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d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * NSA Security-Enhanced Linux (SELinux) security module | |
4 | * | |
5 | * This file contains the SELinux hook function implementations. | |
6 | * | |
7efbb60b | 7 | * Authors: Stephen Smalley, <sds@tycho.nsa.gov> |
828dfe1d EP |
8 | * Chris Vance, <cvance@nai.com> |
9 | * Wayne Salamon, <wsalamon@nai.com> | |
10 | * James Morris <jmorris@redhat.com> | |
1da177e4 LT |
11 | * |
12 | * Copyright (C) 2001,2002 Networks Associates Technology, Inc. | |
2069f457 EP |
13 | * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> |
14 | * Eric Paris <eparis@redhat.com> | |
1da177e4 | 15 | * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. |
828dfe1d | 16 | * <dgoeddel@trustedcs.com> |
ed6d76e4 | 17 | * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. |
82c21bfa | 18 | * Paul Moore <paul@paul-moore.com> |
788e7dd4 | 19 | * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. |
828dfe1d | 20 | * Yuichi Nakamura <ynakam@hitachisoft.jp> |
3a976fa6 | 21 | * Copyright (C) 2016 Mellanox Technologies |
1da177e4 LT |
22 | */ |
23 | ||
1da177e4 | 24 | #include <linux/init.h> |
0b24dcb7 | 25 | #include <linux/kd.h> |
1da177e4 | 26 | #include <linux/kernel.h> |
b89999d0 | 27 | #include <linux/kernel_read_file.h> |
1da177e4 | 28 | #include <linux/errno.h> |
3f07c014 | 29 | #include <linux/sched/signal.h> |
29930025 | 30 | #include <linux/sched/task.h> |
3c4ed7bd | 31 | #include <linux/lsm_hooks.h> |
1da177e4 LT |
32 | #include <linux/xattr.h> |
33 | #include <linux/capability.h> | |
34 | #include <linux/unistd.h> | |
35 | #include <linux/mm.h> | |
36 | #include <linux/mman.h> | |
37 | #include <linux/slab.h> | |
38 | #include <linux/pagemap.h> | |
0b24dcb7 | 39 | #include <linux/proc_fs.h> |
1da177e4 | 40 | #include <linux/swap.h> |
1da177e4 LT |
41 | #include <linux/spinlock.h> |
42 | #include <linux/syscalls.h> | |
2a7dba39 | 43 | #include <linux/dcache.h> |
1da177e4 | 44 | #include <linux/file.h> |
9f3acc31 | 45 | #include <linux/fdtable.h> |
1da177e4 LT |
46 | #include <linux/namei.h> |
47 | #include <linux/mount.h> | |
442155c1 DH |
48 | #include <linux/fs_context.h> |
49 | #include <linux/fs_parser.h> | |
1da177e4 LT |
50 | #include <linux/netfilter_ipv4.h> |
51 | #include <linux/netfilter_ipv6.h> | |
52 | #include <linux/tty.h> | |
53 | #include <net/icmp.h> | |
227b60f5 | 54 | #include <net/ip.h> /* for local_port_range[] */ |
1da177e4 | 55 | #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ |
47180068 | 56 | #include <net/inet_connection_sock.h> |
220deb96 | 57 | #include <net/net_namespace.h> |
d621d35e | 58 | #include <net/netlabel.h> |
f5269710 | 59 | #include <linux/uaccess.h> |
1da177e4 | 60 | #include <asm/ioctls.h> |
60063497 | 61 | #include <linux/atomic.h> |
1da177e4 LT |
62 | #include <linux/bitops.h> |
63 | #include <linux/interrupt.h> | |
64 | #include <linux/netdevice.h> /* for network interface checks */ | |
77954983 | 65 | #include <net/netlink.h> |
1da177e4 LT |
66 | #include <linux/tcp.h> |
67 | #include <linux/udp.h> | |
2ee92d46 | 68 | #include <linux/dccp.h> |
d452930f RH |
69 | #include <linux/sctp.h> |
70 | #include <net/sctp/structs.h> | |
1da177e4 LT |
71 | #include <linux/quota.h> |
72 | #include <linux/un.h> /* for Unix socket types */ | |
73 | #include <net/af_unix.h> /* for Unix socket types */ | |
74 | #include <linux/parser.h> | |
75 | #include <linux/nfs_mount.h> | |
76 | #include <net/ipv6.h> | |
77 | #include <linux/hugetlb.h> | |
78 | #include <linux/personality.h> | |
1da177e4 | 79 | #include <linux/audit.h> |
6931dfc9 | 80 | #include <linux/string.h> |
23970741 | 81 | #include <linux/mutex.h> |
f06febc9 | 82 | #include <linux/posix-timers.h> |
00234592 | 83 | #include <linux/syslog.h> |
3486740a | 84 | #include <linux/user_namespace.h> |
44fc7ea0 | 85 | #include <linux/export.h> |
40401530 AV |
86 | #include <linux/msg.h> |
87 | #include <linux/shm.h> | |
ec27c356 | 88 | #include <linux/bpf.h> |
ec882da5 OM |
89 | #include <linux/kernfs.h> |
90 | #include <linux/stringhash.h> /* for hashlen_string() */ | |
e262e32d | 91 | #include <uapi/linux/mount.h> |
ac5656d8 AG |
92 | #include <linux/fsnotify.h> |
93 | #include <linux/fanotify.h> | |
f4d653dc | 94 | #include <linux/io_uring.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 | 148 | if (checkreqprot) |
81200b02 | 149 | pr_err("SELinux: checkreqprot set to 1 via kernel parameter. This is deprecated and will be rejected in a future kernel release.\n"); |
e9c38f9f | 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 LT |
213 | { |
214 | struct task_security_struct *tsec; | |
215 | ||
cdeea454 | 216 | tsec = selinux_cred(unrcu_pointer(current->real_cred)); |
d84f4f99 | 217 | tsec->osid = tsec->sid = SECINITSID_KERNEL; |
1da177e4 LT |
218 | } |
219 | ||
88e67f3b DH |
220 | /* |
221 | * get the security ID of a set of credentials | |
222 | */ | |
223 | static inline u32 cred_sid(const struct cred *cred) | |
224 | { | |
225 | const struct task_security_struct *tsec; | |
226 | ||
0c6cfa62 | 227 | tsec = selinux_cred(cred); |
88e67f3b DH |
228 | return tsec->sid; |
229 | } | |
230 | ||
275bb41e | 231 | /* |
3b11a1de | 232 | * get the objective security ID of a task |
275bb41e | 233 | */ |
eb1231f7 | 234 | static inline u32 task_sid_obj(const struct task_struct *task) |
275bb41e | 235 | { |
275bb41e DH |
236 | u32 sid; |
237 | ||
238 | rcu_read_lock(); | |
88e67f3b | 239 | sid = cred_sid(__task_cred(task)); |
275bb41e DH |
240 | rcu_read_unlock(); |
241 | return sid; | |
242 | } | |
243 | ||
5d226df4 AG |
244 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); |
245 | ||
246 | /* | |
247 | * Try reloading inode security labels that have been marked as invalid. The | |
248 | * @may_sleep parameter indicates when sleeping and thus reloading labels is | |
42059112 | 249 | * allowed; when set to false, returns -ECHILD when the label is |
e9193288 | 250 | * invalid. The @dentry parameter should be set to a dentry of the inode. |
5d226df4 AG |
251 | */ |
252 | static int __inode_security_revalidate(struct inode *inode, | |
e9193288 | 253 | struct dentry *dentry, |
5d226df4 AG |
254 | bool may_sleep) |
255 | { | |
80788c22 | 256 | struct inode_security_struct *isec = selinux_inode(inode); |
5d226df4 AG |
257 | |
258 | might_sleep_if(may_sleep); | |
259 | ||
65cddd50 | 260 | if (selinux_initialized(&selinux_state) && |
aa8e712c | 261 | isec->initialized != LABEL_INITIALIZED) { |
5d226df4 AG |
262 | if (!may_sleep) |
263 | return -ECHILD; | |
264 | ||
265 | /* | |
266 | * Try reloading the inode security label. This will fail if | |
267 | * @opt_dentry is NULL and no dentry for this inode can be | |
268 | * found; in that case, continue using the old label. | |
269 | */ | |
e9193288 | 270 | inode_doinit_with_dentry(inode, dentry); |
5d226df4 AG |
271 | } |
272 | return 0; | |
273 | } | |
274 | ||
5d226df4 AG |
275 | static struct inode_security_struct *inode_security_novalidate(struct inode *inode) |
276 | { | |
80788c22 | 277 | return selinux_inode(inode); |
5d226df4 AG |
278 | } |
279 | ||
280 | static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) | |
281 | { | |
282 | int error; | |
283 | ||
284 | error = __inode_security_revalidate(inode, NULL, !rcu); | |
285 | if (error) | |
286 | return ERR_PTR(error); | |
80788c22 | 287 | return selinux_inode(inode); |
5d226df4 AG |
288 | } |
289 | ||
83da53c5 AG |
290 | /* |
291 | * Get the security label of an inode. | |
292 | */ | |
293 | static struct inode_security_struct *inode_security(struct inode *inode) | |
294 | { | |
5d226df4 | 295 | __inode_security_revalidate(inode, NULL, true); |
80788c22 | 296 | return selinux_inode(inode); |
83da53c5 AG |
297 | } |
298 | ||
2c97165b PM |
299 | static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) |
300 | { | |
301 | struct inode *inode = d_backing_inode(dentry); | |
302 | ||
80788c22 | 303 | return selinux_inode(inode); |
2c97165b PM |
304 | } |
305 | ||
83da53c5 AG |
306 | /* |
307 | * Get the security label of a dentry's backing inode. | |
308 | */ | |
309 | static struct inode_security_struct *backing_inode_security(struct dentry *dentry) | |
310 | { | |
311 | struct inode *inode = d_backing_inode(dentry); | |
312 | ||
5d226df4 | 313 | __inode_security_revalidate(inode, dentry, true); |
80788c22 | 314 | return selinux_inode(inode); |
83da53c5 AG |
315 | } |
316 | ||
1da177e4 LT |
317 | static void inode_free_security(struct inode *inode) |
318 | { | |
80788c22 | 319 | struct inode_security_struct *isec = selinux_inode(inode); |
afb1cbe3 | 320 | struct superblock_security_struct *sbsec; |
1da177e4 | 321 | |
afb1cbe3 CS |
322 | if (!isec) |
323 | return; | |
1aea7808 | 324 | sbsec = selinux_superblock(inode->i_sb); |
9629d04a WL |
325 | /* |
326 | * As not all inode security structures are in a list, we check for | |
327 | * empty list outside of the lock to make sure that we won't waste | |
328 | * time taking a lock doing nothing. | |
329 | * | |
330 | * The list_del_init() function can be safely called more than once. | |
331 | * It should not be possible for this function to be called with | |
332 | * concurrent list_add(), but for better safety against future changes | |
333 | * in the code, we use list_empty_careful() here. | |
334 | */ | |
335 | if (!list_empty_careful(&isec->list)) { | |
336 | spin_lock(&sbsec->isec_lock); | |
1da177e4 | 337 | list_del_init(&isec->list); |
9629d04a WL |
338 | spin_unlock(&sbsec->isec_lock); |
339 | } | |
1da177e4 LT |
340 | } |
341 | ||
bd323655 | 342 | struct selinux_mnt_opts { |
b8b87fd9 SM |
343 | u32 fscontext_sid; |
344 | u32 context_sid; | |
345 | u32 rootcontext_sid; | |
346 | u32 defcontext_sid; | |
bd323655 AV |
347 | }; |
348 | ||
204cc0cc AV |
349 | static void selinux_free_mnt_opts(void *mnt_opts) |
350 | { | |
70f4169a | 351 | kfree(mnt_opts); |
204cc0cc AV |
352 | } |
353 | ||
1da177e4 | 354 | enum { |
31e87930 | 355 | Opt_error = -1, |
442155c1 DH |
356 | Opt_context = 0, |
357 | Opt_defcontext = 1, | |
1da177e4 | 358 | Opt_fscontext = 2, |
442155c1 DH |
359 | Opt_rootcontext = 3, |
360 | Opt_seclabel = 4, | |
1da177e4 LT |
361 | }; |
362 | ||
da3d76ab | 363 | #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg} |
169d68ef AV |
364 | static struct { |
365 | const char *name; | |
366 | int len; | |
367 | int opt; | |
368 | bool has_arg; | |
369 | } tokens[] = { | |
da3d76ab AV |
370 | A(context, true), |
371 | A(fscontext, true), | |
372 | A(defcontext, true), | |
373 | A(rootcontext, true), | |
374 | A(seclabel, false), | |
1da177e4 | 375 | }; |
169d68ef AV |
376 | #undef A |
377 | ||
378 | static int match_opt_prefix(char *s, int l, char **arg) | |
379 | { | |
380 | int i; | |
381 | ||
382 | for (i = 0; i < ARRAY_SIZE(tokens); i++) { | |
383 | size_t len = tokens[i].len; | |
384 | if (len > l || memcmp(s, tokens[i].name, len)) | |
385 | continue; | |
386 | if (tokens[i].has_arg) { | |
387 | if (len == l || s[len] != '=') | |
388 | continue; | |
389 | *arg = s + len + 1; | |
390 | } else if (len != l) | |
391 | continue; | |
392 | return tokens[i].opt; | |
393 | } | |
394 | return Opt_error; | |
395 | } | |
1da177e4 LT |
396 | |
397 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
398 | ||
c312feb2 EP |
399 | static int may_context_mount_sb_relabel(u32 sid, |
400 | struct superblock_security_struct *sbsec, | |
275bb41e | 401 | const struct cred *cred) |
c312feb2 | 402 | { |
0c6cfa62 | 403 | const struct task_security_struct *tsec = selinux_cred(cred); |
c312feb2 EP |
404 | int rc; |
405 | ||
6b6bc620 SS |
406 | rc = avc_has_perm(&selinux_state, |
407 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
408 | FILESYSTEM__RELABELFROM, NULL); |
409 | if (rc) | |
410 | return rc; | |
411 | ||
6b6bc620 SS |
412 | rc = avc_has_perm(&selinux_state, |
413 | tsec->sid, sid, SECCLASS_FILESYSTEM, | |
c312feb2 EP |
414 | FILESYSTEM__RELABELTO, NULL); |
415 | return rc; | |
416 | } | |
417 | ||
0808925e EP |
418 | static int may_context_mount_inode_relabel(u32 sid, |
419 | struct superblock_security_struct *sbsec, | |
275bb41e | 420 | const struct cred *cred) |
0808925e | 421 | { |
0c6cfa62 | 422 | const struct task_security_struct *tsec = selinux_cred(cred); |
0808925e | 423 | int rc; |
6b6bc620 SS |
424 | rc = avc_has_perm(&selinux_state, |
425 | tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
426 | FILESYSTEM__RELABELFROM, NULL); |
427 | if (rc) | |
428 | return rc; | |
429 | ||
6b6bc620 SS |
430 | rc = avc_has_perm(&selinux_state, |
431 | sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
0808925e EP |
432 | FILESYSTEM__ASSOCIATE, NULL); |
433 | return rc; | |
434 | } | |
435 | ||
a83d6dda | 436 | static int selinux_is_genfs_special_handling(struct super_block *sb) |
b43e725d | 437 | { |
a83d6dda OM |
438 | /* Special handling. Genfs but also in-core setxattr handler */ |
439 | return !strcmp(sb->s_type->name, "sysfs") || | |
d5f3a5f6 MS |
440 | !strcmp(sb->s_type->name, "pstore") || |
441 | !strcmp(sb->s_type->name, "debugfs") || | |
a2c7c6fb | 442 | !strcmp(sb->s_type->name, "tracefs") || |
2651225b | 443 | !strcmp(sb->s_type->name, "rootfs") || |
aa8e712c | 444 | (selinux_policycap_cgroupseclabel() && |
2651225b SS |
445 | (!strcmp(sb->s_type->name, "cgroup") || |
446 | !strcmp(sb->s_type->name, "cgroup2"))); | |
b43e725d EP |
447 | } |
448 | ||
a83d6dda OM |
449 | static int selinux_is_sblabel_mnt(struct super_block *sb) |
450 | { | |
1aea7808 | 451 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
a83d6dda OM |
452 | |
453 | /* | |
454 | * IMPORTANT: Double-check logic in this function when adding a new | |
455 | * SECURITY_FS_USE_* definition! | |
456 | */ | |
457 | BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7); | |
458 | ||
459 | switch (sbsec->behavior) { | |
460 | case SECURITY_FS_USE_XATTR: | |
461 | case SECURITY_FS_USE_TRANS: | |
462 | case SECURITY_FS_USE_TASK: | |
463 | case SECURITY_FS_USE_NATIVE: | |
464 | return 1; | |
465 | ||
466 | case SECURITY_FS_USE_GENFS: | |
467 | return selinux_is_genfs_special_handling(sb); | |
468 | ||
469 | /* Never allow relabeling on context mounts */ | |
470 | case SECURITY_FS_USE_MNTPOINT: | |
471 | case SECURITY_FS_USE_NONE: | |
472 | default: | |
473 | return 0; | |
474 | } | |
475 | } | |
476 | ||
08abe46b OM |
477 | static int sb_check_xattr_support(struct super_block *sb) |
478 | { | |
0266c25e | 479 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
08abe46b OM |
480 | struct dentry *root = sb->s_root; |
481 | struct inode *root_inode = d_backing_inode(root); | |
482 | u32 sid; | |
483 | int rc; | |
484 | ||
485 | /* | |
486 | * Make sure that the xattr handler exists and that no | |
487 | * error other than -ENODATA is returned by getxattr on | |
488 | * the root directory. -ENODATA is ok, as this may be | |
489 | * the first boot of the SELinux kernel before we have | |
490 | * assigned xattr values to the filesystem. | |
491 | */ | |
492 | if (!(root_inode->i_opflags & IOP_XATTR)) { | |
493 | pr_warn("SELinux: (dev %s, type %s) has no xattr support\n", | |
494 | sb->s_id, sb->s_type->name); | |
495 | goto fallback; | |
496 | } | |
497 | ||
498 | rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); | |
499 | if (rc < 0 && rc != -ENODATA) { | |
500 | if (rc == -EOPNOTSUPP) { | |
501 | pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n", | |
502 | sb->s_id, sb->s_type->name); | |
503 | goto fallback; | |
504 | } else { | |
505 | pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n", | |
506 | sb->s_id, sb->s_type->name, -rc); | |
507 | return rc; | |
508 | } | |
509 | } | |
510 | return 0; | |
511 | ||
512 | fallback: | |
513 | /* No xattr support - try to fallback to genfs if possible. */ | |
514 | rc = security_genfs_sid(&selinux_state, sb->s_type->name, "/", | |
515 | SECCLASS_DIR, &sid); | |
516 | if (rc) | |
517 | return -EOPNOTSUPP; | |
518 | ||
519 | pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n", | |
520 | sb->s_id, sb->s_type->name); | |
521 | sbsec->behavior = SECURITY_FS_USE_GENFS; | |
522 | sbsec->sid = sid; | |
523 | return 0; | |
524 | } | |
525 | ||
c9180a57 | 526 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 527 | { |
1aea7808 | 528 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
c9180a57 | 529 | struct dentry *root = sb->s_root; |
c6f493d6 | 530 | struct inode *root_inode = d_backing_inode(root); |
c9180a57 | 531 | int rc = 0; |
1da177e4 | 532 | |
c9180a57 | 533 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
08abe46b OM |
534 | rc = sb_check_xattr_support(sb); |
535 | if (rc) | |
536 | return rc; | |
c9180a57 | 537 | } |
1da177e4 | 538 | |
eadcabc6 | 539 | sbsec->flags |= SE_SBINITIALIZED; |
0b4d3452 SM |
540 | |
541 | /* | |
542 | * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply | |
543 | * leave the flag untouched because sb_clone_mnt_opts might be handing | |
544 | * us a superblock that needs the flag to be cleared. | |
545 | */ | |
b43e725d | 546 | if (selinux_is_sblabel_mnt(sb)) |
