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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 |
6c5a682e | 112 | static int selinux_enforcing_boot __initdata; |
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 | ||
6c5a682e | 126 | int selinux_enabled_boot __initdata = 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)) |
6c5a682e | 132 | selinux_enabled_boot = 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 | ||
5d226df4 AG |
241 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); |
242 | ||
243 | /* | |
244 | * Try reloading inode security labels that have been marked as invalid. The | |
245 | * @may_sleep parameter indicates when sleeping and thus reloading labels is | |
42059112 | 246 | * allowed; when set to false, returns -ECHILD when the label is |
e9193288 | 247 | * invalid. The @dentry parameter should be set to a dentry of the inode. |
5d226df4 AG |
248 | */ |
249 | static int __inode_security_revalidate(struct inode *inode, | |
e9193288 | 250 | struct dentry *dentry, |
5d226df4 AG |
251 | bool may_sleep) |
252 | { | |
80788c22 | 253 | struct inode_security_struct *isec = selinux_inode(inode); |
5d226df4 AG |
254 | |
255 | might_sleep_if(may_sleep); | |
256 | ||
65cddd50 | 257 | if (selinux_initialized(&selinux_state) && |
aa8e712c | 258 | isec->initialized != LABEL_INITIALIZED) { |
5d226df4 AG |
259 | if (!may_sleep) |
260 | return -ECHILD; | |
261 | ||
262 | /* | |
263 | * Try reloading the inode security label. This will fail if | |
264 | * @opt_dentry is NULL and no dentry for this inode can be | |
265 | * found; in that case, continue using the old label. | |
266 | */ | |
e9193288 | 267 | inode_doinit_with_dentry(inode, dentry); |
5d226df4 AG |
268 | } |
269 | return 0; | |
270 | } | |
271 | ||
5d226df4 AG |
272 | static struct inode_security_struct *inode_security_novalidate(struct inode *inode) |
273 | { | |
80788c22 | 274 | return selinux_inode(inode); |
5d226df4 AG |
275 | } |
276 | ||
277 | static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) | |
278 | { | |
279 | int error; | |
280 | ||
281 | error = __inode_security_revalidate(inode, NULL, !rcu); | |
282 | if (error) | |
283 | return ERR_PTR(error); | |
80788c22 | 284 | return selinux_inode(inode); |
5d226df4 AG |
285 | } |
286 | ||
83da53c5 AG |
287 | /* |
288 | * Get the security label of an inode. | |
289 | */ | |
290 | static struct inode_security_struct *inode_security(struct inode *inode) | |
291 | { | |
5d226df4 | 292 | __inode_security_revalidate(inode, NULL, true); |
80788c22 | 293 | return selinux_inode(inode); |
83da53c5 AG |
294 | } |
295 | ||
2c97165b PM |
296 | static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) |
297 | { | |
298 | struct inode *inode = d_backing_inode(dentry); | |
299 | ||
80788c22 | 300 | return selinux_inode(inode); |
2c97165b PM |
301 | } |
302 | ||
83da53c5 AG |
303 | /* |
304 | * Get the security label of a dentry's backing inode. | |
305 | */ | |
306 | static struct inode_security_struct *backing_inode_security(struct dentry *dentry) | |
307 | { | |
308 | struct inode *inode = d_backing_inode(dentry); | |
309 | ||
5d226df4 | 310 | __inode_security_revalidate(inode, dentry, true); |
80788c22 | 311 | return selinux_inode(inode); |
83da53c5 AG |
312 | } |
313 | ||
1da177e4 LT |
314 | static void inode_free_security(struct inode *inode) |
315 | { | |
80788c22 | 316 | struct inode_security_struct *isec = selinux_inode(inode); |
afb1cbe3 | 317 | struct superblock_security_struct *sbsec; |
1da177e4 | 318 | |
afb1cbe3 CS |
319 | if (!isec) |
320 | return; | |
321 | sbsec = inode->i_sb->s_security; | |
9629d04a WL |
322 | /* |
323 | * As not all inode security structures are in a list, we check for | |
324 | * empty list outside of the lock to make sure that we won't waste | |
325 | * time taking a lock doing nothing. | |
326 | * | |
327 | * The list_del_init() function can be safely called more than once. | |
328 | * It should not be possible for this function to be called with | |
329 | * concurrent list_add(), but for better safety against future changes | |
330 | * in the code, we use list_empty_careful() here. | |
331 | */ | |
332 | if (!list_empty_careful(&isec->list)) { | |
333 | spin_lock(&sbsec->isec_lock); | |
1da177e4 | 334 | list_del_init(&isec->list); |
9629d04a WL |
335 | spin_unlock(&sbsec->isec_lock); |
336 | } | |
1da177e4 LT |
337 | } |
338 | ||
1da177e4 LT |
339 | static void superblock_free_security(struct super_block *sb) |
340 | { | |
341 | struct superblock_security_struct *sbsec = sb->s_security; | |
1da177e4 LT |
342 | sb->s_security = NULL; |
343 | kfree(sbsec); | |
344 | } | |
345 | ||
bd323655 AV |
346 | struct selinux_mnt_opts { |
347 | const char *fscontext, *context, *rootcontext, *defcontext; | |
348 | }; | |
349 | ||
204cc0cc AV |
350 | static void selinux_free_mnt_opts(void *mnt_opts) |
351 | { | |
bd323655 AV |
352 | struct selinux_mnt_opts *opts = mnt_opts; |
353 | kfree(opts->fscontext); | |
354 | kfree(opts->context); | |
355 | kfree(opts->rootcontext); | |
356 | kfree(opts->defcontext); | |
204cc0cc AV |
357 | kfree(opts); |
358 | } | |
359 | ||
1da177e4 | 360 | enum { |
31e87930 | 361 | Opt_error = -1, |
442155c1 DH |
362 | Opt_context = 0, |
363 | Opt_defcontext = 1, | |
1da177e4 | 364 | Opt_fscontext = 2, |
442155c1 DH |
365 | Opt_rootcontext = 3, |
366 | Opt_seclabel = 4, | |
1da177e4 LT |
367 | }; |
368 | ||
da3d76ab | 369 | #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} |
169d68ef AV |
370 | static struct { |
371 | const char *name; | |
372 | int len; | |
373 | int opt; | |
374 | bool has_arg; | |
375 | } tokens[] = { | |
da3d76ab AV |
376 | A(context, true), |
377 | A(fscontext, true), | |
378 | A(defcontext, true), | |
379 | A(rootcontext, true), | |
380 | A(seclabel, false), | |
1da177e4 | 381 | }; |
169d68ef AV |
382 | #undef A |
383 | ||
384 | static int match_opt_prefix(char *s, int l, char **arg) | |
385 | { | |
386 | int i; | |
387 | ||
388 | for (i = 0; i < ARRAY_SIZE(tokens); i++) { | |
389 | size_t len = tokens[i].len; | |
390 | if (len > l || memcmp(s, tokens[i].name, len)) | |
391 | continue; | |
392 | if (tokens[i].has_arg) { | |
393 | if (len == l || s[len] != '=') | |
394 | continue; | |
395 | *arg = s + len + 1; | |
396 | } else if (len != l) | |
397 | continue; | |
398 | return tokens[i].opt; | |
399 | } | |
400 | return Opt_error; | |
401 | } | |
1da177e4 LT |
402 | |
403 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
404 | ||
c312feb2 EP |
405 | static int may_context_mount_sb_relabel(u32 sid, |
406 | struct superblock_security_struct *sbsec, | |
275bb41e | 407 | const struct cred *cred) |
c312feb2 | 408 | { |
0c6cfa62 | 409 | const struct task_security_struct *tsec = selinux_cred(cred); |
c312feb2 EP |
410 | int rc; |
411 | ||
6b6bc620 SS |
412 | rc = avc_has_perm(&selinux_state, |
413 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
414 | FILESYSTEM__RELABELFROM, NULL); |
415 | if (rc) | |
416 | return rc; | |
417 | ||
6b6bc620 SS |
418 | rc = avc_has_perm(&selinux_state, |
419 | tsec->sid, sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
420 | FILESYSTEM__RELABELTO, NULL); |
421 | return rc; | |
422 | } | |
423 | ||
0808925e EP |
424 | static int may_context_mount_inode_relabel(u32 sid, |
425 | struct superblock_security_struct *sbsec, | |
275bb41e | 426 | const struct cred *cred) |
0808925e | 427 | { |
0c6cfa62 | 428 | const struct task_security_struct *tsec = selinux_cred(cred); |
0808925e | 429 | int rc; |
6b6bc620 SS |
430 | rc = avc_has_perm(&selinux_state, |
431 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
432 | FILESYSTEM__RELABELFROM, NULL); |
433 | if (rc) | |
434 | return rc; | |
435 | ||
6b6bc620 SS |
436 | rc = avc_has_perm(&selinux_state, |
437 | sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
438 | FILESYSTEM__ASSOCIATE, NULL); |
439 | return rc; | |
440 | } | |
441 | ||
a83d6dda | 442 | static int selinux_is_genfs_special_handling(struct super_block *sb) |
b43e725d | 443 | { |
a83d6dda OM |
444 | /* Special handling. Genfs but also in-core setxattr handler */ |
445 | return !strcmp(sb->s_type->name, "sysfs") || | |
d5f3a5f6 MS |
446 | !strcmp(sb->s_type->name, "pstore") || |
447 | !strcmp(sb->s_type->name, "debugfs") || | |
a2c7c6fb | 448 | !strcmp(sb->s_type->name, "tracefs") || |
2651225b | 449 | !strcmp(sb->s_type->name, "rootfs") || |
aa8e712c | 450 | (selinux_policycap_cgroupseclabel() && |
2651225b SS |
451 | (!strcmp(sb->s_type->name, "cgroup") || |
452 | !strcmp(sb->s_type->name, "cgroup2"))); | |
b43e725d EP |
453 | } |
454 | ||
a83d6dda OM |
455 | static int selinux_is_sblabel_mnt(struct super_block *sb) |
456 | { | |
457 | struct superblock_security_struct *sbsec = sb->s_security; | |
458 | ||
459 | /* | |
460 | * IMPORTANT: Double-check logic in this function when adding a new | |
461 | * SECURITY_FS_USE_* definition! | |
462 | */ | |
463 | BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); | |
464 | ||
465 | switch (sbsec->behavior) { | |
466 | case SECURITY_FS_USE_XATTR: | |
467 | case SECURITY_FS_USE_TRANS: | |
468 | case SECURITY_FS_USE_TASK: | |
469 | case SECURITY_FS_USE_NATIVE: | |
470 | return 1; | |
471 | ||
472 | case SECURITY_FS_USE_GENFS: | |
473 | return selinux_is_genfs_special_handling(sb); | |
474 | ||
475 | /* Never allow relabeling on context mounts */ | |
476 | case SECURITY_FS_USE_MNTPOINT: | |
477 | case SECURITY_FS_USE_NONE: | |
478 | default: | |
479 | return 0; | |
480 | } | |
481 | } | |
482 | ||
c9180a57 | 483 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 484 | { |
1da177e4 | 485 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 | 486 | struct dentry *root = sb->s_root; |
c6f493d6 | 487 | struct inode *root_inode = d_backing_inode(root); |
c9180a57 | 488 | int rc = 0; |
1da177e4 | 489 | |
c9180a57 EP |
490 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
491 | /* Make sure that the xattr handler exists and that no | |
492 | error other than -ENODATA is returned by getxattr on | |
493 | the root directory. -ENODATA is ok, as this may be | |
494 | the first boot of the SELinux kernel before we have | |
495 | assigned xattr values to the filesystem. */ | |
5d6c3191 | 496 | if (!(root_inode->i_opflags & IOP_XATTR)) { |
c103a91e | 497 | pr_warn("SELinux: (dev %s, type %s) has no " |
29b1deb2 | 498 | "xattr support\n", sb->s_id, sb->s_type->name); |
c9180a57 EP |
499 | rc = -EOPNOTSUPP; |
500 | goto out; | |
501 | } | |
5d6c3191 AG |
502 | |
503 | rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); | |
c9180a57 EP |
504 | if (rc < 0 && rc != -ENODATA) { |
505 | if (rc == -EOPNOTSUPP) | |
c103a91e | 506 | pr_warn("SELinux: (dev %s, type " |
29b1deb2 LT |
507 | "%s) has no security xattr handler\n", |
508 | sb->s_id, sb->s_type->name); | |
c9180a57 | 509 | else |
c103a91e | 510 | pr_warn("SELinux: (dev %s, type " |
29b1deb2 LT |
511 | "%s) getxattr errno %d\n", sb->s_id, |
512 | sb->s_type->name, -rc); | |
c9180a57 EP |
513 | goto out; |
514 | } | |
515 | } | |
1da177e4 | 516 | |
eadcabc6 | 517 | sbsec->flags |= SE_SBINITIALIZED; |
0b4d3452 SM |
518 | |
519 | /* | |
520 | * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply | |
521 | * leave the flag untouched because sb_clone_mnt_opts might be handing | |
522 | * us a superblock that needs the flag to be cleared. | |
523 | */ | |
b43e725d | 524 | if (selinux_is_sblabel_mnt(sb)) |
12f348b9 | 525 | sbsec->flags |= SBLABEL_MNT; |
0b4d3452 SM |
526 | else |
527 | sbsec->flags &= ~SBLABEL_MNT; | |
ddd29ec6 | 528 | |
c9180a57 EP |
529 | /* Initialize the root inode. */ |
530 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 531 | |
c9180a57 EP |
532 | /* Initialize any other inodes associated with the superblock, e.g. |
533 | inodes created prior to initial policy load or inodes created | |
534 | during get_sb by a pseudo filesystem that directly | |
535 | populates itself. */ | |
536 | spin_lock(&sbsec->isec_lock); | |
8d64124a | 537 | while (!list_empty(&sbsec->isec_head)) { |
c9180a57 | 538 | struct inode_security_struct *isec = |
8d64124a | 539 | list_first_entry(&sbsec->isec_head, |
c9180a57 EP |
540 | struct inode_security_struct, list); |
541 | struct inode *inode = isec->inode; | |
923190d3 | 542 | list_del_init(&isec->list); |
c9180a57 EP |
543 | spin_unlock(&sbsec->isec_lock); |
544 | inode = igrab(inode); | |
545 | if (inode) { | |
546 | if (!IS_PRIVATE(inode)) | |
cb89e246 | 547 | inode_doinit_with_dentry(inode, NULL); |
c9180a57 EP |
548 | iput(inode); |
549 | } | |
550 | spin_lock(&sbsec->isec_lock); | |
c9180a57 EP |
551 | } |
552 | spin_unlock(&sbsec->isec_lock); | |
553 | out: | |
554 | return rc; | |
555 | } | |
1da177e4 | 556 | |
c9180a57 EP |
557 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
558 | u32 old_sid, u32 new_sid) | |
559 | { | |
0d90a7ec DQ |
560 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
561 | ||
c9180a57 | 562 | /* check if the old mount command had the same options */ |
0d90a7ec | 563 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
564 | if (!(sbsec->flags & flag) || |
565 | (old_sid != new_sid)) | |
566 | return 1; | |
567 | ||
568 | /* check if we were passed the same options twice, | |
569 | * aka someone passed context=a,context=b | |
570 | */ | |
0d90a7ec DQ |
571 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
572 | if (mnt_flags & flag) | |
c9180a57 EP |
573 | return 1; |
574 | return 0; | |
575 | } | |
e0007529 | 576 | |
bd323655 AV |
577 | static int parse_sid(struct super_block *sb, const char *s, u32 *sid) |
578 | { | |
579 | int rc = security_context_str_to_sid(&selinux_state, s, | |
580 | sid, GFP_KERNEL); | |
581 | if (rc) | |
582 | pr_warn("SELinux: security_context_str_to_sid" | |
583 | "(%s) failed for (dev %s, type %s) errno=%d\n", | |
584 | s, sb->s_id, sb->s_type->name, rc); | |
585 | return rc; | |
586 | } | |
587 | ||
c9180a57 EP |
588 | /* |
589 | * Allow filesystems with binary mount data to explicitly set mount point | |
590 | * labeling information. | |
591 | */ | |
e0007529 | 592 | static int selinux_set_mnt_opts(struct super_block *sb, |
204cc0cc | 593 | void *mnt_opts, |
649f6e77 DQ |
594 | unsigned long kern_flags, |
595 | unsigned long *set_kern_flags) | |
c9180a57 | 596 | { |
275bb41e | 597 | const struct cred *cred = current_cred(); |
c9180a57 | 598 | struct superblock_security_struct *sbsec = sb->s_security; |
83da53c5 | 599 | struct dentry *root = sbsec->sb->s_root; |
bd323655 | 600 | struct selinux_mnt_opts *opts = mnt_opts; |
2c97165b | 601 | struct inode_security_struct *root_isec; |
c9180a57 EP |
602 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
603 | u32 defcontext_sid = 0; | |
bd323655 | 604 | int rc = 0; |
c9180a57 EP |
605 | |
606 | mutex_lock(&sbsec->lock); | |
607 | ||
65cddd50 | 608 | if (!selinux_initialized(&selinux_state)) { |
bd323655 | 609 | if (!opts) { |
c9180a57 EP |
610 | /* Defer initialization until selinux_complete_init, |
611 | after the initial policy is loaded and the security | |
612 | server is ready to handle calls. */ | |
c9180a57 EP |
613 | goto out; |
614 | } | |
615 | rc = -EINVAL; | |
c103a91e | 616 | pr_warn("SELinux: Unable to set superblock options " |
744ba35e | 617 | "before the security server is initialized\n"); |
1da177e4 | 618 | goto out; |
c9180a57 | 619 | } |
649f6e77 DQ |
620 | if (kern_flags && !set_kern_flags) { |
621 | /* Specifying internal flags without providing a place to | |
622 | * place the results is not allowed */ | |
623 | rc = -EINVAL; | |
624 | goto out; | |
625 | } | |
1da177e4 | 626 | |
e0007529 EP |
627 | /* |
628 | * Binary mount data FS will come through this function twice. Once | |
629 | * from an explicit call and once from the generic calls from the vfs. | |
630 | * Since the generic VFS calls will not contain any security mount data | |
631 | * we need to skip the double mount verification. | |
632 | * | |
633 | * This does open a hole in which we will not notice if the first | |
634 | * mount using this sb set explict options and a second mount using | |
635 | * this sb does not set any security options. (The first options | |
636 | * will be used for both mounts) | |
637 | */ | |
0d90a7ec | 638 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
bd323655 | 639 | && !opts) |
f5269710 | 640 | goto out; |
e0007529 | 641 | |
2c97165b PM |
642 | root_isec = backing_inode_security_novalidate(root); |
643 | ||
c9180a57 EP |
644 | /* |
