Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * NSA Security-Enhanced Linux (SELinux) security module | |
3 | * | |
4 | * This file contains the SELinux hook function implementations. | |
5 | * | |
6 | * Authors: Stephen Smalley, <sds@epoch.ncsc.mil> | |
828dfe1d EP |
7 | * Chris Vance, <cvance@nai.com> |
8 | * Wayne Salamon, <wsalamon@nai.com> | |
9 | * James Morris <jmorris@redhat.com> | |
1da177e4 LT |
10 | * |
11 | * Copyright (C) 2001,2002 Networks Associates Technology, Inc. | |
2069f457 EP |
12 | * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> |
13 | * Eric Paris <eparis@redhat.com> | |
1da177e4 | 14 | * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. |
828dfe1d | 15 | * <dgoeddel@trustedcs.com> |
ed6d76e4 | 16 | * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. |
82c21bfa | 17 | * Paul Moore <paul@paul-moore.com> |
788e7dd4 | 18 | * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. |
828dfe1d | 19 | * Yuichi Nakamura <ynakam@hitachisoft.jp> |
1da177e4 LT |
20 | * |
21 | * This program is free software; you can redistribute it and/or modify | |
22 | * it under the terms of the GNU General Public License version 2, | |
828dfe1d | 23 | * as published by the Free Software Foundation. |
1da177e4 LT |
24 | */ |
25 | ||
1da177e4 | 26 | #include <linux/init.h> |
0b24dcb7 | 27 | #include <linux/kd.h> |
1da177e4 | 28 | #include <linux/kernel.h> |
0d094efe | 29 | #include <linux/tracehook.h> |
1da177e4 LT |
30 | #include <linux/errno.h> |
31 | #include <linux/sched.h> | |
32 | #include <linux/security.h> | |
33 | #include <linux/xattr.h> | |
34 | #include <linux/capability.h> | |
35 | #include <linux/unistd.h> | |
36 | #include <linux/mm.h> | |
37 | #include <linux/mman.h> | |
38 | #include <linux/slab.h> | |
39 | #include <linux/pagemap.h> | |
0b24dcb7 | 40 | #include <linux/proc_fs.h> |
1da177e4 | 41 | #include <linux/swap.h> |
1da177e4 LT |
42 | #include <linux/spinlock.h> |
43 | #include <linux/syscalls.h> | |
2a7dba39 | 44 | #include <linux/dcache.h> |
1da177e4 | 45 | #include <linux/file.h> |
9f3acc31 | 46 | #include <linux/fdtable.h> |
1da177e4 LT |
47 | #include <linux/namei.h> |
48 | #include <linux/mount.h> | |
1da177e4 LT |
49 | #include <linux/netfilter_ipv4.h> |
50 | #include <linux/netfilter_ipv6.h> | |
51 | #include <linux/tty.h> | |
52 | #include <net/icmp.h> | |
227b60f5 | 53 | #include <net/ip.h> /* for local_port_range[] */ |
ca10b9e9 | 54 | #include <net/sock.h> |
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> |
1da177e4 LT |
69 | #include <linux/quota.h> |
70 | #include <linux/un.h> /* for Unix socket types */ | |
71 | #include <net/af_unix.h> /* for Unix socket types */ | |
72 | #include <linux/parser.h> | |
73 | #include <linux/nfs_mount.h> | |
74 | #include <net/ipv6.h> | |
75 | #include <linux/hugetlb.h> | |
76 | #include <linux/personality.h> | |
1da177e4 | 77 | #include <linux/audit.h> |
6931dfc9 | 78 | #include <linux/string.h> |
877ce7c1 | 79 | #include <linux/selinux.h> |
23970741 | 80 | #include <linux/mutex.h> |
f06febc9 | 81 | #include <linux/posix-timers.h> |
00234592 | 82 | #include <linux/syslog.h> |
3486740a | 83 | #include <linux/user_namespace.h> |
44fc7ea0 | 84 | #include <linux/export.h> |
40401530 AV |
85 | #include <linux/msg.h> |
86 | #include <linux/shm.h> | |
1da177e4 LT |
87 | |
88 | #include "avc.h" | |
89 | #include "objsec.h" | |
90 | #include "netif.h" | |
224dfbd8 | 91 | #include "netnode.h" |
3e112172 | 92 | #include "netport.h" |
d28d1e08 | 93 | #include "xfrm.h" |
c60475bf | 94 | #include "netlabel.h" |
9d57a7f9 | 95 | #include "audit.h" |
7b98a585 | 96 | #include "avc_ss.h" |
1da177e4 | 97 | |
20510f2f | 98 | extern struct security_operations *security_ops; |
1da177e4 | 99 | |
d621d35e | 100 | /* SECMARK reference count */ |
56a4ca99 | 101 | static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); |
d621d35e | 102 | |
1da177e4 | 103 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
828dfe1d | 104 | int selinux_enforcing; |
1da177e4 LT |
105 | |
106 | static int __init enforcing_setup(char *str) | |
107 | { | |
f5269710 | 108 | unsigned long enforcing; |
29707b20 | 109 | if (!kstrtoul(str, 0, &enforcing)) |
f5269710 | 110 | selinux_enforcing = enforcing ? 1 : 0; |
1da177e4 LT |
111 | return 1; |
112 | } | |
113 | __setup("enforcing=", enforcing_setup); | |
114 | #endif | |
115 | ||
116 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM | |
117 | int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; | |
118 | ||
119 | static int __init selinux_enabled_setup(char *str) | |
120 | { | |
f5269710 | 121 | unsigned long enabled; |
29707b20 | 122 | if (!kstrtoul(str, 0, &enabled)) |
f5269710 | 123 | selinux_enabled = enabled ? 1 : 0; |
1da177e4 LT |
124 | return 1; |
125 | } | |
126 | __setup("selinux=", selinux_enabled_setup); | |
30d55280 SS |
127 | #else |
128 | int selinux_enabled = 1; | |
1da177e4 LT |
129 | #endif |
130 | ||
e18b890b | 131 | static struct kmem_cache *sel_inode_cache; |
7cae7e26 | 132 | |
d621d35e PM |
133 | /** |
134 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
135 | * | |
136 | * Description: | |
137 | * This function checks the SECMARK reference counter to see if any SECMARK | |
138 | * targets are currently configured, if the reference counter is greater than | |
139 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
2be4d74f CP |
140 | * enabled, false (0) if SECMARK is disabled. If the always_check_network |
141 | * policy capability is enabled, SECMARK is always considered enabled. | |
d621d35e PM |
142 | * |
143 | */ | |
144 | static int selinux_secmark_enabled(void) | |
145 | { | |
2be4d74f CP |
146 | return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount)); |
147 | } | |
148 | ||
149 | /** | |
150 | * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled | |
151 | * | |
152 | * Description: | |
153 | * This function checks if NetLabel or labeled IPSEC is enabled. Returns true | |
154 | * (1) if any are enabled or false (0) if neither are enabled. If the | |
155 | * always_check_network policy capability is enabled, peer labeling | |
156 | * is always considered enabled. | |
157 | * | |
158 | */ | |
159 | static int selinux_peerlbl_enabled(void) | |
160 | { | |
161 | return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled()); | |
d621d35e PM |
162 | } |
163 | ||
d84f4f99 DH |
164 | /* |
165 | * initialise the security for the init task | |
166 | */ | |
167 | static void cred_init_security(void) | |
1da177e4 | 168 | { |
3b11a1de | 169 | struct cred *cred = (struct cred *) current->real_cred; |
1da177e4 LT |
170 | struct task_security_struct *tsec; |
171 | ||
89d155ef | 172 | tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); |
1da177e4 | 173 | if (!tsec) |
d84f4f99 | 174 | panic("SELinux: Failed to initialize initial task.\n"); |
1da177e4 | 175 | |
d84f4f99 | 176 | tsec->osid = tsec->sid = SECINITSID_KERNEL; |
f1752eec | 177 | cred->security = tsec; |
1da177e4 LT |
178 | } |
179 | ||
88e67f3b DH |
180 | /* |
181 | * get the security ID of a set of credentials | |
182 | */ | |
183 | static inline u32 cred_sid(const struct cred *cred) | |
184 | { | |
185 | const struct task_security_struct *tsec; | |
186 | ||
187 | tsec = cred->security; | |
188 | return tsec->sid; | |
189 | } | |
190 | ||
275bb41e | 191 | /* |
3b11a1de | 192 | * get the objective security ID of a task |
275bb41e DH |
193 | */ |
194 | static inline u32 task_sid(const struct task_struct *task) | |
195 | { | |
275bb41e DH |
196 | u32 sid; |
197 | ||
198 | rcu_read_lock(); | |
88e67f3b | 199 | sid = cred_sid(__task_cred(task)); |
275bb41e DH |
200 | rcu_read_unlock(); |
201 | return sid; | |
202 | } | |
203 | ||
204 | /* | |
3b11a1de | 205 | * get the subjective security ID of the current task |
275bb41e DH |
206 | */ |
207 | static inline u32 current_sid(void) | |
208 | { | |
5fb49870 | 209 | const struct task_security_struct *tsec = current_security(); |
275bb41e DH |
210 | |
211 | return tsec->sid; | |
212 | } | |
213 | ||
88e67f3b DH |
214 | /* Allocate and free functions for each kind of security blob. */ |
215 | ||
1da177e4 LT |
216 | static int inode_alloc_security(struct inode *inode) |
217 | { | |
1da177e4 | 218 | struct inode_security_struct *isec; |
275bb41e | 219 | u32 sid = current_sid(); |
1da177e4 | 220 | |
a02fe132 | 221 | isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); |
1da177e4 LT |
222 | if (!isec) |
223 | return -ENOMEM; | |
224 | ||
23970741 | 225 | mutex_init(&isec->lock); |
1da177e4 | 226 | INIT_LIST_HEAD(&isec->list); |
1da177e4 LT |
227 | isec->inode = inode; |
228 | isec->sid = SECINITSID_UNLABELED; | |
229 | isec->sclass = SECCLASS_FILE; | |
275bb41e | 230 | isec->task_sid = sid; |
1da177e4 LT |
231 | inode->i_security = isec; |
232 | ||
233 | return 0; | |
234 | } | |
235 | ||
3dc91d43 SR |
236 | static void inode_free_rcu(struct rcu_head *head) |
237 | { | |
238 | struct inode_security_struct *isec; | |
239 | ||
240 | isec = container_of(head, struct inode_security_struct, rcu); | |
241 | kmem_cache_free(sel_inode_cache, isec); | |
242 | } | |
243 | ||
1da177e4 LT |
244 | static void inode_free_security(struct inode *inode) |
245 | { | |
246 | struct inode_security_struct *isec = inode->i_security; | |
247 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
248 | ||
1da177e4 LT |
249 | spin_lock(&sbsec->isec_lock); |
250 | if (!list_empty(&isec->list)) | |
251 | list_del_init(&isec->list); | |
252 | spin_unlock(&sbsec->isec_lock); | |
253 | ||
3dc91d43 SR |
254 | /* |
255 | * The inode may still be referenced in a path walk and | |
256 | * a call to selinux_inode_permission() can be made | |
257 | * after inode_free_security() is called. Ideally, the VFS | |
258 | * wouldn't do this, but fixing that is a much harder | |
259 | * job. For now, simply free the i_security via RCU, and | |
260 | * leave the current inode->i_security pointer intact. | |
261 | * The inode will be freed after the RCU grace period too. | |
262 | */ | |
263 | call_rcu(&isec->rcu, inode_free_rcu); | |
1da177e4 LT |
264 | } |
265 | ||
266 | static int file_alloc_security(struct file *file) | |
267 | { | |
1da177e4 | 268 | struct file_security_struct *fsec; |
275bb41e | 269 | u32 sid = current_sid(); |
1da177e4 | 270 | |
26d2a4be | 271 | fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); |
1da177e4 LT |
272 | if (!fsec) |
273 | return -ENOMEM; | |
274 | ||
275bb41e DH |
275 | fsec->sid = sid; |
276 | fsec->fown_sid = sid; | |
1da177e4 LT |
277 | file->f_security = fsec; |
278 | ||
279 | return 0; | |
280 | } | |
281 | ||
282 | static void file_free_security(struct file *file) | |
283 | { | |
284 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 LT |
285 | file->f_security = NULL; |
286 | kfree(fsec); | |
287 | } | |
288 | ||
289 | static int superblock_alloc_security(struct super_block *sb) | |
290 | { | |
291 | struct superblock_security_struct *sbsec; | |
292 | ||
89d155ef | 293 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
294 | if (!sbsec) |
295 | return -ENOMEM; | |
296 | ||
bc7e982b | 297 | mutex_init(&sbsec->lock); |
1da177e4 LT |
298 | INIT_LIST_HEAD(&sbsec->isec_head); |
299 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
300 | sbsec->sb = sb; |
301 | sbsec->sid = SECINITSID_UNLABELED; | |
302 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 303 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
304 | sb->s_security = sbsec; |
305 | ||
306 | return 0; | |
307 | } | |
308 | ||
309 | static void superblock_free_security(struct super_block *sb) | |
310 | { | |
311 | struct superblock_security_struct *sbsec = sb->s_security; | |
1da177e4 LT |
312 | sb->s_security = NULL; |
313 | kfree(sbsec); | |
314 | } | |
315 | ||
1da177e4 LT |
316 | /* The file system's label must be initialized prior to use. */ |
317 | ||
eb9ae686 | 318 | static const char *labeling_behaviors[7] = { |
1da177e4 LT |
319 | "uses xattr", |
320 | "uses transition SIDs", | |
321 | "uses task SIDs", | |
322 | "uses genfs_contexts", | |
323 | "not configured for labeling", | |
324 | "uses mountpoint labeling", | |
eb9ae686 | 325 | "uses native labeling", |
1da177e4 LT |
326 | }; |
327 | ||
328 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); | |
329 | ||
330 | static inline int inode_doinit(struct inode *inode) | |
331 | { | |
332 | return inode_doinit_with_dentry(inode, NULL); | |
333 | } | |
334 | ||
335 | enum { | |
31e87930 | 336 | Opt_error = -1, |
1da177e4 LT |
337 | Opt_context = 1, |
338 | Opt_fscontext = 2, | |
c9180a57 EP |
339 | Opt_defcontext = 3, |
340 | Opt_rootcontext = 4, | |
11689d47 | 341 | Opt_labelsupport = 5, |
d355987f | 342 | Opt_nextmntopt = 6, |
1da177e4 LT |
343 | }; |
344 | ||
d355987f EP |
345 | #define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) |
346 | ||
a447c093 | 347 | static const match_table_t tokens = { |
832cbd9a EP |
348 | {Opt_context, CONTEXT_STR "%s"}, |
349 | {Opt_fscontext, FSCONTEXT_STR "%s"}, | |
350 | {Opt_defcontext, DEFCONTEXT_STR "%s"}, | |
351 | {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, | |
11689d47 | 352 | {Opt_labelsupport, LABELSUPP_STR}, |
31e87930 | 353 | {Opt_error, NULL}, |
1da177e4 LT |
354 | }; |
355 | ||
356 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
357 | ||
c312feb2 EP |
358 | static int may_context_mount_sb_relabel(u32 sid, |
359 | struct superblock_security_struct *sbsec, | |
275bb41e | 360 | const struct cred *cred) |
c312feb2 | 361 | { |
275bb41e | 362 | const struct task_security_struct *tsec = cred->security; |
c312feb2 EP |
363 | int rc; |
364 | ||
365 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
366 | FILESYSTEM__RELABELFROM, NULL); | |
367 | if (rc) | |
368 | return rc; | |
369 | ||
370 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, | |
371 | FILESYSTEM__RELABELTO, NULL); | |
372 | return rc; | |
373 | } | |
374 | ||
0808925e EP |
375 | static int may_context_mount_inode_relabel(u32 sid, |
376 | struct superblock_security_struct *sbsec, | |
275bb41e | 377 | const struct cred *cred) |
0808925e | 378 | { |
275bb41e | 379 | const struct task_security_struct *tsec = cred->security; |
0808925e EP |
380 | int rc; |
381 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
382 | FILESYSTEM__RELABELFROM, NULL); | |
383 | if (rc) | |
384 | return rc; | |
385 | ||
386 | rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
387 | FILESYSTEM__ASSOCIATE, NULL); | |
388 | return rc; | |
389 | } | |
390 | ||
b43e725d EP |
391 | static int selinux_is_sblabel_mnt(struct super_block *sb) |
392 | { | |
393 | struct superblock_security_struct *sbsec = sb->s_security; | |
394 | ||
395 | if (sbsec->behavior == SECURITY_FS_USE_XATTR || | |
396 | sbsec->behavior == SECURITY_FS_USE_TRANS || | |
397 | sbsec->behavior == SECURITY_FS_USE_TASK) | |
398 | return 1; | |
399 | ||
400 | /* Special handling for sysfs. Is genfs but also has setxattr handler*/ | |
401 | if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0) | |
402 | return 1; | |
403 | ||
404 | /* | |
405 | * Special handling for rootfs. Is genfs but supports | |
