Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * NSA Security-Enhanced Linux (SELinux) security module | |
3 | * | |
4 | * This file contains the SELinux hook function implementations. | |
5 | * | |
6 | * Authors: Stephen Smalley, <sds@epoch.ncsc.mil> | |
828dfe1d EP |
7 | * Chris Vance, <cvance@nai.com> |
8 | * Wayne Salamon, <wsalamon@nai.com> | |
9 | * James Morris <jmorris@redhat.com> | |
1da177e4 LT |
10 | * |
11 | * Copyright (C) 2001,2002 Networks Associates Technology, Inc. | |
2069f457 EP |
12 | * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> |
13 | * Eric Paris <eparis@redhat.com> | |
1da177e4 | 14 | * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. |
828dfe1d | 15 | * <dgoeddel@trustedcs.com> |
ed6d76e4 | 16 | * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. |
82c21bfa | 17 | * Paul Moore <paul@paul-moore.com> |
788e7dd4 | 18 | * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. |
828dfe1d | 19 | * Yuichi Nakamura <ynakam@hitachisoft.jp> |
1da177e4 LT |
20 | * |
21 | * This program is free software; you can redistribute it and/or modify | |
22 | * it under the terms of the GNU General Public License version 2, | |
828dfe1d | 23 | * as published by the Free Software Foundation. |
1da177e4 LT |
24 | */ |
25 | ||
1da177e4 | 26 | #include <linux/init.h> |
0b24dcb7 | 27 | #include <linux/kd.h> |
1da177e4 | 28 | #include <linux/kernel.h> |
0d094efe | 29 | #include <linux/tracehook.h> |
1da177e4 LT |
30 | #include <linux/errno.h> |
31 | #include <linux/sched.h> | |
32 | #include <linux/security.h> | |
33 | #include <linux/xattr.h> | |
34 | #include <linux/capability.h> | |
35 | #include <linux/unistd.h> | |
36 | #include <linux/mm.h> | |
37 | #include <linux/mman.h> | |
38 | #include <linux/slab.h> | |
39 | #include <linux/pagemap.h> | |
0b24dcb7 | 40 | #include <linux/proc_fs.h> |
1da177e4 | 41 | #include <linux/swap.h> |
1da177e4 LT |
42 | #include <linux/spinlock.h> |
43 | #include <linux/syscalls.h> | |
2a7dba39 | 44 | #include <linux/dcache.h> |
1da177e4 | 45 | #include <linux/file.h> |
9f3acc31 | 46 | #include <linux/fdtable.h> |
1da177e4 LT |
47 | #include <linux/namei.h> |
48 | #include <linux/mount.h> | |
1da177e4 LT |
49 | #include <linux/netfilter_ipv4.h> |
50 | #include <linux/netfilter_ipv6.h> | |
51 | #include <linux/tty.h> | |
52 | #include <net/icmp.h> | |
227b60f5 | 53 | #include <net/ip.h> /* for local_port_range[] */ |
ca10b9e9 | 54 | #include <net/sock.h> |
1da177e4 | 55 | #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ |
220deb96 | 56 | #include <net/net_namespace.h> |
d621d35e | 57 | #include <net/netlabel.h> |
f5269710 | 58 | #include <linux/uaccess.h> |
1da177e4 | 59 | #include <asm/ioctls.h> |
60063497 | 60 | #include <linux/atomic.h> |
1da177e4 LT |
61 | #include <linux/bitops.h> |
62 | #include <linux/interrupt.h> | |
63 | #include <linux/netdevice.h> /* for network interface checks */ | |
77954983 | 64 | #include <net/netlink.h> |
1da177e4 LT |
65 | #include <linux/tcp.h> |
66 | #include <linux/udp.h> | |
2ee92d46 | 67 | #include <linux/dccp.h> |
1da177e4 LT |
68 | #include <linux/quota.h> |
69 | #include <linux/un.h> /* for Unix socket types */ | |
70 | #include <net/af_unix.h> /* for Unix socket types */ | |
71 | #include <linux/parser.h> | |
72 | #include <linux/nfs_mount.h> | |
73 | #include <net/ipv6.h> | |
74 | #include <linux/hugetlb.h> | |
75 | #include <linux/personality.h> | |
1da177e4 | 76 | #include <linux/audit.h> |
6931dfc9 | 77 | #include <linux/string.h> |
877ce7c1 | 78 | #include <linux/selinux.h> |
23970741 | 79 | #include <linux/mutex.h> |
f06febc9 | 80 | #include <linux/posix-timers.h> |
00234592 | 81 | #include <linux/syslog.h> |
3486740a | 82 | #include <linux/user_namespace.h> |
44fc7ea0 | 83 | #include <linux/export.h> |
eb9ae686 | 84 | #include <linux/security.h> |
40401530 AV |
85 | #include <linux/msg.h> |
86 | #include <linux/shm.h> | |
1da177e4 LT |
87 | |
88 | #include "avc.h" | |
89 | #include "objsec.h" | |
90 | #include "netif.h" | |
224dfbd8 | 91 | #include "netnode.h" |
3e112172 | 92 | #include "netport.h" |
d28d1e08 | 93 | #include "xfrm.h" |
c60475bf | 94 | #include "netlabel.h" |
9d57a7f9 | 95 | #include "audit.h" |
7b98a585 | 96 | #include "avc_ss.h" |
1da177e4 | 97 | |
11689d47 | 98 | #define NUM_SEL_MNT_OPTS 5 |
c9180a57 | 99 | |
20510f2f | 100 | extern struct security_operations *security_ops; |
1da177e4 | 101 | |
d621d35e | 102 | /* SECMARK reference count */ |
56a4ca99 | 103 | static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); |
d621d35e | 104 | |
1da177e4 | 105 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
828dfe1d | 106 | int selinux_enforcing; |
1da177e4 LT |
107 | |
108 | static int __init enforcing_setup(char *str) | |
109 | { | |
f5269710 EP |
110 | unsigned long enforcing; |
111 | if (!strict_strtoul(str, 0, &enforcing)) | |
112 | selinux_enforcing = enforcing ? 1 : 0; | |
1da177e4 LT |
113 | return 1; |
114 | } | |
115 | __setup("enforcing=", enforcing_setup); | |
116 | #endif | |
117 | ||
118 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM | |
119 | int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; | |
120 | ||
121 | static int __init selinux_enabled_setup(char *str) | |
122 | { | |
f5269710 EP |
123 | unsigned long enabled; |
124 | if (!strict_strtoul(str, 0, &enabled)) | |
125 | selinux_enabled = enabled ? 1 : 0; | |
1da177e4 LT |
126 | return 1; |
127 | } | |
128 | __setup("selinux=", selinux_enabled_setup); | |
30d55280 SS |
129 | #else |
130 | int selinux_enabled = 1; | |
1da177e4 LT |
131 | #endif |
132 | ||
e18b890b | 133 | static struct kmem_cache *sel_inode_cache; |
7cae7e26 | 134 | |
d621d35e PM |
135 | /** |
136 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
137 | * | |
138 | * Description: | |
139 | * This function checks the SECMARK reference counter to see if any SECMARK | |
140 | * targets are currently configured, if the reference counter is greater than | |
141 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
142 | * enabled, false (0) if SECMARK is disabled. | |
143 | * | |
144 | */ | |
145 | static int selinux_secmark_enabled(void) | |
146 | { | |
147 | return (atomic_read(&selinux_secmark_refcount) > 0); | |
148 | } | |
149 | ||
d84f4f99 DH |
150 | /* |
151 | * initialise the security for the init task | |
152 | */ | |
153 | static void cred_init_security(void) | |
1da177e4 | 154 | { |
3b11a1de | 155 | struct cred *cred = (struct cred *) current->real_cred; |
1da177e4 LT |
156 | struct task_security_struct *tsec; |
157 | ||
89d155ef | 158 | tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); |
1da177e4 | 159 | if (!tsec) |
d84f4f99 | 160 | panic("SELinux: Failed to initialize initial task.\n"); |
1da177e4 | 161 | |
d84f4f99 | 162 | tsec->osid = tsec->sid = SECINITSID_KERNEL; |
f1752eec | 163 | cred->security = tsec; |
1da177e4 LT |
164 | } |
165 | ||
88e67f3b DH |
166 | /* |
167 | * get the security ID of a set of credentials | |
168 | */ | |
169 | static inline u32 cred_sid(const struct cred *cred) | |
170 | { | |
171 | const struct task_security_struct *tsec; | |
172 | ||
173 | tsec = cred->security; | |
174 | return tsec->sid; | |
175 | } | |
176 | ||
275bb41e | 177 | /* |
3b11a1de | 178 | * get the objective security ID of a task |
275bb41e DH |
179 | */ |
180 | static inline u32 task_sid(const struct task_struct *task) | |
181 | { | |
275bb41e DH |
182 | u32 sid; |
183 | ||
184 | rcu_read_lock(); | |
88e67f3b | 185 | sid = cred_sid(__task_cred(task)); |
275bb41e DH |
186 | rcu_read_unlock(); |
187 | return sid; | |
188 | } | |
189 | ||
190 | /* | |
3b11a1de | 191 | * get the subjective security ID of the current task |
275bb41e DH |
192 | */ |
193 | static inline u32 current_sid(void) | |
194 | { | |
5fb49870 | 195 | const struct task_security_struct *tsec = current_security(); |
275bb41e DH |
196 | |
197 | return tsec->sid; | |
198 | } | |
199 | ||
88e67f3b DH |
200 | /* Allocate and free functions for each kind of security blob. */ |
201 | ||
1da177e4 LT |
202 | static int inode_alloc_security(struct inode *inode) |
203 | { | |
1da177e4 | 204 | struct inode_security_struct *isec; |
275bb41e | 205 | u32 sid = current_sid(); |
1da177e4 | 206 | |
a02fe132 | 207 | isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); |
1da177e4 LT |
208 | if (!isec) |
209 | return -ENOMEM; | |
210 | ||
23970741 | 211 | mutex_init(&isec->lock); |
1da177e4 | 212 | INIT_LIST_HEAD(&isec->list); |
1da177e4 LT |
213 | isec->inode = inode; |
214 | isec->sid = SECINITSID_UNLABELED; | |
215 | isec->sclass = SECCLASS_FILE; | |
275bb41e | 216 | isec->task_sid = sid; |
1da177e4 LT |
217 | inode->i_security = isec; |
218 | ||
219 | return 0; | |
220 | } | |
221 | ||
222 | static void inode_free_security(struct inode *inode) | |
223 | { | |
224 | struct inode_security_struct *isec = inode->i_security; | |
225 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
226 | ||
1da177e4 LT |
227 | spin_lock(&sbsec->isec_lock); |
228 | if (!list_empty(&isec->list)) | |
229 | list_del_init(&isec->list); | |
230 | spin_unlock(&sbsec->isec_lock); | |
231 | ||
232 | inode->i_security = NULL; | |
7cae7e26 | 233 | kmem_cache_free(sel_inode_cache, isec); |
1da177e4 LT |
234 | } |
235 | ||
236 | static int file_alloc_security(struct file *file) | |
237 | { | |
1da177e4 | 238 | struct file_security_struct *fsec; |
275bb41e | 239 | u32 sid = current_sid(); |
1da177e4 | 240 | |
26d2a4be | 241 | fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); |
1da177e4 LT |
242 | if (!fsec) |
243 | return -ENOMEM; | |
244 | ||
275bb41e DH |
245 | fsec->sid = sid; |
246 | fsec->fown_sid = sid; | |
1da177e4 LT |
247 | file->f_security = fsec; |
248 | ||
249 | return 0; | |
250 | } | |
251 | ||
252 | static void file_free_security(struct file *file) | |
253 | { | |
254 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 LT |
255 | file->f_security = NULL; |
256 | kfree(fsec); | |
257 | } | |
258 | ||
259 | static int superblock_alloc_security(struct super_block *sb) | |
260 | { | |
261 | struct superblock_security_struct *sbsec; | |
262 | ||
89d155ef | 263 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
264 | if (!sbsec) |
265 | return -ENOMEM; | |
266 | ||
bc7e982b | 267 | mutex_init(&sbsec->lock); |
1da177e4 LT |
268 | INIT_LIST_HEAD(&sbsec->isec_head); |
269 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
270 | sbsec->sb = sb; |
271 | sbsec->sid = SECINITSID_UNLABELED; | |
272 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 273 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
274 | sb->s_security = sbsec; |
275 | ||
276 | return 0; | |
277 | } | |
278 | ||
279 | static void superblock_free_security(struct super_block *sb) | |
280 | { | |
281 | struct superblock_security_struct *sbsec = sb->s_security; | |
1da177e4 LT |
282 | sb->s_security = NULL; |
283 | kfree(sbsec); | |
284 | } | |
285 | ||
1da177e4 LT |
286 | /* The file system's label must be initialized prior to use. */ |
287 | ||
eb9ae686 | 288 | static const char *labeling_behaviors[7] = { |
1da177e4 LT |
289 | "uses xattr", |
290 | "uses transition SIDs", | |
291 | "uses task SIDs", | |
292 | "uses genfs_contexts", | |
293 | "not configured for labeling", | |
294 | "uses mountpoint labeling", | |
eb9ae686 | 295 | "uses native labeling", |
1da177e4 LT |
296 | }; |
297 | ||
298 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); | |
299 | ||
300 | static inline int inode_doinit(struct inode *inode) | |
301 | { | |
302 | return inode_doinit_with_dentry(inode, NULL); | |
303 | } | |
304 | ||
305 | enum { | |
31e87930 | 306 | Opt_error = -1, |
1da177e4 LT |
307 | Opt_context = 1, |
308 | Opt_fscontext = 2, | |
c9180a57 EP |
309 | Opt_defcontext = 3, |
310 | Opt_rootcontext = 4, | |
11689d47 | 311 | Opt_labelsupport = 5, |
1da177e4 LT |
312 | }; |
313 | ||
a447c093 | 314 | static const match_table_t tokens = { |
832cbd9a EP |
315 | {Opt_context, CONTEXT_STR "%s"}, |
316 | {Opt_fscontext, FSCONTEXT_STR "%s"}, | |
317 | {Opt_defcontext, DEFCONTEXT_STR "%s"}, | |
318 | {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, | |
11689d47 | 319 | {Opt_labelsupport, LABELSUPP_STR}, |
31e87930 | 320 | {Opt_error, NULL}, |
1da177e4 LT |
321 | }; |
322 | ||
323 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
324 | ||
c312feb2 EP |
325 | static int may_context_mount_sb_relabel(u32 sid, |
326 | struct superblock_security_struct *sbsec, | |
275bb41e | 327 | const struct cred *cred) |
c312feb2 | 328 | { |
275bb41e | 329 | const struct task_security_struct *tsec = cred->security; |
c312feb2 EP |
330 | int rc; |
331 | ||
332 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
333 | FILESYSTEM__RELABELFROM, NULL); | |
334 | if (rc) | |
335 | return rc; | |
336 | ||
337 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, | |
338 | FILESYSTEM__RELABELTO, NULL); | |
339 | return rc; | |
340 | } | |
341 | ||
0808925e EP |
342 | static int may_context_mount_inode_relabel(u32 sid, |
343 | struct superblock_security_struct *sbsec, | |
275bb41e | 344 | const struct cred *cred) |
0808925e | 345 | { |
275bb41e | 346 | const struct task_security_struct *tsec = cred->security; |
0808925e EP |
347 | int rc; |
348 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
349 | FILESYSTEM__RELABELFROM, NULL); | |
350 | if (rc) | |
351 | return rc; | |
352 | ||
353 | rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
354 | FILESYSTEM__ASSOCIATE, NULL); | |
355 | return rc; | |
356 | } | |
357 | ||
c9180a57 | 358 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 359 | { |
1da177e4 | 360 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 EP |
361 | struct dentry *root = sb->s_root; |
362 | struct inode *root_inode = root->d_inode; | |
363 | int rc = 0; | |
1da177e4 | 364 | |
c9180a57 EP |
365 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
366 | /* Make sure that the xattr handler exists and that no | |
367 | error other than -ENODATA is returned by getxattr on | |
368 | the root directory. -ENODATA is ok, as this may be | |
369 | the first boot of the SELinux kernel before we have | |
370 | assigned xattr values to the filesystem. */ | |
371 | if (!root_inode->i_op->getxattr) { | |
372 | printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " | |
373 | "xattr support\n", sb->s_id, sb->s_type->name); | |
374 | rc = -EOPNOTSUPP; | |
375 | goto out; | |
376 | } | |
377 | rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); | |
378 | if (rc < 0 && rc != -ENODATA) { | |
379 | if (rc == -EOPNOTSUPP) | |