645 | * parse the mount options, check if they are valid sids. | |
646 | * also check if someone is trying to mount the same sb more | |
647 | * than once with different security options. | |
648 | */ | |
bd323655 AV |
649 | if (opts) { |
650 | if (opts->fscontext) { | |
651 | rc = parse_sid(sb, opts->fscontext, &fscontext_sid); | |
652 | if (rc) | |
653 | goto out; | |
c9180a57 EP |
654 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, |
655 | fscontext_sid)) | |
656 | goto out_double_mount; | |
c9180a57 | 657 | sbsec->flags |= FSCONTEXT_MNT; |
bd323655 AV |
658 | } |
659 | if (opts->context) { | |
660 | rc = parse_sid(sb, opts->context, &context_sid); | |
661 | if (rc) | |
662 | goto out; | |
c9180a57 EP |
663 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, |
664 | context_sid)) | |
665 | goto out_double_mount; | |
c9180a57 | 666 | sbsec->flags |= CONTEXT_MNT; |
bd323655 AV |
667 | } |
668 | if (opts->rootcontext) { | |
669 | rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid); | |
670 | if (rc) | |
671 | goto out; | |
c9180a57 EP |
672 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, |
673 | rootcontext_sid)) | |
674 | goto out_double_mount; | |
c9180a57 | 675 | sbsec->flags |= ROOTCONTEXT_MNT; |
bd323655 AV |
676 | } |
677 | if (opts->defcontext) { | |
678 | rc = parse_sid(sb, opts->defcontext, &defcontext_sid); | |
679 | if (rc) | |
680 | goto out; | |
c9180a57 EP |
681 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, |
682 | defcontext_sid)) | |
683 | goto out_double_mount; | |
c9180a57 | 684 | sbsec->flags |= DEFCONTEXT_MNT; |
1da177e4 | 685 | } |
c9180a57 EP |
686 | } |
687 | ||
0d90a7ec | 688 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 689 | /* previously mounted with options, but not on this attempt? */ |
bd323655 | 690 | if ((sbsec->flags & SE_MNTMASK) && !opts) |
c9180a57 EP |
691 | goto out_double_mount; |
692 | rc = 0; | |
693 | goto out; | |
694 | } | |
695 | ||
089be43e | 696 | if (strcmp(sb->s_type->name, "proc") == 0) |
134509d5 SS |
697 | sbsec->flags |= SE_SBPROC | SE_SBGENFS; |
698 | ||
8e014720 | 699 | if (!strcmp(sb->s_type->name, "debugfs") || |
6a391183 | 700 | !strcmp(sb->s_type->name, "tracefs") || |
a20456ae | 701 | !strcmp(sb->s_type->name, "binder") || |
b754026b OM |
702 | !strcmp(sb->s_type->name, "pstore")) |
703 | sbsec->flags |= SE_SBGENFS; | |
704 | ||
705 | if (!strcmp(sb->s_type->name, "sysfs") || | |
901ef845 AM |
706 | !strcmp(sb->s_type->name, "cgroup") || |
707 | !strcmp(sb->s_type->name, "cgroup2")) | |
b754026b | 708 | sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; |
c9180a57 | 709 | |
eb9ae686 DQ |
710 | if (!sbsec->behavior) { |
711 | /* | |
712 | * Determine the labeling behavior to use for this | |
713 | * filesystem type. | |
714 | */ | |
aa8e712c | 715 | rc = security_fs_use(&selinux_state, sb); |
eb9ae686 | 716 | if (rc) { |
c103a91e | 717 | pr_warn("%s: security_fs_use(%s) returned %d\n", |
eb9ae686 DQ |
718 | __func__, sb->s_type->name, rc); |
719 | goto out; | |
720 | } | |
c9180a57 | 721 | } |
aad82892 SF |
722 | |
723 | /* | |
01593d32 SS |
724 | * If this is a user namespace mount and the filesystem type is not |
725 | * explicitly whitelisted, then no contexts are allowed on the command | |
726 | * line and security labels must be ignored. | |
aad82892 | 727 | */ |
01593d32 SS |
728 | if (sb->s_user_ns != &init_user_ns && |
729 | strcmp(sb->s_type->name, "tmpfs") && | |
730 | strcmp(sb->s_type->name, "ramfs") && | |
731 | strcmp(sb->s_type->name, "devpts")) { | |
aad82892 SF |
732 | if (context_sid || fscontext_sid || rootcontext_sid || |
733 | defcontext_sid) { | |
734 | rc = -EACCES; | |
735 | goto out; | |
736 | } | |
737 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { | |
738 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; | |
aa8e712c SS |
739 | rc = security_transition_sid(&selinux_state, |
740 | current_sid(), | |
741 | current_sid(), | |
aad82892 SF |
742 | SECCLASS_FILE, NULL, |
743 | &sbsec->mntpoint_sid); | |
744 | if (rc) | |
745 | goto out; | |
746 | } | |
747 | goto out_set_opts; | |
748 | } | |
749 | ||
c9180a57 EP |
750 | /* sets the context of the superblock for the fs being mounted. */ |
751 | if (fscontext_sid) { | |
275bb41e | 752 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
1da177e4 | 753 | if (rc) |
c9180a57 | 754 | goto out; |
1da177e4 | 755 | |
c9180a57 | 756 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
757 | } |
758 | ||
759 | /* | |
760 | * Switch to using mount point labeling behavior. | |
761 | * sets the label used on all file below the mountpoint, and will set | |
762 | * the superblock context if not already set. | |
763 | */ | |
eb9ae686 DQ |
764 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { |
765 | sbsec->behavior = SECURITY_FS_USE_NATIVE; | |
766 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
767 | } | |
768 | ||
c9180a57 EP |
769 | if (context_sid) { |
770 | if (!fscontext_sid) { | |
275bb41e DH |
771 | rc = may_context_mount_sb_relabel(context_sid, sbsec, |
772 | cred); | |
b04ea3ce | 773 | if (rc) |
c9180a57 EP |
774 | goto out; |
775 | sbsec->sid = context_sid; | |
b04ea3ce | 776 | } else { |
275bb41e DH |
777 | rc = may_context_mount_inode_relabel(context_sid, sbsec, |
778 | cred); | |
b04ea3ce | 779 | if (rc) |
c9180a57 | 780 | goto out; |
b04ea3ce | 781 | } |
c9180a57 EP |
782 | if (!rootcontext_sid) |
783 | rootcontext_sid = context_sid; | |
1da177e4 | 784 | |
c9180a57 | 785 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 786 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
787 | } |
788 | ||
c9180a57 | 789 | if (rootcontext_sid) { |
275bb41e DH |
790 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
791 | cred); | |
0808925e | 792 | if (rc) |
c9180a57 | 793 | goto out; |
0808925e | 794 | |
c9180a57 | 795 | root_isec->sid = rootcontext_sid; |
6f3be9f5 | 796 | root_isec->initialized = LABEL_INITIALIZED; |
0808925e EP |
797 | } |
798 | ||
c9180a57 | 799 | if (defcontext_sid) { |
eb9ae686 DQ |
800 | if (sbsec->behavior != SECURITY_FS_USE_XATTR && |
801 | sbsec->behavior != SECURITY_FS_USE_NATIVE) { | |
c9180a57 | 802 | rc = -EINVAL; |
c103a91e | 803 | pr_warn("SELinux: defcontext option is " |
c9180a57 EP |
804 | "invalid for this filesystem type\n"); |
805 | goto out; | |
1da177e4 LT |
806 | } |
807 | ||
c9180a57 EP |
808 | if (defcontext_sid != sbsec->def_sid) { |
809 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
275bb41e | 810 | sbsec, cred); |
c9180a57 EP |
811 | if (rc) |
812 | goto out; | |
813 | } | |
1da177e4 | 814 | |
c9180a57 | 815 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
816 | } |
817 | ||
aad82892 | 818 | out_set_opts: |
c9180a57 | 819 | rc = sb_finish_set_opts(sb); |
1da177e4 | 820 | out: |
c9180a57 | 821 | mutex_unlock(&sbsec->lock); |
1da177e4 | 822 | return rc; |
c9180a57 EP |
823 | out_double_mount: |
824 | rc = -EINVAL; | |
c103a91e | 825 | pr_warn("SELinux: mount invalid. Same superblock, different " |
bd323655 AV |
826 | "security settings for (dev %s, type %s)\n", sb->s_id, |
827 | sb->s_type->name); | |
c9180a57 | 828 | goto out; |
1da177e4 LT |
829 | } |
830 | ||
094f7b69 JL |
831 | static int selinux_cmp_sb_context(const struct super_block *oldsb, |
832 | const struct super_block *newsb) | |
833 | { | |
834 | struct superblock_security_struct *old = oldsb->s_security; | |
835 | struct superblock_security_struct *new = newsb->s_security; | |
836 | char oldflags = old->flags & SE_MNTMASK; | |
837 | char newflags = new->flags & SE_MNTMASK; | |
838 | ||
839 | if (oldflags != newflags) | |
840 | goto mismatch; | |
841 | if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) | |
842 | goto mismatch; | |
843 | if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) | |
844 | goto mismatch; | |
845 | if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) | |
846 | goto mismatch; | |
847 | if (oldflags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
848 | struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); |
849 | struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); | |
094f7b69 JL |
850 | if (oldroot->sid != newroot->sid) |
851 | goto mismatch; | |
852 | } | |
853 | return 0; | |
854 | mismatch: | |
c103a91e | 855 | pr_warn("SELinux: mount invalid. Same superblock, " |
094f7b69 JL |
856 | "different security settings for (dev %s, " |
857 | "type %s)\n", newsb->s_id, newsb->s_type->name); | |
858 | return -EBUSY; | |
859 | } | |
860 | ||
861 | static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, | |
0b4d3452 SM |
862 | struct super_block *newsb, |
863 | unsigned long kern_flags, | |
864 | unsigned long *set_kern_flags) | |
1da177e4 | 865 | { |
0b4d3452 | 866 | int rc = 0; |
c9180a57 EP |
867 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
868 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 869 | |
c9180a57 EP |
870 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
871 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
872 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 873 | |
0f5e6420 EP |
874 | /* |
875 | * if the parent was able to be mounted it clearly had no special lsm | |
e8c26255 | 876 | * mount options. thus we can safely deal with this superblock later |
0f5e6420 | 877 | */ |
65cddd50 | 878 | if (!selinux_initialized(&selinux_state)) |
094f7b69 | 879 | return 0; |
c9180a57 | 880 | |
0b4d3452 SM |
881 | /* |
882 | * Specifying internal flags without providing a place to | |
883 | * place the results is not allowed. | |
884 | */ | |
885 | if (kern_flags && !set_kern_flags) | |
886 | return -EINVAL; | |
887 | ||
c9180a57 | 888 | /* how can we clone if the old one wasn't set up?? */ |
0d90a7ec | 889 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
c9180a57 | 890 | |
094f7b69 | 891 | /* if fs is reusing a sb, make sure that the contexts match */ |
3815a245 BF |
892 | if (newsbsec->flags & SE_SBINITIALIZED) { |
893 | if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) | |
894 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
094f7b69 | 895 | return selinux_cmp_sb_context(oldsb, newsb); |
3815a245 | 896 | } |
5a552617 | 897 | |
c9180a57 EP |
898 | mutex_lock(&newsbsec->lock); |
899 | ||
900 | newsbsec->flags = oldsbsec->flags; | |
901 | ||
902 | newsbsec->sid = oldsbsec->sid; | |
903 | newsbsec->def_sid = oldsbsec->def_sid; | |
904 | newsbsec->behavior = oldsbsec->behavior; | |
905 | ||
0b4d3452 SM |
906 | if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && |
907 | !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { | |
aa8e712c | 908 | rc = security_fs_use(&selinux_state, newsb); |
0b4d3452 SM |
909 | if (rc) |
910 | goto out; | |
911 | } | |
912 | ||
913 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { | |
914 | newsbsec->behavior = SECURITY_FS_USE_NATIVE; | |
915 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
916 | } | |
917 | ||
c9180a57 EP |
918 | if (set_context) { |
919 | u32 sid = oldsbsec->mntpoint_sid; | |
920 | ||
921 | if (!set_fscontext) | |
922 | newsbsec->sid = sid; | |
923 | if (!set_rootcontext) { | |
83da53c5 | 924 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); |
c9180a57 EP |
925 | newisec->sid = sid; |
926 | } | |
927 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 928 | } |
c9180a57 | 929 | if (set_rootcontext) { |
83da53c5 AG |
930 | const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); |
931 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); | |
1da177e4 | 932 | |
c9180a57 | 933 | newisec->sid = oldisec->sid; |
1da177e4 LT |
934 | } |
935 | ||
c9180a57 | 936 | sb_finish_set_opts(newsb); |
0b4d3452 | 937 | out: |
c9180a57 | 938 | mutex_unlock(&newsbsec->lock); |
0b4d3452 | 939 | return rc; |
c9180a57 EP |
940 | } |
941 | ||
ba641862 | 942 | static int selinux_add_opt(int token, const char *s, void **mnt_opts) |
c9180a57 | 943 | { |
ba641862 | 944 | struct selinux_mnt_opts *opts = *mnt_opts; |
1da177e4 | 945 | |
da3d76ab | 946 | if (token == Opt_seclabel) /* eaten and completely ignored */ |
169d68ef | 947 | return 0; |
e0007529 | 948 | |
ba641862 AV |
949 | if (!opts) { |
950 | opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); | |
951 | if (!opts) | |
952 | return -ENOMEM; | |
953 | *mnt_opts = opts; | |
c9180a57 | 954 | } |
ba641862 AV |
955 | if (!s) |
956 | return -ENOMEM; | |
957 | switch (token) { | |
958 | case Opt_context: | |
959 | if (opts->context || opts->defcontext) | |
960 | goto Einval; | |
961 | opts->context = s; | |
962 | break; | |
963 | case Opt_fscontext: | |
964 | if (opts->fscontext) | |
965 | goto Einval; | |
966 | opts->fscontext = s; | |
967 | break; | |
968 | case Opt_rootcontext: | |
969 | if (opts->rootcontext) | |
970 | goto Einval; | |
971 | opts->rootcontext = s; | |
972 | break; | |
973 | case Opt_defcontext: | |
974 | if (opts->context || opts->defcontext) | |
975 | goto Einval; | |
976 | opts->defcontext = s; | |
977 | break; | |
c9180a57 | 978 | } |
e0007529 | 979 | return 0; |
ba641862 AV |
980 | Einval: |
981 | pr_warn(SEL_MOUNT_FAIL_MSG); | |
ba641862 | 982 | return -EINVAL; |
1da177e4 | 983 | } |
e0007529 | 984 | |
757cbe59 AV |
985 | static int selinux_add_mnt_opt(const char *option, const char *val, int len, |
986 | void **mnt_opts) | |
c9180a57 | 987 | { |
757cbe59 AV |
988 | int token = Opt_error; |
989 | int rc, i; | |
e0007529 | 990 | |
757cbe59 AV |
991 | for (i = 0; i < ARRAY_SIZE(tokens); i++) { |
992 | if (strcmp(option, tokens[i].name) == 0) { | |
993 | token = tokens[i].opt; | |
994 | break; | |
169d68ef | 995 | } |
757cbe59 | 996 | } |
e0007529 | 997 | |
757cbe59 AV |
998 | if (token == Opt_error) |
999 | return -EINVAL; | |
e0007529 | 1000 | |
e2e0e097 | 1001 | if (token != Opt_seclabel) { |
757cbe59 | 1002 | val = kmemdup_nul(val, len, GFP_KERNEL); |
e2e0e097 GZ |
1003 | if (!val) { |
1004 | rc = -ENOMEM; | |
1005 | goto free_opt; | |
1006 | } | |
1007 | } | |
757cbe59 AV |
1008 | rc = selinux_add_opt(token, val, mnt_opts); |
1009 | if (unlikely(rc)) { | |
1010 | kfree(val); | |
e2e0e097 GZ |
1011 | goto free_opt; |
1012 | } | |
1013 | return rc; | |
1014 | ||
1015 | free_opt: | |
1016 | if (*mnt_opts) { | |
1017 | selinux_free_mnt_opts(*mnt_opts); | |
1018 | *mnt_opts = NULL; | |
1da177e4 | 1019 | } |
e0007529 EP |
1020 | return rc; |
1021 | } | |
1da177e4 | 1022 | |
e3489f89 | 1023 | static int show_sid(struct seq_file *m, u32 sid) |
2069f457 | 1024 | { |
e3489f89 AV |
1025 | char *context = NULL; |
1026 | u32 len; | |
1027 | int rc; | |
11689d47 | 1028 | |
e3489f89 AV |
1029 | rc = security_sid_to_context(&selinux_state, sid, |
1030 | &context, &len); | |
1031 | if (!rc) { | |
1032 | bool has_comma = context && strchr(context, ','); | |
2069f457 | 1033 | |
442155c1 | 1034 | seq_putc(m, '='); |
2069f457 EP |
1035 | if (has_comma) |
1036 | seq_putc(m, '\"'); | |
e3489f89 | 1037 | seq_escape(m, context, "\"\n\\"); |
2069f457 EP |
1038 | if (has_comma) |
1039 | seq_putc(m, '\"'); | |
1040 | } | |
e3489f89 AV |
1041 | kfree(context); |
1042 | return rc; | |
2069f457 EP |
1043 | } |
1044 | ||
1045 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1046 | { | |
e3489f89 | 1047 | struct superblock_security_struct *sbsec = sb->s_security; |
2069f457 EP |
1048 | int rc; |
1049 | ||
e3489f89 AV |
1050 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
1051 | return 0; | |
2069f457 | 1052 | |
65cddd50 | 1053 | if (!selinux_initialized(&selinux_state)) |
e3489f89 | 1054 | return 0; |
2069f457 | 1055 | |
e3489f89 AV |
1056 | if (sbsec->flags & FSCONTEXT_MNT) { |
1057 | seq_putc(m, ','); | |
1058 | seq_puts(m, FSCONTEXT_STR); | |
1059 | rc = show_sid(m, sbsec->sid); | |
1060 | if (rc) | |
1061 | return rc; | |
1062 | } | |
1063 | if (sbsec->flags & CONTEXT_MNT) { | |
1064 | seq_putc(m, ','); | |
1065 | seq_puts(m, CONTEXT_STR); | |
1066 | rc = show_sid(m, sbsec->mntpoint_sid); | |
1067 | if (rc) | |
1068 | return rc; | |
1069 | } | |
1070 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
1071 | seq_putc(m, ','); | |
1072 | seq_puts(m, DEFCONTEXT_STR); | |
1073 | rc = show_sid(m, sbsec->def_sid); | |
1074 | if (rc) | |
1075 | return rc; | |
1076 | } | |
1077 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
1078 | struct dentry *root = sbsec->sb->s_root; | |
1079 | struct inode_security_struct *isec = backing_inode_security(root); | |
1080 | seq_putc(m, ','); | |
1081 | seq_puts(m, ROOTCONTEXT_STR); | |
1082 | rc = show_sid(m, isec->sid); | |
