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Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[linux-2.6/linux-mips/linux-dm7025.git] / kernel / auditsc.c
blobc10e7aae04d795714fb8cf4ee9326eff4bf6c472
1 /* auditsc.c -- System-call auditing support
2 * Handles all system-call specific auditing features.
3 *
4 * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
5 * Copyright 2005 Hewlett-Packard Development Company, L.P.
6 * Copyright (C) 2005, 2006 IBM Corporation
7 * All Rights Reserved.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 *
23 * Written by Rickard E. (Rik) Faith <faith@redhat.com>
24 *
25 * Many of the ideas implemented here are from Stephen C. Tweedie,
26 * especially the idea of avoiding a copy by using getname.
27 *
28 * The method for actual interception of syscall entry and exit (not in
29 * this file -- see entry.S) is based on a GPL'd patch written by
30 * okir@suse.de and Copyright 2003 SuSE Linux AG.
31 *
32 * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>,
33 * 2006.
34 *
35 * The support of additional filter rules compares (>, <, >=, <=) was
36 * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005.
37 *
38 * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional
39 * filesystem information.
40 *
41 * Subject and object context labeling support added by <danjones@us.ibm.com>
42 * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance.
43 */
44
45 #include <linux/init.h>
46 #include <asm/types.h>
47 #include <asm/atomic.h>
48 #include <linux/fs.h>
49 #include <linux/namei.h>
50 #include <linux/mm.h>
51 #include <linux/module.h>
52 #include <linux/mount.h>
53 #include <linux/socket.h>
54 #include <linux/mqueue.h>
55 #include <linux/audit.h>
56 #include <linux/personality.h>
57 #include <linux/time.h>
58 #include <linux/netlink.h>
59 #include <linux/compiler.h>
60 #include <asm/unistd.h>
61 #include <linux/security.h>
62 #include <linux/list.h>
63 #include <linux/tty.h>
64 #include <linux/binfmts.h>
65 #include <linux/highmem.h>
66 #include <linux/syscalls.h>
67 #include <linux/inotify.h>
68
69 #include "audit.h"
70
71 /* AUDIT_NAMES is the number of slots we reserve in the audit_context
72 * for saving names from getname(). */
73 #define AUDIT_NAMES 20
74
75 /* Indicates that audit should log the full pathname. */
76 #define AUDIT_NAME_FULL -1
77
78 /* no execve audit message should be longer than this (userspace limits) */
79 #define MAX_EXECVE_AUDIT_LEN 7500
80
81 /* number of audit rules */
82 int audit_n_rules;
83
84 /* determines whether we collect data for signals sent */
85 int audit_signals;
86
87 /* When fs/namei.c:getname() is called, we store the pointer in name and
88 * we don't let putname() free it (instead we free all of the saved
89 * pointers at syscall exit time).
90 *
91 * Further, in fs/namei.c:path_lookup() we store the inode and device. */
92 struct audit_names {
93 const char *name;
94 int name_len; /* number of name's characters to log */
95 unsigned name_put; /* call __putname() for this name */
96 unsigned long ino;
97 dev_t dev;
98 umode_t mode;
99 uid_t uid;
100 gid_t gid;
101 dev_t rdev;
102 u32 osid;
103 };
104
105 struct audit_aux_data {
106 struct audit_aux_data *next;
107 int type;
108 };
109
110 #define AUDIT_AUX_IPCPERM 0
111
112 /* Number of target pids per aux struct. */
113 #define AUDIT_AUX_PIDS 16
114
115 struct audit_aux_data_mq_open {
116 struct audit_aux_data d;
117 int oflag;
118 mode_t mode;
119 struct mq_attr attr;
120 };
121
122 struct audit_aux_data_mq_sendrecv {
123 struct audit_aux_data d;
124 mqd_t mqdes;
125 size_t msg_len;
126 unsigned int msg_prio;
127 struct timespec abs_timeout;
128 };
129
130 struct audit_aux_data_mq_notify {
131 struct audit_aux_data d;
132 mqd_t mqdes;
133 struct sigevent notification;
134 };
135
136 struct audit_aux_data_mq_getsetattr {
137 struct audit_aux_data d;
138 mqd_t mqdes;
139 struct mq_attr mqstat;
140 };
141
142 struct audit_aux_data_ipcctl {
143 struct audit_aux_data d;
144 struct ipc_perm p;
145 unsigned long qbytes;
146 uid_t uid;
147 gid_t gid;
148 mode_t mode;
149 u32 osid;
150 };
151
152 struct audit_aux_data_execve {
153 struct audit_aux_data d;
154 int argc;
155 int envc;
156 struct mm_struct *mm;
157 };
158
159 struct audit_aux_data_socketcall {
160 struct audit_aux_data d;
161 int nargs;
162 unsigned long args[0];
163 };
164
165 struct audit_aux_data_sockaddr {
166 struct audit_aux_data d;
167 int len;
168 char a[0];
169 };
170
171 struct audit_aux_data_fd_pair {
172 struct audit_aux_data d;
173 int fd[2];
174 };
175
176 struct audit_aux_data_pids {
177 struct audit_aux_data d;
178 pid_t target_pid[AUDIT_AUX_PIDS];
179 uid_t target_auid[AUDIT_AUX_PIDS];
180 uid_t target_uid[AUDIT_AUX_PIDS];
181 unsigned int target_sessionid[AUDIT_AUX_PIDS];
182 u32 target_sid[AUDIT_AUX_PIDS];
183 char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
184 int pid_count;
185 };
186
187 struct audit_tree_refs {
188 struct audit_tree_refs *next;
189 struct audit_chunk *c[31];
190 };
191
192 /* The per-task audit context. */
193 struct audit_context {
194 int dummy; /* must be the first element */
195 int in_syscall; /* 1 if task is in a syscall */
196 enum audit_state state;
197 unsigned int serial; /* serial number for record */
198 struct timespec ctime; /* time of syscall entry */
199 int major; /* syscall number */
200 unsigned long argv[4]; /* syscall arguments */
201 int return_valid; /* return code is valid */
202 long return_code;/* syscall return code */
203 int auditable; /* 1 if record should be written */
204 int name_count;
205 struct audit_names names[AUDIT_NAMES];
206 char * filterkey; /* key for rule that triggered record */
207 struct path pwd;
208 struct audit_context *previous; /* For nested syscalls */
209 struct audit_aux_data *aux;
210 struct audit_aux_data *aux_pids;
211
212 /* Save things to print about task_struct */
213 pid_t pid, ppid;
214 uid_t uid, euid, suid, fsuid;
215 gid_t gid, egid, sgid, fsgid;
216 unsigned long personality;
217 int arch;
218
219 pid_t target_pid;
220 uid_t target_auid;
221 uid_t target_uid;
222 unsigned int target_sessionid;
223 u32 target_sid;
224 char target_comm[TASK_COMM_LEN];
225
226 struct audit_tree_refs *trees, *first_trees;
227 int tree_count;
228
229 #if AUDIT_DEBUG
230 int put_count;
231 int ino_count;
232 #endif
233 };
234
235 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
236 static inline int open_arg(int flags, int mask)
237 {
238 int n = ACC_MODE(flags);
239 if (flags & (O_TRUNC | O_CREAT))
240 n |= AUDIT_PERM_WRITE;
241 return n & mask;
242 }
243
244 static int audit_match_perm(struct audit_context *ctx, int mask)
245 {
246 unsigned n = ctx->major;
247 switch (audit_classify_syscall(ctx->arch, n)) {
248 case 0: /* native */
249 if ((mask & AUDIT_PERM_WRITE) &&
250 audit_match_class(AUDIT_CLASS_WRITE, n))
251 return 1;
252 if ((mask & AUDIT_PERM_READ) &&
253 audit_match_class(AUDIT_CLASS_READ, n))
254 return 1;
255 if ((mask & AUDIT_PERM_ATTR) &&
256 audit_match_class(AUDIT_CLASS_CHATTR, n))
257 return 1;
258 return 0;
259 case 1: /* 32bit on biarch */
260 if ((mask & AUDIT_PERM_WRITE) &&
261 audit_match_class(AUDIT_CLASS_WRITE_32, n))
262 return 1;
263 if ((mask & AUDIT_PERM_READ) &&
264 audit_match_class(AUDIT_CLASS_READ_32, n))
265 return 1;
266 if ((mask & AUDIT_PERM_ATTR) &&
267 audit_match_class(AUDIT_CLASS_CHATTR_32, n))
268 return 1;
269 return 0;
270 case 2: /* open */
271 return mask & ACC_MODE(ctx->argv[1]);
272 case 3: /* openat */
273 return mask & ACC_MODE(ctx->argv[2]);
274 case 4: /* socketcall */
275 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
276 case 5: /* execve */
277 return mask & AUDIT_PERM_EXEC;
278 default:
279 return 0;
280 }
281 }
282
283 static int audit_match_filetype(struct audit_context *ctx, int which)
284 {
285 unsigned index = which & ~S_IFMT;
286 mode_t mode = which & S_IFMT;
287 if (index >= ctx->name_count)
288 return 0;
289 if (ctx->names[index].ino == -1)
290 return 0;
291 if ((ctx->names[index].mode ^ mode) & S_IFMT)
292 return 0;
293 return 1;
294 }
295
296 /*
297 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
298 * ->first_trees points to its beginning, ->trees - to the current end of data.
299 * ->tree_count is the number of free entries in array pointed to by ->trees.
300 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
301 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously,
302 * it's going to remain 1-element for almost any setup) until we free context itself.
303 * References in it _are_ dropped - at the same time we free/drop aux stuff.
