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Commit | Line | Data |
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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> |
effad8df | 16 | * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P. |
828dfe1d | 17 | * Paul Moore <paul.moore@hp.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 LT |
26 | #include <linux/init.h> |
27 | #include <linux/kernel.h> | |
0d094efe | 28 | #include <linux/tracehook.h> |
1da177e4 LT |
29 | #include <linux/errno.h> |
30 | #include <linux/sched.h> | |
31 | #include <linux/security.h> | |
32 | #include <linux/xattr.h> | |
33 | #include <linux/capability.h> | |
34 | #include <linux/unistd.h> | |
35 | #include <linux/mm.h> | |
36 | #include <linux/mman.h> | |
37 | #include <linux/slab.h> | |
38 | #include <linux/pagemap.h> | |
39 | #include <linux/swap.h> | |
1da177e4 LT |
40 | #include <linux/spinlock.h> |
41 | #include <linux/syscalls.h> | |
42 | #include <linux/file.h> | |
9f3acc31 | 43 | #include <linux/fdtable.h> |
1da177e4 LT |
44 | #include <linux/namei.h> |
45 | #include <linux/mount.h> | |
1da177e4 | 46 | #include <linux/proc_fs.h> |
1da177e4 LT |
47 | #include <linux/netfilter_ipv4.h> |
48 | #include <linux/netfilter_ipv6.h> | |
49 | #include <linux/tty.h> | |
50 | #include <net/icmp.h> | |
227b60f5 | 51 | #include <net/ip.h> /* for local_port_range[] */ |
1da177e4 | 52 | #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ |
220deb96 | 53 | #include <net/net_namespace.h> |
d621d35e | 54 | #include <net/netlabel.h> |
f5269710 | 55 | #include <linux/uaccess.h> |
1da177e4 | 56 | #include <asm/ioctls.h> |
d621d35e | 57 | #include <asm/atomic.h> |
1da177e4 LT |
58 | #include <linux/bitops.h> |
59 | #include <linux/interrupt.h> | |
60 | #include <linux/netdevice.h> /* for network interface checks */ | |
61 | #include <linux/netlink.h> | |
62 | #include <linux/tcp.h> | |
63 | #include <linux/udp.h> | |
2ee92d46 | 64 | #include <linux/dccp.h> |
1da177e4 LT |
65 | #include <linux/quota.h> |
66 | #include <linux/un.h> /* for Unix socket types */ | |
67 | #include <net/af_unix.h> /* for Unix socket types */ | |
68 | #include <linux/parser.h> | |
69 | #include <linux/nfs_mount.h> | |
70 | #include <net/ipv6.h> | |
71 | #include <linux/hugetlb.h> | |
72 | #include <linux/personality.h> | |
73 | #include <linux/sysctl.h> | |
74 | #include <linux/audit.h> | |
6931dfc9 | 75 | #include <linux/string.h> |
877ce7c1 | 76 | #include <linux/selinux.h> |
23970741 | 77 | #include <linux/mutex.h> |
f06febc9 | 78 | #include <linux/posix-timers.h> |
1da177e4 LT |
79 | |
80 | #include "avc.h" | |
81 | #include "objsec.h" | |
82 | #include "netif.h" | |
224dfbd8 | 83 | #include "netnode.h" |
3e112172 | 84 | #include "netport.h" |
d28d1e08 | 85 | #include "xfrm.h" |
c60475bf | 86 | #include "netlabel.h" |
9d57a7f9 | 87 | #include "audit.h" |
1da177e4 LT |
88 | |
89 | #define XATTR_SELINUX_SUFFIX "selinux" | |
90 | #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX | |
91 | ||
11689d47 | 92 | #define NUM_SEL_MNT_OPTS 5 |
c9180a57 | 93 | |
1da177e4 LT |
94 | extern unsigned int policydb_loaded_version; |
95 | extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); | |
4e5ab4cb | 96 | extern int selinux_compat_net; |
20510f2f | 97 | extern struct security_operations *security_ops; |
1da177e4 | 98 | |
d621d35e PM |
99 | /* SECMARK reference count */ |
100 | atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); | |
101 | ||
1da177e4 | 102 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
828dfe1d | 103 | int selinux_enforcing; |
1da177e4 LT |
104 | |
105 | static int __init enforcing_setup(char *str) | |
106 | { | |
f5269710 EP |
107 | unsigned long enforcing; |
108 | if (!strict_strtoul(str, 0, &enforcing)) | |
109 | selinux_enforcing = enforcing ? 1 : 0; | |
1da177e4 LT |
110 | return 1; |
111 | } | |
112 | __setup("enforcing=", enforcing_setup); | |
113 | #endif | |
114 | ||
115 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM | |
116 | int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; | |
117 | ||
118 | static int __init selinux_enabled_setup(char *str) | |
119 | { | |
f5269710 EP |
120 | unsigned long enabled; |
121 | if (!strict_strtoul(str, 0, &enabled)) | |
122 | selinux_enabled = enabled ? 1 : 0; | |
1da177e4 LT |
123 | return 1; |
124 | } | |
125 | __setup("selinux=", selinux_enabled_setup); | |
30d55280 SS |
126 | #else |
127 | int selinux_enabled = 1; | |
1da177e4 LT |
128 | #endif |
129 | ||
1da177e4 | 130 | |
6f0f0fd4 JM |
131 | /* |
132 | * Minimal support for a secondary security module, | |
133 | * just to allow the use of the capability module. | |
134 | */ | |
828dfe1d | 135 | static struct security_operations *secondary_ops; |
1da177e4 LT |
136 | |
137 | /* Lists of inode and superblock security structures initialized | |
138 | before the policy was loaded. */ | |
139 | static LIST_HEAD(superblock_security_head); | |
140 | static DEFINE_SPINLOCK(sb_security_lock); | |
141 | ||
e18b890b | 142 | static struct kmem_cache *sel_inode_cache; |
7cae7e26 | 143 | |
d621d35e PM |
144 | /** |
145 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
146 | * | |
147 | * Description: | |
148 | * This function checks the SECMARK reference counter to see if any SECMARK | |
149 | * targets are currently configured, if the reference counter is greater than | |
150 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
151 | * enabled, false (0) if SECMARK is disabled. | |
152 | * | |
153 | */ | |
154 | static int selinux_secmark_enabled(void) | |
155 | { | |
156 | return (atomic_read(&selinux_secmark_refcount) > 0); | |
157 | } | |
158 | ||
d84f4f99 DH |
159 | /* |
160 | * initialise the security for the init task | |
161 | */ | |
162 | static void cred_init_security(void) | |
1da177e4 | 163 | { |
3b11a1de | 164 | struct cred *cred = (struct cred *) current->real_cred; |
1da177e4 LT |
165 | struct task_security_struct *tsec; |
166 | ||
89d155ef | 167 | tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); |
1da177e4 | 168 | if (!tsec) |
d84f4f99 | 169 | panic("SELinux: Failed to initialize initial task.\n"); |
1da177e4 | 170 | |
d84f4f99 | 171 | tsec->osid = tsec->sid = SECINITSID_KERNEL; |
f1752eec | 172 | cred->security = tsec; |
1da177e4 LT |
173 | } |
174 | ||
88e67f3b DH |
175 | /* |
176 | * get the security ID of a set of credentials | |
177 | */ | |
178 | static inline u32 cred_sid(const struct cred *cred) | |
179 | { | |
180 | const struct task_security_struct *tsec; | |
181 | ||
182 | tsec = cred->security; | |
183 | return tsec->sid; | |
184 | } | |
185 | ||
275bb41e | 186 | /* |
3b11a1de | 187 | * get the objective security ID of a task |
275bb41e DH |
188 | */ |
189 | static inline u32 task_sid(const struct task_struct *task) | |
190 | { | |
275bb41e DH |
191 | u32 sid; |
192 | ||
193 | rcu_read_lock(); | |
88e67f3b | 194 | sid = cred_sid(__task_cred(task)); |
275bb41e DH |
195 | rcu_read_unlock(); |
196 | return sid; | |
197 | } | |
198 | ||
199 | /* | |
3b11a1de | 200 | * get the subjective security ID of the current task |
275bb41e DH |
201 | */ |
202 | static inline u32 current_sid(void) | |
203 | { | |
204 | const struct task_security_struct *tsec = current_cred()->security; | |
205 | ||
206 | return tsec->sid; | |
207 | } | |
208 | ||
88e67f3b DH |
209 | /* Allocate and free functions for each kind of security blob. */ |
210 | ||
1da177e4 LT |
211 | static int inode_alloc_security(struct inode *inode) |
212 | { | |
1da177e4 | 213 | struct inode_security_struct *isec; |
275bb41e | 214 | u32 sid = current_sid(); |
1da177e4 | 215 | |
a02fe132 | 216 | isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); |
1da177e4 LT |
217 | if (!isec) |
218 | return -ENOMEM; | |
219 | ||
23970741 | 220 | mutex_init(&isec->lock); |
1da177e4 | 221 | INIT_LIST_HEAD(&isec->list); |
1da177e4 LT |
222 | isec->inode = inode; |
223 | isec->sid = SECINITSID_UNLABELED; | |
224 | isec->sclass = SECCLASS_FILE; | |
275bb41e | 225 | isec->task_sid = sid; |
1da177e4 LT |
226 | inode->i_security = isec; |
227 | ||
228 | return 0; | |
229 | } | |
230 | ||
231 | static void inode_free_security(struct inode *inode) | |
232 | { | |
233 | struct inode_security_struct *isec = inode->i_security; | |
234 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
235 | ||
1da177e4 LT |
236 | spin_lock(&sbsec->isec_lock); |
237 | if (!list_empty(&isec->list)) | |
238 | list_del_init(&isec->list); | |
239 | spin_unlock(&sbsec->isec_lock); | |
240 | ||
241 | inode->i_security = NULL; | |
7cae7e26 | 242 | kmem_cache_free(sel_inode_cache, isec); |
1da177e4 LT |
243 | } |
244 | ||
245 | static int file_alloc_security(struct file *file) | |
246 | { | |
1da177e4 | 247 | struct file_security_struct *fsec; |
275bb41e | 248 | u32 sid = current_sid(); |
1da177e4 | 249 | |
26d2a4be | 250 | fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); |
1da177e4 LT |
251 | if (!fsec) |
252 | return -ENOMEM; | |
253 | ||
275bb41e DH |
254 | fsec->sid = sid; |
255 | fsec->fown_sid = sid; | |
1da177e4 LT |
256 | file->f_security = fsec; |
257 | ||
258 | return 0; | |
259 | } | |
260 | ||
261 | static void file_free_security(struct file *file) | |
262 | { | |
263 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 LT |
264 | file->f_security = NULL; |
265 | kfree(fsec); | |
266 | } | |
267 | ||
268 | static int superblock_alloc_security(struct super_block *sb) | |
269 | { | |
270 | struct superblock_security_struct *sbsec; | |
271 | ||
89d155ef | 272 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
273 | if (!sbsec) |
274 | return -ENOMEM; | |
275 | ||
bc7e982b | 276 | mutex_init(&sbsec->lock); |
1da177e4 LT |
277 | INIT_LIST_HEAD(&sbsec->list); |
278 | INIT_LIST_HEAD(&sbsec->isec_head); | |
279 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
280 | sbsec->sb = sb; |
281 | sbsec->sid = SECINITSID_UNLABELED; | |
282 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 283 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
284 | sb->s_security = sbsec; |
285 | ||
286 | return 0; | |
287 | } | |
288 | ||
289 | static void superblock_free_security(struct super_block *sb) | |
290 | { | |
291 | struct superblock_security_struct *sbsec = sb->s_security; | |
292 | ||
1da177e4 LT |
293 | spin_lock(&sb_security_lock); |
294 | if (!list_empty(&sbsec->list)) | |
295 | list_del_init(&sbsec->list); | |
296 | spin_unlock(&sb_security_lock); | |
297 | ||
298 | sb->s_security = NULL; | |
299 | kfree(sbsec); | |
300 | } | |
301 | ||
7d877f3b | 302 | static int sk_alloc_security(struct sock *sk, int family, gfp_t priority) |
1da177e4 LT |
303 | { |
304 | struct sk_security_struct *ssec; | |
305 | ||
89d155ef | 306 | ssec = kzalloc(sizeof(*ssec), priority); |
1da177e4 LT |
307 | if (!ssec) |
308 | return -ENOMEM; | |
309 | ||
1da177e4 | 310 | ssec->peer_sid = SECINITSID_UNLABELED; |
892c141e | 311 | ssec->sid = SECINITSID_UNLABELED; |
1da177e4 LT |
312 | sk->sk_security = ssec; |
313 | ||
f74af6e8 | 314 | selinux_netlbl_sk_security_reset(ssec, family); |
99f59ed0 | 315 | |
1da177e4 LT |
316 | return 0; |
317 | } | |
318 | ||
319 | static void sk_free_security(struct sock *sk) | |
320 | { | |
321 | struct sk_security_struct *ssec = sk->sk_security; | |
322 | ||
1da177e4 | 323 | sk->sk_security = NULL; |
6c5b3fc0 | 324 | selinux_netlbl_sk_security_free(ssec); |
1da177e4 LT |
325 | kfree(ssec); |
326 | } | |
1da177e4 LT |
327 | |
328 | /* The security server must be initialized before | |
329 | any labeling or access decisions can be provided. */ | |
330 | extern int ss_initialized; | |
331 | ||
332 | /* The file system's label must be initialized prior to use. */ | |
333 | ||
334 | static char *labeling_behaviors[6] = { | |
335 | "uses xattr", | |
336 | "uses transition SIDs", | |
337 | "uses task SIDs", | |
338 | "uses genfs_contexts", | |
339 | "not configured for labeling", | |
340 | "uses mountpoint labeling", | |
341 | }; | |
342 | ||
343 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); | |
344 | ||
345 | static inline int inode_doinit(struct inode *inode) | |
346 | { | |
347 | return inode_doinit_with_dentry(inode, NULL); | |
348 | } | |
349 | ||
350 | enum { | |
31e87930 | 351 | Opt_error = -1, |
1da177e4 LT |
352 | Opt_context = 1, |
353 | Opt_fscontext = 2, | |
c9180a57 EP |
354 | Opt_defcontext = 3, |
355 | Opt_rootcontext = 4, | |
11689d47 | 356 | Opt_labelsupport = 5, |
1da177e4 LT |
357 | }; |
358 | ||
a447c093 | 359 | static const match_table_t tokens = { |
832cbd9a EP |
360 | {Opt_context, CONTEXT_STR "%s"}, |
361 | {Opt_fscontext, FSCONTEXT_STR "%s"}, | |
362 | {Opt_defcontext, DEFCONTEXT_STR "%s"}, | |
363 | {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, | |
11689d47 | 364 | {Opt_labelsupport, LABELSUPP_STR}, |
31e87930 | 365 | {Opt_error, NULL}, |
1da177e4 LT |
366 | }; |
367 | ||
368 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
369 | ||
c312feb2 EP |
370 | static int may_context_mount_sb_relabel(u32 sid, |
371 | struct superblock_security_struct *sbsec, | |
275bb41e | 372 | const struct cred *cred) |
c312feb2 | 373 | { |
275bb41e | 374 | const struct task_security_struct *tsec = cred->security; |
c312feb2 EP |
375 | int rc; |
376 | ||
377 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
378 | FILESYSTEM__RELABELFROM, NULL); | |
379 | if (rc) | |
380 | return rc; | |
381 | ||
382 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, | |
383 | FILESYSTEM__RELABELTO, NULL); | |
384 | return rc; | |
385 | } | |
386 | ||
0808925e EP |
387 | static int may_context_mount_inode_relabel(u32 sid, |
388 | struct superblock_security_struct *sbsec, | |
275bb41e | 389 | const struct cred *cred) |
0808925e | 390 | { |
275bb41e | 391 | const struct task_security_struct *tsec = cred->security; |
0808925e EP |
392 | int rc; |
393 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
