xref: /linux/kernel/auditsc.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
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/slab.h>
53 #include <linux/mount.h>
54 #include <linux/socket.h>
55 #include <linux/mqueue.h>
56 #include <linux/audit.h>
57 #include <linux/personality.h>
58 #include <linux/time.h>
59 #include <linux/netlink.h>
60 #include <linux/compiler.h>
61 #include <asm/unistd.h>
62 #include <linux/security.h>
63 #include <linux/list.h>
64 #include <linux/tty.h>
65 #include <linux/binfmts.h>
66 #include <linux/highmem.h>
67 #include <linux/syscalls.h>
68 #include <linux/capability.h>
69 #include <linux/fs_struct.h>
70 
71 #include "audit.h"
72 
73 /* AUDIT_NAMES is the number of slots we reserve in the audit_context
74  * for saving names from getname(). */
75 #define AUDIT_NAMES    20
76 
77 /* Indicates that audit should log the full pathname. */
78 #define AUDIT_NAME_FULL -1
79 
80 /* no execve audit message should be longer than this (userspace limits) */
81 #define MAX_EXECVE_AUDIT_LEN 7500
82 
83 /* number of audit rules */
84 int audit_n_rules;
85 
86 /* determines whether we collect data for signals sent */
87 int audit_signals;
88 
89 struct audit_cap_data {
90 	kernel_cap_t		permitted;
91 	kernel_cap_t		inheritable;
92 	union {
93 		unsigned int	fE;		/* effective bit of a file capability */
94 		kernel_cap_t	effective;	/* effective set of a process */
95 	};
96 };
97 
98 /* When fs/namei.c:getname() is called, we store the pointer in name and
99  * we don't let putname() free it (instead we free all of the saved
100  * pointers at syscall exit time).
101  *
102  * Further, in fs/namei.c:path_lookup() we store the inode and device. */
103 struct audit_names {
104 	const char	*name;
105 	int		name_len;	/* number of name's characters to log */
106 	unsigned	name_put;	/* call __putname() for this name */
107 	unsigned long	ino;
108 	dev_t		dev;
109 	umode_t		mode;
110 	uid_t		uid;
111 	gid_t		gid;
112 	dev_t		rdev;
113 	u32		osid;
114 	struct audit_cap_data fcap;
115 	unsigned int	fcap_ver;
116 };
117 
118 struct audit_aux_data {
119 	struct audit_aux_data	*next;
120 	int			type;
121 };
122 
123 #define AUDIT_AUX_IPCPERM	0
124 
125 /* Number of target pids per aux struct. */
126 #define AUDIT_AUX_PIDS	16
127 
128 struct audit_aux_data_execve {
129 	struct audit_aux_data	d;
130 	int argc;
131 	int envc;
132 	struct mm_struct *mm;
133 };
134 
135 struct audit_aux_data_pids {
136 	struct audit_aux_data	d;
137 	pid_t			target_pid[AUDIT_AUX_PIDS];
138 	uid_t			target_auid[AUDIT_AUX_PIDS];
139 	uid_t			target_uid[AUDIT_AUX_PIDS];
140 	unsigned int		target_sessionid[AUDIT_AUX_PIDS];
141 	u32			target_sid[AUDIT_AUX_PIDS];
142 	char 			target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
143 	int			pid_count;
144 };
145 
146 struct audit_aux_data_bprm_fcaps {
147 	struct audit_aux_data	d;
148 	struct audit_cap_data	fcap;
149 	unsigned int		fcap_ver;
150 	struct audit_cap_data	old_pcap;
151 	struct audit_cap_data	new_pcap;
152 };
153 
154 struct audit_aux_data_capset {
155 	struct audit_aux_data	d;
156 	pid_t			pid;
157 	struct audit_cap_data	cap;
158 };
159 
160 struct audit_tree_refs {
161 	struct audit_tree_refs *next;
162 	struct audit_chunk *c[31];
163 };
164 
165 /* The per-task audit context. */
