xref: /linux/kernel/auditsc.c (revision f7511d5f66f01fc451747b24e79f3ada7a3af9af)
1 /* auditsc.c -- System-call auditing support
2  * Handles all system-call specific auditing features.
3  *
4  * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
5  * Copyright 2005 Hewlett-Packard Development Company, L.P.
6  * Copyright (C) 2005, 2006 IBM Corporation
7  * All Rights Reserved.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
22  *
23  * Written by Rickard E. (Rik) Faith <faith@redhat.com>
24  *
25  * Many of the ideas implemented here are from Stephen C. Tweedie,
26  * especially the idea of avoiding a copy by using getname.
27  *
28  * The method for actual interception of syscall entry and exit (not in
29  * this file -- see entry.S) is based on a GPL'd patch written by
30  * okir@suse.de and Copyright 2003 SuSE Linux AG.
31  *
32  * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>,
33  * 2006.
34  *
35  * The support of additional filter rules compares (>, <, >=, <=) was
36  * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005.
37  *
38  * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional
39  * filesystem information.
40  *
41  * Subject and object context labeling support added by <danjones@us.ibm.com>
42  * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance.
43  */
44 
45 #include <linux/init.h>
46 #include <asm/types.h>
47 #include <asm/atomic.h>
48 #include <linux/fs.h>
49 #include <linux/namei.h>
50 #include <linux/mm.h>
51 #include <linux/module.h>
52 #include <linux/mount.h>
53 #include <linux/socket.h>
54 #include <linux/mqueue.h>
55 #include <linux/audit.h>
56 #include <linux/personality.h>
57 #include <linux/time.h>
58 #include <linux/netlink.h>
59 #include <linux/compiler.h>
60 #include <asm/unistd.h>
61 #include <linux/security.h>
62 #include <linux/list.h>
63 #include <linux/tty.h>
64 #include <linux/binfmts.h>
65 #include <linux/highmem.h>
66 #include <linux/syscalls.h>
67 #include <linux/inotify.h>
68 
69 #include "audit.h"
70 
71 /* AUDIT_NAMES is the number of slots we reserve in the audit_context
72  * for saving names from getname(). */
73 #define AUDIT_NAMES    20
74 
75 /* Indicates that audit should log the full pathname. */
76 #define AUDIT_NAME_FULL -1
77 
78 /* no execve audit message should be longer than this (userspace limits) */
79 #define MAX_EXECVE_AUDIT_LEN 7500
80 
81 /* number of audit rules */
82 int audit_n_rules;
83 
84 /* determines whether we collect data for signals sent */
85 int audit_signals;
86 
87 /* When fs/namei.c:getname() is called, we store the pointer in name and
88  * we don't let putname() free it (instead we free all of the saved
89  * pointers at syscall exit time).
90  *
91  * Further, in fs/namei.c:path_lookup() we store the inode and device. */
92 struct audit_names {
93 	const char	*name;
94 	int		name_len;	/* number of name's characters to log */
95 	unsigned	name_put;	/* call __putname() for this name */
96 	unsigned long	ino;
97 	dev_t		dev;
98 	umode_t		mode;
99 	uid_t		uid;
100 	gid_t		gid;
101 	dev_t		rdev;
102 	u32		osid;
103 };
104 
105 struct audit_aux_data {
106 	struct audit_aux_data	*next;
107 	int			type;
108 };
109 
110 #define AUDIT_AUX_IPCPERM	0
111 
112 /* Number of target pids per aux struct. */
113 #define AUDIT_AUX_PIDS	16
114 
115 struct audit_aux_data_mq_open {
116 	struct audit_aux_data	d;
117 	int			oflag;
118 	mode_t			mode;
119 	struct mq_attr		attr;
120 };
121 
122 struct audit_aux_data_mq_sendrecv {
123 	struct audit_aux_data	d;
124 	mqd_t			mqdes;
125 	size_t			msg_len;
126 	unsigned int		msg_prio;
127 	struct timespec		abs_timeout;
128 };
129 
130 struct audit_aux_data_mq_notify {
131 	struct audit_aux_data	d;
132 	mqd_t			mqdes;
133 	struct sigevent 	notification;
134 };
135 
136 struct audit_aux_data_mq_getsetattr {
137 	struct audit_aux_data	d;
138 	mqd_t			mqdes;
139 	struct mq_attr 		mqstat;
140 };
141 
142 struct audit_aux_data_ipcctl {
143 	struct audit_aux_data	d;
144 	struct ipc_perm		p;
145 	unsigned long		qbytes;
146 	uid_t			uid;
147 	gid_t			gid;
148 	mode_t			mode;
149 	u32			osid;
150 };
151 
152 struct audit_aux_data_execve {
153 	struct audit_aux_data	d;
154 	int argc;
155 	int envc;
156 	struct mm_struct *mm;
157 };
158 
159 struct audit_aux_data_socketcall {
160 	struct audit_aux_data	d;
161 	int			nargs;
162 	unsigned long		args[0];
163 };
164 
165 struct audit_aux_data_sockaddr {
166 	struct audit_aux_data	d;
167 	int			len;
168 	char			a[0];
169 };
170 
171 struct audit_aux_data_fd_pair {
172 	struct	audit_aux_data d;
173 	int	fd[2];
174 };
175 
176 struct audit_aux_data_pids {
177 	struct audit_aux_data	d;
178 	pid_t			target_pid[AUDIT_AUX_PIDS];
179 	uid_t			target_auid[AUDIT_AUX_PIDS];
180 	uid_t			target_uid[AUDIT_AUX_PIDS];
181 	unsigned int		target_sessionid[AUDIT_AUX_PIDS];
182 	u32			target_sid[AUDIT_AUX_PIDS];
183 	char 			target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
184 	int			pid_count;
185 };
186 
187 struct audit_tree_refs {
188 	struct audit_tree_refs *next;
189 	struct audit_chunk *c[31];
190 };
191 
192 /* The per-task audit context. */
193 struct audit_context {
194 	int		    dummy;	/* must be the first element */
195 	int		    in_syscall;	/* 1 if task is in a syscall */
196 	enum audit_state    state;
197 	unsigned int	    serial;     /* serial number for record */
198 	struct timespec	    ctime;      /* time of syscall entry */
199 	int		    major;      /* syscall number */
200 	unsigned long	    argv[4];    /* syscall arguments */
201 	int		    return_valid; /* return code is valid */
202 	long		    return_code;/* syscall return code */
203 	int		    auditable;  /* 1 if record should be written */
204 	int		    name_count;
205 	struct audit_names  names[AUDIT_NAMES];
206 	char *		    filterkey;	/* key for rule that triggered record */
207 	struct path	    pwd;
208 	struct audit_context *previous; /* For nested syscalls */
209 	struct audit_aux_data *aux;
210 	struct audit_aux_data *aux_pids;
211 
212 				/* Save things to print about task_struct */
213 	pid_t		    pid, ppid;
214 	uid_t		    uid, euid, suid, fsuid;
215 	gid_t		    gid, egid, sgid, fsgid;
216 	unsigned long	    personality;
217 	int		    arch;
218 
219 	pid_t		    target_pid;
220 	uid_t		    target_auid;
221 	uid_t		    target_uid;
222 	unsigned int	    target_sessionid;
223 	u32		    target_sid;
224 	char		    target_comm[TASK_COMM_LEN];
225 
226 	struct audit_tree_refs *trees, *first_trees;
227 	int tree_count;
228 
229 #if AUDIT_DEBUG
230 	int		    put_count;
231 	int		    ino_count;
232 #endif
233 };
234 
235 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
236 static inline int open_arg(int flags, int mask)
237 {
238 	int n = ACC_MODE(flags);
239 	if (flags & (O_TRUNC | O_CREAT))
240 		n |= AUDIT_PERM_WRITE;
241 	return n & mask;
242 }
243 
244 static int audit_match_perm(struct audit_context *ctx, int mask)
245 {
246 	unsigned n = ctx->major;
247 	switch (audit_classify_syscall(ctx->arch, n)) {
248 	case 0:	/* native */
249 		if ((mask & AUDIT_PERM_WRITE) &&
250 		     audit_match_class(AUDIT_CLASS_WRITE, n))
251 			return 1;
252 		if ((mask & AUDIT_PERM_READ) &&
253 		     audit_match_class(AUDIT_CLASS_READ, n))
254 			return 1;
255 		if ((mask & AUDIT_PERM_ATTR) &&
256 		     audit_match_class(AUDIT_CLASS_CHATTR, n))
257 			return 1;
258 		return 0;
259 	case 1: /* 32bit on biarch */
260 		if ((mask & AUDIT_PERM_WRITE) &&
261 		     audit_match_class(AUDIT_CLASS_WRITE_32, n))
262 			return 1;
263 		if ((mask & AUDIT_PERM_READ) &&
264 		     audit_match_class(AUDIT_CLASS_READ_32, n))
265 			return 1;
266 		if ((mask & AUDIT_PERM_ATTR) &&
267 		     audit_match_class(AUDIT_CLASS_CHATTR_32, n))
268 			return 1;
269 		return 0;
270 	case 2: /* open */
271 		return mask & ACC_MODE(ctx->argv[1]);
272 	case 3: /* openat */
273 		return mask & ACC_MODE(ctx->argv[2]);
274 	case 4: /* socketcall */
275 		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
276 	case 5: /* execve */
277 		return mask & AUDIT_PERM_EXEC;
278 	default:
279 		return 0;
280 	}
281 }
282 
283 static int audit_match_filetype(struct audit_context *ctx, int which)
284 {
285 	unsigned index = which & ~S_IFMT;
286 	mode_t mode = which & S_IFMT;
287 	if (index >= ctx->name_count)
288 		return 0;
289 	if (ctx->names[index].ino == -1)
290 		return 0;
291 	if ((ctx->names[index].mode ^ mode) & S_IFMT)
292 		return 0;
293 	return 1;
294 }
295 
296 /*
297  * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
298  * ->first_trees points to its beginning, ->trees - to the current end of data.
299  * ->tree_count is the number of free entries in array pointed to by ->trees.
300  * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
301  * "empty" becomes (p, p, 31) afterwards.  We don't shrink the list (and seriously,
302  * it's going to remain 1-element for almost any setup) until we free context itself.
303  * References in it _are_ dropped - at the same time we free/drop aux stuff.
