]>
Commit | Line | Data |
---|---|---|
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; |
b159e86b | 603 | struct dentry *root = 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) { | |
b159e86b | 1083 | struct dentry *root = sb->s_root; |
e3489f89 AV |
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 | */ | |
200ea5a2 | 1454 | goto out_invalid; |
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) | |
200ea5a2 | 1511 | goto out_invalid; |
9287aed2 | 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) { | |
200ea5a2 | 1536 | if (rc) { |
9287aed2 AG |
1537 | isec->initialized = LABEL_INVALID; |
1538 | goto out_unlock; | |
1539 | } | |
9287aed2 AG |
1540 | isec->initialized = LABEL_INITIALIZED; |
1541 | isec->sid = sid; | |
1542 | } | |
1da177e4 | 1543 | |
23970741 | 1544 | out_unlock: |
9287aed2 | 1545 | spin_unlock(&isec->lock); |
1da177e4 | 1546 | return rc; |
200ea5a2 PM |
1547 | |
1548 | out_invalid: | |
1549 | spin_lock(&isec->lock); | |
1550 | if (isec->initialized == LABEL_PENDING) { | |
1551 | isec->initialized = LABEL_INVALID; | |
1552 | isec->sid = sid; | |
1553 | } | |
1554 | spin_unlock(&isec->lock); | |
1555 | return 0; | |
1da177e4 LT |
1556 | } |
1557 | ||
1558 | /* Convert a Linux signal to an access vector. */ | |
1559 | static inline u32 signal_to_av(int sig) | |
1560 | { | |
1561 | u32 perm = 0; | |
1562 | ||
1563 | switch (sig) { | |
1564 | case SIGCHLD: | |
1565 | /* Commonly granted from child to parent. */ | |
1566 | perm = PROCESS__SIGCHLD; | |
1567 | break; | |
1568 | case SIGKILL: | |
1569 | /* Cannot be caught or ignored */ | |
1570 | perm = PROCESS__SIGKILL; | |
1571 | break; | |
1572 | case SIGSTOP: | |
1573 | /* Cannot be caught or ignored */ | |
1574 | perm = PROCESS__SIGSTOP; | |
1575 | break; | |
1576 | default: | |
1577 | /* All other signals. */ | |
1578 | perm = PROCESS__SIGNAL; | |
1579 | break; | |
1580 | } | |
1581 | ||
1582 | return perm; | |
1583 | } | |
1584 | ||
b68e418c SS |
1585 | #if CAP_LAST_CAP > 63 |
1586 | #error Fix SELinux to handle capabilities > 63. | |
1587 | #endif | |
1588 | ||
1da177e4 | 1589 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1590 | static int cred_has_capability(const struct cred *cred, |
c1a85a00 | 1591 | int cap, unsigned int opts, bool initns) |
1da177e4 | 1592 | { |
2bf49690 | 1593 | struct common_audit_data ad; |
06112163 | 1594 | struct av_decision avd; |
b68e418c | 1595 | u16 sclass; |
3699c53c | 1596 | u32 sid = cred_sid(cred); |
b68e418c | 1597 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1598 | int rc; |
1da177e4 | 1599 | |
50c205f5 | 1600 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1601 | ad.u.cap = cap; |
1602 | ||
b68e418c SS |
1603 | switch (CAP_TO_INDEX(cap)) { |
1604 | case 0: | |
8e4ff6f2 | 1605 | sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; |
b68e418c SS |
1606 | break; |
1607 | case 1: | |
8e4ff6f2 | 1608 | sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; |
b68e418c SS |
1609 | break; |
1610 | default: | |
c103a91e | 1611 | pr_err("SELinux: out of range capability %d\n", cap); |
b68e418c | 1612 | BUG(); |
a35c6c83 | 1613 | return -EINVAL; |
b68e418c | 1614 | } |
06112163 | 1615 | |
6b6bc620 SS |
1616 | rc = avc_has_perm_noaudit(&selinux_state, |
1617 | sid, sid, sclass, av, 0, &avd); | |
c1a85a00 | 1618 | if (!(opts & CAP_OPT_NOAUDIT)) { |
6b6bc620 SS |
1619 | int rc2 = avc_audit(&selinux_state, |
1620 | sid, sid, sclass, av, &avd, rc, &ad, 0); | |
9ade0cf4 EP |
1621 | if (rc2) |
1622 | return rc2; | |
1623 | } | |
06112163 | 1624 | return rc; |
1da177e4 LT |
1625 | } |
1626 | ||
1da177e4 LT |
1627 | /* Check whether a task has a particular permission to an inode. |
1628 | The 'adp' parameter is optional and allows other audit | |
1629 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1630 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1631 | struct inode *inode, |
1632 | u32 perms, | |
19e49834 | 1633 | struct common_audit_data *adp) |
1da177e4 | 1634 | { |
1da177e4 | 1635 | struct inode_security_struct *isec; |
275bb41e | 1636 | u32 sid; |
1da177e4 | 1637 | |
e0e81739 DH |
1638 | validate_creds(cred); |
1639 | ||
828dfe1d | 1640 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1641 | return 0; |
1642 | ||
88e67f3b | 1643 | sid = cred_sid(cred); |
80788c22 | 1644 | isec = selinux_inode(inode); |
1da177e4 | 1645 | |
6b6bc620 SS |
1646 | return avc_has_perm(&selinux_state, |
1647 | sid, isec->sid, isec->sclass, perms, adp); | |
1da177e4 LT |
1648 | } |
1649 | ||
1650 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1651 | the dentry to help the auditing code to more easily generate the | |
1652 | pathname if needed. */ | |
88e67f3b | 1653 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1654 | struct dentry *dentry, |
1655 | u32 av) | |
1656 | { | |
c6f493d6 | 1657 | struct inode *inode = d_backing_inode(dentry); |
2bf49690 | 1658 | struct common_audit_data ad; |
88e67f3b | 1659 | |
50c205f5 | 1660 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1661 | ad.u.dentry = dentry; |
5d226df4 | 1662 | __inode_security_revalidate(inode, dentry, true); |
19e49834 | 1663 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1664 | } |
1665 | ||
1666 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1667 | the path to help the auditing code to more easily generate the | |
1668 | pathname if needed. */ | |
1669 | static inline int path_has_perm(const struct cred *cred, | |
3f7036a0 | 1670 | const struct path *path, |
2875fa00 EP |
1671 | u32 av) |
1672 | { | |
c6f493d6 | 1673 | struct inode *inode = d_backing_inode(path->dentry); |
2875fa00 EP |
1674 | struct common_audit_data ad; |
1675 | ||
50c205f5 | 1676 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1677 | ad.u.path = *path; |
5d226df4 | 1678 | __inode_security_revalidate(inode, path->dentry, true); |
19e49834 | 1679 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1680 | } |
1681 | ||
13f8e981 DH |
1682 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1683 | static inline int file_path_has_perm(const struct cred *cred, | |
1684 | struct file *file, | |
1685 | u32 av) | |
1686 | { | |
1687 | struct common_audit_data ad; | |
1688 | ||
43af5de7 VG |
1689 | ad.type = LSM_AUDIT_DATA_FILE; |
1690 | ad.u.file = file; | |
19e49834 | 1691 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1692 | } |
1693 | ||
f66e448c CF |
1694 | #ifdef CONFIG_BPF_SYSCALL |
1695 | static int bpf_fd_pass(struct file *file, u32 sid); | |
1696 | #endif | |
1697 | ||
1da177e4 LT |
1698 | /* Check whether a task can use an open file descriptor to |
1699 | access an inode in a given way. Check access to the | |
1700 | descriptor itself, and then use dentry_has_perm to | |
1701 | check a particular permission to the file. | |
1702 | Access to the descriptor is implicitly granted if it | |
1703 | has the same SID as the process. If av is zero, then | |
1704 | access to the file is not checked, e.g. for cases | |
1705 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1706 | static int file_has_perm(const struct cred *cred, |
1707 | struct file *file, | |
1708 | u32 av) | |
1da177e4 | 1709 | { |
bb6c6b02 | 1710 | struct file_security_struct *fsec = selinux_file(file); |
496ad9aa | 1711 | struct inode *inode = file_inode(file); |
2bf49690 | 1712 | struct common_audit_data ad; |
88e67f3b | 1713 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1714 | int rc; |
1715 | ||
43af5de7 VG |
1716 | ad.type = LSM_AUDIT_DATA_FILE; |
1717 | ad.u.file = file; | |
1da177e4 | 1718 | |
275bb41e | 1719 | if (sid != fsec->sid) { |
6b6bc620 SS |
1720 | rc = avc_has_perm(&selinux_state, |
1721 | sid, fsec->sid, | |
1da177e4 LT |
1722 | SECCLASS_FD, |
1723 | FD__USE, | |
1724 | &ad); | |
1725 | if (rc) | |
88e67f3b | 1726 | goto out; |
1da177e4 LT |
1727 | } |
1728 | ||
f66e448c CF |
1729 | #ifdef CONFIG_BPF_SYSCALL |
1730 | rc = bpf_fd_pass(file, cred_sid(cred)); | |
1731 | if (rc) | |
1732 | return rc; | |
1733 | #endif | |
1734 | ||
1da177e4 | 1735 | /* av is zero if only checking access to the descriptor. */ |
88e67f3b | 1736 | rc = 0; |
1da177e4 | 1737 | if (av) |
19e49834 | 1738 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1739 | |
88e67f3b DH |
1740 | out: |
1741 | return rc; | |
1da177e4 LT |
1742 | } |
1743 | ||
c3c188b2 DH |
1744 | /* |
1745 | * Determine the label for an inode that might be unioned. | |
1746 | */ | |
c957f6df VG |
1747 | static int |
1748 | selinux_determine_inode_label(const struct task_security_struct *tsec, | |
1749 | struct inode *dir, | |
1750 | const struct qstr *name, u16 tclass, | |
1751 | u32 *_new_isid) | |
c3c188b2 DH |
1752 | { |
1753 | const struct superblock_security_struct *sbsec = dir->i_sb->s_security; | |
c3c188b2 DH |
1754 | |
1755 | if ((sbsec->flags & SE_SBINITIALIZED) && | |
1756 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { | |
1757 | *_new_isid = sbsec->mntpoint_sid; | |
1758 | } else if ((sbsec->flags & SBLABEL_MNT) && | |
1759 | tsec->create_sid) { | |
1760 | *_new_isid = tsec->create_sid; | |
1761 | } else { | |
20cdef8d | 1762 | const struct inode_security_struct *dsec = inode_security(dir); |
aa8e712c SS |
1763 | return security_transition_sid(&selinux_state, tsec->sid, |
1764 | dsec->sid, tclass, | |
c3c188b2 DH |
1765 | name, _new_isid); |
1766 | } | |
1767 | ||
1768 | return 0; | |
1769 | } | |
1770 | ||
1da177e4 LT |
1771 | /* Check whether a task can create a file. */ |
1772 | static int may_create(struct inode *dir, | |
1773 | struct dentry *dentry, | |
1774 | u16 tclass) | |
1775 | { | |
0c6cfa62 | 1776 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
1da177e4 LT |
1777 | struct inode_security_struct *dsec; |
1778 | struct superblock_security_struct *sbsec; | |
275bb41e | 1779 | u32 sid, newsid; |
2bf49690 | 1780 | struct common_audit_data ad; |
1da177e4 LT |
1781 | int rc; |
1782 | ||
83da53c5 | 1783 | dsec = inode_security(dir); |
1da177e4 LT |
1784 | sbsec = dir->i_sb->s_security; |
1785 | ||
275bb41e | 1786 | sid = tsec->sid; |
275bb41e | 1787 | |
50c205f5 | 1788 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1789 | ad.u.dentry = dentry; |
1da177e4 | 1790 | |
6b6bc620 SS |
1791 | rc = avc_has_perm(&selinux_state, |
1792 | sid, dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
1793 | DIR__ADD_NAME | DIR__SEARCH, |
1794 | &ad); | |
1795 | if (rc) | |
1796 | return rc; | |
1797 | ||
210a2928 YG |