406 | * setting SELinux context on in-core inodes. | |
407 | */ | |
408 | if (strncmp(sb->s_type->name, "rootfs", sizeof("rootfs")) == 0) | |
409 | return 1; | |
410 | ||
411 | return 0; | |
412 | } | |
413 | ||
c9180a57 | 414 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 415 | { |
1da177e4 | 416 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 EP |
417 | struct dentry *root = sb->s_root; |
418 | struct inode *root_inode = root->d_inode; | |
419 | int rc = 0; | |
1da177e4 | 420 | |
c9180a57 EP |
421 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
422 | /* Make sure that the xattr handler exists and that no | |
423 | error other than -ENODATA is returned by getxattr on | |
424 | the root directory. -ENODATA is ok, as this may be | |
425 | the first boot of the SELinux kernel before we have | |
426 | assigned xattr values to the filesystem. */ | |
427 | if (!root_inode->i_op->getxattr) { | |
29b1deb2 LT |
428 | printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " |
429 | "xattr support\n", sb->s_id, sb->s_type->name); | |
c9180a57 EP |
430 | rc = -EOPNOTSUPP; |
431 | goto out; | |
432 | } | |
433 | rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); | |
434 | if (rc < 0 && rc != -ENODATA) { | |
435 | if (rc == -EOPNOTSUPP) | |
436 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
29b1deb2 LT |
437 | "%s) has no security xattr handler\n", |
438 | sb->s_id, sb->s_type->name); | |
c9180a57 EP |
439 | else |
440 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
29b1deb2 LT |
441 | "%s) getxattr errno %d\n", sb->s_id, |
442 | sb->s_type->name, -rc); | |
c9180a57 EP |
443 | goto out; |
444 | } | |
445 | } | |
1da177e4 | 446 | |
c9180a57 | 447 | if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) |
29b1deb2 LT |
448 | printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", |
449 | sb->s_id, sb->s_type->name); | |
c9180a57 | 450 | else |
29b1deb2 LT |
451 | printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", |
452 | sb->s_id, sb->s_type->name, | |
c9180a57 | 453 | labeling_behaviors[sbsec->behavior-1]); |
1da177e4 | 454 | |
eadcabc6 | 455 | sbsec->flags |= SE_SBINITIALIZED; |
b43e725d | 456 | if (selinux_is_sblabel_mnt(sb)) |
12f348b9 | 457 | sbsec->flags |= SBLABEL_MNT; |
ddd29ec6 | 458 | |
c9180a57 EP |
459 | /* Initialize the root inode. */ |
460 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 461 | |
c9180a57 EP |
462 | /* Initialize any other inodes associated with the superblock, e.g. |
463 | inodes created prior to initial policy load or inodes created | |
464 | during get_sb by a pseudo filesystem that directly | |
465 | populates itself. */ | |
466 | spin_lock(&sbsec->isec_lock); | |
467 | next_inode: | |
468 | if (!list_empty(&sbsec->isec_head)) { | |
469 | struct inode_security_struct *isec = | |
470 | list_entry(sbsec->isec_head.next, | |
471 | struct inode_security_struct, list); | |
472 | struct inode *inode = isec->inode; | |
473 | spin_unlock(&sbsec->isec_lock); | |
474 | inode = igrab(inode); | |
475 | if (inode) { | |
476 | if (!IS_PRIVATE(inode)) | |
477 | inode_doinit(inode); | |
478 | iput(inode); | |
479 | } | |
480 | spin_lock(&sbsec->isec_lock); | |
481 | list_del_init(&isec->list); | |
482 | goto next_inode; | |
483 | } | |
484 | spin_unlock(&sbsec->isec_lock); | |
485 | out: | |
486 | return rc; | |
487 | } | |
1da177e4 | 488 | |
c9180a57 EP |
489 | /* |
490 | * This function should allow an FS to ask what it's mount security | |
491 | * options were so it can use those later for submounts, displaying | |
492 | * mount options, or whatever. | |
493 | */ | |
494 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
e0007529 | 495 | struct security_mnt_opts *opts) |
c9180a57 EP |
496 | { |
497 | int rc = 0, i; | |
498 | struct superblock_security_struct *sbsec = sb->s_security; | |
499 | char *context = NULL; | |
500 | u32 len; | |
501 | char tmp; | |
1da177e4 | 502 | |
e0007529 | 503 | security_init_mnt_opts(opts); |
1da177e4 | 504 | |
0d90a7ec | 505 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
c9180a57 | 506 | return -EINVAL; |
1da177e4 | 507 | |
c9180a57 EP |
508 | if (!ss_initialized) |
509 | return -EINVAL; | |
1da177e4 | 510 | |
af8e50cc EP |
511 | /* make sure we always check enough bits to cover the mask */ |
512 | BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); | |
513 | ||
0d90a7ec | 514 | tmp = sbsec->flags & SE_MNTMASK; |
c9180a57 | 515 | /* count the number of mount options for this sb */ |
af8e50cc | 516 | for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { |
c9180a57 | 517 | if (tmp & 0x01) |
e0007529 | 518 | opts->num_mnt_opts++; |
c9180a57 EP |
519 | tmp >>= 1; |
520 | } | |
11689d47 | 521 | /* Check if the Label support flag is set */ |
0b4bdb35 | 522 | if (sbsec->flags & SBLABEL_MNT) |
11689d47 | 523 | opts->num_mnt_opts++; |
1da177e4 | 524 | |
e0007529 EP |
525 | opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); |
526 | if (!opts->mnt_opts) { | |
c9180a57 EP |
527 | rc = -ENOMEM; |
528 | goto out_free; | |
529 | } | |
1da177e4 | 530 | |
e0007529 EP |
531 | opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); |
532 | if (!opts->mnt_opts_flags) { | |
c9180a57 EP |
533 | rc = -ENOMEM; |
534 | goto out_free; | |
535 | } | |
1da177e4 | 536 | |
c9180a57 EP |
537 | i = 0; |
538 | if (sbsec->flags & FSCONTEXT_MNT) { | |
539 | rc = security_sid_to_context(sbsec->sid, &context, &len); | |
540 | if (rc) | |
541 | goto out_free; | |
e0007529 EP |
542 | opts->mnt_opts[i] = context; |
543 | opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; | |
c9180a57 EP |
544 | } |
545 | if (sbsec->flags & CONTEXT_MNT) { | |
546 | rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); | |
547 | if (rc) | |
548 | goto out_free; | |
e0007529 EP |
549 | opts->mnt_opts[i] = context; |
550 | opts->mnt_opts_flags[i++] = CONTEXT_MNT; | |
c9180a57 EP |
551 | } |
552 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
553 | rc = security_sid_to_context(sbsec->def_sid, &context, &len); | |
554 | if (rc) | |
555 | goto out_free; | |
e0007529 EP |
556 | opts->mnt_opts[i] = context; |
557 | opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
558 | } |
559 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
560 | struct inode *root = sbsec->sb->s_root->d_inode; | |
561 | struct inode_security_struct *isec = root->i_security; | |
0808925e | 562 | |
c9180a57 EP |
563 | rc = security_sid_to_context(isec->sid, &context, &len); |
564 | if (rc) | |
565 | goto out_free; | |
e0007529 EP |
566 | opts->mnt_opts[i] = context; |
567 | opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; | |
c9180a57 | 568 | } |
12f348b9 | 569 | if (sbsec->flags & SBLABEL_MNT) { |
11689d47 | 570 | opts->mnt_opts[i] = NULL; |
12f348b9 | 571 | opts->mnt_opts_flags[i++] = SBLABEL_MNT; |
11689d47 | 572 | } |
1da177e4 | 573 | |
e0007529 | 574 | BUG_ON(i != opts->num_mnt_opts); |
1da177e4 | 575 | |
c9180a57 EP |
576 | return 0; |
577 | ||
578 | out_free: | |
e0007529 | 579 | security_free_mnt_opts(opts); |
c9180a57 EP |
580 | return rc; |
581 | } | |
1da177e4 | 582 | |
c9180a57 EP |
583 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
584 | u32 old_sid, u32 new_sid) | |
585 | { | |
0d90a7ec DQ |
586 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
587 | ||
c9180a57 | 588 | /* check if the old mount command had the same options */ |
0d90a7ec | 589 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
590 | if (!(sbsec->flags & flag) || |
591 | (old_sid != new_sid)) | |
592 | return 1; | |
593 | ||
594 | /* check if we were passed the same options twice, | |
595 | * aka someone passed context=a,context=b | |
596 | */ | |
0d90a7ec DQ |
597 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
598 | if (mnt_flags & flag) | |
c9180a57 EP |
599 | return 1; |
600 | return 0; | |
601 | } | |
e0007529 | 602 | |
c9180a57 EP |
603 | /* |
604 | * Allow filesystems with binary mount data to explicitly set mount point | |
605 | * labeling information. | |
606 | */ | |
e0007529 | 607 | static int selinux_set_mnt_opts(struct super_block *sb, |
649f6e77 DQ |
608 | struct security_mnt_opts *opts, |
609 | unsigned long kern_flags, | |
610 | unsigned long *set_kern_flags) | |
c9180a57 | 611 | { |
275bb41e | 612 | const struct cred *cred = current_cred(); |
c9180a57 | 613 | int rc = 0, i; |
c9180a57 | 614 | struct superblock_security_struct *sbsec = sb->s_security; |
29b1deb2 | 615 | const char *name = sb->s_type->name; |
089be43e JM |
616 | struct inode *inode = sbsec->sb->s_root->d_inode; |
617 | struct inode_security_struct *root_isec = inode->i_security; | |
c9180a57 EP |
618 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
619 | u32 defcontext_sid = 0; | |
e0007529 EP |
620 | char **mount_options = opts->mnt_opts; |
621 | int *flags = opts->mnt_opts_flags; | |
622 | int num_opts = opts->num_mnt_opts; | |
c9180a57 EP |
623 | |
624 | mutex_lock(&sbsec->lock); | |
625 | ||
626 | if (!ss_initialized) { | |
627 | if (!num_opts) { | |
628 | /* Defer initialization until selinux_complete_init, | |
629 | after the initial policy is loaded and the security | |
630 | server is ready to handle calls. */ | |
c9180a57 EP |
631 | goto out; |
632 | } | |
633 | rc = -EINVAL; | |
744ba35e EP |
634 | printk(KERN_WARNING "SELinux: Unable to set superblock options " |
635 | "before the security server is initialized\n"); | |
1da177e4 | 636 | goto out; |
c9180a57 | 637 | } |
649f6e77 DQ |
638 | if (kern_flags && !set_kern_flags) { |
639 | /* Specifying internal flags without providing a place to | |
640 | * place the results is not allowed */ | |
641 | rc = -EINVAL; | |
642 | goto out; | |
643 | } | |
1da177e4 | 644 | |
e0007529 EP |
645 | /* |
646 | * Binary mount data FS will come through this function twice. Once | |
647 | * from an explicit call and once from the generic calls from the vfs. | |
648 | * Since the generic VFS calls will not contain any security mount data | |
649 | * we need to skip the double mount verification. | |
650 | * | |
651 | * This does open a hole in which we will not notice if the first | |
652 | * mount using this sb set explict options and a second mount using | |
653 | * this sb does not set any security options. (The first options | |
654 | * will be used for both mounts) | |
655 | */ | |
0d90a7ec | 656 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
e0007529 | 657 | && (num_opts == 0)) |
f5269710 | 658 | goto out; |
e0007529 | 659 | |
c9180a57 EP |
660 | /* |
661 | * parse the mount options, check if they are valid sids. | |
662 | * also check if someone is trying to mount the same sb more | |
663 | * than once with different security options. | |
664 | */ | |
665 | for (i = 0; i < num_opts; i++) { | |
666 | u32 sid; | |
11689d47 | 667 | |
12f348b9 | 668 | if (flags[i] == SBLABEL_MNT) |
11689d47 | 669 | continue; |
c9180a57 | 670 | rc = security_context_to_sid(mount_options[i], |
52a4c640 | 671 | strlen(mount_options[i]), &sid, GFP_KERNEL); |
1da177e4 LT |
672 | if (rc) { |
673 | printk(KERN_WARNING "SELinux: security_context_to_sid" | |
29b1deb2 LT |
674 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
675 | mount_options[i], sb->s_id, name, rc); | |
c9180a57 EP |
676 | goto out; |
677 | } | |
678 | switch (flags[i]) { | |
679 | case FSCONTEXT_MNT: | |
680 | fscontext_sid = sid; | |
681 | ||
682 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
683 | fscontext_sid)) | |
684 | goto out_double_mount; | |
685 | ||
686 | sbsec->flags |= FSCONTEXT_MNT; | |
687 | break; | |
688 | case CONTEXT_MNT: | |
689 | context_sid = sid; | |
690 | ||
691 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
692 | context_sid)) | |
693 | goto out_double_mount; | |
694 | ||
695 | sbsec->flags |= CONTEXT_MNT; | |
696 | break; | |
697 | case ROOTCONTEXT_MNT: | |
698 | rootcontext_sid = sid; | |
699 | ||
700 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
701 | rootcontext_sid)) | |
702 | goto out_double_mount; | |
703 | ||
704 | sbsec->flags |= ROOTCONTEXT_MNT; | |
705 | ||
706 | break; | |
707 | case DEFCONTEXT_MNT: | |
708 | defcontext_sid = sid; | |
709 | ||
710 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
711 | defcontext_sid)) | |
712 | goto out_double_mount; | |
713 | ||
714 | sbsec->flags |= DEFCONTEXT_MNT; | |
715 | ||
716 | break; | |
717 | default: | |
718 | rc = -EINVAL; | |
719 | goto out; | |
1da177e4 | 720 | } |
c9180a57 EP |
721 | } |
722 | ||
0d90a7ec | 723 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 724 | /* previously mounted with options, but not on this attempt? */ |
0d90a7ec | 725 | if ((sbsec->flags & SE_MNTMASK) && !num_opts) |
c9180a57 EP |
726 | goto out_double_mount; |
727 | rc = 0; | |
728 | goto out; | |
729 | } | |
730 | ||
089be43e | 731 | if (strcmp(sb->s_type->name, "proc") == 0) |
0d90a7ec | 732 | sbsec->flags |= SE_SBPROC; |
c9180a57 | 733 | |
eb9ae686 DQ |
734 | if (!sbsec->behavior) { |
735 | /* | |
736 | * Determine the labeling behavior to use for this | |
737 | * filesystem type. | |
738 | */ | |
98f700f3 | 739 | rc = security_fs_use(sb); |
eb9ae686 DQ |
740 | if (rc) { |
741 | printk(KERN_WARNING | |
742 | "%s: security_fs_use(%s) returned %d\n", | |
743 | __func__, sb->s_type->name, rc); | |
744 | goto out; | |
745 | } | |
c9180a57 | 746 | } |
c9180a57 EP |
747 | /* sets the context of the superblock for the fs being mounted. */ |
748 | if (fscontext_sid) { | |
275bb41e | 749 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
1da177e4 | 750 | if (rc) |
c9180a57 | 751 | goto out; |
1da177e4 | 752 | |
c9180a57 | 753 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
754 | } |
755 | ||
756 | /* | |
757 | * Switch to using mount point labeling behavior. | |
758 | * sets the label used on all file below the mountpoint, and will set | |
759 | * the superblock context if not already set. | |
760 | */ | |
eb9ae686 DQ |
761 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { |
762 | sbsec->behavior = SECURITY_FS_USE_NATIVE; | |
763 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
764 | } | |
765 | ||
c9180a57 EP |
766 | if (context_sid) { |
767 | if (!fscontext_sid) { | |
275bb41e DH |
768 | rc = may_context_mount_sb_relabel(context_sid, sbsec, |
769 | cred); | |
b04ea3ce | 770 | if (rc) |
c9180a57 EP |
771 | goto out; |
772 | sbsec->sid = context_sid; | |
b04ea3ce | 773 | } else { |
275bb41e DH |
774 | rc = may_context_mount_inode_relabel(context_sid, sbsec, |
775 | cred); | |
b04ea3ce | 776 | if (rc) |
c9180a57 | 777 | goto out; |
b04ea3ce | 778 | } |
c9180a57 EP |
779 | if (!rootcontext_sid) |
780 | rootcontext_sid = context_sid; | |
1da177e4 | 781 | |
c9180a57 | 782 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 783 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
784 | } |
785 | ||
c9180a57 | 786 | if (rootcontext_sid) { |
275bb41e DH |
787 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
788 | cred); | |
0808925e | 789 | if (rc) |
c9180a57 | 790 | goto out; |
0808925e | 791 | |
c9180a57 EP |
792 | root_isec->sid = rootcontext_sid; |