394 | FILESYSTEM__RELABELFROM, NULL); | |
395 | if (rc) | |
396 | return rc; | |
397 | ||
398 | rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
399 | FILESYSTEM__ASSOCIATE, NULL); | |
400 | return rc; | |
401 | } | |
402 | ||
c9180a57 | 403 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 404 | { |
1da177e4 | 405 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 EP |
406 | struct dentry *root = sb->s_root; |
407 | struct inode *root_inode = root->d_inode; | |
408 | int rc = 0; | |
1da177e4 | 409 | |
c9180a57 EP |
410 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
411 | /* Make sure that the xattr handler exists and that no | |
412 | error other than -ENODATA is returned by getxattr on | |
413 | the root directory. -ENODATA is ok, as this may be | |
414 | the first boot of the SELinux kernel before we have | |
415 | assigned xattr values to the filesystem. */ | |
416 | if (!root_inode->i_op->getxattr) { | |
417 | printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " | |
418 | "xattr support\n", sb->s_id, sb->s_type->name); | |
419 | rc = -EOPNOTSUPP; | |
420 | goto out; | |
421 | } | |
422 | rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); | |
423 | if (rc < 0 && rc != -ENODATA) { | |
424 | if (rc == -EOPNOTSUPP) | |
425 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
426 | "%s) has no security xattr handler\n", | |
427 | sb->s_id, sb->s_type->name); | |
428 | else | |
429 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
430 | "%s) getxattr errno %d\n", sb->s_id, | |
431 | sb->s_type->name, -rc); | |
432 | goto out; | |
433 | } | |
434 | } | |
1da177e4 | 435 | |
11689d47 | 436 | sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP); |
1da177e4 | 437 | |
c9180a57 EP |
438 | if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) |
439 | printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", | |
440 | sb->s_id, sb->s_type->name); | |
441 | else | |
442 | printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", | |
443 | sb->s_id, sb->s_type->name, | |
444 | labeling_behaviors[sbsec->behavior-1]); | |
1da177e4 | 445 | |
11689d47 DQ |
446 | if (sbsec->behavior == SECURITY_FS_USE_GENFS || |
447 | sbsec->behavior == SECURITY_FS_USE_MNTPOINT || | |
448 | sbsec->behavior == SECURITY_FS_USE_NONE || | |
449 | sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) | |
450 | sbsec->flags &= ~SE_SBLABELSUPP; | |
451 | ||
c9180a57 EP |
452 | /* Initialize the root inode. */ |
453 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 454 | |
c9180a57 EP |
455 | /* Initialize any other inodes associated with the superblock, e.g. |
456 | inodes created prior to initial policy load or inodes created | |
457 | during get_sb by a pseudo filesystem that directly | |
458 | populates itself. */ | |
459 | spin_lock(&sbsec->isec_lock); | |
460 | next_inode: | |
461 | if (!list_empty(&sbsec->isec_head)) { | |
462 | struct inode_security_struct *isec = | |
463 | list_entry(sbsec->isec_head.next, | |
464 | struct inode_security_struct, list); | |
465 | struct inode *inode = isec->inode; | |
466 | spin_unlock(&sbsec->isec_lock); | |
467 | inode = igrab(inode); | |
468 | if (inode) { | |
469 | if (!IS_PRIVATE(inode)) | |
470 | inode_doinit(inode); | |
471 | iput(inode); | |
472 | } | |
473 | spin_lock(&sbsec->isec_lock); | |
474 | list_del_init(&isec->list); | |
475 | goto next_inode; | |
476 | } | |
477 | spin_unlock(&sbsec->isec_lock); | |
478 | out: | |
479 | return rc; | |
480 | } | |
1da177e4 | 481 | |
c9180a57 EP |
482 | /* |
483 | * This function should allow an FS to ask what it's mount security | |
484 | * options were so it can use those later for submounts, displaying | |
485 | * mount options, or whatever. | |
486 | */ | |
487 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
e0007529 | 488 | struct security_mnt_opts *opts) |
c9180a57 EP |
489 | { |
490 | int rc = 0, i; | |
491 | struct superblock_security_struct *sbsec = sb->s_security; | |
492 | char *context = NULL; | |
493 | u32 len; | |
494 | char tmp; | |
1da177e4 | 495 | |
e0007529 | 496 | security_init_mnt_opts(opts); |
1da177e4 | 497 | |
0d90a7ec | 498 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
c9180a57 | 499 | return -EINVAL; |
1da177e4 | 500 | |
c9180a57 EP |
501 | if (!ss_initialized) |
502 | return -EINVAL; | |
1da177e4 | 503 | |
0d90a7ec | 504 | tmp = sbsec->flags & SE_MNTMASK; |
c9180a57 EP |
505 | /* count the number of mount options for this sb */ |
506 | for (i = 0; i < 8; i++) { | |
507 | if (tmp & 0x01) | |
e0007529 | 508 | opts->num_mnt_opts++; |
c9180a57 EP |
509 | tmp >>= 1; |
510 | } | |
11689d47 DQ |
511 | /* Check if the Label support flag is set */ |
512 | if (sbsec->flags & SE_SBLABELSUPP) | |
513 | opts->num_mnt_opts++; | |
1da177e4 | 514 | |
e0007529 EP |
515 | opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); |
516 | if (!opts->mnt_opts) { | |
c9180a57 EP |
517 | rc = -ENOMEM; |
518 | goto out_free; | |
519 | } | |
1da177e4 | 520 | |
e0007529 EP |
521 | opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); |
522 | if (!opts->mnt_opts_flags) { | |
c9180a57 EP |
523 | rc = -ENOMEM; |
524 | goto out_free; | |
525 | } | |
1da177e4 | 526 | |
c9180a57 EP |
527 | i = 0; |
528 | if (sbsec->flags & FSCONTEXT_MNT) { | |
529 | rc = security_sid_to_context(sbsec->sid, &context, &len); | |
530 | if (rc) | |
531 | goto out_free; | |
e0007529 EP |
532 | opts->mnt_opts[i] = context; |
533 | opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; | |
c9180a57 EP |
534 | } |
535 | if (sbsec->flags & CONTEXT_MNT) { | |
536 | rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); | |
537 | if (rc) | |
538 | goto out_free; | |
e0007529 EP |
539 | opts->mnt_opts[i] = context; |
540 | opts->mnt_opts_flags[i++] = CONTEXT_MNT; | |
c9180a57 EP |
541 | } |
542 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
543 | rc = security_sid_to_context(sbsec->def_sid, &context, &len); | |
544 | if (rc) | |
545 | goto out_free; | |
e0007529 EP |
546 | opts->mnt_opts[i] = context; |
547 | opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
548 | } |
549 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
550 | struct inode *root = sbsec->sb->s_root->d_inode; | |
551 | struct inode_security_struct *isec = root->i_security; | |
0808925e | 552 | |
c9180a57 EP |
553 | rc = security_sid_to_context(isec->sid, &context, &len); |
554 | if (rc) | |
555 | goto out_free; | |
e0007529 EP |
556 | opts->mnt_opts[i] = context; |
557 | opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; | |
c9180a57 | 558 | } |
11689d47 DQ |
559 | if (sbsec->flags & SE_SBLABELSUPP) { |
560 | opts->mnt_opts[i] = NULL; | |
561 | opts->mnt_opts_flags[i++] = SE_SBLABELSUPP; | |
562 | } | |
1da177e4 | 563 | |
e0007529 | 564 | BUG_ON(i != opts->num_mnt_opts); |
1da177e4 | 565 | |
c9180a57 EP |
566 | return 0; |
567 | ||
568 | out_free: | |
e0007529 | 569 | security_free_mnt_opts(opts); |
c9180a57 EP |
570 | return rc; |
571 | } | |
1da177e4 | 572 | |
c9180a57 EP |
573 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
574 | u32 old_sid, u32 new_sid) | |
575 | { | |
0d90a7ec DQ |
576 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
577 | ||
c9180a57 | 578 | /* check if the old mount command had the same options */ |
0d90a7ec | 579 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
580 | if (!(sbsec->flags & flag) || |
581 | (old_sid != new_sid)) | |
582 | return 1; | |
583 | ||
584 | /* check if we were passed the same options twice, | |
585 | * aka someone passed context=a,context=b | |
586 | */ | |
0d90a7ec DQ |
587 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
588 | if (mnt_flags & flag) | |
c9180a57 EP |
589 | return 1; |
590 | return 0; | |
591 | } | |
e0007529 | 592 | |
c9180a57 EP |
593 | /* |
594 | * Allow filesystems with binary mount data to explicitly set mount point | |
595 | * labeling information. | |
596 | */ | |
e0007529 EP |
597 | static int selinux_set_mnt_opts(struct super_block *sb, |
598 | struct security_mnt_opts *opts) | |
c9180a57 | 599 | { |
275bb41e | 600 | const struct cred *cred = current_cred(); |
c9180a57 | 601 | int rc = 0, i; |
c9180a57 EP |
602 | struct superblock_security_struct *sbsec = sb->s_security; |
603 | const char *name = sb->s_type->name; | |
089be43e JM |
604 | struct inode *inode = sbsec->sb->s_root->d_inode; |
605 | struct inode_security_struct *root_isec = inode->i_security; | |
c9180a57 EP |
606 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
607 | u32 defcontext_sid = 0; | |
e0007529 EP |
608 | char **mount_options = opts->mnt_opts; |
609 | int *flags = opts->mnt_opts_flags; | |
610 | int num_opts = opts->num_mnt_opts; | |
c9180a57 EP |
611 | |
612 | mutex_lock(&sbsec->lock); | |
613 | ||
614 | if (!ss_initialized) { | |
615 | if (!num_opts) { | |
616 | /* Defer initialization until selinux_complete_init, | |
617 | after the initial policy is loaded and the security | |
618 | server is ready to handle calls. */ | |
619 | spin_lock(&sb_security_lock); | |
620 | if (list_empty(&sbsec->list)) | |
621 | list_add(&sbsec->list, &superblock_security_head); | |
622 | spin_unlock(&sb_security_lock); | |
623 | goto out; | |
624 | } | |
625 | rc = -EINVAL; | |
744ba35e EP |
626 | printk(KERN_WARNING "SELinux: Unable to set superblock options " |
627 | "before the security server is initialized\n"); | |
1da177e4 | 628 | goto out; |
c9180a57 | 629 | } |
1da177e4 | 630 | |
e0007529 EP |
631 | /* |
632 | * Binary mount data FS will come through this function twice. Once | |
633 | * from an explicit call and once from the generic calls from the vfs. | |
634 | * Since the generic VFS calls will not contain any security mount data | |
635 | * we need to skip the double mount verification. | |
636 | * | |
637 | * This does open a hole in which we will not notice if the first | |
638 | * mount using this sb set explict options and a second mount using | |
639 | * this sb does not set any security options. (The first options | |
640 | * will be used for both mounts) | |
641 | */ | |
0d90a7ec | 642 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
e0007529 | 643 | && (num_opts == 0)) |
f5269710 | 644 | goto out; |
e0007529 | 645 | |
c9180a57 EP |
646 | /* |
647 | * parse the mount options, check if they are valid sids. | |
648 | * also check if someone is trying to mount the same sb more | |
649 | * than once with different security options. | |
650 | */ | |
651 | for (i = 0; i < num_opts; i++) { | |
652 | u32 sid; | |
11689d47 DQ |
653 | |
654 | if (flags[i] == SE_SBLABELSUPP) | |
655 | continue; | |
c9180a57 EP |
656 | rc = security_context_to_sid(mount_options[i], |
657 | strlen(mount_options[i]), &sid); | |
1da177e4 LT |
658 | if (rc) { |
659 | printk(KERN_WARNING "SELinux: security_context_to_sid" | |
660 | "(%s) failed for (dev %s, type %s) errno=%d\n", | |
c9180a57 EP |
661 | mount_options[i], sb->s_id, name, rc); |
662 | goto out; | |
663 | } | |
664 | switch (flags[i]) { | |
665 | case FSCONTEXT_MNT: | |
666 | fscontext_sid = sid; | |
667 | ||
668 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
669 | fscontext_sid)) | |
670 | goto out_double_mount; | |
671 | ||
672 | sbsec->flags |= FSCONTEXT_MNT; | |
673 | break; | |
674 | case CONTEXT_MNT: | |
675 | context_sid = sid; | |
676 | ||
677 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
678 | context_sid)) | |
679 | goto out_double_mount; | |
680 | ||
681 | sbsec->flags |= CONTEXT_MNT; | |
682 | break; | |
683 | case ROOTCONTEXT_MNT: | |
684 | rootcontext_sid = sid; | |
685 | ||
686 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
687 | rootcontext_sid)) | |
688 | goto out_double_mount; | |
689 | ||
690 | sbsec->flags |= ROOTCONTEXT_MNT; | |
691 | ||
692 | break; | |
693 | case DEFCONTEXT_MNT: | |
694 | defcontext_sid = sid; | |
695 | ||
696 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
697 | defcontext_sid)) | |
698 | goto out_double_mount; | |
699 | ||
700 | sbsec->flags |= DEFCONTEXT_MNT; | |
701 | ||
702 | break; | |
703 | default: | |
704 | rc = -EINVAL; | |
705 | goto out; | |
1da177e4 | 706 | } |
c9180a57 EP |
707 | } |
708 | ||
0d90a7ec | 709 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 710 | /* previously mounted with options, but not on this attempt? */ |
0d90a7ec | 711 | if ((sbsec->flags & SE_MNTMASK) && !num_opts) |
c9180a57 EP |
712 | goto out_double_mount; |
713 | rc = 0; | |
714 | goto out; | |
715 | } | |
716 | ||
089be43e | 717 | if (strcmp(sb->s_type->name, "proc") == 0) |
0d90a7ec | 718 | sbsec->flags |= SE_SBPROC; |
c9180a57 EP |
719 | |
720 | /* Determine the labeling behavior to use for this filesystem type. */ | |
0d90a7ec | 721 | rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid); |
c9180a57 EP |
722 | if (rc) { |
723 | printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", | |
089be43e | 724 | __func__, sb->s_type->name, rc); |
c9180a57 EP |
725 | goto out; |
726 | } | |
1da177e4 | 727 | |
c9180a57 EP |
728 | /* sets the context of the superblock for the fs being mounted. */ |
729 | if (fscontext_sid) { | |
275bb41e | 730 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
1da177e4 | 731 | if (rc) |
c9180a57 | 732 | goto out; |
1da177e4 | 733 | |
c9180a57 | 734 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
735 | } |
736 | ||
737 | /* | |
738 | * Switch to using mount point labeling behavior. | |
739 | * sets the label used on all file below the mountpoint, and will set | |
740 | * the superblock context if not already set. | |
741 | */ | |
c9180a57 EP |
742 | if (context_sid) { |
743 | if (!fscontext_sid) { | |
275bb41e DH |
744 | rc = may_context_mount_sb_relabel(context_sid, sbsec, |
745 | cred); | |
b04ea3ce | 746 | if (rc) |
c9180a57 EP |
747 | goto out; |
748 | sbsec->sid = context_sid; | |
b04ea3ce | 749 | } else { |
275bb41e DH |
