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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> |
b89999d0 | 27 | #include <linux/kernel_read_file.h> |
0d094efe | 28 | #include <linux/tracehook.h> |
1da177e4 | 29 | #include <linux/errno.h> |
3f07c014 | 30 | #include <linux/sched/signal.h> |
29930025 | 31 | #include <linux/sched/task.h> |
3c4ed7bd | 32 | #include <linux/lsm_hooks.h> |
1da177e4 LT |
33 | #include <linux/xattr.h> |
34 | #include <linux/capability.h> | |
35 | #include <linux/unistd.h> | |
36 | #include <linux/mm.h> | |
37 | #include <linux/mman.h> | |
38 | #include <linux/slab.h> | |
39 | #include <linux/pagemap.h> | |
0b24dcb7 | 40 | #include <linux/proc_fs.h> |
1da177e4 | 41 | #include <linux/swap.h> |
1da177e4 LT |
42 | #include <linux/spinlock.h> |
43 | #include <linux/syscalls.h> | |
2a7dba39 | 44 | #include <linux/dcache.h> |
1da177e4 | 45 | #include <linux/file.h> |
9f3acc31 | 46 | #include <linux/fdtable.h> |
1da177e4 LT |
47 | #include <linux/namei.h> |
48 | #include <linux/mount.h> | |
442155c1 DH |
49 | #include <linux/fs_context.h> |
50 | #include <linux/fs_parser.h> | |
1da177e4 LT |
51 | #include <linux/netfilter_ipv4.h> |
52 | #include <linux/netfilter_ipv6.h> | |
53 | #include <linux/tty.h> | |
54 | #include <net/icmp.h> | |
227b60f5 | 55 | #include <net/ip.h> /* for local_port_range[] */ |
1da177e4 | 56 | #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ |
47180068 | 57 | #include <net/inet_connection_sock.h> |
220deb96 | 58 | #include <net/net_namespace.h> |
d621d35e | 59 | #include <net/netlabel.h> |
f5269710 | 60 | #include <linux/uaccess.h> |
1da177e4 | 61 | #include <asm/ioctls.h> |
60063497 | 62 | #include <linux/atomic.h> |
1da177e4 LT |
63 | #include <linux/bitops.h> |
64 | #include <linux/interrupt.h> | |
65 | #include <linux/netdevice.h> /* for network interface checks */ | |
77954983 | 66 | #include <net/netlink.h> |
1da177e4 LT |
67 | #include <linux/tcp.h> |
68 | #include <linux/udp.h> | |
2ee92d46 | 69 | #include <linux/dccp.h> |
d452930f RH |
70 | #include <linux/sctp.h> |
71 | #include <net/sctp/structs.h> | |
1da177e4 LT |
72 | #include <linux/quota.h> |
73 | #include <linux/un.h> /* for Unix socket types */ | |
74 | #include <net/af_unix.h> /* for Unix socket types */ | |
75 | #include <linux/parser.h> | |
76 | #include <linux/nfs_mount.h> | |
77 | #include <net/ipv6.h> | |
78 | #include <linux/hugetlb.h> | |
79 | #include <linux/personality.h> | |
1da177e4 | 80 | #include <linux/audit.h> |
6931dfc9 | 81 | #include <linux/string.h> |
23970741 | 82 | #include <linux/mutex.h> |
f06febc9 | 83 | #include <linux/posix-timers.h> |
00234592 | 84 | #include <linux/syslog.h> |
3486740a | 85 | #include <linux/user_namespace.h> |
44fc7ea0 | 86 | #include <linux/export.h> |
40401530 AV |
87 | #include <linux/msg.h> |
88 | #include <linux/shm.h> | |
ec27c356 | 89 | #include <linux/bpf.h> |
ec882da5 OM |
90 | #include <linux/kernfs.h> |
91 | #include <linux/stringhash.h> /* for hashlen_string() */ | |
e262e32d | 92 | #include <uapi/linux/mount.h> |
ac5656d8 AG |
93 | #include <linux/fsnotify.h> |
94 | #include <linux/fanotify.h> | |
1da177e4 LT |
95 | |
96 | #include "avc.h" | |
97 | #include "objsec.h" | |
98 | #include "netif.h" | |
224dfbd8 | 99 | #include "netnode.h" |
3e112172 | 100 | #include "netport.h" |
409dcf31 | 101 | #include "ibpkey.h" |
d28d1e08 | 102 | #include "xfrm.h" |
c60475bf | 103 | #include "netlabel.h" |
9d57a7f9 | 104 | #include "audit.h" |
7b98a585 | 105 | #include "avc_ss.h" |
1da177e4 | 106 | |
aa8e712c SS |
107 | struct selinux_state selinux_state; |
108 | ||
d621d35e | 109 | /* SECMARK reference count */ |
56a4ca99 | 110 | static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); |
d621d35e | 111 | |
1da177e4 | 112 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
6c5a682e | 113 | static int selinux_enforcing_boot __initdata; |
1da177e4 LT |
114 | |
115 | static int __init enforcing_setup(char *str) | |
116 | { | |
f5269710 | 117 | unsigned long enforcing; |
29707b20 | 118 | if (!kstrtoul(str, 0, &enforcing)) |
aa8e712c | 119 | selinux_enforcing_boot = enforcing ? 1 : 0; |
1da177e4 LT |
120 | return 1; |
121 | } | |
122 | __setup("enforcing=", enforcing_setup); | |
aa8e712c SS |
123 | #else |
124 | #define selinux_enforcing_boot 1 | |
1da177e4 LT |
125 | #endif |
126 | ||
6c5a682e | 127 | int selinux_enabled_boot __initdata = 1; |
1da177e4 | 128 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM |
1da177e4 LT |
129 | static int __init selinux_enabled_setup(char *str) |
130 | { | |
f5269710 | 131 | unsigned long enabled; |
29707b20 | 132 | if (!kstrtoul(str, 0, &enabled)) |
6c5a682e | 133 | selinux_enabled_boot = enabled ? 1 : 0; |
1da177e4 LT |
134 | return 1; |
135 | } | |
136 | __setup("selinux=", selinux_enabled_setup); | |
137 | #endif | |
138 | ||
aa8e712c SS |
139 | static unsigned int selinux_checkreqprot_boot = |
140 | CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE; | |
141 | ||
142 | static int __init checkreqprot_setup(char *str) | |
143 | { | |
144 | unsigned long checkreqprot; | |
145 | ||
e9c38f9f | 146 | if (!kstrtoul(str, 0, &checkreqprot)) { |
aa8e712c | 147 | selinux_checkreqprot_boot = checkreqprot ? 1 : 0; |
e9c38f9f SS |
148 | if (checkreqprot) |
149 | pr_warn("SELinux: checkreqprot set to 1 via kernel parameter. This is deprecated and will be rejected in a future kernel release.\n"); | |
150 | } | |
aa8e712c SS |
151 | return 1; |
152 | } | |
153 | __setup("checkreqprot=", checkreqprot_setup); | |
154 | ||
d621d35e PM |
155 | /** |
156 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
157 | * | |
158 | * Description: | |
159 | * This function checks the SECMARK reference counter to see if any SECMARK | |
160 | * targets are currently configured, if the reference counter is greater than | |
161 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
2be4d74f CP |
162 | * enabled, false (0) if SECMARK is disabled. If the always_check_network |
163 | * policy capability is enabled, SECMARK is always considered enabled. | |
d621d35e PM |
164 | * |
165 | */ | |
166 | static int selinux_secmark_enabled(void) | |
167 | { | |
aa8e712c SS |
168 | return (selinux_policycap_alwaysnetwork() || |
169 | atomic_read(&selinux_secmark_refcount)); | |
2be4d74f CP |
170 | } |
171 | ||
172 | /** | |
173 | * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled | |
174 | * | |
175 | * Description: | |
176 | * This function checks if NetLabel or labeled IPSEC is enabled. Returns true | |
177 | * (1) if any are enabled or false (0) if neither are enabled. If the | |
178 | * always_check_network policy capability is enabled, peer labeling | |
179 | * is always considered enabled. | |
180 | * | |
181 | */ | |
182 | static int selinux_peerlbl_enabled(void) | |
183 | { | |
aa8e712c SS |
184 | return (selinux_policycap_alwaysnetwork() || |
185 | netlbl_enabled() || selinux_xfrm_enabled()); | |
d621d35e PM |
186 | } |
187 | ||
615e51fd PM |
188 | static int selinux_netcache_avc_callback(u32 event) |
189 | { | |
190 | if (event == AVC_CALLBACK_RESET) { | |
191 | sel_netif_flush(); | |
192 | sel_netnode_flush(); | |
193 | sel_netport_flush(); | |
194 | synchronize_net(); | |
195 | } | |
196 | return 0; | |
197 | } | |
198 | ||
8f408ab6 DJ |
199 | static int selinux_lsm_notifier_avc_callback(u32 event) |
200 | { | |
409dcf31 DJ |
201 | if (event == AVC_CALLBACK_RESET) { |
202 | sel_ib_pkey_flush(); | |
42df744c | 203 | call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL); |
409dcf31 | 204 | } |
8f408ab6 DJ |
205 | |
206 | return 0; | |
207 | } | |
208 | ||
d84f4f99 DH |
209 | /* |
210 | * initialise the security for the init task | |
211 | */ | |
212 | static void cred_init_security(void) | |
1da177e4 | 213 | { |
3b11a1de | 214 | struct cred *cred = (struct cred *) current->real_cred; |
1da177e4 LT |
215 | struct task_security_struct *tsec; |
216 | ||
bbd3662a | 217 | tsec = selinux_cred(cred); |
d84f4f99 | 218 | tsec->osid = tsec->sid = SECINITSID_KERNEL; |
1da177e4 LT |
219 | } |
220 | ||
88e67f3b DH |
221 | /* |
222 | * get the security ID of a set of credentials | |
223 | */ | |
224 | static inline u32 cred_sid(const struct cred *cred) | |
225 | { | |
226 | const struct task_security_struct *tsec; | |
227 | ||
0c6cfa62 | 228 | tsec = selinux_cred(cred); |
88e67f3b DH |
229 | return tsec->sid; |
230 | } | |
231 | ||
275bb41e | 232 | /* |
3b11a1de | 233 | * get the objective security ID of a task |
275bb41e DH |
234 | */ |
235 | static inline u32 task_sid(const struct task_struct *task) | |
236 | { | |
275bb41e DH |
237 | u32 sid; |
238 | ||
239 | rcu_read_lock(); | |
88e67f3b | 240 | sid = cred_sid(__task_cred(task)); |
275bb41e DH |
241 | rcu_read_unlock(); |
242 | return sid; | |
243 | } | |
244 | ||
5d226df4 AG |
245 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); |
246 | ||
247 | /* | |
248 | * Try reloading inode security labels that have been marked as invalid. The | |
249 | * @may_sleep parameter indicates when sleeping and thus reloading labels is | |
42059112 | 250 | * allowed; when set to false, returns -ECHILD when the label is |
e9193288 | 251 | * invalid. The @dentry parameter should be set to a dentry of the inode. |
5d226df4 AG |
252 | */ |
253 | static int __inode_security_revalidate(struct inode *inode, | |
e9193288 | 254 | struct dentry *dentry, |
5d226df4 AG |
255 | bool may_sleep) |
256 | { | |
80788c22 | 257 | struct inode_security_struct *isec = selinux_inode(inode); |
5d226df4 AG |
258 | |
259 | might_sleep_if(may_sleep); | |
260 | ||
65cddd50 | 261 | if (selinux_initialized(&selinux_state) && |
aa8e712c | 262 | isec->initialized != LABEL_INITIALIZED) { |
5d226df4 AG |
263 | if (!may_sleep) |
264 | return -ECHILD; | |
265 | ||
266 | /* | |
267 | * Try reloading the inode security label. This will fail if | |
268 | * @opt_dentry is NULL and no dentry for this inode can be | |
269 | * found; in that case, continue using the old label. | |
270 | */ | |
e9193288 | 271 | inode_doinit_with_dentry(inode, dentry); |
5d226df4 AG |
272 | } |
273 | return 0; | |
274 | } | |
275 | ||
5d226df4 AG |
276 | static struct inode_security_struct *inode_security_novalidate(struct inode *inode) |
277 | { | |
80788c22 | 278 | return selinux_inode(inode); |
5d226df4 AG |
279 | } |
280 | ||
281 | static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) | |
282 | { | |
283 | int error; | |
284 | ||
285 | error = __inode_security_revalidate(inode, NULL, !rcu); | |
286 | if (error) | |
287 | return ERR_PTR(error); | |
80788c22 | 288 | return selinux_inode(inode); |
5d226df4 AG |
289 | } |
290 | ||
83da53c5 AG |
291 | /* |
292 | * Get the security label of an inode. | |
293 | */ | |
294 | static struct inode_security_struct *inode_security(struct inode *inode) | |
295 | { | |
5d226df4 | 296 | __inode_security_revalidate(inode, NULL, true); |
80788c22 | 297 | return selinux_inode(inode); |
83da53c5 AG |
298 | } |
299 | ||
2c97165b PM |
300 | static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) |
301 | { | |
302 | struct inode *inode = d_backing_inode(dentry); | |
303 | ||
80788c22 | 304 | return selinux_inode(inode); |
2c97165b PM |
305 | } |
306 | ||
83da53c5 AG |
307 | /* |
308 | * Get the security label of a dentry's backing inode. | |
309 | */ | |
310 | static struct inode_security_struct *backing_inode_security(struct dentry *dentry) | |
311 | { | |
312 | struct inode *inode = d_backing_inode(dentry); | |
313 | ||
5d226df4 | 314 | __inode_security_revalidate(inode, dentry, true); |
80788c22 | 315 | return selinux_inode(inode); |
83da53c5 AG |
316 | } |
317 | ||
1da177e4 LT |
318 | static void inode_free_security(struct inode *inode) |
319 | { | |
80788c22 | 320 | struct inode_security_struct *isec = selinux_inode(inode); |
afb1cbe3 | 321 | struct superblock_security_struct *sbsec; |
1da177e4 | 322 | |
afb1cbe3 CS |
323 | if (!isec) |
324 | return; | |
325 | sbsec = inode->i_sb->s_security; | |
9629d04a WL |
326 | /* |
327 | * As not all inode security structures are in a list, we check for | |
328 | * empty list outside of the lock to make sure that we won't waste | |
329 | * time taking a lock doing nothing. | |
330 | * | |
331 | * The list_del_init() function can be safely called more than once. | |
332 | * It should not be possible for this function to be called with | |
333 | * concurrent list_add(), but for better safety against future changes | |
334 | * in the code, we use list_empty_careful() here. | |
335 | */ | |
336 | if (!list_empty_careful(&isec->list)) { | |
337 | spin_lock(&sbsec->isec_lock); | |
1da177e4 | 338 | list_del_init(&isec->list); |
9629d04a WL |
339 | spin_unlock(&sbsec->isec_lock); |
340 | } | |
1da177e4 LT |
341 | } |
342 | ||
1da177e4 LT |
343 | static void superblock_free_security(struct super_block *sb) |
344 | { | |
345 | struct superblock_security_struct *sbsec = sb->s_security; | |
1da177e4 LT |
346 | sb->s_security = NULL; |
347 | kfree(sbsec); | |
348 | } | |
349 | ||
bd323655 AV |
350 | struct selinux_mnt_opts { |
351 | const char *fscontext, *context, *rootcontext, *defcontext; | |
352 | }; | |
353 | ||
204cc0cc AV |
354 | static void selinux_free_mnt_opts(void *mnt_opts) |
355 | { | |
bd323655 AV |
356 | struct selinux_mnt_opts *opts = mnt_opts; |
357 | kfree(opts->fscontext); | |
358 | kfree(opts->context); | |
359 | kfree(opts->rootcontext); | |
360 | kfree(opts->defcontext); | |
204cc0cc AV |
361 | kfree(opts); |
362 | } | |
363 | ||
1da177e4 | 364 | enum { |
31e87930 | 365 | Opt_error = -1, |
442155c1 DH |
366 | Opt_context = 0, |
367 | Opt_defcontext = 1, | |
1da177e4 | 368 | Opt_fscontext = 2, |
442155c1 DH |
369 | Opt_rootcontext = 3, |
370 | Opt_seclabel = 4, | |
1da177e4 LT |
371 | }; |
372 | ||
da3d76ab | 373 | #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} |
169d68ef AV |
374 | static struct { |
375 | const char *name; | |
376 | int len; | |
377 | int opt; | |
378 | bool has_arg; | |
379 | } tokens[] = { | |
da3d76ab AV |
380 | A(context, true), |
381 | A(fscontext, true), | |
382 | A(defcontext, true), | |
383 | A(rootcontext, true), | |
384 | A(seclabel, false), | |
1da177e4 | 385 | }; |
169d68ef AV |
386 | #undef A |
387 | ||
388 | static int match_opt_prefix(char *s, int l, char **arg) | |
389 | { | |
390 | int i; | |
391 | ||
392 | for (i = 0; i < ARRAY_SIZE(tokens); i++) { | |
393 | size_t len = tokens[i].len; | |
394 | if (len > l || memcmp(s, tokens[i].name, len)) | |
395 | continue; | |
396 | if (tokens[i].has_arg) { | |
397 | if (len == l || s[len] != '=') | |
398 | continue; | |
399 | *arg = s + len + 1; | |
400 | } else if (len != l) | |
401 | continue; | |
402 | return tokens[i].opt; | |
403 | } | |
404 | return Opt_error; | |
405 | } | |
1da177e4 LT |
406 | |
407 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
408 | ||
c312feb2 EP |
409 | static int may_context_mount_sb_relabel(u32 sid, |
410 | struct superblock_security_struct *sbsec, | |
275bb41e | 411 | const struct cred *cred) |
c312feb2 | 412 | { |
0c6cfa62 | 413 | const struct task_security_struct *tsec = selinux_cred(cred); |
c312feb2 EP |
414 | int rc; |
415 | ||
6b6bc620 SS |
416 | rc = avc_has_perm(&selinux_state, |
417 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
418 | FILESYSTEM__RELABELFROM, NULL); |
419 | if (rc) | |
420 | return rc; | |
421 | ||
6b6bc620 SS |
422 | rc = avc_has_perm(&selinux_state, |
423 | tsec->sid, sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
424 | FILESYSTEM__RELABELTO, NULL); |
425 | return rc; | |
426 | } | |
427 | ||
0808925e EP |
428 | static int may_context_mount_inode_relabel(u32 sid, |
429 | struct superblock_security_struct *sbsec, | |
275bb41e | 430 | const struct cred *cred) |
0808925e | 431 | { |
0c6cfa62 | 432 | const struct task_security_struct *tsec = selinux_cred(cred); |
0808925e | 433 | int rc; |
6b6bc620 SS |
434 | rc = avc_has_perm(&selinux_state, |
435 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
436 | FILESYSTEM__RELABELFROM, NULL); |
437 | if (rc) | |
438 | return rc; | |
439 | ||
6b6bc620 SS |
440 | rc = avc_has_perm(&selinux_state, |
441 | sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
442 | FILESYSTEM__ASSOCIATE, NULL); |
443 | return rc; | |
444 | } | |
445 | ||
a83d6dda | 446 | static int selinux_is_genfs_special_handling(struct super_block *sb) |
b43e725d | 447 | { |
a83d6dda OM |
448 | /* Special handling. Genfs but also in-core setxattr handler */ |
449 | return !strcmp(sb->s_type->name, "sysfs") || | |
d5f3a5f6 MS |
450 | !strcmp(sb->s_type->name, "pstore") || |
451 | !strcmp(sb->s_type->name, "debugfs") || | |
a2c7c6fb | 452 | !strcmp(sb->s_type->name, "tracefs") || |
2651225b | 453 | !strcmp(sb->s_type->name, "rootfs") || |
aa8e712c | 454 | (selinux_policycap_cgroupseclabel() && |
2651225b SS |
455 | (!strcmp(sb->s_type->name, "cgroup") || |
456 | !strcmp(sb->s_type->name, "cgroup2"))); | |
b43e725d EP |
457 | } |
458 | ||
a83d6dda OM |
459 | static int selinux_is_sblabel_mnt(struct super_block *sb) |
460 | { | |
461 | struct superblock_security_struct *sbsec = sb->s_security; | |
462 | ||
463 | /* | |
464 | * IMPORTANT: Double-check logic in this function when adding a new | |
465 | * SECURITY_FS_USE_* definition! | |
466 | */ | |
467 | BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); | |
468 | ||
469 | switch (sbsec->behavior) { | |
470 | case SECURITY_FS_USE_XATTR: | |
471 | case SECURITY_FS_USE_TRANS: | |
472 | case SECURITY_FS_USE_TASK: | |
473 | case SECURITY_FS_USE_NATIVE: | |
474 | return 1; | |
475 | ||