304 */
305
306 #ifdef CONFIG_AUDIT_TREE
307 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
308 {
309 struct audit_tree_refs *p = ctx->trees;
310 int left = ctx->tree_count;
311 if (likely(left)) {
312 p->c[--left] = chunk;
313 ctx->tree_count = left;
314 return 1;
315 }
316 if (!p)
317 return 0;
318 p = p->next;
319 if (p) {
320 p->c[30] = chunk;
321 ctx->trees = p;
322 ctx->tree_count = 30;
323 return 1;
324 }
325 return 0;
326 }
327
328 static int grow_tree_refs(struct audit_context *ctx)
329 {
330 struct audit_tree_refs *p = ctx->trees;
331 ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
332 if (!ctx->trees) {
333 ctx->trees = p;
334 return 0;
335 }
336 if (p)
337 p->next = ctx->trees;
338 else
339 ctx->first_trees = ctx->trees;
340 ctx->tree_count = 31;
341 return 1;
342 }
343 #endif
344
345 static void unroll_tree_refs(struct audit_context *ctx,
346 struct audit_tree_refs *p, int count)
347 {
348 #ifdef CONFIG_AUDIT_TREE
349 struct audit_tree_refs *q;
350 int n;
351 if (!p) {
352 /* we started with empty chain */
353 p = ctx->first_trees;
354 count = 31;
355 /* if the very first allocation has failed, nothing to do */
356 if (!p)
357 return;
358 }
359 n = count;
360 for (q = p; q != ctx->trees; q = q->next, n = 31) {
361 while (n--) {
362 audit_put_chunk(q->c[n]);
363 q->c[n] = NULL;
364 }
365 }
366 while (n-- > ctx->tree_count) {
367 audit_put_chunk(q->c[n]);
368 q->c[n] = NULL;
369 }
370 ctx->trees = p;
371 ctx->tree_count = count;
372 #endif
373 }
374
375 static void free_tree_refs(struct audit_context *ctx)
376 {
377 struct audit_tree_refs *p, *q;
378 for (p = ctx->first_trees; p; p = q) {
379 q = p->next;
380 kfree(p);
381 }
382 }
383
384 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
385 {
386 #ifdef CONFIG_AUDIT_TREE
387 struct audit_tree_refs *p;
388 int n;
389 if (!tree)
390 return 0;
391 /* full ones */
392 for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
393 for (n = 0; n < 31; n++)
394 if (audit_tree_match(p->c[n], tree))
395 return 1;
396 }
397 /* partial */
398 if (p) {
399 for (n = ctx->tree_count; n < 31; n++)
400 if (audit_tree_match(p->c[n], tree))
401 return 1;
402 }
403 #endif
404 return 0;
405 }
406
407 /* Determine if any context name data matches a rule's watch data */
408 /* Compare a task_struct with an audit_rule. Return 1 on match, 0
409 * otherwise. */
410 static int audit_filter_rules(struct task_struct *tsk,
411 struct audit_krule *rule,
412 struct audit_context *ctx,
413 struct audit_names *name,
414 enum audit_state *state)
415 {
416 int i, j, need_sid = 1;
417 u32 sid;
418
419 for (i = 0; i < rule->field_count; i++) {
420 struct audit_field *f = &rule->fields[i];
421 int result = 0;
422
423 switch (f->type) {
424 case AUDIT_PID:
425 result = audit_comparator(tsk->pid, f->op, f->val);
426 break;
427 case AUDIT_PPID:
428 if (ctx) {
429 if (!ctx->ppid)
430 ctx->ppid = sys_getppid();
431 result = audit_comparator(ctx->ppid, f->op, f->val);
432 }
433 break;
434 case AUDIT_UID:
435 result = audit_comparator(tsk->uid, f->op, f->val);
436 break;
437 case AUDIT_EUID:
438 result = audit_comparator(tsk->euid, f->op, f->val);
439 break;
440 case AUDIT_SUID:
441 result = audit_comparator(tsk->suid, f->op, f->val);
442 break;
443 case AUDIT_FSUID:
444 result = audit_comparator(tsk->fsuid, f->op, f->val);
445 break;
446 case AUDIT_GID:
447 result = audit_comparator(tsk->gid, f->op, f->val);
448 break;
449 case AUDIT_EGID:
450 result = audit_comparator(tsk->egid, f->op, f->val);
451 break;
452 case AUDIT_SGID:
453 result = audit_comparator(tsk->sgid, f->op, f->val);
454 break;
455 case AUDIT_FSGID:
456 result = audit_comparator(tsk->fsgid, f->op, f->val);
457 break;
458 case AUDIT_PERS:
459 result = audit_comparator(tsk->personality, f->op, f->val);
460 break;
461 case AUDIT_ARCH:
462 if (ctx)
463 result = audit_comparator(ctx->arch, f->op, f->val);
464 break;
465
466 case AUDIT_EXIT:
467 if (ctx && ctx->return_valid)
468 result = audit_comparator(ctx->return_code, f->op, f->val);
469 break;
470 case AUDIT_SUCCESS:
471 if (ctx && ctx->return_valid) {
472 if (f->val)
473 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
474 else
475 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
476 }
477 break;
478 case AUDIT_DEVMAJOR:
479 if (name)
480 result = audit_comparator(MAJOR(name->dev),
481 f->op, f->val);
482 else if (ctx) {
483 for (j = 0; j < ctx->name_count; j++) {
484 if (audit_comparator(MAJOR(ctx->names[j].dev), f->op, f->val)) {
485 ++result;
486 break;
487 }
488 }
489 }
490 break;
491 case AUDIT_DEVMINOR:
492 if (name)
493 result = audit_comparator(MINOR(name->dev),
494 f->op, f->val);
495 else if (ctx) {
496 for (j = 0; j < ctx->name_count; j++) {
497 if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) {
498 ++result;
499 break;
500 }
501 }
502 }
503 break;
504 case AUDIT_INODE:
505 if (name)
506 result = (name->ino == f->val);
507 else if (ctx) {
508 for (j = 0; j < ctx->name_count; j++) {
509 if (audit_comparator(ctx->names[j].ino, f->op, f->val)) {
510 ++result;
511 break;
512 }
513 }
514 }
515 break;
516 case AUDIT_WATCH:
517 if (name && rule->watch->ino != (unsigned long)-1)
518 result = (name->dev == rule->watch->dev &&
519 name->ino == rule->watch->ino);
520 break;
521 case AUDIT_DIR:
522 if (ctx)
523 result = match_tree_refs(ctx, rule->tree);
524 break;
525 case AUDIT_LOGINUID:
526 result = 0;
527 if (ctx)
528 result = audit_comparator(tsk->loginuid, f->op, f->val);
529 break;
530 case AUDIT_SUBJ_USER:
531 case AUDIT_SUBJ_ROLE:
532 case AUDIT_SUBJ_TYPE:
533 case AUDIT_SUBJ_SEN:
534 case AUDIT_SUBJ_CLR:
535 /* NOTE: this may return negative values indicating
536 a temporary error. We simply treat this as a
537 match for now to avoid losing information that
538 may be wanted. An error message will also be
539 logged upon error */
540 if (f->lsm_rule) {
541 if (need_sid) {
542 security_task_getsecid(tsk, &sid);
543 need_sid = 0;
544 }
545 result = security_audit_rule_match(sid, f->type,
546 f->op,
547 f->lsm_rule,
548 ctx);
549 }
550 break;
551 case AUDIT_OBJ_USER:
552 case AUDIT_OBJ_ROLE:
553 case AUDIT_OBJ_TYPE:
554 case AUDIT_OBJ_LEV_LOW:
555 case AUDIT_OBJ_LEV_HIGH:
556 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
557 also applies here */
558 if (f->lsm_rule) {
559 /* Find files that match */
560 if (name) {
561 result = security_audit_rule_match(
562 name->osid, f->type, f->op,
563 f->lsm_rule, ctx);
564 } else if (ctx) {
565 for (j = 0; j < ctx->name_count; j++) {
566 if (security_audit_rule_match(
567 ctx->names[j].osid,
568 f->type, f->op,
569 f->lsm_rule, ctx)) {
570 ++result;
571 break;
572 }
573 }
574 }
575 /* Find ipc objects that match */
576 if (ctx) {
577 struct audit_aux_data *aux;
578 for (aux = ctx->aux; aux;
579 aux = aux->next) {
580 if (aux->type == AUDIT_IPC) {
581 struct audit_aux_data_ipcctl *axi = (void *)aux;
582 if (security_audit_rule_match(axi->osid, f->type, f->op, f->lsm_rule, ctx)) {
583 ++result;
584 break;
585 }
586 }
587 }
588 }
589 }
590 break;
591 case AUDIT_ARG0:
592 case AUDIT_ARG1:
593 case AUDIT_ARG2:
594 case AUDIT_ARG3:
595 if (ctx)
596 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
597 break;
598 case AUDIT_FILTERKEY:
599 /* ignore this field for filtering */
600 result = 1;
601 break;
602 case AUDIT_PERM:
603 result = audit_match_perm(ctx, f->val);
604 break;
605 case AUDIT_FILETYPE:
606 result = audit_match_filetype(ctx, f->val);
607 break;
608 }
609
610 if (!result)
611 return 0;
612 }
613 if (rule->filterkey)
614 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
615 switch (rule->action) {
616 case AUDIT_NEVER: *state = AUDIT_DISABLED; break;
617 case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break;
618 }
619 return 1;
620 }
621
622 /* At process creation time, we can determine if system-call auditing is
623 * completely disabled for this task. Since we only have the task
624 * structure at this point, we can only check uid and gid.
