Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * NSA Security-Enhanced Linux (SELinux) security module | |
3 | * | |
4 | * This file contains the SELinux hook function implementations. | |
5 | * | |
6 | * Authors: Stephen Smalley, <sds@epoch.ncsc.mil> | |
7 | * Chris Vance, <cvance@nai.com> | |
8 | * Wayne Salamon, <wsalamon@nai.com> | |
9 | * James Morris <jmorris@redhat.com> | |
10 | * | |
11 | * Copyright (C) 2001,2002 Networks Associates Technology, Inc. | |
12 | * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com> | |
13 | * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. | |
14 | * <dgoeddel@trustedcs.com> | |
15 | * | |
16 | * This program is free software; you can redistribute it and/or modify | |
17 | * it under the terms of the GNU General Public License version 2, | |
18 | * as published by the Free Software Foundation. | |
19 | */ | |
20 | ||
21 | #include <linux/config.h> | |
22 | #include <linux/module.h> | |
23 | #include <linux/init.h> | |
24 | #include <linux/kernel.h> | |
25 | #include <linux/ptrace.h> | |
26 | #include <linux/errno.h> | |
27 | #include <linux/sched.h> | |
28 | #include <linux/security.h> | |
29 | #include <linux/xattr.h> | |
30 | #include <linux/capability.h> | |
31 | #include <linux/unistd.h> | |
32 | #include <linux/mm.h> | |
33 | #include <linux/mman.h> | |
34 | #include <linux/slab.h> | |
35 | #include <linux/pagemap.h> | |
36 | #include <linux/swap.h> | |
37 | #include <linux/smp_lock.h> | |
38 | #include <linux/spinlock.h> | |
39 | #include <linux/syscalls.h> | |
40 | #include <linux/file.h> | |
41 | #include <linux/namei.h> | |
42 | #include <linux/mount.h> | |
43 | #include <linux/ext2_fs.h> | |
44 | #include <linux/proc_fs.h> | |
45 | #include <linux/kd.h> | |
46 | #include <linux/netfilter_ipv4.h> | |
47 | #include <linux/netfilter_ipv6.h> | |
48 | #include <linux/tty.h> | |
49 | #include <net/icmp.h> | |
50 | #include <net/ip.h> /* for sysctl_local_port_range[] */ | |
51 | #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ | |
52 | #include <asm/uaccess.h> | |
53 | #include <asm/semaphore.h> | |
54 | #include <asm/ioctls.h> | |
55 | #include <linux/bitops.h> | |
56 | #include <linux/interrupt.h> | |
57 | #include <linux/netdevice.h> /* for network interface checks */ | |
58 | #include <linux/netlink.h> | |
59 | #include <linux/tcp.h> | |
60 | #include <linux/udp.h> | |
61 | #include <linux/quota.h> | |
62 | #include <linux/un.h> /* for Unix socket types */ | |
63 | #include <net/af_unix.h> /* for Unix socket types */ | |
64 | #include <linux/parser.h> | |
65 | #include <linux/nfs_mount.h> | |
66 | #include <net/ipv6.h> | |
67 | #include <linux/hugetlb.h> | |
68 | #include <linux/personality.h> | |
69 | #include <linux/sysctl.h> | |
70 | #include <linux/audit.h> | |
6931dfc9 | 71 | #include <linux/string.h> |
1da177e4 LT |
72 | |
73 | #include "avc.h" | |
74 | #include "objsec.h" | |
75 | #include "netif.h" | |
d28d1e08 | 76 | #include "xfrm.h" |
1da177e4 LT |
77 | |
78 | #define XATTR_SELINUX_SUFFIX "selinux" | |
79 | #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX | |
80 | ||
81 | extern unsigned int policydb_loaded_version; | |
82 | extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); | |
83 | ||
84 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP | |
85 | int selinux_enforcing = 0; | |
86 | ||
87 | static int __init enforcing_setup(char *str) | |
88 | { | |
89 | selinux_enforcing = simple_strtol(str,NULL,0); | |
90 | return 1; | |
91 | } | |
92 | __setup("enforcing=", enforcing_setup); | |
93 | #endif | |
94 | ||
95 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM | |
96 | int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; | |
97 | ||
98 | static int __init selinux_enabled_setup(char *str) | |
99 | { | |
100 | selinux_enabled = simple_strtol(str, NULL, 0); | |
101 | return 1; | |
102 | } | |
103 | __setup("selinux=", selinux_enabled_setup); | |
104 | #endif | |
105 | ||
106 | /* Original (dummy) security module. */ | |
107 | static struct security_operations *original_ops = NULL; | |
108 | ||
109 | /* Minimal support for a secondary security module, | |
110 | just to allow the use of the dummy or capability modules. | |
111 | The owlsm module can alternatively be used as a secondary | |
112 | module as long as CONFIG_OWLSM_FD is not enabled. */ | |
113 | static struct security_operations *secondary_ops = NULL; | |
114 | ||
115 | /* Lists of inode and superblock security structures initialized | |
116 | before the policy was loaded. */ | |
117 | static LIST_HEAD(superblock_security_head); | |
118 | static DEFINE_SPINLOCK(sb_security_lock); | |
119 | ||
120 | /* Allocate and free functions for each kind of security blob. */ | |
121 | ||
122 | static int task_alloc_security(struct task_struct *task) | |
123 | { | |
124 | struct task_security_struct *tsec; | |
125 | ||
89d155ef | 126 | tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); |
1da177e4 LT |
127 | if (!tsec) |
128 | return -ENOMEM; | |
129 | ||
1da177e4 LT |
130 | tsec->task = task; |
131 | tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED; | |
132 | task->security = tsec; | |
133 | ||
134 | return 0; | |
135 | } | |
136 | ||
137 | static void task_free_security(struct task_struct *task) | |
138 | { | |
139 | struct task_security_struct *tsec = task->security; | |
1da177e4 LT |
140 | task->security = NULL; |
141 | kfree(tsec); | |
142 | } | |
143 | ||
144 | static int inode_alloc_security(struct inode *inode) | |
145 | { | |
146 | struct task_security_struct *tsec = current->security; | |
147 | struct inode_security_struct *isec; | |
148 | ||
89d155ef | 149 | isec = kzalloc(sizeof(struct inode_security_struct), GFP_KERNEL); |
1da177e4 LT |
150 | if (!isec) |
151 | return -ENOMEM; | |
152 | ||
1da177e4 LT |
153 | init_MUTEX(&isec->sem); |
154 | INIT_LIST_HEAD(&isec->list); | |
1da177e4 LT |
155 | isec->inode = inode; |
156 | isec->sid = SECINITSID_UNLABELED; | |
157 | isec->sclass = SECCLASS_FILE; | |
9ac49d22 | 158 | isec->task_sid = tsec->sid; |
1da177e4 LT |
159 | inode->i_security = isec; |
160 | ||
161 | return 0; | |
162 | } | |
163 | ||
164 | static void inode_free_security(struct inode *inode) | |
165 | { | |
166 | struct inode_security_struct *isec = inode->i_security; | |
167 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
168 | ||
1da177e4 LT |
169 | spin_lock(&sbsec->isec_lock); |
170 | if (!list_empty(&isec->list)) | |
171 | list_del_init(&isec->list); | |
172 | spin_unlock(&sbsec->isec_lock); | |
173 | ||
174 | inode->i_security = NULL; | |
175 | kfree(isec); | |
176 | } | |
177 | ||
178 | static int file_alloc_security(struct file *file) | |
179 | { | |
180 | struct task_security_struct *tsec = current->security; | |
181 | struct file_security_struct *fsec; | |
182 | ||
26d2a4be | 183 | fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); |
1da177e4 LT |
184 | if (!fsec) |
185 | return -ENOMEM; | |
186 | ||
1da177e4 | 187 | fsec->file = file; |
9ac49d22 SS |
188 | fsec->sid = tsec->sid; |
189 | fsec->fown_sid = tsec->sid; | |
1da177e4 LT |
190 | file->f_security = fsec; |
191 | ||
192 | return 0; | |
193 | } | |
194 | ||
195 | static void file_free_security(struct file *file) | |
196 | { | |
197 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 LT |
198 | file->f_security = NULL; |
199 | kfree(fsec); | |
200 | } | |
201 | ||
202 | static int superblock_alloc_security(struct super_block *sb) | |
203 | { | |
204 | struct superblock_security_struct *sbsec; | |
205 | ||
89d155ef | 206 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
207 | if (!sbsec) |
208 | return -ENOMEM; | |
209 | ||
1da177e4 LT |
210 | init_MUTEX(&sbsec->sem); |
211 | INIT_LIST_HEAD(&sbsec->list); | |
212 | INIT_LIST_HEAD(&sbsec->isec_head); | |
213 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
214 | sbsec->sb = sb; |
215 | sbsec->sid = SECINITSID_UNLABELED; | |
216 | sbsec->def_sid = SECINITSID_FILE; | |
217 | sb->s_security = sbsec; | |
218 | ||
219 | return 0; | |
220 | } | |
221 | ||
222 | static void superblock_free_security(struct super_block *sb) | |
223 | { | |
224 | struct superblock_security_struct *sbsec = sb->s_security; | |
225 | ||
1da177e4 LT |
226 | spin_lock(&sb_security_lock); |
227 | if (!list_empty(&sbsec->list)) | |
228 | list_del_init(&sbsec->list); | |
229 | spin_unlock(&sb_security_lock); | |
230 | ||
231 | sb->s_security = NULL; | |
232 | kfree(sbsec); | |
233 | } | |
234 | ||
7d877f3b | 235 | static int sk_alloc_security(struct sock *sk, int family, gfp_t priority) |
1da177e4 LT |
236 | { |
237 | struct sk_security_struct *ssec; | |
238 | ||
239 | if (family != PF_UNIX) | |
240 | return 0; | |
241 | ||
89d155ef | 242 | ssec = kzalloc(sizeof(*ssec), priority); |
1da177e4 LT |
243 | if (!ssec) |
244 | return -ENOMEM; | |
245 | ||
1da177e4 LT |
246 | ssec->sk = sk; |
247 | ssec->peer_sid = SECINITSID_UNLABELED; | |
248 | sk->sk_security = ssec; | |
249 | ||
250 | return 0; | |
251 | } | |
252 | ||
253 | static void sk_free_security(struct sock *sk) | |
254 | { | |
255 | struct sk_security_struct *ssec = sk->sk_security; | |
256 | ||
9ac49d22 | 257 | if (sk->sk_family != PF_UNIX) |
1da177e4 LT |
258 | return; |
259 | ||
260 | sk->sk_security = NULL; | |
261 | kfree(ssec); | |
262 | } | |
1da177e4 LT |
263 | |
264 | /* The security server must be initialized before | |
265 | any labeling or access decisions can be provided. */ | |
266 | extern int ss_initialized; | |
267 | ||
268 | /* The file system's label must be initialized prior to use. */ | |
269 | ||
270 | static char *labeling_behaviors[6] = { | |
271 | "uses xattr", | |
272 | "uses transition SIDs", | |
273 | "uses task SIDs", | |
274 | "uses genfs_contexts", | |
275 | "not configured for labeling", | |
276 | "uses mountpoint labeling", | |
277 | }; | |
278 | ||
279 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); | |
280 | ||
281 | static inline int inode_doinit(struct inode *inode) | |
282 | { | |
283 | return inode_doinit_with_dentry(inode, NULL); | |
284 | } | |
285 | ||