380 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
381 | "%s) has no security xattr handler\n", | |
382 | sb->s_id, sb->s_type->name); | |
383 | else | |
384 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
385 | "%s) getxattr errno %d\n", sb->s_id, | |
386 | sb->s_type->name, -rc); | |
387 | goto out; | |
388 | } | |
389 | } | |
1da177e4 | 390 | |
11689d47 | 391 | sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP); |
1da177e4 | 392 | |
c9180a57 EP |
393 | if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) |
394 | printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", | |
395 | sb->s_id, sb->s_type->name); | |
396 | else | |
397 | printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", | |
398 | sb->s_id, sb->s_type->name, | |
399 | labeling_behaviors[sbsec->behavior-1]); | |
1da177e4 | 400 | |
11689d47 DQ |
401 | if (sbsec->behavior == SECURITY_FS_USE_GENFS || |
402 | sbsec->behavior == SECURITY_FS_USE_MNTPOINT || | |
403 | sbsec->behavior == SECURITY_FS_USE_NONE || | |
404 | sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) | |
405 | sbsec->flags &= ~SE_SBLABELSUPP; | |
406 | ||
ddd29ec6 DQ |
407 | /* Special handling for sysfs. Is genfs but also has setxattr handler*/ |
408 | if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0) | |
409 | sbsec->flags |= SE_SBLABELSUPP; | |
410 | ||
c9180a57 EP |
411 | /* Initialize the root inode. */ |
412 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 413 | |
c9180a57 EP |
414 | /* Initialize any other inodes associated with the superblock, e.g. |
415 | inodes created prior to initial policy load or inodes created | |
416 | during get_sb by a pseudo filesystem that directly | |
417 | populates itself. */ | |
418 | spin_lock(&sbsec->isec_lock); | |
419 | next_inode: | |
420 | if (!list_empty(&sbsec->isec_head)) { | |
421 | struct inode_security_struct *isec = | |
422 | list_entry(sbsec->isec_head.next, | |
423 | struct inode_security_struct, list); | |
424 | struct inode *inode = isec->inode; | |
425 | spin_unlock(&sbsec->isec_lock); | |
426 | inode = igrab(inode); | |
427 | if (inode) { | |
428 | if (!IS_PRIVATE(inode)) | |
429 | inode_doinit(inode); | |
430 | iput(inode); | |
431 | } | |
432 | spin_lock(&sbsec->isec_lock); | |
433 | list_del_init(&isec->list); | |
434 | goto next_inode; | |
435 | } | |
436 | spin_unlock(&sbsec->isec_lock); | |
437 | out: | |
438 | return rc; | |
439 | } | |
1da177e4 | 440 | |
c9180a57 EP |
441 | /* |
442 | * This function should allow an FS to ask what it's mount security | |
443 | * options were so it can use those later for submounts, displaying | |
444 | * mount options, or whatever. | |
445 | */ | |
446 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
e0007529 | 447 | struct security_mnt_opts *opts) |
c9180a57 EP |
448 | { |
449 | int rc = 0, i; | |
450 | struct superblock_security_struct *sbsec = sb->s_security; | |
451 | char *context = NULL; | |
452 | u32 len; | |
453 | char tmp; | |
1da177e4 | 454 | |
e0007529 | 455 | security_init_mnt_opts(opts); |
1da177e4 | 456 | |
0d90a7ec | 457 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
c9180a57 | 458 | return -EINVAL; |
1da177e4 | 459 | |
c9180a57 EP |
460 | if (!ss_initialized) |
461 | return -EINVAL; | |
1da177e4 | 462 | |
0d90a7ec | 463 | tmp = sbsec->flags & SE_MNTMASK; |
c9180a57 EP |
464 | /* count the number of mount options for this sb */ |
465 | for (i = 0; i < 8; i++) { | |
466 | if (tmp & 0x01) | |
e0007529 | 467 | opts->num_mnt_opts++; |
c9180a57 EP |
468 | tmp >>= 1; |
469 | } | |
11689d47 DQ |
470 | /* Check if the Label support flag is set */ |
471 | if (sbsec->flags & SE_SBLABELSUPP) | |
472 | opts->num_mnt_opts++; | |
1da177e4 | 473 | |
e0007529 EP |
474 | opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); |
475 | if (!opts->mnt_opts) { | |
c9180a57 EP |
476 | rc = -ENOMEM; |
477 | goto out_free; | |
478 | } | |
1da177e4 | 479 | |
e0007529 EP |
480 | opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); |
481 | if (!opts->mnt_opts_flags) { | |
c9180a57 EP |
482 | rc = -ENOMEM; |
483 | goto out_free; | |
484 | } | |
1da177e4 | 485 | |
c9180a57 EP |
486 | i = 0; |
487 | if (sbsec->flags & FSCONTEXT_MNT) { | |
488 | rc = security_sid_to_context(sbsec->sid, &context, &len); | |
489 | if (rc) | |
490 | goto out_free; | |
e0007529 EP |
491 | opts->mnt_opts[i] = context; |
492 | opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; | |
c9180a57 EP |
493 | } |
494 | if (sbsec->flags & CONTEXT_MNT) { | |
495 | rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); | |
496 | if (rc) | |
497 | goto out_free; | |
e0007529 EP |
498 | opts->mnt_opts[i] = context; |
499 | opts->mnt_opts_flags[i++] = CONTEXT_MNT; | |
c9180a57 EP |
500 | } |
501 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
502 | rc = security_sid_to_context(sbsec->def_sid, &context, &len); | |
503 | if (rc) | |
504 | goto out_free; | |
e0007529 EP |
505 | opts->mnt_opts[i] = context; |
506 | opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
507 | } |
508 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
509 | struct inode *root = sbsec->sb->s_root->d_inode; | |
510 | struct inode_security_struct *isec = root->i_security; | |
0808925e | 511 | |
c9180a57 EP |
512 | rc = security_sid_to_context(isec->sid, &context, &len); |
513 | if (rc) | |
514 | goto out_free; | |
e0007529 EP |
515 | opts->mnt_opts[i] = context; |
516 | opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; | |
c9180a57 | 517 | } |
11689d47 DQ |
518 | if (sbsec->flags & SE_SBLABELSUPP) { |
519 | opts->mnt_opts[i] = NULL; | |
520 | opts->mnt_opts_flags[i++] = SE_SBLABELSUPP; | |
521 | } | |
1da177e4 | 522 | |
e0007529 | 523 | BUG_ON(i != opts->num_mnt_opts); |
1da177e4 | 524 | |
c9180a57 EP |
525 | return 0; |
526 | ||
527 | out_free: | |
e0007529 | 528 | security_free_mnt_opts(opts); |
c9180a57 EP |
529 | return rc; |
530 | } | |
1da177e4 | 531 | |
c9180a57 EP |
532 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
533 | u32 old_sid, u32 new_sid) | |
534 | { | |
0d90a7ec DQ |
535 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
536 | ||
c9180a57 | 537 | /* check if the old mount command had the same options */ |
0d90a7ec | 538 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
539 | if (!(sbsec->flags & flag) || |
540 | (old_sid != new_sid)) | |
541 | return 1; | |
542 | ||
543 | /* check if we were passed the same options twice, | |
544 | * aka someone passed context=a,context=b | |
545 | */ | |
0d90a7ec DQ |
546 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
547 | if (mnt_flags & flag) | |
c9180a57 EP |
548 | return 1; |
549 | return 0; | |
550 | } | |
e0007529 | 551 | |
c9180a57 EP |
552 | /* |
553 | * Allow filesystems with binary mount data to explicitly set mount point | |
554 | * labeling information. | |
555 | */ | |
e0007529 | 556 | static int selinux_set_mnt_opts(struct super_block *sb, |
649f6e77 DQ |
557 | struct security_mnt_opts *opts, |
558 | unsigned long kern_flags, | |
559 | unsigned long *set_kern_flags) | |
c9180a57 | 560 | { |
275bb41e | 561 | const struct cred *cred = current_cred(); |
c9180a57 | 562 | int rc = 0, i; |
c9180a57 EP |
563 | struct superblock_security_struct *sbsec = sb->s_security; |
564 | const char *name = sb->s_type->name; | |
089be43e JM |
565 | struct inode *inode = sbsec->sb->s_root->d_inode; |
566 | struct inode_security_struct *root_isec = inode->i_security; | |
c9180a57 EP |
567 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
568 | u32 defcontext_sid = 0; | |
e0007529 EP |
569 | char **mount_options = opts->mnt_opts; |
570 | int *flags = opts->mnt_opts_flags; | |
571 | int num_opts = opts->num_mnt_opts; | |
c9180a57 EP |
572 | |
573 | mutex_lock(&sbsec->lock); | |
574 | ||
575 | if (!ss_initialized) { | |
576 | if (!num_opts) { | |
577 | /* Defer initialization until selinux_complete_init, | |
578 | after the initial policy is loaded and the security | |
579 | server is ready to handle calls. */ | |
c9180a57 EP |
580 | goto out; |
581 | } | |
582 | rc = -EINVAL; | |
744ba35e EP |
583 | printk(KERN_WARNING "SELinux: Unable to set superblock options " |
584 | "before the security server is initialized\n"); | |
1da177e4 | 585 | goto out; |
c9180a57 | 586 | } |
649f6e77 DQ |
587 | if (kern_flags && !set_kern_flags) { |
588 | /* Specifying internal flags without providing a place to | |
589 | * place the results is not allowed */ | |
590 | rc = -EINVAL; | |
591 | goto out; | |
592 | } | |
1da177e4 | 593 | |
e0007529 EP |
594 | /* |
595 | * Binary mount data FS will come through this function twice. Once | |
596 | * from an explicit call and once from the generic calls from the vfs. | |
597 | * Since the generic VFS calls will not contain any security mount data | |
598 | * we need to skip the double mount verification. | |
599 | * | |
600 | * This does open a hole in which we will not notice if the first | |
601 | * mount using this sb set explict options and a second mount using | |
602 | * this sb does not set any security options. (The first options | |
603 | * will be used for both mounts) | |
604 | */ | |
0d90a7ec | 605 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
e0007529 | 606 | && (num_opts == 0)) |
f5269710 | 607 | goto out; |
e0007529 | 608 | |
c9180a57 EP |
609 | /* |
610 | * parse the mount options, check if they are valid sids. | |
611 | * also check if someone is trying to mount the same sb more | |
612 | * than once with different security options. | |
613 | */ | |
614 | for (i = 0; i < num_opts; i++) { | |
615 | u32 sid; | |
11689d47 DQ |
616 | |
617 | if (flags[i] == SE_SBLABELSUPP) | |
618 | continue; | |
c9180a57 EP |
619 | rc = security_context_to_sid(mount_options[i], |
620 | strlen(mount_options[i]), &sid); | |
1da177e4 LT |
621 | if (rc) { |
622 | printk(KERN_WARNING "SELinux: security_context_to_sid" | |
623 | "(%s) failed for (dev %s, type %s) errno=%d\n", | |
c9180a57 EP |
624 | mount_options[i], sb->s_id, name, rc); |
625 | goto out; | |
626 | } | |
627 | switch (flags[i]) { | |
628 | case FSCONTEXT_MNT: | |
629 | fscontext_sid = sid; | |
630 | ||
631 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
632 | fscontext_sid)) | |
633 | goto out_double_mount; | |
634 | ||
635 | sbsec->flags |= FSCONTEXT_MNT; | |
636 | break; | |
637 | case CONTEXT_MNT: | |
638 | context_sid = sid; | |
639 | ||
640 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
641 | context_sid)) | |
642 | goto out_double_mount; | |
643 | ||
644 | sbsec->flags |= CONTEXT_MNT; | |
645 | break; | |
646 | case ROOTCONTEXT_MNT: | |
647 | rootcontext_sid = sid; | |
648 | ||
649 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
650 | rootcontext_sid)) | |
651 | goto out_double_mount; | |
652 | ||
653 | sbsec->flags |= ROOTCONTEXT_MNT; | |
654 | ||
655 | break; | |
656 | case DEFCONTEXT_MNT: | |
657 | defcontext_sid = sid; | |
658 | ||
659 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
660 | defcontext_sid)) | |
661 | goto out_double_mount; | |
662 | ||
663 | sbsec->flags |= DEFCONTEXT_MNT; | |
664 | ||
665 | break; | |
666 | default: | |
667 | rc = -EINVAL; | |
668 | goto out; | |
1da177e4 | 669 | } |
c9180a57 EP |
670 | } |
671 | ||
0d90a7ec | 672 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 673 | /* previously mounted with options, but not on this attempt? */ |
0d90a7ec | 674 | if ((sbsec->flags & SE_MNTMASK) && !num_opts) |
c9180a57 EP |
675 | goto out_double_mount; |
676 | rc = 0; | |
677 | goto out; | |
678 | } | |
679 | ||
089be43e | 680 | if (strcmp(sb->s_type->name, "proc") == 0) |
0d90a7ec | 681 | sbsec->flags |= SE_SBPROC; |
c9180a57 | 682 | |
eb9ae686 DQ |
683 | if (!sbsec->behavior) { |
684 | /* | |
685 | * Determine the labeling behavior to use for this | |
686 | * filesystem type. | |
687 | */ | |
688 | rc = security_fs_use((sbsec->flags & SE_SBPROC) ? | |
689 | "proc" : sb->s_type->name, | |
690 | &sbsec->behavior, &sbsec->sid); | |
691 | if (rc) { | |
692 | printk(KERN_WARNING | |
693 | "%s: security_fs_use(%s) returned %d\n", | |
694 | __func__, sb->s_type->name, rc); | |
695 | goto out; | |
696 | } | |
c9180a57 | 697 | } |
c9180a57 EP |
698 | /* sets the context of the superblock for the fs being mounted. */ |
699 | if (fscontext_sid) { | |
275bb41e | 700 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
1da177e4 | 701 | if (rc) |
c9180a57 | 702 | goto out; |
1da177e4 | 703 | |
c9180a57 | 704 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
705 | } |
706 | ||
707 | /* | |
708 | * Switch to using mount point labeling behavior. | |
709 | * sets the label used on all file below the mountpoint, and will set | |
710 | * the superblock context if not already set. | |
711 | */ | |
eb9ae686 DQ |
712 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { |
713 | sbsec->behavior = SECURITY_FS_USE_NATIVE; | |
714 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
715 | } | |
716 | ||
c9180a57 EP |
717 | if (context_sid) { |
718 | if (!fscontext_sid) { | |
275bb41e DH |
719 | rc = may_context_mount_sb_relabel(context_sid, sbsec, |
720 | cred); | |
b04ea3ce | 721 | if (rc) |
c9180a57 EP |
722 | goto out; |
723 | sbsec->sid = context_sid; | |
b04ea3ce | 724 | } else { |
275bb41e DH |
725 | rc = may_context_mount_inode_relabel(context_sid, sbsec, |
726 | cred); | |
b04ea3ce | 727 | if (rc) |
c9180a57 | 728 | goto out; |
b04ea3ce | 729 | } |
c9180a57 EP |
730 | if (!rootcontext_sid) |
731 | rootcontext_sid = context_sid; | |
1da177e4 | 732 | |
c9180a57 | 733 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 734 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
735 | } |
736 | ||
c9180a57 | 737 | if (rootcontext_sid) { |
275bb41e DH |
738 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
739 | cred); | |
0808925e | 740 | if (rc) |
c9180a57 | 741 | goto out; |
0808925e | 742 | |
c9180a57 EP |
743 | root_isec->sid = rootcontext_sid; |
744 | root_isec->initialized = 1; | |
0808925e EP |
745 | } |
746 | ||
c9180a57 | 747 | if (defcontext_sid) { |
eb9ae686 DQ |
748 | if (sbsec->behavior != SECURITY_FS_USE_XATTR && |
749 | sbsec->behavior != SECURITY_FS_USE_NATIVE) { | |
c9180a57 EP |
750 | rc = -EINVAL; |
751 | printk(KERN_WARNING "SELinux: defcontext option is " | |
752 | "invalid for this filesystem type\n"); | |
753 | goto out; | |
1da177e4 LT |
754 | } |
755 | ||
c9180a57 EP |
756 | if (defcontext_sid != sbsec->def_sid) { |
757 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
275bb41e | 758 | sbsec, cred); |
c9180a57 EP |
759 | if (rc) |
760 | goto out; | |
761 | } | |
1da177e4 | 762 | |