625 */
626 static enum audit_state audit_filter_task(struct task_struct *tsk)
627 {
628 struct audit_entry *e;
629 enum audit_state state;
630
631 rcu_read_lock();
632 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
633 if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) {
634 rcu_read_unlock();
635 return state;
636 }
637 }
638 rcu_read_unlock();
639 return AUDIT_BUILD_CONTEXT;
640 }
641
642 /* At syscall entry and exit time, this filter is called if the
643 * audit_state is not low enough that auditing cannot take place, but is
644 * also not high enough that we already know we have to write an audit
645 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
646 */
647 static enum audit_state audit_filter_syscall(struct task_struct *tsk,
648 struct audit_context *ctx,
649 struct list_head *list)
650 {
651 struct audit_entry *e;
652 enum audit_state state;
653
654 if (audit_pid && tsk->tgid == audit_pid)
655 return AUDIT_DISABLED;
656
657 rcu_read_lock();
658 if (!list_empty(list)) {
659 int word = AUDIT_WORD(ctx->major);
660 int bit = AUDIT_BIT(ctx->major);
661
662 list_for_each_entry_rcu(e, list, list) {
663 if ((e->rule.mask[word] & bit) == bit &&
664 audit_filter_rules(tsk, &e->rule, ctx, NULL,
665 &state)) {
666 rcu_read_unlock();
667 return state;
668 }
669 }
670 }
671 rcu_read_unlock();
672 return AUDIT_BUILD_CONTEXT;
673 }
674
675 /* At syscall exit time, this filter is called if any audit_names[] have been
676 * collected during syscall processing. We only check rules in sublists at hash
677 * buckets applicable to the inode numbers in audit_names[].
678 * Regarding audit_state, same rules apply as for audit_filter_syscall().
679 */
680 enum audit_state audit_filter_inodes(struct task_struct *tsk,
681 struct audit_context *ctx)
682 {
683 int i;
684 struct audit_entry *e;
685 enum audit_state state;
686
687 if (audit_pid && tsk->tgid == audit_pid)
688 return AUDIT_DISABLED;
689
690 rcu_read_lock();
691 for (i = 0; i < ctx->name_count; i++) {
692 int word = AUDIT_WORD(ctx->major);
693 int bit = AUDIT_BIT(ctx->major);
694 struct audit_names *n = &ctx->names[i];
695 int h = audit_hash_ino((u32)n->ino);
696 struct list_head *list = &audit_inode_hash[h];
697
698 if (list_empty(list))
699 continue;
700
701 list_for_each_entry_rcu(e, list, list) {
702 if ((e->rule.mask[word] & bit) == bit &&
703 audit_filter_rules(tsk, &e->rule, ctx, n, &state)) {
704 rcu_read_unlock();
705 return state;
706 }
707 }
708 }
709 rcu_read_unlock();
710 return AUDIT_BUILD_CONTEXT;
711 }
712
713 void audit_set_auditable(struct audit_context *ctx)
714 {
715 ctx->auditable = 1;
716 }
717
718 static inline struct audit_context *audit_get_context(struct task_struct *tsk,
719 int return_valid,
720 int return_code)
721 {
722 struct audit_context *context = tsk->audit_context;
723
724 if (likely(!context))
725 return NULL;
726 context->return_valid = return_valid;
727
728 /*
729 * we need to fix up the return code in the audit logs if the actual
730 * return codes are later going to be fixed up by the arch specific
731 * signal handlers
732 *
733 * This is actually a test for:
734 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
735 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
736 *
737 * but is faster than a bunch of ||
738 */
739 if (unlikely(return_code <= -ERESTARTSYS) &&
740 (return_code >= -ERESTART_RESTARTBLOCK) &&
741 (return_code != -ENOIOCTLCMD))
742 context->return_code = -EINTR;
743 else
744 context->return_code = return_code;
745
746 if (context->in_syscall && !context->dummy && !context->auditable) {
747 enum audit_state state;
748
749 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
750 if (state == AUDIT_RECORD_CONTEXT) {
751 context->auditable = 1;
752 goto get_context;
753 }
754
755 state = audit_filter_inodes(tsk, context);
756 if (state == AUDIT_RECORD_CONTEXT)
757 context->auditable = 1;
758
759 }
760
761 get_context:
762
763 tsk->audit_context = NULL;
764 return context;
765 }
766
767 static inline void audit_free_names(struct audit_context *context)
768 {
769 int i;
770
771 #if AUDIT_DEBUG == 2
772 if (context->auditable
773 ||context->put_count + context->ino_count != context->name_count) {
774 printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
775 " name_count=%d put_count=%d"
776 " ino_count=%d [NOT freeing]\n",
777 __FILE__, __LINE__,
778 context->serial, context->major, context->in_syscall,
779 context->name_count, context->put_count,
780 context->ino_count);
781 for (i = 0; i < context->name_count; i++) {
782 printk(KERN_ERR "names[%d] = %p = %s\n", i,
783 context->names[i].name,
784 context->names[i].name ?: "(null)");
785 }
786 dump_stack();
787 return;
788 }
789 #endif
790 #if AUDIT_DEBUG
791 context->put_count = 0;
792 context->ino_count = 0;
793 #endif
794
795 for (i = 0; i < context->name_count; i++) {
796 if (context->names[i].name && context->names[i].name_put)
797 __putname(context->names[i].name);
798 }
799 context->name_count = 0;
800 path_put(&context->pwd);
801 context->pwd.dentry = NULL;
802 context->pwd.mnt = NULL;
803 }
804
805 static inline void audit_free_aux(struct audit_context *context)
806 {
807 struct audit_aux_data *aux;
808
809 while ((aux = context->aux)) {
810 context->aux = aux->next;
811 kfree(aux);
812 }
813 while ((aux = context->aux_pids)) {
814 context->aux_pids = aux->next;
815 kfree(aux);
816 }
817 }
818
819 static inline void audit_zero_context(struct audit_context *context,
820 enum audit_state state)
821 {
822 memset(context, 0, sizeof(*context));
823 context->state = state;
824 }
825
826 static inline struct audit_context *audit_alloc_context(enum audit_state state)
827 {
828 struct audit_context *context;
829
830 if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
831 return NULL;
832 audit_zero_context(context, state);
833 return context;
834 }
835
836 /**
837 * audit_alloc - allocate an audit context block for a task
838 * @tsk: task
839 *
840 * Filter on the task information and allocate a per-task audit context
841 * if necessary. Doing so turns on system call auditing for the
842 * specified task. This is called from copy_process, so no lock is
843 * needed.
844 */
845 int audit_alloc(struct task_struct *tsk)
846 {
847 struct audit_context *context;
848 enum audit_state state;
849
850 if (likely(!audit_ever_enabled))
851 return 0; /* Return if not auditing. */
852
853 state = audit_filter_task(tsk);
854 if (likely(state == AUDIT_DISABLED))
855 return 0;
856
857 if (!(context = audit_alloc_context(state))) {
858 audit_log_lost("out of memory in audit_alloc");
859 return -ENOMEM;
860 }
861
862 tsk->audit_context = context;
863 set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
864 return 0;
865 }
866
867 static inline void audit_free_context(struct audit_context *context)
868 {
869 struct audit_context *previous;
870 int count = 0;
871
872 do {
873 previous = context->previous;
874 if (previous || (count && count < 10)) {
875 ++count;
876 printk(KERN_ERR "audit(:%d): major=%d name_count=%d:"
877 " freeing multiple contexts (%d)\n",
878 context->serial, context->major,
879 context->name_count, count);
880 }
881 audit_free_names(context);
882 unroll_tree_refs(context, NULL, 0);
883 free_tree_refs(context);
884 audit_free_aux(context);
885 kfree(context->filterkey);
886 kfree(context);
887 context = previous;
888 } while (context);
889 if (count >= 10)
890 printk(KERN_ERR "audit: freed %d contexts\n", count);
891 }
892
893 void audit_log_task_context(struct audit_buffer *ab)
894 {
895 char *ctx = NULL;
896 unsigned len;
897 int error;
898 u32 sid;
899
900 security_task_getsecid(current, &sid);
901 if (!sid)
902 return;
903
904 error = security_secid_to_secctx(sid, &ctx, &len);
905 if (error) {
906 if (error != -EINVAL)
907 goto error_path;
908 return;
909 }
910
911 audit_log_format(ab, " subj=%s", ctx);
912 security_release_secctx(ctx, len);
913 return;
914
915 error_path:
916 audit_panic("error in audit_log_task_context");
917 return;
918 }
919
920 EXPORT_SYMBOL(audit_log_task_context);
921
922 static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
923 {
924 char name[sizeof(tsk->comm)];
925 struct mm_struct *mm = tsk->mm;
926 struct vm_area_struct *vma;
927
928 /* tsk == current */
929
930 get_task_comm(name, tsk);
931 audit_log_format(ab, " comm=");
932 audit_log_untrustedstring(ab, name);
933
934 if (mm) {
935 down_read(&mm->mmap_sem);
936 vma = mm->mmap;
937 while (vma) {
938 if ((vma->vm_flags & VM_EXECUTABLE) &&
939 vma->vm_file) {
940 audit_log_d_path(ab, "exe=",
941 &vma->vm_file->f_path);
942 break;
943 }
944 vma = vma->vm_next;
945 }
946 up_read(&mm->mmap_sem);
947 }
948 audit_log_task_context(ab);
949 }
950
951 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
952 uid_t auid, uid_t uid, unsigned int sessionid,
953 u32 sid, char *comm)
954 {
955 struct audit_buffer *ab;
956 char *ctx = NULL;
957 u32 len;
958 int rc = 0;
959
960 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
961 if (!ab)
962 return rc;
963
964 audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid,
965 uid, sessionid);
966 if (security_secid_to_secctx(sid, &ctx, &len)) {
967 audit_log_format(ab, " obj=(none)");
968 rc = 1;
969 } else {
970 audit_log_format(ab, " obj=%s", ctx);
971 security_release_secctx(ctx, len);
972 }
973 audit_log_format(ab, " ocomm=");
974 audit_log_untrustedstring(ab, comm);
975 audit_log_end(ab);
976
977 return rc;
978 }
979
980 /*
981 * to_send and len_sent accounting are very loose estimates. We aren't
982 * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being
983 * within about 500 bytes (next page boundry)
984 *
985 * why snprintf? an int is up to 12 digits long. if we just assumed when
986 * logging that a[%d]= was going to be 16 characters long we would be wasting
987 * space in every audit message. In one 7500 byte message we can log up to
988 * about 1000 min size arguments. That comes down to about 50% waste of space
989 * if we didn't do the snprintf to find out how long arg_num_len was.