166 struct audit_context {
167 	int		    dummy;	/* must be the first element */
168 	int		    in_syscall;	/* 1 if task is in a syscall */
169 	enum audit_state    state, current_state;
170 	unsigned int	    serial;     /* serial number for record */
171 	int		    major;      /* syscall number */
172 	struct timespec	    ctime;      /* time of syscall entry */
173 	unsigned long	    argv[4];    /* syscall arguments */
174 	long		    return_code;/* syscall return code */
175 	u64		    prio;
176 	int		    return_valid; /* return code is valid */
177 	int		    name_count;
178 	struct audit_names  names[AUDIT_NAMES];
179 	char *		    filterkey;	/* key for rule that triggered record */
180 	struct path	    pwd;
181 	struct audit_context *previous; /* For nested syscalls */
182 	struct audit_aux_data *aux;
183 	struct audit_aux_data *aux_pids;
184 	struct sockaddr_storage *sockaddr;
185 	size_t sockaddr_len;
186 				/* Save things to print about task_struct */
187 	pid_t		    pid, ppid;
188 	uid_t		    uid, euid, suid, fsuid;
189 	gid_t		    gid, egid, sgid, fsgid;
190 	unsigned long	    personality;
191 	int		    arch;
192 
193 	pid_t		    target_pid;
194 	uid_t		    target_auid;
195 	uid_t		    target_uid;
196 	unsigned int	    target_sessionid;
197 	u32		    target_sid;
198 	char		    target_comm[TASK_COMM_LEN];
199 
200 	struct audit_tree_refs *trees, *first_trees;
201 	struct list_head killed_trees;
202 	int tree_count;
203 
204 	int type;
205 	union {
206 		struct {
207 			int nargs;
208 			long args[6];
209 		} socketcall;
210 		struct {
211 			uid_t			uid;
212 			gid_t			gid;
213 			mode_t			mode;
214 			u32			osid;
215 			int			has_perm;
216 			uid_t			perm_uid;
217 			gid_t			perm_gid;
218 			mode_t			perm_mode;
219 			unsigned long		qbytes;
220 		} ipc;
221 		struct {
222 			mqd_t			mqdes;
223 			struct mq_attr 		mqstat;
224 		} mq_getsetattr;
225 		struct {
226 			mqd_t			mqdes;
227 			int			sigev_signo;
228 		} mq_notify;
229 		struct {
230 			mqd_t			mqdes;
231 			size_t			msg_len;
232 			unsigned int		msg_prio;
233 			struct timespec		abs_timeout;
234 		} mq_sendrecv;
235 		struct {
236 			int			oflag;
237 			mode_t			mode;
238 			struct mq_attr		attr;
239 		} mq_open;
240 		struct {
241 			pid_t			pid;
242 			struct audit_cap_data	cap;
243 		} capset;
244 	};
245 	int fds[2];
246 
247 #if AUDIT_DEBUG
248 	int		    put_count;
249 	int		    ino_count;
250 #endif
251 };
252 
253 static inline int open_arg(int flags, int mask)
254 {
255 	int n = ACC_MODE(flags);
256 	if (flags & (O_TRUNC | O_CREAT))
257 		n |= AUDIT_PERM_WRITE;
258 	return n & mask;
259 }
260 
261 static int audit_match_perm(struct audit_context *ctx, int mask)
262 {
263 	unsigned n;
264 	if (unlikely(!ctx))
265 		return 0;
266 	n = ctx->major;
267 
268 	switch (audit_classify_syscall(ctx->arch, n)) {
269 	case 0:	/* native */
270 		if ((mask & AUDIT_PERM_WRITE) &&
271 		     audit_match_class(AUDIT_CLASS_WRITE, n))
272 			return 1;
273 		if ((mask & AUDIT_PERM_READ) &&
274 		     audit_match_class(AUDIT_CLASS_READ, n))
275 			return 1;
276 		if ((mask & AUDIT_PERM_ATTR) &&
277 		     audit_match_class(AUDIT_CLASS_CHATTR, n))
278 			return 1;
279 		return 0;
280 	case 1: /* 32bit on biarch */
281 		if ((mask & AUDIT_PERM_WRITE) &&