c9180a57 | 763 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
764 | } |
765 | ||
c9180a57 | 766 | rc = sb_finish_set_opts(sb); |
1da177e4 | 767 | out: |
c9180a57 | 768 | mutex_unlock(&sbsec->lock); |
1da177e4 | 769 | return rc; |
c9180a57 EP |
770 | out_double_mount: |
771 | rc = -EINVAL; | |
772 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " | |
773 | "security settings for (dev %s, type %s)\n", sb->s_id, name); | |
774 | goto out; | |
1da177e4 LT |
775 | } |
776 | ||
094f7b69 JL |
777 | static int selinux_cmp_sb_context(const struct super_block *oldsb, |
778 | const struct super_block *newsb) | |
779 | { | |
780 | struct superblock_security_struct *old = oldsb->s_security; | |
781 | struct superblock_security_struct *new = newsb->s_security; | |
782 | char oldflags = old->flags & SE_MNTMASK; | |
783 | char newflags = new->flags & SE_MNTMASK; | |
784 | ||
785 | if (oldflags != newflags) | |
786 | goto mismatch; | |
787 | if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) | |
788 | goto mismatch; | |
789 | if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) | |
790 | goto mismatch; | |
791 | if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) | |
792 | goto mismatch; | |
793 | if (oldflags & ROOTCONTEXT_MNT) { | |
794 | struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security; | |
795 | struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security; | |
796 | if (oldroot->sid != newroot->sid) | |
797 | goto mismatch; | |
798 | } | |
799 | return 0; | |
800 | mismatch: | |
801 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " | |
802 | "different security settings for (dev %s, " | |
803 | "type %s)\n", newsb->s_id, newsb->s_type->name); | |
804 | return -EBUSY; | |
805 | } | |
806 | ||
807 | static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, | |
c9180a57 | 808 | struct super_block *newsb) |
1da177e4 | 809 | { |
c9180a57 EP |
810 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
811 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 812 | |
c9180a57 EP |
813 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
814 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
815 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 816 | |
0f5e6420 EP |
817 | /* |
818 | * if the parent was able to be mounted it clearly had no special lsm | |
e8c26255 | 819 | * mount options. thus we can safely deal with this superblock later |
0f5e6420 | 820 | */ |
e8c26255 | 821 | if (!ss_initialized) |
094f7b69 | 822 | return 0; |
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 | |
094f7b69 | 827 | /* if fs is reusing a sb, make sure that the contexts match */ |
0d90a7ec | 828 | if (newsbsec->flags & SE_SBINITIALIZED) |
094f7b69 | 829 | return selinux_cmp_sb_context(oldsb, newsb); |
5a552617 | 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); | |
094f7b69 | 862 | return 0; |
c9180a57 EP |
863 | } |
864 | ||
2e1479d9 AB |
865 | static int selinux_parse_opts_str(char *options, |
866 | struct security_mnt_opts *opts) | |
c9180a57 | 867 | { |
e0007529 | 868 | char *p; |
c9180a57 EP |
869 | char *context = NULL, *defcontext = NULL; |
870 | char *fscontext = NULL, *rootcontext = NULL; | |
e0007529 | 871 | int rc, num_mnt_opts = 0; |
1da177e4 | 872 | |
e0007529 | 873 | opts->num_mnt_opts = 0; |
1da177e4 | 874 | |
c9180a57 EP |
875 | /* Standard string-based options. */ |
876 | while ((p = strsep(&options, "|")) != NULL) { | |
877 | int token; | |
878 | substring_t args[MAX_OPT_ARGS]; | |
1da177e4 | 879 | |
c9180a57 EP |
880 | if (!*p) |
881 | continue; | |
1da177e4 | 882 | |
c9180a57 | 883 | token = match_token(p, tokens, args); |
1da177e4 | 884 | |
c9180a57 EP |
885 | switch (token) { |
886 | case Opt_context: | |
887 | if (context || defcontext) { | |
888 | rc = -EINVAL; | |
889 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
890 | goto out_err; | |
891 | } | |
892 | context = match_strdup(&args[0]); | |
893 | if (!context) { | |
894 | rc = -ENOMEM; | |
895 | goto out_err; | |
896 | } | |
897 | break; | |
898 | ||
899 | case Opt_fscontext: | |
900 | if (fscontext) { | |
901 | rc = -EINVAL; | |
902 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
903 | goto out_err; | |
904 | } | |
905 | fscontext = match_strdup(&args[0]); | |
906 | if (!fscontext) { | |
907 | rc = -ENOMEM; | |
908 | goto out_err; | |
909 | } | |
910 | break; | |
911 | ||
912 | case Opt_rootcontext: | |
913 | if (rootcontext) { | |
914 | rc = -EINVAL; | |
915 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
916 | goto out_err; | |
917 | } | |
918 | rootcontext = match_strdup(&args[0]); | |
919 | if (!rootcontext) { | |
920 | rc = -ENOMEM; | |
921 | goto out_err; | |
922 | } | |
923 | break; | |
924 | ||
925 | case Opt_defcontext: | |
926 | if (context || defcontext) { | |
927 | rc = -EINVAL; | |
928 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
929 | goto out_err; | |
930 | } | |
931 | defcontext = match_strdup(&args[0]); | |
932 | if (!defcontext) { | |
933 | rc = -ENOMEM; | |
934 | goto out_err; | |
935 | } | |
936 | break; | |
11689d47 DQ |
937 | case Opt_labelsupport: |
938 | break; | |
c9180a57 EP |
939 | default: |
940 | rc = -EINVAL; | |
941 | printk(KERN_WARNING "SELinux: unknown mount option\n"); | |
942 | goto out_err; | |
1da177e4 | 943 | |
1da177e4 | 944 | } |
1da177e4 | 945 | } |
c9180a57 | 946 | |
e0007529 EP |
947 | rc = -ENOMEM; |
948 | opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); | |
949 | if (!opts->mnt_opts) | |
950 | goto out_err; | |
951 | ||
952 | opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); | |
953 | if (!opts->mnt_opts_flags) { | |
954 | kfree(opts->mnt_opts); | |
955 | goto out_err; | |
956 | } | |
957 | ||
c9180a57 | 958 | if (fscontext) { |
e0007529 EP |
959 | opts->mnt_opts[num_mnt_opts] = fscontext; |
960 | opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; | |
c9180a57 EP |
961 | } |
962 | if (context) { | |
e0007529 EP |
963 | opts->mnt_opts[num_mnt_opts] = context; |
964 | opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; | |
c9180a57 EP |
965 | } |
966 | if (rootcontext) { | |
e0007529 EP |
967 | opts->mnt_opts[num_mnt_opts] = rootcontext; |
968 | opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; | |
c9180a57 EP |
969 | } |
970 | if (defcontext) { | |
e0007529 EP |
971 | opts->mnt_opts[num_mnt_opts] = defcontext; |
972 | opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
973 | } |
974 | ||
e0007529 EP |
975 | opts->num_mnt_opts = num_mnt_opts; |
976 | return 0; | |
977 | ||
c9180a57 EP |
978 | out_err: |
979 | kfree(context); | |
980 | kfree(defcontext); | |
981 | kfree(fscontext); | |
982 | kfree(rootcontext); | |
1da177e4 LT |
983 | return rc; |
984 | } | |
e0007529 EP |
985 | /* |
986 | * string mount options parsing and call set the sbsec | |
987 | */ | |
988 | static int superblock_doinit(struct super_block *sb, void *data) | |
989 | { | |
990 | int rc = 0; | |
991 | char *options = data; | |
992 | struct security_mnt_opts opts; | |
993 | ||
994 | security_init_mnt_opts(&opts); | |
995 | ||
996 | if (!data) | |
997 | goto out; | |
998 | ||
999 | BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); | |
1000 | ||
1001 | rc = selinux_parse_opts_str(options, &opts); | |
1002 | if (rc) | |
1003 | goto out_err; | |
1004 | ||
1005 | out: | |
649f6e77 | 1006 | rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); |
e0007529 EP |
1007 | |
1008 | out_err: | |
1009 | security_free_mnt_opts(&opts); | |
1010 | return rc; | |
1011 | } | |
1da177e4 | 1012 | |
3583a711 AB |
1013 | static void selinux_write_opts(struct seq_file *m, |
1014 | struct security_mnt_opts *opts) | |
2069f457 EP |
1015 | { |
1016 | int i; | |
1017 | char *prefix; | |
1018 | ||
1019 | for (i = 0; i < opts->num_mnt_opts; i++) { | |
11689d47 DQ |
1020 | char *has_comma; |
1021 | ||
1022 | if (opts->mnt_opts[i]) | |
1023 | has_comma = strchr(opts->mnt_opts[i], ','); | |
1024 | else | |
1025 | has_comma = NULL; | |
2069f457 EP |
1026 | |
1027 | switch (opts->mnt_opts_flags[i]) { | |
1028 | case CONTEXT_MNT: | |
1029 | prefix = CONTEXT_STR; | |
1030 | break; | |
1031 | case FSCONTEXT_MNT: | |
1032 | prefix = FSCONTEXT_STR; | |
1033 | break; | |
1034 | case ROOTCONTEXT_MNT: | |
1035 | prefix = ROOTCONTEXT_STR; | |
1036 | break; | |
1037 | case DEFCONTEXT_MNT: | |
1038 | prefix = DEFCONTEXT_STR; | |
1039 | break; | |
11689d47 DQ |
1040 | case SE_SBLABELSUPP: |
1041 | seq_putc(m, ','); | |
1042 | seq_puts(m, LABELSUPP_STR); | |
1043 | continue; | |
2069f457 EP |
1044 | default: |
1045 | BUG(); | |
a35c6c83 | 1046 | return; |
2069f457 EP |
1047 | }; |
1048 | /* we need a comma before each option */ | |
1049 | seq_putc(m, ','); | |
1050 | seq_puts(m, prefix); | |
1051 | if (has_comma) | |
1052 | seq_putc(m, '\"'); | |
1053 | seq_puts(m, opts->mnt_opts[i]); | |
1054 | if (has_comma) | |
1055 | seq_putc(m, '\"'); | |
1056 | } | |
1057 | } | |
1058 | ||
1059 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1060 | { | |
1061 | struct security_mnt_opts opts; | |
1062 | int rc; | |
1063 | ||
1064 | rc = selinux_get_mnt_opts(sb, &opts); | |
383795c2 EP |
1065 | if (rc) { |
1066 | /* before policy load we may get EINVAL, don't show anything */ | |
1067 | if (rc == -EINVAL) | |
1068 | rc = 0; | |
2069f457 | 1069 | return rc; |
383795c2 | 1070 | } |
2069f457 EP |
1071 | |
1072 | selinux_write_opts(m, &opts); | |
1073 | ||
1074 | security_free_mnt_opts(&opts); | |
1075 | ||
1076 | return rc; | |
1077 | } | |
1078 | ||
1da177e4 LT |
1079 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1080 | { | |
1081 | switch (mode & S_IFMT) { | |
1082 | case S_IFSOCK: | |
1083 | return SECCLASS_SOCK_FILE; | |
1084 | case S_IFLNK: | |
1085 | return SECCLASS_LNK_FILE; | |
1086 | case S_IFREG: | |
1087 | return SECCLASS_FILE; | |
1088 | case S_IFBLK: | |
1089 | return SECCLASS_BLK_FILE; | |
1090 | case S_IFDIR: | |
1091 | return SECCLASS_DIR; | |
1092 | case S_IFCHR: | |
1093 | return SECCLASS_CHR_FILE; | |
1094 | case S_IFIFO: | |
1095 | return SECCLASS_FIFO_FILE; | |
1096 | ||
1097 | } | |
1098 | ||
1099 | return SECCLASS_FILE; | |
1100 | } | |
1101 | ||
13402580 JM |
1102 | static inline int default_protocol_stream(int protocol) |
1103 | { | |
1104 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1105 | } | |
1106 | ||
1107 | static inline int default_protocol_dgram(int protocol) | |
1108 | { | |
1109 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1110 | } | |
1111 | ||
1da177e4 LT |
1112 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1113 | { | |
1114 | switch (family) { | |
1115 | case PF_UNIX: | |
1116 | switch (type) { | |
1117 | case SOCK_STREAM: | |
1118 | case SOCK_SEQPACKET: | |
1119 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1120 | case SOCK_DGRAM: | |
1121 | return SECCLASS_UNIX_DGRAM_SOCKET; | |
1122 | } | |
1123 | break; | |
1124 | case PF_INET: | |
1125 | case PF_INET6: | |
1126 | switch (type) { | |
1127 | case SOCK_STREAM: | |
13402580 JM |
1128 | if (default_protocol_stream(protocol)) |
1129 | return SECCLASS_TCP_SOCKET; | |
1130 | else | |
1131 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1132 | case SOCK_DGRAM: |
13402580 JM |
1133 | if (default_protocol_dgram(protocol)) |
1134 | return SECCLASS_UDP_SOCKET; | |
1135 | else | |
1136 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1137 | case SOCK_DCCP: |
1138 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1139 | default: |
1da177e4 LT |
1140 | return SECCLASS_RAWIP_SOCKET; |
1141 | } | |
1142 | break; | |
1143 | case PF_NETLINK: | |
1144 | switch (protocol) { | |
1145 | case NETLINK_ROUTE: | |
1146 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
1147 | case NETLINK_FIREWALL: | |
1148 | return SECCLASS_NETLINK_FIREWALL_SOCKET; | |
7f1fb60c | 1149 | case NETLINK_SOCK_DIAG: |
1da177e4 LT |
1150 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1151 | case NETLINK_NFLOG: | |
1152 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1153 | case NETLINK_XFRM: | |
1154 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1155 | case NETLINK_SELINUX: | |
1156 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
1157 | case NETLINK_AUDIT: | |
1158 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
1159 | case NETLINK_IP6_FW: | |
1160 | return SECCLASS_NETLINK_IP6FW_SOCKET; | |
1161 | case NETLINK_DNRTMSG: | |
1162 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1163 | case NETLINK_KOBJECT_UEVENT: |
1164 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
1da177e4 LT |
1165 | default: |
1166 | return SECCLASS_NETLINK_SOCKET; | |
1167 | } | |
1168 | case PF_PACKET: | |
1169 | return SECCLASS_PACKET_SOCKET; | |
1170 | case PF_KEY: | |
1171 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1172 | case PF_APPLETALK: |
1173 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1174 | } |
1175 | ||
1176 | return SECCLASS_SOCKET; | |
1177 | } | |
1178 | ||
1179 | #ifdef CONFIG_PROC_FS | |
8e6c9693 | 1180 | static int selinux_proc_get_sid(struct dentry *dentry, |
1da177e4 LT |
1181 | u16 tclass, |
1182 | u32 *sid) | |
1183 | { | |
8e6c9693 LAG |
1184 | int rc; |
1185 | char *buffer, *path; | |
1da177e4 | 1186 | |
828dfe1d | 1187 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1188 | if (!buffer) |
1189 | return -ENOMEM; | |
1190 | ||
8e6c9693 LAG |
1191 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1192 | if (IS_ERR(path)) | |
1193 | rc = PTR_ERR(path); | |
1194 | else { | |
1195 | /* each process gets a /proc/PID/ entry. Strip off the | |
1196 | * PID part to get a valid selinux labeling. | |
1197 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1198 | while (path[1] >= '0' && path[1] <= '9') { | |
1199 | path[1] = '/'; | |
1200 | path++; | |
1201 | } | |
1202 | rc = security_genfs_sid("proc", path, tclass, sid); | |
1da177e4 | 1203 | } |
1da177e4 LT |
1204 | free_page((unsigned long)buffer); |
1205 | return rc; | |
1206 | } | |
1207 | #else | |
8e6c9693 | 1208 | static int selinux_proc_get_sid(struct dentry *dentry, |
1da177e4 LT |
1209 | u16 tclass, |
1210 | u32 *sid) | |
1211 | { | |
1212 | return -EINVAL; | |
1213 | } | |
1214 | #endif | |
1215 | ||
1216 | /* The inode's security attributes must be initialized before first use. */ | |
1217 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1218 | { | |
1219 | struct superblock_security_struct *sbsec = NULL; | |
1220 | struct inode_security_struct *isec = inode->i_security; | |
1221 | u32 sid; | |
1222 | struct dentry *dentry; | |
1223 | #define INITCONTEXTLEN 255 | |
1224 | char *context = NULL; | |
