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 #include <linux/capability.h>
69
70 #include "audit.h"
71
72 /* AUDIT_NAMES is the number of slots we reserve in the audit_context
73 * for saving names from getname(). */
74 #define AUDIT_NAMES 20
75
76 /* Indicates that audit should log the full pathname. */
77 #define AUDIT_NAME_FULL -1
78
79 /* no execve audit message should be longer than this (userspace limits) */
80 #define MAX_EXECVE_AUDIT_LEN 7500
81
82 /* number of audit rules */
83 int audit_n_rules;
84
85 /* determines whether we collect data for signals sent */
86 int audit_signals;
87
88 struct audit_cap_data {
89 kernel_cap_t permitted;
90 kernel_cap_t inheritable;
91 union {
92 unsigned int fE; /* effective bit of a file capability */
93 kernel_cap_t effective; /* effective set of a process */
94 };
95 };
96
97 /* When fs/namei.c:getname() is called, we store the pointer in name and
98 * we don't let putname() free it (instead we free all of the saved
99 * pointers at syscall exit time).
100 *
101 * Further, in fs/namei.c:path_lookup() we store the inode and device. */
102 struct audit_names {
103 const char *name;
104 int name_len; /* number of name's characters to log */
105 unsigned name_put; /* call __putname() for this name */
106 unsigned long ino;
107 dev_t dev;
108 umode_t mode;
109 uid_t uid;
110 gid_t gid;
111 dev_t rdev;
112 u32 osid;
113 struct audit_cap_data fcap;
114 unsigned int fcap_ver;
115 };
116
117 struct audit_aux_data {
118 struct audit_aux_data *next;
119 int type;
120 };
121
122 #define AUDIT_AUX_IPCPERM 0
123
124 /* Number of target pids per aux struct. */
125 #define AUDIT_AUX_PIDS 16
126
127 struct audit_aux_data_execve {
128 struct audit_aux_data d;
129 int argc;
130 int envc;
131 struct mm_struct *mm;
132 };
133
134 struct audit_aux_data_pids {
135 struct audit_aux_data d;
136 pid_t target_pid[AUDIT_AUX_PIDS];
137 uid_t target_auid[AUDIT_AUX_PIDS];
138 uid_t target_uid[AUDIT_AUX_PIDS];
139 unsigned int target_sessionid[AUDIT_AUX_PIDS];
140 u32 target_sid[AUDIT_AUX_PIDS];
141 char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
142 int pid_count;
143 };
144
145 struct audit_aux_data_bprm_fcaps {
146 struct audit_aux_data d;
147 struct audit_cap_data fcap;
148 unsigned int fcap_ver;
149 struct audit_cap_data old_pcap;
150 struct audit_cap_data new_pcap;
151 };
152
153 struct audit_aux_data_capset {
154 struct audit_aux_data d;
155 pid_t pid;
156 struct audit_cap_data cap;
157 };
158
159 struct audit_tree_refs {
160 struct audit_tree_refs *next;
161 struct audit_chunk *c[31];
162 };
163
164 /* The per-task audit context. */
165 struct audit_context {
166 int dummy; /* must be the first element */
167 int in_syscall; /* 1 if task is in a syscall */
168 enum audit_state state, current_state;
169 unsigned int serial; /* serial number for record */
170 struct timespec ctime; /* time of syscall entry */
171 int major; /* syscall number */
172 unsigned long argv[4]; /* syscall arguments */
173 int return_valid; /* return code is valid */
174 long return_code;/* syscall return code */
175 u64 prio;
176 int name_count;
177 struct audit_names names[AUDIT_NAMES];
178 char * filterkey; /* key for rule that triggered record */
179 struct path pwd;
180 struct audit_context *previous; /* For nested syscalls */
181 struct audit_aux_data *aux;
182 struct audit_aux_data *aux_pids;
183 struct sockaddr_storage *sockaddr;
184 size_t sockaddr_len;
185 /* Save things to print about task_struct */
186 pid_t pid, ppid;
187 uid_t uid, euid, suid, fsuid;
188 gid_t gid, egid, sgid, fsgid;
189 unsigned long personality;
190 int arch;
191
192 pid_t target_pid;
193 uid_t target_auid;
194 uid_t target_uid;
195 unsigned int target_sessionid;
196 u32 target_sid;
197 char target_comm[TASK_COMM_LEN];
198
199 struct audit_tree_refs *trees, *first_trees;
200 int tree_count;
201
202 int type;
203 union {
204 struct {
205 int nargs;
206 long args[6];
207 } socketcall;
208 struct {
209 uid_t uid;
210 gid_t gid;
211 mode_t mode;
212 u32 osid;
213 int has_perm;
214 uid_t perm_uid;
215 gid_t perm_gid;
216 mode_t perm_mode;
217 unsigned long qbytes;
218 } ipc;
219 struct {
220 mqd_t mqdes;
221 struct mq_attr mqstat;
222 } mq_getsetattr;
223 struct {
224 mqd_t mqdes;
225 int sigev_signo;
226 } mq_notify;
227 struct {
228 mqd_t mqdes;
229 size_t msg_len;
230 unsigned int msg_prio;
231 struct timespec abs_timeout;
232 } mq_sendrecv;
233 struct {
234 int oflag;
235 mode_t mode;
236 struct mq_attr attr;
237 } mq_open;
238 struct {
239 pid_t pid;
240 struct audit_cap_data cap;
241 } capset;
242 };
243 int fds[2];
244
245 #if AUDIT_DEBUG
246 int put_count;
247 int ino_count;
248 #endif
249 };
250
251 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
open_arg(int flags,int mask)252 static inline int open_arg(int flags, int mask)
253 {
254 int n = ACC_MODE(flags);
255 if (flags & (O_TRUNC | O_CREAT))
256 n |= AUDIT_PERM_WRITE;
257 return n & mask;
258 }
259
audit_match_perm(struct audit_context * ctx,int mask)260 static int audit_match_perm(struct audit_context *ctx, int mask)
261 {
262 unsigned n;
263 if (unlikely(!ctx))
264 return 0;
265 n = ctx->major;
266
267 switch (audit_classify_syscall(ctx->arch, n)) {
268 case 0: /* native */
269 if ((mask & AUDIT_PERM_WRITE) &&
270 audit_match_class(AUDIT_CLASS_WRITE, n))
271 return 1;
272 if ((mask & AUDIT_PERM_READ) &&
273 audit_match_class(AUDIT_CLASS_READ, n))
274 return 1;
275 if ((mask & AUDIT_PERM_ATTR) &&
276 audit_match_class(AUDIT_CLASS_CHATTR, n))
277 return 1;
278 return 0;
279 case 1: /* 32bit on biarch */
280 if ((mask & AUDIT_PERM_WRITE) &&
281 audit_match_class(AUDIT_CLASS_WRITE_32, n))
282 return 1;
283 if ((mask & AUDIT_PERM_READ) &&
284 audit_match_class(AUDIT_CLASS_READ_32, n))
285 return 1;
286 if ((mask & AUDIT_PERM_ATTR) &&
287 audit_match_class(AUDIT_CLASS_CHATTR_32, n))
288 return 1;
289 return 0;
290 case 2: /* open */
291 return mask & ACC_MODE(ctx->argv[1]);
292 case 3: /* openat */
293 return mask & ACC_MODE(ctx->argv[2]);
294 case 4: /* socketcall */
295 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
296 case 5: /* execve */
297 return mask & AUDIT_PERM_EXEC;
298 default:
299 return 0;
300 }
301 }
302
audit_match_filetype(struct audit_context * ctx,int which)303 static int audit_match_filetype(struct audit_context *ctx, int which)
304 {
305 unsigned index = which & ~S_IFMT;
306 mode_t mode = which & S_IFMT;
307
308 if (unlikely(!ctx))
309 return 0;
310
311 if (index >= ctx->name_count)
312 return 0;
313 if (ctx->names[index].ino == -1)
314 return 0;
315 if ((ctx->names[index].mode ^ mode) & S_IFMT)
316 return 0;
317 return 1;
318 }
319
320 /*
321 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
322 * ->first_trees points to its beginning, ->trees - to the current end of data.
323 * ->tree_count is the number of free entries in array pointed to by ->trees.
324 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
325 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously,
326 * it's going to remain 1-element for almost any setup) until we free context itself.
327 * References in it _are_ dropped - at the same time we free/drop aux stuff.