1083 | if (rc) | |
1084 | return rc; | |
1085 | } | |
1086 | if (sbsec->flags & SBLABEL_MNT) { | |
1087 | seq_putc(m, ','); | |
442155c1 | 1088 | seq_puts(m, SECLABEL_STR); |
e3489f89 AV |
1089 | } |
1090 | return 0; | |
2069f457 EP |
1091 | } |
1092 | ||
1da177e4 LT |
1093 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1094 | { | |
1095 | switch (mode & S_IFMT) { | |
1096 | case S_IFSOCK: | |
1097 | return SECCLASS_SOCK_FILE; | |
1098 | case S_IFLNK: | |
1099 | return SECCLASS_LNK_FILE; | |
1100 | case S_IFREG: | |
1101 | return SECCLASS_FILE; | |
1102 | case S_IFBLK: | |
1103 | return SECCLASS_BLK_FILE; | |
1104 | case S_IFDIR: | |
1105 | return SECCLASS_DIR; | |
1106 | case S_IFCHR: | |
1107 | return SECCLASS_CHR_FILE; | |
1108 | case S_IFIFO: | |
1109 | return SECCLASS_FIFO_FILE; | |
1110 | ||
1111 | } | |
1112 | ||
1113 | return SECCLASS_FILE; | |
1114 | } | |
1115 | ||
13402580 JM |
1116 | static inline int default_protocol_stream(int protocol) |
1117 | { | |
1118 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1119 | } | |
1120 | ||
1121 | static inline int default_protocol_dgram(int protocol) | |
1122 | { | |
1123 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1124 | } | |
1125 | ||
1da177e4 LT |
1126 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1127 | { | |
aa8e712c | 1128 | int extsockclass = selinux_policycap_extsockclass(); |
da69a530 | 1129 | |
1da177e4 LT |
1130 | switch (family) { |
1131 | case PF_UNIX: | |
1132 | switch (type) { | |
1133 | case SOCK_STREAM: | |
1134 | case SOCK_SEQPACKET: | |
1135 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1136 | case SOCK_DGRAM: | |
2a764b52 | 1137 | case SOCK_RAW: |
1da177e4 LT |
1138 | return SECCLASS_UNIX_DGRAM_SOCKET; |
1139 | } | |
1140 | break; | |
1141 | case PF_INET: | |
1142 | case PF_INET6: | |
1143 | switch (type) { | |
1144 | case SOCK_STREAM: | |
da69a530 | 1145 | case SOCK_SEQPACKET: |
13402580 JM |
1146 | if (default_protocol_stream(protocol)) |
1147 | return SECCLASS_TCP_SOCKET; | |
da69a530 SS |
1148 | else if (extsockclass && protocol == IPPROTO_SCTP) |
1149 | return SECCLASS_SCTP_SOCKET; | |
13402580 JM |
1150 | else |
1151 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1152 | case SOCK_DGRAM: |
13402580 JM |
1153 | if (default_protocol_dgram(protocol)) |
1154 | return SECCLASS_UDP_SOCKET; | |
ef37979a SS |
1155 | else if (extsockclass && (protocol == IPPROTO_ICMP || |
1156 | protocol == IPPROTO_ICMPV6)) | |
da69a530 | 1157 | return SECCLASS_ICMP_SOCKET; |
13402580 JM |
1158 | else |
1159 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1160 | case SOCK_DCCP: |
1161 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1162 | default: |
1da177e4 LT |
1163 | return SECCLASS_RAWIP_SOCKET; |
1164 | } | |
1165 | break; | |
1166 | case PF_NETLINK: | |
1167 | switch (protocol) { | |
1168 | case NETLINK_ROUTE: | |
1169 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
7f1fb60c | 1170 | case NETLINK_SOCK_DIAG: |
1da177e4 LT |
1171 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1172 | case NETLINK_NFLOG: | |
1173 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1174 | case NETLINK_XFRM: | |
1175 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1176 | case NETLINK_SELINUX: | |
1177 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
6c6d2e9b SS |
1178 | case NETLINK_ISCSI: |
1179 | return SECCLASS_NETLINK_ISCSI_SOCKET; | |
1da177e4 LT |
1180 | case NETLINK_AUDIT: |
1181 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
6c6d2e9b SS |
1182 | case NETLINK_FIB_LOOKUP: |
1183 | return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; | |
1184 | case NETLINK_CONNECTOR: | |
1185 | return SECCLASS_NETLINK_CONNECTOR_SOCKET; | |
1186 | case NETLINK_NETFILTER: | |
1187 | return SECCLASS_NETLINK_NETFILTER_SOCKET; | |
1da177e4 LT |
1188 | case NETLINK_DNRTMSG: |
1189 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1190 | case NETLINK_KOBJECT_UEVENT: |
1191 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
6c6d2e9b SS |
1192 | case NETLINK_GENERIC: |
1193 | return SECCLASS_NETLINK_GENERIC_SOCKET; | |
1194 | case NETLINK_SCSITRANSPORT: | |
1195 | return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; | |
1196 | case NETLINK_RDMA: | |
1197 | return SECCLASS_NETLINK_RDMA_SOCKET; | |
1198 | case NETLINK_CRYPTO: | |
1199 | return SECCLASS_NETLINK_CRYPTO_SOCKET; | |
1da177e4 LT |
1200 | default: |
1201 | return SECCLASS_NETLINK_SOCKET; | |
1202 | } | |
1203 | case PF_PACKET: | |
1204 | return SECCLASS_PACKET_SOCKET; | |
1205 | case PF_KEY: | |
1206 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1207 | case PF_APPLETALK: |
1208 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1209 | } |
1210 | ||
da69a530 SS |
1211 | if (extsockclass) { |
1212 | switch (family) { | |
1213 | case PF_AX25: | |
1214 | return SECCLASS_AX25_SOCKET; | |
1215 | case PF_IPX: | |
1216 | return SECCLASS_IPX_SOCKET; | |
1217 | case PF_NETROM: | |
1218 | return SECCLASS_NETROM_SOCKET; | |
da69a530 SS |
1219 | case PF_ATMPVC: |
1220 | return SECCLASS_ATMPVC_SOCKET; | |
1221 | case PF_X25: | |
1222 | return SECCLASS_X25_SOCKET; | |
1223 | case PF_ROSE: | |
1224 | return SECCLASS_ROSE_SOCKET; | |
1225 | case PF_DECnet: | |
1226 | return SECCLASS_DECNET_SOCKET; | |
1227 | case PF_ATMSVC: | |
1228 | return SECCLASS_ATMSVC_SOCKET; | |
1229 | case PF_RDS: | |
1230 | return SECCLASS_RDS_SOCKET; | |
1231 | case PF_IRDA: | |
1232 | return SECCLASS_IRDA_SOCKET; | |
1233 | case PF_PPPOX: | |
1234 | return SECCLASS_PPPOX_SOCKET; | |
1235 | case PF_LLC: | |
1236 | return SECCLASS_LLC_SOCKET; | |
da69a530 SS |
1237 | case PF_CAN: |
1238 | return SECCLASS_CAN_SOCKET; | |
1239 | case PF_TIPC: | |
1240 | return SECCLASS_TIPC_SOCKET; | |
1241 | case PF_BLUETOOTH: | |
1242 | return SECCLASS_BLUETOOTH_SOCKET; | |
1243 | case PF_IUCV: | |
1244 | return SECCLASS_IUCV_SOCKET; | |
1245 | case PF_RXRPC: | |
1246 | return SECCLASS_RXRPC_SOCKET; | |
1247 | case PF_ISDN: | |
1248 | return SECCLASS_ISDN_SOCKET; | |
1249 | case PF_PHONET: | |
1250 | return SECCLASS_PHONET_SOCKET; | |
1251 | case PF_IEEE802154: | |
1252 | return SECCLASS_IEEE802154_SOCKET; | |
1253 | case PF_CAIF: | |
1254 | return SECCLASS_CAIF_SOCKET; | |
1255 | case PF_ALG: | |
1256 | return SECCLASS_ALG_SOCKET; | |
1257 | case PF_NFC: | |
1258 | return SECCLASS_NFC_SOCKET; | |
1259 | case PF_VSOCK: | |
1260 | return SECCLASS_VSOCK_SOCKET; | |
1261 | case PF_KCM: | |
1262 | return SECCLASS_KCM_SOCKET; | |
1263 | case PF_QIPCRTR: | |
1264 | return SECCLASS_QIPCRTR_SOCKET; | |
3051bf36 LT |
1265 | case PF_SMC: |
1266 | return SECCLASS_SMC_SOCKET; | |
68e8b849 BT |
1267 | case PF_XDP: |
1268 | return SECCLASS_XDP_SOCKET; | |
1269 | #if PF_MAX > 45 | |
da69a530 SS |
1270 | #error New address family defined, please update this function. |
1271 | #endif | |
1272 | } | |
1273 | } | |
1274 | ||
1da177e4 LT |
1275 | return SECCLASS_SOCKET; |
1276 | } | |
1277 | ||
134509d5 SS |
1278 | static int selinux_genfs_get_sid(struct dentry *dentry, |
1279 | u16 tclass, | |
1280 | u16 flags, | |
1281 | u32 *sid) | |
1da177e4 | 1282 | { |
8e6c9693 | 1283 | int rc; |
fc64005c | 1284 | struct super_block *sb = dentry->d_sb; |
8e6c9693 | 1285 | char *buffer, *path; |
1da177e4 | 1286 | |
828dfe1d | 1287 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1288 | if (!buffer) |
1289 | return -ENOMEM; | |
1290 | ||
8e6c9693 LAG |
1291 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1292 | if (IS_ERR(path)) | |
1293 | rc = PTR_ERR(path); | |
1294 | else { | |
134509d5 SS |
1295 | if (flags & SE_SBPROC) { |
1296 | /* each process gets a /proc/PID/ entry. Strip off the | |
1297 | * PID part to get a valid selinux labeling. | |
1298 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1299 | while (path[1] >= '0' && path[1] <= '9') { | |
1300 | path[1] = '/'; | |
1301 | path++; | |
1302 | } | |
8e6c9693 | 1303 | } |
aa8e712c SS |
1304 | rc = security_genfs_sid(&selinux_state, sb->s_type->name, |
1305 | path, tclass, sid); | |
7bb185ed SS |
1306 | if (rc == -ENOENT) { |
1307 | /* No match in policy, mark as unlabeled. */ | |
1308 | *sid = SECINITSID_UNLABELED; | |
1309 | rc = 0; | |
1310 | } | |
1da177e4 | 1311 | } |
1da177e4 LT |
1312 | free_page((unsigned long)buffer); |
1313 | return rc; | |
1314 | } | |
1da177e4 | 1315 | |
b754026b OM |
1316 | static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, |
1317 | u32 def_sid, u32 *sid) | |
1318 | { | |
1319 | #define INITCONTEXTLEN 255 | |
1320 | char *context; | |
1321 | unsigned int len; | |
1322 | int rc; | |
1323 | ||
1324 | len = INITCONTEXTLEN; | |
1325 | context = kmalloc(len + 1, GFP_NOFS); | |
1326 | if (!context) | |
1327 | return -ENOMEM; | |
1328 | ||
1329 | context[len] = '\0'; | |
1330 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); | |
1331 | if (rc == -ERANGE) { | |
1332 | kfree(context); | |
1333 | ||
1334 | /* Need a larger buffer. Query for the right size. */ | |
1335 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); | |
1336 | if (rc < 0) | |
1337 | return rc; | |
1338 | ||
1339 | len = rc; | |
1340 | context = kmalloc(len + 1, GFP_NOFS); | |
1341 | if (!context) | |
1342 | return -ENOMEM; | |
1343 | ||
1344 | context[len] = '\0'; | |
1345 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, | |
1346 | context, len); | |
1347 | } | |
1348 | if (rc < 0) { | |
1349 | kfree(context); | |
1350 | if (rc != -ENODATA) { | |
1351 | pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", | |
1352 | __func__, -rc, inode->i_sb->s_id, inode->i_ino); | |
1353 | return rc; | |
1354 | } | |
1355 | *sid = def_sid; | |
1356 | return 0; | |
1357 | } | |
1358 | ||
1359 | rc = security_context_to_sid_default(&selinux_state, context, rc, sid, | |
1360 | def_sid, GFP_NOFS); | |
1361 | if (rc) { | |
1362 | char *dev = inode->i_sb->s_id; | |
1363 | unsigned long ino = inode->i_ino; | |
1364 | ||
1365 | if (rc == -EINVAL) { | |
1366 | 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", | |
1367 | ino, dev, context); | |
1368 | } else { | |
1369 | pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", | |
1370 | __func__, context, -rc, dev, ino); | |
1371 | } | |
1372 | } | |
1373 | kfree(context); | |
1374 | return 0; | |
1375 | } | |
1376 | ||
1da177e4 LT |
1377 | /* The inode's security attributes must be initialized before first use. */ |
1378 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1379 | { | |
1380 | struct superblock_security_struct *sbsec = NULL; | |
80788c22 | 1381 | struct inode_security_struct *isec = selinux_inode(inode); |
9287aed2 AG |
1382 | u32 task_sid, sid = 0; |
1383 | u16 sclass; | |
1da177e4 | 1384 | struct dentry *dentry; |
1da177e4 | 1385 | int rc = 0; |
1da177e4 | 1386 | |
6f3be9f5 | 1387 | if (isec->initialized == LABEL_INITIALIZED) |
13457d07 | 1388 | return 0; |
1da177e4 | 1389 | |
9287aed2 | 1390 | spin_lock(&isec->lock); |
6f3be9f5 | 1391 | if (isec->initialized == LABEL_INITIALIZED) |
23970741 | 1392 | goto out_unlock; |
1da177e4 | 1393 | |
13457d07 AG |
1394 | if (isec->sclass == SECCLASS_FILE) |
1395 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1396 | ||
1da177e4 | 1397 | sbsec = inode->i_sb->s_security; |
0d90a7ec | 1398 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1399 | /* Defer initialization until selinux_complete_init, |
1400 | after the initial policy is loaded and the security | |
1401 | server is ready to handle calls. */ | |
1402 | spin_lock(&sbsec->isec_lock); | |
1403 | if (list_empty(&isec->list)) | |
1404 | list_add(&isec->list, &sbsec->isec_head); | |
1405 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1406 | goto out_unlock; |
1da177e4 LT |
1407 | } |
1408 | ||
9287aed2 AG |
1409 | sclass = isec->sclass; |
1410 | task_sid = isec->task_sid; | |
1411 | sid = isec->sid; | |
1412 | isec->initialized = LABEL_PENDING; | |
1413 | spin_unlock(&isec->lock); | |
1414 | ||
1da177e4 | 1415 | switch (sbsec->behavior) { |
eb9ae686 DQ |
1416 | case SECURITY_FS_USE_NATIVE: |
1417 | break; | |
1da177e4 | 1418 | case SECURITY_FS_USE_XATTR: |
5d6c3191 | 1419 | if (!(inode->i_opflags & IOP_XATTR)) { |
9287aed2 | 1420 | sid = sbsec->def_sid; |
1da177e4 LT |
1421 | break; |
1422 | } | |
1da177e4 LT |
1423 | /* Need a dentry, since the xattr API requires one. |
1424 | Life would be simpler if we could just pass the inode. */ | |
1425 | if (opt_dentry) { | |
1426 | /* Called from d_instantiate or d_splice_alias. */ | |
1427 | dentry = dget(opt_dentry); | |
1428 | } else { | |
b127125d AV |
1429 | /* |
1430 | * Called from selinux_complete_init, try to find a dentry. | |
1431 | * Some filesystems really want a connected one, so try | |
1432 | * that first. We could split SECURITY_FS_USE_XATTR in | |
1433 | * two, depending upon that... | |
1434 | */ | |
1da177e4 | 1435 | dentry = d_find_alias(inode); |
b127125d AV |
1436 | if (!dentry) |
1437 | dentry = d_find_any_alias(inode); | |
1da177e4 LT |
1438 | } |
1439 | if (!dentry) { | |
df7f54c0 EP |
1440 | /* |
1441 | * this is can be hit on boot when a file is accessed | |
1442 | * before the policy is loaded. When we load policy we | |
1443 | * may find inodes that have no dentry on the | |
1444 | * sbsec->isec_head list. No reason to complain as these | |
1445 | * will get fixed up the next time we go through | |
1446 | * inode_doinit with a dentry, before these inodes could | |
1447 | * be used again by userspace. | |
1448 | */ | |
9287aed2 | 1449 | goto out; |
1da177e4 LT |
1450 | } |
1451 | ||
b754026b OM |
1452 | rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, |
1453 | &sid); | |
1da177e4 | 1454 | dput(dentry); |
b754026b OM |
1455 | if (rc) |
1456 | goto out; | |
1da177e4 LT |
1457 | break; |
1458 | case SECURITY_FS_USE_TASK: | |
9287aed2 | 1459 | sid = task_sid; |
1da177e4 LT |
1460 | break; |
1461 | case SECURITY_FS_USE_TRANS: | |
1462 | /* Default to the fs SID. */ | |
9287aed2 | 1463 | sid = sbsec->sid; |
1da177e4 LT |
1464 | |
1465 | /* Try to obtain a transition SID. */ | |
aa8e712c SS |
1466 | rc = security_transition_sid(&selinux_state, task_sid, sid, |
1467 | sclass, NULL, &sid); | |
1da177e4 | 1468 | if (rc) |
9287aed2 | 1469 | goto out; |
1da177e4 | 1470 | break; |
c312feb2 | 1471 | case SECURITY_FS_USE_MNTPOINT: |
9287aed2 | 1472 | sid = sbsec->mntpoint_sid; |
c312feb2 | 1473 | break; |
1da177e4 | 1474 | default: |
c312feb2 | 1475 | /* Default to the fs superblock SID. */ |
9287aed2 | 1476 | sid = sbsec->sid; |
1da177e4 | 1477 | |
134509d5 | 1478 | if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) { |
f64410ec PM |
1479 | /* We must have a dentry to determine the label on |
1480 | * procfs inodes */ | |
b127125d | 1481 | if (opt_dentry) { |
f64410ec PM |
1482 | /* Called from d_instantiate or |
1483 | * d_splice_alias. */ | |
1484 | dentry = dget(opt_dentry); | |
b127125d | 1485 | } else { |
f64410ec | 1486 | /* Called from selinux_complete_init, try to |
b127125d AV |
1487 | * find a dentry. Some filesystems really want |
1488 | * a connected one, so try that first. | |
1489 | */ | |
f64410ec | 1490 | dentry = d_find_alias(inode); |
b127125d AV |
1491 | if (!dentry) |
1492 | dentry = d_find_any_alias(inode); | |
1493 | } | |
f64410ec PM |
1494 | /* |
1495 | * This can be hit on boot when a file is accessed | |
1496 | * before the policy is loaded. When we load policy we | |
1497 | * may find inodes that have no dentry on the | |
1498 | * sbsec->isec_head list. No reason to complain as | |
1499 | * these will get fixed up the next time we go through | |
1500 | * inode_doinit() with a dentry, before these inodes | |
1501 | * could be used again by userspace. | |
1502 | */ | |
1503 | if (!dentry) | |
9287aed2 AG |
1504 | goto out; |
1505 | rc = selinux_genfs_get_sid(dentry, sclass, | |
134509d5 | 1506 | sbsec->flags, &sid); |
b754026b OM |
1507 | if (rc) { |
1508 | dput(dentry); | |
9287aed2 | 1509 | goto out; |
b754026b OM |
1510 | } |
1511 | ||
1512 | if ((sbsec->flags & SE_SBGENFS_XATTR) && | |
1513 | (inode->i_opflags & IOP_XATTR)) { | |
1514 | rc = inode_doinit_use_xattr(inode, dentry, | |
1515 | sid, &sid); | |
1516 | if (rc) { | |
1517 | dput(dentry); | |
1518 | goto out; | |
1519 | } | |
1520 | } | |
1521 | dput(dentry); | |
1da177e4 LT |
1522 | } |
1523 | break; | |
1524 | } | |
1525 | ||
9287aed2 AG |
1526 | out: |
1527 | spin_lock(&isec->lock); | |
1528 | if (isec->initialized == LABEL_PENDING) { | |
1529 | if (!sid || rc) { | |
1530 | isec->initialized = LABEL_INVALID; | |