1225 | unsigned len = 0; | |
1226 | int rc = 0; | |
1da177e4 LT |
1227 | |
1228 | if (isec->initialized) | |
1229 | goto out; | |
1230 | ||
23970741 | 1231 | mutex_lock(&isec->lock); |
1da177e4 | 1232 | if (isec->initialized) |
23970741 | 1233 | goto out_unlock; |
1da177e4 LT |
1234 | |
1235 | sbsec = inode->i_sb->s_security; | |
0d90a7ec | 1236 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1237 | /* Defer initialization until selinux_complete_init, |
1238 | after the initial policy is loaded and the security | |
1239 | server is ready to handle calls. */ | |
1240 | spin_lock(&sbsec->isec_lock); | |
1241 | if (list_empty(&isec->list)) | |
1242 | list_add(&isec->list, &sbsec->isec_head); | |
1243 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1244 | goto out_unlock; |
1da177e4 LT |
1245 | } |
1246 | ||
1247 | switch (sbsec->behavior) { | |
eb9ae686 DQ |
1248 | case SECURITY_FS_USE_NATIVE: |
1249 | break; | |
1da177e4 LT |
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) { | |
df7f54c0 EP |
1266 | /* |
1267 | * this is can be hit on boot when a file is accessed | |
1268 | * before the policy is loaded. When we load policy we | |
1269 | * may find inodes that have no dentry on the | |
1270 | * sbsec->isec_head list. No reason to complain as these | |
1271 | * will get fixed up the next time we go through | |
1272 | * inode_doinit with a dentry, before these inodes could | |
1273 | * be used again by userspace. | |
1274 | */ | |
23970741 | 1275 | goto out_unlock; |
1da177e4 LT |
1276 | } |
1277 | ||
1278 | len = INITCONTEXTLEN; | |
4cb912f1 | 1279 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1280 | if (!context) { |
1281 | rc = -ENOMEM; | |
1282 | dput(dentry); | |
23970741 | 1283 | goto out_unlock; |
1da177e4 | 1284 | } |
4cb912f1 | 1285 | context[len] = '\0'; |
1da177e4 LT |
1286 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, |
1287 | context, len); | |
1288 | if (rc == -ERANGE) { | |
314dabb8 JM |
1289 | kfree(context); |
1290 | ||
1da177e4 LT |
1291 | /* Need a larger buffer. Query for the right size. */ |
1292 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, | |
1293 | NULL, 0); | |
1294 | if (rc < 0) { | |
1295 | dput(dentry); | |
23970741 | 1296 | goto out_unlock; |
1da177e4 | 1297 | } |
1da177e4 | 1298 | len = rc; |
4cb912f1 | 1299 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1300 | if (!context) { |
1301 | rc = -ENOMEM; | |
1302 | dput(dentry); | |
23970741 | 1303 | goto out_unlock; |
1da177e4 | 1304 | } |
4cb912f1 | 1305 | context[len] = '\0'; |
1da177e4 LT |
1306 | rc = inode->i_op->getxattr(dentry, |
1307 | XATTR_NAME_SELINUX, | |
1308 | context, len); | |
1309 | } | |
1310 | dput(dentry); | |
1311 | if (rc < 0) { | |
1312 | if (rc != -ENODATA) { | |
744ba35e | 1313 | printk(KERN_WARNING "SELinux: %s: getxattr returned " |
dd6f953a | 1314 | "%d for dev=%s ino=%ld\n", __func__, |
1da177e4 LT |
1315 | -rc, inode->i_sb->s_id, inode->i_ino); |
1316 | kfree(context); | |
23970741 | 1317 | goto out_unlock; |
1da177e4 LT |
1318 | } |
1319 | /* Map ENODATA to the default file SID */ | |
1320 | sid = sbsec->def_sid; | |
1321 | rc = 0; | |
1322 | } else { | |
f5c1d5b2 | 1323 | rc = security_context_to_sid_default(context, rc, &sid, |
869ab514 SS |
1324 | sbsec->def_sid, |
1325 | GFP_NOFS); | |
1da177e4 | 1326 | if (rc) { |
4ba0a8ad EP |
1327 | char *dev = inode->i_sb->s_id; |
1328 | unsigned long ino = inode->i_ino; | |
1329 | ||
1330 | if (rc == -EINVAL) { | |
1331 | if (printk_ratelimit()) | |
1332 | printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " | |
1333 | "context=%s. This indicates you may need to relabel the inode or the " | |
1334 | "filesystem in question.\n", ino, dev, context); | |
1335 | } else { | |
1336 | printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " | |
1337 | "returned %d for dev=%s ino=%ld\n", | |
1338 | __func__, context, -rc, dev, ino); | |
1339 | } | |
1da177e4 LT |
1340 | kfree(context); |
1341 | /* Leave with the unlabeled SID */ | |
1342 | rc = 0; | |
1343 | break; | |
1344 | } | |
1345 | } | |
1346 | kfree(context); | |
1347 | isec->sid = sid; | |
1348 | break; | |
1349 | case SECURITY_FS_USE_TASK: | |
1350 | isec->sid = isec->task_sid; | |
1351 | break; | |
1352 | case SECURITY_FS_USE_TRANS: | |
1353 | /* Default to the fs SID. */ | |
1354 | isec->sid = sbsec->sid; | |
1355 | ||
1356 | /* Try to obtain a transition SID. */ | |
1357 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
652bb9b0 EP |
1358 | rc = security_transition_sid(isec->task_sid, sbsec->sid, |
1359 | isec->sclass, NULL, &sid); | |
1da177e4 | 1360 | if (rc) |
23970741 | 1361 | goto out_unlock; |
1da177e4 LT |
1362 | isec->sid = sid; |
1363 | break; | |
c312feb2 EP |
1364 | case SECURITY_FS_USE_MNTPOINT: |
1365 | isec->sid = sbsec->mntpoint_sid; | |
1366 | break; | |
1da177e4 | 1367 | default: |
c312feb2 | 1368 | /* Default to the fs superblock SID. */ |
1da177e4 LT |
1369 | isec->sid = sbsec->sid; |
1370 | ||
0d90a7ec | 1371 | if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { |
8e6c9693 | 1372 | if (opt_dentry) { |
1da177e4 | 1373 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
8e6c9693 | 1374 | rc = selinux_proc_get_sid(opt_dentry, |
1da177e4 LT |
1375 | isec->sclass, |
1376 | &sid); | |
1377 | if (rc) | |
23970741 | 1378 | goto out_unlock; |
1da177e4 LT |
1379 | isec->sid = sid; |
1380 | } | |
1381 | } | |
1382 | break; | |
1383 | } | |
1384 | ||
1385 | isec->initialized = 1; | |
1386 | ||
23970741 EP |
1387 | out_unlock: |
1388 | mutex_unlock(&isec->lock); | |
1da177e4 LT |
1389 | out: |
1390 | if (isec->sclass == SECCLASS_FILE) | |
1391 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1da177e4 LT |
1392 | return rc; |
1393 | } | |
1394 | ||
1395 | /* Convert a Linux signal to an access vector. */ | |
1396 | static inline u32 signal_to_av(int sig) | |
1397 | { | |
1398 | u32 perm = 0; | |
1399 | ||
1400 | switch (sig) { | |
1401 | case SIGCHLD: | |
1402 | /* Commonly granted from child to parent. */ | |
1403 | perm = PROCESS__SIGCHLD; | |
1404 | break; | |
1405 | case SIGKILL: | |
1406 | /* Cannot be caught or ignored */ | |
1407 | perm = PROCESS__SIGKILL; | |
1408 | break; | |
1409 | case SIGSTOP: | |
1410 | /* Cannot be caught or ignored */ | |
1411 | perm = PROCESS__SIGSTOP; | |
1412 | break; | |
1413 | default: | |
1414 | /* All other signals. */ | |
1415 | perm = PROCESS__SIGNAL; | |
1416 | break; | |
1417 | } | |
1418 | ||
1419 | return perm; | |
1420 | } | |
1421 | ||
d84f4f99 DH |
1422 | /* |
1423 | * Check permission between a pair of credentials | |
1424 | * fork check, ptrace check, etc. | |
1425 | */ | |
1426 | static int cred_has_perm(const struct cred *actor, | |
1427 | const struct cred *target, | |
1428 | u32 perms) | |
1429 | { | |
1430 | u32 asid = cred_sid(actor), tsid = cred_sid(target); | |
1431 | ||
1432 | return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); | |
1433 | } | |
1434 | ||
275bb41e | 1435 | /* |
88e67f3b | 1436 | * Check permission between a pair of tasks, e.g. signal checks, |
275bb41e DH |
1437 | * fork check, ptrace check, etc. |
1438 | * tsk1 is the actor and tsk2 is the target | |
3b11a1de | 1439 | * - this uses the default subjective creds of tsk1 |
275bb41e DH |
1440 | */ |
1441 | static int task_has_perm(const struct task_struct *tsk1, | |
1442 | const struct task_struct *tsk2, | |
1da177e4 LT |
1443 | u32 perms) |
1444 | { | |
275bb41e DH |
1445 | const struct task_security_struct *__tsec1, *__tsec2; |
1446 | u32 sid1, sid2; | |
1da177e4 | 1447 | |
275bb41e DH |
1448 | rcu_read_lock(); |
1449 | __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; | |
1450 | __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; | |
1451 | rcu_read_unlock(); | |
1452 | return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); | |
1da177e4 LT |
1453 | } |
1454 | ||
3b11a1de DH |
1455 | /* |
1456 | * Check permission between current and another task, e.g. signal checks, | |
1457 | * fork check, ptrace check, etc. | |
1458 | * current is the actor and tsk2 is the target | |
1459 | * - this uses current's subjective creds | |
1460 | */ | |
1461 | static int current_has_perm(const struct task_struct *tsk, | |
1462 | u32 perms) | |
1463 | { | |
1464 | u32 sid, tsid; | |
1465 | ||
1466 | sid = current_sid(); | |
1467 | tsid = task_sid(tsk); | |
1468 | return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); | |
1469 | } | |
1470 | ||
b68e418c SS |
1471 | #if CAP_LAST_CAP > 63 |
1472 | #error Fix SELinux to handle capabilities > 63. | |
1473 | #endif | |
1474 | ||
1da177e4 | 1475 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1476 | static int cred_has_capability(const struct cred *cred, |
06112163 | 1477 | int cap, int audit) |
1da177e4 | 1478 | { |
2bf49690 | 1479 | struct common_audit_data ad; |
06112163 | 1480 | struct av_decision avd; |
b68e418c | 1481 | u16 sclass; |
3699c53c | 1482 | u32 sid = cred_sid(cred); |
b68e418c | 1483 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1484 | int rc; |
1da177e4 | 1485 | |
50c205f5 | 1486 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1487 | ad.u.cap = cap; |
1488 | ||
b68e418c SS |
1489 | switch (CAP_TO_INDEX(cap)) { |
1490 | case 0: | |
1491 | sclass = SECCLASS_CAPABILITY; | |
1492 | break; | |
1493 | case 1: | |
1494 | sclass = SECCLASS_CAPABILITY2; | |
1495 | break; | |
1496 | default: | |
1497 | printk(KERN_ERR | |
1498 | "SELinux: out of range capability %d\n", cap); | |
1499 | BUG(); | |
a35c6c83 | 1500 | return -EINVAL; |
b68e418c | 1501 | } |
06112163 | 1502 | |
275bb41e | 1503 | rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); |
9ade0cf4 | 1504 | if (audit == SECURITY_CAP_AUDIT) { |
ab354062 | 1505 | int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); |
9ade0cf4 EP |
1506 | if (rc2) |
1507 | return rc2; | |
1508 | } | |
06112163 | 1509 | return rc; |
1da177e4 LT |
1510 | } |
1511 | ||
1512 | /* Check whether a task is allowed to use a system operation. */ | |
1513 | static int task_has_system(struct task_struct *tsk, | |
1514 | u32 perms) | |
1515 | { | |
275bb41e | 1516 | u32 sid = task_sid(tsk); |
1da177e4 | 1517 | |
275bb41e | 1518 | return avc_has_perm(sid, SECINITSID_KERNEL, |
1da177e4 LT |
1519 | SECCLASS_SYSTEM, perms, NULL); |
1520 | } | |
1521 | ||
1522 | /* Check whether a task has a particular permission to an inode. | |
1523 | The 'adp' parameter is optional and allows other audit | |
1524 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1525 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1526 | struct inode *inode, |
1527 | u32 perms, | |
19e49834 | 1528 | struct common_audit_data *adp) |
1da177e4 | 1529 | { |
1da177e4 | 1530 | struct inode_security_struct *isec; |
275bb41e | 1531 | u32 sid; |
1da177e4 | 1532 | |
e0e81739 DH |
1533 | validate_creds(cred); |
1534 | ||
828dfe1d | 1535 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1536 | return 0; |
1537 | ||
88e67f3b | 1538 | sid = cred_sid(cred); |
1da177e4 LT |
1539 | isec = inode->i_security; |
1540 | ||
19e49834 | 1541 | return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); |
1da177e4 LT |
1542 | } |
1543 | ||
1544 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1545 | the dentry to help the auditing code to more easily generate the | |
1546 | pathname if needed. */ | |
88e67f3b | 1547 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1548 | struct dentry *dentry, |
1549 | u32 av) | |
1550 | { | |
1551 | struct inode *inode = dentry->d_inode; | |
2bf49690 | 1552 | struct common_audit_data ad; |
88e67f3b | 1553 | |
50c205f5 | 1554 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1555 | ad.u.dentry = dentry; |
19e49834 | 1556 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1557 | } |
1558 | ||
1559 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1560 | the path to help the auditing code to more easily generate the | |
1561 | pathname if needed. */ | |
1562 | static inline int path_has_perm(const struct cred *cred, | |
1563 | struct path *path, | |
1564 | u32 av) | |
1565 | { | |
1566 | struct inode *inode = path->dentry->d_inode; | |
1567 | struct common_audit_data ad; | |
1568 | ||
50c205f5 | 1569 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1570 | ad.u.path = *path; |
19e49834 | 1571 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1572 | } |
1573 | ||
13f8e981 DH |
1574 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1575 | static inline int file_path_has_perm(const struct cred *cred, | |
1576 | struct file *file, | |
1577 | u32 av) | |
1578 | { | |
1579 | struct common_audit_data ad; | |
1580 | ||
1581 | ad.type = LSM_AUDIT_DATA_PATH; | |
1582 | ad.u.path = file->f_path; | |
19e49834 | 1583 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1584 | } |
1585 | ||
1da177e4 LT |
1586 | /* Check whether a task can use an open file descriptor to |
1587 | access an inode in a given way. Check access to the | |
1588 | descriptor itself, and then use dentry_has_perm to | |
1589 | check a particular permission to the file. | |
1590 | Access to the descriptor is implicitly granted if it | |
1591 | has the same SID as the process. If av is zero, then | |
1592 | access to the file is not checked, e.g. for cases | |
1593 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1594 | static int file_has_perm(const struct cred *cred, |
1595 | struct file *file, | |
1596 | u32 av) | |
1da177e4 | 1597 | { |
1da177e4 | 1598 | struct file_security_struct *fsec = file->f_security; |
496ad9aa | 1599 | struct inode *inode = file_inode(file); |
2bf49690 | 1600 | struct common_audit_data ad; |
88e67f3b | 1601 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1602 | int rc; |
1603 | ||
50c205f5 | 1604 | ad.type = LSM_AUDIT_DATA_PATH; |
f48b7399 | 1605 | ad.u.path = file->f_path; |
1da177e4 | 1606 | |
275bb41e DH |
1607 | if (sid != fsec->sid) { |
1608 | rc = avc_has_perm(sid, fsec->sid, | |
1da177e4 LT |
1609 | SECCLASS_FD, |
1610 | FD__USE, | |
1611 | &ad); | |
1612 | if (rc) | |
88e67f3b | 1613 | goto out; |
1da177e4 LT |
1614 | } |
1615 | ||
1616 | /* av is zero if only checking access to the descriptor. */ | |
88e67f3b | 1617 | rc = 0; |
1da177e4 | 1618 | if (av) |
19e49834 | 1619 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1620 | |
88e67f3b DH |
1621 | out: |
1622 | return rc; | |
1da177e4 LT |
1623 | } |
1624 | ||
1625 | /* Check whether a task can create a file. */ | |
1626 | static int may_create(struct inode *dir, | |
1627 | struct dentry *dentry, | |
1628 | u16 tclass) | |
1629 | { | |
