xref: /openbmc/linux/kernel/auditsc.c (revision 367b8112)
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;
247 	if (unlikely(!ctx))
248 		return 0;
249 	n = ctx->major;
250 
251 	switch (audit_classify_syscall(ctx->arch, n)) {
252 	case 0:	/* native */
253 		if ((mask & AUDIT_PERM_WRITE) &&
254 		     audit_match_class(AUDIT_CLASS_WRITE, n))
255 			return 1;
256 		if ((mask & AUDIT_PERM_READ) &&
257 		     audit_match_class(AUDIT_CLASS_READ, n))
258 			return 1;
259 		if ((mask & AUDIT_PERM_ATTR) &&
260 		     audit_match_class(AUDIT_CLASS_CHATTR, n))
261 			return 1;
262 		return 0;
263 	case 1: /* 32bit on biarch */
264 		if ((mask & AUDIT_PERM_WRITE) &&
265 		     audit_match_class(AUDIT_CLASS_WRITE_32, n))
266 			return 1;
267 		if ((mask & AUDIT_PERM_READ) &&
268 		     audit_match_class(AUDIT_CLASS_READ_32, n))
269 			return 1;
270 		if ((mask & AUDIT_PERM_ATTR) &&
271 		     audit_match_class(AUDIT_CLASS_CHATTR_32, n))
272 			return 1;
273 		return 0;
274 	case 2: /* open */
275 		return mask & ACC_MODE(ctx->argv[1]);
276 	case 3: /* openat */
277 		return mask & ACC_MODE(ctx->argv[2]);
278 	case 4: /* socketcall */
279 		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
280 	case 5: /* execve */
281 		return mask & AUDIT_PERM_EXEC;
282 	default:
283 		return 0;
284 	}
285 }
286 
287 static int audit_match_filetype(struct audit_context *ctx, int which)
288 {
289 	unsigned index = which & ~S_IFMT;
290 	mode_t mode = which & S_IFMT;
291 
292 	if (unlikely(!ctx))
293 		return 0;
294 
295 	if (index >= ctx->name_count)
296 		return 0;
297 	if (ctx->names[index].ino == -1)
298 		return 0;
299 	if ((ctx->names[index].mode ^ mode) & S_IFMT)
300 		return 0;
301 	return 1;
302 }
303 
304 /*
305  * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
306  * ->first_trees points to its beginning, ->trees - to the current end of data.
307  * ->tree_count is the number of free entries in array pointed to by ->trees.
308  * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
309  * "empty" becomes (p, p, 31) afterwards.  We don't shrink the list (and seriously,
310  * it's going to remain 1-element for almost any setup) until we free context itself.
311  * References in it _are_ dropped - at the same time we free/drop aux stuff.
312  */
313 
314 #ifdef CONFIG_AUDIT_TREE
315 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
316 {
317 	struct audit_tree_refs *p = ctx->trees;
318 	int left = ctx->tree_count;
319 	if (likely(left)) {
320 		p->c[--left] = chunk;
321 		ctx->tree_count = left;
322 		return 1;
323 	}
324 	if (!p)
325 		return 0;
326 	p = p->next;
327 	if (p) {
328 		p->c[30] = chunk;
329 		ctx->trees = p;
330 		ctx->tree_count = 30;
331 		return 1;
332 	}
333 	return 0;
334 }
335 
336 static int grow_tree_refs(struct audit_context *ctx)
337 {
338 	struct audit_tree_refs *p = ctx->trees;
339 	ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
340 	if (!ctx->trees) {
341 		ctx->trees = p;
342 		return 0;
343 	}
344 	if (p)
345 		p->next = ctx->trees;
346 	else
347 		ctx->first_trees = ctx->trees;
348 	ctx->tree_count = 31;
349 	return 1;
350 }
351 #endif
352 
353 static void unroll_tree_refs(struct audit_context *ctx,
354 		      struct audit_tree_refs *p, int count)
355 {
356 #ifdef CONFIG_AUDIT_TREE
357 	struct audit_tree_refs *q;
358 	int n;
359 	if (!p) {
360 		/* we started with empty chain */
361 		p = ctx->first_trees;
362 		count = 31;
363 		/* if the very first allocation has failed, nothing to do */
364 		if (!p)
365 			return;
366 	}
367 	n = count;
368 	for (q = p; q != ctx->trees; q = q->next, n = 31) {
369 		while (n--) {
370 			audit_put_chunk(q->c[n]);
371 			q->c[n] = NULL;
372 		}
373 	}
374 	while (n-- > ctx->tree_count) {
375 		audit_put_chunk(q->c[n]);
376 		q->c[n] = NULL;
377 	}
378 	ctx->trees = p;
379 	ctx->tree_count = count;
380 #endif
381 }
382 
383 static void free_tree_refs(struct audit_context *ctx)
384 {
385 	struct audit_tree_refs *p, *q;
386 	for (p = ctx->first_trees; p; p = q) {
387 		q = p->next;
388 		kfree(p);
389 	}
390 }
391 
392 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
393 {
394 #ifdef CONFIG_AUDIT_TREE
395 	struct audit_tree_refs *p;
396 	int n;
397 	if (!tree)
398 		return 0;
399 	/* full ones */
400 	for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
401 		for (n = 0; n < 31; n++)
402 			if (audit_tree_match(p->c[n], tree))
403 				return 1;
404 	}
405 	/* partial */
406 	if (p) {
407 		for (n = ctx->tree_count; n < 31; n++)
408 			if (audit_tree_match(p->c[n], tree))
409 				return 1;
410 	}
411 #endif
412 	return 0;
413 }
414 
415 /* Determine if any context name data matches a rule's watch data */
416 /* Compare a task_struct with an audit_rule.  Return 1 on match, 0
417  * otherwise. */
418 static int audit_filter_rules(struct task_struct *tsk,
419 			      struct audit_krule *rule,
420 			      struct audit_context *ctx,
421 			      struct audit_names *name,
422 			      enum audit_state *state)
423 {
424 	int i, j, need_sid = 1;
425 	u32 sid;
426 
427 	for (i = 0; i < rule->field_count; i++) {
428 		struct audit_field *f = &rule->fields[i];
429 		int result = 0;
430 
431 		switch (f->type) {
432 		case AUDIT_PID:
433 			result = audit_comparator(tsk->pid, f->op, f->val);
434 			break;
435 		case AUDIT_PPID:
436 			if (ctx) {
437 				if (!ctx->ppid)
438 					ctx->ppid = sys_getppid();
439 				result = audit_comparator(ctx->ppid, f->op, f->val);
440 			}
441 			break;
442 		case AUDIT_UID:
443 			result = audit_comparator(tsk->uid, f->op, f->val);
444 			break;
445 		case AUDIT_EUID:
446 			result = audit_comparator(tsk->euid, f->op, f->val);
447 			break;
448 		case AUDIT_SUID:
449 			result = audit_comparator(tsk->suid, f->op, f->val);
450 			break;
451 		case AUDIT_FSUID:
452 			result = audit_comparator(tsk->fsuid, f->op, f->val);
453 			break;
454 		case AUDIT_GID:
455 			result = audit_comparator(tsk->gid, f->op, f->val);
456 			break;
457 		case AUDIT_EGID:
458 			result = audit_comparator(tsk->egid, f->op, f->val);
459 			break;
460 		case AUDIT_SGID:
461 			result = audit_comparator(tsk->sgid, f->op, f->val);
462 			break;
463 		case AUDIT_FSGID:
464 			result = audit_comparator(tsk->fsgid, f->op, f->val);
465 			break;
466 		case AUDIT_PERS:
467 			result = audit_comparator(tsk->personality, f->op, f->val);
468 			break;
469 		case AUDIT_ARCH:
470 			if (ctx)
471 				result = audit_comparator(ctx->arch, f->op, f->val);
472 			break;
473 
474 		case AUDIT_EXIT:
475 			if (ctx && ctx->return_valid)
476 				result = audit_comparator(ctx->return_code, f->op, f->val);
477 			break;
478 		case AUDIT_SUCCESS:
479 			if (ctx && ctx->return_valid) {
480 				if (f->val)
481 					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
482 				else
483 					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
484 			}
485 			break;
486 		case AUDIT_DEVMAJOR:
487 			if (name)
488 				result = audit_comparator(MAJOR(name->dev),
489 							  f->op, f->val);
490 			else if (ctx) {
491 				for (j = 0; j < ctx->name_count; j++) {
492 					if (audit_comparator(MAJOR(ctx->names[j].dev),	f->op, f->val)) {
493 						++result;
494 						break;
495 					}
496 				}
497 			}
498 			break;
499 		case AUDIT_DEVMINOR:
500 			if (name)
501 				result = audit_comparator(MINOR(name->dev),
502 							  f->op, f->val);
503 			else if (ctx) {
504 				for (j = 0; j < ctx->name_count; j++) {
505 					if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) {
506 						++result;
507 						break;
508 					}
509 				}
510 			}
511 			break;
512 		case AUDIT_INODE:
513 			if (name)
514 				result = (name->ino == f->val);
515 			else if (ctx) {
516 				for (j = 0; j < ctx->name_count; j++) {
517 					if (audit_comparator(ctx->names[j].ino, f->op, f->val)) {
518 						++result;
519 						break;
520 					}
521 				}
522 			}
523 			break;
524 		case AUDIT_WATCH:
525 			if (name && rule->watch->ino != (unsigned long)-1)
526 				result = (name->dev == rule->watch->dev &&
527 					  name->ino == rule->watch->ino);
528 			break;
529 		case AUDIT_DIR:
530 			if (ctx)
531 				result = match_tree_refs(ctx, rule->tree);
532 			break;
533 		case AUDIT_LOGINUID:
534 			result = 0;
535 			if (ctx)
536 				result = audit_comparator(tsk->loginuid, f->op, f->val);
537 			break;
538 		case AUDIT_SUBJ_USER:
539 		case AUDIT_SUBJ_ROLE:
540 		case AUDIT_SUBJ_TYPE:
541 		case AUDIT_SUBJ_SEN:
542 		case AUDIT_SUBJ_CLR:
543 			/* NOTE: this may return negative values indicating
544 			   a temporary error.  We simply treat this as a
545 			   match for now to avoid losing information that
546 			   may be wanted.   An error message will also be
547 			   logged upon error */
548 			if (f->lsm_rule) {
549 				if (need_sid) {
550 					security_task_getsecid(tsk, &sid);
551 					need_sid = 0;
552 				}
553 				result = security_audit_rule_match(sid, f->type,
554 				                                  f->op,