286 | enum { | |
287 | Opt_context = 1, | |
288 | Opt_fscontext = 2, | |
289 | Opt_defcontext = 4, | |
290 | }; | |
291 | ||
292 | static match_table_t tokens = { | |
293 | {Opt_context, "context=%s"}, | |
294 | {Opt_fscontext, "fscontext=%s"}, | |
295 | {Opt_defcontext, "defcontext=%s"}, | |
296 | }; | |
297 | ||
298 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
299 | ||
300 | static int try_context_mount(struct super_block *sb, void *data) | |
301 | { | |
302 | char *context = NULL, *defcontext = NULL; | |
303 | const char *name; | |
304 | u32 sid; | |
305 | int alloc = 0, rc = 0, seen = 0; | |
306 | struct task_security_struct *tsec = current->security; | |
307 | struct superblock_security_struct *sbsec = sb->s_security; | |
308 | ||
309 | if (!data) | |
310 | goto out; | |
311 | ||
312 | name = sb->s_type->name; | |
313 | ||
314 | if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) { | |
315 | ||
316 | /* NFS we understand. */ | |
317 | if (!strcmp(name, "nfs")) { | |
318 | struct nfs_mount_data *d = data; | |
319 | ||
320 | if (d->version < NFS_MOUNT_VERSION) | |
321 | goto out; | |
322 | ||
323 | if (d->context[0]) { | |
324 | context = d->context; | |
325 | seen |= Opt_context; | |
326 | } | |
327 | } else | |
328 | goto out; | |
329 | ||
330 | } else { | |
331 | /* Standard string-based options. */ | |
332 | char *p, *options = data; | |
333 | ||
334 | while ((p = strsep(&options, ",")) != NULL) { | |
335 | int token; | |
336 | substring_t args[MAX_OPT_ARGS]; | |
337 | ||
338 | if (!*p) | |
339 | continue; | |
340 | ||
341 | token = match_token(p, tokens, args); | |
342 | ||
343 | switch (token) { | |
344 | case Opt_context: | |
345 | if (seen) { | |
346 | rc = -EINVAL; | |
347 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
348 | goto out_free; | |
349 | } | |
350 | context = match_strdup(&args[0]); | |
351 | if (!context) { | |
352 | rc = -ENOMEM; | |
353 | goto out_free; | |
354 | } | |
355 | if (!alloc) | |
356 | alloc = 1; | |
357 | seen |= Opt_context; | |
358 | break; | |
359 | ||
360 | case Opt_fscontext: | |
361 | if (seen & (Opt_context|Opt_fscontext)) { | |
362 | rc = -EINVAL; | |
363 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
364 | goto out_free; | |
365 | } | |
366 | context = match_strdup(&args[0]); | |
367 | if (!context) { | |
368 | rc = -ENOMEM; | |
369 | goto out_free; | |
370 | } | |
371 | if (!alloc) | |
372 | alloc = 1; | |
373 | seen |= Opt_fscontext; | |
374 | break; | |
375 | ||
376 | case Opt_defcontext: | |
377 | if (sbsec->behavior != SECURITY_FS_USE_XATTR) { | |
378 | rc = -EINVAL; | |
379 | printk(KERN_WARNING "SELinux: " | |
380 | "defcontext option is invalid " | |
381 | "for this filesystem type\n"); | |
382 | goto out_free; | |
383 | } | |
384 | if (seen & (Opt_context|Opt_defcontext)) { | |
385 | rc = -EINVAL; | |
386 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
387 | goto out_free; | |
388 | } | |
389 | defcontext = match_strdup(&args[0]); | |
390 | if (!defcontext) { | |
391 | rc = -ENOMEM; | |
392 | goto out_free; | |
393 | } | |
394 | if (!alloc) | |
395 | alloc = 1; | |
396 | seen |= Opt_defcontext; | |
397 | break; | |
398 | ||
399 | default: | |
400 | rc = -EINVAL; | |
401 | printk(KERN_WARNING "SELinux: unknown mount " | |
402 | "option\n"); | |
403 | goto out_free; | |
404 | ||
405 | } | |
406 | } | |
407 | } | |
408 | ||
409 | if (!seen) | |
410 | goto out; | |
411 | ||
412 | if (context) { | |
413 | rc = security_context_to_sid(context, strlen(context), &sid); | |
414 | if (rc) { | |
415 | printk(KERN_WARNING "SELinux: security_context_to_sid" | |
416 | "(%s) failed for (dev %s, type %s) errno=%d\n", | |
417 | context, sb->s_id, name, rc); | |
418 | goto out_free; | |
419 | } | |
420 | ||
421 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
422 | FILESYSTEM__RELABELFROM, NULL); | |
423 | if (rc) | |
424 | goto out_free; | |
425 | ||
426 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, | |
427 | FILESYSTEM__RELABELTO, NULL); | |
428 | if (rc) | |
429 | goto out_free; | |
430 | ||
431 | sbsec->sid = sid; | |
432 | ||
433 | if (seen & Opt_context) | |
434 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; | |
435 | } | |
436 | ||
437 | if (defcontext) { | |
438 | rc = security_context_to_sid(defcontext, strlen(defcontext), &sid); | |
439 | if (rc) { | |
440 | printk(KERN_WARNING "SELinux: security_context_to_sid" | |
441 | "(%s) failed for (dev %s, type %s) errno=%d\n", | |
442 | defcontext, sb->s_id, name, rc); | |
443 | goto out_free; | |
444 | } | |
445 | ||
446 | if (sid == sbsec->def_sid) | |
447 | goto out_free; | |
448 | ||
449 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
450 | FILESYSTEM__RELABELFROM, NULL); | |
451 | if (rc) | |
452 | goto out_free; | |
453 | ||
454 | rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
455 | FILESYSTEM__ASSOCIATE, NULL); | |
456 | if (rc) | |
457 | goto out_free; | |
458 | ||
459 | sbsec->def_sid = sid; | |
460 | } | |
461 | ||
462 | out_free: | |
463 | if (alloc) { | |
464 | kfree(context); | |
465 | kfree(defcontext); | |
466 | } | |
467 | out: | |
468 | return rc; | |
469 | } | |
470 | ||
471 | static int superblock_doinit(struct super_block *sb, void *data) | |
472 | { | |
473 | struct superblock_security_struct *sbsec = sb->s_security; | |
474 | struct dentry *root = sb->s_root; | |
475 | struct inode *inode = root->d_inode; | |
476 | int rc = 0; | |
477 | ||
478 | down(&sbsec->sem); | |
479 | if (sbsec->initialized) | |
480 | goto out; | |
481 | ||
482 | if (!ss_initialized) { | |
483 | /* Defer initialization until selinux_complete_init, | |
484 | after the initial policy is loaded and the security | |
485 | server is ready to handle calls. */ | |
486 | spin_lock(&sb_security_lock); | |
487 | if (list_empty(&sbsec->list)) | |
488 | list_add(&sbsec->list, &superblock_security_head); | |
489 | spin_unlock(&sb_security_lock); | |
490 | goto out; | |
491 | } | |
492 | ||
493 | /* Determine the labeling behavior to use for this filesystem type. */ | |
494 | rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid); | |
495 | if (rc) { | |
496 | printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", | |
497 | __FUNCTION__, sb->s_type->name, rc); | |
498 | goto out; | |
499 | } | |
500 | ||
501 | rc = try_context_mount(sb, data); | |
502 | if (rc) | |
503 | goto out; | |
504 | ||
505 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { | |
506 | /* Make sure that the xattr handler exists and that no | |
507 | error other than -ENODATA is returned by getxattr on | |
508 | the root directory. -ENODATA is ok, as this may be | |
509 | the first boot of the SELinux kernel before we have | |
510 | assigned xattr values to the filesystem. */ | |
511 | if (!inode->i_op->getxattr) { | |
512 | printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " | |
513 | "xattr support\n", sb->s_id, sb->s_type->name); | |
514 | rc = -EOPNOTSUPP; | |
515 | goto out; | |
516 | } | |
517 | rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); | |
518 | if (rc < 0 && rc != -ENODATA) { | |
519 | if (rc == -EOPNOTSUPP) | |
520 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
521 | "%s) has no security xattr handler\n", | |
522 | sb->s_id, sb->s_type->name); | |
523 | else | |
524 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
525 | "%s) getxattr errno %d\n", sb->s_id, | |
526 | sb->s_type->name, -rc); | |
527 | goto out; | |
528 | } | |
529 | } | |
530 | ||
531 | if (strcmp(sb->s_type->name, "proc") == 0) | |
532 | sbsec->proc = 1; | |
533 | ||
534 | sbsec->initialized = 1; | |
535 | ||
536 | if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) { | |
537 | printk(KERN_INFO "SELinux: initialized (dev %s, type %s), unknown behavior\n", | |
538 | sb->s_id, sb->s_type->name); | |
539 | } | |
540 | else { | |
541 | printk(KERN_INFO "SELinux: initialized (dev %s, type %s), %s\n", | |
542 | sb->s_id, sb->s_type->name, | |
543 | labeling_behaviors[sbsec->behavior-1]); | |
544 | } | |
545 | ||
546 | /* Initialize the root inode. */ | |
547 | rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root); | |
548 | ||
549 | /* Initialize any other inodes associated with the superblock, e.g. | |
550 | inodes created prior to initial policy load or inodes created | |
551 | during get_sb by a pseudo filesystem that directly | |
552 | populates itself. */ | |
553 | spin_lock(&sbsec->isec_lock); | |
554 | next_inode: | |
555 | if (!list_empty(&sbsec->isec_head)) { | |
556 | struct inode_security_struct *isec = | |
557 | list_entry(sbsec->isec_head.next, | |
558 | struct inode_security_struct, list); | |
559 | struct inode *inode = isec->inode; | |
560 | spin_unlock(&sbsec->isec_lock); | |
561 | inode = igrab(inode); | |
562 | if (inode) { | |
563 | if (!IS_PRIVATE (inode)) | |
564 | inode_doinit(inode); | |
565 | iput(inode); | |
566 | } | |
567 | spin_lock(&sbsec->isec_lock); | |
568 | list_del_init(&isec->list); | |
569 | goto next_inode; | |
570 | } | |
571 | spin_unlock(&sbsec->isec_lock); | |
572 | out: | |
573 | up(&sbsec->sem); | |
574 | return rc; | |
575 | } | |
576 | ||
577 | static inline u16 inode_mode_to_security_class(umode_t mode) | |
578 | { | |
579 | switch (mode & S_IFMT) { | |
580 | case S_IFSOCK: | |
581 | return SECCLASS_SOCK_FILE; | |
582 | case S_IFLNK: | |
583 | return SECCLASS_LNK_FILE; | |
584 | case S_IFREG: | |
585 | return SECCLASS_FILE; | |
586 | case S_IFBLK: | |
587 | return SECCLASS_BLK_FILE; | |
588 | case S_IFDIR: | |
589 | return SECCLASS_DIR; | |
590 | case S_IFCHR: | |
591 | return SECCLASS_CHR_FILE; | |
592 | case S_IFIFO: | |
593 | return SECCLASS_FIFO_FILE; | |
594 | ||
595 | } | |
596 | ||
597 | return SECCLASS_FILE; | |
598 | } | |
599 | ||
13402580 JM |
600 | static inline int default_protocol_stream(int protocol) |
601 | { | |
602 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
603 | } | |
604 | ||
605 | static inline int default_protocol_dgram(int protocol) | |
606 | { | |
607 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
608 | } | |
609 | ||
1da177e4 LT |