304  */
305 
306 #ifdef CONFIG_AUDIT_TREE
307 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
308 {
309 	struct audit_tree_refs *p = ctx->trees;
310 	int left = ctx->tree_count;
311 	if (likely(left)) {
312 		p->c[--left] = chunk;
313 		ctx->tree_count = left;
314 		return 1;
315 	}
316 	if (!p)
317 		return 0;
318 	p = p->next;
319 	if (p) {
320 		p->c[30] = chunk;
321 		ctx->trees = p;
322 		ctx->tree_count = 30;
323 		return 1;
324 	}
325 	return 0;
326 }
327 
328 static int grow_tree_refs(struct audit_context *ctx)
329 {
330 	struct audit_tree_refs *p = ctx->trees;
331 	ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
332 	if (!ctx->trees) {
333 		ctx->trees = p;
334 		return 0;
335 	}
336 	if (p)
337 		p->next = ctx->trees;
338 	else
339 		ctx->first_trees = ctx->trees;
340 	ctx->tree_count = 31;
341 	return 1;
342 }
343 #endif
344 
345 static void unroll_tree_refs(struct audit_context *ctx,
346 		      struct audit_tree_refs *p, int count)
347 {
348 #ifdef CONFIG_AUDIT_TREE
349 	struct audit_tree_refs *q;
350 	int n;
351 	if (!p) {
352 		/* we started with empty chain */
353 		p = ctx->first_trees;
354 		count = 31;
355 		/* if the very first allocation has failed, nothing to do */
356 		if (!p)
357 			return;
358 	}
359 	n = count;
360 	for (q = p; q != ctx->trees; q = q->next, n = 31) {
361 		while (n--) {
362 			audit_put_chunk(q->c[n]);
363 			q->c[n] = NULL;
364 		}
365 	}
366 	while (n-- > ctx->tree_count) {
367 		audit_put_chunk(q->c[n]);
368 		q->c[n] = NULL;
369 	}
370 	ctx->trees = p;
371 	ctx->tree_count = count;
372 #endif
373 }
374 
375 static void free_tree_refs(struct audit_context *ctx)
376 {
377 	struct audit_tree_refs *p, *q;
378 	for (p = ctx->first_trees; p; p = q) {
379 		q = p->next;
380 		kfree(p);
381 	}
382 }
383 
384 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
385 {
386 #ifdef CONFIG_AUDIT_TREE
387 	struct audit_tree_refs *p;
388 	int n;
389 	if (!tree)
390 		return 0;
391 	/* full ones */
392 	for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
393 		for (n = 0; n < 31; n++)
394 			if (audit_tree_match(p->c[n], tree))
395 				return 1;
396 	}
397 	/* partial */
398 	if (p) {
399 		for (n = ctx->tree_count; n < 31; n++)
400 			if (audit_tree_match(p->c[n], tree))
401 				return 1;
402 	}
403 #endif
404 	return 0;
405 }
406 
407 /* Determine if any context name data matches a rule's watch data */
408 /* Compare a task_struct with an audit_rule.  Return 1 on match, 0
409  * otherwise. */
410 static int audit_filter_rules(struct task_struct *tsk,
411 			      struct audit_krule *rule,
412 			      struct audit_context *ctx,
413 			      struct audit_names *name,
414 			      enum audit_state *state)
415 {
416 	int i, j, need_sid = 1;
417 	u32 sid;
418 
419 	for (i = 0; i < rule->field_count; i++) {
420 		struct audit_field *f = &rule->fields[i];
421 		int result = 0;
422 
423 		switch (f->type) {
424 		case AUDIT_PID:
425 			result = audit_comparator(tsk->pid, f->op, f->val);
426 			break;
427 		case AUDIT_PPID:
428 			if (ctx) {
429 				if (!ctx->ppid)
430 					ctx->ppid = sys_getppid();
431 				result = audit_comparator(ctx->ppid, f->op, f->val);
432 			}
433 			break;
434 		case AUDIT_UID:
435 			result = audit_comparator(tsk->uid, f->op, f->val);
436 			break;
437 		case AUDIT_EUID:
438 			result = audit_comparator(tsk->euid, f->op, f->val);
439 			break;
440 		case AUDIT_SUID:
441 			result = audit_comparator(tsk->suid, f->op, f->val);
442 			break;
443 		case AUDIT_FSUID:
444 			result = audit_comparator(tsk->fsuid, f->op, f->val);
445 			break;
446 		case AUDIT_GID:
447 			result = audit_comparator(tsk->gid, f->op, f->val);
448 			break;
449 		case AUDIT_EGID:
450 			result = audit_comparator(tsk->egid, f->op, f->val);
451 			break;
452 		case AUDIT_SGID:
453 			result = audit_comparator(tsk->sgid, f->op, f->val);
454 			break;
455 		case AUDIT_FSGID:
456 			result = audit_comparator(tsk->fsgid, f->op, f->val);
457 			break;
458 		case AUDIT_PERS:
459 			result = audit_comparator(tsk->personality, f->op, f->val);
460 			break;
461 		case AUDIT_ARCH:
462 			if (ctx)
463 				result = audit_comparator(ctx->arch, f->op, f->val);
464 			break;
465 
466 		case AUDIT_EXIT:
467 			if (ctx && ctx->return_valid)
468 				result = audit_comparator(ctx->return_code, f->op, f->val);
469 			break;
470 		case AUDIT_SUCCESS:
471 			if (ctx && ctx->return_valid) {
472 				if (f->val)
473 					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
474 				else
475 					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
476 			}
477 			break;
478 		case AUDIT_DEVMAJOR:
479 			if (name)
480 				result = audit_comparator(MAJOR(name->dev),
481 							  f->op, f->val);
482 			else if (ctx) {
483 				for (j = 0; j < ctx->name_count; j++) {
484 					if (audit_comparator(MAJOR(ctx->names[j].dev),	f->op, f->val)) {
485 						++result;
486 						break;
487 					}
488 				}
489 			}
490 			break;
491 		case AUDIT_DEVMINOR:
492 			if (name)
493 				result = audit_comparator(MINOR(name->dev),
494 							  f->op, f->val);
495 			else if (ctx) {
496 				for (j = 0; j < ctx->name_count; j++) {
497 					if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) {
498 						++result;
499 						break;
500 					}
501 				}
502 			}
503 			break;
504 		case AUDIT_INODE:
505 			if (name)
506 				result = (name->ino == f->val);
507 			else if (ctx) {
508 				for (j = 0; j < ctx->name_count; j++) {
509 					if (audit_comparator(ctx->names[j].ino, f->op, f->val)) {
510 						++result;
511 						break;
512 					}
513 				}
514 			}
515 			break;
516 		case AUDIT_WATCH:
517 			if (name && rule->watch->ino != (unsigned long)-1)
518 				result = (name->dev == rule->watch->dev &&
519 					  name->ino == rule->watch->ino);
520 			break;
521 		case AUDIT_DIR:
522 			if (ctx)
523 				result = match_tree_refs(ctx, rule->tree);
524 			break;
525 		case AUDIT_LOGINUID:
526 			result = 0;
527 			if (ctx)
528 				result = audit_comparator(tsk->loginuid, f->op, f->val);
529 			break;
530 		case AUDIT_SUBJ_USER:
531 		case AUDIT_SUBJ_ROLE:
532 		case AUDIT_SUBJ_TYPE:
533 		case AUDIT_SUBJ_SEN:
534 		case AUDIT_SUBJ_CLR:
535 			/* NOTE: this may return negative values indicating
536 			   a temporary error.  We simply treat this as a
537 			   match for now to avoid losing information that
538 			   may be wanted.   An error message will also be
539 			   logged upon error */
540 			if (f->lsm_rule) {
541 				if (need_sid) {
542 					security_task_getsecid(tsk, &sid);
543 					need_sid = 0;
544 				}
545 				result = security_audit_rule_match(sid, f->type,
546 				                                  f->op,
547 				                                  f->lsm_rule,
548 				                                  ctx);
549 			}
550 			break;
551 		case AUDIT_OBJ_USER:
552 		case AUDIT_OBJ_ROLE:
553 		case AUDIT_OBJ_TYPE:
554 		case AUDIT_OBJ_LEV_LOW:
555 		case AUDIT_OBJ_LEV_HIGH:
556 			/* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
557 			   also applies here */
558 			if (f->lsm_rule) {
559 				/* Find files that match */
560 				if (name) {
561 					result = security_audit_rule_match(
562 					           name->osid, f->type, f->op,
563 					           f->lsm_rule, ctx);
564 				} else if (ctx) {
565 					for (j = 0; j < ctx->name_count; j++) {
566 						if (security_audit_rule_match(
567 						      ctx->names[j].osid,
568 						      f->type, f->op,
569 						      f->lsm_rule, ctx)) {
570 							++result;
571 							break;
572 						}
573 					}
574 				}
575 				/* Find ipc objects that match */
576 				if (ctx) {
577 					struct audit_aux_data *aux;
578 					for (aux = ctx->aux; aux;
579 					     aux = aux->next) {
580 						if (aux->type == AUDIT_IPC) {
581 							struct audit_aux_data_ipcctl *axi = (void *)aux;
582 							if (security_audit_rule_match(axi->osid, f->type, f->op, f->lsm_rule, ctx)) {
583 								++result;
584 								break;
585 							}
586 						}
587 					}
588 				}
589 			}
590 			break;
591 		case AUDIT_ARG0:
592 		case AUDIT_ARG1:
593 		case AUDIT_ARG2:
594 		case AUDIT_ARG3:
595 			if (ctx)
596 				result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
597 			break;
598 		case AUDIT_FILTERKEY:
599 			/* ignore this field for filtering */
600 			result = 1;
601 			break;
602 		case AUDIT_PERM:
603 			result = audit_match_perm(ctx, f->val);
604 			break;
605 		case AUDIT_FILETYPE:
606 			result = audit_match_filetype(ctx, f->val);
607 			break;
608 		}
609 
610 		if (!result)
611 			return 0;
612 	}
613 	if (rule->filterkey)
614 		ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
615 	switch (rule->action) {
616 	case AUDIT_NEVER:    *state = AUDIT_DISABLED;	    break;
617 	case AUDIT_ALWAYS:   *state = AUDIT_RECORD_CONTEXT; break;
618 	}
619 	return 1;
620 }
621 
622 /* At process creation time, we can determine if system-call auditing is
623  * completely disabled for this task.  Since we only have the task
624  * structure at this point, we can only check uid and gid.
