audit: rework execve audit
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / kernel / auditsc.c
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 <asm/types.h>
49 #include <linux/fs.h>
50 #include <linux/namei.h>
51 #include <linux/mm.h>
52 #include <linux/module.h>
53 #include <linux/mount.h>
54 #include <linux/socket.h>
55 #include <linux/mqueue.h>
56 #include <linux/audit.h>
57 #include <linux/personality.h>
58 #include <linux/time.h>
59 #include <linux/netlink.h>
60 #include <linux/compiler.h>
61 #include <asm/unistd.h>
62 #include <linux/security.h>
63 #include <linux/list.h>
64 #include <linux/tty.h>
65 #include <linux/selinux.h>
66 #include <linux/binfmts.h>
67 #include <linux/highmem.h>
68 #include <linux/syscalls.h>
69
70 #include "audit.h"
71
72 extern struct list_head audit_filter_list[];
73
74 /* AUDIT_NAMES is the number of slots we reserve in the audit_context
75 * for saving names from getname(). */
76 #define AUDIT_NAMES 20
77
78 /* Indicates that audit should log the full pathname. */
79 #define AUDIT_NAME_FULL -1
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_path {
177 struct audit_aux_data d;
178 struct dentry *dentry;
179 struct vfsmount *mnt;
180 };
181
182 struct audit_aux_data_pids {
183 struct audit_aux_data d;
184 pid_t target_pid[AUDIT_AUX_PIDS];
185 u32 target_sid[AUDIT_AUX_PIDS];
186 int pid_count;
187 };
188
189 /* The per-task audit context. */
190 struct audit_context {
191 int dummy; /* must be the first element */
192 int in_syscall; /* 1 if task is in a syscall */
193 enum audit_state state;
194 unsigned int serial; /* serial number for record */
195 struct timespec ctime; /* time of syscall entry */
196 uid_t loginuid; /* login uid (identity) */
197 int major; /* syscall number */
198 unsigned long argv[4]; /* syscall arguments */
199 int return_valid; /* return code is valid */
200 long return_code;/* syscall return code */
201 int auditable; /* 1 if record should be written */
202 int name_count;
203 struct audit_names names[AUDIT_NAMES];
204 char * filterkey; /* key for rule that triggered record */
205 struct dentry * pwd;
206 struct vfsmount * pwdmnt;
207 struct audit_context *previous; /* For nested syscalls */
208 struct audit_aux_data *aux;
209 struct audit_aux_data *aux_pids;
210
211 /* Save things to print about task_struct */
212 pid_t pid, ppid;
213 uid_t uid, euid, suid, fsuid;
214 gid_t gid, egid, sgid, fsgid;
215 unsigned long personality;
216 int arch;
217
218 pid_t target_pid;
219 u32 target_sid;
220
221 #if AUDIT_DEBUG
222 int put_count;
223 int ino_count;
224 #endif
225 };
226
227 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
228 static inline int open_arg(int flags, int mask)
229 {
230 int n = ACC_MODE(flags);
231 if (flags & (O_TRUNC | O_CREAT))
232 n |= AUDIT_PERM_WRITE;
233 return n & mask;
234 }
235
236 static int audit_match_perm(struct audit_context *ctx, int mask)
237 {
238 unsigned n = ctx->major;
239 switch (audit_classify_syscall(ctx->arch, n)) {
240 case 0: /* native */
241 if ((mask & AUDIT_PERM_WRITE) &&
242 audit_match_class(AUDIT_CLASS_WRITE, n))
243 return 1;
244 if ((mask & AUDIT_PERM_READ) &&
245 audit_match_class(AUDIT_CLASS_READ, n))
246 return 1;
247 if ((mask & AUDIT_PERM_ATTR) &&
248 audit_match_class(AUDIT_CLASS_CHATTR, n))
249 return 1;
250 return 0;
251 case 1: /* 32bit on biarch */
252 if ((mask & AUDIT_PERM_WRITE) &&
253 audit_match_class(AUDIT_CLASS_WRITE_32, n))
254 return 1;
255 if ((mask & AUDIT_PERM_READ) &&
256 audit_match_class(AUDIT_CLASS_READ_32, n))
257 return 1;
258 if ((mask & AUDIT_PERM_ATTR) &&
259 audit_match_class(AUDIT_CLASS_CHATTR_32, n))
260 return 1;
261 return 0;
262 case 2: /* open */
263 return mask & ACC_MODE(ctx->argv[1]);
264 case 3: /* openat */
265 return mask & ACC_MODE(ctx->argv[2]);
266 case 4: /* socketcall */
267 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
268 case 5: /* execve */
269 return mask & AUDIT_PERM_EXEC;
270 default:
271 return 0;
272 }
273 }
274
275 /* Determine if any context name data matches a rule's watch data */
276 /* Compare a task_struct with an audit_rule. Return 1 on match, 0
277 * otherwise. */
278 static int audit_filter_rules(struct task_struct *tsk,
279 struct audit_krule *rule,
280 struct audit_context *ctx,
281 struct audit_names *name,
282 enum audit_state *state)
283 {
284 int i, j, need_sid = 1;
285 u32 sid;
286
287 for (i = 0; i < rule->field_count; i++) {
288 struct audit_field *f = &rule->fields[i];
289 int result = 0;
290
291 switch (f->type) {
292 case AUDIT_PID:
293 result = audit_comparator(tsk->pid, f->op, f->val);
294 break;
295 case AUDIT_PPID:
296 if (ctx) {
297 if (!ctx->ppid)
298 ctx->ppid = sys_getppid();
299 result = audit_comparator(ctx->ppid, f->op, f->val);
300 }
301 break;
302 case AUDIT_UID:
303 result = audit_comparator(tsk->uid, f->op, f->val);
304 break;
305 case AUDIT_EUID:
306 result = audit_comparator(tsk->euid, f->op, f->val);
307 break;
308 case AUDIT_SUID:
309 result = audit_comparator(tsk->suid, f->op, f->val);
310 break;
311 case AUDIT_FSUID:
312 result = audit_comparator(tsk->fsuid, f->op, f->val);
313 break;
314 case AUDIT_GID:
315 result = audit_comparator(tsk->gid, f->op, f->val);
316 break;
317 case AUDIT_EGID:
318 result = audit_comparator(tsk->egid, f->op, f->val);
319 break;
320 case AUDIT_SGID:
321 result = audit_comparator(tsk->sgid, f->op, f->val);
322 break;
323 case AUDIT_FSGID:
324 result = audit_comparator(tsk->fsgid, f->op, f->val);
325 break;
326 case AUDIT_PERS:
327 result = audit_comparator(tsk->personality, f->op, f->val);
328 break;
329 case AUDIT_ARCH:
330 if (ctx)
331 result = audit_comparator(ctx->arch, f->op, f->val);
332 break;
333
334 case AUDIT_EXIT:
335 if (ctx && ctx->return_valid)
336 result = audit_comparator(ctx->return_code, f->op, f->val);
337 break;
338 case AUDIT_SUCCESS:
339 if (ctx && ctx->return_valid) {
340 if (f->val)
341 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
342 else
343 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
344 }
345 break;
346 case AUDIT_DEVMAJOR:
347 if (name)
348 result = audit_comparator(MAJOR(name->dev),
349 f->op, f->val);
350 else if (ctx) {
351 for (j = 0; j < ctx->name_count; j++) {
352 if (audit_comparator(MAJOR(ctx->names[j].dev), f->op, f->val)) {
353 ++result;
354 break;
355 }
356 }
357 }
358 break;
359 case AUDIT_DEVMINOR:
360 if (name)
361 result = audit_comparator(MINOR(name->dev),
362 f->op, f->val);
363 else if (ctx) {
364 for (j = 0; j < ctx->name_count; j++) {
365 if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) {
366 ++result;
367 break;
368 }
369 }
370 }
371 break;
372 case AUDIT_INODE:
373 if (name)
374 result = (name->ino == f->val);
375 else if (ctx) {
376 for (j = 0; j < ctx->name_count; j++) {
377 if (audit_comparator(ctx->names[j].ino, f->op, f->val)) {
378 ++result;
379 break;
380 }
381 }
382 }
383 break;
384 case AUDIT_WATCH:
385 if (name && rule->watch->ino != (unsigned long)-1)
386 result = (name->dev == rule->watch->dev &&
387 name->ino == rule->watch->ino);
388 break;
389 case AUDIT_LOGINUID:
390 result = 0;
391 if (ctx)
392 result = audit_comparator(ctx->loginuid, f->op, f->val);
393 break;
394 case AUDIT_SUBJ_USER:
395 case AUDIT_SUBJ_ROLE:
396 case AUDIT_SUBJ_TYPE:
397 case AUDIT_SUBJ_SEN:
398 case AUDIT_SUBJ_CLR:
399 /* NOTE: this may return negative values indicating
400 a temporary error. We simply treat this as a
401 match for now to avoid losing information that
402 may be wanted. An error message will also be
403 logged upon error */
404 if (f->se_rule) {
405 if (need_sid) {
406 selinux_get_task_sid(tsk, &sid);
407 need_sid = 0;
408 }
409 result = selinux_audit_rule_match(sid, f->type,
410 f->op,
411 f->se_rule,
412 ctx);
413 }