555 				                                  f->lsm_rule,
556 				                                  ctx);
557 			}
558 			break;
559 		case AUDIT_OBJ_USER:
560 		case AUDIT_OBJ_ROLE:
561 		case AUDIT_OBJ_TYPE:
562 		case AUDIT_OBJ_LEV_LOW:
563 		case AUDIT_OBJ_LEV_HIGH:
564 			/* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
565 			   also applies here */
566 			if (f->lsm_rule) {
567 				/* Find files that match */
568 				if (name) {
569 					result = security_audit_rule_match(
570 					           name->osid, f->type, f->op,
571 					           f->lsm_rule, ctx);
572 				} else if (ctx) {
573 					for (j = 0; j < ctx->name_count; j++) {
574 						if (security_audit_rule_match(
575 						      ctx->names[j].osid,
576 						      f->type, f->op,
577 						      f->lsm_rule, ctx)) {
578 							++result;
579 							break;
580 						}
581 					}
582 				}
583 				/* Find ipc objects that match */
584 				if (ctx) {
585 					struct audit_aux_data *aux;
586 					for (aux = ctx->aux; aux;
587 					     aux = aux->next) {
588 						if (aux->type == AUDIT_IPC) {
589 							struct audit_aux_data_ipcctl *axi = (void *)aux;
590 							if (security_audit_rule_match(axi->osid, f->type, f->op, f->lsm_rule, ctx)) {
591 								++result;
592 								break;
593 							}
594 						}
595 					}
596 				}
597 			}
598 			break;
599 		case AUDIT_ARG0:
600 		case AUDIT_ARG1:
601 		case AUDIT_ARG2:
602 		case AUDIT_ARG3:
603 			if (ctx)
604 				result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
605 			break;
606 		case AUDIT_FILTERKEY:
607 			/* ignore this field for filtering */
608 			result = 1;
609 			break;
610 		case AUDIT_PERM:
611 			result = audit_match_perm(ctx, f->val);
612 			break;
613 		case AUDIT_FILETYPE:
614 			result = audit_match_filetype(ctx, f->val);
615 			break;
616 		}
617 
618 		if (!result)
619 			return 0;
620 	}
621 	if (rule->filterkey && ctx)
622 		ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
623 	switch (rule->action) {
624 	case AUDIT_NEVER:    *state = AUDIT_DISABLED;	    break;
625 	case AUDIT_ALWAYS:   *state = AUDIT_RECORD_CONTEXT; break;
626 	}
627 	return 1;
628 }
629 
630 /* At process creation time, we can determine if system-call auditing is
631  * completely disabled for this task.  Since we only have the task
632  * structure at this point, we can only check uid and gid.
633  */
634 static enum audit_state audit_filter_task(struct task_struct *tsk)
635 {
636 	struct audit_entry *e;
637 	enum audit_state   state;
638 
639 	rcu_read_lock();
640 	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
641 		if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) {
642 			rcu_read_unlock();
643 			return state;
644 		}
645 	}
646 	rcu_read_unlock();
647 	return AUDIT_BUILD_CONTEXT;
648 }
649 
650 /* At syscall entry and exit time, this filter is called if the
651  * audit_state is not low enough that auditing cannot take place, but is
652  * also not high enough that we already know we have to write an audit
653  * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
654  */
655 static enum audit_state audit_filter_syscall(struct task_struct *tsk,
656 					     struct audit_context *ctx,
657 					     struct list_head *list)
658 {
659 	struct audit_entry *e;
660 	enum audit_state state;
661 
662 	if (audit_pid && tsk->tgid == audit_pid)
663 		return AUDIT_DISABLED;
664 
665 	rcu_read_lock();
666 	if (!list_empty(list)) {
667 		int word = AUDIT_WORD(ctx->major);
668 		int bit  = AUDIT_BIT(ctx->major);
669 
670 		list_for_each_entry_rcu(e, list, list) {
671 			if ((e->rule.mask[word] & bit) == bit &&
672 			    audit_filter_rules(tsk, &e->rule, ctx, NULL,
673 					       &state)) {
674 				rcu_read_unlock();
675 				return state;
676 			}
677 		}
678 	}
679 	rcu_read_unlock();
680 	return AUDIT_BUILD_CONTEXT;
681 }
682 
683 /* At syscall exit time, this filter is called if any audit_names[] have been
684  * collected during syscall processing.  We only check rules in sublists at hash
685  * buckets applicable to the inode numbers in audit_names[].
686  * Regarding audit_state, same rules apply as for audit_filter_syscall().
687  */
688 enum audit_state audit_filter_inodes(struct task_struct *tsk,
689 				     struct audit_context *ctx)
690 {
691 	int i;
692 	struct audit_entry *e;
693 	enum audit_state state;
694 
695 	if (audit_pid && tsk->tgid == audit_pid)
696 		return AUDIT_DISABLED;
697 
698 	rcu_read_lock();
699 	for (i = 0; i < ctx->name_count; i++) {
700 		int word = AUDIT_WORD(ctx->major);
701 		int bit  = AUDIT_BIT(ctx->major);
702 		struct audit_names *n = &ctx->names[i];
703 		int h = audit_hash_ino((u32)n->ino);
704 		struct list_head *list = &audit_inode_hash[h];
705 
706 		if (list_empty(list))
707 			continue;
708 
709 		list_for_each_entry_rcu(e, list, list) {
710 			if ((e->rule.mask[word] & bit) == bit &&
711 			    audit_filter_rules(tsk, &e->rule, ctx, n, &state)) {
712 				rcu_read_unlock();
713 				return state;
714 			}
715 		}
716 	}
717 	rcu_read_unlock();
718 	return AUDIT_BUILD_CONTEXT;
719 }
720 
721 void audit_set_auditable(struct audit_context *ctx)
722 {
723 	ctx->auditable = 1;
724 }
725 
726 static inline struct audit_context *audit_get_context(struct task_struct *tsk,
727 						      int return_valid,
728 						      int return_code)
729 {
730 	struct audit_context *context = tsk->audit_context;
731 
732 	if (likely(!context))
733 		return NULL;
734 	context->return_valid = return_valid;
735 
736 	/*
737 	 * we need to fix up the return code in the audit logs if the actual
738 	 * return codes are later going to be fixed up by the arch specific
739 	 * signal handlers
740 	 *
741 	 * This is actually a test for:
742 	 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
743 	 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
744 	 *
745 	 * but is faster than a bunch of ||
746 	 */
747 	if (unlikely(return_code <= -ERESTARTSYS) &&
748 	    (return_code >= -ERESTART_RESTARTBLOCK) &&
749 	    (return_code != -ENOIOCTLCMD))
750 		context->return_code = -EINTR;
751 	else
752 		context->return_code  = return_code;
753 
754 	if (context->in_syscall && !context->dummy && !context->auditable) {
755 		enum audit_state state;
756 
757 		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
758 		if (state == AUDIT_RECORD_CONTEXT) {
759 			context->auditable = 1;
760 			goto get_context;
761 		}
762 
763 		state = audit_filter_inodes(tsk, context);
764 		if (state == AUDIT_RECORD_CONTEXT)
765 			context->auditable = 1;
766 
767 	}
768 
769 get_context:
770 
771 	tsk->audit_context = NULL;
772 	return context;
773 }
774 
775 static inline void audit_free_names(struct audit_context *context)
776 {
777 	int i;
778 
779 #if AUDIT_DEBUG == 2
780 	if (context->auditable
781 	    ||context->put_count + context->ino_count != context->name_count) {
782 		printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
783 		       " name_count=%d put_count=%d"
784 		       " ino_count=%d [NOT freeing]\n",
785 		       __FILE__, __LINE__,
786 		       context->serial, context->major, context->in_syscall,
787 		       context->name_count, context->put_count,
788 		       context->ino_count);
789 		for (i = 0; i < context->name_count; i++) {
790 			printk(KERN_ERR "names[%d] = %p = %s\n", i,
791 			       context->names[i].name,
792 			       context->names[i].name ?: "(null)");
793 		}
794 		dump_stack();
795 		return;
796 	}
797 #endif
798 #if AUDIT_DEBUG
799 	context->put_count  = 0;
800 	context->ino_count  = 0;
801 #endif
802 
803 	for (i = 0; i < context->name_count; i++) {
804 		if (context->names[i].name && context->names[i].name_put)
805 			__putname(context->names[i].name);
806 	}
807 	context->name_count = 0;
808 	path_put(&context->pwd);
809 	context->pwd.dentry = NULL;
810 	context->pwd.mnt = NULL;
811 }
812 
813 static inline void audit_free_aux(struct audit_context *context)
814 {
815 	struct audit_aux_data *aux;
816 
817 	while ((aux = context->aux)) {
818 		context->aux = aux->next;
819 		kfree(aux);
820 	}
821 	while ((aux = context->aux_pids)) {
822 		context->aux_pids = aux->next;
823 		kfree(aux);
824 	}
825 }
826 
827 static inline void audit_zero_context(struct audit_context *context,
828 				      enum audit_state state)
829 {
830 	memset(context, 0, sizeof(*context));
831 	context->state      = state;
832 }
833 
834 static inline struct audit_context *audit_alloc_context(enum audit_state state)
835 {
836 	struct audit_context *context;
837 
838 	if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
839 		return NULL;
840 	audit_zero_context(context, state);
841 	return context;
842 }
843 
844 /**
845  * audit_alloc - allocate an audit context block for a task
846  * @tsk: task
847  *
848  * Filter on the task information and allocate a per-task audit context
849  * if necessary.  Doing so turns on system call auditing for the
850  * specified task.  This is called from copy_process, so no lock is
851  * needed.