476 | case SECURITY_FS_USE_GENFS: | |
477 | return selinux_is_genfs_special_handling(sb); | |
478 | ||
479 | /* Never allow relabeling on context mounts */ | |
480 | case SECURITY_FS_USE_MNTPOINT: | |
481 | case SECURITY_FS_USE_NONE: | |
482 | default: | |
483 | return 0; | |
484 | } | |
485 | } | |
486 | ||
c9180a57 | 487 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 488 | { |
1da177e4 | 489 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 | 490 | struct dentry *root = sb->s_root; |
c6f493d6 | 491 | struct inode *root_inode = d_backing_inode(root); |
c9180a57 | 492 | int rc = 0; |
1da177e4 | 493 | |
c9180a57 EP |
494 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
495 | /* Make sure that the xattr handler exists and that no | |
496 | error other than -ENODATA is returned by getxattr on | |
497 | the root directory. -ENODATA is ok, as this may be | |
498 | the first boot of the SELinux kernel before we have | |
499 | assigned xattr values to the filesystem. */ | |
5d6c3191 | 500 | if (!(root_inode->i_opflags & IOP_XATTR)) { |
c103a91e | 501 | pr_warn("SELinux: (dev %s, type %s) has no " |
29b1deb2 | 502 | "xattr support\n", sb->s_id, sb->s_type->name); |
c9180a57 EP |
503 | rc = -EOPNOTSUPP; |
504 | goto out; | |
505 | } | |
5d6c3191 AG |
506 | |
507 | rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); | |
c9180a57 EP |
508 | if (rc < 0 && rc != -ENODATA) { |
509 | if (rc == -EOPNOTSUPP) | |
c103a91e | 510 | pr_warn("SELinux: (dev %s, type " |
29b1deb2 LT |
511 | "%s) has no security xattr handler\n", |
512 | sb->s_id, sb->s_type->name); | |
c9180a57 | 513 | else |
c103a91e | 514 | pr_warn("SELinux: (dev %s, type " |
29b1deb2 LT |
515 | "%s) getxattr errno %d\n", sb->s_id, |
516 | sb->s_type->name, -rc); | |
c9180a57 EP |
517 | goto out; |
518 | } | |
519 | } | |
1da177e4 | 520 | |
eadcabc6 | 521 | sbsec->flags |= SE_SBINITIALIZED; |
0b4d3452 SM |
522 | |
523 | /* | |
524 | * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply | |
525 | * leave the flag untouched because sb_clone_mnt_opts might be handing | |
526 | * us a superblock that needs the flag to be cleared. | |
527 | */ | |
b43e725d | 528 | if (selinux_is_sblabel_mnt(sb)) |
12f348b9 | 529 | sbsec->flags |= SBLABEL_MNT; |
0b4d3452 SM |
530 | else |
531 | sbsec->flags &= ~SBLABEL_MNT; | |
ddd29ec6 | 532 | |
c9180a57 EP |
533 | /* Initialize the root inode. */ |
534 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 535 | |
c9180a57 EP |
536 | /* Initialize any other inodes associated with the superblock, e.g. |
537 | inodes created prior to initial policy load or inodes created | |
538 | during get_sb by a pseudo filesystem that directly | |
539 | populates itself. */ | |
540 | spin_lock(&sbsec->isec_lock); | |
8d64124a | 541 | while (!list_empty(&sbsec->isec_head)) { |
c9180a57 | 542 | struct inode_security_struct *isec = |
8d64124a | 543 | list_first_entry(&sbsec->isec_head, |
c9180a57 EP |
544 | struct inode_security_struct, list); |
545 | struct inode *inode = isec->inode; | |
923190d3 | 546 | list_del_init(&isec->list); |
c9180a57 EP |
547 | spin_unlock(&sbsec->isec_lock); |
548 | inode = igrab(inode); | |
549 | if (inode) { | |
550 | if (!IS_PRIVATE(inode)) | |
cb89e246 | 551 | inode_doinit_with_dentry(inode, NULL); |
c9180a57 EP |
552 | iput(inode); |
553 | } | |
554 | spin_lock(&sbsec->isec_lock); | |
c9180a57 EP |
555 | } |
556 | spin_unlock(&sbsec->isec_lock); | |
557 | out: | |
558 | return rc; | |
559 | } | |
1da177e4 | 560 | |
c9180a57 EP |
561 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
562 | u32 old_sid, u32 new_sid) | |
563 | { | |
0d90a7ec DQ |
564 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
565 | ||
c9180a57 | 566 | /* check if the old mount command had the same options */ |
0d90a7ec | 567 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
568 | if (!(sbsec->flags & flag) || |
569 | (old_sid != new_sid)) | |
570 | return 1; | |
571 | ||
572 | /* check if we were passed the same options twice, | |
573 | * aka someone passed context=a,context=b | |
574 | */ | |
0d90a7ec DQ |
575 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
576 | if (mnt_flags & flag) | |
c9180a57 EP |
577 | return 1; |
578 | return 0; | |
579 | } | |
e0007529 | 580 | |
bd323655 AV |
581 | static int parse_sid(struct super_block *sb, const char *s, u32 *sid) |
582 | { | |
583 | int rc = security_context_str_to_sid(&selinux_state, s, | |
584 | sid, GFP_KERNEL); | |
585 | if (rc) | |
586 | pr_warn("SELinux: security_context_str_to_sid" | |
587 | "(%s) failed for (dev %s, type %s) errno=%d\n", | |
588 | s, sb->s_id, sb->s_type->name, rc); | |
589 | return rc; | |
590 | } | |
591 | ||
c9180a57 EP |
592 | /* |
593 | * Allow filesystems with binary mount data to explicitly set mount point | |
594 | * labeling information. | |
595 | */ | |
e0007529 | 596 | static int selinux_set_mnt_opts(struct super_block *sb, |
204cc0cc | 597 | void *mnt_opts, |
649f6e77 DQ |
598 | unsigned long kern_flags, |
599 | unsigned long *set_kern_flags) | |
c9180a57 | 600 | { |
275bb41e | 601 | const struct cred *cred = current_cred(); |
c9180a57 | 602 | struct superblock_security_struct *sbsec = sb->s_security; |
83da53c5 | 603 | struct dentry *root = sbsec->sb->s_root; |
bd323655 | 604 | struct selinux_mnt_opts *opts = mnt_opts; |
2c97165b | 605 | struct inode_security_struct *root_isec; |
c9180a57 EP |
606 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
607 | u32 defcontext_sid = 0; | |
bd323655 | 608 | int rc = 0; |
c9180a57 EP |
609 | |
610 | mutex_lock(&sbsec->lock); | |
611 | ||
65cddd50 | 612 | if (!selinux_initialized(&selinux_state)) { |
bd323655 | 613 | if (!opts) { |
c9180a57 EP |
614 | /* Defer initialization until selinux_complete_init, |
615 | after the initial policy is loaded and the security | |
616 | server is ready to handle calls. */ | |
c9180a57 EP |
617 | goto out; |
618 | } | |
619 | rc = -EINVAL; | |
c103a91e | 620 | pr_warn("SELinux: Unable to set superblock options " |
744ba35e | 621 | "before the security server is initialized\n"); |
1da177e4 | 622 | goto out; |
c9180a57 | 623 | } |
649f6e77 DQ |
624 | if (kern_flags && !set_kern_flags) { |
625 | /* Specifying internal flags without providing a place to | |
626 | * place the results is not allowed */ | |
627 | rc = -EINVAL; | |
628 | goto out; | |
629 | } | |
1da177e4 | 630 | |
e0007529 EP |
631 | /* |
632 | * Binary mount data FS will come through this function twice. Once | |
633 | * from an explicit call and once from the generic calls from the vfs. | |
634 | * Since the generic VFS calls will not contain any security mount data | |
635 | * we need to skip the double mount verification. | |
636 | * | |
637 | * This does open a hole in which we will not notice if the first | |
638 | * mount using this sb set explict options and a second mount using | |
639 | * this sb does not set any security options. (The first options | |
640 | * will be used for both mounts) | |
641 | */ | |
0d90a7ec | 642 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
bd323655 | 643 | && !opts) |
f5269710 | 644 | goto out; |
e0007529 | 645 | |
2c97165b PM |
646 | root_isec = backing_inode_security_novalidate(root); |
647 | ||
c9180a57 EP |
648 | /* |
649 | * parse the mount options, check if they are valid sids. | |
650 | * also check if someone is trying to mount the same sb more | |
651 | * than once with different security options. | |
652 | */ | |
bd323655 AV |
653 | if (opts) { |
654 | if (opts->fscontext) { | |
655 | rc = parse_sid(sb, opts->fscontext, &fscontext_sid); | |
656 | if (rc) | |
657 | goto out; | |
c9180a57 EP |
658 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, |
659 | fscontext_sid)) | |
660 | goto out_double_mount; | |
c9180a57 | 661 | sbsec->flags |= FSCONTEXT_MNT; |
bd323655 AV |
662 | } |
663 | if (opts->context) { | |
664 | rc = parse_sid(sb, opts->context, &context_sid); | |
665 | if (rc) | |
666 | goto out; | |
c9180a57 EP |
667 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, |
668 | context_sid)) | |
669 | goto out_double_mount; | |
c9180a57 | 670 | sbsec->flags |= CONTEXT_MNT; |
bd323655 AV |
671 | } |
672 | if (opts->rootcontext) { | |
673 | rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid); | |
674 | if (rc) | |
675 | goto out; | |
c9180a57 EP |
676 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, |
677 | rootcontext_sid)) | |
678 | goto out_double_mount; | |
c9180a57 | 679 | sbsec->flags |= ROOTCONTEXT_MNT; |
bd323655 AV |
680 | } |
681 | if (opts->defcontext) { | |
682 | rc = parse_sid(sb, opts->defcontext, &defcontext_sid); | |
683 | if (rc) | |
684 | goto out; | |
c9180a57 EP |
685 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, |
686 | defcontext_sid)) | |
687 | goto out_double_mount; | |
c9180a57 | 688 | sbsec->flags |= DEFCONTEXT_MNT; |
1da177e4 | 689 | } |
c9180a57 EP |
690 | } |
691 | ||
0d90a7ec | 692 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 693 | /* previously mounted with options, but not on this attempt? */ |
bd323655 | 694 | if ((sbsec->flags & SE_MNTMASK) && !opts) |
c9180a57 EP |
695 | goto out_double_mount; |
696 | rc = 0; | |
697 | goto out; | |
698 | } | |
699 | ||
089be43e | 700 | if (strcmp(sb->s_type->name, "proc") == 0) |
134509d5 SS |
701 | sbsec->flags |= SE_SBPROC | SE_SBGENFS; |
702 | ||
8e014720 | 703 | if (!strcmp(sb->s_type->name, "debugfs") || |
6a391183 | 704 | !strcmp(sb->s_type->name, "tracefs") || |
a20456ae | 705 | !strcmp(sb->s_type->name, "binder") || |
4ca54d3d | 706 | !strcmp(sb->s_type->name, "bpf") || |
b754026b OM |
707 | !strcmp(sb->s_type->name, "pstore")) |
708 | sbsec->flags |= SE_SBGENFS; | |
709 | ||
710 | if (!strcmp(sb->s_type->name, "sysfs") || | |
901ef845 AM |
711 | !strcmp(sb->s_type->name, "cgroup") || |
712 | !strcmp(sb->s_type->name, "cgroup2")) | |
b754026b | 713 | sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; |
c9180a57 | 714 | |
eb9ae686 DQ |
715 | if (!sbsec->behavior) { |
716 | /* | |
717 | * Determine the labeling behavior to use for this | |
718 | * filesystem type. | |
719 | */ | |
aa8e712c | 720 | rc = security_fs_use(&selinux_state, sb); |
eb9ae686 | 721 | if (rc) { |
c103a91e | 722 | pr_warn("%s: security_fs_use(%s) returned %d\n", |
eb9ae686 DQ |
723 | __func__, sb->s_type->name, rc); |
724 | goto out; | |
725 | } | |
c9180a57 | 726 | } |
aad82892 SF |
727 | |
728 | /* | |
01593d32 SS |
729 | * If this is a user namespace mount and the filesystem type is not |
730 | * explicitly whitelisted, then no contexts are allowed on the command | |
731 | * line and security labels must be ignored. | |
aad82892 | 732 | */ |
01593d32 SS |
733 | if (sb->s_user_ns != &init_user_ns && |
734 | strcmp(sb->s_type->name, "tmpfs") && | |
735 | strcmp(sb->s_type->name, "ramfs") && | |
736 | strcmp(sb->s_type->name, "devpts")) { | |
aad82892 SF |
737 | if (context_sid || fscontext_sid || rootcontext_sid || |
738 | defcontext_sid) { | |
739 | rc = -EACCES; | |
740 | goto out; | |
741 | } | |
742 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { | |
743 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; | |
aa8e712c SS |
744 | rc = security_transition_sid(&selinux_state, |
745 | current_sid(), | |
746 | current_sid(), | |
aad82892 SF |
747 | SECCLASS_FILE, NULL, |
748 | &sbsec->mntpoint_sid); | |
749 | if (rc) | |
750 | goto out; | |
751 | } | |
752 | goto out_set_opts; | |
753 | } | |
754 | ||
c9180a57 EP |
755 | /* sets the context of the superblock for the fs being mounted. */ |
756 | if (fscontext_sid) { | |
275bb41e | 757 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
1da177e4 | 758 | if (rc) |
c9180a57 | 759 | goto out; |
1da177e4 | 760 | |
c9180a57 | 761 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
762 | } |
763 | ||
764 | /* | |
765 | * Switch to using mount point labeling behavior. | |
766 | * sets the label used on all file below the mountpoint, and will set | |
767 | * the superblock context if not already set. | |
768 | */ | |
eb9ae686 DQ |
769 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { |
770 | sbsec->behavior = SECURITY_FS_USE_NATIVE; | |
771 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
772 | } | |
773 | ||
c9180a57 EP |
774 | if (context_sid) { |
775 | if (!fscontext_sid) { | |
275bb41e DH |
776 | rc = may_context_mount_sb_relabel(context_sid, sbsec, |
777 | cred); | |
b04ea3ce | 778 | if (rc) |
c9180a57 EP |
779 | goto out; |
780 | sbsec->sid = context_sid; | |
b04ea3ce | 781 | } else { |
275bb41e DH |
782 | rc = may_context_mount_inode_relabel(context_sid, sbsec, |
783 | cred); | |
b04ea3ce | 784 | if (rc) |
c9180a57 | 785 | goto out; |
b04ea3ce | 786 | } |
c9180a57 EP |
787 | if (!rootcontext_sid) |
788 | rootcontext_sid = context_sid; | |
1da177e4 | 789 | |
c9180a57 | 790 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 791 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
792 | } |
793 | ||
c9180a57 | 794 | if (rootcontext_sid) { |
275bb41e DH |
795 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
796 | cred); | |
0808925e | 797 | if (rc) |
c9180a57 | 798 | goto out; |
0808925e | 799 | |
c9180a57 | 800 | root_isec->sid = rootcontext_sid; |
6f3be9f5 | 801 | root_isec->initialized = LABEL_INITIALIZED; |
0808925e EP |
802 | } |
803 | ||
c9180a57 | 804 | if (defcontext_sid) { |
eb9ae686 DQ |
805 | if (sbsec->behavior != SECURITY_FS_USE_XATTR && |
806 | sbsec->behavior != SECURITY_FS_USE_NATIVE) { | |
c9180a57 | 807 | rc = -EINVAL; |
c103a91e | 808 | pr_warn("SELinux: defcontext option is " |
c9180a57 EP |
809 | "invalid for this filesystem type\n"); |
810 | goto out; | |
1da177e4 LT |
811 | } |
812 | ||
c9180a57 EP |
813 | if (defcontext_sid != sbsec->def_sid) { |
814 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
275bb41e | 815 | sbsec, cred); |
c9180a57 EP |
816 | if (rc) |
817 | goto out; | |
818 | } | |
1da177e4 | 819 | |
c9180a57 | 820 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
821 | } |
822 | ||
aad82892 | 823 | out_set_opts: |
c9180a57 | 824 | rc = sb_finish_set_opts(sb); |
1da177e4 | 825 | out: |
c9180a57 | 826 | mutex_unlock(&sbsec->lock); |
1da177e4 | 827 | return rc; |
c9180a57 EP |
828 | out_double_mount: |
829 | rc = -EINVAL; | |
c103a91e | 830 | pr_warn("SELinux: mount invalid. Same superblock, different " |
bd323655 AV |
831 | "security settings for (dev %s, type %s)\n", sb->s_id, |
832 | sb->s_type->name); | |
c9180a57 | 833 | goto out; |
1da177e4 LT |
834 | } |
835 | ||
094f7b69 JL |
836 | static int selinux_cmp_sb_context(const struct super_block *oldsb, |
837 | const struct super_block *newsb) | |
838 | { | |
839 | struct superblock_security_struct *old = oldsb->s_security; | |
840 | struct superblock_security_struct *new = newsb->s_security; | |
841 | char oldflags = old->flags & SE_MNTMASK; | |
842 | char newflags = new->flags & SE_MNTMASK; | |
843 | ||
844 | if (oldflags != newflags) | |
845 | goto mismatch; | |
846 | if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) | |
847 | goto mismatch; | |
848 | if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) | |
849 | goto mismatch; | |
850 | if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) | |
851 | goto mismatch; | |
852 | if (oldflags & ROOTCONTEXT_MNT) { | |
83da53c5 AG |
853 | struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); |
854 | struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); | |
094f7b69 JL |
855 | if (oldroot->sid != newroot->sid) |
856 | goto mismatch; | |
857 | } | |
858 | return 0; | |
859 | mismatch: | |
c103a91e | 860 | pr_warn("SELinux: mount invalid. Same superblock, " |
094f7b69 JL |
861 | "different security settings for (dev %s, " |
862 | "type %s)\n", newsb->s_id, newsb->s_type->name); | |
863 | return -EBUSY; | |
864 | } | |
865 | ||
866 | static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, | |
0b4d3452 SM |
867 | struct super_block *newsb, |
868 | unsigned long kern_flags, | |
869 | unsigned long *set_kern_flags) | |
1da177e4 | 870 | { |
0b4d3452 | 871 | int rc = 0; |
c9180a57 EP |
872 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
873 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 874 | |
c9180a57 EP |
875 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
876 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
877 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 878 | |
0f5e6420 EP |
879 | /* |
880 | * if the parent was able to be mounted it clearly had no special lsm | |
e8c26255 | 881 | * mount options. thus we can safely deal with this superblock later |
0f5e6420 | 882 | */ |
65cddd50 | 883 | if (!selinux_initialized(&selinux_state)) |
094f7b69 | 884 | return 0; |
c9180a57 | 885 | |
0b4d3452 SM |
886 | /* |
887 | * Specifying internal flags without providing a place to | |
888 | * place the results is not allowed. | |
889 | */ | |
890 | if (kern_flags && !set_kern_flags) | |
891 | return -EINVAL; | |
892 | ||
c9180a57 | 893 | /* how can we clone if the old one wasn't set up?? */ |
0d90a7ec | 894 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
c9180a57 | 895 | |
094f7b69 | 896 | /* if fs is reusing a sb, make sure that the contexts match */ |
3815a245 BF |
897 | if (newsbsec->flags & SE_SBINITIALIZED) { |
898 | if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) | |
899 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
094f7b69 | 900 | return selinux_cmp_sb_context(oldsb, newsb); |
3815a245 | 901 | } |
5a552617 | 902 | |
c9180a57 EP |
903 | mutex_lock(&newsbsec->lock); |
904 | ||
905 | newsbsec->flags = oldsbsec->flags; | |