414 break;
415 case AUDIT_OBJ_USER:
416 case AUDIT_OBJ_ROLE:
417 case AUDIT_OBJ_TYPE:
418 case AUDIT_OBJ_LEV_LOW:
419 case AUDIT_OBJ_LEV_HIGH:
420 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
421 also applies here */
422 if (f->se_rule) {
423 /* Find files that match */
424 if (name) {
425 result = selinux_audit_rule_match(
426 name->osid, f->type, f->op,
427 f->se_rule, ctx);
428 } else if (ctx) {
429 for (j = 0; j < ctx->name_count; j++) {
430 if (selinux_audit_rule_match(
431 ctx->names[j].osid,
432 f->type, f->op,
433 f->se_rule, ctx)) {
434 ++result;
435 break;
436 }
437 }
438 }
439 /* Find ipc objects that match */
440 if (ctx) {
441 struct audit_aux_data *aux;
442 for (aux = ctx->aux; aux;
443 aux = aux->next) {
444 if (aux->type == AUDIT_IPC) {
445 struct audit_aux_data_ipcctl *axi = (void *)aux;
446 if (selinux_audit_rule_match(axi->osid, f->type, f->op, f->se_rule, ctx)) {
447 ++result;
448 break;
449 }
450 }
451 }
452 }
453 }
454 break;
455 case AUDIT_ARG0:
456 case AUDIT_ARG1:
457 case AUDIT_ARG2:
458 case AUDIT_ARG3:
459 if (ctx)
460 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
461 break;
462 case AUDIT_FILTERKEY:
463 /* ignore this field for filtering */
464 result = 1;
465 break;
466 case AUDIT_PERM:
467 result = audit_match_perm(ctx, f->val);
468 break;
469 }
470
471 if (!result)
472 return 0;
473 }
474 if (rule->filterkey)
475 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
476 switch (rule->action) {
477 case AUDIT_NEVER: *state = AUDIT_DISABLED; break;
478 case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break;
479 }
480 return 1;
481 }
482
483 /* At process creation time, we can determine if system-call auditing is
484 * completely disabled for this task. Since we only have the task
485 * structure at this point, we can only check uid and gid.
486 */
487 static enum audit_state audit_filter_task(struct task_struct *tsk)
488 {
489 struct audit_entry *e;
490 enum audit_state state;
491
492 rcu_read_lock();
493 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
494 if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) {
495 rcu_read_unlock();
496 return state;
497 }
498 }
499 rcu_read_unlock();
500 return AUDIT_BUILD_CONTEXT;
501 }
502
503 /* At syscall entry and exit time, this filter is called if the
504 * audit_state is not low enough that auditing cannot take place, but is
505 * also not high enough that we already know we have to write an audit
506 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
507 */
508 static enum audit_state audit_filter_syscall(struct task_struct *tsk,
509 struct audit_context *ctx,
510 struct list_head *list)
511 {
512 struct audit_entry *e;
513 enum audit_state state;
514
515 if (audit_pid && tsk->tgid == audit_pid)
516 return AUDIT_DISABLED;
517
518 rcu_read_lock();
519 if (!list_empty(list)) {
520 int word = AUDIT_WORD(ctx->major);
521 int bit = AUDIT_BIT(ctx->major);
522
523 list_for_each_entry_rcu(e, list, list) {
524 if ((e->rule.mask[word] & bit) == bit &&
525 audit_filter_rules(tsk, &e->rule, ctx, NULL,
526 &state)) {
527 rcu_read_unlock();
528 return state;
529 }
530 }
531 }
532 rcu_read_unlock();
533 return AUDIT_BUILD_CONTEXT;
534 }
535
536 /* At syscall exit time, this filter is called if any audit_names[] have been
537 * collected during syscall processing. We only check rules in sublists at hash
538 * buckets applicable to the inode numbers in audit_names[].
539 * Regarding audit_state, same rules apply as for audit_filter_syscall().
540 */
541 enum audit_state audit_filter_inodes(struct task_struct *tsk,
542 struct audit_context *ctx)
543 {
544 int i;
545 struct audit_entry *e;
546 enum audit_state state;
547
548 if (audit_pid && tsk->tgid == audit_pid)
549 return AUDIT_DISABLED;
550
551 rcu_read_lock();
552 for (i = 0; i < ctx->name_count; i++) {
553 int word = AUDIT_WORD(ctx->major);
554 int bit = AUDIT_BIT(ctx->major);
555 struct audit_names *n = &ctx->names[i];
556 int h = audit_hash_ino((u32)n->ino);
557 struct list_head *list = &audit_inode_hash[h];
558
559 if (list_empty(list))
560 continue;
561
562 list_for_each_entry_rcu(e, list, list) {
563 if ((e->rule.mask[word] & bit) == bit &&
564 audit_filter_rules(tsk, &e->rule, ctx, n, &state)) {
565 rcu_read_unlock();
566 return state;
567 }
568 }
569 }
570 rcu_read_unlock();
571 return AUDIT_BUILD_CONTEXT;
572 }
573
574 void audit_set_auditable(struct audit_context *ctx)
575 {
576 ctx->auditable = 1;
577 }
578
579 static inline struct audit_context *audit_get_context(struct task_struct *tsk,
580 int return_valid,
581 int return_code)
582 {
583 struct audit_context *context = tsk->audit_context;
584
585 if (likely(!context))
586 return NULL;
587 context->return_valid = return_valid;
588 context->return_code = return_code;
589
590 if (context->in_syscall && !context->dummy && !context->auditable) {
591 enum audit_state state;
592
593 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
594 if (state == AUDIT_RECORD_CONTEXT) {
595 context->auditable = 1;
596 goto get_context;
597 }
598
599 state = audit_filter_inodes(tsk, context);
600 if (state == AUDIT_RECORD_CONTEXT)
601 context->auditable = 1;
602
603 }
604
605 get_context:
606
607 tsk->audit_context = NULL;
608 return context;
609 }
610
611 static inline void audit_free_names(struct audit_context *context)
612 {
613 int i;
614
615 #if AUDIT_DEBUG == 2
616 if (context->auditable
617 ||context->put_count + context->ino_count != context->name_count) {
618 printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
619 " name_count=%d put_count=%d"
620 " ino_count=%d [NOT freeing]\n",
621 __FILE__, __LINE__,
622 context->serial, context->major, context->in_syscall,
623 context->name_count, context->put_count,
624 context->ino_count);
625 for (i = 0; i < context->name_count; i++) {
626 printk(KERN_ERR "names[%d] = %p = %s\n", i,
627 context->names[i].name,
628 context->names[i].name ?: "(null)");
629 }
630 dump_stack();
631 return;
632 }
633 #endif
634 #if AUDIT_DEBUG
635 context->put_count = 0;
636 context->ino_count = 0;
637 #endif
638
639 for (i = 0; i < context->name_count; i++) {
640 if (context->names[i].name && context->names[i].name_put)
641 __putname(context->names[i].name);
642 }
643 context->name_count = 0;
644 if (context->pwd)
645 dput(context->pwd);
646 if (context->pwdmnt)
647 mntput(context->pwdmnt);
648 context->pwd = NULL;
649 context->pwdmnt = NULL;
650 }
651
652 static inline void audit_free_aux(struct audit_context *context)
653 {
654 struct audit_aux_data *aux;
655
656 while ((aux = context->aux)) {
657 if (aux->type == AUDIT_AVC_PATH) {
658 struct audit_aux_data_path *axi = (void *)aux;
659 dput(axi->dentry);
660 mntput(axi->mnt);
661 }
662
663 context->aux = aux->next;
664 kfree(aux);
665 }
666 while ((aux = context->aux_pids)) {
667 context->aux_pids = aux->next;
668 kfree(aux);
669 }
670 }
671
672 static inline void audit_zero_context(struct audit_context *context,
673 enum audit_state state)
674 {
675 uid_t loginuid = context->loginuid;
676
677 memset(context, 0, sizeof(*context));
678 context->state = state;
679 context->loginuid = loginuid;
680 }
681
682 static inline struct audit_context *audit_alloc_context(enum audit_state state)
683 {
684 struct audit_context *context;
685
686 if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
687 return NULL;
688 audit_zero_context(context, state);
689 return context;
690 }
691
692 /**
693 * audit_alloc - allocate an audit context block for a task
694 * @tsk: task
695 *
696 * Filter on the task information and allocate a per-task audit context
697 * if necessary. Doing so turns on system call auditing for the
698 * specified task. This is called from copy_process, so no lock is
699 * needed.