12f348b9 | 547 | sbsec->flags |= SBLABEL_MNT; |
0b4d3452 SM |
548 | else |
549 | sbsec->flags &= ~SBLABEL_MNT; | |
ddd29ec6 | 550 | |
c9180a57 EP |
551 | /* Initialize the root inode. */ |
552 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 553 | |
c9180a57 EP |
554 | /* Initialize any other inodes associated with the superblock, e.g. |
555 | inodes created prior to initial policy load or inodes created | |
556 | during get_sb by a pseudo filesystem that directly | |
557 | populates itself. */ | |
558 | spin_lock(&sbsec->isec_lock); | |
8d64124a | 559 | while (!list_empty(&sbsec->isec_head)) { |
c9180a57 | 560 | struct inode_security_struct *isec = |
8d64124a | 561 | list_first_entry(&sbsec->isec_head, |
c9180a57 EP |
562 | struct inode_security_struct, list); |
563 | struct inode *inode = isec->inode; | |
923190d3 | 564 | list_del_init(&isec->list); |
c9180a57 EP |
565 | spin_unlock(&sbsec->isec_lock); |
566 | inode = igrab(inode); | |
567 | if (inode) { | |
568 | if (!IS_PRIVATE(inode)) | |
cb89e246 | 569 | inode_doinit_with_dentry(inode, NULL); |
c9180a57 EP |
570 | iput(inode); |
571 | } | |
572 | spin_lock(&sbsec->isec_lock); | |
c9180a57 EP |
573 | } |
574 | spin_unlock(&sbsec->isec_lock); | |
c9180a57 EP |
575 | return rc; |
576 | } | |
1da177e4 | 577 | |
c9180a57 EP |
578 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
579 | u32 old_sid, u32 new_sid) | |
580 | { | |
0d90a7ec DQ |
581 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
582 | ||
c9180a57 | 583 | /* check if the old mount command had the same options */ |
0d90a7ec | 584 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
585 | if (!(sbsec->flags & flag) || |
586 | (old_sid != new_sid)) | |
587 | return 1; | |
588 | ||
589 | /* check if we were passed the same options twice, | |
590 | * aka someone passed context=a,context=b | |
591 | */ | |
0d90a7ec DQ |
592 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
593 | if (mnt_flags & flag) | |
c9180a57 EP |
594 | return 1; |
595 | return 0; | |
596 | } | |
e0007529 | 597 | |
c9180a57 EP |
598 | /* |
599 | * Allow filesystems with binary mount data to explicitly set mount point | |
600 | * labeling information. | |
601 | */ | |
e0007529 | 602 | static int selinux_set_mnt_opts(struct super_block *sb, |
204cc0cc | 603 | void *mnt_opts, |
649f6e77 DQ |
604 | unsigned long kern_flags, |
605 | unsigned long *set_kern_flags) | |
c9180a57 | 606 | { |
275bb41e | 607 | const struct cred *cred = current_cred(); |
1aea7808 | 608 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
b159e86b | 609 | struct dentry *root = sb->s_root; |
bd323655 | 610 | struct selinux_mnt_opts *opts = mnt_opts; |
2c97165b | 611 | struct inode_security_struct *root_isec; |
c9180a57 EP |
612 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
613 | u32 defcontext_sid = 0; | |
bd323655 | 614 | int rc = 0; |
c9180a57 EP |
615 | |
616 | mutex_lock(&sbsec->lock); | |
617 | ||
65cddd50 | 618 | if (!selinux_initialized(&selinux_state)) { |
bd323655 | 619 | if (!opts) { |
c9180a57 EP |
620 | /* Defer initialization until selinux_complete_init, |
621 | after the initial policy is loaded and the security | |
622 | server is ready to handle calls. */ | |
c9180a57 EP |
623 | goto out; |
624 | } | |
625 | rc = -EINVAL; | |
c103a91e | 626 | pr_warn("SELinux: Unable to set superblock options " |
744ba35e | 627 | "before the security server is initialized\n"); |
1da177e4 | 628 | goto out; |
c9180a57 | 629 | } |
649f6e77 DQ |
630 | if (kern_flags && !set_kern_flags) { |
631 | /* Specifying internal flags without providing a place to | |
632 | * place the results is not allowed */ | |
633 | rc = -EINVAL; | |
634 | goto out; | |
635 | } | |
1da177e4 | 636 | |
e0007529 EP |
637 | /* |
638 | * Binary mount data FS will come through this function twice. Once | |
639 | * from an explicit call and once from the generic calls from the vfs. | |
640 | * Since the generic VFS calls will not contain any security mount data | |
641 | * we need to skip the double mount verification. | |
642 | * | |
643 | * This does open a hole in which we will not notice if the first | |
9691e4f9 | 644 | * mount using this sb set explicit options and a second mount using |
e0007529 EP |
645 | * this sb does not set any security options. (The first options |
646 | * will be used for both mounts) | |
647 | */ | |
0d90a7ec | 648 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
bd323655 | 649 | && !opts) |
f5269710 | 650 | goto out; |
e0007529 | 651 | |
2c97165b PM |
652 | root_isec = backing_inode_security_novalidate(root); |
653 | ||
c9180a57 EP |
654 | /* |
655 | * parse the mount options, check if they are valid sids. | |
656 | * also check if someone is trying to mount the same sb more | |
657 | * than once with different security options. | |
658 | */ | |
bd323655 | 659 | if (opts) { |
70f4169a OM |
660 | if (opts->fscontext_sid) { |
661 | fscontext_sid = opts->fscontext_sid; | |
c9180a57 EP |
662 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, |
663 | fscontext_sid)) | |
664 | goto out_double_mount; | |
c9180a57 | 665 | sbsec->flags |= FSCONTEXT_MNT; |
bd323655 | 666 | } |
70f4169a OM |
667 | if (opts->context_sid) { |
668 | context_sid = opts->context_sid; | |
c9180a57 EP |
669 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, |
670 | context_sid)) | |
671 | goto out_double_mount; | |
c9180a57 | 672 | sbsec->flags |= CONTEXT_MNT; |
bd323655 | 673 | } |
70f4169a OM |
674 | if (opts->rootcontext_sid) { |
675 | rootcontext_sid = opts->rootcontext_sid; | |
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 | 680 | } |
70f4169a OM |
681 | if (opts->defcontext_sid) { |
682 | defcontext_sid = opts->defcontext_sid; | |
c9180a57 EP |
683 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, |
684 | defcontext_sid)) | |
685 | goto out_double_mount; | |
c9180a57 | 686 | sbsec->flags |= DEFCONTEXT_MNT; |
1da177e4 | 687 | } |
c9180a57 EP |
688 | } |
689 | ||
0d90a7ec | 690 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 691 | /* previously mounted with options, but not on this attempt? */ |
bd323655 | 692 | if ((sbsec->flags & SE_MNTMASK) && !opts) |
c9180a57 EP |
693 | goto out_double_mount; |
694 | rc = 0; | |
695 | goto out; | |
696 | } | |
697 | ||
089be43e | 698 | if (strcmp(sb->s_type->name, "proc") == 0) |
134509d5 SS |
699 | sbsec->flags |= SE_SBPROC | SE_SBGENFS; |
700 | ||
8e014720 | 701 | if (!strcmp(sb->s_type->name, "debugfs") || |
6a391183 | 702 | !strcmp(sb->s_type->name, "tracefs") || |
a20456ae | 703 | !strcmp(sb->s_type->name, "binder") || |
4ca54d3d | 704 | !strcmp(sb->s_type->name, "bpf") || |
8a764ef1 CG |
705 | !strcmp(sb->s_type->name, "pstore") || |
706 | !strcmp(sb->s_type->name, "securityfs")) | |
b754026b OM |
707 | sbsec->flags |= SE_SBGENFS; |
708 | ||
709 | if (!strcmp(sb->s_type->name, "sysfs") || | |
901ef845 AM |
710 | !strcmp(sb->s_type->name, "cgroup") || |
711 | !strcmp(sb->s_type->name, "cgroup2")) | |
b754026b | 712 | sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR; |
c9180a57 | 713 | |
eb9ae686 DQ |
714 | if (!sbsec->behavior) { |
715 | /* | |
716 | * Determine the labeling behavior to use for this | |
717 | * filesystem type. | |
718 | */ | |
aa8e712c | 719 | rc = security_fs_use(&selinux_state, sb); |
eb9ae686 | 720 | if (rc) { |
c103a91e | 721 | pr_warn("%s: security_fs_use(%s) returned %d\n", |
eb9ae686 DQ |
722 | __func__, sb->s_type->name, rc); |
723 | goto out; | |
724 | } | |
c9180a57 | 725 | } |
aad82892 SF |
726 | |
727 | /* | |
01593d32 SS |
728 | * If this is a user namespace mount and the filesystem type is not |
729 | * explicitly whitelisted, then no contexts are allowed on the command | |
730 | * line and security labels must be ignored. | |
aad82892 | 731 | */ |
01593d32 SS |
732 | if (sb->s_user_ns != &init_user_ns && |
733 | strcmp(sb->s_type->name, "tmpfs") && | |
734 | strcmp(sb->s_type->name, "ramfs") && | |
7fa2e79a VG |
735 | strcmp(sb->s_type->name, "devpts") && |
736 | strcmp(sb->s_type->name, "overlay")) { | |
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 | { | |
1aea7808 CS |
839 | struct superblock_security_struct *old = selinux_superblock(oldsb); |
840 | struct superblock_security_struct *new = selinux_superblock(newsb); | |
094f7b69 JL |
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; |
1aea7808 CS |
872 | const struct superblock_security_struct *oldsbsec = |
873 | selinux_superblock(oldsb); | |
874 | struct superblock_security_struct *newsbsec = selinux_superblock(newsb); | |
1da177e4 | 875 | |
c9180a57 EP |
876 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
877 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
878 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 879 | |
0f5e6420 EP |
880 | /* |
881 | * if the parent was able to be mounted it clearly had no special lsm | |
e8c26255 | 882 | * mount options. thus we can safely deal with this superblock later |
0f5e6420 | 883 | */ |
65cddd50 | 884 | if (!selinux_initialized(&selinux_state)) |
094f7b69 | 885 | return 0; |
c9180a57 | 886 | |
0b4d3452 SM |
887 | /* |
888 | * Specifying internal flags without providing a place to | |
889 | * place the results is not allowed. | |
890 | */ | |
891 | if (kern_flags && !set_kern_flags) | |
892 | return -EINVAL; | |
893 | ||
c9180a57 | 894 | /* how can we clone if the old one wasn't set up?? */ |
0d90a7ec | 895 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
c9180a57 | 896 | |
094f7b69 | 897 | /* if fs is reusing a sb, make sure that the contexts match */ |
3815a245 BF |
898 | if (newsbsec->flags & SE_SBINITIALIZED) { |
899 | if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) | |
900 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
094f7b69 | 901 | return selinux_cmp_sb_context(oldsb, newsb); |
3815a245 | 902 | } |
5a552617 | 903 | |
c9180a57 EP |
904 | mutex_lock(&newsbsec->lock); |
905 | ||
906 | newsbsec->flags = oldsbsec->flags; | |
907 | ||
908 | newsbsec->sid = oldsbsec->sid; | |
909 | newsbsec->def_sid = oldsbsec->def_sid; | |
910 | newsbsec->behavior = oldsbsec->behavior; | |
911 | ||
0b4d3452 SM |
912 | if (newsbsec->behavior == SECURITY_FS_USE_NATIVE && |
913 | !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) { | |
aa8e712c | 914 | rc = security_fs_use(&selinux_state, newsb); |
0b4d3452 SM |
915 | if (rc) |
916 | goto out; | |
917 | } | |
918 | ||
919 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) { | |
920 | newsbsec->behavior = SECURITY_FS_USE_NATIVE; | |
921 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
922 | } | |
923 | ||
c9180a57 EP |
924 | if (set_context) { |
925 | u32 sid = oldsbsec->mntpoint_sid; | |
926 | ||
927 | if (!set_fscontext) | |
928 | newsbsec->sid = sid; | |
929 | if (!set_rootcontext) { | |
83da53c5 | 930 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); |
c9180a57 EP |
931 | newisec->sid = sid; |
932 | } | |
933 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 934 | } |
c9180a57 | 935 | if (set_rootcontext) { |
83da53c5 AG |
936 | const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); |
937 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); | |
1da177e4 | 938 | |
c9180a57 | 939 | newisec->sid = oldisec->sid; |
1da177e4 LT |
940 | } |
941 | ||
c9180a57 | 942 | sb_finish_set_opts(newsb); |
0b4d3452 | 943 | out: |
c9180a57 | 944 | mutex_unlock(&newsbsec->lock); |
0b4d3452 | 945 | return rc; |
c9180a57 EP |
946 | } |
947 | ||
ef54ccb6 XJ |
948 | /* |
949 | * NOTE: the caller is resposible for freeing the memory even if on error. | |
950 | */ | |
ba641862 | 951 | static int selinux_add_opt(int token, const char *s, void **mnt_opts) |
c9180a57 | 952 | { |
ba641862 | 953 | struct selinux_mnt_opts *opts = *mnt_opts; |
70f4169a OM |
954 | u32 *dst_sid; |
955 | int rc; | |
1da177e4 | 956 | |
6cd9d4b9 PM |
957 | if (token == Opt_seclabel) |
958 | /* eaten and completely ignored */ | |
169d68ef | 959 | return 0; |
2e08df3c | 960 | if (!s) |
ef54ccb6 | 961 | return -EINVAL; |
e0007529 | 962 | |
70f4169a OM |
963 | if (!selinux_initialized(&selinux_state)) { |
964 | pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n"); | |
965 | return -EINVAL; | |
966 | } | |
967 | ||
ba641862 | 968 | if (!opts) { |
6cd9d4b9 | 969 | opts = kzalloc(sizeof(*opts), GFP_KERNEL); |
ba641862 AV |
970 | if (!opts) |
971 | return -ENOMEM; | |
972 | *mnt_opts = opts; | |
c9180a57 | 973 | } |
2e08df3c | 974 | |
ba641862 AV |
975 | switch (token) { |
976 | case Opt_context: | |
70f4169a | 977 | if (opts->context_sid || opts->defcontext_sid) |
6cd9d4b9 | 978 | goto err; |
70f4169a | 979 | dst_sid = &opts->context_sid; |
ba641862 AV |
980 | break; |
981 | case Opt_fscontext: | |
70f4169a | 982 | if (opts->fscontext_sid) |
6cd9d4b9 | 983 | goto err; |
70f4169a | 984 | dst_sid = &opts->fscontext_sid; |
ba641862 AV |
985 | break; |
986 | case Opt_rootcontext: | |
70f4169a | 987 | if (opts->rootcontext_sid) |
6cd9d4b9 | 988 | goto err; |
70f4169a | 989 | dst_sid = &opts->rootcontext_sid; |
ba641862 AV |
990 | break; |
991 | case Opt_defcontext: | |
70f4169a | 992 | if (opts->context_sid || opts->defcontext_sid) |
6cd9d4b9 | 993 | goto err; |
70f4169a | 994 | dst_sid = &opts->defcontext_sid; |
ba641862 | 995 | break; |
70f4169a OM |
996 | default: |
997 | WARN_ON(1); | |
998 | return -EINVAL; | |
c9180a57 | 999 | } |
70f4169a OM |
1000 | rc = security_context_str_to_sid(&selinux_state, s, dst_sid, GFP_KERNEL); |
1001 | if (rc) | |
1002 | pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n", | |
1003 | s, rc); | |
1004 | return rc; | |
e2e0e097 | 1005 | |
6cd9d4b9 | 1006 | err: |
ba641862 | 1007 | pr_warn(SEL_MOUNT_FAIL_MSG); |
ba641862 | 1008 | return -EINVAL; |
e0007529 | 1009 | } |
1da177e4 | 1010 | |
e3489f89 | 1011 | static int show_sid(struct seq_file *m, u32 sid) |
2069f457 | 1012 | { |
e3489f89 AV |
1013 | char *context = NULL; |
1014 | u32 len; | |
1015 | int rc; | |
11689d47 | 1016 | |
e3489f89 AV |
1017 | rc = security_sid_to_context(&selinux_state, sid, |
1018 | &context, &len); | |
1019 | if (!rc) { | |
4d3d0ed6 | 1020 | bool has_comma = strchr(context, ','); |
2069f457 | 1021 | |
442155c1 | 1022 | seq_putc(m, '='); |
2069f457 EP |
1023 | if (has_comma) |
1024 | seq_putc(m, '\"'); | |
e3489f89 | 1025 | seq_escape(m, context, "\"\n\\"); |
2069f457 EP |
1026 | if (has_comma) |
1027 | seq_putc(m, '\"'); | |
1028 | } | |
e3489f89 AV |
1029 | kfree(context); |
1030 | return rc; | |
2069f457 EP |
1031 | } |
1032 | ||
1033 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1034 | { | |
1aea7808 | 1035 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
2069f457 EP |
1036 | int rc; |
1037 | ||
e3489f89 AV |
1038 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
1039 | return 0; | |
2069f457 | 1040 | |
65cddd50 | 1041 | if (!selinux_initialized(&selinux_state)) |
e3489f89 | 1042 | return 0; |
2069f457 | 1043 | |
e3489f89 AV |
1044 | if (sbsec->flags & FSCONTEXT_MNT) { |
1045 | seq_putc(m, ','); | |
1046 | seq_puts(m, FSCONTEXT_STR); | |
1047 | rc = show_sid(m, sbsec->sid); | |
1048 | if (rc) | |
1049 | return rc; | |
1050 | } | |
1051 | if (sbsec->flags & CONTEXT_MNT) { | |
1052 | seq_putc(m, ','); | |
1053 | seq_puts(m, CONTEXT_STR); | |
1054 | rc = show_sid(m, sbsec->mntpoint_sid); | |
1055 | if (rc) | |
1056 | return rc; | |
1057 | } | |
1058 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
1059 | seq_putc(m, ','); | |
1060 | seq_puts(m, DEFCONTEXT_STR); | |
1061 | rc = show_sid(m, sbsec->def_sid); | |
1062 | if (rc) | |
1063 | return rc; | |
1064 | } | |
1065 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
b159e86b | 1066 | struct dentry *root = sb->s_root; |
e3489f89 AV |
1067 | struct inode_security_struct *isec = backing_inode_security(root); |
1068 | seq_putc(m, ','); | |
1069 | seq_puts(m, ROOTCONTEXT_STR); | |
1070 | rc = show_sid(m, isec->sid); | |
1071 | if (rc) | |
1072 | return rc; | |
1073 | } | |
1074 | if (sbsec->flags & SBLABEL_MNT) { | |
1075 | seq_putc(m, ','); | |
442155c1 | 1076 | seq_puts(m, SECLABEL_STR); |
e3489f89 AV |
1077 | } |
1078 | return 0; | |
2069f457 EP |
1079 | } |
1080 | ||
1da177e4 LT |
1081 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1082 | { | |
1083 | switch (mode & S_IFMT) { | |
1084 | case S_IFSOCK: | |
1085 | return SECCLASS_SOCK_FILE; | |
1086 | case S_IFLNK: | |
1087 | return SECCLASS_LNK_FILE; | |
1088 | case S_IFREG: | |
1089 | return SECCLASS_FILE; | |
1090 | case S_IFBLK: | |
1091 | return SECCLASS_BLK_FILE; | |
1092 | case S_IFDIR: | |
1093 | return SECCLASS_DIR; | |
1094 | case S_IFCHR: | |
1095 | return SECCLASS_CHR_FILE; | |
1096 | case S_IFIFO: | |
1097 | return SECCLASS_FIFO_FILE; | |
1098 | ||
1099 | } | |
1100 | ||
1101 | return SECCLASS_FILE; | |
1102 | } | |
1103 | ||
13402580 JM |
1104 | static inline int default_protocol_stream(int protocol) |
1105 | { | |
95ca9072 PA |
1106 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP || |
1107 | protocol == IPPROTO_MPTCP); | |
13402580 JM |
1108 | } |
1109 | ||
1110 | static inline int default_protocol_dgram(int protocol) | |
1111 | { | |
