]>
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 | |
102aefdd AA |
98 | #define SB_TYPE_FMT "%s%s%s" |
99 | #define SB_SUBTYPE(sb) (sb->s_subtype && sb->s_subtype[0]) | |
100 | #define SB_TYPE_ARGS(sb) sb->s_type->name, SB_SUBTYPE(sb) ? "." : "", SB_SUBTYPE(sb) ? sb->s_subtype : "" | |
c9180a57 | 101 | |
20510f2f | 102 | extern struct security_operations *security_ops; |
1da177e4 | 103 | |
d621d35e | 104 | /* SECMARK reference count */ |
56a4ca99 | 105 | static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); |
d621d35e | 106 | |
1da177e4 | 107 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
828dfe1d | 108 | int selinux_enforcing; |
1da177e4 LT |
109 | |
110 | static int __init enforcing_setup(char *str) | |
111 | { | |
f5269710 EP |
112 | unsigned long enforcing; |
113 | if (!strict_strtoul(str, 0, &enforcing)) | |
114 | selinux_enforcing = enforcing ? 1 : 0; | |
1da177e4 LT |
115 | return 1; |
116 | } | |
117 | __setup("enforcing=", enforcing_setup); | |
118 | #endif | |
119 | ||
120 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM | |
121 | int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; | |
122 | ||
123 | static int __init selinux_enabled_setup(char *str) | |
124 | { | |
f5269710 EP |
125 | unsigned long enabled; |
126 | if (!strict_strtoul(str, 0, &enabled)) | |
127 | selinux_enabled = enabled ? 1 : 0; | |
1da177e4 LT |
128 | return 1; |
129 | } | |
130 | __setup("selinux=", selinux_enabled_setup); | |
30d55280 SS |
131 | #else |
132 | int selinux_enabled = 1; | |
1da177e4 LT |
133 | #endif |
134 | ||
e18b890b | 135 | static struct kmem_cache *sel_inode_cache; |
7cae7e26 | 136 | |
d621d35e PM |
137 | /** |
138 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
139 | * | |
140 | * Description: | |
141 | * This function checks the SECMARK reference counter to see if any SECMARK | |
142 | * targets are currently configured, if the reference counter is greater than | |
143 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
2be4d74f CP |
144 | * enabled, false (0) if SECMARK is disabled. If the always_check_network |
145 | * policy capability is enabled, SECMARK is always considered enabled. | |
d621d35e PM |
146 | * |
147 | */ | |
148 | static int selinux_secmark_enabled(void) | |
149 | { | |
2be4d74f CP |
150 | return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount)); |
151 | } | |
152 | ||
153 | /** | |
154 | * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled | |
155 | * | |
156 | * Description: | |
157 | * This function checks if NetLabel or labeled IPSEC is enabled. Returns true | |
158 | * (1) if any are enabled or false (0) if neither are enabled. If the | |
159 | * always_check_network policy capability is enabled, peer labeling | |
160 | * is always considered enabled. | |
161 | * | |
162 | */ | |
163 | static int selinux_peerlbl_enabled(void) | |
164 | { | |
165 | return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled()); | |
d621d35e PM |
166 | } |
167 | ||
d84f4f99 DH |
168 | /* |
169 | * initialise the security for the init task | |
170 | */ | |
171 | static void cred_init_security(void) | |
1da177e4 | 172 | { |
3b11a1de | 173 | struct cred *cred = (struct cred *) current->real_cred; |
1da177e4 LT |
174 | struct task_security_struct *tsec; |
175 | ||
89d155ef | 176 | tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); |
1da177e4 | 177 | if (!tsec) |
d84f4f99 | 178 | panic("SELinux: Failed to initialize initial task.\n"); |
1da177e4 | 179 | |
d84f4f99 | 180 | tsec->osid = tsec->sid = SECINITSID_KERNEL; |
f1752eec | 181 | cred->security = tsec; |
1da177e4 LT |
182 | } |
183 | ||
88e67f3b DH |
184 | /* |
185 | * get the security ID of a set of credentials | |
186 | */ | |
187 | static inline u32 cred_sid(const struct cred *cred) | |
188 | { | |
189 | const struct task_security_struct *tsec; | |
190 | ||
191 | tsec = cred->security; | |
192 | return tsec->sid; | |
193 | } | |
194 | ||
275bb41e | 195 | /* |
3b11a1de | 196 | * get the objective security ID of a task |
275bb41e DH |
197 | */ |
198 | static inline u32 task_sid(const struct task_struct *task) | |
199 | { | |
275bb41e DH |
200 | u32 sid; |
201 | ||
202 | rcu_read_lock(); | |
88e67f3b | 203 | sid = cred_sid(__task_cred(task)); |
275bb41e DH |
204 | rcu_read_unlock(); |
205 | return sid; | |
206 | } | |
207 | ||
208 | /* | |
3b11a1de | 209 | * get the subjective security ID of the current task |
275bb41e DH |
210 | */ |
211 | static inline u32 current_sid(void) | |
212 | { | |
5fb49870 | 213 | const struct task_security_struct *tsec = current_security(); |
275bb41e DH |
214 | |
215 | return tsec->sid; | |
216 | } | |
217 | ||
88e67f3b DH |
218 | /* Allocate and free functions for each kind of security blob. */ |
219 | ||
1da177e4 LT |
220 | static int inode_alloc_security(struct inode *inode) |
221 | { | |
1da177e4 | 222 | struct inode_security_struct *isec; |
275bb41e | 223 | u32 sid = current_sid(); |
1da177e4 | 224 | |
a02fe132 | 225 | isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); |
1da177e4 LT |
226 | if (!isec) |
227 | return -ENOMEM; | |
228 | ||
23970741 | 229 | mutex_init(&isec->lock); |
1da177e4 | 230 | INIT_LIST_HEAD(&isec->list); |
1da177e4 LT |
231 | isec->inode = inode; |
232 | isec->sid = SECINITSID_UNLABELED; | |
233 | isec->sclass = SECCLASS_FILE; | |
275bb41e | 234 | isec->task_sid = sid; |
1da177e4 LT |
235 | inode->i_security = isec; |
236 | ||
237 | return 0; | |
238 | } | |
239 | ||
240 | static void inode_free_security(struct inode *inode) | |
241 | { | |
242 | struct inode_security_struct *isec = inode->i_security; | |
243 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
244 | ||
1da177e4 LT |
245 | spin_lock(&sbsec->isec_lock); |
246 | if (!list_empty(&isec->list)) | |
247 | list_del_init(&isec->list); | |
248 | spin_unlock(&sbsec->isec_lock); | |
249 | ||
250 | inode->i_security = NULL; | |
7cae7e26 | 251 | kmem_cache_free(sel_inode_cache, isec); |
1da177e4 LT |
252 | } |
253 | ||
254 | static int file_alloc_security(struct file *file) | |
255 | { | |
1da177e4 | 256 | struct file_security_struct *fsec; |
275bb41e | 257 | u32 sid = current_sid(); |
1da177e4 | 258 | |
26d2a4be | 259 | fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); |
1da177e4 LT |
260 | if (!fsec) |
261 | return -ENOMEM; | |
262 | ||
275bb41e DH |
263 | fsec->sid = sid; |
264 | fsec->fown_sid = sid; | |
1da177e4 LT |
265 | file->f_security = fsec; |
266 | ||
267 | return 0; | |
268 | } | |
269 | ||
270 | static void file_free_security(struct file *file) | |
271 | { | |
272 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 LT |
273 | file->f_security = NULL; |
274 | kfree(fsec); | |
275 | } | |
276 | ||
277 | static int superblock_alloc_security(struct super_block *sb) | |
278 | { | |
279 | struct superblock_security_struct *sbsec; | |
280 | ||
89d155ef | 281 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
282 | if (!sbsec) |
283 | return -ENOMEM; | |
284 | ||
bc7e982b | 285 | mutex_init(&sbsec->lock); |
1da177e4 LT |
286 | INIT_LIST_HEAD(&sbsec->isec_head); |
287 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
288 | sbsec->sb = sb; |
289 | sbsec->sid = SECINITSID_UNLABELED; | |
290 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 291 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
292 | sb->s_security = sbsec; |
293 | ||
294 | return 0; | |
295 | } | |
296 | ||
297 | static void superblock_free_security(struct super_block *sb) | |
298 | { | |
299 | struct superblock_security_struct *sbsec = sb->s_security; | |
1da177e4 LT |
300 | sb->s_security = NULL; |
301 | kfree(sbsec); | |
302 | } | |
303 | ||
1da177e4 LT |
304 | /* The file system's label must be initialized prior to use. */ |
305 | ||
eb9ae686 | 306 | static const char *labeling_behaviors[7] = { |
1da177e4 LT |
307 | "uses xattr", |
308 | "uses transition SIDs", | |
309 | "uses task SIDs", | |
310 | "uses genfs_contexts", | |
311 | "not configured for labeling", | |
312 | "uses mountpoint labeling", | |
eb9ae686 | 313 | "uses native labeling", |
1da177e4 LT |
314 | }; |
315 | ||
316 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); | |
317 | ||
318 | static inline int inode_doinit(struct inode *inode) | |
319 | { | |
320 | return inode_doinit_with_dentry(inode, NULL); | |
321 | } | |
322 | ||
323 | enum { | |
31e87930 | 324 | Opt_error = -1, |
1da177e4 LT |
325 | Opt_context = 1, |
326 | Opt_fscontext = 2, | |
c9180a57 EP |
327 | Opt_defcontext = 3, |
328 | Opt_rootcontext = 4, | |
11689d47 | 329 | Opt_labelsupport = 5, |
d355987f | 330 | Opt_nextmntopt = 6, |
1da177e4 LT |
331 | }; |
332 | ||
d355987f EP |
333 | #define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) |
334 | ||
a447c093 | 335 | static const match_table_t tokens = { |
832cbd9a EP |
336 | {Opt_context, CONTEXT_STR "%s"}, |
337 | {Opt_fscontext, FSCONTEXT_STR "%s"}, | |
338 | {Opt_defcontext, DEFCONTEXT_STR "%s"}, | |
339 | {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, | |
11689d47 | 340 | {Opt_labelsupport, LABELSUPP_STR}, |
31e87930 | 341 | {Opt_error, NULL}, |
1da177e4 LT |
342 | }; |
343 | ||
344 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
345 | ||
c312feb2 EP |
346 | static int may_context_mount_sb_relabel(u32 sid, |
347 | struct superblock_security_struct *sbsec, | |
275bb41e | 348 | const struct cred *cred) |
c312feb2 | 349 | { |
275bb41e | 350 | const struct task_security_struct *tsec = cred->security; |
c312feb2 EP |
351 | int rc; |
352 | ||
353 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
354 | FILESYSTEM__RELABELFROM, NULL); | |
355 | if (rc) | |
356 | return rc; | |
357 | ||
358 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, | |
359 | FILESYSTEM__RELABELTO, NULL); | |
360 | return rc; | |
361 | } | |
362 | ||
0808925e EP |
363 | static int may_context_mount_inode_relabel(u32 sid, |
364 | struct superblock_security_struct *sbsec, | |
275bb41e | 365 | const struct cred *cred) |
0808925e | 366 | { |
275bb41e | 367 | const struct task_security_struct *tsec = cred->security; |
0808925e EP |
368 | int rc; |
369 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
370 | FILESYSTEM__RELABELFROM, NULL); | |
371 | if (rc) | |
372 | return rc; | |
373 | ||
374 | rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
375 | FILESYSTEM__ASSOCIATE, NULL); | |
376 | return rc; | |
377 | } | |
378 | ||
b43e725d EP |
379 | static int selinux_is_sblabel_mnt(struct super_block *sb) |
380 | { | |
381 | struct superblock_security_struct *sbsec = sb->s_security; | |
382 | ||
383 | if (sbsec->behavior == SECURITY_FS_USE_XATTR || | |
384 | sbsec->behavior == SECURITY_FS_USE_TRANS || | |
385 | sbsec->behavior == SECURITY_FS_USE_TASK) | |
386 | return 1; | |
387 | ||
388 | /* Special handling for sysfs. Is genfs but also has setxattr handler*/ | |
389 | if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0) | |
390 | return 1; | |
391 | ||
392 | /* | |
393 | * Special handling for rootfs. Is genfs but supports | |
394 | * setting SELinux context on in-core inodes. | |
395 | */ | |
396 | if (strncmp(sb->s_type->name, "rootfs", sizeof("rootfs")) == 0) | |
397 | return 1; | |
398 | ||
399 | return 0; | |
400 | } | |
401 | ||
c9180a57 | 402 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 403 | { |
1da177e4 | 404 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 EP |
405 | struct dentry *root = sb->s_root; |
406 | struct inode *root_inode = root->d_inode; | |
407 | int rc = 0; | |
1da177e4 | 408 | |
c9180a57 EP |
409 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
410 | /* Make sure that the xattr handler exists and that no | |
411 | error other than -ENODATA is returned by getxattr on | |
412 | the root directory. -ENODATA is ok, as this may be | |
413 | the first boot of the SELinux kernel before we have | |
414 | assigned xattr values to the filesystem. */ | |
415 | if (!root_inode->i_op->getxattr) { | |
102aefdd AA |
416 | printk(KERN_WARNING "SELinux: (dev %s, type "SB_TYPE_FMT") has no " |
417 | "xattr support\n", sb->s_id, SB_TYPE_ARGS(sb)); | |
c9180a57 EP |
418 | rc = -EOPNOTSUPP; |
419 | goto out; | |
420 | } | |
421 | rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); | |
422 | if (rc < 0 && rc != -ENODATA) { | |
423 | if (rc == -EOPNOTSUPP) | |
424 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
102aefdd AA |
425 | SB_TYPE_FMT") has no security xattr handler\n", |
426 | sb->s_id, SB_TYPE_ARGS(sb)); | |
c9180a57 EP |
427 | else |
428 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
102aefdd AA |
429 | SB_TYPE_FMT") getxattr errno %d\n", sb->s_id, |
430 | SB_TYPE_ARGS(sb), -rc); | |
c9180a57 EP |
431 | goto out; |
432 | } | |
433 | } | |
1da177e4 | 434 | |
c9180a57 | 435 | if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) |
102aefdd AA |
436 | printk(KERN_ERR "SELinux: initialized (dev %s, type "SB_TYPE_FMT"), unknown behavior\n", |
437 | sb->s_id, SB_TYPE_ARGS(sb)); | |
c9180a57 | 438 | else |
102aefdd AA |
439 | printk(KERN_DEBUG "SELinux: initialized (dev %s, type "SB_TYPE_FMT"), %s\n", |
440 | sb->s_id, SB_TYPE_ARGS(sb), | |
c9180a57 | 441 | labeling_behaviors[sbsec->behavior-1]); |
1da177e4 | 442 | |
eadcabc6 | 443 | sbsec->flags |= SE_SBINITIALIZED; |
b43e725d | 444 | if (selinux_is_sblabel_mnt(sb)) |
12f348b9 | 445 | sbsec->flags |= SBLABEL_MNT; |
ddd29ec6 | 446 | |
c9180a57 EP |
447 | /* Initialize the root inode. */ |
448 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 449 | |
c9180a57 EP |
450 | /* Initialize any other inodes associated with the superblock, e.g. |
451 | inodes created prior to initial policy load or inodes created | |
452 | during get_sb by a pseudo filesystem that directly | |
453 | populates itself. */ | |
454 | spin_lock(&sbsec->isec_lock); | |
455 | next_inode: | |
456 | if (!list_empty(&sbsec->isec_head)) { | |
457 | struct inode_security_struct *isec = | |
458 | list_entry(sbsec->isec_head.next, | |
459 | struct inode_security_struct, list); | |
460 | struct inode *inode = isec->inode; | |
461 | spin_unlock(&sbsec->isec_lock); | |
462 | inode = igrab(inode); | |
463 | if (inode) { | |
464 | if (!IS_PRIVATE(inode)) | |
465 | inode_doinit(inode); | |
466 | iput(inode); | |
467 | } | |
468 | spin_lock(&sbsec->isec_lock); | |
469 | list_del_init(&isec->list); | |
470 | goto next_inode; | |
471 | } | |
472 | spin_unlock(&sbsec->isec_lock); | |
473 | out: | |
474 | return rc; | |
475 | } | |
1da177e4 | 476 | |
c9180a57 EP |
477 | /* |
478 | * This function should allow an FS to ask what it's mount security | |
479 | * options were so it can use those later for submounts, displaying | |