610 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
611 | { | |
612 | switch (family) { | |
613 | case PF_UNIX: | |
614 | switch (type) { | |
615 | case SOCK_STREAM: | |
616 | case SOCK_SEQPACKET: | |
617 | return SECCLASS_UNIX_STREAM_SOCKET; | |
618 | case SOCK_DGRAM: | |
619 | return SECCLASS_UNIX_DGRAM_SOCKET; | |
620 | } | |
621 | break; | |
622 | case PF_INET: | |
623 | case PF_INET6: | |
624 | switch (type) { | |
625 | case SOCK_STREAM: | |
13402580 JM |
626 | if (default_protocol_stream(protocol)) |
627 | return SECCLASS_TCP_SOCKET; | |
628 | else | |
629 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 630 | case SOCK_DGRAM: |
13402580 JM |
631 | if (default_protocol_dgram(protocol)) |
632 | return SECCLASS_UDP_SOCKET; | |
633 | else | |
634 | return SECCLASS_RAWIP_SOCKET; | |
635 | default: | |
1da177e4 LT |
636 | return SECCLASS_RAWIP_SOCKET; |
637 | } | |
638 | break; | |
639 | case PF_NETLINK: | |
640 | switch (protocol) { | |
641 | case NETLINK_ROUTE: | |
642 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
643 | case NETLINK_FIREWALL: | |
644 | return SECCLASS_NETLINK_FIREWALL_SOCKET; | |
216efaaa | 645 | case NETLINK_INET_DIAG: |
1da177e4 LT |
646 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
647 | case NETLINK_NFLOG: | |
648 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
649 | case NETLINK_XFRM: | |
650 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
651 | case NETLINK_SELINUX: | |
652 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
653 | case NETLINK_AUDIT: | |
654 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
655 | case NETLINK_IP6_FW: | |
656 | return SECCLASS_NETLINK_IP6FW_SOCKET; | |
657 | case NETLINK_DNRTMSG: | |
658 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
659 | case NETLINK_KOBJECT_UEVENT: |
660 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
1da177e4 LT |
661 | default: |
662 | return SECCLASS_NETLINK_SOCKET; | |
663 | } | |
664 | case PF_PACKET: | |
665 | return SECCLASS_PACKET_SOCKET; | |
666 | case PF_KEY: | |
667 | return SECCLASS_KEY_SOCKET; | |
668 | } | |
669 | ||
670 | return SECCLASS_SOCKET; | |
671 | } | |
672 | ||
673 | #ifdef CONFIG_PROC_FS | |
674 | static int selinux_proc_get_sid(struct proc_dir_entry *de, | |
675 | u16 tclass, | |
676 | u32 *sid) | |
677 | { | |
678 | int buflen, rc; | |
679 | char *buffer, *path, *end; | |
680 | ||
681 | buffer = (char*)__get_free_page(GFP_KERNEL); | |
682 | if (!buffer) | |
683 | return -ENOMEM; | |
684 | ||
685 | buflen = PAGE_SIZE; | |
686 | end = buffer+buflen; | |
687 | *--end = '\0'; | |
688 | buflen--; | |
689 | path = end-1; | |
690 | *path = '/'; | |
691 | while (de && de != de->parent) { | |
692 | buflen -= de->namelen + 1; | |
693 | if (buflen < 0) | |
694 | break; | |
695 | end -= de->namelen; | |
696 | memcpy(end, de->name, de->namelen); | |
697 | *--end = '/'; | |
698 | path = end; | |
699 | de = de->parent; | |
700 | } | |
701 | rc = security_genfs_sid("proc", path, tclass, sid); | |
702 | free_page((unsigned long)buffer); | |
703 | return rc; | |
704 | } | |
705 | #else | |
706 | static int selinux_proc_get_sid(struct proc_dir_entry *de, | |
707 | u16 tclass, | |
708 | u32 *sid) | |
709 | { | |
710 | return -EINVAL; | |
711 | } | |
712 | #endif | |
713 | ||
714 | /* The inode's security attributes must be initialized before first use. */ | |
715 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
716 | { | |
717 | struct superblock_security_struct *sbsec = NULL; | |
718 | struct inode_security_struct *isec = inode->i_security; | |
719 | u32 sid; | |
720 | struct dentry *dentry; | |
721 | #define INITCONTEXTLEN 255 | |
722 | char *context = NULL; | |
723 | unsigned len = 0; | |
724 | int rc = 0; | |
725 | int hold_sem = 0; | |
726 | ||
727 | if (isec->initialized) | |
728 | goto out; | |
729 | ||
730 | down(&isec->sem); | |
731 | hold_sem = 1; | |
732 | if (isec->initialized) | |
733 | goto out; | |
734 | ||
735 | sbsec = inode->i_sb->s_security; | |
736 | if (!sbsec->initialized) { | |
737 | /* Defer initialization until selinux_complete_init, | |
738 | after the initial policy is loaded and the security | |
739 | server is ready to handle calls. */ | |
740 | spin_lock(&sbsec->isec_lock); | |
741 | if (list_empty(&isec->list)) | |
742 | list_add(&isec->list, &sbsec->isec_head); | |
743 | spin_unlock(&sbsec->isec_lock); | |
744 | goto out; | |
745 | } | |
746 | ||
747 | switch (sbsec->behavior) { | |
748 | case SECURITY_FS_USE_XATTR: | |
749 | if (!inode->i_op->getxattr) { | |
750 | isec->sid = sbsec->def_sid; | |
751 | break; | |
752 | } | |
753 | ||
754 | /* Need a dentry, since the xattr API requires one. | |
755 | Life would be simpler if we could just pass the inode. */ | |
756 | if (opt_dentry) { | |
757 | /* Called from d_instantiate or d_splice_alias. */ | |
758 | dentry = dget(opt_dentry); | |
759 | } else { | |
760 | /* Called from selinux_complete_init, try to find a dentry. */ | |
761 | dentry = d_find_alias(inode); | |
762 | } | |
763 | if (!dentry) { | |
764 | printk(KERN_WARNING "%s: no dentry for dev=%s " | |
765 | "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id, | |
766 | inode->i_ino); | |
767 | goto out; | |
768 | } | |
769 | ||
770 | len = INITCONTEXTLEN; | |
771 | context = kmalloc(len, GFP_KERNEL); | |
772 | if (!context) { | |
773 | rc = -ENOMEM; | |
774 | dput(dentry); | |
775 | goto out; | |
776 | } | |
777 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, | |
778 | context, len); | |
779 | if (rc == -ERANGE) { | |
780 | /* Need a larger buffer. Query for the right size. */ | |
781 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, | |
782 | NULL, 0); | |
783 | if (rc < 0) { | |
784 | dput(dentry); | |
785 | goto out; | |
786 | } | |
787 | kfree(context); | |
788 | len = rc; | |
789 | context = kmalloc(len, GFP_KERNEL); | |
790 | if (!context) { | |
791 | rc = -ENOMEM; | |
792 | dput(dentry); | |
793 | goto out; | |
794 | } | |
795 | rc = inode->i_op->getxattr(dentry, | |
796 | XATTR_NAME_SELINUX, | |
797 | context, len); | |
798 | } | |
799 | dput(dentry); | |
800 | if (rc < 0) { | |
801 | if (rc != -ENODATA) { | |
802 | printk(KERN_WARNING "%s: getxattr returned " | |
803 | "%d for dev=%s ino=%ld\n", __FUNCTION__, | |
804 | -rc, inode->i_sb->s_id, inode->i_ino); | |
805 | kfree(context); | |
806 | goto out; | |
807 | } | |
808 | /* Map ENODATA to the default file SID */ | |
809 | sid = sbsec->def_sid; | |
810 | rc = 0; | |
811 | } else { | |
f5c1d5b2 JM |
812 | rc = security_context_to_sid_default(context, rc, &sid, |
813 | sbsec->def_sid); | |
1da177e4 LT |
814 | if (rc) { |
815 | printk(KERN_WARNING "%s: context_to_sid(%s) " | |
816 | "returned %d for dev=%s ino=%ld\n", | |
817 | __FUNCTION__, context, -rc, | |
818 | inode->i_sb->s_id, inode->i_ino); | |
819 | kfree(context); | |
820 | /* Leave with the unlabeled SID */ | |
821 | rc = 0; | |
822 | break; | |
823 | } | |
824 | } | |
825 | kfree(context); | |
826 | isec->sid = sid; | |
827 | break; | |
828 | case SECURITY_FS_USE_TASK: | |
829 | isec->sid = isec->task_sid; | |
830 | break; | |
831 | case SECURITY_FS_USE_TRANS: | |
832 | /* Default to the fs SID. */ | |
833 | isec->sid = sbsec->sid; | |
834 | ||
835 | /* Try to obtain a transition SID. */ | |
836 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
837 | rc = security_transition_sid(isec->task_sid, | |
838 | sbsec->sid, | |
839 | isec->sclass, | |
840 | &sid); | |
841 | if (rc) | |
842 | goto out; | |
843 | isec->sid = sid; | |
844 | break; | |
845 | default: | |
846 | /* Default to the fs SID. */ | |
847 | isec->sid = sbsec->sid; | |
848 | ||
849 | if (sbsec->proc) { | |
850 | struct proc_inode *proci = PROC_I(inode); | |
851 | if (proci->pde) { | |
852 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
853 | rc = selinux_proc_get_sid(proci->pde, | |
854 | isec->sclass, | |
855 | &sid); | |
856 | if (rc) | |
857 | goto out; | |
858 | isec->sid = sid; | |
859 | } | |
860 | } | |
861 | break; | |
862 | } | |
863 | ||
864 | isec->initialized = 1; | |
865 | ||
866 | out: | |
867 | if (isec->sclass == SECCLASS_FILE) | |
868 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
869 | ||
870 | if (hold_sem) | |
871 | up(&isec->sem); | |
872 | return rc; | |
873 | } | |
874 | ||
875 | /* Convert a Linux signal to an access vector. */ | |
876 | static inline u32 signal_to_av(int sig) | |
877 | { | |
878 | u32 perm = 0; | |
879 | ||
880 | switch (sig) { | |
881 | case SIGCHLD: | |
882 | /* Commonly granted from child to parent. */ | |
883 | perm = PROCESS__SIGCHLD; | |
884 | break; | |
885 | case SIGKILL: | |
886 | /* Cannot be caught or ignored */ | |
887 | perm = PROCESS__SIGKILL; | |
888 | break; | |
889 | case SIGSTOP: | |
890 | /* Cannot be caught or ignored */ | |
891 | perm = PROCESS__SIGSTOP; | |
892 | break; | |
893 | default: | |
894 | /* All other signals. */ | |
895 | perm = PROCESS__SIGNAL; | |
896 | break; | |
897 | } | |
898 | ||
899 | return perm; | |
900 | } | |
901 | ||
902 | /* Check permission betweeen a pair of tasks, e.g. signal checks, | |
903 | fork check, ptrace check, etc. */ | |
904 | static int task_has_perm(struct task_struct *tsk1, | |
905 | struct task_struct *tsk2, | |
906 | u32 perms) | |
907 | { | |
908 | struct task_security_struct *tsec1, *tsec2; | |
909 | ||
910 | tsec1 = tsk1->security; | |
911 | tsec2 = tsk2->security; | |
912 | return avc_has_perm(tsec1->sid, tsec2->sid, | |
913 | SECCLASS_PROCESS, perms, NULL); | |
914 | } | |
915 | ||
916 | /* Check whether a task is allowed to use a capability. */ | |
917 | static int task_has_capability(struct task_struct *tsk, | |
918 | int cap) | |
919 | { | |
920 | struct task_security_struct *tsec; | |
921 | struct avc_audit_data ad; | |
922 | ||
923 | tsec = tsk->security; | |
924 | ||
925 | AVC_AUDIT_DATA_INIT(&ad,CAP); | |
926 | ad.tsk = tsk; | |
927 | ad.u.cap = cap; | |
928 | ||
929 | return avc_has_perm(tsec->sid, tsec->sid, | |
930 | SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad); | |
931 | } | |
932 | ||