793 | root_isec->initialized = 1; | |
0808925e EP |
794 | } |
795 | ||
c9180a57 | 796 | if (defcontext_sid) { |
eb9ae686 DQ |
797 | if (sbsec->behavior != SECURITY_FS_USE_XATTR && |
798 | sbsec->behavior != SECURITY_FS_USE_NATIVE) { | |
c9180a57 EP |
799 | rc = -EINVAL; |
800 | printk(KERN_WARNING "SELinux: defcontext option is " | |
801 | "invalid for this filesystem type\n"); | |
802 | goto out; | |
1da177e4 LT |
803 | } |
804 | ||
c9180a57 EP |
805 | if (defcontext_sid != sbsec->def_sid) { |
806 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
275bb41e | 807 | sbsec, cred); |
c9180a57 EP |
808 | if (rc) |
809 | goto out; | |
810 | } | |
1da177e4 | 811 | |
c9180a57 | 812 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
813 | } |
814 | ||
c9180a57 | 815 | rc = sb_finish_set_opts(sb); |
1da177e4 | 816 | out: |
c9180a57 | 817 | mutex_unlock(&sbsec->lock); |
1da177e4 | 818 | return rc; |
c9180a57 EP |
819 | out_double_mount: |
820 | rc = -EINVAL; | |
821 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " | |
29b1deb2 | 822 | "security settings for (dev %s, type %s)\n", sb->s_id, name); |
c9180a57 | 823 | goto out; |
1da177e4 LT |
824 | } |
825 | ||
094f7b69 JL |
826 | static int selinux_cmp_sb_context(const struct super_block *oldsb, |
827 | const struct super_block *newsb) | |
828 | { | |
829 | struct superblock_security_struct *old = oldsb->s_security; | |
830 | struct superblock_security_struct *new = newsb->s_security; | |
831 | char oldflags = old->flags & SE_MNTMASK; | |
832 | char newflags = new->flags & SE_MNTMASK; | |
833 | ||
834 | if (oldflags != newflags) | |
835 | goto mismatch; | |
836 | if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) | |
837 | goto mismatch; | |
838 | if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) | |
839 | goto mismatch; | |
840 | if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) | |
841 | goto mismatch; | |
842 | if (oldflags & ROOTCONTEXT_MNT) { | |
843 | struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security; | |
844 | struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security; | |
845 | if (oldroot->sid != newroot->sid) | |
846 | goto mismatch; | |
847 | } | |
848 | return 0; | |
849 | mismatch: | |
850 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " | |
851 | "different security settings for (dev %s, " | |
852 | "type %s)\n", newsb->s_id, newsb->s_type->name); | |
853 | return -EBUSY; | |
854 | } | |
855 | ||
856 | static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, | |
c9180a57 | 857 | struct super_block *newsb) |
1da177e4 | 858 | { |
c9180a57 EP |
859 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
860 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 861 | |
c9180a57 EP |
862 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
863 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
864 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 865 | |
0f5e6420 EP |
866 | /* |
867 | * if the parent was able to be mounted it clearly had no special lsm | |
e8c26255 | 868 | * mount options. thus we can safely deal with this superblock later |
0f5e6420 | 869 | */ |
e8c26255 | 870 | if (!ss_initialized) |
094f7b69 | 871 | return 0; |
c9180a57 | 872 | |
c9180a57 | 873 | /* how can we clone if the old one wasn't set up?? */ |
0d90a7ec | 874 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
c9180a57 | 875 | |
094f7b69 | 876 | /* if fs is reusing a sb, make sure that the contexts match */ |
0d90a7ec | 877 | if (newsbsec->flags & SE_SBINITIALIZED) |
094f7b69 | 878 | return selinux_cmp_sb_context(oldsb, newsb); |
5a552617 | 879 | |
c9180a57 EP |
880 | mutex_lock(&newsbsec->lock); |
881 | ||
882 | newsbsec->flags = oldsbsec->flags; | |
883 | ||
884 | newsbsec->sid = oldsbsec->sid; | |
885 | newsbsec->def_sid = oldsbsec->def_sid; | |
886 | newsbsec->behavior = oldsbsec->behavior; | |
887 | ||
888 | if (set_context) { | |
889 | u32 sid = oldsbsec->mntpoint_sid; | |
890 | ||
891 | if (!set_fscontext) | |
892 | newsbsec->sid = sid; | |
893 | if (!set_rootcontext) { | |
894 | struct inode *newinode = newsb->s_root->d_inode; | |
895 | struct inode_security_struct *newisec = newinode->i_security; | |
896 | newisec->sid = sid; | |
897 | } | |
898 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 899 | } |
c9180a57 EP |
900 | if (set_rootcontext) { |
901 | const struct inode *oldinode = oldsb->s_root->d_inode; | |
902 | const struct inode_security_struct *oldisec = oldinode->i_security; | |
903 | struct inode *newinode = newsb->s_root->d_inode; | |
904 | struct inode_security_struct *newisec = newinode->i_security; | |
1da177e4 | 905 | |
c9180a57 | 906 | newisec->sid = oldisec->sid; |
1da177e4 LT |
907 | } |
908 | ||
c9180a57 EP |
909 | sb_finish_set_opts(newsb); |
910 | mutex_unlock(&newsbsec->lock); | |
094f7b69 | 911 | return 0; |
c9180a57 EP |
912 | } |
913 | ||
2e1479d9 AB |
914 | static int selinux_parse_opts_str(char *options, |
915 | struct security_mnt_opts *opts) | |
c9180a57 | 916 | { |
e0007529 | 917 | char *p; |
c9180a57 EP |
918 | char *context = NULL, *defcontext = NULL; |
919 | char *fscontext = NULL, *rootcontext = NULL; | |
e0007529 | 920 | int rc, num_mnt_opts = 0; |
1da177e4 | 921 | |
e0007529 | 922 | opts->num_mnt_opts = 0; |
1da177e4 | 923 | |
c9180a57 EP |
924 | /* Standard string-based options. */ |
925 | while ((p = strsep(&options, "|")) != NULL) { | |
926 | int token; | |
927 | substring_t args[MAX_OPT_ARGS]; | |
1da177e4 | 928 | |
c9180a57 EP |
929 | if (!*p) |
930 | continue; | |
1da177e4 | 931 | |
c9180a57 | 932 | token = match_token(p, tokens, args); |
1da177e4 | 933 | |
c9180a57 EP |
934 | switch (token) { |
935 | case Opt_context: | |
936 | if (context || defcontext) { | |
937 | rc = -EINVAL; | |
938 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
939 | goto out_err; | |
940 | } | |
941 | context = match_strdup(&args[0]); | |
942 | if (!context) { | |
943 | rc = -ENOMEM; | |
944 | goto out_err; | |
945 | } | |
946 | break; | |
947 | ||
948 | case Opt_fscontext: | |
949 | if (fscontext) { | |
950 | rc = -EINVAL; | |
951 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
952 | goto out_err; | |
953 | } | |
954 | fscontext = match_strdup(&args[0]); | |
955 | if (!fscontext) { | |
956 | rc = -ENOMEM; | |
957 | goto out_err; | |
958 | } | |
959 | break; | |
960 | ||
961 | case Opt_rootcontext: | |
962 | if (rootcontext) { | |
963 | rc = -EINVAL; | |
964 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
965 | goto out_err; | |
966 | } | |
967 | rootcontext = match_strdup(&args[0]); | |
968 | if (!rootcontext) { | |
969 | rc = -ENOMEM; | |
970 | goto out_err; | |
971 | } | |
972 | break; | |
973 | ||
974 | case Opt_defcontext: | |
975 | if (context || defcontext) { | |
976 | rc = -EINVAL; | |
977 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
978 | goto out_err; | |
979 | } | |
980 | defcontext = match_strdup(&args[0]); | |
981 | if (!defcontext) { | |
982 | rc = -ENOMEM; | |
983 | goto out_err; | |
984 | } | |
985 | break; | |
11689d47 DQ |
986 | case Opt_labelsupport: |
987 | break; | |
c9180a57 EP |
988 | default: |
989 | rc = -EINVAL; | |
990 | printk(KERN_WARNING "SELinux: unknown mount option\n"); | |
991 | goto out_err; | |
1da177e4 | 992 | |
1da177e4 | 993 | } |
1da177e4 | 994 | } |
c9180a57 | 995 | |
e0007529 EP |
996 | rc = -ENOMEM; |
997 | opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); | |
998 | if (!opts->mnt_opts) | |
999 | goto out_err; | |
1000 | ||
1001 | opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); | |
1002 | if (!opts->mnt_opts_flags) { | |
1003 | kfree(opts->mnt_opts); | |
1004 | goto out_err; | |
1005 | } | |
1006 | ||
c9180a57 | 1007 | if (fscontext) { |
e0007529 EP |
1008 | opts->mnt_opts[num_mnt_opts] = fscontext; |
1009 | opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; | |
c9180a57 EP |
1010 | } |
1011 | if (context) { | |
e0007529 EP |
1012 | opts->mnt_opts[num_mnt_opts] = context; |
1013 | opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; | |
c9180a57 EP |
1014 | } |
1015 | if (rootcontext) { | |
e0007529 EP |
1016 | opts->mnt_opts[num_mnt_opts] = rootcontext; |
1017 | opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; | |
c9180a57 EP |
1018 | } |
1019 | if (defcontext) { | |
e0007529 EP |
1020 | opts->mnt_opts[num_mnt_opts] = defcontext; |
1021 | opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
1022 | } |
1023 | ||
e0007529 EP |
1024 | opts->num_mnt_opts = num_mnt_opts; |
1025 | return 0; | |
1026 | ||
c9180a57 EP |
1027 | out_err: |
1028 | kfree(context); | |
1029 | kfree(defcontext); | |
1030 | kfree(fscontext); | |
1031 | kfree(rootcontext); | |
1da177e4 LT |
1032 | return rc; |
1033 | } | |
e0007529 EP |
1034 | /* |
1035 | * string mount options parsing and call set the sbsec | |
1036 | */ | |
1037 | static int superblock_doinit(struct super_block *sb, void *data) | |
1038 | { | |
1039 | int rc = 0; | |
1040 | char *options = data; | |
1041 | struct security_mnt_opts opts; | |
1042 | ||
1043 | security_init_mnt_opts(&opts); | |
1044 | ||
1045 | if (!data) | |
1046 | goto out; | |
1047 | ||
1048 | BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); | |
1049 | ||
1050 | rc = selinux_parse_opts_str(options, &opts); | |
1051 | if (rc) | |
1052 | goto out_err; | |
1053 | ||
1054 | out: | |
649f6e77 | 1055 | rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); |
e0007529 EP |
1056 | |
1057 | out_err: | |
1058 | security_free_mnt_opts(&opts); | |
1059 | return rc; | |
1060 | } | |
1da177e4 | 1061 | |
3583a711 AB |
1062 | static void selinux_write_opts(struct seq_file *m, |
1063 | struct security_mnt_opts *opts) | |
2069f457 EP |
1064 | { |
1065 | int i; | |
1066 | char *prefix; | |
1067 | ||
1068 | for (i = 0; i < opts->num_mnt_opts; i++) { | |
11689d47 DQ |
1069 | char *has_comma; |
1070 | ||
1071 | if (opts->mnt_opts[i]) | |
1072 | has_comma = strchr(opts->mnt_opts[i], ','); | |
1073 | else | |
1074 | has_comma = NULL; | |
2069f457 EP |
1075 | |
1076 | switch (opts->mnt_opts_flags[i]) { | |
1077 | case CONTEXT_MNT: | |
1078 | prefix = CONTEXT_STR; | |
1079 | break; | |
1080 | case FSCONTEXT_MNT: | |
1081 | prefix = FSCONTEXT_STR; | |
1082 | break; | |
1083 | case ROOTCONTEXT_MNT: | |
1084 | prefix = ROOTCONTEXT_STR; | |
1085 | break; | |
1086 | case DEFCONTEXT_MNT: | |
1087 | prefix = DEFCONTEXT_STR; | |
1088 | break; | |
12f348b9 | 1089 | case SBLABEL_MNT: |
11689d47 DQ |
1090 | seq_putc(m, ','); |
1091 | seq_puts(m, LABELSUPP_STR); | |
1092 | continue; | |
2069f457 EP |
1093 | default: |
1094 | BUG(); | |
a35c6c83 | 1095 | return; |
2069f457 EP |
1096 | }; |
1097 | /* we need a comma before each option */ | |
1098 | seq_putc(m, ','); | |
1099 | seq_puts(m, prefix); | |
1100 | if (has_comma) | |
1101 | seq_putc(m, '\"'); | |
1102 | seq_puts(m, opts->mnt_opts[i]); | |
1103 | if (has_comma) | |
1104 | seq_putc(m, '\"'); | |
1105 | } | |
1106 | } | |
1107 | ||
1108 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1109 | { | |
1110 | struct security_mnt_opts opts; | |
1111 | int rc; | |
1112 | ||
1113 | rc = selinux_get_mnt_opts(sb, &opts); | |
383795c2 EP |
1114 | if (rc) { |
1115 | /* before policy load we may get EINVAL, don't show anything */ | |
1116 | if (rc == -EINVAL) | |
1117 | rc = 0; | |
2069f457 | 1118 | return rc; |
383795c2 | 1119 | } |
2069f457 EP |
1120 | |
1121 | selinux_write_opts(m, &opts); | |
1122 | ||
1123 | security_free_mnt_opts(&opts); | |
1124 | ||
1125 | return rc; | |
1126 | } | |
1127 | ||
1da177e4 LT |
1128 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1129 | { | |
1130 | switch (mode & S_IFMT) { | |
1131 | case S_IFSOCK: | |
1132 | return SECCLASS_SOCK_FILE; | |
1133 | case S_IFLNK: | |
1134 | return SECCLASS_LNK_FILE; | |
1135 | case S_IFREG: | |
1136 | return SECCLASS_FILE; | |
1137 | case S_IFBLK: | |
1138 | return SECCLASS_BLK_FILE; | |
1139 | case S_IFDIR: | |
1140 | return SECCLASS_DIR; | |
1141 | case S_IFCHR: | |
1142 | return SECCLASS_CHR_FILE; | |
1143 | case S_IFIFO: | |
1144 | return SECCLASS_FIFO_FILE; | |
1145 | ||
1146 | } | |
1147 | ||
1148 | return SECCLASS_FILE; | |
1149 | } | |
1150 | ||
13402580 JM |
1151 | static inline int default_protocol_stream(int protocol) |
1152 | { | |
1153 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1154 | } | |
1155 | ||
1156 | static inline int default_protocol_dgram(int protocol) | |
1157 | { | |
1158 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1159 | } | |
1160 | ||
1da177e4 LT |
1161 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1162 | { | |
1163 | switch (family) { | |
1164 | case PF_UNIX: | |
1165 | switch (type) { | |
1166 | case SOCK_STREAM: | |
1167 | case SOCK_SEQPACKET: | |
1168 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1169 | case SOCK_DGRAM: | |
1170 | return SECCLASS_UNIX_DGRAM_SOCKET; | |
1171 | } | |
1172 | break; | |
1173 | case PF_INET: | |
1174 | case PF_INET6: | |
1175 | switch (type) { | |
1176 | case SOCK_STREAM: | |
13402580 JM |
1177 | if (default_protocol_stream(protocol)) |
1178 | return SECCLASS_TCP_SOCKET; | |
1179 | else | |
1180 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1181 | case SOCK_DGRAM: |
13402580 JM |
1182 | if (default_protocol_dgram(protocol)) |
1183 | return SECCLASS_UDP_SOCKET; | |
1184 | else | |
1185 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1186 | case SOCK_DCCP: |
1187 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1188 | default: |
1da177e4 LT |
1189 | return SECCLASS_RAWIP_SOCKET; |
1190 | } | |
1191 | break; | |
1192 | case PF_NETLINK: | |
1193 | switch (protocol) { | |
1194 | case NETLINK_ROUTE: | |
1195 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
1196 | case NETLINK_FIREWALL: | |
1197 | return SECCLASS_NETLINK_FIREWALL_SOCKET; | |
7f1fb60c | 1198 | case NETLINK_SOCK_DIAG: |
1da177e4 LT |
1199 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1200 | case NETLINK_NFLOG: | |
1201 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1202 | case NETLINK_XFRM: | |
1203 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1204 | case NETLINK_SELINUX: | |
1205 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
1206 | case NETLINK_AUDIT: | |
1207 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
1208 | case NETLINK_IP6_FW: | |
1209 | return SECCLASS_NETLINK_IP6FW_SOCKET; | |
1210 | case NETLINK_DNRTMSG: | |
1211 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1212 | case NETLINK_KOBJECT_UEVENT: |
1213 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
1da177e4 LT |
1214 | default: |
1215 | return SECCLASS_NETLINK_SOCKET; | |
1216 | } | |
1217 | case PF_PACKET: | |
1218 | return SECCLASS_PACKET_SOCKET; | |
1219 | case PF_KEY: | |
1220 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1221 | case PF_APPLETALK: |
1222 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1223 | } |
1224 | ||
1225 | return SECCLASS_SOCKET; | |
1226 | } | |
1227 | ||
1228 | #ifdef CONFIG_PROC_FS | |
8e6c9693 | 1229 | static int selinux_proc_get_sid(struct dentry *dentry, |
1da177e4 LT |
1230 | u16 tclass, |