906 | ||
907 | newsbsec->sid = oldsbsec->sid; | |
908 | newsbsec->def_sid = oldsbsec->def_sid; | |
909 | newsbsec->behavior = oldsbsec->behavior; | |
910 | ||
0b4d3452 SM |
911 | if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && |
912 | !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { | |
aa8e712c | 913 | rc = security_fs_use(&selinux_state, newsb); |
0b4d3452 SM |
914 | if (rc) |
915 | goto out; | |
916 | } | |
917 | ||
918 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { | |
919 | newsbsec->behavior = SECURITY_FS_USE_NATIVE; | |
920 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
921 | } | |
922 | ||
c9180a57 EP |
923 | if (set_context) { |
924 | u32 sid = oldsbsec->mntpoint_sid; | |
925 | ||
926 | if (!set_fscontext) | |
927 | newsbsec->sid = sid; | |
928 | if (!set_rootcontext) { | |
83da53c5 | 929 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); |
c9180a57 EP |
930 | newisec->sid = sid; |
931 | } | |
932 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 933 | } |
c9180a57 | 934 | if (set_rootcontext) { |
83da53c5 AG |
935 | const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); |
936 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); | |
1da177e4 | 937 | |
c9180a57 | 938 | newisec->sid = oldisec->sid; |
1da177e4 LT |
939 | } |
940 | ||
c9180a57 | 941 | sb_finish_set_opts(newsb); |
0b4d3452 | 942 | out: |
c9180a57 | 943 | mutex_unlock(&newsbsec->lock); |
0b4d3452 | 944 | return rc; |
c9180a57 EP |
945 | } |
946 | ||
ba641862 | 947 | static int selinux_add_opt(int token, const char *s, void **mnt_opts) |
c9180a57 | 948 | { |
ba641862 | 949 | struct selinux_mnt_opts *opts = *mnt_opts; |
1da177e4 | 950 | |
da3d76ab | 951 | if (token == Opt_seclabel) /* eaten and completely ignored */ |
169d68ef | 952 | return 0; |
e0007529 | 953 | |
ba641862 AV |
954 | if (!opts) { |
955 | opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); | |
956 | if (!opts) | |
957 | return -ENOMEM; | |
958 | *mnt_opts = opts; | |
c9180a57 | 959 | } |
ba641862 AV |
960 | if (!s) |
961 | return -ENOMEM; | |
962 | switch (token) { | |
963 | case Opt_context: | |
964 | if (opts->context || opts->defcontext) | |
965 | goto Einval; | |
966 | opts->context = s; | |
967 | break; | |
968 | case Opt_fscontext: | |
969 | if (opts->fscontext) | |
970 | goto Einval; | |
971 | opts->fscontext = s; | |
972 | break; | |
973 | case Opt_rootcontext: | |
974 | if (opts->rootcontext) | |
975 | goto Einval; | |
976 | opts->rootcontext = s; | |
977 | break; | |
978 | case Opt_defcontext: | |
979 | if (opts->context || opts->defcontext) | |
980 | goto Einval; | |
981 | opts->defcontext = s; | |
982 | break; | |
c9180a57 | 983 | } |
e0007529 | 984 | return 0; |
ba641862 AV |
985 | Einval: |
986 | pr_warn(SEL_MOUNT_FAIL_MSG); | |
ba641862 | 987 | return -EINVAL; |
1da177e4 | 988 | } |
e0007529 | 989 | |
757cbe59 AV |
990 | static int selinux_add_mnt_opt(const char *option, const char *val, int len, |
991 | void **mnt_opts) | |
c9180a57 | 992 | { |
757cbe59 AV |
993 | int token = Opt_error; |
994 | int rc, i; | |
e0007529 | 995 | |
757cbe59 AV |
996 | for (i = 0; i < ARRAY_SIZE(tokens); i++) { |
997 | if (strcmp(option, tokens[i].name) == 0) { | |
998 | token = tokens[i].opt; | |
999 | break; | |
169d68ef | 1000 | } |
757cbe59 | 1001 | } |
e0007529 | 1002 | |
757cbe59 AV |
1003 | if (token == Opt_error) |
1004 | return -EINVAL; | |
e0007529 | 1005 | |
e2e0e097 | 1006 | if (token != Opt_seclabel) { |
757cbe59 | 1007 | val = kmemdup_nul(val, len, GFP_KERNEL); |
e2e0e097 GZ |
1008 | if (!val) { |
1009 | rc = -ENOMEM; | |
1010 | goto free_opt; | |
1011 | } | |
1012 | } | |
757cbe59 AV |
1013 | rc = selinux_add_opt(token, val, mnt_opts); |
1014 | if (unlikely(rc)) { | |
1015 | kfree(val); | |
e2e0e097 GZ |
1016 | goto free_opt; |
1017 | } | |
1018 | return rc; | |
1019 | ||
1020 | free_opt: | |
1021 | if (*mnt_opts) { | |
1022 | selinux_free_mnt_opts(*mnt_opts); | |
1023 | *mnt_opts = NULL; | |
1da177e4 | 1024 | } |
e0007529 EP |
1025 | return rc; |
1026 | } | |
1da177e4 | 1027 | |
e3489f89 | 1028 | static int show_sid(struct seq_file *m, u32 sid) |
2069f457 | 1029 | { |
e3489f89 AV |
1030 | char *context = NULL; |
1031 | u32 len; | |
1032 | int rc; | |
11689d47 | 1033 | |
e3489f89 AV |
1034 | rc = security_sid_to_context(&selinux_state, sid, |
1035 | &context, &len); | |
1036 | if (!rc) { | |
1037 | bool has_comma = context && strchr(context, ','); | |
2069f457 | 1038 | |
442155c1 | 1039 | seq_putc(m, '='); |
2069f457 EP |
1040 | if (has_comma) |
1041 | seq_putc(m, '\"'); | |
e3489f89 | 1042 | seq_escape(m, context, "\"\n\\"); |
2069f457 EP |
1043 | if (has_comma) |
1044 | seq_putc(m, '\"'); | |
1045 | } | |
e3489f89 AV |
1046 | kfree(context); |
1047 | return rc; | |
2069f457 EP |
1048 | } |
1049 | ||
1050 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1051 | { | |
e3489f89 | 1052 | struct superblock_security_struct *sbsec = sb->s_security; |
2069f457 EP |
1053 | int rc; |
1054 | ||
e3489f89 AV |
1055 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
1056 | return 0; | |
2069f457 | 1057 | |
65cddd50 | 1058 | if (!selinux_initialized(&selinux_state)) |
e3489f89 | 1059 | return 0; |
2069f457 | 1060 | |
e3489f89 AV |
1061 | if (sbsec->flags & FSCONTEXT_MNT) { |
1062 | seq_putc(m, ','); | |
1063 | seq_puts(m, FSCONTEXT_STR); | |
1064 | rc = show_sid(m, sbsec->sid); | |
1065 | if (rc) | |
1066 | return rc; | |
1067 | } | |
1068 | if (sbsec->flags & CONTEXT_MNT) { | |
1069 | seq_putc(m, ','); | |
1070 | seq_puts(m, CONTEXT_STR); | |
1071 | rc = show_sid(m, sbsec->mntpoint_sid); | |
1072 | if (rc) | |
1073 | return rc; | |
1074 | } | |
1075 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
1076 | seq_putc(m, ','); | |
1077 | seq_puts(m, DEFCONTEXT_STR); | |
1078 | rc = show_sid(m, sbsec->def_sid); | |
1079 | if (rc) | |
1080 | return rc; | |
1081 | } | |
1082 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
1083 | struct dentry *root = sbsec->sb->s_root; | |
1084 | struct inode_security_struct *isec = backing_inode_security(root); | |
1085 | seq_putc(m, ','); | |
1086 | seq_puts(m, ROOTCONTEXT_STR); | |
1087 | rc = show_sid(m, isec->sid); | |
1088 | if (rc) | |
1089 | return rc; | |
1090 | } | |
1091 | if (sbsec->flags & SBLABEL_MNT) { | |
1092 | seq_putc(m, ','); | |
442155c1 | 1093 | seq_puts(m, SECLABEL_STR); |
e3489f89 AV |
1094 | } |
1095 | return 0; | |
2069f457 EP |
1096 | } |
1097 | ||
1da177e4 LT |
1098 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1099 | { | |
1100 | switch (mode & S_IFMT) { | |
1101 | case S_IFSOCK: | |
1102 | return SECCLASS_SOCK_FILE; | |
1103 | case S_IFLNK: | |
1104 | return SECCLASS_LNK_FILE; | |
1105 | case S_IFREG: | |
1106 | return SECCLASS_FILE; | |
1107 | case S_IFBLK: | |
1108 | return SECCLASS_BLK_FILE; | |
1109 | case S_IFDIR: | |
1110 | return SECCLASS_DIR; | |
1111 | case S_IFCHR: | |
1112 | return SECCLASS_CHR_FILE; | |
1113 | case S_IFIFO: | |
1114 | return SECCLASS_FIFO_FILE; | |
1115 | ||
1116 | } | |
1117 | ||
1118 | return SECCLASS_FILE; | |
1119 | } | |
1120 | ||
13402580 JM |
1121 | static inline int default_protocol_stream(int protocol) |
1122 | { | |
1123 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1124 | } | |
1125 | ||
1126 | static inline int default_protocol_dgram(int protocol) | |
1127 | { | |
1128 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1129 | } | |
1130 | ||
1da177e4 LT |
1131 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1132 | { | |
aa8e712c | 1133 | int extsockclass = selinux_policycap_extsockclass(); |
da69a530 | 1134 | |
1da177e4 LT |
1135 | switch (family) { |
1136 | case PF_UNIX: | |
1137 | switch (type) { | |
1138 | case SOCK_STREAM: | |
1139 | case SOCK_SEQPACKET: | |
1140 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1141 | case SOCK_DGRAM: | |
2a764b52 | 1142 | case SOCK_RAW: |
1da177e4 LT |
1143 | return SECCLASS_UNIX_DGRAM_SOCKET; |
1144 | } | |
1145 | break; | |
1146 | case PF_INET: | |
1147 | case PF_INET6: | |
1148 | switch (type) { | |
1149 | case SOCK_STREAM: | |
da69a530 | 1150 | case SOCK_SEQPACKET: |
13402580 JM |
1151 | if (default_protocol_stream(protocol)) |
1152 | return SECCLASS_TCP_SOCKET; | |
da69a530 SS |
1153 | else if (extsockclass && protocol == IPPROTO_SCTP) |
1154 | return SECCLASS_SCTP_SOCKET; | |
13402580 JM |
1155 | else |
1156 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1157 | case SOCK_DGRAM: |
13402580 JM |
1158 | if (default_protocol_dgram(protocol)) |
1159 | return SECCLASS_UDP_SOCKET; | |
ef37979a SS |
1160 | else if (extsockclass && (protocol == IPPROTO_ICMP || |
1161 | protocol == IPPROTO_ICMPV6)) | |
da69a530 | 1162 | return SECCLASS_ICMP_SOCKET; |
13402580 JM |
1163 | else |
1164 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1165 | case SOCK_DCCP: |
1166 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1167 | default: |
1da177e4 LT |
1168 | return SECCLASS_RAWIP_SOCKET; |
1169 | } | |
1170 | break; | |
1171 | case PF_NETLINK: | |
1172 | switch (protocol) { | |
1173 | case NETLINK_ROUTE: | |
1174 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
7f1fb60c | 1175 | case NETLINK_SOCK_DIAG: |
1da177e4 LT |
1176 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1177 | case NETLINK_NFLOG: | |
1178 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1179 | case NETLINK_XFRM: | |
1180 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1181 | case NETLINK_SELINUX: | |
1182 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
6c6d2e9b SS |
1183 | case NETLINK_ISCSI: |
1184 | return SECCLASS_NETLINK_ISCSI_SOCKET; | |
1da177e4 LT |
1185 | case NETLINK_AUDIT: |
1186 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
6c6d2e9b SS |
1187 | case NETLINK_FIB_LOOKUP: |
1188 | return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; | |
1189 | case NETLINK_CONNECTOR: | |
1190 | return SECCLASS_NETLINK_CONNECTOR_SOCKET; | |
1191 | case NETLINK_NETFILTER: | |
1192 | return SECCLASS_NETLINK_NETFILTER_SOCKET; | |
1da177e4 LT |
1193 | case NETLINK_DNRTMSG: |
1194 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1195 | case NETLINK_KOBJECT_UEVENT: |
1196 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
6c6d2e9b SS |
1197 | case NETLINK_GENERIC: |
1198 | return SECCLASS_NETLINK_GENERIC_SOCKET; | |
1199 | case NETLINK_SCSITRANSPORT: | |
1200 | return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; | |
1201 | case NETLINK_RDMA: | |
1202 | return SECCLASS_NETLINK_RDMA_SOCKET; | |
1203 | case NETLINK_CRYPTO: | |
1204 | return SECCLASS_NETLINK_CRYPTO_SOCKET; | |
1da177e4 LT |
1205 | default: |
1206 | return SECCLASS_NETLINK_SOCKET; | |
1207 | } | |
1208 | case PF_PACKET: | |
1209 | return SECCLASS_PACKET_SOCKET; | |
1210 | case PF_KEY: | |
1211 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1212 | case PF_APPLETALK: |
1213 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1214 | } |
1215 | ||
da69a530 SS |
1216 | if (extsockclass) { |
1217 | switch (family) { | |
1218 | case PF_AX25: | |
1219 | return SECCLASS_AX25_SOCKET; | |
1220 | case PF_IPX: | |
1221 | return SECCLASS_IPX_SOCKET; | |
1222 | case PF_NETROM: | |
1223 | return SECCLASS_NETROM_SOCKET; | |
da69a530 SS |
1224 | case PF_ATMPVC: |
1225 | return SECCLASS_ATMPVC_SOCKET; | |
1226 | case PF_X25: | |
1227 | return SECCLASS_X25_SOCKET; | |
1228 | case PF_ROSE: | |
1229 | return SECCLASS_ROSE_SOCKET; | |
1230 | case PF_DECnet: | |
1231 | return SECCLASS_DECNET_SOCKET; | |
1232 | case PF_ATMSVC: | |
1233 | return SECCLASS_ATMSVC_SOCKET; | |
1234 | case PF_RDS: | |
1235 | return SECCLASS_RDS_SOCKET; | |
1236 | case PF_IRDA: | |
1237 | return SECCLASS_IRDA_SOCKET; | |
1238 | case PF_PPPOX: | |
1239 | return SECCLASS_PPPOX_SOCKET; | |
1240 | case PF_LLC: | |
1241 | return SECCLASS_LLC_SOCKET; | |
da69a530 SS |
1242 | case PF_CAN: |
1243 | return SECCLASS_CAN_SOCKET; | |
1244 | case PF_TIPC: | |
1245 | return SECCLASS_TIPC_SOCKET; | |
1246 | case PF_BLUETOOTH: | |
1247 | return SECCLASS_BLUETOOTH_SOCKET; | |
1248 | case PF_IUCV: | |
1249 | return SECCLASS_IUCV_SOCKET; | |
1250 | case PF_RXRPC: | |
1251 | return SECCLASS_RXRPC_SOCKET; | |
1252 | case PF_ISDN: | |
1253 | return SECCLASS_ISDN_SOCKET; | |
1254 | case PF_PHONET: | |
1255 | return SECCLASS_PHONET_SOCKET; | |
1256 | case PF_IEEE802154: | |
1257 | return SECCLASS_IEEE802154_SOCKET; | |
1258 | case PF_CAIF: | |
1259 | return SECCLASS_CAIF_SOCKET; | |
1260 | case PF_ALG: | |
1261 | return SECCLASS_ALG_SOCKET; | |
1262 | case PF_NFC: | |
1263 | return SECCLASS_NFC_SOCKET; | |
1264 | case PF_VSOCK: | |
1265 | return SECCLASS_VSOCK_SOCKET; | |
1266 | case PF_KCM: | |
1267 | return SECCLASS_KCM_SOCKET; | |
1268 | case PF_QIPCRTR: | |
1269 | return SECCLASS_QIPCRTR_SOCKET; | |
3051bf36 LT |
1270 | case PF_SMC: |
1271 | return SECCLASS_SMC_SOCKET; | |
68e8b849 BT |
1272 | case PF_XDP: |
1273 | return SECCLASS_XDP_SOCKET; | |
1274 | #if PF_MAX > 45 | |
da69a530 SS |
1275 | #error New address family defined, please update this function. |
1276 | #endif | |
1277 | } | |
1278 | } | |
1279 | ||
1da177e4 LT |
1280 | return SECCLASS_SOCKET; |
1281 | } | |
1282 | ||
134509d5 SS |
1283 | static int selinux_genfs_get_sid(struct dentry *dentry, |
1284 | u16 tclass, | |
1285 | u16 flags, | |
1286 | u32 *sid) | |
1da177e4 | 1287 | { |
8e6c9693 | 1288 | int rc; |
fc64005c | 1289 | struct super_block *sb = dentry->d_sb; |
8e6c9693 | 1290 | char *buffer, *path; |
1da177e4 | 1291 | |
828dfe1d | 1292 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1293 | if (!buffer) |
1294 | return -ENOMEM; | |
1295 | ||
8e6c9693 LAG |
1296 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1297 | if (IS_ERR(path)) | |
1298 | rc = PTR_ERR(path); | |
1299 | else { | |
134509d5 SS |
1300 | if (flags & SE_SBPROC) { |
1301 | /* each process gets a /proc/PID/ entry. Strip off the | |
1302 | * PID part to get a valid selinux labeling. | |
1303 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1304 | while (path[1] >= '0' && path[1] <= '9') { | |
1305 | path[1] = '/'; | |
1306 | path++; | |
1307 | } | |
8e6c9693 | 1308 | } |
aa8e712c SS |
1309 | rc = security_genfs_sid(&selinux_state, sb->s_type->name, |
1310 | path, tclass, sid); | |
7bb185ed SS |
1311 | if (rc == -ENOENT) { |
1312 | /* No match in policy, mark as unlabeled. */ | |
1313 | *sid = SECINITSID_UNLABELED; | |
1314 | rc = 0; | |
1315 | } | |
1da177e4 | 1316 | } |
1da177e4 LT |
1317 | free_page((unsigned long)buffer); |
1318 | return rc; | |
1319 | } | |
1da177e4 | 1320 | |
b754026b OM |
1321 | static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, |
1322 | u32 def_sid, u32 *sid) | |
1323 | { | |
1324 | #define INITCONTEXTLEN 255 | |
1325 | char *context; | |
1326 | unsigned int len; | |
1327 | int rc; | |
1328 | ||
1329 | len = INITCONTEXTLEN; | |
1330 | context = kmalloc(len + 1, GFP_NOFS); | |
1331 | if (!context) | |
1332 | return -ENOMEM; | |
1333 | ||
1334 | context[len] = '\0'; | |
1335 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); | |
1336 | if (rc == -ERANGE) { | |
1337 | kfree(context); | |
1338 | ||
1339 | /* Need a larger buffer. Query for the right size. */ | |
1340 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); | |
1341 | if (rc < 0) | |
1342 | return rc; | |
1343 | ||
1344 | len = rc; | |
1345 | context = kmalloc(len + 1, GFP_NOFS); | |
1346 | if (!context) | |
1347 | return -ENOMEM; | |
1348 | ||
1349 | context[len] = '\0'; | |
1350 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, | |
1351 | context, len); | |
1352 | } | |
1353 | if (rc < 0) { | |
1354 | kfree(context); | |
1355 | if (rc != -ENODATA) { | |
1356 | pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", | |
1357 | __func__, -rc, inode->i_sb->s_id, inode->i_ino); | |
1358 | return rc; | |
1359 | } | |
1360 | *sid = def_sid; | |
1361 | return 0; | |
1362 | } | |
1363 | ||
1364 | rc = security_context_to_sid_default(&selinux_state, context, rc, sid, | |
1365 | def_sid, GFP_NOFS); | |
1366 | if (rc) { | |
1367 | char *dev = inode->i_sb->s_id; | |
1368 | unsigned long ino = inode->i_ino; | |
1369 | ||
1370 | if (rc == -EINVAL) { | |
1371 | 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", | |
1372 | ino, dev, context); | |
1373 | } else { | |
1374 | pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", | |
1375 | __func__, context, -rc, dev, ino); | |
1376 | } | |
1377 | } | |
1378 | kfree(context); | |
1379 | return 0; | |
1380 | } | |
1381 | ||
1da177e4 LT |
1382 | /* The inode's security attributes must be initialized before first use. */ |
1383 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1384 | { | |
1385 | struct superblock_security_struct *sbsec = NULL; | |
80788c22 | 1386 | struct inode_security_struct *isec = selinux_inode(inode); |
9287aed2 AG |
1387 | u32 task_sid, sid = 0; |
1388 | u16 sclass; | |
1da177e4 | 1389 | struct dentry *dentry; |
1da177e4 | 1390 | int rc = 0; |
1da177e4 | 1391 | |
6f3be9f5 | 1392 | if (isec->initialized == LABEL_INITIALIZED) |
13457d07 | 1393 | return 0; |
1da177e4 | 1394 | |
9287aed2 | 1395 | spin_lock(&isec->lock); |
6f3be9f5 | 1396 | if (isec->initialized == LABEL_INITIALIZED) |
23970741 | 1397 | goto out_unlock; |
1da177e4 | 1398 | |
13457d07 AG |
1399 | if (isec->sclass == SECCLASS_FILE) |
1400 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1401 | ||
1da177e4 | 1402 | sbsec = inode->i_sb->s_security; |
0d90a7ec | 1403 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1404 | /* Defer initialization until selinux_complete_init, |
1405 | after the initial policy is loaded and the security | |