700 */
701 int audit_alloc(struct task_struct *tsk)
702 {
703 struct audit_context *context;
704 enum audit_state state;
705
706 if (likely(!audit_enabled))
707 return 0; /* Return if not auditing. */
708
709 state = audit_filter_task(tsk);
710 if (likely(state == AUDIT_DISABLED))
711 return 0;
712
713 if (!(context = audit_alloc_context(state))) {
714 audit_log_lost("out of memory in audit_alloc");
715 return -ENOMEM;
716 }
717
718 /* Preserve login uid */
719 context->loginuid = -1;
720 if (current->audit_context)
721 context->loginuid = current->audit_context->loginuid;
722
723 tsk->audit_context = context;
724 set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
725 return 0;
726 }
727
728 static inline void audit_free_context(struct audit_context *context)
729 {
730 struct audit_context *previous;
731 int count = 0;
732
733 do {
734 previous = context->previous;
735 if (previous || (count && count < 10)) {
736 ++count;
737 printk(KERN_ERR "audit(:%d): major=%d name_count=%d:"
738 " freeing multiple contexts (%d)\n",
739 context->serial, context->major,
740 context->name_count, count);
741 }
742 audit_free_names(context);
743 audit_free_aux(context);
744 kfree(context->filterkey);
745 kfree(context);
746 context = previous;
747 } while (context);
748 if (count >= 10)
749 printk(KERN_ERR "audit: freed %d contexts\n", count);
750 }
751
752 void audit_log_task_context(struct audit_buffer *ab)
753 {
754 char *ctx = NULL;
755 unsigned len;
756 int error;
757 u32 sid;
758
759 selinux_get_task_sid(current, &sid);
760 if (!sid)
761 return;
762
763 error = selinux_sid_to_string(sid, &ctx, &len);
764 if (error) {
765 if (error != -EINVAL)
766 goto error_path;
767 return;
768 }
769
770 audit_log_format(ab, " subj=%s", ctx);
771 kfree(ctx);
772 return;
773
774 error_path:
775 audit_panic("error in audit_log_task_context");
776 return;
777 }
778
779 EXPORT_SYMBOL(audit_log_task_context);
780
781 static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
782 {
783 char name[sizeof(tsk->comm)];
784 struct mm_struct *mm = tsk->mm;
785 struct vm_area_struct *vma;
786
787 /* tsk == current */
788
789 get_task_comm(name, tsk);
790 audit_log_format(ab, " comm=");
791 audit_log_untrustedstring(ab, name);
792
793 if (mm) {
794 down_read(&mm->mmap_sem);
795 vma = mm->mmap;
796 while (vma) {
797 if ((vma->vm_flags & VM_EXECUTABLE) &&
798 vma->vm_file) {
799 audit_log_d_path(ab, "exe=",
800 vma->vm_file->f_path.dentry,
801 vma->vm_file->f_path.mnt);
802 break;
803 }
804 vma = vma->vm_next;
805 }
806 up_read(&mm->mmap_sem);
807 }
808 audit_log_task_context(ab);
809 }
810
811 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
812 u32 sid)
813 {
814 struct audit_buffer *ab;
815 char *s = NULL;
816 u32 len;
817 int rc = 0;
818
819 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
820 if (!ab)
821 return 1;
822
823 if (selinux_sid_to_string(sid, &s, &len)) {
824 audit_log_format(ab, "opid=%d obj=(none)", pid);
825 rc = 1;
826 } else
827 audit_log_format(ab, "opid=%d obj=%s", pid, s);
828 audit_log_end(ab);
829 kfree(s);
830
831 return rc;
832 }
833
834 static void audit_log_execve_info(struct audit_buffer *ab,
835 struct audit_aux_data_execve *axi)
836 {
837 int i;
838 long len, ret;
839 const char __user *p = (const char __user *)axi->mm->arg_start;
840 char *buf;
841
842 if (axi->mm != current->mm)
843 return; /* execve failed, no additional info */
844
845 for (i = 0; i < axi->argc; i++, p += len) {
846 len = strnlen_user(p, MAX_ARG_PAGES*PAGE_SIZE);
847 /*
848 * We just created this mm, if we can't find the strings
849 * we just copied into it something is _very_ wrong. Similar
850 * for strings that are too long, we should not have created
851 * any.
852 */
853 if (!len || len > MAX_ARG_STRLEN) {
854 WARN_ON(1);
855 send_sig(SIGKILL, current, 0);
856 }
857
858 buf = kmalloc(len, GFP_KERNEL);
859 if (!buf) {
860 audit_panic("out of memory for argv string\n");
861 break;
862 }
863
864 ret = copy_from_user(buf, p, len);
865 /*
866 * There is no reason for this copy to be short. We just
867 * copied them here, and the mm hasn't been exposed to user-
868 * space yet.