933 | /* Check whether a task is allowed to use a system operation. */ | |
934 | static int task_has_system(struct task_struct *tsk, | |
935 | u32 perms) | |
936 | { | |
937 | struct task_security_struct *tsec; | |
938 | ||
939 | tsec = tsk->security; | |
940 | ||
941 | return avc_has_perm(tsec->sid, SECINITSID_KERNEL, | |
942 | SECCLASS_SYSTEM, perms, NULL); | |
943 | } | |
944 | ||
945 | /* Check whether a task has a particular permission to an inode. | |
946 | The 'adp' parameter is optional and allows other audit | |
947 | data to be passed (e.g. the dentry). */ | |
948 | static int inode_has_perm(struct task_struct *tsk, | |
949 | struct inode *inode, | |
950 | u32 perms, | |
951 | struct avc_audit_data *adp) | |
952 | { | |
953 | struct task_security_struct *tsec; | |
954 | struct inode_security_struct *isec; | |
955 | struct avc_audit_data ad; | |
956 | ||
957 | tsec = tsk->security; | |
958 | isec = inode->i_security; | |
959 | ||
960 | if (!adp) { | |
961 | adp = &ad; | |
962 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
963 | ad.u.fs.inode = inode; | |
964 | } | |
965 | ||
966 | return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp); | |
967 | } | |
968 | ||
969 | /* Same as inode_has_perm, but pass explicit audit data containing | |
970 | the dentry to help the auditing code to more easily generate the | |
971 | pathname if needed. */ | |
972 | static inline int dentry_has_perm(struct task_struct *tsk, | |
973 | struct vfsmount *mnt, | |
974 | struct dentry *dentry, | |
975 | u32 av) | |
976 | { | |
977 | struct inode *inode = dentry->d_inode; | |
978 | struct avc_audit_data ad; | |
979 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
980 | ad.u.fs.mnt = mnt; | |
981 | ad.u.fs.dentry = dentry; | |
982 | return inode_has_perm(tsk, inode, av, &ad); | |
983 | } | |
984 | ||
985 | /* Check whether a task can use an open file descriptor to | |
986 | access an inode in a given way. Check access to the | |
987 | descriptor itself, and then use dentry_has_perm to | |
988 | check a particular permission to the file. | |
989 | Access to the descriptor is implicitly granted if it | |
990 | has the same SID as the process. If av is zero, then | |
991 | access to the file is not checked, e.g. for cases | |
992 | where only the descriptor is affected like seek. */ | |
858119e1 | 993 | static int file_has_perm(struct task_struct *tsk, |
1da177e4 LT |
994 | struct file *file, |
995 | u32 av) | |
996 | { | |
997 | struct task_security_struct *tsec = tsk->security; | |
998 | struct file_security_struct *fsec = file->f_security; | |
999 | struct vfsmount *mnt = file->f_vfsmnt; | |
1000 | struct dentry *dentry = file->f_dentry; | |
1001 | struct inode *inode = dentry->d_inode; | |
1002 | struct avc_audit_data ad; | |
1003 | int rc; | |
1004 | ||
1005 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1006 | ad.u.fs.mnt = mnt; | |
1007 | ad.u.fs.dentry = dentry; | |
1008 | ||
1009 | if (tsec->sid != fsec->sid) { | |
1010 | rc = avc_has_perm(tsec->sid, fsec->sid, | |
1011 | SECCLASS_FD, | |
1012 | FD__USE, | |
1013 | &ad); | |
1014 | if (rc) | |
1015 | return rc; | |
1016 | } | |
1017 | ||
1018 | /* av is zero if only checking access to the descriptor. */ | |
1019 | if (av) | |
1020 | return inode_has_perm(tsk, inode, av, &ad); | |
1021 | ||
1022 | return 0; | |
1023 | } | |
1024 | ||
1025 | /* Check whether a task can create a file. */ | |
1026 | static int may_create(struct inode *dir, | |
1027 | struct dentry *dentry, | |
1028 | u16 tclass) | |
1029 | { | |
1030 | struct task_security_struct *tsec; | |
1031 | struct inode_security_struct *dsec; | |
1032 | struct superblock_security_struct *sbsec; | |
1033 | u32 newsid; | |
1034 | struct avc_audit_data ad; | |
1035 | int rc; | |
1036 | ||
1037 | tsec = current->security; | |
1038 | dsec = dir->i_security; | |
1039 | sbsec = dir->i_sb->s_security; | |
1040 | ||
1041 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1042 | ad.u.fs.dentry = dentry; | |
1043 | ||
1044 | rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, | |
1045 | DIR__ADD_NAME | DIR__SEARCH, | |
1046 | &ad); | |
1047 | if (rc) | |
1048 | return rc; | |
1049 | ||
1050 | if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { | |
1051 | newsid = tsec->create_sid; | |
1052 | } else { | |
1053 | rc = security_transition_sid(tsec->sid, dsec->sid, tclass, | |
1054 | &newsid); | |
1055 | if (rc) | |
1056 | return rc; | |
1057 | } | |
1058 | ||
1059 | rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad); | |
1060 | if (rc) | |
1061 | return rc; | |
1062 | ||
1063 | return avc_has_perm(newsid, sbsec->sid, | |
1064 | SECCLASS_FILESYSTEM, | |
1065 | FILESYSTEM__ASSOCIATE, &ad); | |
1066 | } | |
1067 | ||
1068 | #define MAY_LINK 0 | |
1069 | #define MAY_UNLINK 1 | |
1070 | #define MAY_RMDIR 2 | |
1071 | ||
1072 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1073 | static int may_link(struct inode *dir, | |
1074 | struct dentry *dentry, | |
1075 | int kind) | |
1076 | ||
1077 | { | |
1078 | struct task_security_struct *tsec; | |
1079 | struct inode_security_struct *dsec, *isec; | |
1080 | struct avc_audit_data ad; | |
1081 | u32 av; | |
1082 | int rc; | |
1083 | ||
1084 | tsec = current->security; | |
1085 | dsec = dir->i_security; | |
1086 | isec = dentry->d_inode->i_security; | |
1087 | ||
1088 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1089 | ad.u.fs.dentry = dentry; | |
1090 | ||
1091 | av = DIR__SEARCH; | |
1092 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
1093 | rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad); | |
1094 | if (rc) | |
1095 | return rc; | |
1096 | ||
1097 | switch (kind) { | |
1098 | case MAY_LINK: | |
1099 | av = FILE__LINK; | |
1100 | break; | |
1101 | case MAY_UNLINK: | |
1102 | av = FILE__UNLINK; | |
1103 | break; | |
1104 | case MAY_RMDIR: | |
1105 | av = DIR__RMDIR; | |
1106 | break; | |
1107 | default: | |
1108 | printk(KERN_WARNING "may_link: unrecognized kind %d\n", kind); | |
1109 | return 0; | |
1110 | } | |
1111 | ||
1112 | rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad); | |
1113 | return rc; | |
1114 | } | |
1115 | ||
1116 | static inline int may_rename(struct inode *old_dir, | |
1117 | struct dentry *old_dentry, | |
1118 | struct inode *new_dir, | |
1119 | struct dentry *new_dentry) | |
1120 | { | |
1121 | struct task_security_struct *tsec; | |
1122 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; | |
1123 | struct avc_audit_data ad; | |
1124 | u32 av; | |
1125 | int old_is_dir, new_is_dir; | |
1126 | int rc; | |
1127 | ||
1128 | tsec = current->security; | |
1129 | old_dsec = old_dir->i_security; | |
1130 | old_isec = old_dentry->d_inode->i_security; | |
1131 | old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); | |
1132 | new_dsec = new_dir->i_security; | |
1133 | ||
1134 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1135 | ||
1136 | ad.u.fs.dentry = old_dentry; | |
1137 | rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR, | |
1138 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); | |
1139 | if (rc) | |
1140 | return rc; | |
1141 | rc = avc_has_perm(tsec->sid, old_isec->sid, | |
1142 | old_isec->sclass, FILE__RENAME, &ad); | |
1143 | if (rc) | |
1144 | return rc; | |
1145 | if (old_is_dir && new_dir != old_dir) { | |
1146 | rc = avc_has_perm(tsec->sid, old_isec->sid, | |
1147 | old_isec->sclass, DIR__REPARENT, &ad); | |
1148 | if (rc) | |
1149 | return rc; | |
1150 | } | |
1151 | ||
1152 | ad.u.fs.dentry = new_dentry; | |
1153 | av = DIR__ADD_NAME | DIR__SEARCH; | |
1154 | if (new_dentry->d_inode) | |
1155 | av |= DIR__REMOVE_NAME; | |
1156 | rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad); | |
1157 | if (rc) | |
1158 | return rc; | |
1159 | if (new_dentry->d_inode) { | |
1160 | new_isec = new_dentry->d_inode->i_security; | |
1161 | new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); | |
1162 | rc = avc_has_perm(tsec->sid, new_isec->sid, | |
1163 | new_isec->sclass, | |
1164 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1165 | if (rc) | |
1166 | return rc; | |
1167 | } | |
1168 | ||
1169 | return 0; | |
1170 | } | |
1171 | ||
1172 | /* Check whether a task can perform a filesystem operation. */ | |
1173 | static int superblock_has_perm(struct task_struct *tsk, | |
1174 | struct super_block *sb, | |
1175 | u32 perms, | |
1176 | struct avc_audit_data *ad) | |
1177 | { | |
1178 | struct task_security_struct *tsec; | |
1179 | struct superblock_security_struct *sbsec; | |
1180 | ||
1181 | tsec = tsk->security; | |
1182 | sbsec = sb->s_security; | |
1183 | return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
1184 | perms, ad); | |
1185 | } | |
1186 | ||
1187 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1188 | static inline u32 file_mask_to_av(int mode, int mask) | |
1189 | { | |
1190 | u32 av = 0; | |
1191 | ||
1192 | if ((mode & S_IFMT) != S_IFDIR) { | |
1193 | if (mask & MAY_EXEC) | |
1194 | av |= FILE__EXECUTE; | |
1195 | if (mask & MAY_READ) | |
1196 | av |= FILE__READ; | |
1197 | ||
1198 | if (mask & MAY_APPEND) | |
1199 | av |= FILE__APPEND; | |
1200 | else if (mask & MAY_WRITE) | |
1201 | av |= FILE__WRITE; | |
1202 | ||
1203 | } else { | |
1204 | if (mask & MAY_EXEC) | |
1205 | av |= DIR__SEARCH; | |
1206 | if (mask & MAY_WRITE) | |
1207 | av |= DIR__WRITE; | |
1208 | if (mask & MAY_READ) | |
1209 | av |= DIR__READ; | |
1210 | } | |
1211 | ||
1212 | return av; | |
1213 | } | |
1214 | ||
1215 | /* Convert a Linux file to an access vector. */ | |
1216 | static inline u32 file_to_av(struct file *file) | |
1217 | { | |
1218 | u32 av = 0; | |
1219 | ||
1220 | if (file->f_mode & FMODE_READ) | |
1221 | av |= FILE__READ; | |
1222 | if (file->f_mode & FMODE_WRITE) { | |
1223 | if (file->f_flags & O_APPEND) | |
1224 | av |= FILE__APPEND; | |
1225 | else | |
1226 | av |= FILE__WRITE; | |
1227 | } | |
1228 | ||
1229 | return av; | |
1230 | } | |
1231 | ||
1232 | /* Set an inode's SID to a specified value. */ | |
1233 | static int inode_security_set_sid(struct inode *inode, u32 sid) | |
1234 | { | |