480 | * mount options, or whatever. | |
481 | */ | |
482 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
e0007529 | 483 | struct security_mnt_opts *opts) |
c9180a57 EP |
484 | { |
485 | int rc = 0, i; | |
486 | struct superblock_security_struct *sbsec = sb->s_security; | |
487 | char *context = NULL; | |
488 | u32 len; | |
489 | char tmp; | |
1da177e4 | 490 | |
e0007529 | 491 | security_init_mnt_opts(opts); |
1da177e4 | 492 | |
0d90a7ec | 493 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
c9180a57 | 494 | return -EINVAL; |
1da177e4 | 495 | |
c9180a57 EP |
496 | if (!ss_initialized) |
497 | return -EINVAL; | |
1da177e4 | 498 | |
af8e50cc EP |
499 | /* make sure we always check enough bits to cover the mask */ |
500 | BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); | |
501 | ||
0d90a7ec | 502 | tmp = sbsec->flags & SE_MNTMASK; |
c9180a57 | 503 | /* count the number of mount options for this sb */ |
af8e50cc | 504 | for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { |
c9180a57 | 505 | if (tmp & 0x01) |
e0007529 | 506 | opts->num_mnt_opts++; |
c9180a57 EP |
507 | tmp >>= 1; |
508 | } | |
11689d47 | 509 | /* Check if the Label support flag is set */ |
0b4bdb35 | 510 | if (sbsec->flags & SBLABEL_MNT) |
11689d47 | 511 | opts->num_mnt_opts++; |
1da177e4 | 512 | |
e0007529 EP |
513 | opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); |
514 | if (!opts->mnt_opts) { | |
c9180a57 EP |
515 | rc = -ENOMEM; |
516 | goto out_free; | |
517 | } | |
1da177e4 | 518 | |
e0007529 EP |
519 | opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); |
520 | if (!opts->mnt_opts_flags) { | |
c9180a57 EP |
521 | rc = -ENOMEM; |
522 | goto out_free; | |
523 | } | |
1da177e4 | 524 | |
c9180a57 EP |
525 | i = 0; |
526 | if (sbsec->flags & FSCONTEXT_MNT) { | |
527 | rc = security_sid_to_context(sbsec->sid, &context, &len); | |
528 | if (rc) | |
529 | goto out_free; | |
e0007529 EP |
530 | opts->mnt_opts[i] = context; |
531 | opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; | |
c9180a57 EP |
532 | } |
533 | if (sbsec->flags & CONTEXT_MNT) { | |
534 | rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); | |
535 | if (rc) | |
536 | goto out_free; | |
e0007529 EP |
537 | opts->mnt_opts[i] = context; |
538 | opts->mnt_opts_flags[i++] = CONTEXT_MNT; | |
c9180a57 EP |
539 | } |
540 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
541 | rc = security_sid_to_context(sbsec->def_sid, &context, &len); | |
542 | if (rc) | |
543 | goto out_free; | |
e0007529 EP |
544 | opts->mnt_opts[i] = context; |
545 | opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
546 | } |
547 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
548 | struct inode *root = sbsec->sb->s_root->d_inode; | |
549 | struct inode_security_struct *isec = root->i_security; | |
0808925e | 550 | |
c9180a57 EP |
551 | rc = security_sid_to_context(isec->sid, &context, &len); |
552 | if (rc) | |
553 | goto out_free; | |
e0007529 EP |
554 | opts->mnt_opts[i] = context; |
555 | opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; | |
c9180a57 | 556 | } |
12f348b9 | 557 | if (sbsec->flags & SBLABEL_MNT) { |
11689d47 | 558 | opts->mnt_opts[i] = NULL; |
12f348b9 | 559 | opts->mnt_opts_flags[i++] = SBLABEL_MNT; |
11689d47 | 560 | } |
1da177e4 | 561 | |
e0007529 | 562 | BUG_ON(i != opts->num_mnt_opts); |
1da177e4 | 563 | |
c9180a57 EP |
564 | return 0; |
565 | ||
566 | out_free: | |
e0007529 | 567 | security_free_mnt_opts(opts); |
c9180a57 EP |
568 | return rc; |
569 | } | |
1da177e4 | 570 | |
c9180a57 EP |
571 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
572 | u32 old_sid, u32 new_sid) | |
573 | { | |
0d90a7ec DQ |
574 | char mnt_flags = sbsec->flags & SE_MNTMASK; |
575 | ||
c9180a57 | 576 | /* check if the old mount command had the same options */ |
0d90a7ec | 577 | if (sbsec->flags & SE_SBINITIALIZED) |
c9180a57 EP |
578 | if (!(sbsec->flags & flag) || |
579 | (old_sid != new_sid)) | |
580 | return 1; | |
581 | ||
582 | /* check if we were passed the same options twice, | |
583 | * aka someone passed context=a,context=b | |
584 | */ | |
0d90a7ec DQ |
585 | if (!(sbsec->flags & SE_SBINITIALIZED)) |
586 | if (mnt_flags & flag) | |
c9180a57 EP |
587 | return 1; |
588 | return 0; | |
589 | } | |
e0007529 | 590 | |
c9180a57 EP |
591 | /* |
592 | * Allow filesystems with binary mount data to explicitly set mount point | |
593 | * labeling information. | |
594 | */ | |
e0007529 | 595 | static int selinux_set_mnt_opts(struct super_block *sb, |
649f6e77 DQ |
596 | struct security_mnt_opts *opts, |
597 | unsigned long kern_flags, | |
598 | unsigned long *set_kern_flags) | |
c9180a57 | 599 | { |
275bb41e | 600 | const struct cred *cred = current_cred(); |
c9180a57 | 601 | int rc = 0, i; |
c9180a57 | 602 | struct superblock_security_struct *sbsec = sb->s_security; |
089be43e JM |
603 | struct inode *inode = sbsec->sb->s_root->d_inode; |
604 | struct inode_security_struct *root_isec = inode->i_security; | |
c9180a57 EP |
605 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
606 | u32 defcontext_sid = 0; | |
e0007529 EP |
607 | char **mount_options = opts->mnt_opts; |
608 | int *flags = opts->mnt_opts_flags; | |
609 | int num_opts = opts->num_mnt_opts; | |
c9180a57 EP |
610 | |
611 | mutex_lock(&sbsec->lock); | |
612 | ||
613 | if (!ss_initialized) { | |
614 | if (!num_opts) { | |
615 | /* Defer initialization until selinux_complete_init, | |
616 | after the initial policy is loaded and the security | |
617 | server is ready to handle calls. */ | |
c9180a57 EP |
618 | goto out; |
619 | } | |
620 | rc = -EINVAL; | |
744ba35e EP |
621 | printk(KERN_WARNING "SELinux: Unable to set superblock options " |
622 | "before the security server is initialized\n"); | |
1da177e4 | 623 | goto out; |
c9180a57 | 624 | } |
649f6e77 DQ |
625 | if (kern_flags && !set_kern_flags) { |
626 | /* Specifying internal flags without providing a place to | |
627 | * place the results is not allowed */ | |
628 | rc = -EINVAL; | |
629 | goto out; | |
630 | } | |
1da177e4 | 631 | |
e0007529 EP |
632 | /* |
633 | * Binary mount data FS will come through this function twice. Once | |
634 | * from an explicit call and once from the generic calls from the vfs. | |
635 | * Since the generic VFS calls will not contain any security mount data | |
636 | * we need to skip the double mount verification. | |
637 | * | |
638 | * This does open a hole in which we will not notice if the first | |
639 | * mount using this sb set explict options and a second mount using | |
640 | * this sb does not set any security options. (The first options | |
641 | * will be used for both mounts) | |
642 | */ | |
0d90a7ec | 643 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) |
e0007529 | 644 | && (num_opts == 0)) |
f5269710 | 645 | goto out; |
e0007529 | 646 | |
c9180a57 EP |
647 | /* |
648 | * parse the mount options, check if they are valid sids. | |
649 | * also check if someone is trying to mount the same sb more | |
650 | * than once with different security options. | |
651 | */ | |
652 | for (i = 0; i < num_opts; i++) { | |
653 | u32 sid; | |
11689d47 | 654 | |
12f348b9 | 655 | if (flags[i] == SBLABEL_MNT) |
11689d47 | 656 | continue; |
c9180a57 EP |
657 | rc = security_context_to_sid(mount_options[i], |
658 | strlen(mount_options[i]), &sid); | |
1da177e4 LT |
659 | if (rc) { |
660 | printk(KERN_WARNING "SELinux: security_context_to_sid" | |
102aefdd AA |
661 | "(%s) failed for (dev %s, type "SB_TYPE_FMT") errno=%d\n", |
662 | mount_options[i], sb->s_id, SB_TYPE_ARGS(sb), rc); | |
c9180a57 EP |
663 | goto out; |
664 | } | |
665 | switch (flags[i]) { | |
666 | case FSCONTEXT_MNT: | |
667 | fscontext_sid = sid; | |
668 | ||
669 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
670 | fscontext_sid)) | |
671 | goto out_double_mount; | |
672 | ||
673 | sbsec->flags |= FSCONTEXT_MNT; | |
674 | break; | |
675 | case CONTEXT_MNT: | |
676 | context_sid = sid; | |
677 | ||
678 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
679 | context_sid)) | |
680 | goto out_double_mount; | |
681 | ||
682 | sbsec->flags |= CONTEXT_MNT; | |
683 | break; | |
684 | case ROOTCONTEXT_MNT: | |
685 | rootcontext_sid = sid; | |
686 | ||
687 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
688 | rootcontext_sid)) | |
689 | goto out_double_mount; | |
690 | ||
691 | sbsec->flags |= ROOTCONTEXT_MNT; | |
692 | ||
693 | break; | |
694 | case DEFCONTEXT_MNT: | |
695 | defcontext_sid = sid; | |
696 | ||
697 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
698 | defcontext_sid)) | |
699 | goto out_double_mount; | |
700 | ||
701 | sbsec->flags |= DEFCONTEXT_MNT; | |
702 | ||
703 | break; | |
704 | default: | |
705 | rc = -EINVAL; | |
706 | goto out; | |
1da177e4 | 707 | } |
c9180a57 EP |
708 | } |
709 | ||
0d90a7ec | 710 | if (sbsec->flags & SE_SBINITIALIZED) { |
c9180a57 | 711 | /* previously mounted with options, but not on this attempt? */ |
0d90a7ec | 712 | if ((sbsec->flags & SE_MNTMASK) && !num_opts) |
c9180a57 EP |
713 | goto out_double_mount; |
714 | rc = 0; | |
715 | goto out; | |
716 | } | |
717 | ||
089be43e | 718 | if (strcmp(sb->s_type->name, "proc") == 0) |
0d90a7ec | 719 | sbsec->flags |= SE_SBPROC; |
c9180a57 | 720 | |
eb9ae686 DQ |
721 | if (!sbsec->behavior) { |
722 | /* | |
723 | * Determine the labeling behavior to use for this | |
724 | * filesystem type. | |
725 | */ | |
98f700f3 | 726 | rc = security_fs_use(sb); |
eb9ae686 DQ |
727 | if (rc) { |
728 | printk(KERN_WARNING | |
729 | "%s: security_fs_use(%s) returned %d\n", | |
730 | __func__, sb->s_type->name, rc); | |
731 | goto out; | |
732 | } | |
c9180a57 | 733 | } |
c9180a57 EP |
734 | /* sets the context of the superblock for the fs being mounted. */ |
735 | if (fscontext_sid) { | |
275bb41e | 736 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); |
1da177e4 | 737 | if (rc) |
c9180a57 | 738 | goto out; |
1da177e4 | 739 | |
c9180a57 | 740 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
741 | } |
742 | ||
743 | /* | |
744 | * Switch to using mount point labeling behavior. | |
745 | * sets the label used on all file below the mountpoint, and will set | |
746 | * the superblock context if not already set. | |
747 | */ | |
eb9ae686 DQ |
748 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { |
749 | sbsec->behavior = SECURITY_FS_USE_NATIVE; | |
750 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
751 | } | |
752 | ||
c9180a57 EP |
753 | if (context_sid) { |
754 | if (!fscontext_sid) { | |
275bb41e DH |
755 | rc = may_context_mount_sb_relabel(context_sid, sbsec, |
756 | cred); | |
b04ea3ce | 757 | if (rc) |
c9180a57 EP |
758 | goto out; |
759 | sbsec->sid = context_sid; | |
b04ea3ce | 760 | } else { |
275bb41e DH |
761 | rc = may_context_mount_inode_relabel(context_sid, sbsec, |
762 | cred); | |
b04ea3ce | 763 | if (rc) |
c9180a57 | 764 | goto out; |
b04ea3ce | 765 | } |
c9180a57 EP |
766 | if (!rootcontext_sid) |
767 | rootcontext_sid = context_sid; | |
1da177e4 | 768 | |
c9180a57 | 769 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 770 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
771 | } |
772 | ||
c9180a57 | 773 | if (rootcontext_sid) { |
275bb41e DH |
774 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, |
775 | cred); | |
0808925e | 776 | if (rc) |
c9180a57 | 777 | goto out; |
0808925e | 778 | |
c9180a57 EP |
779 | root_isec->sid = rootcontext_sid; |
780 | root_isec->initialized = 1; | |
0808925e EP |
781 | } |
782 | ||
c9180a57 | 783 | if (defcontext_sid) { |
eb9ae686 DQ |
784 | if (sbsec->behavior != SECURITY_FS_USE_XATTR && |
785 | sbsec->behavior != SECURITY_FS_USE_NATIVE) { | |
c9180a57 EP |
786 | rc = -EINVAL; |
787 | printk(KERN_WARNING "SELinux: defcontext option is " | |
788 | "invalid for this filesystem type\n"); | |
789 | goto out; | |
1da177e4 LT |
790 | } |
791 | ||
c9180a57 EP |
792 | if (defcontext_sid != sbsec->def_sid) { |
793 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
275bb41e | 794 | sbsec, cred); |
c9180a57 EP |
795 | if (rc) |
796 | goto out; | |
797 | } | |
1da177e4 | 798 | |
c9180a57 | 799 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
800 | } |
801 | ||
c9180a57 | 802 | rc = sb_finish_set_opts(sb); |
1da177e4 | 803 | out: |
c9180a57 | 804 | mutex_unlock(&sbsec->lock); |
1da177e4 | 805 | return rc; |
c9180a57 EP |
806 | out_double_mount: |
807 | rc = -EINVAL; | |
808 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " | |
102aefdd AA |
809 | "security settings for (dev %s, type "SB_TYPE_FMT")\n", sb->s_id, |
810 | SB_TYPE_ARGS(sb)); | |
c9180a57 | 811 | goto out; |
1da177e4 LT |
812 | } |
813 | ||
094f7b69 JL |
814 | static int selinux_cmp_sb_context(const struct super_block *oldsb, |
815 | const struct super_block *newsb) | |
816 | { | |
817 | struct superblock_security_struct *old = oldsb->s_security; | |
818 | struct superblock_security_struct *new = newsb->s_security; | |
819 | char oldflags = old->flags & SE_MNTMASK; | |
820 | char newflags = new->flags & SE_MNTMASK; | |
821 | ||
822 | if (oldflags != newflags) | |
823 | goto mismatch; | |
824 | if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) | |
825 | goto mismatch; | |
826 | if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) | |
827 | goto mismatch; | |
828 | if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) | |
829 | goto mismatch; | |
830 | if (oldflags & ROOTCONTEXT_MNT) { | |
831 | struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security; | |
832 | struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security; | |
833 | if (oldroot->sid != newroot->sid) | |
834 | goto mismatch; | |
835 | } | |
836 | return 0; | |
837 | mismatch: | |
838 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " | |
839 | "different security settings for (dev %s, " | |
840 | "type %s)\n", newsb->s_id, newsb->s_type->name); | |
841 | return -EBUSY; | |
842 | } | |
843 | ||
844 | static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, | |
c9180a57 | 845 | struct super_block *newsb) |
1da177e4 | 846 | { |
c9180a57 EP |
847 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
848 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 849 | |
c9180a57 EP |
850 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
851 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
852 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 853 | |
0f5e6420 EP |
854 | /* |
855 | * if the parent was able to be mounted it clearly had no special lsm | |
e8c26255 | 856 | * mount options. thus we can safely deal with this superblock later |
0f5e6420 | 857 | */ |