1798 | rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, |
1799 | &newsid); | |
c3c188b2 DH |
1800 | if (rc) |
1801 | return rc; | |
1da177e4 | 1802 | |
6b6bc620 SS |
1803 | rc = avc_has_perm(&selinux_state, |
1804 | sid, newsid, tclass, FILE__CREATE, &ad); | |
1da177e4 LT |
1805 | if (rc) |
1806 | return rc; | |
1807 | ||
6b6bc620 SS |
1808 | return avc_has_perm(&selinux_state, |
1809 | newsid, sbsec->sid, | |
1da177e4 LT |
1810 | SECCLASS_FILESYSTEM, |
1811 | FILESYSTEM__ASSOCIATE, &ad); | |
1812 | } | |
1813 | ||
828dfe1d EP |
1814 | #define MAY_LINK 0 |
1815 | #define MAY_UNLINK 1 | |
1816 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1817 | |
1818 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1819 | static int may_link(struct inode *dir, | |
1820 | struct dentry *dentry, | |
1821 | int kind) | |
1822 | ||
1823 | { | |
1da177e4 | 1824 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 1825 | struct common_audit_data ad; |
275bb41e | 1826 | u32 sid = current_sid(); |
1da177e4 LT |
1827 | u32 av; |
1828 | int rc; | |
1829 | ||
83da53c5 AG |
1830 | dsec = inode_security(dir); |
1831 | isec = backing_inode_security(dentry); | |
1da177e4 | 1832 | |
50c205f5 | 1833 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1834 | ad.u.dentry = dentry; |
1da177e4 LT |
1835 | |
1836 | av = DIR__SEARCH; | |
1837 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
6b6bc620 SS |
1838 | rc = avc_has_perm(&selinux_state, |
1839 | sid, dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
1840 | if (rc) |
1841 | return rc; | |
1842 | ||
1843 | switch (kind) { | |
1844 | case MAY_LINK: | |
1845 | av = FILE__LINK; | |
1846 | break; | |
1847 | case MAY_UNLINK: | |
1848 | av = FILE__UNLINK; | |
1849 | break; | |
1850 | case MAY_RMDIR: | |
1851 | av = DIR__RMDIR; | |
1852 | break; | |
1853 | default: | |
c103a91e | 1854 | pr_warn("SELinux: %s: unrecognized kind %d\n", |
744ba35e | 1855 | __func__, kind); |
1da177e4 LT |
1856 | return 0; |
1857 | } | |
1858 | ||
6b6bc620 SS |
1859 | rc = avc_has_perm(&selinux_state, |
1860 | sid, isec->sid, isec->sclass, av, &ad); | |
1da177e4 LT |
1861 | return rc; |
1862 | } | |
1863 | ||
1864 | static inline int may_rename(struct inode *old_dir, | |
1865 | struct dentry *old_dentry, | |
1866 | struct inode *new_dir, | |
1867 | struct dentry *new_dentry) | |
1868 | { | |
1da177e4 | 1869 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 1870 | struct common_audit_data ad; |
275bb41e | 1871 | u32 sid = current_sid(); |
1da177e4 LT |
1872 | u32 av; |
1873 | int old_is_dir, new_is_dir; | |
1874 | int rc; | |
1875 | ||
83da53c5 AG |
1876 | old_dsec = inode_security(old_dir); |
1877 | old_isec = backing_inode_security(old_dentry); | |
e36cb0b8 | 1878 | old_is_dir = d_is_dir(old_dentry); |
83da53c5 | 1879 | new_dsec = inode_security(new_dir); |
1da177e4 | 1880 | |
50c205f5 | 1881 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 1882 | |
a269434d | 1883 | ad.u.dentry = old_dentry; |
6b6bc620 SS |
1884 | rc = avc_has_perm(&selinux_state, |
1885 | sid, old_dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
1886 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
1887 | if (rc) | |
1888 | return rc; | |
6b6bc620 SS |
1889 | rc = avc_has_perm(&selinux_state, |
1890 | sid, old_isec->sid, | |
1da177e4 LT |
1891 | old_isec->sclass, FILE__RENAME, &ad); |
1892 | if (rc) | |
1893 | return rc; | |
1894 | if (old_is_dir && new_dir != old_dir) { | |
6b6bc620 SS |
1895 | rc = avc_has_perm(&selinux_state, |
1896 | sid, old_isec->sid, | |
1da177e4 LT |
1897 | old_isec->sclass, DIR__REPARENT, &ad); |
1898 | if (rc) | |
1899 | return rc; | |
1900 | } | |
1901 | ||
a269434d | 1902 | ad.u.dentry = new_dentry; |
1da177e4 | 1903 | av = DIR__ADD_NAME | DIR__SEARCH; |
2c616d4d | 1904 | if (d_is_positive(new_dentry)) |
1da177e4 | 1905 | av |= DIR__REMOVE_NAME; |
6b6bc620 SS |
1906 | rc = avc_has_perm(&selinux_state, |
1907 | sid, new_dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
1908 | if (rc) |
1909 | return rc; | |
2c616d4d | 1910 | if (d_is_positive(new_dentry)) { |
83da53c5 | 1911 | new_isec = backing_inode_security(new_dentry); |
e36cb0b8 | 1912 | new_is_dir = d_is_dir(new_dentry); |
6b6bc620 SS |
1913 | rc = avc_has_perm(&selinux_state, |
1914 | sid, new_isec->sid, | |
1da177e4 LT |
1915 | new_isec->sclass, |
1916 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1917 | if (rc) | |
1918 | return rc; | |
1919 | } | |
1920 | ||
1921 | return 0; | |
1922 | } | |
1923 | ||
1924 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 1925 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
1926 | struct super_block *sb, |
1927 | u32 perms, | |
2bf49690 | 1928 | struct common_audit_data *ad) |
1da177e4 | 1929 | { |
1da177e4 | 1930 | struct superblock_security_struct *sbsec; |
88e67f3b | 1931 | u32 sid = cred_sid(cred); |
1da177e4 | 1932 | |
1da177e4 | 1933 | sbsec = sb->s_security; |
6b6bc620 SS |
1934 | return avc_has_perm(&selinux_state, |
1935 | sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); | |
1da177e4 LT |
1936 | } |
1937 | ||
1938 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1939 | static inline u32 file_mask_to_av(int mode, int mask) | |
1940 | { | |
1941 | u32 av = 0; | |
1942 | ||
dba19c60 | 1943 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
1944 | if (mask & MAY_EXEC) |
1945 | av |= FILE__EXECUTE; | |
1946 | if (mask & MAY_READ) | |
1947 | av |= FILE__READ; | |
1948 | ||
1949 | if (mask & MAY_APPEND) | |
1950 | av |= FILE__APPEND; | |
1951 | else if (mask & MAY_WRITE) | |
1952 | av |= FILE__WRITE; | |
1953 | ||
1954 | } else { | |
1955 | if (mask & MAY_EXEC) | |
1956 | av |= DIR__SEARCH; | |
1957 | if (mask & MAY_WRITE) | |
1958 | av |= DIR__WRITE; | |
1959 | if (mask & MAY_READ) | |
1960 | av |= DIR__READ; | |
1961 | } | |
1962 | ||
1963 | return av; | |
1964 | } | |
1965 | ||
8b6a5a37 EP |
1966 | /* Convert a Linux file to an access vector. */ |
1967 | static inline u32 file_to_av(struct file *file) | |
1968 | { | |
1969 | u32 av = 0; | |
1970 | ||
1971 | if (file->f_mode & FMODE_READ) | |
1972 | av |= FILE__READ; | |
1973 | if (file->f_mode & FMODE_WRITE) { | |
1974 | if (file->f_flags & O_APPEND) | |
1975 | av |= FILE__APPEND; | |
1976 | else | |
1977 | av |= FILE__WRITE; | |
1978 | } | |
1979 | if (!av) { | |
1980 | /* | |
1981 | * Special file opened with flags 3 for ioctl-only use. | |
1982 | */ | |
1983 | av = FILE__IOCTL; | |
1984 | } | |
1985 | ||
1986 | return av; | |
1987 | } | |
1988 | ||
b0c636b9 | 1989 | /* |
c76a2f9e | 1990 | * Convert a file to an access vector and include the correct |
b0c636b9 EP |
1991 | * open permission. |
1992 | */ | |
8b6a5a37 | 1993 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 1994 | { |
8b6a5a37 | 1995 | u32 av = file_to_av(file); |
ccb54478 | 1996 | struct inode *inode = file_inode(file); |
b0c636b9 | 1997 | |
aa8e712c SS |
1998 | if (selinux_policycap_openperm() && |
1999 | inode->i_sb->s_magic != SOCKFS_MAGIC) | |
49b7b8de EP |
2000 | av |= FILE__OPEN; |
2001 | ||
b0c636b9 EP |
2002 | return av; |
2003 | } | |
2004 | ||
1da177e4 LT |
2005 | /* Hook functions begin here. */ |
2006 | ||
79af7307 SS |
2007 | static int selinux_binder_set_context_mgr(struct task_struct *mgr) |
2008 | { | |
2009 | u32 mysid = current_sid(); | |
2010 | u32 mgrsid = task_sid(mgr); | |
2011 | ||
6b6bc620 SS |
2012 | return avc_has_perm(&selinux_state, |
2013 | mysid, mgrsid, SECCLASS_BINDER, | |
79af7307 SS |
2014 | BINDER__SET_CONTEXT_MGR, NULL); |
2015 | } | |
2016 | ||
2017 | static int selinux_binder_transaction(struct task_struct *from, | |
2018 | struct task_struct *to) | |
2019 | { | |
2020 | u32 mysid = current_sid(); | |
2021 | u32 fromsid = task_sid(from); | |
2022 | u32 tosid = task_sid(to); | |
2023 | int rc; | |
2024 | ||
2025 | if (mysid != fromsid) { | |
6b6bc620 SS |
2026 | rc = avc_has_perm(&selinux_state, |
2027 | mysid, fromsid, SECCLASS_BINDER, | |
79af7307 SS |
2028 | BINDER__IMPERSONATE, NULL); |
2029 | if (rc) | |
2030 | return rc; | |
2031 | } | |
2032 | ||
6b6bc620 SS |
2033 | return avc_has_perm(&selinux_state, |
2034 | fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, | |
79af7307 SS |
2035 | NULL); |
2036 | } | |
2037 | ||
2038 | static int selinux_binder_transfer_binder(struct task_struct *from, | |
2039 | struct task_struct *to) | |
2040 | { | |
2041 | u32 fromsid = task_sid(from); | |
2042 | u32 tosid = task_sid(to); | |
2043 | ||
6b6bc620 SS |
2044 | return avc_has_perm(&selinux_state, |
2045 | fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, | |
79af7307 SS |
2046 | NULL); |
2047 | } | |
2048 | ||
2049 | static int selinux_binder_transfer_file(struct task_struct *from, | |
2050 | struct task_struct *to, | |
2051 | struct file *file) | |
2052 | { | |
2053 | u32 sid = task_sid(to); | |
bb6c6b02 | 2054 | struct file_security_struct *fsec = selinux_file(file); |
83da53c5 | 2055 | struct dentry *dentry = file->f_path.dentry; |
20cdef8d | 2056 | struct inode_security_struct *isec; |
79af7307 SS |
2057 | struct common_audit_data ad; |
2058 | int rc; | |
2059 | ||
2060 | ad.type = LSM_AUDIT_DATA_PATH; | |
2061 | ad.u.path = file->f_path; | |
2062 | ||
2063 | if (sid != fsec->sid) { | |
6b6bc620 SS |
2064 | rc = avc_has_perm(&selinux_state, |
2065 | sid, fsec->sid, | |
79af7307 SS |
2066 | SECCLASS_FD, |
2067 | FD__USE, | |
2068 | &ad); | |
2069 | if (rc) | |
2070 | return rc; | |
2071 | } | |
2072 | ||
f66e448c CF |
2073 | #ifdef CONFIG_BPF_SYSCALL |
2074 | rc = bpf_fd_pass(file, sid); | |
2075 | if (rc) | |
2076 | return rc; | |
2077 | #endif | |
2078 | ||
83da53c5 | 2079 | if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
79af7307 SS |
2080 | return 0; |
2081 | ||
20cdef8d | 2082 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
2083 | return avc_has_perm(&selinux_state, |
2084 | sid, isec->sid, isec->sclass, file_to_av(file), | |
79af7307 SS |
2085 | &ad); |
2086 | } | |
2087 | ||
9e48858f | 2088 | static int selinux_ptrace_access_check(struct task_struct *child, |
5cd9c58f | 2089 | unsigned int mode) |
1da177e4 | 2090 | { |
be0554c9 SS |
2091 | u32 sid = current_sid(); |
2092 | u32 csid = task_sid(child); | |
2093 | ||
2094 | if (mode & PTRACE_MODE_READ) | |
6b6bc620 SS |
2095 | return avc_has_perm(&selinux_state, |
2096 | sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 | 2097 | |
6b6bc620 SS |
2098 | return avc_has_perm(&selinux_state, |