625  */
626 static enum audit_state audit_filter_task(struct task_struct *tsk)
627 {
628 	struct audit_entry *e;
629 	enum audit_state   state;
630 
631 	rcu_read_lock();
632 	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
633 		if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) {
634 			rcu_read_unlock();
635 			return state;
636 		}
637 	}
638 	rcu_read_unlock();
639 	return AUDIT_BUILD_CONTEXT;
640 }
641 
642 /* At syscall entry and exit time, this filter is called if the
643  * audit_state is not low enough that auditing cannot take place, but is
644  * also not high enough that we already know we have to write an audit
645  * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
646  */
647 static enum audit_state audit_filter_syscall(struct task_struct *tsk,
648 					     struct audit_context *ctx,
649 					     struct list_head *list)
650 {
651 	struct audit_entry *e;
652 	enum audit_state state;
653 
654 	if (audit_pid && tsk->tgid == audit_pid)
655 		return AUDIT_DISABLED;
656 
657 	rcu_read_lock();
658 	if (!list_empty(list)) {
659 		int word = AUDIT_WORD(ctx->major);
660 		int bit  = AUDIT_BIT(ctx->major);
661 
662 		list_for_each_entry_rcu(e, list, list) {
663 			if ((e->rule.mask[word] & bit) == bit &&
664 			    audit_filter_rules(tsk, &e->rule, ctx, NULL,
665 					       &state)) {
666 				rcu_read_unlock();
667 				return state;
668 			}
669 		}
670 	}
671 	rcu_read_unlock();
672 	return AUDIT_BUILD_CONTEXT;
673 }
674 
675 /* At syscall exit time, this filter is called if any audit_names[] have been
676  * collected during syscall processing.  We only check rules in sublists at hash
677  * buckets applicable to the inode numbers in audit_names[].
678  * Regarding audit_state, same rules apply as for audit_filter_syscall().
679  */
680 enum audit_state audit_filter_inodes(struct task_struct *tsk,
681 				     struct audit_context *ctx)
682 {
683 	int i;
684 	struct audit_entry *e;
685 	enum audit_state state;
686 
687 	if (audit_pid && tsk->tgid == audit_pid)
688 		return AUDIT_DISABLED;
689 
690 	rcu_read_lock();
691 	for (i = 0; i < ctx->name_count; i++) {
692 		int word = AUDIT_WORD(ctx->major);
693 		int bit  = AUDIT_BIT(ctx->major);
694 		struct audit_names *n = &ctx->names[i];
695 		int h = audit_hash_ino((u32)n->ino);
696 		struct list_head *list = &audit_inode_hash[h];
697 
698 		if (list_empty(list))
699 			continue;
700 
701 		list_for_each_entry_rcu(e, list, list) {
702 			if ((e->rule.mask[word] & bit) == bit &&
703 			    audit_filter_rules(tsk, &e->rule, ctx, n, &state)) {
704 				rcu_read_unlock();
705 				return state;
706 			}
707 		}
708 	}
709 	rcu_read_unlock();
710 	return AUDIT_BUILD_CONTEXT;
711 }
712 
713 void audit_set_auditable(struct audit_context *ctx)
714 {
715 	ctx->auditable = 1;
716 }
717 
718 static inline struct audit_context *audit_get_context(struct task_struct *tsk,
719 						      int return_valid,
720 						      int return_code)
721 {
722 	struct audit_context *context = tsk->audit_context;
723 
724 	if (likely(!context))
725 		return NULL;
726 	context->return_valid = return_valid;
727 
728 	/*
729 	 * we need to fix up the return code in the audit logs if the actual
730 	 * return codes are later going to be fixed up by the arch specific
731 	 * signal handlers
732 	 *
733 	 * This is actually a test for:
734 	 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
735 	 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
736 	 *
737 	 * but is faster than a bunch of ||
738 	 */
739 	if (unlikely(return_code <= -ERESTARTSYS) &&
740 	    (return_code >= -ERESTART_RESTARTBLOCK) &&
741 	    (return_code != -ENOIOCTLCMD))
742 		context->return_code = -EINTR;
743 	else
744 		context->return_code  = return_code;
745 
746 	if (context->in_syscall && !context->dummy && !context->auditable) {
747 		enum audit_state state;
748 
749 		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
750 		if (state == AUDIT_RECORD_CONTEXT) {
751 			context->auditable = 1;
752 			goto get_context;
753 		}
754 
755 		state = audit_filter_inodes(tsk, context);
756 		if (state == AUDIT_RECORD_CONTEXT)
757 			context->auditable = 1;
758 
759 	}
760 
761 get_context:
762 
763 	tsk->audit_context = NULL;
764 	return context;
765 }
766 
767 static inline void audit_free_names(struct audit_context *context)
768 {
769 	int i;
770 
771 #if AUDIT_DEBUG == 2
772 	if (context->auditable
773 	    ||context->put_count + context->ino_count != context->name_count) {
774 		printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
775 		       " name_count=%d put_count=%d"
776 		       " ino_count=%d [NOT freeing]\n",
777 		       __FILE__, __LINE__,
778 		       context->serial, context->major, context->in_syscall,
779 		       context->name_count, context->put_count,
780 		       context->ino_count);
781 		for (i = 0; i < context->name_count; i++) {
782 			printk(KERN_ERR "names[%d] = %p = %s\n", i,
783 			       context->names[i].name,
784 			       context->names[i].name ?: "(null)");
785 		}
786 		dump_stack();
787 		return;
788 	}
789 #endif
790 #if AUDIT_DEBUG
791 	context->put_count  = 0;
792 	context->ino_count  = 0;
793 #endif
794 
795 	for (i = 0; i < context->name_count; i++) {
796 		if (context->names[i].name && context->names[i].name_put)
797 			__putname(context->names[i].name);
798 	}
799 	context->name_count = 0;
800 	path_put(&context->pwd);
801 	context->pwd.dentry = NULL;
802 	context->pwd.mnt = NULL;
803 }
804 
805 static inline void audit_free_aux(struct audit_context *context)
806 {
807 	struct audit_aux_data *aux;
808 
809 	while ((aux = context->aux)) {
810 		context->aux = aux->next;
811 		kfree(aux);
812 	}
813 	while ((aux = context->aux_pids)) {
814 		context->aux_pids = aux->next;
815 		kfree(aux);
816 	}
817 }
818 
819 static inline void audit_zero_context(struct audit_context *context,
820 				      enum audit_state state)
821 {
822 	memset(context, 0, sizeof(*context));
823 	context->state      = state;
824 }
825 
826 static inline struct audit_context *audit_alloc_context(enum audit_state state)
827 {
828 	struct audit_context *context;
829 
830 	if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
831 		return NULL;
832 	audit_zero_context(context, state);
833 	return context;
834 }
835 
836 /**
837  * audit_alloc - allocate an audit context block for a task
838  * @tsk: task
839  *
840  * Filter on the task information and allocate a per-task audit context
841  * if necessary.  Doing so turns on system call auditing for the
842  * specified task.  This is called from copy_process, so no lock is
843  * needed.
844  */
845 int audit_alloc(struct task_struct *tsk)
846 {
847 	struct audit_context *context;
848 	enum audit_state     state;
849 
850 	if (likely(!audit_ever_enabled))
851 		return 0; /* Return if not auditing. */
852 
853 	state = audit_filter_task(tsk);
854 	if (likely(state == AUDIT_DISABLED))
855 		return 0;
856 
857 	if (!(context = audit_alloc_context(state))) {
858 		audit_log_lost("out of memory in audit_alloc");
859 		return -ENOMEM;
860 	}
861 
862 	tsk->audit_context  = context;
863 	set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
864 	return 0;
865 }
866 
867 static inline void audit_free_context(struct audit_context *context)
868 {
869 	struct audit_context *previous;
870 	int		     count = 0;
871 
872 	do {
873 		previous = context->previous;
874 		if (previous || (count &&  count < 10)) {
875 			++count;
876 			printk(KERN_ERR "audit(:%d): major=%d name_count=%d:"
877 			       " freeing multiple contexts (%d)\n",
878 			       context->serial, context->major,
879 			       context->name_count, count);
880 		}
881 		audit_free_names(context);
882 		unroll_tree_refs(context, NULL, 0);
883 		free_tree_refs(context);
884 		audit_free_aux(context);
885 		kfree(context->filterkey);
886 		kfree(context);
887 		context  = previous;
888 	} while (context);
889 	if (count >= 10)
890 		printk(KERN_ERR "audit: freed %d contexts\n", count);
891 }
892 
893 void audit_log_task_context(struct audit_buffer *ab)
894 {
895 	char *ctx = NULL;
896 	unsigned len;
897 	int error;
898 	u32 sid;
899 
900 	security_task_getsecid(current, &sid);
901 	if (!sid)
902 		return;
903 
904 	error = security_secid_to_secctx(sid, &ctx, &len);
905 	if (error) {
906 		if (error != -EINVAL)
907 			goto error_path;
908 		return;
909 	}
910 
911 	audit_log_format(ab, " subj=%s", ctx);
912 	security_release_secctx(ctx, len);
913 	return;
914 
915 error_path:
916 	audit_panic("error in audit_log_task_context");
917 	return;
918 }
919 
920 EXPORT_SYMBOL(audit_log_task_context);
921 
922 static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
923 {
924 	char name[sizeof(tsk->comm)];
925 	struct mm_struct *mm = tsk->mm;
926 	struct vm_area_struct *vma;
927 
928 	/* tsk == current */
929 
930 	get_task_comm(name, tsk);
931 	audit_log_format(ab, " comm=");
932 	audit_log_untrustedstring(ab, name);
933 
934 	if (mm) {
935 		down_read(&mm->mmap_sem);
936 		vma = mm->mmap;
937 		while (vma) {
938 			if ((vma->vm_flags & VM_EXECUTABLE) &&
939 			    vma->vm_file) {
940 				audit_log_d_path(ab, "exe=",
941 						 &vma->vm_file->f_path);
942 				break;
943 			}
944 			vma = vma->vm_next;
945 		}
946 		up_read(&mm->mmap_sem);
947 	}
948 	audit_log_task_context(ab);
949 }
950 
951 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
952 				 uid_t auid, uid_t uid, unsigned int sessionid,
953 				 u32 sid, char *comm)
954 {
955 	struct audit_buffer *ab;
956 	char *ctx = NULL;
957 	u32 len;
958 	int rc = 0;
959 
960 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
961 	if (!ab)
962 		return rc;
963 
964 	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid,
965 			 uid, sessionid);
966 	if (security_secid_to_secctx(sid, &ctx, &len)) {
967 		audit_log_format(ab, " obj=(none)");
968 		rc = 1;
969 	} else {
970 		audit_log_format(ab, " obj=%s", ctx);
971 		security_release_secctx(ctx, len);
972 	}
973 	audit_log_format(ab, " ocomm=");
974 	audit_log_untrustedstring(ab, comm);
975 	audit_log_end(ab);
976 
977 	return rc;
978 }
979 
980 /*
981  * to_send and len_sent accounting are very loose estimates.  We aren't
982  * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being
983  * within about 500 bytes (next page boundry)
984  *
985  * why snprintf?  an int is up to 12 digits long.  if we just assumed when
986  * logging that a[%d]= was going to be 16 characters long we would be wasting
987  * space in every audit message.  In one 7500 byte message we can log up to
988  * about 1000 min size arguments.  That comes down to about 50% waste of space
989  * if we didn't do the snprintf to find out how long arg_num_len was.