1406 | server is ready to handle calls. */ | |
1407 | spin_lock(&sbsec->isec_lock); | |
1408 | if (list_empty(&isec->list)) | |
1409 | list_add(&isec->list, &sbsec->isec_head); | |
1410 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1411 | goto out_unlock; |
1da177e4 LT |
1412 | } |
1413 | ||
9287aed2 AG |
1414 | sclass = isec->sclass; |
1415 | task_sid = isec->task_sid; | |
1416 | sid = isec->sid; | |
1417 | isec->initialized = LABEL_PENDING; | |
1418 | spin_unlock(&isec->lock); | |
1419 | ||
1da177e4 | 1420 | switch (sbsec->behavior) { |
eb9ae686 DQ |
1421 | case SECURITY_FS_USE_NATIVE: |
1422 | break; | |
1da177e4 | 1423 | case SECURITY_FS_USE_XATTR: |
5d6c3191 | 1424 | if (!(inode->i_opflags & IOP_XATTR)) { |
9287aed2 | 1425 | sid = sbsec->def_sid; |
1da177e4 LT |
1426 | break; |
1427 | } | |
1da177e4 LT |
1428 | /* Need a dentry, since the xattr API requires one. |
1429 | Life would be simpler if we could just pass the inode. */ | |
1430 | if (opt_dentry) { | |
1431 | /* Called from d_instantiate or d_splice_alias. */ | |
1432 | dentry = dget(opt_dentry); | |
1433 | } else { | |
b127125d AV |
1434 | /* |
1435 | * Called from selinux_complete_init, try to find a dentry. | |
1436 | * Some filesystems really want a connected one, so try | |
1437 | * that first. We could split SECURITY_FS_USE_XATTR in | |
1438 | * two, depending upon that... | |
1439 | */ | |
1da177e4 | 1440 | dentry = d_find_alias(inode); |
b127125d AV |
1441 | if (!dentry) |
1442 | dentry = d_find_any_alias(inode); | |
1da177e4 LT |
1443 | } |
1444 | if (!dentry) { | |
df7f54c0 EP |
1445 | /* |
1446 | * this is can be hit on boot when a file is accessed | |
1447 | * before the policy is loaded. When we load policy we | |
1448 | * may find inodes that have no dentry on the | |
1449 | * sbsec->isec_head list. No reason to complain as these | |
1450 | * will get fixed up the next time we go through | |
1451 | * inode_doinit with a dentry, before these inodes could | |
1452 | * be used again by userspace. | |
1453 | */ | |
9287aed2 | 1454 | goto out; |
1da177e4 LT |
1455 | } |
1456 | ||
b754026b OM |
1457 | rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, |
1458 | &sid); | |
1da177e4 | 1459 | dput(dentry); |
b754026b OM |
1460 | if (rc) |
1461 | goto out; | |
1da177e4 LT |
1462 | break; |
1463 | case SECURITY_FS_USE_TASK: | |
9287aed2 | 1464 | sid = task_sid; |
1da177e4 LT |
1465 | break; |
1466 | case SECURITY_FS_USE_TRANS: | |
1467 | /* Default to the fs SID. */ | |
9287aed2 | 1468 | sid = sbsec->sid; |
1da177e4 LT |
1469 | |
1470 | /* Try to obtain a transition SID. */ | |
aa8e712c SS |
1471 | rc = security_transition_sid(&selinux_state, task_sid, sid, |
1472 | sclass, NULL, &sid); | |
1da177e4 | 1473 | if (rc) |
9287aed2 | 1474 | goto out; |
1da177e4 | 1475 | break; |
c312feb2 | 1476 | case SECURITY_FS_USE_MNTPOINT: |
9287aed2 | 1477 | sid = sbsec->mntpoint_sid; |
c312feb2 | 1478 | break; |
1da177e4 | 1479 | default: |
c312feb2 | 1480 | /* Default to the fs superblock SID. */ |
9287aed2 | 1481 | sid = sbsec->sid; |
1da177e4 | 1482 | |
7470d0d1 CG |
1483 | if ((sbsec->flags & SE_SBGENFS) && |
1484 | (!S_ISLNK(inode->i_mode) || | |
1485 | selinux_policycap_genfs_seclabel_symlinks())) { | |
f64410ec PM |
1486 | /* We must have a dentry to determine the label on |
1487 | * procfs inodes */ | |
b127125d | 1488 | if (opt_dentry) { |
f64410ec PM |
1489 | /* Called from d_instantiate or |
1490 | * d_splice_alias. */ | |
1491 | dentry = dget(opt_dentry); | |
b127125d | 1492 | } else { |
f64410ec | 1493 | /* Called from selinux_complete_init, try to |
b127125d AV |
1494 | * find a dentry. Some filesystems really want |
1495 | * a connected one, so try that first. | |
1496 | */ | |
f64410ec | 1497 | dentry = d_find_alias(inode); |
b127125d AV |
1498 | if (!dentry) |
1499 | dentry = d_find_any_alias(inode); | |
1500 | } | |
f64410ec PM |
1501 | /* |
1502 | * This can be hit on boot when a file is accessed | |
1503 | * before the policy is loaded. When we load policy we | |
1504 | * may find inodes that have no dentry on the | |
1505 | * sbsec->isec_head list. No reason to complain as | |
1506 | * these will get fixed up the next time we go through | |
1507 | * inode_doinit() with a dentry, before these inodes | |
1508 | * could be used again by userspace. | |
1509 | */ | |
1510 | if (!dentry) | |
9287aed2 AG |
1511 | goto out; |
1512 | rc = selinux_genfs_get_sid(dentry, sclass, | |
134509d5 | 1513 | sbsec->flags, &sid); |
b754026b OM |
1514 | if (rc) { |
1515 | dput(dentry); | |
9287aed2 | 1516 | goto out; |
b754026b OM |
1517 | } |
1518 | ||
1519 | if ((sbsec->flags & SE_SBGENFS_XATTR) && | |
1520 | (inode->i_opflags & IOP_XATTR)) { | |
1521 | rc = inode_doinit_use_xattr(inode, dentry, | |
1522 | sid, &sid); | |
1523 | if (rc) { | |
1524 | dput(dentry); | |
1525 | goto out; | |
1526 | } | |
1527 | } | |
1528 | dput(dentry); | |
1da177e4 LT |
1529 | } |
1530 | break; | |
1531 | } | |
1532 | ||
9287aed2 AG |
1533 | out: |
1534 | spin_lock(&isec->lock); | |
1535 | if (isec->initialized == LABEL_PENDING) { | |
1536 | if (!sid || rc) { | |
1537 | isec->initialized = LABEL_INVALID; | |
1538 | goto out_unlock; | |
1539 | } | |
1540 | ||
1541 | isec->initialized = LABEL_INITIALIZED; | |
1542 | isec->sid = sid; | |
1543 | } | |
1da177e4 | 1544 | |
23970741 | 1545 | out_unlock: |
9287aed2 | 1546 | spin_unlock(&isec->lock); |
1da177e4 LT |
1547 | return rc; |
1548 | } | |
1549 | ||
1550 | /* Convert a Linux signal to an access vector. */ | |
1551 | static inline u32 signal_to_av(int sig) | |
1552 | { | |
1553 | u32 perm = 0; | |
1554 | ||
1555 | switch (sig) { | |
1556 | case SIGCHLD: | |
1557 | /* Commonly granted from child to parent. */ | |
1558 | perm = PROCESS__SIGCHLD; | |
1559 | break; | |
1560 | case SIGKILL: | |
1561 | /* Cannot be caught or ignored */ | |
1562 | perm = PROCESS__SIGKILL; | |
1563 | break; | |
1564 | case SIGSTOP: | |
1565 | /* Cannot be caught or ignored */ | |
1566 | perm = PROCESS__SIGSTOP; | |
1567 | break; | |
1568 | default: | |
1569 | /* All other signals. */ | |
1570 | perm = PROCESS__SIGNAL; | |
1571 | break; | |
1572 | } | |
1573 | ||
1574 | return perm; | |
1575 | } | |
1576 | ||
b68e418c SS |
1577 | #if CAP_LAST_CAP > 63 |
1578 | #error Fix SELinux to handle capabilities > 63. | |
1579 | #endif | |
1580 | ||
1da177e4 | 1581 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1582 | static int cred_has_capability(const struct cred *cred, |
c1a85a00 | 1583 | int cap, unsigned int opts, bool initns) |
1da177e4 | 1584 | { |
2bf49690 | 1585 | struct common_audit_data ad; |
06112163 | 1586 | struct av_decision avd; |
b68e418c | 1587 | u16 sclass; |
3699c53c | 1588 | u32 sid = cred_sid(cred); |
b68e418c | 1589 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1590 | int rc; |
1da177e4 | 1591 | |
50c205f5 | 1592 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1593 | ad.u.cap = cap; |
1594 | ||
b68e418c SS |
1595 | switch (CAP_TO_INDEX(cap)) { |
1596 | case 0: | |
8e4ff6f2 | 1597 | sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; |
b68e418c SS |
1598 | break; |
1599 | case 1: | |
8e4ff6f2 | 1600 | sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; |
b68e418c SS |
1601 | break; |
1602 | default: | |
c103a91e | 1603 | pr_err("SELinux: out of range capability %d\n", cap); |
b68e418c | 1604 | BUG(); |
a35c6c83 | 1605 | return -EINVAL; |
b68e418c | 1606 | } |
06112163 | 1607 | |
6b6bc620 SS |
1608 | rc = avc_has_perm_noaudit(&selinux_state, |
1609 | sid, sid, sclass, av, 0, &avd); | |
c1a85a00 | 1610 | if (!(opts & CAP_OPT_NOAUDIT)) { |
6b6bc620 SS |
1611 | int rc2 = avc_audit(&selinux_state, |
1612 | sid, sid, sclass, av, &avd, rc, &ad, 0); | |
9ade0cf4 EP |
1613 | if (rc2) |
1614 | return rc2; | |
1615 | } | |
06112163 | 1616 | return rc; |
1da177e4 LT |
1617 | } |
1618 | ||
1da177e4 LT |
1619 | /* Check whether a task has a particular permission to an inode. |
1620 | The 'adp' parameter is optional and allows other audit | |
1621 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1622 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1623 | struct inode *inode, |
1624 | u32 perms, | |
19e49834 | 1625 | struct common_audit_data *adp) |
1da177e4 | 1626 | { |
1da177e4 | 1627 | struct inode_security_struct *isec; |
275bb41e | 1628 | u32 sid; |
1da177e4 | 1629 | |
e0e81739 DH |
1630 | validate_creds(cred); |
1631 | ||
828dfe1d | 1632 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1633 | return 0; |
1634 | ||
88e67f3b | 1635 | sid = cred_sid(cred); |
80788c22 | 1636 | isec = selinux_inode(inode); |
1da177e4 | 1637 | |
6b6bc620 SS |
1638 | return avc_has_perm(&selinux_state, |
1639 | sid, isec->sid, isec->sclass, perms, adp); | |
1da177e4 LT |
1640 | } |
1641 | ||
1642 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1643 | the dentry to help the auditing code to more easily generate the | |
1644 | pathname if needed. */ | |
88e67f3b | 1645 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1646 | struct dentry *dentry, |
1647 | u32 av) | |
1648 | { | |
c6f493d6 | 1649 | struct inode *inode = d_backing_inode(dentry); |
2bf49690 | 1650 | struct common_audit_data ad; |
88e67f3b | 1651 | |
50c205f5 | 1652 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1653 | ad.u.dentry = dentry; |
5d226df4 | 1654 | __inode_security_revalidate(inode, dentry, true); |
19e49834 | 1655 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1656 | } |
1657 | ||
1658 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1659 | the path to help the auditing code to more easily generate the | |
1660 | pathname if needed. */ | |
1661 | static inline int path_has_perm(const struct cred *cred, | |
3f7036a0 | 1662 | const struct path *path, |
2875fa00 EP |
1663 | u32 av) |
1664 | { | |
c6f493d6 | 1665 | struct inode *inode = d_backing_inode(path->dentry); |
2875fa00 EP |
1666 | struct common_audit_data ad; |
1667 | ||
50c205f5 | 1668 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1669 | ad.u.path = *path; |
5d226df4 | 1670 | __inode_security_revalidate(inode, path->dentry, true); |
19e49834 | 1671 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1672 | } |
1673 | ||
13f8e981 DH |
1674 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1675 | static inline int file_path_has_perm(const struct cred *cred, | |
1676 | struct file *file, | |
1677 | u32 av) | |
1678 | { | |
1679 | struct common_audit_data ad; | |
1680 | ||
43af5de7 VG |
1681 | ad.type = LSM_AUDIT_DATA_FILE; |
1682 | ad.u.file = file; | |
19e49834 | 1683 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1684 | } |
1685 | ||
f66e448c CF |
1686 | #ifdef CONFIG_BPF_SYSCALL |
1687 | static int bpf_fd_pass(struct file *file, u32 sid); | |
1688 | #endif | |
1689 | ||
1da177e4 LT |
1690 | /* Check whether a task can use an open file descriptor to |
1691 | access an inode in a given way. Check access to the | |
1692 | descriptor itself, and then use dentry_has_perm to | |
1693 | check a particular permission to the file. | |
1694 | Access to the descriptor is implicitly granted if it | |
1695 | has the same SID as the process. If av is zero, then | |
1696 | access to the file is not checked, e.g. for cases | |
1697 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1698 | static int file_has_perm(const struct cred *cred, |
1699 | struct file *file, | |
1700 | u32 av) | |
1da177e4 | 1701 | { |
bb6c6b02 | 1702 | struct file_security_struct *fsec = selinux_file(file); |
496ad9aa | 1703 | struct inode *inode = file_inode(file); |
2bf49690 | 1704 | struct common_audit_data ad; |
88e67f3b | 1705 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1706 | int rc; |
1707 | ||
43af5de7 VG |
1708 | ad.type = LSM_AUDIT_DATA_FILE; |
1709 | ad.u.file = file; | |
1da177e4 | 1710 | |
275bb41e | 1711 | if (sid != fsec->sid) { |
6b6bc620 SS |
1712 | rc = avc_has_perm(&selinux_state, |
1713 | sid, fsec->sid, | |
1da177e4 LT |
1714 | SECCLASS_FD, |
1715 | FD__USE, | |
1716 | &ad); | |
1717 | if (rc) | |
88e67f3b | 1718 | goto out; |
1da177e4 LT |
1719 | } |
1720 | ||
f66e448c CF |
1721 | #ifdef CONFIG_BPF_SYSCALL |
1722 | rc = bpf_fd_pass(file, cred_sid(cred)); | |
1723 | if (rc) | |
1724 | return rc; | |
1725 | #endif | |
1726 | ||
1da177e4 | 1727 | /* av is zero if only checking access to the descriptor. */ |
88e67f3b | 1728 | rc = 0; |
1da177e4 | 1729 | if (av) |
19e49834 | 1730 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1731 | |
88e67f3b DH |
1732 | out: |
1733 | return rc; | |
1da177e4 LT |
1734 | } |
1735 | ||
c3c188b2 DH |
1736 | /* |
1737 | * Determine the label for an inode that might be unioned. | |
1738 | */ | |
c957f6df VG |
1739 | static int |
1740 | selinux_determine_inode_label(const struct task_security_struct *tsec, | |
1741 | struct inode *dir, | |
1742 | const struct qstr *name, u16 tclass, | |
1743 | u32 *_new_isid) | |
c3c188b2 DH |
1744 | { |
1745 | const struct superblock_security_struct *sbsec = dir->i_sb->s_security; | |
c3c188b2 DH |
1746 | |
1747 | if ((sbsec->flags & SE_SBINITIALIZED) && | |
1748 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { | |
1749 | *_new_isid = sbsec->mntpoint_sid; | |
1750 | } else if ((sbsec->flags & SBLABEL_MNT) && | |
1751 | tsec->create_sid) { | |
1752 | *_new_isid = tsec->create_sid; | |
1753 | } else { | |
20cdef8d | 1754 | const struct inode_security_struct *dsec = inode_security(dir); |
aa8e712c SS |
1755 | return security_transition_sid(&selinux_state, tsec->sid, |
1756 | dsec->sid, tclass, | |
c3c188b2 DH |
1757 | name, _new_isid); |
1758 | } | |
1759 | ||
1760 | return 0; | |
1761 | } | |
1762 | ||
1da177e4 LT |
1763 | /* Check whether a task can create a file. */ |
1764 | static int may_create(struct inode *dir, | |
1765 | struct dentry *dentry, | |
1766 | u16 tclass) | |
1767 | { | |
0c6cfa62 | 1768 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
1da177e4 LT |
1769 | struct inode_security_struct *dsec; |
1770 | struct superblock_security_struct *sbsec; | |
275bb41e | 1771 | u32 sid, newsid; |
2bf49690 | 1772 | struct common_audit_data ad; |
1da177e4 LT |
1773 | int rc; |
1774 | ||
83da53c5 | 1775 | dsec = inode_security(dir); |
1da177e4 LT |
1776 | sbsec = dir->i_sb->s_security; |
1777 | ||
275bb41e | 1778 | sid = tsec->sid; |
275bb41e | 1779 | |
50c205f5 | 1780 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1781 | ad.u.dentry = dentry; |
1da177e4 | 1782 | |
6b6bc620 SS |
1783 | rc = avc_has_perm(&selinux_state, |
1784 | sid, dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
1785 | DIR__ADD_NAME | DIR__SEARCH, |
1786 | &ad); | |
1787 | if (rc) | |
1788 | return rc; | |
1789 | ||
210a2928 YG |
1790 | rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, |
1791 | &newsid); | |
c3c188b2 DH |
1792 | if (rc) |
1793 | return rc; | |
1da177e4 | 1794 | |
6b6bc620 SS |
1795 | rc = avc_has_perm(&selinux_state, |
1796 | sid, newsid, tclass, FILE__CREATE, &ad); | |
1da177e4 LT |
1797 | if (rc) |
1798 | return rc; | |
1799 | ||
6b6bc620 SS |
1800 | return avc_has_perm(&selinux_state, |
1801 | newsid, sbsec->sid, | |
1da177e4 LT |
1802 | SECCLASS_FILESYSTEM, |
1803 | FILESYSTEM__ASSOCIATE, &ad); | |
1804 | } | |
1805 | ||
828dfe1d EP |
1806 | #define MAY_LINK 0 |
1807 | #define MAY_UNLINK 1 | |
1808 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1809 | |
1810 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1811 | static int may_link(struct inode *dir, | |
1812 | struct dentry *dentry, | |
1813 | int kind) | |
1814 | ||
1815 | { | |
1da177e4 | 1816 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 1817 | struct common_audit_data ad; |
275bb41e | 1818 | u32 sid = current_sid(); |
1da177e4 LT |
1819 | u32 av; |
1820 | int rc; | |
1821 | ||
83da53c5 AG |
1822 | dsec = inode_security(dir); |
1823 | isec = backing_inode_security(dentry); | |
1da177e4 | 1824 | |
50c205f5 | 1825 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1826 | ad.u.dentry = dentry; |
1da177e4 LT |
1827 | |
1828 | av = DIR__SEARCH; | |
1829 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
6b6bc620 SS |
1830 | rc = avc_has_perm(&selinux_state, |
1831 | sid, dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
1832 | if (rc) |
1833 | return rc; | |
1834 | ||
1835 | switch (kind) { | |
1836 | case MAY_LINK: | |
1837 | av = FILE__LINK; | |
1838 | break; | |
1839 | case MAY_UNLINK: | |
1840 | av = FILE__UNLINK; | |
1841 | break; | |
1842 | case MAY_RMDIR: | |
1843 | av = DIR__RMDIR; | |
1844 | break; | |
1845 | default: | |
c103a91e | 1846 | pr_warn("SELinux: %s: unrecognized kind %d\n", |
744ba35e | 1847 | __func__, kind); |
1da177e4 LT |
1848 | return 0; |
1849 | } | |
1850 | ||
6b6bc620 SS |
1851 | rc = avc_has_perm(&selinux_state, |
1852 | sid, isec->sid, isec->sclass, av, &ad); | |
1da177e4 LT |
1853 | return rc; |
1854 | } | |
1855 | ||
1856 | static inline int may_rename(struct inode *old_dir, | |
1857 | struct dentry *old_dentry, | |
1858 | struct inode *new_dir, | |
1859 | struct dentry *new_dentry) | |
1860 | { | |
1da177e4 | 1861 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 1862 | struct common_audit_data ad; |
275bb41e | 1863 | u32 sid = current_sid(); |
1da177e4 LT |
1864 | u32 av; |
1865 | int old_is_dir, new_is_dir; | |
1866 | int rc; | |
1867 | ||
83da53c5 AG |
1868 | old_dsec = inode_security(old_dir); |
1869 | old_isec = backing_inode_security(old_dentry); | |
e36cb0b8 | 1870 | old_is_dir = d_is_dir(old_dentry); |
83da53c5 | 1871 | new_dsec = inode_security(new_dir); |
1da177e4 | 1872 | |