1531 | goto out_unlock; | |
1532 | } | |
1533 | ||
1534 | isec->initialized = LABEL_INITIALIZED; | |
1535 | isec->sid = sid; | |
1536 | } | |
1da177e4 | 1537 | |
23970741 | 1538 | out_unlock: |
9287aed2 | 1539 | spin_unlock(&isec->lock); |
1da177e4 LT |
1540 | return rc; |
1541 | } | |
1542 | ||
1543 | /* Convert a Linux signal to an access vector. */ | |
1544 | static inline u32 signal_to_av(int sig) | |
1545 | { | |
1546 | u32 perm = 0; | |
1547 | ||
1548 | switch (sig) { | |
1549 | case SIGCHLD: | |
1550 | /* Commonly granted from child to parent. */ | |
1551 | perm = PROCESS__SIGCHLD; | |
1552 | break; | |
1553 | case SIGKILL: | |
1554 | /* Cannot be caught or ignored */ | |
1555 | perm = PROCESS__SIGKILL; | |
1556 | break; | |
1557 | case SIGSTOP: | |
1558 | /* Cannot be caught or ignored */ | |
1559 | perm = PROCESS__SIGSTOP; | |
1560 | break; | |
1561 | default: | |
1562 | /* All other signals. */ | |
1563 | perm = PROCESS__SIGNAL; | |
1564 | break; | |
1565 | } | |
1566 | ||
1567 | return perm; | |
1568 | } | |
1569 | ||
b68e418c SS |
1570 | #if CAP_LAST_CAP > 63 |
1571 | #error Fix SELinux to handle capabilities > 63. | |
1572 | #endif | |
1573 | ||
1da177e4 | 1574 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1575 | static int cred_has_capability(const struct cred *cred, |
c1a85a00 | 1576 | int cap, unsigned int opts, bool initns) |
1da177e4 | 1577 | { |
2bf49690 | 1578 | struct common_audit_data ad; |
06112163 | 1579 | struct av_decision avd; |
b68e418c | 1580 | u16 sclass; |
3699c53c | 1581 | u32 sid = cred_sid(cred); |
b68e418c | 1582 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1583 | int rc; |
1da177e4 | 1584 | |
50c205f5 | 1585 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1586 | ad.u.cap = cap; |
1587 | ||
b68e418c SS |
1588 | switch (CAP_TO_INDEX(cap)) { |
1589 | case 0: | |
8e4ff6f2 | 1590 | sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; |
b68e418c SS |
1591 | break; |
1592 | case 1: | |
8e4ff6f2 | 1593 | sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; |
b68e418c SS |
1594 | break; |
1595 | default: | |
c103a91e | 1596 | pr_err("SELinux: out of range capability %d\n", cap); |
b68e418c | 1597 | BUG(); |
a35c6c83 | 1598 | return -EINVAL; |
b68e418c | 1599 | } |
06112163 | 1600 | |
6b6bc620 SS |
1601 | rc = avc_has_perm_noaudit(&selinux_state, |
1602 | sid, sid, sclass, av, 0, &avd); | |
c1a85a00 | 1603 | if (!(opts & CAP_OPT_NOAUDIT)) { |
6b6bc620 SS |
1604 | int rc2 = avc_audit(&selinux_state, |
1605 | sid, sid, sclass, av, &avd, rc, &ad, 0); | |
9ade0cf4 EP |
1606 | if (rc2) |
1607 | return rc2; | |
1608 | } | |
06112163 | 1609 | return rc; |
1da177e4 LT |
1610 | } |
1611 | ||
1da177e4 LT |
1612 | /* Check whether a task has a particular permission to an inode. |
1613 | The 'adp' parameter is optional and allows other audit | |
1614 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1615 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1616 | struct inode *inode, |
1617 | u32 perms, | |
19e49834 | 1618 | struct common_audit_data *adp) |
1da177e4 | 1619 | { |
1da177e4 | 1620 | struct inode_security_struct *isec; |
275bb41e | 1621 | u32 sid; |
1da177e4 | 1622 | |
e0e81739 DH |
1623 | validate_creds(cred); |
1624 | ||
828dfe1d | 1625 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1626 | return 0; |
1627 | ||
88e67f3b | 1628 | sid = cred_sid(cred); |
80788c22 | 1629 | isec = selinux_inode(inode); |
1da177e4 | 1630 | |
6b6bc620 SS |
1631 | return avc_has_perm(&selinux_state, |
1632 | sid, isec->sid, isec->sclass, perms, adp); | |
1da177e4 LT |
1633 | } |
1634 | ||
1635 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1636 | the dentry to help the auditing code to more easily generate the | |
1637 | pathname if needed. */ | |
88e67f3b | 1638 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1639 | struct dentry *dentry, |
1640 | u32 av) | |
1641 | { | |
c6f493d6 | 1642 | struct inode *inode = d_backing_inode(dentry); |
2bf49690 | 1643 | struct common_audit_data ad; |
88e67f3b | 1644 | |
50c205f5 | 1645 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1646 | ad.u.dentry = dentry; |
5d226df4 | 1647 | __inode_security_revalidate(inode, dentry, true); |
19e49834 | 1648 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1649 | } |
1650 | ||
1651 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1652 | the path to help the auditing code to more easily generate the | |
1653 | pathname if needed. */ | |
1654 | static inline int path_has_perm(const struct cred *cred, | |
3f7036a0 | 1655 | const struct path *path, |
2875fa00 EP |
1656 | u32 av) |
1657 | { | |
c6f493d6 | 1658 | struct inode *inode = d_backing_inode(path->dentry); |
2875fa00 EP |
1659 | struct common_audit_data ad; |
1660 | ||
50c205f5 | 1661 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1662 | ad.u.path = *path; |
5d226df4 | 1663 | __inode_security_revalidate(inode, path->dentry, true); |
19e49834 | 1664 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1665 | } |
1666 | ||
13f8e981 DH |
1667 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1668 | static inline int file_path_has_perm(const struct cred *cred, | |
1669 | struct file *file, | |
1670 | u32 av) | |
1671 | { | |
1672 | struct common_audit_data ad; | |
1673 | ||
43af5de7 VG |
1674 | ad.type = LSM_AUDIT_DATA_FILE; |
1675 | ad.u.file = file; | |
19e49834 | 1676 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1677 | } |
1678 | ||
f66e448c CF |
1679 | #ifdef CONFIG_BPF_SYSCALL |
1680 | static int bpf_fd_pass(struct file *file, u32 sid); | |
1681 | #endif | |
1682 | ||
1da177e4 LT |
1683 | /* Check whether a task can use an open file descriptor to |
1684 | access an inode in a given way. Check access to the | |
1685 | descriptor itself, and then use dentry_has_perm to | |
1686 | check a particular permission to the file. | |
1687 | Access to the descriptor is implicitly granted if it | |
1688 | has the same SID as the process. If av is zero, then | |
1689 | access to the file is not checked, e.g. for cases | |
1690 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1691 | static int file_has_perm(const struct cred *cred, |
1692 | struct file *file, | |
1693 | u32 av) | |
1da177e4 | 1694 | { |
bb6c6b02 | 1695 | struct file_security_struct *fsec = selinux_file(file); |
496ad9aa | 1696 | struct inode *inode = file_inode(file); |
2bf49690 | 1697 | struct common_audit_data ad; |
88e67f3b | 1698 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1699 | int rc; |
1700 | ||
43af5de7 VG |
1701 | ad.type = LSM_AUDIT_DATA_FILE; |
1702 | ad.u.file = file; | |
1da177e4 | 1703 | |
275bb41e | 1704 | if (sid != fsec->sid) { |
6b6bc620 SS |
1705 | rc = avc_has_perm(&selinux_state, |
1706 | sid, fsec->sid, | |
1da177e4 LT |
1707 | SECCLASS_FD, |
1708 | FD__USE, | |
1709 | &ad); | |
1710 | if (rc) | |
88e67f3b | 1711 | goto out; |
1da177e4 LT |
1712 | } |
1713 | ||
f66e448c CF |
1714 | #ifdef CONFIG_BPF_SYSCALL |
1715 | rc = bpf_fd_pass(file, cred_sid(cred)); | |
1716 | if (rc) | |
1717 | return rc; | |
1718 | #endif | |
1719 | ||
1da177e4 | 1720 | /* av is zero if only checking access to the descriptor. */ |
88e67f3b | 1721 | rc = 0; |
1da177e4 | 1722 | if (av) |
19e49834 | 1723 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1724 | |
88e67f3b DH |
1725 | out: |
1726 | return rc; | |
1da177e4 LT |
1727 | } |
1728 | ||
c3c188b2 DH |
1729 | /* |
1730 | * Determine the label for an inode that might be unioned. | |
1731 | */ | |
c957f6df VG |
1732 | static int |
1733 | selinux_determine_inode_label(const struct task_security_struct *tsec, | |
1734 | struct inode *dir, | |
1735 | const struct qstr *name, u16 tclass, | |
1736 | u32 *_new_isid) | |
c3c188b2 DH |
1737 | { |
1738 | const struct superblock_security_struct *sbsec = dir->i_sb->s_security; | |
c3c188b2 DH |
1739 | |
1740 | if ((sbsec->flags & SE_SBINITIALIZED) && | |
1741 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { | |
1742 | *_new_isid = sbsec->mntpoint_sid; | |
1743 | } else if ((sbsec->flags & SBLABEL_MNT) && | |
1744 | tsec->create_sid) { | |
1745 | *_new_isid = tsec->create_sid; | |
1746 | } else { | |
20cdef8d | 1747 | const struct inode_security_struct *dsec = inode_security(dir); |
aa8e712c SS |
1748 | return security_transition_sid(&selinux_state, tsec->sid, |
1749 | dsec->sid, tclass, | |
c3c188b2 DH |
1750 | name, _new_isid); |
1751 | } | |
1752 | ||
1753 | return 0; | |
1754 | } | |
1755 | ||
1da177e4 LT |
1756 | /* Check whether a task can create a file. */ |
1757 | static int may_create(struct inode *dir, | |
1758 | struct dentry *dentry, | |
1759 | u16 tclass) | |
1760 | { | |
0c6cfa62 | 1761 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
1da177e4 LT |
1762 | struct inode_security_struct *dsec; |
1763 | struct superblock_security_struct *sbsec; | |
275bb41e | 1764 | u32 sid, newsid; |
2bf49690 | 1765 | struct common_audit_data ad; |
1da177e4 LT |
1766 | int rc; |
1767 | ||
83da53c5 | 1768 | dsec = inode_security(dir); |
1da177e4 LT |
1769 | sbsec = dir->i_sb->s_security; |
1770 | ||
275bb41e | 1771 | sid = tsec->sid; |
275bb41e | 1772 | |
50c205f5 | 1773 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1774 | ad.u.dentry = dentry; |
1da177e4 | 1775 | |
6b6bc620 SS |
1776 | rc = avc_has_perm(&selinux_state, |
1777 | sid, dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
1778 | DIR__ADD_NAME | DIR__SEARCH, |
1779 | &ad); | |
1780 | if (rc) | |
1781 | return rc; | |
1782 | ||
210a2928 YG |
1783 | rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, |
1784 | &newsid); | |
c3c188b2 DH |
1785 | if (rc) |
1786 | return rc; | |
1da177e4 | 1787 | |
6b6bc620 SS |
1788 | rc = avc_has_perm(&selinux_state, |
1789 | sid, newsid, tclass, FILE__CREATE, &ad); | |
1da177e4 LT |
1790 | if (rc) |
1791 | return rc; | |
1792 | ||
6b6bc620 SS |
1793 | return avc_has_perm(&selinux_state, |
1794 | newsid, sbsec->sid, | |
1da177e4 LT |
1795 | SECCLASS_FILESYSTEM, |
1796 | FILESYSTEM__ASSOCIATE, &ad); | |
1797 | } | |
1798 | ||
828dfe1d EP |
1799 | #define MAY_LINK 0 |
1800 | #define MAY_UNLINK 1 | |
1801 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1802 | |
1803 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1804 | static int may_link(struct inode *dir, | |
1805 | struct dentry *dentry, | |
1806 | int kind) | |
1807 | ||
1808 | { | |
1da177e4 | 1809 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 1810 | struct common_audit_data ad; |
275bb41e | 1811 | u32 sid = current_sid(); |
1da177e4 LT |
1812 | u32 av; |
1813 | int rc; | |
1814 | ||
83da53c5 AG |
1815 | dsec = inode_security(dir); |
1816 | isec = backing_inode_security(dentry); | |
1da177e4 | 1817 | |
50c205f5 | 1818 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1819 | ad.u.dentry = dentry; |
1da177e4 LT |
1820 | |
1821 | av = DIR__SEARCH; | |
1822 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
6b6bc620 SS |
1823 | rc = avc_has_perm(&selinux_state, |
1824 | sid, dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
1825 | if (rc) |
1826 | return rc; | |
1827 | ||
1828 | switch (kind) { | |
1829 | case MAY_LINK: | |
1830 | av = FILE__LINK; | |
1831 | break; | |
1832 | case MAY_UNLINK: | |
1833 | av = FILE__UNLINK; | |
1834 | break; | |
1835 | case MAY_RMDIR: | |
1836 | av = DIR__RMDIR; | |
1837 | break; | |
1838 | default: | |
c103a91e | 1839 | pr_warn("SELinux: %s: unrecognized kind %d\n", |
744ba35e | 1840 | __func__, kind); |
1da177e4 LT |
1841 | return 0; |
1842 | } | |
1843 | ||
6b6bc620 SS |
1844 | rc = avc_has_perm(&selinux_state, |
1845 | sid, isec->sid, isec->sclass, av, &ad); | |
1da177e4 LT |
1846 | return rc; |
1847 | } | |
1848 | ||
1849 | static inline int may_rename(struct inode *old_dir, | |
1850 | struct dentry *old_dentry, | |
1851 | struct inode *new_dir, | |
1852 | struct dentry *new_dentry) | |
1853 | { | |
1da177e4 | 1854 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 1855 | struct common_audit_data ad; |
275bb41e | 1856 | u32 sid = current_sid(); |
1da177e4 LT |
1857 | u32 av; |
1858 | int old_is_dir, new_is_dir; | |
1859 | int rc; | |
1860 | ||
83da53c5 AG |
1861 | old_dsec = inode_security(old_dir); |
1862 | old_isec = backing_inode_security(old_dentry); | |
e36cb0b8 | 1863 | old_is_dir = d_is_dir(old_dentry); |
83da53c5 | 1864 | new_dsec = inode_security(new_dir); |
1da177e4 | 1865 | |
50c205f5 | 1866 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 1867 | |
a269434d | 1868 | ad.u.dentry = old_dentry; |
6b6bc620 SS |
1869 | rc = avc_has_perm(&selinux_state, |
1870 | sid, old_dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
1871 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
1872 | if (rc) | |
1873 | return rc; | |
6b6bc620 SS |
1874 | rc = avc_has_perm(&selinux_state, |
1875 | sid, old_isec->sid, | |
1da177e4 LT |
1876 | old_isec->sclass, FILE__RENAME, &ad); |
1877 | if (rc) | |
1878 | return rc; | |
1879 | if (old_is_dir && new_dir != old_dir) { | |
6b6bc620 SS |
1880 | rc = avc_has_perm(&selinux_state, |
1881 | sid, old_isec->sid, | |
1da177e4 LT |
1882 | old_isec->sclass, DIR__REPARENT, &ad); |
1883 | if (rc) | |
1884 | return rc; | |
1885 | } | |
1886 | ||
a269434d | 1887 | ad.u.dentry = new_dentry; |
1da177e4 | 1888 | av = DIR__ADD_NAME | DIR__SEARCH; |
2c616d4d | 1889 | if (d_is_positive(new_dentry)) |
1da177e4 | 1890 | av |= DIR__REMOVE_NAME; |
6b6bc620 SS |
1891 | rc = avc_has_perm(&selinux_state, |
1892 | sid, new_dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
1893 | if (rc) |
1894 | return rc; | |
2c616d4d | 1895 | if (d_is_positive(new_dentry)) { |
83da53c5 | 1896 | new_isec = backing_inode_security(new_dentry); |
e36cb0b8 | 1897 | new_is_dir = d_is_dir(new_dentry); |
6b6bc620 SS |
1898 | rc = avc_has_perm(&selinux_state, |
1899 | sid, new_isec->sid, | |
1da177e4 LT |
1900 | new_isec->sclass, |
1901 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1902 | if (rc) | |
1903 | return rc; | |
1904 | } | |
1905 | ||
1906 | return 0; | |
1907 | } | |
1908 | ||
1909 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 1910 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
1911 | struct super_block *sb, |
1912 | u32 perms, | |
2bf49690 | 1913 | struct common_audit_data *ad) |
1da177e4 | 1914 | { |
1da177e4 | 1915 | struct superblock_security_struct *sbsec; |
88e67f3b | 1916 | u32 sid = cred_sid(cred); |
1da177e4 | 1917 | |
1da177e4 | 1918 | sbsec = sb->s_security; |
6b6bc620 SS |
1919 | return avc_has_perm(&selinux_state, |
1920 | sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); | |
1da177e4 LT |
1921 | } |
1922 | ||
1923 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1924 | static inline u32 file_mask_to_av(int mode, int mask) | |
1925 | { | |
1926 | u32 av = 0; | |
1927 | ||
dba19c60 | 1928 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
1929 | if (mask & MAY_EXEC) |
1930 | av |= FILE__EXECUTE; | |
1931 | if (mask & MAY_READ) | |
1932 | av |= FILE__READ; | |
1933 | ||
1934 | if (mask & MAY_APPEND) | |
1935 | av |= FILE__APPEND; | |
1936 | else if (mask & MAY_WRITE) | |
1937 | av |= FILE__WRITE; | |
1938 | ||
1939 | } else { | |
1940 | if (mask & MAY_EXEC) | |
1941 | av |= DIR__SEARCH; | |
1942 | if (mask & MAY_WRITE) | |
1943 | av |= DIR__WRITE; | |
1944 | if (mask & MAY_READ) | |
1945 | av |= DIR__READ; | |
1946 | } | |
1947 | ||
1948 | return av; | |
1949 | } | |
1950 | ||
8b6a5a37 EP |
1951 | /* Convert a Linux file to an access vector. */ |
1952 | static inline u32 file_to_av(struct file *file) | |
1953 | { | |
1954 | u32 av = 0; | |
1955 | ||
1956 | if (file->f_mode & FMODE_READ) | |
1957 | av |= FILE__READ; | |
1958 | if (file->f_mode & FMODE_WRITE) { | |
1959 | if (file->f_flags & O_APPEND) | |
1960 | av |= FILE__APPEND; | |
1961 | else | |
1962 | av |= FILE__WRITE; | |
1963 | } | |
1964 | if (!av) { | |
1965 | /* | |
1966 | * Special file opened with flags 3 for ioctl-only use. | |
1967 | */ | |
1968 | av = FILE__IOCTL; | |
1969 | } | |
1970 | ||
1971 | return av; | |
1972 | } | |
1973 | ||
b0c636b9 | 1974 | /* |
8b6a5a37 | 1975 | * Convert a file to an access vector and include the correct open |
b0c636b9 EP |
1976 | * open permission. |
1977 | */ | |
8b6a5a37 | 1978 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 1979 | { |
8b6a5a37 | 1980 | u32 av = file_to_av(file); |
ccb54478 | 1981 | struct inode *inode = file_inode(file); |
b0c636b9 | 1982 | |
aa8e712c SS |
1983 | if (selinux_policycap_openperm() && |