328 */
329
330 #ifdef CONFIG_AUDIT_TREE
put_tree_ref(struct audit_context * ctx,struct audit_chunk * chunk)331 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
332 {
333 struct audit_tree_refs *p = ctx->trees;
334 int left = ctx->tree_count;
335 if (likely(left)) {
336 p->c[--left] = chunk;
337 ctx->tree_count = left;
338 return 1;
339 }
340 if (!p)
341 return 0;
342 p = p->next;
343 if (p) {
344 p->c[30] = chunk;
345 ctx->trees = p;
346 ctx->tree_count = 30;
347 return 1;
348 }
349 return 0;
350 }
351
grow_tree_refs(struct audit_context * ctx)352 static int grow_tree_refs(struct audit_context *ctx)
353 {
354 struct audit_tree_refs *p = ctx->trees;
355 ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
356 if (!ctx->trees) {
357 ctx->trees = p;
358 return 0;
359 }
360 if (p)
361 p->next = ctx->trees;
362 else
363 ctx->first_trees = ctx->trees;
364 ctx->tree_count = 31;
365 return 1;
366 }
367 #endif
368
unroll_tree_refs(struct audit_context * ctx,struct audit_tree_refs * p,int count)369 static void unroll_tree_refs(struct audit_context *ctx,
370 struct audit_tree_refs *p, int count)
371 {
372 #ifdef CONFIG_AUDIT_TREE
373 struct audit_tree_refs *q;
374 int n;
375 if (!p) {
376 /* we started with empty chain */
377 p = ctx->first_trees;
378 count = 31;
379 /* if the very first allocation has failed, nothing to do */
380 if (!p)
381 return;
382 }
383 n = count;
384 for (q = p; q != ctx->trees; q = q->next, n = 31) {
385 while (n--) {
386 audit_put_chunk(q->c[n]);
387 q->c[n] = NULL;
388 }
389 }
390 while (n-- > ctx->tree_count) {
391 audit_put_chunk(q->c[n]);
392 q->c[n] = NULL;
393 }
394 ctx->trees = p;
395 ctx->tree_count = count;
396 #endif
397 }
398
free_tree_refs(struct audit_context * ctx)399 static void free_tree_refs(struct audit_context *ctx)
400 {
401 struct audit_tree_refs *p, *q;
402 for (p = ctx->first_trees; p; p = q) {
403 q = p->next;
404 kfree(p);
405 }
406 }
407
match_tree_refs(struct audit_context * ctx,struct audit_tree * tree)408 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
409 {
410 #ifdef CONFIG_AUDIT_TREE
411 struct audit_tree_refs *p;
412 int n;
413 if (!tree)
414 return 0;
415 /* full ones */
416 for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
417 for (n = 0; n < 31; n++)
418 if (audit_tree_match(p->c[n], tree))
419 return 1;
420 }
421 /* partial */
422 if (p) {
423 for (n = ctx->tree_count; n < 31; n++)
424 if (audit_tree_match(p->c[n], tree))
425 return 1;
426 }
427 #endif
428 return 0;
429 }
430
431 /* Determine if any context name data matches a rule's watch data */
432 /* Compare a task_struct with an audit_rule. Return 1 on match, 0
433 * otherwise. */
audit_filter_rules(struct task_struct * tsk,struct audit_krule * rule,struct audit_context * ctx,struct audit_names * name,enum audit_state * state)434 static int audit_filter_rules(struct task_struct *tsk,
435 struct audit_krule *rule,
436 struct audit_context *ctx,
437 struct audit_names *name,
438 enum audit_state *state)
439 {
440 const struct cred *cred = get_task_cred(tsk);
441 int i, j, need_sid = 1;
442 u32 sid;
443
444 for (i = 0; i < rule->field_count; i++) {
445 struct audit_field *f = &rule->fields[i];
446 int result = 0;
447
448 switch (f->type) {
449 case AUDIT_PID:
450 result = audit_comparator(tsk->pid, f->op, f->val);
451 break;
452 case AUDIT_PPID:
453 if (ctx) {
454 if (!ctx->ppid)
455 ctx->ppid = sys_getppid();
456 result = audit_comparator(ctx->ppid, f->op, f->val);
457 }
458 break;
459 case AUDIT_UID:
460 result = audit_comparator(cred->uid, f->op, f->val);
461 break;
462 case AUDIT_EUID:
463 result = audit_comparator(cred->euid, f->op, f->val);
464 break;
465 case AUDIT_SUID:
466 result = audit_comparator(cred->suid, f->op, f->val);
467 break;
468 case AUDIT_FSUID:
469 result = audit_comparator(cred->fsuid, f->op, f->val);
470 break;
471 case AUDIT_GID:
472 result = audit_comparator(cred->gid, f->op, f->val);
473 break;
474 case AUDIT_EGID:
475 result = audit_comparator(cred->egid, f->op, f->val);
476 break;
477 case AUDIT_SGID:
478 result = audit_comparator(cred->sgid, f->op, f->val);
479 break;
480 case AUDIT_FSGID:
481 result = audit_comparator(cred->fsgid, f->op, f->val);
482 break;
483 case AUDIT_PERS:
484 result = audit_comparator(tsk->personality, f->op, f->val);
485 break;
486 case AUDIT_ARCH:
487 if (ctx)
488 result = audit_comparator(ctx->arch, f->op, f->val);
489 break;
490
491 case AUDIT_EXIT:
492 if (ctx && ctx->return_valid)
493 result = audit_comparator(ctx->return_code, f->op, f->val);
494 break;
495 case AUDIT_SUCCESS:
496 if (ctx && ctx->return_valid) {
497 if (f->val)
498 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
499 else
500 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
501 }
502 break;
503 case AUDIT_DEVMAJOR:
504 if (name)
505 result = audit_comparator(MAJOR(name->dev),
506 f->op, f->val);
507 else if (ctx) {
508 for (j = 0; j < ctx->name_count; j++) {
509 if (audit_comparator(MAJOR(ctx->names[j].dev), f->op, f->val)) {
510 ++result;
511 break;
512 }
513 }
514 }
515 break;
516 case AUDIT_DEVMINOR:
517 if (name)
518 result = audit_comparator(MINOR(name->dev),
519 f->op, f->val);
520 else if (ctx) {
521 for (j = 0; j < ctx->name_count; j++) {
522 if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) {
523 ++result;
524 break;
525 }
526 }
527 }
528 break;
529 case AUDIT_INODE:
530 if (name)
531 result = (name->ino == f->val);
532 else if (ctx) {
533 for (j = 0; j < ctx->name_count; j++) {
534 if (audit_comparator(ctx->names[j].ino, f->op, f->val)) {
535 ++result;
536 break;
537 }
538 }
539 }
540 break;
541 case AUDIT_WATCH:
542 if (name && rule->watch->ino != (unsigned long)-1)
543 result = (name->dev == rule->watch->dev &&
544 name->ino == rule->watch->ino);
545 break;
546 case AUDIT_DIR:
547 if (ctx)
548 result = match_tree_refs(ctx, rule->tree);
549 break;
550 case AUDIT_LOGINUID:
551 result = 0;
552 if (ctx)
553 result = audit_comparator(tsk->loginuid, f->op, f->val);
554 break;
555 case AUDIT_SUBJ_USER:
556 case AUDIT_SUBJ_ROLE:
557 case AUDIT_SUBJ_TYPE:
558 case AUDIT_SUBJ_SEN:
559 case AUDIT_SUBJ_CLR:
560 /* NOTE: this may return negative values indicating
561 a temporary error. We simply treat this as a
562 match for now to avoid losing information that
563 may be wanted. An error message will also be
564 logged upon error */
565 if (f->lsm_rule) {
566 if (need_sid) {
567 security_task_getsecid(tsk, &sid);
568 need_sid = 0;
569 }
570 result = security_audit_rule_match(sid, f->type,
571 f->op,
572 f->lsm_rule,
573 ctx);
574 }
575 break;
576 case AUDIT_OBJ_USER:
577 case AUDIT_OBJ_ROLE:
578 case AUDIT_OBJ_TYPE:
579 case AUDIT_OBJ_LEV_LOW:
580 case AUDIT_OBJ_LEV_HIGH:
581 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
582 also applies here */
583 if (f->lsm_rule) {
584 /* Find files that match */
585 if (name) {
586 result = security_audit_rule_match(
587 name->osid, f->type, f->op,
588 f->lsm_rule, ctx);
589 } else if (ctx) {
590 for (j = 0; j < ctx->name_count; j++) {
591 if (security_audit_rule_match(
592 ctx->names[j].osid,
593 f->type, f->op,
594 f->lsm_rule, ctx)) {
595 ++result;
596 break;
597 }
598 }
599 }
600 /* Find ipc objects that match */
601 if (!ctx || ctx->type != AUDIT_IPC)
602 break;
603 if (security_audit_rule_match(ctx->ipc.osid,
604 f->type, f->op,
605 f->lsm_rule, ctx))
606 ++result;
607 }
608 break;
609 case AUDIT_ARG0:
610 case AUDIT_ARG1:
611 case AUDIT_ARG2:
612 case AUDIT_ARG3:
613 if (ctx)
614 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
615 break;
616 case AUDIT_FILTERKEY:
617 /* ignore this field for filtering */
618 result = 1;
619 break;
620 case AUDIT_PERM:
621 result = audit_match_perm(ctx, f->val);
622 break;
623 case AUDIT_FILETYPE:
624 result = audit_match_filetype(ctx, f->val);
625 break;
626 }
627
628 if (!result) {
629 put_cred(cred);
630 return 0;
631 }
632 }
633
634 if (ctx) {
635 if (rule->prio <= ctx->prio)
636 return 0;
637 if (rule->filterkey) {
638 kfree(ctx->filterkey);
639 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
640 }
641 ctx->prio = rule->prio;
642 }
643 switch (rule->action) {
644 case AUDIT_NEVER: *state = AUDIT_DISABLED; break;
645 case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break;
646 }
647 put_cred(cred);
648 return 1;
649 }
650
651 /* At process creation time, we can determine if system-call auditing is
652 * completely disabled for this task. Since we only have the task
653 * structure at this point, we can only check uid and gid.
654 */
audit_filter_task(struct task_struct * tsk,char ** key)655 static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
656 {
657 struct audit_entry *e;
658 enum audit_state state;
659
660 rcu_read_lock();
661 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
662 if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) {
663 if (state == AUDIT_RECORD_CONTEXT)
664 *key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
665 rcu_read_unlock();
666 return state;
667 }
668 }
669 rcu_read_unlock();
670 return AUDIT_BUILD_CONTEXT;
671 }
672
673 /* At syscall entry and exit time, this filter is called if the
674 * audit_state is not low enough that auditing cannot take place, but is
675 * also not high enough that we already know we have to write an audit
676 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
677 */
audit_filter_syscall(struct task_struct * tsk,struct audit_context * ctx,struct list_head * list)678 static enum audit_state audit_filter_syscall(struct task_struct *tsk,
679 struct audit_context *ctx,
680 struct list_head *list)
681 {
682 struct audit_entry *e;
683 enum audit_state state;
684
685 if (audit_pid && tsk->tgid == audit_pid)
686 return AUDIT_DISABLED;
687
688 rcu_read_lock();
689 if (!list_empty(list)) {
690 int word = AUDIT_WORD(ctx->major);
691 int bit = AUDIT_BIT(ctx->major);
692
693 list_for_each_entry_rcu(e, list, list) {
694 if ((e->rule.mask[word] & bit) == bit &&
695 audit_filter_rules(tsk, &e->rule, ctx, NULL,
696 &state)) {
697 rcu_read_unlock();
698 ctx->current_state = state;
699 return state;
700 }
701 }
702 }
703 rcu_read_unlock();
704 return AUDIT_BUILD_CONTEXT;
705 }
706
707 /* At syscall exit time, this filter is called if any audit_names[] have been
708 * collected during syscall processing. We only check rules in sublists at hash
709 * buckets applicable to the inode numbers in audit_names[].
710 * Regarding audit_state, same rules apply as for audit_filter_syscall().