990 */
991 static int audit_log_single_execve_arg(struct audit_context *context,
992 struct audit_buffer **ab,
993 int arg_num,
994 size_t *len_sent,
995 const char __user *p,
996 char *buf)
997 {
998 char arg_num_len_buf[12];
999 const char __user *tmp_p = p;
1000 /* how many digits are in arg_num? 3 is the length of a=\n */
1001 size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 3;
1002 size_t len, len_left, to_send;
1003 size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN;
1004 unsigned int i, has_cntl = 0, too_long = 0;
1005 int ret;
1006
1007 /* strnlen_user includes the null we don't want to send */
1008 len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1009
1010 /*
1011 * We just created this mm, if we can't find the strings
1012 * we just copied into it something is _very_ wrong. Similar
1013 * for strings that are too long, we should not have created
1014 * any.
1015 */
1016 if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
1017 WARN_ON(1);
1018 send_sig(SIGKILL, current, 0);
1019 return -1;
1020 }
1021
1022 /* walk the whole argument looking for non-ascii chars */
1023 do {
1024 if (len_left > MAX_EXECVE_AUDIT_LEN)
1025 to_send = MAX_EXECVE_AUDIT_LEN;
1026 else
1027 to_send = len_left;
1028 ret = copy_from_user(buf, tmp_p, to_send);
1029 /*
1030 * There is no reason for this copy to be short. We just
1031 * copied them here, and the mm hasn't been exposed to user-
1032 * space yet.
1033 */
1034 if (ret) {
1035 WARN_ON(1);
1036 send_sig(SIGKILL, current, 0);
1037 return -1;
1038 }
1039 buf[to_send] = '\0';
1040 has_cntl = audit_string_contains_control(buf, to_send);
1041 if (has_cntl) {
1042 /*
1043 * hex messages get logged as 2 bytes, so we can only
1044 * send half as much in each message
1045 */
1046 max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2;
1047 break;
1048 }
1049 len_left -= to_send;
1050 tmp_p += to_send;
1051 } while (len_left > 0);
1052
1053 len_left = len;
1054
1055 if (len > max_execve_audit_len)
1056 too_long = 1;
1057
1058 /* rewalk the argument actually logging the message */
1059 for (i = 0; len_left > 0; i++) {
1060 int room_left;
1061
1062 if (len_left > max_execve_audit_len)
1063 to_send = max_execve_audit_len;
1064 else
1065 to_send = len_left;
1066
1067 /* do we have space left to send this argument in this ab? */
1068 room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent;
1069 if (has_cntl)
1070 room_left -= (to_send * 2);
1071 else
1072 room_left -= to_send;
1073 if (room_left < 0) {
1074 *len_sent = 0;
1075 audit_log_end(*ab);
1076 *ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE);
1077 if (!*ab)
1078 return 0;
1079 }
1080
1081 /*
1082 * first record needs to say how long the original string was
1083 * so we can be sure nothing was lost.
1084 */
1085 if ((i == 0) && (too_long))
1086 audit_log_format(*ab, "a%d_len=%zu ", arg_num,
1087 has_cntl ? 2*len : len);
1088
1089 /*
1090 * normally arguments are small enough to fit and we already
1091 * filled buf above when we checked for control characters
1092 * so don't bother with another copy_from_user
1093 */
1094 if (len >= max_execve_audit_len)
1095 ret = copy_from_user(buf, p, to_send);
1096 else
1097 ret = 0;
1098 if (ret) {
1099 WARN_ON(1);
1100 send_sig(SIGKILL, current, 0);
1101 return -1;
1102 }
1103 buf[to_send] = '\0';
1104
1105 /* actually log it */
1106 audit_log_format(*ab, "a%d", arg_num);
1107 if (too_long)
1108 audit_log_format(*ab, "[%d]", i);
1109 audit_log_format(*ab, "=");
1110 if (has_cntl)
1111 audit_log_n_hex(*ab, buf, to_send);
1112 else
1113 audit_log_format(*ab, "\"%s\"", buf);
1114 audit_log_format(*ab, "\n");
1115
1116 p += to_send;
1117 len_left -= to_send;
1118 *len_sent += arg_num_len;
1119 if (has_cntl)
1120 *len_sent += to_send * 2;
1121 else
1122 *len_sent += to_send;
1123 }
1124 /* include the null we didn't log */
1125 return len + 1;
1126 }
1127
1128 static void audit_log_execve_info(struct audit_context *context,
1129 struct audit_buffer **ab,
1130 struct audit_aux_data_execve *axi)
1131 {
1132 int i;
1133 size_t len, len_sent = 0;
1134 const char __user *p;
1135 char *buf;
1136
1137 if (axi->mm != current->mm)
1138 return; /* execve failed, no additional info */
1139
1140 p = (const char __user *)axi->mm->arg_start;
1141
1142 audit_log_format(*ab, "argc=%d ", axi->argc);
1143
1144 /*
1145 * we need some kernel buffer to hold the userspace args. Just
1146 * allocate one big one rather than allocating one of the right size
1147 * for every single argument inside audit_log_single_execve_arg()
1148 * should be <8k allocation so should be pretty safe.
1149 */
1150 buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1151 if (!buf) {
1152 audit_panic("out of memory for argv string\n");
1153 return;
1154 }
1155
1156 for (i = 0; i < axi->argc; i++) {
1157 len = audit_log_single_execve_arg(context, ab, i,
1158 &len_sent, p, buf);
1159 if (len <= 0)
1160 break;
1161 p += len;
1162 }
1163 kfree(buf);
1164 }
1165
1166 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
1167 {
1168 int i, call_panic = 0;
1169 struct audit_buffer *ab;
1170 struct audit_aux_data *aux;
1171 const char *tty;
1172
1173 /* tsk == current */
1174 context->pid = tsk->pid;
1175 if (!context->ppid)
1176 context->ppid = sys_getppid();
1177 context->uid = tsk->uid;
1178 context->gid = tsk->gid;
1179 context->euid = tsk->euid;
1180 context->suid = tsk->suid;
1181 context->fsuid = tsk->fsuid;
1182 context->egid = tsk->egid;
1183 context->sgid = tsk->sgid;
1184 context->fsgid = tsk->fsgid;
1185 context->personality = tsk->personality;
1186
1187 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1188 if (!ab)
1189 return; /* audit_panic has been called */
1190 audit_log_format(ab, "arch=%x syscall=%d",
1191 context->arch, context->major);
1192 if (context->personality != PER_LINUX)
1193 audit_log_format(ab, " per=%lx", context->personality);
1194 if (context->return_valid)
1195 audit_log_format(ab, " success=%s exit=%ld",
1196 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
1197 context->return_code);
1198
1199 mutex_lock(&tty_mutex);
1200 read_lock(&tasklist_lock);
1201 if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
1202 tty = tsk->signal->tty->name;
1203 else
1204 tty = "(none)";
1205 read_unlock(&tasklist_lock);
1206 audit_log_format(ab,
1207 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
1208 " ppid=%d pid=%d auid=%u uid=%u gid=%u"
1209 " euid=%u suid=%u fsuid=%u"
1210 " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
1211 context->argv[0],
1212 context->argv[1],
1213 context->argv[2],
1214 context->argv[3],
1215 context->name_count,
1216 context->ppid,
1217 context->pid,
1218 tsk->loginuid,
1219 context->uid,
1220 context->gid,
1221 context->euid, context->suid, context->fsuid,
1222 context->egid, context->sgid, context->fsgid, tty,
1223 tsk->sessionid);
1224
1225 mutex_unlock(&tty_mutex);
1226
1227 audit_log_task_info(ab, tsk);
1228 if (context->filterkey) {
1229 audit_log_format(ab, " key=");
1230 audit_log_untrustedstring(ab, context->filterkey);
1231 } else
1232 audit_log_format(ab, " key=(null)");
1233 audit_log_end(ab);
1234
1235 for (aux = context->aux; aux; aux = aux->next) {
1236
1237 ab = audit_log_start(context, GFP_KERNEL, aux->type);
1238 if (!ab)
1239 continue; /* audit_panic has been called */
1240
1241 switch (aux->type) {
1242 case AUDIT_MQ_OPEN: {
1243 struct audit_aux_data_mq_open *axi = (void *)aux;
1244 audit_log_format(ab,
1245 "oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld "
1246 "mq_msgsize=%ld mq_curmsgs=%ld",
1247 axi->oflag, axi->mode, axi->attr.mq_flags,
1248 axi->attr.mq_maxmsg, axi->attr.mq_msgsize,
1249 axi->attr.mq_curmsgs);
1250 break; }
1251
1252 case AUDIT_MQ_SENDRECV: {
1253 struct audit_aux_data_mq_sendrecv *axi = (void *)aux;
1254 audit_log_format(ab,
1255 "mqdes=%d msg_len=%zd msg_prio=%u "
1256 "abs_timeout_sec=%ld abs_timeout_nsec=%ld",
1257 axi->mqdes, axi->msg_len, axi->msg_prio,
1258 axi->abs_timeout.tv_sec, axi->abs_timeout.tv_nsec);
1259 break; }
1260
1261 case AUDIT_MQ_NOTIFY: {
1262 struct audit_aux_data_mq_notify *axi = (void *)aux;
1263 audit_log_format(ab,
1264 "mqdes=%d sigev_signo=%d",
1265 axi->mqdes,
1266 axi->notification.sigev_signo);
1267 break; }
1268
1269 case AUDIT_MQ_GETSETATTR: {
1270 struct audit_aux_data_mq_getsetattr *axi = (void *)aux;
1271 audit_log_format(ab,
1272 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1273 "mq_curmsgs=%ld ",
1274 axi->mqdes,
1275 axi->mqstat.mq_flags, axi->mqstat.mq_maxmsg,
1276 axi->mqstat.mq_msgsize, axi->mqstat.mq_curmsgs);