852  */
853 int audit_alloc(struct task_struct *tsk)
854 {
855 	struct audit_context *context;
856 	enum audit_state     state;
857 
858 	if (likely(!audit_ever_enabled))
859 		return 0; /* Return if not auditing. */
860 
861 	state = audit_filter_task(tsk);
862 	if (likely(state == AUDIT_DISABLED))
863 		return 0;
864 
865 	if (!(context = audit_alloc_context(state))) {
866 		audit_log_lost("out of memory in audit_alloc");
867 		return -ENOMEM;
868 	}
869 
870 	tsk->audit_context  = context;
871 	set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
872 	return 0;
873 }
874 
875 static inline void audit_free_context(struct audit_context *context)
876 {
877 	struct audit_context *previous;
878 	int		     count = 0;
879 
880 	do {
881 		previous = context->previous;
882 		if (previous || (count &&  count < 10)) {
883 			++count;
884 			printk(KERN_ERR "audit(:%d): major=%d name_count=%d:"
885 			       " freeing multiple contexts (%d)\n",
886 			       context->serial, context->major,
887 			       context->name_count, count);
888 		}
889 		audit_free_names(context);
890 		unroll_tree_refs(context, NULL, 0);
891 		free_tree_refs(context);
892 		audit_free_aux(context);
893 		kfree(context->filterkey);
894 		kfree(context);
895 		context  = previous;
896 	} while (context);
897 	if (count >= 10)
898 		printk(KERN_ERR "audit: freed %d contexts\n", count);
899 }
900 
901 void audit_log_task_context(struct audit_buffer *ab)
902 {
903 	char *ctx = NULL;
904 	unsigned len;
905 	int error;
906 	u32 sid;
907 
908 	security_task_getsecid(current, &sid);
909 	if (!sid)
910 		return;
911 
912 	error = security_secid_to_secctx(sid, &ctx, &len);
913 	if (error) {
914 		if (error != -EINVAL)
915 			goto error_path;
916 		return;
917 	}
918 
919 	audit_log_format(ab, " subj=%s", ctx);
920 	security_release_secctx(ctx, len);
921 	return;
922 
923 error_path:
924 	audit_panic("error in audit_log_task_context");
925 	return;
926 }
927 
928 EXPORT_SYMBOL(audit_log_task_context);
929 
930 static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
931 {
932 	char name[sizeof(tsk->comm)];
933 	struct mm_struct *mm = tsk->mm;
934 	struct vm_area_struct *vma;
935 
936 	/* tsk == current */
937 
938 	get_task_comm(name, tsk);
939 	audit_log_format(ab, " comm=");
940 	audit_log_untrustedstring(ab, name);
941 
942 	if (mm) {
943 		down_read(&mm->mmap_sem);
944 		vma = mm->mmap;
945 		while (vma) {
946 			if ((vma->vm_flags & VM_EXECUTABLE) &&
947 			    vma->vm_file) {
948 				audit_log_d_path(ab, "exe=",
949 						 &vma->vm_file->f_path);
950 				break;
951 			}
952 			vma = vma->vm_next;
953 		}
954 		up_read(&mm->mmap_sem);
955 	}
956 	audit_log_task_context(ab);
957 }
958 
959 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
960 				 uid_t auid, uid_t uid, unsigned int sessionid,
961 				 u32 sid, char *comm)
962 {
963 	struct audit_buffer *ab;
964 	char *ctx = NULL;
965 	u32 len;
966 	int rc = 0;
967 
968 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
969 	if (!ab)
970 		return rc;
971 
972 	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid,
973 			 uid, sessionid);
974 	if (security_secid_to_secctx(sid, &ctx, &len)) {
975 		audit_log_format(ab, " obj=(none)");
976 		rc = 1;
977 	} else {
978 		audit_log_format(ab, " obj=%s", ctx);
979 		security_release_secctx(ctx, len);
980 	}
981 	audit_log_format(ab, " ocomm=");
982 	audit_log_untrustedstring(ab, comm);
983 	audit_log_end(ab);
984 
985 	return rc;
986 }
987 
988 /*
989  * to_send and len_sent accounting are very loose estimates.  We aren't
990  * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being
991  * within about 500 bytes (next page boundry)
992  *
993  * why snprintf?  an int is up to 12 digits long.  if we just assumed when
994  * logging that a[%d]= was going to be 16 characters long we would be wasting
995  * space in every audit message.  In one 7500 byte message we can log up to
996  * about 1000 min size arguments.  That comes down to about 50% waste of space
997  * if we didn't do the snprintf to find out how long arg_num_len was.
998  */
999 static int audit_log_single_execve_arg(struct audit_context *context,
1000 					struct audit_buffer **ab,
1001 					int arg_num,
1002 					size_t *len_sent,
1003 					const char __user *p,
1004 					char *buf)
1005 {
1006 	char arg_num_len_buf[12];
1007 	const char __user *tmp_p = p;
1008 	/* how many digits are in arg_num? 3 is the length of a=\n */
1009 	size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 3;
1010 	size_t len, len_left, to_send;
1011 	size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN;
1012 	unsigned int i, has_cntl = 0, too_long = 0;
1013 	int ret;
1014 
1015 	/* strnlen_user includes the null we don't want to send */
1016 	len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1017 
1018 	/*
1019 	 * We just created this mm, if we can't find the strings
1020 	 * we just copied into it something is _very_ wrong. Similar
1021 	 * for strings that are too long, we should not have created
1022 	 * any.
1023 	 */
1024 	if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
1025 		WARN_ON(1);
1026 		send_sig(SIGKILL, current, 0);
1027 		return -1;
1028 	}
1029 
1030 	/* walk the whole argument looking for non-ascii chars */
1031 	do {
1032 		if (len_left > MAX_EXECVE_AUDIT_LEN)
1033 			to_send = MAX_EXECVE_AUDIT_LEN;
1034 		else
1035 			to_send = len_left;
1036 		ret = copy_from_user(buf, tmp_p, to_send);
1037 		/*
1038 		 * There is no reason for this copy to be short. We just
1039 		 * copied them here, and the mm hasn't been exposed to user-
1040 		 * space yet.
1041 		 */
1042 		if (ret) {
1043 			WARN_ON(1);
1044 			send_sig(SIGKILL, current, 0);
1045 			return -1;
1046 		}
1047 		buf[to_send] = '\0';
1048 		has_cntl = audit_string_contains_control(buf, to_send);
1049 		if (has_cntl) {
1050 			/*
1051 			 * hex messages get logged as 2 bytes, so we can only
1052 			 * send half as much in each message
1053 			 */
1054 			max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2;
1055 			break;
1056 		}
1057 		len_left -= to_send;
1058 		tmp_p += to_send;
1059 	} while (len_left > 0);
1060 
1061 	len_left = len;
1062 
1063 	if (len > max_execve_audit_len)
1064 		too_long = 1;
1065 
1066 	/* rewalk the argument actually logging the message */
1067 	for (i = 0; len_left > 0; i++) {
1068 		int room_left;
1069 
1070 		if (len_left > max_execve_audit_len)
1071 			to_send = max_execve_audit_len;
1072 		else
1073 			to_send = len_left;
1074 
1075 		/* do we have space left to send this argument in this ab? */
1076 		room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent;
1077 		if (has_cntl)
1078 			room_left -= (to_send * 2);
1079 		else
1080 			room_left -= to_send;
1081 		if (room_left < 0) {
1082 			*len_sent = 0;
1083 			audit_log_end(*ab);
1084 			*ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE);
1085 			if (!*ab)
1086 				return 0;
1087 		}
1088 
1089 		/*
1090 		 * first record needs to say how long the original string was
1091 		 * so we can be sure nothing was lost.