e8c26255 | 858 | if (!ss_initialized) |
094f7b69 | 859 | return 0; |
c9180a57 | 860 | |
c9180a57 | 861 | /* how can we clone if the old one wasn't set up?? */ |
0d90a7ec | 862 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); |
c9180a57 | 863 | |
094f7b69 | 864 | /* if fs is reusing a sb, make sure that the contexts match */ |
0d90a7ec | 865 | if (newsbsec->flags & SE_SBINITIALIZED) |
094f7b69 | 866 | return selinux_cmp_sb_context(oldsb, newsb); |
5a552617 | 867 | |
c9180a57 EP |
868 | mutex_lock(&newsbsec->lock); |
869 | ||
870 | newsbsec->flags = oldsbsec->flags; | |
871 | ||
872 | newsbsec->sid = oldsbsec->sid; | |
873 | newsbsec->def_sid = oldsbsec->def_sid; | |
874 | newsbsec->behavior = oldsbsec->behavior; | |
875 | ||
876 | if (set_context) { | |
877 | u32 sid = oldsbsec->mntpoint_sid; | |
878 | ||
879 | if (!set_fscontext) | |
880 | newsbsec->sid = sid; | |
881 | if (!set_rootcontext) { | |
882 | struct inode *newinode = newsb->s_root->d_inode; | |
883 | struct inode_security_struct *newisec = newinode->i_security; | |
884 | newisec->sid = sid; | |
885 | } | |
886 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 887 | } |
c9180a57 EP |
888 | if (set_rootcontext) { |
889 | const struct inode *oldinode = oldsb->s_root->d_inode; | |
890 | const struct inode_security_struct *oldisec = oldinode->i_security; | |
891 | struct inode *newinode = newsb->s_root->d_inode; | |
892 | struct inode_security_struct *newisec = newinode->i_security; | |
1da177e4 | 893 | |
c9180a57 | 894 | newisec->sid = oldisec->sid; |
1da177e4 LT |
895 | } |
896 | ||
c9180a57 EP |
897 | sb_finish_set_opts(newsb); |
898 | mutex_unlock(&newsbsec->lock); | |
094f7b69 | 899 | return 0; |
c9180a57 EP |
900 | } |
901 | ||
2e1479d9 AB |
902 | static int selinux_parse_opts_str(char *options, |
903 | struct security_mnt_opts *opts) | |
c9180a57 | 904 | { |
e0007529 | 905 | char *p; |
c9180a57 EP |
906 | char *context = NULL, *defcontext = NULL; |
907 | char *fscontext = NULL, *rootcontext = NULL; | |
e0007529 | 908 | int rc, num_mnt_opts = 0; |
1da177e4 | 909 | |
e0007529 | 910 | opts->num_mnt_opts = 0; |
1da177e4 | 911 | |
c9180a57 EP |
912 | /* Standard string-based options. */ |
913 | while ((p = strsep(&options, "|")) != NULL) { | |
914 | int token; | |
915 | substring_t args[MAX_OPT_ARGS]; | |
1da177e4 | 916 | |
c9180a57 EP |
917 | if (!*p) |
918 | continue; | |
1da177e4 | 919 | |
c9180a57 | 920 | token = match_token(p, tokens, args); |
1da177e4 | 921 | |
c9180a57 EP |
922 | switch (token) { |
923 | case Opt_context: | |
924 | if (context || defcontext) { | |
925 | rc = -EINVAL; | |
926 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
927 | goto out_err; | |
928 | } | |
929 | context = match_strdup(&args[0]); | |
930 | if (!context) { | |
931 | rc = -ENOMEM; | |
932 | goto out_err; | |
933 | } | |
934 | break; | |
935 | ||
936 | case Opt_fscontext: | |
937 | if (fscontext) { | |
938 | rc = -EINVAL; | |
939 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
940 | goto out_err; | |
941 | } | |
942 | fscontext = match_strdup(&args[0]); | |
943 | if (!fscontext) { | |
944 | rc = -ENOMEM; | |
945 | goto out_err; | |
946 | } | |
947 | break; | |
948 | ||
949 | case Opt_rootcontext: | |
950 | if (rootcontext) { | |
951 | rc = -EINVAL; | |
952 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
953 | goto out_err; | |
954 | } | |
955 | rootcontext = match_strdup(&args[0]); | |
956 | if (!rootcontext) { | |
957 | rc = -ENOMEM; | |
958 | goto out_err; | |
959 | } | |
960 | break; | |
961 | ||
962 | case Opt_defcontext: | |
963 | if (context || defcontext) { | |
964 | rc = -EINVAL; | |
965 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
966 | goto out_err; | |
967 | } | |
968 | defcontext = match_strdup(&args[0]); | |
969 | if (!defcontext) { | |
970 | rc = -ENOMEM; | |
971 | goto out_err; | |
972 | } | |
973 | break; | |
11689d47 DQ |
974 | case Opt_labelsupport: |
975 | break; | |
c9180a57 EP |
976 | default: |
977 | rc = -EINVAL; | |
978 | printk(KERN_WARNING "SELinux: unknown mount option\n"); | |
979 | goto out_err; | |
1da177e4 | 980 | |
1da177e4 | 981 | } |
1da177e4 | 982 | } |
c9180a57 | 983 | |
e0007529 EP |
984 | rc = -ENOMEM; |
985 | opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); | |
986 | if (!opts->mnt_opts) | |
987 | goto out_err; | |
988 | ||
989 | opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); | |
990 | if (!opts->mnt_opts_flags) { | |
991 | kfree(opts->mnt_opts); | |
992 | goto out_err; | |
993 | } | |
994 | ||
c9180a57 | 995 | if (fscontext) { |
e0007529 EP |
996 | opts->mnt_opts[num_mnt_opts] = fscontext; |
997 | opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; | |
c9180a57 EP |
998 | } |
999 | if (context) { | |
e0007529 EP |
1000 | opts->mnt_opts[num_mnt_opts] = context; |
1001 | opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; | |
c9180a57 EP |
1002 | } |
1003 | if (rootcontext) { | |
e0007529 EP |
1004 | opts->mnt_opts[num_mnt_opts] = rootcontext; |
1005 | opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; | |
c9180a57 EP |
1006 | } |
1007 | if (defcontext) { | |
e0007529 EP |
1008 | opts->mnt_opts[num_mnt_opts] = defcontext; |
1009 | opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
1010 | } |
1011 | ||
e0007529 EP |
1012 | opts->num_mnt_opts = num_mnt_opts; |
1013 | return 0; | |
1014 | ||
c9180a57 EP |
1015 | out_err: |
1016 | kfree(context); | |
1017 | kfree(defcontext); | |
1018 | kfree(fscontext); | |
1019 | kfree(rootcontext); | |
1da177e4 LT |
1020 | return rc; |
1021 | } | |
e0007529 EP |
1022 | /* |
1023 | * string mount options parsing and call set the sbsec | |
1024 | */ | |
1025 | static int superblock_doinit(struct super_block *sb, void *data) | |
1026 | { | |
1027 | int rc = 0; | |
1028 | char *options = data; | |
1029 | struct security_mnt_opts opts; | |
1030 | ||
1031 | security_init_mnt_opts(&opts); | |
1032 | ||
1033 | if (!data) | |
1034 | goto out; | |
1035 | ||
1036 | BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); | |
1037 | ||
1038 | rc = selinux_parse_opts_str(options, &opts); | |
1039 | if (rc) | |
1040 | goto out_err; | |
1041 | ||
1042 | out: | |
649f6e77 | 1043 | rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); |
e0007529 EP |
1044 | |
1045 | out_err: | |
1046 | security_free_mnt_opts(&opts); | |
1047 | return rc; | |
1048 | } | |
1da177e4 | 1049 | |
3583a711 AB |
1050 | static void selinux_write_opts(struct seq_file *m, |
1051 | struct security_mnt_opts *opts) | |
2069f457 EP |
1052 | { |
1053 | int i; | |
1054 | char *prefix; | |
1055 | ||
1056 | for (i = 0; i < opts->num_mnt_opts; i++) { | |
11689d47 DQ |
1057 | char *has_comma; |
1058 | ||
1059 | if (opts->mnt_opts[i]) | |
1060 | has_comma = strchr(opts->mnt_opts[i], ','); | |
1061 | else | |
1062 | has_comma = NULL; | |
2069f457 EP |
1063 | |
1064 | switch (opts->mnt_opts_flags[i]) { | |
1065 | case CONTEXT_MNT: | |
1066 | prefix = CONTEXT_STR; | |
1067 | break; | |
1068 | case FSCONTEXT_MNT: | |
1069 | prefix = FSCONTEXT_STR; | |
1070 | break; | |
1071 | case ROOTCONTEXT_MNT: | |
1072 | prefix = ROOTCONTEXT_STR; | |
1073 | break; | |
1074 | case DEFCONTEXT_MNT: | |
1075 | prefix = DEFCONTEXT_STR; | |
1076 | break; | |
12f348b9 | 1077 | case SBLABEL_MNT: |
11689d47 DQ |
1078 | seq_putc(m, ','); |
1079 | seq_puts(m, LABELSUPP_STR); | |
1080 | continue; | |
2069f457 EP |
1081 | default: |
1082 | BUG(); | |
a35c6c83 | 1083 | return; |
2069f457 EP |
1084 | }; |
1085 | /* we need a comma before each option */ | |
1086 | seq_putc(m, ','); | |
1087 | seq_puts(m, prefix); | |
1088 | if (has_comma) | |
1089 | seq_putc(m, '\"'); | |
1090 | seq_puts(m, opts->mnt_opts[i]); | |
1091 | if (has_comma) | |
1092 | seq_putc(m, '\"'); | |
1093 | } | |
1094 | } | |
1095 | ||
1096 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1097 | { | |
1098 | struct security_mnt_opts opts; | |
1099 | int rc; | |
1100 | ||
1101 | rc = selinux_get_mnt_opts(sb, &opts); | |
383795c2 EP |
1102 | if (rc) { |
1103 | /* before policy load we may get EINVAL, don't show anything */ | |
1104 | if (rc == -EINVAL) | |
1105 | rc = 0; | |
2069f457 | 1106 | return rc; |
383795c2 | 1107 | } |
2069f457 EP |
1108 | |
1109 | selinux_write_opts(m, &opts); | |
1110 | ||
1111 | security_free_mnt_opts(&opts); | |
1112 | ||
1113 | return rc; | |
1114 | } | |
1115 | ||
1da177e4 LT |
1116 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1117 | { | |
1118 | switch (mode & S_IFMT) { | |
1119 | case S_IFSOCK: | |
1120 | return SECCLASS_SOCK_FILE; | |
1121 | case S_IFLNK: | |
1122 | return SECCLASS_LNK_FILE; | |
1123 | case S_IFREG: | |
1124 | return SECCLASS_FILE; | |
1125 | case S_IFBLK: | |
1126 | return SECCLASS_BLK_FILE; | |
1127 | case S_IFDIR: | |
1128 | return SECCLASS_DIR; | |
1129 | case S_IFCHR: | |
1130 | return SECCLASS_CHR_FILE; | |
1131 | case S_IFIFO: | |
1132 | return SECCLASS_FIFO_FILE; | |
1133 | ||
1134 | } | |
1135 | ||
1136 | return SECCLASS_FILE; | |
1137 | } | |
1138 | ||
13402580 JM |
1139 | static inline int default_protocol_stream(int protocol) |
1140 | { | |
1141 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1142 | } | |
1143 | ||
1144 | static inline int default_protocol_dgram(int protocol) | |
1145 | { | |
1146 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1147 | } | |
1148 | ||
1da177e4 LT |
1149 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1150 | { | |
1151 | switch (family) { | |
1152 | case PF_UNIX: | |
1153 | switch (type) { | |
1154 | case SOCK_STREAM: | |
1155 | case SOCK_SEQPACKET: | |
1156 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1157 | case SOCK_DGRAM: | |
1158 | return SECCLASS_UNIX_DGRAM_SOCKET; | |
1159 | } | |
1160 | break; | |
1161 | case PF_INET: | |
1162 | case PF_INET6: | |
1163 | switch (type) { | |
1164 | case SOCK_STREAM: | |
13402580 JM |
1165 | if (default_protocol_stream(protocol)) |
1166 | return SECCLASS_TCP_SOCKET; | |
1167 | else | |
1168 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1169 | case SOCK_DGRAM: |
13402580 JM |
1170 | if (default_protocol_dgram(protocol)) |
1171 | return SECCLASS_UDP_SOCKET; | |
1172 | else | |
1173 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1174 | case SOCK_DCCP: |
1175 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1176 | default: |
1da177e4 LT |
1177 | return SECCLASS_RAWIP_SOCKET; |
1178 | } | |
1179 | break; | |
1180 | case PF_NETLINK: | |
1181 | switch (protocol) { | |
1182 | case NETLINK_ROUTE: | |
1183 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
1184 | case NETLINK_FIREWALL: | |
1185 | return SECCLASS_NETLINK_FIREWALL_SOCKET; | |
7f1fb60c | 1186 | case NETLINK_SOCK_DIAG: |
1da177e4 LT |
1187 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1188 | case NETLINK_NFLOG: | |
1189 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1190 | case NETLINK_XFRM: | |
1191 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1192 | case NETLINK_SELINUX: | |
1193 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
1194 | case NETLINK_AUDIT: | |
1195 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
1196 | case NETLINK_IP6_FW: | |
1197 | return SECCLASS_NETLINK_IP6FW_SOCKET; | |
1198 | case NETLINK_DNRTMSG: | |
1199 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1200 | case NETLINK_KOBJECT_UEVENT: |
1201 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
1da177e4 LT |
1202 | default: |
1203 | return SECCLASS_NETLINK_SOCKET; | |
1204 | } | |
1205 | case PF_PACKET: | |
1206 | return SECCLASS_PACKET_SOCKET; | |
1207 | case PF_KEY: | |
1208 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1209 | case PF_APPLETALK: |
1210 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1211 | } |
1212 | ||
1213 | return SECCLASS_SOCKET; | |
1214 | } | |
1215 | ||
1216 | #ifdef CONFIG_PROC_FS | |
8e6c9693 | 1217 | static int selinux_proc_get_sid(struct dentry *dentry, |
1da177e4 LT |
1218 | u16 tclass, |
1219 | u32 *sid) | |
1220 | { | |
8e6c9693 LAG |
1221 | int rc; |
1222 | char *buffer, *path; | |
1da177e4 | 1223 | |
828dfe1d | 1224 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1225 | if (!buffer) |
1226 | return -ENOMEM; | |
1227 | ||
8e6c9693 LAG |
1228 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); |
1229 | if (IS_ERR(path)) | |
1230 | rc = PTR_ERR(path); | |
1231 | else { | |
1232 | /* each process gets a /proc/PID/ entry. Strip off the | |
1233 | * PID part to get a valid selinux labeling. | |
1234 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1235 | while (path[1] >= '0' && path[1] <= '9') { | |
1236 | path[1] = '/'; | |
1237 | path++; | |
1238 | } | |
1239 | rc = security_genfs_sid("proc", path, tclass, sid); | |
1da177e4 | 1240 | } |
1da177e4 LT |
1241 | free_page((unsigned long)buffer); |
1242 | return rc; | |
1243 | } | |
1244 | #else | |
8e6c9693 | 1245 | static int selinux_proc_get_sid(struct dentry *dentry, |
1da177e4 LT |
1246 | u16 tclass, |
1247 | u32 *sid) | |
1248 | { | |
1249 | return -EINVAL; | |
1250 | } | |
1251 | #endif | |
1252 | ||
1253 | /* The inode's security attributes must be initialized before first use. */ | |
1254 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1255 | { | |
1256 | struct superblock_security_struct *sbsec = NULL; | |
1257 | struct inode_security_struct *isec = inode->i_security; | |
1258 | u32 sid; | |
1259 | struct dentry *dentry; | |
1260 | #define INITCONTEXTLEN 255 | |
1261 | char *context = NULL; | |
1262 | unsigned len = 0; | |
1263 | int rc = 0; | |
1da177e4 LT |
1264 | |
1265 | if (isec->initialized) | |
1266 | goto out; | |
1267 | ||
23970741 | 1268 | mutex_lock(&isec->lock); |
1da177e4 | 1269 | if (isec->initialized) |
23970741 | 1270 | goto out_unlock; |
1da177e4 LT |
1271 | |
1272 | sbsec = inode->i_sb->s_security; | |
0d90a7ec | 1273 | if (!(sbsec->flags & SE_SBINITIALIZED)) { |
1da177e4 LT |
1274 | /* Defer initialization until selinux_complete_init, |
1275 | after the initial policy is loaded and the security | |
1276 | server is ready to handle calls. */ | |
1277 | spin_lock(&sbsec->isec_lock); | |
1278 | if (list_empty(&isec->list)) | |
1279 | list_add(&isec->list, &sbsec->isec_head); | |
1280 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1281 | goto out_unlock; |
1da177e4 LT |
1282 | } |
1283 | ||
1284 | switch (sbsec->behavior) { | |
eb9ae686 DQ |
1285 | case SECURITY_FS_USE_NATIVE: |
1286 | break; | |
1da177e4 LT |
1287 | case SECURITY_FS_USE_XATTR: |
1288 | if (!inode->i_op->getxattr) { | |
1289 | isec->sid = sbsec->def_sid; | |
1290 | break; | |
1291 | } | |
1292 | ||
1293 | /* Need a dentry, since the xattr API requires one. | |