990  */
991 static int audit_log_single_execve_arg(struct audit_context *context,
992 					struct audit_buffer **ab,
993 					int arg_num,
994 					size_t *len_sent,
995 					const char __user *p,
996 					char *buf)
997 {
998 	char arg_num_len_buf[12];
999 	const char __user *tmp_p = p;
1000 	/* how many digits are in arg_num? 3 is the length of a=\n */
1001 	size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 3;
1002 	size_t len, len_left, to_send;
1003 	size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN;
1004 	unsigned int i, has_cntl = 0, too_long = 0;
1005 	int ret;
1006 
1007 	/* strnlen_user includes the null we don't want to send */
1008 	len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1009 
1010 	/*
1011 	 * We just created this mm, if we can't find the strings
1012 	 * we just copied into it something is _very_ wrong. Similar
1013 	 * for strings that are too long, we should not have created
1014 	 * any.
1015 	 */
1016 	if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
1017 		WARN_ON(1);
1018 		send_sig(SIGKILL, current, 0);
1019 		return -1;
1020 	}
1021 
1022 	/* walk the whole argument looking for non-ascii chars */
1023 	do {
1024 		if (len_left > MAX_EXECVE_AUDIT_LEN)
1025 			to_send = MAX_EXECVE_AUDIT_LEN;
1026 		else
1027 			to_send = len_left;
1028 		ret = copy_from_user(buf, tmp_p, to_send);
1029 		/*
1030 		 * There is no reason for this copy to be short. We just
1031 		 * copied them here, and the mm hasn't been exposed to user-
1032 		 * space yet.
1033 		 */
1034 		if (ret) {
1035 			WARN_ON(1);
1036 			send_sig(SIGKILL, current, 0);
1037 			return -1;
1038 		}
1039 		buf[to_send] = '\0';
1040 		has_cntl = audit_string_contains_control(buf, to_send);
1041 		if (has_cntl) {
1042 			/*
1043 			 * hex messages get logged as 2 bytes, so we can only
1044 			 * send half as much in each message
1045 			 */
1046 			max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2;
1047 			break;
1048 		}
1049 		len_left -= to_send;
1050 		tmp_p += to_send;
1051 	} while (len_left > 0);
1052 
1053 	len_left = len;
1054 
1055 	if (len > max_execve_audit_len)
1056 		too_long = 1;
1057 
1058 	/* rewalk the argument actually logging the message */
1059 	for (i = 0; len_left > 0; i++) {
1060 		int room_left;
1061 
1062 		if (len_left > max_execve_audit_len)
1063 			to_send = max_execve_audit_len;
1064 		else
1065 			to_send = len_left;
1066 
1067 		/* do we have space left to send this argument in this ab? */
1068 		room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent;
1069 		if (has_cntl)
1070 			room_left -= (to_send * 2);
1071 		else
1072 			room_left -= to_send;
1073 		if (room_left < 0) {
1074 			*len_sent = 0;
1075 			audit_log_end(*ab);
1076 			*ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE);
1077 			if (!*ab)
1078 				return 0;
1079 		}
1080 
1081 		/*
1082 		 * first record needs to say how long the original string was
1083 		 * so we can be sure nothing was lost.
1084 		 */
1085 		if ((i == 0) && (too_long))
1086 			audit_log_format(*ab, "a%d_len=%zu ", arg_num,
1087 					 has_cntl ? 2*len : len);
1088 
1089 		/*
1090 		 * normally arguments are small enough to fit and we already
1091 		 * filled buf above when we checked for control characters
1092 		 * so don't bother with another copy_from_user
1093 		 */
1094 		if (len >= max_execve_audit_len)
1095 			ret = copy_from_user(buf, p, to_send);
1096 		else
1097 			ret = 0;
1098 		if (ret) {
1099 			WARN_ON(1);
1100 			send_sig(SIGKILL, current, 0);
1101 			return -1;
1102 		}
1103 		buf[to_send] = '\0';
1104 
1105 		/* actually log it */
1106 		audit_log_format(*ab, "a%d", arg_num);
1107 		if (too_long)
1108 			audit_log_format(*ab, "[%d]", i);
1109 		audit_log_format(*ab, "=");
1110 		if (has_cntl)
1111 			audit_log_n_hex(*ab, buf, to_send);
1112 		else
1113 			audit_log_format(*ab, "\"%s\"", buf);
1114 		audit_log_format(*ab, "\n");
1115 
1116 		p += to_send;
1117 		len_left -= to_send;
1118 		*len_sent += arg_num_len;
1119 		if (has_cntl)
1120 			*len_sent += to_send * 2;
1121 		else
1122 			*len_sent += to_send;
1123 	}
1124 	/* include the null we didn't log */
1125 	return len + 1;
1126 }
1127 
1128 static void audit_log_execve_info(struct audit_context *context,
1129 				  struct audit_buffer **ab,
1130 				  struct audit_aux_data_execve *axi)
1131 {
1132 	int i;
1133 	size_t len, len_sent = 0;
1134 	const char __user *p;
1135 	char *buf;
1136 
1137 	if (axi->mm != current->mm)
1138 		return; /* execve failed, no additional info */
1139 
1140 	p = (const char __user *)axi->mm->arg_start;
1141 
1142 	audit_log_format(*ab, "argc=%d ", axi->argc);
1143 
1144 	/*
1145 	 * we need some kernel buffer to hold the userspace args.  Just
1146 	 * allocate one big one rather than allocating one of the right size
1147 	 * for every single argument inside audit_log_single_execve_arg()
1148 	 * should be <8k allocation so should be pretty safe.
1149 	 */
1150 	buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1151 	if (!buf) {
1152 		audit_panic("out of memory for argv string\n");
1153 		return;
1154 	}
1155 
1156 	for (i = 0; i < axi->argc; i++) {
1157 		len = audit_log_single_execve_arg(context, ab, i,
1158 						  &len_sent, p, buf);
1159 		if (len <= 0)
1160 			break;
1161 		p += len;
1162 	}
1163 	kfree(buf);
1164 }
1165 
1166 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
1167 {
1168 	int i, call_panic = 0;
1169 	struct audit_buffer *ab;
1170 	struct audit_aux_data *aux;
1171 	const char *tty;
1172 
1173 	/* tsk == current */
1174 	context->pid = tsk->pid;
1175 	if (!context->ppid)
1176 		context->ppid = sys_getppid();
1177 	context->uid = tsk->uid;
1178 	context->gid = tsk->gid;
1179 	context->euid = tsk->euid;
1180 	context->suid = tsk->suid;
1181 	context->fsuid = tsk->fsuid;
1182 	context->egid = tsk->egid;
1183 	context->sgid = tsk->sgid;
1184 	context->fsgid = tsk->fsgid;
1185 	context->personality = tsk->personality;
1186 
1187 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1188 	if (!ab)
1189 		return;		/* audit_panic has been called */
1190 	audit_log_format(ab, "arch=%x syscall=%d",
1191 			 context->arch, context->major);
1192 	if (context->personality != PER_LINUX)
1193 		audit_log_format(ab, " per=%lx", context->personality);
1194 	if (context->return_valid)
1195 		audit_log_format(ab, " success=%s exit=%ld",
1196 				 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
1197 				 context->return_code);
1198 
1199 	mutex_lock(&tty_mutex);
1200 	read_lock(&tasklist_lock);
1201 	if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
1202 		tty = tsk->signal->tty->name;
1203 	else
1204 		tty = "(none)";
1205 	read_unlock(&tasklist_lock);
1206 	audit_log_format(ab,
1207 		  " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
1208 		  " ppid=%d pid=%d auid=%u uid=%u gid=%u"
1209 		  " euid=%u suid=%u fsuid=%u"
1210 		  " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
1211 		  context->argv[0],
1212 		  context->argv[1],
1213 		  context->argv[2],
1214 		  context->argv[3],
1215 		  context->name_count,
1216 		  context->ppid,
1217 		  context->pid,
1218 		  tsk->loginuid,
1219 		  context->uid,
1220 		  context->gid,
1221 		  context->euid, context->suid, context->fsuid,
1222 		  context->egid, context->sgid, context->fsgid, tty,
1223 		  tsk->sessionid);
1224 
1225 	mutex_unlock(&tty_mutex);
1226 
1227 	audit_log_task_info(ab, tsk);
1228 	if (context->filterkey) {
1229 		audit_log_format(ab, " key=");
1230 		audit_log_untrustedstring(ab, context->filterkey);
1231 	} else
1232 		audit_log_format(ab, " key=(null)");
1233 	audit_log_end(ab);
1234 
1235 	for (aux = context->aux; aux; aux = aux->next) {
1236 
1237 		ab = audit_log_start(context, GFP_KERNEL, aux->type);
1238 		if (!ab)
1239 			continue; /* audit_panic has been called */
1240 
1241 		switch (aux->type) {
1242 		case AUDIT_MQ_OPEN: {
1243 			struct audit_aux_data_mq_open *axi = (void *)aux;
1244 			audit_log_format(ab,
1245 				"oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld "
1246 				"mq_msgsize=%ld mq_curmsgs=%ld",
1247 				axi->oflag, axi->mode, axi->attr.mq_flags,
1248 				axi->attr.mq_maxmsg, axi->attr.mq_msgsize,
1249 				axi->attr.mq_curmsgs);
1250 			break; }
1251 
1252 		case AUDIT_MQ_SENDRECV: {
1253 			struct audit_aux_data_mq_sendrecv *axi = (void *)aux;
1254 			audit_log_format(ab,
1255 				"mqdes=%d msg_len=%zd msg_prio=%u "
1256 				"abs_timeout_sec=%ld abs_timeout_nsec=%ld",
1257 				axi->mqdes, axi->msg_len, axi->msg_prio,
1258 				axi->abs_timeout.tv_sec, axi->abs_timeout.tv_nsec);
1259 			break; }
1260 
1261 		case AUDIT_MQ_NOTIFY: {
1262 			struct audit_aux_data_mq_notify *axi = (void *)aux;
1263 			audit_log_format(ab,
1264 				"mqdes=%d sigev_signo=%d",
1265 				axi->mqdes,
1266 				axi->notification.sigev_signo);
1267 			break; }
1268 
1269 		case AUDIT_MQ_GETSETATTR: {
1270 			struct audit_aux_data_mq_getsetattr *axi = (void *)aux;
1271 			audit_log_format(ab,
1272 				"mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1273 				"mq_curmsgs=%ld ",
1274 				axi->mqdes,
1275 				axi->mqstat.mq_flags, axi->mqstat.mq_maxmsg,
1276 				axi->mqstat.mq_msgsize, axi->mqstat.mq_curmsgs);
1277 			break; }
1278 
1279 		case AUDIT_IPC: {