5fb49870 | 1630 | const struct task_security_struct *tsec = current_security(); |
1da177e4 LT |
1631 | struct inode_security_struct *dsec; |
1632 | struct superblock_security_struct *sbsec; | |
275bb41e | 1633 | u32 sid, newsid; |
2bf49690 | 1634 | struct common_audit_data ad; |
1da177e4 LT |
1635 | int rc; |
1636 | ||
1da177e4 LT |
1637 | dsec = dir->i_security; |
1638 | sbsec = dir->i_sb->s_security; | |
1639 | ||
275bb41e DH |
1640 | sid = tsec->sid; |
1641 | newsid = tsec->create_sid; | |
1642 | ||
50c205f5 | 1643 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1644 | ad.u.dentry = dentry; |
1da177e4 | 1645 | |
275bb41e | 1646 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
1647 | DIR__ADD_NAME | DIR__SEARCH, |
1648 | &ad); | |
1649 | if (rc) | |
1650 | return rc; | |
1651 | ||
cd89596f | 1652 | if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { |
cb1e922f EP |
1653 | rc = security_transition_sid(sid, dsec->sid, tclass, |
1654 | &dentry->d_name, &newsid); | |
1da177e4 LT |
1655 | if (rc) |
1656 | return rc; | |
1657 | } | |
1658 | ||
275bb41e | 1659 | rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); |
1da177e4 LT |
1660 | if (rc) |
1661 | return rc; | |
1662 | ||
1663 | return avc_has_perm(newsid, sbsec->sid, | |
1664 | SECCLASS_FILESYSTEM, | |
1665 | FILESYSTEM__ASSOCIATE, &ad); | |
1666 | } | |
1667 | ||
4eb582cf ML |
1668 | /* Check whether a task can create a key. */ |
1669 | static int may_create_key(u32 ksid, | |
1670 | struct task_struct *ctx) | |
1671 | { | |
275bb41e | 1672 | u32 sid = task_sid(ctx); |
4eb582cf | 1673 | |
275bb41e | 1674 | return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); |
4eb582cf ML |
1675 | } |
1676 | ||
828dfe1d EP |
1677 | #define MAY_LINK 0 |
1678 | #define MAY_UNLINK 1 | |
1679 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1680 | |
1681 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1682 | static int may_link(struct inode *dir, | |
1683 | struct dentry *dentry, | |
1684 | int kind) | |
1685 | ||
1686 | { | |
1da177e4 | 1687 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 1688 | struct common_audit_data ad; |
275bb41e | 1689 | u32 sid = current_sid(); |
1da177e4 LT |
1690 | u32 av; |
1691 | int rc; | |
1692 | ||
1da177e4 LT |
1693 | dsec = dir->i_security; |
1694 | isec = dentry->d_inode->i_security; | |
1695 | ||
50c205f5 | 1696 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1697 | ad.u.dentry = dentry; |
1da177e4 LT |
1698 | |
1699 | av = DIR__SEARCH; | |
1700 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
275bb41e | 1701 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
1702 | if (rc) |
1703 | return rc; | |
1704 | ||
1705 | switch (kind) { | |
1706 | case MAY_LINK: | |
1707 | av = FILE__LINK; | |
1708 | break; | |
1709 | case MAY_UNLINK: | |
1710 | av = FILE__UNLINK; | |
1711 | break; | |
1712 | case MAY_RMDIR: | |
1713 | av = DIR__RMDIR; | |
1714 | break; | |
1715 | default: | |
744ba35e EP |
1716 | printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", |
1717 | __func__, kind); | |
1da177e4 LT |
1718 | return 0; |
1719 | } | |
1720 | ||
275bb41e | 1721 | rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); |
1da177e4 LT |
1722 | return rc; |
1723 | } | |
1724 | ||
1725 | static inline int may_rename(struct inode *old_dir, | |
1726 | struct dentry *old_dentry, | |
1727 | struct inode *new_dir, | |
1728 | struct dentry *new_dentry) | |
1729 | { | |
1da177e4 | 1730 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 1731 | struct common_audit_data ad; |
275bb41e | 1732 | u32 sid = current_sid(); |
1da177e4 LT |
1733 | u32 av; |
1734 | int old_is_dir, new_is_dir; | |
1735 | int rc; | |
1736 | ||
1da177e4 LT |
1737 | old_dsec = old_dir->i_security; |
1738 | old_isec = old_dentry->d_inode->i_security; | |
1739 | old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); | |
1740 | new_dsec = new_dir->i_security; | |
1741 | ||
50c205f5 | 1742 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 1743 | |
a269434d | 1744 | ad.u.dentry = old_dentry; |
275bb41e | 1745 | rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
1746 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
1747 | if (rc) | |
1748 | return rc; | |
275bb41e | 1749 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
1750 | old_isec->sclass, FILE__RENAME, &ad); |
1751 | if (rc) | |
1752 | return rc; | |
1753 | if (old_is_dir && new_dir != old_dir) { | |
275bb41e | 1754 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
1755 | old_isec->sclass, DIR__REPARENT, &ad); |
1756 | if (rc) | |
1757 | return rc; | |
1758 | } | |
1759 | ||
a269434d | 1760 | ad.u.dentry = new_dentry; |
1da177e4 LT |
1761 | av = DIR__ADD_NAME | DIR__SEARCH; |
1762 | if (new_dentry->d_inode) | |
1763 | av |= DIR__REMOVE_NAME; | |
275bb41e | 1764 | rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
1765 | if (rc) |
1766 | return rc; | |
1767 | if (new_dentry->d_inode) { | |
1768 | new_isec = new_dentry->d_inode->i_security; | |
1769 | new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); | |
275bb41e | 1770 | rc = avc_has_perm(sid, new_isec->sid, |
1da177e4 LT |
1771 | new_isec->sclass, |
1772 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1773 | if (rc) | |
1774 | return rc; | |
1775 | } | |
1776 | ||
1777 | return 0; | |
1778 | } | |
1779 | ||
1780 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 1781 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
1782 | struct super_block *sb, |
1783 | u32 perms, | |
2bf49690 | 1784 | struct common_audit_data *ad) |
1da177e4 | 1785 | { |
1da177e4 | 1786 | struct superblock_security_struct *sbsec; |
88e67f3b | 1787 | u32 sid = cred_sid(cred); |
1da177e4 | 1788 | |
1da177e4 | 1789 | sbsec = sb->s_security; |
275bb41e | 1790 | return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); |
1da177e4 LT |
1791 | } |
1792 | ||
1793 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1794 | static inline u32 file_mask_to_av(int mode, int mask) | |
1795 | { | |
1796 | u32 av = 0; | |
1797 | ||
dba19c60 | 1798 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
1799 | if (mask & MAY_EXEC) |
1800 | av |= FILE__EXECUTE; | |
1801 | if (mask & MAY_READ) | |
1802 | av |= FILE__READ; | |
1803 | ||
1804 | if (mask & MAY_APPEND) | |
1805 | av |= FILE__APPEND; | |
1806 | else if (mask & MAY_WRITE) | |
1807 | av |= FILE__WRITE; | |
1808 | ||
1809 | } else { | |
1810 | if (mask & MAY_EXEC) | |
1811 | av |= DIR__SEARCH; | |
1812 | if (mask & MAY_WRITE) | |
1813 | av |= DIR__WRITE; | |
1814 | if (mask & MAY_READ) | |
1815 | av |= DIR__READ; | |
1816 | } | |
1817 | ||
1818 | return av; | |
1819 | } | |
1820 | ||
8b6a5a37 EP |
1821 | /* Convert a Linux file to an access vector. */ |
1822 | static inline u32 file_to_av(struct file *file) | |
1823 | { | |
1824 | u32 av = 0; | |
1825 | ||
1826 | if (file->f_mode & FMODE_READ) | |
1827 | av |= FILE__READ; | |
1828 | if (file->f_mode & FMODE_WRITE) { | |
1829 | if (file->f_flags & O_APPEND) | |
1830 | av |= FILE__APPEND; | |
1831 | else | |
1832 | av |= FILE__WRITE; | |
1833 | } | |
1834 | if (!av) { | |
1835 | /* | |
1836 | * Special file opened with flags 3 for ioctl-only use. | |
1837 | */ | |
1838 | av = FILE__IOCTL; | |
1839 | } | |
1840 | ||
1841 | return av; | |
1842 | } | |
1843 | ||
b0c636b9 | 1844 | /* |
8b6a5a37 | 1845 | * Convert a file to an access vector and include the correct open |
b0c636b9 EP |
1846 | * open permission. |
1847 | */ | |
8b6a5a37 | 1848 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 1849 | { |
8b6a5a37 | 1850 | u32 av = file_to_av(file); |
b0c636b9 | 1851 | |
49b7b8de EP |
1852 | if (selinux_policycap_openperm) |
1853 | av |= FILE__OPEN; | |
1854 | ||
b0c636b9 EP |
1855 | return av; |
1856 | } | |
1857 | ||
1da177e4 LT |
1858 | /* Hook functions begin here. */ |
1859 | ||
9e48858f | 1860 | static int selinux_ptrace_access_check(struct task_struct *child, |
5cd9c58f | 1861 | unsigned int mode) |
1da177e4 | 1862 | { |
1da177e4 LT |
1863 | int rc; |
1864 | ||
9e48858f | 1865 | rc = cap_ptrace_access_check(child, mode); |
1da177e4 LT |
1866 | if (rc) |
1867 | return rc; | |
1868 | ||
69f594a3 | 1869 | if (mode & PTRACE_MODE_READ) { |
275bb41e DH |
1870 | u32 sid = current_sid(); |
1871 | u32 csid = task_sid(child); | |
1872 | return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 SS |
1873 | } |
1874 | ||
3b11a1de | 1875 | return current_has_perm(child, PROCESS__PTRACE); |
5cd9c58f DH |
1876 | } |
1877 | ||
1878 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
1879 | { | |
1880 | int rc; | |
1881 | ||
200ac532 | 1882 | rc = cap_ptrace_traceme(parent); |
5cd9c58f DH |
1883 | if (rc) |
1884 | return rc; | |
1885 | ||
1886 | return task_has_perm(parent, current, PROCESS__PTRACE); | |
1da177e4 LT |
1887 | } |
1888 | ||
1889 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 1890 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 LT |
1891 | { |
1892 | int error; | |
1893 | ||
3b11a1de | 1894 | error = current_has_perm(target, PROCESS__GETCAP); |
1da177e4 LT |
1895 | if (error) |
1896 | return error; | |
1897 | ||
200ac532 | 1898 | return cap_capget(target, effective, inheritable, permitted); |
1da177e4 LT |
1899 | } |
1900 | ||
d84f4f99 DH |
1901 | static int selinux_capset(struct cred *new, const struct cred *old, |
1902 | const kernel_cap_t *effective, | |
1903 | const kernel_cap_t *inheritable, | |
1904 | const kernel_cap_t *permitted) | |
1da177e4 LT |
1905 | { |
1906 | int error; | |
1907 | ||
200ac532 | 1908 | error = cap_capset(new, old, |
d84f4f99 | 1909 | effective, inheritable, permitted); |
1da177e4 LT |
1910 | if (error) |
1911 | return error; | |
1912 | ||
d84f4f99 | 1913 | return cred_has_perm(old, new, PROCESS__SETCAP); |
1da177e4 LT |
1914 | } |
1915 | ||
5626d3e8 JM |
1916 | /* |
1917 | * (This comment used to live with the selinux_task_setuid hook, | |
1918 | * which was removed). | |
1919 | * | |
1920 | * Since setuid only affects the current process, and since the SELinux | |
1921 | * controls are not based on the Linux identity attributes, SELinux does not | |
1922 | * need to control this operation. However, SELinux does control the use of | |
1923 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
1924 | */ | |
1925 | ||
6a9de491 EP |
1926 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
1927 | int cap, int audit) | |
1da177e4 LT |
1928 | { |
1929 | int rc; | |
1930 | ||
6a9de491 | 1931 | rc = cap_capable(cred, ns, cap, audit); |
1da177e4 LT |
1932 | if (rc) |
1933 | return rc; | |
1934 | ||
6a9de491 | 1935 | return cred_has_capability(cred, cap, audit); |
1da177e4 LT |
1936 | } |
1937 | ||
1da177e4 LT |
1938 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
1939 | { | |
88e67f3b | 1940 | const struct cred *cred = current_cred(); |
1da177e4 LT |
1941 | int rc = 0; |
1942 | ||
1943 | if (!sb) | |
1944 | return 0; | |
1945 | ||
1946 | switch (cmds) { | |
828dfe1d EP |
1947 | case Q_SYNC: |
1948 | case Q_QUOTAON: | |
1949 | case Q_QUOTAOFF: | |
1950 | case Q_SETINFO: | |
1951 | case Q_SETQUOTA: | |
88e67f3b | 1952 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
1953 | break; |
1954 | case Q_GETFMT: | |
1955 | case Q_GETINFO: | |
1956 | case Q_GETQUOTA: | |
88e67f3b | 1957 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
1958 | break; |
1959 | default: | |
1960 | rc = 0; /* let the kernel handle invalid cmds */ | |
1961 | break; | |
1da177e4 LT |
1962 | } |
1963 | return rc; | |
1964 | } | |
1965 | ||
1966 | static int selinux_quota_on(struct dentry *dentry) | |
1967 | { | |
88e67f3b DH |
1968 | const struct cred *cred = current_cred(); |
1969 | ||
2875fa00 | 1970 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
1971 | } |
1972 | ||
12b3052c | 1973 | static int selinux_syslog(int type) |
1da177e4 LT |
1974 | { |
1975 | int rc; | |
1976 | ||
1da177e4 | 1977 | switch (type) { |
d78ca3cd KC |
1978 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
1979 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
828dfe1d EP |
1980 | rc = task_has_system(current, SYSTEM__SYSLOG_READ); |
1981 | break; | |
d78ca3cd KC |
1982 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
1983 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
1984 | /* Set level of messages printed to console */ | |
1985 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
828dfe1d EP |
1986 | rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); |
1987 | break; | |
d78ca3cd KC |
1988 | case SYSLOG_ACTION_CLOSE: /* Close log */ |
1989 | case SYSLOG_ACTION_OPEN: /* Open log */ | |
1990 | case SYSLOG_ACTION_READ: /* Read from log */ | |
1991 | case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ | |
1992 | case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ | |
828dfe1d EP |
1993 | default: |
1994 | rc = task_has_system(current, SYSTEM__SYSLOG_MOD); | |
1995 | break; | |
1da177e4 LT |
1996 | } |
1997 | return rc; | |
1998 | } | |
1999 | ||
2000 | /* | |
2001 | * Check that a process has enough memory to allocate a new virtual | |
2002 | * mapping. 0 means there is enough memory for the allocation to | |
2003 | * succeed and -ENOMEM implies there is not. | |
2004 | * | |
1da177e4 LT |
2005 | * Do not audit the selinux permission check, as this is applied to all |
2006 | * processes that allocate mappings. | |
2007 | */ | |
34b4e4aa | 2008 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2009 | { |
2010 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2011 | |
6a9de491 | 2012 | rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN, |
3699c53c | 2013 | SECURITY_CAP_NOAUDIT); |
1da177e4 LT |
2014 | if (rc == 0) |
2015 | cap_sys_admin = 1; | |
2016 | ||
34b4e4aa | 2017 | return __vm_enough_memory(mm, pages, cap_sys_admin); |
1da177e4 LT |
2018 | } |
2019 | ||
2020 | /* binprm security operations */ | |
2021 | ||
a6f76f23 | 2022 | static int selinux_bprm_set_creds(struct linux_binprm *bprm) |
1da177e4 | 2023 | { |
a6f76f23 DH |
2024 | const struct task_security_struct *old_tsec; |
2025 | struct task_security_struct *new_tsec; | |
1da177e4 | 2026 | struct inode_security_struct *isec; |
2bf49690 | 2027 | struct common_audit_data ad; |
496ad9aa | 2028 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2029 | int rc; |
2030 | ||
200ac532 | 2031 | rc = cap_bprm_set_creds(bprm); |
1da177e4 LT |
2032 | if (rc) |
2033 | return rc; | |
2034 | ||
a6f76f23 DH |
2035 | /* SELinux context only depends on initial program or script and not |
2036 | * the script interpreter */ | |
2037 | if (bprm->cred_prepared) | |
1da177e4 LT |
2038 | return 0; |
2039 | ||
a6f76f23 DH |