2099 | sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); | |
5cd9c58f DH |
2100 | } |
2101 | ||
2102 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
2103 | { | |
6b6bc620 SS |
2104 | return avc_has_perm(&selinux_state, |
2105 | task_sid(parent), current_sid(), SECCLASS_PROCESS, | |
be0554c9 | 2106 | PROCESS__PTRACE, NULL); |
1da177e4 LT |
2107 | } |
2108 | ||
2109 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 2110 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 | 2111 | { |
6b6bc620 SS |
2112 | return avc_has_perm(&selinux_state, |
2113 | current_sid(), task_sid(target), SECCLASS_PROCESS, | |
be0554c9 | 2114 | PROCESS__GETCAP, NULL); |
1da177e4 LT |
2115 | } |
2116 | ||
d84f4f99 DH |
2117 | static int selinux_capset(struct cred *new, const struct cred *old, |
2118 | const kernel_cap_t *effective, | |
2119 | const kernel_cap_t *inheritable, | |
2120 | const kernel_cap_t *permitted) | |
1da177e4 | 2121 | { |
6b6bc620 SS |
2122 | return avc_has_perm(&selinux_state, |
2123 | cred_sid(old), cred_sid(new), SECCLASS_PROCESS, | |
be0554c9 | 2124 | PROCESS__SETCAP, NULL); |
1da177e4 LT |
2125 | } |
2126 | ||
5626d3e8 JM |
2127 | /* |
2128 | * (This comment used to live with the selinux_task_setuid hook, | |
2129 | * which was removed). | |
2130 | * | |
2131 | * Since setuid only affects the current process, and since the SELinux | |
2132 | * controls are not based on the Linux identity attributes, SELinux does not | |
2133 | * need to control this operation. However, SELinux does control the use of | |
2134 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
2135 | */ | |
2136 | ||
6a9de491 | 2137 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
c1a85a00 | 2138 | int cap, unsigned int opts) |
1da177e4 | 2139 | { |
c1a85a00 | 2140 | return cred_has_capability(cred, cap, opts, ns == &init_user_ns); |
1da177e4 LT |
2141 | } |
2142 | ||
1da177e4 LT |
2143 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
2144 | { | |
88e67f3b | 2145 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2146 | int rc = 0; |
2147 | ||
2148 | if (!sb) | |
2149 | return 0; | |
2150 | ||
2151 | switch (cmds) { | |
828dfe1d EP |
2152 | case Q_SYNC: |
2153 | case Q_QUOTAON: | |
2154 | case Q_QUOTAOFF: | |
2155 | case Q_SETINFO: | |
2156 | case Q_SETQUOTA: | |
e4cfa05e RH |
2157 | case Q_XQUOTAOFF: |
2158 | case Q_XQUOTAON: | |
2159 | case Q_XSETQLIM: | |
88e67f3b | 2160 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
2161 | break; |
2162 | case Q_GETFMT: | |
2163 | case Q_GETINFO: | |
2164 | case Q_GETQUOTA: | |
e4cfa05e RH |
2165 | case Q_XGETQUOTA: |
2166 | case Q_XGETQSTAT: | |
2167 | case Q_XGETQSTATV: | |
2168 | case Q_XGETNEXTQUOTA: | |
88e67f3b | 2169 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
2170 | break; |
2171 | default: | |
2172 | rc = 0; /* let the kernel handle invalid cmds */ | |
2173 | break; | |
1da177e4 LT |
2174 | } |
2175 | return rc; | |
2176 | } | |
2177 | ||
2178 | static int selinux_quota_on(struct dentry *dentry) | |
2179 | { | |
88e67f3b DH |
2180 | const struct cred *cred = current_cred(); |
2181 | ||
2875fa00 | 2182 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
2183 | } |
2184 | ||
12b3052c | 2185 | static int selinux_syslog(int type) |
1da177e4 | 2186 | { |
1da177e4 | 2187 | switch (type) { |
d78ca3cd KC |
2188 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2189 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
6b6bc620 SS |
2190 | return avc_has_perm(&selinux_state, |
2191 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2192 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); |
d78ca3cd KC |
2193 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2194 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2195 | /* Set level of messages printed to console */ | |
2196 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
6b6bc620 SS |
2197 | return avc_has_perm(&selinux_state, |
2198 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 SS |
2199 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, |
2200 | NULL); | |
1da177e4 | 2201 | } |
be0554c9 | 2202 | /* All other syslog types */ |
6b6bc620 SS |
2203 | return avc_has_perm(&selinux_state, |
2204 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2205 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); |
1da177e4 LT |
2206 | } |
2207 | ||
2208 | /* | |
2209 | * Check that a process has enough memory to allocate a new virtual | |
2210 | * mapping. 0 means there is enough memory for the allocation to | |
2211 | * succeed and -ENOMEM implies there is not. | |
2212 | * | |
1da177e4 LT |
2213 | * Do not audit the selinux permission check, as this is applied to all |
2214 | * processes that allocate mappings. | |
2215 | */ | |
34b4e4aa | 2216 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2217 | { |
2218 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2219 | |
b1d9e6b0 | 2220 | rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, |
c1a85a00 | 2221 | CAP_OPT_NOAUDIT, true); |
1da177e4 LT |
2222 | if (rc == 0) |
2223 | cap_sys_admin = 1; | |
2224 | ||
b1d9e6b0 | 2225 | return cap_sys_admin; |
1da177e4 LT |
2226 | } |
2227 | ||
2228 | /* binprm security operations */ | |
2229 | ||
be0554c9 | 2230 | static u32 ptrace_parent_sid(void) |
0c6181cb PM |
2231 | { |
2232 | u32 sid = 0; | |
2233 | struct task_struct *tracer; | |
2234 | ||
2235 | rcu_read_lock(); | |
be0554c9 | 2236 | tracer = ptrace_parent(current); |
0c6181cb PM |
2237 | if (tracer) |
2238 | sid = task_sid(tracer); | |
2239 | rcu_read_unlock(); | |
2240 | ||
2241 | return sid; | |
2242 | } | |
2243 | ||
7b0d0b40 SS |
2244 | static int check_nnp_nosuid(const struct linux_binprm *bprm, |
2245 | const struct task_security_struct *old_tsec, | |
2246 | const struct task_security_struct *new_tsec) | |
2247 | { | |
2248 | int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); | |
104c1332 | 2249 | int nosuid = path_nosuid(&bprm->file->f_path); |
7b0d0b40 | 2250 | int rc; |
af63f419 | 2251 | u32 av; |
7b0d0b40 SS |
2252 | |
2253 | if (!nnp && !nosuid) | |
2254 | return 0; /* neither NNP nor nosuid */ | |
2255 | ||
2256 | if (new_tsec->sid == old_tsec->sid) | |
2257 | return 0; /* No change in credentials */ | |
2258 | ||
2259 | /* | |
af63f419 SS |
2260 | * If the policy enables the nnp_nosuid_transition policy capability, |
2261 | * then we permit transitions under NNP or nosuid if the | |
2262 | * policy allows the corresponding permission between | |
2263 | * the old and new contexts. | |
7b0d0b40 | 2264 | */ |
aa8e712c | 2265 | if (selinux_policycap_nnp_nosuid_transition()) { |
af63f419 | 2266 | av = 0; |
7b0d0b40 | 2267 | if (nnp) |
af63f419 SS |
2268 | av |= PROCESS2__NNP_TRANSITION; |
2269 | if (nosuid) | |
2270 | av |= PROCESS2__NOSUID_TRANSITION; | |
6b6bc620 SS |
2271 | rc = avc_has_perm(&selinux_state, |
2272 | old_tsec->sid, new_tsec->sid, | |
af63f419 SS |
2273 | SECCLASS_PROCESS2, av, NULL); |
2274 | if (!rc) | |
2275 | return 0; | |
7b0d0b40 | 2276 | } |
af63f419 SS |
2277 | |
2278 | /* | |
2279 | * We also permit NNP or nosuid transitions to bounded SIDs, | |
2280 | * i.e. SIDs that are guaranteed to only be allowed a subset | |
2281 | * of the permissions of the current SID. | |
2282 | */ | |
aa8e712c SS |
2283 | rc = security_bounded_transition(&selinux_state, old_tsec->sid, |
2284 | new_tsec->sid); | |
af63f419 SS |
2285 | if (!rc) |
2286 | return 0; | |
2287 | ||
2288 | /* | |
2289 | * On failure, preserve the errno values for NNP vs nosuid. | |
2290 | * NNP: Operation not permitted for caller. | |
2291 | * nosuid: Permission denied to file. | |
2292 | */ | |
2293 | if (nnp) | |
2294 | return -EPERM; | |
2295 | return -EACCES; | |
7b0d0b40 SS |
2296 | } |
2297 | ||
b8bff599 | 2298 | static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) |
1da177e4 | 2299 | { |
a6f76f23 DH |
2300 | const struct task_security_struct *old_tsec; |
2301 | struct task_security_struct *new_tsec; | |
1da177e4 | 2302 | struct inode_security_struct *isec; |
2bf49690 | 2303 | struct common_audit_data ad; |
496ad9aa | 2304 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2305 | int rc; |
2306 | ||
a6f76f23 DH |
2307 | /* SELinux context only depends on initial program or script and not |
2308 | * the script interpreter */ | |
1da177e4 | 2309 | |
0c6cfa62 CS |
2310 | old_tsec = selinux_cred(current_cred()); |
2311 | new_tsec = selinux_cred(bprm->cred); | |
83da53c5 | 2312 | isec = inode_security(inode); |
1da177e4 LT |
2313 | |
2314 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2315 | new_tsec->sid = old_tsec->sid; |
2316 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2317 | |
28eba5bf | 2318 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2319 | new_tsec->create_sid = 0; |
2320 | new_tsec->keycreate_sid = 0; | |
2321 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2322 | |
a6f76f23 DH |
2323 | if (old_tsec->exec_sid) { |
2324 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2325 | /* Reset exec SID on execve. */ |
a6f76f23 | 2326 | new_tsec->exec_sid = 0; |
259e5e6c | 2327 | |
7b0d0b40 SS |
2328 | /* Fail on NNP or nosuid if not an allowed transition. */ |
2329 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2330 | if (rc) | |
2331 | return rc; | |
1da177e4 LT |
2332 | } else { |
2333 | /* Check for a default transition on this program. */ | |
aa8e712c SS |
2334 | rc = security_transition_sid(&selinux_state, old_tsec->sid, |
2335 | isec->sid, SECCLASS_PROCESS, NULL, | |
652bb9b0 | 2336 | &new_tsec->sid); |
1da177e4 LT |
2337 | if (rc) |
2338 | return rc; | |
7b0d0b40 SS |
2339 | |
2340 | /* | |
2341 | * Fallback to old SID on NNP or nosuid if not an allowed | |
2342 | * transition. | |
2343 | */ | |
2344 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2345 | if (rc) | |
2346 | new_tsec->sid = old_tsec->sid; | |
1da177e4 LT |
2347 | } |
2348 | ||
43af5de7 VG |
2349 | ad.type = LSM_AUDIT_DATA_FILE; |
2350 | ad.u.file = bprm->file; | |
1da177e4 | 2351 | |
a6f76f23 | 2352 | if (new_tsec->sid == old_tsec->sid) { |
6b6bc620 SS |
2353 | rc = avc_has_perm(&selinux_state, |
2354 | old_tsec->sid, isec->sid, | |
1da177e4 LT |
2355 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2356 | if (rc) | |
2357 | return rc; | |
2358 | } else { | |
2359 | /* Check permissions for the transition. */ | |
6b6bc620 SS |
2360 | rc = avc_has_perm(&selinux_state, |
2361 | old_tsec->sid, new_tsec->sid, | |