282 		     audit_match_class(AUDIT_CLASS_WRITE_32, n))
283 			return 1;
284 		if ((mask & AUDIT_PERM_READ) &&
285 		     audit_match_class(AUDIT_CLASS_READ_32, n))
286 			return 1;
287 		if ((mask & AUDIT_PERM_ATTR) &&
288 		     audit_match_class(AUDIT_CLASS_CHATTR_32, n))
289 			return 1;
290 		return 0;
291 	case 2: /* open */
292 		return mask & ACC_MODE(ctx->argv[1]);
293 	case 3: /* openat */
294 		return mask & ACC_MODE(ctx->argv[2]);
295 	case 4: /* socketcall */
296 		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
297 	case 5: /* execve */
298 		return mask & AUDIT_PERM_EXEC;
299 	default:
300 		return 0;
301 	}
302 }
303 
304 static int audit_match_filetype(struct audit_context *ctx, int which)
305 {
306 	unsigned index = which & ~S_IFMT;
307 	mode_t mode = which & S_IFMT;
308 
309 	if (unlikely(!ctx))
310 		return 0;
311 
312 	if (index >= ctx->name_count)
313 		return 0;
314 	if (ctx->names[index].ino == -1)
315 		return 0;
316 	if ((ctx->names[index].mode ^ mode) & S_IFMT)
317 		return 0;
318 	return 1;
319 }
320 
321 /*
322  * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
323  * ->first_trees points to its beginning, ->trees - to the current end of data.
324  * ->tree_count is the number of free entries in array pointed to by ->trees.
325  * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
326  * "empty" becomes (p, p, 31) afterwards.  We don't shrink the list (and seriously,
327  * it's going to remain 1-element for almost any setup) until we free context itself.
328  * References in it _are_ dropped - at the same time we free/drop aux stuff.
329  */
330 
331 #ifdef CONFIG_AUDIT_TREE
332 static void audit_set_auditable(struct audit_context *ctx)
333 {
334 	if (!ctx->prio) {
335 		ctx->prio = 1;
336 		ctx->current_state = AUDIT_RECORD_CONTEXT;
337 	}
338 }
339 
340 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
341 {
342 	struct audit_tree_refs *p = ctx->trees;
343 	int left = ctx->tree_count;
344 	if (likely(left)) {
345 		p->c[--left] = chunk;
346 		ctx->tree_count = left;
347 		return 1;
348 	}
349 	if (!p)
350 		return 0;
351 	p = p->next;
352 	if (p) {
353 		p->c[30] = chunk;
354 		ctx->trees = p;
355 		ctx->tree_count = 30;
356 		return 1;
357 	}
358 	return 0;
359 }
360 
361 static int grow_tree_refs(struct audit_context *ctx)
362 {
363 	struct audit_tree_refs *p = ctx->trees;
364 	ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
365 	if (!ctx->trees) {
366 		ctx->trees = p;
367 		return 0;
368 	}
369 	if (p)
370 		p->next = ctx->trees;
371 	else
372 		ctx->first_trees = ctx->trees;
373 	ctx->tree_count = 31;
374 	return 1;
375 }
376 #endif
377 
378 static void unroll_tree_refs(struct audit_context *ctx,
379 		      struct audit_tree_refs *p, int count)
380 {
381 #ifdef CONFIG_AUDIT_TREE
382 	struct audit_tree_refs *q;
383 	int n;
384 	if (!p) {
385 		/* we started with empty chain */
386 		p = ctx->first_trees;
387 		count = 31;
388 		/* if the very first allocation has failed, nothing to do */
389 		if (!p)
390 			return;
391 	}
392 	n = count;
393 	for (q = p; q != ctx->trees; q = q->next, n = 31) {
394 		while (n--) {
395 			audit_put_chunk(q->c[n]);
396 			q->c[n] = NULL;
397 		}
398 	}
399 	while (n-- > ctx->tree_count) {
400 		audit_put_chunk(q->c[n]);
401 		q->c[n] = NULL;
402 	}