750 | rc = may_context_mount_inode_relabel(context_sid, sbsec, |
751 | cred); | |
b04ea3ce | 752 | if (rc) |
c9180a57 | 753 | goto out; |
b04ea3ce | 754 | } |
c9180a57 EP |
755 | if (!rootcontext_sid) |
756 | rootcontext_sid = context_sid; | |
1da177e4 | 757 | |
c9180a57 | 758 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 759 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
760 | } |
761 | ||
c9180a57 | 762 | if (rootcontext_sid) { |
275bb41e DH |
763 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
764 | cred); | |
0808925e | 765 | if (rc) |
c9180a57 | 766 | goto out; |
0808925e | 767 | |
c9180a57 EP |
768 | root_isec->sid = rootcontext_sid; |
769 | root_isec->initialized = 1; | |
0808925e EP |
770 | } |
771 | ||
c9180a57 EP |
772 | if (defcontext_sid) { |
773 | if (sbsec->behavior != SECURITY_FS_USE_XATTR) { | |
774 | rc = -EINVAL; | |
775 | printk(KERN_WARNING "SELinux: defcontext option is " | |
776 | "invalid for this filesystem type\n"); | |
777 | goto out; | |
1da177e4 LT |
778 | } |
779 | ||
c9180a57 EP |
780 | if (defcontext_sid != sbsec->def_sid) { |
781 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
275bb41e | 782 | sbsec, cred); |
c9180a57 EP |
783 | if (rc) |
784 | goto out; | |
785 | } | |
1da177e4 | 786 | |
c9180a57 | 787 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
788 | } |
789 | ||
c9180a57 | 790 | rc = sb_finish_set_opts(sb); |
1da177e4 | 791 | out: |
c9180a57 | 792 | mutex_unlock(&sbsec->lock); |
1da177e4 | 793 | return rc; |
c9180a57 EP |
794 | out_double_mount: |
795 | rc = -EINVAL; | |
796 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " | |
797 | "security settings for (dev %s, type %s)\n", sb->s_id, name); | |
798 | goto out; | |
1da177e4 LT |
799 | } |
800 | ||
c9180a57 EP |
801 | static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, |
802 | struct super_block *newsb) | |
1da177e4 | 803 | { |
c9180a57 EP |
804 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
805 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 806 | |
c9180a57 EP |
807 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
808 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
809 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 810 | |
0f5e6420 EP |
811 | /* |
812 | * if the parent was able to be mounted it clearly had no special lsm | |
813 | * mount options. thus we can safely put this sb on the list and deal | |
814 | * with it later | |
815 | */ | |
816 | if (!ss_initialized) { | |
817 | spin_lock(&sb_security_lock); | |
818 | if (list_empty(&newsbsec->list)) | |
819 | list_add(&newsbsec->list, &superblock_security_head); | |
820 | spin_unlock(&sb_security_lock); | |
821 | return; | |
822 | } | |
c9180a57 | 823 | |
c9180a57 | 824 | /* how can we clone if the old one wasn't set up?? */ |
0d90a7ec | 825 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
c9180a57 | 826 | |
5a552617 | 827 | /* if fs is reusing a sb, just let its options stand... */ |
0d90a7ec | 828 | if (newsbsec->flags & SE_SBINITIALIZED) |
5a552617 EP |
829 | return; |
830 | ||
c9180a57 EP |
831 | mutex_lock(&newsbsec->lock); |
832 | ||
833 | newsbsec->flags = oldsbsec->flags; | |
834 | ||
835 | newsbsec->sid = oldsbsec->sid; | |
836 | newsbsec->def_sid = oldsbsec->def_sid; | |
837 | newsbsec->behavior = oldsbsec->behavior; | |
838 | ||
839 | if (set_context) { | |
840 | u32 sid = oldsbsec->mntpoint_sid; | |
841 | ||
842 | if (!set_fscontext) | |
843 | newsbsec->sid = sid; | |
844 | if (!set_rootcontext) { | |
845 | struct inode *newinode = newsb->s_root->d_inode; | |
846 | struct inode_security_struct *newisec = newinode->i_security; | |
847 | newisec->sid = sid; | |
848 | } | |
849 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 850 | } |
c9180a57 EP |
851 | if (set_rootcontext) { |
852 | const struct inode *oldinode = oldsb->s_root->d_inode; | |
853 | const struct inode_security_struct *oldisec = oldinode->i_security; | |
854 | struct inode *newinode = newsb->s_root->d_inode; | |
855 | struct inode_security_struct *newisec = newinode->i_security; | |
1da177e4 | 856 | |
c9180a57 | 857 | newisec->sid = oldisec->sid; |
1da177e4 LT |
858 | } |
859 | ||
c9180a57 EP |
860 | sb_finish_set_opts(newsb); |
861 | mutex_unlock(&newsbsec->lock); | |
862 | } | |
863 | ||
2e1479d9 AB |
864 | static int selinux_parse_opts_str(char *options, |
865 | struct security_mnt_opts *opts) | |
c9180a57 | 866 | { |
e0007529 | 867 | char *p; |
c9180a57 EP |
868 | char *context = NULL, *defcontext = NULL; |
869 | char *fscontext = NULL, *rootcontext = NULL; | |
e0007529 | 870 | int rc, num_mnt_opts = 0; |
1da177e4 | 871 | |
e0007529 | 872 | opts->num_mnt_opts = 0; |
1da177e4 | 873 | |
c9180a57 EP |
874 | /* Standard string-based options. */ |
875 | while ((p = strsep(&options, "|")) != NULL) { | |
876 | int token; | |
877 | substring_t args[MAX_OPT_ARGS]; | |
1da177e4 | 878 | |
c9180a57 EP |
879 | if (!*p) |
880 | continue; | |
1da177e4 | 881 | |
c9180a57 | 882 | token = match_token(p, tokens, args); |
1da177e4 | 883 | |
c9180a57 EP |
884 | switch (token) { |
885 | case Opt_context: | |
886 | if (context || defcontext) { | |
887 | rc = -EINVAL; | |
888 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
889 | goto out_err; | |
890 | } | |
891 | context = match_strdup(&args[0]); | |
892 | if (!context) { | |
893 | rc = -ENOMEM; | |
894 | goto out_err; | |
895 | } | |
896 | break; | |
897 | ||
898 | case Opt_fscontext: | |
899 | if (fscontext) { | |
900 | rc = -EINVAL; | |
901 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
902 | goto out_err; | |
903 | } | |
904 | fscontext = match_strdup(&args[0]); | |
905 | if (!fscontext) { | |
906 | rc = -ENOMEM; | |
907 | goto out_err; | |
908 | } | |
909 | break; | |
910 | ||
911 | case Opt_rootcontext: | |
912 | if (rootcontext) { | |
913 | rc = -EINVAL; | |
914 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
915 | goto out_err; | |
916 | } | |
917 | rootcontext = match_strdup(&args[0]); | |
918 | if (!rootcontext) { | |
919 | rc = -ENOMEM; | |
920 | goto out_err; | |
921 | } | |
922 | break; | |
923 | ||
924 | case Opt_defcontext: | |
925 | if (context || defcontext) { | |
926 | rc = -EINVAL; | |
927 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
928 | goto out_err; | |
929 | } | |
930 | defcontext = match_strdup(&args[0]); | |
931 | if (!defcontext) { | |
932 | rc = -ENOMEM; | |
933 | goto out_err; | |
934 | } | |
935 | break; | |
11689d47 DQ |
936 | case Opt_labelsupport: |
937 | break; | |
c9180a57 EP |
938 | default: |
939 | rc = -EINVAL; | |
940 | printk(KERN_WARNING "SELinux: unknown mount option\n"); | |
941 | goto out_err; | |
1da177e4 | 942 | |
1da177e4 | 943 | } |
1da177e4 | 944 | } |
c9180a57 | 945 | |
e0007529 EP |
946 | rc = -ENOMEM; |
947 | opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); | |
948 | if (!opts->mnt_opts) | |
949 | goto out_err; | |
950 | ||
951 | opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); | |
952 | if (!opts->mnt_opts_flags) { | |
953 | kfree(opts->mnt_opts); | |
954 | goto out_err; | |
955 | } | |
956 | ||
c9180a57 | 957 | if (fscontext) { |
e0007529 EP |
958 | opts->mnt_opts[num_mnt_opts] = fscontext; |
959 | opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; | |
c9180a57 EP |
960 | } |
961 | if (context) { | |
e0007529 EP |
962 | opts->mnt_opts[num_mnt_opts] = context; |
963 | opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; | |
c9180a57 EP |
964 | } |
965 | if (rootcontext) { | |
e0007529 EP |
966 | opts->mnt_opts[num_mnt_opts] = rootcontext; |
967 | opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; | |
c9180a57 EP |
968 | } |
969 | if (defcontext) { | |
e0007529 EP |
970 | opts->mnt_opts[num_mnt_opts] = defcontext; |
971 | opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
972 | } |
973 | ||
e0007529 EP |
974 | opts->num_mnt_opts = num_mnt_opts; |
975 | return 0; | |
976 | ||
c9180a57 EP |
977 | out_err: |
978 | kfree(context); | |
979 | kfree(defcontext); | |
980 | kfree(fscontext); | |
981 | kfree(rootcontext); | |
1da177e4 LT |
982 | return rc; |
983 | } | |
e0007529 EP |
984 | /* |
985 | * string mount options parsing and call set the sbsec | |
986 | */ | |
987 | static int superblock_doinit(struct super_block *sb, void *data) | |
988 | { | |
989 | int rc = 0; | |
990 | char *options = data; | |
991 | struct security_mnt_opts opts; | |
992 | ||
993 | security_init_mnt_opts(&opts); | |
994 | ||
995 | if (!data) | |
996 | goto out; | |
997 | ||
998 | BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); | |
999 | ||
1000 | rc = selinux_parse_opts_str(options, &opts); | |
1001 | if (rc) | |
1002 | goto out_err; | |
1003 | ||
1004 | out: | |
1005 | rc = selinux_set_mnt_opts(sb, &opts); | |
1006 | ||
1007 | out_err: | |
1008 | security_free_mnt_opts(&opts); | |
1009 | return rc; | |
1010 | } | |
1da177e4 | 1011 | |
3583a711 AB |
1012 | static void selinux_write_opts(struct seq_file *m, |
1013 | struct security_mnt_opts *opts) | |
2069f457 EP |
1014 | { |
1015 | int i; | |
1016 | char *prefix; | |
1017 | ||
1018 | for (i = 0; i < opts->num_mnt_opts; i++) { | |
11689d47 DQ |
1019 | char *has_comma; |
1020 | ||
1021 | if (opts->mnt_opts[i]) | |
1022 | has_comma = strchr(opts->mnt_opts[i], ','); | |
1023 | else | |
1024 | has_comma = NULL; | |
2069f457 EP |
1025 | |
1026 | switch (opts->mnt_opts_flags[i]) { | |
1027 | case CONTEXT_MNT: | |
1028 | prefix = CONTEXT_STR; | |
1029 | break; | |
1030 | case FSCONTEXT_MNT: | |
1031 | prefix = FSCONTEXT_STR; | |
1032 | break; | |
1033 | case ROOTCONTEXT_MNT: | |
1034 | prefix = ROOTCONTEXT_STR; | |
1035 | break; | |
1036 | case DEFCONTEXT_MNT: | |
1037 | prefix = DEFCONTEXT_STR; | |
1038 | break; | |
11689d47 DQ |
1039 | case SE_SBLABELSUPP: |
1040 | seq_putc(m, ','); | |
1041 | seq_puts(m, LABELSUPP_STR); | |
1042 | continue; | |
2069f457 EP |
1043 | default: |
1044 | BUG(); | |
1045 | }; | |
1046 | /* we need a comma before each option */ | |
1047 | seq_putc(m, ','); | |
1048 | seq_puts(m, prefix); | |
1049 | if (has_comma) | |
1050 | seq_putc(m, '\"'); | |
1051 | seq_puts(m, opts->mnt_opts[i]); | |
1052 | if (has_comma) | |
1053 | seq_putc(m, '\"'); | |
1054 | } | |
1055 | } | |
1056 | ||
1057 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1058 | { | |
1059 | struct security_mnt_opts opts; | |
1060 | int rc; | |
1061 | ||
1062 | rc = selinux_get_mnt_opts(sb, &opts); | |
383795c2 EP |
1063 | if (rc) { |
1064 | /* before policy load we may get EINVAL, don't show anything */ | |
1065 | if (rc == -EINVAL) | |
1066 | rc = 0; | |
2069f457 | 1067 | return rc; |
383795c2 | 1068 | } |
2069f457 EP |
1069 | |
1070 | selinux_write_opts(m, &opts); | |
1071 | ||
1072 | security_free_mnt_opts(&opts); | |
1073 | ||
1074 | return rc; | |
1075 | } | |
1076 | ||
1da177e4 LT |
1077 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1078 | { | |
1079 | switch (mode & S_IFMT) { | |
1080 | case S_IFSOCK: | |
1081 | return SECCLASS_SOCK_FILE; | |
1082 | case S_IFLNK: | |
1083 | return SECCLASS_LNK_FILE; | |
1084 | case S_IFREG: | |
1085 | return SECCLASS_FILE; | |
1086 | case S_IFBLK: | |
1087 | return SECCLASS_BLK_FILE; | |
1088 | case S_IFDIR: | |
1089 | return SECCLASS_DIR; | |
1090 | case S_IFCHR: | |
1091 | return SECCLASS_CHR_FILE; | |
1092 | case S_IFIFO: | |
1093 | return SECCLASS_FIFO_FILE; | |
1094 | ||
1095 | } | |
1096 | ||
1097 | return SECCLASS_FILE; | |
1098 | } | |
1099 | ||
13402580 JM |
1100 | static inline int default_protocol_stream(int protocol) |
1101 | { | |
1102 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1103 | } | |
1104 | ||
1105 | static inline int default_protocol_dgram(int protocol) | |
1106 | { | |
1107 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1108 | } | |
1109 | ||
1da177e4 LT |
1110 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1111 | { | |
1112 | switch (family) { | |
1113 | case PF_UNIX: | |
1114 | switch (type) { | |
1115 | case SOCK_STREAM: | |
1116 | case SOCK_SEQPACKET: | |
1117 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1118 | case SOCK_DGRAM: | |
1119 | return SECCLASS_UNIX_DGRAM_SOCKET; | |
1120 | } | |
1121 | break; | |
1122 | case PF_INET: | |
1123 | case PF_INET6: | |
1124 | switch (type) { | |
1125 | case SOCK_STREAM: | |
13402580 JM |
1126 | if (default_protocol_stream(protocol)) |
1127 | return SECCLASS_TCP_SOCKET; | |
1128 | else | |
1129 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1130 | case SOCK_DGRAM: |
13402580 JM |
1131 | if (default_protocol_dgram(protocol)) |
1132 | return SECCLASS_UDP_SOCKET; | |
1133 | else | |
1134 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1135 | case SOCK_DCCP: |
1136 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1137 | default: |
1da177e4 LT |
1138 | return SECCLASS_RAWIP_SOCKET; |
1139 | } | |
1140 | break; | |
1141 | case PF_NETLINK: | |
1142 | switch (protocol) { | |
1143 | case NETLINK_ROUTE: | |
1144 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
1145 | case NETLINK_FIREWALL: | |
1146 | return SECCLASS_NETLINK_FIREWALL_SOCKET; | |
216efaaa | 1147 | case NETLINK_INET_DIAG: |
1da177e4 LT |
1148 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1149 | case NETLINK_NFLOG: | |
1150 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1151 | case NETLINK_XFRM: | |
1152 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1153 | case NETLINK_SELINUX: | |
1154 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
1155 | case NETLINK_AUDIT: | |
1156 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
1157 | case NETLINK_IP6_FW: | |
1158 | return SECCLASS_NETLINK_IP6FW_SOCKET; | |
1159 | case NETLINK_DNRTMSG: | |
1160 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1161 | case NETLINK_KOBJECT_UEVENT: |
1162 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
1da177e4 LT |
1163 | default: |