1280 			struct audit_aux_data_ipcctl *axi = (void *)aux;
1281 			audit_log_format(ab,
1282 				 "ouid=%u ogid=%u mode=%#o",
1283 				 axi->uid, axi->gid, axi->mode);
1284 			if (axi->osid != 0) {
1285 				char *ctx = NULL;
1286 				u32 len;
1287 				if (security_secid_to_secctx(
1288 						axi->osid, &ctx, &len)) {
1289 					audit_log_format(ab, " osid=%u",
1290 							axi->osid);
1291 					call_panic = 1;
1292 				} else {
1293 					audit_log_format(ab, " obj=%s", ctx);
1294 					security_release_secctx(ctx, len);
1295 				}
1296 			}
1297 			break; }
1298 
1299 		case AUDIT_IPC_SET_PERM: {
1300 			struct audit_aux_data_ipcctl *axi = (void *)aux;
1301 			audit_log_format(ab,
1302 				"qbytes=%lx ouid=%u ogid=%u mode=%#o",
1303 				axi->qbytes, axi->uid, axi->gid, axi->mode);
1304 			break; }
1305 
1306 		case AUDIT_EXECVE: {
1307 			struct audit_aux_data_execve *axi = (void *)aux;
1308 			audit_log_execve_info(context, &ab, axi);
1309 			break; }
1310 
1311 		case AUDIT_SOCKETCALL: {
1312 			struct audit_aux_data_socketcall *axs = (void *)aux;
1313 			audit_log_format(ab, "nargs=%d", axs->nargs);
1314 			for (i=0; i<axs->nargs; i++)
1315 				audit_log_format(ab, " a%d=%lx", i, axs->args[i]);
1316 			break; }
1317 
1318 		case AUDIT_SOCKADDR: {
1319 			struct audit_aux_data_sockaddr *axs = (void *)aux;
1320 
1321 			audit_log_format(ab, "saddr=");
1322 			audit_log_n_hex(ab, axs->a, axs->len);
1323 			break; }
1324 
1325 		case AUDIT_FD_PAIR: {
1326 			struct audit_aux_data_fd_pair *axs = (void *)aux;
1327 			audit_log_format(ab, "fd0=%d fd1=%d", axs->fd[0], axs->fd[1]);
1328 			break; }
1329 
1330 		}
1331 		audit_log_end(ab);
1332 	}
1333 
1334 	for (aux = context->aux_pids; aux; aux = aux->next) {
1335 		struct audit_aux_data_pids *axs = (void *)aux;
1336 
1337 		for (i = 0; i < axs->pid_count; i++)
1338 			if (audit_log_pid_context(context, axs->target_pid[i],
1339 						  axs->target_auid[i],
1340 						  axs->target_uid[i],
1341 						  axs->target_sessionid[i],
1342 						  axs->target_sid[i],
1343 						  axs->target_comm[i]))
1344 				call_panic = 1;
1345 	}
1346 
1347 	if (context->target_pid &&
1348 	    audit_log_pid_context(context, context->target_pid,
1349 				  context->target_auid, context->target_uid,
1350 				  context->target_sessionid,
1351 				  context->target_sid, context->target_comm))
1352 			call_panic = 1;
1353 
1354 	if (context->pwd.dentry && context->pwd.mnt) {
1355 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1356 		if (ab) {
1357 			audit_log_d_path(ab, "cwd=", &context->pwd);
1358 			audit_log_end(ab);
1359 		}
1360 	}
1361 	for (i = 0; i < context->name_count; i++) {
1362 		struct audit_names *n = &context->names[i];
1363 
1364 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1365 		if (!ab)
1366 			continue; /* audit_panic has been called */
1367 
1368 		audit_log_format(ab, "item=%d", i);
1369 
1370 		if (n->name) {
1371 			switch(n->name_len) {
1372 			case AUDIT_NAME_FULL:
1373 				/* log the full path */
1374 				audit_log_format(ab, " name=");
1375 				audit_log_untrustedstring(ab, n->name);
1376 				break;
1377 			case 0:
1378 				/* name was specified as a relative path and the
1379 				 * directory component is the cwd */
1380 				audit_log_d_path(ab, " name=", &context->pwd);
1381 				break;
1382 			default:
1383 				/* log the name's directory component */
1384 				audit_log_format(ab, " name=");
1385 				audit_log_n_untrustedstring(ab, n->name,
1386 							    n->name_len);
1387 			}
1388 		} else
1389 			audit_log_format(ab, " name=(null)");
1390 
1391 		if (n->ino != (unsigned long)-1) {
1392 			audit_log_format(ab, " inode=%lu"
1393 					 " dev=%02x:%02x mode=%#o"
1394 					 " ouid=%u ogid=%u rdev=%02x:%02x",
1395 					 n->ino,
1396 					 MAJOR(n->dev),
1397 					 MINOR(n->dev),
1398 					 n->mode,
1399 					 n->uid,
1400 					 n->gid,
1401 					 MAJOR(n->rdev),
1402 					 MINOR(n->rdev));
1403 		}
1404 		if (n->osid != 0) {
1405 			char *ctx = NULL;
1406 			u32 len;
1407 			if (security_secid_to_secctx(
1408 				n->osid, &ctx, &len)) {
1409 				audit_log_format(ab, " osid=%u", n->osid);
1410 				call_panic = 2;
1411 			} else {
1412 				audit_log_format(ab, " obj=%s", ctx);
1413 				security_release_secctx(ctx, len);
1414 			}
1415 		}
1416 
1417 		audit_log_end(ab);
1418 	}
1419 
1420 	/* Send end of event record to help user space know we are finished */
1421 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1422 	if (ab)
1423 		audit_log_end(ab);
1424 	if (call_panic)
1425 		audit_panic("error converting sid to string");
1426 }
1427 
1428 /**
1429  * audit_free - free a per-task audit context
1430  * @tsk: task whose audit context block to free
1431  *
1432  * Called from copy_process and do_exit
1433  */
1434 void audit_free(struct task_struct *tsk)
1435 {
1436 	struct audit_context *context;
1437 
1438 	context = audit_get_context(tsk, 0, 0);
1439 	if (likely(!context))
1440 		return;
1441 
1442 	/* Check for system calls that do not go through the exit
1443 	 * function (e.g., exit_group), then free context block.
1444 	 * We use GFP_ATOMIC here because we might be doing this
1445 	 * in the context of the idle thread */
1446 	/* that can happen only if we are called from do_exit() */
1447 	if (context->in_syscall && context->auditable)
1448 		audit_log_exit(context, tsk);
1449 
1450 	audit_free_context(context);
1451 }
1452 
1453 /**
1454  * audit_syscall_entry - fill in an audit record at syscall entry
1455  * @tsk: task being audited
1456  * @arch: architecture type
1457  * @major: major syscall type (function)
1458  * @a1: additional syscall register 1
1459  * @a2: additional syscall register 2
1460  * @a3: additional syscall register 3
1461  * @a4: additional syscall register 4
1462  *
1463  * Fill in audit context at syscall entry.  This only happens if the
1464  * audit context was created when the task was created and the state or
1465  * filters demand the audit context be built.  If the state from the
1466  * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1467  * then the record will be written at syscall exit time (otherwise, it
1468  * will only be written if another part of the kernel requests that it
1469  * be written).
1470  */
1471 void audit_syscall_entry(int arch, int major,
1472 			 unsigned long a1, unsigned long a2,
1473 			 unsigned long a3, unsigned long a4)
1474 {
1475 	struct task_struct *tsk = current;
1476 	struct audit_context *context = tsk->audit_context;
1477 	enum audit_state     state;
1478 
1479 	BUG_ON(!context);
1480 
1481 	/*
1482 	 * This happens only on certain architectures that make system
1483 	 * calls in kernel_thread via the entry.S interface, instead of
1484 	 * with direct calls.  (If you are porting to a new
1485 	 * architecture, hitting this condition can indicate that you
1486 	 * got the _exit/_leave calls backward in entry.S.)
1487 	 *
1488 	 * i386     no
1489 	 * x86_64   no
1490 	 * ppc64    yes (see arch/powerpc/platforms/iseries/misc.S)
1491 	 *
1492 	 * This also happens with vm86 emulation in a non-nested manner
1493 	 * (entries without exits), so this case must be caught.
1494 	 */
1495 	if (context->in_syscall) {
1496 		struct audit_context *newctx;
1497 
1498 #if AUDIT_DEBUG
1499 		printk(KERN_ERR
1500 		       "audit(:%d) pid=%d in syscall=%d;"
1501 		       " entering syscall=%d\n",
1502 		       context->serial, tsk->pid, context->major, major);
1503 #endif
1504 		newctx = audit_alloc_context(context->state);
1505 		if (newctx) {
1506 			newctx->previous   = context;
1507 			context		   = newctx;
1508 			tsk->audit_context = newctx;
1509 		} else	{
1510 			/* If we can't alloc a new context, the best we
1511 			 * can do is to leak memory (any pending putname
1512 			 * will be lost).  The only other alternative is
1513 			 * to abandon auditing. */
1514 			audit_zero_context(context, context->state);
1515 		}
1516 	}
1517 	BUG_ON(context->in_syscall || context->name_count);
1518 
1519 	if (!audit_enabled)
1520 		return;
1521 
1522 	context->arch	    = arch;
1523 	context->major      = major;
1524 	context->argv[0]    = a1;
1525 	context->argv[1]    = a2;
1526 	context->argv[2]    = a3;
1527 	context->argv[3]    = a4;
1528 
1529 	state = context->state;
1530 	context->dummy = !audit_n_rules;
1531 	if (!context->dummy && (state == AUDIT_SETUP_CONTEXT || state == AUDIT_BUILD_CONTEXT))
1532 		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1533 	if (likely(state == AUDIT_DISABLED))
1534 		return;
1535 
1536 	context->serial     = 0;
1537 	context->ctime      = CURRENT_TIME;
1538 	context->in_syscall = 1;
1539 	context->auditable  = !!(state == AUDIT_RECORD_CONTEXT);
1540 	context->ppid       = 0;
1541 }
1542 
1543 /**
1544  * audit_syscall_exit - deallocate audit context after a system call
1545  * @tsk: task being audited
1546  * @valid: success/failure flag
1547  * @return_code: syscall return value
1548  *
1549  * Tear down after system call.  If the audit context has been marked as
1550  * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1551  * filtering, or because some other part of the kernel write an audit
1552  * message), then write out the syscall information.  In call cases,
1553  * free the names stored from getname().