50c205f5 | 1873 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 1874 | |
a269434d | 1875 | ad.u.dentry = old_dentry; |
6b6bc620 SS |
1876 | rc = avc_has_perm(&selinux_state, |
1877 | sid, old_dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
1878 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
1879 | if (rc) | |
1880 | return rc; | |
6b6bc620 SS |
1881 | rc = avc_has_perm(&selinux_state, |
1882 | sid, old_isec->sid, | |
1da177e4 LT |
1883 | old_isec->sclass, FILE__RENAME, &ad); |
1884 | if (rc) | |
1885 | return rc; | |
1886 | if (old_is_dir && new_dir != old_dir) { | |
6b6bc620 SS |
1887 | rc = avc_has_perm(&selinux_state, |
1888 | sid, old_isec->sid, | |
1da177e4 LT |
1889 | old_isec->sclass, DIR__REPARENT, &ad); |
1890 | if (rc) | |
1891 | return rc; | |
1892 | } | |
1893 | ||
a269434d | 1894 | ad.u.dentry = new_dentry; |
1da177e4 | 1895 | av = DIR__ADD_NAME | DIR__SEARCH; |
2c616d4d | 1896 | if (d_is_positive(new_dentry)) |
1da177e4 | 1897 | av |= DIR__REMOVE_NAME; |
6b6bc620 SS |
1898 | rc = avc_has_perm(&selinux_state, |
1899 | sid, new_dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
1900 | if (rc) |
1901 | return rc; | |
2c616d4d | 1902 | if (d_is_positive(new_dentry)) { |
83da53c5 | 1903 | new_isec = backing_inode_security(new_dentry); |
e36cb0b8 | 1904 | new_is_dir = d_is_dir(new_dentry); |
6b6bc620 SS |
1905 | rc = avc_has_perm(&selinux_state, |
1906 | sid, new_isec->sid, | |
1da177e4 LT |
1907 | new_isec->sclass, |
1908 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1909 | if (rc) | |
1910 | return rc; | |
1911 | } | |
1912 | ||
1913 | return 0; | |
1914 | } | |
1915 | ||
1916 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 1917 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
1918 | struct super_block *sb, |
1919 | u32 perms, | |
2bf49690 | 1920 | struct common_audit_data *ad) |
1da177e4 | 1921 | { |
1da177e4 | 1922 | struct superblock_security_struct *sbsec; |
88e67f3b | 1923 | u32 sid = cred_sid(cred); |
1da177e4 | 1924 | |
1da177e4 | 1925 | sbsec = sb->s_security; |
6b6bc620 SS |
1926 | return avc_has_perm(&selinux_state, |
1927 | sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); | |
1da177e4 LT |
1928 | } |
1929 | ||
1930 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1931 | static inline u32 file_mask_to_av(int mode, int mask) | |
1932 | { | |
1933 | u32 av = 0; | |
1934 | ||
dba19c60 | 1935 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
1936 | if (mask & MAY_EXEC) |
1937 | av |= FILE__EXECUTE; | |
1938 | if (mask & MAY_READ) | |
1939 | av |= FILE__READ; | |
1940 | ||
1941 | if (mask & MAY_APPEND) | |
1942 | av |= FILE__APPEND; | |
1943 | else if (mask & MAY_WRITE) | |
1944 | av |= FILE__WRITE; | |
1945 | ||
1946 | } else { | |
1947 | if (mask & MAY_EXEC) | |
1948 | av |= DIR__SEARCH; | |
1949 | if (mask & MAY_WRITE) | |
1950 | av |= DIR__WRITE; | |
1951 | if (mask & MAY_READ) | |
1952 | av |= DIR__READ; | |
1953 | } | |
1954 | ||
1955 | return av; | |
1956 | } | |
1957 | ||
8b6a5a37 EP |
1958 | /* Convert a Linux file to an access vector. */ |
1959 | static inline u32 file_to_av(struct file *file) | |
1960 | { | |
1961 | u32 av = 0; | |
1962 | ||
1963 | if (file->f_mode & FMODE_READ) | |
1964 | av |= FILE__READ; | |
1965 | if (file->f_mode & FMODE_WRITE) { | |
1966 | if (file->f_flags & O_APPEND) | |
1967 | av |= FILE__APPEND; | |
1968 | else | |
1969 | av |= FILE__WRITE; | |
1970 | } | |
1971 | if (!av) { | |
1972 | /* | |
1973 | * Special file opened with flags 3 for ioctl-only use. | |
1974 | */ | |
1975 | av = FILE__IOCTL; | |
1976 | } | |
1977 | ||
1978 | return av; | |
1979 | } | |
1980 | ||
b0c636b9 | 1981 | /* |
c76a2f9e | 1982 | * Convert a file to an access vector and include the correct |
b0c636b9 EP |
1983 | * open permission. |
1984 | */ | |
8b6a5a37 | 1985 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 1986 | { |
8b6a5a37 | 1987 | u32 av = file_to_av(file); |
ccb54478 | 1988 | struct inode *inode = file_inode(file); |
b0c636b9 | 1989 | |
aa8e712c SS |
1990 | if (selinux_policycap_openperm() && |
1991 | inode->i_sb->s_magic != SOCKFS_MAGIC) | |
49b7b8de EP |
1992 | av |= FILE__OPEN; |
1993 | ||
b0c636b9 EP |
1994 | return av; |
1995 | } | |
1996 | ||
1da177e4 LT |
1997 | /* Hook functions begin here. */ |
1998 | ||
79af7307 SS |
1999 | static int selinux_binder_set_context_mgr(struct task_struct *mgr) |
2000 | { | |
2001 | u32 mysid = current_sid(); | |
2002 | u32 mgrsid = task_sid(mgr); | |
2003 | ||
6b6bc620 SS |
2004 | return avc_has_perm(&selinux_state, |
2005 | mysid, mgrsid, SECCLASS_BINDER, | |
79af7307 SS |
2006 | BINDER__SET_CONTEXT_MGR, NULL); |
2007 | } | |
2008 | ||
2009 | static int selinux_binder_transaction(struct task_struct *from, | |
2010 | struct task_struct *to) | |
2011 | { | |
2012 | u32 mysid = current_sid(); | |
2013 | u32 fromsid = task_sid(from); | |
2014 | u32 tosid = task_sid(to); | |
2015 | int rc; | |
2016 | ||
2017 | if (mysid != fromsid) { | |
6b6bc620 SS |
2018 | rc = avc_has_perm(&selinux_state, |
2019 | mysid, fromsid, SECCLASS_BINDER, | |
79af7307 SS |
2020 | BINDER__IMPERSONATE, NULL); |
2021 | if (rc) | |
2022 | return rc; | |
2023 | } | |
2024 | ||
6b6bc620 SS |
2025 | return avc_has_perm(&selinux_state, |
2026 | fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, | |
79af7307 SS |
2027 | NULL); |
2028 | } | |
2029 | ||
2030 | static int selinux_binder_transfer_binder(struct task_struct *from, | |
2031 | struct task_struct *to) | |
2032 | { | |
2033 | u32 fromsid = task_sid(from); | |
2034 | u32 tosid = task_sid(to); | |
2035 | ||
6b6bc620 SS |
2036 | return avc_has_perm(&selinux_state, |
2037 | fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, | |
79af7307 SS |
2038 | NULL); |
2039 | } | |
2040 | ||
2041 | static int selinux_binder_transfer_file(struct task_struct *from, | |
2042 | struct task_struct *to, | |
2043 | struct file *file) | |
2044 | { | |
2045 | u32 sid = task_sid(to); | |
bb6c6b02 | 2046 | struct file_security_struct *fsec = selinux_file(file); |
83da53c5 | 2047 | struct dentry *dentry = file->f_path.dentry; |
20cdef8d | 2048 | struct inode_security_struct *isec; |
79af7307 SS |
2049 | struct common_audit_data ad; |
2050 | int rc; | |
2051 | ||
2052 | ad.type = LSM_AUDIT_DATA_PATH; | |
2053 | ad.u.path = file->f_path; | |
2054 | ||
2055 | if (sid != fsec->sid) { | |
6b6bc620 SS |
2056 | rc = avc_has_perm(&selinux_state, |
2057 | sid, fsec->sid, | |
79af7307 SS |
2058 | SECCLASS_FD, |
2059 | FD__USE, | |
2060 | &ad); | |
2061 | if (rc) | |
2062 | return rc; | |
2063 | } | |
2064 | ||
f66e448c CF |
2065 | #ifdef CONFIG_BPF_SYSCALL |
2066 | rc = bpf_fd_pass(file, sid); | |
2067 | if (rc) | |
2068 | return rc; | |
2069 | #endif | |
2070 | ||
83da53c5 | 2071 | if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
79af7307 SS |
2072 | return 0; |
2073 | ||
20cdef8d | 2074 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
2075 | return avc_has_perm(&selinux_state, |
2076 | sid, isec->sid, isec->sclass, file_to_av(file), | |
79af7307 SS |
2077 | &ad); |
2078 | } | |
2079 | ||
9e48858f | 2080 | static int selinux_ptrace_access_check(struct task_struct *child, |
5cd9c58f | 2081 | unsigned int mode) |
1da177e4 | 2082 | { |
be0554c9 SS |
2083 | u32 sid = current_sid(); |
2084 | u32 csid = task_sid(child); | |
2085 | ||
2086 | if (mode & PTRACE_MODE_READ) | |
6b6bc620 SS |
2087 | return avc_has_perm(&selinux_state, |
2088 | sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 | 2089 | |
6b6bc620 SS |
2090 | return avc_has_perm(&selinux_state, |
2091 | sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); | |
5cd9c58f DH |
2092 | } |
2093 | ||
2094 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
2095 | { | |
6b6bc620 SS |
2096 | return avc_has_perm(&selinux_state, |
2097 | task_sid(parent), current_sid(), SECCLASS_PROCESS, | |
be0554c9 | 2098 | PROCESS__PTRACE, NULL); |
1da177e4 LT |
2099 | } |
2100 | ||
2101 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 2102 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 | 2103 | { |
6b6bc620 SS |
2104 | return avc_has_perm(&selinux_state, |
2105 | current_sid(), task_sid(target), SECCLASS_PROCESS, | |
be0554c9 | 2106 | PROCESS__GETCAP, NULL); |
1da177e4 LT |
2107 | } |
2108 | ||
d84f4f99 DH |
2109 | static int selinux_capset(struct cred *new, const struct cred *old, |
2110 | const kernel_cap_t *effective, | |
2111 | const kernel_cap_t *inheritable, | |
2112 | const kernel_cap_t *permitted) | |
1da177e4 | 2113 | { |
6b6bc620 SS |
2114 | return avc_has_perm(&selinux_state, |
2115 | cred_sid(old), cred_sid(new), SECCLASS_PROCESS, | |
be0554c9 | 2116 | PROCESS__SETCAP, NULL); |
1da177e4 LT |
2117 | } |
2118 | ||
5626d3e8 JM |
2119 | /* |
2120 | * (This comment used to live with the selinux_task_setuid hook, | |
2121 | * which was removed). | |
2122 | * | |
2123 | * Since setuid only affects the current process, and since the SELinux | |
2124 | * controls are not based on the Linux identity attributes, SELinux does not | |
2125 | * need to control this operation. However, SELinux does control the use of | |
2126 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
2127 | */ | |
2128 | ||
6a9de491 | 2129 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
c1a85a00 | 2130 | int cap, unsigned int opts) |
1da177e4 | 2131 | { |
c1a85a00 | 2132 | return cred_has_capability(cred, cap, opts, ns == &init_user_ns); |
1da177e4 LT |
2133 | } |
2134 | ||
1da177e4 LT |
2135 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
2136 | { | |
88e67f3b | 2137 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2138 | int rc = 0; |
2139 | ||
2140 | if (!sb) | |
2141 | return 0; | |
2142 | ||
2143 | switch (cmds) { | |
828dfe1d EP |
2144 | case Q_SYNC: |
2145 | case Q_QUOTAON: | |
2146 | case Q_QUOTAOFF: | |
2147 | case Q_SETINFO: | |
2148 | case Q_SETQUOTA: | |
e4cfa05e RH |
2149 | case Q_XQUOTAOFF: |
2150 | case Q_XQUOTAON: | |
2151 | case Q_XSETQLIM: | |
88e67f3b | 2152 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
2153 | break; |
2154 | case Q_GETFMT: | |
2155 | case Q_GETINFO: | |
2156 | case Q_GETQUOTA: | |
e4cfa05e RH |
2157 | case Q_XGETQUOTA: |
2158 | case Q_XGETQSTAT: | |
2159 | case Q_XGETQSTATV: | |
2160 | case Q_XGETNEXTQUOTA: | |
88e67f3b | 2161 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
2162 | break; |
2163 | default: | |
2164 | rc = 0; /* let the kernel handle invalid cmds */ | |
2165 | break; | |
1da177e4 LT |
2166 | } |
2167 | return rc; | |
2168 | } | |
2169 | ||
2170 | static int selinux_quota_on(struct dentry *dentry) | |
2171 | { | |
88e67f3b DH |
2172 | const struct cred *cred = current_cred(); |
2173 | ||
2875fa00 | 2174 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
2175 | } |
2176 | ||
12b3052c | 2177 | static int selinux_syslog(int type) |
1da177e4 | 2178 | { |
1da177e4 | 2179 | switch (type) { |
d78ca3cd KC |
2180 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2181 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
6b6bc620 SS |
2182 | return avc_has_perm(&selinux_state, |
2183 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2184 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); |
d78ca3cd KC |
2185 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2186 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2187 | /* Set level of messages printed to console */ | |
2188 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
6b6bc620 SS |
2189 | return avc_has_perm(&selinux_state, |
2190 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 SS |
2191 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, |
2192 | NULL); | |
1da177e4 | 2193 | } |
be0554c9 | 2194 | /* All other syslog types */ |
6b6bc620 SS |
2195 | return avc_has_perm(&selinux_state, |
2196 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2197 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); |
1da177e4 LT |
2198 | } |
2199 | ||
2200 | /* | |
2201 | * Check that a process has enough memory to allocate a new virtual | |
2202 | * mapping. 0 means there is enough memory for the allocation to | |
2203 | * succeed and -ENOMEM implies there is not. | |
2204 | * | |
1da177e4 LT |
2205 | * Do not audit the selinux permission check, as this is applied to all |
2206 | * processes that allocate mappings. | |
2207 | */ | |
34b4e4aa | 2208 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2209 | { |
2210 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2211 | |
b1d9e6b0 | 2212 | rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, |
c1a85a00 | 2213 | CAP_OPT_NOAUDIT, true); |
1da177e4 LT |
2214 | if (rc == 0) |
2215 | cap_sys_admin = 1; | |
2216 | ||
b1d9e6b0 | 2217 | return cap_sys_admin; |
1da177e4 LT |
2218 | } |
2219 | ||
2220 | /* binprm security operations */ | |
2221 | ||
be0554c9 | 2222 | static u32 ptrace_parent_sid(void) |
0c6181cb PM |
2223 | { |
2224 | u32 sid = 0; | |
2225 | struct task_struct *tracer; | |
2226 | ||
2227 | rcu_read_lock(); | |
be0554c9 | 2228 | tracer = ptrace_parent(current); |
0c6181cb PM |
2229 | if (tracer) |
2230 | sid = task_sid(tracer); | |
2231 | rcu_read_unlock(); | |
2232 | ||
2233 | return sid; | |
2234 | } | |
2235 | ||
7b0d0b40 SS |
2236 | static int check_nnp_nosuid(const struct linux_binprm *bprm, |
2237 | const struct task_security_struct *old_tsec, | |
2238 | const struct task_security_struct *new_tsec) | |
2239 | { | |
2240 | int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); | |
380cf5ba | 2241 | int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); |
7b0d0b40 | 2242 | int rc; |
af63f419 | 2243 | u32 av; |
7b0d0b40 SS |
2244 | |
2245 | if (!nnp && !nosuid) | |
2246 | return 0; /* neither NNP nor nosuid */ | |
2247 | ||
2248 | if (new_tsec->sid == old_tsec->sid) | |
2249 | return 0; /* No change in credentials */ | |
2250 | ||
2251 | /* | |
af63f419 SS |
2252 | * If the policy enables the nnp_nosuid_transition policy capability, |
2253 | * then we permit transitions under NNP or nosuid if the | |
2254 | * policy allows the corresponding permission between | |
2255 | * the old and new contexts. | |
7b0d0b40 | 2256 | */ |
aa8e712c | 2257 | if (selinux_policycap_nnp_nosuid_transition()) { |
af63f419 | 2258 | av = 0; |
7b0d0b40 | 2259 | if (nnp) |
af63f419 SS |
2260 | av |= PROCESS2__NNP_TRANSITION; |
2261 | if (nosuid) | |
2262 | av |= PROCESS2__NOSUID_TRANSITION; | |
6b6bc620 SS |
2263 | rc = avc_has_perm(&selinux_state, |
2264 | old_tsec->sid, new_tsec->sid, | |
af63f419 SS |
2265 | SECCLASS_PROCESS2, av, NULL); |
2266 | if (!rc) | |
2267 | return 0; | |
7b0d0b40 | 2268 | } |
af63f419 SS |
2269 | |
2270 | /* | |
2271 | * We also permit NNP or nosuid transitions to bounded SIDs, | |
2272 | * i.e. SIDs that are guaranteed to only be allowed a subset | |
2273 | * of the permissions of the current SID. | |
2274 | */ | |
aa8e712c SS |
2275 | rc = security_bounded_transition(&selinux_state, old_tsec->sid, |
2276 | new_tsec->sid); | |
af63f419 SS |
2277 | if (!rc) |
2278 | return 0; | |
2279 | ||
2280 | /* | |
2281 | * On failure, preserve the errno values for NNP vs nosuid. | |
2282 | * NNP: Operation not permitted for caller. | |
2283 | * nosuid: Permission denied to file. | |
2284 | */ | |
2285 | if (nnp) | |
2286 | return -EPERM; | |
2287 | return -EACCES; | |
7b0d0b40 SS |
2288 | } |
2289 | ||
b8bff599 | 2290 | static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) |
1da177e4 | 2291 | { |
a6f76f23 DH |
2292 | const struct task_security_struct *old_tsec; |
2293 | struct task_security_struct *new_tsec; | |
1da177e4 | 2294 | struct inode_security_struct *isec; |
2bf49690 | 2295 | struct common_audit_data ad; |
496ad9aa | 2296 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2297 | int rc; |
2298 | ||
a6f76f23 DH |
2299 | /* SELinux context only depends on initial program or script and not |
2300 | * the script interpreter */ | |
1da177e4 | 2301 | |
0c6cfa62 CS |
2302 | old_tsec = selinux_cred(current_cred()); |
2303 | new_tsec = selinux_cred(bprm->cred); | |
83da53c5 | 2304 | isec = inode_security(inode); |
1da177e4 LT |
2305 | |
2306 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2307 | new_tsec->sid = old_tsec->sid; |
2308 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2309 | |
28eba5bf | 2310 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2311 | new_tsec->create_sid = 0; |
2312 | new_tsec->keycreate_sid = 0; | |
2313 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2314 | |
a6f76f23 DH |
2315 | if (old_tsec->exec_sid) { |
2316 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2317 | /* Reset exec SID on execve. */ |
a6f76f23 | 2318 | new_tsec->exec_sid = 0; |
259e5e6c | 2319 | |
7b0d0b40 SS |
2320 | /* Fail on NNP or nosuid if not an allowed transition. */ |
2321 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2322 | if (rc) | |
2323 | return rc; | |
1da177e4 LT |
2324 | } else { |
2325 | /* Check for a default transition on this program. */ | |
aa8e712c SS |
2326 | rc = security_transition_sid(&selinux_state, old_tsec->sid, |
2327 | isec->sid, SECCLASS_PROCESS, NULL, | |
652bb9b0 | 2328 | &new_tsec->sid); |
1da177e4 LT |
2329 | if (rc) |
2330 | return rc; | |
7b0d0b40 SS |
2331 | |
2332 | /* | |
2333 | * Fallback to old SID on NNP or nosuid if not an allowed | |
2334 | * transition. | |
2335 | */ | |
2336 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2337 | if (rc) | |
2338 | new_tsec->sid = old_tsec->sid; | |
1da177e4 LT |
2339 | } |
2340 | ||
43af5de7 VG |
2341 | ad.type = LSM_AUDIT_DATA_FILE; |
2342 | ad.u.file = bprm->file; | |
1da177e4 | 2343 | |
