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