869 */
870 if (!ret) {
871 WARN_ON(1);
872 send_sig(SIGKILL, current, 0);
873 }
874
875 audit_log_format(ab, "a%d=", i);
876 audit_log_untrustedstring(ab, buf);
877 audit_log_format(ab, "\n");
878
879 kfree(buf);
880 }
881 }
882
883 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
884 {
885 int i, call_panic = 0;
886 struct audit_buffer *ab;
887 struct audit_aux_data *aux;
888 const char *tty;
889
890 /* tsk == current */
891 context->pid = tsk->pid;
892 if (!context->ppid)
893 context->ppid = sys_getppid();
894 context->uid = tsk->uid;
895 context->gid = tsk->gid;
896 context->euid = tsk->euid;
897 context->suid = tsk->suid;
898 context->fsuid = tsk->fsuid;
899 context->egid = tsk->egid;
900 context->sgid = tsk->sgid;
901 context->fsgid = tsk->fsgid;
902 context->personality = tsk->personality;
903
904 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
905 if (!ab)
906 return; /* audit_panic has been called */
907 audit_log_format(ab, "arch=%x syscall=%d",
908 context->arch, context->major);
909 if (context->personality != PER_LINUX)
910 audit_log_format(ab, " per=%lx", context->personality);
911 if (context->return_valid)
912 audit_log_format(ab, " success=%s exit=%ld",
913 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
914 context->return_code);
915
916 mutex_lock(&tty_mutex);
917 read_lock(&tasklist_lock);
918 if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
919 tty = tsk->signal->tty->name;
920 else
921 tty = "(none)";
922 read_unlock(&tasklist_lock);
923 audit_log_format(ab,
924 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
925 " ppid=%d pid=%d auid=%u uid=%u gid=%u"
926 " euid=%u suid=%u fsuid=%u"
927 " egid=%u sgid=%u fsgid=%u tty=%s",
928 context->argv[0],
929 context->argv[1],
930 context->argv[2],
931 context->argv[3],
932 context->name_count,
933 context->ppid,
934 context->pid,
935 context->loginuid,
936 context->uid,
937 context->gid,
938 context->euid, context->suid, context->fsuid,
939 context->egid, context->sgid, context->fsgid, tty);
940
941 mutex_unlock(&tty_mutex);
942
943 audit_log_task_info(ab, tsk);
944 if (context->filterkey) {
945 audit_log_format(ab, " key=");
946 audit_log_untrustedstring(ab, context->filterkey);
947 } else
948 audit_log_format(ab, " key=(null)");
949 audit_log_end(ab);
950
951 for (aux = context->aux; aux; aux = aux->next) {
952
953 ab = audit_log_start(context, GFP_KERNEL, aux->type);
954 if (!ab)
955 continue; /* audit_panic has been called */
956
957 switch (aux->type) {
958 case AUDIT_MQ_OPEN: {
959 struct audit_aux_data_mq_open *axi = (void *)aux;
960 audit_log_format(ab,
961 "oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld "
962 "mq_msgsize=%ld mq_curmsgs=%ld",
963 axi->oflag, axi->mode, axi->attr.mq_flags,
964 axi->attr.mq_maxmsg, axi->attr.mq_msgsize,
965 axi->attr.mq_curmsgs);
966 break; }
967
968 case AUDIT_MQ_SENDRECV: {
969 struct audit_aux_data_mq_sendrecv *axi = (void *)aux;
970 audit_log_format(ab,
971 "mqdes=%d msg_len=%zd msg_prio=%u "
972 "abs_timeout_sec=%ld abs_timeout_nsec=%ld",
973 axi->mqdes, axi->msg_len, axi->msg_prio,
974 axi->abs_timeout.tv_sec, axi->abs_timeout.tv_nsec);
975 break; }
976
977 case AUDIT_MQ_NOTIFY: {
978 struct audit_aux_data_mq_notify *axi = (void *)aux;
979 audit_log_format(ab,
980 "mqdes=%d sigev_signo=%d",
981 axi->mqdes,
982 axi->notification.sigev_signo);
983 break; }
984
985 case AUDIT_MQ_GETSETATTR: {
986 struct audit_aux_data_mq_getsetattr *axi = (void *)aux;
987 audit_log_format(ab,
988 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
989 "mq_curmsgs=%ld ",
990 axi->mqdes,
991 axi->mqstat.mq_flags, axi->mqstat.mq_maxmsg,
992 axi->mqstat.mq_msgsize, axi->mqstat.mq_curmsgs);
993 break; }
994
995 case AUDIT_IPC: {
996 struct audit_aux_data_ipcctl *axi = (void *)aux;
997 audit_log_format(ab,
998 "ouid=%u ogid=%u mode=%x",
999 axi->uid, axi->gid, axi->mode);
1000 if (axi->osid != 0) {
1001 char *ctx = NULL;
1002 u32 len;
1003 if (selinux_sid_to_string(
1004 axi->osid, &ctx, &len)) {
1005 audit_log_format(ab, " osid=%u",
1006 axi->osid);
1007 call_panic = 1;
1008 } else
1009 audit_log_format(ab, " obj=%s", ctx);
1010 kfree(ctx);
1011 }
1012 break; }
1013
1014 case AUDIT_IPC_SET_PERM: {
1015 struct audit_aux_data_ipcctl *axi = (void *)aux;
1016 audit_log_format(ab,
1017 "qbytes=%lx ouid=%u ogid=%u mode=%x",
1018 axi->qbytes, axi->uid, axi->gid, axi->mode);
1019 break; }
1020
1021 case AUDIT_EXECVE: {
1022 struct audit_aux_data_execve *axi = (void *)aux;
1023 audit_log_execve_info(ab, axi);
1024 break; }
1025
1026 case AUDIT_SOCKETCALL: {
1027 int i;
1028 struct audit_aux_data_socketcall *axs = (void *)aux;
1029 audit_log_format(ab, "nargs=%d", axs->nargs);
1030 for (i=0; i<axs->nargs; i++)
1031 audit_log_format(ab, " a%d=%lx", i, axs->args[i]);
1032 break; }
1033
1034 case AUDIT_SOCKADDR: {
1035 struct audit_aux_data_sockaddr *axs = (void *)aux;
1036
1037 audit_log_format(ab, "saddr=");
1038 audit_log_hex(ab, axs->a, axs->len);
1039 break; }
1040
1041 case AUDIT_AVC_PATH: {
1042 struct audit_aux_data_path *axi = (void *)aux;
1043 audit_log_d_path(ab, "path=", axi->dentry, axi->mnt);
1044 break; }
1045
1046 case AUDIT_FD_PAIR: {
1047 struct audit_aux_data_fd_pair *axs = (void *)aux;
1048 audit_log_format(ab, "fd0=%d fd1=%d", axs->fd[0], axs->fd[1]);
1049 break; }
1050
1051 }
1052 audit_log_end(ab);
1053 }
1054
1055 for (aux = context->aux_pids; aux; aux = aux->next) {
1056 struct audit_aux_data_pids *axs = (void *)aux;
1057 int i;
1058
1059 for (i = 0; i < axs->pid_count; i++)
1060 if (audit_log_pid_context(context, axs->target_pid[i],
1061 axs->target_sid[i]))
1062 call_panic = 1;
1063 }
1064
1065 if (context->target_pid &&
1066 audit_log_pid_context(context, context->target_pid,
1067 context->target_sid))
1068 call_panic = 1;
1069
1070 if (context->pwd && context->pwdmnt) {
1071 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1072 if (ab) {
1073 audit_log_d_path(ab, "cwd=", context->pwd, context->pwdmnt);
1074 audit_log_end(ab);
1075 }
1076 }
1077 for (i = 0; i < context->name_count; i++) {
1078 struct audit_names *n = &context->names[i];
1079
1080 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1081 if (!ab)
1082 continue; /* audit_panic has been called */
1083
1084 audit_log_format(ab, "item=%d", i);
1085
1086 if (n->name) {
1087 switch(n->name_len) {
1088 case AUDIT_NAME_FULL:
1089 /* log the full path */
1090 audit_log_format(ab, " name=");
1091 audit_log_untrustedstring(ab, n->name);
1092 break;
1093 case 0:
1094 /* name was specified as a relative path and the
1095 * directory component is the cwd */
1096 audit_log_d_path(ab, " name=", context->pwd,
1097 context->pwdmnt);
1098 break;
1099 default:
1100 /* log the name's directory component */
1101 audit_log_format(ab, " name=");
1102 audit_log_n_untrustedstring(ab, n->name_len,
1103 n->name);
1104 }
1105 } else
1106 audit_log_format(ab, " name=(null)");
1107
1108 if (n->ino != (unsigned long)-1) {
1109 audit_log_format(ab, " inode=%lu"
1110 " dev=%02x:%02x mode=%#o"
1111 " ouid=%u ogid=%u rdev=%02x:%02x",
1112 n->ino,
1113 MAJOR(n->dev),
1114 MINOR(n->dev),
1115 n->mode,
1116 n->uid,
1117 n->gid,
1118 MAJOR(n->rdev),
1119 MINOR(n->rdev));
1120 }
1121 if (n->osid != 0) {
1122 char *ctx = NULL;
1123 u32 len;
1124 if (selinux_sid_to_string(
1125 n->osid, &ctx, &len)) {
1126 audit_log_format(ab, " osid=%u", n->osid);
1127 call_panic = 2;
1128 } else
1129 audit_log_format(ab, " obj=%s", ctx);
1130 kfree(ctx);
1131 }
1132
1133 audit_log_end(ab);
1134 }
1135 if (call_panic)
1136 audit_panic("error converting sid to string");
1137 }
1138
1139 /**
1140 * audit_free - free a per-task audit context
1141 * @tsk: task whose audit context block to free
1142 *
1143 * Called from copy_process and do_exit
1144 */
1145 void audit_free(struct task_struct *tsk)
1146 {
1147 struct audit_context *context;
1148
1149 context = audit_get_context(tsk, 0, 0);
1150 if (likely(!context))
1151 return;
1152
1153 /* Check for system calls that do not go through the exit
1154 * function (e.g., exit_group), then free context block.