1092 		 */
1093 		if ((i == 0) && (too_long))
1094 			audit_log_format(*ab, "a%d_len=%zu ", arg_num,
1095 					 has_cntl ? 2*len : len);
1096 
1097 		/*
1098 		 * normally arguments are small enough to fit and we already
1099 		 * filled buf above when we checked for control characters
1100 		 * so don't bother with another copy_from_user
1101 		 */
1102 		if (len >= max_execve_audit_len)
1103 			ret = copy_from_user(buf, p, to_send);
1104 		else
1105 			ret = 0;
1106 		if (ret) {
1107 			WARN_ON(1);
1108 			send_sig(SIGKILL, current, 0);
1109 			return -1;
1110 		}
1111 		buf[to_send] = '\0';
1112 
1113 		/* actually log it */
1114 		audit_log_format(*ab, "a%d", arg_num);
1115 		if (too_long)
1116 			audit_log_format(*ab, "[%d]", i);
1117 		audit_log_format(*ab, "=");
1118 		if (has_cntl)
1119 			audit_log_n_hex(*ab, buf, to_send);
1120 		else
1121 			audit_log_format(*ab, "\"%s\"", buf);
1122 		audit_log_format(*ab, "\n");
1123 
1124 		p += to_send;
1125 		len_left -= to_send;
1126 		*len_sent += arg_num_len;
1127 		if (has_cntl)
1128 			*len_sent += to_send * 2;
1129 		else
1130 			*len_sent += to_send;
1131 	}
1132 	/* include the null we didn't log */
1133 	return len + 1;
1134 }
1135 
1136 static void audit_log_execve_info(struct audit_context *context,
1137 				  struct audit_buffer **ab,
1138 				  struct audit_aux_data_execve *axi)
1139 {
1140 	int i;
1141 	size_t len, len_sent = 0;
1142 	const char __user *p;
1143 	char *buf;
1144 
1145 	if (axi->mm != current->mm)
1146 		return; /* execve failed, no additional info */
1147 
1148 	p = (const char __user *)axi->mm->arg_start;
1149 
1150 	audit_log_format(*ab, "argc=%d ", axi->argc);
1151 
1152 	/*
1153 	 * we need some kernel buffer to hold the userspace args.  Just
1154 	 * allocate one big one rather than allocating one of the right size
1155 	 * for every single argument inside audit_log_single_execve_arg()
1156 	 * should be <8k allocation so should be pretty safe.
1157 	 */
1158 	buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1159 	if (!buf) {
1160 		audit_panic("out of memory for argv string\n");
1161 		return;
1162 	}
1163 
1164 	for (i = 0; i < axi->argc; i++) {
1165 		len = audit_log_single_execve_arg(context, ab, i,
1166 						  &len_sent, p, buf);
1167 		if (len <= 0)
1168 			break;
1169 		p += len;
1170 	}
1171 	kfree(buf);
1172 }
1173 
1174 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
1175 {
1176 	int i, call_panic = 0;
1177 	struct audit_buffer *ab;
1178 	struct audit_aux_data *aux;
1179 	const char *tty;
1180 
1181 	/* tsk == current */
1182 	context->pid = tsk->pid;
1183 	if (!context->ppid)
1184 		context->ppid = sys_getppid();
1185 	context->uid = tsk->uid;
1186 	context->gid = tsk->gid;
1187 	context->euid = tsk->euid;
1188 	context->suid = tsk->suid;
1189 	context->fsuid = tsk->fsuid;
1190 	context->egid = tsk->egid;
1191 	context->sgid = tsk->sgid;
1192 	context->fsgid = tsk->fsgid;
1193 	context->personality = tsk->personality;
1194 
1195 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1196 	if (!ab)
1197 		return;		/* audit_panic has been called */
1198 	audit_log_format(ab, "arch=%x syscall=%d",
1199 			 context->arch, context->major);
1200 	if (context->personality != PER_LINUX)
1201 		audit_log_format(ab, " per=%lx", context->personality);
1202 	if (context->return_valid)
1203 		audit_log_format(ab, " success=%s exit=%ld",
1204 				 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
1205 				 context->return_code);
1206 
1207 	spin_lock_irq(&tsk->sighand->siglock);
1208 	if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
1209 		tty = tsk->signal->tty->name;
1210 	else
1211 		tty = "(none)";
1212 	spin_unlock_irq(&tsk->sighand->siglock);
1213 
1214 	audit_log_format(ab,
1215 		  " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
1216 		  " ppid=%d pid=%d auid=%u uid=%u gid=%u"
1217 		  " euid=%u suid=%u fsuid=%u"
1218 		  " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
1219 		  context->argv[0],
1220 		  context->argv[1],
1221 		  context->argv[2],
1222 		  context->argv[3],
1223 		  context->name_count,
1224 		  context->ppid,
1225 		  context->pid,
1226 		  tsk->loginuid,
1227 		  context->uid,
1228 		  context->gid,
1229 		  context->euid, context->suid, context->fsuid,
1230 		  context->egid, context->sgid, context->fsgid, tty,
1231 		  tsk->sessionid);
1232 
1233 
1234 	audit_log_task_info(ab, tsk);
1235 	if (context->filterkey) {
1236 		audit_log_format(ab, " key=");
1237 		audit_log_untrustedstring(ab, context->filterkey);
1238 	} else
1239 		audit_log_format(ab, " key=(null)");
1240 	audit_log_end(ab);
1241 
1242 	for (aux = context->aux; aux; aux = aux->next) {
1243 
1244 		ab = audit_log_start(context, GFP_KERNEL, aux->type);
1245 		if (!ab)
1246 			continue; /* audit_panic has been called */
1247 
1248 		switch (aux->type) {
1249 		case AUDIT_MQ_OPEN: {
1250 			struct audit_aux_data_mq_open *axi = (void *)aux;
1251 			audit_log_format(ab,
1252 				"oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld "
1253 				"mq_msgsize=%ld mq_curmsgs=%ld",
1254 				axi->oflag, axi->mode, axi->attr.mq_flags,
1255 				axi->attr.mq_maxmsg, axi->attr.mq_msgsize,
1256 				axi->attr.mq_curmsgs);
1257 			break; }
1258 
1259 		case AUDIT_MQ_SENDRECV: {
1260 			struct audit_aux_data_mq_sendrecv *axi = (void *)aux;
1261 			audit_log_format(ab,
1262 				"mqdes=%d msg_len=%zd msg_prio=%u "
1263 				"abs_timeout_sec=%ld abs_timeout_nsec=%ld",
1264 				axi->mqdes, axi->msg_len, axi->msg_prio,
1265 				axi->abs_timeout.tv_sec, axi->abs_timeout.tv_nsec);
1266 			break; }
1267 
1268 		case AUDIT_MQ_NOTIFY: {
1269 			struct audit_aux_data_mq_notify *axi = (void *)aux;
1270 			audit_log_format(ab,
1271 				"mqdes=%d sigev_signo=%d",
1272 				axi->mqdes,
1273 				axi->notification.sigev_signo);
1274 			break; }
1275 
1276 		case AUDIT_MQ_GETSETATTR: {
1277 			struct audit_aux_data_mq_getsetattr *axi = (void *)aux;
1278 			audit_log_format(ab,
1279 				"mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1280 				"mq_curmsgs=%ld ",
1281 				axi->mqdes,
1282 				axi->mqstat.mq_flags, axi->mqstat.mq_maxmsg,
1283 				axi->mqstat.mq_msgsize, axi->mqstat.mq_curmsgs);
1284 			break; }
1285 
1286 		case AUDIT_IPC: {
1287 			struct audit_aux_data_ipcctl *axi = (void *)aux;
1288 			audit_log_format(ab,
1289 				 "ouid=%u ogid=%u mode=%#o",
1290 				 axi->uid, axi->gid, axi->mode);
1291 			if (axi->osid != 0) {
1292 				char *ctx = NULL;
1293 				u32 len;
1294 				if (security_secid_to_secctx(
1295 						axi->osid, &ctx, &len)) {
1296 					audit_log_format(ab, " osid=%u",
1297 							axi->osid);
1298 					call_panic = 1;
1299 				} else {
1300 					audit_log_format(ab, " obj=%s", ctx);
1301 					security_release_secctx(ctx, len);
1302 				}
1303 			}
1304 			break; }
1305 
1306 		case AUDIT_IPC_SET_PERM: {
1307 			struct audit_aux_data_ipcctl *axi = (void *)aux;
1308 			audit_log_format(ab,
1309 				"qbytes=%lx ouid=%u ogid=%u mode=%#o",
1310 				axi->qbytes, axi->uid, axi->gid, axi->mode);
1311 			break; }
1312 
1313 		case AUDIT_EXECVE: {
1314 			struct audit_aux_data_execve *axi = (void *)aux;
1315 			audit_log_execve_info(context, &ab, axi);
1316 			break; }
1317 
1318 		case AUDIT_SOCKETCALL: {
1319 			struct audit_aux_data_socketcall *axs = (void *)aux;
1320 			audit_log_format(ab, "nargs=%d", axs->nargs);
1321 			for (i=0; i<axs->nargs; i++)
1322 				audit_log_format(ab, " a%d=%lx", i, axs->args[i]);
1323 			break; }
1324 
1325 		case AUDIT_SOCKADDR: {
1326 			struct audit_aux_data_sockaddr *axs = (void *)aux;
1327 
1328 			audit_log_format(ab, "saddr=");
1329 			audit_log_n_hex(ab, axs->a, axs->len);
1330 			break; }
1331 
1332 		case AUDIT_FD_PAIR: {
1333 			struct audit_aux_data_fd_pair *axs = (void *)aux;
1334 			audit_log_format(ab, "fd0=%d fd1=%d", axs->fd[0], axs->fd[1]);
1335 			break; }
1336 
1337 		}
1338 		audit_log_end(ab);
1339 	}
1340 
1341 	for (aux = context->aux_pids; aux; aux = aux->next) {
1342 		struct audit_aux_data_pids *axs = (void *)aux;
1343 
1344 		for (i = 0; i < axs->pid_count; i++)
1345 			if (audit_log_pid_context(context, axs->target_pid[i],
1346 						  axs->target_auid[i],
1347 						  axs->target_uid[i],
1348 						  axs->target_sessionid[i],
1349 						  axs->target_sid[i],
1350 						  axs->target_comm[i]))
1351 				call_panic = 1;
1352 	}
1353 
1354 	if (context->target_pid &&
1355 	    audit_log_pid_context(context, context->target_pid,
1356 				  context->target_auid, context->target_uid,
1357 				  context->target_sessionid,
1358 				  context->target_sid, context->target_comm))
1359 			call_panic = 1;
1360 
1361 	if (context->pwd.dentry && context->pwd.mnt) {
1362 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1363 		if (ab) {
1364 			audit_log_d_path(ab, "cwd=", &context->pwd);
1365 			audit_log_end(ab);
1366 		}
1367 	}
1368 	for (i = 0; i < context->name_count; i++) {
1369 		struct audit_names *n = &context->names[i];
1370 
1371 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1372 		if (!ab)
1373 			continue; /* audit_panic has been called */
1374 
1375 		audit_log_format(ab, "item=%d", i);
1376 
1377 		if (n->name) {
1378 			switch(n->name_len) {
1379 			case AUDIT_NAME_FULL:
1380 				/* log the full path */
1381 				audit_log_format(ab, " name=");
1382 				audit_log_untrustedstring(ab, n->name);
1383 				break;
1384 			case 0:
1385 				/* name was specified as a relative path and the
1386 				 * directory component is the cwd */
1387 				audit_log_d_path(ab, " name=", &context->pwd);
1388 				break;
1389 			default:
1390 				/* log the name's directory component */