1294 | Life would be simpler if we could just pass the inode. */ | |
1295 | if (opt_dentry) { | |
1296 | /* Called from d_instantiate or d_splice_alias. */ | |
1297 | dentry = dget(opt_dentry); | |
1298 | } else { | |
1299 | /* Called from selinux_complete_init, try to find a dentry. */ | |
1300 | dentry = d_find_alias(inode); | |
1301 | } | |
1302 | if (!dentry) { | |
df7f54c0 EP |
1303 | /* |
1304 | * this is can be hit on boot when a file is accessed | |
1305 | * before the policy is loaded. When we load policy we | |
1306 | * may find inodes that have no dentry on the | |
1307 | * sbsec->isec_head list. No reason to complain as these | |
1308 | * will get fixed up the next time we go through | |
1309 | * inode_doinit with a dentry, before these inodes could | |
1310 | * be used again by userspace. | |
1311 | */ | |
23970741 | 1312 | goto out_unlock; |
1da177e4 LT |
1313 | } |
1314 | ||
1315 | len = INITCONTEXTLEN; | |
4cb912f1 | 1316 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1317 | if (!context) { |
1318 | rc = -ENOMEM; | |
1319 | dput(dentry); | |
23970741 | 1320 | goto out_unlock; |
1da177e4 | 1321 | } |
4cb912f1 | 1322 | context[len] = '\0'; |
1da177e4 LT |
1323 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, |
1324 | context, len); | |
1325 | if (rc == -ERANGE) { | |
314dabb8 JM |
1326 | kfree(context); |
1327 | ||
1da177e4 LT |
1328 | /* Need a larger buffer. Query for the right size. */ |
1329 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, | |
1330 | NULL, 0); | |
1331 | if (rc < 0) { | |
1332 | dput(dentry); | |
23970741 | 1333 | goto out_unlock; |
1da177e4 | 1334 | } |
1da177e4 | 1335 | len = rc; |
4cb912f1 | 1336 | context = kmalloc(len+1, GFP_NOFS); |
1da177e4 LT |
1337 | if (!context) { |
1338 | rc = -ENOMEM; | |
1339 | dput(dentry); | |
23970741 | 1340 | goto out_unlock; |
1da177e4 | 1341 | } |
4cb912f1 | 1342 | context[len] = '\0'; |
1da177e4 LT |
1343 | rc = inode->i_op->getxattr(dentry, |
1344 | XATTR_NAME_SELINUX, | |
1345 | context, len); | |
1346 | } | |
1347 | dput(dentry); | |
1348 | if (rc < 0) { | |
1349 | if (rc != -ENODATA) { | |
744ba35e | 1350 | printk(KERN_WARNING "SELinux: %s: getxattr returned " |
dd6f953a | 1351 | "%d for dev=%s ino=%ld\n", __func__, |
1da177e4 LT |
1352 | -rc, inode->i_sb->s_id, inode->i_ino); |
1353 | kfree(context); | |
23970741 | 1354 | goto out_unlock; |
1da177e4 LT |
1355 | } |
1356 | /* Map ENODATA to the default file SID */ | |
1357 | sid = sbsec->def_sid; | |
1358 | rc = 0; | |
1359 | } else { | |
f5c1d5b2 | 1360 | rc = security_context_to_sid_default(context, rc, &sid, |
869ab514 SS |
1361 | sbsec->def_sid, |
1362 | GFP_NOFS); | |
1da177e4 | 1363 | if (rc) { |
4ba0a8ad EP |
1364 | char *dev = inode->i_sb->s_id; |
1365 | unsigned long ino = inode->i_ino; | |
1366 | ||
1367 | if (rc == -EINVAL) { | |
1368 | if (printk_ratelimit()) | |
1369 | printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " | |
1370 | "context=%s. This indicates you may need to relabel the inode or the " | |
1371 | "filesystem in question.\n", ino, dev, context); | |
1372 | } else { | |
1373 | printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " | |
1374 | "returned %d for dev=%s ino=%ld\n", | |
1375 | __func__, context, -rc, dev, ino); | |
1376 | } | |
1da177e4 LT |
1377 | kfree(context); |
1378 | /* Leave with the unlabeled SID */ | |
1379 | rc = 0; | |
1380 | break; | |
1381 | } | |
1382 | } | |
1383 | kfree(context); | |
1384 | isec->sid = sid; | |
1385 | break; | |
1386 | case SECURITY_FS_USE_TASK: | |
1387 | isec->sid = isec->task_sid; | |
1388 | break; | |
1389 | case SECURITY_FS_USE_TRANS: | |
1390 | /* Default to the fs SID. */ | |
1391 | isec->sid = sbsec->sid; | |
1392 | ||
1393 | /* Try to obtain a transition SID. */ | |
1394 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
652bb9b0 EP |
1395 | rc = security_transition_sid(isec->task_sid, sbsec->sid, |
1396 | isec->sclass, NULL, &sid); | |
1da177e4 | 1397 | if (rc) |
23970741 | 1398 | goto out_unlock; |
1da177e4 LT |
1399 | isec->sid = sid; |
1400 | break; | |
c312feb2 EP |
1401 | case SECURITY_FS_USE_MNTPOINT: |
1402 | isec->sid = sbsec->mntpoint_sid; | |
1403 | break; | |
1da177e4 | 1404 | default: |
c312feb2 | 1405 | /* Default to the fs superblock SID. */ |
1da177e4 LT |
1406 | isec->sid = sbsec->sid; |
1407 | ||
0d90a7ec | 1408 | if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { |
8e6c9693 | 1409 | if (opt_dentry) { |
1da177e4 | 1410 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
8e6c9693 | 1411 | rc = selinux_proc_get_sid(opt_dentry, |
1da177e4 LT |
1412 | isec->sclass, |
1413 | &sid); | |
1414 | if (rc) | |
23970741 | 1415 | goto out_unlock; |
1da177e4 LT |
1416 | isec->sid = sid; |
1417 | } | |
1418 | } | |
1419 | break; | |
1420 | } | |
1421 | ||
1422 | isec->initialized = 1; | |
1423 | ||
23970741 EP |
1424 | out_unlock: |
1425 | mutex_unlock(&isec->lock); | |
1da177e4 LT |
1426 | out: |
1427 | if (isec->sclass == SECCLASS_FILE) | |
1428 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1da177e4 LT |
1429 | return rc; |
1430 | } | |
1431 | ||
1432 | /* Convert a Linux signal to an access vector. */ | |
1433 | static inline u32 signal_to_av(int sig) | |
1434 | { | |
1435 | u32 perm = 0; | |
1436 | ||
1437 | switch (sig) { | |
1438 | case SIGCHLD: | |
1439 | /* Commonly granted from child to parent. */ | |
1440 | perm = PROCESS__SIGCHLD; | |
1441 | break; | |
1442 | case SIGKILL: | |
1443 | /* Cannot be caught or ignored */ | |
1444 | perm = PROCESS__SIGKILL; | |
1445 | break; | |
1446 | case SIGSTOP: | |
1447 | /* Cannot be caught or ignored */ | |
1448 | perm = PROCESS__SIGSTOP; | |
1449 | break; | |
1450 | default: | |
1451 | /* All other signals. */ | |
1452 | perm = PROCESS__SIGNAL; | |
1453 | break; | |
1454 | } | |
1455 | ||
1456 | return perm; | |
1457 | } | |
1458 | ||
d84f4f99 DH |
1459 | /* |
1460 | * Check permission between a pair of credentials | |
1461 | * fork check, ptrace check, etc. | |
1462 | */ | |
1463 | static int cred_has_perm(const struct cred *actor, | |
1464 | const struct cred *target, | |
1465 | u32 perms) | |
1466 | { | |
1467 | u32 asid = cred_sid(actor), tsid = cred_sid(target); | |
1468 | ||
1469 | return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); | |
1470 | } | |
1471 | ||
275bb41e | 1472 | /* |
88e67f3b | 1473 | * Check permission between a pair of tasks, e.g. signal checks, |
275bb41e DH |
1474 | * fork check, ptrace check, etc. |
1475 | * tsk1 is the actor and tsk2 is the target | |
3b11a1de | 1476 | * - this uses the default subjective creds of tsk1 |
275bb41e DH |
1477 | */ |
1478 | static int task_has_perm(const struct task_struct *tsk1, | |
1479 | const struct task_struct *tsk2, | |
1da177e4 LT |
1480 | u32 perms) |
1481 | { | |
275bb41e DH |
1482 | const struct task_security_struct *__tsec1, *__tsec2; |
1483 | u32 sid1, sid2; | |
1da177e4 | 1484 | |
275bb41e DH |
1485 | rcu_read_lock(); |
1486 | __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; | |
1487 | __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; | |
1488 | rcu_read_unlock(); | |
1489 | return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); | |
1da177e4 LT |
1490 | } |
1491 | ||
3b11a1de DH |
1492 | /* |
1493 | * Check permission between current and another task, e.g. signal checks, | |
1494 | * fork check, ptrace check, etc. | |
1495 | * current is the actor and tsk2 is the target | |
1496 | * - this uses current's subjective creds | |
1497 | */ | |
1498 | static int current_has_perm(const struct task_struct *tsk, | |
1499 | u32 perms) | |
1500 | { | |
1501 | u32 sid, tsid; | |
1502 | ||
1503 | sid = current_sid(); | |
1504 | tsid = task_sid(tsk); | |
1505 | return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); | |
1506 | } | |
1507 | ||
b68e418c SS |
1508 | #if CAP_LAST_CAP > 63 |
1509 | #error Fix SELinux to handle capabilities > 63. | |
1510 | #endif | |
1511 | ||
1da177e4 | 1512 | /* Check whether a task is allowed to use a capability. */ |
6a9de491 | 1513 | static int cred_has_capability(const struct cred *cred, |
06112163 | 1514 | int cap, int audit) |
1da177e4 | 1515 | { |
2bf49690 | 1516 | struct common_audit_data ad; |
06112163 | 1517 | struct av_decision avd; |
b68e418c | 1518 | u16 sclass; |
3699c53c | 1519 | u32 sid = cred_sid(cred); |
b68e418c | 1520 | u32 av = CAP_TO_MASK(cap); |
06112163 | 1521 | int rc; |
1da177e4 | 1522 | |
50c205f5 | 1523 | ad.type = LSM_AUDIT_DATA_CAP; |
1da177e4 LT |
1524 | ad.u.cap = cap; |
1525 | ||
b68e418c SS |
1526 | switch (CAP_TO_INDEX(cap)) { |
1527 | case 0: | |
1528 | sclass = SECCLASS_CAPABILITY; | |
1529 | break; | |
1530 | case 1: | |
1531 | sclass = SECCLASS_CAPABILITY2; | |
1532 | break; | |
1533 | default: | |
1534 | printk(KERN_ERR | |
1535 | "SELinux: out of range capability %d\n", cap); | |
1536 | BUG(); | |
a35c6c83 | 1537 | return -EINVAL; |
b68e418c | 1538 | } |
06112163 | 1539 | |
275bb41e | 1540 | rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); |
9ade0cf4 | 1541 | if (audit == SECURITY_CAP_AUDIT) { |
ab354062 | 1542 | int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); |
9ade0cf4 EP |
1543 | if (rc2) |
1544 | return rc2; | |
1545 | } | |
06112163 | 1546 | return rc; |
1da177e4 LT |
1547 | } |
1548 | ||
1549 | /* Check whether a task is allowed to use a system operation. */ | |
1550 | static int task_has_system(struct task_struct *tsk, | |
1551 | u32 perms) | |
1552 | { | |
275bb41e | 1553 | u32 sid = task_sid(tsk); |
1da177e4 | 1554 | |
275bb41e | 1555 | return avc_has_perm(sid, SECINITSID_KERNEL, |
1da177e4 LT |
1556 | SECCLASS_SYSTEM, perms, NULL); |
1557 | } | |
1558 | ||
1559 | /* Check whether a task has a particular permission to an inode. | |
1560 | The 'adp' parameter is optional and allows other audit | |
1561 | data to be passed (e.g. the dentry). */ | |
88e67f3b | 1562 | static int inode_has_perm(const struct cred *cred, |
1da177e4 LT |
1563 | struct inode *inode, |
1564 | u32 perms, | |
19e49834 | 1565 | struct common_audit_data *adp) |
1da177e4 | 1566 | { |
1da177e4 | 1567 | struct inode_security_struct *isec; |
275bb41e | 1568 | u32 sid; |
1da177e4 | 1569 | |
e0e81739 DH |
1570 | validate_creds(cred); |
1571 | ||
828dfe1d | 1572 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1573 | return 0; |
1574 | ||
88e67f3b | 1575 | sid = cred_sid(cred); |
1da177e4 LT |
1576 | isec = inode->i_security; |
1577 | ||
19e49834 | 1578 | return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); |
1da177e4 LT |
1579 | } |
1580 | ||
1581 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1582 | the dentry to help the auditing code to more easily generate the | |
1583 | pathname if needed. */ | |
88e67f3b | 1584 | static inline int dentry_has_perm(const struct cred *cred, |
1da177e4 LT |
1585 | struct dentry *dentry, |
1586 | u32 av) | |
1587 | { | |
1588 | struct inode *inode = dentry->d_inode; | |
2bf49690 | 1589 | struct common_audit_data ad; |
88e67f3b | 1590 | |
50c205f5 | 1591 | ad.type = LSM_AUDIT_DATA_DENTRY; |
2875fa00 | 1592 | ad.u.dentry = dentry; |
19e49834 | 1593 | return inode_has_perm(cred, inode, av, &ad); |
2875fa00 EP |
1594 | } |
1595 | ||
1596 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1597 | the path to help the auditing code to more easily generate the | |
1598 | pathname if needed. */ | |
1599 | static inline int path_has_perm(const struct cred *cred, | |
1600 | struct path *path, | |
1601 | u32 av) | |
1602 | { | |
1603 | struct inode *inode = path->dentry->d_inode; | |
1604 | struct common_audit_data ad; | |
1605 | ||
50c205f5 | 1606 | ad.type = LSM_AUDIT_DATA_PATH; |
2875fa00 | 1607 | ad.u.path = *path; |
19e49834 | 1608 | return inode_has_perm(cred, inode, av, &ad); |
1da177e4 LT |
1609 | } |
1610 | ||
13f8e981 DH |
1611 | /* Same as path_has_perm, but uses the inode from the file struct. */ |
1612 | static inline int file_path_has_perm(const struct cred *cred, | |
1613 | struct file *file, | |
1614 | u32 av) | |
1615 | { | |
1616 | struct common_audit_data ad; | |
1617 | ||
1618 | ad.type = LSM_AUDIT_DATA_PATH; | |
1619 | ad.u.path = file->f_path; | |
19e49834 | 1620 | return inode_has_perm(cred, file_inode(file), av, &ad); |
13f8e981 DH |
1621 | } |
1622 | ||
1da177e4 LT |
1623 | /* Check whether a task can use an open file descriptor to |
1624 | access an inode in a given way. Check access to the | |
1625 | descriptor itself, and then use dentry_has_perm to | |
1626 | check a particular permission to the file. | |
1627 | Access to the descriptor is implicitly granted if it | |
1628 | has the same SID as the process. If av is zero, then | |
1629 | access to the file is not checked, e.g. for cases | |
1630 | where only the descriptor is affected like seek. */ | |
88e67f3b DH |
1631 | static int file_has_perm(const struct cred *cred, |
1632 | struct file *file, | |
1633 | u32 av) | |
1da177e4 | 1634 | { |
1da177e4 | 1635 | struct file_security_struct *fsec = file->f_security; |
496ad9aa | 1636 | struct inode *inode = file_inode(file); |
2bf49690 | 1637 | struct common_audit_data ad; |
88e67f3b | 1638 | u32 sid = cred_sid(cred); |
1da177e4 LT |
1639 | int rc; |
1640 | ||
50c205f5 | 1641 | ad.type = LSM_AUDIT_DATA_PATH; |
f48b7399 | 1642 | ad.u.path = file->f_path; |
1da177e4 | 1643 | |
275bb41e DH |
1644 | if (sid != fsec->sid) { |
1645 | rc = avc_has_perm(sid, fsec->sid, | |
1da177e4 LT |
1646 | SECCLASS_FD, |
1647 | FD__USE, | |
1648 | &ad); | |
1649 | if (rc) | |
88e67f3b | 1650 | goto out; |
1da177e4 LT |
1651 | } |
1652 | ||
1653 | /* av is zero if only checking access to the descriptor. */ | |
88e67f3b | 1654 | rc = 0; |
1da177e4 | 1655 | if (av) |
19e49834 | 1656 | rc = inode_has_perm(cred, inode, av, &ad); |
1da177e4 | 1657 | |
88e67f3b DH |
1658 | out: |
1659 | return rc; | |
1da177e4 LT |
1660 | } |
1661 | ||
1662 | /* Check whether a task can create a file. */ | |
1663 | static int may_create(struct inode *dir, | |
1664 | struct dentry *dentry, | |
1665 | u16 tclass) | |
1666 | { | |
5fb49870 | 1667 | const struct task_security_struct *tsec = current_security(); |
1da177e4 LT |
1668 | struct inode_security_struct *dsec; |
1669 | struct superblock_security_struct *sbsec; | |
275bb41e | 1670 | u32 sid, newsid; |
2bf49690 | 1671 | struct common_audit_data ad; |
1da177e4 LT |
1672 | int rc; |
1673 | ||
1da177e4 LT |
1674 | dsec = dir->i_security; |
1675 | sbsec = dir->i_sb->s_security; | |
1676 | ||
275bb41e DH |
1677 | sid = tsec->sid; |
1678 | newsid = tsec->create_sid; | |
1679 | ||
50c205f5 | 1680 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1681 | ad.u.dentry = dentry; |