1112 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1113 | } | |
1114 | ||
1da177e4 LT |
1115 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1116 | { | |
aa8e712c | 1117 | int extsockclass = selinux_policycap_extsockclass(); |
da69a530 | 1118 | |
1da177e4 LT |
1119 | switch (family) { |
1120 | case PF_UNIX: | |
1121 | switch (type) { | |
1122 | case SOCK_STREAM: | |
1123 | case SOCK_SEQPACKET: | |
1124 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1125 | case SOCK_DGRAM: | |
2a764b52 | 1126 | case SOCK_RAW: |
1da177e4 LT |
1127 | return SECCLASS_UNIX_DGRAM_SOCKET; |
1128 | } | |
1129 | break; | |
1130 | case PF_INET: | |
1131 | case PF_INET6: | |
1132 | switch (type) { | |
1133 | case SOCK_STREAM: | |
da69a530 | 1134 | case SOCK_SEQPACKET: |
13402580 JM |
1135 | if (default_protocol_stream(protocol)) |
1136 | return SECCLASS_TCP_SOCKET; | |
da69a530 SS |
1137 | else if (extsockclass && protocol == IPPROTO_SCTP) |
1138 | return SECCLASS_SCTP_SOCKET; | |
13402580 JM |
1139 | else |
1140 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1141 | case SOCK_DGRAM: |
13402580 JM |
1142 | if (default_protocol_dgram(protocol)) |
1143 | return SECCLASS_UDP_SOCKET; | |
ef37979a SS |
1144 | else if (extsockclass && (protocol == IPPROTO_ICMP || |
1145 | protocol == IPPROTO_ICMPV6)) | |
da69a530 | 1146 | return SECCLASS_ICMP_SOCKET; |
13402580 JM |
1147 | else |
1148 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1149 | case SOCK_DCCP: |
1150 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1151 | default: |
1da177e4 LT |
1152 | return SECCLASS_RAWIP_SOCKET; |
1153 | } | |
1154 | break; | |
1155 | case PF_NETLINK: | |
1156 | switch (protocol) { | |
1157 | case NETLINK_ROUTE: | |
1158 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
7f1fb60c | 1159 | case NETLINK_SOCK_DIAG: |
1da177e4 LT |
1160 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1161 | case NETLINK_NFLOG: | |
1162 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1163 | case NETLINK_XFRM: | |
1164 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1165 | case NETLINK_SELINUX: | |
1166 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
6c6d2e9b SS |
1167 | case NETLINK_ISCSI: |
1168 | return SECCLASS_NETLINK_ISCSI_SOCKET; | |
1da177e4 LT |
1169 | case NETLINK_AUDIT: |
1170 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
6c6d2e9b SS |
1171 | case NETLINK_FIB_LOOKUP: |
1172 | return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; | |
1173 | case NETLINK_CONNECTOR: | |
1174 | return SECCLASS_NETLINK_CONNECTOR_SOCKET; | |
1175 | case NETLINK_NETFILTER: | |
1176 | return SECCLASS_NETLINK_NETFILTER_SOCKET; | |
1da177e4 LT |
1177 | case NETLINK_DNRTMSG: |
1178 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1179 | case NETLINK_KOBJECT_UEVENT: |
1180 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
6c6d2e9b SS |
1181 | case NETLINK_GENERIC: |
1182 | return SECCLASS_NETLINK_GENERIC_SOCKET; | |
1183 | case NETLINK_SCSITRANSPORT: | |
1184 | return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; | |
1185 | case NETLINK_RDMA: | |
1186 | return SECCLASS_NETLINK_RDMA_SOCKET; | |
1187 | case NETLINK_CRYPTO: | |
1188 | return SECCLASS_NETLINK_CRYPTO_SOCKET; | |
1da177e4 LT |
1189 | default: |
1190 | return SECCLASS_NETLINK_SOCKET; | |
1191 | } | |
1192 | case PF_PACKET: | |
1193 | return SECCLASS_PACKET_SOCKET; | |
1194 | case PF_KEY: | |
1195 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1196 | case PF_APPLETALK: |
1197 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1198 | } |
1199 | ||
da69a530 SS |
1200 | if (extsockclass) { |
1201 | switch (family) { | |
1202 | case PF_AX25: | |
1203 | return SECCLASS_AX25_SOCKET; | |
1204 | case PF_IPX: | |
1205 | return SECCLASS_IPX_SOCKET; | |
1206 | case PF_NETROM: | |
1207 | return SECCLASS_NETROM_SOCKET; | |
da69a530 SS |
1208 | case PF_ATMPVC: |
1209 | return SECCLASS_ATMPVC_SOCKET; | |
1210 | case PF_X25: | |
1211 | return SECCLASS_X25_SOCKET; | |
1212 | case PF_ROSE: | |
1213 | return SECCLASS_ROSE_SOCKET; | |
1214 | case PF_DECnet: | |
1215 | return SECCLASS_DECNET_SOCKET; | |
1216 | case PF_ATMSVC: | |
1217 | return SECCLASS_ATMSVC_SOCKET; | |
1218 | case PF_RDS: | |
1219 | return SECCLASS_RDS_SOCKET; | |
1220 | case PF_IRDA: | |
1221 | return SECCLASS_IRDA_SOCKET; | |
1222 | case PF_PPPOX: | |
1223 | return SECCLASS_PPPOX_SOCKET; | |
1224 | case PF_LLC: | |
1225 | return SECCLASS_LLC_SOCKET; | |
da69a530 SS |
1226 | case PF_CAN: |
1227 | return SECCLASS_CAN_SOCKET; | |
1228 | case PF_TIPC: | |
1229 | return SECCLASS_TIPC_SOCKET; | |
1230 | case PF_BLUETOOTH: | |
1231 | return SECCLASS_BLUETOOTH_SOCKET; | |
1232 | case PF_IUCV: | |
1233 | return SECCLASS_IUCV_SOCKET; | |
1234 | case PF_RXRPC: | |
1235 | return SECCLASS_RXRPC_SOCKET; | |
1236 | case PF_ISDN: | |
1237 | return SECCLASS_ISDN_SOCKET; | |
1238 | case PF_PHONET: | |
1239 | return SECCLASS_PHONET_SOCKET; | |
1240 | case PF_IEEE802154: | |
1241 | return SECCLASS_IEEE802154_SOCKET; | |
1242 | case PF_CAIF: | |
1243 | return SECCLASS_CAIF_SOCKET; | |
1244 | case PF_ALG: | |
1245 | return SECCLASS_ALG_SOCKET; | |
1246 | case PF_NFC: | |
1247 | return SECCLASS_NFC_SOCKET; | |
1248 | case PF_VSOCK: | |
1249 | return SECCLASS_VSOCK_SOCKET; | |
1250 | case PF_KCM: | |
1251 | return SECCLASS_KCM_SOCKET; | |
1252 | case PF_QIPCRTR: | |
1253 | return SECCLASS_QIPCRTR_SOCKET; | |
3051bf36 LT |
1254 | case PF_SMC: |
1255 | return SECCLASS_SMC_SOCKET; | |
68e8b849 BT |
1256 | case PF_XDP: |
1257 | return SECCLASS_XDP_SOCKET; | |
bc49d816 JK |
1258 | case PF_MCTP: |
1259 | return SECCLASS_MCTP_SOCKET; | |
1260 | #if PF_MAX > 46 | |
da69a530 SS |
1261 | #error New address family defined, please update this function. |
1262 | #endif | |
1263 | } | |
1264 | } | |
1265 | ||
1da177e4 LT |
1266 | return SECCLASS_SOCKET; |
1267 | } | |
1268 | ||
134509d5 SS |
1269 | static int selinux_genfs_get_sid(struct dentry *dentry, |
1270 | u16 tclass, | |
1271 | u16 flags, | |
1272 | u32 *sid) | |
1da177e4 | 1273 | { |
8e6c9693 | 1274 | int rc; |
fc64005c | 1275 | struct super_block *sb = dentry->d_sb; |
8e6c9693 | 1276 | char *buffer, *path; |
1da177e4 | 1277 | |
828dfe1d | 1278 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1279 | if (!buffer) |
1280 | return -ENOMEM; | |
1281 | ||
8e6c9693 LAG |
1282 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1283 | if (IS_ERR(path)) | |
1284 | rc = PTR_ERR(path); | |
1285 | else { | |
134509d5 SS |
1286 | if (flags & SE_SBPROC) { |
1287 | /* each process gets a /proc/PID/ entry. Strip off the | |
1288 | * PID part to get a valid selinux labeling. | |
1289 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1290 | while (path[1] >= '0' && path[1] <= '9') { | |
1291 | path[1] = '/'; | |
1292 | path++; | |
1293 | } | |
8e6c9693 | 1294 | } |
aa8e712c SS |
1295 | rc = security_genfs_sid(&selinux_state, sb->s_type->name, |
1296 | path, tclass, sid); | |
7bb185ed SS |
1297 | if (rc == -ENOENT) { |
1298 | /* No match in policy, mark as unlabeled. */ | |
1299 | *sid = SECINITSID_UNLABELED; | |
1300 | rc = 0; | |
1301 | } | |
1da177e4 | 1302 | } |
1da177e4 LT |
1303 | free_page((unsigned long)buffer); |
1304 | return rc; | |
1305 | } | |
1da177e4 | 1306 | |
b754026b OM |
1307 | static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry, |
1308 | u32 def_sid, u32 *sid) | |
1309 | { | |
1310 | #define INITCONTEXTLEN 255 | |
1311 | char *context; | |
1312 | unsigned int len; | |
1313 | int rc; | |
1314 | ||
1315 | len = INITCONTEXTLEN; | |
1316 | context = kmalloc(len + 1, GFP_NOFS); | |
1317 | if (!context) | |
1318 | return -ENOMEM; | |
1319 | ||
1320 | context[len] = '\0'; | |
1321 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); | |
1322 | if (rc == -ERANGE) { | |
1323 | kfree(context); | |
1324 | ||
1325 | /* Need a larger buffer. Query for the right size. */ | |
1326 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); | |
1327 | if (rc < 0) | |
1328 | return rc; | |
1329 | ||
1330 | len = rc; | |
1331 | context = kmalloc(len + 1, GFP_NOFS); | |
1332 | if (!context) | |
1333 | return -ENOMEM; | |
1334 | ||
1335 | context[len] = '\0'; | |
1336 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, | |
1337 | context, len); | |
1338 | } | |
1339 | if (rc < 0) { | |
1340 | kfree(context); | |
1341 | if (rc != -ENODATA) { | |
1342 | pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n", | |
1343 | __func__, -rc, inode->i_sb->s_id, inode->i_ino); | |
1344 | return rc; | |
1345 | } | |
1346 | *sid = def_sid; | |
1347 | return 0; | |
1348 | } | |
1349 | ||
1350 | rc = security_context_to_sid_default(&selinux_state, context, rc, sid, | |
1351 | def_sid, GFP_NOFS); | |
1352 | if (rc) { | |
1353 | char *dev = inode->i_sb->s_id; | |
1354 | unsigned long ino = inode->i_ino; | |
1355 | ||
1356 | if (rc == -EINVAL) { | |
1357 | 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", | |
1358 | ino, dev, context); | |
1359 | } else { | |
1360 | pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n", | |
1361 | __func__, context, -rc, dev, ino); | |
1362 | } | |
1363 | } | |
1364 | kfree(context); | |
1365 | return 0; | |
1366 | } | |
1367 | ||
1da177e4 LT |
1368 | /* The inode's security attributes must be initialized before first use. */ |
1369 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1370 | { | |
1371 | struct superblock_security_struct *sbsec = NULL; | |
80788c22 | 1372 | struct inode_security_struct *isec = selinux_inode(inode); |
9287aed2 AG |
1373 | u32 task_sid, sid = 0; |
1374 | u16 sclass; | |
1da177e4 | 1375 | struct dentry *dentry; |
1da177e4 | 1376 | int rc = 0; |
1da177e4 | 1377 | |
6f3be9f5 | 1378 | if (isec->initialized == LABEL_INITIALIZED) |
13457d07 | 1379 | return 0; |
1da177e4 | 1380 | |
9287aed2 | 1381 | spin_lock(&isec->lock); |
6f3be9f5 | 1382 | if (isec->initialized == LABEL_INITIALIZED) |
23970741 | 1383 | goto out_unlock; |
1da177e4 | 1384 | |
13457d07 AG |
1385 | if (isec->sclass == SECCLASS_FILE) |
1386 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1387 | ||
1aea7808 | 1388 | sbsec = selinux_superblock(inode->i_sb); |
0d90a7ec | 1389 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1390 | /* Defer initialization until selinux_complete_init, |
1391 | after the initial policy is loaded and the security | |
1392 | server is ready to handle calls. */ | |
1393 | spin_lock(&sbsec->isec_lock); | |
1394 | if (list_empty(&isec->list)) | |
1395 | list_add(&isec->list, &sbsec->isec_head); | |
1396 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1397 | goto out_unlock; |
1da177e4 LT |
1398 | } |
1399 | ||
9287aed2 AG |
1400 | sclass = isec->sclass; |
1401 | task_sid = isec->task_sid; | |
1402 | sid = isec->sid; | |
1403 | isec->initialized = LABEL_PENDING; | |
1404 | spin_unlock(&isec->lock); | |
1405 | ||
1da177e4 | 1406 | switch (sbsec->behavior) { |
eb9ae686 DQ |
1407 | case SECURITY_FS_USE_NATIVE: |
1408 | break; | |
1da177e4 | 1409 | case SECURITY_FS_USE_XATTR: |
5d6c3191 | 1410 | if (!(inode->i_opflags & IOP_XATTR)) { |
9287aed2 | 1411 | sid = sbsec->def_sid; |
1da177e4 LT |
1412 | break; |
1413 | } | |
1da177e4 LT |
1414 | /* Need a dentry, since the xattr API requires one. |
1415 | Life would be simpler if we could just pass the inode. */ | |
1416 | if (opt_dentry) { | |
1417 | /* Called from d_instantiate or d_splice_alias. */ | |
1418 | dentry = dget(opt_dentry); | |
1419 | } else { | |
b127125d AV |
1420 | /* |
1421 | * Called from selinux_complete_init, try to find a dentry. | |
1422 | * Some filesystems really want a connected one, so try | |
1423 | * that first. We could split SECURITY_FS_USE_XATTR in | |
1424 | * two, depending upon that... | |
1425 | */ | |
1da177e4 | 1426 | dentry = d_find_alias(inode); |
b127125d AV |
1427 | if (!dentry) |
1428 | dentry = d_find_any_alias(inode); | |
1da177e4 LT |
1429 | } |
1430 | if (!dentry) { | |
df7f54c0 EP |
1431 | /* |
1432 | * this is can be hit on boot when a file is accessed | |
1433 | * before the policy is loaded. When we load policy we | |
1434 | * may find inodes that have no dentry on the | |
1435 | * sbsec->isec_head list. No reason to complain as these | |
1436 | * will get fixed up the next time we go through | |
1437 | * inode_doinit with a dentry, before these inodes could | |
1438 | * be used again by userspace. | |
1439 | */ | |
200ea5a2 | 1440 | goto out_invalid; |
1da177e4 LT |
1441 | } |
1442 | ||
b754026b OM |
1443 | rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid, |
1444 | &sid); | |
1da177e4 | 1445 | dput(dentry); |
b754026b OM |
1446 | if (rc) |
1447 | goto out; | |
1da177e4 LT |
1448 | break; |
1449 | case SECURITY_FS_USE_TASK: | |
9287aed2 | 1450 | sid = task_sid; |
1da177e4 LT |
1451 | break; |
1452 | case SECURITY_FS_USE_TRANS: | |
1453 | /* Default to the fs SID. */ | |
9287aed2 | 1454 | sid = sbsec->sid; |
1da177e4 LT |
1455 | |
1456 | /* Try to obtain a transition SID. */ | |
aa8e712c SS |
1457 | rc = security_transition_sid(&selinux_state, task_sid, sid, |
1458 | sclass, NULL, &sid); | |
1da177e4 | 1459 | if (rc) |
9287aed2 | 1460 | goto out; |
1da177e4 | 1461 | break; |
c312feb2 | 1462 | case SECURITY_FS_USE_MNTPOINT: |
9287aed2 | 1463 | sid = sbsec->mntpoint_sid; |
c312feb2 | 1464 | break; |
1da177e4 | 1465 | default: |
c312feb2 | 1466 | /* Default to the fs superblock SID. */ |
9287aed2 | 1467 | sid = sbsec->sid; |
1da177e4 | 1468 | |
7470d0d1 CG |
1469 | if ((sbsec->flags & SE_SBGENFS) && |
1470 | (!S_ISLNK(inode->i_mode) || | |
1471 | selinux_policycap_genfs_seclabel_symlinks())) { | |
f64410ec PM |
1472 | /* We must have a dentry to determine the label on |
1473 | * procfs inodes */ | |
b127125d | 1474 | if (opt_dentry) { |
f64410ec PM |
1475 | /* Called from d_instantiate or |
1476 | * d_splice_alias. */ | |
1477 | dentry = dget(opt_dentry); | |
b127125d | 1478 | } else { |
f64410ec | 1479 | /* Called from selinux_complete_init, try to |
b127125d AV |
1480 | * find a dentry. Some filesystems really want |
1481 | * a connected one, so try that first. | |
1482 | */ | |
f64410ec | 1483 | dentry = d_find_alias(inode); |
b127125d AV |
1484 | if (!dentry) |
1485 | dentry = d_find_any_alias(inode); | |
1486 | } | |
f64410ec PM |
1487 | /* |
1488 | * This can be hit on boot when a file is accessed | |
1489 | * before the policy is loaded. When we load policy we | |
1490 | * may find inodes that have no dentry on the | |
1491 | * sbsec->isec_head list. No reason to complain as | |
1492 | * these will get fixed up the next time we go through | |
1493 | * inode_doinit() with a dentry, before these inodes | |
1494 | * could be used again by userspace. | |
1495 | */ | |
1496 | if (!dentry) | |
200ea5a2 | 1497 | goto out_invalid; |
9287aed2 | 1498 | rc = selinux_genfs_get_sid(dentry, sclass, |
134509d5 | 1499 | sbsec->flags, &sid); |
b754026b OM |
1500 | if (rc) { |
1501 | dput(dentry); | |
9287aed2 | 1502 | goto out; |
b754026b OM |
1503 | } |
1504 | ||
1505 | if ((sbsec->flags & SE_SBGENFS_XATTR) && | |
1506 | (inode->i_opflags & IOP_XATTR)) { | |
1507 | rc = inode_doinit_use_xattr(inode, dentry, | |
1508 | sid, &sid); | |
1509 | if (rc) { | |
1510 | dput(dentry); | |
1511 | goto out; | |
1512 | } | |
1513 | } | |
1514 | dput(dentry); | |
1da177e4 LT |
1515 | } |
1516 | break; | |
1517 | } | |
1518 | ||
9287aed2 AG |
1519 | out: |
1520 | spin_lock(&isec->lock); | |
1521 | if (isec->initialized == LABEL_PENDING) { | |
200ea5a2 | 1522 | if (rc) { |
9287aed2 AG |
1523 | isec->initialized = LABEL_INVALID; |
1524 | goto out_unlock; | |
1525 | } | |
9287aed2 AG |
1526 | isec->initialized = LABEL_INITIALIZED; |
1527 | isec->sid = sid; | |
1528 | } | |
1da177e4 | 1529 | |
23970741 | 1530 | out_unlock: |
9287aed2 | 1531 | spin_unlock(&isec->lock); |
1da177e4 | 1532 | return rc; |
200ea5a2 PM |
1533 | |
1534 | out_invalid: | |
1535 | spin_lock(&isec->lock); | |
1536 | if (isec->initialized == LABEL_PENDING) { | |
1537 | isec->initialized = LABEL_INVALID; | |
1538 | isec->sid = sid; | |
1539 | } | |
1540 | spin_unlock(&isec->lock); | |
1541 | return 0; | |
1da177e4 LT |
1542 | } |
1543 | ||
1544 | /* Convert a Linux signal to an access vector. */ | |
1545 | static inline u32 signal_to_av(int sig) | |
1546 | { | |
1547 | u32 perm = 0; | |
1548 | ||
1549 | switch (sig) { | |
1550 | case SIGCHLD: | |
1551 | /* Commonly granted from child to parent. */ | |
1552 | perm = PROCESS__SIGCHLD; | |
1553 | break; | |
1554 | case SIGKILL: | |
1555 | /* Cannot be caught or ignored */ | |
1556 | perm = PROCESS__SIGKILL; | |
1557 | break; | |
1558 | case SIGSTOP: | |
1559 | /* Cannot be caught or ignored */ | |
1560 | perm = PROCESS__SIGSTOP; | |
1561 | break; | |
1562 | default: | |
1563 | /* All other signals. */ | |
1564 | perm = PROCESS__SIGNAL; | |
1565 | break; | |
1566 | } | |
1567 | ||
1568 | return perm; | |
1569 | } | |
1570 | ||
b68e418c SS |
1571 | #if CAP_LAST_CAP > 63 |
1572 | #error Fix SELinux to handle capabilities > 63. | |
1573 | #endif | |
1574 | ||
1da177e4 | 1575 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1576 | static int cred_has_capability(const struct cred *cred, |