1984 | inode->i_sb->s_magic != SOCKFS_MAGIC) | |
49b7b8de EP |
1985 | av |= FILE__OPEN; |
1986 | ||
b0c636b9 EP |
1987 | return av; |
1988 | } | |
1989 | ||
1da177e4 LT |
1990 | /* Hook functions begin here. */ |
1991 | ||
79af7307 SS |
1992 | static int selinux_binder_set_context_mgr(struct task_struct *mgr) |
1993 | { | |
1994 | u32 mysid = current_sid(); | |
1995 | u32 mgrsid = task_sid(mgr); | |
1996 | ||
6b6bc620 SS |
1997 | return avc_has_perm(&selinux_state, |
1998 | mysid, mgrsid, SECCLASS_BINDER, | |
79af7307 SS |
1999 | BINDER__SET_CONTEXT_MGR, NULL); |
2000 | } | |
2001 | ||
2002 | static int selinux_binder_transaction(struct task_struct *from, | |
2003 | struct task_struct *to) | |
2004 | { | |
2005 | u32 mysid = current_sid(); | |
2006 | u32 fromsid = task_sid(from); | |
2007 | u32 tosid = task_sid(to); | |
2008 | int rc; | |
2009 | ||
2010 | if (mysid != fromsid) { | |
6b6bc620 SS |
2011 | rc = avc_has_perm(&selinux_state, |
2012 | mysid, fromsid, SECCLASS_BINDER, | |
79af7307 SS |
2013 | BINDER__IMPERSONATE, NULL); |
2014 | if (rc) | |
2015 | return rc; | |
2016 | } | |
2017 | ||
6b6bc620 SS |
2018 | return avc_has_perm(&selinux_state, |
2019 | fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, | |
79af7307 SS |
2020 | NULL); |
2021 | } | |
2022 | ||
2023 | static int selinux_binder_transfer_binder(struct task_struct *from, | |
2024 | struct task_struct *to) | |
2025 | { | |
2026 | u32 fromsid = task_sid(from); | |
2027 | u32 tosid = task_sid(to); | |
2028 | ||
6b6bc620 SS |
2029 | return avc_has_perm(&selinux_state, |
2030 | fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, | |
79af7307 SS |
2031 | NULL); |
2032 | } | |
2033 | ||
2034 | static int selinux_binder_transfer_file(struct task_struct *from, | |
2035 | struct task_struct *to, | |
2036 | struct file *file) | |
2037 | { | |
2038 | u32 sid = task_sid(to); | |
bb6c6b02 | 2039 | struct file_security_struct *fsec = selinux_file(file); |
83da53c5 | 2040 | struct dentry *dentry = file->f_path.dentry; |
20cdef8d | 2041 | struct inode_security_struct *isec; |
79af7307 SS |
2042 | struct common_audit_data ad; |
2043 | int rc; | |
2044 | ||
2045 | ad.type = LSM_AUDIT_DATA_PATH; | |
2046 | ad.u.path = file->f_path; | |
2047 | ||
2048 | if (sid != fsec->sid) { | |
6b6bc620 SS |
2049 | rc = avc_has_perm(&selinux_state, |
2050 | sid, fsec->sid, | |
79af7307 SS |
2051 | SECCLASS_FD, |
2052 | FD__USE, | |
2053 | &ad); | |
2054 | if (rc) | |
2055 | return rc; | |
2056 | } | |
2057 | ||
f66e448c CF |
2058 | #ifdef CONFIG_BPF_SYSCALL |
2059 | rc = bpf_fd_pass(file, sid); | |
2060 | if (rc) | |
2061 | return rc; | |
2062 | #endif | |
2063 | ||
83da53c5 | 2064 | if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
79af7307 SS |
2065 | return 0; |
2066 | ||
20cdef8d | 2067 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
2068 | return avc_has_perm(&selinux_state, |
2069 | sid, isec->sid, isec->sclass, file_to_av(file), | |
79af7307 SS |
2070 | &ad); |
2071 | } | |
2072 | ||
9e48858f | 2073 | static int selinux_ptrace_access_check(struct task_struct *child, |
5cd9c58f | 2074 | unsigned int mode) |
1da177e4 | 2075 | { |
be0554c9 SS |
2076 | u32 sid = current_sid(); |
2077 | u32 csid = task_sid(child); | |
2078 | ||
2079 | if (mode & PTRACE_MODE_READ) | |
6b6bc620 SS |
2080 | return avc_has_perm(&selinux_state, |
2081 | sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 | 2082 | |
6b6bc620 SS |
2083 | return avc_has_perm(&selinux_state, |
2084 | sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); | |
5cd9c58f DH |
2085 | } |
2086 | ||
2087 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
2088 | { | |
6b6bc620 SS |
2089 | return avc_has_perm(&selinux_state, |
2090 | task_sid(parent), current_sid(), SECCLASS_PROCESS, | |
be0554c9 | 2091 | PROCESS__PTRACE, NULL); |
1da177e4 LT |
2092 | } |
2093 | ||
2094 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 2095 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 | 2096 | { |
6b6bc620 SS |
2097 | return avc_has_perm(&selinux_state, |
2098 | current_sid(), task_sid(target), SECCLASS_PROCESS, | |
be0554c9 | 2099 | PROCESS__GETCAP, NULL); |
1da177e4 LT |
2100 | } |
2101 | ||
d84f4f99 DH |
2102 | static int selinux_capset(struct cred *new, const struct cred *old, |
2103 | const kernel_cap_t *effective, | |
2104 | const kernel_cap_t *inheritable, | |
2105 | const kernel_cap_t *permitted) | |
1da177e4 | 2106 | { |
6b6bc620 SS |
2107 | return avc_has_perm(&selinux_state, |
2108 | cred_sid(old), cred_sid(new), SECCLASS_PROCESS, | |
be0554c9 | 2109 | PROCESS__SETCAP, NULL); |
1da177e4 LT |
2110 | } |
2111 | ||
5626d3e8 JM |
2112 | /* |
2113 | * (This comment used to live with the selinux_task_setuid hook, | |
2114 | * which was removed). | |
2115 | * | |
2116 | * Since setuid only affects the current process, and since the SELinux | |
2117 | * controls are not based on the Linux identity attributes, SELinux does not | |
2118 | * need to control this operation. However, SELinux does control the use of | |
2119 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
2120 | */ | |
2121 | ||
6a9de491 | 2122 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
c1a85a00 | 2123 | int cap, unsigned int opts) |
1da177e4 | 2124 | { |
c1a85a00 | 2125 | return cred_has_capability(cred, cap, opts, ns == &init_user_ns); |
1da177e4 LT |
2126 | } |
2127 | ||
1da177e4 LT |
2128 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
2129 | { | |
88e67f3b | 2130 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2131 | int rc = 0; |
2132 | ||
2133 | if (!sb) | |
2134 | return 0; | |
2135 | ||
2136 | switch (cmds) { | |
828dfe1d EP |
2137 | case Q_SYNC: |
2138 | case Q_QUOTAON: | |
2139 | case Q_QUOTAOFF: | |
2140 | case Q_SETINFO: | |
2141 | case Q_SETQUOTA: | |
88e67f3b | 2142 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
2143 | break; |
2144 | case Q_GETFMT: | |
2145 | case Q_GETINFO: | |
2146 | case Q_GETQUOTA: | |
88e67f3b | 2147 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
2148 | break; |
2149 | default: | |
2150 | rc = 0; /* let the kernel handle invalid cmds */ | |
2151 | break; | |
1da177e4 LT |
2152 | } |
2153 | return rc; | |
2154 | } | |
2155 | ||
2156 | static int selinux_quota_on(struct dentry *dentry) | |
2157 | { | |
88e67f3b DH |
2158 | const struct cred *cred = current_cred(); |
2159 | ||
2875fa00 | 2160 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
2161 | } |
2162 | ||
12b3052c | 2163 | static int selinux_syslog(int type) |
1da177e4 | 2164 | { |
1da177e4 | 2165 | switch (type) { |
d78ca3cd KC |
2166 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2167 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
6b6bc620 SS |
2168 | return avc_has_perm(&selinux_state, |
2169 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2170 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); |
d78ca3cd KC |
2171 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2172 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2173 | /* Set level of messages printed to console */ | |
2174 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
6b6bc620 SS |
2175 | return avc_has_perm(&selinux_state, |
2176 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 SS |
2177 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, |
2178 | NULL); | |
1da177e4 | 2179 | } |
be0554c9 | 2180 | /* All other syslog types */ |
6b6bc620 SS |
2181 | return avc_has_perm(&selinux_state, |
2182 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2183 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); |
1da177e4 LT |
2184 | } |
2185 | ||
2186 | /* | |
2187 | * Check that a process has enough memory to allocate a new virtual | |
2188 | * mapping. 0 means there is enough memory for the allocation to | |
2189 | * succeed and -ENOMEM implies there is not. | |
2190 | * | |
1da177e4 LT |
2191 | * Do not audit the selinux permission check, as this is applied to all |
2192 | * processes that allocate mappings. | |
2193 | */ | |
34b4e4aa | 2194 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2195 | { |
2196 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2197 | |
b1d9e6b0 | 2198 | rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, |
c1a85a00 | 2199 | CAP_OPT_NOAUDIT, true); |
1da177e4 LT |
2200 | if (rc == 0) |
2201 | cap_sys_admin = 1; | |
2202 | ||
b1d9e6b0 | 2203 | return cap_sys_admin; |
1da177e4 LT |
2204 | } |
2205 | ||
2206 | /* binprm security operations */ | |
2207 | ||
be0554c9 | 2208 | static u32 ptrace_parent_sid(void) |
0c6181cb PM |
2209 | { |
2210 | u32 sid = 0; | |
2211 | struct task_struct *tracer; | |
2212 | ||
2213 | rcu_read_lock(); | |
be0554c9 | 2214 | tracer = ptrace_parent(current); |
0c6181cb PM |
2215 | if (tracer) |
2216 | sid = task_sid(tracer); | |
2217 | rcu_read_unlock(); | |
2218 | ||
2219 | return sid; | |
2220 | } | |
2221 | ||
7b0d0b40 SS |
2222 | static int check_nnp_nosuid(const struct linux_binprm *bprm, |
2223 | const struct task_security_struct *old_tsec, | |
2224 | const struct task_security_struct *new_tsec) | |
2225 | { | |
2226 | int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); | |
380cf5ba | 2227 | int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); |
7b0d0b40 | 2228 | int rc; |
af63f419 | 2229 | u32 av; |
7b0d0b40 SS |
2230 | |
2231 | if (!nnp && !nosuid) | |
2232 | return 0; /* neither NNP nor nosuid */ | |
2233 | ||
2234 | if (new_tsec->sid == old_tsec->sid) | |
2235 | return 0; /* No change in credentials */ | |
2236 | ||
2237 | /* | |
af63f419 SS |
2238 | * If the policy enables the nnp_nosuid_transition policy capability, |
2239 | * then we permit transitions under NNP or nosuid if the | |
2240 | * policy allows the corresponding permission between | |
2241 | * the old and new contexts. | |
7b0d0b40 | 2242 | */ |
aa8e712c | 2243 | if (selinux_policycap_nnp_nosuid_transition()) { |
af63f419 | 2244 | av = 0; |
7b0d0b40 | 2245 | if (nnp) |
af63f419 SS |
2246 | av |= PROCESS2__NNP_TRANSITION; |
2247 | if (nosuid) | |
2248 | av |= PROCESS2__NOSUID_TRANSITION; | |
6b6bc620 SS |
2249 | rc = avc_has_perm(&selinux_state, |
2250 | old_tsec->sid, new_tsec->sid, | |
af63f419 SS |
2251 | SECCLASS_PROCESS2, av, NULL); |
2252 | if (!rc) | |
2253 | return 0; | |
7b0d0b40 | 2254 | } |
af63f419 SS |
2255 | |
2256 | /* | |
2257 | * We also permit NNP or nosuid transitions to bounded SIDs, | |
2258 | * i.e. SIDs that are guaranteed to only be allowed a subset | |
2259 | * of the permissions of the current SID. | |
2260 | */ | |
aa8e712c SS |
2261 | rc = security_bounded_transition(&selinux_state, old_tsec->sid, |
2262 | new_tsec->sid); | |
af63f419 SS |
2263 | if (!rc) |
2264 | return 0; | |
2265 | ||
2266 | /* | |
2267 | * On failure, preserve the errno values for NNP vs nosuid. | |
2268 | * NNP: Operation not permitted for caller. | |
2269 | * nosuid: Permission denied to file. | |
2270 | */ | |
2271 | if (nnp) | |
2272 | return -EPERM; | |
2273 | return -EACCES; | |
7b0d0b40 SS |
2274 | } |
2275 | ||
a6f76f23 | 2276 | static int selinux_bprm_set_creds(struct linux_binprm *bprm) |
1da177e4 | 2277 | { |
a6f76f23 DH |
2278 | const struct task_security_struct *old_tsec; |
2279 | struct task_security_struct *new_tsec; | |
1da177e4 | 2280 | struct inode_security_struct *isec; |
2bf49690 | 2281 | struct common_audit_data ad; |
496ad9aa | 2282 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2283 | int rc; |
2284 | ||
a6f76f23 DH |
2285 | /* SELinux context only depends on initial program or script and not |
2286 | * the script interpreter */ | |
ddb4a144 | 2287 | if (bprm->called_set_creds) |
1da177e4 LT |
2288 | return 0; |
2289 | ||
0c6cfa62 CS |
2290 | old_tsec = selinux_cred(current_cred()); |
2291 | new_tsec = selinux_cred(bprm->cred); | |
83da53c5 | 2292 | isec = inode_security(inode); |
1da177e4 LT |
2293 | |
2294 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2295 | new_tsec->sid = old_tsec->sid; |
2296 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2297 | |
28eba5bf | 2298 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2299 | new_tsec->create_sid = 0; |
2300 | new_tsec->keycreate_sid = 0; | |
2301 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2302 | |
a6f76f23 DH |
2303 | if (old_tsec->exec_sid) { |
2304 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2305 | /* Reset exec SID on execve. */ |
a6f76f23 | 2306 | new_tsec->exec_sid = 0; |
259e5e6c | 2307 | |
7b0d0b40 SS |
2308 | /* Fail on NNP or nosuid if not an allowed transition. */ |
2309 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2310 | if (rc) | |
2311 | return rc; | |
1da177e4 LT |
2312 | } else { |
2313 | /* Check for a default transition on this program. */ | |
aa8e712c SS |
2314 | rc = security_transition_sid(&selinux_state, old_tsec->sid, |
2315 | isec->sid, SECCLASS_PROCESS, NULL, | |
652bb9b0 | 2316 | &new_tsec->sid); |
1da177e4 LT |
2317 | if (rc) |
2318 | return rc; | |
7b0d0b40 SS |
2319 | |
2320 | /* | |
2321 | * Fallback to old SID on NNP or nosuid if not an allowed | |
2322 | * transition. | |
2323 | */ | |
2324 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2325 | if (rc) | |
2326 | new_tsec->sid = old_tsec->sid; | |
1da177e4 LT |
2327 | } |
2328 | ||
43af5de7 VG |
2329 | ad.type = LSM_AUDIT_DATA_FILE; |
2330 | ad.u.file = bprm->file; | |
1da177e4 | 2331 | |
a6f76f23 | 2332 | if (new_tsec->sid == old_tsec->sid) { |
6b6bc620 SS |
2333 | rc = avc_has_perm(&selinux_state, |
2334 | old_tsec->sid, isec->sid, | |
1da177e4 LT |
2335 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2336 | if (rc) | |
2337 | return rc; | |
2338 | } else { | |
2339 | /* Check permissions for the transition. */ | |
6b6bc620 SS |
2340 | rc = avc_has_perm(&selinux_state, |
2341 | old_tsec->sid, new_tsec->sid, | |
1da177e4 LT |
2342 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2343 | if (rc) | |
2344 | return rc; | |
2345 | ||
6b6bc620 SS |
2346 | rc = avc_has_perm(&selinux_state, |
2347 | new_tsec->sid, isec->sid, | |
1da177e4 LT |
2348 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2349 | if (rc) | |
2350 | return rc; | |
2351 | ||
a6f76f23 DH |
2352 | /* Check for shared state */ |
2353 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
6b6bc620 SS |
2354 | rc = avc_has_perm(&selinux_state, |
2355 | old_tsec->sid, new_tsec->sid, | |
a6f76f23 DH |
2356 | SECCLASS_PROCESS, PROCESS__SHARE, |
2357 | NULL); | |
2358 | if (rc) | |
2359 | return -EPERM; | |
2360 | } | |
2361 | ||
2362 | /* Make sure that anyone attempting to ptrace over a task that | |
2363 | * changes its SID has the appropriate permit */ | |
9227dd2a | 2364 | if (bprm->unsafe & LSM_UNSAFE_PTRACE) { |
be0554c9 | 2365 | u32 ptsid = ptrace_parent_sid(); |
a6f76f23 | 2366 | if (ptsid != 0) { |
6b6bc620 SS |
2367 | rc = avc_has_perm(&selinux_state, |
2368 | ptsid, new_tsec->sid, | |
a6f76f23 DH |
2369 | SECCLASS_PROCESS, |
2370 | PROCESS__PTRACE, NULL); | |
2371 | if (rc) | |
2372 | return -EPERM; | |
2373 | } | |
2374 | } | |
1da177e4 | 2375 | |
a6f76f23 DH |
2376 | /* Clear any possibly unsafe personality bits on exec: */ |
2377 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
275bb41e | 2378 | |
1da177e4 LT |
2379 | /* Enable secure mode for SIDs transitions unless |
2380 | the noatsecure permission is granted between | |
2381 | the two SIDs, i.e. ahp returns 0. */ | |
6b6bc620 SS |
2382 | rc = avc_has_perm(&selinux_state, |
2383 | old_tsec->sid, new_tsec->sid, | |
62874c3a KC |
2384 | SECCLASS_PROCESS, PROCESS__NOATSECURE, |
2385 | NULL); | |
2386 | bprm->secureexec |= !!rc; | |
1da177e4 LT |
2387 | } |
2388 | ||
62874c3a | 2389 | return 0; |
1da177e4 LT |
2390 | } |
2391 | ||
c3c073f8 AV |
2392 | static int match_file(const void *p, struct file *file, unsigned fd) |
2393 | { | |
2394 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2395 | } | |
2396 | ||
1da177e4 | 2397 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2398 | static inline void flush_unauthorized_files(const struct cred *cred, |
2399 | struct files_struct *files) | |
1da177e4 | 2400 | { |
1da177e4 | 2401 | struct file *file, *devnull = NULL; |
b20c8122 | 2402 | struct tty_struct *tty; |
24ec839c | 2403 | int drop_tty = 0; |
c3c073f8 | 2404 | unsigned n; |
1da177e4 | 2405 | |
24ec839c | 2406 | tty = get_current_tty(); |
1da177e4 | 2407 | if (tty) { |
4a510969 | 2408 | spin_lock(&tty->files_lock); |
37dd0bd0 | 2409 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2410 | struct tty_file_private *file_priv; |