1da177e4 LT |
2362 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2363 | if (rc) | |
2364 | return rc; | |
2365 | ||
6b6bc620 SS |
2366 | rc = avc_has_perm(&selinux_state, |
2367 | new_tsec->sid, isec->sid, | |
1da177e4 LT |
2368 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2369 | if (rc) | |
2370 | return rc; | |
2371 | ||
a6f76f23 DH |
2372 | /* Check for shared state */ |
2373 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
6b6bc620 SS |
2374 | rc = avc_has_perm(&selinux_state, |
2375 | old_tsec->sid, new_tsec->sid, | |
a6f76f23 DH |
2376 | SECCLASS_PROCESS, PROCESS__SHARE, |
2377 | NULL); | |
2378 | if (rc) | |
2379 | return -EPERM; | |
2380 | } | |
2381 | ||
2382 | /* Make sure that anyone attempting to ptrace over a task that | |
2383 | * changes its SID has the appropriate permit */ | |
9227dd2a | 2384 | if (bprm->unsafe & LSM_UNSAFE_PTRACE) { |
be0554c9 | 2385 | u32 ptsid = ptrace_parent_sid(); |
a6f76f23 | 2386 | if (ptsid != 0) { |
6b6bc620 SS |
2387 | rc = avc_has_perm(&selinux_state, |
2388 | ptsid, new_tsec->sid, | |
a6f76f23 DH |
2389 | SECCLASS_PROCESS, |
2390 | PROCESS__PTRACE, NULL); | |
2391 | if (rc) | |
2392 | return -EPERM; | |
2393 | } | |
2394 | } | |
1da177e4 | 2395 | |
a6f76f23 DH |
2396 | /* Clear any possibly unsafe personality bits on exec: */ |
2397 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
275bb41e | 2398 | |
1da177e4 LT |
2399 | /* Enable secure mode for SIDs transitions unless |
2400 | the noatsecure permission is granted between | |
2401 | the two SIDs, i.e. ahp returns 0. */ | |
6b6bc620 SS |
2402 | rc = avc_has_perm(&selinux_state, |
2403 | old_tsec->sid, new_tsec->sid, | |
62874c3a KC |
2404 | SECCLASS_PROCESS, PROCESS__NOATSECURE, |
2405 | NULL); | |
2406 | bprm->secureexec |= !!rc; | |
1da177e4 LT |
2407 | } |
2408 | ||
62874c3a | 2409 | return 0; |
1da177e4 LT |
2410 | } |
2411 | ||
c3c073f8 AV |
2412 | static int match_file(const void *p, struct file *file, unsigned fd) |
2413 | { | |
2414 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2415 | } | |
2416 | ||
1da177e4 | 2417 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2418 | static inline void flush_unauthorized_files(const struct cred *cred, |
2419 | struct files_struct *files) | |
1da177e4 | 2420 | { |
1da177e4 | 2421 | struct file *file, *devnull = NULL; |
b20c8122 | 2422 | struct tty_struct *tty; |
24ec839c | 2423 | int drop_tty = 0; |
c3c073f8 | 2424 | unsigned n; |
1da177e4 | 2425 | |
24ec839c | 2426 | tty = get_current_tty(); |
1da177e4 | 2427 | if (tty) { |
4a510969 | 2428 | spin_lock(&tty->files_lock); |
37dd0bd0 | 2429 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2430 | struct tty_file_private *file_priv; |
37dd0bd0 | 2431 | |
1da177e4 | 2432 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2433 | Use file_path_has_perm on the tty path directly |
2434 | rather than using file_has_perm, as this particular | |
2435 | open file may belong to another process and we are | |
2436 | only interested in the inode-based check here. */ | |
d996b62a NP |
2437 | file_priv = list_first_entry(&tty->tty_files, |
2438 | struct tty_file_private, list); | |
2439 | file = file_priv->file; | |
13f8e981 | 2440 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2441 | drop_tty = 1; |
1da177e4 | 2442 | } |
4a510969 | 2443 | spin_unlock(&tty->files_lock); |
452a00d2 | 2444 | tty_kref_put(tty); |
1da177e4 | 2445 | } |
98a27ba4 EB |
2446 | /* Reset controlling tty. */ |
2447 | if (drop_tty) | |
2448 | no_tty(); | |
1da177e4 LT |
2449 | |
2450 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2451 | n = iterate_fd(files, 0, match_file, cred); |
2452 | if (!n) /* none found? */ | |
2453 | return; | |
1da177e4 | 2454 | |
c3c073f8 | 2455 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2456 | if (IS_ERR(devnull)) |
2457 | devnull = NULL; | |
2458 | /* replace all the matching ones with this */ | |
2459 | do { | |
2460 | replace_fd(n - 1, devnull, 0); | |
2461 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2462 | if (devnull) | |
c3c073f8 | 2463 | fput(devnull); |
1da177e4 LT |
2464 | } |
2465 | ||
a6f76f23 DH |
2466 | /* |
2467 | * Prepare a process for imminent new credential changes due to exec | |
2468 | */ | |
2469 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2470 | { |
a6f76f23 DH |
2471 | struct task_security_struct *new_tsec; |
2472 | struct rlimit *rlim, *initrlim; | |
2473 | int rc, i; | |
d84f4f99 | 2474 | |
0c6cfa62 | 2475 | new_tsec = selinux_cred(bprm->cred); |
a6f76f23 DH |
2476 | if (new_tsec->sid == new_tsec->osid) |
2477 | return; | |
1da177e4 | 2478 | |
a6f76f23 DH |
2479 | /* Close files for which the new task SID is not authorized. */ |
2480 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2481 | |
a6f76f23 DH |
2482 | /* Always clear parent death signal on SID transitions. */ |
2483 | current->pdeath_signal = 0; | |
0356357c | 2484 | |
a6f76f23 DH |
2485 | /* Check whether the new SID can inherit resource limits from the old |
2486 | * SID. If not, reset all soft limits to the lower of the current | |
2487 | * task's hard limit and the init task's soft limit. | |
2488 | * | |
2489 | * Note that the setting of hard limits (even to lower them) can be | |
2490 | * controlled by the setrlimit check. The inclusion of the init task's | |
2491 | * soft limit into the computation is to avoid resetting soft limits | |
2492 | * higher than the default soft limit for cases where the default is | |
2493 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2494 | */ | |
6b6bc620 SS |
2495 | rc = avc_has_perm(&selinux_state, |
2496 | new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
a6f76f23 DH |
2497 | PROCESS__RLIMITINH, NULL); |
2498 | if (rc) { | |
eb2d55a3 ON |
2499 | /* protect against do_prlimit() */ |
2500 | task_lock(current); | |
a6f76f23 DH |
2501 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2502 | rlim = current->signal->rlim + i; | |
2503 | initrlim = init_task.signal->rlim + i; | |
2504 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2505 | } |
eb2d55a3 | 2506 | task_unlock(current); |
baa73d9e NP |
2507 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) |
2508 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2509 | } |
2510 | } | |
2511 | ||
2512 | /* | |
a6f76f23 DH |
2513 | * Clean up the process immediately after the installation of new credentials |
2514 | * due to exec | |
1da177e4 | 2515 | */ |
a6f76f23 | 2516 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2517 | { |
0c6cfa62 | 2518 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
a6f76f23 | 2519 | u32 osid, sid; |
ddbc7d06 | 2520 | int rc; |
1da177e4 | 2521 | |
a6f76f23 DH |
2522 | osid = tsec->osid; |
2523 | sid = tsec->sid; | |
2524 | ||
2525 | if (sid == osid) | |
1da177e4 LT |
2526 | return; |
2527 | ||
a6f76f23 DH |
2528 | /* Check whether the new SID can inherit signal state from the old SID. |
2529 | * If not, clear itimers to avoid subsequent signal generation and | |
2530 | * flush and unblock signals. | |
2531 | * | |
2532 | * This must occur _after_ the task SID has been updated so that any | |
2533 | * kill done after the flush will be checked against the new SID. | |
2534 | */ | |
6b6bc620 SS |
2535 | rc = avc_has_perm(&selinux_state, |
2536 | osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 | 2537 | if (rc) { |
ddbc7d06 AB |
2538 | clear_itimer(); |
2539 | ||
1da177e4 | 2540 | spin_lock_irq(¤t->sighand->siglock); |
9e7c8f8c ON |
2541 | if (!fatal_signal_pending(current)) { |
2542 | flush_sigqueue(¤t->pending); | |
2543 | flush_sigqueue(¤t->signal->shared_pending); | |
3bcac026 DH |
2544 | flush_signal_handlers(current, 1); |
2545 | sigemptyset(¤t->blocked); | |
9e7c8f8c | 2546 | recalc_sigpending(); |
3bcac026 | 2547 | } |
1da177e4 LT |
2548 | spin_unlock_irq(¤t->sighand->siglock); |
2549 | } | |
2550 | ||
a6f76f23 DH |
2551 | /* Wake up the parent if it is waiting so that it can recheck |
2552 | * wait permission to the new task SID. */ | |
ecd6de3c | 2553 | read_lock(&tasklist_lock); |
0b7570e7 | 2554 | __wake_up_parent(current, current->real_parent); |
ecd6de3c | 2555 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2556 | } |
2557 | ||
2558 | /* superblock security operations */ | |
2559 | ||
2560 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2561 | { | |
cb89e246 PM |
2562 | struct superblock_security_struct *sbsec; |
2563 | ||
2564 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); | |
2565 | if (!sbsec) | |
2566 | return -ENOMEM; | |
2567 | ||
2568 | mutex_init(&sbsec->lock); | |
2569 | INIT_LIST_HEAD(&sbsec->isec_head); | |
2570 | spin_lock_init(&sbsec->isec_lock); | |
cb89e246 PM |
2571 | sbsec->sid = SECINITSID_UNLABELED; |
2572 | sbsec->def_sid = SECINITSID_FILE; | |
2573 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; | |
2574 | sb->s_security = sbsec; | |
2575 | ||
2576 | return 0; | |
1da177e4 LT |
2577 | } |
2578 | ||
2579 | static void selinux_sb_free_security(struct super_block *sb) | |
2580 | { | |
2581 | superblock_free_security(sb); | |
2582 | } | |
2583 | ||
99dbbb59 | 2584 | static inline int opt_len(const char *s) |
1da177e4 | 2585 | { |
99dbbb59 AV |
2586 | bool open_quote = false; |
2587 | int len; | |
2588 | char c; | |
1da177e4 | 2589 | |
99dbbb59 AV |
2590 | for (len = 0; (c = s[len]) != '\0'; len++) { |
2591 | if (c == '"') | |
2592 | open_quote = !open_quote; | |
2593 | if (c == ',' && !open_quote) | |
2594 | break; | |
3528a953 | 2595 | } |
99dbbb59 | 2596 | return len; |
3528a953 CO |
2597 | } |
2598 | ||
99dbbb59 | 2599 | static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) |
1da177e4 | 2600 | { |
99dbbb59 AV |
2601 | char *from = options; |
2602 | char *to = options; | |
2603 | bool first = true; | |
fec63753 | 2604 | int rc; |
1da177e4 | 2605 | |
99dbbb59 AV |
2606 | while (1) { |
2607 | int len = opt_len(from); | |
fec63753 | 2608 | int token; |
99dbbb59 | 2609 | char *arg = NULL; |
1da177e4 | 2610 | |
99dbbb59 | 2611 | token = match_opt_prefix(from, len, &arg); |
1da177e4 | 2612 | |
99dbbb59 AV |
2613 | if (token != Opt_error) { |
2614 | char *p, *q; | |
1da177e4 | 2615 | |
99dbbb59 AV |
2616 | /* strip quotes */ |
2617 | if (arg) { | |
2618 | for (p = q = arg; p < from + len; p++) { | |
2619 | char c = *p; | |
2620 | if (c != '"') | |
2621 | *q++ = c; | |
2622 | } | |
2623 | arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); | |