1164 | return SECCLASS_NETLINK_SOCKET; | |
1165 | } | |
1166 | case PF_PACKET: | |
1167 | return SECCLASS_PACKET_SOCKET; | |
1168 | case PF_KEY: | |
1169 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1170 | case PF_APPLETALK: |
1171 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1172 | } |
1173 | ||
1174 | return SECCLASS_SOCKET; | |
1175 | } | |
1176 | ||
1177 | #ifdef CONFIG_PROC_FS | |
1178 | static int selinux_proc_get_sid(struct proc_dir_entry *de, | |
1179 | u16 tclass, | |
1180 | u32 *sid) | |
1181 | { | |
1182 | int buflen, rc; | |
1183 | char *buffer, *path, *end; | |
1184 | ||
828dfe1d | 1185 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1186 | if (!buffer) |
1187 | return -ENOMEM; | |
1188 | ||
1189 | buflen = PAGE_SIZE; | |
1190 | end = buffer+buflen; | |
1191 | *--end = '\0'; | |
1192 | buflen--; | |
1193 | path = end-1; | |
1194 | *path = '/'; | |
1195 | while (de && de != de->parent) { | |
1196 | buflen -= de->namelen + 1; | |
1197 | if (buflen < 0) | |
1198 | break; | |
1199 | end -= de->namelen; | |
1200 | memcpy(end, de->name, de->namelen); | |
1201 | *--end = '/'; | |
1202 | path = end; | |
1203 | de = de->parent; | |
1204 | } | |
1205 | rc = security_genfs_sid("proc", path, tclass, sid); | |
1206 | free_page((unsigned long)buffer); | |
1207 | return rc; | |
1208 | } | |
1209 | #else | |
1210 | static int selinux_proc_get_sid(struct proc_dir_entry *de, | |
1211 | u16 tclass, | |
1212 | u32 *sid) | |
1213 | { | |
1214 | return -EINVAL; | |
1215 | } | |
1216 | #endif | |
1217 | ||
1218 | /* The inode's security attributes must be initialized before first use. */ | |
1219 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1220 | { | |
1221 | struct superblock_security_struct *sbsec = NULL; | |
1222 | struct inode_security_struct *isec = inode->i_security; | |
1223 | u32 sid; | |
1224 | struct dentry *dentry; | |
1225 | #define INITCONTEXTLEN 255 | |
1226 | char *context = NULL; | |
1227 | unsigned len = 0; | |
1228 | int rc = 0; | |
1da177e4 LT |
1229 | |
1230 | if (isec->initialized) | |
1231 | goto out; | |
1232 | ||
23970741 | 1233 | mutex_lock(&isec->lock); |
1da177e4 | 1234 | if (isec->initialized) |
23970741 | 1235 | goto out_unlock; |
1da177e4 LT |
1236 | |
1237 | sbsec = inode->i_sb->s_security; | |
0d90a7ec | 1238 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1239 | /* Defer initialization until selinux_complete_init, |
1240 | after the initial policy is loaded and the security | |
1241 | server is ready to handle calls. */ | |
1242 | spin_lock(&sbsec->isec_lock); | |
1243 | if (list_empty(&isec->list)) | |
1244 | list_add(&isec->list, &sbsec->isec_head); | |
1245 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1246 | goto out_unlock; |
1da177e4 LT |
1247 | } |
1248 | ||
1249 | switch (sbsec->behavior) { | |
1250 | case SECURITY_FS_USE_XATTR: | |
1251 | if (!inode->i_op->getxattr) { | |
1252 | isec->sid = sbsec->def_sid; | |
1253 | break; | |
1254 | } | |
1255 | ||
1256 | /* Need a dentry, since the xattr API requires one. | |
1257 | Life would be simpler if we could just pass the inode. */ | |
1258 | if (opt_dentry) { | |
1259 | /* Called from d_instantiate or d_splice_alias. */ | |
1260 | dentry = dget(opt_dentry); | |
1261 | } else { | |
1262 | /* Called from selinux_complete_init, try to find a dentry. */ | |
1263 | dentry = d_find_alias(inode); | |
1264 | } | |
1265 | if (!dentry) { | |
744ba35e | 1266 | printk(KERN_WARNING "SELinux: %s: no dentry for dev=%s " |
dd6f953a | 1267 | "ino=%ld\n", __func__, inode->i_sb->s_id, |
1da177e4 | 1268 | inode->i_ino); |
23970741 | 1269 | goto out_unlock; |
1da177e4 LT |
1270 | } |
1271 | ||
1272 | len = INITCONTEXTLEN; | |
869ab514 | 1273 | context = kmalloc(len, GFP_NOFS); |
1da177e4 LT |
1274 | if (!context) { |
1275 | rc = -ENOMEM; | |
1276 | dput(dentry); | |
23970741 | 1277 | goto out_unlock; |
1da177e4 LT |
1278 | } |
1279 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, | |
1280 | context, len); | |
1281 | if (rc == -ERANGE) { | |
1282 | /* Need a larger buffer. Query for the right size. */ | |
1283 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, | |
1284 | NULL, 0); | |
1285 | if (rc < 0) { | |
1286 | dput(dentry); | |
23970741 | 1287 | goto out_unlock; |
1da177e4 LT |
1288 | } |
1289 | kfree(context); | |
1290 | len = rc; | |
869ab514 | 1291 | context = kmalloc(len, GFP_NOFS); |
1da177e4 LT |
1292 | if (!context) { |
1293 | rc = -ENOMEM; | |
1294 | dput(dentry); | |
23970741 | 1295 | goto out_unlock; |
1da177e4 LT |
1296 | } |
1297 | rc = inode->i_op->getxattr(dentry, | |
1298 | XATTR_NAME_SELINUX, | |
1299 | context, len); | |
1300 | } | |
1301 | dput(dentry); | |
1302 | if (rc < 0) { | |
1303 | if (rc != -ENODATA) { | |
744ba35e | 1304 | printk(KERN_WARNING "SELinux: %s: getxattr returned " |
dd6f953a | 1305 | "%d for dev=%s ino=%ld\n", __func__, |
1da177e4 LT |
1306 | -rc, inode->i_sb->s_id, inode->i_ino); |
1307 | kfree(context); | |
23970741 | 1308 | goto out_unlock; |
1da177e4 LT |
1309 | } |
1310 | /* Map ENODATA to the default file SID */ | |
1311 | sid = sbsec->def_sid; | |
1312 | rc = 0; | |
1313 | } else { | |
f5c1d5b2 | 1314 | rc = security_context_to_sid_default(context, rc, &sid, |
869ab514 SS |
1315 | sbsec->def_sid, |
1316 | GFP_NOFS); | |
1da177e4 | 1317 | if (rc) { |
4ba0a8ad EP |
1318 | char *dev = inode->i_sb->s_id; |
1319 | unsigned long ino = inode->i_ino; | |
1320 | ||
1321 | if (rc == -EINVAL) { | |
1322 | if (printk_ratelimit()) | |
1323 | printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " | |
1324 | "context=%s. This indicates you may need to relabel the inode or the " | |
1325 | "filesystem in question.\n", ino, dev, context); | |
1326 | } else { | |
1327 | printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " | |
1328 | "returned %d for dev=%s ino=%ld\n", | |
1329 | __func__, context, -rc, dev, ino); | |
1330 | } | |
1da177e4 LT |
1331 | kfree(context); |
1332 | /* Leave with the unlabeled SID */ | |
1333 | rc = 0; | |
1334 | break; | |
1335 | } | |
1336 | } | |
1337 | kfree(context); | |
1338 | isec->sid = sid; | |
1339 | break; | |
1340 | case SECURITY_FS_USE_TASK: | |
1341 | isec->sid = isec->task_sid; | |
1342 | break; | |
1343 | case SECURITY_FS_USE_TRANS: | |
1344 | /* Default to the fs SID. */ | |
1345 | isec->sid = sbsec->sid; | |
1346 | ||
1347 | /* Try to obtain a transition SID. */ | |
1348 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1349 | rc = security_transition_sid(isec->task_sid, | |
1350 | sbsec->sid, | |
1351 | isec->sclass, | |
1352 | &sid); | |
1353 | if (rc) | |
23970741 | 1354 | goto out_unlock; |
1da177e4 LT |
1355 | isec->sid = sid; |
1356 | break; | |
c312feb2 EP |
1357 | case SECURITY_FS_USE_MNTPOINT: |
1358 | isec->sid = sbsec->mntpoint_sid; | |
1359 | break; | |
1da177e4 | 1360 | default: |
c312feb2 | 1361 | /* Default to the fs superblock SID. */ |
1da177e4 LT |
1362 | isec->sid = sbsec->sid; |
1363 | ||
0d90a7ec | 1364 | if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { |
1da177e4 LT |
1365 | struct proc_inode *proci = PROC_I(inode); |
1366 | if (proci->pde) { | |
1367 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1368 | rc = selinux_proc_get_sid(proci->pde, | |
1369 | isec->sclass, | |
1370 | &sid); | |
1371 | if (rc) | |
23970741 | 1372 | goto out_unlock; |
1da177e4 LT |
1373 | isec->sid = sid; |
1374 | } | |
1375 | } | |
1376 | break; | |
1377 | } | |
1378 | ||
1379 | isec->initialized = 1; | |
1380 | ||
23970741 EP |
1381 | out_unlock: |
1382 | mutex_unlock(&isec->lock); | |
1da177e4 LT |
1383 | out: |
1384 | if (isec->sclass == SECCLASS_FILE) | |
1385 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1da177e4 LT |
1386 | return rc; |
1387 | } | |
1388 | ||
1389 | /* Convert a Linux signal to an access vector. */ | |
1390 | static inline u32 signal_to_av(int sig) | |
1391 | { | |
1392 | u32 perm = 0; | |
1393 | ||
1394 | switch (sig) { | |
1395 | case SIGCHLD: | |
1396 | /* Commonly granted from child to parent. */ | |
1397 | perm = PROCESS__SIGCHLD; | |
1398 | break; | |
1399 | case SIGKILL: | |
1400 | /* Cannot be caught or ignored */ | |
1401 | perm = PROCESS__SIGKILL; | |
1402 | break; | |
1403 | case SIGSTOP: | |
1404 | /* Cannot be caught or ignored */ | |
1405 | perm = PROCESS__SIGSTOP; | |
1406 | break; | |
1407 | default: | |
1408 | /* All other signals. */ | |
1409 | perm = PROCESS__SIGNAL; | |
1410 | break; | |
1411 | } | |
1412 | ||
1413 | return perm; | |
1414 | } | |
1415 | ||
d84f4f99 DH |
1416 | /* |
1417 | * Check permission between a pair of credentials | |
1418 | * fork check, ptrace check, etc. | |
1419 | */ | |
1420 | static int cred_has_perm(const struct cred *actor, | |
1421 | const struct cred *target, | |
1422 | u32 perms) | |
1423 | { | |
1424 | u32 asid = cred_sid(actor), tsid = cred_sid(target); | |
1425 | ||
1426 | return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); | |
1427 | } | |
1428 | ||
275bb41e | 1429 | /* |
88e67f3b | 1430 | * Check permission between a pair of tasks, e.g. signal checks, |
275bb41e DH |
1431 | * fork check, ptrace check, etc. |
1432 | * tsk1 is the actor and tsk2 is the target | |
3b11a1de | 1433 | * - this uses the default subjective creds of tsk1 |
275bb41e DH |
1434 | */ |
1435 | static int task_has_perm(const struct task_struct *tsk1, | |
1436 | const struct task_struct *tsk2, | |
1da177e4 LT |
1437 | u32 perms) |
1438 | { | |
275bb41e DH |
1439 | const struct task_security_struct *__tsec1, *__tsec2; |
1440 | u32 sid1, sid2; | |
1da177e4 | 1441 | |
275bb41e DH |
1442 | rcu_read_lock(); |
1443 | __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; | |
1444 | __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; | |
1445 | rcu_read_unlock(); | |
1446 | return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); | |
1da177e4 LT |
1447 | } |
1448 | ||
3b11a1de DH |
1449 | /* |
1450 | * Check permission between current and another task, e.g. signal checks, | |
1451 | * fork check, ptrace check, etc. | |
1452 | * current is the actor and tsk2 is the target | |
1453 | * - this uses current's subjective creds | |
1454 | */ | |
1455 | static int current_has_perm(const struct task_struct *tsk, | |
1456 | u32 perms) | |
1457 | { | |
1458 | u32 sid, tsid; | |
1459 | ||
1460 | sid = current_sid(); | |
1461 | tsid = task_sid(tsk); | |
1462 | return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); | |
1463 | } | |
1464 | ||
b68e418c SS |
1465 | #if CAP_LAST_CAP > 63 |
1466 | #error Fix SELinux to handle capabilities > 63. | |
1467 | #endif | |
1468 | ||
1da177e4 LT |
1469 | /* Check whether a task is allowed to use a capability. */ |
1470 | static int task_has_capability(struct task_struct *tsk, | |
3699c53c | 1471 | const struct cred *cred, |
06112163 | 1472 | int cap, int audit) |
1da177e4 | 1473 | { |
1da177e4 | 1474 | struct avc_audit_data ad; |
06112163 | 1475 | struct av_decision avd; |
b68e418c | 1476 | u16 sclass; |
3699c53c | 1477 | u32 sid = cred_sid(cred); |
b68e418c | 1478 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1479 | int rc; |
1da177e4 | 1480 | |
828dfe1d | 1481 | AVC_AUDIT_DATA_INIT(&ad, CAP); |
1da177e4 LT |
1482 | ad.tsk = tsk; |
1483 | ad.u.cap = cap; | |
1484 | ||
b68e418c SS |
1485 | switch (CAP_TO_INDEX(cap)) { |
1486 | case 0: | |
1487 | sclass = SECCLASS_CAPABILITY; | |
1488 | break; | |
1489 | case 1: | |
1490 | sclass = SECCLASS_CAPABILITY2; | |
1491 | break; | |
1492 | default: | |
1493 | printk(KERN_ERR | |
1494 | "SELinux: out of range capability %d\n", cap); | |
1495 | BUG(); | |
1496 | } | |
06112163 | 1497 | |
275bb41e | 1498 | rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); |
06112163 | 1499 | if (audit == SECURITY_CAP_AUDIT) |
275bb41e | 1500 | avc_audit(sid, sid, sclass, av, &avd, rc, &ad); |
06112163 | 1501 | return rc; |
1da177e4 LT |
1502 | } |
1503 | ||
1504 | /* Check whether a task is allowed to use a system operation. */ | |
1505 | static int task_has_system(struct task_struct *tsk, | |
1506 | u32 perms) | |
1507 | { | |
275bb41e | 1508 | u32 sid = task_sid(tsk); |
1da177e4 | 1509 | |
275bb41e | 1510 | return avc_has_perm(sid, SECINITSID_KERNEL, |
1da177e4 LT |
1511 | SECCLASS_SYSTEM, perms, NULL); |
1512 | } | |
1513 | ||
1514 | /* Check whether a task has a particular permission to an inode. | |
1515 | The 'adp' parameter is optional and allows other audit | |
1516 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1517 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1518 | struct inode *inode, |
1519 | u32 perms, | |
1520 | struct avc_audit_data *adp) | |
1521 | { | |
1da177e4 LT |
1522 | struct inode_security_struct *isec; |
1523 | struct avc_audit_data ad; | |
275bb41e | 1524 | u32 sid; |
1da177e4 | 1525 | |
828dfe1d | 1526 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1527 | return 0; |
1528 | ||
88e67f3b | 1529 | sid = cred_sid(cred); |
1da177e4 LT |
1530 | isec = inode->i_security; |
1531 | ||
1532 | if (!adp) { | |
1533 | adp = &ad; | |
1534 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1535 | ad.u.fs.inode = inode; | |
1536 | } | |
1537 | ||
275bb41e | 1538 | return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); |
1da177e4 LT |
1539 | } |
1540 | ||
1541 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1542 | the dentry to help the auditing code to more easily generate the | |
1543 | pathname if needed. */ | |
88e67f3b | 1544 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1545 | struct vfsmount *mnt, |
1546 | struct dentry *dentry, | |
1547 | u32 av) | |
1548 | { | |
1549 | struct inode *inode = dentry->d_inode; | |
1550 | struct avc_audit_data ad; | |
88e67f3b | 1551 | |
828dfe1d | 1552 | AVC_AUDIT_DATA_INIT(&ad, FS); |
44707fdf JB |
1553 | ad.u.fs.path.mnt = mnt; |
1554 | ad.u.fs.path.dentry = dentry; | |
88e67f3b | 1555 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1556 | } |