1da177e4 | 1682 | |
275bb41e | 1683 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
1684 | DIR__ADD_NAME | DIR__SEARCH, |
1685 | &ad); | |
1686 | if (rc) | |
1687 | return rc; | |
1688 | ||
12f348b9 | 1689 | if (!newsid || !(sbsec->flags & SBLABEL_MNT)) { |
cb1e922f EP |
1690 | rc = security_transition_sid(sid, dsec->sid, tclass, |
1691 | &dentry->d_name, &newsid); | |
1da177e4 LT |
1692 | if (rc) |
1693 | return rc; | |
1694 | } | |
1695 | ||
275bb41e | 1696 | rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); |
1da177e4 LT |
1697 | if (rc) |
1698 | return rc; | |
1699 | ||
1700 | return avc_has_perm(newsid, sbsec->sid, | |
1701 | SECCLASS_FILESYSTEM, | |
1702 | FILESYSTEM__ASSOCIATE, &ad); | |
1703 | } | |
1704 | ||
4eb582cf ML |
1705 | /* Check whether a task can create a key. */ |
1706 | static int may_create_key(u32 ksid, | |
1707 | struct task_struct *ctx) | |
1708 | { | |
275bb41e | 1709 | u32 sid = task_sid(ctx); |
4eb582cf | 1710 | |
275bb41e | 1711 | return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); |
4eb582cf ML |
1712 | } |
1713 | ||
828dfe1d EP |
1714 | #define MAY_LINK 0 |
1715 | #define MAY_UNLINK 1 | |
1716 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1717 | |
1718 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1719 | static int may_link(struct inode *dir, | |
1720 | struct dentry *dentry, | |
1721 | int kind) | |
1722 | ||
1723 | { | |
1da177e4 | 1724 | struct inode_security_struct *dsec, *isec; |
2bf49690 | 1725 | struct common_audit_data ad; |
275bb41e | 1726 | u32 sid = current_sid(); |
1da177e4 LT |
1727 | u32 av; |
1728 | int rc; | |
1729 | ||
1da177e4 LT |
1730 | dsec = dir->i_security; |
1731 | isec = dentry->d_inode->i_security; | |
1732 | ||
50c205f5 | 1733 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 1734 | ad.u.dentry = dentry; |
1da177e4 LT |
1735 | |
1736 | av = DIR__SEARCH; | |
1737 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
275bb41e | 1738 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
1739 | if (rc) |
1740 | return rc; | |
1741 | ||
1742 | switch (kind) { | |
1743 | case MAY_LINK: | |
1744 | av = FILE__LINK; | |
1745 | break; | |
1746 | case MAY_UNLINK: | |
1747 | av = FILE__UNLINK; | |
1748 | break; | |
1749 | case MAY_RMDIR: | |
1750 | av = DIR__RMDIR; | |
1751 | break; | |
1752 | default: | |
744ba35e EP |
1753 | printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", |
1754 | __func__, kind); | |
1da177e4 LT |
1755 | return 0; |
1756 | } | |
1757 | ||
275bb41e | 1758 | rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); |
1da177e4 LT |
1759 | return rc; |
1760 | } | |
1761 | ||
1762 | static inline int may_rename(struct inode *old_dir, | |
1763 | struct dentry *old_dentry, | |
1764 | struct inode *new_dir, | |
1765 | struct dentry *new_dentry) | |
1766 | { | |
1da177e4 | 1767 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; |
2bf49690 | 1768 | struct common_audit_data ad; |
275bb41e | 1769 | u32 sid = current_sid(); |
1da177e4 LT |
1770 | u32 av; |
1771 | int old_is_dir, new_is_dir; | |
1772 | int rc; | |
1773 | ||
1da177e4 LT |
1774 | old_dsec = old_dir->i_security; |
1775 | old_isec = old_dentry->d_inode->i_security; | |
1776 | old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); | |
1777 | new_dsec = new_dir->i_security; | |
1778 | ||
50c205f5 | 1779 | ad.type = LSM_AUDIT_DATA_DENTRY; |
1da177e4 | 1780 | |
a269434d | 1781 | ad.u.dentry = old_dentry; |
275bb41e | 1782 | rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, |
1da177e4 LT |
1783 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); |
1784 | if (rc) | |
1785 | return rc; | |
275bb41e | 1786 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
1787 | old_isec->sclass, FILE__RENAME, &ad); |
1788 | if (rc) | |
1789 | return rc; | |
1790 | if (old_is_dir && new_dir != old_dir) { | |
275bb41e | 1791 | rc = avc_has_perm(sid, old_isec->sid, |
1da177e4 LT |
1792 | old_isec->sclass, DIR__REPARENT, &ad); |
1793 | if (rc) | |
1794 | return rc; | |
1795 | } | |
1796 | ||
a269434d | 1797 | ad.u.dentry = new_dentry; |
1da177e4 LT |
1798 | av = DIR__ADD_NAME | DIR__SEARCH; |
1799 | if (new_dentry->d_inode) | |
1800 | av |= DIR__REMOVE_NAME; | |
275bb41e | 1801 | rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); |
1da177e4 LT |
1802 | if (rc) |
1803 | return rc; | |
1804 | if (new_dentry->d_inode) { | |
1805 | new_isec = new_dentry->d_inode->i_security; | |
1806 | new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); | |
275bb41e | 1807 | rc = avc_has_perm(sid, new_isec->sid, |
1da177e4 LT |
1808 | new_isec->sclass, |
1809 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1810 | if (rc) | |
1811 | return rc; | |
1812 | } | |
1813 | ||
1814 | return 0; | |
1815 | } | |
1816 | ||
1817 | /* Check whether a task can perform a filesystem operation. */ | |
88e67f3b | 1818 | static int superblock_has_perm(const struct cred *cred, |
1da177e4 LT |
1819 | struct super_block *sb, |
1820 | u32 perms, | |
2bf49690 | 1821 | struct common_audit_data *ad) |
1da177e4 | 1822 | { |
1da177e4 | 1823 | struct superblock_security_struct *sbsec; |
88e67f3b | 1824 | u32 sid = cred_sid(cred); |
1da177e4 | 1825 | |
1da177e4 | 1826 | sbsec = sb->s_security; |
275bb41e | 1827 | return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); |
1da177e4 LT |
1828 | } |
1829 | ||
1830 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1831 | static inline u32 file_mask_to_av(int mode, int mask) | |
1832 | { | |
1833 | u32 av = 0; | |
1834 | ||
dba19c60 | 1835 | if (!S_ISDIR(mode)) { |
1da177e4 LT |
1836 | if (mask & MAY_EXEC) |
1837 | av |= FILE__EXECUTE; | |
1838 | if (mask & MAY_READ) | |
1839 | av |= FILE__READ; | |
1840 | ||
1841 | if (mask & MAY_APPEND) | |
1842 | av |= FILE__APPEND; | |
1843 | else if (mask & MAY_WRITE) | |
1844 | av |= FILE__WRITE; | |
1845 | ||
1846 | } else { | |
1847 | if (mask & MAY_EXEC) | |
1848 | av |= DIR__SEARCH; | |
1849 | if (mask & MAY_WRITE) | |
1850 | av |= DIR__WRITE; | |
1851 | if (mask & MAY_READ) | |
1852 | av |= DIR__READ; | |
1853 | } | |
1854 | ||
1855 | return av; | |
1856 | } | |
1857 | ||
8b6a5a37 EP |
1858 | /* Convert a Linux file to an access vector. */ |
1859 | static inline u32 file_to_av(struct file *file) | |
1860 | { | |
1861 | u32 av = 0; | |
1862 | ||
1863 | if (file->f_mode & FMODE_READ) | |
1864 | av |= FILE__READ; | |
1865 | if (file->f_mode & FMODE_WRITE) { | |
1866 | if (file->f_flags & O_APPEND) | |
1867 | av |= FILE__APPEND; | |
1868 | else | |
1869 | av |= FILE__WRITE; | |
1870 | } | |
1871 | if (!av) { | |
1872 | /* | |
1873 | * Special file opened with flags 3 for ioctl-only use. | |
1874 | */ | |
1875 | av = FILE__IOCTL; | |
1876 | } | |
1877 | ||
1878 | return av; | |
1879 | } | |
1880 | ||
b0c636b9 | 1881 | /* |
8b6a5a37 | 1882 | * Convert a file to an access vector and include the correct open |
b0c636b9 EP |
1883 | * open permission. |
1884 | */ | |
8b6a5a37 | 1885 | static inline u32 open_file_to_av(struct file *file) |
b0c636b9 | 1886 | { |
8b6a5a37 | 1887 | u32 av = file_to_av(file); |
b0c636b9 | 1888 | |
49b7b8de EP |
1889 | if (selinux_policycap_openperm) |
1890 | av |= FILE__OPEN; | |
1891 | ||
b0c636b9 EP |
1892 | return av; |
1893 | } | |
1894 | ||
1da177e4 LT |
1895 | /* Hook functions begin here. */ |
1896 | ||
9e48858f | 1897 | static int selinux_ptrace_access_check(struct task_struct *child, |
5cd9c58f | 1898 | unsigned int mode) |
1da177e4 | 1899 | { |
1da177e4 LT |
1900 | int rc; |
1901 | ||
9e48858f | 1902 | rc = cap_ptrace_access_check(child, mode); |
1da177e4 LT |
1903 | if (rc) |
1904 | return rc; | |
1905 | ||
69f594a3 | 1906 | if (mode & PTRACE_MODE_READ) { |
275bb41e DH |
1907 | u32 sid = current_sid(); |
1908 | u32 csid = task_sid(child); | |
1909 | return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
006ebb40 SS |
1910 | } |
1911 | ||
3b11a1de | 1912 | return current_has_perm(child, PROCESS__PTRACE); |
5cd9c58f DH |
1913 | } |
1914 | ||
1915 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
1916 | { | |
1917 | int rc; | |
1918 | ||
200ac532 | 1919 | rc = cap_ptrace_traceme(parent); |
5cd9c58f DH |
1920 | if (rc) |
1921 | return rc; | |
1922 | ||
1923 | return task_has_perm(parent, current, PROCESS__PTRACE); | |
1da177e4 LT |
1924 | } |
1925 | ||
1926 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 1927 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 LT |
1928 | { |
1929 | int error; | |
1930 | ||
3b11a1de | 1931 | error = current_has_perm(target, PROCESS__GETCAP); |
1da177e4 LT |
1932 | if (error) |
1933 | return error; | |
1934 | ||
200ac532 | 1935 | return cap_capget(target, effective, inheritable, permitted); |
1da177e4 LT |
1936 | } |
1937 | ||
d84f4f99 DH |
1938 | static int selinux_capset(struct cred *new, const struct cred *old, |
1939 | const kernel_cap_t *effective, | |
1940 | const kernel_cap_t *inheritable, | |
1941 | const kernel_cap_t *permitted) | |
1da177e4 LT |
1942 | { |
1943 | int error; | |
1944 | ||
200ac532 | 1945 | error = cap_capset(new, old, |
d84f4f99 | 1946 | effective, inheritable, permitted); |
1da177e4 LT |
1947 | if (error) |
1948 | return error; | |
1949 | ||
d84f4f99 | 1950 | return cred_has_perm(old, new, PROCESS__SETCAP); |
1da177e4 LT |
1951 | } |
1952 | ||
5626d3e8 JM |
1953 | /* |
1954 | * (This comment used to live with the selinux_task_setuid hook, | |
1955 | * which was removed). | |
1956 | * | |
1957 | * Since setuid only affects the current process, and since the SELinux | |
1958 | * controls are not based on the Linux identity attributes, SELinux does not | |
1959 | * need to control this operation. However, SELinux does control the use of | |
1960 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
1961 | */ | |
1962 | ||
6a9de491 EP |
1963 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, |
1964 | int cap, int audit) | |
1da177e4 LT |
1965 | { |
1966 | int rc; | |
1967 | ||
6a9de491 | 1968 | rc = cap_capable(cred, ns, cap, audit); |
1da177e4 LT |
1969 | if (rc) |
1970 | return rc; | |
1971 | ||
6a9de491 | 1972 | return cred_has_capability(cred, cap, audit); |
1da177e4 LT |
1973 | } |
1974 | ||
1da177e4 LT |
1975 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) |
1976 | { | |
88e67f3b | 1977 | const struct cred *cred = current_cred(); |
1da177e4 LT |
1978 | int rc = 0; |
1979 | ||
1980 | if (!sb) | |
1981 | return 0; | |
1982 | ||
1983 | switch (cmds) { | |
828dfe1d EP |
1984 | case Q_SYNC: |
1985 | case Q_QUOTAON: | |
1986 | case Q_QUOTAOFF: | |
1987 | case Q_SETINFO: | |
1988 | case Q_SETQUOTA: | |
88e67f3b | 1989 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); |
828dfe1d EP |
1990 | break; |
1991 | case Q_GETFMT: | |
1992 | case Q_GETINFO: | |
1993 | case Q_GETQUOTA: | |
88e67f3b | 1994 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); |
828dfe1d EP |
1995 | break; |
1996 | default: | |
1997 | rc = 0; /* let the kernel handle invalid cmds */ | |
1998 | break; | |
1da177e4 LT |
1999 | } |
2000 | return rc; | |
2001 | } | |
2002 | ||
2003 | static int selinux_quota_on(struct dentry *dentry) | |
2004 | { | |
88e67f3b DH |
2005 | const struct cred *cred = current_cred(); |
2006 | ||
2875fa00 | 2007 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); |
1da177e4 LT |
2008 | } |
2009 | ||
12b3052c | 2010 | static int selinux_syslog(int type) |
1da177e4 LT |
2011 | { |
2012 | int rc; | |
2013 | ||
1da177e4 | 2014 | switch (type) { |
d78ca3cd KC |
2015 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ |
2016 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
828dfe1d EP |
2017 | rc = task_has_system(current, SYSTEM__SYSLOG_READ); |
2018 | break; | |
d78ca3cd KC |
2019 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ |
2020 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2021 | /* Set level of messages printed to console */ | |
2022 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
828dfe1d EP |
2023 | rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); |
2024 | break; | |
d78ca3cd KC |
2025 | case SYSLOG_ACTION_CLOSE: /* Close log */ |
2026 | case SYSLOG_ACTION_OPEN: /* Open log */ | |
2027 | case SYSLOG_ACTION_READ: /* Read from log */ | |
2028 | case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ | |
2029 | case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ | |
828dfe1d EP |
2030 | default: |
2031 | rc = task_has_system(current, SYSTEM__SYSLOG_MOD); | |
2032 | break; | |
1da177e4 LT |
2033 | } |
2034 | return rc; | |
2035 | } | |
2036 | ||
2037 | /* | |
2038 | * Check that a process has enough memory to allocate a new virtual | |
2039 | * mapping. 0 means there is enough memory for the allocation to | |
2040 | * succeed and -ENOMEM implies there is not. | |
2041 | * | |
1da177e4 LT |
2042 | * Do not audit the selinux permission check, as this is applied to all |
2043 | * processes that allocate mappings. | |
2044 | */ | |
34b4e4aa | 2045 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
2046 | { |
2047 | int rc, cap_sys_admin = 0; | |
1da177e4 | 2048 | |
6a9de491 | 2049 | rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN, |
3699c53c | 2050 | SECURITY_CAP_NOAUDIT); |
1da177e4 LT |
2051 | if (rc == 0) |
2052 | cap_sys_admin = 1; | |
2053 | ||
34b4e4aa | 2054 | return __vm_enough_memory(mm, pages, cap_sys_admin); |
1da177e4 LT |
2055 | } |
2056 | ||
2057 | /* binprm security operations */ | |
2058 | ||
a6f76f23 | 2059 | static int selinux_bprm_set_creds(struct linux_binprm *bprm) |
1da177e4 | 2060 | { |
a6f76f23 DH |
2061 | const struct task_security_struct *old_tsec; |
2062 | struct task_security_struct *new_tsec; | |
1da177e4 | 2063 | struct inode_security_struct *isec; |
2bf49690 | 2064 | struct common_audit_data ad; |
496ad9aa | 2065 | struct inode *inode = file_inode(bprm->file); |
1da177e4 LT |
2066 | int rc; |
2067 | ||
200ac532 | 2068 | rc = cap_bprm_set_creds(bprm); |
1da177e4 LT |
2069 | if (rc) |
2070 | return rc; | |
2071 | ||
a6f76f23 DH |
2072 | /* SELinux context only depends on initial program or script and not |
2073 | * the script interpreter */ | |
2074 | if (bprm->cred_prepared) | |
1da177e4 LT |
2075 | return 0; |
2076 | ||
a6f76f23 DH |
2077 | old_tsec = current_security(); |
2078 | new_tsec = bprm->cred->security; | |
1da177e4 LT |
2079 | isec = inode->i_security; |
2080 | ||
2081 | /* Default to the current task SID. */ | |
a6f76f23 DH |
2082 | new_tsec->sid = old_tsec->sid; |
2083 | new_tsec->osid = old_tsec->sid; | |
1da177e4 | 2084 | |
28eba5bf | 2085 | /* Reset fs, key, and sock SIDs on execve. */ |
a6f76f23 DH |
2086 | new_tsec->create_sid = 0; |