1231 | u32 *sid) | |
1232 | { | |
8e6c9693 LAG |
1233 | int rc; |
1234 | char *buffer, *path; | |
1da177e4 | 1235 | |
828dfe1d | 1236 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1237 | if (!buffer) |
1238 | return -ENOMEM; | |
1239 | ||
8e6c9693 LAG |
1240 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1241 | if (IS_ERR(path)) | |
1242 | rc = PTR_ERR(path); | |
1243 | else { | |
1244 | /* each process gets a /proc/PID/ entry. Strip off the | |
1245 | * PID part to get a valid selinux labeling. | |
1246 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1247 | while (path[1] >= '0' && path[1] <= '9') { | |
1248 | path[1] = '/'; | |
1249 | path++; | |
1250 | } | |
1251 | rc = security_genfs_sid("proc", path, tclass, sid); | |
1da177e4 | 1252 | } |
1da177e4 LT |
1253 | free_page((unsigned long)buffer); |
1254 | return rc; | |
1255 | } | |
1256 | #else | |
8e6c9693 | 1257 | static int selinux_proc_get_sid(struct dentry *dentry, |
1da177e4 LT |
1258 | u16 tclass, |
1259 | u32 *sid) | |
1260 | { | |
1261 | return -EINVAL; | |
1262 | } | |
1263 | #endif | |
1264 | ||
1265 | /* The inode's security attributes must be initialized before first use. */ | |
1266 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1267 | { | |
1268 | struct superblock_security_struct *sbsec = NULL; | |
1269 | struct inode_security_struct *isec = inode->i_security; | |
1270 | u32 sid; | |
1271 | struct dentry *dentry; | |
1272 | #define INITCONTEXTLEN 255 | |
1273 | char *context = NULL; | |
1274 | unsigned len = 0; | |
1275 | int rc = 0; | |
1da177e4 LT |
1276 | |
1277 | if (isec->initialized) | |
1278 | goto out; | |
1279 | ||
23970741 | 1280 | mutex_lock(&isec->lock); |
1da177e4 | 1281 | if (isec->initialized) |
23970741 | 1282 | goto out_unlock; |
1da177e4 LT |
1283 | |
1284 | sbsec = inode->i_sb->s_security; | |
0d90a7ec | 1285 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1286 | /* Defer initialization until selinux_complete_init, |
1287 | after the initial policy is loaded and the security | |
1288 | server is ready to handle calls. */ | |
1289 | spin_lock(&sbsec->isec_lock); | |
1290 | if (list_empty(&isec->list)) | |
1291 | list_add(&isec->list, &sbsec->isec_head); | |
1292 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1293 | goto out_unlock; |
1da177e4 LT |
1294 | } |
1295 | ||
1296 | switch (sbsec->behavior) { | |
eb9ae686 DQ |
1297 | case SECURITY_FS_USE_NATIVE: |
1298 | break; | |
1da177e4 LT |
1299 | case SECURITY_FS_USE_XATTR: |
1300 | if (!inode->i_op->getxattr) { | |
1301 | isec->sid = sbsec->def_sid; | |
1302 | break; | |
1303 | } | |
1304 | ||
1305 | /* Need a dentry, since the xattr API requires one. | |
1306 | Life would be simpler if we could just pass the inode. */ | |
1307 | if (opt_dentry) { | |
1308 | /* Called from d_instantiate or d_splice_alias. */ | |
1309 | dentry = dget(opt_dentry); | |
1310 | } else { | |
1311 | /* Called from selinux_complete_init, try to find a dentry. */ | |
1312 | dentry = d_find_alias(inode); | |
1313 | } | |
1314 | if (!dentry) { | |
df7f54c0 EP |
1315 | /* |
1316 | * this is can be hit on boot when a file is accessed | |
1317 | * before the policy is loaded. When we load policy we | |
1318 | * may find inodes that have no dentry on the | |
1319 | * sbsec->isec_head list. No reason to complain as these | |
1320 | * will get fixed up the next time we go through | |
1321 | * inode_doinit with a dentry, before these inodes could | |
1322 | * be used again by userspace. | |
1323 | */ | |
23970741 | 1324 | goto out_unlock; |
1da177e4 LT |
1325 | } |
1326 | ||
1327 | len = INITCONTEXTLEN; | |
4cb912f1 | 1328 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1329 | if (!context) { |
1330 | rc = -ENOMEM; | |
1331 | dput(dentry); | |
23970741 | 1332 | goto out_unlock; |
1da177e4 | 1333 | } |
4cb912f1 | 1334 | context[len] = '\0'; |
1da177e4 LT |
1335 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, |
1336 | context, len); | |
1337 | if (rc == -ERANGE) { | |
314dabb8 JM |
1338 | kfree(context); |
1339 | ||
1da177e4 LT |
1340 | /* Need a larger buffer. Query for the right size. */ |
1341 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, | |
1342 | NULL, 0); | |
1343 | if (rc < 0) { | |
1344 | dput(dentry); | |
23970741 | 1345 | goto out_unlock; |
1da177e4 | 1346 | } |
1da177e4 | 1347 | len = rc; |
4cb912f1 | 1348 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1349 | if (!context) { |
1350 | rc = -ENOMEM; | |
1351 | dput(dentry); | |
23970741 | 1352 | goto out_unlock; |
1da177e4 | 1353 | } |
4cb912f1 | 1354 | context[len] = '\0'; |
1da177e4 LT |
1355 | rc = inode->i_op->getxattr(dentry, |
1356 | XATTR_NAME_SELINUX, | |
1357 | context, len); | |
1358 | } | |
1359 | dput(dentry); | |
1360 | if (rc < 0) { | |
1361 | if (rc != -ENODATA) { | |
744ba35e | 1362 | printk(KERN_WARNING "SELinux: %s: getxattr returned " |
dd6f953a | 1363 | "%d for dev=%s ino=%ld\n", __func__, |
1da177e4 LT |
1364 | -rc, inode->i_sb->s_id, inode->i_ino); |
1365 | kfree(context); | |
23970741 | 1366 | goto out_unlock; |
1da177e4 LT |
1367 | } |
1368 | /* Map ENODATA to the default file SID */ | |
1369 | sid = sbsec->def_sid; | |
1370 | rc = 0; | |
1371 | } else { | |
f5c1d5b2 | 1372 | rc = security_context_to_sid_default(context, rc, &sid, |
869ab514 SS |
1373 | sbsec->def_sid, |
1374 | GFP_NOFS); | |
1da177e4 | 1375 | if (rc) { |
4ba0a8ad EP |
1376 | char *dev = inode->i_sb->s_id; |
1377 | unsigned long ino = inode->i_ino; | |
1378 | ||
1379 | if (rc == -EINVAL) { | |
1380 | if (printk_ratelimit()) | |
1381 | printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " | |
1382 | "context=%s. This indicates you may need to relabel the inode or the " | |
1383 | "filesystem in question.\n", ino, dev, context); | |
1384 | } else { | |
1385 | printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " | |
1386 | "returned %d for dev=%s ino=%ld\n", | |
1387 | __func__, context, -rc, dev, ino); | |
1388 | } | |
1da177e4 LT |
1389 | kfree(context); |
1390 | /* Leave with the unlabeled SID */ | |
1391 | rc = 0; | |
1392 | break; | |
1393 | } | |
1394 | } | |
1395 | kfree(context); | |
1396 | isec->sid = sid; | |
1397 | break; | |
1398 | case SECURITY_FS_USE_TASK: | |
1399 | isec->sid = isec->task_sid; | |
1400 | break; | |
1401 | case SECURITY_FS_USE_TRANS: | |
1402 | /* Default to the fs SID. */ | |
1403 | isec->sid = sbsec->sid; | |
1404 | ||
1405 | /* Try to obtain a transition SID. */ | |
1406 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
652bb9b0 EP |
1407 | rc = security_transition_sid(isec->task_sid, sbsec->sid, |
1408 | isec->sclass, NULL, &sid); | |
1da177e4 | 1409 | if (rc) |
23970741 | 1410 | goto out_unlock; |
1da177e4 LT |
1411 | isec->sid = sid; |
1412 | break; | |
c312feb2 EP |
1413 | case SECURITY_FS_USE_MNTPOINT: |
1414 | isec->sid = sbsec->mntpoint_sid; | |
1415 | break; | |
1da177e4 | 1416 | default: |
c312feb2 | 1417 | /* Default to the fs superblock SID. */ |
1da177e4 LT |
1418 | isec->sid = sbsec->sid; |
1419 | ||
0d90a7ec | 1420 | if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { |
f64410ec PM |
1421 | /* We must have a dentry to determine the label on |
1422 | * procfs inodes */ | |
1423 | if (opt_dentry) | |
1424 | /* Called from d_instantiate or | |
1425 | * d_splice_alias. */ | |
1426 | dentry = dget(opt_dentry); | |
1427 | else | |
1428 | /* Called from selinux_complete_init, try to | |
1429 | * find a dentry. */ | |
1430 | dentry = d_find_alias(inode); | |
1431 | /* | |
1432 | * This 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 | |
1436 | * these will get fixed up the next time we go through | |
1437 | * inode_doinit() with a dentry, before these inodes | |
1438 | * could be used again by userspace. | |
1439 | */ | |
1440 | if (!dentry) | |
1441 | goto out_unlock; | |
1442 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1443 | rc = selinux_proc_get_sid(dentry, isec->sclass, &sid); | |
1444 | dput(dentry); | |
1445 | if (rc) | |
1446 | goto out_unlock; | |
1447 | isec->sid = sid; | |
1da177e4 LT |
1448 | } |
1449 | break; | |
1450 | } | |
1451 | ||
1452 | isec->initialized = 1; | |
1453 | ||
23970741 EP |
1454 | out_unlock: |
1455 | mutex_unlock(&isec->lock); | |
1da177e4 LT |
1456 | out: |
1457 | if (isec->sclass == SECCLASS_FILE) | |
1458 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1da177e4 LT |
1459 | return rc; |
1460 | } | |
1461 | ||
1462 | /* Convert a Linux signal to an access vector. */ | |
1463 | static inline u32 signal_to_av(int sig) | |
1464 | { | |
1465 | u32 perm = 0; | |
1466 | ||
1467 | switch (sig) { | |
1468 | case SIGCHLD: | |
1469 | /* Commonly granted from child to parent. */ | |
1470 | perm = PROCESS__SIGCHLD; | |
1471 | break; | |
1472 | case SIGKILL: | |
1473 | /* Cannot be caught or ignored */ | |
1474 | perm = PROCESS__SIGKILL; | |
1475 | break; | |
1476 | case SIGSTOP: | |
1477 | /* Cannot be caught or ignored */ | |
1478 | perm = PROCESS__SIGSTOP; | |
1479 | break; | |
1480 | default: | |
1481 | /* All other signals. */ | |
1482 | perm = PROCESS__SIGNAL; | |
1483 | break; | |
1484 | } | |
1485 | ||
1486 | return perm; | |
1487 | } | |
1488 | ||
d84f4f99 DH |
1489 | /* |
1490 | * Check permission between a pair of credentials | |
1491 | * fork check, ptrace check, etc. | |
1492 | */ | |
1493 | static int cred_has_perm(const struct cred *actor, | |
1494 | const struct cred *target, | |
1495 | u32 perms) | |
1496 | { | |
1497 | u32 asid = cred_sid(actor), tsid = cred_sid(target); | |
1498 | ||
1499 | return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); | |
1500 | } | |
1501 | ||
275bb41e | 1502 | /* |
88e67f3b | 1503 | * Check permission between a pair of tasks, e.g. signal checks, |
275bb41e DH |
1504 | * fork check, ptrace check, etc. |
1505 | * tsk1 is the actor and tsk2 is the target | |
3b11a1de | 1506 | * - this uses the default subjective creds of tsk1 |
275bb41e DH |
1507 | */ |
1508 | static int task_has_perm(const struct task_struct *tsk1, | |
1509 | const struct task_struct *tsk2, | |
1da177e4 LT |
1510 | u32 perms) |
1511 | { | |
275bb41e DH |
1512 | const struct task_security_struct *__tsec1, *__tsec2; |
1513 | u32 sid1, sid2; | |
1da177e4 | 1514 | |
275bb41e DH |
1515 | rcu_read_lock(); |
1516 | __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; | |
1517 | __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; | |
1518 | rcu_read_unlock(); | |
1519 | return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); | |
1da177e4 LT |
1520 | } |
1521 | ||
3b11a1de DH |
1522 | /* |
1523 | * Check permission between current and another task, e.g. signal checks, | |
1524 | * fork check, ptrace check, etc. | |
1525 | * current is the actor and tsk2 is the target | |
1526 | * - this uses current's subjective creds | |
1527 | */ | |
1528 | static int current_has_perm(const struct task_struct *tsk, | |
1529 | u32 perms) | |
1530 | { | |
1531 | u32 sid, tsid; | |
1532 | ||
1533 | sid = current_sid(); | |
1534 | tsid = task_sid(tsk); | |
1535 | return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); | |
1536 | } | |
1537 | ||
b68e418c SS |
1538 | #if CAP_LAST_CAP > 63 |
1539 | #error Fix SELinux to handle capabilities > 63. | |
1540 | #endif | |
1541 | ||
1da177e4 | 1542 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1543 | static int cred_has_capability(const struct cred *cred, |
06112163 | 1544 | int cap, int audit) |
1da177e4 | 1545 | { |
2bf49690 | 1546 | struct common_audit_data ad; |
06112163 | 1547 | struct av_decision avd; |
b68e418c | 1548 | u16 sclass; |
3699c53c | 1549 | u32 sid = cred_sid(cred); |
b68e418c | 1550 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1551 | int rc; |
1da177e4 | 1552 | |
50c205f5 | 1553 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1554 | ad.u.cap = cap; |
1555 | ||
b68e418c SS |
1556 | switch (CAP_TO_INDEX(cap)) { |
1557 | case 0: | |
1558 | sclass = SECCLASS_CAPABILITY; | |
1559 | break; | |
1560 | case 1: | |
1561 | sclass = SECCLASS_CAPABILITY2; | |
1562 | break; | |
1563 | default: | |
1564 | printk(KERN_ERR | |
1565 | "SELinux: out of range capability %d\n", cap); | |
1566 | BUG(); | |
a35c6c83 | 1567 | return -EINVAL; |
b68e418c | 1568 | } |
06112163 | 1569 | |
275bb41e | 1570 | rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); |
9ade0cf4 | 1571 | if (audit == SECURITY_CAP_AUDIT) { |
ab354062 | 1572 | int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); |
9ade0cf4 EP |
1573 | if (rc2) |
1574 | return rc2; | |
1575 | } | |
06112163 | 1576 | return rc; |
1da177e4 LT |
1577 | } |
1578 | ||
1579 | /* Check whether a task is allowed to use a system operation. */ | |
1580 | static int task_has_system(struct task_struct *tsk, | |
1581 | u32 perms) | |
1582 | { | |
275bb41e | 1583 | u32 sid = task_sid(tsk); |
1da177e4 | 1584 | |
275bb41e | 1585 | return avc_has_perm(sid, SECINITSID_KERNEL, |
1da177e4 LT |
1586 | SECCLASS_SYSTEM, perms, NULL); |
1587 | } | |
1588 | ||
1589 | /* Check whether a task has a particular permission to an inode. | |
1590 | The 'adp' parameter is optional and allows other audit | |
1591 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1592 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1593 | struct inode *inode, |
1594 | u32 perms, | |
19e49834 | 1595 | struct common_audit_data *adp) |
1da177e4 | 1596 | { |
1da177e4 | 1597 | struct inode_security_struct *isec; |
275bb41e | 1598 | u32 sid; |
1da177e4 | 1599 | |
e0e81739 DH |
1600 | validate_creds(cred); |
1601 | ||
828dfe1d | 1602 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1603 | return 0; |
1604 | ||
88e67f3b | 1605 | sid = cred_sid(cred); |
1da177e4 LT |
1606 | isec = inode->i_security; |
1607 | ||
19e49834 | 1608 | return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); |
1da177e4 LT |
1609 | } |
1610 | ||
1611 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1612 | the dentry to help the auditing code to more easily generate the | |
1613 | pathname if needed. */ | |
88e67f3b | 1614 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1615 | struct dentry *dentry, |
1616 | u32 av) | |
1617 | { | |
1618 | struct inode *inode = dentry->d_inode; | |
2bf49690 | 1619 | struct common_audit_data ad; |
88e67f3b | 1620 | |
50c205f5 | 1621 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1622 | ad.u.dentry = dentry; |
19e49834 | 1623 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1624 | } |
1625 | ||
1626 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1627 | the path to help the auditing code to more easily generate the | |
1628 | pathname if needed. */ | |
1629 | static inline int path_has_perm(const struct cred *cred, | |
1630 | struct path *path, | |
1631 | u32 av) | |
1632 | { | |
1633 | struct inode *inode = path->dentry->d_inode; | |
1634 | struct common_audit_data ad; | |
1635 | ||
50c205f5 | 1636 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1637 | ad.u.path = *path; |
19e49834 | 1638 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1639 | } |
1640 | ||
13f8e981 DH |