1277 break; }
1278
1279 case AUDIT_IPC: {
1280 struct audit_aux_data_ipcctl *axi = (void *)aux;
1281 audit_log_format(ab,
1282 "ouid=%u ogid=%u mode=%#o",
1283 axi->uid, axi->gid, axi->mode);
1284 if (axi->osid != 0) {
1285 char *ctx = NULL;
1286 u32 len;
1287 if (security_secid_to_secctx(
1288 axi->osid, &ctx, &len)) {
1289 audit_log_format(ab, " osid=%u",
1290 axi->osid);
1291 call_panic = 1;
1292 } else {
1293 audit_log_format(ab, " obj=%s", ctx);
1294 security_release_secctx(ctx, len);
1295 }
1296 }
1297 break; }
1298
1299 case AUDIT_IPC_SET_PERM: {
1300 struct audit_aux_data_ipcctl *axi = (void *)aux;
1301 audit_log_format(ab,
1302 "qbytes=%lx ouid=%u ogid=%u mode=%#o",
1303 axi->qbytes, axi->uid, axi->gid, axi->mode);
1304 break; }
1305
1306 case AUDIT_EXECVE: {
1307 struct audit_aux_data_execve *axi = (void *)aux;
1308 audit_log_execve_info(context, &ab, axi);
1309 break; }
1310
1311 case AUDIT_SOCKETCALL: {
1312 struct audit_aux_data_socketcall *axs = (void *)aux;
1313 audit_log_format(ab, "nargs=%d", axs->nargs);
1314 for (i=0; i<axs->nargs; i++)
1315 audit_log_format(ab, " a%d=%lx", i, axs->args[i]);
1316 break; }
1317
1318 case AUDIT_SOCKADDR: {
1319 struct audit_aux_data_sockaddr *axs = (void *)aux;
1320
1321 audit_log_format(ab, "saddr=");
1322 audit_log_n_hex(ab, axs->a, axs->len);
1323 break; }
1324
1325 case AUDIT_FD_PAIR: {
1326 struct audit_aux_data_fd_pair *axs = (void *)aux;
1327 audit_log_format(ab, "fd0=%d fd1=%d", axs->fd[0], axs->fd[1]);
1328 break; }
1329
1330 }
1331 audit_log_end(ab);
1332 }
1333
1334 for (aux = context->aux_pids; aux; aux = aux->next) {
1335 struct audit_aux_data_pids *axs = (void *)aux;
1336
1337 for (i = 0; i < axs->pid_count; i++)
1338 if (audit_log_pid_context(context, axs->target_pid[i],
1339 axs->target_auid[i],
1340 axs->target_uid[i],
1341 axs->target_sessionid[i],
1342 axs->target_sid[i],
1343 axs->target_comm[i]))
1344 call_panic = 1;
1345 }
1346
1347 if (context->target_pid &&
1348 audit_log_pid_context(context, context->target_pid,
1349 context->target_auid, context->target_uid,
1350 context->target_sessionid,
1351 context->target_sid, context->target_comm))
1352 call_panic = 1;
1353
1354 if (context->pwd.dentry && context->pwd.mnt) {
1355 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1356 if (ab) {
1357 audit_log_d_path(ab, "cwd=", &context->pwd);
1358 audit_log_end(ab);
1359 }
1360 }
1361 for (i = 0; i < context->name_count; i++) {
1362 struct audit_names *n = &context->names[i];
1363
1364 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1365 if (!ab)
1366 continue; /* audit_panic has been called */
1367
1368 audit_log_format(ab, "item=%d", i);
1369
1370 if (n->name) {
1371 switch(n->name_len) {
1372 case AUDIT_NAME_FULL:
1373 /* log the full path */
1374 audit_log_format(ab, " name=");
1375 audit_log_untrustedstring(ab, n->name);
1376 break;
1377 case 0:
1378 /* name was specified as a relative path and the
1379 * directory component is the cwd */
1380 audit_log_d_path(ab, " name=", &context->pwd);
1381 break;
1382 default:
1383 /* log the name's directory component */
1384 audit_log_format(ab, " name=");
1385 audit_log_n_untrustedstring(ab, n->name,
1386 n->name_len);
1387 }
1388 } else
1389 audit_log_format(ab, " name=(null)");
1390
1391 if (n->ino != (unsigned long)-1) {
1392 audit_log_format(ab, " inode=%lu"
1393 " dev=%02x:%02x mode=%#o"
1394 " ouid=%u ogid=%u rdev=%02x:%02x",
1395 n->ino,
1396 MAJOR(n->dev),
1397 MINOR(n->dev),
1398 n->mode,
1399 n->uid,
1400 n->gid,
1401 MAJOR(n->rdev),
1402 MINOR(n->rdev));
1403 }
1404 if (n->osid != 0) {
1405 char *ctx = NULL;
1406 u32 len;
1407 if (security_secid_to_secctx(
1408 n->osid, &ctx, &len)) {
1409 audit_log_format(ab, " osid=%u", n->osid);
1410 call_panic = 2;
1411 } else {
1412 audit_log_format(ab, " obj=%s", ctx);
1413 security_release_secctx(ctx, len);
1414 }
1415 }
1416
1417 audit_log_end(ab);
1418 }
1419
1420 /* Send end of event record to help user space know we are finished */
1421 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1422 if (ab)
1423 audit_log_end(ab);
1424 if (call_panic)
1425 audit_panic("error converting sid to string");
1426 }
1427
1428 /**
1429 * audit_free - free a per-task audit context
1430 * @tsk: task whose audit context block to free
1431 *
1432 * Called from copy_process and do_exit
1433 */
1434 void audit_free(struct task_struct *tsk)
1435 {
1436 struct audit_context *context;
1437
1438 context = audit_get_context(tsk, 0, 0);
1439 if (likely(!context))
1440 return;
1441
1442 /* Check for system calls that do not go through the exit
1443 * function (e.g., exit_group), then free context block.
1444 * We use GFP_ATOMIC here because we might be doing this
1445 * in the context of the idle thread */
1446 /* that can happen only if we are called from do_exit() */
1447 if (context->in_syscall && context->auditable)
1448 audit_log_exit(context, tsk);
1449
1450 audit_free_context(context);
1451 }
1452
1453 /**
1454 * audit_syscall_entry - fill in an audit record at syscall entry
1455 * @tsk: task being audited
1456 * @arch: architecture type
1457 * @major: major syscall type (function)
1458 * @a1: additional syscall register 1
1459 * @a2: additional syscall register 2
1460 * @a3: additional syscall register 3
1461 * @a4: additional syscall register 4
1462 *
1463 * Fill in audit context at syscall entry. This only happens if the
1464 * audit context was created when the task was created and the state or
1465 * filters demand the audit context be built. If the state from the
1466 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1467 * then the record will be written at syscall exit time (otherwise, it
1468 * will only be written if another part of the kernel requests that it
1469 * be written).
1470 */
1471 void audit_syscall_entry(int arch, int major,
1472 unsigned long a1, unsigned long a2,
1473 unsigned long a3, unsigned long a4)
1474 {
1475 struct task_struct *tsk = current;
1476 struct audit_context *context = tsk->audit_context;
1477 enum audit_state state;
1478
1479 BUG_ON(!context);
1480
1481 /*
1482 * This happens only on certain architectures that make system
1483 * calls in kernel_thread via the entry.S interface, instead of
1484 * with direct calls. (If you are porting to a new
1485 * architecture, hitting this condition can indicate that you
1486 * got the _exit/_leave calls backward in entry.S.)
1487 *
1488 * i386 no
1489 * x86_64 no
1490 * ppc64 yes (see arch/powerpc/platforms/iseries/misc.S)
1491 *
1492 * This also happens with vm86 emulation in a non-nested manner
1493 * (entries without exits), so this case must be caught.
1494 */
1495 if (context->in_syscall) {
1496 struct audit_context *newctx;
1497
1498 #if AUDIT_DEBUG
1499 printk(KERN_ERR
1500 "audit(:%d) pid=%d in syscall=%d;"
1501 " entering syscall=%d\n",
1502 context->serial, tsk->pid, context->major, major);
1503 #endif
1504 newctx = audit_alloc_context(context->state);
1505 if (newctx) {
1506 newctx->previous = context;
1507 context = newctx;
1508 tsk->audit_context = newctx;
1509 } else {
1510 /* If we can't alloc a new context, the best we
1511 * can do is to leak memory (any pending putname
1512 * will be lost). The only other alternative is
1513 * to abandon auditing. */
1514 audit_zero_context(context, context->state);
1515 }
1516 }
1517 BUG_ON(context->in_syscall || context->name_count);
1518
1519 if (!audit_enabled)
1520 return;
1521
1522 context->arch = arch;
1523 context->major = major;
1524 context->argv[0] = a1;
1525 context->argv[1] = a2;
1526 context->argv[2] = a3;
1527 context->argv[3] = a4;
1528
1529 state = context->state;
1530 context->dummy = !audit_n_rules;
1531 if (!context->dummy && (state == AUDIT_SETUP_CONTEXT || state == AUDIT_BUILD_CONTEXT))
1532 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1533 if (likely(state == AUDIT_DISABLED))
1534 return;
1535
1536 context->serial = 0;
1537 context->ctime = CURRENT_TIME;
1538 context->in_syscall = 1;
1539 context->auditable = !!(state == AUDIT_RECORD_CONTEXT);
1540 context->ppid = 0;
1541 }
1542
1543 /**
1544 * audit_syscall_exit - deallocate audit context after a system call
1545 * @tsk: task being audited
1546 * @valid: success/failure flag
1547 * @return_code: syscall return value
1548 *
1549 * Tear down after system call. If the audit context has been marked as
1550 * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1551 * filtering, or because some other part of the kernel write an audit
1552 * message), then write out the syscall information. In call cases,
1553 * free the names stored from getname().