1235 | struct inode_security_struct *isec = inode->i_security; | |
1236 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
1237 | ||
1238 | if (!sbsec->initialized) { | |
1239 | /* Defer initialization to selinux_complete_init. */ | |
1240 | return 0; | |
1241 | } | |
1242 | ||
1243 | down(&isec->sem); | |
1244 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1245 | isec->sid = sid; | |
1246 | isec->initialized = 1; | |
1247 | up(&isec->sem); | |
1248 | return 0; | |
1249 | } | |
1250 | ||
1da177e4 LT |
1251 | /* Hook functions begin here. */ |
1252 | ||
1253 | static int selinux_ptrace(struct task_struct *parent, struct task_struct *child) | |
1254 | { | |
1255 | struct task_security_struct *psec = parent->security; | |
1256 | struct task_security_struct *csec = child->security; | |
1257 | int rc; | |
1258 | ||
1259 | rc = secondary_ops->ptrace(parent,child); | |
1260 | if (rc) | |
1261 | return rc; | |
1262 | ||
1263 | rc = task_has_perm(parent, child, PROCESS__PTRACE); | |
1264 | /* Save the SID of the tracing process for later use in apply_creds. */ | |
1265 | if (!rc) | |
1266 | csec->ptrace_sid = psec->sid; | |
1267 | return rc; | |
1268 | } | |
1269 | ||
1270 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
1271 | kernel_cap_t *inheritable, kernel_cap_t *permitted) | |
1272 | { | |
1273 | int error; | |
1274 | ||
1275 | error = task_has_perm(current, target, PROCESS__GETCAP); | |
1276 | if (error) | |
1277 | return error; | |
1278 | ||
1279 | return secondary_ops->capget(target, effective, inheritable, permitted); | |
1280 | } | |
1281 | ||
1282 | static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective, | |
1283 | kernel_cap_t *inheritable, kernel_cap_t *permitted) | |
1284 | { | |
1285 | int error; | |
1286 | ||
1287 | error = secondary_ops->capset_check(target, effective, inheritable, permitted); | |
1288 | if (error) | |
1289 | return error; | |
1290 | ||
1291 | return task_has_perm(current, target, PROCESS__SETCAP); | |
1292 | } | |
1293 | ||
1294 | static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective, | |
1295 | kernel_cap_t *inheritable, kernel_cap_t *permitted) | |
1296 | { | |
1297 | secondary_ops->capset_set(target, effective, inheritable, permitted); | |
1298 | } | |
1299 | ||
1300 | static int selinux_capable(struct task_struct *tsk, int cap) | |
1301 | { | |
1302 | int rc; | |
1303 | ||
1304 | rc = secondary_ops->capable(tsk, cap); | |
1305 | if (rc) | |
1306 | return rc; | |
1307 | ||
1308 | return task_has_capability(tsk,cap); | |
1309 | } | |
1310 | ||
1311 | static int selinux_sysctl(ctl_table *table, int op) | |
1312 | { | |
1313 | int error = 0; | |
1314 | u32 av; | |
1315 | struct task_security_struct *tsec; | |
1316 | u32 tsid; | |
1317 | int rc; | |
1318 | ||
1319 | rc = secondary_ops->sysctl(table, op); | |
1320 | if (rc) | |
1321 | return rc; | |
1322 | ||
1323 | tsec = current->security; | |
1324 | ||
1325 | rc = selinux_proc_get_sid(table->de, (op == 001) ? | |
1326 | SECCLASS_DIR : SECCLASS_FILE, &tsid); | |
1327 | if (rc) { | |
1328 | /* Default to the well-defined sysctl SID. */ | |
1329 | tsid = SECINITSID_SYSCTL; | |
1330 | } | |
1331 | ||
1332 | /* The op values are "defined" in sysctl.c, thereby creating | |
1333 | * a bad coupling between this module and sysctl.c */ | |
1334 | if(op == 001) { | |
1335 | error = avc_has_perm(tsec->sid, tsid, | |
1336 | SECCLASS_DIR, DIR__SEARCH, NULL); | |
1337 | } else { | |
1338 | av = 0; | |
1339 | if (op & 004) | |
1340 | av |= FILE__READ; | |
1341 | if (op & 002) | |
1342 | av |= FILE__WRITE; | |
1343 | if (av) | |
1344 | error = avc_has_perm(tsec->sid, tsid, | |
1345 | SECCLASS_FILE, av, NULL); | |
1346 | } | |
1347 | ||
1348 | return error; | |
1349 | } | |
1350 | ||
1351 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) | |
1352 | { | |
1353 | int rc = 0; | |
1354 | ||
1355 | if (!sb) | |
1356 | return 0; | |
1357 | ||
1358 | switch (cmds) { | |
1359 | case Q_SYNC: | |
1360 | case Q_QUOTAON: | |
1361 | case Q_QUOTAOFF: | |
1362 | case Q_SETINFO: | |
1363 | case Q_SETQUOTA: | |
1364 | rc = superblock_has_perm(current, | |
1365 | sb, | |
1366 | FILESYSTEM__QUOTAMOD, NULL); | |
1367 | break; | |
1368 | case Q_GETFMT: | |
1369 | case Q_GETINFO: | |
1370 | case Q_GETQUOTA: | |
1371 | rc = superblock_has_perm(current, | |
1372 | sb, | |
1373 | FILESYSTEM__QUOTAGET, NULL); | |
1374 | break; | |
1375 | default: | |
1376 | rc = 0; /* let the kernel handle invalid cmds */ | |
1377 | break; | |
1378 | } | |
1379 | return rc; | |
1380 | } | |
1381 | ||
1382 | static int selinux_quota_on(struct dentry *dentry) | |
1383 | { | |
1384 | return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON); | |
1385 | } | |
1386 | ||
1387 | static int selinux_syslog(int type) | |
1388 | { | |
1389 | int rc; | |
1390 | ||
1391 | rc = secondary_ops->syslog(type); | |
1392 | if (rc) | |
1393 | return rc; | |
1394 | ||
1395 | switch (type) { | |
1396 | case 3: /* Read last kernel messages */ | |
1397 | case 10: /* Return size of the log buffer */ | |
1398 | rc = task_has_system(current, SYSTEM__SYSLOG_READ); | |
1399 | break; | |
1400 | case 6: /* Disable logging to console */ | |
1401 | case 7: /* Enable logging to console */ | |
1402 | case 8: /* Set level of messages printed to console */ | |
1403 | rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); | |
1404 | break; | |
1405 | case 0: /* Close log */ | |
1406 | case 1: /* Open log */ | |
1407 | case 2: /* Read from log */ | |
1408 | case 4: /* Read/clear last kernel messages */ | |
1409 | case 5: /* Clear ring buffer */ | |
1410 | default: | |
1411 | rc = task_has_system(current, SYSTEM__SYSLOG_MOD); | |
1412 | break; | |
1413 | } | |
1414 | return rc; | |
1415 | } | |
1416 | ||
1417 | /* | |
1418 | * Check that a process has enough memory to allocate a new virtual | |
1419 | * mapping. 0 means there is enough memory for the allocation to | |
1420 | * succeed and -ENOMEM implies there is not. | |
1421 | * | |
1422 | * Note that secondary_ops->capable and task_has_perm_noaudit return 0 | |
1423 | * if the capability is granted, but __vm_enough_memory requires 1 if | |
1424 | * the capability is granted. | |
1425 | * | |
1426 | * Do not audit the selinux permission check, as this is applied to all | |
1427 | * processes that allocate mappings. | |
1428 | */ | |
1429 | static int selinux_vm_enough_memory(long pages) | |
1430 | { | |
1431 | int rc, cap_sys_admin = 0; | |
1432 | struct task_security_struct *tsec = current->security; | |
1433 | ||
1434 | rc = secondary_ops->capable(current, CAP_SYS_ADMIN); | |
1435 | if (rc == 0) | |
1436 | rc = avc_has_perm_noaudit(tsec->sid, tsec->sid, | |
1437 | SECCLASS_CAPABILITY, | |
1438 | CAP_TO_MASK(CAP_SYS_ADMIN), | |
1439 | NULL); | |
1440 | ||
1441 | if (rc == 0) | |
1442 | cap_sys_admin = 1; | |
1443 | ||
1444 | return __vm_enough_memory(pages, cap_sys_admin); | |
1445 | } | |
1446 | ||
1447 | /* binprm security operations */ | |
1448 | ||
1449 | static int selinux_bprm_alloc_security(struct linux_binprm *bprm) | |
1450 | { | |
1451 | struct bprm_security_struct *bsec; | |
1452 | ||
89d155ef | 1453 | bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL); |
1da177e4 LT |
1454 | if (!bsec) |
1455 | return -ENOMEM; | |
1456 | ||
1da177e4 LT |
1457 | bsec->bprm = bprm; |
1458 | bsec->sid = SECINITSID_UNLABELED; | |
1459 | bsec->set = 0; | |
1460 | ||
1461 | bprm->security = bsec; | |
1462 | return 0; | |
1463 | } | |
1464 | ||
1465 | static int selinux_bprm_set_security(struct linux_binprm *bprm) | |
1466 | { | |
1467 | struct task_security_struct *tsec; | |
1468 | struct inode *inode = bprm->file->f_dentry->d_inode; | |
1469 | struct inode_security_struct *isec; | |
1470 | struct bprm_security_struct *bsec; | |
1471 | u32 newsid; | |
1472 | struct avc_audit_data ad; | |
1473 | int rc; | |
1474 | ||
1475 | rc = secondary_ops->bprm_set_security(bprm); | |
1476 | if (rc) | |
1477 | return rc; | |
1478 | ||
1479 | bsec = bprm->security; | |
1480 | ||
1481 | if (bsec->set) | |
1482 | return 0; | |
1483 | ||
1484 | tsec = current->security; | |
1485 | isec = inode->i_security; | |
1486 | ||
1487 | /* Default to the current task SID. */ | |
1488 | bsec->sid = tsec->sid; | |
1489 | ||
1490 | /* Reset create SID on execve. */ | |
1491 | tsec->create_sid = 0; | |
1492 | ||
1493 | if (tsec->exec_sid) { | |
1494 | newsid = tsec->exec_sid; | |
1495 | /* Reset exec SID on execve. */ | |
1496 | tsec->exec_sid = 0; | |
1497 | } else { | |
1498 | /* Check for a default transition on this program. */ | |
1499 | rc = security_transition_sid(tsec->sid, isec->sid, | |
1500 | SECCLASS_PROCESS, &newsid); | |
1501 | if (rc) | |
1502 | return rc; | |
1503 | } | |
1504 | ||
1505 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1506 | ad.u.fs.mnt = bprm->file->f_vfsmnt; | |
1507 | ad.u.fs.dentry = bprm->file->f_dentry; | |
1508 | ||
1509 | if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID) | |
1510 | newsid = tsec->sid; | |
1511 | ||
1512 | if (tsec->sid == newsid) { | |
1513 | rc = avc_has_perm(tsec->sid, isec->sid, | |
1514 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); | |
1515 | if (rc) | |
1516 | return rc; | |
1517 | } else { | |
1518 | /* Check permissions for the transition. */ | |
1519 | rc = avc_has_perm(tsec->sid, newsid, | |
1520 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); | |
1521 | if (rc) | |
1522 | return rc; | |
1523 | ||
1524 | rc = avc_has_perm(newsid, isec->sid, | |
1525 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); | |
1526 | if (rc) | |
1527 | return rc; | |
1528 | ||
1529 | /* Clear any possibly unsafe personality bits on exec: */ | |
1530 | current->personality &= ~PER_CLEAR_ON_SETID; | |
1531 | ||
1532 | /* Set the security field to the new SID. */ | |
1533 | bsec->sid = newsid; | |
1534 | } | |
1535 | ||
1536 | bsec->set = 1; | |
1537 | return 0; | |
1538 | } | |
1539 | ||
1540 | static int selinux_bprm_check_security (struct linux_binprm *bprm) | |
1541 | { | |
1542 | return secondary_ops->bprm_check_security(bprm); | |