711 */
audit_filter_inodes(struct task_struct * tsk,struct audit_context * ctx)712 void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
713 {
714 int i;
715 struct audit_entry *e;
716 enum audit_state state;
717
718 if (audit_pid && tsk->tgid == audit_pid)
719 return;
720
721 rcu_read_lock();
722 for (i = 0; i < ctx->name_count; i++) {
723 int word = AUDIT_WORD(ctx->major);
724 int bit = AUDIT_BIT(ctx->major);
725 struct audit_names *n = &ctx->names[i];
726 int h = audit_hash_ino((u32)n->ino);
727 struct list_head *list = &audit_inode_hash[h];
728
729 if (list_empty(list))
730 continue;
731
732 list_for_each_entry_rcu(e, list, list) {
733 if ((e->rule.mask[word] & bit) == bit &&
734 audit_filter_rules(tsk, &e->rule, ctx, n, &state)) {
735 rcu_read_unlock();
736 ctx->current_state = state;
737 return;
738 }
739 }
740 }
741 rcu_read_unlock();
742 }
743
audit_set_auditable(struct audit_context * ctx)744 static void audit_set_auditable(struct audit_context *ctx)
745 {
746 if (!ctx->prio) {
747 ctx->prio = 1;
748 ctx->current_state = AUDIT_RECORD_CONTEXT;
749 }
750 }
751
audit_get_context(struct task_struct * tsk,int return_valid,int return_code)752 static inline struct audit_context *audit_get_context(struct task_struct *tsk,
753 int return_valid,
754 int return_code)
755 {
756 struct audit_context *context = tsk->audit_context;
757
758 if (likely(!context))
759 return NULL;
760 context->return_valid = return_valid;
761
762 /*
763 * we need to fix up the return code in the audit logs if the actual
764 * return codes are later going to be fixed up by the arch specific
765 * signal handlers
766 *
767 * This is actually a test for:
768 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
769 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
770 *
771 * but is faster than a bunch of ||
772 */
773 if (unlikely(return_code <= -ERESTARTSYS) &&
774 (return_code >= -ERESTART_RESTARTBLOCK) &&
775 (return_code != -ENOIOCTLCMD))
776 context->return_code = -EINTR;
777 else
778 context->return_code = return_code;
779
780 if (context->in_syscall && !context->dummy) {
781 audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
782 audit_filter_inodes(tsk, context);
783 }
784
785 tsk->audit_context = NULL;
786 return context;
787 }
788
audit_free_names(struct audit_context * context)789 static inline void audit_free_names(struct audit_context *context)
790 {
791 int i;
792
793 #if AUDIT_DEBUG == 2
794 if (context->put_count + context->ino_count != context->name_count) {
795 printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
796 " name_count=%d put_count=%d"
797 " ino_count=%d [NOT freeing]\n",
798 __FILE__, __LINE__,
799 context->serial, context->major, context->in_syscall,
800 context->name_count, context->put_count,
801 context->ino_count);
802 for (i = 0; i < context->name_count; i++) {
803 printk(KERN_ERR "names[%d] = %p = %s\n", i,
804 context->names[i].name,
805 context->names[i].name ?: "(null)");
806 }
807 dump_stack();
808 return;
809 }
810 #endif
811 #if AUDIT_DEBUG
812 context->put_count = 0;
813 context->ino_count = 0;
814 #endif
815
816 for (i = 0; i < context->name_count; i++) {
817 if (context->names[i].name && context->names[i].name_put)
818 __putname(context->names[i].name);
819 }
820 context->name_count = 0;
821 path_put(&context->pwd);
822 context->pwd.dentry = NULL;
823 context->pwd.mnt = NULL;
824 }
825
audit_free_aux(struct audit_context * context)826 static inline void audit_free_aux(struct audit_context *context)
827 {
828 struct audit_aux_data *aux;
829
830 while ((aux = context->aux)) {
831 context->aux = aux->next;
832 kfree(aux);
833 }
834 while ((aux = context->aux_pids)) {
835 context->aux_pids = aux->next;
836 kfree(aux);
837 }
838 }
839
audit_zero_context(struct audit_context * context,enum audit_state state)840 static inline void audit_zero_context(struct audit_context *context,
841 enum audit_state state)
842 {
843 memset(context, 0, sizeof(*context));
844 context->state = state;
845 context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
846 }
847
audit_alloc_context(enum audit_state state)848 static inline struct audit_context *audit_alloc_context(enum audit_state state)
849 {
850 struct audit_context *context;
851
852 if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
853 return NULL;
854 audit_zero_context(context, state);
855 return context;
856 }
857
858 /**
859 * audit_alloc - allocate an audit context block for a task
860 * @tsk: task
861 *
862 * Filter on the task information and allocate a per-task audit context
863 * if necessary. Doing so turns on system call auditing for the
864 * specified task. This is called from copy_process, so no lock is
865 * needed.
866 */
audit_alloc(struct task_struct * tsk)867 int audit_alloc(struct task_struct *tsk)
868 {
869 struct audit_context *context;
870 enum audit_state state;
871 char *key = NULL;
872
873 if (likely(!audit_ever_enabled))
874 return 0; /* Return if not auditing. */
875
876 state = audit_filter_task(tsk, &key);
877 if (likely(state == AUDIT_DISABLED))
878 return 0;
879
880 if (!(context = audit_alloc_context(state))) {
881 kfree(key);
882 audit_log_lost("out of memory in audit_alloc");
883 return -ENOMEM;
884 }
885 context->filterkey = key;
886
887 tsk->audit_context = context;
888 set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
889 return 0;
890 }
891
audit_free_context(struct audit_context * context)892 static inline void audit_free_context(struct audit_context *context)
893 {
894 struct audit_context *previous;
895 int count = 0;
896
897 do {
898 previous = context->previous;
899 if (previous || (count && count < 10)) {
900 ++count;
901 printk(KERN_ERR "audit(:%d): major=%d name_count=%d:"
902 " freeing multiple contexts (%d)\n",
903 context->serial, context->major,
904 context->name_count, count);
905 }
906 audit_free_names(context);
907 unroll_tree_refs(context, NULL, 0);
908 free_tree_refs(context);
909 audit_free_aux(context);
910 kfree(context->filterkey);
911 kfree(context->sockaddr);
912 kfree(context);
913 context = previous;
914 } while (context);
915 if (count >= 10)
916 printk(KERN_ERR "audit: freed %d contexts\n", count);
917 }
918
audit_log_task_context(struct audit_buffer * ab)919 void audit_log_task_context(struct audit_buffer *ab)
920 {
921 char *ctx = NULL;
922 unsigned len;
923 int error;
924 u32 sid;
925
926 security_task_getsecid(current, &sid);
927 if (!sid)
928 return;
929
930 error = security_secid_to_secctx(sid, &ctx, &len);
931 if (error) {
932 if (error != -EINVAL)
933 goto error_path;
934 return;
935 }
936
937 audit_log_format(ab, " subj=%s", ctx);
938 security_release_secctx(ctx, len);
939 return;
940
941 error_path:
942 audit_panic("error in audit_log_task_context");
943 return;
944 }
945
946 EXPORT_SYMBOL(audit_log_task_context);
947
audit_log_task_info(struct audit_buffer * ab,struct task_struct * tsk)948 static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
949 {
950 char name[sizeof(tsk->comm)];
951 struct mm_struct *mm = tsk->mm;
952 struct vm_area_struct *vma;
953
954 /* tsk == current */
955
956 get_task_comm(name, tsk);
957 audit_log_format(ab, " comm=");
958 audit_log_untrustedstring(ab, name);
959
960 if (mm) {
961 down_read(&mm->mmap_sem);
962 vma = mm->mmap;
963 while (vma) {
964 if ((vma->vm_flags & VM_EXECUTABLE) &&
965 vma->vm_file) {
966 audit_log_d_path(ab, "exe=",
967 &vma->vm_file->f_path);
968 break;
969 }
970 vma = vma->vm_next;
971 }
972 up_read(&mm->mmap_sem);
973 }
974 audit_log_task_context(ab);
975 }
976
audit_log_pid_context(struct audit_context * context,pid_t pid,uid_t auid,uid_t uid,unsigned int sessionid,u32 sid,char * comm)977 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
978 uid_t auid, uid_t uid, unsigned int sessionid,
979 u32 sid, char *comm)
980 {
981 struct audit_buffer *ab;
982 char *ctx = NULL;
983 u32 len;
984 int rc = 0;
985
986 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
987 if (!ab)
988 return rc;
989
990 audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid,
991 uid, sessionid);
992 if (security_secid_to_secctx(sid, &ctx, &len)) {
993 audit_log_format(ab, " obj=(none)");
994 rc = 1;
995 } else {
996 audit_log_format(ab, " obj=%s", ctx);
997 security_release_secctx(ctx, len);
998 }
999 audit_log_format(ab, " ocomm=");
1000 audit_log_untrustedstring(ab, comm);
1001 audit_log_end(ab);
1002
1003 return rc;
1004 }
1005
1006 /*
1007 * to_send and len_sent accounting are very loose estimates. We aren't
1008 * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being
1009 * within about 500 bytes (next page boundry)
1010 *
1011 * why snprintf? an int is up to 12 digits long. if we just assumed when
1012 * logging that a[%d]= was going to be 16 characters long we would be wasting
1013 * space in every audit message. In one 7500 byte message we can log up to
1014 * about 1000 min size arguments. That comes down to about 50% waste of space
1015 * if we didn't do the snprintf to find out how long arg_num_len was.
1016 */
audit_log_single_execve_arg(struct audit_context * context,struct audit_buffer ** ab,int arg_num,size_t * len_sent,const char __user * p,char * buf)1017 static int audit_log_single_execve_arg(struct audit_context *context,
1018 struct audit_buffer **ab,
1019 int arg_num,
1020 size_t *len_sent,
1021 const char __user *p,
1022 char *buf)
1023 {
1024 char arg_num_len_buf[12];
1025 const char __user *tmp_p = p;
1026 /* how many digits are in arg_num? 3 is the length of a=\n */
1027 size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 3;
1028 size_t len, len_left, to_send;
1029 size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN;
1030 unsigned int i, has_cntl = 0, too_long = 0;
1031 int ret;
1032
1033 /* strnlen_user includes the null we don't want to send */
1034 len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1035
1036 /*
1037 * We just created this mm, if we can't find the strings
1038 * we just copied into it something is _very_ wrong. Similar
1039 * for strings that are too long, we should not have created
1040 * any.