37dd0bd0 | 2411 | |
1da177e4 | 2412 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2413 | Use file_path_has_perm on the tty path directly |
2414 | rather than using file_has_perm, as this particular | |
2415 | open file may belong to another process and we are | |
2416 | only interested in the inode-based check here. */ | |
d996b62a NP |
2417 | file_priv = list_first_entry(&tty->tty_files, |
2418 | struct tty_file_private, list); | |
2419 | file = file_priv->file; | |
13f8e981 | 2420 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2421 | drop_tty = 1; |
1da177e4 | 2422 | } |
4a510969 | 2423 | spin_unlock(&tty->files_lock); |
452a00d2 | 2424 | tty_kref_put(tty); |
1da177e4 | 2425 | } |
98a27ba4 EB |
2426 | /* Reset controlling tty. */ |
2427 | if (drop_tty) | |
2428 | no_tty(); | |
1da177e4 LT |
2429 | |
2430 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2431 | n = iterate_fd(files, 0, match_file, cred); |
2432 | if (!n) /* none found? */ | |
2433 | return; | |
1da177e4 | 2434 | |
c3c073f8 | 2435 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2436 | if (IS_ERR(devnull)) |
2437 | devnull = NULL; | |
2438 | /* replace all the matching ones with this */ | |
2439 | do { | |
2440 | replace_fd(n - 1, devnull, 0); | |
2441 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2442 | if (devnull) | |
c3c073f8 | 2443 | fput(devnull); |
1da177e4 LT |
2444 | } |
2445 | ||
a6f76f23 DH |
2446 | /* |
2447 | * Prepare a process for imminent new credential changes due to exec | |
2448 | */ | |
2449 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2450 | { |
a6f76f23 DH |
2451 | struct task_security_struct *new_tsec; |
2452 | struct rlimit *rlim, *initrlim; | |
2453 | int rc, i; | |
d84f4f99 | 2454 | |
0c6cfa62 | 2455 | new_tsec = selinux_cred(bprm->cred); |
a6f76f23 DH |
2456 | if (new_tsec->sid == new_tsec->osid) |
2457 | return; | |
1da177e4 | 2458 | |
a6f76f23 DH |
2459 | /* Close files for which the new task SID is not authorized. */ |
2460 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2461 | |
a6f76f23 DH |
2462 | /* Always clear parent death signal on SID transitions. */ |
2463 | current->pdeath_signal = 0; | |
0356357c | 2464 | |
a6f76f23 DH |
2465 | /* Check whether the new SID can inherit resource limits from the old |
2466 | * SID. If not, reset all soft limits to the lower of the current | |
2467 | * task's hard limit and the init task's soft limit. | |
2468 | * | |
2469 | * Note that the setting of hard limits (even to lower them) can be | |
2470 | * controlled by the setrlimit check. The inclusion of the init task's | |
2471 | * soft limit into the computation is to avoid resetting soft limits | |
2472 | * higher than the default soft limit for cases where the default is | |
2473 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2474 | */ | |
6b6bc620 SS |
2475 | rc = avc_has_perm(&selinux_state, |
2476 | new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
a6f76f23 DH |
2477 | PROCESS__RLIMITINH, NULL); |
2478 | if (rc) { | |
eb2d55a3 ON |
2479 | /* protect against do_prlimit() */ |
2480 | task_lock(current); | |
a6f76f23 DH |
2481 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2482 | rlim = current->signal->rlim + i; | |
2483 | initrlim = init_task.signal->rlim + i; | |
2484 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2485 | } |
eb2d55a3 | 2486 | task_unlock(current); |
baa73d9e NP |
2487 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) |
2488 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2489 | } |
2490 | } | |
2491 | ||
2492 | /* | |
a6f76f23 DH |
2493 | * Clean up the process immediately after the installation of new credentials |
2494 | * due to exec | |
1da177e4 | 2495 | */ |
a6f76f23 | 2496 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2497 | { |
0c6cfa62 | 2498 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
a6f76f23 | 2499 | u32 osid, sid; |
ddbc7d06 | 2500 | int rc; |
1da177e4 | 2501 | |
a6f76f23 DH |
2502 | osid = tsec->osid; |
2503 | sid = tsec->sid; | |
2504 | ||
2505 | if (sid == osid) | |
1da177e4 LT |
2506 | return; |
2507 | ||
a6f76f23 DH |
2508 | /* Check whether the new SID can inherit signal state from the old SID. |
2509 | * If not, clear itimers to avoid subsequent signal generation and | |
2510 | * flush and unblock signals. | |
2511 | * | |
2512 | * This must occur _after_ the task SID has been updated so that any | |
2513 | * kill done after the flush will be checked against the new SID. | |
2514 | */ | |
6b6bc620 SS |
2515 | rc = avc_has_perm(&selinux_state, |
2516 | osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 | 2517 | if (rc) { |
ddbc7d06 AB |
2518 | clear_itimer(); |
2519 | ||
1da177e4 | 2520 | spin_lock_irq(¤t->sighand->siglock); |
9e7c8f8c ON |
2521 | if (!fatal_signal_pending(current)) { |
2522 | flush_sigqueue(¤t->pending); | |
2523 | flush_sigqueue(¤t->signal->shared_pending); | |
3bcac026 DH |
2524 | flush_signal_handlers(current, 1); |
2525 | sigemptyset(¤t->blocked); | |
9e7c8f8c | 2526 | recalc_sigpending(); |
3bcac026 | 2527 | } |
1da177e4 LT |
2528 | spin_unlock_irq(¤t->sighand->siglock); |
2529 | } | |
2530 | ||
a6f76f23 DH |
2531 | /* Wake up the parent if it is waiting so that it can recheck |
2532 | * wait permission to the new task SID. */ | |
ecd6de3c | 2533 | read_lock(&tasklist_lock); |
0b7570e7 | 2534 | __wake_up_parent(current, current->real_parent); |
ecd6de3c | 2535 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2536 | } |
2537 | ||
2538 | /* superblock security operations */ | |
2539 | ||
2540 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2541 | { | |
cb89e246 PM |
2542 | struct superblock_security_struct *sbsec; |
2543 | ||
2544 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); | |
2545 | if (!sbsec) | |
2546 | return -ENOMEM; | |
2547 | ||
2548 | mutex_init(&sbsec->lock); | |
2549 | INIT_LIST_HEAD(&sbsec->isec_head); | |
2550 | spin_lock_init(&sbsec->isec_lock); | |
2551 | sbsec->sb = sb; | |
2552 | sbsec->sid = SECINITSID_UNLABELED; | |
2553 | sbsec->def_sid = SECINITSID_FILE; | |
2554 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; | |
2555 | sb->s_security = sbsec; | |
2556 | ||
2557 | return 0; | |
1da177e4 LT |
2558 | } |
2559 | ||
2560 | static void selinux_sb_free_security(struct super_block *sb) | |
2561 | { | |
2562 | superblock_free_security(sb); | |
2563 | } | |
2564 | ||
99dbbb59 | 2565 | static inline int opt_len(const char *s) |
1da177e4 | 2566 | { |
99dbbb59 AV |
2567 | bool open_quote = false; |
2568 | int len; | |
2569 | char c; | |
1da177e4 | 2570 | |
99dbbb59 AV |
2571 | for (len = 0; (c = s[len]) != '\0'; len++) { |
2572 | if (c == '"') | |
2573 | open_quote = !open_quote; | |
2574 | if (c == ',' && !open_quote) | |
2575 | break; | |
3528a953 | 2576 | } |
99dbbb59 | 2577 | return len; |
3528a953 CO |
2578 | } |
2579 | ||
99dbbb59 | 2580 | static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) |
1da177e4 | 2581 | { |
99dbbb59 AV |
2582 | char *from = options; |
2583 | char *to = options; | |
2584 | bool first = true; | |
fec63753 | 2585 | int rc; |
1da177e4 | 2586 | |
99dbbb59 AV |
2587 | while (1) { |
2588 | int len = opt_len(from); | |
fec63753 | 2589 | int token; |
99dbbb59 | 2590 | char *arg = NULL; |
1da177e4 | 2591 | |
99dbbb59 | 2592 | token = match_opt_prefix(from, len, &arg); |
1da177e4 | 2593 | |
99dbbb59 AV |
2594 | if (token != Opt_error) { |
2595 | char *p, *q; | |
1da177e4 | 2596 | |
99dbbb59 AV |
2597 | /* strip quotes */ |
2598 | if (arg) { | |
2599 | for (p = q = arg; p < from + len; p++) { | |
2600 | char c = *p; | |
2601 | if (c != '"') | |
2602 | *q++ = c; | |
2603 | } | |
2604 | arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); | |
fec63753 GZ |
2605 | if (!arg) { |
2606 | rc = -ENOMEM; | |
2607 | goto free_opt; | |
2608 | } | |
99dbbb59 AV |
2609 | } |
2610 | rc = selinux_add_opt(token, arg, mnt_opts); | |
2611 | if (unlikely(rc)) { | |
2612 | kfree(arg); | |
fec63753 | 2613 | goto free_opt; |
99dbbb59 AV |
2614 | } |
2615 | } else { | |
2616 | if (!first) { // copy with preceding comma | |
2617 | from--; | |
2618 | len++; | |
2619 | } | |
2620 | if (to != from) | |
2621 | memmove(to, from, len); | |
2622 | to += len; | |
2623 | first = false; | |
1da177e4 | 2624 | } |
99dbbb59 AV |
2625 | if (!from[len]) |
2626 | break; | |
2627 | from += len + 1; | |
2628 | } | |
2629 | *to = '\0'; | |
2630 | return 0; | |
fec63753 GZ |
2631 | |
2632 | free_opt: | |
2633 | if (*mnt_opts) { | |
2634 | selinux_free_mnt_opts(*mnt_opts); | |
2635 | *mnt_opts = NULL; | |
2636 | } | |
2637 | return rc; | |
1da177e4 LT |
2638 | } |
2639 | ||
204cc0cc | 2640 | static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) |
026eb167 | 2641 | { |
bd323655 | 2642 | struct selinux_mnt_opts *opts = mnt_opts; |
026eb167 | 2643 | struct superblock_security_struct *sbsec = sb->s_security; |
bd323655 AV |
2644 | u32 sid; |
2645 | int rc; | |
026eb167 EP |
2646 | |
2647 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2648 | return 0; | |
2649 | ||
204cc0cc | 2650 | if (!opts) |
026eb167 EP |
2651 | return 0; |
2652 | ||
bd323655 AV |
2653 | if (opts->fscontext) { |
2654 | rc = parse_sid(sb, opts->fscontext, &sid); | |
2655 | if (rc) | |
c039bc3c | 2656 | return rc; |
bd323655 AV |
2657 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) |
2658 | goto out_bad_option; | |
026eb167 | 2659 | } |
bd323655 AV |
2660 | if (opts->context) { |
2661 | rc = parse_sid(sb, opts->context, &sid); | |
2662 | if (rc) | |
2663 | return rc; | |
2664 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2665 | goto out_bad_option; | |
2666 | } | |
2667 | if (opts->rootcontext) { | |
2668 | struct inode_security_struct *root_isec; | |
2669 | root_isec = backing_inode_security(sb->s_root); | |
2670 | rc = parse_sid(sb, opts->rootcontext, &sid); | |
2671 | if (rc) | |
2672 | return rc; | |
2673 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2674 | goto out_bad_option; | |
2675 | } | |
2676 | if (opts->defcontext) { | |
2677 | rc = parse_sid(sb, opts->defcontext, &sid); | |
2678 | if (rc) | |
2679 | return rc; | |
2680 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2681 | goto out_bad_option; | |
026eb167 | 2682 | } |
c039bc3c | 2683 | return 0; |
026eb167 | 2684 | |
026eb167 | 2685 | out_bad_option: |
c103a91e | 2686 | pr_warn("SELinux: unable to change security options " |
29b1deb2 LT |
2687 | "during remount (dev %s, type=%s)\n", sb->s_id, |
2688 | sb->s_type->name); | |
c039bc3c | 2689 | return -EINVAL; |
026eb167 EP |
2690 | } |
2691 | ||
a10d7c22 | 2692 | static int selinux_sb_kern_mount(struct super_block *sb) |
1da177e4 | 2693 | { |
88e67f3b | 2694 | const struct cred *cred = current_cred(); |
2bf49690 | 2695 | struct common_audit_data ad; |
74192246 | 2696 | |
50c205f5 | 2697 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2698 | ad.u.dentry = sb->s_root; |
88e67f3b | 2699 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2700 | } |
2701 | ||
726c3342 | 2702 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2703 | { |
88e67f3b | 2704 | const struct cred *cred = current_cred(); |
2bf49690 | 2705 | struct common_audit_data ad; |
1da177e4 | 2706 | |
50c205f5 | 2707 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2708 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2709 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2710 | } |
2711 | ||
808d4e3c | 2712 | static int selinux_mount(const char *dev_name, |
8a04c43b | 2713 | const struct path *path, |
808d4e3c | 2714 | const char *type, |
828dfe1d EP |
2715 | unsigned long flags, |
2716 | void *data) | |
1da177e4 | 2717 | { |
88e67f3b | 2718 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2719 | |
2720 | if (flags & MS_REMOUNT) | |
d8c9584e | 2721 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2722 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2723 | else |
2875fa00 | 2724 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2725 | } |
2726 | ||
98aa0034 SS |
2727 | static int selinux_move_mount(const struct path *from_path, |
2728 | const struct path *to_path) | |
2729 | { | |
2730 | const struct cred *cred = current_cred(); | |
2731 | ||
2732 | return path_has_perm(cred, to_path, FILE__MOUNTON); | |
2733 | } | |
2734 | ||
1da177e4 LT |
2735 | static int selinux_umount(struct vfsmount *mnt, int flags) |
2736 | { | |
88e67f3b | 2737 | const struct cred *cred = current_cred(); |
1da177e4 | 2738 | |
88e67f3b | 2739 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2740 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2741 | } |
2742 | ||
0b52075e AV |
2743 | static int selinux_fs_context_dup(struct fs_context *fc, |
2744 | struct fs_context *src_fc) | |
2745 | { | |
2746 | const struct selinux_mnt_opts *src = src_fc->security; | |
2747 | struct selinux_mnt_opts *opts; | |
2748 | ||
2749 | if (!src) | |
2750 | return 0; | |
2751 | ||
2752 | fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); | |
2753 | if (!fc->security) | |
2754 | return -ENOMEM; | |
2755 | ||
2756 | opts = fc->security; | |
2757 | ||
2758 | if (src->fscontext) { | |
2759 | opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL); | |
2760 | if (!opts->fscontext) | |
2761 | return -ENOMEM; | |
2762 | } | |
2763 | if (src->context) { | |
2764 | opts->context = kstrdup(src->context, GFP_KERNEL); | |
2765 | if (!opts->context) | |
2766 | return -ENOMEM; | |
2767 | } | |
2768 | if (src->rootcontext) { | |
2769 | opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL); | |
2770 | if (!opts->rootcontext) | |
2771 | return -ENOMEM; | |
2772 | } | |
2773 | if (src->defcontext) { | |
2774 | opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL); | |
2775 | if (!opts->defcontext) | |
2776 | return -ENOMEM; | |
2777 | } | |
2778 | return 0; | |
2779 | } | |
2780 | ||
d7167b14 | 2781 | static const struct fs_parameter_spec selinux_fs_parameters[] = { |
442155c1 DH |
2782 | fsparam_string(CONTEXT_STR, Opt_context), |
2783 | fsparam_string(DEFCONTEXT_STR, Opt_defcontext), | |
2784 | fsparam_string(FSCONTEXT_STR, Opt_fscontext), | |
2785 | fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), | |
2786 | fsparam_flag (SECLABEL_STR, Opt_seclabel), | |
2787 | {} | |
2788 | }; | |
2789 | ||
442155c1 DH |
2790 | static int selinux_fs_context_parse_param(struct fs_context *fc, |
2791 | struct fs_parameter *param) | |
2792 | { | |
2793 | struct fs_parse_result result; | |
2794 | int opt, rc; | |
2795 | ||
d7167b14 | 2796 | opt = fs_parse(fc, selinux_fs_parameters, param, &result); |
442155c1 DH |
2797 | if (opt < 0) |
2798 | return opt; | |
2799 | ||
2800 | rc = selinux_add_opt(opt, param->string, &fc->security); | |
2801 | if (!rc) { | |
2802 | param->string = NULL; | |
2803 | rc = 1; | |
2804 | } | |
2805 | return rc; | |
2806 | } | |
2807 | ||
1da177e4 LT |
2808 | /* inode security operations */ |
2809 | ||
2810 | static int selinux_inode_alloc_security(struct inode *inode) | |
2811 | { | |
cb89e246 PM |
2812 | struct inode_security_struct *isec = selinux_inode(inode); |
2813 | u32 sid = current_sid(); | |
2814 | ||
2815 | spin_lock_init(&isec->lock); | |
2816 | INIT_LIST_HEAD(&isec->list); | |
2817 | isec->inode = inode; | |
2818 | isec->sid = SECINITSID_UNLABELED; | |
2819 | isec->sclass = SECCLASS_FILE; | |
2820 | isec->task_sid = sid; | |
2821 | isec->initialized = LABEL_INVALID; | |
2822 | ||
2823 | return 0; | |
1da177e4 LT |
2824 | } |
2825 | ||
2826 | static void selinux_inode_free_security(struct inode *inode) | |
2827 | { | |
2828 | inode_free_security(inode); | |
2829 | } | |
2830 | ||
d47be3df | 2831 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
4f3ccd76 | 2832 | const struct qstr *name, void **ctx, |
d47be3df DQ |
2833 | u32 *ctxlen) |
2834 | { | |
d47be3df DQ |
2835 | u32 newsid; |
2836 | int rc; | |
2837 | ||
0c6cfa62 | 2838 | rc = selinux_determine_inode_label(selinux_cred(current_cred()), |
c957f6df | 2839 | d_inode(dentry->d_parent), name, |
c3c188b2 DH |
2840 | inode_mode_to_security_class(mode), |
2841 | &newsid); | |
2842 | if (rc) | |
2843 | return rc; | |
d47be3df | 2844 | |
aa8e712c SS |
2845 | return security_sid_to_context(&selinux_state, newsid, (char **)ctx, |
2846 | ctxlen); | |
d47be3df DQ |
2847 | } |
2848 | ||
a518b0a5 VG |
2849 | static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, |
2850 | struct qstr *name, | |
2851 | const struct cred *old, | |
2852 | struct cred *new) | |