2087 | new_tsec->keycreate_sid = 0; | |
2088 | new_tsec->sockcreate_sid = 0; | |
1da177e4 | 2089 | |
a6f76f23 DH |
2090 | if (old_tsec->exec_sid) { |
2091 | new_tsec->sid = old_tsec->exec_sid; | |
1da177e4 | 2092 | /* Reset exec SID on execve. */ |
a6f76f23 | 2093 | new_tsec->exec_sid = 0; |
259e5e6c AL |
2094 | |
2095 | /* | |
2096 | * Minimize confusion: if no_new_privs and a transition is | |
2097 | * explicitly requested, then fail the exec. | |
2098 | */ | |
2099 | if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) | |
2100 | return -EPERM; | |
1da177e4 LT |
2101 | } else { |
2102 | /* Check for a default transition on this program. */ | |
a6f76f23 | 2103 | rc = security_transition_sid(old_tsec->sid, isec->sid, |
652bb9b0 EP |
2104 | SECCLASS_PROCESS, NULL, |
2105 | &new_tsec->sid); | |
1da177e4 LT |
2106 | if (rc) |
2107 | return rc; | |
2108 | } | |
2109 | ||
50c205f5 | 2110 | ad.type = LSM_AUDIT_DATA_PATH; |
f48b7399 | 2111 | ad.u.path = bprm->file->f_path; |
1da177e4 | 2112 | |
259e5e6c AL |
2113 | if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) || |
2114 | (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)) | |
a6f76f23 | 2115 | new_tsec->sid = old_tsec->sid; |
1da177e4 | 2116 | |
a6f76f23 DH |
2117 | if (new_tsec->sid == old_tsec->sid) { |
2118 | rc = avc_has_perm(old_tsec->sid, isec->sid, | |
1da177e4 LT |
2119 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); |
2120 | if (rc) | |
2121 | return rc; | |
2122 | } else { | |
2123 | /* Check permissions for the transition. */ | |
a6f76f23 | 2124 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, |
1da177e4 LT |
2125 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); |
2126 | if (rc) | |
2127 | return rc; | |
2128 | ||
a6f76f23 | 2129 | rc = avc_has_perm(new_tsec->sid, isec->sid, |
1da177e4 LT |
2130 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); |
2131 | if (rc) | |
2132 | return rc; | |
2133 | ||
a6f76f23 DH |
2134 | /* Check for shared state */ |
2135 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
2136 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, | |
2137 | SECCLASS_PROCESS, PROCESS__SHARE, | |
2138 | NULL); | |
2139 | if (rc) | |
2140 | return -EPERM; | |
2141 | } | |
2142 | ||
2143 | /* Make sure that anyone attempting to ptrace over a task that | |
2144 | * changes its SID has the appropriate permit */ | |
2145 | if (bprm->unsafe & | |
2146 | (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { | |
2147 | struct task_struct *tracer; | |
2148 | struct task_security_struct *sec; | |
2149 | u32 ptsid = 0; | |
2150 | ||
2151 | rcu_read_lock(); | |
06d98473 | 2152 | tracer = ptrace_parent(current); |
a6f76f23 DH |
2153 | if (likely(tracer != NULL)) { |
2154 | sec = __task_cred(tracer)->security; | |
2155 | ptsid = sec->sid; | |
2156 | } | |
2157 | rcu_read_unlock(); | |
2158 | ||
2159 | if (ptsid != 0) { | |
2160 | rc = avc_has_perm(ptsid, new_tsec->sid, | |
2161 | SECCLASS_PROCESS, | |
2162 | PROCESS__PTRACE, NULL); | |
2163 | if (rc) | |
2164 | return -EPERM; | |
2165 | } | |
2166 | } | |
1da177e4 | 2167 | |
a6f76f23 DH |
2168 | /* Clear any possibly unsafe personality bits on exec: */ |
2169 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
1da177e4 LT |
2170 | } |
2171 | ||
1da177e4 LT |
2172 | return 0; |
2173 | } | |
2174 | ||
828dfe1d | 2175 | static int selinux_bprm_secureexec(struct linux_binprm *bprm) |
1da177e4 | 2176 | { |
5fb49870 | 2177 | const struct task_security_struct *tsec = current_security(); |
275bb41e | 2178 | u32 sid, osid; |
1da177e4 LT |
2179 | int atsecure = 0; |
2180 | ||
275bb41e DH |
2181 | sid = tsec->sid; |
2182 | osid = tsec->osid; | |
2183 | ||
2184 | if (osid != sid) { | |
1da177e4 LT |
2185 | /* Enable secure mode for SIDs transitions unless |
2186 | the noatsecure permission is granted between | |
2187 | the two SIDs, i.e. ahp returns 0. */ | |
275bb41e | 2188 | atsecure = avc_has_perm(osid, sid, |
a6f76f23 DH |
2189 | SECCLASS_PROCESS, |
2190 | PROCESS__NOATSECURE, NULL); | |
1da177e4 LT |
2191 | } |
2192 | ||
200ac532 | 2193 | return (atsecure || cap_bprm_secureexec(bprm)); |
1da177e4 LT |
2194 | } |
2195 | ||
c3c073f8 AV |
2196 | static int match_file(const void *p, struct file *file, unsigned fd) |
2197 | { | |
2198 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2199 | } | |
2200 | ||
1da177e4 | 2201 | /* Derived from fs/exec.c:flush_old_files. */ |
745ca247 DH |
2202 | static inline void flush_unauthorized_files(const struct cred *cred, |
2203 | struct files_struct *files) | |
1da177e4 | 2204 | { |
1da177e4 | 2205 | struct file *file, *devnull = NULL; |
b20c8122 | 2206 | struct tty_struct *tty; |
24ec839c | 2207 | int drop_tty = 0; |
c3c073f8 | 2208 | unsigned n; |
1da177e4 | 2209 | |
24ec839c | 2210 | tty = get_current_tty(); |
1da177e4 | 2211 | if (tty) { |
ee2ffa0d | 2212 | spin_lock(&tty_files_lock); |
37dd0bd0 | 2213 | if (!list_empty(&tty->tty_files)) { |
d996b62a | 2214 | struct tty_file_private *file_priv; |
37dd0bd0 | 2215 | |
1da177e4 | 2216 | /* Revalidate access to controlling tty. |
13f8e981 DH |
2217 | Use file_path_has_perm on the tty path directly |
2218 | rather than using file_has_perm, as this particular | |
2219 | open file may belong to another process and we are | |
2220 | only interested in the inode-based check here. */ | |
d996b62a NP |
2221 | file_priv = list_first_entry(&tty->tty_files, |
2222 | struct tty_file_private, list); | |
2223 | file = file_priv->file; | |
13f8e981 | 2224 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) |
24ec839c | 2225 | drop_tty = 1; |
1da177e4 | 2226 | } |
ee2ffa0d | 2227 | spin_unlock(&tty_files_lock); |
452a00d2 | 2228 | tty_kref_put(tty); |
1da177e4 | 2229 | } |
98a27ba4 EB |
2230 | /* Reset controlling tty. */ |
2231 | if (drop_tty) | |
2232 | no_tty(); | |
1da177e4 LT |
2233 | |
2234 | /* Revalidate access to inherited open files. */ | |
c3c073f8 AV |
2235 | n = iterate_fd(files, 0, match_file, cred); |
2236 | if (!n) /* none found? */ | |
2237 | return; | |
1da177e4 | 2238 | |
c3c073f8 | 2239 | devnull = dentry_open(&selinux_null, O_RDWR, cred); |
45525b26 AV |
2240 | if (IS_ERR(devnull)) |
2241 | devnull = NULL; | |
2242 | /* replace all the matching ones with this */ | |
2243 | do { | |
2244 | replace_fd(n - 1, devnull, 0); | |
2245 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2246 | if (devnull) | |
c3c073f8 | 2247 | fput(devnull); |
1da177e4 LT |
2248 | } |
2249 | ||
a6f76f23 DH |
2250 | /* |
2251 | * Prepare a process for imminent new credential changes due to exec | |
2252 | */ | |
2253 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
1da177e4 | 2254 | { |
a6f76f23 DH |
2255 | struct task_security_struct *new_tsec; |
2256 | struct rlimit *rlim, *initrlim; | |
2257 | int rc, i; | |
d84f4f99 | 2258 | |
a6f76f23 DH |
2259 | new_tsec = bprm->cred->security; |
2260 | if (new_tsec->sid == new_tsec->osid) | |
2261 | return; | |
1da177e4 | 2262 | |
a6f76f23 DH |
2263 | /* Close files for which the new task SID is not authorized. */ |
2264 | flush_unauthorized_files(bprm->cred, current->files); | |
0356357c | 2265 | |
a6f76f23 DH |
2266 | /* Always clear parent death signal on SID transitions. */ |
2267 | current->pdeath_signal = 0; | |
0356357c | 2268 | |
a6f76f23 DH |
2269 | /* Check whether the new SID can inherit resource limits from the old |
2270 | * SID. If not, reset all soft limits to the lower of the current | |
2271 | * task's hard limit and the init task's soft limit. | |
2272 | * | |
2273 | * Note that the setting of hard limits (even to lower them) can be | |
2274 | * controlled by the setrlimit check. The inclusion of the init task's | |
2275 | * soft limit into the computation is to avoid resetting soft limits | |
2276 | * higher than the default soft limit for cases where the default is | |
2277 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2278 | */ | |
2279 | rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
2280 | PROCESS__RLIMITINH, NULL); | |
2281 | if (rc) { | |
eb2d55a3 ON |
2282 | /* protect against do_prlimit() */ |
2283 | task_lock(current); | |
a6f76f23 DH |
2284 | for (i = 0; i < RLIM_NLIMITS; i++) { |
2285 | rlim = current->signal->rlim + i; | |
2286 | initrlim = init_task.signal->rlim + i; | |
2287 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
1da177e4 | 2288 | } |
eb2d55a3 ON |
2289 | task_unlock(current); |
2290 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
1da177e4 LT |
2291 | } |
2292 | } | |
2293 | ||
2294 | /* | |
a6f76f23 DH |
2295 | * Clean up the process immediately after the installation of new credentials |
2296 | * due to exec | |
1da177e4 | 2297 | */ |
a6f76f23 | 2298 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) |
1da177e4 | 2299 | { |
a6f76f23 | 2300 | const struct task_security_struct *tsec = current_security(); |
1da177e4 | 2301 | struct itimerval itimer; |
a6f76f23 | 2302 | u32 osid, sid; |
1da177e4 LT |
2303 | int rc, i; |
2304 | ||
a6f76f23 DH |
2305 | osid = tsec->osid; |
2306 | sid = tsec->sid; | |
2307 | ||
2308 | if (sid == osid) | |
1da177e4 LT |
2309 | return; |
2310 | ||
a6f76f23 DH |
2311 | /* Check whether the new SID can inherit signal state from the old SID. |
2312 | * If not, clear itimers to avoid subsequent signal generation and | |
2313 | * flush and unblock signals. | |
2314 | * | |
2315 | * This must occur _after_ the task SID has been updated so that any | |
2316 | * kill done after the flush will be checked against the new SID. | |
2317 | */ | |
2318 | rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
1da177e4 LT |
2319 | if (rc) { |
2320 | memset(&itimer, 0, sizeof itimer); | |
2321 | for (i = 0; i < 3; i++) | |
2322 | do_setitimer(i, &itimer, NULL); | |
1da177e4 | 2323 | spin_lock_irq(¤t->sighand->siglock); |
3bcac026 DH |
2324 | if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) { |
2325 | __flush_signals(current); | |
2326 | flush_signal_handlers(current, 1); | |
2327 | sigemptyset(¤t->blocked); | |
2328 | } | |
1da177e4 LT |
2329 | spin_unlock_irq(¤t->sighand->siglock); |
2330 | } | |
2331 | ||
a6f76f23 DH |
2332 | /* Wake up the parent if it is waiting so that it can recheck |
2333 | * wait permission to the new task SID. */ | |
ecd6de3c | 2334 | read_lock(&tasklist_lock); |
0b7570e7 | 2335 | __wake_up_parent(current, current->real_parent); |
ecd6de3c | 2336 | read_unlock(&tasklist_lock); |
1da177e4 LT |
2337 | } |
2338 | ||
2339 | /* superblock security operations */ | |
2340 | ||
2341 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2342 | { | |
2343 | return superblock_alloc_security(sb); | |
2344 | } | |
2345 | ||
2346 | static void selinux_sb_free_security(struct super_block *sb) | |
2347 | { | |
2348 | superblock_free_security(sb); | |
2349 | } | |
2350 | ||
2351 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2352 | { | |
2353 | if (plen > olen) | |
2354 | return 0; | |
2355 | ||
2356 | return !memcmp(prefix, option, plen); | |
2357 | } | |
2358 | ||
2359 | static inline int selinux_option(char *option, int len) | |
2360 | { | |
832cbd9a EP |
2361 | return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || |
2362 | match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || | |
2363 | match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || | |
11689d47 DQ |
2364 | match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || |
2365 | match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); | |
1da177e4 LT |
2366 | } |
2367 | ||
2368 | static inline void take_option(char **to, char *from, int *first, int len) | |
2369 | { | |
2370 | if (!*first) { | |
2371 | **to = ','; | |
2372 | *to += 1; | |
3528a953 | 2373 | } else |
1da177e4 LT |
2374 | *first = 0; |
2375 | memcpy(*to, from, len); | |
2376 | *to += len; | |
2377 | } | |
2378 | ||
828dfe1d EP |
2379 | static inline void take_selinux_option(char **to, char *from, int *first, |
2380 | int len) | |
3528a953 CO |
2381 | { |
2382 | int current_size = 0; | |
2383 | ||
2384 | if (!*first) { | |
2385 | **to = '|'; | |
2386 | *to += 1; | |
828dfe1d | 2387 | } else |
3528a953 CO |
2388 | *first = 0; |
2389 | ||
2390 | while (current_size < len) { | |
2391 | if (*from != '"') { | |
2392 | **to = *from; | |
2393 | *to += 1; | |
2394 | } | |
2395 | from += 1; | |
2396 | current_size += 1; | |
2397 | } | |
2398 | } | |
2399 | ||
e0007529 | 2400 | static int selinux_sb_copy_data(char *orig, char *copy) |
1da177e4 LT |
2401 | { |
2402 | int fnosec, fsec, rc = 0; | |
2403 | char *in_save, *in_curr, *in_end; | |
2404 | char *sec_curr, *nosec_save, *nosec; | |
3528a953 | 2405 | int open_quote = 0; |
1da177e4 LT |
2406 | |
2407 | in_curr = orig; | |
2408 | sec_curr = copy; | |
2409 | ||
1da177e4 LT |
2410 | nosec = (char *)get_zeroed_page(GFP_KERNEL); |
2411 | if (!nosec) { | |
2412 | rc = -ENOMEM; | |
2413 | goto out; | |
2414 | } | |
2415 | ||
2416 | nosec_save = nosec; | |
2417 | fnosec = fsec = 1; | |
2418 | in_save = in_end = orig; | |
2419 | ||
2420 | do { | |
3528a953 CO |
2421 | if (*in_end == '"') |
2422 | open_quote = !open_quote; | |
2423 | if ((*in_end == ',' && open_quote == 0) || | |
2424 | *in_end == '\0') { | |
1da177e4 LT |
2425 | int len = in_end - in_curr; |
2426 | ||
2427 | if (selinux_option(in_curr, len)) | |
3528a953 | 2428 | take_selinux_option(&sec_curr, in_curr, &fsec, len); |
1da177e4 LT |
2429 | else |
2430 | take_option(&nosec, in_curr, &fnosec, len); | |
2431 | ||
2432 | in_curr = in_end + 1; | |
2433 | } | |
2434 | } while (*in_end++); | |
2435 | ||
6931dfc9 | 2436 | strcpy(in_save, nosec_save); |
da3caa20 | 2437 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
2438 | out: |
2439 | return rc; | |
2440 | } | |
2441 | ||
026eb167 EP |
2442 | static int selinux_sb_remount(struct super_block *sb, void *data) |
2443 | { | |
2444 | int rc, i, *flags; | |
2445 | struct security_mnt_opts opts; | |
2446 | char *secdata, **mount_options; | |
2447 | struct superblock_security_struct *sbsec = sb->s_security; | |
2448 | ||
2449 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2450 | return 0; | |
2451 | ||
2452 | if (!data) | |
2453 | return 0; | |
2454 | ||
2455 | if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) | |
2456 | return 0; | |
2457 | ||
2458 | security_init_mnt_opts(&opts); | |
2459 | secdata = alloc_secdata(); | |
2460 | if (!secdata) | |
2461 | return -ENOMEM; | |
2462 | rc = selinux_sb_copy_data(data, secdata); | |
2463 | if (rc) | |
2464 | goto out_free_secdata; | |
2465 | ||
2466 | rc = selinux_parse_opts_str(secdata, &opts); | |
2467 | if (rc) | |
2468 | goto out_free_secdata; | |
2469 | ||