1041 */
1042 if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
1043 WARN_ON(1);
1044 send_sig(SIGKILL, current, 0);
1045 return -1;
1046 }
1047
1048 /* walk the whole argument looking for non-ascii chars */
1049 do {
1050 if (len_left > MAX_EXECVE_AUDIT_LEN)
1051 to_send = MAX_EXECVE_AUDIT_LEN;
1052 else
1053 to_send = len_left;
1054 ret = copy_from_user(buf, tmp_p, to_send);
1055 /*
1056 * There is no reason for this copy to be short. We just
1057 * copied them here, and the mm hasn't been exposed to user-
1058 * space yet.
1059 */
1060 if (ret) {
1061 WARN_ON(1);
1062 send_sig(SIGKILL, current, 0);
1063 return -1;
1064 }
1065 buf[to_send] = '\0';
1066 has_cntl = audit_string_contains_control(buf, to_send);
1067 if (has_cntl) {
1068 /*
1069 * hex messages get logged as 2 bytes, so we can only
1070 * send half as much in each message
1071 */
1072 max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2;
1073 break;
1074 }
1075 len_left -= to_send;
1076 tmp_p += to_send;
1077 } while (len_left > 0);
1078
1079 len_left = len;
1080
1081 if (len > max_execve_audit_len)
1082 too_long = 1;
1083
1084 /* rewalk the argument actually logging the message */
1085 for (i = 0; len_left > 0; i++) {
1086 int room_left;
1087
1088 if (len_left > max_execve_audit_len)
1089 to_send = max_execve_audit_len;
1090 else
1091 to_send = len_left;
1092
1093 /* do we have space left to send this argument in this ab? */
1094 room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent;
1095 if (has_cntl)
1096 room_left -= (to_send * 2);
1097 else
1098 room_left -= to_send;
1099 if (room_left < 0) {
1100 *len_sent = 0;
1101 audit_log_end(*ab);
1102 *ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE);
1103 if (!*ab)
1104 return 0;
1105 }
1106
1107 /*
1108 * first record needs to say how long the original string was
1109 * so we can be sure nothing was lost.
1110 */
1111 if ((i == 0) && (too_long))
1112 audit_log_format(*ab, "a%d_len=%zu ", arg_num,
1113 has_cntl ? 2*len : len);
1114
1115 /*
1116 * normally arguments are small enough to fit and we already
1117 * filled buf above when we checked for control characters
1118 * so don't bother with another copy_from_user
1119 */
1120 if (len >= max_execve_audit_len)
1121 ret = copy_from_user(buf, p, to_send);
1122 else
1123 ret = 0;
1124 if (ret) {
1125 WARN_ON(1);
1126 send_sig(SIGKILL, current, 0);
1127 return -1;
1128 }
1129 buf[to_send] = '\0';
1130
1131 /* actually log it */
1132 audit_log_format(*ab, "a%d", arg_num);
1133 if (too_long)
1134 audit_log_format(*ab, "[%d]", i);
1135 audit_log_format(*ab, "=");
1136 if (has_cntl)
1137 audit_log_n_hex(*ab, buf, to_send);
1138 else
1139 audit_log_format(*ab, "\"%s\"", buf);
1140 audit_log_format(*ab, "\n");
1141
1142 p += to_send;
1143 len_left -= to_send;
1144 *len_sent += arg_num_len;
1145 if (has_cntl)
1146 *len_sent += to_send * 2;
1147 else
1148 *len_sent += to_send;
1149 }
1150 /* include the null we didn't log */
1151 return len + 1;
1152 }
1153
audit_log_execve_info(struct audit_context * context,struct audit_buffer ** ab,struct audit_aux_data_execve * axi)1154 static void audit_log_execve_info(struct audit_context *context,
1155 struct audit_buffer **ab,
1156 struct audit_aux_data_execve *axi)
1157 {
1158 int i;
1159 size_t len, len_sent = 0;
1160 const char __user *p;
1161 char *buf;
1162
1163 if (axi->mm != current->mm)
1164 return; /* execve failed, no additional info */
1165
1166 p = (const char __user *)axi->mm->arg_start;
1167
1168 audit_log_format(*ab, "argc=%d ", axi->argc);
1169
1170 /*
1171 * we need some kernel buffer to hold the userspace args. Just
1172 * allocate one big one rather than allocating one of the right size
1173 * for every single argument inside audit_log_single_execve_arg()
1174 * should be <8k allocation so should be pretty safe.
1175 */
1176 buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1177 if (!buf) {
1178 audit_panic("out of memory for argv string\n");
1179 return;
1180 }
1181
1182 for (i = 0; i < axi->argc; i++) {
1183 len = audit_log_single_execve_arg(context, ab, i,
1184 &len_sent, p, buf);
1185 if (len <= 0)
1186 break;
1187 p += len;
1188 }
1189 kfree(buf);
1190 }
1191
audit_log_cap(struct audit_buffer * ab,char * prefix,kernel_cap_t * cap)1192 static void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap)
1193 {
1194 int i;
1195
1196 audit_log_format(ab, " %s=", prefix);
1197 CAP_FOR_EACH_U32(i) {
1198 audit_log_format(ab, "%08x", cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]);
1199 }
1200 }
1201
audit_log_fcaps(struct audit_buffer * ab,struct audit_names * name)1202 static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
1203 {
1204 kernel_cap_t *perm = &name->fcap.permitted;
1205 kernel_cap_t *inh = &name->fcap.inheritable;
1206 int log = 0;
1207
1208 if (!cap_isclear(*perm)) {
1209 audit_log_cap(ab, "cap_fp", perm);
1210 log = 1;
1211 }
1212 if (!cap_isclear(*inh)) {
1213 audit_log_cap(ab, "cap_fi", inh);
1214 log = 1;
1215 }
1216
1217 if (log)
1218 audit_log_format(ab, " cap_fe=%d cap_fver=%x", name->fcap.fE, name->fcap_ver);
1219 }
1220
show_special(struct audit_context * context,int * call_panic)1221 static void show_special(struct audit_context *context, int *call_panic)
1222 {
1223 struct audit_buffer *ab;
1224 int i;
1225
1226 ab = audit_log_start(context, GFP_KERNEL, context->type);
1227 if (!ab)
1228 return;
1229
1230 switch (context->type) {
1231 case AUDIT_SOCKETCALL: {
1232 int nargs = context->socketcall.nargs;
1233 audit_log_format(ab, "nargs=%d", nargs);
1234 for (i = 0; i < nargs; i++)
1235 audit_log_format(ab, " a%d=%lx", i,
1236 context->socketcall.args[i]);
1237 break; }
1238 case AUDIT_IPC: {
1239 u32 osid = context->ipc.osid;
1240
1241 audit_log_format(ab, "ouid=%u ogid=%u mode=%#o",
1242 context->ipc.uid, context->ipc.gid, context->ipc.mode);
1243 if (osid) {
1244 char *ctx = NULL;
1245 u32 len;
1246 if (security_secid_to_secctx(osid, &ctx, &len)) {
1247 audit_log_format(ab, " osid=%u", osid);
1248 *call_panic = 1;
1249 } else {
1250 audit_log_format(ab, " obj=%s", ctx);
1251 security_release_secctx(ctx, len);
1252 }
1253 }
1254 if (context->ipc.has_perm) {
1255 audit_log_end(ab);
1256 ab = audit_log_start(context, GFP_KERNEL,
1257 AUDIT_IPC_SET_PERM);
1258 audit_log_format(ab,
1259 "qbytes=%lx ouid=%u ogid=%u mode=%#o",
1260 context->ipc.qbytes,
1261 context->ipc.perm_uid,
1262 context->ipc.perm_gid,
1263 context->ipc.perm_mode);
1264 if (!ab)
1265 return;
1266 }
1267 break; }
1268 case AUDIT_MQ_OPEN: {
1269 audit_log_format(ab,
1270 "oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld "
1271 "mq_msgsize=%ld mq_curmsgs=%ld",
1272 context->mq_open.oflag, context->mq_open.mode,
1273 context->mq_open.attr.mq_flags,
1274 context->mq_open.attr.mq_maxmsg,
1275 context->mq_open.attr.mq_msgsize,
1276 context->mq_open.attr.mq_curmsgs);
1277 break; }
1278 case AUDIT_MQ_SENDRECV: {
1279 audit_log_format(ab,
1280 "mqdes=%d msg_len=%zd msg_prio=%u "
1281 "abs_timeout_sec=%ld abs_timeout_nsec=%ld",
1282 context->mq_sendrecv.mqdes,
1283 context->mq_sendrecv.msg_len,
1284 context->mq_sendrecv.msg_prio,
1285 context->mq_sendrecv.abs_timeout.tv_sec,
1286 context->mq_sendrecv.abs_timeout.tv_nsec);
1287 break; }
1288 case AUDIT_MQ_NOTIFY: {
1289 audit_log_format(ab, "mqdes=%d sigev_signo=%d",
1290 context->mq_notify.mqdes,
1291 context->mq_notify.sigev_signo);
1292 break; }
1293 case AUDIT_MQ_GETSETATTR: {
1294 struct mq_attr *attr = &context->mq_getsetattr.mqstat;
1295 audit_log_format(ab,
1296 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1297 "mq_curmsgs=%ld ",
1298 context->mq_getsetattr.mqdes,
1299 attr->mq_flags, attr->mq_maxmsg,
1300 attr->mq_msgsize, attr->mq_curmsgs);
1301 break; }
1302 case AUDIT_CAPSET: {
1303 audit_log_format(ab, "pid=%d", context->capset.pid);
1304 audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
1305 audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
1306 audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
1307 break; }
1308 }
1309 audit_log_end(ab);
1310 }
1311
audit_log_exit(struct audit_context * context,struct task_struct * tsk)1312 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
1313 {
1314 const struct cred *cred;
1315 int i, call_panic = 0;
1316 struct audit_buffer *ab;
1317 struct audit_aux_data *aux;
1318 const char *tty;
1319
1320 /* tsk == current */
1321 context->pid = tsk->pid;
1322 if (!context->ppid)
1323 context->ppid = sys_getppid();
1324 cred = current_cred();
1325 context->uid = cred->uid;
1326 context->gid = cred->gid;
1327 context->euid = cred->euid;
1328 context->suid = cred->suid;
1329 context->fsuid = cred->fsuid;