fec63753 GZ |
2624 | if (!arg) { |
2625 | rc = -ENOMEM; | |
2626 | goto free_opt; | |
2627 | } | |
99dbbb59 AV |
2628 | } |
2629 | rc = selinux_add_opt(token, arg, mnt_opts); | |
2630 | if (unlikely(rc)) { | |
2631 | kfree(arg); | |
fec63753 | 2632 | goto free_opt; |
99dbbb59 AV |
2633 | } |
2634 | } else { | |
2635 | if (!first) { // copy with preceding comma | |
2636 | from--; | |
2637 | len++; | |
2638 | } | |
2639 | if (to != from) | |
2640 | memmove(to, from, len); | |
2641 | to += len; | |
2642 | first = false; | |
1da177e4 | 2643 | } |
99dbbb59 AV |
2644 | if (!from[len]) |
2645 | break; | |
2646 | from += len + 1; | |
2647 | } | |
2648 | *to = '\0'; | |
2649 | return 0; | |
fec63753 GZ |
2650 | |
2651 | free_opt: | |
2652 | if (*mnt_opts) { | |
2653 | selinux_free_mnt_opts(*mnt_opts); | |
2654 | *mnt_opts = NULL; | |
2655 | } | |
2656 | return rc; | |
1da177e4 LT |
2657 | } |
2658 | ||
204cc0cc | 2659 | static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) |
026eb167 | 2660 | { |
bd323655 | 2661 | struct selinux_mnt_opts *opts = mnt_opts; |
026eb167 | 2662 | struct superblock_security_struct *sbsec = sb->s_security; |
bd323655 AV |
2663 | u32 sid; |
2664 | int rc; | |
026eb167 EP |
2665 | |
2666 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2667 | return 0; | |
2668 | ||
204cc0cc | 2669 | if (!opts) |
026eb167 EP |
2670 | return 0; |
2671 | ||
bd323655 AV |
2672 | if (opts->fscontext) { |
2673 | rc = parse_sid(sb, opts->fscontext, &sid); | |
2674 | if (rc) | |
c039bc3c | 2675 | return rc; |
bd323655 AV |
2676 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) |
2677 | goto out_bad_option; | |
026eb167 | 2678 | } |
bd323655 AV |
2679 | if (opts->context) { |
2680 | rc = parse_sid(sb, opts->context, &sid); | |
2681 | if (rc) | |
2682 | return rc; | |
2683 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2684 | goto out_bad_option; | |
2685 | } | |
2686 | if (opts->rootcontext) { | |
2687 | struct inode_security_struct *root_isec; | |
2688 | root_isec = backing_inode_security(sb->s_root); | |
2689 | rc = parse_sid(sb, opts->rootcontext, &sid); | |
2690 | if (rc) | |
2691 | return rc; | |
2692 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2693 | goto out_bad_option; | |
2694 | } | |
2695 | if (opts->defcontext) { | |
2696 | rc = parse_sid(sb, opts->defcontext, &sid); | |
2697 | if (rc) | |
2698 | return rc; | |
2699 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2700 | goto out_bad_option; | |
026eb167 | 2701 | } |
c039bc3c | 2702 | return 0; |
026eb167 | 2703 | |
026eb167 | 2704 | out_bad_option: |
c103a91e | 2705 | pr_warn("SELinux: unable to change security options " |
29b1deb2 LT |
2706 | "during remount (dev %s, type=%s)\n", sb->s_id, |
2707 | sb->s_type->name); | |
c039bc3c | 2708 | return -EINVAL; |
026eb167 EP |
2709 | } |
2710 | ||
a10d7c22 | 2711 | static int selinux_sb_kern_mount(struct super_block *sb) |
1da177e4 | 2712 | { |
88e67f3b | 2713 | const struct cred *cred = current_cred(); |
2bf49690 | 2714 | struct common_audit_data ad; |
74192246 | 2715 | |
50c205f5 | 2716 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2717 | ad.u.dentry = sb->s_root; |
88e67f3b | 2718 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2719 | } |
2720 | ||
726c3342 | 2721 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2722 | { |
88e67f3b | 2723 | const struct cred *cred = current_cred(); |
2bf49690 | 2724 | struct common_audit_data ad; |
1da177e4 | 2725 | |
50c205f5 | 2726 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2727 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2728 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2729 | } |
2730 | ||
808d4e3c | 2731 | static int selinux_mount(const char *dev_name, |
8a04c43b | 2732 | const struct path *path, |
808d4e3c | 2733 | const char *type, |
828dfe1d EP |
2734 | unsigned long flags, |
2735 | void *data) | |
1da177e4 | 2736 | { |
88e67f3b | 2737 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2738 | |
2739 | if (flags & MS_REMOUNT) | |
d8c9584e | 2740 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2741 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2742 | else |
2875fa00 | 2743 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2744 | } |
2745 | ||
98aa0034 SS |
2746 | static int selinux_move_mount(const struct path *from_path, |
2747 | const struct path *to_path) | |
2748 | { | |
2749 | const struct cred *cred = current_cred(); | |
2750 | ||
2751 | return path_has_perm(cred, to_path, FILE__MOUNTON); | |
2752 | } | |
2753 | ||
1da177e4 LT |
2754 | static int selinux_umount(struct vfsmount *mnt, int flags) |
2755 | { | |
88e67f3b | 2756 | const struct cred *cred = current_cred(); |
1da177e4 | 2757 | |
88e67f3b | 2758 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2759 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2760 | } |
2761 | ||
0b52075e AV |
2762 | static int selinux_fs_context_dup(struct fs_context *fc, |
2763 | struct fs_context *src_fc) | |
2764 | { | |
2765 | const struct selinux_mnt_opts *src = src_fc->security; | |
2766 | struct selinux_mnt_opts *opts; | |
2767 | ||
2768 | if (!src) | |
2769 | return 0; | |
2770 | ||
2771 | fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); | |
2772 | if (!fc->security) | |
2773 | return -ENOMEM; | |
2774 | ||
2775 | opts = fc->security; | |
2776 | ||
2777 | if (src->fscontext) { | |
2778 | opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL); | |
2779 | if (!opts->fscontext) | |
2780 | return -ENOMEM; | |
2781 | } | |
2782 | if (src->context) { | |
2783 | opts->context = kstrdup(src->context, GFP_KERNEL); | |
2784 | if (!opts->context) | |
2785 | return -ENOMEM; | |
2786 | } | |
2787 | if (src->rootcontext) { | |
2788 | opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL); | |
2789 | if (!opts->rootcontext) | |
2790 | return -ENOMEM; | |
2791 | } | |
2792 | if (src->defcontext) { | |
2793 | opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL); | |
2794 | if (!opts->defcontext) | |
2795 | return -ENOMEM; | |
2796 | } | |
2797 | return 0; | |
2798 | } | |
2799 | ||
d7167b14 | 2800 | static const struct fs_parameter_spec selinux_fs_parameters[] = { |
442155c1 DH |
2801 | fsparam_string(CONTEXT_STR, Opt_context), |
2802 | fsparam_string(DEFCONTEXT_STR, Opt_defcontext), | |
2803 | fsparam_string(FSCONTEXT_STR, Opt_fscontext), | |
2804 | fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), | |
2805 | fsparam_flag (SECLABEL_STR, Opt_seclabel), | |
2806 | {} | |
2807 | }; | |
2808 | ||
442155c1 DH |
2809 | static int selinux_fs_context_parse_param(struct fs_context *fc, |
2810 | struct fs_parameter *param) | |
2811 | { | |
2812 | struct fs_parse_result result; | |
2813 | int opt, rc; | |
2814 | ||
d7167b14 | 2815 | opt = fs_parse(fc, selinux_fs_parameters, param, &result); |
442155c1 DH |
2816 | if (opt < 0) |
2817 | return opt; | |
2818 | ||
2819 | rc = selinux_add_opt(opt, param->string, &fc->security); | |
2820 | if (!rc) { | |
2821 | param->string = NULL; | |
2822 | rc = 1; | |
2823 | } | |
2824 | return rc; | |
2825 | } | |
2826 | ||
1da177e4 LT |
2827 | /* inode security operations */ |
2828 | ||
2829 | static int selinux_inode_alloc_security(struct inode *inode) | |
2830 | { | |
cb89e246 PM |
2831 | struct inode_security_struct *isec = selinux_inode(inode); |
2832 | u32 sid = current_sid(); | |
2833 | ||
2834 | spin_lock_init(&isec->lock); | |
2835 | INIT_LIST_HEAD(&isec->list); | |
2836 | isec->inode = inode; | |
2837 | isec->sid = SECINITSID_UNLABELED; | |
2838 | isec->sclass = SECCLASS_FILE; | |
2839 | isec->task_sid = sid; | |
2840 | isec->initialized = LABEL_INVALID; | |
2841 | ||
2842 | return 0; | |
1da177e4 LT |
2843 | } |
2844 | ||
2845 | static void selinux_inode_free_security(struct inode *inode) | |
2846 | { | |
2847 | inode_free_security(inode); | |
2848 | } | |
2849 | ||
d47be3df | 2850 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
4f3ccd76 | 2851 | const struct qstr *name, void **ctx, |
d47be3df DQ |
2852 | u32 *ctxlen) |
2853 | { | |
d47be3df DQ |
2854 | u32 newsid; |
2855 | int rc; | |
2856 | ||
0c6cfa62 | 2857 | rc = selinux_determine_inode_label(selinux_cred(current_cred()), |
c957f6df | 2858 | d_inode(dentry->d_parent), name, |
c3c188b2 DH |
2859 | inode_mode_to_security_class(mode), |
2860 | &newsid); | |
2861 | if (rc) | |
2862 | return rc; | |
d47be3df | 2863 | |
aa8e712c SS |
2864 | return security_sid_to_context(&selinux_state, newsid, (char **)ctx, |
2865 | ctxlen); | |
d47be3df DQ |
2866 | } |
2867 | ||
a518b0a5 VG |
2868 | static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, |
2869 | struct qstr *name, | |
2870 | const struct cred *old, | |
2871 | struct cred *new) | |
2872 | { | |
2873 | u32 newsid; | |
2874 | int rc; | |
2875 | struct task_security_struct *tsec; | |
2876 | ||
0c6cfa62 | 2877 | rc = selinux_determine_inode_label(selinux_cred(old), |
a518b0a5 VG |
2878 | d_inode(dentry->d_parent), name, |
2879 | inode_mode_to_security_class(mode), | |
2880 | &newsid); | |
2881 | if (rc) | |
2882 | return rc; | |
2883 | ||
0c6cfa62 | 2884 | tsec = selinux_cred(new); |
a518b0a5 VG |
2885 | tsec->create_sid = newsid; |
2886 | return 0; | |
2887 | } | |
2888 | ||
5e41ff9e | 2889 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
2890 | const struct qstr *qstr, |
2891 | const char **name, | |
2a7dba39 | 2892 | void **value, size_t *len) |
5e41ff9e | 2893 | { |
0c6cfa62 | 2894 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
5e41ff9e | 2895 | struct superblock_security_struct *sbsec; |
c0d4f464 | 2896 | u32 newsid, clen; |
5e41ff9e | 2897 | int rc; |
9548906b | 2898 | char *context; |
5e41ff9e | 2899 | |
5e41ff9e | 2900 | sbsec = dir->i_sb->s_security; |
5e41ff9e | 2901 | |
275bb41e DH |
2902 | newsid = tsec->create_sid; |
2903 | ||
210a2928 | 2904 | rc = selinux_determine_inode_label(tsec, dir, qstr, |
c3c188b2 DH |
2905 | inode_mode_to_security_class(inode->i_mode), |
2906 | &newsid); | |
2907 | if (rc) | |
2908 | return rc; | |
5e41ff9e | 2909 | |
296fddf7 | 2910 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 2911 | if (sbsec->flags & SE_SBINITIALIZED) { |
80788c22 | 2912 | struct inode_security_struct *isec = selinux_inode(inode); |
296fddf7 EP |
2913 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
2914 | isec->sid = newsid; | |
6f3be9f5 | 2915 | isec->initialized = LABEL_INITIALIZED; |
296fddf7 | 2916 | } |