2470 | mount_options = opts.mnt_opts; | |
2471 | flags = opts.mnt_opts_flags; | |
2472 | ||
2473 | for (i = 0; i < opts.num_mnt_opts; i++) { | |
2474 | u32 sid; | |
2475 | size_t len; | |
2476 | ||
12f348b9 | 2477 | if (flags[i] == SBLABEL_MNT) |
026eb167 EP |
2478 | continue; |
2479 | len = strlen(mount_options[i]); | |
2480 | rc = security_context_to_sid(mount_options[i], len, &sid); | |
2481 | if (rc) { | |
2482 | printk(KERN_WARNING "SELinux: security_context_to_sid" | |
102aefdd AA |
2483 | "(%s) failed for (dev %s, type "SB_TYPE_FMT") errno=%d\n", |
2484 | mount_options[i], sb->s_id, SB_TYPE_ARGS(sb), rc); | |
026eb167 EP |
2485 | goto out_free_opts; |
2486 | } | |
2487 | rc = -EINVAL; | |
2488 | switch (flags[i]) { | |
2489 | case FSCONTEXT_MNT: | |
2490 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) | |
2491 | goto out_bad_option; | |
2492 | break; | |
2493 | case CONTEXT_MNT: | |
2494 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2495 | goto out_bad_option; | |
2496 | break; | |
2497 | case ROOTCONTEXT_MNT: { | |
2498 | struct inode_security_struct *root_isec; | |
2499 | root_isec = sb->s_root->d_inode->i_security; | |
2500 | ||
2501 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2502 | goto out_bad_option; | |
2503 | break; | |
2504 | } | |
2505 | case DEFCONTEXT_MNT: | |
2506 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2507 | goto out_bad_option; | |
2508 | break; | |
2509 | default: | |
2510 | goto out_free_opts; | |
2511 | } | |
2512 | } | |
2513 | ||
2514 | rc = 0; | |
2515 | out_free_opts: | |
2516 | security_free_mnt_opts(&opts); | |
2517 | out_free_secdata: | |
2518 | free_secdata(secdata); | |
2519 | return rc; | |
2520 | out_bad_option: | |
2521 | printk(KERN_WARNING "SELinux: unable to change security options " | |
102aefdd AA |
2522 | "during remount (dev %s, type "SB_TYPE_FMT")\n", sb->s_id, |
2523 | SB_TYPE_ARGS(sb)); | |
026eb167 EP |
2524 | goto out_free_opts; |
2525 | } | |
2526 | ||
12204e24 | 2527 | static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) |
1da177e4 | 2528 | { |
88e67f3b | 2529 | const struct cred *cred = current_cred(); |
2bf49690 | 2530 | struct common_audit_data ad; |
1da177e4 LT |
2531 | int rc; |
2532 | ||
2533 | rc = superblock_doinit(sb, data); | |
2534 | if (rc) | |
2535 | return rc; | |
2536 | ||
74192246 JM |
2537 | /* Allow all mounts performed by the kernel */ |
2538 | if (flags & MS_KERNMOUNT) | |
2539 | return 0; | |
2540 | ||
50c205f5 | 2541 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2542 | ad.u.dentry = sb->s_root; |
88e67f3b | 2543 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); |
1da177e4 LT |
2544 | } |
2545 | ||
726c3342 | 2546 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 | 2547 | { |
88e67f3b | 2548 | const struct cred *cred = current_cred(); |
2bf49690 | 2549 | struct common_audit_data ad; |
1da177e4 | 2550 | |
50c205f5 | 2551 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2552 | ad.u.dentry = dentry->d_sb->s_root; |
88e67f3b | 2553 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2554 | } |
2555 | ||
808d4e3c | 2556 | static int selinux_mount(const char *dev_name, |
b5266eb4 | 2557 | struct path *path, |
808d4e3c | 2558 | const char *type, |
828dfe1d EP |
2559 | unsigned long flags, |
2560 | void *data) | |
1da177e4 | 2561 | { |
88e67f3b | 2562 | const struct cred *cred = current_cred(); |
1da177e4 LT |
2563 | |
2564 | if (flags & MS_REMOUNT) | |
d8c9584e | 2565 | return superblock_has_perm(cred, path->dentry->d_sb, |
828dfe1d | 2566 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2567 | else |
2875fa00 | 2568 | return path_has_perm(cred, path, FILE__MOUNTON); |
1da177e4 LT |
2569 | } |
2570 | ||
2571 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2572 | { | |
88e67f3b | 2573 | const struct cred *cred = current_cred(); |
1da177e4 | 2574 | |
88e67f3b | 2575 | return superblock_has_perm(cred, mnt->mnt_sb, |
828dfe1d | 2576 | FILESYSTEM__UNMOUNT, NULL); |
1da177e4 LT |
2577 | } |
2578 | ||
2579 | /* inode security operations */ | |
2580 | ||
2581 | static int selinux_inode_alloc_security(struct inode *inode) | |
2582 | { | |
2583 | return inode_alloc_security(inode); | |
2584 | } | |
2585 | ||
2586 | static void selinux_inode_free_security(struct inode *inode) | |
2587 | { | |
2588 | inode_free_security(inode); | |
2589 | } | |
2590 | ||
d47be3df DQ |
2591 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, |
2592 | struct qstr *name, void **ctx, | |
2593 | u32 *ctxlen) | |
2594 | { | |
2595 | const struct cred *cred = current_cred(); | |
2596 | struct task_security_struct *tsec; | |
2597 | struct inode_security_struct *dsec; | |
2598 | struct superblock_security_struct *sbsec; | |
2599 | struct inode *dir = dentry->d_parent->d_inode; | |
2600 | u32 newsid; | |
2601 | int rc; | |
2602 | ||
2603 | tsec = cred->security; | |
2604 | dsec = dir->i_security; | |
2605 | sbsec = dir->i_sb->s_security; | |
2606 | ||
2607 | if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { | |
2608 | newsid = tsec->create_sid; | |
2609 | } else { | |
2610 | rc = security_transition_sid(tsec->sid, dsec->sid, | |
2611 | inode_mode_to_security_class(mode), | |
2612 | name, | |
2613 | &newsid); | |
2614 | if (rc) { | |
2615 | printk(KERN_WARNING | |
2616 | "%s: security_transition_sid failed, rc=%d\n", | |
2617 | __func__, -rc); | |
2618 | return rc; | |
2619 | } | |
2620 | } | |
2621 | ||
2622 | return security_sid_to_context(newsid, (char **)ctx, ctxlen); | |
2623 | } | |
2624 | ||
5e41ff9e | 2625 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
9548906b TH |
2626 | const struct qstr *qstr, |
2627 | const char **name, | |
2a7dba39 | 2628 | void **value, size_t *len) |
5e41ff9e | 2629 | { |
5fb49870 | 2630 | const struct task_security_struct *tsec = current_security(); |
5e41ff9e SS |
2631 | struct inode_security_struct *dsec; |
2632 | struct superblock_security_struct *sbsec; | |
275bb41e | 2633 | u32 sid, newsid, clen; |
5e41ff9e | 2634 | int rc; |
9548906b | 2635 | char *context; |
5e41ff9e | 2636 | |
5e41ff9e SS |
2637 | dsec = dir->i_security; |
2638 | sbsec = dir->i_sb->s_security; | |
5e41ff9e | 2639 | |
275bb41e DH |
2640 | sid = tsec->sid; |
2641 | newsid = tsec->create_sid; | |
2642 | ||
415103f9 EP |
2643 | if ((sbsec->flags & SE_SBINITIALIZED) && |
2644 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) | |
2645 | newsid = sbsec->mntpoint_sid; | |
12f348b9 | 2646 | else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) { |
275bb41e | 2647 | rc = security_transition_sid(sid, dsec->sid, |
5e41ff9e | 2648 | inode_mode_to_security_class(inode->i_mode), |
652bb9b0 | 2649 | qstr, &newsid); |
5e41ff9e SS |
2650 | if (rc) { |
2651 | printk(KERN_WARNING "%s: " | |
2652 | "security_transition_sid failed, rc=%d (dev=%s " | |
2653 | "ino=%ld)\n", | |
dd6f953a | 2654 | __func__, |
5e41ff9e SS |
2655 | -rc, inode->i_sb->s_id, inode->i_ino); |
2656 | return rc; | |
2657 | } | |
2658 | } | |
2659 | ||
296fddf7 | 2660 | /* Possibly defer initialization to selinux_complete_init. */ |
0d90a7ec | 2661 | if (sbsec->flags & SE_SBINITIALIZED) { |
296fddf7 EP |
2662 | struct inode_security_struct *isec = inode->i_security; |
2663 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
2664 | isec->sid = newsid; | |
2665 | isec->initialized = 1; | |
2666 | } | |
5e41ff9e | 2667 | |
12f348b9 | 2668 | if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT)) |
25a74f3b SS |
2669 | return -EOPNOTSUPP; |
2670 | ||
9548906b TH |
2671 | if (name) |
2672 | *name = XATTR_SELINUX_SUFFIX; | |
5e41ff9e | 2673 | |
570bc1c2 | 2674 | if (value && len) { |
12b29f34 | 2675 | rc = security_sid_to_context_force(newsid, &context, &clen); |
9548906b | 2676 | if (rc) |
570bc1c2 | 2677 | return rc; |
570bc1c2 SS |
2678 | *value = context; |
2679 | *len = clen; | |
5e41ff9e | 2680 | } |
5e41ff9e | 2681 | |
5e41ff9e SS |
2682 | return 0; |
2683 | } | |
2684 | ||
4acdaf27 | 2685 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) |
1da177e4 LT |
2686 | { |
2687 | return may_create(dir, dentry, SECCLASS_FILE); | |
2688 | } | |
2689 | ||
1da177e4 LT |
2690 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2691 | { | |
1da177e4 LT |
2692 | return may_link(dir, old_dentry, MAY_LINK); |
2693 | } | |
2694 | ||
1da177e4 LT |
2695 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2696 | { | |
1da177e4 LT |
2697 | return may_link(dir, dentry, MAY_UNLINK); |
2698 | } | |
2699 | ||
2700 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2701 | { | |
2702 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2703 | } | |
2704 | ||
18bb1db3 | 2705 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) |
1da177e4 LT |
2706 | { |
2707 | return may_create(dir, dentry, SECCLASS_DIR); | |
2708 | } | |
2709 | ||
1da177e4 LT |
2710 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2711 | { | |
2712 | return may_link(dir, dentry, MAY_RMDIR); | |
2713 | } | |
2714 | ||
1a67aafb | 2715 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
1da177e4 | 2716 | { |
1da177e4 LT |
2717 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); |
2718 | } | |
2719 | ||
1da177e4 | 2720 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 2721 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
2722 | { |
2723 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2724 | } | |
2725 | ||
1da177e4 LT |
2726 | static int selinux_inode_readlink(struct dentry *dentry) |
2727 | { | |
88e67f3b DH |
2728 | const struct cred *cred = current_cred(); |
2729 | ||
2875fa00 | 2730 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
2731 | } |
2732 | ||
2733 | static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) | |
2734 | { | |
88e67f3b | 2735 | const struct cred *cred = current_cred(); |
1da177e4 | 2736 | |
2875fa00 | 2737 | return dentry_has_perm(cred, dentry, FILE__READ); |
1da177e4 LT |
2738 | } |
2739 | ||
d4cf970d EP |
2740 | static noinline int audit_inode_permission(struct inode *inode, |
2741 | u32 perms, u32 audited, u32 denied, | |
2742 | unsigned flags) | |
1da177e4 | 2743 | { |
b782e0a6 | 2744 | struct common_audit_data ad; |
d4cf970d EP |
2745 | struct inode_security_struct *isec = inode->i_security; |
2746 | int rc; | |
2747 | ||
50c205f5 | 2748 | ad.type = LSM_AUDIT_DATA_INODE; |
d4cf970d EP |
2749 | ad.u.inode = inode; |
2750 | ||
2751 | rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, | |
2752 | audited, denied, &ad, flags); | |
2753 | if (rc) | |
2754 | return rc; | |
2755 | return 0; | |
2756 | } | |
2757 | ||
e74f71eb | 2758 | static int selinux_inode_permission(struct inode *inode, int mask) |
1da177e4 | 2759 | { |
88e67f3b | 2760 | const struct cred *cred = current_cred(); |
b782e0a6 EP |
2761 | u32 perms; |
2762 | bool from_access; | |
cf1dd1da | 2763 | unsigned flags = mask & MAY_NOT_BLOCK; |
2e334057 EP |
2764 | struct inode_security_struct *isec; |
2765 | u32 sid; | |
2766 | struct av_decision avd; | |
2767 | int rc, rc2; | |
2768 | u32 audited, denied; | |
1da177e4 | 2769 | |
b782e0a6 | 2770 | from_access = mask & MAY_ACCESS; |
d09ca739 EP |
2771 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
2772 | ||
b782e0a6 EP |
2773 | /* No permission to check. Existence test. */ |
2774 | if (!mask) | |
1da177e4 | 2775 | return 0; |
1da177e4 | 2776 | |
2e334057 | 2777 | validate_creds(cred); |
b782e0a6 | 2778 | |
2e334057 EP |
2779 | if (unlikely(IS_PRIVATE(inode))) |
2780 | return 0; | |
b782e0a6 EP |
2781 | |
2782 | perms = file_mask_to_av(inode->i_mode, mask); | |
2783 | ||
2e334057 EP |
2784 | sid = cred_sid(cred); |
2785 | isec = inode->i_security; | |
2786 | ||
2787 | rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd); | |
2788 | audited = avc_audit_required(perms, &avd, rc, | |
2789 | from_access ? FILE__AUDIT_ACCESS : 0, | |
2790 | &denied); | |
2791 | if (likely(!audited)) | |
2792 | return rc; | |
2793 | ||
d4cf970d | 2794 | rc2 = audit_inode_permission(inode, perms, audited, denied, flags); |
2e334057 EP |
2795 | if (rc2) |
2796 | return rc2; | |
2797 | return rc; | |
1da177e4 LT |
2798 | } |
2799 | ||
2800 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
2801 | { | |
88e67f3b | 2802 | const struct cred *cred = current_cred(); |
bc6a6008 | 2803 | unsigned int ia_valid = iattr->ia_valid; |
95dbf739 | 2804 | __u32 av = FILE__WRITE; |
1da177e4 | 2805 | |
bc6a6008 AW |
2806 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ |
2807 | if (ia_valid & ATTR_FORCE) { | |
2808 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
2809 | ATTR_FORCE); | |
2810 | if (!ia_valid) | |
2811 | return 0; | |
2812 | } | |
1da177e4 | 2813 | |
bc6a6008 AW |
2814 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | |
2815 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
2875fa00 | 2816 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
1da177e4 | 2817 | |
3d2195c3 | 2818 | if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE)) |
95dbf739 EP |
2819 | av |= FILE__OPEN; |
2820 | ||
2821 | return dentry_has_perm(cred, dentry, av); | |
1da177e4 LT |
2822 | } |
2823 | ||
2824 | static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) | |
2825 | { | |
88e67f3b | 2826 | const struct cred *cred = current_cred(); |
2875fa00 EP |
2827 | struct path path; |
2828 | ||
2829 | path.dentry = dentry; | |
2830 | path.mnt = mnt; | |
88e67f3b | 2831 | |
2875fa00 | 2832 | return path_has_perm(cred, &path, FILE__GETATTR); |
1da177e4 LT |
2833 | } |
2834 | ||
8f0cfa52 | 2835 | static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) |
b5376771 | 2836 | { |
88e67f3b DH |
2837 | const struct cred *cred = current_cred(); |
2838 | ||
b5376771 SH |
2839 | if (!strncmp(name, XATTR_SECURITY_PREFIX, |
2840 | sizeof XATTR_SECURITY_PREFIX - 1)) { | |
2841 | if (!strcmp(name, XATTR_NAME_CAPS)) { | |
2842 | if (!capable(CAP_SETFCAP)) | |
2843 | return -EPERM; | |
2844 | } else if (!capable(CAP_SYS_ADMIN)) { | |
2845 | /* A different attribute in the security namespace. | |
2846 | Restrict to administrator. */ | |
2847 | return -EPERM; | |
2848 | } | |
2849 | } | |
2850 | ||
2851 | /* Not an attribute we recognize, so just check the | |
2852 | ordinary setattr permission. */ | |
2875fa00 | 2853 | return dentry_has_perm(cred, dentry, FILE__SETATTR); |
b5376771 SH |
2854 | } |
2855 | ||
8f0cfa52 DH |
2856 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
2857 | const void *value, size_t size, int flags) | |
1da177e4 | 2858 | { |
1da177e4 LT |
2859 | struct inode *inode = dentry->d_inode; |
2860 | struct inode_security_struct *isec = inode->i_security; | |
2861 | struct superblock_security_struct *sbsec; | |