1391 				audit_log_format(ab, " name=");
1392 				audit_log_n_untrustedstring(ab, n->name,
1393 							    n->name_len);
1394 			}
1395 		} else
1396 			audit_log_format(ab, " name=(null)");
1397 
1398 		if (n->ino != (unsigned long)-1) {
1399 			audit_log_format(ab, " inode=%lu"
1400 					 " dev=%02x:%02x mode=%#o"
1401 					 " ouid=%u ogid=%u rdev=%02x:%02x",
1402 					 n->ino,
1403 					 MAJOR(n->dev),
1404 					 MINOR(n->dev),
1405 					 n->mode,
1406 					 n->uid,
1407 					 n->gid,
1408 					 MAJOR(n->rdev),
1409 					 MINOR(n->rdev));
1410 		}
1411 		if (n->osid != 0) {
1412 			char *ctx = NULL;
1413 			u32 len;
1414 			if (security_secid_to_secctx(
1415 				n->osid, &ctx, &len)) {
1416 				audit_log_format(ab, " osid=%u", n->osid);
1417 				call_panic = 2;
1418 			} else {
1419 				audit_log_format(ab, " obj=%s", ctx);
1420 				security_release_secctx(ctx, len);
1421 			}
1422 		}
1423 
1424 		audit_log_end(ab);
1425 	}
1426 
1427 	/* Send end of event record to help user space know we are finished */
1428 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1429 	if (ab)
1430 		audit_log_end(ab);
1431 	if (call_panic)
1432 		audit_panic("error converting sid to string");
1433 }
1434 
1435 /**
1436  * audit_free - free a per-task audit context
1437  * @tsk: task whose audit context block to free
1438  *
1439  * Called from copy_process and do_exit
1440  */
1441 void audit_free(struct task_struct *tsk)
1442 {
1443 	struct audit_context *context;
1444 
1445 	context = audit_get_context(tsk, 0, 0);
1446 	if (likely(!context))
1447 		return;
1448 
1449 	/* Check for system calls that do not go through the exit
1450 	 * function (e.g., exit_group), then free context block.
1451 	 * We use GFP_ATOMIC here because we might be doing this
1452 	 * in the context of the idle thread */
1453 	/* that can happen only if we are called from do_exit() */
1454 	if (context->in_syscall && context->auditable)
1455 		audit_log_exit(context, tsk);
1456 
1457 	audit_free_context(context);
1458 }
1459 
1460 /**
1461  * audit_syscall_entry - fill in an audit record at syscall entry
1462  * @tsk: task being audited
1463  * @arch: architecture type
1464  * @major: major syscall type (function)
1465  * @a1: additional syscall register 1
1466  * @a2: additional syscall register 2
1467  * @a3: additional syscall register 3
1468  * @a4: additional syscall register 4
1469  *
1470  * Fill in audit context at syscall entry.  This only happens if the
1471  * audit context was created when the task was created and the state or
1472  * filters demand the audit context be built.  If the state from the
1473  * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1474  * then the record will be written at syscall exit time (otherwise, it
1475  * will only be written if another part of the kernel requests that it
1476  * be written).
1477  */
1478 void audit_syscall_entry(int arch, int major,
1479 			 unsigned long a1, unsigned long a2,
1480 			 unsigned long a3, unsigned long a4)
1481 {
1482 	struct task_struct *tsk = current;
1483 	struct audit_context *context = tsk->audit_context;
1484 	enum audit_state     state;
1485 
1486 	if (unlikely(!context))
1487 		return;
1488 
1489 	/*
1490 	 * This happens only on certain architectures that make system
1491 	 * calls in kernel_thread via the entry.S interface, instead of
1492 	 * with direct calls.  (If you are porting to a new
1493 	 * architecture, hitting this condition can indicate that you
1494 	 * got the _exit/_leave calls backward in entry.S.)
1495 	 *
1496 	 * i386     no
1497 	 * x86_64   no
1498 	 * ppc64    yes (see arch/powerpc/platforms/iseries/misc.S)
1499 	 *
1500 	 * This also happens with vm86 emulation in a non-nested manner
1501 	 * (entries without exits), so this case must be caught.
1502 	 */
1503 	if (context->in_syscall) {
1504 		struct audit_context *newctx;
1505 
1506 #if AUDIT_DEBUG
1507 		printk(KERN_ERR
1508 		       "audit(:%d) pid=%d in syscall=%d;"
1509 		       " entering syscall=%d\n",
1510 		       context->serial, tsk->pid, context->major, major);
1511 #endif
1512 		newctx = audit_alloc_context(context->state);
1513 		if (newctx) {
1514 			newctx->previous   = context;
1515 			context		   = newctx;
1516 			tsk->audit_context = newctx;
1517 		} else	{
1518 			/* If we can't alloc a new context, the best we
1519 			 * can do is to leak memory (any pending putname
1520 			 * will be lost).  The only other alternative is
1521 			 * to abandon auditing. */
1522 			audit_zero_context(context, context->state);
1523 		}
1524 	}
1525 	BUG_ON(context->in_syscall || context->name_count);
1526 
1527 	if (!audit_enabled)
1528 		return;
1529 
1530 	context->arch	    = arch;
1531 	context->major      = major;
1532 	context->argv[0]    = a1;
1533 	context->argv[1]    = a2;
1534 	context->argv[2]    = a3;
1535 	context->argv[3]    = a4;
1536 
1537 	state = context->state;
1538 	context->dummy = !audit_n_rules;
1539 	if (!context->dummy && (state == AUDIT_SETUP_CONTEXT || state == AUDIT_BUILD_CONTEXT))
1540 		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1541 	if (likely(state == AUDIT_DISABLED))
1542 		return;
1543 
1544 	context->serial     = 0;
1545 	context->ctime      = CURRENT_TIME;
1546 	context->in_syscall = 1;
1547 	context->auditable  = !!(state == AUDIT_RECORD_CONTEXT);
1548 	context->ppid       = 0;
1549 }
1550 
1551 /**
1552  * audit_syscall_exit - deallocate audit context after a system call
1553  * @tsk: task being audited
1554  * @valid: success/failure flag
1555  * @return_code: syscall return value
1556  *
1557  * Tear down after system call.  If the audit context has been marked as
1558  * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1559  * filtering, or because some other part of the kernel write an audit
1560  * message), then write out the syscall information.  In call cases,
1561  * free the names stored from getname().
1562  */
1563 void audit_syscall_exit(int valid, long return_code)
1564 {
1565 	struct task_struct *tsk = current;
1566 	struct audit_context *context;
1567 
1568 	context = audit_get_context(tsk, valid, return_code);
1569 
1570 	if (likely(!context))
1571 		return;
1572 
1573 	if (context->in_syscall && context->auditable)
1574 		audit_log_exit(context, tsk);
1575 
1576 	context->in_syscall = 0;
1577 	context->auditable  = 0;
1578 
1579 	if (context->previous) {
1580 		struct audit_context *new_context = context->previous;
1581 		context->previous  = NULL;
1582 		audit_free_context(context);
1583 		tsk->audit_context = new_context;
1584 	} else {
1585 		audit_free_names(context);
1586 		unroll_tree_refs(context, NULL, 0);
1587 		audit_free_aux(context);
1588 		context->aux = NULL;
1589 		context->aux_pids = NULL;
1590 		context->target_pid = 0;
1591 		context->target_sid = 0;
1592 		kfree(context->filterkey);
1593 		context->filterkey = NULL;
1594 		tsk->audit_context = context;
1595 	}
1596 }
1597 
1598 static inline void handle_one(const struct inode *inode)
1599 {
1600 #ifdef CONFIG_AUDIT_TREE
1601 	struct audit_context *context;
1602 	struct audit_tree_refs *p;
1603 	struct audit_chunk *chunk;
1604 	int count;
1605 	if (likely(list_empty(&inode->inotify_watches)))
1606 		return;
1607 	context = current->audit_context;
1608 	p = context->trees;
1609 	count = context->tree_count;
1610 	rcu_read_lock();
1611 	chunk = audit_tree_lookup(inode);
1612 	rcu_read_unlock();
1613 	if (!chunk)
1614 		return;
1615 	if (likely(put_tree_ref(context, chunk)))
1616 		return;
1617 	if (unlikely(!grow_tree_refs(context))) {
1618 		printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
1619 		audit_set_auditable(context);
1620 		audit_put_chunk(chunk);
1621 		unroll_tree_refs(context, p, count);
1622 		return;
1623 	}
1624 	put_tree_ref(context, chunk);
1625 #endif
1626 }
1627 
1628 static void handle_path(const struct dentry *dentry)
1629 {
1630 #ifdef CONFIG_AUDIT_TREE
1631 	struct audit_context *context;
1632 	struct audit_tree_refs *p;
1633 	const struct dentry *d, *parent;
1634 	struct audit_chunk *drop;
1635 	unsigned long seq;
1636 	int count;
1637 
1638 	context = current->audit_context;
1639 	p = context->trees;
1640 	count = context->tree_count;
1641 retry:
1642 	drop = NULL;
1643 	d = dentry;
1644 	rcu_read_lock();
1645 	seq = read_seqbegin(&rename_lock);
1646 	for(;;) {
1647 		struct inode *inode = d->d_inode;
1648 		if (inode && unlikely(!list_empty(&inode->inotify_watches))) {
1649 			struct audit_chunk *chunk;
1650 			chunk = audit_tree_lookup(inode);
1651 			if (chunk) {
1652 				if (unlikely(!put_tree_ref(context, chunk))) {
1653 					drop = chunk;
1654 					break;
1655 				}
1656 			}
1657 		}
1658 		parent = d->d_parent;
1659 		if (parent == d)
1660 			break;
1661 		d = parent;
1662 	}
1663 	if (unlikely(read_seqretry(&rename_lock, seq) || drop)) {  /* in this order */
1664 		rcu_read_unlock();
1665 		if (!drop) {
1666 			/* just a race with rename */
1667 			unroll_tree_refs(context, p, count);
1668 			goto retry;
1669 		}
1670 		audit_put_chunk(drop);
1671 		if (grow_tree_refs(context)) {
1672 			/* OK, got more space */
1673 			unroll_tree_refs(context, p, count);
1674 			goto retry;
1675 		}
1676 		/* too bad */
1677 		printk(KERN_WARNING
1678 			"out of memory, audit has lost a tree reference\n");
1679 		unroll_tree_refs(context, p, count);
1680 		audit_set_auditable(context);
1681 		return;
1682 	}
1683 	rcu_read_unlock();
1684 #endif
1685 }
1686 
1687 /**
1688  * audit_getname - add a name to the list
1689  * @name: name to add
1690  *
1691  * Add a name to the list of audit names for this context.