1641 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1642 | static inline int file_path_has_perm(const struct cred *cred, | |
1643 | struct file *file, | |
1644 | u32 av) | |
1645 | { | |
1646 | struct common_audit_data ad; | |
1647 | ||
1648 | ad.type = LSM_AUDIT_DATA_PATH; | |
1649 | ad.u.path = file->f_path; | |
19e49834 | 1650 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1651 | } |
1652 | ||
1da177e4 LT |
1653 | /* Check whether a task can use an open file descriptor to |
1654 | access an inode in a given way. Check access to the | |
1655 | descriptor itself, and then use dentry_has_perm to | |
1656 | check a particular permission to the file. | |
1657 | Access to the descriptor is implicitly granted if it | |
1658 | has the same SID as the process. If av is zero, then | |
1659 | access to the file is not checked, e.g. for cases | |
1660 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1661 | static int file_has_perm(const struct cred *cred, |
1662 | struct file *file, | |
1663 | u32 av) | |
1da177e4 | 1664 | { |
1da177e4 | 1665 | struct file_security_struct *fsec = file->f_security; |
496ad9aa | 1666 | struct inode *inode = file_inode(file); |
2bf49690 | 1667 | struct common_audit_data ad; |
88e67f3b | 1668 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1669 | int rc; |
1670 | ||
50c205f5 | 1671 | ad.type = LSM_AUDIT_DATA_PATH; |
f48b7399 | 1672 | ad.u.path = file->f_path; |
1da177e4 | 1673 | |
275bb41e DH |
1674 | if (sid != fsec->sid) { |
1675 | rc = avc_has_perm(sid, fsec->sid, | |
1da177e4 LT |
1676 | SECCLASS_FD, |
1677 | FD__USE, | |
1678 | &ad); | |
1679 | if (rc) | |
88e67f3b | 1680 | goto out; |
1da177e4 LT |
1681 | } |
1682 | ||
1683 | /* av is zero if only checking access to the descriptor. */ | |
88e67f3b | 1684 | rc = 0; |
1da177e4 | 1685 | if (av) |
19e49834 | 1686 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1687 | |
88e67f3b DH |
1688 | out: |
1689 | return rc; | |
1da177e4 LT |
1690 | } |
1691 | ||
1692 | /* Check whether a task can create a file. */ | |
1693 | static int may_create(struct inode *dir, | |
1694 | struct dentry *dentry, | |
1695 | u16 tclass) | |
1696 | { | |
5fb49870 | 1697 | const struct task_security_struct *tsec = current_security(); |
1da177e4 LT |
1698 | struct inode_security_struct *dsec; |
1699 | struct superblock_security_struct *sbsec; | |
275bb41e | 1700 | u32 sid, newsid; |
2bf49690 | 1701 | struct common_audit_data ad; |
1da177e4 LT |
1702 | int rc; |
1703 | ||
1da177e4 LT |
1704 | dsec = dir->i_security; |
1705 | sbsec = dir->i_sb->s_security; | |
1706 | ||
275bb41e DH |
1707 | sid = tsec->sid; |
1708 | newsid = tsec->create_sid; | |
1709 | ||
50c205f5 | 1710 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1711 | ad.u.dentry = dentry; |
1da177e4 | 1712 | |
275bb41e | 1713 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
1714 | DIR__ADD_NAME | DIR__SEARCH, |
1715 | &ad); | |
1716 | if (rc) | |
1717 | return rc; | |
1718 | ||
12f348b9 | 1719 | if (!newsid || !(sbsec->flags & SBLABEL_MNT)) { |
cb1e922f EP |
1720 | rc = security_transition_sid(sid, dsec->sid, tclass, |
1721 | &dentry->d_name, &newsid); | |
1da177e4 LT |
1722 | if (rc) |
1723 | return rc; | |
1724 | } | |
1725 | ||
275bb41e | 1726 | rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); |
1da177e4 LT |
1727 | if (rc) |
1728 | return rc; | |
1729 | ||
1730 | return avc_has_perm(newsid, sbsec->sid, | |
1731 | SECCLASS_FILESYSTEM, | |
1732 | FILESYSTEM__ASSOCIATE, &ad); | |
1733 | } | |
1734 | ||
4eb582cf ML |
1735 | /* Check whether a task can create a key. */ |
1736 | static int may_create_key(u32 ksid, | |
1737 | struct task_struct *ctx) | |
1738 | { | |
275bb41e | 1739 | u32 sid = task_sid(ctx); |
4eb582cf | 1740 | |
275bb41e | 1741 | return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); |
4eb582cf ML |
1742 | } |
1743 | ||
828dfe1d EP |
1744 | #define MAY_LINK 0 |
1745 | #define MAY_UNLINK 1 | |
1746 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1747 | |
1748 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1749 | static int may_link(struct inode *dir, | |
1750 | struct dentry *dentry, | |
1751 | int kind) | |
1752 | ||
1753 | { | |
1da177e4 | 1754 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 1755 | struct common_audit_data ad; |
275bb41e | 1756 | u32 sid = current_sid(); |
1da177e4 LT |
1757 | u32 av; |
1758 | int rc; | |
1759 | ||
1da177e4 LT |
1760 | dsec = dir->i_security; |
1761 | isec = dentry->d_inode->i_security; | |
1762 | ||
50c205f5 | 1763 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1764 | ad.u.dentry = dentry; |
1da177e4 LT |
1765 | |
1766 | av = DIR__SEARCH; | |
1767 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
275bb41e | 1768 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
1769 | if (rc) |
1770 | return rc; | |
1771 | ||
1772 | switch (kind) { | |
1773 | case MAY_LINK: | |
1774 | av = FILE__LINK; | |
1775 | break; | |
1776 | case MAY_UNLINK: | |
1777 | av = FILE__UNLINK; | |
1778 | break; | |
1779 | case MAY_RMDIR: | |
1780 | av = DIR__RMDIR; | |
1781 | break; | |
1782 | default: | |
744ba35e EP |
1783 | printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", |
1784 | __func__, kind); | |
1da177e4 LT |
1785 | return 0; |
1786 | } | |
1787 | ||
275bb41e | 1788 | rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); |
1da177e4 LT |
1789 | return rc; |
1790 | } | |
1791 | ||
1792 | static inline int may_rename(struct inode *old_dir, | |
1793 | struct dentry *old_dentry, | |
1794 | struct inode *new_dir, | |
1795 | struct dentry *new_dentry) | |
1796 | { | |
1da177e4 | 1797 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 1798 | struct common_audit_data ad; |
275bb41e | 1799 | u32 sid = current_sid(); |
1da177e4 LT |
1800 | u32 av; |
1801 | int old_is_dir, new_is_dir; | |
1802 | int rc; | |
1803 | ||
1da177e4 LT |
1804 | old_dsec = old_dir->i_security; |
1805 | old_isec = old_dentry->d_inode->i_security; | |
1806 | old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); | |
1807 | new_dsec = new_dir->i_security; | |
1808 | ||
50c205f5 | 1809 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 1810 | |
a269434d | 1811 | ad.u.dentry = old_dentry; |
275bb41e | 1812 | rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
1813 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
1814 | if (rc) | |
1815 | return rc; | |
275bb41e | 1816 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
1817 | old_isec->sclass, FILE__RENAME, &ad); |
1818 | if (rc) | |
1819 | return rc; | |
1820 | if (old_is_dir && new_dir != old_dir) { | |
275bb41e | 1821 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
1822 | old_isec->sclass, DIR__REPARENT, &ad); |
1823 | if (rc) | |
1824 | return rc; | |
1825 | } | |
1826 | ||
a269434d | 1827 | ad.u.dentry = new_dentry; |
1da177e4 LT |
1828 | av = DIR__ADD_NAME | DIR__SEARCH; |
1829 | if (new_dentry->d_inode) | |
1830 | av |= DIR__REMOVE_NAME; | |
275bb41e | 1831 | rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
1832 | if (rc) |
1833 | return rc; | |
1834 | if (new_dentry->d_inode) { | |
1835 | new_isec = new_dentry->d_inode->i_security; | |
1836 | new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); | |
275bb41e | 1837 | rc = avc_has_perm(sid, new_isec->sid, |
1da177e4 LT |
1838 | new_isec->sclass, |
1839 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1840 | if (rc) | |
1841 | return rc; | |
1842 | } | |
1843 | ||
1844 | return 0; | |
1845 | } | |
1846 | ||
1847 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 1848 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
1849 | struct super_block *sb, |
1850 | u32 perms, | |
2bf49690 | 1851 | struct common_audit_data *ad) |
1da177e4 | 1852 | { |
1da177e4 | 1853 | struct superblock_security_struct *sbsec; |
88e67f3b | 1854 | u32 sid = cred_sid(cred); |
1da177e4 | 1855 | |
1da177e4 | 1856 | sbsec = sb->s_security; |
275bb41e | 1857 | return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); |
1da177e4 LT |
1858 | } |
1859 | ||
1860 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1861 | static inline u32 file_mask_to_av(int mode, int mask) | |
1862 | { | |
1863 | u32 av = 0; | |
1864 | ||
dba19c60 | 1865 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
1866 | if (mask & MAY_EXEC) |
1867 | av |= FILE__EXECUTE; | |
1868 | if (mask & MAY_READ) | |
1869 | av |= FILE__READ; | |
1870 | ||
1871 | if (mask & MAY_APPEND) | |
1872 | av |= FILE__APPEND; | |
1873 | else if (mask & MAY_WRITE) | |
1874 | av |= FILE__WRITE; | |
1875 | ||
1876 | } else { | |
1877 | if (mask & MAY_EXEC) | |
1878 | av |= DIR__SEARCH; | |
1879 | if (mask & MAY_WRITE) | |
1880 | av |= DIR__WRITE; | |
1881 | if (mask & MAY_READ) | |
1882 | av |= DIR__READ; | |
1883 | } | |
1884 | ||
1885 | return av; | |
1886 | } | |
1887 | ||
8b6a5a37 EP |
1888 | /* Convert a Linux file to an access vector. */ |
1889 | static inline u32 file_to_av(struct file *file) | |
1890 | { | |
1891 | u32 av = 0; | |
1892 | ||
1893 | if (file->f_mode & FMODE_READ) | |
1894 | av |= FILE__READ; | |
1895 | if (file->f_mode & FMODE_WRITE) { | |
1896 | if (file->f_flags & O_APPEND) | |
1897 | av |= FILE__APPEND; | |
1898 | else | |
1899 | av |= FILE__WRITE; | |
1900 | } | |
1901 | if (!av) { | |
1902 | /* | |
1903 | * Special file opened with flags 3 for ioctl-only use. | |
1904 | */ | |
1905 | av = FILE__IOCTL; | |
1906 | } | |
1907 | ||
1908 | return av; | |
1909 | } | |
1910 | ||
b0c636b9 | 1911 | /* |
8b6a5a37 | 1912 | * Convert a file to an access vector and include the correct open |
b0c636b9 EP |
1913 | * open permission. |
1914 | */ | |
8b6a5a37 | 1915 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 1916 | { |
8b6a5a37 | 1917 | u32 av = file_to_av(file); |
b0c636b9 | 1918 | |
49b7b8de EP |
1919 | if (selinux_policycap_openperm) |
1920 | av |= FILE__OPEN; | |
1921 | ||
b0c636b9 EP |
1922 | return av; |
1923 | } | |
1924 | ||
1da177e4 LT |
1925 | /* Hook functions begin here. */ |
1926 | ||
9e48858f | 1927 | static int selinux_ptrace_access_check(struct task_struct *child, |
5cd9c58f | 1928 | unsigned int mode) |
1da177e4 | 1929 | { |
1da177e4 LT |
1930 | int rc; |
1931 | ||
9e48858f | 1932 | rc = cap_ptrace_access_check(child, mode); |
1da177e4 LT |
1933 | if (rc) |
1934 | return rc; | |
1935 | ||
69f594a3 | 1936 | if (mode & PTRACE_MODE_READ) { |
275bb41e DH |
1937 | u32 sid = current_sid(); |
1938 | u32 csid = task_sid(child); | |
1939 | return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 SS |
1940 | } |
1941 | ||
3b11a1de | 1942 | return current_has_perm(child, PROCESS__PTRACE); |
5cd9c58f DH |
1943 | } |
1944 | ||
1945 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
1946 | { | |
1947 | int rc; | |
1948 | ||
200ac532 | 1949 | rc = cap_ptrace_traceme(parent); |
5cd9c58f DH |
1950 | if (rc) |
1951 | return rc; | |
1952 | ||
1953 | return task_has_perm(parent, current, PROCESS__PTRACE); | |
1da177e4 LT |
1954 | } |
1955 | ||
1956 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 1957 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 LT |
1958 | { |
1959 | int error; | |
1960 | ||
3b11a1de | 1961 | error = current_has_perm(target, PROCESS__GETCAP); |
1da177e4 LT |
1962 | if (error) |
1963 | return error; | |
1964 | ||
200ac532 | 1965 | return cap_capget(target, effective, inheritable, permitted); |
1da177e4 LT |
1966 | } |
1967 | ||
d84f4f99 DH |
1968 | static int selinux_capset(struct cred *new, const struct cred *old, |
1969 | const kernel_cap_t *effective, | |
1970 | const kernel_cap_t *inheritable, | |
1971 | const kernel_cap_t *permitted) | |
1da177e4 LT |
1972 | { |
1973 | int error; | |
1974 | ||
200ac532 | 1975 | error = cap_capset(new, old, |
d84f4f99 | 1976 | effective, inheritable, permitted); |
1da177e4 LT |
1977 | if (error) |
1978 | return error; | |
1979 | ||
d84f4f99 | 1980 | return cred_has_perm(old, new, PROCESS__SETCAP); |
1da177e4 LT |
1981 | } |
1982 | ||
5626d3e8 JM |
1983 | /* |
1984 | * (This comment used to live with the selinux_task_setuid hook, | |
1985 | * which was removed). | |
1986 | * | |
1987 | * Since setuid only affects the current process, and since the SELinux | |
1988 | * controls are not based on the Linux identity attributes, SELinux does not | |
1989 | * need to control this operation. However, SELinux does control the use of | |
1990 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
1991 | */ | |
1992 | ||
6a9de491 EP |
1993 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
1994 | int cap, int audit) | |
1da177e4 LT |
1995 | { |
1996 | int rc; | |
1997 | ||
6a9de491 | 1998 | rc = cap_capable(cred, ns, cap, audit); |
1da177e4 LT |
1999 | if (rc) |
2000 | return rc; | |
2001 | ||
6a9de491 | 2002 | return cred_has_capability(cred, cap, audit); |
1da177e4 LT |
2003 | } |
2004 | ||
1da177e4 LT |
2005 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
2006 | { | |
88e67f3b | 2007 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2008 | int rc = 0; |
2009 | ||
2010 | if (!sb) | |
2011 | return 0; | |
2012 | ||
2013 | switch (cmds) { | |
828dfe1d EP |
2014 | case Q_SYNC: |
2015 | case Q_QUOTAON: | |
2016 | case Q_QUOTAOFF: | |
2017 | case Q_SETINFO: | |
2018 | case Q_SETQUOTA: | |
88e67f3b | 2019 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
2020 | break; |
2021 | case Q_GETFMT: | |
2022 | case Q_GETINFO: | |
2023 | case Q_GETQUOTA: | |
88e67f3b | 2024 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
2025 | break; |
2026 | default: | |
2027 | rc = 0; /* let the kernel handle invalid cmds */ | |
2028 | break; | |
1da177e4 LT |
2029 | } |
2030 | return rc; | |
2031 | } | |
2032 | ||
2033 | static int selinux_quota_on(struct dentry *dentry) | |
2034 | { | |
88e67f3b DH |
2035 | const struct cred *cred = current_cred(); |
2036 | ||
2875fa00 | 2037 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
2038 | } |
2039 | ||
12b3052c | 2040 | static int selinux_syslog(int type) |
1da177e4 LT |
2041 | { |
2042 | int rc; | |
2043 | ||
1da177e4 | 2044 | switch (type) { |
d78ca3cd KC |
2045 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2046 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
828dfe1d EP |
2047 | rc = task_has_system(current, SYSTEM__SYSLOG_READ); |
2048 | break; | |
d78ca3cd KC |
2049 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2050 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2051 | /* Set level of messages printed to console */ | |
2052 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
828dfe1d EP |
2053 | rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); |
2054 | break; | |
d78ca3cd KC |
2055 | case SYSLOG_ACTION_CLOSE: /* Close log */ |
2056 | case SYSLOG_ACTION_OPEN: /* Open log */ | |
2057 | case SYSLOG_ACTION_READ: /* Read from log */ | |
2058 | case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ | |
2059 | case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ | |
828dfe1d EP |
2060 | default: |
2061 | rc = task_has_system(current, SYSTEM__SYSLOG_MOD); | |
2062 | break; | |
1da177e4 LT |
2063 | } |
2064 | return rc; | |
2065 | } | |