1330 context->egid = cred->egid;
1331 context->sgid = cred->sgid;
1332 context->fsgid = cred->fsgid;
1333 context->personality = tsk->personality;
1334
1335 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1336 if (!ab)
1337 return; /* audit_panic has been called */
1338 audit_log_format(ab, "arch=%x syscall=%d",
1339 context->arch, context->major);
1340 if (context->personality != PER_LINUX)
1341 audit_log_format(ab, " per=%lx", context->personality);
1342 if (context->return_valid)
1343 audit_log_format(ab, " success=%s exit=%ld",
1344 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
1345 context->return_code);
1346
1347 spin_lock_irq(&tsk->sighand->siglock);
1348 if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
1349 tty = tsk->signal->tty->name;
1350 else
1351 tty = "(none)";
1352 spin_unlock_irq(&tsk->sighand->siglock);
1353
1354 audit_log_format(ab,
1355 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
1356 " ppid=%d pid=%d auid=%u uid=%u gid=%u"
1357 " euid=%u suid=%u fsuid=%u"
1358 " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
1359 context->argv[0],
1360 context->argv[1],
1361 context->argv[2],
1362 context->argv[3],
1363 context->name_count,
1364 context->ppid,
1365 context->pid,
1366 tsk->loginuid,
1367 context->uid,
1368 context->gid,
1369 context->euid, context->suid, context->fsuid,
1370 context->egid, context->sgid, context->fsgid, tty,
1371 tsk->sessionid);
1372
1373
1374 audit_log_task_info(ab, tsk);
1375 if (context->filterkey) {
1376 audit_log_format(ab, " key=");
1377 audit_log_untrustedstring(ab, context->filterkey);
1378 } else
1379 audit_log_format(ab, " key=(null)");
1380 audit_log_end(ab);
1381
1382 for (aux = context->aux; aux; aux = aux->next) {
1383
1384 ab = audit_log_start(context, GFP_KERNEL, aux->type);
1385 if (!ab)
1386 continue; /* audit_panic has been called */
1387
1388 switch (aux->type) {
1389
1390 case AUDIT_EXECVE: {
1391 struct audit_aux_data_execve *axi = (void *)aux;
1392 audit_log_execve_info(context, &ab, axi);
1393 break; }
1394
1395 case AUDIT_BPRM_FCAPS: {
1396 struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
1397 audit_log_format(ab, "fver=%x", axs->fcap_ver);
1398 audit_log_cap(ab, "fp", &axs->fcap.permitted);
1399 audit_log_cap(ab, "fi", &axs->fcap.inheritable);
1400 audit_log_format(ab, " fe=%d", axs->fcap.fE);
1401 audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
1402 audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
1403 audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
1404 audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted);
1405 audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable);
1406 audit_log_cap(ab, "new_pe", &axs->new_pcap.effective);
1407 break; }
1408
1409 }
1410 audit_log_end(ab);
1411 }
1412
1413 if (context->type)
1414 show_special(context, &call_panic);
1415
1416 if (context->fds[0] >= 0) {
1417 ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
1418 if (ab) {
1419 audit_log_format(ab, "fd0=%d fd1=%d",
1420 context->fds[0], context->fds[1]);
1421 audit_log_end(ab);
1422 }
1423 }
1424
1425 if (context->sockaddr_len) {
1426 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
1427 if (ab) {
1428 audit_log_format(ab, "saddr=");
1429 audit_log_n_hex(ab, (void *)context->sockaddr,
1430 context->sockaddr_len);
1431 audit_log_end(ab);
1432 }
1433 }
1434
1435 for (aux = context->aux_pids; aux; aux = aux->next) {
1436 struct audit_aux_data_pids *axs = (void *)aux;
1437
1438 for (i = 0; i < axs->pid_count; i++)
1439 if (audit_log_pid_context(context, axs->target_pid[i],
1440 axs->target_auid[i],
1441 axs->target_uid[i],
1442 axs->target_sessionid[i],
1443 axs->target_sid[i],
1444 axs->target_comm[i]))
1445 call_panic = 1;
1446 }
1447
1448 if (context->target_pid &&
1449 audit_log_pid_context(context, context->target_pid,
1450 context->target_auid, context->target_uid,
1451 context->target_sessionid,
1452 context->target_sid, context->target_comm))
1453 call_panic = 1;
1454
1455 if (context->pwd.dentry && context->pwd.mnt) {
1456 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1457 if (ab) {
1458 audit_log_d_path(ab, "cwd=", &context->pwd);
1459 audit_log_end(ab);
1460 }
1461 }
1462 for (i = 0; i < context->name_count; i++) {
1463 struct audit_names *n = &context->names[i];
1464
1465 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1466 if (!ab)
1467 continue; /* audit_panic has been called */
1468
1469 audit_log_format(ab, "item=%d", i);
1470
1471 if (n->name) {
1472 switch(n->name_len) {
1473 case AUDIT_NAME_FULL:
1474 /* log the full path */
1475 audit_log_format(ab, " name=");
1476 audit_log_untrustedstring(ab, n->name);
1477 break;
1478 case 0:
1479 /* name was specified as a relative path and the
1480 * directory component is the cwd */
1481 audit_log_d_path(ab, " name=", &context->pwd);
1482 break;
1483 default:
1484 /* log the name's directory component */
1485 audit_log_format(ab, " name=");
1486 audit_log_n_untrustedstring(ab, n->name,
1487 n->name_len);
1488 }
1489 } else
1490 audit_log_format(ab, " name=(null)");
1491
1492 if (n->ino != (unsigned long)-1) {
1493 audit_log_format(ab, " inode=%lu"
1494 " dev=%02x:%02x mode=%#o"
1495 " ouid=%u ogid=%u rdev=%02x:%02x",
1496 n->ino,
1497 MAJOR(n->dev),
1498 MINOR(n->dev),
1499 n->mode,
1500 n->uid,
1501 n->gid,
1502 MAJOR(n->rdev),
1503 MINOR(n->rdev));
1504 }
1505 if (n->osid != 0) {
1506 char *ctx = NULL;
1507 u32 len;
1508 if (security_secid_to_secctx(
1509 n->osid, &ctx, &len)) {
1510 audit_log_format(ab, " osid=%u", n->osid);
1511 call_panic = 2;
1512 } else {
1513 audit_log_format(ab, " obj=%s", ctx);
1514 security_release_secctx(ctx, len);
1515 }
1516 }
1517
1518 audit_log_fcaps(ab, n);
1519
1520 audit_log_end(ab);
1521 }
1522
1523 /* Send end of event record to help user space know we are finished */
1524 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1525 if (ab)
1526 audit_log_end(ab);
1527 if (call_panic)
1528 audit_panic("error converting sid to string");
1529 }
1530
1531 /**
1532 * audit_free - free a per-task audit context
1533 * @tsk: task whose audit context block to free
1534 *
1535 * Called from copy_process and do_exit
1536 */
audit_free(struct task_struct * tsk)1537 void audit_free(struct task_struct *tsk)
1538 {
1539 struct audit_context *context;
1540
1541 context = audit_get_context(tsk, 0, 0);
1542 if (likely(!context))
1543 return;
1544
1545 /* Check for system calls that do not go through the exit
1546 * function (e.g., exit_group), then free context block.
1547 * We use GFP_ATOMIC here because we might be doing this
1548 * in the context of the idle thread */
1549 /* that can happen only if we are called from do_exit() */
1550 if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1551 audit_log_exit(context, tsk);
1552
1553 audit_free_context(context);
1554 }
1555
1556 /**
1557 * audit_syscall_entry - fill in an audit record at syscall entry
1558 * @arch: architecture type
1559 * @major: major syscall type (function)
1560 * @a1: additional syscall register 1
1561 * @a2: additional syscall register 2
1562 * @a3: additional syscall register 3
1563 * @a4: additional syscall register 4
1564 *
1565 * Fill in audit context at syscall entry. This only happens if the
1566 * audit context was created when the task was created and the state or
1567 * filters demand the audit context be built. If the state from the
1568 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1569 * then the record will be written at syscall exit time (otherwise, it
1570 * will only be written if another part of the kernel requests that it
1571 * be written).
1572 */
audit_syscall_entry(int arch,int major,unsigned long a1,unsigned long a2,unsigned long a3,unsigned long a4)1573 void audit_syscall_entry(int arch, int major,
1574 unsigned long a1, unsigned long a2,
1575 unsigned long a3, unsigned long a4)
1576 {
1577 struct task_struct *tsk = current;
1578 struct audit_context *context = tsk->audit_context;
1579 enum audit_state state;
1580
1581 if (unlikely(!context))
1582 return;
1583
1584 /*
1585 * This happens only on certain architectures that make system
1586 * calls in kernel_thread via the entry.S interface, instead of
1587 * with direct calls. (If you are porting to a new
1588 * architecture, hitting this condition can indicate that you
1589 * got the _exit/_leave calls backward in entry.S.)
1590 *
1591 * i386 no
1592 * x86_64 no
1593 * ppc64 yes (see arch/powerpc/platforms/iseries/misc.S)
1594 *
1595 * This also happens with vm86 emulation in a non-nested manner
1596 * (entries without exits), so this case must be caught.