5e41ff9e | 2917 | |
65cddd50 OM |
2918 | if (!selinux_initialized(&selinux_state) || |
2919 | !(sbsec->flags & SBLABEL_MNT)) | |
25a74f3b SS |
2920 | return -EOPNOTSUPP; |
2921 | ||
9548906b TH |
2922 | if (name) |
2923 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 2924 | |
570bc1c2 | 2925 | if (value && len) { |
aa8e712c SS |
2926 | rc = security_sid_to_context_force(&selinux_state, newsid, |
2927 | &context, &clen); | |
9548906b | 2928 | if (rc) |
570bc1c2 | 2929 | return rc; |
570bc1c2 SS |
2930 | *value = context; |
2931 | *len = clen; | |
5e41ff9e | 2932 | } |
5e41ff9e | 2933 | |
5e41ff9e SS |
2934 | return 0; |
2935 | } | |
2936 | ||
4acdaf27 | 2937 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
2938 | { |
2939 | return may_create(dir, dentry, SECCLASS_FILE); | |
2940 | } | |
2941 | ||
1da177e4 LT |
2942 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2943 | { | |
1da177e4 LT |
2944 | return may_link(dir, old_dentry, MAY_LINK); |
2945 | } | |
2946 | ||
1da177e4 LT |
2947 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2948 | { | |
1da177e4 LT |
2949 | return may_link(dir, dentry, MAY_UNLINK); |
2950 | } | |
2951 | ||
2952 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2953 | { | |
2954 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2955 | } | |
2956 | ||
18bb1db3 | 2957 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
2958 | { |
2959 | return may_create(dir, dentry, SECCLASS_DIR); | |
2960 | } | |
2961 | ||
1da177e4 LT |
2962 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2963 | { | |
2964 | return may_link(dir, dentry, MAY_RMDIR); | |
2965 | } | |
2966 | ||
1a67aafb | 2967 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 2968 | { |
1da177e4 LT |
2969 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
2970 | } | |
2971 | ||
1da177e4 | 2972 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 2973 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
2974 | { |
2975 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2976 | } | |
2977 | ||
1da177e4 LT |
2978 | static int selinux_inode_readlink(struct dentry *dentry) |
2979 | { | |
88e67f3b DH |
2980 | const struct cred *cred = current_cred(); |
2981 | ||
2875fa00 | 2982 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
2983 | } |
2984 | ||
bda0be7a N |
2985 | static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, |
2986 | bool rcu) | |
1da177e4 | 2987 | { |
88e67f3b | 2988 | const struct cred *cred = current_cred(); |
bda0be7a N |
2989 | struct common_audit_data ad; |
2990 | struct inode_security_struct *isec; | |
2991 | u32 sid; | |
1da177e4 | 2992 | |
bda0be7a N |
2993 | validate_creds(cred); |
2994 | ||
2995 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
2996 | ad.u.dentry = dentry; | |
2997 | sid = cred_sid(cred); | |
5d226df4 AG |
2998 | isec = inode_security_rcu(inode, rcu); |
2999 | if (IS_ERR(isec)) | |
3000 | return PTR_ERR(isec); | |
bda0be7a | 3001 | |
1a37079c SS |
3002 | return avc_has_perm_flags(&selinux_state, |
3003 | sid, isec->sid, isec->sclass, FILE__READ, &ad, | |
3004 | rcu ? MAY_NOT_BLOCK : 0); | |
1da177e4 LT |
3005 | } |
3006 | ||
d4cf970d EP |
3007 | static noinline int audit_inode_permission(struct inode *inode, |
3008 | u32 perms, u32 audited, u32 denied, | |
0188d5c0 | 3009 | int result) |
1da177e4 | 3010 | { |
b782e0a6 | 3011 | struct common_audit_data ad; |
80788c22 | 3012 | struct inode_security_struct *isec = selinux_inode(inode); |
d4cf970d EP |
3013 | int rc; |
3014 | ||
50c205f5 | 3015 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
3016 | ad.u.inode = inode; |
3017 | ||
6b6bc620 SS |
3018 | rc = slow_avc_audit(&selinux_state, |
3019 | current_sid(), isec->sid, isec->sclass, perms, | |
0188d5c0 | 3020 | audited, denied, result, &ad); |
d4cf970d EP |
3021 | if (rc) |
3022 | return rc; | |
3023 | return 0; | |
3024 | } | |
3025 | ||
e74f71eb | 3026 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 3027 | { |
88e67f3b | 3028 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
3029 | u32 perms; |
3030 | bool from_access; | |
5298d0b9 | 3031 | bool no_block = mask & MAY_NOT_BLOCK; |
2e334057 EP |
3032 | struct inode_security_struct *isec; |
3033 | u32 sid; | |
3034 | struct av_decision avd; | |
3035 | int rc, rc2; | |
3036 | u32 audited, denied; | |
1da177e4 | 3037 | |
b782e0a6 | 3038 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
3039 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
3040 | ||
b782e0a6 EP |
3041 | /* No permission to check. Existence test. */ |
3042 | if (!mask) | |
1da177e4 | 3043 | return 0; |
1da177e4 | 3044 | |
2e334057 | 3045 | validate_creds(cred); |
b782e0a6 | 3046 | |
2e334057 EP |
3047 | if (unlikely(IS_PRIVATE(inode))) |
3048 | return 0; | |
b782e0a6 EP |
3049 | |
3050 | perms = file_mask_to_av(inode->i_mode, mask); | |
3051 | ||
2e334057 | 3052 | sid = cred_sid(cred); |
5298d0b9 | 3053 | isec = inode_security_rcu(inode, no_block); |
5d226df4 AG |
3054 | if (IS_ERR(isec)) |
3055 | return PTR_ERR(isec); | |
2e334057 | 3056 | |
6b6bc620 | 3057 | rc = avc_has_perm_noaudit(&selinux_state, |
3a28cff3 | 3058 | sid, isec->sid, isec->sclass, perms, |
5298d0b9 | 3059 | no_block ? AVC_NONBLOCKING : 0, |
3a28cff3 | 3060 | &avd); |
2e334057 EP |
3061 | audited = avc_audit_required(perms, &avd, rc, |
3062 | from_access ? FILE__AUDIT_ACCESS : 0, | |
3063 | &denied); | |
3064 | if (likely(!audited)) | |
3065 | return rc; | |
3066 | ||
0188d5c0 | 3067 | /* fall back to ref-walk if we have to generate audit */ |
5298d0b9 | 3068 | if (no_block) |
0188d5c0 SS |
3069 | return -ECHILD; |
3070 | ||
3071 | rc2 = audit_inode_permission(inode, perms, audited, denied, rc); | |
2e334057 EP |
3072 | if (rc2) |
3073 | return rc2; | |
3074 | return rc; | |
1da177e4 LT |
3075 | } |
3076 | ||
3077 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
3078 | { | |
88e67f3b | 3079 | const struct cred *cred = current_cred(); |
ccb54478 | 3080 | struct inode *inode = d_backing_inode(dentry); |
bc6a6008 | 3081 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 3082 | __u32 av = FILE__WRITE; |
1da177e4 | 3083 | |
bc6a6008 AW |
3084 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
3085 | if (ia_valid & ATTR_FORCE) { | |
3086 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
3087 | ATTR_FORCE); | |
3088 | if (!ia_valid) | |
3089 | return 0; | |
3090 | } | |
1da177e4 | 3091 | |
bc6a6008 AW |
3092 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
3093 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 3094 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 3095 | |
aa8e712c | 3096 | if (selinux_policycap_openperm() && |
ccb54478 SS |
3097 | inode->i_sb->s_magic != SOCKFS_MAGIC && |
3098 | (ia_valid & ATTR_SIZE) && | |
3099 | !(ia_valid & ATTR_FILE)) | |
95dbf739 EP |
3100 | av |= FILE__OPEN; |
3101 | ||
3102 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
3103 | } |
3104 | ||
3f7036a0 | 3105 | static int selinux_inode_getattr(const struct path *path) |
1da177e4 | 3106 | { |
3f7036a0 | 3107 | return path_has_perm(current_cred(), path, FILE__GETATTR); |
1da177e4 LT |
3108 | } |
3109 | ||
db59000a SS |
3110 | static bool has_cap_mac_admin(bool audit) |
3111 | { | |
3112 | const struct cred *cred = current_cred(); | |
c1a85a00 | 3113 | unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; |
db59000a | 3114 | |
c1a85a00 | 3115 | if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) |
db59000a | 3116 | return false; |
c1a85a00 | 3117 | if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) |
db59000a SS |
3118 | return false; |
3119 | return true; | |
3120 | } | |
3121 | ||
8f0cfa52 DH |
3122 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
3123 | const void *value, size_t size, int flags) | |
1da177e4 | 3124 | { |
c6f493d6 | 3125 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3126 | struct inode_security_struct *isec; |
1da177e4 | 3127 | struct superblock_security_struct *sbsec; |
2bf49690 | 3128 | struct common_audit_data ad; |
275bb41e | 3129 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
3130 | int rc = 0; |
3131 | ||
6b240306 EB |
3132 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3133 | rc = cap_inode_setxattr(dentry, name, value, size, flags); | |
3134 | if (rc) | |
3135 | return rc; | |
3136 | ||
3137 | /* Not an attribute we recognize, so just check the | |
3138 | ordinary setattr permission. */ | |
3139 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3140 | } | |
1da177e4 | 3141 | |
65cddd50 | 3142 | if (!selinux_initialized(&selinux_state)) |
3e3e24b4 JL |
3143 | return (inode_owner_or_capable(inode) ? 0 : -EPERM); |
3144 | ||
1da177e4 | 3145 | sbsec = inode->i_sb->s_security; |
12f348b9 | 3146 | if (!(sbsec->flags & SBLABEL_MNT)) |
1da177e4 LT |
3147 | return -EOPNOTSUPP; |
3148 | ||
2e149670 | 3149 | if (!inode_owner_or_capable(inode)) |
1da177e4 LT |
3150 | return -EPERM; |
3151 | ||
50c205f5 | 3152 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 3153 | ad.u.dentry = dentry; |
1da177e4 | 3154 | |
20cdef8d | 3155 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
3156 | rc = avc_has_perm(&selinux_state, |
3157 | sid, isec->sid, isec->sclass, | |
1da177e4 LT |
3158 | FILE__RELABELFROM, &ad); |
3159 | if (rc) | |
3160 | return rc; | |
3161 | ||
aa8e712c SS |
3162 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3163 | GFP_KERNEL); | |
12b29f34 | 3164 | if (rc == -EINVAL) { |
db59000a | 3165 | if (!has_cap_mac_admin(true)) { |
d6ea83ec EP |
3166 | struct audit_buffer *ab; |
3167 | size_t audit_size; | |
d6ea83ec EP |
3168 | |
3169 | /* We strip a nul only if it is at the end, otherwise the | |
3170 | * context contains a nul and we should audit that */ | |
e3fea3f7 | 3171 | if (value) { |
add24372 CIK |
3172 | const char *str = value; |
3173 | ||
e3fea3f7 AV |
3174 | if (str[size - 1] == '\0') |
3175 | audit_size = size - 1; | |
3176 | else | |
3177 | audit_size = size; | |
3178 | } else { | |
e3fea3f7 AV |
3179 | audit_size = 0; |
3180 | } | |
cdfb6b34 RGB |
3181 | ab = audit_log_start(audit_context(), |
3182 | GFP_ATOMIC, AUDIT_SELINUX_ERR); | |
d6ea83ec EP |
3183 | audit_log_format(ab, "op=setxattr invalid_context="); |
3184 | audit_log_n_untrustedstring(ab, value, audit_size); | |
3185 | audit_log_end(ab); | |
3186 | ||
12b29f34 | 3187 | return rc; |
d6ea83ec | 3188 | } |
aa8e712c SS |
3189 | rc = security_context_to_sid_force(&selinux_state, value, |