1543 | } | |
1544 | ||
1545 | ||
1546 | static int selinux_bprm_secureexec (struct linux_binprm *bprm) | |
1547 | { | |
1548 | struct task_security_struct *tsec = current->security; | |
1549 | int atsecure = 0; | |
1550 | ||
1551 | if (tsec->osid != tsec->sid) { | |
1552 | /* Enable secure mode for SIDs transitions unless | |
1553 | the noatsecure permission is granted between | |
1554 | the two SIDs, i.e. ahp returns 0. */ | |
1555 | atsecure = avc_has_perm(tsec->osid, tsec->sid, | |
1556 | SECCLASS_PROCESS, | |
1557 | PROCESS__NOATSECURE, NULL); | |
1558 | } | |
1559 | ||
1560 | return (atsecure || secondary_ops->bprm_secureexec(bprm)); | |
1561 | } | |
1562 | ||
1563 | static void selinux_bprm_free_security(struct linux_binprm *bprm) | |
1564 | { | |
9a5f04bf | 1565 | kfree(bprm->security); |
1da177e4 | 1566 | bprm->security = NULL; |
1da177e4 LT |
1567 | } |
1568 | ||
1569 | extern struct vfsmount *selinuxfs_mount; | |
1570 | extern struct dentry *selinux_null; | |
1571 | ||
1572 | /* Derived from fs/exec.c:flush_old_files. */ | |
1573 | static inline void flush_unauthorized_files(struct files_struct * files) | |
1574 | { | |
1575 | struct avc_audit_data ad; | |
1576 | struct file *file, *devnull = NULL; | |
1577 | struct tty_struct *tty = current->signal->tty; | |
badf1662 | 1578 | struct fdtable *fdt; |
1da177e4 LT |
1579 | long j = -1; |
1580 | ||
1581 | if (tty) { | |
1582 | file_list_lock(); | |
2f512016 | 1583 | file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list); |
1da177e4 LT |
1584 | if (file) { |
1585 | /* Revalidate access to controlling tty. | |
1586 | Use inode_has_perm on the tty inode directly rather | |
1587 | than using file_has_perm, as this particular open | |
1588 | file may belong to another process and we are only | |
1589 | interested in the inode-based check here. */ | |
1590 | struct inode *inode = file->f_dentry->d_inode; | |
1591 | if (inode_has_perm(current, inode, | |
1592 | FILE__READ | FILE__WRITE, NULL)) { | |
1593 | /* Reset controlling tty. */ | |
1594 | current->signal->tty = NULL; | |
1595 | current->signal->tty_old_pgrp = 0; | |
1596 | } | |
1597 | } | |
1598 | file_list_unlock(); | |
1599 | } | |
1600 | ||
1601 | /* Revalidate access to inherited open files. */ | |
1602 | ||
1603 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
1604 | ||
1605 | spin_lock(&files->file_lock); | |
1606 | for (;;) { | |
1607 | unsigned long set, i; | |
1608 | int fd; | |
1609 | ||
1610 | j++; | |
1611 | i = j * __NFDBITS; | |
badf1662 DS |
1612 | fdt = files_fdtable(files); |
1613 | if (i >= fdt->max_fds || i >= fdt->max_fdset) | |
1da177e4 | 1614 | break; |
badf1662 | 1615 | set = fdt->open_fds->fds_bits[j]; |
1da177e4 LT |
1616 | if (!set) |
1617 | continue; | |
1618 | spin_unlock(&files->file_lock); | |
1619 | for ( ; set ; i++,set >>= 1) { | |
1620 | if (set & 1) { | |
1621 | file = fget(i); | |
1622 | if (!file) | |
1623 | continue; | |
1624 | if (file_has_perm(current, | |
1625 | file, | |
1626 | file_to_av(file))) { | |
1627 | sys_close(i); | |
1628 | fd = get_unused_fd(); | |
1629 | if (fd != i) { | |
1630 | if (fd >= 0) | |
1631 | put_unused_fd(fd); | |
1632 | fput(file); | |
1633 | continue; | |
1634 | } | |
1635 | if (devnull) { | |
095975da | 1636 | get_file(devnull); |
1da177e4 LT |
1637 | } else { |
1638 | devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR); | |
1639 | if (!devnull) { | |
1640 | put_unused_fd(fd); | |
1641 | fput(file); | |
1642 | continue; | |
1643 | } | |
1644 | } | |
1645 | fd_install(fd, devnull); | |
1646 | } | |
1647 | fput(file); | |
1648 | } | |
1649 | } | |
1650 | spin_lock(&files->file_lock); | |
1651 | ||
1652 | } | |
1653 | spin_unlock(&files->file_lock); | |
1654 | } | |
1655 | ||
1656 | static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe) | |
1657 | { | |
1658 | struct task_security_struct *tsec; | |
1659 | struct bprm_security_struct *bsec; | |
1660 | u32 sid; | |
1661 | int rc; | |
1662 | ||
1663 | secondary_ops->bprm_apply_creds(bprm, unsafe); | |
1664 | ||
1665 | tsec = current->security; | |
1666 | ||
1667 | bsec = bprm->security; | |
1668 | sid = bsec->sid; | |
1669 | ||
1670 | tsec->osid = tsec->sid; | |
1671 | bsec->unsafe = 0; | |
1672 | if (tsec->sid != sid) { | |
1673 | /* Check for shared state. If not ok, leave SID | |
1674 | unchanged and kill. */ | |
1675 | if (unsafe & LSM_UNSAFE_SHARE) { | |
1676 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, | |
1677 | PROCESS__SHARE, NULL); | |
1678 | if (rc) { | |
1679 | bsec->unsafe = 1; | |
1680 | return; | |
1681 | } | |
1682 | } | |
1683 | ||
1684 | /* Check for ptracing, and update the task SID if ok. | |
1685 | Otherwise, leave SID unchanged and kill. */ | |
1686 | if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { | |
1687 | rc = avc_has_perm(tsec->ptrace_sid, sid, | |
1688 | SECCLASS_PROCESS, PROCESS__PTRACE, | |
1689 | NULL); | |
1690 | if (rc) { | |
1691 | bsec->unsafe = 1; | |
1692 | return; | |
1693 | } | |
1694 | } | |
1695 | tsec->sid = sid; | |
1696 | } | |
1697 | } | |
1698 | ||
1699 | /* | |
1700 | * called after apply_creds without the task lock held | |
1701 | */ | |
1702 | static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm) | |
1703 | { | |
1704 | struct task_security_struct *tsec; | |
1705 | struct rlimit *rlim, *initrlim; | |
1706 | struct itimerval itimer; | |
1707 | struct bprm_security_struct *bsec; | |
1708 | int rc, i; | |
1709 | ||
1710 | tsec = current->security; | |
1711 | bsec = bprm->security; | |
1712 | ||
1713 | if (bsec->unsafe) { | |
1714 | force_sig_specific(SIGKILL, current); | |
1715 | return; | |
1716 | } | |
1717 | if (tsec->osid == tsec->sid) | |
1718 | return; | |
1719 | ||
1720 | /* Close files for which the new task SID is not authorized. */ | |
1721 | flush_unauthorized_files(current->files); | |
1722 | ||
1723 | /* Check whether the new SID can inherit signal state | |
1724 | from the old SID. If not, clear itimers to avoid | |
1725 | subsequent signal generation and flush and unblock | |
1726 | signals. This must occur _after_ the task SID has | |
1727 | been updated so that any kill done after the flush | |
1728 | will be checked against the new SID. */ | |
1729 | rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, | |
1730 | PROCESS__SIGINH, NULL); | |
1731 | if (rc) { | |
1732 | memset(&itimer, 0, sizeof itimer); | |
1733 | for (i = 0; i < 3; i++) | |
1734 | do_setitimer(i, &itimer, NULL); | |
1735 | flush_signals(current); | |
1736 | spin_lock_irq(¤t->sighand->siglock); | |
1737 | flush_signal_handlers(current, 1); | |
1738 | sigemptyset(¤t->blocked); | |
1739 | recalc_sigpending(); | |
1740 | spin_unlock_irq(¤t->sighand->siglock); | |
1741 | } | |
1742 | ||
1743 | /* Check whether the new SID can inherit resource limits | |
1744 | from the old SID. If not, reset all soft limits to | |
1745 | the lower of the current task's hard limit and the init | |
1746 | task's soft limit. Note that the setting of hard limits | |
1747 | (even to lower them) can be controlled by the setrlimit | |
1748 | check. The inclusion of the init task's soft limit into | |
1749 | the computation is to avoid resetting soft limits higher | |
1750 | than the default soft limit for cases where the default | |
1751 | is lower than the hard limit, e.g. RLIMIT_CORE or | |
1752 | RLIMIT_STACK.*/ | |
1753 | rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, | |
1754 | PROCESS__RLIMITINH, NULL); | |
1755 | if (rc) { | |
1756 | for (i = 0; i < RLIM_NLIMITS; i++) { | |
1757 | rlim = current->signal->rlim + i; | |
1758 | initrlim = init_task.signal->rlim+i; | |
1759 | rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur); | |
1760 | } | |
1761 | if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { | |
1762 | /* | |
1763 | * This will cause RLIMIT_CPU calculations | |
1764 | * to be refigured. | |
1765 | */ | |
1766 | current->it_prof_expires = jiffies_to_cputime(1); | |
1767 | } | |
1768 | } | |
1769 | ||
1770 | /* Wake up the parent if it is waiting so that it can | |
1771 | recheck wait permission to the new task SID. */ | |
1772 | wake_up_interruptible(¤t->parent->signal->wait_chldexit); | |
1773 | } | |
1774 | ||
1775 | /* superblock security operations */ | |
1776 | ||
1777 | static int selinux_sb_alloc_security(struct super_block *sb) | |
1778 | { | |
1779 | return superblock_alloc_security(sb); | |
1780 | } | |
1781 | ||
1782 | static void selinux_sb_free_security(struct super_block *sb) | |
1783 | { | |
1784 | superblock_free_security(sb); | |
1785 | } | |
1786 | ||
1787 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
1788 | { | |
1789 | if (plen > olen) | |
1790 | return 0; | |
1791 | ||
1792 | return !memcmp(prefix, option, plen); | |
1793 | } | |
1794 | ||
1795 | static inline int selinux_option(char *option, int len) | |
1796 | { | |
1797 | return (match_prefix("context=", sizeof("context=")-1, option, len) || | |
1798 | match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) || | |
1799 | match_prefix("defcontext=", sizeof("defcontext=")-1, option, len)); | |
1800 | } | |
1801 | ||
1802 | static inline void take_option(char **to, char *from, int *first, int len) | |
1803 | { | |
1804 | if (!*first) { | |
1805 | **to = ','; | |
1806 | *to += 1; | |
1807 | } | |
1808 | else | |
1809 | *first = 0; | |
1810 | memcpy(*to, from, len); | |
1811 | *to += len; | |
1812 | } | |
1813 | ||
1814 | static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy) | |
1815 | { | |
1816 | int fnosec, fsec, rc = 0; | |
1817 | char *in_save, *in_curr, *in_end; | |
1818 | char *sec_curr, *nosec_save, *nosec; | |
1819 | ||
1820 | in_curr = orig; | |
1821 | sec_curr = copy; | |
1822 | ||
1823 | /* Binary mount data: just copy */ | |
1824 | if (type->fs_flags & FS_BINARY_MOUNTDATA) { | |
1825 | copy_page(sec_curr, in_curr); | |
1826 | goto out; | |
1827 | } | |
1828 | ||
1829 | nosec = (char *)get_zeroed_page(GFP_KERNEL); | |
1830 | if (!nosec) { | |
1831 | rc = -ENOMEM; | |
1832 | goto out; | |
1833 | } | |
1834 | ||
1835 | nosec_save = nosec; | |