c1a85a00 | 1577 | int cap, unsigned int opts, bool initns) |
1da177e4 | 1578 | { |
2bf49690 | 1579 | struct common_audit_data ad; |
06112163 | 1580 | struct av_decision avd; |
b68e418c | 1581 | u16 sclass; |
3699c53c | 1582 | u32 sid = cred_sid(cred); |
b68e418c | 1583 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1584 | int rc; |
1da177e4 | 1585 | |
50c205f5 | 1586 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1587 | ad.u.cap = cap; |
1588 | ||
b68e418c SS |
1589 | switch (CAP_TO_INDEX(cap)) { |
1590 | case 0: | |
8e4ff6f2 | 1591 | sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; |
b68e418c SS |
1592 | break; |
1593 | case 1: | |
8e4ff6f2 | 1594 | sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; |
b68e418c SS |
1595 | break; |
1596 | default: | |
c103a91e | 1597 | pr_err("SELinux: out of range capability %d\n", cap); |
b68e418c | 1598 | BUG(); |
a35c6c83 | 1599 | return -EINVAL; |
b68e418c | 1600 | } |
06112163 | 1601 | |
6b6bc620 SS |
1602 | rc = avc_has_perm_noaudit(&selinux_state, |
1603 | sid, sid, sclass, av, 0, &avd); | |
c1a85a00 | 1604 | if (!(opts & CAP_OPT_NOAUDIT)) { |
6b6bc620 | 1605 | int rc2 = avc_audit(&selinux_state, |
d99cf13f | 1606 | sid, sid, sclass, av, &avd, rc, &ad); |
9ade0cf4 EP |
1607 | if (rc2) |
1608 | return rc2; | |
1609 | } | |
06112163 | 1610 | return rc; |
1da177e4 LT |
1611 | } |
1612 | ||
1da177e4 LT |
1613 | /* Check whether a task has a particular permission to an inode. |
1614 | The 'adp' parameter is optional and allows other audit | |
1615 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1616 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1617 | struct inode *inode, |
1618 | u32 perms, | |
19e49834 | 1619 | struct common_audit_data *adp) |
1da177e4 | 1620 | { |
1da177e4 | 1621 | struct inode_security_struct *isec; |
275bb41e | 1622 | u32 sid; |
1da177e4 | 1623 | |
e0e81739 DH |
1624 | validate_creds(cred); |
1625 | ||
828dfe1d | 1626 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1627 | return 0; |
1628 | ||
88e67f3b | 1629 | sid = cred_sid(cred); |
80788c22 | 1630 | isec = selinux_inode(inode); |
1da177e4 | 1631 | |
6b6bc620 SS |
1632 | return avc_has_perm(&selinux_state, |
1633 | sid, isec->sid, isec->sclass, perms, adp); | |
1da177e4 LT |
1634 | } |
1635 | ||
1636 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1637 | the dentry to help the auditing code to more easily generate the | |
1638 | pathname if needed. */ | |
88e67f3b | 1639 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1640 | struct dentry *dentry, |
1641 | u32 av) | |
1642 | { | |
c6f493d6 | 1643 | struct inode *inode = d_backing_inode(dentry); |
2bf49690 | 1644 | struct common_audit_data ad; |
88e67f3b | 1645 | |
50c205f5 | 1646 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1647 | ad.u.dentry = dentry; |
5d226df4 | 1648 | __inode_security_revalidate(inode, dentry, true); |
19e49834 | 1649 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1650 | } |
1651 | ||
1652 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1653 | the path to help the auditing code to more easily generate the | |
1654 | pathname if needed. */ | |
1655 | static inline int path_has_perm(const struct cred *cred, | |
3f7036a0 | 1656 | const struct path *path, |
2875fa00 EP |
1657 | u32 av) |
1658 | { | |
c6f493d6 | 1659 | struct inode *inode = d_backing_inode(path->dentry); |
2875fa00 EP |
1660 | struct common_audit_data ad; |
1661 | ||
50c205f5 | 1662 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1663 | ad.u.path = *path; |
5d226df4 | 1664 | __inode_security_revalidate(inode, path->dentry, true); |
19e49834 | 1665 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1666 | } |
1667 | ||
13f8e981 DH |
1668 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1669 | static inline int file_path_has_perm(const struct cred *cred, | |
1670 | struct file *file, | |
1671 | u32 av) | |
1672 | { | |
1673 | struct common_audit_data ad; | |
1674 | ||
43af5de7 VG |
1675 | ad.type = LSM_AUDIT_DATA_FILE; |
1676 | ad.u.file = file; | |
19e49834 | 1677 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1678 | } |
1679 | ||
f66e448c CF |
1680 | #ifdef CONFIG_BPF_SYSCALL |
1681 | static int bpf_fd_pass(struct file *file, u32 sid); | |
1682 | #endif | |
1683 | ||
1da177e4 LT |
1684 | /* Check whether a task can use an open file descriptor to |
1685 | access an inode in a given way. Check access to the | |
1686 | descriptor itself, and then use dentry_has_perm to | |
1687 | check a particular permission to the file. | |
1688 | Access to the descriptor is implicitly granted if it | |
1689 | has the same SID as the process. If av is zero, then | |
1690 | access to the file is not checked, e.g. for cases | |
1691 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1692 | static int file_has_perm(const struct cred *cred, |
1693 | struct file *file, | |
1694 | u32 av) | |
1da177e4 | 1695 | { |
bb6c6b02 | 1696 | struct file_security_struct *fsec = selinux_file(file); |
496ad9aa | 1697 | struct inode *inode = file_inode(file); |
2bf49690 | 1698 | struct common_audit_data ad; |
88e67f3b | 1699 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1700 | int rc; |
1701 | ||
43af5de7 VG |
1702 | ad.type = LSM_AUDIT_DATA_FILE; |
1703 | ad.u.file = file; | |
1da177e4 | 1704 | |
275bb41e | 1705 | if (sid != fsec->sid) { |
6b6bc620 SS |
1706 | rc = avc_has_perm(&selinux_state, |
1707 | sid, fsec->sid, | |
1da177e4 LT |
1708 | SECCLASS_FD, |
1709 | FD__USE, | |
1710 | &ad); | |
1711 | if (rc) | |
88e67f3b | 1712 | goto out; |
1da177e4 LT |
1713 | } |
1714 | ||
f66e448c CF |
1715 | #ifdef CONFIG_BPF_SYSCALL |
1716 | rc = bpf_fd_pass(file, cred_sid(cred)); | |
1717 | if (rc) | |
1718 | return rc; | |
1719 | #endif | |
1720 | ||
1da177e4 | 1721 | /* av is zero if only checking access to the descriptor. */ |
88e67f3b | 1722 | rc = 0; |
1da177e4 | 1723 | if (av) |
19e49834 | 1724 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1725 | |
88e67f3b DH |
1726 | out: |
1727 | return rc; | |
1da177e4 LT |
1728 | } |
1729 | ||
c3c188b2 DH |
1730 | /* |
1731 | * Determine the label for an inode that might be unioned. | |
1732 | */ | |
c957f6df VG |
1733 | static int |
1734 | selinux_determine_inode_label(const struct task_security_struct *tsec, | |
1735 | struct inode *dir, | |
1736 | const struct qstr *name, u16 tclass, | |
1737 | u32 *_new_isid) | |
c3c188b2 | 1738 | { |
1aea7808 CS |
1739 | const struct superblock_security_struct *sbsec = |
1740 | selinux_superblock(dir->i_sb); | |
c3c188b2 DH |
1741 | |
1742 | if ((sbsec->flags & SE_SBINITIALIZED) && | |
1743 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { | |
1744 | *_new_isid = sbsec->mntpoint_sid; | |
1745 | } else if ((sbsec->flags & SBLABEL_MNT) && | |
1746 | tsec->create_sid) { | |
1747 | *_new_isid = tsec->create_sid; | |
1748 | } else { | |
20cdef8d | 1749 | const struct inode_security_struct *dsec = inode_security(dir); |
aa8e712c SS |
1750 | return security_transition_sid(&selinux_state, tsec->sid, |
1751 | dsec->sid, tclass, | |
c3c188b2 DH |
1752 | name, _new_isid); |
1753 | } | |
1754 | ||
1755 | return 0; | |
1756 | } | |
1757 | ||
1da177e4 LT |
1758 | /* Check whether a task can create a file. */ |
1759 | static int may_create(struct inode *dir, | |
1760 | struct dentry *dentry, | |
1761 | u16 tclass) | |
1762 | { | |
0c6cfa62 | 1763 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
1da177e4 LT |
1764 | struct inode_security_struct *dsec; |
1765 | struct superblock_security_struct *sbsec; | |
275bb41e | 1766 | u32 sid, newsid; |
2bf49690 | 1767 | struct common_audit_data ad; |
1da177e4 LT |
1768 | int rc; |
1769 | ||
83da53c5 | 1770 | dsec = inode_security(dir); |
1aea7808 | 1771 | sbsec = selinux_superblock(dir->i_sb); |
1da177e4 | 1772 | |
275bb41e | 1773 | sid = tsec->sid; |
275bb41e | 1774 | |
50c205f5 | 1775 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1776 | ad.u.dentry = dentry; |
1da177e4 | 1777 | |
6b6bc620 SS |
1778 | rc = avc_has_perm(&selinux_state, |
1779 | sid, dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
1780 | DIR__ADD_NAME | DIR__SEARCH, |
1781 | &ad); | |
1782 | if (rc) | |
1783 | return rc; | |
1784 | ||
210a2928 YG |
1785 | rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass, |
1786 | &newsid); | |
c3c188b2 DH |
1787 | if (rc) |
1788 | return rc; | |
1da177e4 | 1789 | |
6b6bc620 SS |
1790 | rc = avc_has_perm(&selinux_state, |
1791 | sid, newsid, tclass, FILE__CREATE, &ad); | |
1da177e4 LT |
1792 | if (rc) |
1793 | return rc; | |
1794 | ||
6b6bc620 SS |
1795 | return avc_has_perm(&selinux_state, |
1796 | newsid, sbsec->sid, | |
1da177e4 LT |
1797 | SECCLASS_FILESYSTEM, |
1798 | FILESYSTEM__ASSOCIATE, &ad); | |
1799 | } | |
1800 | ||
828dfe1d EP |
1801 | #define MAY_LINK 0 |
1802 | #define MAY_UNLINK 1 | |
1803 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1804 | |
1805 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1806 | static int may_link(struct inode *dir, | |
1807 | struct dentry *dentry, | |
1808 | int kind) | |
1809 | ||
1810 | { | |
1da177e4 | 1811 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 1812 | struct common_audit_data ad; |
275bb41e | 1813 | u32 sid = current_sid(); |
1da177e4 LT |
1814 | u32 av; |
1815 | int rc; | |
1816 | ||
83da53c5 AG |
1817 | dsec = inode_security(dir); |
1818 | isec = backing_inode_security(dentry); | |
1da177e4 | 1819 | |
50c205f5 | 1820 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1821 | ad.u.dentry = dentry; |
1da177e4 LT |
1822 | |
1823 | av = DIR__SEARCH; | |
1824 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
6b6bc620 SS |
1825 | rc = avc_has_perm(&selinux_state, |
1826 | sid, dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
1827 | if (rc) |
1828 | return rc; | |
1829 | ||
1830 | switch (kind) { | |
1831 | case MAY_LINK: | |
1832 | av = FILE__LINK; | |
1833 | break; | |
1834 | case MAY_UNLINK: | |
1835 | av = FILE__UNLINK; | |
1836 | break; | |
1837 | case MAY_RMDIR: | |
1838 | av = DIR__RMDIR; | |
1839 | break; | |
1840 | default: | |
c103a91e | 1841 | pr_warn("SELinux: %s: unrecognized kind %d\n", |
744ba35e | 1842 | __func__, kind); |
1da177e4 LT |
1843 | return 0; |
1844 | } | |
1845 | ||
6b6bc620 SS |
1846 | rc = avc_has_perm(&selinux_state, |
1847 | sid, isec->sid, isec->sclass, av, &ad); | |
1da177e4 LT |
1848 | return rc; |
1849 | } | |
1850 | ||
1851 | static inline int may_rename(struct inode *old_dir, | |
1852 | struct dentry *old_dentry, | |
1853 | struct inode *new_dir, | |
1854 | struct dentry *new_dentry) | |
1855 | { | |
1da177e4 | 1856 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 1857 | struct common_audit_data ad; |
275bb41e | 1858 | u32 sid = current_sid(); |
1da177e4 LT |
1859 | u32 av; |
1860 | int old_is_dir, new_is_dir; | |
1861 | int rc; | |
1862 | ||
83da53c5 AG |
1863 | old_dsec = inode_security(old_dir); |
1864 | old_isec = backing_inode_security(old_dentry); | |
e36cb0b8 | 1865 | old_is_dir = d_is_dir(old_dentry); |
83da53c5 | 1866 | new_dsec = inode_security(new_dir); |
1da177e4 | 1867 | |
50c205f5 | 1868 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 1869 | |
a269434d | 1870 | ad.u.dentry = old_dentry; |
6b6bc620 SS |
1871 | rc = avc_has_perm(&selinux_state, |
1872 | sid, old_dsec->sid, SECCLASS_DIR, | |
1da177e4 LT |
1873 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
1874 | if (rc) | |
1875 | return rc; | |
6b6bc620 SS |
1876 | rc = avc_has_perm(&selinux_state, |
1877 | sid, old_isec->sid, | |
1da177e4 LT |
1878 | old_isec->sclass, FILE__RENAME, &ad); |
1879 | if (rc) | |
1880 | return rc; | |
1881 | if (old_is_dir && new_dir != old_dir) { | |
6b6bc620 SS |
1882 | rc = avc_has_perm(&selinux_state, |
1883 | sid, old_isec->sid, | |
1da177e4 LT |
1884 | old_isec->sclass, DIR__REPARENT, &ad); |
1885 | if (rc) | |
1886 | return rc; | |
1887 | } | |
1888 | ||
a269434d | 1889 | ad.u.dentry = new_dentry; |
1da177e4 | 1890 | av = DIR__ADD_NAME | DIR__SEARCH; |
2c616d4d | 1891 | if (d_is_positive(new_dentry)) |
1da177e4 | 1892 | av |= DIR__REMOVE_NAME; |
6b6bc620 SS |
1893 | rc = avc_has_perm(&selinux_state, |
1894 | sid, new_dsec->sid, SECCLASS_DIR, av, &ad); | |
1da177e4 LT |
1895 | if (rc) |
1896 | return rc; | |
2c616d4d | 1897 | if (d_is_positive(new_dentry)) { |
83da53c5 | 1898 | new_isec = backing_inode_security(new_dentry); |
e36cb0b8 | 1899 | new_is_dir = d_is_dir(new_dentry); |
6b6bc620 SS |
1900 | rc = avc_has_perm(&selinux_state, |
1901 | sid, new_isec->sid, | |
1da177e4 LT |
1902 | new_isec->sclass, |
1903 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1904 | if (rc) | |
1905 | return rc; | |
1906 | } | |
1907 | ||
1908 | return 0; | |
1909 | } | |
1910 | ||
1911 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 1912 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
1913 | struct super_block *sb, |
1914 | u32 perms, | |
2bf49690 | 1915 | struct common_audit_data *ad) |
1da177e4 | 1916 | { |
1da177e4 | 1917 | struct superblock_security_struct *sbsec; |
88e67f3b | 1918 | u32 sid = cred_sid(cred); |
1da177e4 | 1919 | |
1aea7808 | 1920 | sbsec = selinux_superblock(sb); |
6b6bc620 SS |
1921 | return avc_has_perm(&selinux_state, |
1922 | sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); | |
1da177e4 LT |
1923 | } |
1924 | ||
1925 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1926 | static inline u32 file_mask_to_av(int mode, int mask) | |
1927 | { | |
1928 | u32 av = 0; | |
1929 | ||
dba19c60 | 1930 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
1931 | if (mask & MAY_EXEC) |
1932 | av |= FILE__EXECUTE; | |
1933 | if (mask & MAY_READ) | |
1934 | av |= FILE__READ; | |
1935 | ||
1936 | if (mask & MAY_APPEND) | |
1937 | av |= FILE__APPEND; | |
1938 | else if (mask & MAY_WRITE) | |
1939 | av |= FILE__WRITE; | |
1940 | ||
1941 | } else { | |
1942 | if (mask & MAY_EXEC) | |
1943 | av |= DIR__SEARCH; | |
1944 | if (mask & MAY_WRITE) | |
1945 | av |= DIR__WRITE; | |
1946 | if (mask & MAY_READ) | |
1947 | av |= DIR__READ; | |
1948 | } | |
1949 | ||
1950 | return av; | |
1951 | } | |
1952 | ||
8b6a5a37 EP |
1953 | /* Convert a Linux file to an access vector. */ |
1954 | static inline u32 file_to_av(struct file *file) | |
1955 | { | |
1956 | u32 av = 0; | |
1957 | ||
1958 | if (file->f_mode & FMODE_READ) | |
1959 | av |= FILE__READ; | |
1960 | if (file->f_mode & FMODE_WRITE) { | |
1961 | if (file->f_flags & O_APPEND) | |
1962 | av |= FILE__APPEND; | |
1963 | else | |
1964 | av |= FILE__WRITE; | |
1965 | } | |
1966 | if (!av) { | |
1967 | /* | |
1968 | * Special file opened with flags 3 for ioctl-only use. | |
1969 | */ | |
1970 | av = FILE__IOCTL; | |
1971 | } | |
1972 | ||
1973 | return av; | |
1974 | } | |
1975 | ||
b0c636b9 | 1976 | /* |
c76a2f9e | 1977 | * Convert a file to an access vector and include the correct |
b0c636b9 EP |
1978 | * open permission. |
1979 | */ | |
8b6a5a37 | 1980 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 1981 | { |
8b6a5a37 | 1982 | u32 av = file_to_av(file); |
ccb54478 | 1983 | struct inode *inode = file_inode(file); |
b0c636b9 | 1984 | |
aa8e712c SS |
1985 | if (selinux_policycap_openperm() && |
1986 | inode->i_sb->s_magic != SOCKFS_MAGIC) | |
49b7b8de EP |
1987 | av |= FILE__OPEN; |
1988 | ||
b0c636b9 EP |
1989 | return av; |
1990 | } | |
1991 | ||
1da177e4 LT |
1992 | /* Hook functions begin here. */ |
1993 | ||
52f88693 | 1994 | static int selinux_binder_set_context_mgr(const struct cred *mgr) |
79af7307 | 1995 | { |
6b6bc620 | 1996 | return avc_has_perm(&selinux_state, |
52f88693 | 1997 | current_sid(), cred_sid(mgr), SECCLASS_BINDER, |
79af7307 SS |
1998 | BINDER__SET_CONTEXT_MGR, NULL); |
1999 | } | |
2000 | ||
52f88693 TK |
2001 | static int selinux_binder_transaction(const struct cred *from, |
2002 | const struct cred *to) | |
79af7307 SS |
2003 | { |
2004 | u32 mysid = current_sid(); | |
52f88693 TK |
2005 | u32 fromsid = cred_sid(from); |
2006 | u32 tosid = cred_sid(to); | |
79af7307 SS |
2007 | int rc; |
2008 | ||
2009 | if (mysid != fromsid) { | |
6b6bc620 SS |
2010 | rc = avc_has_perm(&selinux_state, |
2011 | mysid, fromsid, SECCLASS_BINDER, | |
79af7307 SS |
2012 | BINDER__IMPERSONATE, NULL); |
2013 | if (rc) | |
2014 | return rc; | |
2015 | } | |
2016 | ||
52f88693 | 2017 | return avc_has_perm(&selinux_state, fromsid, tosid, |
eb1231f7 | 2018 | SECCLASS_BINDER, BINDER__CALL, NULL); |
79af7307 SS |
2019 | } |
2020 | ||
52f88693 TK |
2021 | static int selinux_binder_transfer_binder(const struct cred *from, |
2022 | const struct cred *to) | |
79af7307 | 2023 | { |
6b6bc620 | 2024 | return avc_has_perm(&selinux_state, |
52f88693 | 2025 | cred_sid(from), cred_sid(to), |
eb1231f7 | 2026 | SECCLASS_BINDER, BINDER__TRANSFER, |
79af7307 SS |
2027 | NULL); |
2028 | } | |
2029 | ||
52f88693 TK |
2030 | static int selinux_binder_transfer_file(const struct cred *from, |
2031 | const struct cred *to, | |
79af7307 SS |
2032 | struct file *file) |
2033 | { | |
52f88693 | 2034 | u32 sid = cred_sid(to); |