a6f76f23 | 2344 | if (new_tsec->sid == old_tsec->sid) { |
6b6bc620 SS |
2345 | rc = avc_has_perm(&selinux_state, |
2346 | old_tsec->sid, isec->sid, | |
1da177e4 LT |
2347 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2348 | if (rc) | |
2349 | return rc; | |
2350 | } else { | |
2351 | /* Check permissions for the transition. */ | |
6b6bc620 SS |
2352 | rc = avc_has_perm(&selinux_state, |
2353 | old_tsec->sid, new_tsec->sid, | |
1da177e4 LT |
2354 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2355 | if (rc) | |
2356 | return rc; | |
2357 | ||
6b6bc620 SS |
2358 | rc = avc_has_perm(&selinux_state, |
2359 | new_tsec->sid, isec->sid, | |
1da177e4 LT |
2360 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2361 | if (rc) | |
2362 | return rc; | |
2363 | ||
a6f76f23 DH |
2364 | /* Check for shared state */ |
2365 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
6b6bc620 SS |
2366 | rc = avc_has_perm(&selinux_state, |
2367 | old_tsec->sid, new_tsec->sid, | |
a6f76f23 DH |
2368 | SECCLASS_PROCESS, PROCESS__SHARE, |
2369 | NULL); | |
2370 | if (rc) | |
2371 | return -EPERM; | |
2372 | } | |
2373 | ||
2374 | /* Make sure that anyone attempting to ptrace over a task that | |
2375 | * changes its SID has the appropriate permit */ | |
9227dd2a | 2376 | if (bprm->unsafe & LSM_UNSAFE_PTRACE) { |
be0554c9 | 2377 | u32 ptsid = ptrace_parent_sid(); |
a6f76f23 | 2378 | if (ptsid != 0) { |
6b6bc620 SS |
2379 | rc = avc_has_perm(&selinux_state, |
2380 | ptsid, new_tsec->sid, | |
a6f76f23 DH |
2381 | SECCLASS_PROCESS, |
2382 | PROCESS__PTRACE, NULL); | |
2383 | if (rc) | |
2384 | return -EPERM; | |
2385 | } | |
2386 | } | |
1da177e4 | 2387 | |
a6f76f23 DH |
2388 | /* Clear any possibly unsafe personality bits on exec: */ |
2389 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
275bb41e | 2390 | |
1da177e4 LT |
2391 | /* Enable secure mode for SIDs transitions unless |
2392 | the noatsecure permission is granted between | |
2393 | the two SIDs, i.e. ahp returns 0. */ | |
6b6bc620 SS |
2394 | rc = avc_has_perm(&selinux_state, |
2395 | old_tsec->sid, new_tsec->sid, | |
62874c3a KC |
2396 | SECCLASS_PROCESS, PROCESS__NOATSECURE, |
2397 | NULL); | |
2398 | bprm->secureexec |= !!rc; | |
1da177e4 LT |
2399 | } |
2400 | ||
62874c3a | 2401 | return 0; |
1da177e4 LT |
2402 | } |
2403 | ||
c3c073f8 AV |
2404 | static int match_file(const void *p, struct file *file, unsigned fd) |
2405 | { | |
2406 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2407 | } | |
2408 | ||
1da177e4 | 2409 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2410 | static inline void flush_unauthorized_files(const struct cred *cred, |
2411 | struct files_struct *files) | |
1da177e4 | 2412 | { |
1da177e4 | 2413 | struct file *file, *devnull = NULL; |
b20c8122 | 2414 | struct tty_struct *tty; |
24ec839c | 2415 | int drop_tty = 0; |
c3c073f8 | 2416 | unsigned n; |
1da177e4 | 2417 | |
24ec839c | 2418 | tty = get_current_tty(); |
1da177e4 | 2419 | if (tty) { |
4a510969 | 2420 | spin_lock(&tty->files_lock); |
37dd0bd0 | 2421 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2422 | struct tty_file_private *file_priv; |
37dd0bd0 | 2423 | |
1da177e4 | 2424 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2425 | Use file_path_has_perm on the tty path directly |
2426 | rather than using file_has_perm, as this particular | |
2427 | open file may belong to another process and we are | |
2428 | only interested in the inode-based check here. */ | |
d996b62a NP |
2429 | file_priv = list_first_entry(&tty->tty_files, |
2430 | struct tty_file_private, list); | |
2431 | file = file_priv->file; | |
13f8e981 | 2432 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2433 | drop_tty = 1; |
1da177e4 | 2434 | } |
4a510969 | 2435 | spin_unlock(&tty->files_lock); |
452a00d2 | 2436 | tty_kref_put(tty); |
1da177e4 | 2437 | } |
98a27ba4 EB |
2438 | /* Reset controlling tty. */ |
2439 | if (drop_tty) | |
2440 | no_tty(); | |
1da177e4 LT |
2441 | |
2442 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2443 | n = iterate_fd(files, 0, match_file, cred); |
2444 | if (!n) /* none found? */ | |
2445 | return; | |
1da177e4 | 2446 | |
c3c073f8 | 2447 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2448 | if (IS_ERR(devnull)) |
2449 | devnull = NULL; | |
2450 | /* replace all the matching ones with this */ | |
2451 | do { | |
2452 | replace_fd(n - 1, devnull, 0); | |
2453 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2454 | if (devnull) | |
c3c073f8 | 2455 | fput(devnull); |
1da177e4 LT |
2456 | } |
2457 | ||
a6f76f23 DH |
2458 | /* |
2459 | * Prepare a process for imminent new credential changes due to exec | |
2460 | */ | |
2461 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2462 | { |
a6f76f23 DH |
2463 | struct task_security_struct *new_tsec; |
2464 | struct rlimit *rlim, *initrlim; | |
2465 | int rc, i; | |
d84f4f99 | 2466 | |
0c6cfa62 | 2467 | new_tsec = selinux_cred(bprm->cred); |
a6f76f23 DH |
2468 | if (new_tsec->sid == new_tsec->osid) |
2469 | return; | |
1da177e4 | 2470 | |
a6f76f23 DH |
2471 | /* Close files for which the new task SID is not authorized. */ |
2472 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2473 | |
a6f76f23 DH |
2474 | /* Always clear parent death signal on SID transitions. */ |
2475 | current->pdeath_signal = 0; | |
0356357c | 2476 | |
a6f76f23 DH |
2477 | /* Check whether the new SID can inherit resource limits from the old |
2478 | * SID. If not, reset all soft limits to the lower of the current | |
2479 | * task's hard limit and the init task's soft limit. | |
2480 | * | |
2481 | * Note that the setting of hard limits (even to lower them) can be | |
2482 | * controlled by the setrlimit check. The inclusion of the init task's | |
2483 | * soft limit into the computation is to avoid resetting soft limits | |
2484 | * higher than the default soft limit for cases where the default is | |
2485 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2486 | */ | |
6b6bc620 SS |
2487 | rc = avc_has_perm(&selinux_state, |
2488 | new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
a6f76f23 DH |
2489 | PROCESS__RLIMITINH, NULL); |
2490 | if (rc) { | |
eb2d55a3 ON |
2491 | /* protect against do_prlimit() */ |
2492 | task_lock(current); | |
a6f76f23 DH |
2493 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2494 | rlim = current->signal->rlim + i; | |
2495 | initrlim = init_task.signal->rlim + i; | |
2496 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2497 | } |
eb2d55a3 | 2498 | task_unlock(current); |
baa73d9e NP |
2499 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) |
2500 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2501 | } |
2502 | } | |
2503 | ||
2504 | /* | |
a6f76f23 DH |
2505 | * Clean up the process immediately after the installation of new credentials |
2506 | * due to exec | |
1da177e4 | 2507 | */ |
a6f76f23 | 2508 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2509 | { |
0c6cfa62 | 2510 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
a6f76f23 | 2511 | u32 osid, sid; |
ddbc7d06 | 2512 | int rc; |
1da177e4 | 2513 | |
a6f76f23 DH |
2514 | osid = tsec->osid; |
2515 | sid = tsec->sid; | |
2516 | ||
2517 | if (sid == osid) | |
1da177e4 LT |
2518 | return; |
2519 | ||
a6f76f23 DH |
2520 | /* Check whether the new SID can inherit signal state from the old SID. |
2521 | * If not, clear itimers to avoid subsequent signal generation and | |
2522 | * flush and unblock signals. | |
2523 | * | |
2524 | * This must occur _after_ the task SID has been updated so that any | |
2525 | * kill done after the flush will be checked against the new SID. | |
2526 | */ | |
6b6bc620 SS |
2527 | rc = avc_has_perm(&selinux_state, |
2528 | osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 | 2529 | if (rc) { |
ddbc7d06 AB |
2530 | clear_itimer(); |
2531 | ||
1da177e4 | 2532 | spin_lock_irq(¤t->sighand->siglock); |
9e7c8f8c ON |
2533 | if (!fatal_signal_pending(current)) { |
2534 | flush_sigqueue(¤t->pending); | |
2535 | flush_sigqueue(¤t->signal->shared_pending); | |
3bcac026 DH |
2536 | flush_signal_handlers(current, 1); |
2537 | sigemptyset(¤t->blocked); | |
9e7c8f8c | 2538 | recalc_sigpending(); |
3bcac026 | 2539 | } |
1da177e4 LT |
2540 | spin_unlock_irq(¤t->sighand->siglock); |
2541 | } | |
2542 | ||
a6f76f23 DH |
2543 | /* Wake up the parent if it is waiting so that it can recheck |
2544 | * wait permission to the new task SID. */ | |
ecd6de3c | 2545 | read_lock(&tasklist_lock); |
0b7570e7 | 2546 | __wake_up_parent(current, current->real_parent); |
ecd6de3c | 2547 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2548 | } |
2549 | ||
2550 | /* superblock security operations */ | |
2551 | ||
2552 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2553 | { | |
cb89e246 PM |
2554 | struct superblock_security_struct *sbsec; |
2555 | ||
2556 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); | |
2557 | if (!sbsec) | |
2558 | return -ENOMEM; | |
2559 | ||
2560 | mutex_init(&sbsec->lock); | |
2561 | INIT_LIST_HEAD(&sbsec->isec_head); | |
2562 | spin_lock_init(&sbsec->isec_lock); | |
2563 | sbsec->sb = sb; | |
2564 | sbsec->sid = SECINITSID_UNLABELED; | |
2565 | sbsec->def_sid = SECINITSID_FILE; | |
2566 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; | |
2567 | sb->s_security = sbsec; | |
2568 | ||
2569 | return 0; | |
1da177e4 LT |
2570 | } |
2571 | ||
2572 | static void selinux_sb_free_security(struct super_block *sb) | |
2573 | { | |
2574 | superblock_free_security(sb); | |
2575 | } | |
2576 | ||
99dbbb59 | 2577 | static inline int opt_len(const char *s) |
1da177e4 | 2578 | { |
99dbbb59 AV |
2579 | bool open_quote = false; |
2580 | int len; | |
2581 | char c; | |
1da177e4 | 2582 | |
99dbbb59 AV |
2583 | for (len = 0; (c = s[len]) != '\0'; len++) { |
2584 | if (c == '"') | |
2585 | open_quote = !open_quote; | |
2586 | if (c == ',' && !open_quote) | |
2587 | break; | |
3528a953 | 2588 | } |
99dbbb59 | 2589 | return len; |
3528a953 CO |
2590 | } |
2591 | ||
99dbbb59 | 2592 | static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) |
1da177e4 | 2593 | { |
99dbbb59 AV |
2594 | char *from = options; |
2595 | char *to = options; | |
2596 | bool first = true; | |
fec63753 | 2597 | int rc; |
1da177e4 | 2598 | |
99dbbb59 AV |
2599 | while (1) { |
2600 | int len = opt_len(from); | |
fec63753 | 2601 | int token; |
99dbbb59 | 2602 | char *arg = NULL; |
1da177e4 | 2603 | |
99dbbb59 | 2604 | token = match_opt_prefix(from, len, &arg); |
1da177e4 | 2605 | |
99dbbb59 AV |
2606 | if (token != Opt_error) { |
2607 | char *p, *q; | |
1da177e4 | 2608 | |
99dbbb59 AV |
2609 | /* strip quotes */ |
2610 | if (arg) { | |
2611 | for (p = q = arg; p < from + len; p++) { | |
2612 | char c = *p; | |
2613 | if (c != '"') | |
2614 | *q++ = c; | |
2615 | } | |
2616 | arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); | |
fec63753 GZ |
2617 | if (!arg) { |
2618 | rc = -ENOMEM; | |
2619 | goto free_opt; | |
2620 | } | |
99dbbb59 AV |
2621 | } |
2622 | rc = selinux_add_opt(token, arg, mnt_opts); | |
2623 | if (unlikely(rc)) { | |
2624 | kfree(arg); | |
fec63753 | 2625 | goto free_opt; |
99dbbb59 AV |
2626 | } |
2627 | } else { | |
2628 | if (!first) { // copy with preceding comma | |
2629 | from--; | |
2630 | len++; | |
2631 | } | |
2632 | if (to != from) | |
2633 | memmove(to, from, len); | |
2634 | to += len; | |
2635 | first = false; | |
1da177e4 | 2636 | } |
99dbbb59 AV |
2637 | if (!from[len]) |
2638 | break; | |
2639 | from += len + 1; | |
2640 | } | |
2641 | *to = '\0'; | |
2642 | return 0; | |
fec63753 GZ |
2643 | |
2644 | free_opt: | |
2645 | if (*mnt_opts) { | |
2646 | selinux_free_mnt_opts(*mnt_opts); | |
2647 | *mnt_opts = NULL; | |
2648 | } | |
2649 | return rc; | |
1da177e4 LT |
2650 | } |
2651 | ||
204cc0cc | 2652 | static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) |
026eb167 | 2653 | { |
bd323655 | 2654 | struct selinux_mnt_opts *opts = mnt_opts; |
026eb167 | 2655 | struct superblock_security_struct *sbsec = sb->s_security; |
bd323655 AV |
2656 | u32 sid; |
2657 | int rc; | |
026eb167 EP |
2658 | |
2659 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2660 | return 0; | |
2661 | ||
204cc0cc | 2662 | if (!opts) |
026eb167 EP |
2663 | return 0; |
2664 | ||
bd323655 AV |
2665 | if (opts->fscontext) { |
2666 | rc = parse_sid(sb, opts->fscontext, &sid); | |
2667 | if (rc) | |
c039bc3c | 2668 | return rc; |
bd323655 AV |
2669 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) |
2670 | goto out_bad_option; | |
026eb167 | 2671 | } |
bd323655 AV |
2672 | if (opts->context) { |
2673 | rc = parse_sid(sb, opts->context, &sid); | |
2674 | if (rc) | |
2675 | return rc; | |
2676 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2677 | goto out_bad_option; | |
2678 | } | |
2679 | if (opts->rootcontext) { | |
2680 | struct inode_security_struct *root_isec; | |
2681 | root_isec = backing_inode_security(sb->s_root); | |
2682 | rc = parse_sid(sb, opts->rootcontext, &sid); | |
2683 | if (rc) | |
2684 | return rc; | |
2685 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2686 | goto out_bad_option; | |
2687 | } | |
2688 | if (opts->defcontext) { | |
2689 | rc = parse_sid(sb, opts->defcontext, &sid); | |
2690 | if (rc) | |
2691 | return rc; | |
2692 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2693 | goto out_bad_option; | |
026eb167 | 2694 | } |
c039bc3c | 2695 | return 0; |
026eb167 | 2696 | |
026eb167 | 2697 | out_bad_option: |
c103a91e | 2698 | pr_warn("SELinux: unable to change security options " |
29b1deb2 LT |
2699 | "during remount (dev %s, type=%s)\n", sb->s_id, |
2700 | sb->s_type->name); | |
c039bc3c | 2701 | return -EINVAL; |
026eb167 EP |
2702 | } |
2703 | ||
a10d7c22 | 2704 | static int selinux_sb_kern_mount(struct super_block *sb) |
1da177e4 | 2705 | { |
88e67f3b | 2706 | const struct cred *cred = current_cred(); |
2bf49690 | 2707 | struct common_audit_data ad; |
74192246 | 2708 | |
50c205f5 | 2709 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2710 | ad.u.dentry = sb->s_root; |
88e67f3b | 2711 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2712 | } |
2713 | ||
726c3342 | 2714 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2715 | { |
88e67f3b | 2716 | const struct cred *cred = current_cred(); |
2bf49690 | 2717 | struct common_audit_data ad; |
1da177e4 | 2718 | |
50c205f5 | 2719 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2720 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2721 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2722 | } |
2723 | ||
808d4e3c | 2724 | static int selinux_mount(const char *dev_name, |
8a04c43b | 2725 | const struct path *path, |
808d4e3c | 2726 | const char *type, |
828dfe1d EP |
2727 | unsigned long flags, |
2728 | void *data) | |
1da177e4 | 2729 | { |
88e67f3b | 2730 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2731 | |
2732 | if (flags & MS_REMOUNT) | |
d8c9584e | 2733 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2734 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2735 | else |
2875fa00 | 2736 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2737 | } |
2738 | ||
98aa0034 SS |
2739 | static int selinux_move_mount(const struct path *from_path, |
2740 | const struct path *to_path) | |
2741 | { | |
2742 | const struct cred *cred = current_cred(); | |
2743 | ||
2744 | return path_has_perm(cred, to_path, FILE__MOUNTON); | |
2745 | } | |
2746 | ||
1da177e4 LT |
2747 | static int selinux_umount(struct vfsmount *mnt, int flags) |
2748 | { | |
88e67f3b | 2749 | const struct cred *cred = current_cred(); |
1da177e4 | 2750 | |
88e67f3b | 2751 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2752 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2753 | } |
2754 | ||
0b52075e AV |
2755 | static int selinux_fs_context_dup(struct fs_context *fc, |
2756 | struct fs_context *src_fc) | |
2757 | { | |
2758 | const struct selinux_mnt_opts *src = src_fc->security; | |
2759 | struct selinux_mnt_opts *opts; | |
2760 | ||
2761 | if (!src) | |
2762 | return 0; | |
2763 | ||
2764 | fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); | |
2765 | if (!fc->security) | |
2766 | return -ENOMEM; | |
2767 | ||
2768 | opts = fc->security; | |
2769 | ||
2770 | if (src->fscontext) { | |
2771 | opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL); | |
2772 | if (!opts->fscontext) | |
2773 | return -ENOMEM; | |
2774 | } | |
2775 | if (src->context) { | |
2776 | opts->context = kstrdup(src->context, GFP_KERNEL); | |
2777 | if (!opts->context) | |
2778 | return -ENOMEM; | |
2779 | } | |
2780 | if (src->rootcontext) { | |
2781 | opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL); | |
2782 | if (!opts->rootcontext) | |
2783 | return -ENOMEM; | |
2784 | } | |
2785 | if (src->defcontext) { | |
2786 | opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL); | |
2787 | if (!opts->defcontext) | |
2788 | return -ENOMEM; | |
2789 | } | |
2790 | return 0; | |
2791 | } | |
2792 | ||
d7167b14 | 2793 | static const struct fs_parameter_spec selinux_fs_parameters[] = { |
442155c1 DH |
2794 | fsparam_string(CONTEXT_STR, Opt_context), |
2795 | fsparam_string(DEFCONTEXT_STR, Opt_defcontext), | |
2796 | fsparam_string(FSCONTEXT_STR, Opt_fscontext), | |
2797 | fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), | |
2798 | fsparam_flag (SECLABEL_STR, Opt_seclabel), | |
2799 | {} | |
2800 | }; | |
2801 | ||
442155c1 DH |
2802 | static int selinux_fs_context_parse_param(struct fs_context *fc, |
2803 | struct fs_parameter *param) | |
2804 | { | |