1836 | fnosec = fsec = 1; | |
1837 | in_save = in_end = orig; | |
1838 | ||
1839 | do { | |
1840 | if (*in_end == ',' || *in_end == '\0') { | |
1841 | int len = in_end - in_curr; | |
1842 | ||
1843 | if (selinux_option(in_curr, len)) | |
1844 | take_option(&sec_curr, in_curr, &fsec, len); | |
1845 | else | |
1846 | take_option(&nosec, in_curr, &fnosec, len); | |
1847 | ||
1848 | in_curr = in_end + 1; | |
1849 | } | |
1850 | } while (*in_end++); | |
1851 | ||
6931dfc9 | 1852 | strcpy(in_save, nosec_save); |
da3caa20 | 1853 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
1854 | out: |
1855 | return rc; | |
1856 | } | |
1857 | ||
1858 | static int selinux_sb_kern_mount(struct super_block *sb, void *data) | |
1859 | { | |
1860 | struct avc_audit_data ad; | |
1861 | int rc; | |
1862 | ||
1863 | rc = superblock_doinit(sb, data); | |
1864 | if (rc) | |
1865 | return rc; | |
1866 | ||
1867 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
1868 | ad.u.fs.dentry = sb->s_root; | |
1869 | return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad); | |
1870 | } | |
1871 | ||
1872 | static int selinux_sb_statfs(struct super_block *sb) | |
1873 | { | |
1874 | struct avc_audit_data ad; | |
1875 | ||
1876 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
1877 | ad.u.fs.dentry = sb->s_root; | |
1878 | return superblock_has_perm(current, sb, FILESYSTEM__GETATTR, &ad); | |
1879 | } | |
1880 | ||
1881 | static int selinux_mount(char * dev_name, | |
1882 | struct nameidata *nd, | |
1883 | char * type, | |
1884 | unsigned long flags, | |
1885 | void * data) | |
1886 | { | |
1887 | int rc; | |
1888 | ||
1889 | rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data); | |
1890 | if (rc) | |
1891 | return rc; | |
1892 | ||
1893 | if (flags & MS_REMOUNT) | |
1894 | return superblock_has_perm(current, nd->mnt->mnt_sb, | |
1895 | FILESYSTEM__REMOUNT, NULL); | |
1896 | else | |
1897 | return dentry_has_perm(current, nd->mnt, nd->dentry, | |
1898 | FILE__MOUNTON); | |
1899 | } | |
1900 | ||
1901 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
1902 | { | |
1903 | int rc; | |
1904 | ||
1905 | rc = secondary_ops->sb_umount(mnt, flags); | |
1906 | if (rc) | |
1907 | return rc; | |
1908 | ||
1909 | return superblock_has_perm(current,mnt->mnt_sb, | |
1910 | FILESYSTEM__UNMOUNT,NULL); | |
1911 | } | |
1912 | ||
1913 | /* inode security operations */ | |
1914 | ||
1915 | static int selinux_inode_alloc_security(struct inode *inode) | |
1916 | { | |
1917 | return inode_alloc_security(inode); | |
1918 | } | |
1919 | ||
1920 | static void selinux_inode_free_security(struct inode *inode) | |
1921 | { | |
1922 | inode_free_security(inode); | |
1923 | } | |
1924 | ||
5e41ff9e SS |
1925 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
1926 | char **name, void **value, | |
1927 | size_t *len) | |
1928 | { | |
1929 | struct task_security_struct *tsec; | |
1930 | struct inode_security_struct *dsec; | |
1931 | struct superblock_security_struct *sbsec; | |
1932 | struct inode_security_struct *isec; | |
570bc1c2 | 1933 | u32 newsid, clen; |
5e41ff9e | 1934 | int rc; |
570bc1c2 | 1935 | char *namep = NULL, *context; |
5e41ff9e SS |
1936 | |
1937 | tsec = current->security; | |
1938 | dsec = dir->i_security; | |
1939 | sbsec = dir->i_sb->s_security; | |
1940 | isec = inode->i_security; | |
1941 | ||
1942 | if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { | |
1943 | newsid = tsec->create_sid; | |
1944 | } else { | |
1945 | rc = security_transition_sid(tsec->sid, dsec->sid, | |
1946 | inode_mode_to_security_class(inode->i_mode), | |
1947 | &newsid); | |
1948 | if (rc) { | |
1949 | printk(KERN_WARNING "%s: " | |
1950 | "security_transition_sid failed, rc=%d (dev=%s " | |
1951 | "ino=%ld)\n", | |
1952 | __FUNCTION__, | |
1953 | -rc, inode->i_sb->s_id, inode->i_ino); | |
1954 | return rc; | |
1955 | } | |
1956 | } | |
1957 | ||
1958 | inode_security_set_sid(inode, newsid); | |
1959 | ||
25a74f3b SS |
1960 | if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) |
1961 | return -EOPNOTSUPP; | |
1962 | ||
570bc1c2 SS |
1963 | if (name) { |
1964 | namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL); | |
1965 | if (!namep) | |
1966 | return -ENOMEM; | |
1967 | *name = namep; | |
1968 | } | |
5e41ff9e | 1969 | |
570bc1c2 SS |
1970 | if (value && len) { |
1971 | rc = security_sid_to_context(newsid, &context, &clen); | |
1972 | if (rc) { | |
1973 | kfree(namep); | |
1974 | return rc; | |
1975 | } | |
1976 | *value = context; | |
1977 | *len = clen; | |
5e41ff9e | 1978 | } |
5e41ff9e | 1979 | |
5e41ff9e SS |
1980 | return 0; |
1981 | } | |
1982 | ||
1da177e4 LT |
1983 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) |
1984 | { | |
1985 | return may_create(dir, dentry, SECCLASS_FILE); | |
1986 | } | |
1987 | ||
1da177e4 LT |
1988 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
1989 | { | |
1990 | int rc; | |
1991 | ||
1992 | rc = secondary_ops->inode_link(old_dentry,dir,new_dentry); | |
1993 | if (rc) | |
1994 | return rc; | |
1995 | return may_link(dir, old_dentry, MAY_LINK); | |
1996 | } | |
1997 | ||
1da177e4 LT |
1998 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
1999 | { | |
2000 | int rc; | |
2001 | ||
2002 | rc = secondary_ops->inode_unlink(dir, dentry); | |
2003 | if (rc) | |
2004 | return rc; | |
2005 | return may_link(dir, dentry, MAY_UNLINK); | |
2006 | } | |
2007 | ||
2008 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2009 | { | |
2010 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2011 | } | |
2012 | ||
1da177e4 LT |
2013 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) |
2014 | { | |
2015 | return may_create(dir, dentry, SECCLASS_DIR); | |
2016 | } | |
2017 | ||
1da177e4 LT |
2018 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2019 | { | |
2020 | return may_link(dir, dentry, MAY_RMDIR); | |
2021 | } | |
2022 | ||
2023 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) | |
2024 | { | |
2025 | int rc; | |
2026 | ||
2027 | rc = secondary_ops->inode_mknod(dir, dentry, mode, dev); | |
2028 | if (rc) | |
2029 | return rc; | |
2030 | ||
2031 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); | |
2032 | } | |
2033 | ||
1da177e4 LT |
2034 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
2035 | struct inode *new_inode, struct dentry *new_dentry) | |
2036 | { | |
2037 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2038 | } | |
2039 | ||
1da177e4 LT |
2040 | static int selinux_inode_readlink(struct dentry *dentry) |
2041 | { | |
2042 | return dentry_has_perm(current, NULL, dentry, FILE__READ); | |
2043 | } | |
2044 | ||
2045 | static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) | |
2046 | { | |
2047 | int rc; | |
2048 | ||
2049 | rc = secondary_ops->inode_follow_link(dentry,nameidata); | |
2050 | if (rc) | |
2051 | return rc; | |
2052 | return dentry_has_perm(current, NULL, dentry, FILE__READ); | |
2053 | } | |
2054 | ||
2055 | static int selinux_inode_permission(struct inode *inode, int mask, | |
2056 | struct nameidata *nd) | |
2057 | { | |
2058 | int rc; | |
2059 | ||
2060 | rc = secondary_ops->inode_permission(inode, mask, nd); | |
2061 | if (rc) | |
2062 | return rc; | |
2063 | ||
2064 | if (!mask) { | |
2065 | /* No permission to check. Existence test. */ | |
2066 | return 0; | |
2067 | } | |
2068 | ||
2069 | return inode_has_perm(current, inode, | |
2070 | file_mask_to_av(inode->i_mode, mask), NULL); | |
2071 | } | |
2072 | ||
2073 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
2074 | { | |
2075 | int rc; | |
2076 | ||
2077 | rc = secondary_ops->inode_setattr(dentry, iattr); | |
2078 | if (rc) | |
2079 | return rc; | |
2080 | ||
2081 | if (iattr->ia_valid & ATTR_FORCE) | |
2082 | return 0; | |
2083 | ||
2084 | if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | | |
2085 | ATTR_ATIME_SET | ATTR_MTIME_SET)) | |
2086 | return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); | |
2087 | ||
2088 | return dentry_has_perm(current, NULL, dentry, FILE__WRITE); | |
2089 | } | |
2090 | ||
2091 | static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) | |
2092 | { | |
2093 | return dentry_has_perm(current, mnt, dentry, FILE__GETATTR); | |
2094 | } | |
2095 | ||
2096 | static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags) | |
2097 | { | |
2098 | struct task_security_struct *tsec = current->security; | |
2099 | struct inode *inode = dentry->d_inode; | |
2100 | struct inode_security_struct *isec = inode->i_security; | |
2101 | struct superblock_security_struct *sbsec; | |
2102 | struct avc_audit_data ad; | |
2103 | u32 newsid; | |
2104 | int rc = 0; | |
2105 | ||
2106 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
2107 | if (!strncmp(name, XATTR_SECURITY_PREFIX, | |
2108 | sizeof XATTR_SECURITY_PREFIX - 1) && | |
2109 | !capable(CAP_SYS_ADMIN)) { | |
2110 | /* A different attribute in the security namespace. | |
2111 | Restrict to administrator. */ | |
2112 | return -EPERM; | |
2113 | } | |
2114 | ||
2115 | /* Not an attribute we recognize, so just check the | |
2116 | ordinary setattr permission. */ | |
2117 | return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); | |
2118 | } | |
2119 | ||
2120 | sbsec = inode->i_sb->s_security; | |
2121 | if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) | |
2122 | return -EOPNOTSUPP; | |
2123 | ||
2124 | if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) | |
2125 | return -EPERM; | |
2126 | ||
2127 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
2128 | ad.u.fs.dentry = dentry; | |
2129 | ||
2130 | rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, | |
2131 | FILE__RELABELFROM, &ad); | |
2132 | if (rc) | |
2133 | return rc; | |
2134 | ||
2135 | rc = security_context_to_sid(value, size, &newsid); | |
2136 | if (rc) | |
2137 | return rc; | |
2138 | ||
2139 | rc = avc_has_perm(tsec->sid, newsid, isec->sclass, | |
2140 | FILE__RELABELTO, &ad); | |
2141 | if (rc) | |
2142 | return rc; | |
2143 | ||
2144 | rc = security_validate_transition(isec->sid, newsid, tsec->sid, | |
2145 | isec->sclass); | |