2040 | old_tsec = current_security(); |
2041 | new_tsec = bprm->cred->security; | |
1da177e4 LT |
2042 | isec = inode->i_security; |
2043 | ||
2044 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2045 | new_tsec->sid = old_tsec->sid; |
2046 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2047 | |
28eba5bf | 2048 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2049 | new_tsec->create_sid = 0; |
2050 | new_tsec->keycreate_sid = 0; | |
2051 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2052 | |
a6f76f23 DH |
2053 | if (old_tsec->exec_sid) { |
2054 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2055 | /* Reset exec SID on execve. */ |
a6f76f23 | 2056 | new_tsec->exec_sid = 0; |
259e5e6c AL |
2057 | |
2058 | /* | |
2059 | * Minimize confusion: if no_new_privs and a transition is | |
2060 | * explicitly requested, then fail the exec. | |
2061 | */ | |
2062 | if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) | |
2063 | return -EPERM; | |
1da177e4 LT |
2064 | } else { |
2065 | /* Check for a default transition on this program. */ | |
a6f76f23 | 2066 | rc = security_transition_sid(old_tsec->sid, isec->sid, |
652bb9b0 EP |
2067 | SECCLASS_PROCESS, NULL, |
2068 | &new_tsec->sid); | |
1da177e4 LT |
2069 | if (rc) |
2070 | return rc; | |
2071 | } | |
2072 | ||
50c205f5 | 2073 | ad.type = LSM_AUDIT_DATA_PATH; |
f48b7399 | 2074 | ad.u.path = bprm->file->f_path; |
1da177e4 | 2075 | |
259e5e6c AL |
2076 | if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) || |
2077 | (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)) | |
a6f76f23 | 2078 | new_tsec->sid = old_tsec->sid; |
1da177e4 | 2079 | |
a6f76f23 DH |
2080 | if (new_tsec->sid == old_tsec->sid) { |
2081 | rc = avc_has_perm(old_tsec->sid, isec->sid, | |
1da177e4 LT |
2082 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2083 | if (rc) | |
2084 | return rc; | |
2085 | } else { | |
2086 | /* Check permissions for the transition. */ | |
a6f76f23 | 2087 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
1da177e4 LT |
2088 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2089 | if (rc) | |
2090 | return rc; | |
2091 | ||
a6f76f23 | 2092 | rc = avc_has_perm(new_tsec->sid, isec->sid, |
1da177e4 LT |
2093 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2094 | if (rc) | |
2095 | return rc; | |
2096 | ||
a6f76f23 DH |
2097 | /* Check for shared state */ |
2098 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
2099 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, | |
2100 | SECCLASS_PROCESS, PROCESS__SHARE, | |
2101 | NULL); | |
2102 | if (rc) | |
2103 | return -EPERM; | |
2104 | } | |
2105 | ||
2106 | /* Make sure that anyone attempting to ptrace over a task that | |
2107 | * changes its SID has the appropriate permit */ | |
2108 | if (bprm->unsafe & | |
2109 | (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { | |
2110 | struct task_struct *tracer; | |
2111 | struct task_security_struct *sec; | |
2112 | u32 ptsid = 0; | |
2113 | ||
2114 | rcu_read_lock(); | |
06d98473 | 2115 | tracer = ptrace_parent(current); |
a6f76f23 DH |
2116 | if (likely(tracer != NULL)) { |
2117 | sec = __task_cred(tracer)->security; | |
2118 | ptsid = sec->sid; | |
2119 | } | |
2120 | rcu_read_unlock(); | |
2121 | ||
2122 | if (ptsid != 0) { | |
2123 | rc = avc_has_perm(ptsid, new_tsec->sid, | |
2124 | SECCLASS_PROCESS, | |
2125 | PROCESS__PTRACE, NULL); | |
2126 | if (rc) | |
2127 | return -EPERM; | |
2128 | } | |
2129 | } | |
1da177e4 | 2130 | |
a6f76f23 DH |
2131 | /* Clear any possibly unsafe personality bits on exec: */ |
2132 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
1da177e4 LT |
2133 | } |
2134 | ||
1da177e4 LT |
2135 | return 0; |
2136 | } | |
2137 | ||
828dfe1d | 2138 | static int selinux_bprm_secureexec(struct linux_binprm *bprm) |
1da177e4 | 2139 | { |
5fb49870 | 2140 | const struct task_security_struct *tsec = current_security(); |
275bb41e | 2141 | u32 sid, osid; |
1da177e4 LT |
2142 | int atsecure = 0; |
2143 | ||
275bb41e DH |
2144 | sid = tsec->sid; |
2145 | osid = tsec->osid; | |
2146 | ||
2147 | if (osid != sid) { | |
1da177e4 LT |
2148 | /* Enable secure mode for SIDs transitions unless |
2149 | the noatsecure permission is granted between | |
2150 | the two SIDs, i.e. ahp returns 0. */ | |
275bb41e | 2151 | atsecure = avc_has_perm(osid, sid, |
a6f76f23 DH |
2152 | SECCLASS_PROCESS, |
2153 | PROCESS__NOATSECURE, NULL); | |
1da177e4 LT |
2154 | } |
2155 | ||
200ac532 | 2156 | return (atsecure || cap_bprm_secureexec(bprm)); |
1da177e4 LT |
2157 | } |
2158 | ||
c3c073f8 AV |
2159 | static int match_file(const void *p, struct file *file, unsigned fd) |
2160 | { | |
2161 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2162 | } | |
2163 | ||
1da177e4 | 2164 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2165 | static inline void flush_unauthorized_files(const struct cred *cred, |
2166 | struct files_struct *files) | |
1da177e4 | 2167 | { |
1da177e4 | 2168 | struct file *file, *devnull = NULL; |
b20c8122 | 2169 | struct tty_struct *tty; |
24ec839c | 2170 | int drop_tty = 0; |
c3c073f8 | 2171 | unsigned n; |
1da177e4 | 2172 | |
24ec839c | 2173 | tty = get_current_tty(); |
1da177e4 | 2174 | if (tty) { |
ee2ffa0d | 2175 | spin_lock(&tty_files_lock); |
37dd0bd0 | 2176 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2177 | struct tty_file_private *file_priv; |
37dd0bd0 | 2178 | |
1da177e4 | 2179 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2180 | Use file_path_has_perm on the tty path directly |
2181 | rather than using file_has_perm, as this particular | |
2182 | open file may belong to another process and we are | |
2183 | only interested in the inode-based check here. */ | |
d996b62a NP |
2184 | file_priv = list_first_entry(&tty->tty_files, |
2185 | struct tty_file_private, list); | |
2186 | file = file_priv->file; | |
13f8e981 | 2187 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2188 | drop_tty = 1; |
1da177e4 | 2189 | } |
ee2ffa0d | 2190 | spin_unlock(&tty_files_lock); |
452a00d2 | 2191 | tty_kref_put(tty); |
1da177e4 | 2192 | } |
98a27ba4 EB |
2193 | /* Reset controlling tty. */ |
2194 | if (drop_tty) | |
2195 | no_tty(); | |
1da177e4 LT |
2196 | |
2197 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2198 | n = iterate_fd(files, 0, match_file, cred); |
2199 | if (!n) /* none found? */ | |
2200 | return; | |
1da177e4 | 2201 | |
c3c073f8 | 2202 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2203 | if (IS_ERR(devnull)) |
2204 | devnull = NULL; | |
2205 | /* replace all the matching ones with this */ | |
2206 | do { | |
2207 | replace_fd(n - 1, devnull, 0); | |
2208 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2209 | if (devnull) | |
c3c073f8 | 2210 | fput(devnull); |
1da177e4 LT |
2211 | } |
2212 | ||
a6f76f23 DH |
2213 | /* |
2214 | * Prepare a process for imminent new credential changes due to exec | |
2215 | */ | |
2216 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2217 | { |
a6f76f23 DH |
2218 | struct task_security_struct *new_tsec; |
2219 | struct rlimit *rlim, *initrlim; | |
2220 | int rc, i; | |
d84f4f99 | 2221 | |
a6f76f23 DH |
2222 | new_tsec = bprm->cred->security; |
2223 | if (new_tsec->sid == new_tsec->osid) | |
2224 | return; | |
1da177e4 | 2225 | |
a6f76f23 DH |
2226 | /* Close files for which the new task SID is not authorized. */ |
2227 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2228 | |
a6f76f23 DH |
2229 | /* Always clear parent death signal on SID transitions. */ |
2230 | current->pdeath_signal = 0; | |
0356357c | 2231 | |
a6f76f23 DH |
2232 | /* Check whether the new SID can inherit resource limits from the old |
2233 | * SID. If not, reset all soft limits to the lower of the current | |
2234 | * task's hard limit and the init task's soft limit. | |
2235 | * | |
2236 | * Note that the setting of hard limits (even to lower them) can be | |
2237 | * controlled by the setrlimit check. The inclusion of the init task's | |
2238 | * soft limit into the computation is to avoid resetting soft limits | |
2239 | * higher than the default soft limit for cases where the default is | |
2240 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2241 | */ | |
2242 | rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
2243 | PROCESS__RLIMITINH, NULL); | |
2244 | if (rc) { | |
eb2d55a3 ON |
2245 | /* protect against do_prlimit() */ |
2246 | task_lock(current); | |
a6f76f23 DH |
2247 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2248 | rlim = current->signal->rlim + i; | |
2249 | initrlim = init_task.signal->rlim + i; | |
2250 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2251 | } |
eb2d55a3 ON |
2252 | task_unlock(current); |
2253 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2254 | } |
2255 | } | |
2256 | ||
2257 | /* | |
a6f76f23 DH |
2258 | * Clean up the process immediately after the installation of new credentials |
2259 | * due to exec | |
1da177e4 | 2260 | */ |
a6f76f23 | 2261 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2262 | { |
a6f76f23 | 2263 | const struct task_security_struct *tsec = current_security(); |
1da177e4 | 2264 | struct itimerval itimer; |
a6f76f23 | 2265 | u32 osid, sid; |
1da177e4 LT |
2266 | int rc, i; |
2267 | ||
a6f76f23 DH |
2268 | osid = tsec->osid; |
2269 | sid = tsec->sid; | |
2270 | ||
2271 | if (sid == osid) | |
1da177e4 LT |
2272 | return; |
2273 | ||
a6f76f23 DH |
2274 | /* Check whether the new SID can inherit signal state from the old SID. |
2275 | * If not, clear itimers to avoid subsequent signal generation and | |
2276 | * flush and unblock signals. | |
2277 | * | |
2278 | * This must occur _after_ the task SID has been updated so that any | |
2279 | * kill done after the flush will be checked against the new SID. | |
2280 | */ | |
2281 | rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 LT |
2282 | if (rc) { |
2283 | memset(&itimer, 0, sizeof itimer); | |
2284 | for (i = 0; i < 3; i++) | |
2285 | do_setitimer(i, &itimer, NULL); | |
1da177e4 | 2286 | spin_lock_irq(¤t->sighand->siglock); |
3bcac026 DH |
2287 | if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) { |
2288 | __flush_signals(current); | |
2289 | flush_signal_handlers(current, 1); | |
2290 | sigemptyset(¤t->blocked); | |
2291 | } | |
1da177e4 LT |
2292 | spin_unlock_irq(¤t->sighand->siglock); |
2293 | } | |
2294 | ||
a6f76f23 DH |
2295 | /* Wake up the parent if it is waiting so that it can recheck |
2296 | * wait permission to the new task SID. */ | |
ecd6de3c | 2297 | read_lock(&tasklist_lock); |
0b7570e7 | 2298 | __wake_up_parent(current, current->real_parent); |
ecd6de3c | 2299 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2300 | } |
2301 | ||
2302 | /* superblock security operations */ | |
2303 | ||
2304 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2305 | { | |
2306 | return superblock_alloc_security(sb); | |
2307 | } | |
2308 | ||
2309 | static void selinux_sb_free_security(struct super_block *sb) | |
2310 | { | |
2311 | superblock_free_security(sb); | |
2312 | } | |
2313 | ||
2314 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2315 | { | |
2316 | if (plen > olen) | |
2317 | return 0; | |
2318 | ||
2319 | return !memcmp(prefix, option, plen); | |
2320 | } | |
2321 | ||
2322 | static inline int selinux_option(char *option, int len) | |
2323 | { | |
832cbd9a EP |
2324 | return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || |
2325 | match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || | |
2326 | match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || | |
11689d47 DQ |
2327 | match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || |
2328 | match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); | |
1da177e4 LT |
2329 | } |
2330 | ||
2331 | static inline void take_option(char **to, char *from, int *first, int len) | |
2332 | { | |
2333 | if (!*first) { | |
2334 | **to = ','; | |
2335 | *to += 1; | |
3528a953 | 2336 | } else |
1da177e4 LT |
2337 | *first = 0; |
2338 | memcpy(*to, from, len); | |
2339 | *to += len; | |
2340 | } | |
2341 | ||
828dfe1d EP |
2342 | static inline void take_selinux_option(char **to, char *from, int *first, |
2343 | int len) | |
3528a953 CO |
2344 | { |
2345 | int current_size = 0; | |
2346 | ||
2347 | if (!*first) { | |
2348 | **to = '|'; | |
2349 | *to += 1; | |
828dfe1d | 2350 | } else |
3528a953 CO |
2351 | *first = 0; |
2352 | ||
2353 | while (current_size < len) { | |
2354 | if (*from != '"') { | |
2355 | **to = *from; | |
2356 | *to += 1; | |
2357 | } | |
2358 | from += 1; | |
2359 | current_size += 1; | |
2360 | } | |
2361 | } | |
2362 | ||
e0007529 | 2363 | static int selinux_sb_copy_data(char *orig, char *copy) |
1da177e4 LT |
2364 | { |
2365 | int fnosec, fsec, rc = 0; | |
2366 | char *in_save, *in_curr, *in_end; | |
2367 | char *sec_curr, *nosec_save, *nosec; | |
3528a953 | 2368 | int open_quote = 0; |
1da177e4 LT |
2369 | |
2370 | in_curr = orig; | |
2371 | sec_curr = copy; | |
2372 | ||
1da177e4 LT |
2373 | nosec = (char *)get_zeroed_page(GFP_KERNEL); |
2374 | if (!nosec) { | |
2375 | rc = -ENOMEM; | |
2376 | goto out; | |
2377 | } | |
2378 | ||
2379 | nosec_save = nosec; | |
2380 | fnosec = fsec = 1; | |
2381 | in_save = in_end = orig; | |
2382 | ||
2383 | do { | |
3528a953 CO |
2384 | if (*in_end == '"') |
2385 | open_quote = !open_quote; | |
2386 | if ((*in_end == ',' && open_quote == 0) || | |
2387 | *in_end == '\0') { | |
1da177e4 LT |
2388 | int len = in_end - in_curr; |
2389 | ||
2390 | if (selinux_option(in_curr, len)) | |
3528a953 | 2391 | take_selinux_option(&sec_curr, in_curr, &fsec, len); |
1da177e4 LT |
2392 | else |
2393 | take_option(&nosec, in_curr, &fnosec, len); | |
2394 | ||
2395 | in_curr = in_end + 1; | |
2396 | } | |
2397 | } while (*in_end++); | |
2398 | ||
6931dfc9 | 2399 | strcpy(in_save, nosec_save); |
da3caa20 | 2400 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
2401 | out: |
2402 | return rc; | |
2403 | } | |
2404 | ||
026eb167 EP |
2405 | static int selinux_sb_remount(struct super_block *sb, void *data) |
2406 | { | |
2407 | int rc, i, *flags; | |
2408 | struct security_mnt_opts opts; | |
2409 | char *secdata, **mount_options; | |
2410 | struct superblock_security_struct *sbsec = sb->s_security; | |
2411 | ||
2412 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2413 | return 0; | |
2414 | ||
2415 | if (!data) | |
2416 | return 0; | |
2417 | ||
2418 | if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) | |
2419 | return 0; | |
2420 | ||
2421 | security_init_mnt_opts(&opts); | |
2422 | secdata = alloc_secdata(); | |