bb6c6b02 | 2035 | struct file_security_struct *fsec = selinux_file(file); |
83da53c5 | 2036 | struct dentry *dentry = file->f_path.dentry; |
20cdef8d | 2037 | struct inode_security_struct *isec; |
79af7307 SS |
2038 | struct common_audit_data ad; |
2039 | int rc; | |
2040 | ||
2041 | ad.type = LSM_AUDIT_DATA_PATH; | |
2042 | ad.u.path = file->f_path; | |
2043 | ||
2044 | if (sid != fsec->sid) { | |
6b6bc620 SS |
2045 | rc = avc_has_perm(&selinux_state, |
2046 | sid, fsec->sid, | |
79af7307 SS |
2047 | SECCLASS_FD, |
2048 | FD__USE, | |
2049 | &ad); | |
2050 | if (rc) | |
2051 | return rc; | |
2052 | } | |
2053 | ||
f66e448c CF |
2054 | #ifdef CONFIG_BPF_SYSCALL |
2055 | rc = bpf_fd_pass(file, sid); | |
2056 | if (rc) | |
2057 | return rc; | |
2058 | #endif | |
2059 | ||
83da53c5 | 2060 | if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
79af7307 SS |
2061 | return 0; |
2062 | ||
20cdef8d | 2063 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
2064 | return avc_has_perm(&selinux_state, |
2065 | sid, isec->sid, isec->sclass, file_to_av(file), | |
79af7307 SS |
2066 | &ad); |
2067 | } | |
2068 | ||
9e48858f | 2069 | static int selinux_ptrace_access_check(struct task_struct *child, |
eb1231f7 | 2070 | unsigned int mode) |
1da177e4 | 2071 | { |
be0554c9 | 2072 | u32 sid = current_sid(); |
eb1231f7 | 2073 | u32 csid = task_sid_obj(child); |
be0554c9 SS |
2074 | |
2075 | if (mode & PTRACE_MODE_READ) | |
6b6bc620 SS |
2076 | return avc_has_perm(&selinux_state, |
2077 | sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 | 2078 | |
6b6bc620 SS |
2079 | return avc_has_perm(&selinux_state, |
2080 | sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); | |
5cd9c58f DH |
2081 | } |
2082 | ||
2083 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
2084 | { | |
6b6bc620 | 2085 | return avc_has_perm(&selinux_state, |
a3727a8b | 2086 | task_sid_obj(parent), task_sid_obj(current), |
eb1231f7 | 2087 | SECCLASS_PROCESS, PROCESS__PTRACE, NULL); |
1da177e4 LT |
2088 | } |
2089 | ||
2090 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 2091 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 | 2092 | { |
6b6bc620 | 2093 | return avc_has_perm(&selinux_state, |
eb1231f7 | 2094 | current_sid(), task_sid_obj(target), SECCLASS_PROCESS, |
be0554c9 | 2095 | PROCESS__GETCAP, NULL); |
1da177e4 LT |
2096 | } |
2097 | ||
d84f4f99 DH |
2098 | static int selinux_capset(struct cred *new, const struct cred *old, |
2099 | const kernel_cap_t *effective, | |
2100 | const kernel_cap_t *inheritable, | |
2101 | const kernel_cap_t *permitted) | |
1da177e4 | 2102 | { |
6b6bc620 SS |
2103 | return avc_has_perm(&selinux_state, |
2104 | cred_sid(old), cred_sid(new), SECCLASS_PROCESS, | |
be0554c9 | 2105 | PROCESS__SETCAP, NULL); |
1da177e4 LT |
2106 | } |
2107 | ||
5626d3e8 JM |
2108 | /* |
2109 | * (This comment used to live with the selinux_task_setuid hook, | |
2110 | * which was removed). | |
2111 | * | |
2112 | * Since setuid only affects the current process, and since the SELinux | |
2113 | * controls are not based on the Linux identity attributes, SELinux does not | |
2114 | * need to control this operation. However, SELinux does control the use of | |
2115 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
2116 | */ | |
2117 | ||
6a9de491 | 2118 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
c1a85a00 | 2119 | int cap, unsigned int opts) |
1da177e4 | 2120 | { |
c1a85a00 | 2121 | return cred_has_capability(cred, cap, opts, ns == &init_user_ns); |
1da177e4 LT |
2122 | } |
2123 | ||
1da177e4 LT |
2124 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
2125 | { | |
88e67f3b | 2126 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2127 | int rc = 0; |
2128 | ||
2129 | if (!sb) | |
2130 | return 0; | |
2131 | ||
2132 | switch (cmds) { | |
828dfe1d EP |
2133 | case Q_SYNC: |
2134 | case Q_QUOTAON: | |
2135 | case Q_QUOTAOFF: | |
2136 | case Q_SETINFO: | |
2137 | case Q_SETQUOTA: | |
e4cfa05e RH |
2138 | case Q_XQUOTAOFF: |
2139 | case Q_XQUOTAON: | |
2140 | case Q_XSETQLIM: | |
88e67f3b | 2141 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
2142 | break; |
2143 | case Q_GETFMT: | |
2144 | case Q_GETINFO: | |
2145 | case Q_GETQUOTA: | |
e4cfa05e RH |
2146 | case Q_XGETQUOTA: |
2147 | case Q_XGETQSTAT: | |
2148 | case Q_XGETQSTATV: | |
2149 | case Q_XGETNEXTQUOTA: | |
88e67f3b | 2150 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
2151 | break; |
2152 | default: | |
2153 | rc = 0; /* let the kernel handle invalid cmds */ | |
2154 | break; | |
1da177e4 LT |
2155 | } |
2156 | return rc; | |
2157 | } | |
2158 | ||
2159 | static int selinux_quota_on(struct dentry *dentry) | |
2160 | { | |
88e67f3b DH |
2161 | const struct cred *cred = current_cred(); |
2162 | ||
2875fa00 | 2163 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
2164 | } |
2165 | ||
12b3052c | 2166 | static int selinux_syslog(int type) |
1da177e4 | 2167 | { |
1da177e4 | 2168 | switch (type) { |
d78ca3cd KC |
2169 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2170 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
6b6bc620 SS |
2171 | return avc_has_perm(&selinux_state, |
2172 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2173 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); |
d78ca3cd KC |
2174 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2175 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2176 | /* Set level of messages printed to console */ | |
2177 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
6b6bc620 SS |
2178 | return avc_has_perm(&selinux_state, |
2179 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 SS |
2180 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, |
2181 | NULL); | |
1da177e4 | 2182 | } |
be0554c9 | 2183 | /* All other syslog types */ |
6b6bc620 SS |
2184 | return avc_has_perm(&selinux_state, |
2185 | current_sid(), SECINITSID_KERNEL, | |
be0554c9 | 2186 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); |
1da177e4 LT |
2187 | } |
2188 | ||
2189 | /* | |
2190 | * Check that a process has enough memory to allocate a new virtual | |
2191 | * mapping. 0 means there is enough memory for the allocation to | |
2192 | * succeed and -ENOMEM implies there is not. | |
2193 | * | |
1da177e4 LT |
2194 | * Do not audit the selinux permission check, as this is applied to all |
2195 | * processes that allocate mappings. | |
2196 | */ | |
34b4e4aa | 2197 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2198 | { |
2199 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2200 | |
b1d9e6b0 | 2201 | rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, |
c1a85a00 | 2202 | CAP_OPT_NOAUDIT, true); |
1da177e4 LT |
2203 | if (rc == 0) |
2204 | cap_sys_admin = 1; | |
2205 | ||
b1d9e6b0 | 2206 | return cap_sys_admin; |
1da177e4 LT |
2207 | } |
2208 | ||
2209 | /* binprm security operations */ | |
2210 | ||
be0554c9 | 2211 | static u32 ptrace_parent_sid(void) |
0c6181cb PM |
2212 | { |
2213 | u32 sid = 0; | |
2214 | struct task_struct *tracer; | |
2215 | ||
2216 | rcu_read_lock(); | |
be0554c9 | 2217 | tracer = ptrace_parent(current); |
0c6181cb | 2218 | if (tracer) |
eb1231f7 | 2219 | sid = task_sid_obj(tracer); |
0c6181cb PM |
2220 | rcu_read_unlock(); |
2221 | ||
2222 | return sid; | |
2223 | } | |
2224 | ||
7b0d0b40 SS |
2225 | static int check_nnp_nosuid(const struct linux_binprm *bprm, |
2226 | const struct task_security_struct *old_tsec, | |
2227 | const struct task_security_struct *new_tsec) | |
2228 | { | |
2229 | int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); | |
380cf5ba | 2230 | int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); |
7b0d0b40 | 2231 | int rc; |
af63f419 | 2232 | u32 av; |
7b0d0b40 SS |
2233 | |
2234 | if (!nnp && !nosuid) | |
2235 | return 0; /* neither NNP nor nosuid */ | |
2236 | ||
2237 | if (new_tsec->sid == old_tsec->sid) | |
2238 | return 0; /* No change in credentials */ | |
2239 | ||
2240 | /* | |
af63f419 SS |
2241 | * If the policy enables the nnp_nosuid_transition policy capability, |
2242 | * then we permit transitions under NNP or nosuid if the | |
2243 | * policy allows the corresponding permission between | |
2244 | * the old and new contexts. | |
7b0d0b40 | 2245 | */ |
aa8e712c | 2246 | if (selinux_policycap_nnp_nosuid_transition()) { |
af63f419 | 2247 | av = 0; |
7b0d0b40 | 2248 | if (nnp) |
af63f419 SS |
2249 | av |= PROCESS2__NNP_TRANSITION; |
2250 | if (nosuid) | |
2251 | av |= PROCESS2__NOSUID_TRANSITION; | |
6b6bc620 SS |
2252 | rc = avc_has_perm(&selinux_state, |
2253 | old_tsec->sid, new_tsec->sid, | |
af63f419 SS |
2254 | SECCLASS_PROCESS2, av, NULL); |
2255 | if (!rc) | |
2256 | return 0; | |
7b0d0b40 | 2257 | } |
af63f419 SS |
2258 | |
2259 | /* | |
2260 | * We also permit NNP or nosuid transitions to bounded SIDs, | |
2261 | * i.e. SIDs that are guaranteed to only be allowed a subset | |
2262 | * of the permissions of the current SID. | |
2263 | */ | |
aa8e712c SS |
2264 | rc = security_bounded_transition(&selinux_state, old_tsec->sid, |
2265 | new_tsec->sid); | |
af63f419 SS |
2266 | if (!rc) |
2267 | return 0; | |
2268 | ||
2269 | /* | |
2270 | * On failure, preserve the errno values for NNP vs nosuid. | |
2271 | * NNP: Operation not permitted for caller. | |
2272 | * nosuid: Permission denied to file. | |
2273 | */ | |
2274 | if (nnp) | |
2275 | return -EPERM; | |
2276 | return -EACCES; | |
7b0d0b40 SS |
2277 | } |
2278 | ||
b8bff599 | 2279 | static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm) |
1da177e4 | 2280 | { |
a6f76f23 DH |
2281 | const struct task_security_struct *old_tsec; |
2282 | struct task_security_struct *new_tsec; | |
1da177e4 | 2283 | struct inode_security_struct *isec; |
2bf49690 | 2284 | struct common_audit_data ad; |
496ad9aa | 2285 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2286 | int rc; |
2287 | ||
a6f76f23 DH |
2288 | /* SELinux context only depends on initial program or script and not |
2289 | * the script interpreter */ | |
1da177e4 | 2290 | |
0c6cfa62 CS |
2291 | old_tsec = selinux_cred(current_cred()); |
2292 | new_tsec = selinux_cred(bprm->cred); | |
83da53c5 | 2293 | isec = inode_security(inode); |
1da177e4 LT |
2294 | |
2295 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2296 | new_tsec->sid = old_tsec->sid; |
2297 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2298 | |
28eba5bf | 2299 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2300 | new_tsec->create_sid = 0; |
2301 | new_tsec->keycreate_sid = 0; | |
2302 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2303 | |
a6f76f23 DH |
2304 | if (old_tsec->exec_sid) { |
2305 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2306 | /* Reset exec SID on execve. */ |
a6f76f23 | 2307 | new_tsec->exec_sid = 0; |
259e5e6c | 2308 | |
7b0d0b40 SS |
2309 | /* Fail on NNP or nosuid if not an allowed transition. */ |
2310 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2311 | if (rc) | |
2312 | return rc; | |
1da177e4 LT |
2313 | } else { |
2314 | /* Check for a default transition on this program. */ | |
aa8e712c SS |
2315 | rc = security_transition_sid(&selinux_state, old_tsec->sid, |
2316 | isec->sid, SECCLASS_PROCESS, NULL, | |
652bb9b0 | 2317 | &new_tsec->sid); |
1da177e4 LT |
2318 | if (rc) |
2319 | return rc; | |
7b0d0b40 SS |
2320 | |
2321 | /* | |
2322 | * Fallback to old SID on NNP or nosuid if not an allowed | |
2323 | * transition. | |
2324 | */ | |
2325 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2326 | if (rc) | |
2327 | new_tsec->sid = old_tsec->sid; | |
1da177e4 LT |
2328 | } |
2329 | ||
43af5de7 VG |
2330 | ad.type = LSM_AUDIT_DATA_FILE; |
2331 | ad.u.file = bprm->file; | |
1da177e4 | 2332 | |
a6f76f23 | 2333 | if (new_tsec->sid == old_tsec->sid) { |
6b6bc620 SS |
2334 | rc = avc_has_perm(&selinux_state, |
2335 | old_tsec->sid, isec->sid, | |
1da177e4 LT |
2336 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2337 | if (rc) | |
2338 | return rc; | |
2339 | } else { | |
2340 | /* Check permissions for the transition. */ | |
6b6bc620 SS |
2341 | rc = avc_has_perm(&selinux_state, |
2342 | old_tsec->sid, new_tsec->sid, | |
1da177e4 LT |
2343 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2344 | if (rc) | |
2345 | return rc; | |
2346 | ||
6b6bc620 SS |
2347 | rc = avc_has_perm(&selinux_state, |
2348 | new_tsec->sid, isec->sid, | |
1da177e4 LT |
2349 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2350 | if (rc) | |
2351 | return rc; | |
2352 | ||
a6f76f23 DH |
2353 | /* Check for shared state */ |
2354 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
6b6bc620 SS |
2355 | rc = avc_has_perm(&selinux_state, |
2356 | old_tsec->sid, new_tsec->sid, | |
a6f76f23 DH |
2357 | SECCLASS_PROCESS, PROCESS__SHARE, |
2358 | NULL); | |
2359 | if (rc) | |
2360 | return -EPERM; | |
2361 | } | |
2362 | ||
2363 | /* Make sure that anyone attempting to ptrace over a task that | |
2364 | * changes its SID has the appropriate permit */ | |
9227dd2a | 2365 | if (bprm->unsafe & LSM_UNSAFE_PTRACE) { |
be0554c9 | 2366 | u32 ptsid = ptrace_parent_sid(); |
a6f76f23 | 2367 | if (ptsid != 0) { |
6b6bc620 SS |
2368 | rc = avc_has_perm(&selinux_state, |
2369 | ptsid, new_tsec->sid, | |
a6f76f23 DH |
2370 | SECCLASS_PROCESS, |
2371 | PROCESS__PTRACE, NULL); | |
2372 | if (rc) | |
2373 | return -EPERM; | |
2374 | } | |
2375 | } | |
1da177e4 | 2376 | |
a6f76f23 DH |
2377 | /* Clear any possibly unsafe personality bits on exec: */ |
2378 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
275bb41e | 2379 | |
1da177e4 LT |
2380 | /* Enable secure mode for SIDs transitions unless |
2381 | the noatsecure permission is granted between | |
2382 | the two SIDs, i.e. ahp returns 0. */ | |
6b6bc620 SS |
2383 | rc = avc_has_perm(&selinux_state, |
2384 | old_tsec->sid, new_tsec->sid, | |
62874c3a KC |
2385 | SECCLASS_PROCESS, PROCESS__NOATSECURE, |
2386 | NULL); | |
2387 | bprm->secureexec |= !!rc; | |
1da177e4 LT |
2388 | } |
2389 | ||
62874c3a | 2390 | return 0; |
1da177e4 LT |
2391 | } |
2392 | ||
c3c073f8 AV |
2393 | static int match_file(const void *p, struct file *file, unsigned fd) |
2394 | { | |
2395 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2396 | } | |
2397 | ||
1da177e4 | 2398 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2399 | static inline void flush_unauthorized_files(const struct cred *cred, |
2400 | struct files_struct *files) | |
1da177e4 | 2401 | { |
1da177e4 | 2402 | struct file *file, *devnull = NULL; |
b20c8122 | 2403 | struct tty_struct *tty; |
24ec839c | 2404 | int drop_tty = 0; |
c3c073f8 | 2405 | unsigned n; |
1da177e4 | 2406 | |
24ec839c | 2407 | tty = get_current_tty(); |
1da177e4 | 2408 | if (tty) { |
4a510969 | 2409 | spin_lock(&tty->files_lock); |
37dd0bd0 | 2410 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2411 | struct tty_file_private *file_priv; |
37dd0bd0 | 2412 | |
1da177e4 | 2413 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2414 | Use file_path_has_perm on the tty path directly |
2415 | rather than using file_has_perm, as this particular | |
2416 | open file may belong to another process and we are | |
2417 | only interested in the inode-based check here. */ | |
d996b62a NP |
2418 | file_priv = list_first_entry(&tty->tty_files, |
2419 | struct tty_file_private, list); | |
2420 | file = file_priv->file; | |
13f8e981 | 2421 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2422 | drop_tty = 1; |
1da177e4 | 2423 | } |
4a510969 | 2424 | spin_unlock(&tty->files_lock); |
452a00d2 | 2425 | tty_kref_put(tty); |
1da177e4 | 2426 | } |
98a27ba4 EB |
2427 | /* Reset controlling tty. */ |
2428 | if (drop_tty) | |
2429 | no_tty(); | |
1da177e4 LT |
2430 | |
2431 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2432 | n = iterate_fd(files, 0, match_file, cred); |
2433 | if (!n) /* none found? */ | |
2434 | return; | |
1da177e4 | 2435 | |
c3c073f8 | 2436 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2437 | if (IS_ERR(devnull)) |
2438 | devnull = NULL; | |
2439 | /* replace all the matching ones with this */ | |
2440 | do { | |
2441 | replace_fd(n - 1, devnull, 0); | |
2442 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2443 | if (devnull) | |
c3c073f8 | 2444 | fput(devnull); |
1da177e4 LT |
2445 | } |
2446 | ||
a6f76f23 DH |
2447 | /* |
2448 | * Prepare a process for imminent new credential changes due to exec | |
2449 | */ | |
2450 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2451 | { |
a6f76f23 DH |
2452 | struct task_security_struct *new_tsec; |
2453 | struct rlimit *rlim, *initrlim; | |
2454 | int rc, i; | |
d84f4f99 | 2455 | |
0c6cfa62 | 2456 | new_tsec = selinux_cred(bprm->cred); |
a6f76f23 DH |
2457 | if (new_tsec->sid == new_tsec->osid) |
2458 | return; | |
1da177e4 | 2459 | |
a6f76f23 DH |
2460 | /* Close files for which the new task SID is not authorized. */ |
2461 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2462 | |
a6f76f23 DH |
2463 | /* Always clear parent death signal on SID transitions. */ |
2464 | current->pdeath_signal = 0; | |
0356357c | 2465 | |
a6f76f23 DH |