1554  */
1555 void audit_syscall_exit(int valid, long return_code)
1556 {
1557 	struct task_struct *tsk = current;
1558 	struct audit_context *context;
1559 
1560 	context = audit_get_context(tsk, valid, return_code);
1561 
1562 	if (likely(!context))
1563 		return;
1564 
1565 	if (context->in_syscall && context->auditable)
1566 		audit_log_exit(context, tsk);
1567 
1568 	context->in_syscall = 0;
1569 	context->auditable  = 0;
1570 
1571 	if (context->previous) {
1572 		struct audit_context *new_context = context->previous;
1573 		context->previous  = NULL;
1574 		audit_free_context(context);
1575 		tsk->audit_context = new_context;
1576 	} else {
1577 		audit_free_names(context);
1578 		unroll_tree_refs(context, NULL, 0);
1579 		audit_free_aux(context);
1580 		context->aux = NULL;
1581 		context->aux_pids = NULL;
1582 		context->target_pid = 0;
1583 		context->target_sid = 0;
1584 		kfree(context->filterkey);
1585 		context->filterkey = NULL;
1586 		tsk->audit_context = context;
1587 	}
1588 }
1589 
1590 static inline void handle_one(const struct inode *inode)
1591 {
1592 #ifdef CONFIG_AUDIT_TREE
1593 	struct audit_context *context;
1594 	struct audit_tree_refs *p;
1595 	struct audit_chunk *chunk;
1596 	int count;
1597 	if (likely(list_empty(&inode->inotify_watches)))
1598 		return;
1599 	context = current->audit_context;
1600 	p = context->trees;
1601 	count = context->tree_count;
1602 	rcu_read_lock();
1603 	chunk = audit_tree_lookup(inode);
1604 	rcu_read_unlock();
1605 	if (!chunk)
1606 		return;
1607 	if (likely(put_tree_ref(context, chunk)))
1608 		return;
1609 	if (unlikely(!grow_tree_refs(context))) {
1610 		printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
1611 		audit_set_auditable(context);
1612 		audit_put_chunk(chunk);
1613 		unroll_tree_refs(context, p, count);
1614 		return;
1615 	}
1616 	put_tree_ref(context, chunk);
1617 #endif
1618 }
1619 
1620 static void handle_path(const struct dentry *dentry)
1621 {
1622 #ifdef CONFIG_AUDIT_TREE
1623 	struct audit_context *context;
1624 	struct audit_tree_refs *p;
1625 	const struct dentry *d, *parent;
1626 	struct audit_chunk *drop;
1627 	unsigned long seq;
1628 	int count;
1629 
1630 	context = current->audit_context;
1631 	p = context->trees;
1632 	count = context->tree_count;
1633 retry:
1634 	drop = NULL;
1635 	d = dentry;
1636 	rcu_read_lock();
1637 	seq = read_seqbegin(&rename_lock);
1638 	for(;;) {
1639 		struct inode *inode = d->d_inode;
1640 		if (inode && unlikely(!list_empty(&inode->inotify_watches))) {
1641 			struct audit_chunk *chunk;
1642 			chunk = audit_tree_lookup(inode);
1643 			if (chunk) {
1644 				if (unlikely(!put_tree_ref(context, chunk))) {
1645 					drop = chunk;
1646 					break;
1647 				}
1648 			}
1649 		}
1650 		parent = d->d_parent;
1651 		if (parent == d)
1652 			break;
1653 		d = parent;
1654 	}
1655 	if (unlikely(read_seqretry(&rename_lock, seq) || drop)) {  /* in this order */
1656 		rcu_read_unlock();
1657 		if (!drop) {
1658 			/* just a race with rename */
1659 			unroll_tree_refs(context, p, count);
1660 			goto retry;
1661 		}
1662 		audit_put_chunk(drop);
1663 		if (grow_tree_refs(context)) {
1664 			/* OK, got more space */
1665 			unroll_tree_refs(context, p, count);
1666 			goto retry;
1667 		}
1668 		/* too bad */
1669 		printk(KERN_WARNING
1670 			"out of memory, audit has lost a tree reference\n");
1671 		unroll_tree_refs(context, p, count);
1672 		audit_set_auditable(context);
1673 		return;
1674 	}
1675 	rcu_read_unlock();
1676 #endif
1677 }
1678 
1679 /**
1680  * audit_getname - add a name to the list
1681  * @name: name to add
1682  *
1683  * Add a name to the list of audit names for this context.
1684  * Called from fs/namei.c:getname().
1685  */
1686 void __audit_getname(const char *name)
1687 {
1688 	struct audit_context *context = current->audit_context;
1689 
1690 	if (IS_ERR(name) || !name)
1691 		return;
1692 
1693 	if (!context->in_syscall) {
1694 #if AUDIT_DEBUG == 2
1695 		printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
1696 		       __FILE__, __LINE__, context->serial, name);
1697 		dump_stack();
1698 #endif
1699 		return;
1700 	}
1701 	BUG_ON(context->name_count >= AUDIT_NAMES);
1702 	context->names[context->name_count].name = name;
1703 	context->names[context->name_count].name_len = AUDIT_NAME_FULL;
1704 	context->names[context->name_count].name_put = 1;
1705 	context->names[context->name_count].ino  = (unsigned long)-1;
1706 	context->names[context->name_count].osid = 0;
1707 	++context->name_count;
1708 	if (!context->pwd.dentry) {
1709 		read_lock(&current->fs->lock);
1710 		context->pwd = current->fs->pwd;
1711 		path_get(&current->fs->pwd);
1712 		read_unlock(&current->fs->lock);
1713 	}
1714 
1715 }
1716 
1717 /* audit_putname - intercept a putname request
1718  * @name: name to intercept and delay for putname
1719  *
1720  * If we have stored the name from getname in the audit context,
1721  * then we delay the putname until syscall exit.
1722  * Called from include/linux/fs.h:putname().
1723  */
1724 void audit_putname(const char *name)
1725 {
1726 	struct audit_context *context = current->audit_context;
1727 
1728 	BUG_ON(!context);
1729 	if (!context->in_syscall) {
1730 #if AUDIT_DEBUG == 2
1731 		printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n",
1732 		       __FILE__, __LINE__, context->serial, name);
1733 		if (context->name_count) {
1734 			int i;
1735 			for (i = 0; i < context->name_count; i++)
1736 				printk(KERN_ERR "name[%d] = %p = %s\n", i,
1737 				       context->names[i].name,
1738 				       context->names[i].name ?: "(null)");
1739 		}
1740 #endif
1741 		__putname(name);
1742 	}
1743 #if AUDIT_DEBUG
1744 	else {
1745 		++context->put_count;
1746 		if (context->put_count > context->name_count) {
1747 			printk(KERN_ERR "%s:%d(:%d): major=%d"
1748 			       " in_syscall=%d putname(%p) name_count=%d"
1749 			       " put_count=%d\n",
1750 			       __FILE__, __LINE__,
1751 			       context->serial, context->major,
1752 			       context->in_syscall, name, context->name_count,
1753 			       context->put_count);
1754 			dump_stack();
1755 		}
1756 	}
1757 #endif
1758 }
1759 
1760 static int audit_inc_name_count(struct audit_context *context,
1761 				const struct inode *inode)
1762 {
1763 	if (context->name_count >= AUDIT_NAMES) {
1764 		if (inode)
1765 			printk(KERN_DEBUG "name_count maxed, losing inode data: "
1766 			       "dev=%02x:%02x, inode=%lu\n",
1767 			       MAJOR(inode->i_sb->s_dev),
1768 			       MINOR(inode->i_sb->s_dev),
1769 			       inode->i_ino);
1770 
1771 		else
1772 			printk(KERN_DEBUG "name_count maxed, losing inode data\n");
1773 		return 1;
1774 	}
1775 	context->name_count++;
1776 #if AUDIT_DEBUG
1777 	context->ino_count++;
1778 #endif
1779 	return 0;
1780 }
1781 
1782 /* Copy inode data into an audit_names. */
1783 static void audit_copy_inode(struct audit_names *name, const struct inode *inode)
1784 {
1785 	name->ino   = inode->i_ino;
1786 	name->dev   = inode->i_sb->s_dev;
1787 	name->mode  = inode->i_mode;
1788 	name->uid   = inode->i_uid;
1789 	name->gid   = inode->i_gid;
1790 	name->rdev  = inode->i_rdev;
1791 	security_inode_getsecid(inode, &name->osid);
1792 }
1793 
1794 /**
1795  * audit_inode - store the inode and device from a lookup
1796  * @name: name being audited
1797  * @dentry: dentry being audited
1798  *
1799  * Called from fs/namei.c:path_lookup().
1800  */
1801 void __audit_inode(const char *name, const struct dentry *dentry)
1802 {
1803 	int idx;
1804 	struct audit_context *context = current->audit_context;
1805 	const struct inode *inode = dentry->d_inode;
1806 
1807 	if (!context->in_syscall)
1808 		return;
1809 	if (context->name_count
1810 	    && context->names[context->name_count-1].name
1811 	    && context->names[context->name_count-1].name == name)
1812 		idx = context->name_count - 1;
1813 	else if (context->name_count > 1
1814 		 && context->names[context->name_count-2].name
1815 		 && context->names[context->name_count-2].name == name)
1816 		idx = context->name_count - 2;
1817 	else {
1818 		/* FIXME: how much do we care about inodes that have no
1819 		 * associated name? */
1820 		if (audit_inc_name_count(context, inode))
1821 			return;
1822 		idx = context->name_count - 1;
1823 		context->names[idx].name = NULL;
1824 	}
1825 	handle_path(dentry);
1826 	audit_copy_inode(&context->names[idx], inode);
1827 }
1828 
1829 /**
1830  * audit_inode_child - collect inode info for created/removed objects
1831  * @dname: inode's dentry name
1832  * @dentry: dentry being audited
1833  * @parent: inode of dentry parent
1834  *
1835  * For syscalls that create or remove filesystem objects, audit_inode
1836  * can only collect information for the filesystem object's parent.