1557 | ||
1558 | /* Check whether a task can use an open file descriptor to | |
1559 | access an inode in a given way. Check access to the | |
1560 | descriptor itself, and then use dentry_has_perm to | |
1561 | check a particular permission to the file. | |
1562 | Access to the descriptor is implicitly granted if it | |
1563 | has the same SID as the process. If av is zero, then | |
1564 | access to the file is not checked, e.g. for cases | |
1565 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1566 | static int file_has_perm(const struct cred *cred, |
1567 | struct file *file, | |
1568 | u32 av) | |
1da177e4 | 1569 | { |
1da177e4 | 1570 | struct file_security_struct *fsec = file->f_security; |
44707fdf | 1571 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 | 1572 | struct avc_audit_data ad; |
88e67f3b | 1573 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1574 | int rc; |
1575 | ||
1576 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
44707fdf | 1577 | ad.u.fs.path = file->f_path; |
1da177e4 | 1578 | |
275bb41e DH |
1579 | if (sid != fsec->sid) { |
1580 | rc = avc_has_perm(sid, fsec->sid, | |
1da177e4 LT |
1581 | SECCLASS_FD, |
1582 | FD__USE, | |
1583 | &ad); | |
1584 | if (rc) | |
88e67f3b | 1585 | goto out; |
1da177e4 LT |
1586 | } |
1587 | ||
1588 | /* av is zero if only checking access to the descriptor. */ | |
88e67f3b | 1589 | rc = 0; |
1da177e4 | 1590 | if (av) |
88e67f3b | 1591 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1592 | |
88e67f3b DH |
1593 | out: |
1594 | return rc; | |
1da177e4 LT |
1595 | } |
1596 | ||
1597 | /* Check whether a task can create a file. */ | |
1598 | static int may_create(struct inode *dir, | |
1599 | struct dentry *dentry, | |
1600 | u16 tclass) | |
1601 | { | |
275bb41e DH |
1602 | const struct cred *cred = current_cred(); |
1603 | const struct task_security_struct *tsec = cred->security; | |
1da177e4 LT |
1604 | struct inode_security_struct *dsec; |
1605 | struct superblock_security_struct *sbsec; | |
275bb41e | 1606 | u32 sid, newsid; |
1da177e4 LT |
1607 | struct avc_audit_data ad; |
1608 | int rc; | |
1609 | ||
1da177e4 LT |
1610 | dsec = dir->i_security; |
1611 | sbsec = dir->i_sb->s_security; | |
1612 | ||
275bb41e DH |
1613 | sid = tsec->sid; |
1614 | newsid = tsec->create_sid; | |
1615 | ||
1da177e4 | 1616 | AVC_AUDIT_DATA_INIT(&ad, FS); |
44707fdf | 1617 | ad.u.fs.path.dentry = dentry; |
1da177e4 | 1618 | |
275bb41e | 1619 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
1620 | DIR__ADD_NAME | DIR__SEARCH, |
1621 | &ad); | |
1622 | if (rc) | |
1623 | return rc; | |
1624 | ||
cd89596f | 1625 | if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { |
275bb41e | 1626 | rc = security_transition_sid(sid, dsec->sid, tclass, &newsid); |
1da177e4 LT |
1627 | if (rc) |
1628 | return rc; | |
1629 | } | |
1630 | ||
275bb41e | 1631 | rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); |
1da177e4 LT |
1632 | if (rc) |
1633 | return rc; | |
1634 | ||
1635 | return avc_has_perm(newsid, sbsec->sid, | |
1636 | SECCLASS_FILESYSTEM, | |
1637 | FILESYSTEM__ASSOCIATE, &ad); | |
1638 | } | |
1639 | ||
4eb582cf ML |
1640 | /* Check whether a task can create a key. */ |
1641 | static int may_create_key(u32 ksid, | |
1642 | struct task_struct *ctx) | |
1643 | { | |
275bb41e | 1644 | u32 sid = task_sid(ctx); |
4eb582cf | 1645 | |
275bb41e | 1646 | return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); |
4eb582cf ML |
1647 | } |
1648 | ||
828dfe1d EP |
1649 | #define MAY_LINK 0 |
1650 | #define MAY_UNLINK 1 | |
1651 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1652 | |
1653 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1654 | static int may_link(struct inode *dir, | |
1655 | struct dentry *dentry, | |
1656 | int kind) | |
1657 | ||
1658 | { | |
1da177e4 LT |
1659 | struct inode_security_struct *dsec, *isec; |
1660 | struct avc_audit_data ad; | |
275bb41e | 1661 | u32 sid = current_sid(); |
1da177e4 LT |
1662 | u32 av; |
1663 | int rc; | |
1664 | ||
1da177e4 LT |
1665 | dsec = dir->i_security; |
1666 | isec = dentry->d_inode->i_security; | |
1667 | ||
1668 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
44707fdf | 1669 | ad.u.fs.path.dentry = dentry; |
1da177e4 LT |
1670 | |
1671 | av = DIR__SEARCH; | |
1672 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
275bb41e | 1673 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
1674 | if (rc) |
1675 | return rc; | |
1676 | ||
1677 | switch (kind) { | |
1678 | case MAY_LINK: | |
1679 | av = FILE__LINK; | |
1680 | break; | |
1681 | case MAY_UNLINK: | |
1682 | av = FILE__UNLINK; | |
1683 | break; | |
1684 | case MAY_RMDIR: | |
1685 | av = DIR__RMDIR; | |
1686 | break; | |
1687 | default: | |
744ba35e EP |
1688 | printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", |
1689 | __func__, kind); | |
1da177e4 LT |
1690 | return 0; |
1691 | } | |
1692 | ||
275bb41e | 1693 | rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); |
1da177e4 LT |
1694 | return rc; |
1695 | } | |
1696 | ||
1697 | static inline int may_rename(struct inode *old_dir, | |
1698 | struct dentry *old_dentry, | |
1699 | struct inode *new_dir, | |
1700 | struct dentry *new_dentry) | |
1701 | { | |
1da177e4 LT |
1702 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
1703 | struct avc_audit_data ad; | |
275bb41e | 1704 | u32 sid = current_sid(); |
1da177e4 LT |
1705 | u32 av; |
1706 | int old_is_dir, new_is_dir; | |
1707 | int rc; | |
1708 | ||
1da177e4 LT |
1709 | old_dsec = old_dir->i_security; |
1710 | old_isec = old_dentry->d_inode->i_security; | |
1711 | old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); | |
1712 | new_dsec = new_dir->i_security; | |
1713 | ||
1714 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1715 | ||
44707fdf | 1716 | ad.u.fs.path.dentry = old_dentry; |
275bb41e | 1717 | rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
1718 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
1719 | if (rc) | |
1720 | return rc; | |
275bb41e | 1721 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
1722 | old_isec->sclass, FILE__RENAME, &ad); |
1723 | if (rc) | |
1724 | return rc; | |
1725 | if (old_is_dir && new_dir != old_dir) { | |
275bb41e | 1726 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
1727 | old_isec->sclass, DIR__REPARENT, &ad); |
1728 | if (rc) | |
1729 | return rc; | |
1730 | } | |
1731 | ||
44707fdf | 1732 | ad.u.fs.path.dentry = new_dentry; |
1da177e4 LT |
1733 | av = DIR__ADD_NAME | DIR__SEARCH; |
1734 | if (new_dentry->d_inode) | |
1735 | av |= DIR__REMOVE_NAME; | |
275bb41e | 1736 | rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
1737 | if (rc) |
1738 | return rc; | |
1739 | if (new_dentry->d_inode) { | |
1740 | new_isec = new_dentry->d_inode->i_security; | |
1741 | new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); | |
275bb41e | 1742 | rc = avc_has_perm(sid, new_isec->sid, |
1da177e4 LT |
1743 | new_isec->sclass, |
1744 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1745 | if (rc) | |
1746 | return rc; | |
1747 | } | |
1748 | ||
1749 | return 0; | |
1750 | } | |
1751 | ||
1752 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 1753 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
1754 | struct super_block *sb, |
1755 | u32 perms, | |
1756 | struct avc_audit_data *ad) | |
1757 | { | |
1da177e4 | 1758 | struct superblock_security_struct *sbsec; |
88e67f3b | 1759 | u32 sid = cred_sid(cred); |
1da177e4 | 1760 | |
1da177e4 | 1761 | sbsec = sb->s_security; |
275bb41e | 1762 | return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); |
1da177e4 LT |
1763 | } |
1764 | ||
1765 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1766 | static inline u32 file_mask_to_av(int mode, int mask) | |
1767 | { | |
1768 | u32 av = 0; | |
1769 | ||
1770 | if ((mode & S_IFMT) != S_IFDIR) { | |
1771 | if (mask & MAY_EXEC) | |
1772 | av |= FILE__EXECUTE; | |
1773 | if (mask & MAY_READ) | |
1774 | av |= FILE__READ; | |
1775 | ||
1776 | if (mask & MAY_APPEND) | |
1777 | av |= FILE__APPEND; | |
1778 | else if (mask & MAY_WRITE) | |
1779 | av |= FILE__WRITE; | |
1780 | ||
1781 | } else { | |
1782 | if (mask & MAY_EXEC) | |
1783 | av |= DIR__SEARCH; | |
1784 | if (mask & MAY_WRITE) | |
1785 | av |= DIR__WRITE; | |
1786 | if (mask & MAY_READ) | |
1787 | av |= DIR__READ; | |
1788 | } | |
1789 | ||
1790 | return av; | |
1791 | } | |
1792 | ||
8b6a5a37 EP |
1793 | /* Convert a Linux file to an access vector. */ |
1794 | static inline u32 file_to_av(struct file *file) | |
1795 | { | |
1796 | u32 av = 0; | |
1797 | ||
1798 | if (file->f_mode & FMODE_READ) | |
1799 | av |= FILE__READ; | |
1800 | if (file->f_mode & FMODE_WRITE) { | |
1801 | if (file->f_flags & O_APPEND) | |
1802 | av |= FILE__APPEND; | |
1803 | else | |
1804 | av |= FILE__WRITE; | |
1805 | } | |
1806 | if (!av) { | |
1807 | /* | |
1808 | * Special file opened with flags 3 for ioctl-only use. | |
1809 | */ | |
1810 | av = FILE__IOCTL; | |
1811 | } | |
1812 | ||
1813 | return av; | |
1814 | } | |
1815 | ||
b0c636b9 | 1816 | /* |
8b6a5a37 | 1817 | * Convert a file to an access vector and include the correct open |
b0c636b9 EP |
1818 | * open permission. |
1819 | */ | |
8b6a5a37 | 1820 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 1821 | { |
8b6a5a37 | 1822 | u32 av = file_to_av(file); |
b0c636b9 EP |
1823 | |
1824 | if (selinux_policycap_openperm) { | |
8b6a5a37 | 1825 | mode_t mode = file->f_path.dentry->d_inode->i_mode; |
b0c636b9 EP |
1826 | /* |
1827 | * lnk files and socks do not really have an 'open' | |
1828 | */ | |
1829 | if (S_ISREG(mode)) | |
1830 | av |= FILE__OPEN; | |
1831 | else if (S_ISCHR(mode)) | |
1832 | av |= CHR_FILE__OPEN; | |
1833 | else if (S_ISBLK(mode)) | |
1834 | av |= BLK_FILE__OPEN; | |
1835 | else if (S_ISFIFO(mode)) | |
1836 | av |= FIFO_FILE__OPEN; | |
1837 | else if (S_ISDIR(mode)) | |
1838 | av |= DIR__OPEN; | |
1839 | else | |
744ba35e | 1840 | printk(KERN_ERR "SELinux: WARNING: inside %s with " |
8b6a5a37 | 1841 | "unknown mode:%o\n", __func__, mode); |
b0c636b9 EP |
1842 | } |
1843 | return av; | |
1844 | } | |
1845 | ||
1da177e4 LT |
1846 | /* Hook functions begin here. */ |
1847 | ||
5cd9c58f DH |
1848 | static int selinux_ptrace_may_access(struct task_struct *child, |
1849 | unsigned int mode) | |
1da177e4 | 1850 | { |
1da177e4 LT |
1851 | int rc; |
1852 | ||
200ac532 | 1853 | rc = cap_ptrace_may_access(child, mode); |
1da177e4 LT |
1854 | if (rc) |
1855 | return rc; | |
1856 | ||
006ebb40 | 1857 | if (mode == PTRACE_MODE_READ) { |
275bb41e DH |
1858 | u32 sid = current_sid(); |
1859 | u32 csid = task_sid(child); | |
1860 | return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 SS |
1861 | } |
1862 | ||
3b11a1de | 1863 | return current_has_perm(child, PROCESS__PTRACE); |
5cd9c58f DH |
1864 | } |
1865 | ||
1866 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
1867 | { | |
1868 | int rc; | |
1869 | ||
200ac532 | 1870 | rc = cap_ptrace_traceme(parent); |
5cd9c58f DH |
1871 | if (rc) |
1872 | return rc; | |
1873 | ||
1874 | return task_has_perm(parent, current, PROCESS__PTRACE); | |
1da177e4 LT |
1875 | } |
1876 | ||
1877 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 1878 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 LT |
1879 | { |
1880 | int error; | |
1881 | ||
3b11a1de | 1882 | error = current_has_perm(target, PROCESS__GETCAP); |
1da177e4 LT |
1883 | if (error) |
1884 | return error; | |
1885 | ||
200ac532 | 1886 | return cap_capget(target, effective, inheritable, permitted); |
1da177e4 LT |
1887 | } |
1888 | ||
d84f4f99 DH |
1889 | static int selinux_capset(struct cred *new, const struct cred *old, |
1890 | const kernel_cap_t *effective, | |
1891 | const kernel_cap_t *inheritable, | |
1892 | const kernel_cap_t *permitted) | |
1da177e4 LT |
1893 | { |
1894 | int error; | |
1895 | ||
200ac532 | 1896 | error = cap_capset(new, old, |
d84f4f99 | 1897 | effective, inheritable, permitted); |
1da177e4 LT |
1898 | if (error) |
1899 | return error; | |
1900 | ||
d84f4f99 | 1901 | return cred_has_perm(old, new, PROCESS__SETCAP); |
1da177e4 LT |
1902 | } |
1903 | ||
5626d3e8 JM |
1904 | /* |
1905 | * (This comment used to live with the selinux_task_setuid hook, | |
1906 | * which was removed). | |
1907 | * | |
1908 | * Since setuid only affects the current process, and since the SELinux | |
1909 | * controls are not based on the Linux identity attributes, SELinux does not | |
1910 | * need to control this operation. However, SELinux does control the use of | |
1911 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
1912 | */ | |
1913 | ||
3699c53c DH |
1914 | static int selinux_capable(struct task_struct *tsk, const struct cred *cred, |
1915 | int cap, int audit) | |
1da177e4 LT |
1916 | { |
1917 | int rc; | |
1918 | ||
200ac532 | 1919 | rc = cap_capable(tsk, cred, cap, audit); |
1da177e4 LT |
1920 | if (rc) |
1921 | return rc; | |
1922 | ||
3699c53c | 1923 | return task_has_capability(tsk, cred, cap, audit); |
1da177e4 LT |
1924 | } |
1925 | ||
3fbfa981 EB |
1926 | static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid) |
1927 | { | |
1928 | int buflen, rc; | |
1929 | char *buffer, *path, *end; | |
1930 | ||
1931 | rc = -ENOMEM; | |
828dfe1d | 1932 | buffer = (char *)__get_free_page(GFP_KERNEL); |
3fbfa981 EB |
1933 | if (!buffer) |
1934 | goto out; | |
1935 | ||
1936 | buflen = PAGE_SIZE; | |
1937 | end = buffer+buflen; | |
1938 | *--end = '\0'; | |
1939 | buflen--; | |
1940 | path = end-1; | |
1941 | *path = '/'; | |
1942 | while (table) { | |
1943 | const char *name = table->procname; | |
1944 | size_t namelen = strlen(name); | |
1945 | buflen -= namelen + 1; | |
1946 | if (buflen < 0) | |
1947 | goto out_free; | |
1948 | end -= namelen; | |
1949 | memcpy(end, name, namelen); | |
1950 | *--end = '/'; | |