1692  * Called from fs/namei.c:getname().
1693  */
1694 void __audit_getname(const char *name)
1695 {
1696 	struct audit_context *context = current->audit_context;
1697 
1698 	if (IS_ERR(name) || !name)
1699 		return;
1700 
1701 	if (!context->in_syscall) {
1702 #if AUDIT_DEBUG == 2
1703 		printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
1704 		       __FILE__, __LINE__, context->serial, name);
1705 		dump_stack();
1706 #endif
1707 		return;
1708 	}
1709 	BUG_ON(context->name_count >= AUDIT_NAMES);
1710 	context->names[context->name_count].name = name;
1711 	context->names[context->name_count].name_len = AUDIT_NAME_FULL;
1712 	context->names[context->name_count].name_put = 1;
1713 	context->names[context->name_count].ino  = (unsigned long)-1;
1714 	context->names[context->name_count].osid = 0;
1715 	++context->name_count;
1716 	if (!context->pwd.dentry) {
1717 		read_lock(&current->fs->lock);
1718 		context->pwd = current->fs->pwd;
1719 		path_get(&current->fs->pwd);
1720 		read_unlock(&current->fs->lock);
1721 	}
1722 
1723 }
1724 
1725 /* audit_putname - intercept a putname request
1726  * @name: name to intercept and delay for putname
1727  *
1728  * If we have stored the name from getname in the audit context,
1729  * then we delay the putname until syscall exit.
1730  * Called from include/linux/fs.h:putname().
1731  */
1732 void audit_putname(const char *name)
1733 {
1734 	struct audit_context *context = current->audit_context;
1735 
1736 	BUG_ON(!context);
1737 	if (!context->in_syscall) {
1738 #if AUDIT_DEBUG == 2
1739 		printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n",
1740 		       __FILE__, __LINE__, context->serial, name);
1741 		if (context->name_count) {
1742 			int i;
1743 			for (i = 0; i < context->name_count; i++)
1744 				printk(KERN_ERR "name[%d] = %p = %s\n", i,
1745 				       context->names[i].name,
1746 				       context->names[i].name ?: "(null)");
1747 		}
1748 #endif
1749 		__putname(name);
1750 	}
1751 #if AUDIT_DEBUG
1752 	else {
1753 		++context->put_count;
1754 		if (context->put_count > context->name_count) {
1755 			printk(KERN_ERR "%s:%d(:%d): major=%d"
1756 			       " in_syscall=%d putname(%p) name_count=%d"
1757 			       " put_count=%d\n",
1758 			       __FILE__, __LINE__,
1759 			       context->serial, context->major,
1760 			       context->in_syscall, name, context->name_count,
1761 			       context->put_count);
1762 			dump_stack();
1763 		}
1764 	}
1765 #endif
1766 }
1767 
1768 static int audit_inc_name_count(struct audit_context *context,
1769 				const struct inode *inode)
1770 {
1771 	if (context->name_count >= AUDIT_NAMES) {
1772 		if (inode)
1773 			printk(KERN_DEBUG "name_count maxed, losing inode data: "
1774 			       "dev=%02x:%02x, inode=%lu\n",
1775 			       MAJOR(inode->i_sb->s_dev),
1776 			       MINOR(inode->i_sb->s_dev),
1777 			       inode->i_ino);
1778 
1779 		else
1780 			printk(KERN_DEBUG "name_count maxed, losing inode data\n");
1781 		return 1;
1782 	}
1783 	context->name_count++;
1784 #if AUDIT_DEBUG
1785 	context->ino_count++;
1786 #endif
1787 	return 0;
1788 }
1789 
1790 /* Copy inode data into an audit_names. */
1791 static void audit_copy_inode(struct audit_names *name, const struct inode *inode)
1792 {
1793 	name->ino   = inode->i_ino;
1794 	name->dev   = inode->i_sb->s_dev;
1795 	name->mode  = inode->i_mode;
1796 	name->uid   = inode->i_uid;
1797 	name->gid   = inode->i_gid;
1798 	name->rdev  = inode->i_rdev;
1799 	security_inode_getsecid(inode, &name->osid);
1800 }
1801 
1802 /**
1803  * audit_inode - store the inode and device from a lookup
1804  * @name: name being audited
1805  * @dentry: dentry being audited
1806  *
1807  * Called from fs/namei.c:path_lookup().
1808  */
1809 void __audit_inode(const char *name, const struct dentry *dentry)
1810 {
1811 	int idx;
1812 	struct audit_context *context = current->audit_context;
1813 	const struct inode *inode = dentry->d_inode;
1814 
1815 	if (!context->in_syscall)
1816 		return;
1817 	if (context->name_count
1818 	    && context->names[context->name_count-1].name
1819 	    && context->names[context->name_count-1].name == name)
1820 		idx = context->name_count - 1;
1821 	else if (context->name_count > 1
1822 		 && context->names[context->name_count-2].name
1823 		 && context->names[context->name_count-2].name == name)
1824 		idx = context->name_count - 2;
1825 	else {
1826 		/* FIXME: how much do we care about inodes that have no
1827 		 * associated name? */
1828 		if (audit_inc_name_count(context, inode))
1829 			return;
1830 		idx = context->name_count - 1;
1831 		context->names[idx].name = NULL;
1832 	}
1833 	handle_path(dentry);
1834 	audit_copy_inode(&context->names[idx], inode);
1835 }
1836 
1837 /**
1838  * audit_inode_child - collect inode info for created/removed objects
1839  * @dname: inode's dentry name
1840  * @dentry: dentry being audited
1841  * @parent: inode of dentry parent
1842  *
1843  * For syscalls that create or remove filesystem objects, audit_inode
1844  * can only collect information for the filesystem object's parent.
1845  * This call updates the audit context with the child's information.
1846  * Syscalls that create a new filesystem object must be hooked after
1847  * the object is created.  Syscalls that remove a filesystem object
1848  * must be hooked prior, in order to capture the target inode during
1849  * unsuccessful attempts.