2066 | ||
2067 | /* | |
2068 | * Check that a process has enough memory to allocate a new virtual | |
2069 | * mapping. 0 means there is enough memory for the allocation to | |
2070 | * succeed and -ENOMEM implies there is not. | |
2071 | * | |
1da177e4 LT |
2072 | * Do not audit the selinux permission check, as this is applied to all |
2073 | * processes that allocate mappings. | |
2074 | */ | |
34b4e4aa | 2075 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2076 | { |
2077 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2078 | |
6a9de491 | 2079 | rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN, |
3699c53c | 2080 | SECURITY_CAP_NOAUDIT); |
1da177e4 LT |
2081 | if (rc == 0) |
2082 | cap_sys_admin = 1; | |
2083 | ||
34b4e4aa | 2084 | return __vm_enough_memory(mm, pages, cap_sys_admin); |
1da177e4 LT |
2085 | } |
2086 | ||
2087 | /* binprm security operations */ | |
2088 | ||
a6f76f23 | 2089 | static int selinux_bprm_set_creds(struct linux_binprm *bprm) |
1da177e4 | 2090 | { |
a6f76f23 DH |
2091 | const struct task_security_struct *old_tsec; |
2092 | struct task_security_struct *new_tsec; | |
1da177e4 | 2093 | struct inode_security_struct *isec; |
2bf49690 | 2094 | struct common_audit_data ad; |
496ad9aa | 2095 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2096 | int rc; |
2097 | ||
200ac532 | 2098 | rc = cap_bprm_set_creds(bprm); |
1da177e4 LT |
2099 | if (rc) |
2100 | return rc; | |
2101 | ||
a6f76f23 DH |
2102 | /* SELinux context only depends on initial program or script and not |
2103 | * the script interpreter */ | |
2104 | if (bprm->cred_prepared) | |
1da177e4 LT |
2105 | return 0; |
2106 | ||
a6f76f23 DH |
2107 | old_tsec = current_security(); |
2108 | new_tsec = bprm->cred->security; | |
1da177e4 LT |
2109 | isec = inode->i_security; |
2110 | ||
2111 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2112 | new_tsec->sid = old_tsec->sid; |
2113 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2114 | |
28eba5bf | 2115 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2116 | new_tsec->create_sid = 0; |
2117 | new_tsec->keycreate_sid = 0; | |
2118 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2119 | |
a6f76f23 DH |
2120 | if (old_tsec->exec_sid) { |
2121 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2122 | /* Reset exec SID on execve. */ |
a6f76f23 | 2123 | new_tsec->exec_sid = 0; |
259e5e6c AL |
2124 | |
2125 | /* | |
2126 | * Minimize confusion: if no_new_privs and a transition is | |
2127 | * explicitly requested, then fail the exec. | |
2128 | */ | |
2129 | if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) | |
2130 | return -EPERM; | |
1da177e4 LT |
2131 | } else { |
2132 | /* Check for a default transition on this program. */ | |
a6f76f23 | 2133 | rc = security_transition_sid(old_tsec->sid, isec->sid, |
652bb9b0 EP |
2134 | SECCLASS_PROCESS, NULL, |
2135 | &new_tsec->sid); | |
1da177e4 LT |
2136 | if (rc) |
2137 | return rc; | |
2138 | } | |
2139 | ||
50c205f5 | 2140 | ad.type = LSM_AUDIT_DATA_PATH; |
f48b7399 | 2141 | ad.u.path = bprm->file->f_path; |
1da177e4 | 2142 | |
259e5e6c AL |
2143 | if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) || |
2144 | (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)) | |
a6f76f23 | 2145 | new_tsec->sid = old_tsec->sid; |
1da177e4 | 2146 | |
a6f76f23 DH |
2147 | if (new_tsec->sid == old_tsec->sid) { |
2148 | rc = avc_has_perm(old_tsec->sid, isec->sid, | |
1da177e4 LT |
2149 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2150 | if (rc) | |
2151 | return rc; | |
2152 | } else { | |
2153 | /* Check permissions for the transition. */ | |
a6f76f23 | 2154 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
1da177e4 LT |
2155 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2156 | if (rc) | |
2157 | return rc; | |
2158 | ||
a6f76f23 | 2159 | rc = avc_has_perm(new_tsec->sid, isec->sid, |
1da177e4 LT |
2160 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2161 | if (rc) | |
2162 | return rc; | |
2163 | ||
a6f76f23 DH |
2164 | /* Check for shared state */ |
2165 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
2166 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, | |
2167 | SECCLASS_PROCESS, PROCESS__SHARE, | |
2168 | NULL); | |
2169 | if (rc) | |
2170 | return -EPERM; | |
2171 | } | |
2172 | ||
2173 | /* Make sure that anyone attempting to ptrace over a task that | |
2174 | * changes its SID has the appropriate permit */ | |
2175 | if (bprm->unsafe & | |
2176 | (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { | |
2177 | struct task_struct *tracer; | |
2178 | struct task_security_struct *sec; | |
2179 | u32 ptsid = 0; | |
2180 | ||
2181 | rcu_read_lock(); | |
06d98473 | 2182 | tracer = ptrace_parent(current); |
a6f76f23 DH |
2183 | if (likely(tracer != NULL)) { |
2184 | sec = __task_cred(tracer)->security; | |
2185 | ptsid = sec->sid; | |
2186 | } | |
2187 | rcu_read_unlock(); | |
2188 | ||
2189 | if (ptsid != 0) { | |
2190 | rc = avc_has_perm(ptsid, new_tsec->sid, | |
2191 | SECCLASS_PROCESS, | |
2192 | PROCESS__PTRACE, NULL); | |
2193 | if (rc) | |
2194 | return -EPERM; | |
2195 | } | |
2196 | } | |
1da177e4 | 2197 | |
a6f76f23 DH |
2198 | /* Clear any possibly unsafe personality bits on exec: */ |
2199 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
1da177e4 LT |
2200 | } |
2201 | ||
1da177e4 LT |
2202 | return 0; |
2203 | } | |
2204 | ||
828dfe1d | 2205 | static int selinux_bprm_secureexec(struct linux_binprm *bprm) |
1da177e4 | 2206 | { |
5fb49870 | 2207 | const struct task_security_struct *tsec = current_security(); |
275bb41e | 2208 | u32 sid, osid; |
1da177e4 LT |
2209 | int atsecure = 0; |
2210 | ||
275bb41e DH |
2211 | sid = tsec->sid; |
2212 | osid = tsec->osid; | |
2213 | ||
2214 | if (osid != sid) { | |
1da177e4 LT |
2215 | /* Enable secure mode for SIDs transitions unless |
2216 | the noatsecure permission is granted between | |
2217 | the two SIDs, i.e. ahp returns 0. */ | |
275bb41e | 2218 | atsecure = avc_has_perm(osid, sid, |
a6f76f23 DH |
2219 | SECCLASS_PROCESS, |
2220 | PROCESS__NOATSECURE, NULL); | |
1da177e4 LT |
2221 | } |
2222 | ||
200ac532 | 2223 | return (atsecure || cap_bprm_secureexec(bprm)); |
1da177e4 LT |
2224 | } |
2225 | ||
c3c073f8 AV |
2226 | static int match_file(const void *p, struct file *file, unsigned fd) |
2227 | { | |
2228 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2229 | } | |
2230 | ||
1da177e4 | 2231 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2232 | static inline void flush_unauthorized_files(const struct cred *cred, |
2233 | struct files_struct *files) | |
1da177e4 | 2234 | { |
1da177e4 | 2235 | struct file *file, *devnull = NULL; |
b20c8122 | 2236 | struct tty_struct *tty; |
24ec839c | 2237 | int drop_tty = 0; |
c3c073f8 | 2238 | unsigned n; |
1da177e4 | 2239 | |
24ec839c | 2240 | tty = get_current_tty(); |
1da177e4 | 2241 | if (tty) { |
ee2ffa0d | 2242 | spin_lock(&tty_files_lock); |
37dd0bd0 | 2243 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2244 | struct tty_file_private *file_priv; |
37dd0bd0 | 2245 | |
1da177e4 | 2246 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2247 | Use file_path_has_perm on the tty path directly |
2248 | rather than using file_has_perm, as this particular | |
2249 | open file may belong to another process and we are | |
2250 | only interested in the inode-based check here. */ | |
d996b62a NP |
2251 | file_priv = list_first_entry(&tty->tty_files, |
2252 | struct tty_file_private, list); | |
2253 | file = file_priv->file; | |
13f8e981 | 2254 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2255 | drop_tty = 1; |
1da177e4 | 2256 | } |
ee2ffa0d | 2257 | spin_unlock(&tty_files_lock); |
452a00d2 | 2258 | tty_kref_put(tty); |
1da177e4 | 2259 | } |
98a27ba4 EB |
2260 | /* Reset controlling tty. */ |
2261 | if (drop_tty) | |
2262 | no_tty(); | |
1da177e4 LT |
2263 | |
2264 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2265 | n = iterate_fd(files, 0, match_file, cred); |
2266 | if (!n) /* none found? */ | |
2267 | return; | |
1da177e4 | 2268 | |
c3c073f8 | 2269 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2270 | if (IS_ERR(devnull)) |
2271 | devnull = NULL; | |
2272 | /* replace all the matching ones with this */ | |
2273 | do { | |
2274 | replace_fd(n - 1, devnull, 0); | |
2275 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2276 | if (devnull) | |
c3c073f8 | 2277 | fput(devnull); |
1da177e4 LT |
2278 | } |
2279 | ||
a6f76f23 DH |
2280 | /* |
2281 | * Prepare a process for imminent new credential changes due to exec | |
2282 | */ | |
2283 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2284 | { |
a6f76f23 DH |
2285 | struct task_security_struct *new_tsec; |
2286 | struct rlimit *rlim, *initrlim; | |
2287 | int rc, i; | |
d84f4f99 | 2288 | |
a6f76f23 DH |
2289 | new_tsec = bprm->cred->security; |
2290 | if (new_tsec->sid == new_tsec->osid) | |
2291 | return; | |
1da177e4 | 2292 | |
a6f76f23 DH |
2293 | /* Close files for which the new task SID is not authorized. */ |
2294 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2295 | |
a6f76f23 DH |
2296 | /* Always clear parent death signal on SID transitions. */ |
2297 | current->pdeath_signal = 0; | |
0356357c | 2298 | |
a6f76f23 DH |
2299 | /* Check whether the new SID can inherit resource limits from the old |
2300 | * SID. If not, reset all soft limits to the lower of the current | |
2301 | * task's hard limit and the init task's soft limit. | |
2302 | * | |
2303 | * Note that the setting of hard limits (even to lower them) can be | |
2304 | * controlled by the setrlimit check. The inclusion of the init task's | |
2305 | * soft limit into the computation is to avoid resetting soft limits | |
2306 | * higher than the default soft limit for cases where the default is | |
2307 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2308 | */ | |
2309 | rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
2310 | PROCESS__RLIMITINH, NULL); | |
2311 | if (rc) { | |
eb2d55a3 ON |
2312 | /* protect against do_prlimit() */ |
2313 | task_lock(current); | |
a6f76f23 DH |
2314 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2315 | rlim = current->signal->rlim + i; | |
2316 | initrlim = init_task.signal->rlim + i; | |
2317 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2318 | } |
eb2d55a3 ON |
2319 | task_unlock(current); |
2320 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2321 | } |
2322 | } | |
2323 | ||
2324 | /* | |
a6f76f23 DH |
2325 | * Clean up the process immediately after the installation of new credentials |
2326 | * due to exec | |
1da177e4 | 2327 | */ |
a6f76f23 | 2328 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2329 | { |
a6f76f23 | 2330 | const struct task_security_struct *tsec = current_security(); |
1da177e4 | 2331 | struct itimerval itimer; |
a6f76f23 | 2332 | u32 osid, sid; |
1da177e4 LT |
2333 | int rc, i; |
2334 | ||
a6f76f23 DH |
2335 | osid = tsec->osid; |
2336 | sid = tsec->sid; | |
2337 | ||
2338 | if (sid == osid) | |
1da177e4 LT |
2339 | return; |
2340 | ||
a6f76f23 DH |
2341 | /* Check whether the new SID can inherit signal state from the old SID. |
2342 | * If not, clear itimers to avoid subsequent signal generation and | |
2343 | * flush and unblock signals. | |
2344 | * | |
2345 | * This must occur _after_ the task SID has been updated so that any | |
2346 | * kill done after the flush will be checked against the new SID. | |
2347 | */ | |
2348 | rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 LT |
2349 | if (rc) { |
2350 | memset(&itimer, 0, sizeof itimer); | |
2351 | for (i = 0; i < 3; i++) | |
2352 | do_setitimer(i, &itimer, NULL); | |
1da177e4 | 2353 | spin_lock_irq(¤t->sighand->siglock); |
3bcac026 DH |
2354 | if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) { |
2355 | __flush_signals(current); | |
2356 | flush_signal_handlers(current, 1); | |
2357 | sigemptyset(¤t->blocked); | |
2358 | } | |
1da177e4 LT |
2359 | spin_unlock_irq(¤t->sighand->siglock); |
2360 | } | |
2361 | ||
a6f76f23 DH |
2362 | /* Wake up the parent if it is waiting so that it can recheck |
2363 | * wait permission to the new task SID. */ | |
ecd6de3c | 2364 | read_lock(&tasklist_lock); |
0b7570e7 | 2365 | __wake_up_parent(current, current->real_parent); |
ecd6de3c | 2366 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2367 | } |
2368 | ||
2369 | /* superblock security operations */ | |
2370 | ||
2371 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2372 | { | |
2373 | return superblock_alloc_security(sb); | |
2374 | } | |
2375 | ||
2376 | static void selinux_sb_free_security(struct super_block *sb) | |
2377 | { | |
2378 | superblock_free_security(sb); | |
2379 | } | |
2380 | ||
2381 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2382 | { | |
2383 | if (plen > olen) | |
2384 | return 0; | |
2385 | ||
2386 | return !memcmp(prefix, option, plen); | |
2387 | } | |
2388 | ||
2389 | static inline int selinux_option(char *option, int len) | |
2390 | { | |
832cbd9a EP |
2391 | return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || |
2392 | match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || | |
2393 | match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || | |
11689d47 DQ |
2394 | match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || |
2395 | match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); | |
1da177e4 LT |
2396 | } |
2397 | ||
2398 | static inline void take_option(char **to, char *from, int *first, int len) | |
2399 | { | |
2400 | if (!*first) { | |
2401 | **to = ','; | |
2402 | *to += 1; | |
3528a953 | 2403 | } else |
1da177e4 LT |
2404 | *first = 0; |
2405 | memcpy(*to, from, len); | |
2406 | *to += len; | |
2407 | } | |
2408 | ||
828dfe1d EP |
2409 | static inline void take_selinux_option(char **to, char *from, int *first, |
2410 | int len) | |
3528a953 CO |
2411 | { |
2412 | int current_size = 0; | |
2413 | ||
2414 | if (!*first) { | |
2415 | **to = '|'; | |
2416 | *to += 1; | |
828dfe1d | 2417 | } else |
3528a953 CO |
2418 | *first = 0; |
2419 | ||
2420 | while (current_size < len) { | |
2421 | if (*from != '"') { | |
2422 | **to = *from; | |
2423 | *to += 1; | |
2424 | } | |
2425 | from += 1; | |
2426 | current_size += 1; | |
2427 | } | |
2428 | } | |
2429 | ||
e0007529 | 2430 | static int selinux_sb_copy_data(char *orig, char *copy) |
1da177e4 LT |
2431 | { |
2432 | int fnosec, fsec, rc = 0; | |
2433 | char *in_save, *in_curr, *in_end; | |
2434 | char *sec_curr, *nosec_save, *nosec; | |
3528a953 | 2435 | int open_quote = 0; |
1da177e4 LT |
2436 | |
2437 | in_curr = orig; | |
2438 | sec_curr = copy; | |
2439 | ||
1da177e4 LT |
2440 | nosec = (char *)get_zeroed_page(GFP_KERNEL); |
2441 | if (!nosec) { | |
2442 | rc = -ENOMEM; | |
2443 | goto out; | |
2444 | } | |
2445 | ||
2446 | nosec_save = nosec; | |
2447 | fnosec = fsec = 1; | |
2448 | in_save = in_end = orig; | |
2449 | ||
2450 | do { | |
3528a953 CO |
2451 | if (*in_end == '"') |
2452 | open_quote = !open_quote; | |
2453 | if ((*in_end == ',' && open_quote == 0) || | |