1837  * This call updates the audit context with the child's information.
1838  * Syscalls that create a new filesystem object must be hooked after
1839  * the object is created.  Syscalls that remove a filesystem object
1840  * must be hooked prior, in order to capture the target inode during
1841  * unsuccessful attempts.
1842  */
1843 void __audit_inode_child(const char *dname, const struct dentry *dentry,
1844 			 const struct inode *parent)
1845 {
1846 	int idx;
1847 	struct audit_context *context = current->audit_context;
1848 	const char *found_parent = NULL, *found_child = NULL;
1849 	const struct inode *inode = dentry->d_inode;
1850 	int dirlen = 0;
1851 
1852 	if (!context->in_syscall)
1853 		return;
1854 
1855 	if (inode)
1856 		handle_one(inode);
1857 	/* determine matching parent */
1858 	if (!dname)
1859 		goto add_names;
1860 
1861 	/* parent is more likely, look for it first */
1862 	for (idx = 0; idx < context->name_count; idx++) {
1863 		struct audit_names *n = &context->names[idx];
1864 
1865 		if (!n->name)
1866 			continue;
1867 
1868 		if (n->ino == parent->i_ino &&
1869 		    !audit_compare_dname_path(dname, n->name, &dirlen)) {
1870 			n->name_len = dirlen; /* update parent data in place */
1871 			found_parent = n->name;
1872 			goto add_names;
1873 		}
1874 	}
1875 
1876 	/* no matching parent, look for matching child */
1877 	for (idx = 0; idx < context->name_count; idx++) {
1878 		struct audit_names *n = &context->names[idx];
1879 
1880 		if (!n->name)
1881 			continue;
1882 
1883 		/* strcmp() is the more likely scenario */
1884 		if (!strcmp(dname, n->name) ||
1885 		     !audit_compare_dname_path(dname, n->name, &dirlen)) {
1886 			if (inode)
1887 				audit_copy_inode(n, inode);
1888 			else
1889 				n->ino = (unsigned long)-1;
1890 			found_child = n->name;
1891 			goto add_names;
1892 		}
1893 	}
1894 
1895 add_names:
1896 	if (!found_parent) {
1897 		if (audit_inc_name_count(context, parent))
1898 			return;
1899 		idx = context->name_count - 1;
1900 		context->names[idx].name = NULL;
1901 		audit_copy_inode(&context->names[idx], parent);
1902 	}
1903 
1904 	if (!found_child) {
1905 		if (audit_inc_name_count(context, inode))
1906 			return;
1907 		idx = context->name_count - 1;
1908 
1909 		/* Re-use the name belonging to the slot for a matching parent
1910 		 * directory. All names for this context are relinquished in
1911 		 * audit_free_names() */
1912 		if (found_parent) {
1913 			context->names[idx].name = found_parent;
1914 			context->names[idx].name_len = AUDIT_NAME_FULL;
1915 			/* don't call __putname() */
1916 			context->names[idx].name_put = 0;
1917 		} else {
1918 			context->names[idx].name = NULL;
1919 		}
1920 
1921 		if (inode)
1922 			audit_copy_inode(&context->names[idx], inode);
1923 		else
1924 			context->names[idx].ino = (unsigned long)-1;
1925 	}
1926 }
1927 EXPORT_SYMBOL_GPL(__audit_inode_child);
1928 
1929 /**
1930  * auditsc_get_stamp - get local copies of audit_context values
1931  * @ctx: audit_context for the task
1932  * @t: timespec to store time recorded in the audit_context
1933  * @serial: serial value that is recorded in the audit_context
1934  *
1935  * Also sets the context as auditable.
1936  */
1937 void auditsc_get_stamp(struct audit_context *ctx,
1938 		       struct timespec *t, unsigned int *serial)
1939 {
1940 	if (!ctx->serial)
1941 		ctx->serial = audit_serial();
1942 	t->tv_sec  = ctx->ctime.tv_sec;
1943 	t->tv_nsec = ctx->ctime.tv_nsec;
1944 	*serial    = ctx->serial;
1945 	ctx->auditable = 1;
1946 }
1947 
1948 /* global counter which is incremented every time something logs in */
1949 static atomic_t session_id = ATOMIC_INIT(0);
1950 
1951 /**
1952  * audit_set_loginuid - set a task's audit_context loginuid
1953  * @task: task whose audit context is being modified
1954  * @loginuid: loginuid value
1955  *
1956  * Returns 0.
1957  *
1958  * Called (set) from fs/proc/base.c::proc_loginuid_write().
1959  */
1960 int audit_set_loginuid(struct task_struct *task, uid_t loginuid)
1961 {
1962 	unsigned int sessionid = atomic_inc_return(&session_id);
1963 	struct audit_context *context = task->audit_context;
1964 
1965 	if (context && context->in_syscall) {
1966 		struct audit_buffer *ab;
1967 
1968 		ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
1969 		if (ab) {
1970 			audit_log_format(ab, "login pid=%d uid=%u "
1971 				"old auid=%u new auid=%u"
1972 				" old ses=%u new ses=%u",
1973 				task->pid, task->uid,
1974 				task->loginuid, loginuid,
1975 				task->sessionid, sessionid);
1976 			audit_log_end(ab);
1977 		}
1978 	}
1979 	task->sessionid = sessionid;
1980 	task->loginuid = loginuid;
1981 	return 0;
1982 }
1983 
1984 /**
1985  * __audit_mq_open - record audit data for a POSIX MQ open
1986  * @oflag: open flag
1987  * @mode: mode bits
1988  * @u_attr: queue attributes
1989  *
1990  * Returns 0 for success or NULL context or < 0 on error.
1991  */
1992 int __audit_mq_open(int oflag, mode_t mode, struct mq_attr __user *u_attr)
1993 {
1994 	struct audit_aux_data_mq_open *ax;
1995 	struct audit_context *context = current->audit_context;
1996 
1997 	if (!audit_enabled)
1998 		return 0;
1999 
2000 	if (likely(!context))
2001 		return 0;
2002 
2003 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2004 	if (!ax)
2005 		return -ENOMEM;
2006 
2007 	if (u_attr != NULL) {
2008 		if (copy_from_user(&ax->attr, u_attr, sizeof(ax->attr))) {
2009 			kfree(ax);
2010 			return -EFAULT;
2011 		}
2012 	} else
2013 		memset(&ax->attr, 0, sizeof(ax->attr));
2014 
2015 	ax->oflag = oflag;
2016 	ax->mode = mode;
2017 
2018 	ax->d.type = AUDIT_MQ_OPEN;
2019 	ax->d.next = context->aux;
2020 	context->aux = (void *)ax;
2021 	return 0;
2022 }
2023 
2024 /**
2025  * __audit_mq_timedsend - record audit data for a POSIX MQ timed send
2026  * @mqdes: MQ descriptor
2027  * @msg_len: Message length
2028  * @msg_prio: Message priority
2029  * @u_abs_timeout: Message timeout in absolute time
2030  *
2031  * Returns 0 for success or NULL context or < 0 on error.
2032  */
2033 int __audit_mq_timedsend(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2034 			const struct timespec __user *u_abs_timeout)
2035 {
2036 	struct audit_aux_data_mq_sendrecv *ax;
2037 	struct audit_context *context = current->audit_context;
2038 
2039 	if (!audit_enabled)
2040 		return 0;
2041 
2042 	if (likely(!context))
2043 		return 0;
2044 
2045 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2046 	if (!ax)
2047 		return -ENOMEM;
2048 
2049 	if (u_abs_timeout != NULL) {
2050 		if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) {
2051 			kfree(ax);
2052 			return -EFAULT;
2053 		}
2054 	} else
2055 		memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout));
2056 
2057 	ax->mqdes = mqdes;
2058 	ax->msg_len = msg_len;
2059 	ax->msg_prio = msg_prio;
2060 
2061 	ax->d.type = AUDIT_MQ_SENDRECV;
2062 	ax->d.next = context->aux;
2063 	context->aux = (void *)ax;
2064 	return 0;
2065 }
2066 
2067 /**
2068  * __audit_mq_timedreceive - record audit data for a POSIX MQ timed receive
2069  * @mqdes: MQ descriptor
2070  * @msg_len: Message length
2071  * @u_msg_prio: Message priority
2072  * @u_abs_timeout: Message timeout in absolute time
2073  *
2074  * Returns 0 for success or NULL context or < 0 on error.
2075  */
2076 int __audit_mq_timedreceive(mqd_t mqdes, size_t msg_len,
2077 				unsigned int __user *u_msg_prio,
2078 				const struct timespec __user *u_abs_timeout)
2079 {
2080 	struct audit_aux_data_mq_sendrecv *ax;
2081 	struct audit_context *context = current->audit_context;
2082 
2083 	if (!audit_enabled)
2084 		return 0;
2085 
2086 	if (likely(!context))
2087 		return 0;
2088 
2089 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2090 	if (!ax)
2091 		return -ENOMEM;
2092 
2093 	if (u_msg_prio != NULL) {
2094 		if (get_user(ax->msg_prio, u_msg_prio)) {
2095 			kfree(ax);
2096 			return -EFAULT;
2097 		}
2098 	} else
2099 		ax->msg_prio = 0;
2100 
2101 	if (u_abs_timeout != NULL) {
2102 		if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) {
2103 			kfree(ax);
2104 			return -EFAULT;
2105 		}
2106 	} else
2107 		memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout));
2108 
2109 	ax->mqdes = mqdes;
2110 	ax->msg_len = msg_len;
2111 
2112 	ax->d.type = AUDIT_MQ_SENDRECV;
2113 	ax->d.next = context->aux;
2114 	context->aux = (void *)ax;
2115 	return 0;
2116 }
2117 
2118 /**
2119  * __audit_mq_notify - record audit data for a POSIX MQ notify
2120  * @mqdes: MQ descriptor
2121  * @u_notification: Notification event
2122  *
2123  * Returns 0 for success or NULL context or < 0 on error.
2124  */
2125 
2126 int __audit_mq_notify(mqd_t mqdes, const struct sigevent __user *u_notification)
2127 {
2128 	struct audit_aux_data_mq_notify *ax;
2129 	struct audit_context *context = current->audit_context;
2130 
2131 	if (!audit_enabled)
2132 		return 0;
2133 
2134 	if (likely(!context))
2135 		return 0;
2136 
2137 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2138 	if (!ax)
2139 		return -ENOMEM;
2140 
2141 	if (u_notification != NULL) {
2142 		if (copy_from_user(&ax->notification, u_notification, sizeof(ax->notification))) {
2143 			kfree(ax);
2144 			return -EFAULT;
2145 		}
2146 	} else
2147 		memset(&ax->notification, 0, sizeof(ax->notification));
2148 
2149 	ax->mqdes = mqdes;
2150 
2151 	ax->d.type = AUDIT_MQ_NOTIFY;
2152 	ax->d.next = context->aux;
2153 	context->aux = (void *)ax;
2154 	return 0;
2155 }
2156 
2157 /**
2158  * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2159  * @mqdes: MQ descriptor
2160  * @mqstat: MQ flags
2161  *
2162  * Returns 0 for success or NULL context or < 0 on error.