1850  */
1851 void __audit_inode_child(const char *dname, const struct dentry *dentry,
1852 			 const struct inode *parent)
1853 {
1854 	int idx;
1855 	struct audit_context *context = current->audit_context;
1856 	const char *found_parent = NULL, *found_child = NULL;
1857 	const struct inode *inode = dentry->d_inode;
1858 	int dirlen = 0;
1859 
1860 	if (!context->in_syscall)
1861 		return;
1862 
1863 	if (inode)
1864 		handle_one(inode);
1865 	/* determine matching parent */
1866 	if (!dname)
1867 		goto add_names;
1868 
1869 	/* parent is more likely, look for it first */
1870 	for (idx = 0; idx < context->name_count; idx++) {
1871 		struct audit_names *n = &context->names[idx];
1872 
1873 		if (!n->name)
1874 			continue;
1875 
1876 		if (n->ino == parent->i_ino &&
1877 		    !audit_compare_dname_path(dname, n->name, &dirlen)) {
1878 			n->name_len = dirlen; /* update parent data in place */
1879 			found_parent = n->name;
1880 			goto add_names;
1881 		}
1882 	}
1883 
1884 	/* no matching parent, look for matching child */
1885 	for (idx = 0; idx < context->name_count; idx++) {
1886 		struct audit_names *n = &context->names[idx];
1887 
1888 		if (!n->name)
1889 			continue;
1890 
1891 		/* strcmp() is the more likely scenario */
1892 		if (!strcmp(dname, n->name) ||
1893 		     !audit_compare_dname_path(dname, n->name, &dirlen)) {
1894 			if (inode)
1895 				audit_copy_inode(n, inode);
1896 			else
1897 				n->ino = (unsigned long)-1;
1898 			found_child = n->name;
1899 			goto add_names;
1900 		}
1901 	}
1902 
1903 add_names:
1904 	if (!found_parent) {
1905 		if (audit_inc_name_count(context, parent))
1906 			return;
1907 		idx = context->name_count - 1;
1908 		context->names[idx].name = NULL;
1909 		audit_copy_inode(&context->names[idx], parent);
1910 	}
1911 
1912 	if (!found_child) {
1913 		if (audit_inc_name_count(context, inode))
1914 			return;
1915 		idx = context->name_count - 1;
1916 
1917 		/* Re-use the name belonging to the slot for a matching parent
1918 		 * directory. All names for this context are relinquished in
1919 		 * audit_free_names() */
1920 		if (found_parent) {
1921 			context->names[idx].name = found_parent;
1922 			context->names[idx].name_len = AUDIT_NAME_FULL;
1923 			/* don't call __putname() */
1924 			context->names[idx].name_put = 0;
1925 		} else {
1926 			context->names[idx].name = NULL;
1927 		}
1928 
1929 		if (inode)
1930 			audit_copy_inode(&context->names[idx], inode);
1931 		else
1932 			context->names[idx].ino = (unsigned long)-1;
1933 	}
1934 }
1935 EXPORT_SYMBOL_GPL(__audit_inode_child);
1936 
1937 /**
1938  * auditsc_get_stamp - get local copies of audit_context values
1939  * @ctx: audit_context for the task
1940  * @t: timespec to store time recorded in the audit_context
1941  * @serial: serial value that is recorded in the audit_context
1942  *
1943  * Also sets the context as auditable.
1944  */
1945 void auditsc_get_stamp(struct audit_context *ctx,
1946 		       struct timespec *t, unsigned int *serial)
1947 {
1948 	if (!ctx->serial)
1949 		ctx->serial = audit_serial();
1950 	t->tv_sec  = ctx->ctime.tv_sec;
1951 	t->tv_nsec = ctx->ctime.tv_nsec;
1952 	*serial    = ctx->serial;
1953 	ctx->auditable = 1;
1954 }
1955 
1956 /* global counter which is incremented every time something logs in */
1957 static atomic_t session_id = ATOMIC_INIT(0);
1958 
1959 /**
1960  * audit_set_loginuid - set a task's audit_context loginuid
1961  * @task: task whose audit context is being modified
1962  * @loginuid: loginuid value
1963  *
1964  * Returns 0.
1965  *
1966  * Called (set) from fs/proc/base.c::proc_loginuid_write().
1967  */
1968 int audit_set_loginuid(struct task_struct *task, uid_t loginuid)
1969 {
1970 	unsigned int sessionid = atomic_inc_return(&session_id);
1971 	struct audit_context *context = task->audit_context;
1972 
1973 	if (context && context->in_syscall) {
1974 		struct audit_buffer *ab;
1975 
1976 		ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
1977 		if (ab) {
1978 			audit_log_format(ab, "login pid=%d uid=%u "
1979 				"old auid=%u new auid=%u"
1980 				" old ses=%u new ses=%u",
1981 				task->pid, task->uid,
1982 				task->loginuid, loginuid,
1983 				task->sessionid, sessionid);
1984 			audit_log_end(ab);
1985 		}
1986 	}
1987 	task->sessionid = sessionid;
1988 	task->loginuid = loginuid;
1989 	return 0;
1990 }
1991 
1992 /**
1993  * __audit_mq_open - record audit data for a POSIX MQ open
1994  * @oflag: open flag
1995  * @mode: mode bits
1996  * @u_attr: queue attributes
1997  *
1998  * Returns 0 for success or NULL context or < 0 on error.
1999  */
2000 int __audit_mq_open(int oflag, mode_t mode, struct mq_attr __user *u_attr)
2001 {
2002 	struct audit_aux_data_mq_open *ax;
2003 	struct audit_context *context = current->audit_context;
2004 
2005 	if (!audit_enabled)
2006 		return 0;
2007 
2008 	if (likely(!context))
2009 		return 0;
2010 
2011 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2012 	if (!ax)
2013 		return -ENOMEM;
2014 
2015 	if (u_attr != NULL) {
2016 		if (copy_from_user(&ax->attr, u_attr, sizeof(ax->attr))) {
2017 			kfree(ax);
2018 			return -EFAULT;
2019 		}
2020 	} else
2021 		memset(&ax->attr, 0, sizeof(ax->attr));
2022 
2023 	ax->oflag = oflag;
2024 	ax->mode = mode;
2025 
2026 	ax->d.type = AUDIT_MQ_OPEN;
2027 	ax->d.next = context->aux;
2028 	context->aux = (void *)ax;
2029 	return 0;
2030 }
2031 
2032 /**
2033  * __audit_mq_timedsend - record audit data for a POSIX MQ timed send
2034  * @mqdes: MQ descriptor
2035  * @msg_len: Message length
2036  * @msg_prio: Message priority
2037  * @u_abs_timeout: Message timeout in absolute time
2038  *
2039  * Returns 0 for success or NULL context or < 0 on error.
2040  */
2041 int __audit_mq_timedsend(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2042 			const struct timespec __user *u_abs_timeout)
2043 {
2044 	struct audit_aux_data_mq_sendrecv *ax;
2045 	struct audit_context *context = current->audit_context;
2046 
2047 	if (!audit_enabled)
2048 		return 0;
2049 
2050 	if (likely(!context))
2051 		return 0;
2052 
2053 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2054 	if (!ax)
2055 		return -ENOMEM;
2056 
2057 	if (u_abs_timeout != NULL) {
2058 		if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) {
2059 			kfree(ax);
2060 			return -EFAULT;
2061 		}
2062 	} else
2063 		memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout));
2064 
2065 	ax->mqdes = mqdes;
2066 	ax->msg_len = msg_len;
2067 	ax->msg_prio = msg_prio;
2068 
2069 	ax->d.type = AUDIT_MQ_SENDRECV;
2070 	ax->d.next = context->aux;
2071 	context->aux = (void *)ax;
2072 	return 0;
2073 }
2074 
2075 /**
2076  * __audit_mq_timedreceive - record audit data for a POSIX MQ timed receive
2077  * @mqdes: MQ descriptor
2078  * @msg_len: Message length
2079  * @u_msg_prio: Message priority
2080  * @u_abs_timeout: Message timeout in absolute time
2081  *
2082  * Returns 0 for success or NULL context or < 0 on error.
2083  */
2084 int __audit_mq_timedreceive(mqd_t mqdes, size_t msg_len,
2085 				unsigned int __user *u_msg_prio,
2086 				const struct timespec __user *u_abs_timeout)
2087 {
2088 	struct audit_aux_data_mq_sendrecv *ax;
2089 	struct audit_context *context = current->audit_context;
2090 
2091 	if (!audit_enabled)
2092 		return 0;
2093 
2094 	if (likely(!context))
2095 		return 0;
2096 
2097 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2098 	if (!ax)
2099 		return -ENOMEM;
2100 
2101 	if (u_msg_prio != NULL) {
2102 		if (get_user(ax->msg_prio, u_msg_prio)) {
2103 			kfree(ax);
2104 			return -EFAULT;
2105 		}
2106 	} else
2107 		ax->msg_prio = 0;
2108 
2109 	if (u_abs_timeout != NULL) {
2110 		if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) {
2111 			kfree(ax);
2112 			return -EFAULT;
2113 		}
2114 	} else
2115 		memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout));
2116 
2117 	ax->mqdes = mqdes;
2118 	ax->msg_len = msg_len;
2119 
2120 	ax->d.type = AUDIT_MQ_SENDRECV;
2121 	ax->d.next = context->aux;
2122 	context->aux = (void *)ax;
2123 	return 0;
2124 }
2125 
2126 /**
2127  * __audit_mq_notify - record audit data for a POSIX MQ notify
2128  * @mqdes: MQ descriptor
2129  * @u_notification: Notification event
2130  *
2131  * Returns 0 for success or NULL context or < 0 on error.
2132  */
2133 
2134 int __audit_mq_notify(mqd_t mqdes, const struct sigevent __user *u_notification)
2135 {
2136 	struct audit_aux_data_mq_notify *ax;
2137 	struct audit_context *context = current->audit_context;
2138 
2139 	if (!audit_enabled)
2140 		return 0;
2141 
2142 	if (likely(!context))
2143 		return 0;
2144 
2145 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2146 	if (!ax)
2147 		return -ENOMEM;
2148 
2149 	if (u_notification != NULL) {
2150 		if (copy_from_user(&ax->notification, u_notification, sizeof(ax->notification))) {
2151 			kfree(ax);
2152 			return -EFAULT;
2153 		}
2154 	} else
2155 		memset(&ax->notification, 0, sizeof(ax->notification));
2156 
2157 	ax->mqdes = mqdes;
2158 
2159 	ax->d.type = AUDIT_MQ_NOTIFY;
2160 	ax->d.next = context->aux;
2161 	context->aux = (void *)ax;
2162 	return 0;
2163 }
2164 
2165 /**
2166  * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2167  * @mqdes: MQ descriptor
2168  * @mqstat: MQ flags
2169  *
2170  * Returns 0 for success or NULL context or < 0 on error.