1597 */
1598 if (context->in_syscall) {
1599 struct audit_context *newctx;
1600
1601 #if AUDIT_DEBUG
1602 printk(KERN_ERR
1603 "audit(:%d) pid=%d in syscall=%d;"
1604 " entering syscall=%d\n",
1605 context->serial, tsk->pid, context->major, major);
1606 #endif
1607 newctx = audit_alloc_context(context->state);
1608 if (newctx) {
1609 newctx->previous = context;
1610 context = newctx;
1611 tsk->audit_context = newctx;
1612 } else {
1613 /* If we can't alloc a new context, the best we
1614 * can do is to leak memory (any pending putname
1615 * will be lost). The only other alternative is
1616 * to abandon auditing. */
1617 audit_zero_context(context, context->state);
1618 }
1619 }
1620 BUG_ON(context->in_syscall || context->name_count);
1621
1622 if (!audit_enabled)
1623 return;
1624
1625 context->arch = arch;
1626 context->major = major;
1627 context->argv[0] = a1;
1628 context->argv[1] = a2;
1629 context->argv[2] = a3;
1630 context->argv[3] = a4;
1631
1632 state = context->state;
1633 context->dummy = !audit_n_rules;
1634 if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
1635 context->prio = 0;
1636 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1637 }
1638 if (likely(state == AUDIT_DISABLED))
1639 return;
1640
1641 context->serial = 0;
1642 context->ctime = CURRENT_TIME;
1643 context->in_syscall = 1;
1644 context->current_state = state;
1645 context->ppid = 0;
1646 }
1647
audit_finish_fork(struct task_struct * child)1648 void audit_finish_fork(struct task_struct *child)
1649 {
1650 struct audit_context *ctx = current->audit_context;
1651 struct audit_context *p = child->audit_context;
1652 if (!p || !ctx)
1653 return;
1654 if (!ctx->in_syscall || ctx->current_state != AUDIT_RECORD_CONTEXT)
1655 return;
1656 p->arch = ctx->arch;
1657 p->major = ctx->major;
1658 memcpy(p->argv, ctx->argv, sizeof(ctx->argv));
1659 p->ctime = ctx->ctime;
1660 p->dummy = ctx->dummy;
1661 p->in_syscall = ctx->in_syscall;
1662 p->filterkey = kstrdup(ctx->filterkey, GFP_KERNEL);
1663 p->ppid = current->pid;
1664 p->prio = ctx->prio;
1665 p->current_state = ctx->current_state;
1666 }
1667
1668 /**
1669 * audit_syscall_exit - deallocate audit context after a system call
1670 * @valid: success/failure flag
1671 * @return_code: syscall return value
1672 *
1673 * Tear down after system call. If the audit context has been marked as
1674 * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1675 * filtering, or because some other part of the kernel write an audit
1676 * message), then write out the syscall information. In call cases,
1677 * free the names stored from getname().
1678 */
audit_syscall_exit(int valid,long return_code)1679 void audit_syscall_exit(int valid, long return_code)
1680 {
1681 struct task_struct *tsk = current;
1682 struct audit_context *context;
1683
1684 context = audit_get_context(tsk, valid, return_code);
1685
1686 if (likely(!context))
1687 return;
1688
1689 if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1690 audit_log_exit(context, tsk);
1691
1692 context->in_syscall = 0;
1693 context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
1694
1695 if (context->previous) {
1696 struct audit_context *new_context = context->previous;
1697 context->previous = NULL;
1698 audit_free_context(context);
1699 tsk->audit_context = new_context;
1700 } else {
1701 audit_free_names(context);
1702 unroll_tree_refs(context, NULL, 0);
1703 audit_free_aux(context);
1704 context->aux = NULL;
1705 context->aux_pids = NULL;
1706 context->target_pid = 0;
1707 context->target_sid = 0;
1708 context->sockaddr_len = 0;
1709 context->type = 0;
1710 context->fds[0] = -1;
1711 if (context->state != AUDIT_RECORD_CONTEXT) {
1712 kfree(context->filterkey);
1713 context->filterkey = NULL;
1714 }
1715 tsk->audit_context = context;
1716 }
1717 }
1718
handle_one(const struct inode * inode)1719 static inline void handle_one(const struct inode *inode)
1720 {
1721 #ifdef CONFIG_AUDIT_TREE
1722 struct audit_context *context;
1723 struct audit_tree_refs *p;
1724 struct audit_chunk *chunk;
1725 int count;
1726 if (likely(list_empty(&inode->inotify_watches)))
1727 return;
1728 context = current->audit_context;
1729 p = context->trees;
1730 count = context->tree_count;
1731 rcu_read_lock();
1732 chunk = audit_tree_lookup(inode);
1733 rcu_read_unlock();
1734 if (!chunk)
1735 return;
1736 if (likely(put_tree_ref(context, chunk)))
1737 return;
1738 if (unlikely(!grow_tree_refs(context))) {
1739 printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
1740 audit_set_auditable(context);
1741 audit_put_chunk(chunk);
1742 unroll_tree_refs(context, p, count);
1743 return;
1744 }
1745 put_tree_ref(context, chunk);
1746 #endif
1747 }
1748
handle_path(const struct dentry * dentry)1749 static void handle_path(const struct dentry *dentry)
1750 {
1751 #ifdef CONFIG_AUDIT_TREE
1752 struct audit_context *context;
1753 struct audit_tree_refs *p;
1754 const struct dentry *d, *parent;
1755 struct audit_chunk *drop;
1756 unsigned long seq;
1757 int count;
1758
1759 context = current->audit_context;
1760 p = context->trees;
1761 count = context->tree_count;
1762 retry:
1763 drop = NULL;
1764 d = dentry;
1765 rcu_read_lock();
1766 seq = read_seqbegin(&rename_lock);
1767 for(;;) {
1768 struct inode *inode = d->d_inode;
1769 if (inode && unlikely(!list_empty(&inode->inotify_watches))) {
1770 struct audit_chunk *chunk;
1771 chunk = audit_tree_lookup(inode);
1772 if (chunk) {
1773 if (unlikely(!put_tree_ref(context, chunk))) {
1774 drop = chunk;
1775 break;
1776 }
1777 }
1778 }
1779 parent = d->d_parent;
1780 if (parent == d)
1781 break;
1782 d = parent;
1783 }
1784 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */
1785 rcu_read_unlock();
1786 if (!drop) {
1787 /* just a race with rename */
1788 unroll_tree_refs(context, p, count);
1789 goto retry;
1790 }
1791 audit_put_chunk(drop);
1792 if (grow_tree_refs(context)) {
1793 /* OK, got more space */
1794 unroll_tree_refs(context, p, count);
1795 goto retry;
1796 }
1797 /* too bad */
1798 printk(KERN_WARNING
1799 "out of memory, audit has lost a tree reference\n");
1800 unroll_tree_refs(context, p, count);
1801 audit_set_auditable(context);
1802 return;
1803 }
1804 rcu_read_unlock();
1805 #endif
1806 }
1807
1808 /**
1809 * audit_getname - add a name to the list
1810 * @name: name to add
1811 *
1812 * Add a name to the list of audit names for this context.
1813 * Called from fs/namei.c:getname().
1814 */
__audit_getname(const char * name)1815 void __audit_getname(const char *name)
1816 {
1817 struct audit_context *context = current->audit_context;
1818
1819 if (IS_ERR(name) || !name)
1820 return;
1821
1822 if (!context->in_syscall) {
1823 #if AUDIT_DEBUG == 2
1824 printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
1825 __FILE__, __LINE__, context->serial, name);
1826 dump_stack();
1827 #endif
1828 return;
1829 }
1830 BUG_ON(context->name_count >= AUDIT_NAMES);
1831 context->names[context->name_count].name = name;
1832 context->names[context->name_count].name_len = AUDIT_NAME_FULL;
1833 context->names[context->name_count].name_put = 1;
1834 context->names[context->name_count].ino = (unsigned long)-1;
1835 context->names[context->name_count].osid = 0;
1836 ++context->name_count;
1837 if (!context->pwd.dentry) {
1838 read_lock(¤t->fs->lock);
1839 context->pwd = current->fs->pwd;
1840 path_get(¤t->fs->pwd);
1841 read_unlock(¤t->fs->lock);
1842 }
1843
1844 }
1845
1846 /* audit_putname - intercept a putname request
1847 * @name: name to intercept and delay for putname
1848 *
1849 * If we have stored the name from getname in the audit context,
1850 * then we delay the putname until syscall exit.
1851 * Called from include/linux/fs.h:putname().
1852 */
audit_putname(const char * name)1853 void audit_putname(const char *name)
1854 {
1855 struct audit_context *context = current->audit_context;
1856
1857 BUG_ON(!context);
1858 if (!context->in_syscall) {
1859 #if AUDIT_DEBUG == 2
1860 printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n",
1861 __FILE__, __LINE__, context->serial, name);
1862 if (context->name_count) {
1863 int i;
1864 for (i = 0; i < context->name_count; i++)
1865 printk(KERN_ERR "name[%d] = %p = %s\n", i,
1866 context->names[i].name,
1867 context->names[i].name ?: "(null)");
1868 }
1869 #endif
1870 __putname(name);
1871 }
1872 #if AUDIT_DEBUG
1873 else {
1874 ++context->put_count;
1875 if (context->put_count > context->name_count) {
1876 printk(KERN_ERR "%s:%d(:%d): major=%d"
1877 " in_syscall=%d putname(%p) name_count=%d"
1878 " put_count=%d\n",
1879 __FILE__, __LINE__,
1880 context->serial, context->major,
1881 context->in_syscall, name, context->name_count,
1882 context->put_count);
1883 dump_stack();
1884 }
1885 }
1886 #endif
1887 }
1888
audit_inc_name_count(struct audit_context * context,const struct inode * inode)1889 static int audit_inc_name_count(struct audit_context *context,
1890 const struct inode *inode)
1891 {
1892 if (context->name_count >= AUDIT_NAMES) {
1893 if (inode)
1894 printk(KERN_DEBUG "name_count maxed, losing inode data: "
1895 "dev=%02x:%02x, inode=%lu\n",
1896 MAJOR(inode->i_sb->s_dev),
1897 MINOR(inode->i_sb->s_dev),
1898 inode->i_ino);
1899
1900 else
1901 printk(KERN_DEBUG "name_count maxed, losing inode data\n");
1902 return 1;
1903 }
1904 context->name_count++;
1905 #if AUDIT_DEBUG
1906 context->ino_count++;
1907 #endif
1908 return 0;
1909 }
1910
1911
audit_copy_fcaps(struct audit_names * name,const struct dentry * dentry)1912 static inline int audit_copy_fcaps(struct audit_names *name, const struct dentry *dentry)
1913 {
1914 struct cpu_vfs_cap_data caps;
1915 int rc;
1916
1917 memset(&name->fcap.permitted, 0, sizeof(kernel_cap_t));
1918 memset(&name->fcap.inheritable, 0, sizeof(kernel_cap_t));
1919 name->fcap.fE = 0;
1920 name->fcap_ver = 0;
1921
1922 if (!dentry)
1923 return 0;
1924
1925 rc = get_vfs_caps_from_disk(dentry, &caps);
1926 if (rc)
1927 return rc;
1928
1929 name->fcap.permitted = caps.permitted;
1930 name->fcap.inheritable = caps.inheritable;
1931 name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
1932 name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
1933
1934 return 0;
1935 }
1936
1937
1938 /* Copy inode data into an audit_names. */
audit_copy_inode(struct audit_names * name,const struct dentry * dentry,const struct inode * inode)1939 static void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
1940 const struct inode *inode)
1941 {
1942 name->ino = inode->i_ino;
1943 name->dev = inode->i_sb->s_dev;
1944 name->mode = inode->i_mode;
1945 name->uid = inode->i_uid;
1946 name->gid = inode->i_gid;
1947 name->rdev = inode->i_rdev;
1948 security_inode_getsecid(inode, &name->osid);
1949 audit_copy_fcaps(name, dentry);
1950 }
1951
1952 /**
1953 * audit_inode - store the inode and device from a lookup
1954 * @name: name being audited
1955 * @dentry: dentry being audited
1956 *
1957 * Called from fs/namei.c:path_lookup().