2454 | *in_end == '\0') { | |
1da177e4 LT |
2455 | int len = in_end - in_curr; |
2456 | ||
2457 | if (selinux_option(in_curr, len)) | |
3528a953 | 2458 | take_selinux_option(&sec_curr, in_curr, &fsec, len); |
1da177e4 LT |
2459 | else |
2460 | take_option(&nosec, in_curr, &fnosec, len); | |
2461 | ||
2462 | in_curr = in_end + 1; | |
2463 | } | |
2464 | } while (*in_end++); | |
2465 | ||
6931dfc9 | 2466 | strcpy(in_save, nosec_save); |
da3caa20 | 2467 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
2468 | out: |
2469 | return rc; | |
2470 | } | |
2471 | ||
026eb167 EP |
2472 | static int selinux_sb_remount(struct super_block *sb, void *data) |
2473 | { | |
2474 | int rc, i, *flags; | |
2475 | struct security_mnt_opts opts; | |
2476 | char *secdata, **mount_options; | |
2477 | struct superblock_security_struct *sbsec = sb->s_security; | |
2478 | ||
2479 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2480 | return 0; | |
2481 | ||
2482 | if (!data) | |
2483 | return 0; | |
2484 | ||
2485 | if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) | |
2486 | return 0; | |
2487 | ||
2488 | security_init_mnt_opts(&opts); | |
2489 | secdata = alloc_secdata(); | |
2490 | if (!secdata) | |
2491 | return -ENOMEM; | |
2492 | rc = selinux_sb_copy_data(data, secdata); | |
2493 | if (rc) | |
2494 | goto out_free_secdata; | |
2495 | ||
2496 | rc = selinux_parse_opts_str(secdata, &opts); | |
2497 | if (rc) | |
2498 | goto out_free_secdata; | |
2499 | ||
2500 | mount_options = opts.mnt_opts; | |
2501 | flags = opts.mnt_opts_flags; | |
2502 | ||
2503 | for (i = 0; i < opts.num_mnt_opts; i++) { | |
2504 | u32 sid; | |
2505 | size_t len; | |
2506 | ||
12f348b9 | 2507 | if (flags[i] == SBLABEL_MNT) |
026eb167 EP |
2508 | continue; |
2509 | len = strlen(mount_options[i]); | |
52a4c640 NA |
2510 | rc = security_context_to_sid(mount_options[i], len, &sid, |
2511 | GFP_KERNEL); | |
026eb167 EP |
2512 | if (rc) { |
2513 | printk(KERN_WARNING "SELinux: security_context_to_sid" | |
29b1deb2 LT |
2514 | "(%s) failed for (dev %s, type %s) errno=%d\n", |
2515 | mount_options[i], sb->s_id, sb->s_type->name, rc); | |
026eb167 EP |
2516 | goto out_free_opts; |
2517 | } | |
2518 | rc = -EINVAL; | |
2519 | switch (flags[i]) { | |
2520 | case FSCONTEXT_MNT: | |
2521 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) | |
2522 | goto out_bad_option; | |
2523 | break; | |
2524 | case CONTEXT_MNT: | |
2525 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2526 | goto out_bad_option; | |
2527 | break; | |
2528 | case ROOTCONTEXT_MNT: { | |
2529 | struct inode_security_struct *root_isec; | |
2530 | root_isec = sb->s_root->d_inode->i_security; | |
2531 | ||
2532 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2533 | goto out_bad_option; | |
2534 | break; | |
2535 | } | |
2536 | case DEFCONTEXT_MNT: | |
2537 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2538 | goto out_bad_option; | |
2539 | break; | |
2540 | default: | |
2541 | goto out_free_opts; | |
2542 | } | |
2543 | } | |
2544 | ||
2545 | rc = 0; | |
2546 | out_free_opts: | |
2547 | security_free_mnt_opts(&opts); | |
2548 | out_free_secdata: | |
2549 | free_secdata(secdata); | |
2550 | return rc; | |
2551 | out_bad_option: | |
2552 | printk(KERN_WARNING "SELinux: unable to change security options " | |
29b1deb2 LT |
2553 | "during remount (dev %s, type=%s)\n", sb->s_id, |
2554 | sb->s_type->name); | |
026eb167 EP |
2555 | goto out_free_opts; |
2556 | } | |
2557 | ||
12204e24 | 2558 | static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) |
1da177e4 | 2559 | { |
88e67f3b | 2560 | const struct cred *cred = current_cred(); |
2bf49690 | 2561 | struct common_audit_data ad; |
1da177e4 LT |
2562 | int rc; |
2563 | ||
2564 | rc = superblock_doinit(sb, data); | |
2565 | if (rc) | |
2566 | return rc; | |
2567 | ||
74192246 JM |
2568 | /* Allow all mounts performed by the kernel */ |
2569 | if (flags & MS_KERNMOUNT) | |
2570 | return 0; | |
2571 | ||
50c205f5 | 2572 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2573 | ad.u.dentry = sb->s_root; |
88e67f3b | 2574 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2575 | } |
2576 | ||
726c3342 | 2577 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2578 | { |
88e67f3b | 2579 | const struct cred *cred = current_cred(); |
2bf49690 | 2580 | struct common_audit_data ad; |
1da177e4 | 2581 | |
50c205f5 | 2582 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2583 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2584 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2585 | } |
2586 | ||
808d4e3c | 2587 | static int selinux_mount(const char *dev_name, |
b5266eb4 | 2588 | struct path *path, |
808d4e3c | 2589 | const char *type, |
828dfe1d EP |
2590 | unsigned long flags, |
2591 | void *data) | |
1da177e4 | 2592 | { |
88e67f3b | 2593 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2594 | |
2595 | if (flags & MS_REMOUNT) | |
d8c9584e | 2596 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2597 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2598 | else |
2875fa00 | 2599 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2600 | } |
2601 | ||
2602 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2603 | { | |
88e67f3b | 2604 | const struct cred *cred = current_cred(); |
1da177e4 | 2605 | |
88e67f3b | 2606 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2607 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2608 | } |
2609 | ||
2610 | /* inode security operations */ | |
2611 | ||
2612 | static int selinux_inode_alloc_security(struct inode *inode) | |
2613 | { | |
2614 | return inode_alloc_security(inode); | |
2615 | } | |
2616 | ||
2617 | static void selinux_inode_free_security(struct inode *inode) | |
2618 | { | |
2619 | inode_free_security(inode); | |
2620 | } | |
2621 | ||
d47be3df DQ |
2622 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
2623 | struct qstr *name, void **ctx, | |
2624 | u32 *ctxlen) | |
2625 | { | |
2626 | const struct cred *cred = current_cred(); | |
2627 | struct task_security_struct *tsec; | |
2628 | struct inode_security_struct *dsec; | |
2629 | struct superblock_security_struct *sbsec; | |
2630 | struct inode *dir = dentry->d_parent->d_inode; | |
2631 | u32 newsid; | |
2632 | int rc; | |
2633 | ||
2634 | tsec = cred->security; | |
2635 | dsec = dir->i_security; | |
2636 | sbsec = dir->i_sb->s_security; | |
2637 | ||
2638 | if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { | |
2639 | newsid = tsec->create_sid; | |
2640 | } else { | |
2641 | rc = security_transition_sid(tsec->sid, dsec->sid, | |
2642 | inode_mode_to_security_class(mode), | |
2643 | name, | |
2644 | &newsid); | |
2645 | if (rc) { | |
2646 | printk(KERN_WARNING | |
2647 | "%s: security_transition_sid failed, rc=%d\n", | |
2648 | __func__, -rc); | |
2649 | return rc; | |
2650 | } | |
2651 | } | |
2652 | ||
2653 | return security_sid_to_context(newsid, (char **)ctx, ctxlen); | |
2654 | } | |
2655 | ||
5e41ff9e | 2656 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
2657 | const struct qstr *qstr, |
2658 | const char **name, | |
2a7dba39 | 2659 | void **value, size_t *len) |
5e41ff9e | 2660 | { |
5fb49870 | 2661 | const struct task_security_struct *tsec = current_security(); |
5e41ff9e SS |
2662 | struct inode_security_struct *dsec; |
2663 | struct superblock_security_struct *sbsec; | |
275bb41e | 2664 | u32 sid, newsid, clen; |
5e41ff9e | 2665 | int rc; |
9548906b | 2666 | char *context; |
5e41ff9e | 2667 | |
5e41ff9e SS |
2668 | dsec = dir->i_security; |
2669 | sbsec = dir->i_sb->s_security; | |
5e41ff9e | 2670 | |
275bb41e DH |
2671 | sid = tsec->sid; |
2672 | newsid = tsec->create_sid; | |
2673 | ||
415103f9 EP |
2674 | if ((sbsec->flags & SE_SBINITIALIZED) && |
2675 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) | |
2676 | newsid = sbsec->mntpoint_sid; | |
12f348b9 | 2677 | else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) { |
275bb41e | 2678 | rc = security_transition_sid(sid, dsec->sid, |
5e41ff9e | 2679 | inode_mode_to_security_class(inode->i_mode), |
652bb9b0 | 2680 | qstr, &newsid); |
5e41ff9e SS |
2681 | if (rc) { |
2682 | printk(KERN_WARNING "%s: " | |
2683 | "security_transition_sid failed, rc=%d (dev=%s " | |
2684 | "ino=%ld)\n", | |
dd6f953a | 2685 | __func__, |
5e41ff9e SS |
2686 | -rc, inode->i_sb->s_id, inode->i_ino); |
2687 | return rc; | |
2688 | } | |
2689 | } | |
2690 | ||
296fddf7 | 2691 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 2692 | if (sbsec->flags & SE_SBINITIALIZED) { |
296fddf7 EP |
2693 | struct inode_security_struct *isec = inode->i_security; |
2694 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
2695 | isec->sid = newsid; | |
2696 | isec->initialized = 1; | |
2697 | } | |
5e41ff9e | 2698 | |
12f348b9 | 2699 | if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT)) |
25a74f3b SS |
2700 | return -EOPNOTSUPP; |
2701 | ||
9548906b TH |
2702 | if (name) |
2703 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 2704 | |
570bc1c2 | 2705 | if (value && len) { |
12b29f34 | 2706 | rc = security_sid_to_context_force(newsid, &context, &clen); |
9548906b | 2707 | if (rc) |
570bc1c2 | 2708 | return rc; |
570bc1c2 SS |
2709 | *value = context; |
2710 | *len = clen; | |
5e41ff9e | 2711 | } |
5e41ff9e | 2712 | |
5e41ff9e SS |
2713 | return 0; |
2714 | } | |
2715 | ||
4acdaf27 | 2716 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
2717 | { |
2718 | return may_create(dir, dentry, SECCLASS_FILE); | |
2719 | } | |
2720 | ||
1da177e4 LT |
2721 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2722 | { | |
1da177e4 LT |
2723 | return may_link(dir, old_dentry, MAY_LINK); |
2724 | } | |
2725 | ||
1da177e4 LT |
2726 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2727 | { | |
1da177e4 LT |
2728 | return may_link(dir, dentry, MAY_UNLINK); |
2729 | } | |
2730 | ||
2731 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2732 | { | |
2733 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2734 | } | |
2735 | ||
18bb1db3 | 2736 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
2737 | { |
2738 | return may_create(dir, dentry, SECCLASS_DIR); | |
2739 | } | |
2740 | ||
1da177e4 LT |
2741 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2742 | { | |
2743 | return may_link(dir, dentry, MAY_RMDIR); | |
2744 | } | |
2745 | ||
1a67aafb | 2746 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 2747 | { |
1da177e4 LT |
2748 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
2749 | } | |
2750 | ||
1da177e4 | 2751 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 2752 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
2753 | { |
2754 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2755 | } | |
2756 | ||
1da177e4 LT |
2757 | static int selinux_inode_readlink(struct dentry *dentry) |
2758 | { | |
88e67f3b DH |
2759 | const struct cred *cred = current_cred(); |
2760 | ||
2875fa00 | 2761 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
2762 | } |
2763 | ||
2764 | static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) | |
2765 | { | |
88e67f3b | 2766 | const struct cred *cred = current_cred(); |
1da177e4 | 2767 | |
2875fa00 | 2768 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
2769 | } |
2770 | ||
d4cf970d EP |
2771 | static noinline int audit_inode_permission(struct inode *inode, |
2772 | u32 perms, u32 audited, u32 denied, | |
2773 | unsigned flags) | |
1da177e4 | 2774 | { |
b782e0a6 | 2775 | struct common_audit_data ad; |
d4cf970d EP |
2776 | struct inode_security_struct *isec = inode->i_security; |
2777 | int rc; | |
2778 | ||
50c205f5 | 2779 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
2780 | ad.u.inode = inode; |
2781 | ||
2782 | rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, | |
2783 | audited, denied, &ad, flags); | |
2784 | if (rc) | |
2785 | return rc; | |
2786 | return 0; | |
2787 | } | |
2788 | ||
e74f71eb | 2789 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 2790 | { |
88e67f3b | 2791 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
2792 | u32 perms; |
2793 | bool from_access; | |
cf1dd1da | 2794 | unsigned flags = mask & MAY_NOT_BLOCK; |
2e334057 EP |
2795 | struct inode_security_struct *isec; |
2796 | u32 sid; | |
2797 | struct av_decision avd; | |
2798 | int rc, rc2; | |
2799 | u32 audited, denied; | |
1da177e4 | 2800 | |
b782e0a6 | 2801 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
2802 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
2803 | ||
b782e0a6 EP |
2804 | /* No permission to check. Existence test. */ |
2805 | if (!mask) | |
1da177e4 | 2806 | return 0; |
1da177e4 | 2807 | |
2e334057 | 2808 | validate_creds(cred); |
b782e0a6 | 2809 | |
2e334057 EP |
2810 | if (unlikely(IS_PRIVATE(inode))) |
2811 | return 0; | |
b782e0a6 EP |
2812 | |
2813 | perms = file_mask_to_av(inode->i_mode, mask); | |
2814 | ||
2e334057 EP |
2815 | sid = cred_sid(cred); |
2816 | isec = inode->i_security; | |
2817 | ||
2818 | rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd); | |
2819 | audited = avc_audit_required(perms, &avd, rc, | |
2820 | from_access ? FILE__AUDIT_ACCESS : 0, | |
2821 | &denied); | |
2822 | if (likely(!audited)) | |
2823 | return rc; | |
2824 | ||
d4cf970d | 2825 | rc2 = audit_inode_permission(inode, perms, audited, denied, flags); |
2e334057 EP |
2826 | if (rc2) |
2827 | return rc2; | |
2828 | return rc; | |
1da177e4 LT |
2829 | } |
2830 | ||
2831 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
2832 | { | |
88e67f3b | 2833 | const struct cred *cred = current_cred(); |
bc6a6008 | 2834 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 2835 | __u32 av = FILE__WRITE; |
1da177e4 | 2836 | |
bc6a6008 AW |
2837 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
2838 | if (ia_valid & ATTR_FORCE) { | |
2839 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
2840 | ATTR_FORCE); | |
2841 | if (!ia_valid) | |
2842 | return 0; | |
2843 | } | |
1da177e4 | 2844 | |
bc6a6008 AW |
2845 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
2846 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 2847 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 2848 | |
3d2195c3 | 2849 | if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE)) |
95dbf739 EP |
2850 | av |= FILE__OPEN; |
2851 | ||
2852 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
2853 | } |
2854 | ||
2855 | static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) | |
2856 | { | |
88e67f3b | 2857 | const struct cred *cred = current_cred(); |
2875fa00 EP |
2858 | struct path path; |
2859 | ||
2860 | path.dentry = dentry; | |
2861 | path.mnt = mnt; | |
88e67f3b | 2862 | |
2875fa00 | 2863 | return path_has_perm(cred, &path, FILE__GETATTR); |
1da177e4 LT |
2864 | } |
2865 | ||
8f0cfa52 | 2866 | static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) |
b5376771 | 2867 | { |
88e67f3b DH |
2868 | const struct cred *cred = current_cred(); |
2869 | ||
b5376771 SH |
2870 | if (!strncmp(name, XATTR_SECURITY_PREFIX, |
2871 | sizeof XATTR_SECURITY_PREFIX - 1)) { | |
2872 | if (!strcmp(name, XATTR_NAME_CAPS)) { | |