3190 | size, &newsid); | |
12b29f34 | 3191 | } |
1da177e4 LT |
3192 | if (rc) |
3193 | return rc; | |
3194 | ||
6b6bc620 SS |
3195 | rc = avc_has_perm(&selinux_state, |
3196 | sid, newsid, isec->sclass, | |
1da177e4 LT |
3197 | FILE__RELABELTO, &ad); |
3198 | if (rc) | |
3199 | return rc; | |
3200 | ||
aa8e712c SS |
3201 | rc = security_validate_transition(&selinux_state, isec->sid, newsid, |
3202 | sid, isec->sclass); | |
1da177e4 LT |
3203 | if (rc) |
3204 | return rc; | |
3205 | ||
6b6bc620 SS |
3206 | return avc_has_perm(&selinux_state, |
3207 | newsid, | |
1da177e4 LT |
3208 | sbsec->sid, |
3209 | SECCLASS_FILESYSTEM, | |
3210 | FILESYSTEM__ASSOCIATE, | |
3211 | &ad); | |
3212 | } | |
3213 | ||
8f0cfa52 | 3214 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 3215 | const void *value, size_t size, |
8f0cfa52 | 3216 | int flags) |
1da177e4 | 3217 | { |
c6f493d6 | 3218 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3219 | struct inode_security_struct *isec; |
1da177e4 LT |
3220 | u32 newsid; |
3221 | int rc; | |
3222 | ||
3223 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
3224 | /* Not an attribute we recognize, so nothing to do. */ | |
3225 | return; | |
3226 | } | |
3227 | ||
65cddd50 | 3228 | if (!selinux_initialized(&selinux_state)) { |
3e3e24b4 JL |
3229 | /* If we haven't even been initialized, then we can't validate |
3230 | * against a policy, so leave the label as invalid. It may | |
3231 | * resolve to a valid label on the next revalidation try if | |
3232 | * we've since initialized. | |
3233 | */ | |
3234 | return; | |
3235 | } | |
3236 | ||
aa8e712c SS |
3237 | rc = security_context_to_sid_force(&selinux_state, value, size, |
3238 | &newsid); | |
1da177e4 | 3239 | if (rc) { |
c103a91e | 3240 | pr_err("SELinux: unable to map context to SID" |
12b29f34 SS |
3241 | "for (%s, %lu), rc=%d\n", |
3242 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
3243 | return; |
3244 | } | |
3245 | ||
20cdef8d | 3246 | isec = backing_inode_security(dentry); |
9287aed2 | 3247 | spin_lock(&isec->lock); |
aa9c2669 | 3248 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3249 | isec->sid = newsid; |
6f3be9f5 | 3250 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3251 | spin_unlock(&isec->lock); |
aa9c2669 | 3252 | |
1da177e4 LT |
3253 | return; |
3254 | } | |
3255 | ||
8f0cfa52 | 3256 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
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 | ||
828dfe1d | 3263 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 3264 | { |
88e67f3b DH |
3265 | const struct cred *cred = current_cred(); |
3266 | ||
2875fa00 | 3267 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3268 | } |
3269 | ||
8f0cfa52 | 3270 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 3271 | { |
6b240306 EB |
3272 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3273 | int rc = cap_inode_removexattr(dentry, name); | |
3274 | if (rc) | |
3275 | return rc; | |
3276 | ||
3277 | /* Not an attribute we recognize, so just check the | |
3278 | ordinary setattr permission. */ | |
3279 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3280 | } | |
1da177e4 | 3281 | |
9530a3e0 SS |
3282 | if (!selinux_initialized(&selinux_state)) |
3283 | return 0; | |
3284 | ||
1da177e4 LT |
3285 | /* No one is allowed to remove a SELinux security label. |
3286 | You can change the label, but all data must be labeled. */ | |
3287 | return -EACCES; | |
3288 | } | |
3289 | ||
ac5656d8 AG |
3290 | static int selinux_path_notify(const struct path *path, u64 mask, |
3291 | unsigned int obj_type) | |
3292 | { | |
3293 | int ret; | |
3294 | u32 perm; | |
3295 | ||
3296 | struct common_audit_data ad; | |
3297 | ||
3298 | ad.type = LSM_AUDIT_DATA_PATH; | |
3299 | ad.u.path = *path; | |
3300 | ||
3301 | /* | |
3302 | * Set permission needed based on the type of mark being set. | |
3303 | * Performs an additional check for sb watches. | |
3304 | */ | |
3305 | switch (obj_type) { | |
3306 | case FSNOTIFY_OBJ_TYPE_VFSMOUNT: | |
3307 | perm = FILE__WATCH_MOUNT; | |
3308 | break; | |
3309 | case FSNOTIFY_OBJ_TYPE_SB: | |
3310 | perm = FILE__WATCH_SB; | |
3311 | ret = superblock_has_perm(current_cred(), path->dentry->d_sb, | |
3312 | FILESYSTEM__WATCH, &ad); | |
3313 | if (ret) | |
3314 | return ret; | |
3315 | break; | |
3316 | case FSNOTIFY_OBJ_TYPE_INODE: | |
3317 | perm = FILE__WATCH; | |
3318 | break; | |
3319 | default: | |
3320 | return -EINVAL; | |
3321 | } | |
3322 | ||
3323 | /* blocking watches require the file:watch_with_perm permission */ | |
3324 | if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) | |
3325 | perm |= FILE__WATCH_WITH_PERM; | |
3326 | ||
3327 | /* watches on read-like events need the file:watch_reads permission */ | |
3328 | if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) | |
3329 | perm |= FILE__WATCH_READS; | |
3330 | ||
3331 | return path_has_perm(current_cred(), path, perm); | |
3332 | } | |
3333 | ||
d381d8a9 | 3334 | /* |
abc69bb6 | 3335 | * Copy the inode security context value to the user. |
d381d8a9 JM |
3336 | * |
3337 | * Permission check is handled by selinux_inode_getxattr hook. | |
3338 | */ | |
ea861dfd | 3339 | static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 3340 | { |
42492594 DQ |
3341 | u32 size; |
3342 | int error; | |
3343 | char *context = NULL; | |
20cdef8d | 3344 | struct inode_security_struct *isec; |
d381d8a9 | 3345 | |
c8e22261 JL |
3346 | /* |
3347 | * If we're not initialized yet, then we can't validate contexts, so | |
3348 | * just let vfs_getxattr fall back to using the on-disk xattr. | |
3349 | */ | |
3350 | if (!selinux_initialized(&selinux_state) || | |
3351 | strcmp(name, XATTR_SELINUX_SUFFIX)) | |
8c8570fb | 3352 | return -EOPNOTSUPP; |
d381d8a9 | 3353 | |
abc69bb6 SS |
3354 | /* |
3355 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3356 | * value even if it is not defined by current policy; otherwise, | |
3357 | * use the in-core value under current policy. | |
3358 | * Use the non-auditing forms of the permission checks since | |
3359 | * getxattr may be called by unprivileged processes commonly | |
3360 | * and lack of permission just means that we fall back to the | |
3361 | * in-core context value, not a denial. | |
3362 | */ | |
20cdef8d | 3363 | isec = inode_security(inode); |
db59000a | 3364 | if (has_cap_mac_admin(false)) |
aa8e712c SS |
3365 | error = security_sid_to_context_force(&selinux_state, |
3366 | isec->sid, &context, | |
abc69bb6 SS |
3367 | &size); |
3368 | else | |
aa8e712c SS |
3369 | error = security_sid_to_context(&selinux_state, isec->sid, |
3370 | &context, &size); | |
42492594 DQ |
3371 | if (error) |
3372 | return error; | |
3373 | error = size; | |
3374 | if (alloc) { | |
3375 | *buffer = context; | |
3376 | goto out_nofree; | |
3377 | } | |
3378 | kfree(context); | |
3379 | out_nofree: | |
3380 | return error; | |
1da177e4 LT |
3381 | } |
3382 | ||
3383 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 3384 | const void *value, size_t size, int flags) |
1da177e4 | 3385 | { |
2c97165b | 3386 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
53e0c2aa | 3387 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; |
1da177e4 LT |
3388 | u32 newsid; |
3389 | int rc; | |
3390 | ||
3391 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3392 | return -EOPNOTSUPP; | |
3393 | ||
53e0c2aa OM |
3394 | if (!(sbsec->flags & SBLABEL_MNT)) |
3395 | return -EOPNOTSUPP; | |
3396 | ||
1da177e4 LT |
3397 | if (!value || !size) |
3398 | return -EACCES; | |
3399 | ||
aa8e712c SS |
3400 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3401 | GFP_KERNEL); | |
1da177e4 LT |
3402 | if (rc) |
3403 | return rc; | |
3404 | ||
9287aed2 | 3405 | spin_lock(&isec->lock); |
aa9c2669 | 3406 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3407 | isec->sid = newsid; |
6f3be9f5 | 3408 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3409 | spin_unlock(&isec->lock); |
1da177e4 LT |
3410 | return 0; |
3411 | } | |
3412 | ||
3413 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3414 | { | |
3415 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3416 | if (buffer && len <= buffer_size) | |
3417 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3418 | return len; | |
3419 | } | |
3420 | ||
d6335d77 | 3421 | static void selinux_inode_getsecid(struct inode *inode, u32 *secid) |
713a04ae | 3422 | { |
e817c2f3 | 3423 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
713a04ae AD |
3424 | *secid = isec->sid; |
3425 | } | |
3426 | ||
56909eb3 VG |
3427 | static int selinux_inode_copy_up(struct dentry *src, struct cred **new) |
3428 | { | |
3429 | u32 sid; | |
3430 | struct task_security_struct *tsec; | |
3431 | struct cred *new_creds = *new; | |
3432 | ||
3433 | if (new_creds == NULL) { | |
3434 | new_creds = prepare_creds(); | |
3435 | if (!new_creds) | |
3436 | return -ENOMEM; | |
3437 | } | |
3438 | ||
0c6cfa62 | 3439 | tsec = selinux_cred(new_creds); |
56909eb3 VG |
3440 | /* Get label from overlay inode and set it in create_sid */ |
3441 | selinux_inode_getsecid(d_inode(src), &sid); | |
3442 | tsec->create_sid = sid; | |
3443 | *new = new_creds; | |
3444 | return 0; | |
3445 | } | |
3446 | ||
19472b69 VG |
3447 | static int selinux_inode_copy_up_xattr(const char *name) |
3448 | { | |
3449 | /* The copy_up hook above sets the initial context on an inode, but we | |
3450 | * don't then want to overwrite it by blindly copying all the lower | |
3451 | * xattrs up. Instead, we have to filter out SELinux-related xattrs. | |
3452 | */ | |
3453 | if (strcmp(name, XATTR_NAME_SELINUX) == 0) | |
3454 | return 1; /* Discard */ | |
3455 | /* | |
3456 | * Any other attribute apart from SELINUX is not claimed, supported | |
3457 | * by selinux. | |
3458 | */ | |
3459 | return -EOPNOTSUPP; | |
3460 | } | |
3461 | ||
ec882da5 OM |
3462 | /* kernfs node operations */ |
3463 | ||
c72c4cde Y |
3464 | static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, |
3465 | struct kernfs_node *kn) | |
ec882da5 | 3466 | { |
169ce0c0 | 3467 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
ec882da5 OM |
3468 | u32 parent_sid, newsid, clen; |
3469 | int rc; | |
3470 | char *context; | |
3471 | ||
1537ad15 | 3472 | rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); |
ec882da5 OM |
3473 | if (rc == -ENODATA) |
3474 | return 0; | |
3475 | else if (rc < 0) | |
3476 | return rc; | |