1951 | path = end; | |
1952 | table = table->parent; | |
1953 | } | |
b599fdfd EB |
1954 | buflen -= 4; |
1955 | if (buflen < 0) | |
1956 | goto out_free; | |
1957 | end -= 4; | |
1958 | memcpy(end, "/sys", 4); | |
1959 | path = end; | |
3fbfa981 EB |
1960 | rc = security_genfs_sid("proc", path, tclass, sid); |
1961 | out_free: | |
1962 | free_page((unsigned long)buffer); | |
1963 | out: | |
1964 | return rc; | |
1965 | } | |
1966 | ||
1da177e4 LT |
1967 | static int selinux_sysctl(ctl_table *table, int op) |
1968 | { | |
1969 | int error = 0; | |
1970 | u32 av; | |
275bb41e | 1971 | u32 tsid, sid; |
1da177e4 LT |
1972 | int rc; |
1973 | ||
1974 | rc = secondary_ops->sysctl(table, op); | |
1975 | if (rc) | |
1976 | return rc; | |
1977 | ||
275bb41e | 1978 | sid = current_sid(); |
1da177e4 | 1979 | |
3fbfa981 EB |
1980 | rc = selinux_sysctl_get_sid(table, (op == 0001) ? |
1981 | SECCLASS_DIR : SECCLASS_FILE, &tsid); | |
1da177e4 LT |
1982 | if (rc) { |
1983 | /* Default to the well-defined sysctl SID. */ | |
1984 | tsid = SECINITSID_SYSCTL; | |
1985 | } | |
1986 | ||
1987 | /* The op values are "defined" in sysctl.c, thereby creating | |
1988 | * a bad coupling between this module and sysctl.c */ | |
828dfe1d | 1989 | if (op == 001) { |
275bb41e | 1990 | error = avc_has_perm(sid, tsid, |
1da177e4 LT |
1991 | SECCLASS_DIR, DIR__SEARCH, NULL); |
1992 | } else { | |
1993 | av = 0; | |
1994 | if (op & 004) | |
1995 | av |= FILE__READ; | |
1996 | if (op & 002) | |
1997 | av |= FILE__WRITE; | |
1998 | if (av) | |
275bb41e | 1999 | error = avc_has_perm(sid, tsid, |
1da177e4 | 2000 | SECCLASS_FILE, av, NULL); |
828dfe1d | 2001 | } |
1da177e4 LT |
2002 | |
2003 | return error; | |
2004 | } | |
2005 | ||
2006 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) | |
2007 | { | |
88e67f3b | 2008 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2009 | int rc = 0; |
2010 | ||
2011 | if (!sb) | |
2012 | return 0; | |
2013 | ||
2014 | switch (cmds) { | |
828dfe1d EP |
2015 | case Q_SYNC: |
2016 | case Q_QUOTAON: | |
2017 | case Q_QUOTAOFF: | |
2018 | case Q_SETINFO: | |
2019 | case Q_SETQUOTA: | |
88e67f3b | 2020 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
2021 | break; |
2022 | case Q_GETFMT: | |
2023 | case Q_GETINFO: | |
2024 | case Q_GETQUOTA: | |
88e67f3b | 2025 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
2026 | break; |
2027 | default: | |
2028 | rc = 0; /* let the kernel handle invalid cmds */ | |
2029 | break; | |
1da177e4 LT |
2030 | } |
2031 | return rc; | |
2032 | } | |
2033 | ||
2034 | static int selinux_quota_on(struct dentry *dentry) | |
2035 | { | |
88e67f3b DH |
2036 | const struct cred *cred = current_cred(); |
2037 | ||
2038 | return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON); | |
1da177e4 LT |
2039 | } |
2040 | ||
2041 | static int selinux_syslog(int type) | |
2042 | { | |
2043 | int rc; | |
2044 | ||
200ac532 | 2045 | rc = cap_syslog(type); |
1da177e4 LT |
2046 | if (rc) |
2047 | return rc; | |
2048 | ||
2049 | switch (type) { | |
828dfe1d EP |
2050 | case 3: /* Read last kernel messages */ |
2051 | case 10: /* Return size of the log buffer */ | |
2052 | rc = task_has_system(current, SYSTEM__SYSLOG_READ); | |
2053 | break; | |
2054 | case 6: /* Disable logging to console */ | |
2055 | case 7: /* Enable logging to console */ | |
2056 | case 8: /* Set level of messages printed to console */ | |
2057 | rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); | |
2058 | break; | |
2059 | case 0: /* Close log */ | |
2060 | case 1: /* Open log */ | |
2061 | case 2: /* Read from log */ | |
2062 | case 4: /* Read/clear last kernel messages */ | |
2063 | case 5: /* Clear ring buffer */ | |
2064 | default: | |
2065 | rc = task_has_system(current, SYSTEM__SYSLOG_MOD); | |
2066 | break; | |
1da177e4 LT |
2067 | } |
2068 | return rc; | |
2069 | } | |
2070 | ||
2071 | /* | |
2072 | * Check that a process has enough memory to allocate a new virtual | |
2073 | * mapping. 0 means there is enough memory for the allocation to | |
2074 | * succeed and -ENOMEM implies there is not. | |
2075 | * | |
1da177e4 LT |
2076 | * Do not audit the selinux permission check, as this is applied to all |
2077 | * processes that allocate mappings. | |
2078 | */ | |
34b4e4aa | 2079 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2080 | { |
2081 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2082 | |
3699c53c DH |
2083 | rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN, |
2084 | SECURITY_CAP_NOAUDIT); | |
1da177e4 LT |
2085 | if (rc == 0) |
2086 | cap_sys_admin = 1; | |
2087 | ||
34b4e4aa | 2088 | return __vm_enough_memory(mm, pages, cap_sys_admin); |
1da177e4 LT |
2089 | } |
2090 | ||
2091 | /* binprm security operations */ | |
2092 | ||
a6f76f23 | 2093 | static int selinux_bprm_set_creds(struct linux_binprm *bprm) |
1da177e4 | 2094 | { |
a6f76f23 DH |
2095 | const struct task_security_struct *old_tsec; |
2096 | struct task_security_struct *new_tsec; | |
1da177e4 | 2097 | struct inode_security_struct *isec; |
1da177e4 | 2098 | struct avc_audit_data ad; |
a6f76f23 | 2099 | struct inode *inode = bprm->file->f_path.dentry->d_inode; |
1da177e4 LT |
2100 | int rc; |
2101 | ||
200ac532 | 2102 | rc = cap_bprm_set_creds(bprm); |
1da177e4 LT |
2103 | if (rc) |
2104 | return rc; | |
2105 | ||
a6f76f23 DH |
2106 | /* SELinux context only depends on initial program or script and not |
2107 | * the script interpreter */ | |
2108 | if (bprm->cred_prepared) | |
1da177e4 LT |
2109 | return 0; |
2110 | ||
a6f76f23 DH |
2111 | old_tsec = current_security(); |
2112 | new_tsec = bprm->cred->security; | |
1da177e4 LT |
2113 | isec = inode->i_security; |
2114 | ||
2115 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2116 | new_tsec->sid = old_tsec->sid; |
2117 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2118 | |
28eba5bf | 2119 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2120 | new_tsec->create_sid = 0; |
2121 | new_tsec->keycreate_sid = 0; | |
2122 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2123 | |
a6f76f23 DH |
2124 | if (old_tsec->exec_sid) { |
2125 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2126 | /* Reset exec SID on execve. */ |
a6f76f23 | 2127 | new_tsec->exec_sid = 0; |
1da177e4 LT |
2128 | } else { |
2129 | /* Check for a default transition on this program. */ | |
a6f76f23 DH |
2130 | rc = security_transition_sid(old_tsec->sid, isec->sid, |
2131 | SECCLASS_PROCESS, &new_tsec->sid); | |
1da177e4 LT |
2132 | if (rc) |
2133 | return rc; | |
2134 | } | |
2135 | ||
2136 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
44707fdf | 2137 | ad.u.fs.path = bprm->file->f_path; |
1da177e4 | 2138 | |
3d5ff529 | 2139 | if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) |
a6f76f23 | 2140 | new_tsec->sid = old_tsec->sid; |
1da177e4 | 2141 | |
a6f76f23 DH |
2142 | if (new_tsec->sid == old_tsec->sid) { |
2143 | rc = avc_has_perm(old_tsec->sid, isec->sid, | |
1da177e4 LT |
2144 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2145 | if (rc) | |
2146 | return rc; | |
2147 | } else { | |
2148 | /* Check permissions for the transition. */ | |
a6f76f23 | 2149 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
1da177e4 LT |
2150 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2151 | if (rc) | |
2152 | return rc; | |
2153 | ||
a6f76f23 | 2154 | rc = avc_has_perm(new_tsec->sid, isec->sid, |
1da177e4 LT |
2155 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2156 | if (rc) | |
2157 | return rc; | |
2158 | ||
a6f76f23 DH |
2159 | /* Check for shared state */ |
2160 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
2161 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, | |
2162 | SECCLASS_PROCESS, PROCESS__SHARE, | |
2163 | NULL); | |
2164 | if (rc) | |
2165 | return -EPERM; | |
2166 | } | |
2167 | ||
2168 | /* Make sure that anyone attempting to ptrace over a task that | |
2169 | * changes its SID has the appropriate permit */ | |
2170 | if (bprm->unsafe & | |
2171 | (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { | |
2172 | struct task_struct *tracer; | |
2173 | struct task_security_struct *sec; | |
2174 | u32 ptsid = 0; | |
2175 | ||
2176 | rcu_read_lock(); | |
2177 | tracer = tracehook_tracer_task(current); | |
2178 | if (likely(tracer != NULL)) { | |
2179 | sec = __task_cred(tracer)->security; | |
2180 | ptsid = sec->sid; | |
2181 | } | |
2182 | rcu_read_unlock(); | |
2183 | ||
2184 | if (ptsid != 0) { | |
2185 | rc = avc_has_perm(ptsid, new_tsec->sid, | |
2186 | SECCLASS_PROCESS, | |
2187 | PROCESS__PTRACE, NULL); | |
2188 | if (rc) | |
2189 | return -EPERM; | |
2190 | } | |
2191 | } | |
1da177e4 | 2192 | |
a6f76f23 DH |
2193 | /* Clear any possibly unsafe personality bits on exec: */ |
2194 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
1da177e4 LT |
2195 | } |
2196 | ||
1da177e4 LT |
2197 | return 0; |
2198 | } | |
2199 | ||
828dfe1d | 2200 | static int selinux_bprm_secureexec(struct linux_binprm *bprm) |
1da177e4 | 2201 | { |
275bb41e DH |
2202 | const struct cred *cred = current_cred(); |
2203 | const struct task_security_struct *tsec = cred->security; | |
2204 | u32 sid, osid; | |
1da177e4 LT |
2205 | int atsecure = 0; |
2206 | ||
275bb41e DH |
2207 | sid = tsec->sid; |
2208 | osid = tsec->osid; | |
2209 | ||
2210 | if (osid != sid) { | |
1da177e4 LT |
2211 | /* Enable secure mode for SIDs transitions unless |
2212 | the noatsecure permission is granted between | |
2213 | the two SIDs, i.e. ahp returns 0. */ | |
275bb41e | 2214 | atsecure = avc_has_perm(osid, sid, |
a6f76f23 DH |
2215 | SECCLASS_PROCESS, |
2216 | PROCESS__NOATSECURE, NULL); | |
1da177e4 LT |
2217 | } |
2218 | ||
200ac532 | 2219 | return (atsecure || cap_bprm_secureexec(bprm)); |
1da177e4 LT |
2220 | } |
2221 | ||
1da177e4 LT |
2222 | extern struct vfsmount *selinuxfs_mount; |
2223 | extern struct dentry *selinux_null; | |
2224 | ||
2225 | /* Derived from fs/exec.c:flush_old_files. */ | |
745ca247 DH |
2226 | static inline void flush_unauthorized_files(const struct cred *cred, |
2227 | struct files_struct *files) | |
1da177e4 LT |
2228 | { |
2229 | struct avc_audit_data ad; | |
2230 | struct file *file, *devnull = NULL; | |
b20c8122 | 2231 | struct tty_struct *tty; |
badf1662 | 2232 | struct fdtable *fdt; |
1da177e4 | 2233 | long j = -1; |
24ec839c | 2234 | int drop_tty = 0; |
1da177e4 | 2235 | |
24ec839c | 2236 | tty = get_current_tty(); |
1da177e4 LT |
2237 | if (tty) { |
2238 | file_list_lock(); | |
37dd0bd0 EP |
2239 | if (!list_empty(&tty->tty_files)) { |
2240 | struct inode *inode; | |
2241 | ||
1da177e4 LT |
2242 | /* Revalidate access to controlling tty. |
2243 | Use inode_has_perm on the tty inode directly rather | |
2244 | than using file_has_perm, as this particular open | |
2245 | file may belong to another process and we are only | |
2246 | interested in the inode-based check here. */ | |
37dd0bd0 EP |
2247 | file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list); |
2248 | inode = file->f_path.dentry->d_inode; | |
88e67f3b | 2249 | if (inode_has_perm(cred, inode, |
1da177e4 | 2250 | FILE__READ | FILE__WRITE, NULL)) { |
24ec839c | 2251 | drop_tty = 1; |
1da177e4 LT |
2252 | } |
2253 | } | |
2254 | file_list_unlock(); | |
452a00d2 | 2255 | tty_kref_put(tty); |
1da177e4 | 2256 | } |
98a27ba4 EB |
2257 | /* Reset controlling tty. */ |
2258 | if (drop_tty) | |
2259 | no_tty(); | |
1da177e4 LT |
2260 | |
2261 | /* Revalidate access to inherited open files. */ | |
2262 | ||
828dfe1d | 2263 | AVC_AUDIT_DATA_INIT(&ad, FS); |
1da177e4 LT |
2264 | |
2265 | spin_lock(&files->file_lock); | |
2266 | for (;;) { | |
2267 | unsigned long set, i; | |
2268 | int fd; | |
2269 | ||
2270 | j++; | |
2271 | i = j * __NFDBITS; | |
badf1662 | 2272 | fdt = files_fdtable(files); |
bbea9f69 | 2273 | if (i >= fdt->max_fds) |
1da177e4 | 2274 | break; |
badf1662 | 2275 | set = fdt->open_fds->fds_bits[j]; |
1da177e4 LT |
2276 | if (!set) |
2277 | continue; | |
2278 | spin_unlock(&files->file_lock); | |
828dfe1d | 2279 | for ( ; set ; i++, set >>= 1) { |
1da177e4 LT |
2280 | if (set & 1) { |
2281 | file = fget(i); | |
2282 | if (!file) | |
2283 | continue; | |
88e67f3b | 2284 | if (file_has_perm(cred, |
1da177e4 LT |
2285 | file, |
2286 | file_to_av(file))) { | |
2287 | sys_close(i); | |
2288 | fd = get_unused_fd(); | |
2289 | if (fd != i) { | |
2290 | if (fd >= 0) | |
2291 | put_unused_fd(fd); | |
2292 | fput(file); | |
2293 | continue; | |
2294 | } | |
2295 | if (devnull) { | |
095975da | 2296 | get_file(devnull); |
1da177e4 | 2297 | } else { |
745ca247 DH |
2298 | devnull = dentry_open( |
2299 | dget(selinux_null), | |
2300 | mntget(selinuxfs_mount), | |
2301 | O_RDWR, cred); | |
fc5d81e6 AM |
2302 | if (IS_ERR(devnull)) { |
2303 | devnull = NULL; | |
1da177e4 LT |
2304 | put_unused_fd(fd); |
2305 | fput(file); | |
2306 | continue; | |
2307 | } | |
2308 | } | |
2309 | fd_install(fd, devnull); | |
2310 | } | |
2311 | fput(file); | |
2312 | } | |
2313 | } | |
2314 | spin_lock(&files->file_lock); | |
2315 | ||
2316 | } | |
2317 | spin_unlock(&files->file_lock); | |
2318 | } | |
2319 | ||
a6f76f23 DH |
2320 | /* |
2321 | * Prepare a process for imminent new credential changes due to exec | |
2322 | */ | |
2323 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2324 | { |
a6f76f23 DH |
2325 | struct task_security_struct *new_tsec; |
2326 | struct rlimit *rlim, *initrlim; | |
2327 | int rc, i; | |
d84f4f99 | 2328 | |
a6f76f23 DH |
2329 | new_tsec = bprm->cred->security; |
2330 | if (new_tsec->sid == new_tsec->osid) | |
2331 | return; | |
1da177e4 | 2332 | |
a6f76f23 DH |
2333 | /* Close files for which the new task SID is not authorized. */ |
2334 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2335 | |
a6f76f23 DH |
2336 | /* Always clear parent death signal on SID transitions. */ |