1554 */
1555 void audit_syscall_exit(int valid, long return_code)
1556 {
1557 struct task_struct *tsk = current;
1558 struct audit_context *context;
1559
1560 context = audit_get_context(tsk, valid, return_code);
1561
1562 if (likely(!context))
1563 return;
1564
1565 if (context->in_syscall && context->auditable)
1566 audit_log_exit(context, tsk);
1567
1568 context->in_syscall = 0;
1569 context->auditable = 0;
1570
1571 if (context->previous) {
1572 struct audit_context *new_context = context->previous;
1573 context->previous = NULL;
1574 audit_free_context(context);
1575 tsk->audit_context = new_context;
1576 } else {
1577 audit_free_names(context);
1578 unroll_tree_refs(context, NULL, 0);
1579 audit_free_aux(context);
1580 context->aux = NULL;
1581 context->aux_pids = NULL;
1582 context->target_pid = 0;
1583 context->target_sid = 0;
1584 kfree(context->filterkey);
1585 context->filterkey = NULL;
1586 tsk->audit_context = context;
1587 }
1588 }
1589
1590 static inline void handle_one(const struct inode *inode)
1591 {
1592 #ifdef CONFIG_AUDIT_TREE
1593 struct audit_context *context;
1594 struct audit_tree_refs *p;
1595 struct audit_chunk *chunk;
1596 int count;
1597 if (likely(list_empty(&inode->inotify_watches)))
1598 return;
1599 context = current->audit_context;
1600 p = context->trees;
1601 count = context->tree_count;
1602 rcu_read_lock();
1603 chunk = audit_tree_lookup(inode);
1604 rcu_read_unlock();
1605 if (!chunk)
1606 return;
1607 if (likely(put_tree_ref(context, chunk)))
1608 return;
1609 if (unlikely(!grow_tree_refs(context))) {
1610 printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
1611 audit_set_auditable(context);
1612 audit_put_chunk(chunk);
1613 unroll_tree_refs(context, p, count);
1614 return;
1615 }
1616 put_tree_ref(context, chunk);
1617 #endif
1618 }
1619
1620 static void handle_path(const struct dentry *dentry)
1621 {
1622 #ifdef CONFIG_AUDIT_TREE
1623 struct audit_context *context;
1624 struct audit_tree_refs *p;
1625 const struct dentry *d, *parent;
1626 struct audit_chunk *drop;
1627 unsigned long seq;
1628 int count;
1629
1630 context = current->audit_context;
1631 p = context->trees;
1632 count = context->tree_count;
1633 retry:
1634 drop = NULL;
1635 d = dentry;
1636 rcu_read_lock();
1637 seq = read_seqbegin(&rename_lock);
1638 for(;;) {
1639 struct inode *inode = d->d_inode;
1640 if (inode && unlikely(!list_empty(&inode->inotify_watches))) {
1641 struct audit_chunk *chunk;
1642 chunk = audit_tree_lookup(inode);
1643 if (chunk) {
1644 if (unlikely(!put_tree_ref(context, chunk))) {
1645 drop = chunk;
1646 break;
1647 }
1648 }
1649 }
1650 parent = d->d_parent;
1651 if (parent == d)
1652 break;
1653 d = parent;
1654 }
1655 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */
1656 rcu_read_unlock();
1657 if (!drop) {
1658 /* just a race with rename */
1659 unroll_tree_refs(context, p, count);
1660 goto retry;
1661 }
1662 audit_put_chunk(drop);
1663 if (grow_tree_refs(context)) {
1664 /* OK, got more space */
1665 unroll_tree_refs(context, p, count);
1666 goto retry;
1667 }
1668 /* too bad */
1669 printk(KERN_WARNING
1670 "out of memory, audit has lost a tree reference\n");
1671 unroll_tree_refs(context, p, count);
1672 audit_set_auditable(context);
1673 return;
1674 }
1675 rcu_read_unlock();
1676 #endif
1677 }
1678
1679 /**
1680 * audit_getname - add a name to the list
1681 * @name: name to add
1682 *
1683 * Add a name to the list of audit names for this context.
1684 * Called from fs/namei.c:getname().
1685 */
1686 void __audit_getname(const char *name)
1687 {
1688 struct audit_context *context = current->audit_context;
1689
1690 if (IS_ERR(name) || !name)
1691 return;
1692
1693 if (!context->in_syscall) {
1694 #if AUDIT_DEBUG == 2
1695 printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
1696 __FILE__, __LINE__, context->serial, name);
1697 dump_stack();
1698 #endif
1699 return;
1700 }
1701 BUG_ON(context->name_count >= AUDIT_NAMES);
1702 context->names[context->name_count].name = name;
1703 context->names[context->name_count].name_len = AUDIT_NAME_FULL;
1704 context->names[context->name_count].name_put = 1;
1705 context->names[context->name_count].ino = (unsigned long)-1;
1706 context->names[context->name_count].osid = 0;
1707 ++context->name_count;
1708 if (!context->pwd.dentry) {
1709 read_lock(&current->fs->lock);
1710 context->pwd = current->fs->pwd;
1711 path_get(&current->fs->pwd);
1712 read_unlock(&current->fs->lock);
1713 }
1714
1715 }
1716
1717 /* audit_putname - intercept a putname request
1718 * @name: name to intercept and delay for putname
1719 *
1720 * If we have stored the name from getname in the audit context,
1721 * then we delay the putname until syscall exit.
1722 * Called from include/linux/fs.h:putname().
1723 */
1724 void audit_putname(const char *name)
1725 {
1726 struct audit_context *context = current->audit_context;
1727
1728 BUG_ON(!context);
1729 if (!context->in_syscall) {
1730 #if AUDIT_DEBUG == 2
1731 printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n",
1732 __FILE__, __LINE__, context->serial, name);
1733 if (context->name_count) {
1734 int i;
1735 for (i = 0; i < context->name_count; i++)
1736 printk(KERN_ERR "name[%d] = %p = %s\n", i,
1737 context->names[i].name,
1738 context->names[i].name ?: "(null)");
1739 }
1740 #endif
1741 __putname(name);
1742 }
1743 #if AUDIT_DEBUG
1744 else {
1745 ++context->put_count;
1746 if (context->put_count > context->name_count) {
1747 printk(KERN_ERR "%s:%d(:%d): major=%d"
1748 " in_syscall=%d putname(%p) name_count=%d"
1749 " put_count=%d\n",
1750 __FILE__, __LINE__,
1751 context->serial, context->major,
1752 context->in_syscall, name, context->name_count,
1753 context->put_count);
1754 dump_stack();
1755 }
1756 }
1757 #endif
1758 }
1759
1760 static int audit_inc_name_count(struct audit_context *context,
1761 const struct inode *inode)
1762 {
1763 if (context->name_count >= AUDIT_NAMES) {
1764 if (inode)
1765 printk(KERN_DEBUG "name_count maxed, losing inode data: "
1766 "dev=%02x:%02x, inode=%lu\n",
1767 MAJOR(inode->i_sb->s_dev),
1768 MINOR(inode->i_sb->s_dev),
1769 inode->i_ino);
1770
1771 else
1772 printk(KERN_DEBUG "name_count maxed, losing inode data\n");
1773 return 1;
1774 }
1775 context->name_count++;
1776 #if AUDIT_DEBUG
1777 context->ino_count++;
1778 #endif
1779 return 0;
1780 }
1781
1782 /* Copy inode data into an audit_names. */
1783 static void audit_copy_inode(struct audit_names *name, const struct inode *inode)
1784 {
1785 name->ino = inode->i_ino;
1786 name->dev = inode->i_sb->s_dev;
1787 name->mode = inode->i_mode;
1788 name->uid = inode->i_uid;
1789 name->gid = inode->i_gid;
1790 name->rdev = inode->i_rdev;
1791 security_inode_getsecid(inode, &name->osid);
1792 }
1793
1794 /**
1795 * audit_inode - store the inode and device from a lookup
1796 * @name: name being audited
1797 * @dentry: dentry being audited
1798 *
1799 * Called from fs/namei.c:path_lookup().
1800 */
1801 void __audit_inode(const char *name, const struct dentry *dentry)
1802 {
1803 int idx;
1804 struct audit_context *context = current->audit_context;
1805 const struct inode *inode = dentry->d_inode;
1806
1807 if (!context->in_syscall)
1808 return;
1809 if (context->name_count
1810 && context->names[context->name_count-1].name
1811 && context->names[context->name_count-1].name == name)
1812 idx = context->name_count - 1;
1813 else if (context->name_count > 1
1814 && context->names[context->name_count-2].name
1815 && context->names[context->name_count-2].name == name)
1816 idx = context->name_count - 2;
1817 else {
1818 /* FIXME: how much do we care about inodes that have no
1819 * associated name? */
1820 if (audit_inc_name_count(context, inode))
1821 return;
1822 idx = context->name_count - 1;
1823 context->names[idx].name = NULL;
1824 }
1825 handle_path(dentry);
1826 audit_copy_inode(&context->names[idx], inode);
1827 }
1828
1829 /**
1830 * audit_inode_child - collect inode info for created/removed objects
1831 * @dname: inode's dentry name
1832 * @dentry: dentry being audited
1833 * @parent: inode of dentry parent
1834 *
1835 * For syscalls that create or remove filesystem objects, audit_inode
1836 * can only collect information for the filesystem object's parent.
1837 * This call updates the audit context with the child's information.
1838 * Syscalls that create a new filesystem object must be hooked after
1839 * the object is created. Syscalls that remove a filesystem object
1840 * must be hooked prior, in order to capture the target inode during
1841 * unsuccessful attempts.