2873 | if (!capable(CAP_SETFCAP)) | |
2874 | return -EPERM; | |
2875 | } else if (!capable(CAP_SYS_ADMIN)) { | |
2876 | /* A different attribute in the security namespace. | |
2877 | Restrict to administrator. */ | |
2878 | return -EPERM; | |
2879 | } | |
2880 | } | |
2881 | ||
2882 | /* Not an attribute we recognize, so just check the | |
2883 | ordinary setattr permission. */ | |
2875fa00 | 2884 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
b5376771 SH |
2885 | } |
2886 | ||
8f0cfa52 DH |
2887 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
2888 | const void *value, size_t size, int flags) | |
1da177e4 | 2889 | { |
1da177e4 LT |
2890 | struct inode *inode = dentry->d_inode; |
2891 | struct inode_security_struct *isec = inode->i_security; | |
2892 | struct superblock_security_struct *sbsec; | |
2bf49690 | 2893 | struct common_audit_data ad; |
275bb41e | 2894 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
2895 | int rc = 0; |
2896 | ||
b5376771 SH |
2897 | if (strcmp(name, XATTR_NAME_SELINUX)) |
2898 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
2899 | |
2900 | sbsec = inode->i_sb->s_security; | |
12f348b9 | 2901 | if (!(sbsec->flags & SBLABEL_MNT)) |
1da177e4 LT |
2902 | return -EOPNOTSUPP; |
2903 | ||
2e149670 | 2904 | if (!inode_owner_or_capable(inode)) |
1da177e4 LT |
2905 | return -EPERM; |
2906 | ||
50c205f5 | 2907 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2908 | ad.u.dentry = dentry; |
1da177e4 | 2909 | |
275bb41e | 2910 | rc = avc_has_perm(sid, isec->sid, isec->sclass, |
1da177e4 LT |
2911 | FILE__RELABELFROM, &ad); |
2912 | if (rc) | |
2913 | return rc; | |
2914 | ||
52a4c640 | 2915 | rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); |
12b29f34 | 2916 | if (rc == -EINVAL) { |
d6ea83ec EP |
2917 | if (!capable(CAP_MAC_ADMIN)) { |
2918 | struct audit_buffer *ab; | |
2919 | size_t audit_size; | |
2920 | const char *str; | |
2921 | ||
2922 | /* We strip a nul only if it is at the end, otherwise the | |
2923 | * context contains a nul and we should audit that */ | |
e3fea3f7 AV |
2924 | if (value) { |
2925 | str = value; | |
2926 | if (str[size - 1] == '\0') | |
2927 | audit_size = size - 1; | |
2928 | else | |
2929 | audit_size = size; | |
2930 | } else { | |
2931 | str = ""; | |
2932 | audit_size = 0; | |
2933 | } | |
d6ea83ec EP |
2934 | ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); |
2935 | audit_log_format(ab, "op=setxattr invalid_context="); | |
2936 | audit_log_n_untrustedstring(ab, value, audit_size); | |
2937 | audit_log_end(ab); | |
2938 | ||
12b29f34 | 2939 | return rc; |
d6ea83ec | 2940 | } |
12b29f34 SS |
2941 | rc = security_context_to_sid_force(value, size, &newsid); |
2942 | } | |
1da177e4 LT |
2943 | if (rc) |
2944 | return rc; | |
2945 | ||
275bb41e | 2946 | rc = avc_has_perm(sid, newsid, isec->sclass, |
1da177e4 LT |
2947 | FILE__RELABELTO, &ad); |
2948 | if (rc) | |
2949 | return rc; | |
2950 | ||
275bb41e | 2951 | rc = security_validate_transition(isec->sid, newsid, sid, |
828dfe1d | 2952 | isec->sclass); |
1da177e4 LT |
2953 | if (rc) |
2954 | return rc; | |
2955 | ||
2956 | return avc_has_perm(newsid, | |
2957 | sbsec->sid, | |
2958 | SECCLASS_FILESYSTEM, | |
2959 | FILESYSTEM__ASSOCIATE, | |
2960 | &ad); | |
2961 | } | |
2962 | ||
8f0cfa52 | 2963 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 2964 | const void *value, size_t size, |
8f0cfa52 | 2965 | int flags) |
1da177e4 LT |
2966 | { |
2967 | struct inode *inode = dentry->d_inode; | |
2968 | struct inode_security_struct *isec = inode->i_security; | |
2969 | u32 newsid; | |
2970 | int rc; | |
2971 | ||
2972 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
2973 | /* Not an attribute we recognize, so nothing to do. */ | |
2974 | return; | |
2975 | } | |
2976 | ||
12b29f34 | 2977 | rc = security_context_to_sid_force(value, size, &newsid); |
1da177e4 | 2978 | if (rc) { |
12b29f34 SS |
2979 | printk(KERN_ERR "SELinux: unable to map context to SID" |
2980 | "for (%s, %lu), rc=%d\n", | |
2981 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
2982 | return; |
2983 | } | |
2984 | ||
aa9c2669 | 2985 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 2986 | isec->sid = newsid; |
aa9c2669 DQ |
2987 | isec->initialized = 1; |
2988 | ||
1da177e4 LT |
2989 | return; |
2990 | } | |
2991 | ||
8f0cfa52 | 2992 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 2993 | { |
88e67f3b DH |
2994 | const struct cred *cred = current_cred(); |
2995 | ||
2875fa00 | 2996 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
2997 | } |
2998 | ||
828dfe1d | 2999 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 3000 | { |
88e67f3b DH |
3001 | const struct cred *cred = current_cred(); |
3002 | ||
2875fa00 | 3003 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
3004 | } |
3005 | ||
8f0cfa52 | 3006 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 3007 | { |
b5376771 SH |
3008 | if (strcmp(name, XATTR_NAME_SELINUX)) |
3009 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
3010 | |
3011 | /* No one is allowed to remove a SELinux security label. | |
3012 | You can change the label, but all data must be labeled. */ | |
3013 | return -EACCES; | |
3014 | } | |
3015 | ||
d381d8a9 | 3016 | /* |
abc69bb6 | 3017 | * Copy the inode security context value to the user. |
d381d8a9 JM |
3018 | * |
3019 | * Permission check is handled by selinux_inode_getxattr hook. | |
3020 | */ | |
42492594 | 3021 | static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 3022 | { |
42492594 DQ |
3023 | u32 size; |
3024 | int error; | |
3025 | char *context = NULL; | |
1da177e4 | 3026 | struct inode_security_struct *isec = inode->i_security; |
d381d8a9 | 3027 | |
8c8570fb DK |
3028 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
3029 | return -EOPNOTSUPP; | |
d381d8a9 | 3030 | |
abc69bb6 SS |
3031 | /* |
3032 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3033 | * value even if it is not defined by current policy; otherwise, | |
3034 | * use the in-core value under current policy. | |
3035 | * Use the non-auditing forms of the permission checks since | |
3036 | * getxattr may be called by unprivileged processes commonly | |
3037 | * and lack of permission just means that we fall back to the | |
3038 | * in-core context value, not a denial. | |
3039 | */ | |
6a9de491 | 3040 | error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN, |
3699c53c | 3041 | SECURITY_CAP_NOAUDIT); |
abc69bb6 SS |
3042 | if (!error) |
3043 | error = security_sid_to_context_force(isec->sid, &context, | |
3044 | &size); | |
3045 | else | |
3046 | error = security_sid_to_context(isec->sid, &context, &size); | |
42492594 DQ |
3047 | if (error) |
3048 | return error; | |
3049 | error = size; | |
3050 | if (alloc) { | |
3051 | *buffer = context; | |
3052 | goto out_nofree; | |
3053 | } | |
3054 | kfree(context); | |
3055 | out_nofree: | |
3056 | return error; | |
1da177e4 LT |
3057 | } |
3058 | ||
3059 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 3060 | const void *value, size_t size, int flags) |
1da177e4 LT |
3061 | { |
3062 | struct inode_security_struct *isec = inode->i_security; | |
3063 | u32 newsid; | |
3064 | int rc; | |
3065 | ||
3066 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3067 | return -EOPNOTSUPP; | |
3068 | ||
3069 | if (!value || !size) | |
3070 | return -EACCES; | |
3071 | ||
52a4c640 | 3072 | rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL); |
1da177e4 LT |
3073 | if (rc) |
3074 | return rc; | |
3075 | ||
aa9c2669 | 3076 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3077 | isec->sid = newsid; |
ddd29ec6 | 3078 | isec->initialized = 1; |
1da177e4 LT |
3079 | return 0; |
3080 | } | |
3081 | ||
3082 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3083 | { | |
3084 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3085 | if (buffer && len <= buffer_size) | |
3086 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3087 | return len; | |
3088 | } | |
3089 | ||
713a04ae AD |
3090 | static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) |
3091 | { | |
3092 | struct inode_security_struct *isec = inode->i_security; | |
3093 | *secid = isec->sid; | |
3094 | } | |
3095 | ||
1da177e4 LT |
3096 | /* file security operations */ |
3097 | ||
788e7dd4 | 3098 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3099 | { |
88e67f3b | 3100 | const struct cred *cred = current_cred(); |
496ad9aa | 3101 | struct inode *inode = file_inode(file); |
1da177e4 | 3102 | |
1da177e4 LT |
3103 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3104 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3105 | mask |= MAY_APPEND; | |
3106 | ||
389fb800 PM |
3107 | return file_has_perm(cred, file, |
3108 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3109 | } |
3110 | ||
788e7dd4 YN |
3111 | static int selinux_file_permission(struct file *file, int mask) |
3112 | { | |
496ad9aa | 3113 | struct inode *inode = file_inode(file); |
20dda18b SS |
3114 | struct file_security_struct *fsec = file->f_security; |
3115 | struct inode_security_struct *isec = inode->i_security; | |
3116 | u32 sid = current_sid(); | |
3117 | ||
389fb800 | 3118 | if (!mask) |
788e7dd4 YN |
3119 | /* No permission to check. Existence test. */ |
3120 | return 0; | |
788e7dd4 | 3121 | |
20dda18b SS |
3122 | if (sid == fsec->sid && fsec->isid == isec->sid && |
3123 | fsec->pseqno == avc_policy_seqno()) | |
83d49856 | 3124 | /* No change since file_open check. */ |
20dda18b SS |
3125 | return 0; |
3126 | ||
788e7dd4 YN |
3127 | return selinux_revalidate_file_permission(file, mask); |
3128 | } | |
3129 | ||
1da177e4 LT |
3130 | static int selinux_file_alloc_security(struct file *file) |
3131 | { | |
3132 | return file_alloc_security(file); | |
3133 | } | |
3134 | ||
3135 | static void selinux_file_free_security(struct file *file) | |
3136 | { | |
3137 | file_free_security(file); | |
3138 | } | |
3139 | ||
3140 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, | |
3141 | unsigned long arg) | |
3142 | { | |
88e67f3b | 3143 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3144 | int error = 0; |
1da177e4 | 3145 | |
0b24dcb7 EP |
3146 | switch (cmd) { |
3147 | case FIONREAD: | |
3148 | /* fall through */ | |
3149 | case FIBMAP: | |
3150 | /* fall through */ | |
3151 | case FIGETBSZ: | |
3152 | /* fall through */ | |
2f99c369 | 3153 | case FS_IOC_GETFLAGS: |
0b24dcb7 | 3154 | /* fall through */ |
2f99c369 | 3155 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3156 | error = file_has_perm(cred, file, FILE__GETATTR); |
3157 | break; | |
1da177e4 | 3158 | |
2f99c369 | 3159 | case FS_IOC_SETFLAGS: |
0b24dcb7 | 3160 | /* fall through */ |
2f99c369 | 3161 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3162 | error = file_has_perm(cred, file, FILE__SETATTR); |
3163 | break; | |
3164 | ||
3165 | /* sys_ioctl() checks */ | |
3166 | case FIONBIO: | |
3167 | /* fall through */ | |
3168 | case FIOASYNC: | |
3169 | error = file_has_perm(cred, file, 0); | |
3170 | break; | |
1da177e4 | 3171 | |
0b24dcb7 EP |
3172 | case KDSKBENT: |
3173 | case KDSKBSENT: | |
6a9de491 EP |
3174 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
3175 | SECURITY_CAP_AUDIT); | |
0b24dcb7 EP |
3176 | break; |
3177 | ||
3178 | /* default case assumes that the command will go | |
3179 | * to the file's ioctl() function. | |
3180 | */ | |
3181 | default: | |
3182 | error = file_has_perm(cred, file, FILE__IOCTL); | |
3183 | } | |
3184 | return error; | |
1da177e4 LT |
3185 | } |
3186 | ||
fcaaade1 SS |
3187 | static int default_noexec; |
3188 | ||
1da177e4 LT |
3189 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3190 | { | |
88e67f3b | 3191 | const struct cred *cred = current_cred(); |
d84f4f99 | 3192 | int rc = 0; |
88e67f3b | 3193 | |
fcaaade1 SS |
3194 | if (default_noexec && |
3195 | (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3196 | /* |
3197 | * We are making executable an anonymous mapping or a | |
3198 | * private file mapping that will also be writable. | |
3199 | * This has an additional check. | |
3200 | */ | |
d84f4f99 | 3201 | rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); |
1da177e4 | 3202 | if (rc) |
d84f4f99 | 3203 | goto error; |
1da177e4 | 3204 | } |
1da177e4 LT |
3205 | |
3206 | if (file) { | |
3207 | /* read access is always possible with a mapping */ | |
3208 | u32 av = FILE__READ; | |
3209 | ||
3210 | /* write access only matters if the mapping is shared */ | |
3211 | if (shared && (prot & PROT_WRITE)) | |
3212 | av |= FILE__WRITE; | |
3213 | ||
3214 | if (prot & PROT_EXEC) | |
3215 | av |= FILE__EXECUTE; | |
3216 | ||
88e67f3b | 3217 | return file_has_perm(cred, file, av); |
1da177e4 | 3218 | } |
d84f4f99 DH |
3219 | |
3220 | error: | |
3221 | return rc; | |
1da177e4 LT |
3222 | } |
3223 | ||
e5467859 | 3224 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3225 | { |
98883bfd PM |
3226 | int rc; |
3227 | ||
3228 | /* do DAC check on address space usage */ | |
3229 | rc = cap_mmap_addr(addr); | |
3230 | if (rc) | |
3231 | return rc; | |
1da177e4 | 3232 | |
a2551df7 | 3233 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
98883bfd | 3234 | u32 sid = current_sid(); |
ed032189 EP |
3235 | rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, |
3236 | MEMPROTECT__MMAP_ZERO, NULL); | |
84336d1a EP |
3237 | } |
3238 | ||
98883bfd | 3239 | return rc; |
e5467859 | 3240 | } |
1da177e4 | 3241 | |
e5467859 AV |
3242 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3243 | unsigned long prot, unsigned long flags) | |
3244 | { | |
1da177e4 LT |
3245 | if (selinux_checkreqprot) |
3246 | prot = reqprot; | |
3247 | ||
3248 | return file_map_prot_check(file, prot, | |
3249 | (flags & MAP_TYPE) == MAP_SHARED); | |
3250 | } | |
3251 | ||
3252 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3253 | unsigned long reqprot, | |
3254 | unsigned long prot) | |
3255 | { | |
88e67f3b | 3256 | const struct cred *cred = current_cred(); |
1da177e4 LT |
3257 | |
3258 | if (selinux_checkreqprot) | |
3259 | prot = reqprot; | |
3260 | ||
fcaaade1 SS |
3261 | if (default_noexec && |
3262 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3263 | int rc = 0; |
db4c9641 SS |
3264 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3265 | vma->vm_end <= vma->vm_mm->brk) { | |
d84f4f99 | 3266 | rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); |
db4c9641 SS |
3267 | } else if (!vma->vm_file && |
3268 | vma->vm_start <= vma->vm_mm->start_stack && | |
3269 | vma->vm_end >= vma->vm_mm->start_stack) { | |
3b11a1de | 3270 | rc = current_has_perm(current, PROCESS__EXECSTACK); |
db4c9641 SS |
3271 | } else if (vma->vm_file && vma->anon_vma) { |
3272 | /* | |
3273 | * We are making executable a file mapping that has | |
3274 | * had some COW done. Since pages might have been | |
3275 | * written, check ability to execute the possibly | |
3276 | * modified content. This typically should only | |
3277 | * occur for text relocations. | |
3278 | */ | |
d84f4f99 | 3279 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3280 | } |