1958 */
__audit_inode(const char * name,const struct dentry * dentry)1959 void __audit_inode(const char *name, const struct dentry *dentry)
1960 {
1961 int idx;
1962 struct audit_context *context = current->audit_context;
1963 const struct inode *inode = dentry->d_inode;
1964
1965 if (!context->in_syscall)
1966 return;
1967 if (context->name_count
1968 && context->names[context->name_count-1].name
1969 && context->names[context->name_count-1].name == name)
1970 idx = context->name_count - 1;
1971 else if (context->name_count > 1
1972 && context->names[context->name_count-2].name
1973 && context->names[context->name_count-2].name == name)
1974 idx = context->name_count - 2;
1975 else {
1976 /* FIXME: how much do we care about inodes that have no
1977 * associated name? */
1978 if (audit_inc_name_count(context, inode))
1979 return;
1980 idx = context->name_count - 1;
1981 context->names[idx].name = NULL;
1982 }
1983 handle_path(dentry);
1984 audit_copy_inode(&context->names[idx], dentry, inode);
1985 }
1986
1987 /**
1988 * audit_inode_child - collect inode info for created/removed objects
1989 * @dname: inode's dentry name
1990 * @dentry: dentry being audited
1991 * @parent: inode of dentry parent
1992 *
1993 * For syscalls that create or remove filesystem objects, audit_inode
1994 * can only collect information for the filesystem object's parent.
1995 * This call updates the audit context with the child's information.
1996 * Syscalls that create a new filesystem object must be hooked after
1997 * the object is created. Syscalls that remove a filesystem object
1998 * must be hooked prior, in order to capture the target inode during
1999 * unsuccessful attempts.
2000 */
__audit_inode_child(const char * dname,const struct dentry * dentry,const struct inode * parent)2001 void __audit_inode_child(const char *dname, const struct dentry *dentry,
2002 const struct inode *parent)
2003 {
2004 int idx;
2005 struct audit_context *context = current->audit_context;
2006 const char *found_parent = NULL, *found_child = NULL;
2007 const struct inode *inode = dentry->d_inode;
2008 int dirlen = 0;
2009
2010 if (!context->in_syscall)
2011 return;
2012
2013 if (inode)
2014 handle_one(inode);
2015 /* determine matching parent */
2016 if (!dname)
2017 goto add_names;
2018
2019 /* parent is more likely, look for it first */
2020 for (idx = 0; idx < context->name_count; idx++) {
2021 struct audit_names *n = &context->names[idx];
2022
2023 if (!n->name)
2024 continue;
2025
2026 if (n->ino == parent->i_ino &&
2027 !audit_compare_dname_path(dname, n->name, &dirlen)) {
2028 n->name_len = dirlen; /* update parent data in place */
2029 found_parent = n->name;
2030 goto add_names;
2031 }
2032 }
2033
2034 /* no matching parent, look for matching child */
2035 for (idx = 0; idx < context->name_count; idx++) {
2036 struct audit_names *n = &context->names[idx];
2037
2038 if (!n->name)
2039 continue;
2040
2041 /* strcmp() is the more likely scenario */
2042 if (!strcmp(dname, n->name) ||
2043 !audit_compare_dname_path(dname, n->name, &dirlen)) {
2044 if (inode)
2045 audit_copy_inode(n, NULL, inode);
2046 else
2047 n->ino = (unsigned long)-1;
2048 found_child = n->name;
2049 goto add_names;
2050 }
2051 }
2052
2053 add_names:
2054 if (!found_parent) {
2055 if (audit_inc_name_count(context, parent))
2056 return;
2057 idx = context->name_count - 1;
2058 context->names[idx].name = NULL;
2059 audit_copy_inode(&context->names[idx], NULL, parent);
2060 }
2061
2062 if (!found_child) {
2063 if (audit_inc_name_count(context, inode))
2064 return;
2065 idx = context->name_count - 1;
2066
2067 /* Re-use the name belonging to the slot for a matching parent
2068 * directory. All names for this context are relinquished in
2069 * audit_free_names() */
2070 if (found_parent) {
2071 context->names[idx].name = found_parent;
2072 context->names[idx].name_len = AUDIT_NAME_FULL;
2073 /* don't call __putname() */
2074 context->names[idx].name_put = 0;
2075 } else {
2076 context->names[idx].name = NULL;
2077 }
2078
2079 if (inode)
2080 audit_copy_inode(&context->names[idx], NULL, inode);
2081 else
2082 context->names[idx].ino = (unsigned long)-1;
2083 }
2084 }
2085 EXPORT_SYMBOL_GPL(__audit_inode_child);
2086
2087 /**
2088 * auditsc_get_stamp - get local copies of audit_context values
2089 * @ctx: audit_context for the task
2090 * @t: timespec to store time recorded in the audit_context
2091 * @serial: serial value that is recorded in the audit_context
2092 *
2093 * Also sets the context as auditable.
2094 */
auditsc_get_stamp(struct audit_context * ctx,struct timespec * t,unsigned int * serial)2095 int auditsc_get_stamp(struct audit_context *ctx,
2096 struct timespec *t, unsigned int *serial)
2097 {
2098 if (!ctx->in_syscall)
2099 return 0;
2100 if (!ctx->serial)
2101 ctx->serial = audit_serial();
2102 t->tv_sec = ctx->ctime.tv_sec;
2103 t->tv_nsec = ctx->ctime.tv_nsec;
2104 *serial = ctx->serial;
2105 if (!ctx->prio) {
2106 ctx->prio = 1;
2107 ctx->current_state = AUDIT_RECORD_CONTEXT;
2108 }
2109 return 1;
2110 }
2111
2112 /* global counter which is incremented every time something logs in */
2113 static atomic_t session_id = ATOMIC_INIT(0);
2114
2115 /**
2116 * audit_set_loginuid - set a task's audit_context loginuid
2117 * @task: task whose audit context is being modified
2118 * @loginuid: loginuid value
2119 *
2120 * Returns 0.
2121 *
2122 * Called (set) from fs/proc/base.c::proc_loginuid_write().
2123 */
audit_set_loginuid(struct task_struct * task,uid_t loginuid)2124 int audit_set_loginuid(struct task_struct *task, uid_t loginuid)
2125 {
2126 unsigned int sessionid = atomic_inc_return(&session_id);
2127 struct audit_context *context = task->audit_context;
2128
2129 if (context && context->in_syscall) {
2130 struct audit_buffer *ab;
2131
2132 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
2133 if (ab) {
2134 audit_log_format(ab, "login pid=%d uid=%u "
2135 "old auid=%u new auid=%u"
2136 " old ses=%u new ses=%u",
2137 task->pid, task_uid(task),
2138 task->loginuid, loginuid,
2139 task->sessionid, sessionid);
2140 audit_log_end(ab);
2141 }
2142 }
2143 task->sessionid = sessionid;
2144 task->loginuid = loginuid;
2145 return 0;
2146 }
2147
2148 /**
2149 * __audit_mq_open - record audit data for a POSIX MQ open
2150 * @oflag: open flag
2151 * @mode: mode bits
2152 * @u_attr: queue attributes
2153 *
2154 */
__audit_mq_open(int oflag,mode_t mode,struct mq_attr * attr)2155 void __audit_mq_open(int oflag, mode_t mode, struct mq_attr *attr)
2156 {
2157 struct audit_context *context = current->audit_context;
2158
2159 if (attr)
2160 memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
2161 else
2162 memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2163
2164 context->mq_open.oflag = oflag;
2165 context->mq_open.mode = mode;
2166
2167 context->type = AUDIT_MQ_OPEN;
2168 }
2169
2170 /**
2171 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2172 * @mqdes: MQ descriptor
2173 * @msg_len: Message length
2174 * @msg_prio: Message priority
2175 * @abs_timeout: Message timeout in absolute time
2176 *
2177 */
__audit_mq_sendrecv(mqd_t mqdes,size_t msg_len,unsigned int msg_prio,const struct timespec * abs_timeout)2178 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2179 const struct timespec *abs_timeout)
2180 {
2181 struct audit_context *context = current->audit_context;
2182 struct timespec *p = &context->mq_sendrecv.abs_timeout;
2183
2184 if (abs_timeout)
2185 memcpy(p, abs_timeout, sizeof(struct timespec));
2186 else
2187 memset(p, 0, sizeof(struct timespec));
2188
2189 context->mq_sendrecv.mqdes = mqdes;
2190 context->mq_sendrecv.msg_len = msg_len;
2191 context->mq_sendrecv.msg_prio = msg_prio;
2192
2193 context->type = AUDIT_MQ_SENDRECV;
2194 }
2195
2196 /**
2197 * __audit_mq_notify - record audit data for a POSIX MQ notify
2198 * @mqdes: MQ descriptor
2199 * @u_notification: Notification event
2200 *
2201 */
2202
__audit_mq_notify(mqd_t mqdes,const struct sigevent * notification)2203 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2204 {
2205 struct audit_context *context = current->audit_context;
2206
2207 if (notification)
2208 context->mq_notify.sigev_signo = notification->sigev_signo;
2209 else
2210 context->mq_notify.sigev_signo = 0;
2211
2212 context->mq_notify.mqdes = mqdes;
2213 context->type = AUDIT_MQ_NOTIFY;
2214 }
2215
2216 /**
2217 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2218 * @mqdes: MQ descriptor
2219 * @mqstat: MQ flags
2220 *
2221 */
__audit_mq_getsetattr(mqd_t mqdes,struct mq_attr * mqstat)2222 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2223 {
2224 struct audit_context *context = current->audit_context;
2225 context->mq_getsetattr.mqdes = mqdes;
2226 context->mq_getsetattr.mqstat = *mqstat;
2227 context->type = AUDIT_MQ_GETSETATTR;
2228 }
2229
2230 /**
2231 * audit_ipc_obj - record audit data for ipc object
2232 * @ipcp: ipc permissions
2233 *
2234 */
__audit_ipc_obj(struct kern_ipc_perm * ipcp)2235 void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2236 {
2237 struct audit_context *context = current->audit_context;
2238 context->ipc.uid = ipcp->uid;
2239 context->ipc.gid = ipcp->gid;
2240 context->ipc.mode = ipcp->mode;
2241 context->ipc.has_perm = 0;
2242 security_ipc_getsecid(ipcp, &context->ipc.osid);
2243 context->type = AUDIT_IPC;
2244 }
2245
2246 /**
2247 * audit_ipc_set_perm - record audit data for new ipc permissions
2248 * @qbytes: msgq bytes
2249 * @uid: msgq user id
2250 * @gid: msgq group id
2251 * @mode: msgq mode (permissions)
2252 *
2253 * Called only after audit_ipc_obj().