3477 | ||
3478 | clen = (u32)rc; | |
3479 | context = kmalloc(clen, GFP_KERNEL); | |
3480 | if (!context) | |
3481 | return -ENOMEM; | |
3482 | ||
1537ad15 | 3483 | rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); |
ec882da5 OM |
3484 | if (rc < 0) { |
3485 | kfree(context); | |
3486 | return rc; | |
3487 | } | |
3488 | ||
3489 | rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid, | |
3490 | GFP_KERNEL); | |
3491 | kfree(context); | |
3492 | if (rc) | |
3493 | return rc; | |
3494 | ||
3495 | if (tsec->create_sid) { | |
3496 | newsid = tsec->create_sid; | |
3497 | } else { | |
3498 | u16 secclass = inode_mode_to_security_class(kn->mode); | |
3499 | struct qstr q; | |
3500 | ||
3501 | q.name = kn->name; | |
3502 | q.hash_len = hashlen_string(kn_dir, kn->name); | |
3503 | ||
3504 | rc = security_transition_sid(&selinux_state, tsec->sid, | |
3505 | parent_sid, secclass, &q, | |
3506 | &newsid); | |
3507 | if (rc) | |
3508 | return rc; | |
3509 | } | |
3510 | ||
3511 | rc = security_sid_to_context_force(&selinux_state, newsid, | |
3512 | &context, &clen); | |
3513 | if (rc) | |
3514 | return rc; | |
3515 | ||
1537ad15 OM |
3516 | rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, |
3517 | XATTR_CREATE); | |
ec882da5 OM |
3518 | kfree(context); |
3519 | return rc; | |
3520 | } | |
3521 | ||
3522 | ||
1da177e4 LT |
3523 | /* file security operations */ |
3524 | ||
788e7dd4 | 3525 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3526 | { |
88e67f3b | 3527 | const struct cred *cred = current_cred(); |
496ad9aa | 3528 | struct inode *inode = file_inode(file); |
1da177e4 | 3529 | |
1da177e4 LT |
3530 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3531 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3532 | mask |= MAY_APPEND; | |
3533 | ||
389fb800 PM |
3534 | return file_has_perm(cred, file, |
3535 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3536 | } |
3537 | ||
788e7dd4 YN |
3538 | static int selinux_file_permission(struct file *file, int mask) |
3539 | { | |
496ad9aa | 3540 | struct inode *inode = file_inode(file); |
bb6c6b02 | 3541 | struct file_security_struct *fsec = selinux_file(file); |
b197367e | 3542 | struct inode_security_struct *isec; |
20dda18b SS |
3543 | u32 sid = current_sid(); |
3544 | ||
389fb800 | 3545 | if (!mask) |
788e7dd4 YN |
3546 | /* No permission to check. Existence test. */ |
3547 | return 0; | |
788e7dd4 | 3548 | |
b197367e | 3549 | isec = inode_security(inode); |
20dda18b | 3550 | if (sid == fsec->sid && fsec->isid == isec->sid && |
6b6bc620 | 3551 | fsec->pseqno == avc_policy_seqno(&selinux_state)) |
83d49856 | 3552 | /* No change since file_open check. */ |
20dda18b SS |
3553 | return 0; |
3554 | ||
788e7dd4 YN |
3555 | return selinux_revalidate_file_permission(file, mask); |
3556 | } | |
3557 | ||
1da177e4 LT |
3558 | static int selinux_file_alloc_security(struct file *file) |
3559 | { | |
cb89e246 PM |
3560 | struct file_security_struct *fsec = selinux_file(file); |
3561 | u32 sid = current_sid(); | |
3562 | ||
3563 | fsec->sid = sid; | |
3564 | fsec->fown_sid = sid; | |
3565 | ||
3566 | return 0; | |
1da177e4 LT |
3567 | } |
3568 | ||
fa1aa143 JVS |
3569 | /* |
3570 | * Check whether a task has the ioctl permission and cmd | |
3571 | * operation to an inode. | |
3572 | */ | |
1d2a168a | 3573 | static int ioctl_has_perm(const struct cred *cred, struct file *file, |
fa1aa143 JVS |
3574 | u32 requested, u16 cmd) |
3575 | { | |
3576 | struct common_audit_data ad; | |
bb6c6b02 | 3577 | struct file_security_struct *fsec = selinux_file(file); |
fa1aa143 | 3578 | struct inode *inode = file_inode(file); |
20cdef8d | 3579 | struct inode_security_struct *isec; |
fa1aa143 JVS |
3580 | struct lsm_ioctlop_audit ioctl; |
3581 | u32 ssid = cred_sid(cred); | |
3582 | int rc; | |
3583 | u8 driver = cmd >> 8; | |
3584 | u8 xperm = cmd & 0xff; | |
3585 | ||
3586 | ad.type = LSM_AUDIT_DATA_IOCTL_OP; | |
3587 | ad.u.op = &ioctl; | |
3588 | ad.u.op->cmd = cmd; | |
3589 | ad.u.op->path = file->f_path; | |
3590 | ||
3591 | if (ssid != fsec->sid) { | |
6b6bc620 SS |
3592 | rc = avc_has_perm(&selinux_state, |
3593 | ssid, fsec->sid, | |
fa1aa143 JVS |
3594 | SECCLASS_FD, |
3595 | FD__USE, | |
3596 | &ad); | |
3597 | if (rc) | |
3598 | goto out; | |
3599 | } | |
3600 | ||
3601 | if (unlikely(IS_PRIVATE(inode))) | |
3602 | return 0; | |
3603 | ||
20cdef8d | 3604 | isec = inode_security(inode); |
6b6bc620 SS |
3605 | rc = avc_has_extended_perms(&selinux_state, |
3606 | ssid, isec->sid, isec->sclass, | |
3607 | requested, driver, xperm, &ad); | |
fa1aa143 JVS |
3608 | out: |
3609 | return rc; | |
3610 | } | |
3611 | ||
1da177e4 LT |
3612 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
3613 | unsigned long arg) | |
3614 | { | |
88e67f3b | 3615 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3616 | int error = 0; |
1da177e4 | 3617 | |
0b24dcb7 EP |
3618 | switch (cmd) { |
3619 | case FIONREAD: | |
0b24dcb7 | 3620 | case FIBMAP: |
0b24dcb7 | 3621 | case FIGETBSZ: |
2f99c369 | 3622 | case FS_IOC_GETFLAGS: |
2f99c369 | 3623 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3624 | error = file_has_perm(cred, file, FILE__GETATTR); |
3625 | break; | |
1da177e4 | 3626 | |
2f99c369 | 3627 | case FS_IOC_SETFLAGS: |
2f99c369 | 3628 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3629 | error = file_has_perm(cred, file, FILE__SETATTR); |
3630 | break; | |
3631 | ||
3632 | /* sys_ioctl() checks */ | |
3633 | case FIONBIO: | |
0b24dcb7 EP |
3634 | case FIOASYNC: |
3635 | error = file_has_perm(cred, file, 0); | |
3636 | break; | |
1da177e4 | 3637 | |
0b24dcb7 EP |
3638 | case KDSKBENT: |
3639 | case KDSKBSENT: | |
6a9de491 | 3640 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
c1a85a00 | 3641 | CAP_OPT_NONE, true); |
0b24dcb7 EP |
3642 | break; |
3643 | ||
3644 | /* default case assumes that the command will go | |
3645 | * to the file's ioctl() function. | |
3646 | */ | |
3647 | default: | |
fa1aa143 | 3648 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
0b24dcb7 EP |
3649 | } |
3650 | return error; | |
1da177e4 LT |
3651 | } |
3652 | ||
b78b7d59 | 3653 | static int default_noexec __ro_after_init; |
fcaaade1 | 3654 | |
1da177e4 LT |
3655 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3656 | { | |
88e67f3b | 3657 | const struct cred *cred = current_cred(); |
be0554c9 | 3658 | u32 sid = cred_sid(cred); |
d84f4f99 | 3659 | int rc = 0; |
88e67f3b | 3660 | |
fcaaade1 | 3661 | if (default_noexec && |
892e8cac SS |
3662 | (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || |
3663 | (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3664 | /* |
3665 | * We are making executable an anonymous mapping or a | |
3666 | * private file mapping that will also be writable. | |
3667 | * This has an additional check. | |
3668 | */ | |
6b6bc620 SS |
3669 | rc = avc_has_perm(&selinux_state, |
3670 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3671 | PROCESS__EXECMEM, NULL); |
1da177e4 | 3672 | if (rc) |
d84f4f99 | 3673 | goto error; |
1da177e4 | 3674 | } |
1da177e4 LT |
3675 | |
3676 | if (file) { | |
3677 | /* read access is always possible with a mapping */ | |
3678 | u32 av = FILE__READ; | |
3679 | ||
3680 | /* write access only matters if the mapping is shared */ | |
3681 | if (shared && (prot & PROT_WRITE)) | |
3682 | av |= FILE__WRITE; | |
3683 | ||
3684 | if (prot & PROT_EXEC) | |
3685 | av |= FILE__EXECUTE; | |
3686 | ||
88e67f3b | 3687 | return file_has_perm(cred, file, av); |
1da177e4 | 3688 | } |
d84f4f99 DH |
3689 | |
3690 | error: | |
3691 | return rc; | |
1da177e4 LT |
3692 | } |
3693 | ||
e5467859 | 3694 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3695 | { |
b1d9e6b0 | 3696 | int rc = 0; |
1da177e4 | 3697 | |
a2551df7 | 3698 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
98883bfd | 3699 | u32 sid = current_sid(); |
6b6bc620 SS |
3700 | rc = avc_has_perm(&selinux_state, |
3701 | sid, sid, SECCLASS_MEMPROTECT, | |
ed032189 | 3702 | MEMPROTECT__MMAP_ZERO, NULL); |
84336d1a EP |
3703 | } |
3704 | ||
98883bfd | 3705 | return rc; |
e5467859 | 3706 | } |
1da177e4 | 3707 | |
e5467859 AV |
3708 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3709 | unsigned long prot, unsigned long flags) | |
3710 | { | |
3ba4bf5f SS |
3711 | struct common_audit_data ad; |
3712 | int rc; | |
3713 | ||
3714 | if (file) { | |
3715 | ad.type = LSM_AUDIT_DATA_FILE; | |
3716 | ad.u.file = file; | |
3717 | rc = inode_has_perm(current_cred(), file_inode(file), | |
3718 | FILE__MAP, &ad); | |
3719 | if (rc) | |
3720 | return rc; | |
3721 | } | |
3722 | ||
8861d0af | 3723 | if (checkreqprot_get(&selinux_state)) |
1da177e4 LT |
3724 | prot = reqprot; |
3725 | ||
3726 | return file_map_prot_check(file, prot, | |
3727 | (flags & MAP_TYPE) == MAP_SHARED); | |
3728 | } | |
3729 | ||
3730 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3731 | unsigned long reqprot, | |
3732 | unsigned long prot) | |
3733 | { | |
88e67f3b | 3734 | const struct cred *cred = current_cred(); |
be0554c9 | 3735 | u32 sid = cred_sid(cred); |
1da177e4 | 3736 | |
8861d0af | 3737 | if (checkreqprot_get(&selinux_state)) |
1da177e4 LT |
3738 | prot = reqprot; |
3739 | ||
fcaaade1 SS |
3740 | if (default_noexec && |
3741 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3742 | int rc = 0; |
db4c9641 SS |
3743 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3744 | vma->vm_end <= vma->vm_mm->brk) { | |
6b6bc620 SS |
3745 | rc = avc_has_perm(&selinux_state, |
3746 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3747 | PROCESS__EXECHEAP, NULL); |
db4c9641 | 3748 | } else if (!vma->vm_file && |
c2316dbf SS |
3749 | ((vma->vm_start <= vma->vm_mm->start_stack && |
3750 | vma->vm_end >= vma->vm_mm->start_stack) || | |
d17af505 | 3751 | vma_is_stack_for_current(vma))) { |
6b6bc620 SS |
3752 | rc = avc_has_perm(&selinux_state, |
3753 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3754 | PROCESS__EXECSTACK, NULL); |
db4c9641 SS |
3755 | } else if (vma->vm_file && vma->anon_vma) { |
3756 | /* | |
3757 | * We are making executable a file mapping that has | |
3758 | * had some COW done. Since pages might have been | |
3759 | * written, check ability to execute the possibly | |
3760 | * modified content. This typically should only | |
3761 | * occur for text relocations. | |
3762 | */ | |
d84f4f99 | 3763 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3764 | } |