1842 */
1843 void __audit_inode_child(const char *dname, const struct dentry *dentry,
1844 const struct inode *parent)
1845 {
1846 int idx;
1847 struct audit_context *context = current->audit_context;
1848 const char *found_parent = NULL, *found_child = NULL;
1849 const struct inode *inode = dentry->d_inode;
1850 int dirlen = 0;
1851
1852 if (!context->in_syscall)
1853 return;
1854
1855 if (inode)
1856 handle_one(inode);
1857 /* determine matching parent */
1858 if (!dname)
1859 goto add_names;
1860
1861 /* parent is more likely, look for it first */
1862 for (idx = 0; idx < context->name_count; idx++) {
1863 struct audit_names *n = &context->names[idx];
1864
1865 if (!n->name)
1866 continue;
1867
1868 if (n->ino == parent->i_ino &&
1869 !audit_compare_dname_path(dname, n->name, &dirlen)) {
1870 n->name_len = dirlen; /* update parent data in place */
1871 found_parent = n->name;
1872 goto add_names;
1873 }
1874 }
1875
1876 /* no matching parent, look for matching child */
1877 for (idx = 0; idx < context->name_count; idx++) {
1878 struct audit_names *n = &context->names[idx];
1879
1880 if (!n->name)
1881 continue;
1882
1883 /* strcmp() is the more likely scenario */
1884 if (!strcmp(dname, n->name) ||
1885 !audit_compare_dname_path(dname, n->name, &dirlen)) {
1886 if (inode)
1887 audit_copy_inode(n, inode);
1888 else
1889 n->ino = (unsigned long)-1;
1890 found_child = n->name;
1891 goto add_names;
1892 }
1893 }
1894
1895 add_names:
1896 if (!found_parent) {
1897 if (audit_inc_name_count(context, parent))
1898 return;
1899 idx = context->name_count - 1;
1900 context->names[idx].name = NULL;
1901 audit_copy_inode(&context->names[idx], parent);
1902 }
1903
1904 if (!found_child) {
1905 if (audit_inc_name_count(context, inode))
1906 return;
1907 idx = context->name_count - 1;
1908
1909 /* Re-use the name belonging to the slot for a matching parent
1910 * directory. All names for this context are relinquished in
1911 * audit_free_names() */
1912 if (found_parent) {
1913 context->names[idx].name = found_parent;
1914 context->names[idx].name_len = AUDIT_NAME_FULL;
1915 /* don't call __putname() */
1916 context->names[idx].name_put = 0;
1917 } else {
1918 context->names[idx].name = NULL;
1919 }
1920
1921 if (inode)
1922 audit_copy_inode(&context->names[idx], inode);
1923 else
1924 context->names[idx].ino = (unsigned long)-1;
1925 }
1926 }
1927 EXPORT_SYMBOL_GPL(__audit_inode_child);
1928
1929 /**
1930 * auditsc_get_stamp - get local copies of audit_context values
1931 * @ctx: audit_context for the task
1932 * @t: timespec to store time recorded in the audit_context
1933 * @serial: serial value that is recorded in the audit_context
1934 *
1935 * Also sets the context as auditable.
1936 */
1937 void auditsc_get_stamp(struct audit_context *ctx,
1938 struct timespec *t, unsigned int *serial)
1939 {
1940 if (!ctx->serial)
1941 ctx->serial = audit_serial();
1942 t->tv_sec = ctx->ctime.tv_sec;
1943 t->tv_nsec = ctx->ctime.tv_nsec;
1944 *serial = ctx->serial;
1945 ctx->auditable = 1;
1946 }
1947
1948 /* global counter which is incremented every time something logs in */
1949 static atomic_t session_id = ATOMIC_INIT(0);
1950
1951 /**
1952 * audit_set_loginuid - set a task's audit_context loginuid
1953 * @task: task whose audit context is being modified
1954 * @loginuid: loginuid value
1955 *
1956 * Returns 0.
1957 *
1958 * Called (set) from fs/proc/base.c::proc_loginuid_write().
1959 */
1960 int audit_set_loginuid(struct task_struct *task, uid_t loginuid)
1961 {
1962 unsigned int sessionid = atomic_inc_return(&session_id);
1963 struct audit_context *context = task->audit_context;
1964
1965 if (context && context->in_syscall) {
1966 struct audit_buffer *ab;
1967
1968 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
1969 if (ab) {
1970 audit_log_format(ab, "login pid=%d uid=%u "
1971 "old auid=%u new auid=%u"
1972 " old ses=%u new ses=%u",
1973 task->pid, task->uid,
1974 task->loginuid, loginuid,
1975 task->sessionid, sessionid);
1976 audit_log_end(ab);
1977 }
1978 }
1979 task->sessionid = sessionid;
1980 task->loginuid = loginuid;
1981 return 0;
1982 }
1983
1984 /**
1985 * __audit_mq_open - record audit data for a POSIX MQ open
1986 * @oflag: open flag
1987 * @mode: mode bits
1988 * @u_attr: queue attributes
1989 *
1990 * Returns 0 for success or NULL context or < 0 on error.
1991 */
1992 int __audit_mq_open(int oflag, mode_t mode, struct mq_attr __user *u_attr)
1993 {
1994 struct audit_aux_data_mq_open *ax;
1995 struct audit_context *context = current->audit_context;
1996
1997 if (!audit_enabled)
1998 return 0;
1999
2000 if (likely(!context))
2001 return 0;
2002
2003 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2004 if (!ax)
2005 return -ENOMEM;
2006
2007 if (u_attr != NULL) {
2008 if (copy_from_user(&ax->attr, u_attr, sizeof(ax->attr))) {
2009 kfree(ax);
2010 return -EFAULT;
2011 }
2012 } else
2013 memset(&ax->attr, 0, sizeof(ax->attr));
2014
2015 ax->oflag = oflag;
2016 ax->mode = mode;
2017
2018 ax->d.type = AUDIT_MQ_OPEN;
2019 ax->d.next = context->aux;
2020 context->aux = (void *)ax;
2021 return 0;
2022 }
2023
2024 /**
2025 * __audit_mq_timedsend - record audit data for a POSIX MQ timed send
2026 * @mqdes: MQ descriptor
2027 * @msg_len: Message length
2028 * @msg_prio: Message priority
2029 * @u_abs_timeout: Message timeout in absolute time
2030 *
2031 * Returns 0 for success or NULL context or < 0 on error.
2032 */
2033 int __audit_mq_timedsend(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2034 const struct timespec __user *u_abs_timeout)
2035 {
2036 struct audit_aux_data_mq_sendrecv *ax;
2037 struct audit_context *context = current->audit_context;
2038
2039 if (!audit_enabled)
2040 return 0;
2041
2042 if (likely(!context))
2043 return 0;
2044
2045 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2046 if (!ax)
2047 return -ENOMEM;
2048
2049 if (u_abs_timeout != NULL) {
2050 if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) {
2051 kfree(ax);
2052 return -EFAULT;
2053 }
2054 } else
2055 memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout));
2056
2057 ax->mqdes = mqdes;
2058 ax->msg_len = msg_len;
2059 ax->msg_prio = msg_prio;
2060
2061 ax->d.type = AUDIT_MQ_SENDRECV;
2062 ax->d.next = context->aux;
2063 context->aux = (void *)ax;
2064 return 0;
2065 }
2066
2067 /**
2068 * __audit_mq_timedreceive - record audit data for a POSIX MQ timed receive
2069 * @mqdes: MQ descriptor
2070 * @msg_len: Message length
2071 * @u_msg_prio: Message priority
2072 * @u_abs_timeout: Message timeout in absolute time
2073 *
2074 * Returns 0 for success or NULL context or < 0 on error.
2075 */
2076 int __audit_mq_timedreceive(mqd_t mqdes, size_t msg_len,
2077 unsigned int __user *u_msg_prio,
2078 const struct timespec __user *u_abs_timeout)
2079 {
2080 struct audit_aux_data_mq_sendrecv *ax;
2081 struct audit_context *context = current->audit_context;
2082
2083 if (!audit_enabled)
2084 return 0;
2085
2086 if (likely(!context))
2087 return 0;
2088
2089 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2090 if (!ax)
2091 return -ENOMEM;
2092
2093 if (u_msg_prio != NULL) {
2094 if (get_user(ax->msg_prio, u_msg_prio)) {
2095 kfree(ax);
2096 return -EFAULT;
2097 }
2098 } else
2099 ax->msg_prio = 0;
2100
2101 if (u_abs_timeout != NULL) {
2102 if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) {
2103 kfree(ax);
2104 return -EFAULT;
2105 }
2106 } else
2107 memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout));
2108
2109 ax->mqdes = mqdes;
2110 ax->msg_len = msg_len;
2111
2112 ax->d.type = AUDIT_MQ_SENDRECV;
2113 ax->d.next = context->aux;
2114 context->aux = (void *)ax;
2115 return 0;
2116 }
2117
2118 /**
2119 * __audit_mq_notify - record audit data for a POSIX MQ notify
2120 * @mqdes: MQ descriptor
2121 * @u_notification: Notification event
2122 *
2123 * Returns 0 for success or NULL context or < 0 on error.
2124 */
2125
2126 int __audit_mq_notify(mqd_t mqdes, const struct sigevent __user *u_notification)
2127 {
2128 struct audit_aux_data_mq_notify *ax;
2129 struct audit_context *context = current->audit_context;
2130
2131 if (!audit_enabled)
2132 return 0;
2133
2134 if (likely(!context))
2135 return 0;
2136
2137 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2138 if (!ax)
2139 return -ENOMEM;
2140
2141 if (u_notification != NULL) {
2142 if (copy_from_user(&ax->notification, u_notification, sizeof(ax->notification))) {
2143 kfree(ax);
2144 return -EFAULT;
2145 }
2146 } else
2147 memset(&ax->notification, 0, sizeof(ax->notification));
2148
2149 ax->mqdes = mqdes;
2150
2151 ax->d.type = AUDIT_MQ_NOTIFY;
2152 ax->d.next = context->aux;
2153 context->aux = (void *)ax;
2154 return 0;
2155 }
2156
2157 /**
2158 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2159 * @mqdes: MQ descriptor
2160 * @mqstat: MQ flags
2161 *
2162 * Returns 0 for success or NULL context or < 0 on error.