2254 */
__audit_ipc_set_perm(unsigned long qbytes,uid_t uid,gid_t gid,mode_t mode)2255 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode)
2256 {
2257 struct audit_context *context = current->audit_context;
2258
2259 context->ipc.qbytes = qbytes;
2260 context->ipc.perm_uid = uid;
2261 context->ipc.perm_gid = gid;
2262 context->ipc.perm_mode = mode;
2263 context->ipc.has_perm = 1;
2264 }
2265
audit_bprm(struct linux_binprm * bprm)2266 int audit_bprm(struct linux_binprm *bprm)
2267 {
2268 struct audit_aux_data_execve *ax;
2269 struct audit_context *context = current->audit_context;
2270
2271 if (likely(!audit_enabled || !context || context->dummy))
2272 return 0;
2273
2274 ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2275 if (!ax)
2276 return -ENOMEM;
2277
2278 ax->argc = bprm->argc;
2279 ax->envc = bprm->envc;
2280 ax->mm = bprm->mm;
2281 ax->d.type = AUDIT_EXECVE;
2282 ax->d.next = context->aux;
2283 context->aux = (void *)ax;
2284 return 0;
2285 }
2286
2287
2288 /**
2289 * audit_socketcall - record audit data for sys_socketcall
2290 * @nargs: number of args
2291 * @args: args array
2292 *
2293 */
audit_socketcall(int nargs,unsigned long * args)2294 void audit_socketcall(int nargs, unsigned long *args)
2295 {
2296 struct audit_context *context = current->audit_context;
2297
2298 if (likely(!context || context->dummy))
2299 return;
2300
2301 context->type = AUDIT_SOCKETCALL;
2302 context->socketcall.nargs = nargs;
2303 memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
2304 }
2305
2306 /**
2307 * __audit_fd_pair - record audit data for pipe and socketpair
2308 * @fd1: the first file descriptor
2309 * @fd2: the second file descriptor
2310 *
2311 */
__audit_fd_pair(int fd1,int fd2)2312 void __audit_fd_pair(int fd1, int fd2)
2313 {
2314 struct audit_context *context = current->audit_context;
2315 context->fds[0] = fd1;
2316 context->fds[1] = fd2;
2317 }
2318
2319 /**
2320 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2321 * @len: data length in user space
2322 * @a: data address in kernel space
2323 *
2324 * Returns 0 for success or NULL context or < 0 on error.
2325 */
audit_sockaddr(int len,void * a)2326 int audit_sockaddr(int len, void *a)
2327 {
2328 struct audit_context *context = current->audit_context;
2329
2330 if (likely(!context || context->dummy))
2331 return 0;
2332
2333 if (!context->sockaddr) {
2334 void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
2335 if (!p)
2336 return -ENOMEM;
2337 context->sockaddr = p;
2338 }
2339
2340 context->sockaddr_len = len;
2341 memcpy(context->sockaddr, a, len);
2342 return 0;
2343 }
2344
__audit_ptrace(struct task_struct * t)2345 void __audit_ptrace(struct task_struct *t)
2346 {
2347 struct audit_context *context = current->audit_context;
2348
2349 context->target_pid = t->pid;
2350 context->target_auid = audit_get_loginuid(t);
2351 context->target_uid = task_uid(t);
2352 context->target_sessionid = audit_get_sessionid(t);
2353 security_task_getsecid(t, &context->target_sid);
2354 memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
2355 }
2356
2357 /**
2358 * audit_signal_info - record signal info for shutting down audit subsystem
2359 * @sig: signal value
2360 * @t: task being signaled
2361 *
2362 * If the audit subsystem is being terminated, record the task (pid)
2363 * and uid that is doing that.
2364 */
__audit_signal_info(int sig,struct task_struct * t)2365 int __audit_signal_info(int sig, struct task_struct *t)
2366 {
2367 struct audit_aux_data_pids *axp;
2368 struct task_struct *tsk = current;
2369 struct audit_context *ctx = tsk->audit_context;
2370 uid_t uid = current_uid(), t_uid = task_uid(t);
2371
2372 if (audit_pid && t->tgid == audit_pid) {
2373 if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
2374 audit_sig_pid = tsk->pid;
2375 if (tsk->loginuid != -1)
2376 audit_sig_uid = tsk->loginuid;
2377 else
2378 audit_sig_uid = uid;
2379 security_task_getsecid(tsk, &audit_sig_sid);
2380 }
2381 if (!audit_signals || audit_dummy_context())
2382 return 0;
2383 }
2384
2385 /* optimize the common case by putting first signal recipient directly
2386 * in audit_context */
2387 if (!ctx->target_pid) {
2388 ctx->target_pid = t->tgid;
2389 ctx->target_auid = audit_get_loginuid(t);
2390 ctx->target_uid = t_uid;
2391 ctx->target_sessionid = audit_get_sessionid(t);
2392 security_task_getsecid(t, &ctx->target_sid);
2393 memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
2394 return 0;
2395 }
2396
2397 axp = (void *)ctx->aux_pids;
2398 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2399 axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2400 if (!axp)
2401 return -ENOMEM;
2402
2403 axp->d.type = AUDIT_OBJ_PID;
2404 axp->d.next = ctx->aux_pids;
2405 ctx->aux_pids = (void *)axp;
2406 }
2407 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2408
2409 axp->target_pid[axp->pid_count] = t->tgid;
2410 axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2411 axp->target_uid[axp->pid_count] = t_uid;
2412 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2413 security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2414 memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
2415 axp->pid_count++;
2416
2417 return 0;
2418 }
2419
2420 /**
2421 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
2422 * @bprm: pointer to the bprm being processed
2423 * @new: the proposed new credentials
2424 * @old: the old credentials
2425 *
2426 * Simply check if the proc already has the caps given by the file and if not
2427 * store the priv escalation info for later auditing at the end of the syscall
2428 *
2429 * -Eric
2430 */
__audit_log_bprm_fcaps(struct linux_binprm * bprm,const struct cred * new,const struct cred * old)2431 int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
2432 const struct cred *new, const struct cred *old)
2433 {
2434 struct audit_aux_data_bprm_fcaps *ax;
2435 struct audit_context *context = current->audit_context;
2436 struct cpu_vfs_cap_data vcaps;
2437 struct dentry *dentry;
2438
2439 ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2440 if (!ax)
2441 return -ENOMEM;
2442
2443 ax->d.type = AUDIT_BPRM_FCAPS;
2444 ax->d.next = context->aux;
2445 context->aux = (void *)ax;
2446
2447 dentry = dget(bprm->file->f_dentry);
2448 get_vfs_caps_from_disk(dentry, &vcaps);
2449 dput(dentry);
2450
2451 ax->fcap.permitted = vcaps.permitted;
2452 ax->fcap.inheritable = vcaps.inheritable;
2453 ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2454 ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
2455
2456 ax->old_pcap.permitted = old->cap_permitted;
2457 ax->old_pcap.inheritable = old->cap_inheritable;
2458 ax->old_pcap.effective = old->cap_effective;
2459
2460 ax->new_pcap.permitted = new->cap_permitted;
2461 ax->new_pcap.inheritable = new->cap_inheritable;
2462 ax->new_pcap.effective = new->cap_effective;
2463 return 0;
2464 }
2465
2466 /**
2467 * __audit_log_capset - store information about the arguments to the capset syscall
2468 * @pid: target pid of the capset call
2469 * @new: the new credentials
2470 * @old: the old (current) credentials
2471 *
2472 * Record the aguments userspace sent to sys_capset for later printing by the
2473 * audit system if applicable
2474 */
__audit_log_capset(pid_t pid,const struct cred * new,const struct cred * old)2475 void __audit_log_capset(pid_t pid,
2476 const struct cred *new, const struct cred *old)
2477 {
2478 struct audit_context *context = current->audit_context;
2479 context->capset.pid = pid;
2480 context->capset.cap.effective = new->cap_effective;
2481 context->capset.cap.inheritable = new->cap_effective;
2482 context->capset.cap.permitted = new->cap_permitted;
2483 context->type = AUDIT_CAPSET;
2484 }
2485
2486 /**
2487 * audit_core_dumps - record information about processes that end abnormally
2488 * @signr: signal value
2489 *
2490 * If a process ends with a core dump, something fishy is going on and we
2491 * should record the event for investigation.
2492 */
audit_core_dumps(long signr)2493 void audit_core_dumps(long signr)
2494 {
2495 struct audit_buffer *ab;
2496 u32 sid;
2497 uid_t auid = audit_get_loginuid(current), uid;
2498 gid_t gid;
2499 unsigned int sessionid = audit_get_sessionid(current);
2500
2501 if (!audit_enabled)
2502 return;
2503
2504 if (signr == SIGQUIT) /* don't care for those */
2505 return;
2506
2507 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2508 current_uid_gid(&uid, &gid);
2509 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2510 auid, uid, gid, sessionid);
2511 security_task_getsecid(current, &sid);
2512 if (sid) {
2513 char *ctx = NULL;
2514 u32 len;
2515
2516 if (security_secid_to_secctx(sid, &ctx, &len))
2517 audit_log_format(ab, " ssid=%u", sid);
2518 else {
2519 audit_log_format(ab, " subj=%s", ctx);
2520 security_release_secctx(ctx, len);
2521 }
2522 }
2523 audit_log_format(ab, " pid=%d comm=", current->pid);
2524 audit_log_untrustedstring(ab, current->comm);
2525 audit_log_format(ab, " sig=%ld", signr);
2526 audit_log_end(ab);
2527 }
2528