | { | |
3ba4bf5f SS |
3704 | struct common_audit_data ad; |
3705 | int rc; | |
3706 | ||
3707 | if (file) { | |
3708 | ad.type = LSM_AUDIT_DATA_FILE; | |
3709 | ad.u.file = file; | |
3710 | rc = inode_has_perm(current_cred(), file_inode(file), | |
3711 | FILE__MAP, &ad); | |
3712 | if (rc) | |
3713 | return rc; | |
3714 | } | |
3715 | ||
aa8e712c | 3716 | if (selinux_state.checkreqprot) |
1da177e4 LT |
3717 | prot = reqprot; |
3718 | ||
3719 | return file_map_prot_check(file, prot, | |
3720 | (flags & MAP_TYPE) == MAP_SHARED); | |
3721 | } | |
3722 | ||
3723 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3724 | unsigned long reqprot, | |
3725 | unsigned long prot) | |
3726 | { | |
88e67f3b | 3727 | const struct cred *cred = current_cred(); |
be0554c9 | 3728 | u32 sid = cred_sid(cred); |
1da177e4 | 3729 | |
aa8e712c | 3730 | if (selinux_state.checkreqprot) |
1da177e4 LT |
3731 | prot = reqprot; |
3732 | ||
fcaaade1 SS |
3733 | if (default_noexec && |
3734 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3735 | int rc = 0; |
db4c9641 SS |
3736 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3737 | vma->vm_end <= vma->vm_mm->brk) { | |
6b6bc620 SS |
3738 | rc = avc_has_perm(&selinux_state, |
3739 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3740 | PROCESS__EXECHEAP, NULL); |
db4c9641 | 3741 | } else if (!vma->vm_file && |
c2316dbf SS |
3742 | ((vma->vm_start <= vma->vm_mm->start_stack && |
3743 | vma->vm_end >= vma->vm_mm->start_stack) || | |
d17af505 | 3744 | vma_is_stack_for_current(vma))) { |
6b6bc620 SS |
3745 | rc = avc_has_perm(&selinux_state, |
3746 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3747 | PROCESS__EXECSTACK, NULL); |
db4c9641 SS |
3748 | } else if (vma->vm_file && vma->anon_vma) { |
3749 | /* | |
3750 | * We are making executable a file mapping that has | |
3751 | * had some COW done. Since pages might have been | |
3752 | * written, check ability to execute the possibly | |
3753 | * modified content. This typically should only | |
3754 | * occur for text relocations. | |
3755 | */ | |
d84f4f99 | 3756 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3757 | } |