2337 | current->pdeath_signal = 0; | |
0356357c | 2338 | |
a6f76f23 DH |
2339 | /* Check whether the new SID can inherit resource limits from the old |
2340 | * SID. If not, reset all soft limits to the lower of the current | |
2341 | * task's hard limit and the init task's soft limit. | |
2342 | * | |
2343 | * Note that the setting of hard limits (even to lower them) can be | |
2344 | * controlled by the setrlimit check. The inclusion of the init task's | |
2345 | * soft limit into the computation is to avoid resetting soft limits | |
2346 | * higher than the default soft limit for cases where the default is | |
2347 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2348 | */ | |
2349 | rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
2350 | PROCESS__RLIMITINH, NULL); | |
2351 | if (rc) { | |
2352 | for (i = 0; i < RLIM_NLIMITS; i++) { | |
2353 | rlim = current->signal->rlim + i; | |
2354 | initrlim = init_task.signal->rlim + i; | |
2355 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2356 | } |
a6f76f23 | 2357 | update_rlimit_cpu(rlim->rlim_cur); |
1da177e4 LT |
2358 | } |
2359 | } | |
2360 | ||
2361 | /* | |
a6f76f23 DH |
2362 | * Clean up the process immediately after the installation of new credentials |
2363 | * due to exec | |
1da177e4 | 2364 | */ |
a6f76f23 | 2365 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2366 | { |
a6f76f23 | 2367 | const struct task_security_struct *tsec = current_security(); |
1da177e4 | 2368 | struct itimerval itimer; |
41d9f9c5 | 2369 | struct sighand_struct *psig; |
a6f76f23 | 2370 | u32 osid, sid; |
1da177e4 | 2371 | int rc, i; |
41d9f9c5 | 2372 | unsigned long flags; |
1da177e4 | 2373 | |
a6f76f23 DH |
2374 | osid = tsec->osid; |
2375 | sid = tsec->sid; | |
2376 | ||
2377 | if (sid == osid) | |
1da177e4 LT |
2378 | return; |
2379 | ||
a6f76f23 DH |
2380 | /* Check whether the new SID can inherit signal state from the old SID. |
2381 | * If not, clear itimers to avoid subsequent signal generation and | |
2382 | * flush and unblock signals. | |
2383 | * | |
2384 | * This must occur _after_ the task SID has been updated so that any | |
2385 | * kill done after the flush will be checked against the new SID. | |
2386 | */ | |
2387 | rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 LT |
2388 | if (rc) { |
2389 | memset(&itimer, 0, sizeof itimer); | |
2390 | for (i = 0; i < 3; i++) | |
2391 | do_setitimer(i, &itimer, NULL); | |
2392 | flush_signals(current); | |
2393 | spin_lock_irq(¤t->sighand->siglock); | |
2394 | flush_signal_handlers(current, 1); | |
2395 | sigemptyset(¤t->blocked); | |
2396 | recalc_sigpending(); | |
2397 | spin_unlock_irq(¤t->sighand->siglock); | |
2398 | } | |
2399 | ||
a6f76f23 DH |
2400 | /* Wake up the parent if it is waiting so that it can recheck |
2401 | * wait permission to the new task SID. */ | |
41d9f9c5 EP |
2402 | read_lock_irq(&tasklist_lock); |
2403 | psig = current->parent->sighand; | |
2404 | spin_lock_irqsave(&psig->siglock, flags); | |
1da177e4 | 2405 | wake_up_interruptible(¤t->parent->signal->wait_chldexit); |
41d9f9c5 EP |
2406 | spin_unlock_irqrestore(&psig->siglock, flags); |
2407 | read_unlock_irq(&tasklist_lock); | |
1da177e4 LT |
2408 | } |
2409 | ||
2410 | /* superblock security operations */ | |
2411 | ||
2412 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2413 | { | |
2414 | return superblock_alloc_security(sb); | |
2415 | } | |
2416 | ||
2417 | static void selinux_sb_free_security(struct super_block *sb) | |
2418 | { | |
2419 | superblock_free_security(sb); | |
2420 | } | |
2421 | ||
2422 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2423 | { | |
2424 | if (plen > olen) | |
2425 | return 0; | |
2426 | ||
2427 | return !memcmp(prefix, option, plen); | |
2428 | } | |
2429 | ||
2430 | static inline int selinux_option(char *option, int len) | |
2431 | { | |
832cbd9a EP |
2432 | return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || |
2433 | match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || | |
2434 | match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || | |
11689d47 DQ |
2435 | match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || |
2436 | match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); | |
1da177e4 LT |
2437 | } |
2438 | ||
2439 | static inline void take_option(char **to, char *from, int *first, int len) | |
2440 | { | |
2441 | if (!*first) { | |
2442 | **to = ','; | |
2443 | *to += 1; | |
3528a953 | 2444 | } else |
1da177e4 LT |
2445 | *first = 0; |
2446 | memcpy(*to, from, len); | |
2447 | *to += len; | |
2448 | } | |
2449 | ||
828dfe1d EP |
2450 | static inline void take_selinux_option(char **to, char *from, int *first, |
2451 | int len) | |
3528a953 CO |
2452 | { |
2453 | int current_size = 0; | |
2454 | ||
2455 | if (!*first) { | |
2456 | **to = '|'; | |
2457 | *to += 1; | |
828dfe1d | 2458 | } else |
3528a953 CO |
2459 | *first = 0; |
2460 | ||
2461 | while (current_size < len) { | |
2462 | if (*from != '"') { | |
2463 | **to = *from; | |
2464 | *to += 1; | |
2465 | } | |
2466 | from += 1; | |
2467 | current_size += 1; | |
2468 | } | |
2469 | } | |
2470 | ||
e0007529 | 2471 | static int selinux_sb_copy_data(char *orig, char *copy) |
1da177e4 LT |
2472 | { |
2473 | int fnosec, fsec, rc = 0; | |
2474 | char *in_save, *in_curr, *in_end; | |
2475 | char *sec_curr, *nosec_save, *nosec; | |
3528a953 | 2476 | int open_quote = 0; |
1da177e4 LT |
2477 | |
2478 | in_curr = orig; | |
2479 | sec_curr = copy; | |
2480 | ||
1da177e4 LT |
2481 | nosec = (char *)get_zeroed_page(GFP_KERNEL); |
2482 | if (!nosec) { | |
2483 | rc = -ENOMEM; | |
2484 | goto out; | |
2485 | } | |
2486 | ||
2487 | nosec_save = nosec; | |
2488 | fnosec = fsec = 1; | |
2489 | in_save = in_end = orig; | |
2490 | ||
2491 | do { | |
3528a953 CO |
2492 | if (*in_end == '"') |
2493 | open_quote = !open_quote; | |
2494 | if ((*in_end == ',' && open_quote == 0) || | |
2495 | *in_end == '\0') { | |
1da177e4 LT |
2496 | int len = in_end - in_curr; |
2497 | ||
2498 | if (selinux_option(in_curr, len)) | |
3528a953 | 2499 | take_selinux_option(&sec_curr, in_curr, &fsec, len); |
1da177e4 LT |
2500 | else |
2501 | take_option(&nosec, in_curr, &fnosec, len); | |
2502 | ||
2503 | in_curr = in_end + 1; | |
2504 | } | |
2505 | } while (*in_end++); | |
2506 | ||
6931dfc9 | 2507 | strcpy(in_save, nosec_save); |
da3caa20 | 2508 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
2509 | out: |
2510 | return rc; | |
2511 | } | |
2512 | ||
12204e24 | 2513 | static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) |
1da177e4 | 2514 | { |
88e67f3b | 2515 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2516 | struct avc_audit_data ad; |
2517 | int rc; | |
2518 | ||
2519 | rc = superblock_doinit(sb, data); | |
2520 | if (rc) | |
2521 | return rc; | |
2522 | ||
74192246 JM |
2523 | /* Allow all mounts performed by the kernel */ |
2524 | if (flags & MS_KERNMOUNT) | |
2525 | return 0; | |
2526 | ||
828dfe1d | 2527 | AVC_AUDIT_DATA_INIT(&ad, FS); |
44707fdf | 2528 | ad.u.fs.path.dentry = sb->s_root; |
88e67f3b | 2529 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2530 | } |
2531 | ||
726c3342 | 2532 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2533 | { |
88e67f3b | 2534 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2535 | struct avc_audit_data ad; |
2536 | ||
828dfe1d | 2537 | AVC_AUDIT_DATA_INIT(&ad, FS); |
44707fdf | 2538 | ad.u.fs.path.dentry = dentry->d_sb->s_root; |
88e67f3b | 2539 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2540 | } |
2541 | ||
828dfe1d | 2542 | static int selinux_mount(char *dev_name, |
b5266eb4 | 2543 | struct path *path, |
828dfe1d EP |
2544 | char *type, |
2545 | unsigned long flags, | |
2546 | void *data) | |
1da177e4 | 2547 | { |
88e67f3b | 2548 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2549 | |
2550 | if (flags & MS_REMOUNT) | |
88e67f3b | 2551 | return superblock_has_perm(cred, path->mnt->mnt_sb, |
828dfe1d | 2552 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2553 | else |
88e67f3b | 2554 | return dentry_has_perm(cred, path->mnt, path->dentry, |
828dfe1d | 2555 | FILE__MOUNTON); |
1da177e4 LT |
2556 | } |
2557 | ||
2558 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2559 | { | |
88e67f3b | 2560 | const struct cred *cred = current_cred(); |
1da177e4 | 2561 | |
88e67f3b | 2562 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2563 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2564 | } |
2565 | ||
2566 | /* inode security operations */ | |
2567 | ||
2568 | static int selinux_inode_alloc_security(struct inode *inode) | |
2569 | { | |
2570 | return inode_alloc_security(inode); | |
2571 | } | |
2572 | ||
2573 | static void selinux_inode_free_security(struct inode *inode) | |
2574 | { | |
2575 | inode_free_security(inode); | |
2576 | } | |
2577 | ||
5e41ff9e SS |
2578 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
2579 | char **name, void **value, | |
2580 | size_t *len) | |
2581 | { | |
275bb41e DH |
2582 | const struct cred *cred = current_cred(); |
2583 | const struct task_security_struct *tsec = cred->security; | |
5e41ff9e SS |
2584 | struct inode_security_struct *dsec; |
2585 | struct superblock_security_struct *sbsec; | |
275bb41e | 2586 | u32 sid, newsid, clen; |
5e41ff9e | 2587 | int rc; |
570bc1c2 | 2588 | char *namep = NULL, *context; |
5e41ff9e | 2589 | |
5e41ff9e SS |
2590 | dsec = dir->i_security; |
2591 | sbsec = dir->i_sb->s_security; | |
5e41ff9e | 2592 | |
275bb41e DH |
2593 | sid = tsec->sid; |
2594 | newsid = tsec->create_sid; | |
2595 | ||
cd89596f | 2596 | if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { |
275bb41e | 2597 | rc = security_transition_sid(sid, dsec->sid, |
5e41ff9e SS |
2598 | inode_mode_to_security_class(inode->i_mode), |
2599 | &newsid); | |
2600 | if (rc) { | |
2601 | printk(KERN_WARNING "%s: " | |
2602 | "security_transition_sid failed, rc=%d (dev=%s " | |
2603 | "ino=%ld)\n", | |
dd6f953a | 2604 | __func__, |
5e41ff9e SS |
2605 | -rc, inode->i_sb->s_id, inode->i_ino); |
2606 | return rc; | |
2607 | } | |
2608 | } | |
2609 | ||
296fddf7 | 2610 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 2611 | if (sbsec->flags & SE_SBINITIALIZED) { |
296fddf7 EP |
2612 | struct inode_security_struct *isec = inode->i_security; |
2613 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
2614 | isec->sid = newsid; | |
2615 | isec->initialized = 1; | |
2616 | } | |
5e41ff9e | 2617 | |
cd89596f | 2618 | if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP)) |
25a74f3b SS |
2619 | return -EOPNOTSUPP; |
2620 | ||
570bc1c2 | 2621 | if (name) { |
a02fe132 | 2622 | namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); |
570bc1c2 SS |
2623 | if (!namep) |
2624 | return -ENOMEM; | |
2625 | *name = namep; | |
2626 | } | |
5e41ff9e | 2627 | |
570bc1c2 | 2628 | if (value && len) { |
12b29f34 | 2629 | rc = security_sid_to_context_force(newsid, &context, &clen); |
570bc1c2 SS |
2630 | if (rc) { |
2631 | kfree(namep); | |
2632 | return rc; | |
2633 | } | |
2634 | *value = context; | |
2635 | *len = clen; | |
5e41ff9e | 2636 | } |
5e41ff9e | 2637 | |
5e41ff9e SS |
2638 | return 0; |
2639 | } | |
2640 | ||
1da177e4 LT |
2641 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) |
2642 | { | |
2643 | return may_create(dir, dentry, SECCLASS_FILE); | |
2644 | } | |
2645 | ||
1da177e4 LT |
2646 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2647 | { | |
1da177e4 LT |
2648 | return may_link(dir, old_dentry, MAY_LINK); |
2649 | } | |
2650 | ||
1da177e4 LT |
2651 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2652 | { | |
1da177e4 LT |
2653 | return may_link(dir, dentry, MAY_UNLINK); |
2654 | } | |
2655 | ||
2656 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2657 | { | |
2658 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2659 | } | |
2660 | ||
1da177e4 LT |
2661 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) |
2662 | { | |
2663 | return may_create(dir, dentry, SECCLASS_DIR); | |
2664 | } | |
2665 | ||
1da177e4 LT |
2666 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2667 | { | |
2668 | return may_link(dir, dentry, MAY_RMDIR); | |
2669 | } | |
2670 | ||
2671 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) | |
2672 | { | |
1da177e4 LT |
2673 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
2674 | } | |
2675 | ||
1da177e4 | 2676 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 2677 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
2678 | { |
2679 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2680 | } | |
2681 | ||
1da177e4 LT |
2682 | static int selinux_inode_readlink(struct dentry *dentry) |
2683 | { | |
88e67f3b DH |
2684 | const struct cred *cred = current_cred(); |
2685 | ||
2686 | return dentry_has_perm(cred, NULL, dentry, FILE__READ); | |
1da177e4 LT |
2687 | } |
2688 | ||
2689 | static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) | |
2690 | { | |
88e67f3b | 2691 | const struct cred *cred = current_cred(); |
1da177e4 | 2692 | |
88e67f3b | 2693 | return dentry_has_perm(cred, NULL, dentry, FILE__READ); |
1da177e4 LT |
2694 | } |
2695 | ||
b77b0646 | 2696 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 2697 | { |
88e67f3b | 2698 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2699 | |
2700 | if (!mask) { | |
2701 | /* No permission to check. Existence test. */ | |
2702 | return 0; | |
2703 | } | |
2704 | ||
88e67f3b | 2705 | return inode_has_perm(cred, inode, |
8b6a5a37 | 2706 | file_mask_to_av(inode->i_mode, mask), NULL); |
1da177e4 LT |
2707 | } |
2708 | ||
2709 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
2710 | { | |
88e67f3b | 2711 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2712 | |
2713 | if (iattr->ia_valid & ATTR_FORCE) | |
2714 | return 0; | |
2715 | ||
2716 | if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | | |
2717 | ATTR_ATIME_SET | ATTR_MTIME_SET)) | |
88e67f3b | 2718 | return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR); |
1da177e4 | 2719 | |
88e67f3b | 2720 | return dentry_has_perm(cred, NULL, dentry, FILE__WRITE); |
1da177e4 LT |
2721 | } |
2722 | ||
2723 | static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) | |
2724 | { | |
88e67f3b DH |
2725 | const struct cred *cred = current_cred(); |
2726 | ||
2727 | return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR); | |
1da177e4 LT |
2728 | } |
2729 | ||
8f0cfa52 | 2730 | static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) |
b5376771 | 2731 | { |
88e67f3b DH |
2732 | const struct cred *cred = current_cred(); |
2733 | ||
b5376771 SH |
2734 | if (!strncmp(name, XATTR_SECURITY_PREFIX, |
2735 | sizeof XATTR_SECURITY_PREFIX - 1)) { | |
2736 | if (!strcmp(name, XATTR_NAME_CAPS)) { | |
2737 | if (!capable(CAP_SETFCAP)) | |
2738 | return -EPERM; | |
2739 | } else if (!capable(CAP_SYS_ADMIN)) { | |
2740 | /* A different attribute in the security namespace. | |
2741 | Restrict to administrator. */ | |
2742 | return -EPERM; | |
2743 | } | |
2744 | } | |
2745 | ||
2746 | /* Not an attribute we recognize, so just check the | |
2747 | ordinary setattr permission. */ | |
88e67f3b | 2748 | return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR); |
b5376771 SH |
2749 | } |
2750 | ||
8f0cfa52 DH |
2751 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
2752 | const void *value, size_t size, int flags) | |
1da177e4 | 2753 | { |
1da177e4 LT |
2754 | struct inode *inode = dentry->d_inode; |
2755 | struct inode_security_struct *isec = inode->i_security; | |
2756 | struct superblock_security_struct *sbsec; | |
2757 | struct avc_audit_data ad; | |
275bb41e | 2758 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
2759 | int rc = 0; |
2760 | ||
b5376771 SH |
2761 | if (strcmp(name, XATTR_NAME_SELINUX)) |
2762 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
2763 | |
2764 | sbsec = inode->i_sb->s_security; | |
cd89596f | 2765 | if (!(sbsec->flags & SE_SBLABELSUPP)) |
1da177e4 LT |
2766 | return -EOPNOTSUPP; |
2767 | ||
3bd858ab | 2768 | if (!is_owner_or_cap(inode)) |
1da177e4 LT |
2769 | return -EPERM; |
2770 | ||
828dfe1d | 2771 | AVC_AUDIT_DATA_INIT(&ad, FS); |
44707fdf | 2772 | ad.u.fs.path.dentry = dentry; |
1da177e4 | 2773 | |
275bb41e | 2774 | rc = avc_has_perm(sid, isec->sid, isec->sclass, |
1da177e4 LT |
2775 | FILE__RELABELFROM, &ad); |
2776 | if (rc) | |
2777 | return rc; | |
2778 | ||
2779 | rc = security_context_to_sid(value, size, &newsid); | |
12b29f34 SS |
2780 | if (rc == -EINVAL) { |
2781 | if (!capable(CAP_MAC_ADMIN)) | |
2782 | return rc; | |
2783 | rc = security_context_to_sid_force(value, size, &newsid); | |
2784 | } | |
1da177e4 LT |
2785 | if (rc) |
2786 | return rc; | |
2787 | ||
275bb41e | 2788 | rc = avc_has_perm(sid, newsid, isec->sclass, |
1da177e4 LT |
2789 | FILE__RELABELTO, &ad); |
2790 | if (rc) | |
2791 | return rc; | |
2792 | ||
275bb41e | 2793 | rc = security_validate_transition(isec->sid, newsid, sid, |
828dfe1d | 2794 | isec->sclass); |
1da177e4 LT |
2795 | if (rc) |
2796 | return rc; | |
2797 | ||
2798 | return avc_has_perm(newsid, | |
2799 | sbsec->sid, | |
2800 | SECCLASS_FILESYSTEM, | |
2801 | FILESYSTEM__ASSOCIATE, | |
2802 | &ad); | |
2803 | } | |
2804 | ||
8f0cfa52 | 2805 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 2806 | const void *value, size_t size, |
8f0cfa52 | 2807 | int flags) |
1da177e4 LT |
2808 | { |
2809 | struct inode *inode = dentry->d_inode; | |
2810 | struct inode_security_struct *isec = inode->i_security; | |
2811 | u32 newsid; | |
2812 | int rc; | |
2813 | ||
2814 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
2815 | /* Not an attribute we recognize, so nothing to do. */ | |
2816 | return; | |
2817 | } | |
2818 | ||
12b29f34 | 2819 | rc = security_context_to_sid_force(value, size, &newsid); |
1da177e4 | 2820 | if (rc) { |
12b29f34 SS |
2821 | printk(KERN_ERR "SELinux: unable to map context to SID" |
2822 | "for (%s, %lu), rc=%d\n", | |
2823 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
2824 | return; |
2825 | } | |
2826 | ||
2827 | isec->sid = newsid; | |
2828 | return; | |
2829 | } | |
2830 | ||
8f0cfa52 | 2831 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 2832 | { |
88e67f3b DH |
2833 | const struct cred *cred = current_cred(); |
2834 | ||
2835 | return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR); | |
1da177e4 LT |
2836 | } |
2837 | ||
828dfe1d | 2838 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 2839 | { |
88e67f3b DH |
2840 | const struct cred *cred = current_cred(); |
2841 | ||
2842 | return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR); | |
1da177e4 LT |
2843 | } |
2844 | ||
8f0cfa52 | 2845 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 2846 | { |
b5376771 SH |
2847 | if (strcmp(name, XATTR_NAME_SELINUX)) |
2848 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
2849 | |
2850 | /* No one is allowed to remove a SELinux security label. | |
2851 | You can change the label, but all data must be labeled. */ | |
2852 | return -EACCES; | |
2853 | } | |
2854 | ||
d381d8a9 | 2855 | /* |
abc69bb6 | 2856 | * Copy the inode security context value to the user. |
d381d8a9 JM |
2857 | * |
2858 | * Permission check is handled by selinux_inode_getxattr hook. | |
2859 | */ | |
42492594 | 2860 | static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 2861 | { |
42492594 DQ |
2862 | u32 size; |
2863 | int error; | |
2864 | char *context = NULL; | |
1da177e4 | 2865 | struct inode_security_struct *isec = inode->i_security; |
d381d8a9 | 2866 | |
8c8570fb DK |
2867 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
2868 | return -EOPNOTSUPP; | |
d381d8a9 | 2869 | |
abc69bb6 SS |
2870 | /* |
2871 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
2872 | * value even if it is not defined by current policy; otherwise, | |
2873 | * use the in-core value under current policy. | |
2874 | * Use the non-auditing forms of the permission checks since | |
2875 | * getxattr may be called by unprivileged processes commonly | |
2876 | * and lack of permission just means that we fall back to the | |
2877 | * in-core context value, not a denial. | |
2878 | */ | |
3699c53c DH |
2879 | error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN, |
2880 | SECURITY_CAP_NOAUDIT); | |
abc69bb6 SS |
2881 | if (!error) |
2882 | error = security_sid_to_context_force(isec->sid, &context, | |
2883 | &size); | |
2884 | else | |
2885 | error = security_sid_to_context(isec->sid, &context, &size); | |
42492594 DQ |
2886 | if (error) |
2887 | return error; | |
2888 | error = size; | |
2889 | if (alloc) { | |
2890 | *buffer = context; | |
2891 | goto out_nofree; | |
2892 | } | |
2893 | kfree(context); | |
2894 | out_nofree: | |
2895 | return error; | |
1da177e4 LT |
2896 | } |
2897 | ||
2898 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 2899 | const void *value, size_t size, int flags) |
1da177e4 LT |
2900 | { |
2901 | struct inode_security_struct *isec = inode->i_security; | |
2902 | u32 newsid; | |
2903 | int rc; | |
2904 | ||
2905 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
2906 | return -EOPNOTSUPP; | |
2907 | ||
2908 | if (!value || !size) | |
2909 | return -EACCES; | |
2910 | ||
828dfe1d | 2911 | rc = security_context_to_sid((void *)value, size, &newsid); |
1da177e4 LT |
2912 | if (rc) |
2913 | return rc; | |
2914 | ||
2915 | isec->sid = newsid; | |
2916 | return 0; | |
2917 | } | |
2918 | ||
2919 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
2920 | { | |
2921 | const int len = sizeof(XATTR_NAME_SELINUX); | |
2922 | if (buffer && len <= buffer_size) | |
2923 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
2924 | return len; | |
2925 | } | |
2926 | ||
713a04ae AD |
2927 | static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) |
2928 | { | |
2929 | struct inode_security_struct *isec = inode->i_security; | |
2930 | *secid = isec->sid; | |
2931 | } | |
2932 | ||
1da177e4 LT |
2933 | /* file security operations */ |
2934 | ||
788e7dd4 | 2935 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 2936 | { |
88e67f3b | 2937 | const struct cred *cred = current_cred(); |
7420ed23 | 2938 | int rc; |
3d5ff529 | 2939 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
2940 | |
2941 | if (!mask) { | |
2942 | /* No permission to check. Existence test. */ | |
2943 | return 0; | |
2944 | } | |
2945 | ||
2946 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ | |
2947 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
2948 | mask |= MAY_APPEND; | |
2949 | ||
88e67f3b | 2950 | rc = file_has_perm(cred, file, |
7420ed23 VY |
2951 | file_mask_to_av(inode->i_mode, mask)); |
2952 | if (rc) | |
2953 | return rc; | |
2954 | ||
2955 | return selinux_netlbl_inode_permission(inode, mask); | |
1da177e4 LT |
2956 | } |
2957 | ||
788e7dd4 YN |
2958 | static int selinux_file_permission(struct file *file, int mask) |
2959 | { | |
2960 | struct inode *inode = file->f_path.dentry->d_inode; | |
788e7dd4 YN |
2961 | struct file_security_struct *fsec = file->f_security; |
2962 | struct inode_security_struct *isec = inode->i_security; | |
275bb41e | 2963 | u32 sid = current_sid(); |
788e7dd4 YN |
2964 | |
2965 | if (!mask) { | |
2966 | /* No permission to check. Existence test. */ | |
2967 | return 0; | |
2968 | } | |
2969 | ||
275bb41e | 2970 | if (sid == fsec->sid && fsec->isid == isec->sid |
788e7dd4 YN |
2971 | && fsec->pseqno == avc_policy_seqno()) |
2972 | return selinux_netlbl_inode_permission(inode, mask); | |
2973 | ||
2974 | return selinux_revalidate_file_permission(file, mask); | |
2975 | } | |
2976 | ||
1da177e4 LT |
2977 | static int selinux_file_alloc_security(struct file *file) |
2978 | { | |
2979 | return file_alloc_security(file); | |
2980 | } | |
2981 | ||
2982 | static void selinux_file_free_security(struct file *file) | |
2983 | { | |
2984 | file_free_security(file); | |
2985 | } | |
2986 | ||
2987 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, | |
2988 | unsigned long arg) | |
2989 | { | |
88e67f3b | 2990 | const struct cred *cred = current_cred(); |
242631c4 | 2991 | u32 av = 0; |
1da177e4 | 2992 | |
242631c4 SS |
2993 | if (_IOC_DIR(cmd) & _IOC_WRITE) |
2994 | av |= FILE__WRITE; | |
2995 | if (_IOC_DIR(cmd) & _IOC_READ) | |
2996 | av |= FILE__READ; | |
2997 | if (!av) | |
2998 | av = FILE__IOCTL; | |
1da177e4 | 2999 | |
88e67f3b | 3000 | return file_has_perm(cred, file, av); |
1da177e4 LT |
3001 | } |
3002 | ||
3003 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) | |
3004 | { | |
88e67f3b | 3005 | const struct cred *cred = current_cred(); |
d84f4f99 | 3006 | int rc = 0; |
88e67f3b | 3007 | |
1da177e4 LT |
3008 | #ifndef CONFIG_PPC32 |
3009 | if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { | |
3010 | /* | |
3011 | * We are making executable an anonymous mapping or a | |
3012 | * private file mapping that will also be writable. | |
3013 | * This has an additional check. | |
3014 | */ | |
d84f4f99 | 3015 | rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); |
1da177e4 | 3016 | if (rc) |
d84f4f99 | 3017 | goto error; |
1da177e4 LT |
3018 | } |
3019 | #endif | |
3020 | ||
3021 | if (file) { | |
3022 | /* read access is always possible with a mapping */ | |
3023 | u32 av = FILE__READ; | |
3024 | ||
3025 | /* write access only matters if the mapping is shared */ | |
3026 | if (shared && (prot & PROT_WRITE)) | |
3027 | av |= FILE__WRITE; | |
3028 | ||
3029 | if (prot & PROT_EXEC) | |
3030 | av |= FILE__EXECUTE; | |
3031 | ||
88e67f3b | 3032 | return file_has_perm(cred, file, av); |
1da177e4 | 3033 | } |
d84f4f99 DH |
3034 | |
3035 | error: | |
3036 | return rc; | |
1da177e4 LT |
3037 | } |
3038 | ||
3039 | static int selinux_file_mmap(struct file *file, unsigned long reqprot, | |
ed032189 EP |
3040 | unsigned long prot, unsigned long flags, |
3041 | unsigned long addr, unsigned long addr_only) | |
1da177e4 | 3042 | { |
ed032189 | 3043 | int rc = 0; |
275bb41e | 3044 | u32 sid = current_sid(); |
1da177e4 | 3045 | |
ed032189 EP |
3046 | if (addr < mmap_min_addr) |
3047 | rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, | |
3048 | MEMPROTECT__MMAP_ZERO, NULL); | |
3049 | if (rc || addr_only) | |
1da177e4 LT |
3050 | return rc; |
3051 | ||
3052 | if (selinux_checkreqprot) | |
3053 | prot = reqprot; | |
3054 | ||
3055 | return file_map_prot_check(file, prot, | |
3056 | (flags & MAP_TYPE) == MAP_SHARED); | |
3057 | } | |
3058 | ||
3059 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3060 | unsigned long reqprot, | |
3061 | unsigned long prot) | |
3062 | { | |
88e67f3b | 3063 | const struct cred *cred = current_cred(); |
1da177e4 LT |
3064 | |
3065 | if (selinux_checkreqprot) | |
3066 | prot = reqprot; | |
3067 | ||
3068 | #ifndef CONFIG_PPC32 | |
db4c9641 | 3069 | if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { |
d541bbee | 3070 | int rc = 0; |
db4c9641 SS |
3071 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3072 | vma->vm_end <= vma->vm_mm->brk) { | |
d84f4f99 | 3073 | rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); |
db4c9641 SS |
3074 | } else if (!vma->vm_file && |
3075 | vma->vm_start <= vma->vm_mm->start_stack && | |
3076 | vma->vm_end >= vma->vm_mm->start_stack) { | |
3b11a1de | 3077 | rc = current_has_perm(current, PROCESS__EXECSTACK); |
db4c9641 SS |
3078 | } else if (vma->vm_file && vma->anon_vma) { |
3079 | /* | |
3080 | * We are making executable a file mapping that has | |
3081 | * had some COW done. Since pages might have been | |
3082 | * written, check ability to execute the possibly | |
3083 | * modified content. This typically should only | |
3084 | * occur for text relocations. | |
3085 | */ | |
d84f4f99 | 3086 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3087 | } |