2163 */
2164 int __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2165 {
2166 struct audit_aux_data_mq_getsetattr *ax;
2167 struct audit_context *context = current->audit_context;
2168
2169 if (!audit_enabled)
2170 return 0;
2171
2172 if (likely(!context))
2173 return 0;
2174
2175 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2176 if (!ax)
2177 return -ENOMEM;
2178
2179 ax->mqdes = mqdes;
2180 ax->mqstat = *mqstat;
2181
2182 ax->d.type = AUDIT_MQ_GETSETATTR;
2183 ax->d.next = context->aux;
2184 context->aux = (void *)ax;
2185 return 0;
2186 }
2187
2188 /**
2189 * audit_ipc_obj - record audit data for ipc object
2190 * @ipcp: ipc permissions
2191 *
2192 * Returns 0 for success or NULL context or < 0 on error.
2193 */
2194 int __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2195 {
2196 struct audit_aux_data_ipcctl *ax;
2197 struct audit_context *context = current->audit_context;
2198
2199 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2200 if (!ax)
2201 return -ENOMEM;
2202
2203 ax->uid = ipcp->uid;
2204 ax->gid = ipcp->gid;
2205 ax->mode = ipcp->mode;
2206 security_ipc_getsecid(ipcp, &ax->osid);
2207 ax->d.type = AUDIT_IPC;
2208 ax->d.next = context->aux;
2209 context->aux = (void *)ax;
2210 return 0;
2211 }
2212
2213 /**
2214 * audit_ipc_set_perm - record audit data for new ipc permissions
2215 * @qbytes: msgq bytes
2216 * @uid: msgq user id
2217 * @gid: msgq group id
2218 * @mode: msgq mode (permissions)
2219 *
2220 * Returns 0 for success or NULL context or < 0 on error.
2221 */
2222 int __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode)
2223 {
2224 struct audit_aux_data_ipcctl *ax;
2225 struct audit_context *context = current->audit_context;
2226
2227 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2228 if (!ax)
2229 return -ENOMEM;
2230
2231 ax->qbytes = qbytes;
2232 ax->uid = uid;
2233 ax->gid = gid;
2234 ax->mode = mode;
2235
2236 ax->d.type = AUDIT_IPC_SET_PERM;
2237 ax->d.next = context->aux;
2238 context->aux = (void *)ax;
2239 return 0;
2240 }
2241
2242 int audit_bprm(struct linux_binprm *bprm)
2243 {
2244 struct audit_aux_data_execve *ax;
2245 struct audit_context *context = current->audit_context;
2246
2247 if (likely(!audit_enabled || !context || context->dummy))
2248 return 0;
2249
2250 ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2251 if (!ax)
2252 return -ENOMEM;
2253
2254 ax->argc = bprm->argc;
2255 ax->envc = bprm->envc;
2256 ax->mm = bprm->mm;
2257 ax->d.type = AUDIT_EXECVE;
2258 ax->d.next = context->aux;
2259 context->aux = (void *)ax;
2260 return 0;
2261 }
2262
2263
2264 /**
2265 * audit_socketcall - record audit data for sys_socketcall
2266 * @nargs: number of args
2267 * @args: args array
2268 *
2269 * Returns 0 for success or NULL context or < 0 on error.
2270 */
2271 int audit_socketcall(int nargs, unsigned long *args)
2272 {
2273 struct audit_aux_data_socketcall *ax;
2274 struct audit_context *context = current->audit_context;
2275
2276 if (likely(!context || context->dummy))
2277 return 0;
2278
2279 ax = kmalloc(sizeof(*ax) + nargs * sizeof(unsigned long), GFP_KERNEL);
2280 if (!ax)
2281 return -ENOMEM;
2282
2283 ax->nargs = nargs;
2284 memcpy(ax->args, args, nargs * sizeof(unsigned long));
2285
2286 ax->d.type = AUDIT_SOCKETCALL;
2287 ax->d.next = context->aux;
2288 context->aux = (void *)ax;
2289 return 0;
2290 }
2291
2292 /**
2293 * __audit_fd_pair - record audit data for pipe and socketpair
2294 * @fd1: the first file descriptor
2295 * @fd2: the second file descriptor
2296 *
2297 * Returns 0 for success or NULL context or < 0 on error.
2298 */
2299 int __audit_fd_pair(int fd1, int fd2)
2300 {
2301 struct audit_context *context = current->audit_context;
2302 struct audit_aux_data_fd_pair *ax;
2303
2304 if (likely(!context)) {
2305 return 0;
2306 }
2307
2308 ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2309 if (!ax) {
2310 return -ENOMEM;
2311 }
2312
2313 ax->fd[0] = fd1;
2314 ax->fd[1] = fd2;
2315
2316 ax->d.type = AUDIT_FD_PAIR;
2317 ax->d.next = context->aux;
2318 context->aux = (void *)ax;
2319 return 0;
2320 }
2321
2322 /**
2323 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2324 * @len: data length in user space
2325 * @a: data address in kernel space
2326 *
2327 * Returns 0 for success or NULL context or < 0 on error.
2328 */
2329 int audit_sockaddr(int len, void *a)
2330 {
2331 struct audit_aux_data_sockaddr *ax;
2332 struct audit_context *context = current->audit_context;
2333
2334 if (likely(!context || context->dummy))
2335 return 0;
2336
2337 ax = kmalloc(sizeof(*ax) + len, GFP_KERNEL);
2338 if (!ax)
2339 return -ENOMEM;
2340
2341 ax->len = len;
2342 memcpy(ax->a, a, len);
2343
2344 ax->d.type = AUDIT_SOCKADDR;
2345 ax->d.next = context->aux;
2346 context->aux = (void *)ax;
2347 return 0;
2348 }
2349
2350 void __audit_ptrace(struct task_struct *t)
2351 {
2352 struct audit_context *context = current->audit_context;
2353
2354 context->target_pid = t->pid;
2355 context->target_auid = audit_get_loginuid(t);
2356 context->target_uid = t->uid;
2357 context->target_sessionid = audit_get_sessionid(t);
2358 security_task_getsecid(t, &context->target_sid);
2359 memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
2360 }
2361
2362 /**
2363 * audit_signal_info - record signal info for shutting down audit subsystem
2364 * @sig: signal value
2365 * @t: task being signaled
2366 *
2367 * If the audit subsystem is being terminated, record the task (pid)
2368 * and uid that is doing that.
2369 */
2370 int __audit_signal_info(int sig, struct task_struct *t)
2371 {
2372 struct audit_aux_data_pids *axp;
2373 struct task_struct *tsk = current;
2374 struct audit_context *ctx = tsk->audit_context;
2375
2376 if (audit_pid && t->tgid == audit_pid) {
2377 if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1) {
2378 audit_sig_pid = tsk->pid;
2379 if (tsk->loginuid != -1)
2380 audit_sig_uid = tsk->loginuid;
2381 else
2382 audit_sig_uid = tsk->uid;
2383 security_task_getsecid(tsk, &audit_sig_sid);
2384 }
2385 if (!audit_signals || audit_dummy_context())
2386 return 0;
2387 }
2388
2389 /* optimize the common case by putting first signal recipient directly
2390 * in audit_context */
2391 if (!ctx->target_pid) {
2392 ctx->target_pid = t->tgid;
2393 ctx->target_auid = audit_get_loginuid(t);
2394 ctx->target_uid = t->uid;
2395 ctx->target_sessionid = audit_get_sessionid(t);
2396 security_task_getsecid(t, &ctx->target_sid);
2397 memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
2398 return 0;
2399 }
2400
2401 axp = (void *)ctx->aux_pids;
2402 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2403 axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2404 if (!axp)
2405 return -ENOMEM;
2406
2407 axp->d.type = AUDIT_OBJ_PID;
2408 axp->d.next = ctx->aux_pids;
2409 ctx->aux_pids = (void *)axp;
2410 }
2411 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2412
2413 axp->target_pid[axp->pid_count] = t->tgid;
2414 axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2415 axp->target_uid[axp->pid_count] = t->uid;
2416 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2417 security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2418 memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
2419 axp->pid_count++;
2420
2421 return 0;
2422 }
2423
2424 /**
2425 * audit_core_dumps - record information about processes that end abnormally
2426 * @signr: signal value
2427 *
2428 * If a process ends with a core dump, something fishy is going on and we
2429 * should record the event for investigation.
2430 */
2431 void audit_core_dumps(long signr)
2432 {
2433 struct audit_buffer *ab;
2434 u32 sid;
2435 uid_t auid = audit_get_loginuid(current);
2436 unsigned int sessionid = audit_get_sessionid(current);
2437
2438 if (!audit_enabled)
2439 return;
2440
2441 if (signr == SIGQUIT) /* don't care for those */
2442 return;
2443
2444 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2445 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2446 auid, current->uid, current->gid, sessionid);
2447 security_task_getsecid(current, &sid);
2448 if (sid) {
2449 char *ctx = NULL;
2450 u32 len;
2451
2452 if (security_secid_to_secctx(sid, &ctx, &len))
2453 audit_log_format(ab, " ssid=%u", sid);
2454 else {
2455 audit_log_format(ab, " subj=%s", ctx);
2456 security_release_secctx(ctx, len);
2457 }
2458 }
2459 audit_log_format(ab, " pid=%d comm=", current->pid);
2460 audit_log_untrustedstring(ab, current->comm);
2461 audit_log_format(ab, " sig=%ld", signr);
2462 audit_log_end(ab);
2463 }
A Kernel for the Dreambox dm7025.