2466 | /* Check whether the new SID can inherit resource limits from the old |
2467 | * SID. If not, reset all soft limits to the lower of the current | |
2468 | * task's hard limit and the init task's soft limit. | |
2469 | * | |
2470 | * Note that the setting of hard limits (even to lower them) can be | |
2471 | * controlled by the setrlimit check. The inclusion of the init task's | |
2472 | * soft limit into the computation is to avoid resetting soft limits | |
2473 | * higher than the default soft limit for cases where the default is | |
2474 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2475 | */ | |
6b6bc620 SS |
2476 | rc = avc_has_perm(&selinux_state, |
2477 | new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
a6f76f23 DH |
2478 | PROCESS__RLIMITINH, NULL); |
2479 | if (rc) { | |
eb2d55a3 ON |
2480 | /* protect against do_prlimit() */ |
2481 | task_lock(current); | |
a6f76f23 DH |
2482 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2483 | rlim = current->signal->rlim + i; | |
2484 | initrlim = init_task.signal->rlim + i; | |
2485 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2486 | } |
eb2d55a3 | 2487 | task_unlock(current); |
baa73d9e NP |
2488 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) |
2489 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2490 | } |
2491 | } | |
2492 | ||
2493 | /* | |
a6f76f23 DH |
2494 | * Clean up the process immediately after the installation of new credentials |
2495 | * due to exec | |
1da177e4 | 2496 | */ |
a6f76f23 | 2497 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2498 | { |
0c6cfa62 | 2499 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
a6f76f23 | 2500 | u32 osid, sid; |
ddbc7d06 | 2501 | int rc; |
1da177e4 | 2502 | |
a6f76f23 DH |
2503 | osid = tsec->osid; |
2504 | sid = tsec->sid; | |
2505 | ||
2506 | if (sid == osid) | |
1da177e4 LT |
2507 | return; |
2508 | ||
a6f76f23 DH |
2509 | /* Check whether the new SID can inherit signal state from the old SID. |
2510 | * If not, clear itimers to avoid subsequent signal generation and | |
2511 | * flush and unblock signals. | |
2512 | * | |
2513 | * This must occur _after_ the task SID has been updated so that any | |
2514 | * kill done after the flush will be checked against the new SID. | |
2515 | */ | |
6b6bc620 SS |
2516 | rc = avc_has_perm(&selinux_state, |
2517 | osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 | 2518 | if (rc) { |
ddbc7d06 AB |
2519 | clear_itimer(); |
2520 | ||
0e326df0 | 2521 | spin_lock_irq(&unrcu_pointer(current->sighand)->siglock); |
9e7c8f8c ON |
2522 | if (!fatal_signal_pending(current)) { |
2523 | flush_sigqueue(¤t->pending); | |
2524 | flush_sigqueue(¤t->signal->shared_pending); | |
3bcac026 DH |
2525 | flush_signal_handlers(current, 1); |
2526 | sigemptyset(¤t->blocked); | |
9e7c8f8c | 2527 | recalc_sigpending(); |
3bcac026 | 2528 | } |
0e326df0 | 2529 | spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock); |
1da177e4 LT |
2530 | } |
2531 | ||
a6f76f23 DH |
2532 | /* Wake up the parent if it is waiting so that it can recheck |
2533 | * wait permission to the new task SID. */ | |
ecd6de3c | 2534 | read_lock(&tasklist_lock); |
0e326df0 | 2535 | __wake_up_parent(current, unrcu_pointer(current->real_parent)); |
ecd6de3c | 2536 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2537 | } |
2538 | ||
2539 | /* superblock security operations */ | |
2540 | ||
2541 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2542 | { | |
1aea7808 | 2543 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
cb89e246 PM |
2544 | |
2545 | mutex_init(&sbsec->lock); | |
2546 | INIT_LIST_HEAD(&sbsec->isec_head); | |
2547 | spin_lock_init(&sbsec->isec_lock); | |
cb89e246 PM |
2548 | sbsec->sid = SECINITSID_UNLABELED; |
2549 | sbsec->def_sid = SECINITSID_FILE; | |
2550 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; | |
cb89e246 PM |
2551 | |
2552 | return 0; | |
1da177e4 LT |
2553 | } |
2554 | ||
99dbbb59 | 2555 | static inline int opt_len(const char *s) |
1da177e4 | 2556 | { |
99dbbb59 AV |
2557 | bool open_quote = false; |
2558 | int len; | |
2559 | char c; | |
1da177e4 | 2560 | |
99dbbb59 AV |
2561 | for (len = 0; (c = s[len]) != '\0'; len++) { |
2562 | if (c == '"') | |
2563 | open_quote = !open_quote; | |
2564 | if (c == ',' && !open_quote) | |
2565 | break; | |
3528a953 | 2566 | } |
99dbbb59 | 2567 | return len; |
3528a953 CO |
2568 | } |
2569 | ||
99dbbb59 | 2570 | static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) |
1da177e4 | 2571 | { |
99dbbb59 AV |
2572 | char *from = options; |
2573 | char *to = options; | |
2574 | bool first = true; | |
fec63753 | 2575 | int rc; |
1da177e4 | 2576 | |
99dbbb59 AV |
2577 | while (1) { |
2578 | int len = opt_len(from); | |
fec63753 | 2579 | int token; |
99dbbb59 | 2580 | char *arg = NULL; |
1da177e4 | 2581 | |
99dbbb59 | 2582 | token = match_opt_prefix(from, len, &arg); |
1da177e4 | 2583 | |
99dbbb59 AV |
2584 | if (token != Opt_error) { |
2585 | char *p, *q; | |
1da177e4 | 2586 | |
99dbbb59 AV |
2587 | /* strip quotes */ |
2588 | if (arg) { | |
2589 | for (p = q = arg; p < from + len; p++) { | |
2590 | char c = *p; | |
2591 | if (c != '"') | |
2592 | *q++ = c; | |
2593 | } | |
2594 | arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); | |
fec63753 GZ |
2595 | if (!arg) { |
2596 | rc = -ENOMEM; | |
2597 | goto free_opt; | |
2598 | } | |
99dbbb59 AV |
2599 | } |
2600 | rc = selinux_add_opt(token, arg, mnt_opts); | |
cad140d0 CG |
2601 | kfree(arg); |
2602 | arg = NULL; | |
99dbbb59 | 2603 | if (unlikely(rc)) { |
fec63753 | 2604 | goto free_opt; |
99dbbb59 AV |
2605 | } |
2606 | } else { | |
2607 | if (!first) { // copy with preceding comma | |
2608 | from--; | |
2609 | len++; | |
2610 | } | |
2611 | if (to != from) | |
2612 | memmove(to, from, len); | |
2613 | to += len; | |
2614 | first = false; | |
1da177e4 | 2615 | } |
99dbbb59 AV |
2616 | if (!from[len]) |
2617 | break; | |
2618 | from += len + 1; | |
2619 | } | |
2620 | *to = '\0'; | |
2621 | return 0; | |
fec63753 GZ |
2622 | |
2623 | free_opt: | |
2624 | if (*mnt_opts) { | |
2625 | selinux_free_mnt_opts(*mnt_opts); | |
2626 | *mnt_opts = NULL; | |
2627 | } | |
2628 | return rc; | |
1da177e4 LT |
2629 | } |
2630 | ||
69c4a42d OK |
2631 | static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts) |
2632 | { | |
2633 | struct selinux_mnt_opts *opts = mnt_opts; | |
0266c25e | 2634 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
69c4a42d OK |
2635 | |
2636 | /* | |
2637 | * Superblock not initialized (i.e. no options) - reject if any | |
2638 | * options specified, otherwise accept. | |
2639 | */ | |
2640 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2641 | return opts ? 1 : 0; | |
2642 | ||
2643 | /* | |
2644 | * Superblock initialized and no options specified - reject if | |
2645 | * superblock has any options set, otherwise accept. | |
2646 | */ | |
2647 | if (!opts) | |
2648 | return (sbsec->flags & SE_MNTMASK) ? 1 : 0; | |
2649 | ||
70f4169a OM |
2650 | if (opts->fscontext_sid) { |
2651 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
2652 | opts->fscontext_sid)) | |
69c4a42d OK |
2653 | return 1; |
2654 | } | |
70f4169a OM |
2655 | if (opts->context_sid) { |
2656 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
2657 | opts->context_sid)) | |
69c4a42d OK |
2658 | return 1; |
2659 | } | |
70f4169a OM |
2660 | if (opts->rootcontext_sid) { |
2661 | struct inode_security_struct *root_isec; | |
b8b87fd9 | 2662 | |
70f4169a OM |
2663 | root_isec = backing_inode_security(sb->s_root); |
2664 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
2665 | opts->rootcontext_sid)) | |
69c4a42d | 2666 | return 1; |
70f4169a OM |
2667 | } |
2668 | if (opts->defcontext_sid) { | |
2669 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
2670 | opts->defcontext_sid)) | |
69c4a42d OK |
2671 | return 1; |
2672 | } | |
2673 | return 0; | |
2674 | } | |
2675 | ||
204cc0cc | 2676 | static int selinux_sb_remount(struct super_block *sb, void *mnt_opts) |
026eb167 | 2677 | { |
bd323655 | 2678 | struct selinux_mnt_opts *opts = mnt_opts; |
1aea7808 | 2679 | struct superblock_security_struct *sbsec = selinux_superblock(sb); |
026eb167 EP |
2680 | |
2681 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2682 | return 0; | |
2683 | ||
204cc0cc | 2684 | if (!opts) |
026eb167 EP |
2685 | return 0; |
2686 | ||
70f4169a | 2687 | if (opts->fscontext_sid) { |
6bc1968c SM |
2688 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, |
2689 | opts->fscontext_sid)) | |
bd323655 | 2690 | goto out_bad_option; |
026eb167 | 2691 | } |
70f4169a | 2692 | if (opts->context_sid) { |
6bc1968c SM |
2693 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, |
2694 | opts->context_sid)) | |
bd323655 AV |
2695 | goto out_bad_option; |
2696 | } | |
70f4169a | 2697 | if (opts->rootcontext_sid) { |
bd323655 AV |
2698 | struct inode_security_struct *root_isec; |
2699 | root_isec = backing_inode_security(sb->s_root); | |
6bc1968c SM |
2700 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, |
2701 | opts->rootcontext_sid)) | |
bd323655 AV |
2702 | goto out_bad_option; |
2703 | } | |
70f4169a | 2704 | if (opts->defcontext_sid) { |
6bc1968c SM |
2705 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, |
2706 | opts->defcontext_sid)) | |
bd323655 | 2707 | goto out_bad_option; |
026eb167 | 2708 | } |
c039bc3c | 2709 | return 0; |
026eb167 | 2710 | |
026eb167 | 2711 | out_bad_option: |
c103a91e | 2712 | pr_warn("SELinux: unable to change security options " |
29b1deb2 LT |
2713 | "during remount (dev %s, type=%s)\n", sb->s_id, |
2714 | sb->s_type->name); | |
c039bc3c | 2715 | return -EINVAL; |
026eb167 EP |
2716 | } |
2717 | ||
a10d7c22 | 2718 | static int selinux_sb_kern_mount(struct super_block *sb) |
1da177e4 | 2719 | { |
88e67f3b | 2720 | const struct cred *cred = current_cred(); |
2bf49690 | 2721 | struct common_audit_data ad; |
74192246 | 2722 | |
50c205f5 | 2723 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2724 | ad.u.dentry = sb->s_root; |
88e67f3b | 2725 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2726 | } |
2727 | ||
726c3342 | 2728 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2729 | { |
88e67f3b | 2730 | const struct cred *cred = current_cred(); |
2bf49690 | 2731 | struct common_audit_data ad; |
1da177e4 | 2732 | |
50c205f5 | 2733 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2734 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2735 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2736 | } |
2737 | ||
808d4e3c | 2738 | static int selinux_mount(const char *dev_name, |
8a04c43b | 2739 | const struct path *path, |
808d4e3c | 2740 | const char *type, |
828dfe1d EP |
2741 | unsigned long flags, |
2742 | void *data) | |
1da177e4 | 2743 | { |
88e67f3b | 2744 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2745 | |
2746 | if (flags & MS_REMOUNT) | |
d8c9584e | 2747 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2748 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2749 | else |
2875fa00 | 2750 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2751 | } |
2752 | ||
98aa0034 SS |
2753 | static int selinux_move_mount(const struct path *from_path, |
2754 | const struct path *to_path) | |
2755 | { | |
2756 | const struct cred *cred = current_cred(); | |
2757 | ||
2758 | return path_has_perm(cred, to_path, FILE__MOUNTON); | |
2759 | } | |
2760 | ||
1da177e4 LT |
2761 | static int selinux_umount(struct vfsmount *mnt, int flags) |
2762 | { | |
88e67f3b | 2763 | const struct cred *cred = current_cred(); |
1da177e4 | 2764 | |
88e67f3b | 2765 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2766 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2767 | } |
2768 | ||
0b52075e AV |
2769 | static int selinux_fs_context_dup(struct fs_context *fc, |
2770 | struct fs_context *src_fc) | |
2771 | { | |
2772 | const struct selinux_mnt_opts *src = src_fc->security; | |
0b52075e AV |
2773 | |
2774 | if (!src) | |
2775 | return 0; | |
2776 | ||
70f4169a OM |
2777 | fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL); |
2778 | return fc->security ? 0 : -ENOMEM; | |
0b52075e AV |
2779 | } |
2780 | ||
d7167b14 | 2781 | static const struct fs_parameter_spec selinux_fs_parameters[] = { |
442155c1 DH |
2782 | fsparam_string(CONTEXT_STR, Opt_context), |
2783 | fsparam_string(DEFCONTEXT_STR, Opt_defcontext), | |
2784 | fsparam_string(FSCONTEXT_STR, Opt_fscontext), | |
2785 | fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext), | |
2786 | fsparam_flag (SECLABEL_STR, Opt_seclabel), | |
2787 | {} | |
2788 | }; | |
2789 | ||
442155c1 DH |
2790 | static int selinux_fs_context_parse_param(struct fs_context *fc, |
2791 | struct fs_parameter *param) | |
2792 | { | |
2793 | struct fs_parse_result result; | |
cad140d0 | 2794 | int opt; |
442155c1 | 2795 | |
d7167b14 | 2796 | opt = fs_parse(fc, selinux_fs_parameters, param, &result); |
442155c1 DH |
2797 | if (opt < 0) |
2798 | return opt; | |
2799 | ||
cad140d0 | 2800 | return selinux_add_opt(opt, param->string, &fc->security); |
442155c1 DH |
2801 | } |
2802 | ||
1da177e4 LT |
2803 | /* inode security operations */ |
2804 | ||
2805 | static int selinux_inode_alloc_security(struct inode *inode) | |
2806 | { | |
cb89e246 PM |
2807 | struct inode_security_struct *isec = selinux_inode(inode); |
2808 | u32 sid = current_sid(); | |
2809 | ||
2810 | spin_lock_init(&isec->lock); | |
2811 | INIT_LIST_HEAD(&isec->list); | |
2812 | isec->inode = inode; | |
2813 | isec->sid = SECINITSID_UNLABELED; | |
2814 | isec->sclass = SECCLASS_FILE; | |
2815 | isec->task_sid = sid; | |
2816 | isec->initialized = LABEL_INVALID; | |
2817 | ||
2818 | return 0; | |
1da177e4 LT |
2819 | } |
2820 | ||
2821 | static void selinux_inode_free_security(struct inode *inode) | |
2822 | { | |
2823 | inode_free_security(inode); | |
2824 | } | |
2825 | ||
d47be3df | 2826 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
15bf3239 VG |
2827 | const struct qstr *name, |
2828 | const char **xattr_name, void **ctx, | |
d47be3df DQ |
2829 | u32 *ctxlen) |
2830 | { | |
d47be3df DQ |
2831 | u32 newsid; |
2832 | int rc; | |
2833 | ||
0c6cfa62 | 2834 | rc = selinux_determine_inode_label(selinux_cred(current_cred()), |
c957f6df | 2835 | d_inode(dentry->d_parent), name, |
c3c188b2 DH |
2836 | inode_mode_to_security_class(mode), |
2837 | &newsid); | |
2838 | if (rc) | |
2839 | return rc; | |
d47be3df | 2840 | |
15bf3239 VG |
2841 | if (xattr_name) |
2842 | *xattr_name = XATTR_NAME_SELINUX; | |
2843 | ||
aa8e712c SS |
2844 | return security_sid_to_context(&selinux_state, newsid, (char **)ctx, |
2845 | ctxlen); | |
d47be3df DQ |
2846 | } |
2847 | ||
a518b0a5 VG |
2848 | static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, |
2849 | struct qstr *name, | |
2850 | const struct cred *old, | |
2851 | struct cred *new) | |
2852 | { | |
2853 | u32 newsid; | |
2854 | int rc; | |
2855 | struct task_security_struct *tsec; | |
2856 | ||
0c6cfa62 | 2857 | rc = selinux_determine_inode_label(selinux_cred(old), |
a518b0a5 VG |
2858 | d_inode(dentry->d_parent), name, |
2859 | inode_mode_to_security_class(mode), | |
2860 | &newsid); | |
2861 | if (rc) | |
2862 | return rc; | |
2863 | ||
0c6cfa62 | 2864 | tsec = selinux_cred(new); |
a518b0a5 VG |
2865 | tsec->create_sid = newsid; |
2866 | return 0; | |
2867 | } | |
2868 | ||
5e41ff9e | 2869 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
2870 | const struct qstr *qstr, |
2871 | const char **name, | |
2a7dba39 | 2872 | void **value, size_t *len) |
5e41ff9e | 2873 | { |
0c6cfa62 | 2874 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
5e41ff9e | 2875 | struct superblock_security_struct *sbsec; |
c0d4f464 | 2876 | u32 newsid, clen; |
5e41ff9e | 2877 | int rc; |
9548906b | 2878 | char *context; |
5e41ff9e | 2879 | |
1aea7808 | 2880 | sbsec = selinux_superblock(dir->i_sb); |
5e41ff9e | 2881 | |
275bb41e DH |
2882 | newsid = tsec->create_sid; |
2883 | ||
210a2928 | 2884 | rc = selinux_determine_inode_label(tsec, dir, qstr, |
c3c188b2 DH |
2885 | inode_mode_to_security_class(inode->i_mode), |
2886 | &newsid); | |
2887 | if (rc) | |
2888 | return rc; | |
5e41ff9e | 2889 | |
296fddf7 | 2890 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 2891 | if (sbsec->flags & SE_SBINITIALIZED) { |
80788c22 | 2892 | struct inode_security_struct *isec = selinux_inode(inode); |
296fddf7 EP |
2893 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
2894 | isec->sid = newsid; | |
6f3be9f5 | 2895 | isec->initialized = LABEL_INITIALIZED; |
296fddf7 | 2896 | } |
5e41ff9e | 2897 | |
65cddd50 OM |
2898 | if (!selinux_initialized(&selinux_state) || |
2899 | !(sbsec->flags & SBLABEL_MNT)) | |
25a74f3b SS |
2900 | return -EOPNOTSUPP; |
2901 | ||
9548906b TH |
2902 | if (name) |
2903 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 2904 | |
570bc1c2 | 2905 | if (value && len) { |
aa8e712c SS |
2906 | rc = security_sid_to_context_force(&selinux_state, newsid, |
2907 | &context, &clen); | |
9548906b | 2908 | if (rc) |
570bc1c2 | 2909 | return rc; |
570bc1c2 SS |
2910 | *value = context; |
2911 | *len = clen; | |