2bf49690 | 2862 | struct common_audit_data ad; |
275bb41e | 2863 | u32 newsid, sid = current_sid(); |
1da177e4 LT |
2864 | int rc = 0; |
2865 | ||
b5376771 SH |
2866 | if (strcmp(name, XATTR_NAME_SELINUX)) |
2867 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
2868 | |
2869 | sbsec = inode->i_sb->s_security; | |
12f348b9 | 2870 | if (!(sbsec->flags & SBLABEL_MNT)) |
1da177e4 LT |
2871 | return -EOPNOTSUPP; |
2872 | ||
2e149670 | 2873 | if (!inode_owner_or_capable(inode)) |
1da177e4 LT |
2874 | return -EPERM; |
2875 | ||
50c205f5 | 2876 | ad.type = LSM_AUDIT_DATA_DENTRY; |
a269434d | 2877 | ad.u.dentry = dentry; |
1da177e4 | 2878 | |
275bb41e | 2879 | rc = avc_has_perm(sid, isec->sid, isec->sclass, |
1da177e4 LT |
2880 | FILE__RELABELFROM, &ad); |
2881 | if (rc) | |
2882 | return rc; | |
2883 | ||
2884 | rc = security_context_to_sid(value, size, &newsid); | |
12b29f34 | 2885 | if (rc == -EINVAL) { |
d6ea83ec EP |
2886 | if (!capable(CAP_MAC_ADMIN)) { |
2887 | struct audit_buffer *ab; | |
2888 | size_t audit_size; | |
2889 | const char *str; | |
2890 | ||
2891 | /* We strip a nul only if it is at the end, otherwise the | |
2892 | * context contains a nul and we should audit that */ | |
e3fea3f7 AV |
2893 | if (value) { |
2894 | str = value; | |
2895 | if (str[size - 1] == '\0') | |
2896 | audit_size = size - 1; | |
2897 | else | |
2898 | audit_size = size; | |
2899 | } else { | |
2900 | str = ""; | |
2901 | audit_size = 0; | |
2902 | } | |
d6ea83ec EP |
2903 | ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); |
2904 | audit_log_format(ab, "op=setxattr invalid_context="); | |
2905 | audit_log_n_untrustedstring(ab, value, audit_size); | |
2906 | audit_log_end(ab); | |
2907 | ||
12b29f34 | 2908 | return rc; |
d6ea83ec | 2909 | } |
12b29f34 SS |
2910 | rc = security_context_to_sid_force(value, size, &newsid); |
2911 | } | |
1da177e4 LT |
2912 | if (rc) |
2913 | return rc; | |
2914 | ||
275bb41e | 2915 | rc = avc_has_perm(sid, newsid, isec->sclass, |
1da177e4 LT |
2916 | FILE__RELABELTO, &ad); |
2917 | if (rc) | |
2918 | return rc; | |
2919 | ||
275bb41e | 2920 | rc = security_validate_transition(isec->sid, newsid, sid, |
828dfe1d | 2921 | isec->sclass); |
1da177e4 LT |
2922 | if (rc) |
2923 | return rc; | |
2924 | ||
2925 | return avc_has_perm(newsid, | |
2926 | sbsec->sid, | |
2927 | SECCLASS_FILESYSTEM, | |
2928 | FILESYSTEM__ASSOCIATE, | |
2929 | &ad); | |
2930 | } | |
2931 | ||
8f0cfa52 | 2932 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 2933 | const void *value, size_t size, |
8f0cfa52 | 2934 | int flags) |
1da177e4 LT |
2935 | { |
2936 | struct inode *inode = dentry->d_inode; | |
2937 | struct inode_security_struct *isec = inode->i_security; | |
2938 | u32 newsid; | |
2939 | int rc; | |
2940 | ||
2941 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
2942 | /* Not an attribute we recognize, so nothing to do. */ | |
2943 | return; | |
2944 | } | |
2945 | ||
12b29f34 | 2946 | rc = security_context_to_sid_force(value, size, &newsid); |
1da177e4 | 2947 | if (rc) { |
12b29f34 SS |
2948 | printk(KERN_ERR "SELinux: unable to map context to SID" |
2949 | "for (%s, %lu), rc=%d\n", | |
2950 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
2951 | return; |
2952 | } | |
2953 | ||
aa9c2669 | 2954 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 2955 | isec->sid = newsid; |
aa9c2669 DQ |
2956 | isec->initialized = 1; |
2957 | ||
1da177e4 LT |
2958 | return; |
2959 | } | |
2960 | ||
8f0cfa52 | 2961 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 2962 | { |
88e67f3b DH |
2963 | const struct cred *cred = current_cred(); |
2964 | ||
2875fa00 | 2965 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
2966 | } |
2967 | ||
828dfe1d | 2968 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 | 2969 | { |
88e67f3b DH |
2970 | const struct cred *cred = current_cred(); |
2971 | ||
2875fa00 | 2972 | return dentry_has_perm(cred, dentry, FILE__GETATTR); |
1da177e4 LT |
2973 | } |
2974 | ||
8f0cfa52 | 2975 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 2976 | { |
b5376771 SH |
2977 | if (strcmp(name, XATTR_NAME_SELINUX)) |
2978 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
2979 | |
2980 | /* No one is allowed to remove a SELinux security label. | |
2981 | You can change the label, but all data must be labeled. */ | |
2982 | return -EACCES; | |
2983 | } | |
2984 | ||
d381d8a9 | 2985 | /* |
abc69bb6 | 2986 | * Copy the inode security context value to the user. |
d381d8a9 JM |
2987 | * |
2988 | * Permission check is handled by selinux_inode_getxattr hook. | |
2989 | */ | |
42492594 | 2990 | static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 2991 | { |
42492594 DQ |
2992 | u32 size; |
2993 | int error; | |
2994 | char *context = NULL; | |
1da177e4 | 2995 | struct inode_security_struct *isec = inode->i_security; |
d381d8a9 | 2996 | |
8c8570fb DK |
2997 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
2998 | return -EOPNOTSUPP; | |
d381d8a9 | 2999 | |
abc69bb6 SS |
3000 | /* |
3001 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3002 | * value even if it is not defined by current policy; otherwise, | |
3003 | * use the in-core value under current policy. | |
3004 | * Use the non-auditing forms of the permission checks since | |
3005 | * getxattr may be called by unprivileged processes commonly | |
3006 | * and lack of permission just means that we fall back to the | |
3007 | * in-core context value, not a denial. | |
3008 | */ | |
6a9de491 | 3009 | error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN, |
3699c53c | 3010 | SECURITY_CAP_NOAUDIT); |
abc69bb6 SS |
3011 | if (!error) |
3012 | error = security_sid_to_context_force(isec->sid, &context, | |
3013 | &size); | |
3014 | else | |
3015 | error = security_sid_to_context(isec->sid, &context, &size); | |
42492594 DQ |
3016 | if (error) |
3017 | return error; | |
3018 | error = size; | |
3019 | if (alloc) { | |
3020 | *buffer = context; | |
3021 | goto out_nofree; | |
3022 | } | |
3023 | kfree(context); | |
3024 | out_nofree: | |
3025 | return error; | |
1da177e4 LT |
3026 | } |
3027 | ||
3028 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 3029 | const void *value, size_t size, int flags) |
1da177e4 LT |
3030 | { |
3031 | struct inode_security_struct *isec = inode->i_security; | |
3032 | u32 newsid; | |
3033 | int rc; | |
3034 | ||
3035 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3036 | return -EOPNOTSUPP; | |
3037 | ||
3038 | if (!value || !size) | |
3039 | return -EACCES; | |
3040 | ||
828dfe1d | 3041 | rc = security_context_to_sid((void *)value, size, &newsid); |
1da177e4 LT |
3042 | if (rc) |
3043 | return rc; | |
3044 | ||
aa9c2669 | 3045 | isec->sclass = inode_mode_to_security_class(inode->i_mode); |
1da177e4 | 3046 | isec->sid = newsid; |
ddd29ec6 | 3047 | isec->initialized = 1; |
1da177e4 LT |
3048 | return 0; |
3049 | } | |
3050 | ||
3051 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3052 | { | |
3053 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3054 | if (buffer && len <= buffer_size) | |
3055 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3056 | return len; | |
3057 | } | |
3058 | ||
713a04ae AD |
3059 | static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) |
3060 | { | |
3061 | struct inode_security_struct *isec = inode->i_security; | |
3062 | *secid = isec->sid; | |
3063 | } | |
3064 | ||
1da177e4 LT |
3065 | /* file security operations */ |
3066 | ||
788e7dd4 | 3067 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 3068 | { |
88e67f3b | 3069 | const struct cred *cred = current_cred(); |
496ad9aa | 3070 | struct inode *inode = file_inode(file); |
1da177e4 | 3071 | |
1da177e4 LT |
3072 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ |
3073 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3074 | mask |= MAY_APPEND; | |
3075 | ||
389fb800 PM |
3076 | return file_has_perm(cred, file, |
3077 | file_mask_to_av(inode->i_mode, mask)); | |
1da177e4 LT |
3078 | } |
3079 | ||
788e7dd4 YN |
3080 | static int selinux_file_permission(struct file *file, int mask) |
3081 | { | |
496ad9aa | 3082 | struct inode *inode = file_inode(file); |
20dda18b SS |
3083 | struct file_security_struct *fsec = file->f_security; |
3084 | struct inode_security_struct *isec = inode->i_security; | |
3085 | u32 sid = current_sid(); | |
3086 | ||
389fb800 | 3087 | if (!mask) |
788e7dd4 YN |
3088 | /* No permission to check. Existence test. */ |
3089 | return 0; | |
788e7dd4 | 3090 | |
20dda18b SS |
3091 | if (sid == fsec->sid && fsec->isid == isec->sid && |
3092 | fsec->pseqno == avc_policy_seqno()) | |
83d49856 | 3093 | /* No change since file_open check. */ |
20dda18b SS |
3094 | return 0; |
3095 | ||
788e7dd4 YN |
3096 | return selinux_revalidate_file_permission(file, mask); |
3097 | } | |
3098 | ||
1da177e4 LT |
3099 | static int selinux_file_alloc_security(struct file *file) |
3100 | { | |
3101 | return file_alloc_security(file); | |
3102 | } | |
3103 | ||
3104 | static void selinux_file_free_security(struct file *file) | |
3105 | { | |
3106 | file_free_security(file); | |
3107 | } | |
3108 | ||
3109 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, | |
3110 | unsigned long arg) | |
3111 | { | |
88e67f3b | 3112 | const struct cred *cred = current_cred(); |
0b24dcb7 | 3113 | int error = 0; |
1da177e4 | 3114 | |
0b24dcb7 EP |
3115 | switch (cmd) { |
3116 | case FIONREAD: | |
3117 | /* fall through */ | |
3118 | case FIBMAP: | |
3119 | /* fall through */ | |
3120 | case FIGETBSZ: | |
3121 | /* fall through */ | |
2f99c369 | 3122 | case FS_IOC_GETFLAGS: |
0b24dcb7 | 3123 | /* fall through */ |
2f99c369 | 3124 | case FS_IOC_GETVERSION: |
0b24dcb7 EP |
3125 | error = file_has_perm(cred, file, FILE__GETATTR); |
3126 | break; | |
1da177e4 | 3127 | |
2f99c369 | 3128 | case FS_IOC_SETFLAGS: |
0b24dcb7 | 3129 | /* fall through */ |
2f99c369 | 3130 | case FS_IOC_SETVERSION: |
0b24dcb7 EP |
3131 | error = file_has_perm(cred, file, FILE__SETATTR); |
3132 | break; | |
3133 | ||
3134 | /* sys_ioctl() checks */ | |
3135 | case FIONBIO: | |
3136 | /* fall through */ | |
3137 | case FIOASYNC: | |
3138 | error = file_has_perm(cred, file, 0); | |
3139 | break; | |
1da177e4 | 3140 | |
0b24dcb7 EP |
3141 | case KDSKBENT: |
3142 | case KDSKBSENT: | |
6a9de491 EP |
3143 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, |
3144 | SECURITY_CAP_AUDIT); | |
0b24dcb7 EP |
3145 | break; |
3146 | ||
3147 | /* default case assumes that the command will go | |
3148 | * to the file's ioctl() function. | |
3149 | */ | |
3150 | default: | |
3151 | error = file_has_perm(cred, file, FILE__IOCTL); | |
3152 | } | |
3153 | return error; | |
1da177e4 LT |
3154 | } |
3155 | ||
fcaaade1 SS |
3156 | static int default_noexec; |
3157 | ||
1da177e4 LT |
3158 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) |
3159 | { | |
88e67f3b | 3160 | const struct cred *cred = current_cred(); |
d84f4f99 | 3161 | int rc = 0; |
88e67f3b | 3162 | |
fcaaade1 SS |
3163 | if (default_noexec && |
3164 | (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { | |
1da177e4 LT |
3165 | /* |
3166 | * We are making executable an anonymous mapping or a | |
3167 | * private file mapping that will also be writable. | |
3168 | * This has an additional check. | |
3169 | */ | |
d84f4f99 | 3170 | rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); |
1da177e4 | 3171 | if (rc) |
d84f4f99 | 3172 | goto error; |
1da177e4 | 3173 | } |
1da177e4 LT |
3174 | |
3175 | if (file) { | |
3176 | /* read access is always possible with a mapping */ | |
3177 | u32 av = FILE__READ; | |
3178 | ||
3179 | /* write access only matters if the mapping is shared */ | |
3180 | if (shared && (prot & PROT_WRITE)) | |
3181 | av |= FILE__WRITE; | |
3182 | ||
3183 | if (prot & PROT_EXEC) | |
3184 | av |= FILE__EXECUTE; | |
3185 | ||
88e67f3b | 3186 | return file_has_perm(cred, file, av); |
1da177e4 | 3187 | } |
d84f4f99 DH |
3188 | |
3189 | error: | |
3190 | return rc; | |
1da177e4 LT |
3191 | } |
3192 | ||
e5467859 | 3193 | static int selinux_mmap_addr(unsigned long addr) |
1da177e4 | 3194 | { |
ed032189 | 3195 | int rc = 0; |
275bb41e | 3196 | u32 sid = current_sid(); |
1da177e4 | 3197 | |
84336d1a EP |
3198 | /* |
3199 | * notice that we are intentionally putting the SELinux check before | |
3200 | * the secondary cap_file_mmap check. This is such a likely attempt | |
3201 | * at bad behaviour/exploit that we always want to get the AVC, even | |
3202 | * if DAC would have also denied the operation. | |
3203 | */ | |
a2551df7 | 3204 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { |
ed032189 EP |
3205 | rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, |
3206 | MEMPROTECT__MMAP_ZERO, NULL); | |
84336d1a EP |
3207 | if (rc) |
3208 | return rc; | |
3209 | } | |
3210 | ||
3211 | /* do DAC check on address space usage */ | |
e5467859 AV |
3212 | return cap_mmap_addr(addr); |
3213 | } | |
1da177e4 | 3214 | |
e5467859 AV |
3215 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, |
3216 | unsigned long prot, unsigned long flags) | |
3217 | { | |
1da177e4 LT |
3218 | if (selinux_checkreqprot) |
3219 | prot = reqprot; | |
3220 | ||
3221 | return file_map_prot_check(file, prot, | |
3222 | (flags & MAP_TYPE) == MAP_SHARED); | |
3223 | } | |
3224 | ||
3225 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3226 | unsigned long reqprot, | |
3227 | unsigned long prot) | |
3228 | { | |
88e67f3b | 3229 | const struct cred *cred = current_cred(); |
1da177e4 LT |
3230 | |
3231 | if (selinux_checkreqprot) | |
3232 | prot = reqprot; | |
3233 | ||
fcaaade1 SS |
3234 | if (default_noexec && |
3235 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
d541bbee | 3236 | int rc = 0; |
db4c9641 SS |
3237 | if (vma->vm_start >= vma->vm_mm->start_brk && |
3238 | vma->vm_end <= vma->vm_mm->brk) { | |
d84f4f99 | 3239 | rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); |
db4c9641 SS |
3240 | } else if (!vma->vm_file && |
3241 | vma->vm_start <= vma->vm_mm->start_stack && | |
3242 | vma->vm_end >= vma->vm_mm->start_stack) { | |
3b11a1de | 3243 | rc = current_has_perm(current, PROCESS__EXECSTACK); |
db4c9641 SS |
3244 | } else if (vma->vm_file && vma->anon_vma) { |
3245 | /* | |
3246 | * We are making executable a file mapping that has | |
3247 | * had some COW done. Since pages might have been | |
3248 | * written, check ability to execute the possibly | |
3249 | * modified content. This typically should only | |
3250 | * occur for text relocations. | |
3251 | */ | |
d84f4f99 | 3252 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); |
db4c9641 | 3253 | } |