1155 * We use GFP_ATOMIC here because we might be doing this
1156 * in the context of the idle thread */
1157 /* that can happen only if we are called from do_exit() */
1158 if (context->in_syscall && context->auditable)
1159 audit_log_exit(context, tsk);
1160
1161 audit_free_context(context);
1162 }
1163
1164 /**
1165 * audit_syscall_entry - fill in an audit record at syscall entry
1166 * @tsk: task being audited
1167 * @arch: architecture type
1168 * @major: major syscall type (function)
1169 * @a1: additional syscall register 1
1170 * @a2: additional syscall register 2
1171 * @a3: additional syscall register 3
1172 * @a4: additional syscall register 4
1173 *
1174 * Fill in audit context at syscall entry. This only happens if the
1175 * audit context was created when the task was created and the state or
1176 * filters demand the audit context be built. If the state from the
1177 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1178 * then the record will be written at syscall exit time (otherwise, it
1179 * will only be written if another part of the kernel requests that it
1180 * be written).
1181 */
1182 void audit_syscall_entry(int arch, int major,
1183 unsigned long a1, unsigned long a2,
1184 unsigned long a3, unsigned long a4)
1185 {
1186 struct task_struct *tsk = current;
1187 struct audit_context *context = tsk->audit_context;
1188 enum audit_state state;
1189
1190 BUG_ON(!context);
1191
1192 /*
1193 * This happens only on certain architectures that make system
1194 * calls in kernel_thread via the entry.S interface, instead of
1195 * with direct calls. (If you are porting to a new
1196 * architecture, hitting this condition can indicate that you
1197 * got the _exit/_leave calls backward in entry.S.)
1198 *
1199 * i386 no
1200 * x86_64 no
1201 * ppc64 yes (see arch/powerpc/platforms/iseries/misc.S)
1202 *
1203 * This also happens with vm86 emulation in a non-nested manner
1204 * (entries without exits), so this case must be caught.
1205 */
1206 if (context->in_syscall) {
1207 struct audit_context *newctx;
1208
1209 #if AUDIT_DEBUG
1210 printk(KERN_ERR
1211 "audit(:%d) pid=%d in syscall=%d;"
1212 " entering syscall=%d\n",
1213 context->serial, tsk->pid, context->major, major);
1214 #endif
1215 newctx = audit_alloc_context(context->state);
1216 if (newctx) {
1217 newctx->previous = context;
1218 context = newctx;
1219 tsk->audit_context = newctx;
1220 } else {
1221 /* If we can't alloc a new context, the best we
1222 * can do is to leak memory (any pending putname
1223 * will be lost). The only other alternative is
1224 * to abandon auditing. */
1225 audit_zero_context(context, context->state);
1226 }
1227 }
1228 BUG_ON(context->in_syscall || context->name_count);
1229
1230 if (!audit_enabled)
1231 return;
1232
1233 context->arch = arch;
1234 context->major = major;
1235 context->argv[0] = a1;
1236 context->argv[1] = a2;
1237 context->argv[2] = a3;
1238 context->argv[3] = a4;
1239
1240 state = context->state;
1241 context->dummy = !audit_n_rules;
1242 if (!context->dummy && (state == AUDIT_SETUP_CONTEXT || state == AUDIT_BUILD_CONTEXT))
1243 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1244 if (likely(state == AUDIT_DISABLED))
1245 return;
1246
1247 context->serial = 0;
1248 context->ctime = CURRENT_TIME;
1249 context->in_syscall = 1;
1250 context->auditable = !!(state == AUDIT_RECORD_CONTEXT);
1251 context->ppid = 0;
1252 }
1253
1254 /**
1255 * audit_syscall_exit - deallocate audit context after a system call
1256 * @tsk: task being audited
1257 * @valid: success/failure flag
1258 * @return_code: syscall return value
1259 *
1260 * Tear down after system call. If the audit context has been marked as
1261 * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1262 * filtering, or because some other part of the kernel write an audit
1263 * message), then write out the syscall information. In call cases,
1264 * free the names stored from getname().
1265 */
1266 void audit_syscall_exit(int valid, long return_code)
1267 {
1268 struct task_struct *tsk = current;
1269 struct audit_context *context;
1270
1271 context = audit_get_context(tsk, valid, return_code);
1272
1273 if (likely(!context))
1274 return;
1275
1276 if (context->in_syscall && context->auditable)
1277 audit_log_exit(context, tsk);
1278
1279 context->in_syscall = 0;
1280 context->auditable = 0;
1281
1282 if (context->previous) {
1283 struct audit_context *new_context = context->previous;
1284 context->previous = NULL;
1285 audit_free_context(context);
1286 tsk->audit_context = new_context;
1287 } else {
1288 audit_free_names(context);
1289 audit_free_aux(context);
1290 context->aux = NULL;
1291 context->aux_pids = NULL;
1292 context->target_pid = 0;
1293 context->target_sid = 0;
1294 kfree(context->filterkey);
1295 context->filterkey = NULL;
1296 tsk->audit_context = context;
1297 }
1298 }
1299
1300 /**
1301 * audit_getname - add a name to the list
1302 * @name: name to add
1303 *
1304 * Add a name to the list of audit names for this context.
1305 * Called from fs/namei.c:getname().
1306 */
1307 void __audit_getname(const char *name)
1308 {
1309 struct audit_context *context = current->audit_context;
1310
1311 if (IS_ERR(name) || !name)
1312 return;
1313
1314 if (!context->in_syscall) {
1315 #if AUDIT_DEBUG == 2
1316 printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
1317 __FILE__, __LINE__, context->serial, name);
1318 dump_stack();
1319 #endif
1320 return;
1321 }
1322 BUG_ON(context->name_count >= AUDIT_NAMES);
1323 context->names[context->name_count].name = name;
1324 context->names[context->name_count].name_len = AUDIT_NAME_FULL;
1325 context->names[context->name_count].name_put = 1;
1326 context->names[context->name_count].ino = (unsigned long)-1;
1327 context->names[context->name_count].osid = 0;
1328 ++context->name_count;
1329 if (!context->pwd) {
1330 read_lock(&current->fs->lock);
1331 context->pwd = dget(current->fs->pwd);
1332 context->pwdmnt = mntget(current->fs->pwdmnt);
1333 read_unlock(&current->fs->lock);
1334 }
1335
1336 }
1337
1338 /* audit_putname - intercept a putname request
1339 * @name: name to intercept and delay for putname
1340 *
1341 * If we have stored the name from getname in the audit context,
1342 * then we delay the putname until syscall exit.
1343 * Called from include/linux/fs.h:putname().