5e41ff9e | 2912 | } |
5e41ff9e | 2913 | |
5e41ff9e SS |
2914 | return 0; |
2915 | } | |
2916 | ||
29cd6591 DC |
2917 | static int selinux_inode_init_security_anon(struct inode *inode, |
2918 | const struct qstr *name, | |
2919 | const struct inode *context_inode) | |
2920 | { | |
2921 | const struct task_security_struct *tsec = selinux_cred(current_cred()); | |
2922 | struct common_audit_data ad; | |
2923 | struct inode_security_struct *isec; | |
2924 | int rc; | |
2925 | ||
2926 | if (unlikely(!selinux_initialized(&selinux_state))) | |
2927 | return 0; | |
2928 | ||
2929 | isec = selinux_inode(inode); | |
2930 | ||
2931 | /* | |
2932 | * We only get here once per ephemeral inode. The inode has | |
2933 | * been initialized via inode_alloc_security but is otherwise | |
2934 | * untouched. | |
2935 | */ | |
2936 | ||
2937 | if (context_inode) { | |
2938 | struct inode_security_struct *context_isec = | |
2939 | selinux_inode(context_inode); | |
2940 | if (context_isec->initialized != LABEL_INITIALIZED) { | |
2941 | pr_err("SELinux: context_inode is not initialized"); | |
2942 | return -EACCES; | |
2943 | } | |
2944 | ||
2945 | isec->sclass = context_isec->sclass; | |
2946 | isec->sid = context_isec->sid; | |
2947 | } else { | |
2948 | isec->sclass = SECCLASS_ANON_INODE; | |
2949 | rc = security_transition_sid( | |
2950 | &selinux_state, tsec->sid, tsec->sid, | |
2951 | isec->sclass, name, &isec->sid); | |
2952 | if (rc) | |
2953 | return rc; | |
2954 | } | |
2955 | ||
2956 | isec->initialized = LABEL_INITIALIZED; | |
2957 | /* | |
2958 | * Now that we've initialized security, check whether we're | |
2959 | * allowed to actually create this type of anonymous inode. | |
2960 | */ | |
2961 | ||
c29722fa CG |
2962 | ad.type = LSM_AUDIT_DATA_ANONINODE; |
2963 | ad.u.anonclass = name ? (const char *)name->name : "?"; | |
29cd6591 DC |
2964 | |
2965 | return avc_has_perm(&selinux_state, | |
2966 | tsec->sid, | |
2967 | isec->sid, | |
2968 | isec->sclass, | |
2969 | FILE__CREATE, | |
2970 | &ad); | |
2971 | } | |
2972 | ||
4acdaf27 | 2973 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
2974 | { |
2975 | return may_create(dir, dentry, SECCLASS_FILE); | |
2976 | } | |
2977 | ||
1da177e4 LT |
2978 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2979 | { | |
1da177e4 LT |
2980 | return may_link(dir, old_dentry, MAY_LINK); |
2981 | } | |
2982 | ||
1da177e4 LT |
2983 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2984 | { | |
1da177e4 LT |
2985 | return may_link(dir, dentry, MAY_UNLINK); |
2986 | } | |
2987 | ||
2988 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2989 | { | |
2990 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2991 | } | |
2992 | ||
18bb1db3 | 2993 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
2994 | { |
2995 | return may_create(dir, dentry, SECCLASS_DIR); | |
2996 | } | |
2997 | ||
1da177e4 LT |
2998 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2999 | { | |
3000 | return may_link(dir, dentry, MAY_RMDIR); | |
3001 | } | |
3002 | ||
1a67aafb | 3003 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 3004 | { |
1da177e4 LT |
3005 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
3006 | } | |
3007 | ||
1da177e4 | 3008 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 3009 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
3010 | { |
3011 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
3012 | } | |
3013 | ||
1da177e4 LT |
3014 | static int selinux_inode_readlink(struct dentry *dentry) |
3015 | { | |
88e67f3b DH |
3016 | const struct cred *cred = current_cred(); |
3017 | ||
2875fa00 | 3018 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
3019 | } |
3020 | ||
bda0be7a N |
3021 | static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, |
3022 | bool rcu) | |
1da177e4 | 3023 | { |
88e67f3b | 3024 | const struct cred *cred = current_cred(); |
bda0be7a N |
3025 | struct common_audit_data ad; |
3026 | struct inode_security_struct *isec; | |
3027 | u32 sid; | |
1da177e4 | 3028 | |
bda0be7a N |
3029 | validate_creds(cred); |
3030 | ||
3031 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
3032 | ad.u.dentry = dentry; | |
3033 | sid = cred_sid(cred); | |
5d226df4 AG |
3034 | isec = inode_security_rcu(inode, rcu); |
3035 | if (IS_ERR(isec)) | |
3036 | return PTR_ERR(isec); | |
bda0be7a | 3037 | |
d99cf13f AV |
3038 | return avc_has_perm(&selinux_state, |
3039 | sid, isec->sid, isec->sclass, FILE__READ, &ad); | |
1da177e4 LT |
3040 | } |
3041 | ||
d4cf970d EP |
3042 | static noinline int audit_inode_permission(struct inode *inode, |
3043 | u32 perms, u32 audited, u32 denied, | |
0188d5c0 | 3044 | int result) |
1da177e4 | 3045 | { |
b782e0a6 | 3046 | struct common_audit_data ad; |
80788c22 | 3047 | struct inode_security_struct *isec = selinux_inode(inode); |
d4cf970d | 3048 | |
50c205f5 | 3049 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
3050 | ad.u.inode = inode; |
3051 | ||
b17ec22f | 3052 | return slow_avc_audit(&selinux_state, |
6b6bc620 | 3053 | current_sid(), isec->sid, isec->sclass, perms, |
0188d5c0 | 3054 | audited, denied, result, &ad); |
d4cf970d EP |
3055 | } |
3056 | ||
e74f71eb | 3057 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 3058 | { |
88e67f3b | 3059 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
3060 | u32 perms; |
3061 | bool from_access; | |
5298d0b9 | 3062 | bool no_block = mask & MAY_NOT_BLOCK; |
2e334057 EP |
3063 | struct inode_security_struct *isec; |
3064 | u32 sid; | |
3065 | struct av_decision avd; | |
3066 | int rc, rc2; | |
3067 | u32 audited, denied; | |
1da177e4 | 3068 | |
b782e0a6 | 3069 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
3070 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
3071 | ||
b782e0a6 EP |
3072 | /* No permission to check. Existence test. */ |
3073 | if (!mask) | |
1da177e4 | 3074 | return 0; |
1da177e4 | 3075 | |
2e334057 | 3076 | validate_creds(cred); |
b782e0a6 | 3077 | |
2e334057 EP |
3078 | if (unlikely(IS_PRIVATE(inode))) |
3079 | return 0; | |
b782e0a6 EP |
3080 | |
3081 | perms = file_mask_to_av(inode->i_mode, mask); | |
3082 | ||
2e334057 | 3083 | sid = cred_sid(cred); |
5298d0b9 | 3084 | isec = inode_security_rcu(inode, no_block); |
5d226df4 AG |
3085 | if (IS_ERR(isec)) |
3086 | return PTR_ERR(isec); | |
2e334057 | 3087 | |
6b6bc620 | 3088 | rc = avc_has_perm_noaudit(&selinux_state, |
b17ec22f | 3089 | sid, isec->sid, isec->sclass, perms, 0, |
3a28cff3 | 3090 | &avd); |
2e334057 EP |
3091 | audited = avc_audit_required(perms, &avd, rc, |
3092 | from_access ? FILE__AUDIT_ACCESS : 0, | |
3093 | &denied); | |
3094 | if (likely(!audited)) | |
3095 | return rc; | |
3096 | ||
0188d5c0 | 3097 | rc2 = audit_inode_permission(inode, perms, audited, denied, rc); |
2e334057 EP |
3098 | if (rc2) |
3099 | return rc2; | |
3100 | return rc; | |
1da177e4 LT |
3101 | } |
3102 | ||
3103 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
3104 | { | |
88e67f3b | 3105 | const struct cred *cred = current_cred(); |
ccb54478 | 3106 | struct inode *inode = d_backing_inode(dentry); |
bc6a6008 | 3107 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 3108 | __u32 av = FILE__WRITE; |
1da177e4 | 3109 | |
bc6a6008 AW |
3110 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
3111 | if (ia_valid & ATTR_FORCE) { | |
3112 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
3113 | ATTR_FORCE); | |
3114 | if (!ia_valid) | |
3115 | return 0; | |
3116 | } | |
1da177e4 | 3117 | |
bc6a6008 AW |
3118 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
3119 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 3120 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 3121 | |
aa8e712c | 3122 | if (selinux_policycap_openperm() && |
ccb54478 SS |
3123 | inode->i_sb->s_magic != SOCKFS_MAGIC && |
3124 | (ia_valid & ATTR_SIZE) && | |
3125 | !(ia_valid & ATTR_FILE)) | |
95dbf739 EP |
3126 | av |= FILE__OPEN; |
3127 | ||
3128 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
3129 | } |
3130 | ||
3f7036a0 | 3131 | static int selinux_inode_getattr(const struct path *path) |
1da177e4 | 3132 | { |
3f7036a0 | 3133 | return path_has_perm(current_cred(), path, FILE__GETATTR); |
1da177e4 LT |
3134 | } |
3135 | ||
db59000a SS |
3136 | static bool has_cap_mac_admin(bool audit) |
3137 | { | |
3138 | const struct cred *cred = current_cred(); | |
c1a85a00 | 3139 | unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT; |
db59000a | 3140 | |
c1a85a00 | 3141 | if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts)) |
db59000a | 3142 | return false; |
c1a85a00 | 3143 | if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true)) |
db59000a SS |
3144 | return false; |
3145 | return true; | |
3146 | } | |
3147 | ||
39f60c1c | 3148 | static int selinux_inode_setxattr(struct mnt_idmap *idmap, |
71bc356f | 3149 | struct dentry *dentry, const char *name, |
8f0cfa52 | 3150 | const void *value, size_t size, int flags) |
1da177e4 | 3151 | { |
c6f493d6 | 3152 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3153 | struct inode_security_struct *isec; |
1da177e4 | 3154 | struct superblock_security_struct *sbsec; |
2bf49690 | 3155 | struct common_audit_data ad; |
275bb41e | 3156 | u32 newsid, sid = current_sid(); |
39f60c1c | 3157 | struct user_namespace *mnt_userns = mnt_idmap_owner(idmap); |
1da177e4 LT |
3158 | int rc = 0; |
3159 | ||
6b240306 EB |
3160 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
3161 | rc = cap_inode_setxattr(dentry, name, value, size, flags); | |
3162 | if (rc) | |
3163 | return rc; | |
3164 | ||
3165 | /* Not an attribute we recognize, so just check the | |
3166 | ordinary setattr permission. */ | |
3167 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3168 | } | |
1da177e4 | 3169 | |
65cddd50 | 3170 | if (!selinux_initialized(&selinux_state)) |
71bc356f | 3171 | return (inode_owner_or_capable(mnt_userns, inode) ? 0 : -EPERM); |
3e3e24b4 | 3172 | |
1aea7808 | 3173 | sbsec = selinux_superblock(inode->i_sb); |
12f348b9 | 3174 | if (!(sbsec->flags & SBLABEL_MNT)) |
1da177e4 LT |
3175 | return -EOPNOTSUPP; |
3176 | ||
71bc356f | 3177 | if (!inode_owner_or_capable(mnt_userns, inode)) |
1da177e4 LT |
3178 | return -EPERM; |
3179 | ||
50c205f5 | 3180 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 3181 | ad.u.dentry = dentry; |
1da177e4 | 3182 | |
20cdef8d | 3183 | isec = backing_inode_security(dentry); |
6b6bc620 SS |
3184 | rc = avc_has_perm(&selinux_state, |
3185 | sid, isec->sid, isec->sclass, | |
1da177e4 LT |
3186 | FILE__RELABELFROM, &ad); |
3187 | if (rc) | |
3188 | return rc; | |
3189 | ||
aa8e712c SS |
3190 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3191 | GFP_KERNEL); | |
12b29f34 | 3192 | if (rc == -EINVAL) { |
db59000a | 3193 | if (!has_cap_mac_admin(true)) { |
d6ea83ec EP |
3194 | struct audit_buffer *ab; |
3195 | size_t audit_size; | |
d6ea83ec EP |
3196 | |
3197 | /* We strip a nul only if it is at the end, otherwise the | |
3198 | * context contains a nul and we should audit that */ | |
e3fea3f7 | 3199 | if (value) { |
add24372 CIK |
3200 | const char *str = value; |
3201 | ||
e3fea3f7 AV |
3202 | if (str[size - 1] == '\0') |
3203 | audit_size = size - 1; | |
3204 | else | |
3205 | audit_size = size; | |
3206 | } else { | |
e3fea3f7 AV |
3207 | audit_size = 0; |
3208 | } | |
cdfb6b34 RGB |
3209 | ab = audit_log_start(audit_context(), |
3210 | GFP_ATOMIC, AUDIT_SELINUX_ERR); | |
893c47d1 AK |
3211 | if (!ab) |
3212 | return rc; | |
d6ea83ec EP |
3213 | audit_log_format(ab, "op=setxattr invalid_context="); |
3214 | audit_log_n_untrustedstring(ab, value, audit_size); | |
3215 | audit_log_end(ab); | |
3216 | ||
12b29f34 | 3217 | return rc; |
d6ea83ec | 3218 | } |
aa8e712c SS |
3219 | rc = security_context_to_sid_force(&selinux_state, value, |
3220 | size, &newsid); | |
12b29f34 | 3221 | } |
1da177e4 LT |
3222 | if (rc) |
3223 | return rc; | |
3224 | ||
6b6bc620 SS |
3225 | rc = avc_has_perm(&selinux_state, |
3226 | sid, newsid, isec->sclass, | |
1da177e4 LT |
3227 | FILE__RELABELTO, &ad); |
3228 | if (rc) | |
3229 | return rc; | |
3230 | ||
aa8e712c SS |
3231 | rc = security_validate_transition(&selinux_state, isec->sid, newsid, |
3232 | sid, isec->sclass); | |
1da177e4 LT |
3233 | if (rc) |
3234 | return rc; | |
3235 | ||
6b6bc620 SS |
3236 | return avc_has_perm(&selinux_state, |
3237 | newsid, | |
1da177e4 LT |
3238 | sbsec->sid, |
3239 | SECCLASS_FILESYSTEM, | |
3240 | FILESYSTEM__ASSOCIATE, | |
3241 | &ad); | |
3242 | } | |
3243 | ||
700b7940 | 3244 | static int selinux_inode_set_acl(struct mnt_idmap *idmap, |
1bdeb218 CB |
3245 | struct dentry *dentry, const char *acl_name, |
3246 | struct posix_acl *kacl) | |
3247 | { | |
3248 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3249 | } | |
3250 | ||
700b7940 | 3251 | static int selinux_inode_get_acl(struct mnt_idmap *idmap, |
1bdeb218 CB |
3252 | struct dentry *dentry, const char *acl_name) |
3253 | { | |
3254 | return dentry_has_perm(current_cred(), dentry, FILE__GETATTR); | |
3255 | } | |
3256 | ||
700b7940 | 3257 | static int selinux_inode_remove_acl(struct mnt_idmap *idmap, |
1bdeb218 CB |
3258 | struct dentry *dentry, const char *acl_name) |
3259 | { | |
3260 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3261 | } | |
3262 | ||
8f0cfa52 | 3263 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 3264 | const void *value, size_t size, |
8f0cfa52 | 3265 | int flags) |
1da177e4 | 3266 | { |
c6f493d6 | 3267 | struct inode *inode = d_backing_inode(dentry); |
20cdef8d | 3268 | struct inode_security_struct *isec; |
1da177e4 LT |
3269 | u32 newsid; |
3270 | int rc; | |
3271 | ||
3272 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
3273 | /* Not an attribute we recognize, so nothing to do. */ | |
3274 | return; | |
3275 | } | |
3276 | ||
65cddd50 | 3277 | if (!selinux_initialized(&selinux_state)) { |
3e3e24b4 JL |
3278 | /* If we haven't even been initialized, then we can't validate |
3279 | * against a policy, so leave the label as invalid. It may | |
3280 | * resolve to a valid label on the next revalidation try if | |
3281 | * we've since initialized. | |
3282 | */ | |
3283 | return; | |
3284 | } | |
3285 | ||
aa8e712c SS |
3286 | rc = security_context_to_sid_force(&selinux_state, value, size, |
3287 | &newsid); | |
1da177e4 | 3288 | if (rc) { |
c103a91e | 3289 | pr_err("SELinux: unable to map context to SID" |
12b29f34 SS |
3290 | "for (%s, %lu), rc=%d\n", |
3291 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
3292 | return; |
3293 | } | |
3294 | ||
20cdef8d | 3295 | isec = backing_inode_security(dentry); |
9287aed2 | 3296 | spin_lock(&isec->lock); |
aa9c2669 | 3297 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3298 | isec->sid = newsid; |
6f3be9f5 | 3299 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3300 | spin_unlock(&isec->lock); |
1da177e4 LT |
3301 | } |
3302 | ||
8f0cfa52 | 3303 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 3304 | { |
88e67f3b DH |
3305 | const struct cred *cred = current_cred(); |
3306 | ||
2875fa00 | 3307 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3308 | } |
3309 | ||
828dfe1d | 3310 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 3311 | { |
88e67f3b DH |
3312 | const struct cred *cred = current_cred(); |
3313 | ||
2875fa00 | 3314 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3315 | } |
3316 | ||
39f60c1c | 3317 | static int selinux_inode_removexattr(struct mnt_idmap *idmap, |
71bc356f | 3318 | struct dentry *dentry, const char *name) |
1da177e4 | 3319 | { |
6b240306 | 3320 | if (strcmp(name, XATTR_NAME_SELINUX)) { |
39f60c1c | 3321 | int rc = cap_inode_removexattr(idmap, dentry, name); |
6b240306 EB |
3322 | if (rc) |
3323 | return rc; | |
3324 | ||
3325 | /* Not an attribute we recognize, so just check the | |
3326 | ordinary setattr permission. */ | |
3327 | return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); | |
3328 | } | |
1da177e4 | 3329 | |
9530a3e0 SS |
3330 | if (!selinux_initialized(&selinux_state)) |
3331 | return 0; | |
3332 | ||
1da177e4 LT |
3333 | /* No one is allowed to remove a SELinux security label. |
3334 | You can change the label, but all data must be labeled. */ | |
3335 | return -EACCES; | |
3336 | } | |
3337 | ||
ac5656d8 AG |
3338 | static int selinux_path_notify(const struct path *path, u64 mask, |
3339 | unsigned int obj_type) | |
3340 | { | |
3341 | int ret; | |
3342 | u32 perm; | |
3343 | ||
3344 | struct common_audit_data ad; | |
3345 | ||
3346 | ad.type = LSM_AUDIT_DATA_PATH; | |
3347 | ad.u.path = *path; | |
3348 | ||
3349 | /* | |
3350 | * Set permission needed based on the type of mark being set. | |
3351 | * Performs an additional check for sb watches. | |
3352 | */ | |
3353 | switch (obj_type) { | |
3354 | case FSNOTIFY_OBJ_TYPE_VFSMOUNT: | |
3355 | perm = FILE__WATCH_MOUNT; | |
3356 | break; | |
3357 | case FSNOTIFY_OBJ_TYPE_SB: | |
3358 | perm = FILE__WATCH_SB; | |
3359 | ret = superblock_has_perm(current_cred(), path->dentry->d_sb, | |
3360 | FILESYSTEM__WATCH, &ad); | |
3361 | if (ret) | |
3362 | return ret; | |
3363 | break; | |