2163  */
2164 int __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2165 {
2166 	struct audit_aux_data_mq_getsetattr *ax;
2167 	struct audit_context *context = current->audit_context;
2168 
2169 	if (!audit_enabled)
2170 		return 0;
2171 
2172 	if (likely(!context))
2173 		return 0;
2174 
2175 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2176 	if (!ax)
2177 		return -ENOMEM;
2178 
2179 	ax->mqdes = mqdes;
2180 	ax->mqstat = *mqstat;
2181 
2182 	ax->d.type = AUDIT_MQ_GETSETATTR;
2183 	ax->d.next = context->aux;
2184 	context->aux = (void *)ax;
2185 	return 0;
2186 }
2187 
2188 /**
2189  * audit_ipc_obj - record audit data for ipc object
2190  * @ipcp: ipc permissions
2191  *
2192  * Returns 0 for success or NULL context or < 0 on error.
2193  */
2194 int __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2195 {
2196 	struct audit_aux_data_ipcctl *ax;
2197 	struct audit_context *context = current->audit_context;
2198 
2199 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2200 	if (!ax)
2201 		return -ENOMEM;
2202 
2203 	ax->uid = ipcp->uid;
2204 	ax->gid = ipcp->gid;
2205 	ax->mode = ipcp->mode;
2206 	security_ipc_getsecid(ipcp, &ax->osid);
2207 	ax->d.type = AUDIT_IPC;
2208 	ax->d.next = context->aux;
2209 	context->aux = (void *)ax;
2210 	return 0;
2211 }
2212 
2213 /**
2214  * audit_ipc_set_perm - record audit data for new ipc permissions
2215  * @qbytes: msgq bytes
2216  * @uid: msgq user id
2217  * @gid: msgq group id
2218  * @mode: msgq mode (permissions)
2219  *
2220  * Returns 0 for success or NULL context or < 0 on error.
2221  */
2222 int __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode)
2223 {
2224 	struct audit_aux_data_ipcctl *ax;
2225 	struct audit_context *context = current->audit_context;
2226 
2227 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2228 	if (!ax)
2229 		return -ENOMEM;
2230 
2231 	ax->qbytes = qbytes;
2232 	ax->uid = uid;
2233 	ax->gid = gid;
2234 	ax->mode = mode;
2235 
2236 	ax->d.type = AUDIT_IPC_SET_PERM;
2237 	ax->d.next = context->aux;
2238 	context->aux = (void *)ax;
2239 	return 0;
2240 }
2241 
2242 int audit_bprm(struct linux_binprm *bprm)
2243 {
2244 	struct audit_aux_data_execve *ax;
2245 	struct audit_context *context = current->audit_context;
2246 
2247 	if (likely(!audit_enabled || !context || context->dummy))
2248 		return 0;
2249 
2250 	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2251 	if (!ax)
2252 		return -ENOMEM;
2253 
2254 	ax->argc = bprm->argc;
2255 	ax->envc = bprm->envc;
2256 	ax->mm = bprm->mm;
2257 	ax->d.type = AUDIT_EXECVE;
2258 	ax->d.next = context->aux;
2259 	context->aux = (void *)ax;
2260 	return 0;
2261 }
2262 
2263 
2264 /**
2265  * audit_socketcall - record audit data for sys_socketcall
2266  * @nargs: number of args
2267  * @args: args array
2268  *
2269  * Returns 0 for success or NULL context or < 0 on error.
2270  */
2271 int audit_socketcall(int nargs, unsigned long *args)
2272 {
2273 	struct audit_aux_data_socketcall *ax;
2274 	struct audit_context *context = current->audit_context;
2275 
2276 	if (likely(!context || context->dummy))
2277 		return 0;
2278 
2279 	ax = kmalloc(sizeof(*ax) + nargs * sizeof(unsigned long), GFP_KERNEL);
2280 	if (!ax)
2281 		return -ENOMEM;
2282 
2283 	ax->nargs = nargs;
2284 	memcpy(ax->args, args, nargs * sizeof(unsigned long));
2285 
2286 	ax->d.type = AUDIT_SOCKETCALL;
2287 	ax->d.next = context->aux;
2288 	context->aux = (void *)ax;
2289 	return 0;
2290 }
2291 
2292 /**
2293  * __audit_fd_pair - record audit data for pipe and socketpair
2294  * @fd1: the first file descriptor
2295  * @fd2: the second file descriptor
2296  *
2297  * Returns 0 for success or NULL context or < 0 on error.
2298  */
2299 int __audit_fd_pair(int fd1, int fd2)
2300 {
2301 	struct audit_context *context = current->audit_context;
2302 	struct audit_aux_data_fd_pair *ax;
2303 
2304 	if (likely(!context)) {
2305 		return 0;
2306 	}
2307 
2308 	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2309 	if (!ax) {
2310 		return -ENOMEM;
2311 	}
2312 
2313 	ax->fd[0] = fd1;
2314 	ax->fd[1] = fd2;
2315 
2316 	ax->d.type = AUDIT_FD_PAIR;
2317 	ax->d.next = context->aux;
2318 	context->aux = (void *)ax;
2319 	return 0;
2320 }
2321 
2322 /**
2323  * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2324  * @len: data length in user space
2325  * @a: data address in kernel space
2326  *
2327  * Returns 0 for success or NULL context or < 0 on error.
2328  */
2329 int audit_sockaddr(int len, void *a)
2330 {
2331 	struct audit_aux_data_sockaddr *ax;
2332 	struct audit_context *context = current->audit_context;
2333 
2334 	if (likely(!context || context->dummy))
2335 		return 0;
2336 
2337 	ax = kmalloc(sizeof(*ax) + len, GFP_KERNEL);
2338 	if (!ax)
2339 		return -ENOMEM;
2340 
2341 	ax->len = len;
2342 	memcpy(ax->a, a, len);
2343 
2344 	ax->d.type = AUDIT_SOCKADDR;
2345 	ax->d.next = context->aux;
2346 	context->aux = (void *)ax;
2347 	return 0;
2348 }
2349 
2350 void __audit_ptrace(struct task_struct *t)
2351 {
2352 	struct audit_context *context = current->audit_context;
2353 
2354 	context->target_pid = t->pid;
2355 	context->target_auid = audit_get_loginuid(t);
2356 	context->target_uid = t->uid;
2357 	context->target_sessionid = audit_get_sessionid(t);
2358 	security_task_getsecid(t, &context->target_sid);
2359 	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
2360 }
2361 
2362 /**
2363  * audit_signal_info - record signal info for shutting down audit subsystem
2364  * @sig: signal value
2365  * @t: task being signaled
2366  *
2367  * If the audit subsystem is being terminated, record the task (pid)
2368  * and uid that is doing that.
2369  */
2370 int __audit_signal_info(int sig, struct task_struct *t)
2371 {
2372 	struct audit_aux_data_pids *axp;
2373 	struct task_struct *tsk = current;
2374 	struct audit_context *ctx = tsk->audit_context;
2375 
2376 	if (audit_pid && t->tgid == audit_pid) {
2377 		if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1) {
2378 			audit_sig_pid = tsk->pid;
2379 			if (tsk->loginuid != -1)
2380 				audit_sig_uid = tsk->loginuid;
2381 			else
2382 				audit_sig_uid = tsk->uid;
2383 			security_task_getsecid(tsk, &audit_sig_sid);
2384 		}
2385 		if (!audit_signals || audit_dummy_context())
2386 			return 0;
2387 	}
2388 
2389 	/* optimize the common case by putting first signal recipient directly
2390 	 * in audit_context */
2391 	if (!ctx->target_pid) {
2392 		ctx->target_pid = t->tgid;
2393 		ctx->target_auid = audit_get_loginuid(t);
2394 		ctx->target_uid = t->uid;
2395 		ctx->target_sessionid = audit_get_sessionid(t);
2396 		security_task_getsecid(t, &ctx->target_sid);
2397 		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
2398 		return 0;
2399 	}
2400 
2401 	axp = (void *)ctx->aux_pids;
2402 	if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2403 		axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2404 		if (!axp)
2405 			return -ENOMEM;
2406 
2407 		axp->d.type = AUDIT_OBJ_PID;
2408 		axp->d.next = ctx->aux_pids;
2409 		ctx->aux_pids = (void *)axp;
2410 	}
2411 	BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2412 
2413 	axp->target_pid[axp->pid_count] = t->tgid;
2414 	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2415 	axp->target_uid[axp->pid_count] = t->uid;
2416 	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2417 	security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2418 	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
2419 	axp->pid_count++;
2420 
2421 	return 0;
2422 }
2423 
2424 /**
2425  * audit_core_dumps - record information about processes that end abnormally
2426  * @signr: signal value
2427  *
2428  * If a process ends with a core dump, something fishy is going on and we
2429  * should record the event for investigation.
2430  */
2431 void audit_core_dumps(long signr)
2432 {
2433 	struct audit_buffer *ab;
2434 	u32 sid;
2435 	uid_t auid = audit_get_loginuid(current);
2436 	unsigned int sessionid = audit_get_sessionid(current);
2437 
2438 	if (!audit_enabled)
2439 		return;
2440 
2441 	if (signr == SIGQUIT)	/* don't care for those */
2442 		return;
2443 
2444 	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2445 	audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2446 			auid, current->uid, current->gid, sessionid);
2447 	security_task_getsecid(current, &sid);
2448 	if (sid) {
2449 		char *ctx = NULL;
2450 		u32 len;
2451 
2452 		if (security_secid_to_secctx(sid, &ctx, &len))
2453 			audit_log_format(ab, " ssid=%u", sid);
2454 		else {
2455 			audit_log_format(ab, " subj=%s", ctx);
2456 			security_release_secctx(ctx, len);
2457 		}
2458 	}
2459 	audit_log_format(ab, " pid=%d comm=", current->pid);
2460 	audit_log_untrustedstring(ab, current->comm);
2461 	audit_log_format(ab, " sig=%ld", signr);
2462 	audit_log_end(ab);
2463 }
2464