2853 | { | |
2854 | u32 newsid; | |
2855 | int rc; | |
2856 | struct task_security_struct *tsec; | |
2857 | ||
0c6cfa62 | 2858 | rc = selinux_determine_inode_label(selinux_cred(old), |
a518b0a5 VG |
2859 | d_inode(dentry->d_parent), name, |
2860 | inode_mode_to_security_class(mode), | |
2861 | &newsid); | |
2862 | if (rc) | |
2863 | return rc; | |
2864 | ||
0c6cfa62 | 2865 | tsec = selinux_cred(new); |
a518b0a5 VG |
2866 | tsec->create_sid = newsid; |
2867 | return 0; | |
2868 | } | |
2869 | ||
5e41ff9e | 2870 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
2871 | const struct qstr *qstr, |
2872 | const char **name, | |
2a7dba39 | 2873 | void **value, size_t *len) |
5e41ff9e | 2874 | { |
0c6cfa62 | 2875 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
5e41ff9e | 2876 | struct superblock_security_struct *sbsec; |
c0d4f464 | 2877 | u32 newsid, clen; |
5e41ff9e | 2878 | int rc; |
9548906b | 2879 | char *context; |
5e41ff9e | 2880 | |
5e41ff9e | 2881 | sbsec = dir->i_sb->s_security; |
5e41ff9e | 2882 | |
275bb41e DH |
2883 | newsid = tsec->create_sid; |
2884 | ||
210a2928 | 2885 | rc = selinux_determine_inode_label(tsec, dir, qstr, |
c3c188b2 DH |
2886 | inode_mode_to_security_class(inode->i_mode), |
2887 | &newsid); | |
2888 | if (rc) | |
2889 | return rc; | |
5e41ff9e | 2890 | |
296fddf7 | 2891 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 2892 | if (sbsec->flags & SE_SBINITIALIZED) { |
80788c22 | 2893 | struct inode_security_struct *isec = selinux_inode(inode); |
296fddf7 EP |
2894 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
2895 | isec->sid = newsid; | |
6f3be9f5 | 2896 | isec->initialized = LABEL_INITIALIZED; |
296fddf7 | 2897 | } |
5e41ff9e | 2898 | |
65cddd50 OM |
2899 | if (!selinux_initialized(&selinux_state) || |
2900 | !(sbsec->flags & SBLABEL_MNT)) | |
25a74f3b SS |
2901 | return -EOPNOTSUPP; |
2902 | ||
9548906b TH |
2903 | if (name) |
2904 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 2905 | |
570bc1c2 | 2906 | if (value && len) { |
aa8e712c SS |
2907 | rc = security_sid_to_context_force(&selinux_state, newsid, |
2908 | &context, &clen); | |
9548906b | 2909 | if (rc) |
570bc1c2 | 2910 | return rc; |
570bc1c2 SS |
2911 | *value = context; |
2912 | *len = clen; | |
5e41ff9e | 2913 | } |
5e41ff9e | 2914 | |
5e41ff9e SS |
2915 | return 0; |
2916 | } | |
2917 | ||
4acdaf27 | 2918 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
2919 | { |
2920 | return may_create(dir, dentry, SECCLASS_FILE); | |
2921 | } | |
2922 | ||
1da177e4 LT |
2923 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2924 | { | |
1da177e4 LT |
2925 | return may_link(dir, old_dentry, MAY_LINK); |
2926 | } | |
2927 | ||
1da177e4 LT |
2928 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2929 | { | |
1da177e4 LT |
2930 | return may_link(dir, dentry, MAY_UNLINK); |
2931 | } | |
2932 | ||
2933 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2934 | { | |
2935 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2936 | } | |
2937 | ||
18bb1db3 | 2938 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
2939 | { |
2940 | return may_create(dir, dentry, SECCLASS_DIR); | |
2941 | } | |
2942 | ||
1da177e4 LT |
2943 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2944 | { | |
2945 | return may_link(dir, dentry, MAY_RMDIR); | |
2946 | } | |
2947 | ||
1a67aafb | 2948 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 2949 | { |
1da177e4 LT |
2950 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
2951 | } | |
2952 | ||
1da177e4 | 2953 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 2954 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
2955 | { |
2956 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2957 | } | |
2958 | ||
1da177e4 LT |
2959 | static int selinux_inode_readlink(struct dentry *dentry) |
2960 | { | |
88e67f3b DH |
2961 | const struct cred *cred = current_cred(); |
2962 | ||
2875fa00 | 2963 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
2964 | } |
2965 | ||
bda0be7a N |
2966 | static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, |
2967 | bool rcu) | |
1da177e4 | 2968 | { |
88e67f3b | 2969 | const struct cred *cred = current_cred(); |
bda0be7a N |
2970 | struct common_audit_data ad; |
2971 | struct inode_security_struct *isec; | |
2972 | u32 sid; | |
1da177e4 | 2973 | |
bda0be7a N |
2974 | validate_creds(cred); |
2975 | ||
2976 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
2977 | ad.u.dentry = dentry; | |
2978 | sid = cred_sid(cred); | |
5d226df4 AG |
2979 | isec = inode_security_rcu(inode, rcu); |
2980 | if (IS_ERR(isec)) | |
2981 | return PTR_ERR(isec); | |
bda0be7a | 2982 | |
1a37079c SS |
2983 | return avc_has_perm_flags(&selinux_state, |
2984 | sid, isec->sid, isec->sclass, FILE__READ, &ad, | |
2985 | rcu ? MAY_NOT_BLOCK : 0); | |
1da177e4 LT |
2986 | } |
2987 | ||
d4cf970d EP |
2988 | static noinline int audit_inode_permission(struct inode *inode, |
2989 | u32 perms, u32 audited, u32 denied, | |
0188d5c0 | 2990 | int result) |
1da177e4 | 2991 | { |
b782e0a6 | 2992 | struct common_audit_data ad; |
80788c22 | 2993 | struct inode_security_struct *isec = selinux_inode(inode); |
d4cf970d EP |
2994 | int rc; |
2995 | ||
50c205f5 | 2996 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
2997 | ad.u.inode = inode; |
2998 | ||
6b6bc620 SS |
2999 | rc = slow_avc_audit(&selinux_state, |
3000 | current_sid(), isec->sid, isec->sclass, perms, | |
0188d5c0 | 3001 | audited, denied, result, &ad); |
d4cf970d EP |
3002 | if (rc) |
3003 | return rc; | |
3004 | return 0; | |
3005 | } | |
3006 | ||
e74f71eb | 3007 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 3008 | { |
88e67f3b | 3009 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
3010 | u32 perms; |
3011 | bool from_access; | |
5298d0b9 | 3012 | bool no_block = mask & MAY_NOT_BLOCK; |
2e334057 EP |
3013 | struct inode_security_struct *isec; |
3014 | u32 sid; | |
3015 | struct av_decision avd; | |
3016 | int rc, rc2; | |
3017 | u32 audited, denied; | |
1da177e4 | 3018 | |
b782e0a6 | 3019 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
3020 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
3021 | ||
b782e0a6 EP |
3022 | /* No permission to check. Existence test. */ |
3023 | if (!mask) | |
1da177e4 | 3024 | return 0; |
1da177e4 | 3025 | |
2e334057 | 3026 | validate_creds(cred); |
b782e0a6 | 3027 | |
2e334057 EP |
3028 | if (unlikely(IS_PRIVATE(inode))) |
3029 | return 0; | |
b782e0a6 EP |
3030 | |
3031 | perms = file_mask_to_av(inode->i_mode, mask); | |
3032 | ||
2e334057 | 3033 | sid = cred_sid(cred); |
5298d0b9 | 3034 | isec = inode_security_rcu(inode, no_block); |
5d226df4 AG |
3035 | if (IS_ERR(isec)) |
3036 | return PTR_ERR(isec); | |
2e334057 | 3037 | |
6b6bc620 | 3038 | rc = avc_has_perm_noaudit(&selinux_state, |
3a28cff3 | 3039 | sid, isec->sid, isec->sclass, perms, |
5298d0b9 | 3040 | no_block ? AVC_NONBLOCKING : 0, |
3a28cff3 | 3041 | &avd); |
2e334057 EP |
3042 | audited = avc_audit_required(perms, &avd, rc, |
3043 | from_access ? FILE__AUDIT_ACCESS : 0, | |
3044 | &denied); | |
3045 | if (likely(!audited)) | |
3046 | return rc; | |
3047 | ||
0188d5c0 | 3048 | /* fall back to ref-walk if we have to generate audit */ |
5298d0b9 | 3049 | if (no_block) |
0188d5c0 SS |
3050 | return -ECHILD; |
3051 | ||
3052 | rc2 = audit_inode_permission(inode, perms, audited, denied, rc); | |
2e334057 EP |
3053 | if (rc2) |
3054 | return rc2; | |
3055 | return rc; | |
1da177e4 LT |
3056 | } |
3057 | ||
3058 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
3059 | { | |
88e67f3b | 3060 | const struct cred *cred = current_cred(); |
ccb54478 | 3061 | struct inode *inode = d_backing_inode(dentry); |
bc6a6008 | 3062 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 3063 | __u32 av = FILE__WRITE; |
1da177e4 | 3064 | |
bc6a6008 AW |
3065 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
3066 | if (ia_valid & ATTR_FORCE) { | |
3067 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
3068 | ATTR_FORCE); | |
3069 | if (!ia_valid) | |
3070 | return 0; | |
3071 | } | |
1da177e4 | 3072 | |
bc6a6008 AW |
3073 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
3074 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 3075 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 3076 | |
aa8e712c | 3077 | if (selinux_policycap_openperm() && |
ccb54478 SS |
3078 | inode->i_sb->s_magic != SOCKFS_MAGIC && |
3079 | (ia_valid & ATTR_SIZE) && | |
3080 | !(ia_valid & ATTR_FILE)) | |
95dbf739 EP |
3081 | av |= FILE__OPEN; |
3082 | ||
3083 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
3084 | } |
3085 | ||
3f7036a0 | 3086 | static int selinux_inode_getattr(const struct path *path) |
1da177e4 | 3087 | { |
3f7036a0 | 3088 | return path_has_perm(current_cred(), path, FILE__GETATTR); |
1da177e4 LT |
3089 | } |
3090 | ||
db59000a SS |
3091 | static bool has_cap_mac_admin(bool audit) |
3092 | { | |
3093 | const struct cred *cred = current_cred(); | |
c1a85a00 | 3094 | unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; |
db59000a | 3095 | |
c1a85a00 | 3096 | if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) |
db59000a | 3097 | return false; |
c1a85a00 | 3098 | if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) |
db59000a SS |
3099 | return false; |
3100 | return true; | |
3101 | } | |
3102 | ||
8f0cfa52 DH |
3103 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
3104 | const void *value, size_t size, int flags) | |
1da177e4 | 3105 | { |
c6f493d6 | 3106 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3107 | struct inode_security_struct *isec; |
1da177e4 | 3108 | struct superblock_security_struct *sbsec; |
2bf49690 | 3109 | struct common_audit_data ad; |
275bb41e | 3110 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
3111 | int rc = 0; |
3112 | ||
6b240306 EB |
3113 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3114 | rc = cap_inode_setxattr(dentry, name, value, size, flags); | |
3115 | if (rc) | |
3116 | return rc; | |
3117 | ||
3118 | /* Not an attribute we recognize, so just check the | |
3119 | ordinary setattr permission. */ | |
3120 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3121 | } | |
1da177e4 | 3122 | |
65cddd50 | 3123 | if (!selinux_initialized(&selinux_state)) |
3e3e24b4 JL |
3124 | return (inode_owner_or_capable(inode) ? 0 : -EPERM); |
3125 | ||
1da177e4 | 3126 | sbsec = inode->i_sb->s_security; |
12f348b9 | 3127 | if (!(sbsec->flags & SBLABEL_MNT)) |
1da177e4 LT |
3128 | return -EOPNOTSUPP; |
3129 | ||
2e149670 | 3130 | if (!inode_owner_or_capable(inode)) |
1da177e4 LT |
3131 | return -EPERM; |
3132 | ||
50c205f5 | 3133 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 3134 | ad.u.dentry = dentry; |
1da177e4 | 3135 | |
20cdef8d | 3136 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
3137 | rc = avc_has_perm(&selinux_state, |
3138 | sid, isec->sid, isec->sclass, | |
1da177e4 LT |
3139 | FILE__RELABELFROM, &ad); |
3140 | if (rc) | |
3141 | return rc; | |
3142 | ||
aa8e712c SS |
3143 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3144 | GFP_KERNEL); | |
12b29f34 | 3145 | if (rc == -EINVAL) { |
db59000a | 3146 | if (!has_cap_mac_admin(true)) { |
d6ea83ec EP |
3147 | struct audit_buffer *ab; |
3148 | size_t audit_size; | |
d6ea83ec EP |
3149 | |
3150 | /* We strip a nul only if it is at the end, otherwise the | |
3151 | * context contains a nul and we should audit that */ | |
e3fea3f7 | 3152 | if (value) { |
add24372 CIK |
3153 | const char *str = value; |
3154 | ||
e3fea3f7 AV |
3155 | if (str[size - 1] == '\0') |
3156 | audit_size = size - 1; | |
3157 | else | |
3158 | audit_size = size; | |
3159 | } else { | |
e3fea3f7 AV |
3160 | audit_size = 0; |
3161 | } | |
cdfb6b34 RGB |
3162 | ab = audit_log_start(audit_context(), |
3163 | GFP_ATOMIC, AUDIT_SELINUX_ERR); | |
d6ea83ec EP |
3164 | audit_log_format(ab, "op=setxattr invalid_context="); |
3165 | audit_log_n_untrustedstring(ab, value, audit_size); | |
3166 | audit_log_end(ab); | |
3167 | ||
12b29f34 | 3168 | return rc; |
d6ea83ec | 3169 | } |
aa8e712c SS |
3170 | rc = security_context_to_sid_force(&selinux_state, value, |
3171 | size, &newsid); | |
12b29f34 | 3172 | } |
1da177e4 LT |
3173 | if (rc) |
3174 | return rc; | |
3175 | ||
6b6bc620 SS |
3176 | rc = avc_has_perm(&selinux_state, |
3177 | sid, newsid, isec->sclass, | |
1da177e4 LT |
3178 | FILE__RELABELTO, &ad); |
3179 | if (rc) | |
3180 | return rc; | |
3181 | ||
aa8e712c SS |
3182 | rc = security_validate_transition(&selinux_state, isec->sid, newsid, |
3183 | sid, isec->sclass); | |
1da177e4 LT |
3184 | if (rc) |
3185 | return rc; | |
3186 | ||
6b6bc620 SS |
3187 | return avc_has_perm(&selinux_state, |
3188 | newsid, | |
1da177e4 LT |
3189 | sbsec->sid, |
3190 | SECCLASS_FILESYSTEM, | |
3191 | FILESYSTEM__ASSOCIATE, | |
3192 | &ad); | |
3193 | } | |
3194 | ||
8f0cfa52 | 3195 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 3196 | const void *value, size_t size, |
8f0cfa52 | 3197 | int flags) |
1da177e4 | 3198 | { |
c6f493d6 | 3199 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3200 | struct inode_security_struct *isec; |
1da177e4 LT |
3201 | u32 newsid; |
3202 | int rc; | |
3203 | ||
3204 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
3205 | /* Not an attribute we recognize, so nothing to do. */ | |
3206 | return; | |
3207 | } | |
3208 | ||
65cddd50 | 3209 | if (!selinux_initialized(&selinux_state)) { |
3e3e24b4 JL |
3210 | /* If we haven't even been initialized, then we can't validate |
3211 | * against a policy, so leave the label as invalid. It may | |
3212 | * resolve to a valid label on the next revalidation try if | |
3213 | * we've since initialized. | |
3214 | */ | |
3215 | return; | |
3216 | } | |
3217 | ||
aa8e712c SS |
3218 | rc = security_context_to_sid_force(&selinux_state, value, size, |
3219 | &newsid); | |
1da177e4 | 3220 | if (rc) { |
c103a91e | 3221 | pr_err("SELinux: unable to map context to SID" |
12b29f34 SS |
3222 | "for (%s, %lu), rc=%d\n", |
3223 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
3224 | return; |
3225 | } | |
3226 | ||
20cdef8d | 3227 | isec = backing_inode_security(dentry); |
9287aed2 | 3228 | spin_lock(&isec->lock); |
aa9c2669 | 3229 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3230 | isec->sid = newsid; |
6f3be9f5 | 3231 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3232 | spin_unlock(&isec->lock); |
aa9c2669 | 3233 | |
1da177e4 LT |
3234 | return; |
3235 | } | |
3236 | ||
8f0cfa52 | 3237 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 3238 | { |
88e67f3b DH |
3239 | const struct cred *cred = current_cred(); |
3240 | ||
2875fa00 | 3241 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3242 | } |
3243 | ||
828dfe1d | 3244 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 3245 | { |
88e67f3b DH |
3246 | const struct cred *cred = current_cred(); |
3247 | ||
2875fa00 | 3248 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3249 | } |
3250 | ||
8f0cfa52 | 3251 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 3252 | { |
6b240306 EB |
3253 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3254 | int rc = cap_inode_removexattr(dentry, name); | |
3255 | if (rc) | |
3256 | return rc; | |
3257 | ||
3258 | /* Not an attribute we recognize, so just check the | |
3259 | ordinary setattr permission. */ | |
3260 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3261 | } | |
1da177e4 LT |
3262 | |
3263 | /* No one is allowed to remove a SELinux security label. | |
3264 | You can change the label, but all data must be labeled. */ | |
3265 | return -EACCES; | |
3266 | } | |
3267 | ||
ac5656d8 AG |
3268 | static int selinux_path_notify(const struct path *path, u64 mask, |
3269 | unsigned int obj_type) | |
3270 | { | |
3271 | int ret; | |
3272 | u32 perm; | |
3273 | ||
3274 | struct common_audit_data ad; | |
3275 | ||
3276 | ad.type = LSM_AUDIT_DATA_PATH; | |
3277 | ad.u.path = *path; | |
3278 | ||
3279 | /* | |
3280 | * Set permission needed based on the type of mark being set. | |
3281 | * Performs an additional check for sb watches. | |
3282 | */ | |
3283 | switch (obj_type) { | |
3284 | case FSNOTIFY_OBJ_TYPE_VFSMOUNT: | |
3285 | perm = FILE__WATCH_MOUNT; | |
3286 | break; | |
3287 | case FSNOTIFY_OBJ_TYPE_SB: | |
3288 | perm = FILE__WATCH_SB; | |
3289 | ret = superblock_has_perm(current_cred(), path->dentry->d_sb, | |
3290 | FILESYSTEM__WATCH, &ad); | |
3291 | if (ret) | |
3292 | return ret; | |