3364 | case FSNOTIFY_OBJ_TYPE_INODE: | |
3365 | perm = FILE__WATCH; | |
3366 | break; | |
3367 | default: | |
3368 | return -EINVAL; | |
3369 | } | |
3370 | ||
3371 | /* blocking watches require the file:watch_with_perm permission */ | |
3372 | if (mask & (ALL_FSNOTIFY_PERM_EVENTS)) | |
3373 | perm |= FILE__WATCH_WITH_PERM; | |
3374 | ||
3375 | /* watches on read-like events need the file:watch_reads permission */ | |
3376 | if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE)) | |
3377 | perm |= FILE__WATCH_READS; | |
3378 | ||
3379 | return path_has_perm(current_cred(), path, perm); | |
3380 | } | |
3381 | ||
d381d8a9 | 3382 | /* |
abc69bb6 | 3383 | * Copy the inode security context value to the user. |
d381d8a9 JM |
3384 | * |
3385 | * Permission check is handled by selinux_inode_getxattr hook. | |
3386 | */ | |
4609e1f1 | 3387 | static int selinux_inode_getsecurity(struct mnt_idmap *idmap, |
71bc356f CB |
3388 | struct inode *inode, const char *name, |
3389 | void **buffer, bool alloc) | |
1da177e4 | 3390 | { |
42492594 DQ |
3391 | u32 size; |
3392 | int error; | |
3393 | char *context = NULL; | |
20cdef8d | 3394 | struct inode_security_struct *isec; |
d381d8a9 | 3395 | |
c8e22261 JL |
3396 | /* |
3397 | * If we're not initialized yet, then we can't validate contexts, so | |
3398 | * just let vfs_getxattr fall back to using the on-disk xattr. | |
3399 | */ | |
3400 | if (!selinux_initialized(&selinux_state) || | |
3401 | strcmp(name, XATTR_SELINUX_SUFFIX)) | |
8c8570fb | 3402 | return -EOPNOTSUPP; |
d381d8a9 | 3403 | |
abc69bb6 SS |
3404 | /* |
3405 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3406 | * value even if it is not defined by current policy; otherwise, | |
3407 | * use the in-core value under current policy. | |
3408 | * Use the non-auditing forms of the permission checks since | |
3409 | * getxattr may be called by unprivileged processes commonly | |
3410 | * and lack of permission just means that we fall back to the | |
3411 | * in-core context value, not a denial. | |
3412 | */ | |
20cdef8d | 3413 | isec = inode_security(inode); |
db59000a | 3414 | if (has_cap_mac_admin(false)) |
aa8e712c SS |
3415 | error = security_sid_to_context_force(&selinux_state, |
3416 | isec->sid, &context, | |
abc69bb6 SS |
3417 | &size); |
3418 | else | |
aa8e712c SS |
3419 | error = security_sid_to_context(&selinux_state, isec->sid, |
3420 | &context, &size); | |
42492594 DQ |
3421 | if (error) |
3422 | return error; | |
3423 | error = size; | |
3424 | if (alloc) { | |
3425 | *buffer = context; | |
3426 | goto out_nofree; | |
3427 | } | |
3428 | kfree(context); | |
3429 | out_nofree: | |
3430 | return error; | |
1da177e4 LT |
3431 | } |
3432 | ||
3433 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 3434 | const void *value, size_t size, int flags) |
1da177e4 | 3435 | { |
2c97165b | 3436 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
1aea7808 | 3437 | struct superblock_security_struct *sbsec; |
1da177e4 LT |
3438 | u32 newsid; |
3439 | int rc; | |
3440 | ||
3441 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3442 | return -EOPNOTSUPP; | |
3443 | ||
1aea7808 | 3444 | sbsec = selinux_superblock(inode->i_sb); |
53e0c2aa OM |
3445 | if (!(sbsec->flags & SBLABEL_MNT)) |
3446 | return -EOPNOTSUPP; | |
3447 | ||
1da177e4 LT |
3448 | if (!value || !size) |
3449 | return -EACCES; | |
3450 | ||
aa8e712c SS |
3451 | rc = security_context_to_sid(&selinux_state, value, size, &newsid, |
3452 | GFP_KERNEL); | |
1da177e4 LT |
3453 | if (rc) |
3454 | return rc; | |
3455 | ||
9287aed2 | 3456 | spin_lock(&isec->lock); |
aa9c2669 | 3457 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3458 | isec->sid = newsid; |
6f3be9f5 | 3459 | isec->initialized = LABEL_INITIALIZED; |
9287aed2 | 3460 | spin_unlock(&isec->lock); |
1da177e4 LT |
3461 | return 0; |
3462 | } | |
3463 | ||
3464 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3465 | { | |
3466 | const int len = sizeof(XATTR_NAME_SELINUX); | |
a9ffe682 AG |
3467 | |
3468 | if (!selinux_initialized(&selinux_state)) | |
3469 | return 0; | |
3470 | ||
1da177e4 LT |
3471 | if (buffer && len <= buffer_size) |
3472 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3473 | return len; | |
3474 | } | |
3475 | ||
d6335d77 | 3476 | static void selinux_inode_getsecid(struct inode *inode, u32 *secid) |
713a04ae | 3477 | { |
e817c2f3 | 3478 | struct inode_security_struct *isec = inode_security_novalidate(inode); |
713a04ae AD |
3479 | *secid = isec->sid; |
3480 | } | |
3481 | ||
56909eb3 VG |
3482 | static int selinux_inode_copy_up(struct dentry *src, struct cred **new) |
3483 | { | |
3484 | u32 sid; | |
3485 | struct task_security_struct *tsec; | |
3486 | struct cred *new_creds = *new; | |
3487 | ||
3488 | if (new_creds == NULL) { | |
3489 | new_creds = prepare_creds(); | |
3490 | if (!new_creds) | |
3491 | return -ENOMEM; | |
3492 | } | |
3493 | ||
0c6cfa62 | 3494 | tsec = selinux_cred(new_creds); |
56909eb3 VG |
3495 | /* Get label from overlay inode and set it in create_sid */ |
3496 | selinux_inode_getsecid(d_inode(src), &sid); | |
3497 | tsec->create_sid = sid; | |
3498 | *new = new_creds; | |
3499 | return 0; | |
3500 | } | |
3501 | ||
19472b69 VG |
3502 | static int selinux_inode_copy_up_xattr(const char *name) |
3503 | { | |
3504 | /* The copy_up hook above sets the initial context on an inode, but we | |
3505 | * don't then want to overwrite it by blindly copying all the lower | |
3506 | * xattrs up. Instead, we have to filter out SELinux-related xattrs. | |
3507 | */ | |
3508 | if (strcmp(name, XATTR_NAME_SELINUX) == 0) | |
3509 | return 1; /* Discard */ | |
3510 | /* | |
3511 | * Any other attribute apart from SELINUX is not claimed, supported | |
3512 | * by selinux. | |
3513 | */ | |
3514 | return -EOPNOTSUPP; | |
3515 | } | |
3516 | ||
ec882da5 OM |
3517 | /* kernfs node operations */ |
3518 | ||
c72c4cde Y |
3519 | static int selinux_kernfs_init_security(struct kernfs_node *kn_dir, |
3520 | struct kernfs_node *kn) | |
ec882da5 | 3521 | { |
169ce0c0 | 3522 | const struct task_security_struct *tsec = selinux_cred(current_cred()); |
ec882da5 OM |
3523 | u32 parent_sid, newsid, clen; |
3524 | int rc; | |
3525 | char *context; | |
3526 | ||
1537ad15 | 3527 | rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0); |
ec882da5 OM |
3528 | if (rc == -ENODATA) |
3529 | return 0; | |
3530 | else if (rc < 0) | |
3531 | return rc; | |
3532 | ||
3533 | clen = (u32)rc; | |
3534 | context = kmalloc(clen, GFP_KERNEL); | |
3535 | if (!context) | |
3536 | return -ENOMEM; | |
3537 | ||
1537ad15 | 3538 | rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen); |
ec882da5 OM |
3539 | if (rc < 0) { |
3540 | kfree(context); | |
3541 | return rc; | |
3542 | } | |
3543 | ||
3544 | rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid, | |
3545 | GFP_KERNEL); | |
3546 | kfree(context); | |
3547 | if (rc) | |
3548 | return rc; | |
3549 | ||
3550 | if (tsec->create_sid) { | |
3551 | newsid = tsec->create_sid; | |
3552 | } else { | |
3553 | u16 secclass = inode_mode_to_security_class(kn->mode); | |
3554 | struct qstr q; | |
3555 | ||
3556 | q.name = kn->name; | |
3557 | q.hash_len = hashlen_string(kn_dir, kn->name); | |
3558 | ||
3559 | rc = security_transition_sid(&selinux_state, tsec->sid, | |
3560 | parent_sid, secclass, &q, | |
3561 | &newsid); | |
3562 | if (rc) | |
3563 | return rc; | |
3564 | } | |
3565 | ||
3566 | rc = security_sid_to_context_force(&selinux_state, newsid, | |
3567 | &context, &clen); | |
3568 | if (rc) | |
3569 | return rc; | |
3570 | ||
1537ad15 OM |
3571 | rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen, |
3572 | XATTR_CREATE); | |
ec882da5 OM |
3573 | kfree(context); |
3574 | return rc; | |
3575 | } | |
3576 | ||
3577 | ||
1da177e4 LT |
3578 | /* file security operations */ |
3579 | ||
788e7dd4 | 3580 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3581 | { |
88e67f3b | 3582 | const struct cred *cred = current_cred(); |
496ad9aa | 3583 | struct inode *inode = file_inode(file); |
1da177e4 | 3584 | |
1da177e4 LT |
3585 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3586 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3587 | mask |= MAY_APPEND; | |
3588 | ||
389fb800 PM |
3589 | return file_has_perm(cred, file, |
3590 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3591 | } |
3592 | ||
788e7dd4 YN |
3593 | static int selinux_file_permission(struct file *file, int mask) |
3594 | { | |
496ad9aa | 3595 | struct inode *inode = file_inode(file); |
bb6c6b02 | 3596 | struct file_security_struct *fsec = selinux_file(file); |
b197367e | 3597 | struct inode_security_struct *isec; |
20dda18b SS |
3598 | u32 sid = current_sid(); |
3599 | ||
389fb800 | 3600 | if (!mask) |
788e7dd4 YN |
3601 | /* No permission to check. Existence test. */ |
3602 | return 0; | |
788e7dd4 | 3603 | |
b197367e | 3604 | isec = inode_security(inode); |
20dda18b | 3605 | if (sid == fsec->sid && fsec->isid == isec->sid && |
6b6bc620 | 3606 | fsec->pseqno == avc_policy_seqno(&selinux_state)) |
83d49856 | 3607 | /* No change since file_open check. */ |
20dda18b SS |
3608 | return 0; |
3609 | ||
788e7dd4 YN |
3610 | return selinux_revalidate_file_permission(file, mask); |
3611 | } | |
3612 | ||
1da177e4 LT |
3613 | static int selinux_file_alloc_security(struct file *file) |
3614 | { | |
cb89e246 PM |
3615 | struct file_security_struct *fsec = selinux_file(file); |
3616 | u32 sid = current_sid(); | |
3617 | ||
3618 | fsec->sid = sid; | |
3619 | fsec->fown_sid = sid; | |
3620 | ||
3621 | return 0; | |
1da177e4 LT |
3622 | } |
3623 | ||
fa1aa143 JVS |
3624 | /* |
3625 | * Check whether a task has the ioctl permission and cmd | |
3626 | * operation to an inode. | |
3627 | */ | |
1d2a168a | 3628 | static int ioctl_has_perm(const struct cred *cred, struct file *file, |
fa1aa143 JVS |
3629 | u32 requested, u16 cmd) |
3630 | { | |
3631 | struct common_audit_data ad; | |
bb6c6b02 | 3632 | struct file_security_struct *fsec = selinux_file(file); |
fa1aa143 | 3633 | struct inode *inode = file_inode(file); |
20cdef8d | 3634 | struct inode_security_struct *isec; |
fa1aa143 JVS |
3635 | struct lsm_ioctlop_audit ioctl; |
3636 | u32 ssid = cred_sid(cred); | |
3637 | int rc; | |
3638 | u8 driver = cmd >> 8; | |
3639 | u8 xperm = cmd & 0xff; | |
3640 | ||
3641 | ad.type = LSM_AUDIT_DATA_IOCTL_OP; | |
3642 | ad.u.op = &ioctl; | |
3643 | ad.u.op->cmd = cmd; | |
3644 | ad.u.op->path = file->f_path; | |
3645 | ||
3646 | if (ssid != fsec->sid) { | |
6b6bc620 SS |
3647 | rc = avc_has_perm(&selinux_state, |
3648 | ssid, fsec->sid, | |
fa1aa143 JVS |
3649 | SECCLASS_FD, |
3650 | FD__USE, | |
3651 | &ad); | |
3652 | if (rc) | |
3653 | goto out; | |
3654 | } | |
3655 | ||
3656 | if (unlikely(IS_PRIVATE(inode))) | |
3657 | return 0; | |
3658 | ||
20cdef8d | 3659 | isec = inode_security(inode); |
6b6bc620 SS |
3660 | rc = avc_has_extended_perms(&selinux_state, |
3661 | ssid, isec->sid, isec->sclass, | |
3662 | requested, driver, xperm, &ad); | |
fa1aa143 JVS |
3663 | out: |
3664 | return rc; | |
3665 | } | |
3666 | ||
1da177e4 LT |
3667 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, |
3668 | unsigned long arg) | |
3669 | { | |
88e67f3b | 3670 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3671 | int error = 0; |
1da177e4 | 3672 | |
0b24dcb7 EP |
3673 | switch (cmd) { |
3674 | case FIONREAD: | |
0b24dcb7 | 3675 | case FIBMAP: |
0b24dcb7 | 3676 | case FIGETBSZ: |
2f99c369 | 3677 | case FS_IOC_GETFLAGS: |
2f99c369 | 3678 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3679 | error = file_has_perm(cred, file, FILE__GETATTR); |
3680 | break; | |
1da177e4 | 3681 | |
2f99c369 | 3682 | case FS_IOC_SETFLAGS: |
2f99c369 | 3683 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3684 | error = file_has_perm(cred, file, FILE__SETATTR); |
3685 | break; | |
3686 | ||
3687 | /* sys_ioctl() checks */ | |
3688 | case FIONBIO: | |
0b24dcb7 EP |
3689 | case FIOASYNC: |
3690 | error = file_has_perm(cred, file, 0); | |
3691 | break; | |
1da177e4 | 3692 | |
0b24dcb7 EP |
3693 | case KDSKBENT: |
3694 | case KDSKBSENT: | |
6a9de491 | 3695 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
c1a85a00 | 3696 | CAP_OPT_NONE, true); |
0b24dcb7 EP |
3697 | break; |
3698 | ||
65881e1d RH |
3699 | case FIOCLEX: |
3700 | case FIONCLEX: | |
3701 | if (!selinux_policycap_ioctl_skip_cloexec()) | |
3702 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); | |
3703 | break; | |
3704 | ||
0b24dcb7 EP |
3705 | /* default case assumes that the command will go |
3706 | * to the file's ioctl() function. | |
3707 | */ | |
3708 | default: | |
fa1aa143 | 3709 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); |
0b24dcb7 EP |
3710 | } |
3711 | return error; | |
1da177e4 LT |
3712 | } |
3713 | ||
b78b7d59 | 3714 | static int default_noexec __ro_after_init; |
fcaaade1 | 3715 | |
1da177e4 LT |
3716 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3717 | { | |
88e67f3b | 3718 | const struct cred *cred = current_cred(); |
be0554c9 | 3719 | u32 sid = cred_sid(cred); |
d84f4f99 | 3720 | int rc = 0; |
88e67f3b | 3721 | |
fcaaade1 | 3722 | if (default_noexec && |
892e8cac SS |
3723 | (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || |
3724 | (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3725 | /* |
3726 | * We are making executable an anonymous mapping or a | |
3727 | * private file mapping that will also be writable. | |
3728 | * This has an additional check. | |
3729 | */ | |
6b6bc620 SS |
3730 | rc = avc_has_perm(&selinux_state, |
3731 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3732 | PROCESS__EXECMEM, NULL); |
1da177e4 | 3733 | if (rc) |
d84f4f99 | 3734 | goto error; |
1da177e4 | 3735 | } |
1da177e4 LT |
3736 | |
3737 | if (file) { | |
3738 | /* read access is always possible with a mapping */ | |
3739 | u32 av = FILE__READ; | |
3740 | ||
3741 | /* write access only matters if the mapping is shared */ | |
3742 | if (shared && (prot & PROT_WRITE)) | |
3743 | av |= FILE__WRITE; | |
3744 | ||
3745 | if (prot & PROT_EXEC) | |
3746 | av |= FILE__EXECUTE; | |
3747 | ||
88e67f3b | 3748 | return file_has_perm(cred, file, av); |
1da177e4 | 3749 | } |
d84f4f99 DH |
3750 | |
3751 | error: | |
3752 | return rc; | |
1da177e4 LT |
3753 | } |
3754 | ||
e5467859 | 3755 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3756 | { |
b1d9e6b0 | 3757 | int rc = 0; |
1da177e4 | 3758 | |
a2551df7 | 3759 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
98883bfd | 3760 | u32 sid = current_sid(); |
6b6bc620 SS |
3761 | rc = avc_has_perm(&selinux_state, |
3762 | sid, sid, SECCLASS_MEMPROTECT, | |
ed032189 | 3763 | MEMPROTECT__MMAP_ZERO, NULL); |
84336d1a EP |
3764 | } |
3765 | ||
98883bfd | 3766 | return rc; |
e5467859 | 3767 | } |
1da177e4 | 3768 | |
e5467859 AV |
3769 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3770 | unsigned long prot, unsigned long flags) | |
3771 | { | |
3ba4bf5f SS |
3772 | struct common_audit_data ad; |
3773 | int rc; | |
3774 | ||
3775 | if (file) { | |
3776 | ad.type = LSM_AUDIT_DATA_FILE; | |
3777 | ad.u.file = file; | |
3778 | rc = inode_has_perm(current_cred(), file_inode(file), | |
3779 | FILE__MAP, &ad); | |
3780 | if (rc) | |
3781 | return rc; | |
3782 | } | |
3783 | ||
8861d0af | 3784 | if (checkreqprot_get(&selinux_state)) |
1da177e4 LT |
3785 | prot = reqprot; |
3786 | ||
3787 | return file_map_prot_check(file, prot, | |
3788 | (flags & MAP_TYPE) == MAP_SHARED); | |
3789 | } | |
3790 | ||
3791 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3792 | unsigned long reqprot, | |
3793 | unsigned long prot) | |
3794 | { | |
88e67f3b | 3795 | const struct cred *cred = current_cred(); |
be0554c9 | 3796 | u32 sid = cred_sid(cred); |
1da177e4 | 3797 | |
8861d0af | 3798 | if (checkreqprot_get(&selinux_state)) |
1da177e4 LT |
3799 | prot = reqprot; |
3800 | ||
fcaaade1 SS |
3801 | if (default_noexec && |
3802 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3803 | int rc = 0; |
db4c9641 SS |
3804 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3805 | vma->vm_end <= vma->vm_mm->brk) { | |
6b6bc620 SS |
3806 | rc = avc_has_perm(&selinux_state, |
3807 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3808 | PROCESS__EXECHEAP, NULL); |
db4c9641 | 3809 | } else if (!vma->vm_file && |
c2316dbf SS |
3810 | ((vma->vm_start <= vma->vm_mm->start_stack && |
3811 | vma->vm_end >= vma->vm_mm->start_stack) || | |
d17af505 | 3812 | vma_is_stack_for_current(vma))) { |
6b6bc620 SS |
3813 | rc = avc_has_perm(&selinux_state, |
3814 | sid, sid, SECCLASS_PROCESS, | |
be0554c9 | 3815 | PROCESS__EXECSTACK, NULL); |
db4c9641 SS |
3816 | } else if (vma->vm_file && vma->anon_vma) { |
3817 | /* | |
3818 | * We are making executable a file mapping that has | |
3819 | * had some COW done. Since pages might have been | |
3820 | * written, check ability to execute the possibly | |
3821 | * modified content. This typically should only | |
3822 | * occur for text relocations. | |
3823 | */ | |
d84f4f99 | 3824 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3825 | } |