2805 | struct fs_parse_result result; | |
2806 | int opt, rc; | |
2807 | ||
d7167b14 | 2808 | opt = fs_parse(fc, selinux_fs_parameters, param, &result); |
442155c1 DH |
2809 | if (opt < 0) |
2810 | return opt; | |
2811 | ||
2812 | rc = selinux_add_opt(opt, param->string, &fc->security); | |
2813 | if (!rc) { | |
2814 | param->string = NULL; | |
2815 | rc = 1; | |
2816 | } | |
2817 | return rc; | |
2818 | } | |
2819 | ||
1da177e4 LT |
2820 | /* inode security operations */ |
2821 | ||
2822 | static int selinux_inode_alloc_security(struct inode *inode) | |
2823 | { | |
cb89e246 PM |
2824 | struct inode_security_struct *isec = selinux_inode(inode); |
2825 | u32 sid = current_sid(); | |
2826 | ||
2827 | spin_lock_init(&isec->lock); | |
2828 | INIT_LIST_HEAD(&isec->list); | |
2829 | isec->inode = inode; | |
2830 | isec->sid = SECINITSID_UNLABELED; | |
2831 | isec->sclass = SECCLASS_FILE; | |
2832 | isec->task_sid = sid; | |
2833 | isec->initialized = LABEL_INVALID; | |
2834 | ||
2835 | return 0; | |
1da177e4 LT |
2836 | } |
2837 | ||
2838 | static void selinux_inode_free_security(struct inode *inode) | |
2839 | { | |
2840 | inode_free_security(inode); | |
2841 | } | |
2842 | ||
d47be3df | 2843 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
4f3ccd76 | 2844 | const struct qstr *name, void **ctx, |
d47be3df DQ |
2845 | u32 *ctxlen) |
2846 | { | |
d47be3df DQ |
2847 | u32 newsid; |
2848 | int rc; | |
2849 | ||
0c6cfa62 | 2850 | rc = selinux_determine_inode_label(selinux_cred(current_cred()), |
c957f6df | 2851 | d_inode(dentry->d_parent), name, |
c3c188b2 DH |
2852 | inode_mode_to_security_class(mode), |
2853 | &newsid); | |
2854 | if (rc) | |
2855 | return rc; | |
d47be3df | 2856 | |
aa8e712c SS |
2857 | return security_sid_to_context(&selinux_state, newsid, (char **)ctx, |
2858 | ctxlen); | |
d47be3df DQ |
2859 | } |
2860 | ||
a518b0a5 VG |
2861 | static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, |
2862 | struct qstr *name, | |
2863 | const struct cred *old, | |
2864 | struct cred *new) | |
2865 | { | |
2866 | u32 newsid; | |
2867 | int rc; | |
2868 | struct task_security_struct *tsec; | |
2869 | ||
0c6cfa62 | 2870 | rc = selinux_determine_inode_label(selinux_cred(old), |
a518b0a5 VG |
2871 | d_inode(dentry->d_parent), name, |
2872 | inode_mode_to_security_class(mode), | |
2873 | &newsid); | |
2874 | if (rc) | |
2875 | return rc; | |
2876 | ||
0c6cfa62 | 2877 | tsec = selinux_cred(new); |
a518b0a5 VG |
2878 | tsec->create_sid = newsid; |
2879 | return 0; | |
2880 | } | |
2881 | ||
5e41ff9e | 2882 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
2883 | const struct qstr *qstr, |
2884 | const char **name, | |
2a7dba39 | 2885 | void **value, size_t *len) |
5e41ff9e | 2886 | { |
0c6cfa62 | 2887 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
5e41ff9e | 2888 | struct superblock_security_struct *sbsec; |
c0d4f464 | 2889 | u32 newsid, clen; |
5e41ff9e | 2890 | int rc; |
9548906b | 2891 | char *context; |
5e41ff9e | 2892 | |
5e41ff9e | 2893 | sbsec = dir->i_sb->s_security; |
5e41ff9e | 2894 | |
275bb41e DH |
2895 | newsid = tsec->create_sid; |
2896 | ||
210a2928 | 2897 | rc = selinux_determine_inode_label(tsec, dir, qstr, |
c3c188b2 DH |
2898 | inode_mode_to_security_class(inode->i_mode), |
2899 | &newsid); | |
2900 | if (rc) | |
2901 | return rc; | |
5e41ff9e | 2902 | |
296fddf7 | 2903 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 2904 | if (sbsec->flags & SE_SBINITIALIZED) { |
80788c22 | 2905 | struct inode_security_struct *isec = selinux_inode(inode); |
296fddf7 EP |
2906 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
2907 | isec->sid = newsid; | |
6f3be9f5 | 2908 | isec->initialized = LABEL_INITIALIZED; |
296fddf7 | 2909 | } |
5e41ff9e | 2910 | |
65cddd50 OM |
2911 | if (!selinux_initialized(&selinux_state) || |
2912 | !(sbsec->flags & SBLABEL_MNT)) | |
25a74f3b SS |
2913 | return -EOPNOTSUPP; |
2914 | ||
9548906b TH |
2915 | if (name) |
2916 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 2917 | |
570bc1c2 | 2918 | if (value && len) { |
aa8e712c SS |
2919 | rc = security_sid_to_context_force(&selinux_state, newsid, |
2920 | &context, &clen); | |
9548906b | 2921 | if (rc) |
570bc1c2 | 2922 | return rc; |
570bc1c2 SS |
2923 | *value = context; |
2924 | *len = clen; | |
5e41ff9e | 2925 | } |
5e41ff9e | 2926 | |
5e41ff9e SS |
2927 | return 0; |
2928 | } | |
2929 | ||
4acdaf27 | 2930 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
2931 | { |
2932 | return may_create(dir, dentry, SECCLASS_FILE); | |
2933 | } | |
2934 | ||
1da177e4 LT |
2935 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2936 | { | |
1da177e4 LT |
2937 | return may_link(dir, old_dentry, MAY_LINK); |
2938 | } | |
2939 | ||
1da177e4 LT |
2940 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2941 | { | |
1da177e4 LT |
2942 | return may_link(dir, dentry, MAY_UNLINK); |
2943 | } | |
2944 | ||
2945 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2946 | { | |
2947 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2948 | } | |
2949 | ||
18bb1db3 | 2950 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
2951 | { |
2952 | return may_create(dir, dentry, SECCLASS_DIR); | |
2953 | } | |
2954 | ||
1da177e4 LT |
2955 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2956 | { | |
2957 | return may_link(dir, dentry, MAY_RMDIR); | |
2958 | } | |
2959 | ||
1a67aafb | 2960 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 2961 | { |
1da177e4 LT |
2962 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
2963 | } | |
2964 | ||
1da177e4 | 2965 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 2966 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
2967 | { |
2968 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2969 | } | |
2970 | ||
1da177e4 LT |
2971 | static int selinux_inode_readlink(struct dentry *dentry) |
2972 | { | |
88e67f3b DH |
2973 | const struct cred *cred = current_cred(); |
2974 | ||
2875fa00 | 2975 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
2976 | } |
2977 | ||
bda0be7a N |
2978 | static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, |
2979 | bool rcu) | |
1da177e4 | 2980 | { |
88e67f3b | 2981 | const struct cred *cred = current_cred(); |
bda0be7a N |
2982 | struct common_audit_data ad; |
2983 | struct inode_security_struct *isec; | |
2984 | u32 sid; | |
1da177e4 | 2985 | |
bda0be7a N |
2986 | validate_creds(cred); |
2987 | ||
2988 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
2989 | ad.u.dentry = dentry; | |
2990 | sid = cred_sid(cred); | |
5d226df4 AG |
2991 | isec = inode_security_rcu(inode, rcu); |
2992 | if (IS_ERR(isec)) | |
2993 | return PTR_ERR(isec); | |
bda0be7a | 2994 | |
1a37079c SS |
2995 | return avc_has_perm_flags(&selinux_state, |
2996 | sid, isec->sid, isec->sclass, FILE__READ, &ad, | |
2997 | rcu ? MAY_NOT_BLOCK : 0); | |
1da177e4 LT |
2998 | } |
2999 | ||
d4cf970d EP |
3000 | static noinline int audit_inode_permission(struct inode *inode, |
3001 | u32 perms, u32 audited, u32 denied, | |
0188d5c0 | 3002 | int result) |
1da177e4 | 3003 | { |
b782e0a6 | 3004 | struct common_audit_data ad; |
80788c22 | 3005 | struct inode_security_struct *isec = selinux_inode(inode); |
d4cf970d EP |
3006 | int rc; |
3007 | ||
50c205f5 | 3008 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
3009 | ad.u.inode = inode; |
3010 | ||
6b6bc620 SS |
3011 | rc = slow_avc_audit(&selinux_state, |
3012 | current_sid(), isec->sid, isec->sclass, perms, | |
0188d5c0 | 3013 | audited, denied, result, &ad); |
d4cf970d EP |
3014 | if (rc) |
3015 | return rc; | |
3016 | return 0; | |
3017 | } | |
3018 | ||
e74f71eb | 3019 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 3020 | { |
88e67f3b | 3021 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
3022 | u32 perms; |
3023 | bool from_access; | |
5298d0b9 | 3024 | bool no_block = mask & MAY_NOT_BLOCK; |
2e334057 EP |
3025 | struct inode_security_struct *isec; |
3026 | u32 sid; | |
3027 | struct av_decision avd; | |
3028 | int rc, rc2; | |
3029 | u32 audited, denied; | |
1da177e4 | 3030 | |
b782e0a6 | 3031 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
3032 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
3033 | ||
b782e0a6 EP |
3034 | /* No permission to check. Existence test. */ |
3035 | if (!mask) | |
1da177e4 | 3036 | return 0; |
1da177e4 | 3037 | |
2e334057 | 3038 | validate_creds(cred); |
b782e0a6 | 3039 | |
2e334057 EP |
3040 | if (unlikely(IS_PRIVATE(inode))) |
3041 | return 0; | |
b782e0a6 EP |
3042 | |
3043 | perms = file_mask_to_av(inode->i_mode, mask); | |
3044 | ||
2e334057 | 3045 | sid = cred_sid(cred); |
5298d0b9 | 3046 | isec = inode_security_rcu(inode, no_block); |
5d226df4 AG |
3047 | if (IS_ERR(isec)) |
3048 | return PTR_ERR(isec); | |
2e334057 | 3049 | |
6b6bc620 | 3050 | rc = avc_has_perm_noaudit(&selinux_state, |
3a28cff3 | 3051 | sid, isec->sid, isec->sclass, perms, |
5298d0b9 | 3052 | no_block ? AVC_NONBLOCKING : 0, |
3a28cff3 | 3053 | &avd); |
2e334057 EP |
3054 | audited = avc_audit_required(perms, &avd, rc, |
3055 | from_access ? FILE__AUDIT_ACCESS : 0, | |
3056 | &denied); | |
3057 | if (likely(!audited)) | |
3058 | return rc; | |
3059 | ||
0188d5c0 | 3060 | /* fall back to ref-walk if we have to generate audit */ |
5298d0b9 | 3061 | if (no_block) |
0188d5c0 SS |
3062 | return -ECHILD; |
3063 | ||
3064 | rc2 = audit_inode_permission(inode, perms, audited, denied, rc); | |
2e334057 EP |
3065 | if (rc2) |
3066 | return rc2; | |
3067 | return rc; | |
1da177e4 LT |
3068 | } |
3069 | ||
3070 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
3071 | { | |
88e67f3b | 3072 | const struct cred *cred = current_cred(); |
ccb54478 | 3073 | struct inode *inode = d_backing_inode(dentry); |
bc6a6008 | 3074 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 3075 | __u32 av = FILE__WRITE; |
1da177e4 | 3076 | |
bc6a6008 AW |
3077 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
3078 | if (ia_valid & ATTR_FORCE) { | |
3079 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
3080 | ATTR_FORCE); | |
3081 | if (!ia_valid) | |
3082 | return 0; | |
3083 | } | |
1da177e4 | 3084 | |
bc6a6008 AW |
3085 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
3086 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 3087 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 3088 | |
aa8e712c | 3089 | if (selinux_policycap_openperm() && |
ccb54478 SS |
3090 | inode->i_sb->s_magic != SOCKFS_MAGIC && |
3091 | (ia_valid & ATTR_SIZE) && | |
3092 | !(ia_valid & ATTR_FILE)) | |
95dbf739 EP |
3093 | av |= FILE__OPEN; |
3094 | ||
3095 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
3096 | } |
3097 | ||
3f7036a0 | 3098 | static int selinux_inode_getattr(const struct path *path) |
1da177e4 | 3099 | { |
3f7036a0 | 3100 | return path_has_perm(current_cred(), path, FILE__GETATTR); |
1da177e4 LT |
3101 | } |
3102 | ||
db59000a SS |
3103 | static bool has_cap_mac_admin(bool audit) |
3104 | { | |
3105 | const struct cred *cred = current_cred(); | |
c1a85a00 | 3106 | unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; |
db59000a | 3107 | |
c1a85a00 | 3108 | if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) |
db59000a | 3109 | return false; |
c1a85a00 | 3110 | if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) |
db59000a SS |
3111 | return false; |
3112 | return true; | |
3113 | } | |
3114 | ||
8f0cfa52 DH |
3115 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
3116 | const void *value, size_t size, int flags) | |
1da177e4 | 3117 | { |
c6f493d6 | 3118 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3119 | struct inode_security_struct *isec; |
1da177e4 | 3120 | struct superblock_security_struct *sbsec; |
2bf49690 | 3121 | struct common_audit_data ad; |
275bb41e | 3122 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
3123 | int rc = 0; |
3124 | ||
6b240306 EB |
3125 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3126 | rc = cap_inode_setxattr(dentry, name, value, size, flags); | |
3127 | if (rc) | |
3128 | return rc; | |
3129 | ||
3130 | /* Not an attribute we recognize, so just check the | |
3131 | ordinary setattr permission. */ | |
3132 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3133 | } | |
1da177e4 | 3134 | |
65cddd50 | 3135 | if (!selinux_initialized(&selinux_state)) |
3e3e24b4 JL |
3136 | return (inode_owner_or_capable(inode) ? 0 : -EPERM); |
3137 | ||
1da177e4 | 3138 | sbsec = inode->i_sb->s_security; |
12f348b9 | 3139 | if (!(sbsec->flags & SBLABEL_MNT)) |
1da177e4 LT |
3140 | return -EOPNOTSUPP; |
3141 | ||
2e149670 | 3142 | if (!inode_owner_or_capable(inode)) |
1da177e4 LT |
3143 | return -EPERM; |
3144 | ||
50c205f5 | 3145 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 3146 | ad.u.dentry = dentry; |
1da177e4 | 3147 | |
20cdef8d | 3148 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
3149 | rc = avc_has_perm(&selinux_state, |
3150 | sid, isec->sid, isec->sclass, | |
1da177e4 LT |
3151 | FILE__RELABELFROM, &ad); |
3152 | if (rc) | |
3153 | return rc; | |
3154 | ||
aa8e712c SS |
3155 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3156 | GFP_KERNEL); | |
12b29f34 | 3157 | if (rc == -EINVAL) { |
db59000a | 3158 | if (!has_cap_mac_admin(true)) { |
d6ea83ec EP |
3159 | struct audit_buffer *ab; |
3160 | size_t audit_size; | |
d6ea83ec EP |
3161 | |
3162 | /* We strip a nul only if it is at the end, otherwise the | |
3163 | * context contains a nul and we should audit that */ | |
e3fea3f7 | 3164 | if (value) { |
add24372 CIK |
3165 | const char *str = value; |
3166 | ||
e3fea3f7 AV |
3167 | if (str[size - 1] == '\0') |
3168 | audit_size = size - 1; | |
3169 | else | |
3170 | audit_size = size; | |
3171 | } else { | |
e3fea3f7 AV |
3172 | audit_size = 0; |
3173 | } | |
cdfb6b34 RGB |
3174 | ab = audit_log_start(audit_context(), |
3175 | GFP_ATOMIC, AUDIT_SELINUX_ERR); | |
d6ea83ec EP |
3176 | audit_log_format(ab, "op=setxattr invalid_context="); |
3177 | audit_log_n_untrustedstring(ab, value, audit_size); | |
3178 | audit_log_end(ab); | |
3179 | ||
12b29f34 | 3180 | return rc; |
d6ea83ec | 3181 | } |
aa8e712c SS |
3182 | rc = security_context_to_sid_force(&selinux_state, value, |
3183 | size, &newsid); | |
12b29f34 | 3184 | } |
1da177e4 LT |
3185 | if (rc) |
3186 | return rc; | |
3187 | ||
6b6bc620 SS |
3188 | rc = avc_has_perm(&selinux_state, |
3189 | sid, newsid, isec->sclass, | |
1da177e4 LT |
3190 | FILE__RELABELTO, &ad); |
3191 | if (rc) | |
3192 | return rc; | |
3193 | ||
aa8e712c SS |
3194 | rc = security_validate_transition(&selinux_state, isec->sid, newsid, |
3195 | sid, isec->sclass); | |
1da177e4 LT |
3196 | if (rc) |
3197 | return rc; | |
3198 | ||
6b6bc620 SS |
3199 | return avc_has_perm(&selinux_state, |
3200 | newsid, | |
1da177e4 LT |
3201 | sbsec->sid, |
3202 | SECCLASS_FILESYSTEM, | |
3203 | FILESYSTEM__ASSOCIATE, | |
3204 | &ad); | |
3205 | } | |
3206 | ||
8f0cfa52 | 3207 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 3208 | const void *value, size_t size, |
8f0cfa52 | 3209 | int flags) |
1da177e4 | 3210 | { |
c6f493d6 | 3211 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3212 | struct inode_security_struct *isec; |
1da177e4 LT |
3213 | u32 newsid; |
3214 | int rc; | |
3215 | ||
3216 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
3217 | /* Not an attribute we recognize, so nothing to do. */ | |
3218 | return; | |
3219 | } | |
3220 | ||
65cddd50 | 3221 | if (!selinux_initialized(&selinux_state)) { |
3e3e24b4 JL |
3222 | /* If we haven't even been initialized, then we can't validate |
3223 | * against a policy, so leave the label as invalid. It may | |
3224 | * resolve to a valid label on the next revalidation try if | |
3225 | * we've since initialized. | |
3226 | */ | |
3227 | return; | |
3228 | } | |
3229 | ||
aa8e712c SS |
3230 | rc = security_context_to_sid_force(&selinux_state, value, size, |
3231 | &newsid); | |
1da177e4 | 3232 | if (rc) { |
c103a91e | 3233 | pr_err("SELinux: unable to map context to SID" |
12b29f34 SS |
3234 | "for (%s, %lu), rc=%d\n", |
3235 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
3236 | return; |
3237 | } | |
3238 | ||
20cdef8d | 3239 | isec = backing_inode_security(dentry); |
9287aed2 | 3240 | spin_lock(&isec->lock); |
aa9c2669 | 3241 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3242 | isec->sid = newsid; |
6f3be9f5 | 3243 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3244 | spin_unlock(&isec->lock); |
aa9c2669 | 3245 | |
1da177e4 LT |
3246 | return; |
3247 | } | |
3248 | ||
8f0cfa52 | 3249 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 3250 | { |
88e67f3b DH |
3251 | const struct cred *cred = current_cred(); |
3252 | ||
2875fa00 | 3253 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3254 | } |
3255 | ||
828dfe1d | 3256 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 3257 | { |
88e67f3b DH |
3258 | const struct cred *cred = current_cred(); |
3259 | ||
2875fa00 | 3260 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3261 | } |
3262 | ||
8f0cfa52 | 3263 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 3264 | { |
6b240306 EB |
3265 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3266 | int rc = cap_inode_removexattr(dentry, name); | |
3267 | if (rc) | |
3268 | return rc; | |
3269 | ||
3270 | /* Not an attribute we recognize, so just check the | |
3271 | ordinary setattr permission. */ | |
3272 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3273 | } | |
1da177e4 | 3274 | |
9530a3e0 SS |
3275 | if (!selinux_initialized(&selinux_state)) |
3276 | return 0; | |
3277 | ||
1da177e4 LT |