1344 */
1345 void audit_putname(const char *name)
1346 {
1347 struct audit_context *context = current->audit_context;
1348
1349 BUG_ON(!context);
1350 if (!context->in_syscall) {
1351 #if AUDIT_DEBUG == 2
1352 printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n",
1353 __FILE__, __LINE__, context->serial, name);
1354 if (context->name_count) {
1355 int i;
1356 for (i = 0; i < context->name_count; i++)
1357 printk(KERN_ERR "name[%d] = %p = %s\n", i,
1358 context->names[i].name,
1359 context->names[i].name ?: "(null)");
1360 }
1361 #endif
1362 __putname(name);
1363 }
1364 #if AUDIT_DEBUG
1365 else {
1366 ++context->put_count;
1367 if (context->put_count > context->name_count) {
1368 printk(KERN_ERR "%s:%d(:%d): major=%d"
1369 " in_syscall=%d putname(%p) name_count=%d"
1370 " put_count=%d\n",
1371 __FILE__, __LINE__,
1372 context->serial, context->major,
1373 context->in_syscall, name, context->name_count,
1374 context->put_count);
1375 dump_stack();
1376 }
1377 }
1378 #endif
1379 }
1380
1381 static int audit_inc_name_count(struct audit_context *context,
1382 const struct inode *inode)
1383 {
1384 if (context->name_count >= AUDIT_NAMES) {
1385 if (inode)
1386 printk(KERN_DEBUG "name_count maxed, losing inode data: "
1387 "dev=%02x:%02x, inode=%lu",
1388 MAJOR(inode->i_sb->s_dev),
1389 MINOR(inode->i_sb->s_dev),
1390 inode->i_ino);
1391
1392 else
1393 printk(KERN_DEBUG "name_count maxed, losing inode data");
1394 return 1;
1395 }
1396 context->name_count++;
1397 #if AUDIT_DEBUG
1398 context->ino_count++;
1399 #endif
1400 return 0;
1401 }
1402
1403 /* Copy inode data into an audit_names. */
1404 static void audit_copy_inode(struct audit_names *name, const struct inode *inode)
1405 {
1406 name->ino = inode->i_ino;
1407 name->dev = inode->i_sb->s_dev;
1408 name->mode = inode->i_mode;
1409 name->uid = inode->i_uid;
1410 name->gid = inode->i_gid;
1411 name->rdev = inode->i_rdev;
1412 selinux_get_inode_sid(inode, &name->osid);
1413 }
1414
1415 /**
1416 * audit_inode - store the inode and device from a lookup
1417 * @name: name being audited
1418 * @inode: inode being audited
1419 *
1420 * Called from fs/namei.c:path_lookup().
1421 */
1422 void __audit_inode(const char *name, const struct inode *inode)
1423 {
1424 int idx;
1425 struct audit_context *context = current->audit_context;
1426
1427 if (!context->in_syscall)
1428 return;
1429 if (context->name_count
1430 && context->names[context->name_count-1].name
1431 && context->names[context->name_count-1].name == name)
1432 idx = context->name_count - 1;
1433 else if (context->name_count > 1
1434 && context->names[context->name_count-2].name
1435 && context->names[context->name_count-2].name == name)
1436 idx = context->name_count - 2;
1437 else {
1438 /* FIXME: how much do we care about inodes that have no
1439 * associated name? */
1440 if (audit_inc_name_count(context, inode))
1441 return;
1442 idx = context->name_count - 1;
1443 context->names[idx].name = NULL;
1444 }
1445 audit_copy_inode(&context->names[idx], inode);
1446 }
1447
1448 /**
1449 * audit_inode_child - collect inode info for created/removed objects
1450 * @dname: inode's dentry name
1451 * @inode: inode being audited
1452 * @parent: inode of dentry parent
1453 *
1454 * For syscalls that create or remove filesystem objects, audit_inode
1455 * can only collect information for the filesystem object's parent.
1456 * This call updates the audit context with the child's information.
1457 * Syscalls that create a new filesystem object must be hooked after
1458 * the object is created. Syscalls that remove a filesystem object
1459 * must be hooked prior, in order to capture the target inode during
1460 * unsuccessful attempts.
1461 */
1462 void __audit_inode_child(const char *dname, const struct inode *inode,
1463 const struct inode *parent)
1464 {
1465 int idx;
1466 struct audit_context *context = current->audit_context;
1467 const char *found_parent = NULL, *found_child = NULL;
1468 int dirlen = 0;
1469
1470 if (!context->in_syscall)
1471 return;
1472
1473 /* determine matching parent */
1474 if (!dname)
1475 goto add_names;
1476
1477 /* parent is more likely, look for it first */
1478 for (idx = 0; idx < context->name_count; idx++) {
1479 struct audit_names *n = &context->names[idx];
1480
1481 if (!n->name)
1482 continue;
1483
1484 if (n->ino == parent->i_ino &&
1485 !audit_compare_dname_path(dname, n->name, &dirlen)) {
1486 n->name_len = dirlen; /* update parent data in place */
1487 found_parent = n->name;
1488 goto add_names;
1489 }
1490 }
1491
1492 /* no matching parent, look for matching child */
1493 for (idx = 0; idx < context->name_count; idx++) {
1494 struct audit_names *n = &context->names[idx];
1495
1496 if (!n->name)
1497 continue;
1498
1499 /* strcmp() is the more likely scenario */
1500 if (!strcmp(dname, n->name) ||
1501 !audit_compare_dname_path(dname, n->name, &dirlen)) {
1502 if (inode)
1503 audit_copy_inode(n, inode);
1504 else
1505 n->ino = (unsigned long)-1;
1506 found_child = n->name;
1507 goto add_names;
1508 }
1509 }
1510
1511 add_names:
1512 if (!found_parent) {
1513 if (audit_inc_name_count(context, parent))
1514 return;
1515 idx = context->name_count - 1;
1516 context->names[idx].name = NULL;
1517 audit_copy_inode(&context->names[idx], parent);
1518 }
1519
1520 if (!found_child) {
1521 if (audit_inc_name_count(context, inode))
1522 return;
1523 idx = context->name_count - 1;
1524
1525 /* Re-use the name belonging to the slot for a matching parent
1526 * directory. All names for this context are relinquished in
1527 * audit_free_names() */
1528 if (found_parent) {
1529 context->names[idx].name = found_parent;
1530 context->names[idx].name_len = AUDIT_NAME_FULL;
1531 /* don't call __putname() */
1532 context->names[idx].name_put = 0;
1533 } else {
1534 context->names[idx].name = NULL;
1535 }
1536
1537 if (inode)
1538 audit_copy_inode(&context->names[idx], inode);
1539 else
1540 context->names[idx].ino = (unsigned long)-1;
1541 }
1542 }
1543
1544 /**
1545 * auditsc_get_stamp - get local copies of audit_context values
1546 * @ctx: audit_context for the task
1547 * @t: timespec to store time recorded in the audit_context
1548 * @serial: serial value that is recorded in the audit_context
1549 *
1550 * Also sets the context as auditable.
1551 */
1552 void auditsc_get_stamp(struct audit_context *ctx,
1553 struct timespec *t, unsigned int *serial)
1554 {
1555 if (!ctx->serial)
1556 ctx->serial = audit_serial();
1557 t->tv_sec = ctx->ctime.tv_sec;
1558 t->tv_nsec = ctx->ctime.tv_nsec;
1559 *serial = ctx->serial;
1560 ctx->auditable = 1;
1561 }
1562
1563 /**
1564 * audit_set_loginuid - set a task's audit_context loginuid
1565 * @task: task whose audit context is being modified
1566 * @loginuid: loginuid value
1567 *
1568 * Returns 0.
1569 *
1570 * Called (set) from fs/proc/base.c::proc_loginuid_write().
1571 */
1572 int audit_set_loginuid(struct task_struct *task, uid_t loginuid)
1573 {
1574 struct audit_context *context = task->audit_context;
1575
1576 if (context) {
1577 /* Only log if audit is enabled */
1578 if (context->in_syscall) {
1579 struct audit_buffer *ab;
1580
1581 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
1582 if (ab) {
1583 audit_log_format(ab, "login pid=%d uid=%u "
1584 "old auid=%u new auid=%u",
1585 task->pid, task->uid,
1586 context->loginuid, loginuid);
1587 audit_log_end(ab);
1588 }
1589 }
1590 context->loginuid = loginuid;
1591 }
1592 return 0;
1593 }
1594
1595 /**
1596 * audit_get_loginuid - get the loginuid for an audit_context
1597 * @ctx: the audit_context
1598 *
1599 * Returns the context's loginuid or -1 if @ctx is NULL.
1600 */
1601 uid_t audit_get_loginuid(struct audit_context *ctx)
1602 {
1603 return ctx ? ctx->loginuid : -1;
1604 }
1605
1606 EXPORT_SYMBOL(audit_get_loginuid);
1607
1608 /**
1609 * __audit_mq_open - record audit data for a POSIX MQ open
1610 * @oflag: open flag
1611 * @mode: mode bits
1612 * @u_attr: queue attributes
1613 *
1614 * Returns 0 for success or NULL context or < 0 on error.