2171  */
2172 int __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2173 {
2174 	struct audit_aux_data_mq_getsetattr *ax;
2175 	struct audit_context *context = current->audit_context;
2176 
2177 	if (!audit_enabled)
2178 		return 0;
2179 
2180 	if (likely(!context))
2181 		return 0;
2182 
2183 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2184 	if (!ax)
2185 		return -ENOMEM;
2186 
2187 	ax->mqdes = mqdes;
2188 	ax->mqstat = *mqstat;
2189 
2190 	ax->d.type = AUDIT_MQ_GETSETATTR;
2191 	ax->d.next = context->aux;
2192 	context->aux = (void *)ax;
2193 	return 0;
2194 }
2195 
2196 /**
2197  * audit_ipc_obj - record audit data for ipc object
2198  * @ipcp: ipc permissions
2199  *
2200  * Returns 0 for success or NULL context or < 0 on error.
2201  */
2202 int __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2203 {
2204 	struct audit_aux_data_ipcctl *ax;
2205 	struct audit_context *context = current->audit_context;
2206 
2207 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2208 	if (!ax)
2209 		return -ENOMEM;
2210 
2211 	ax->uid = ipcp->uid;
2212 	ax->gid = ipcp->gid;
2213 	ax->mode = ipcp->mode;
2214 	security_ipc_getsecid(ipcp, &ax->osid);
2215 	ax->d.type = AUDIT_IPC;
2216 	ax->d.next = context->aux;
2217 	context->aux = (void *)ax;
2218 	return 0;
2219 }
2220 
2221 /**
2222  * audit_ipc_set_perm - record audit data for new ipc permissions
2223  * @qbytes: msgq bytes
2224  * @uid: msgq user id
2225  * @gid: msgq group id
2226  * @mode: msgq mode (permissions)
2227  *
2228  * Returns 0 for success or NULL context or < 0 on error.
2229  */
2230 int __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode)
2231 {
2232 	struct audit_aux_data_ipcctl *ax;
2233 	struct audit_context *context = current->audit_context;
2234 
2235 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
2236 	if (!ax)
2237 		return -ENOMEM;
2238 
2239 	ax->qbytes = qbytes;
2240 	ax->uid = uid;
2241 	ax->gid = gid;
2242 	ax->mode = mode;
2243 
2244 	ax->d.type = AUDIT_IPC_SET_PERM;
2245 	ax->d.next = context->aux;
2246 	context->aux = (void *)ax;
2247 	return 0;
2248 }
2249 
2250 int audit_bprm(struct linux_binprm *bprm)
2251 {
2252 	struct audit_aux_data_execve *ax;
2253 	struct audit_context *context = current->audit_context;
2254 
2255 	if (likely(!audit_enabled || !context || context->dummy))
2256 		return 0;
2257 
2258 	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2259 	if (!ax)
2260 		return -ENOMEM;
2261 
2262 	ax->argc = bprm->argc;
2263 	ax->envc = bprm->envc;
2264 	ax->mm = bprm->mm;
2265 	ax->d.type = AUDIT_EXECVE;
2266 	ax->d.next = context->aux;
2267 	context->aux = (void *)ax;
2268 	return 0;
2269 }
2270 
2271 
2272 /**
2273  * audit_socketcall - record audit data for sys_socketcall
2274  * @nargs: number of args
2275  * @args: args array
2276  *
2277  * Returns 0 for success or NULL context or < 0 on error.
2278  */
2279 int audit_socketcall(int nargs, unsigned long *args)
2280 {
2281 	struct audit_aux_data_socketcall *ax;
2282 	struct audit_context *context = current->audit_context;
2283 
2284 	if (likely(!context || context->dummy))
2285 		return 0;
2286 
2287 	ax = kmalloc(sizeof(*ax) + nargs * sizeof(unsigned long), GFP_KERNEL);
2288 	if (!ax)
2289 		return -ENOMEM;
2290 
2291 	ax->nargs = nargs;
2292 	memcpy(ax->args, args, nargs * sizeof(unsigned long));
2293 
2294 	ax->d.type = AUDIT_SOCKETCALL;
2295 	ax->d.next = context->aux;
2296 	context->aux = (void *)ax;
2297 	return 0;
2298 }
2299 
2300 /**
2301  * __audit_fd_pair - record audit data for pipe and socketpair
2302  * @fd1: the first file descriptor
2303  * @fd2: the second file descriptor
2304  *
2305  * Returns 0 for success or NULL context or < 0 on error.
2306  */
2307 int __audit_fd_pair(int fd1, int fd2)
2308 {
2309 	struct audit_context *context = current->audit_context;
2310 	struct audit_aux_data_fd_pair *ax;
2311 
2312 	if (likely(!context)) {
2313 		return 0;
2314 	}
2315 
2316 	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2317 	if (!ax) {
2318 		return -ENOMEM;
2319 	}
2320 
2321 	ax->fd[0] = fd1;
2322 	ax->fd[1] = fd2;
2323 
2324 	ax->d.type = AUDIT_FD_PAIR;
2325 	ax->d.next = context->aux;
2326 	context->aux = (void *)ax;
2327 	return 0;
2328 }
2329 
2330 /**
2331  * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2332  * @len: data length in user space
2333  * @a: data address in kernel space
2334  *
2335  * Returns 0 for success or NULL context or < 0 on error.
2336  */
2337 int audit_sockaddr(int len, void *a)
2338 {
2339 	struct audit_aux_data_sockaddr *ax;
2340 	struct audit_context *context = current->audit_context;
2341 
2342 	if (likely(!context || context->dummy))
2343 		return 0;
2344 
2345 	ax = kmalloc(sizeof(*ax) + len, GFP_KERNEL);
2346 	if (!ax)
2347 		return -ENOMEM;
2348 
2349 	ax->len = len;
2350 	memcpy(ax->a, a, len);
2351 
2352 	ax->d.type = AUDIT_SOCKADDR;
2353 	ax->d.next = context->aux;
2354 	context->aux = (void *)ax;
2355 	return 0;
2356 }
2357 
2358 void __audit_ptrace(struct task_struct *t)
2359 {
2360 	struct audit_context *context = current->audit_context;
2361 
2362 	context->target_pid = t->pid;
2363 	context->target_auid = audit_get_loginuid(t);
2364 	context->target_uid = t->uid;
2365 	context->target_sessionid = audit_get_sessionid(t);
2366 	security_task_getsecid(t, &context->target_sid);
2367 	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
2368 }
2369 
2370 /**
2371  * audit_signal_info - record signal info for shutting down audit subsystem
2372  * @sig: signal value
2373  * @t: task being signaled
2374  *
2375  * If the audit subsystem is being terminated, record the task (pid)
2376  * and uid that is doing that.
2377  */
2378 int __audit_signal_info(int sig, struct task_struct *t)
2379 {
2380 	struct audit_aux_data_pids *axp;
2381 	struct task_struct *tsk = current;
2382 	struct audit_context *ctx = tsk->audit_context;
2383 
2384 	if (audit_pid && t->tgid == audit_pid) {
2385 		if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
2386 			audit_sig_pid = tsk->pid;
2387 			if (tsk->loginuid != -1)
2388 				audit_sig_uid = tsk->loginuid;
2389 			else
2390 				audit_sig_uid = tsk->uid;
2391 			security_task_getsecid(tsk, &audit_sig_sid);
2392 		}
2393 		if (!audit_signals || audit_dummy_context())
2394 			return 0;
2395 	}
2396 
2397 	/* optimize the common case by putting first signal recipient directly
2398 	 * in audit_context */
2399 	if (!ctx->target_pid) {
2400 		ctx->target_pid = t->tgid;
2401 		ctx->target_auid = audit_get_loginuid(t);
2402 		ctx->target_uid = t->uid;
2403 		ctx->target_sessionid = audit_get_sessionid(t);
2404 		security_task_getsecid(t, &ctx->target_sid);
2405 		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
2406 		return 0;
2407 	}
2408 
2409 	axp = (void *)ctx->aux_pids;
2410 	if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2411 		axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2412 		if (!axp)
2413 			return -ENOMEM;
2414 
2415 		axp->d.type = AUDIT_OBJ_PID;
2416 		axp->d.next = ctx->aux_pids;
2417 		ctx->aux_pids = (void *)axp;
2418 	}
2419 	BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2420 
2421 	axp->target_pid[axp->pid_count] = t->tgid;
2422 	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2423 	axp->target_uid[axp->pid_count] = t->uid;
2424 	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2425 	security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2426 	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
2427 	axp->pid_count++;
2428 
2429 	return 0;
2430 }
2431 
2432 /**
2433  * audit_core_dumps - record information about processes that end abnormally
2434  * @signr: signal value
2435  *
2436  * If a process ends with a core dump, something fishy is going on and we
2437  * should record the event for investigation.
2438  */
2439 void audit_core_dumps(long signr)
2440 {
2441 	struct audit_buffer *ab;
2442 	u32 sid;
2443 	uid_t auid = audit_get_loginuid(current);
2444 	unsigned int sessionid = audit_get_sessionid(current);
2445 
2446 	if (!audit_enabled)
2447 		return;
2448 
2449 	if (signr == SIGQUIT)	/* don't care for those */
2450 		return;
2451 
2452 	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2453 	audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2454 			auid, current->uid, current->gid, sessionid);
2455 	security_task_getsecid(current, &sid);
2456 	if (sid) {
2457 		char *ctx = NULL;
2458 		u32 len;
2459 
2460 		if (security_secid_to_secctx(sid, &ctx, &len))
2461 			audit_log_format(ab, " ssid=%u", sid);
2462 		else {
2463 			audit_log_format(ab, " subj=%s", ctx);
2464 			security_release_secctx(ctx, len);
2465 		}
2466 	}
2467 	audit_log_format(ab, " pid=%d comm=", current->pid);
2468 	audit_log_untrustedstring(ab, current->comm);
2469 	audit_log_format(ab, " sig=%ld", signr);
2470 	audit_log_end(ab);
2471 }
2472