3278 | /* No one is allowed to remove a SELinux security label. |
3279 | You can change the label, but all data must be labeled. */ | |
3280 | return -EACCES; | |
3281 | } | |
3282 | ||
ac5656d8 AG |
3283 | static int selinux_path_notify(const struct path *path, u64 mask, |
3284 | unsigned int obj_type) | |
3285 | { | |
3286 | int ret; | |
3287 | u32 perm; | |
3288 | ||
3289 | struct common_audit_data ad; | |
3290 | ||
3291 | ad.type = LSM_AUDIT_DATA_PATH; | |
3292 | ad.u.path = *path; | |
3293 | ||
3294 | /* | |
3295 | * Set permission needed based on the type of mark being set. | |
3296 | * Performs an additional check for sb watches. | |
3297 | */ | |
3298 | switch (obj_type) { | |
3299 | case FSNOTIFY_OBJ_TYPE_VFSMOUNT: | |
3300 | perm = FILE__WATCH_MOUNT; | |
3301 | break; | |
3302 | case FSNOTIFY_OBJ_TYPE_SB: | |
3303 | perm = FILE__WATCH_SB; | |
3304 | ret = superblock_has_perm(current_cred(), path->dentry->d_sb, | |
3305 | FILESYSTEM__WATCH, &ad); | |
3306 | if (ret) | |
3307 | return ret; | |
3308 | break; | |
3309 | case FSNOTIFY_OBJ_TYPE_INODE: | |
3310 | perm = FILE__WATCH; | |
3311 | break; | |
3312 | default: | |
3313 | return -EINVAL; | |
3314 | } | |
3315 | ||
3316 | /* blocking watches require the file:watch_with_perm permission */ | |
3317 | if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) | |
3318 | perm |= FILE__WATCH_WITH_PERM; | |
3319 | ||
3320 | /* watches on read-like events need the file:watch_reads permission */ | |
3321 | if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) | |
3322 | perm |= FILE__WATCH_READS; | |
3323 | ||
3324 | return path_has_perm(current_cred(), path, perm); | |
3325 | } | |
3326 | ||
d381d8a9 | 3327 | /* |
abc69bb6 | 3328 | * Copy the inode security context value to the user. |
d381d8a9 JM |
3329 | * |
3330 | * Permission check is handled by selinux_inode_getxattr hook. | |
3331 | */ | |
ea861dfd | 3332 | static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 3333 | { |
42492594 DQ |
3334 | u32 size; |
3335 | int error; | |
3336 | char *context = NULL; | |
20cdef8d | 3337 | struct inode_security_struct *isec; |
d381d8a9 | 3338 | |
c8e22261 JL |
3339 | /* |
3340 | * If we're not initialized yet, then we can't validate contexts, so | |
3341 | * just let vfs_getxattr fall back to using the on-disk xattr. | |
3342 | */ | |
3343 | if (!selinux_initialized(&selinux_state) || | |
3344 | strcmp(name, XATTR_SELINUX_SUFFIX)) | |
8c8570fb | 3345 | return -EOPNOTSUPP; |
d381d8a9 | 3346 | |
abc69bb6 SS |
3347 | /* |
3348 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3349 | * value even if it is not defined by current policy; otherwise, | |
3350 | * use the in-core value under current policy. | |
3351 | * Use the non-auditing forms of the permission checks since | |
3352 | * getxattr may be called by unprivileged processes commonly | |
3353 | * and lack of permission just means that we fall back to the | |
3354 | * in-core context value, not a denial. | |
3355 | */ | |
20cdef8d | 3356 | isec = inode_security(inode); |
db59000a | 3357 | if (has_cap_mac_admin(false)) |
aa8e712c SS |
3358 | error = security_sid_to_context_force(&selinux_state, |
3359 | isec->sid, &context, | |
abc69bb6 SS |
3360 | &size); |
3361 | else | |
aa8e712c SS |
3362 | error = security_sid_to_context(&selinux_state, isec->sid, |
3363 | &context, &size); | |
42492594 DQ |
3364 | if (error) |
3365 | return error; | |
3366 | error = size; | |
3367 | if (alloc) { | |
3368 | *buffer = context; | |
3369 | goto out_nofree; | |
3370 | } | |
3371 | kfree(context); | |
3372 | out_nofree: | |
3373 | return error; | |
1da177e4 LT |
3374 | } |
3375 | ||
3376 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 3377 | const void *value, size_t size, int flags) |
1da177e4 | 3378 | { |
2c97165b | 3379 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
53e0c2aa | 3380 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; |
1da177e4 LT |
3381 | u32 newsid; |
3382 | int rc; | |
3383 | ||
3384 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3385 | return -EOPNOTSUPP; | |
3386 | ||
53e0c2aa OM |
3387 | if (!(sbsec->flags & SBLABEL_MNT)) |
3388 | return -EOPNOTSUPP; | |
3389 | ||
1da177e4 LT |
3390 | if (!value || !size) |
3391 | return -EACCES; | |
3392 | ||
aa8e712c SS |
3393 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3394 | GFP_KERNEL); | |
1da177e4 LT |
3395 | if (rc) |
3396 | return rc; | |
3397 | ||
9287aed2 | 3398 | spin_lock(&isec->lock); |
aa9c2669 | 3399 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3400 | isec->sid = newsid; |
6f3be9f5 | 3401 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3402 | spin_unlock(&isec->lock); |
1da177e4 LT |
3403 | return 0; |
3404 | } | |
3405 | ||
3406 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3407 | { | |
3408 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3409 | if (buffer && len <= buffer_size) | |
3410 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3411 | return len; | |
3412 | } | |
3413 | ||
d6335d77 | 3414 | static void selinux_inode_getsecid(struct inode *inode, u32 *secid) |
713a04ae | 3415 | { |
e817c2f3 | 3416 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
713a04ae AD |
3417 | *secid = isec->sid; |
3418 | } | |
3419 | ||
56909eb3 VG |
3420 | static int selinux_inode_copy_up(struct dentry *src, struct cred **new) |
3421 | { | |
3422 | u32 sid; | |
3423 | struct task_security_struct *tsec; | |
3424 | struct cred *new_creds = *new; | |
3425 | ||
3426 | if (new_creds == NULL) { | |
3427 | new_creds = prepare_creds(); | |
3428 | if (!new_creds) | |
3429 | return -ENOMEM; | |
3430 | } | |
3431 | ||
0c6cfa62 | 3432 | tsec = selinux_cred(new_creds); |
56909eb3 VG |
3433 | /* Get label from overlay inode and set it in create_sid */ |
3434 | selinux_inode_getsecid(d_inode(src), &sid); | |
3435 | tsec->create_sid = sid; | |
3436 | *new = new_creds; | |
3437 | return 0; | |
3438 | } | |
3439 | ||
19472b69 VG |
3440 | static int selinux_inode_copy_up_xattr(const char *name) |
3441 | { | |
3442 | /* The copy_up hook above sets the initial context on an inode, but we | |
3443 | * don't then want to overwrite it by blindly copying all the lower | |
3444 | * xattrs up. Instead, we have to filter out SELinux-related xattrs. | |
3445 | */ | |
3446 | if (strcmp(name, XATTR_NAME_SELINUX) == 0) | |
3447 | return 1; /* Discard */ | |
3448 | /* | |
3449 | * Any other attribute apart from SELINUX is not claimed, supported | |
3450 | * by selinux. | |
3451 | */ | |
3452 | return -EOPNOTSUPP; | |
3453 | } | |
3454 | ||
ec882da5 OM |
3455 | /* kernfs node operations */ |
3456 | ||
c72c4cde Y |
3457 | static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, |
3458 | struct kernfs_node *kn) | |
ec882da5 | 3459 | { |
169ce0c0 | 3460 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
ec882da5 OM |
3461 | u32 parent_sid, newsid, clen; |
3462 | int rc; | |
3463 | char *context; | |
3464 | ||
1537ad15 | 3465 | rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); |
ec882da5 OM |
3466 | if (rc == -ENODATA) |
3467 | return 0; | |
3468 | else if (rc < 0) | |
3469 | return rc; | |
3470 | ||
3471 | clen = (u32)rc; | |
3472 | context = kmalloc(clen, GFP_KERNEL); | |
3473 | if (!context) | |
3474 | return -ENOMEM; | |
3475 | ||
1537ad15 | 3476 | rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); |
ec882da5 OM |
3477 | if (rc < 0) { |
3478 | kfree(context); | |
3479 | return rc; | |
3480 | } | |
3481 | ||
3482 | rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid, | |
3483 | GFP_KERNEL); | |
3484 | kfree(context); | |
3485 | if (rc) | |
3486 | return rc; | |
3487 | ||
3488 | if (tsec->create_sid) { | |
3489 | newsid = tsec->create_sid; | |
3490 | } else { | |
3491 | u16 secclass = inode_mode_to_security_class(kn->mode); | |
3492 | struct qstr q; | |
3493 | ||
3494 | q.name = kn->name; | |
3495 | q.hash_len = hashlen_string(kn_dir, kn->name); | |
3496 | ||
3497 | rc = security_transition_sid(&selinux_state, tsec->sid, | |
3498 | parent_sid, secclass, &q, | |
3499 | &newsid); | |
3500 | if (rc) | |
3501 | return rc; | |
3502 | } | |
3503 | ||
3504 | rc = security_sid_to_context_force(&selinux_state, newsid, | |
3505 | &context, &clen); | |
3506 | if (rc) | |
3507 | return rc; | |
3508 | ||
1537ad15 OM |
3509 | rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, |
3510 | XATTR_CREATE); | |
ec882da5 OM |
3511 | kfree(context); |
3512 | return rc; | |
3513 | } | |
3514 | ||
3515 | ||
1da177e4 LT |
3516 | /* file security operations */ |
3517 | ||
788e7dd4 | 3518 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3519 | { |
88e67f3b | 3520 | const struct cred *cred = current_cred(); |
496ad9aa | 3521 | struct inode *inode = file_inode(file); |
1da177e4 | 3522 | |
1da177e4 LT |
3523 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3524 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3525 | mask |= MAY_APPEND; | |
3526 | ||
389fb800 PM |
3527 | return file_has_perm(cred, file, |
3528 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3529 | } |
3530 | ||
788e7dd4 YN |
3531 | static int selinux_file_permission(struct file *file, int mask) |
3532 | { | |
496ad9aa | 3533 | struct inode *inode = file_inode(file); |
bb6c6b02 | 3534 | struct file_security_struct *fsec = selinux_file(file); |
b197367e | 3535 | struct inode_security_struct *isec; |
20dda18b SS |
3536 | u32 sid = current_sid(); |
3537 | ||
389fb800 | 3538 | if (!mask) |
788e7dd4 YN |
3539 | /* No permission to check. Existence test. */ |
3540 | return 0; | |
788e7dd4 | 3541 | |
b197367e | 3542 | isec = inode_security(inode); |
20dda18b | 3543 | if (sid == fsec->sid && fsec->isid == isec->sid && |
6b6bc620 | 3544 | fsec->pseqno == avc_policy_seqno(&selinux_state)) |
83d49856 | 3545 | /* No change since file_open check. */ |
20dda18b SS |
3546 | return 0; |
3547 | ||
788e7dd4 YN |
3548 | return selinux_revalidate_file_permission(file, mask); |
3549 | } | |
3550 | ||
1da177e4 LT |
3551 | static int selinux_file_alloc_security(struct file *file) |
3552 | { | |
cb89e246 PM |
3553 | struct file_security_struct *fsec = selinux_file(file); |
3554 | u32 sid = current_sid(); | |
3555 | ||
3556 | fsec->sid = sid; | |
3557 | fsec->fown_sid = sid; | |
3558 | ||
3559 | return 0; | |
1da177e4 LT |
3560 | } |
3561 | ||
fa1aa143 JVS |
3562 | /* |
3563 | * Check whether a task has the ioctl permission and cmd | |
3564 | * operation to an inode. | |
3565 | */ | |
1d2a168a | 3566 | static int ioctl_has_perm(const struct cred *cred, struct file *file, |
fa1aa143 JVS |
3567 | u32 requested, u16 cmd) |
3568 | { | |
3569 | struct common_audit_data ad; | |
bb6c6b02 | 3570 | struct file_security_struct *fsec = selinux_file(file); |
fa1aa143 | 3571 | struct inode *inode = file_inode(file); |
20cdef8d | 3572 | struct inode_security_struct *isec; |
fa1aa143 JVS |
3573 | struct lsm_ioctlop_audit ioctl; |
3574 | u32 ssid = cred_sid(cred); | |
3575 | int rc; | |
3576 | u8 driver = cmd >> 8; | |
3577 | u8 xperm = cmd & 0xff; | |
3578 | ||
3579 | ad.type = LSM_AUDIT_DATA_IOCTL_OP; | |
3580 | ad.u.op = &ioctl; | |
3581 | ad.u.op->cmd = cmd; | |
3582 | ad.u.op->path = file->f_path; | |
3583 | ||
3584 | if (ssid != fsec->sid) { | |
6b6bc620 SS |
3585 | rc = avc_has_perm(&selinux_state, |
3586 | ssid, fsec->sid, | |
fa1aa143 JVS |
3587 | SECCLASS_FD, |
3588 | FD__USE, | |
3589 | &ad); | |
3590 | if (rc) | |
3591 | goto out; | |
3592 | } | |
3593 | ||
3594 | if (unlikely(IS_PRIVATE(inode))) | |
3595 | return 0; | |
3596 | ||
20cdef8d | 3597 | isec = inode_security(inode); |
6b6bc620 SS |
3598 | rc = avc_has_extended_perms(&selinux_state, |
3599 | ssid, isec->sid, isec->sclass, | |
3600 | requested, driver, xperm, &ad); | |
fa1aa143 JVS |
3601 | out: |
3602 | return rc; | |
3603 | } | |
3604 | ||
1da177e4 LT |
3605 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
3606 | unsigned long arg) | |
3607 | { | |
88e67f3b | 3608 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3609 | int error = 0; |
1da177e4 | 3610 | |
0b24dcb7 EP |
3611 | switch (cmd) { |
3612 | case FIONREAD: | |
0b24dcb7 | 3613 | case FIBMAP: |
0b24dcb7 | 3614 | case FIGETBSZ: |
2f99c369 | 3615 | case FS_IOC_GETFLAGS: |
2f99c369 | 3616 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3617 | error = file_has_perm(cred, file, FILE__GETATTR); |
3618 | break; | |
1da177e4 | 3619 | |
2f99c369 | 3620 | case FS_IOC_SETFLAGS: |
2f99c369 | 3621 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3622 | error = file_has_perm(cred, file, FILE__SETATTR); |
3623 | break; | |
3624 | ||
3625 | /* sys_ioctl() checks */ | |
3626 | case FIONBIO: | |
0b24dcb7 EP |
3627 | case FIOASYNC: |
3628 | error = file_has_perm(cred, file, 0); | |
3629 | break; | |
1da177e4 | 3630 | |
0b24dcb7 EP |
3631 | case KDSKBENT: |
3632 | case KDSKBSENT: | |
6a9de491 | 3633 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
c1a85a00 | 3634 | CAP_OPT_NONE, true); |
0b24dcb7 EP |
3635 | break; |
3636 | ||
3637 | /* default case assumes that the command will go | |
3638 | * to the file's ioctl() function. | |
3639 | */ | |
3640 | default: | |
fa1aa143 | 3641 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
0b24dcb7 EP |
3642 | } |
3643 | return error; | |
1da177e4 LT |
3644 | } |
3645 | ||
b78b7d59 | 3646 | static int default_noexec __ro_after_init; |
fcaaade1 | 3647 | |
1da177e4 LT |
3648 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3649 | { | |
88e67f3b | 3650 | const struct cred *cred = current_cred(); |
be0554c9 | 3651 | u32 sid = cred_sid(cred); |
d84f4f99 | 3652 | int rc = 0; |
88e67f3b | 3653 | |
fcaaade1 | 3654 | if (default_noexec && |
892e8cac SS |
3655 | (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || |
3656 | (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3657 | /* |
3658 | * We are making executable an anonymous mapping or a | |
3659 | * private file mapping that will also be writable. | |
3660 | * This has an additional check. | |
3661 | */ | |
6b6bc620 SS |
3662 | rc = avc_has_perm(&selinux_state, |
3663 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3664 | PROCESS__EXECMEM, NULL); |
1da177e4 | 3665 | if (rc) |
d84f4f99 | 3666 | goto error; |
1da177e4 | 3667 | } |
1da177e4 LT |
3668 | |
3669 | if (file) { | |
3670 | /* read access is always possible with a mapping */ | |
3671 | u32 av = FILE__READ; | |
3672 | ||
3673 | /* write access only matters if the mapping is shared */ | |
3674 | if (shared && (prot & PROT_WRITE)) | |
3675 | av |= FILE__WRITE; | |
3676 | ||
3677 | if (prot & PROT_EXEC) | |
3678 | av |= FILE__EXECUTE; | |
3679 | ||
88e67f3b | 3680 | return file_has_perm(cred, file, av); |
1da177e4 | 3681 | } |
d84f4f99 DH |
3682 | |
3683 | error: | |
3684 | return rc; | |
1da177e4 LT |
3685 | } |
3686 | ||
e5467859 | 3687 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3688 | { |
b1d9e6b0 | 3689 | int rc = 0; |
1da177e4 | 3690 | |
a2551df7 | 3691 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
98883bfd | 3692 | u32 sid = current_sid(); |
6b6bc620 SS |
3693 | rc = avc_has_perm(&selinux_state, |
3694 | sid, sid, SECCLASS_MEMPROTECT, | |
ed032189 | 3695 | MEMPROTECT__MMAP_ZERO, NULL); |
84336d1a EP |
3696 | } |
3697 | ||
98883bfd | 3698 | return rc; |
e5467859 | 3699 | } |
1da177e4 | 3700 | |
e5467859 AV |
3701 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3702 | unsigned long prot, unsigned long flags) | |
3703 | { | |
3ba4bf5f SS |
3704 | struct common_audit_data ad; |
3705 | int rc; | |
3706 | ||
3707 | if (file) { | |
3708 | ad.type = LSM_AUDIT_DATA_FILE; | |
3709 | ad.u.file = file; | |
3710 | rc = inode_has_perm(current_cred(), file_inode(file), | |
3711 | FILE__MAP, &ad); | |
3712 | if (rc) | |
3713 | return rc; | |
3714 | } | |
3715 | ||
8861d0af | 3716 | if (checkreqprot_get(&selinux_state)) |
1da177e4 LT |
3717 | prot = reqprot; |
3718 | ||
3719 | return file_map_prot_check(file, prot, | |
3720 | (flags & MAP_TYPE) == MAP_SHARED); | |
3721 | } | |
3722 | ||
3723 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3724 | unsigned long reqprot, | |
3725 | unsigned long prot) | |
3726 | { | |
88e67f3b | 3727 | const struct cred *cred = current_cred(); |
be0554c9 | 3728 | u32 sid = cred_sid(cred); |
1da177e4 | 3729 | |
8861d0af | 3730 | if (checkreqprot_get(&selinux_state)) |
1da177e4 LT |
3731 | prot = reqprot; |
3732 | ||
fcaaade1 SS |
3733 | if (default_noexec && |
3734 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3735 | int rc = 0; |
db4c9641 SS |
3736 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3737 | vma->vm_end <= vma->vm_mm->brk) { | |
6b6bc620 SS |
3738 | rc = avc_has_perm(&selinux_state, |
3739 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3740 | PROCESS__EXECHEAP, NULL); |
db4c9641 | 3741 | } else if (!vma->vm_file && |
c2316dbf SS |
3742 | ((vma->vm_start <= vma->vm_mm->start_stack && |
3743 | vma->vm_end >= vma->vm_mm->start_stack) || | |
d17af505 | 3744 | vma_is_stack_for_current(vma))) { |
6b6bc620 SS |
3745 | rc = avc_has_perm(&selinux_state, |
3746 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3747 | PROCESS__EXECSTACK, NULL); |
db4c9641 SS |
3748 | } else if (vma->vm_file && vma->anon_vma) { |
3749 | /* | |
3750 | * We are making executable a file mapping that has | |
3751 | * had some COW done. Since pages might have been | |
3752 | * written, check ability to execute the possibly | |
3753 | * modified content. This typically should only | |
3754 | * occur for text relocations. | |
3755 | */ | |
d84f4f99 | 3756 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3757 | } |