3293 | break; | |
3294 | case FSNOTIFY_OBJ_TYPE_INODE: | |
3295 | perm = FILE__WATCH; | |
3296 | break; | |
3297 | default: | |
3298 | return -EINVAL; | |
3299 | } | |
3300 | ||
3301 | /* blocking watches require the file:watch_with_perm permission */ | |
3302 | if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) | |
3303 | perm |= FILE__WATCH_WITH_PERM; | |
3304 | ||
3305 | /* watches on read-like events need the file:watch_reads permission */ | |
3306 | if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) | |
3307 | perm |= FILE__WATCH_READS; | |
3308 | ||
3309 | return path_has_perm(current_cred(), path, perm); | |
3310 | } | |
3311 | ||
d381d8a9 | 3312 | /* |
abc69bb6 | 3313 | * Copy the inode security context value to the user. |
d381d8a9 JM |
3314 | * |
3315 | * Permission check is handled by selinux_inode_getxattr hook. | |
3316 | */ | |
ea861dfd | 3317 | static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 3318 | { |
42492594 DQ |
3319 | u32 size; |
3320 | int error; | |
3321 | char *context = NULL; | |
20cdef8d | 3322 | struct inode_security_struct *isec; |
d381d8a9 | 3323 | |
8c8570fb DK |
3324 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
3325 | return -EOPNOTSUPP; | |
d381d8a9 | 3326 | |
abc69bb6 SS |
3327 | /* |
3328 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3329 | * value even if it is not defined by current policy; otherwise, | |
3330 | * use the in-core value under current policy. | |
3331 | * Use the non-auditing forms of the permission checks since | |
3332 | * getxattr may be called by unprivileged processes commonly | |
3333 | * and lack of permission just means that we fall back to the | |
3334 | * in-core context value, not a denial. | |
3335 | */ | |
20cdef8d | 3336 | isec = inode_security(inode); |
db59000a | 3337 | if (has_cap_mac_admin(false)) |
aa8e712c SS |
3338 | error = security_sid_to_context_force(&selinux_state, |
3339 | isec->sid, &context, | |
abc69bb6 SS |
3340 | &size); |
3341 | else | |
aa8e712c SS |
3342 | error = security_sid_to_context(&selinux_state, isec->sid, |
3343 | &context, &size); | |
42492594 DQ |
3344 | if (error) |
3345 | return error; | |
3346 | error = size; | |
3347 | if (alloc) { | |
3348 | *buffer = context; | |
3349 | goto out_nofree; | |
3350 | } | |
3351 | kfree(context); | |
3352 | out_nofree: | |
3353 | return error; | |
1da177e4 LT |
3354 | } |
3355 | ||
3356 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 3357 | const void *value, size_t size, int flags) |
1da177e4 | 3358 | { |
2c97165b | 3359 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
53e0c2aa | 3360 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; |
1da177e4 LT |
3361 | u32 newsid; |
3362 | int rc; | |
3363 | ||
3364 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3365 | return -EOPNOTSUPP; | |
3366 | ||
53e0c2aa OM |
3367 | if (!(sbsec->flags & SBLABEL_MNT)) |
3368 | return -EOPNOTSUPP; | |
3369 | ||
1da177e4 LT |
3370 | if (!value || !size) |
3371 | return -EACCES; | |
3372 | ||
aa8e712c SS |
3373 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3374 | GFP_KERNEL); | |
1da177e4 LT |
3375 | if (rc) |
3376 | return rc; | |
3377 | ||
9287aed2 | 3378 | spin_lock(&isec->lock); |
aa9c2669 | 3379 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3380 | isec->sid = newsid; |
6f3be9f5 | 3381 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3382 | spin_unlock(&isec->lock); |
1da177e4 LT |
3383 | return 0; |
3384 | } | |
3385 | ||
3386 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3387 | { | |
3388 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3389 | if (buffer && len <= buffer_size) | |
3390 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3391 | return len; | |
3392 | } | |
3393 | ||
d6335d77 | 3394 | static void selinux_inode_getsecid(struct inode *inode, u32 *secid) |
713a04ae | 3395 | { |
e817c2f3 | 3396 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
713a04ae AD |
3397 | *secid = isec->sid; |
3398 | } | |
3399 | ||
56909eb3 VG |
3400 | static int selinux_inode_copy_up(struct dentry *src, struct cred **new) |
3401 | { | |
3402 | u32 sid; | |
3403 | struct task_security_struct *tsec; | |
3404 | struct cred *new_creds = *new; | |
3405 | ||
3406 | if (new_creds == NULL) { | |
3407 | new_creds = prepare_creds(); | |
3408 | if (!new_creds) | |
3409 | return -ENOMEM; | |
3410 | } | |
3411 | ||
0c6cfa62 | 3412 | tsec = selinux_cred(new_creds); |
56909eb3 VG |
3413 | /* Get label from overlay inode and set it in create_sid */ |
3414 | selinux_inode_getsecid(d_inode(src), &sid); | |
3415 | tsec->create_sid = sid; | |
3416 | *new = new_creds; | |
3417 | return 0; | |
3418 | } | |
3419 | ||
19472b69 VG |
3420 | static int selinux_inode_copy_up_xattr(const char *name) |
3421 | { | |
3422 | /* The copy_up hook above sets the initial context on an inode, but we | |
3423 | * don't then want to overwrite it by blindly copying all the lower | |
3424 | * xattrs up. Instead, we have to filter out SELinux-related xattrs. | |
3425 | */ | |
3426 | if (strcmp(name, XATTR_NAME_SELINUX) == 0) | |
3427 | return 1; /* Discard */ | |
3428 | /* | |
3429 | * Any other attribute apart from SELINUX is not claimed, supported | |
3430 | * by selinux. | |
3431 | */ | |
3432 | return -EOPNOTSUPP; | |
3433 | } | |
3434 | ||
ec882da5 OM |
3435 | /* kernfs node operations */ |
3436 | ||
c72c4cde Y |
3437 | static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, |
3438 | struct kernfs_node *kn) | |
ec882da5 | 3439 | { |
169ce0c0 | 3440 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
ec882da5 OM |
3441 | u32 parent_sid, newsid, clen; |
3442 | int rc; | |
3443 | char *context; | |
3444 | ||
1537ad15 | 3445 | rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); |
ec882da5 OM |
3446 | if (rc == -ENODATA) |
3447 | return 0; | |
3448 | else if (rc < 0) | |
3449 | return rc; | |
3450 | ||
3451 | clen = (u32)rc; | |
3452 | context = kmalloc(clen, GFP_KERNEL); | |
3453 | if (!context) | |
3454 | return -ENOMEM; | |
3455 | ||
1537ad15 | 3456 | rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); |
ec882da5 OM |
3457 | if (rc < 0) { |
3458 | kfree(context); | |
3459 | return rc; | |
3460 | } | |
3461 | ||
3462 | rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid, | |
3463 | GFP_KERNEL); | |
3464 | kfree(context); | |
3465 | if (rc) | |
3466 | return rc; | |
3467 | ||
3468 | if (tsec->create_sid) { | |
3469 | newsid = tsec->create_sid; | |
3470 | } else { | |
3471 | u16 secclass = inode_mode_to_security_class(kn->mode); | |
3472 | struct qstr q; | |
3473 | ||
3474 | q.name = kn->name; | |
3475 | q.hash_len = hashlen_string(kn_dir, kn->name); | |
3476 | ||
3477 | rc = security_transition_sid(&selinux_state, tsec->sid, | |
3478 | parent_sid, secclass, &q, | |
3479 | &newsid); | |
3480 | if (rc) | |
3481 | return rc; | |
3482 | } | |
3483 | ||
3484 | rc = security_sid_to_context_force(&selinux_state, newsid, | |
3485 | &context, &clen); | |
3486 | if (rc) | |
3487 | return rc; | |
3488 | ||
1537ad15 OM |
3489 | rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, |
3490 | XATTR_CREATE); | |
ec882da5 OM |
3491 | kfree(context); |
3492 | return rc; | |
3493 | } | |
3494 | ||
3495 | ||
1da177e4 LT |
3496 | /* file security operations */ |
3497 | ||
788e7dd4 | 3498 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3499 | { |
88e67f3b | 3500 | const struct cred *cred = current_cred(); |
496ad9aa | 3501 | struct inode *inode = file_inode(file); |
1da177e4 | 3502 | |
1da177e4 LT |
3503 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3504 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3505 | mask |= MAY_APPEND; | |
3506 | ||
389fb800 PM |
3507 | return file_has_perm(cred, file, |
3508 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3509 | } |
3510 | ||
788e7dd4 YN |
3511 | static int selinux_file_permission(struct file *file, int mask) |
3512 | { | |
496ad9aa | 3513 | struct inode *inode = file_inode(file); |
bb6c6b02 | 3514 | struct file_security_struct *fsec = selinux_file(file); |
b197367e | 3515 | struct inode_security_struct *isec; |
20dda18b SS |
3516 | u32 sid = current_sid(); |
3517 | ||
389fb800 | 3518 | if (!mask) |
788e7dd4 YN |
3519 | /* No permission to check. Existence test. */ |
3520 | return 0; | |
788e7dd4 | 3521 | |
b197367e | 3522 | isec = inode_security(inode); |
20dda18b | 3523 | if (sid == fsec->sid && fsec->isid == isec->sid && |
6b6bc620 | 3524 | fsec->pseqno == avc_policy_seqno(&selinux_state)) |
83d49856 | 3525 | /* No change since file_open check. */ |
20dda18b SS |
3526 | return 0; |
3527 | ||
788e7dd4 YN |
3528 | return selinux_revalidate_file_permission(file, mask); |
3529 | } | |
3530 | ||
1da177e4 LT |
3531 | static int selinux_file_alloc_security(struct file *file) |
3532 | { | |
cb89e246 PM |
3533 | struct file_security_struct *fsec = selinux_file(file); |
3534 | u32 sid = current_sid(); | |
3535 | ||
3536 | fsec->sid = sid; | |
3537 | fsec->fown_sid = sid; | |
3538 | ||
3539 | return 0; | |
1da177e4 LT |
3540 | } |
3541 | ||
fa1aa143 JVS |
3542 | /* |
3543 | * Check whether a task has the ioctl permission and cmd | |
3544 | * operation to an inode. | |
3545 | */ | |
1d2a168a | 3546 | static int ioctl_has_perm(const struct cred *cred, struct file *file, |
fa1aa143 JVS |
3547 | u32 requested, u16 cmd) |
3548 | { | |
3549 | struct common_audit_data ad; | |
bb6c6b02 | 3550 | struct file_security_struct *fsec = selinux_file(file); |
fa1aa143 | 3551 | struct inode *inode = file_inode(file); |
20cdef8d | 3552 | struct inode_security_struct *isec; |
fa1aa143 JVS |
3553 | struct lsm_ioctlop_audit ioctl; |
3554 | u32 ssid = cred_sid(cred); | |
3555 | int rc; | |
3556 | u8 driver = cmd >> 8; | |
3557 | u8 xperm = cmd & 0xff; | |
3558 | ||
3559 | ad.type = LSM_AUDIT_DATA_IOCTL_OP; | |
3560 | ad.u.op = &ioctl; | |
3561 | ad.u.op->cmd = cmd; | |
3562 | ad.u.op->path = file->f_path; | |
3563 | ||
3564 | if (ssid != fsec->sid) { | |
6b6bc620 SS |
3565 | rc = avc_has_perm(&selinux_state, |
3566 | ssid, fsec->sid, | |
fa1aa143 JVS |
3567 | SECCLASS_FD, |
3568 | FD__USE, | |
3569 | &ad); | |
3570 | if (rc) | |
3571 | goto out; | |
3572 | } | |
3573 | ||
3574 | if (unlikely(IS_PRIVATE(inode))) | |
3575 | return 0; | |
3576 | ||
20cdef8d | 3577 | isec = inode_security(inode); |
6b6bc620 SS |
3578 | rc = avc_has_extended_perms(&selinux_state, |
3579 | ssid, isec->sid, isec->sclass, | |
3580 | requested, driver, xperm, &ad); | |
fa1aa143 JVS |
3581 | out: |
3582 | return rc; | |
3583 | } | |
3584 | ||
1da177e4 LT |
3585 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
3586 | unsigned long arg) | |
3587 | { | |
88e67f3b | 3588 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3589 | int error = 0; |
1da177e4 | 3590 | |
0b24dcb7 EP |
3591 | switch (cmd) { |
3592 | case FIONREAD: | |
3593 | /* fall through */ | |
3594 | case FIBMAP: | |
3595 | /* fall through */ | |
3596 | case FIGETBSZ: | |
3597 | /* fall through */ | |
2f99c369 | 3598 | case FS_IOC_GETFLAGS: |
0b24dcb7 | 3599 | /* fall through */ |
2f99c369 | 3600 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3601 | error = file_has_perm(cred, file, FILE__GETATTR); |
3602 | break; | |
1da177e4 | 3603 | |
2f99c369 | 3604 | case FS_IOC_SETFLAGS: |
0b24dcb7 | 3605 | /* fall through */ |
2f99c369 | 3606 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3607 | error = file_has_perm(cred, file, FILE__SETATTR); |
3608 | break; | |
3609 | ||
3610 | /* sys_ioctl() checks */ | |
3611 | case FIONBIO: | |
3612 | /* fall through */ | |
3613 | case FIOASYNC: | |
3614 | error = file_has_perm(cred, file, 0); | |
3615 | break; | |
1da177e4 | 3616 | |
0b24dcb7 EP |
3617 | case KDSKBENT: |
3618 | case KDSKBSENT: | |
6a9de491 | 3619 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
c1a85a00 | 3620 | CAP_OPT_NONE, true); |
0b24dcb7 EP |
3621 | break; |
3622 | ||
3623 | /* default case assumes that the command will go | |
3624 | * to the file's ioctl() function. | |
3625 | */ | |
3626 | default: | |
fa1aa143 | 3627 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
0b24dcb7 EP |
3628 | } |
3629 | return error; | |
1da177e4 LT |
3630 | } |
3631 | ||
b78b7d59 | 3632 | static int default_noexec __ro_after_init; |
fcaaade1 | 3633 | |
1da177e4 LT |
3634 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3635 | { | |
88e67f3b | 3636 | const struct cred *cred = current_cred(); |
be0554c9 | 3637 | u32 sid = cred_sid(cred); |
d84f4f99 | 3638 | int rc = 0; |
88e67f3b | 3639 | |
fcaaade1 | 3640 | if (default_noexec && |
892e8cac SS |
3641 | (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || |
3642 | (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3643 | /* |
3644 | * We are making executable an anonymous mapping or a | |
3645 | * private file mapping that will also be writable. | |
3646 | * This has an additional check. | |
3647 | */ | |
6b6bc620 SS |
3648 | rc = avc_has_perm(&selinux_state, |
3649 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3650 | PROCESS__EXECMEM, NULL); |
1da177e4 | 3651 | if (rc) |
d84f4f99 | 3652 | goto error; |
1da177e4 | 3653 | } |
1da177e4 LT |
3654 | |
3655 | if (file) { | |
3656 | /* read access is always possible with a mapping */ | |
3657 | u32 av = FILE__READ; | |
3658 | ||
3659 | /* write access only matters if the mapping is shared */ | |
3660 | if (shared && (prot & PROT_WRITE)) | |
3661 | av |= FILE__WRITE; | |
3662 | ||
3663 | if (prot & PROT_EXEC) | |
3664 | av |= FILE__EXECUTE; | |
3665 | ||
88e67f3b | 3666 | return file_has_perm(cred, file, av); |
1da177e4 | 3667 | } |
d84f4f99 DH |
3668 | |
3669 | error: | |
3670 | return rc; | |
1da177e4 LT |
3671 | } |
3672 | ||
e5467859 | 3673 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3674 | { |
b1d9e6b0 | 3675 | int rc = 0; |
1da177e4 | 3676 | |
a2551df7 | 3677 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
98883bfd | 3678 | u32 sid = current_sid(); |
6b6bc620 SS |
3679 | rc = avc_has_perm(&selinux_state, |
3680 | sid, sid, SECCLASS_MEMPROTECT, | |
ed032189 | 3681 | MEMPROTECT__MMAP_ZERO, NULL); |
84336d1a EP |
3682 | } |
3683 | ||
98883bfd | 3684 | return rc; |
e5467859 | 3685 | } |
1da177e4 | 3686 | |
e5467859 AV |
3687 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3688 | unsigned long prot, unsigned long flags) | |
3689 | { | |
3ba4bf5f SS |
3690 | struct common_audit_data ad; |
3691 | int rc; | |
3692 | ||
3693 | if (file) { | |
3694 | ad.type = LSM_AUDIT_DATA_FILE; | |
3695 | ad.u.file = file; | |
3696 | rc = inode_has_perm(current_cred(), file_inode(file), | |
3697 | FILE__MAP, &ad); | |
3698 | if (rc) | |
3699 | return rc; | |
3700 | } | |
3701 | ||
aa8e712c | 3702 | if (selinux_state.checkreqprot) |
1da177e4 LT |
3703 | prot = reqprot; |
3704 | ||
3705 | return file_map_prot_check(file, prot, | |
3706 | (flags & MAP_TYPE) == MAP_SHARED); | |
3707 | } | |
3708 | ||
3709 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3710 | unsigned long reqprot, | |
3711 | unsigned long prot) | |
3712 | { | |
88e67f3b | 3713 | const struct cred *cred = current_cred(); |
be0554c9 | 3714 | u32 sid = cred_sid(cred); |
1da177e4 | 3715 | |
aa8e712c | 3716 | if (selinux_state.checkreqprot) |
1da177e4 LT |
3717 | prot = reqprot; |
3718 | ||
fcaaade1 SS |
3719 | if (default_noexec && |
3720 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3721 | int rc = 0; |
db4c9641 SS |
3722 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3723 | vma->vm_end <= vma->vm_mm->brk) { | |
6b6bc620 SS |
3724 | rc = avc_has_perm(&selinux_state, |
3725 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3726 | PROCESS__EXECHEAP, NULL); |
db4c9641 | 3727 | } else if (!vma->vm_file && |
c2316dbf SS |
3728 | ((vma->vm_start <= vma->vm_mm->start_stack && |
3729 | vma->vm_end >= vma->vm_mm->start_stack) || | |
d17af505 | 3730 | vma_is_stack_for_current(vma))) { |
6b6bc620 SS |
3731 | rc = avc_has_perm(&selinux_state, |
3732 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3733 | PROCESS__EXECSTACK, NULL); |
db4c9641 SS |
3734 | } else if (vma->vm_file && vma->anon_vma) { |
3735 | /* | |
3736 | * We are making executable a file mapping that has | |
3737 | * had some COW done. Since pages might have been | |
3738 | * written, check ability to execute the possibly | |
3739 | * modified content. This typically should only | |
3740 | * occur for text relocations. | |
3741 | */ | |
d84f4f99 | 3742 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3743 | } |