1615 */
1616 int __audit_mq_open(int oflag, mode_t mode, struct mq_attr __user *u_attr)
1617 {
1618 struct audit_aux_data_mq_open *ax;
1619 struct audit_context *context = current->audit_context;
1620
1621 if (!audit_enabled)
1622 return 0;
1623
1624 if (likely(!context))
1625 return 0;
1626
1627 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1628 if (!ax)
1629 return -ENOMEM;
1630
1631 if (u_attr != NULL) {
1632 if (copy_from_user(&ax->attr, u_attr, sizeof(ax->attr))) {
1633 kfree(ax);
1634 return -EFAULT;
1635 }
1636 } else
1637 memset(&ax->attr, 0, sizeof(ax->attr));
1638
1639 ax->oflag = oflag;
1640 ax->mode = mode;
1641
1642 ax->d.type = AUDIT_MQ_OPEN;
1643 ax->d.next = context->aux;
1644 context->aux = (void *)ax;
1645 return 0;
1646 }
1647
1648 /**
1649 * __audit_mq_timedsend - record audit data for a POSIX MQ timed send
1650 * @mqdes: MQ descriptor
1651 * @msg_len: Message length
1652 * @msg_prio: Message priority
1653 * @u_abs_timeout: Message timeout in absolute time
1654 *
1655 * Returns 0 for success or NULL context or < 0 on error.
1656 */
1657 int __audit_mq_timedsend(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
1658 const struct timespec __user *u_abs_timeout)
1659 {
1660 struct audit_aux_data_mq_sendrecv *ax;
1661 struct audit_context *context = current->audit_context;
1662
1663 if (!audit_enabled)
1664 return 0;
1665
1666 if (likely(!context))
1667 return 0;
1668
1669 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1670 if (!ax)
1671 return -ENOMEM;
1672
1673 if (u_abs_timeout != NULL) {
1674 if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) {
1675 kfree(ax);
1676 return -EFAULT;
1677 }
1678 } else
1679 memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout));
1680
1681 ax->mqdes = mqdes;
1682 ax->msg_len = msg_len;
1683 ax->msg_prio = msg_prio;
1684
1685 ax->d.type = AUDIT_MQ_SENDRECV;
1686 ax->d.next = context->aux;
1687 context->aux = (void *)ax;
1688 return 0;
1689 }
1690
1691 /**
1692 * __audit_mq_timedreceive - record audit data for a POSIX MQ timed receive
1693 * @mqdes: MQ descriptor
1694 * @msg_len: Message length
1695 * @u_msg_prio: Message priority
1696 * @u_abs_timeout: Message timeout in absolute time
1697 *
1698 * Returns 0 for success or NULL context or < 0 on error.
1699 */
1700 int __audit_mq_timedreceive(mqd_t mqdes, size_t msg_len,
1701 unsigned int __user *u_msg_prio,
1702 const struct timespec __user *u_abs_timeout)
1703 {
1704 struct audit_aux_data_mq_sendrecv *ax;
1705 struct audit_context *context = current->audit_context;
1706
1707 if (!audit_enabled)
1708 return 0;
1709
1710 if (likely(!context))
1711 return 0;
1712
1713 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1714 if (!ax)
1715 return -ENOMEM;
1716
1717 if (u_msg_prio != NULL) {
1718 if (get_user(ax->msg_prio, u_msg_prio)) {
1719 kfree(ax);
1720 return -EFAULT;
1721 }
1722 } else
1723 ax->msg_prio = 0;
1724
1725 if (u_abs_timeout != NULL) {
1726 if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) {
1727 kfree(ax);
1728 return -EFAULT;
1729 }
1730 } else
1731 memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout));
1732
1733 ax->mqdes = mqdes;
1734 ax->msg_len = msg_len;
1735
1736 ax->d.type = AUDIT_MQ_SENDRECV;
1737 ax->d.next = context->aux;
1738 context->aux = (void *)ax;
1739 return 0;
1740 }
1741
1742 /**
1743 * __audit_mq_notify - record audit data for a POSIX MQ notify
1744 * @mqdes: MQ descriptor
1745 * @u_notification: Notification event
1746 *
1747 * Returns 0 for success or NULL context or < 0 on error.
1748 */
1749
1750 int __audit_mq_notify(mqd_t mqdes, const struct sigevent __user *u_notification)
1751 {
1752 struct audit_aux_data_mq_notify *ax;
1753 struct audit_context *context = current->audit_context;
1754
1755 if (!audit_enabled)
1756 return 0;
1757
1758 if (likely(!context))
1759 return 0;
1760
1761 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1762 if (!ax)
1763 return -ENOMEM;
1764
1765 if (u_notification != NULL) {
1766 if (copy_from_user(&ax->notification, u_notification, sizeof(ax->notification))) {
1767 kfree(ax);
1768 return -EFAULT;
1769 }
1770 } else
1771 memset(&ax->notification, 0, sizeof(ax->notification));
1772
1773 ax->mqdes = mqdes;
1774
1775 ax->d.type = AUDIT_MQ_NOTIFY;
1776 ax->d.next = context->aux;
1777 context->aux = (void *)ax;
1778 return 0;
1779 }
1780
1781 /**
1782 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
1783 * @mqdes: MQ descriptor
1784 * @mqstat: MQ flags
1785 *
1786 * Returns 0 for success or NULL context or < 0 on error.
1787 */
1788 int __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
1789 {
1790 struct audit_aux_data_mq_getsetattr *ax;
1791 struct audit_context *context = current->audit_context;
1792
1793 if (!audit_enabled)
1794 return 0;
1795
1796 if (likely(!context))
1797 return 0;
1798
1799 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1800 if (!ax)
1801 return -ENOMEM;
1802
1803 ax->mqdes = mqdes;
1804 ax->mqstat = *mqstat;
1805
1806 ax->d.type = AUDIT_MQ_GETSETATTR;
1807 ax->d.next = context->aux;
1808 context->aux = (void *)ax;
1809 return 0;
1810 }
1811
1812 /**
1813 * audit_ipc_obj - record audit data for ipc object
1814 * @ipcp: ipc permissions
1815 *
1816 * Returns 0 for success or NULL context or < 0 on error.
1817 */
1818 int __audit_ipc_obj(struct kern_ipc_perm *ipcp)
1819 {
1820 struct audit_aux_data_ipcctl *ax;
1821 struct audit_context *context = current->audit_context;
1822
1823 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1824 if (!ax)
1825 return -ENOMEM;
1826
1827 ax->uid = ipcp->uid;
1828 ax->gid = ipcp->gid;
1829 ax->mode = ipcp->mode;
1830 selinux_get_ipc_sid(ipcp, &ax->osid);
1831
1832 ax->d.type = AUDIT_IPC;
1833 ax->d.next = context->aux;
1834 context->aux = (void *)ax;
1835 return 0;
1836 }
1837
1838 /**
1839 * audit_ipc_set_perm - record audit data for new ipc permissions
1840 * @qbytes: msgq bytes
1841 * @uid: msgq user id
1842 * @gid: msgq group id
1843 * @mode: msgq mode (permissions)
1844 *
1845 * Returns 0 for success or NULL context or < 0 on error.