2423 | if (!secdata) | |
2424 | return -ENOMEM; | |
2425 | rc = selinux_sb_copy_data(data, secdata); | |
2426 | if (rc) | |
2427 | goto out_free_secdata; | |
2428 | ||
2429 | rc = selinux_parse_opts_str(secdata, &opts); | |
2430 | if (rc) | |
2431 | goto out_free_secdata; | |
2432 | ||
2433 | mount_options = opts.mnt_opts; | |
2434 | flags = opts.mnt_opts_flags; | |
2435 | ||
2436 | for (i = 0; i < opts.num_mnt_opts; i++) { | |
2437 | u32 sid; | |
2438 | size_t len; | |
2439 | ||
2440 | if (flags[i] == SE_SBLABELSUPP) | |
2441 | continue; | |
2442 | len = strlen(mount_options[i]); | |
2443 | rc = security_context_to_sid(mount_options[i], len, &sid); | |
2444 | if (rc) { | |
2445 | printk(KERN_WARNING "SELinux: security_context_to_sid" | |
2446 | "(%s) failed for (dev %s, type %s) errno=%d\n", | |
2447 | mount_options[i], sb->s_id, sb->s_type->name, rc); | |
2448 | goto out_free_opts; | |
2449 | } | |
2450 | rc = -EINVAL; | |
2451 | switch (flags[i]) { | |
2452 | case FSCONTEXT_MNT: | |
2453 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) | |
2454 | goto out_bad_option; | |
2455 | break; | |
2456 | case CONTEXT_MNT: | |
2457 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2458 | goto out_bad_option; | |
2459 | break; | |
2460 | case ROOTCONTEXT_MNT: { | |
2461 | struct inode_security_struct *root_isec; | |
2462 | root_isec = sb->s_root->d_inode->i_security; | |
2463 | ||
2464 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2465 | goto out_bad_option; | |
2466 | break; | |
2467 | } | |
2468 | case DEFCONTEXT_MNT: | |
2469 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2470 | goto out_bad_option; | |
2471 | break; | |
2472 | default: | |
2473 | goto out_free_opts; | |
2474 | } | |
2475 | } | |
2476 | ||
2477 | rc = 0; | |
2478 | out_free_opts: | |
2479 | security_free_mnt_opts(&opts); | |
2480 | out_free_secdata: | |
2481 | free_secdata(secdata); | |
2482 | return rc; | |
2483 | out_bad_option: | |
2484 | printk(KERN_WARNING "SELinux: unable to change security options " | |
2485 | "during remount (dev %s, type=%s)\n", sb->s_id, | |
2486 | sb->s_type->name); | |
2487 | goto out_free_opts; | |
2488 | } | |
2489 | ||
12204e24 | 2490 | static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) |
1da177e4 | 2491 | { |
88e67f3b | 2492 | const struct cred *cred = current_cred(); |
2bf49690 | 2493 | struct common_audit_data ad; |
1da177e4 LT |
2494 | int rc; |
2495 | ||
2496 | rc = superblock_doinit(sb, data); | |
2497 | if (rc) | |
2498 | return rc; | |
2499 | ||
74192246 JM |
2500 | /* Allow all mounts performed by the kernel */ |
2501 | if (flags & MS_KERNMOUNT) | |
2502 | return 0; | |
2503 | ||
50c205f5 | 2504 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2505 | ad.u.dentry = sb->s_root; |
88e67f3b | 2506 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2507 | } |
2508 | ||
726c3342 | 2509 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2510 | { |
88e67f3b | 2511 | const struct cred *cred = current_cred(); |
2bf49690 | 2512 | struct common_audit_data ad; |
1da177e4 | 2513 | |
50c205f5 | 2514 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2515 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2516 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2517 | } |
2518 | ||
808d4e3c | 2519 | static int selinux_mount(const char *dev_name, |
b5266eb4 | 2520 | struct path *path, |
808d4e3c | 2521 | const char *type, |
828dfe1d EP |
2522 | unsigned long flags, |
2523 | void *data) | |
1da177e4 | 2524 | { |
88e67f3b | 2525 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2526 | |
2527 | if (flags & MS_REMOUNT) | |
d8c9584e | 2528 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2529 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2530 | else |
2875fa00 | 2531 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2532 | } |
2533 | ||
2534 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2535 | { | |
88e67f3b | 2536 | const struct cred *cred = current_cred(); |
1da177e4 | 2537 | |
88e67f3b | 2538 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2539 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2540 | } |
2541 | ||
2542 | /* inode security operations */ | |
2543 | ||
2544 | static int selinux_inode_alloc_security(struct inode *inode) | |
2545 | { | |
2546 | return inode_alloc_security(inode); | |
2547 | } | |
2548 | ||
2549 | static void selinux_inode_free_security(struct inode *inode) | |
2550 | { | |
2551 | inode_free_security(inode); | |
2552 | } | |
2553 | ||
d47be3df DQ |
2554 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
2555 | struct qstr *name, void **ctx, | |
2556 | u32 *ctxlen) | |
2557 | { | |
2558 | const struct cred *cred = current_cred(); | |
2559 | struct task_security_struct *tsec; | |
2560 | struct inode_security_struct *dsec; | |
2561 | struct superblock_security_struct *sbsec; | |
2562 | struct inode *dir = dentry->d_parent->d_inode; | |
2563 | u32 newsid; | |
2564 | int rc; | |
2565 | ||
2566 | tsec = cred->security; | |
2567 | dsec = dir->i_security; | |
2568 | sbsec = dir->i_sb->s_security; | |
2569 | ||
2570 | if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { | |
2571 | newsid = tsec->create_sid; | |
2572 | } else { | |
2573 | rc = security_transition_sid(tsec->sid, dsec->sid, | |
2574 | inode_mode_to_security_class(mode), | |
2575 | name, | |
2576 | &newsid); | |
2577 | if (rc) { | |
2578 | printk(KERN_WARNING | |
2579 | "%s: security_transition_sid failed, rc=%d\n", | |
2580 | __func__, -rc); | |
2581 | return rc; | |
2582 | } | |
2583 | } | |
2584 | ||
2585 | return security_sid_to_context(newsid, (char **)ctx, ctxlen); | |
2586 | } | |
2587 | ||
5e41ff9e | 2588 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
2589 | const struct qstr *qstr, |
2590 | const char **name, | |
2a7dba39 | 2591 | void **value, size_t *len) |
5e41ff9e | 2592 | { |
5fb49870 | 2593 | const struct task_security_struct *tsec = current_security(); |
5e41ff9e SS |
2594 | struct inode_security_struct *dsec; |
2595 | struct superblock_security_struct *sbsec; | |
275bb41e | 2596 | u32 sid, newsid, clen; |
5e41ff9e | 2597 | int rc; |
9548906b | 2598 | char *context; |
5e41ff9e | 2599 | |
5e41ff9e SS |
2600 | dsec = dir->i_security; |
2601 | sbsec = dir->i_sb->s_security; | |
5e41ff9e | 2602 | |
275bb41e DH |
2603 | sid = tsec->sid; |
2604 | newsid = tsec->create_sid; | |
2605 | ||
415103f9 EP |
2606 | if ((sbsec->flags & SE_SBINITIALIZED) && |
2607 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) | |
2608 | newsid = sbsec->mntpoint_sid; | |
2609 | else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { | |
275bb41e | 2610 | rc = security_transition_sid(sid, dsec->sid, |
5e41ff9e | 2611 | inode_mode_to_security_class(inode->i_mode), |
652bb9b0 | 2612 | qstr, &newsid); |
5e41ff9e SS |
2613 | if (rc) { |
2614 | printk(KERN_WARNING "%s: " | |
2615 | "security_transition_sid failed, rc=%d (dev=%s " | |
2616 | "ino=%ld)\n", | |
dd6f953a | 2617 | __func__, |
5e41ff9e SS |
2618 | -rc, inode->i_sb->s_id, inode->i_ino); |
2619 | return rc; | |
2620 | } | |
2621 | } | |
2622 | ||
296fddf7 | 2623 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 2624 | if (sbsec->flags & SE_SBINITIALIZED) { |
296fddf7 EP |
2625 | struct inode_security_struct *isec = inode->i_security; |
2626 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
2627 | isec->sid = newsid; | |
2628 | isec->initialized = 1; | |
2629 | } | |
5e41ff9e | 2630 | |
cd89596f | 2631 | if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP)) |
25a74f3b SS |
2632 | return -EOPNOTSUPP; |
2633 | ||
9548906b TH |
2634 | if (name) |
2635 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 2636 | |
570bc1c2 | 2637 | if (value && len) { |
12b29f34 | 2638 | rc = security_sid_to_context_force(newsid, &context, &clen); |
9548906b | 2639 | if (rc) |
570bc1c2 | 2640 | return rc; |
570bc1c2 SS |
2641 | *value = context; |
2642 | *len = clen; | |
5e41ff9e | 2643 | } |
5e41ff9e | 2644 | |
5e41ff9e SS |
2645 | return 0; |
2646 | } | |
2647 | ||
4acdaf27 | 2648 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
2649 | { |
2650 | return may_create(dir, dentry, SECCLASS_FILE); | |
2651 | } | |
2652 | ||
1da177e4 LT |
2653 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2654 | { | |
1da177e4 LT |
2655 | return may_link(dir, old_dentry, MAY_LINK); |
2656 | } | |
2657 | ||
1da177e4 LT |
2658 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2659 | { | |
1da177e4 LT |
2660 | return may_link(dir, dentry, MAY_UNLINK); |
2661 | } | |
2662 | ||
2663 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2664 | { | |
2665 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2666 | } | |
2667 | ||
18bb1db3 | 2668 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
2669 | { |
2670 | return may_create(dir, dentry, SECCLASS_DIR); | |
2671 | } | |
2672 | ||
1da177e4 LT |
2673 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2674 | { | |
2675 | return may_link(dir, dentry, MAY_RMDIR); | |
2676 | } | |
2677 | ||
1a67aafb | 2678 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 2679 | { |
1da177e4 LT |
2680 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
2681 | } | |
2682 | ||
1da177e4 | 2683 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 2684 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
2685 | { |
2686 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2687 | } | |
2688 | ||
1da177e4 LT |
2689 | static int selinux_inode_readlink(struct dentry *dentry) |
2690 | { | |
88e67f3b DH |
2691 | const struct cred *cred = current_cred(); |
2692 | ||
2875fa00 | 2693 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
2694 | } |
2695 | ||
2696 | static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) | |
2697 | { | |
88e67f3b | 2698 | const struct cred *cred = current_cred(); |
1da177e4 | 2699 | |
2875fa00 | 2700 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
2701 | } |
2702 | ||
d4cf970d EP |
2703 | static noinline int audit_inode_permission(struct inode *inode, |
2704 | u32 perms, u32 audited, u32 denied, | |
2705 | unsigned flags) | |
1da177e4 | 2706 | { |
b782e0a6 | 2707 | struct common_audit_data ad; |
d4cf970d EP |
2708 | struct inode_security_struct *isec = inode->i_security; |
2709 | int rc; | |
2710 | ||
50c205f5 | 2711 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
2712 | ad.u.inode = inode; |
2713 | ||
2714 | rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, | |
2715 | audited, denied, &ad, flags); | |
2716 | if (rc) | |
2717 | return rc; | |
2718 | return 0; | |
2719 | } | |
2720 | ||
e74f71eb | 2721 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 2722 | { |
88e67f3b | 2723 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
2724 | u32 perms; |
2725 | bool from_access; | |
cf1dd1da | 2726 | unsigned flags = mask & MAY_NOT_BLOCK; |
2e334057 EP |
2727 | struct inode_security_struct *isec; |
2728 | u32 sid; | |
2729 | struct av_decision avd; | |
2730 | int rc, rc2; | |
2731 | u32 audited, denied; | |
1da177e4 | 2732 | |
b782e0a6 | 2733 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
2734 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
2735 | ||
b782e0a6 EP |
2736 | /* No permission to check. Existence test. */ |
2737 | if (!mask) | |
1da177e4 | 2738 | return 0; |
1da177e4 | 2739 | |
2e334057 | 2740 | validate_creds(cred); |
b782e0a6 | 2741 | |
2e334057 EP |
2742 | if (unlikely(IS_PRIVATE(inode))) |
2743 | return 0; | |
b782e0a6 EP |
2744 | |
2745 | perms = file_mask_to_av(inode->i_mode, mask); | |
2746 | ||
2e334057 EP |
2747 | sid = cred_sid(cred); |
2748 | isec = inode->i_security; | |
2749 | ||
2750 | rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd); | |
2751 | audited = avc_audit_required(perms, &avd, rc, | |
2752 | from_access ? FILE__AUDIT_ACCESS : 0, | |
2753 | &denied); | |
2754 | if (likely(!audited)) | |
2755 | return rc; | |
2756 | ||
d4cf970d | 2757 | rc2 = audit_inode_permission(inode, perms, audited, denied, flags); |
2e334057 EP |
2758 | if (rc2) |
2759 | return rc2; | |
2760 | return rc; | |
1da177e4 LT |
2761 | } |
2762 | ||
2763 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
2764 | { | |
88e67f3b | 2765 | const struct cred *cred = current_cred(); |
bc6a6008 | 2766 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 2767 | __u32 av = FILE__WRITE; |
1da177e4 | 2768 | |
bc6a6008 AW |
2769 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
2770 | if (ia_valid & ATTR_FORCE) { | |
2771 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
2772 | ATTR_FORCE); | |
2773 | if (!ia_valid) | |
2774 | return 0; | |
2775 | } | |
1da177e4 | 2776 | |
bc6a6008 AW |
2777 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
2778 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 2779 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 2780 | |
3d2195c3 | 2781 | if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE)) |
95dbf739 EP |
2782 | av |= FILE__OPEN; |
2783 | ||
2784 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
2785 | } |
2786 | ||
2787 | static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) | |
2788 | { | |
88e67f3b | 2789 | const struct cred *cred = current_cred(); |
2875fa00 EP |
2790 | struct path path; |
2791 | ||
2792 | path.dentry = dentry; | |
2793 | path.mnt = mnt; | |
88e67f3b | 2794 | |
2875fa00 | 2795 | return path_has_perm(cred, &path, FILE__GETATTR); |
1da177e4 LT |
2796 | } |
2797 | ||
8f0cfa52 | 2798 | static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) |
b5376771 | 2799 | { |
88e67f3b DH |
2800 | const struct cred *cred = current_cred(); |
2801 | ||
b5376771 SH |
2802 | if (!strncmp(name, XATTR_SECURITY_PREFIX, |
2803 | sizeof XATTR_SECURITY_PREFIX - 1)) { | |
2804 | if (!strcmp(name, XATTR_NAME_CAPS)) { | |
2805 | if (!capable(CAP_SETFCAP)) | |
2806 | return -EPERM; | |
2807 | } else if (!capable(CAP_SYS_ADMIN)) { | |
2808 | /* A different attribute in the security namespace. | |
2809 | Restrict to administrator. */ | |
2810 | return -EPERM; | |
2811 | } | |
2812 | } | |
2813 | ||
2814 | /* Not an attribute we recognize, so just check the | |
2815 | ordinary setattr permission. */ | |
2875fa00 | 2816 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
b5376771 SH |
2817 | } |
2818 | ||
8f0cfa52 DH |
2819 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
2820 | const void *value, size_t size, int flags) | |
1da177e4 | 2821 | { |
1da177e4 LT |
2822 | struct inode *inode = dentry->d_inode; |
2823 | struct inode_security_struct *isec = inode->i_security; | |