2146 | if (rc) | |
2147 | return rc; | |
2148 | ||
2149 | return avc_has_perm(newsid, | |
2150 | sbsec->sid, | |
2151 | SECCLASS_FILESYSTEM, | |
2152 | FILESYSTEM__ASSOCIATE, | |
2153 | &ad); | |
2154 | } | |
2155 | ||
2156 | static void selinux_inode_post_setxattr(struct dentry *dentry, char *name, | |
2157 | void *value, size_t size, int flags) | |
2158 | { | |
2159 | struct inode *inode = dentry->d_inode; | |
2160 | struct inode_security_struct *isec = inode->i_security; | |
2161 | u32 newsid; | |
2162 | int rc; | |
2163 | ||
2164 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
2165 | /* Not an attribute we recognize, so nothing to do. */ | |
2166 | return; | |
2167 | } | |
2168 | ||
2169 | rc = security_context_to_sid(value, size, &newsid); | |
2170 | if (rc) { | |
2171 | printk(KERN_WARNING "%s: unable to obtain SID for context " | |
2172 | "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc); | |
2173 | return; | |
2174 | } | |
2175 | ||
2176 | isec->sid = newsid; | |
2177 | return; | |
2178 | } | |
2179 | ||
2180 | static int selinux_inode_getxattr (struct dentry *dentry, char *name) | |
2181 | { | |
1da177e4 LT |
2182 | return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); |
2183 | } | |
2184 | ||
2185 | static int selinux_inode_listxattr (struct dentry *dentry) | |
2186 | { | |
2187 | return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); | |
2188 | } | |
2189 | ||
2190 | static int selinux_inode_removexattr (struct dentry *dentry, char *name) | |
2191 | { | |
2192 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
2193 | if (!strncmp(name, XATTR_SECURITY_PREFIX, | |
2194 | sizeof XATTR_SECURITY_PREFIX - 1) && | |
2195 | !capable(CAP_SYS_ADMIN)) { | |
2196 | /* A different attribute in the security namespace. | |
2197 | Restrict to administrator. */ | |
2198 | return -EPERM; | |
2199 | } | |
2200 | ||
2201 | /* Not an attribute we recognize, so just check the | |
2202 | ordinary setattr permission. Might want a separate | |
2203 | permission for removexattr. */ | |
2204 | return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); | |
2205 | } | |
2206 | ||
2207 | /* No one is allowed to remove a SELinux security label. | |
2208 | You can change the label, but all data must be labeled. */ | |
2209 | return -EACCES; | |
2210 | } | |
2211 | ||
d381d8a9 JM |
2212 | /* |
2213 | * Copy the in-core inode security context value to the user. If the | |
2214 | * getxattr() prior to this succeeded, check to see if we need to | |
2215 | * canonicalize the value to be finally returned to the user. | |
2216 | * | |
2217 | * Permission check is handled by selinux_inode_getxattr hook. | |
2218 | */ | |
2219 | static int selinux_inode_getsecurity(struct inode *inode, const char *name, void *buffer, size_t size, int err) | |
1da177e4 LT |
2220 | { |
2221 | struct inode_security_struct *isec = inode->i_security; | |
2222 | char *context; | |
2223 | unsigned len; | |
2224 | int rc; | |
2225 | ||
d381d8a9 JM |
2226 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) { |
2227 | rc = -EOPNOTSUPP; | |
2228 | goto out; | |
2229 | } | |
1da177e4 LT |
2230 | |
2231 | rc = security_sid_to_context(isec->sid, &context, &len); | |
2232 | if (rc) | |
d381d8a9 | 2233 | goto out; |
1da177e4 | 2234 | |
d381d8a9 | 2235 | /* Probe for required buffer size */ |
1da177e4 | 2236 | if (!buffer || !size) { |
d381d8a9 JM |
2237 | rc = len; |
2238 | goto out_free; | |
1da177e4 | 2239 | } |
d381d8a9 | 2240 | |
1da177e4 | 2241 | if (size < len) { |
d381d8a9 JM |
2242 | rc = -ERANGE; |
2243 | goto out_free; | |
2244 | } | |
2245 | ||
2246 | if (err > 0) { | |
2247 | if ((len == err) && !(memcmp(context, buffer, len))) { | |
2248 | /* Don't need to canonicalize value */ | |
2249 | rc = err; | |
2250 | goto out_free; | |
2251 | } | |
2252 | memset(buffer, 0, size); | |
1da177e4 LT |
2253 | } |
2254 | memcpy(buffer, context, len); | |
d381d8a9 JM |
2255 | rc = len; |
2256 | out_free: | |
1da177e4 | 2257 | kfree(context); |
d381d8a9 JM |
2258 | out: |
2259 | return rc; | |
1da177e4 LT |
2260 | } |
2261 | ||
2262 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
2263 | const void *value, size_t size, int flags) | |
2264 | { | |
2265 | struct inode_security_struct *isec = inode->i_security; | |
2266 | u32 newsid; | |
2267 | int rc; | |
2268 | ||
2269 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
2270 | return -EOPNOTSUPP; | |
2271 | ||
2272 | if (!value || !size) | |
2273 | return -EACCES; | |
2274 | ||
2275 | rc = security_context_to_sid((void*)value, size, &newsid); | |
2276 | if (rc) | |
2277 | return rc; | |
2278 | ||
2279 | isec->sid = newsid; | |
2280 | return 0; | |
2281 | } | |
2282 | ||
2283 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
2284 | { | |
2285 | const int len = sizeof(XATTR_NAME_SELINUX); | |
2286 | if (buffer && len <= buffer_size) | |
2287 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
2288 | return len; | |
2289 | } | |
2290 | ||
2291 | /* file security operations */ | |
2292 | ||
2293 | static int selinux_file_permission(struct file *file, int mask) | |
2294 | { | |
2295 | struct inode *inode = file->f_dentry->d_inode; | |
2296 | ||
2297 | if (!mask) { | |
2298 | /* No permission to check. Existence test. */ | |
2299 | return 0; | |
2300 | } | |
2301 | ||
2302 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ | |
2303 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
2304 | mask |= MAY_APPEND; | |
2305 | ||
2306 | return file_has_perm(current, file, | |
2307 | file_mask_to_av(inode->i_mode, mask)); | |
2308 | } | |
2309 | ||
2310 | static int selinux_file_alloc_security(struct file *file) | |
2311 | { | |
2312 | return file_alloc_security(file); | |
2313 | } | |
2314 | ||
2315 | static void selinux_file_free_security(struct file *file) | |
2316 | { | |
2317 | file_free_security(file); | |
2318 | } | |
2319 | ||
2320 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, | |
2321 | unsigned long arg) | |
2322 | { | |
2323 | int error = 0; | |
2324 | ||
2325 | switch (cmd) { | |
2326 | case FIONREAD: | |
2327 | /* fall through */ | |
2328 | case FIBMAP: | |
2329 | /* fall through */ | |
2330 | case FIGETBSZ: | |
2331 | /* fall through */ | |
2332 | case EXT2_IOC_GETFLAGS: | |
2333 | /* fall through */ | |
2334 | case EXT2_IOC_GETVERSION: | |
2335 | error = file_has_perm(current, file, FILE__GETATTR); | |
2336 | break; | |
2337 | ||
2338 | case EXT2_IOC_SETFLAGS: | |
2339 | /* fall through */ | |
2340 | case EXT2_IOC_SETVERSION: | |
2341 | error = file_has_perm(current, file, FILE__SETATTR); | |
2342 | break; | |
2343 | ||
2344 | /* sys_ioctl() checks */ | |
2345 | case FIONBIO: | |
2346 | /* fall through */ | |
2347 | case FIOASYNC: | |
2348 | error = file_has_perm(current, file, 0); | |
2349 | break; | |
2350 | ||
2351 | case KDSKBENT: | |
2352 | case KDSKBSENT: | |
2353 | error = task_has_capability(current,CAP_SYS_TTY_CONFIG); | |
2354 | break; | |
2355 | ||
2356 | /* default case assumes that the command will go | |
2357 | * to the file's ioctl() function. | |
2358 | */ | |
2359 | default: | |
2360 | error = file_has_perm(current, file, FILE__IOCTL); | |
2361 | ||
2362 | } | |
2363 | return error; | |
2364 | } | |
2365 | ||
2366 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) | |
2367 | { | |
2368 | #ifndef CONFIG_PPC32 | |
2369 | if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { | |
2370 | /* | |
2371 | * We are making executable an anonymous mapping or a | |
2372 | * private file mapping that will also be writable. | |
2373 | * This has an additional check. | |
2374 | */ | |
2375 | int rc = task_has_perm(current, current, PROCESS__EXECMEM); | |
2376 | if (rc) | |
2377 | return rc; | |
2378 | } | |
2379 | #endif | |
2380 | ||
2381 | if (file) { | |
2382 | /* read access is always possible with a mapping */ | |
2383 | u32 av = FILE__READ; | |
2384 | ||
2385 | /* write access only matters if the mapping is shared */ | |
2386 | if (shared && (prot & PROT_WRITE)) | |
2387 | av |= FILE__WRITE; | |
2388 | ||
2389 | if (prot & PROT_EXEC) | |
2390 | av |= FILE__EXECUTE; | |
2391 | ||
2392 | return file_has_perm(current, file, av); | |
2393 | } | |
2394 | return 0; | |
2395 | } | |
2396 | ||
2397 | static int selinux_file_mmap(struct file *file, unsigned long reqprot, | |
2398 | unsigned long prot, unsigned long flags) | |
2399 | { | |
2400 | int rc; | |
2401 | ||
2402 | rc = secondary_ops->file_mmap(file, reqprot, prot, flags); | |
2403 | if (rc) | |
2404 | return rc; | |
2405 | ||
2406 | if (selinux_checkreqprot) | |
2407 | prot = reqprot; | |
2408 | ||
2409 | return file_map_prot_check(file, prot, | |
2410 | (flags & MAP_TYPE) == MAP_SHARED); | |
2411 | } | |
2412 | ||
2413 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
2414 | unsigned long reqprot, | |
2415 | unsigned long prot) | |
2416 | { | |
2417 | int rc; | |
2418 | ||
2419 | rc = secondary_ops->file_mprotect(vma, reqprot, prot); | |
2420 | if (rc) | |
2421 | return rc; | |
2422 | ||
2423 | if (selinux_checkreqprot) | |
2424 | prot = reqprot; | |
2425 | ||
2426 | #ifndef CONFIG_PPC32 | |
db4c9641 SS |
2427 | if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { |
2428 | rc = 0; | |
2429 | if (vma->vm_start >= vma->vm_mm->start_brk && | |
2430 | vma->vm_end <= vma->vm_mm->brk) { | |
2431 | rc = task_has_perm(current, current, | |
2432 | PROCESS__EXECHEAP); | |
2433 | } else if (!vma->vm_file && | |
2434 | vma->vm_start <= vma->vm_mm->start_stack && | |
2435 | vma->vm_end >= vma->vm_mm->start_stack) { | |
2436 | rc = task_has_perm(current, current, PROCESS__EXECSTACK); | |
2437 | } else if (vma->vm_file && vma->anon_vma) { | |
2438 | /* | |
2439 | * We are making executable a file mapping that has | |
2440 | * had some COW done. Since pages might have been | |
2441 | * written, check ability to execute the possibly | |
2442 | * modified content. This typically should only | |
2443 | * occur for text relocations. | |
2444 | */ | |
2445 | rc = file_has_perm(current, vma->vm_file, | |
2446 | FILE__EXECMOD); | |
2447 | } | |