1846 */
1847 int __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode)
1848 {
1849 struct audit_aux_data_ipcctl *ax;
1850 struct audit_context *context = current->audit_context;
1851
1852 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1853 if (!ax)
1854 return -ENOMEM;
1855
1856 ax->qbytes = qbytes;
1857 ax->uid = uid;
1858 ax->gid = gid;
1859 ax->mode = mode;
1860
1861 ax->d.type = AUDIT_IPC_SET_PERM;
1862 ax->d.next = context->aux;
1863 context->aux = (void *)ax;
1864 return 0;
1865 }
1866
1867 int audit_argv_kb = 32;
1868
1869 int audit_bprm(struct linux_binprm *bprm)
1870 {
1871 struct audit_aux_data_execve *ax;
1872 struct audit_context *context = current->audit_context;
1873
1874 if (likely(!audit_enabled || !context || context->dummy))
1875 return 0;
1876
1877 /*
1878 * Even though the stack code doesn't limit the arg+env size any more,
1879 * the audit code requires that _all_ arguments be logged in a single
1880 * netlink skb. Hence cap it :-(
1881 */
1882 if (bprm->argv_len > (audit_argv_kb << 10))
1883 return -E2BIG;
1884
1885 ax = kmalloc(sizeof(*ax), GFP_KERNEL);
1886 if (!ax)
1887 return -ENOMEM;
1888
1889 ax->argc = bprm->argc;
1890 ax->envc = bprm->envc;
1891 ax->mm = bprm->mm;
1892 ax->d.type = AUDIT_EXECVE;
1893 ax->d.next = context->aux;
1894 context->aux = (void *)ax;
1895 return 0;
1896 }
1897
1898
1899 /**
1900 * audit_socketcall - record audit data for sys_socketcall
1901 * @nargs: number of args
1902 * @args: args array
1903 *
1904 * Returns 0 for success or NULL context or < 0 on error.
1905 */
1906 int audit_socketcall(int nargs, unsigned long *args)
1907 {
1908 struct audit_aux_data_socketcall *ax;
1909 struct audit_context *context = current->audit_context;
1910
1911 if (likely(!context || context->dummy))
1912 return 0;
1913
1914 ax = kmalloc(sizeof(*ax) + nargs * sizeof(unsigned long), GFP_KERNEL);
1915 if (!ax)
1916 return -ENOMEM;
1917
1918 ax->nargs = nargs;
1919 memcpy(ax->args, args, nargs * sizeof(unsigned long));
1920
1921 ax->d.type = AUDIT_SOCKETCALL;
1922 ax->d.next = context->aux;
1923 context->aux = (void *)ax;
1924 return 0;
1925 }
1926
1927 /**
1928 * __audit_fd_pair - record audit data for pipe and socketpair
1929 * @fd1: the first file descriptor
1930 * @fd2: the second file descriptor
1931 *
1932 * Returns 0 for success or NULL context or < 0 on error.
1933 */
1934 int __audit_fd_pair(int fd1, int fd2)
1935 {
1936 struct audit_context *context = current->audit_context;
1937 struct audit_aux_data_fd_pair *ax;
1938
1939 if (likely(!context)) {
1940 return 0;
1941 }
1942
1943 ax = kmalloc(sizeof(*ax), GFP_KERNEL);
1944 if (!ax) {
1945 return -ENOMEM;
1946 }
1947
1948 ax->fd[0] = fd1;
1949 ax->fd[1] = fd2;
1950
1951 ax->d.type = AUDIT_FD_PAIR;
1952 ax->d.next = context->aux;
1953 context->aux = (void *)ax;
1954 return 0;
1955 }
1956
1957 /**
1958 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
1959 * @len: data length in user space
1960 * @a: data address in kernel space
1961 *
1962 * Returns 0 for success or NULL context or < 0 on error.
1963 */
1964 int audit_sockaddr(int len, void *a)
1965 {
1966 struct audit_aux_data_sockaddr *ax;
1967 struct audit_context *context = current->audit_context;
1968
1969 if (likely(!context || context->dummy))
1970 return 0;
1971
1972 ax = kmalloc(sizeof(*ax) + len, GFP_KERNEL);
1973 if (!ax)
1974 return -ENOMEM;
1975
1976 ax->len = len;
1977 memcpy(ax->a, a, len);
1978
1979 ax->d.type = AUDIT_SOCKADDR;
1980 ax->d.next = context->aux;
1981 context->aux = (void *)ax;
1982 return 0;
1983 }
1984
1985 void __audit_ptrace(struct task_struct *t)
1986 {
1987 struct audit_context *context = current->audit_context;
1988
1989 context->target_pid = t->pid;
1990 selinux_get_task_sid(t, &context->target_sid);
1991 }
1992
1993 /**
1994 * audit_avc_path - record the granting or denial of permissions
1995 * @dentry: dentry to record
1996 * @mnt: mnt to record
1997 *
1998 * Returns 0 for success or NULL context or < 0 on error.
1999 *
2000 * Called from security/selinux/avc.c::avc_audit()
2001 */
2002 int audit_avc_path(struct dentry *dentry, struct vfsmount *mnt)
2003 {
2004 struct audit_aux_data_path *ax;
2005 struct audit_context *context = current->audit_context;
2006
2007 if (likely(!context))
2008 return 0;
2009
2010 ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2011 if (!ax)
2012 return -ENOMEM;
2013
2014 ax->dentry = dget(dentry);
2015 ax->mnt = mntget(mnt);
2016
2017 ax->d.type = AUDIT_AVC_PATH;
2018 ax->d.next = context->aux;
2019 context->aux = (void *)ax;
2020 return 0;
2021 }
2022
2023 /**
2024 * audit_signal_info - record signal info for shutting down audit subsystem
2025 * @sig: signal value
2026 * @t: task being signaled
2027 *
2028 * If the audit subsystem is being terminated, record the task (pid)
2029 * and uid that is doing that.
2030 */
2031 int __audit_signal_info(int sig, struct task_struct *t)
2032 {
2033 struct audit_aux_data_pids *axp;
2034 struct task_struct *tsk = current;
2035 struct audit_context *ctx = tsk->audit_context;
2036 extern pid_t audit_sig_pid;
2037 extern uid_t audit_sig_uid;
2038 extern u32 audit_sig_sid;
2039
2040 if (audit_pid && t->tgid == audit_pid &&
2041 (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1)) {
2042 audit_sig_pid = tsk->pid;
2043 if (ctx)
2044 audit_sig_uid = ctx->loginuid;
2045 else
2046 audit_sig_uid = tsk->uid;
2047 selinux_get_task_sid(tsk, &audit_sig_sid);
2048 }
2049
2050 if (!audit_signals) /* audit_context checked in wrapper */
2051 return 0;
2052
2053 /* optimize the common case by putting first signal recipient directly
2054 * in audit_context */
2055 if (!ctx->target_pid) {
2056 ctx->target_pid = t->tgid;
2057 selinux_get_task_sid(t, &ctx->target_sid);
2058 return 0;
2059 }
2060
2061 axp = (void *)ctx->aux_pids;
2062 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2063 axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2064 if (!axp)
2065 return -ENOMEM;
2066
2067 axp->d.type = AUDIT_OBJ_PID;
2068 axp->d.next = ctx->aux_pids;
2069 ctx->aux_pids = (void *)axp;
2070 }
2071 BUG_ON(axp->pid_count > AUDIT_AUX_PIDS);
2072
2073 axp->target_pid[axp->pid_count] = t->tgid;
2074 selinux_get_task_sid(t, &axp->target_sid[axp->pid_count]);
2075 axp->pid_count++;
2076
2077 return 0;
2078 }
2079
2080 /**
2081 * audit_core_dumps - record information about processes that end abnormally
2082 * @signr: signal value
2083 *
2084 * If a process ends with a core dump, something fishy is going on and we
2085 * should record the event for investigation.
2086 */
2087 void audit_core_dumps(long signr)
2088 {
2089 struct audit_buffer *ab;
2090 u32 sid;
2091
2092 if (!audit_enabled)
2093 return;
2094
2095 if (signr == SIGQUIT) /* don't care for those */
2096 return;
2097
2098 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2099 audit_log_format(ab, "auid=%u uid=%u gid=%u",
2100 audit_get_loginuid(current->audit_context),
2101 current->uid, current->gid);
2102 selinux_get_task_sid(current, &sid);
2103 if (sid) {
2104 char *ctx = NULL;
2105 u32 len;
2106
2107 if (selinux_sid_to_string(sid, &ctx, &len))
2108 audit_log_format(ab, " ssid=%u", sid);
2109 else
2110 audit_log_format(ab, " subj=%s", ctx);
2111 kfree(ctx);
2112 }
2113 audit_log_format(ab, " pid=%d comm=", current->pid);
2114 audit_log_untrustedstring(ab, current->comm);
2115 audit_log_format(ab, " sig=%ld", signr);
2116 audit_log_end(ab);
2117 }