2824 | struct superblock_security_struct *sbsec; | |
2bf49690 | 2825 | struct common_audit_data ad; |
275bb41e | 2826 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
2827 | int rc = 0; |
2828 | ||
b5376771 SH |
2829 | if (strcmp(name, XATTR_NAME_SELINUX)) |
2830 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
2831 | |
2832 | sbsec = inode->i_sb->s_security; | |
cd89596f | 2833 | if (!(sbsec->flags & SE_SBLABELSUPP)) |
1da177e4 LT |
2834 | return -EOPNOTSUPP; |
2835 | ||
2e149670 | 2836 | if (!inode_owner_or_capable(inode)) |
1da177e4 LT |
2837 | return -EPERM; |
2838 | ||
50c205f5 | 2839 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2840 | ad.u.dentry = dentry; |
1da177e4 | 2841 | |
275bb41e | 2842 | rc = avc_has_perm(sid, isec->sid, isec->sclass, |
1da177e4 LT |
2843 | FILE__RELABELFROM, &ad); |
2844 | if (rc) | |
2845 | return rc; | |
2846 | ||
2847 | rc = security_context_to_sid(value, size, &newsid); | |
12b29f34 | 2848 | if (rc == -EINVAL) { |
d6ea83ec EP |
2849 | if (!capable(CAP_MAC_ADMIN)) { |
2850 | struct audit_buffer *ab; | |
2851 | size_t audit_size; | |
2852 | const char *str; | |
2853 | ||
2854 | /* We strip a nul only if it is at the end, otherwise the | |
2855 | * context contains a nul and we should audit that */ | |
e3fea3f7 AV |
2856 | if (value) { |
2857 | str = value; | |
2858 | if (str[size - 1] == '\0') | |
2859 | audit_size = size - 1; | |
2860 | else | |
2861 | audit_size = size; | |
2862 | } else { | |
2863 | str = ""; | |
2864 | audit_size = 0; | |
2865 | } | |
d6ea83ec EP |
2866 | ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); |
2867 | audit_log_format(ab, "op=setxattr invalid_context="); | |
2868 | audit_log_n_untrustedstring(ab, value, audit_size); | |
2869 | audit_log_end(ab); | |
2870 | ||
12b29f34 | 2871 | return rc; |
d6ea83ec | 2872 | } |
12b29f34 SS |
2873 | rc = security_context_to_sid_force(value, size, &newsid); |
2874 | } | |
1da177e4 LT |
2875 | if (rc) |
2876 | return rc; | |
2877 | ||
275bb41e | 2878 | rc = avc_has_perm(sid, newsid, isec->sclass, |
1da177e4 LT |
2879 | FILE__RELABELTO, &ad); |
2880 | if (rc) | |
2881 | return rc; | |
2882 | ||
275bb41e | 2883 | rc = security_validate_transition(isec->sid, newsid, sid, |
828dfe1d | 2884 | isec->sclass); |
1da177e4 LT |
2885 | if (rc) |
2886 | return rc; | |
2887 | ||
2888 | return avc_has_perm(newsid, | |
2889 | sbsec->sid, | |
2890 | SECCLASS_FILESYSTEM, | |
2891 | FILESYSTEM__ASSOCIATE, | |
2892 | &ad); | |
2893 | } | |
2894 | ||
8f0cfa52 | 2895 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 2896 | const void *value, size_t size, |
8f0cfa52 | 2897 | int flags) |
1da177e4 LT |
2898 | { |
2899 | struct inode *inode = dentry->d_inode; | |
2900 | struct inode_security_struct *isec = inode->i_security; | |
2901 | u32 newsid; | |
2902 | int rc; | |
2903 | ||
2904 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
2905 | /* Not an attribute we recognize, so nothing to do. */ | |
2906 | return; | |
2907 | } | |
2908 | ||
12b29f34 | 2909 | rc = security_context_to_sid_force(value, size, &newsid); |
1da177e4 | 2910 | if (rc) { |
12b29f34 SS |
2911 | printk(KERN_ERR "SELinux: unable to map context to SID" |
2912 | "for (%s, %lu), rc=%d\n", | |
2913 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
2914 | return; |
2915 | } | |
2916 | ||
aa9c2669 | 2917 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 2918 | isec->sid = newsid; |
aa9c2669 DQ |
2919 | isec->initialized = 1; |
2920 | ||
1da177e4 LT |
2921 | return; |
2922 | } | |
2923 | ||
8f0cfa52 | 2924 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 2925 | { |
88e67f3b DH |
2926 | const struct cred *cred = current_cred(); |
2927 | ||
2875fa00 | 2928 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
2929 | } |
2930 | ||
828dfe1d | 2931 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 2932 | { |
88e67f3b DH |
2933 | const struct cred *cred = current_cred(); |
2934 | ||
2875fa00 | 2935 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
2936 | } |
2937 | ||
8f0cfa52 | 2938 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 2939 | { |
b5376771 SH |
2940 | if (strcmp(name, XATTR_NAME_SELINUX)) |
2941 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
2942 | |
2943 | /* No one is allowed to remove a SELinux security label. | |
2944 | You can change the label, but all data must be labeled. */ | |
2945 | return -EACCES; | |
2946 | } | |
2947 | ||
d381d8a9 | 2948 | /* |
abc69bb6 | 2949 | * Copy the inode security context value to the user. |
d381d8a9 JM |
2950 | * |
2951 | * Permission check is handled by selinux_inode_getxattr hook. | |
2952 | */ | |
42492594 | 2953 | static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 2954 | { |
42492594 DQ |
2955 | u32 size; |
2956 | int error; | |
2957 | char *context = NULL; | |
1da177e4 | 2958 | struct inode_security_struct *isec = inode->i_security; |
d381d8a9 | 2959 | |
8c8570fb DK |
2960 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
2961 | return -EOPNOTSUPP; | |
d381d8a9 | 2962 | |
abc69bb6 SS |
2963 | /* |
2964 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
2965 | * value even if it is not defined by current policy; otherwise, | |
2966 | * use the in-core value under current policy. | |
2967 | * Use the non-auditing forms of the permission checks since | |
2968 | * getxattr may be called by unprivileged processes commonly | |
2969 | * and lack of permission just means that we fall back to the | |
2970 | * in-core context value, not a denial. | |
2971 | */ | |
6a9de491 | 2972 | error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN, |
3699c53c | 2973 | SECURITY_CAP_NOAUDIT); |
abc69bb6 SS |
2974 | if (!error) |
2975 | error = security_sid_to_context_force(isec->sid, &context, | |
2976 | &size); | |
2977 | else | |
2978 | error = security_sid_to_context(isec->sid, &context, &size); | |
42492594 DQ |
2979 | if (error) |
2980 | return error; | |
2981 | error = size; | |
2982 | if (alloc) { | |
2983 | *buffer = context; | |
2984 | goto out_nofree; | |
2985 | } | |
2986 | kfree(context); | |
2987 | out_nofree: | |
2988 | return error; | |
1da177e4 LT |
2989 | } |
2990 | ||
2991 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 2992 | const void *value, size_t size, int flags) |
1da177e4 LT |
2993 | { |
2994 | struct inode_security_struct *isec = inode->i_security; | |
2995 | u32 newsid; | |
2996 | int rc; | |
2997 | ||
2998 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
2999 | return -EOPNOTSUPP; | |
3000 | ||
3001 | if (!value || !size) | |
3002 | return -EACCES; | |
3003 | ||
828dfe1d | 3004 | rc = security_context_to_sid((void *)value, size, &newsid); |
1da177e4 LT |
3005 | if (rc) |
3006 | return rc; | |
3007 | ||
aa9c2669 | 3008 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3009 | isec->sid = newsid; |
ddd29ec6 | 3010 | isec->initialized = 1; |
1da177e4 LT |
3011 | return 0; |
3012 | } | |
3013 | ||
3014 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3015 | { | |
3016 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3017 | if (buffer && len <= buffer_size) | |
3018 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3019 | return len; | |
3020 | } | |
3021 | ||
713a04ae AD |
3022 | static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) |
3023 | { | |
3024 | struct inode_security_struct *isec = inode->i_security; | |
3025 | *secid = isec->sid; | |
3026 | } | |
3027 | ||
1da177e4 LT |
3028 | /* file security operations */ |
3029 | ||
788e7dd4 | 3030 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3031 | { |
88e67f3b | 3032 | const struct cred *cred = current_cred(); |
496ad9aa | 3033 | struct inode *inode = file_inode(file); |
1da177e4 | 3034 | |
1da177e4 LT |
3035 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3036 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3037 | mask |= MAY_APPEND; | |
3038 | ||
389fb800 PM |
3039 | return file_has_perm(cred, file, |
3040 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3041 | } |
3042 | ||
788e7dd4 YN |
3043 | static int selinux_file_permission(struct file *file, int mask) |
3044 | { | |
496ad9aa | 3045 | struct inode *inode = file_inode(file); |
20dda18b SS |
3046 | struct file_security_struct *fsec = file->f_security; |
3047 | struct inode_security_struct *isec = inode->i_security; | |
3048 | u32 sid = current_sid(); | |
3049 | ||
389fb800 | 3050 | if (!mask) |
788e7dd4 YN |
3051 | /* No permission to check. Existence test. */ |
3052 | return 0; | |
788e7dd4 | 3053 | |
20dda18b SS |
3054 | if (sid == fsec->sid && fsec->isid == isec->sid && |
3055 | fsec->pseqno == avc_policy_seqno()) | |
83d49856 | 3056 | /* No change since file_open check. */ |
20dda18b SS |
3057 | return 0; |
3058 | ||
788e7dd4 YN |
3059 | return selinux_revalidate_file_permission(file, mask); |
3060 | } | |
3061 | ||
1da177e4 LT |
3062 | static int selinux_file_alloc_security(struct file *file) |
3063 | { | |
3064 | return file_alloc_security(file); | |
3065 | } | |
3066 | ||
3067 | static void selinux_file_free_security(struct file *file) | |
3068 | { | |
3069 | file_free_security(file); | |
3070 | } | |
3071 | ||
3072 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, | |
3073 | unsigned long arg) | |
3074 | { | |
88e67f3b | 3075 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3076 | int error = 0; |
1da177e4 | 3077 | |
0b24dcb7 EP |
3078 | switch (cmd) { |
3079 | case FIONREAD: | |
3080 | /* fall through */ | |
3081 | case FIBMAP: | |
3082 | /* fall through */ | |
3083 | case FIGETBSZ: | |
3084 | /* fall through */ | |
2f99c369 | 3085 | case FS_IOC_GETFLAGS: |
0b24dcb7 | 3086 | /* fall through */ |
2f99c369 | 3087 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3088 | error = file_has_perm(cred, file, FILE__GETATTR); |
3089 | break; | |
1da177e4 | 3090 | |
2f99c369 | 3091 | case FS_IOC_SETFLAGS: |
0b24dcb7 | 3092 | /* fall through */ |
2f99c369 | 3093 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3094 | error = file_has_perm(cred, file, FILE__SETATTR); |
3095 | break; | |
3096 | ||
3097 | /* sys_ioctl() checks */ | |
3098 | case FIONBIO: | |
3099 | /* fall through */ | |
3100 | case FIOASYNC: | |
3101 | error = file_has_perm(cred, file, 0); | |
3102 | break; | |
1da177e4 | 3103 | |
0b24dcb7 EP |
3104 | case KDSKBENT: |
3105 | case KDSKBSENT: | |
6a9de491 EP |
3106 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
3107 | SECURITY_CAP_AUDIT); | |
0b24dcb7 EP |
3108 | break; |
3109 | ||
3110 | /* default case assumes that the command will go | |
3111 | * to the file's ioctl() function. | |
3112 | */ | |
3113 | default: | |
3114 | error = file_has_perm(cred, file, FILE__IOCTL); | |
3115 | } | |
3116 | return error; | |
1da177e4 LT |
3117 | } |
3118 | ||
fcaaade1 SS |
3119 | static int default_noexec; |
3120 | ||
1da177e4 LT |
3121 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3122 | { | |
88e67f3b | 3123 | const struct cred *cred = current_cred(); |
d84f4f99 | 3124 | int rc = 0; |
88e67f3b | 3125 | |
fcaaade1 SS |
3126 | if (default_noexec && |
3127 | (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3128 | /* |
3129 | * We are making executable an anonymous mapping or a | |
3130 | * private file mapping that will also be writable. | |
3131 | * This has an additional check. | |
3132 | */ | |
d84f4f99 | 3133 | rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); |
1da177e4 | 3134 | if (rc) |
d84f4f99 | 3135 | goto error; |
1da177e4 | 3136 | } |
1da177e4 LT |
3137 | |
3138 | if (file) { | |
3139 | /* read access is always possible with a mapping */ | |
3140 | u32 av = FILE__READ; | |
3141 | ||
3142 | /* write access only matters if the mapping is shared */ | |
3143 | if (shared && (prot & PROT_WRITE)) | |
3144 | av |= FILE__WRITE; | |
3145 | ||
3146 | if (prot & PROT_EXEC) | |
3147 | av |= FILE__EXECUTE; | |
3148 | ||
88e67f3b | 3149 | return file_has_perm(cred, file, av); |
1da177e4 | 3150 | } |
d84f4f99 DH |
3151 | |
3152 | error: | |
3153 | return rc; | |
1da177e4 LT |
3154 | } |
3155 | ||
e5467859 | 3156 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3157 | { |
ed032189 | 3158 | int rc = 0; |
275bb41e | 3159 | u32 sid = current_sid(); |
1da177e4 | 3160 | |
84336d1a EP |
3161 | /* |
3162 | * notice that we are intentionally putting the SELinux check before | |
3163 | * the secondary cap_file_mmap check. This is such a likely attempt | |
3164 | * at bad behaviour/exploit that we always want to get the AVC, even | |
3165 | * if DAC would have also denied the operation. | |
3166 | */ | |
a2551df7 | 3167 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
ed032189 EP |
3168 | rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, |
3169 | MEMPROTECT__MMAP_ZERO, NULL); | |
84336d1a EP |
3170 | if (rc) |
3171 | return rc; | |
3172 | } | |
3173 | ||
3174 | /* do DAC check on address space usage */ | |
e5467859 AV |
3175 | return cap_mmap_addr(addr); |
3176 | } | |
1da177e4 | 3177 | |
e5467859 AV |
3178 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3179 | unsigned long prot, unsigned long flags) | |
3180 | { | |
1da177e4 LT |
3181 | if (selinux_checkreqprot) |
3182 | prot = reqprot; | |
3183 | ||
3184 | return file_map_prot_check(file, prot, | |
3185 | (flags & MAP_TYPE) == MAP_SHARED); | |
3186 | } | |
3187 | ||
3188 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3189 | unsigned long reqprot, | |
3190 | unsigned long prot) | |
3191 | { | |
88e67f3b | 3192 | const struct cred *cred = current_cred(); |
1da177e4 LT |
3193 | |
3194 | if (selinux_checkreqprot) | |
3195 | prot = reqprot; | |
3196 | ||
fcaaade1 SS |
3197 | if (default_noexec && |
3198 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3199 | int rc = 0; |
db4c9641 SS |
3200 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3201 | vma->vm_end <= vma->vm_mm->brk) { | |
d84f4f99 | 3202 | rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); |
db4c9641 SS |
3203 | } else if (!vma->vm_file && |
3204 | vma->vm_start <= vma->vm_mm->start_stack && | |
3205 | vma->vm_end >= vma->vm_mm->start_stack) { | |
3b11a1de | 3206 | rc = current_has_perm(current, PROCESS__EXECSTACK); |
db4c9641 SS |
3207 | } else if (vma->vm_file && vma->anon_vma) { |
3208 | /* | |
3209 | * We are making executable a file mapping that has | |
3210 | * had some COW done. Since pages might have been | |
3211 | * written, check ability to execute the possibly | |
3212 | * modified content. This typically should only | |
3213 | * occur for text relocations. | |
3214 | */ | |
d84f4f99 | 3215 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3216 | } |