403 	ctx->trees = p;
404 	ctx->tree_count = count;
405 #endif
406 }
407 
408 static void free_tree_refs(struct audit_context *ctx)
409 {
410 	struct audit_tree_refs *p, *q;
411 	for (p = ctx->first_trees; p; p = q) {
412 		q = p->next;
413 		kfree(p);
414 	}
415 }
416 
417 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
418 {
419 #ifdef CONFIG_AUDIT_TREE
420 	struct audit_tree_refs *p;
421 	int n;
422 	if (!tree)
423 		return 0;
424 	/* full ones */
425 	for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
426 		for (n = 0; n < 31; n++)
427 			if (audit_tree_match(p->c[n], tree))
428 				return 1;
429 	}
430 	/* partial */
431 	if (p) {
432 		for (n = ctx->tree_count; n < 31; n++)
433 			if (audit_tree_match(p->c[n], tree))
434 				return 1;
435 	}
436 #endif
437 	return 0;
438 }
439 
440 /* Determine if any context name data matches a rule's watch data */
441 /* Compare a task_struct with an audit_rule.  Return 1 on match, 0
442  * otherwise. */
443 static int audit_filter_rules(struct task_struct *tsk,
444 			      struct audit_krule *rule,
445 			      struct audit_context *ctx,
446 			      struct audit_names *name,
447 			      enum audit_state *state)
448 {
449 	const struct cred *cred = get_task_cred(tsk);
450 	int i, j, need_sid = 1;
451 	u32 sid;
452 
453 	for (i = 0; i < rule->field_count; i++) {
454 		struct audit_field *f = &rule->fields[i];
455 		int result = 0;
456 
457 		switch (f->type) {
458 		case AUDIT_PID:
459 			result = audit_comparator(tsk->pid, f->op, f->val);
460 			break;
461 		case AUDIT_PPID:
462 			if (ctx) {
463 				if (!ctx->ppid)
464 					ctx->ppid = sys_getppid();
465 				result = audit_comparator(ctx->ppid, f->op, f->val);
466 			}
467 			break;
468 		case AUDIT_UID:
469 			result = audit_comparator(cred->uid, f->op, f->val);
470 			break;
471 		case AUDIT_EUID:
472 			result = audit_comparator(cred->euid, f->op, f->val);
473 			break;
474 		case AUDIT_SUID:
475 			result = audit_comparator(cred->suid, f->op, f->val);
476 			break;
477 		case AUDIT_FSUID:
478 			result = audit_comparator(cred->fsuid, f->op, f->val);
479 			break;
480 		case AUDIT_GID:
481 			result = audit_comparator(cred->gid, f->op, f->val);
482 			break;
483 		case AUDIT_EGID:
484 			result = audit_comparator(cred->egid, f->op, f->val);
485 			break;
486 		case AUDIT_SGID:
487 			result = audit_comparator(cred->sgid, f->op, f->val);
488 			break;
489 		case AUDIT_FSGID:
490 			result = audit_comparator(cred->fsgid, f->op, f->val);
491 			break;
492 		case AUDIT_PERS:
493 			result = audit_comparator(tsk->personality, f->op, f->val);
494 			break;
495 		case AUDIT_ARCH:
496 			if (ctx)
497 				result = audit_comparator(ctx->arch, f->op, f->val);
498 			break;
499 
500 		case AUDIT_EXIT:
501 			if (ctx && ctx->return_valid)
502 				result = audit_comparator(ctx->return_code, f->op, f->val);
503 			break;
504 		case AUDIT_SUCCESS:
505 			if (ctx && ctx->return_valid) {
506 				if (f->val)
507 					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
508 				else
509 					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
510 			}
511 			break;
512 		case AUDIT_DEVMAJOR:
513 			if (name)
514 				result = audit_comparator(MAJOR(name->dev),
515 							  f->op, f->val);
516 			else if (ctx) {
517 				for (j = 0; j < ctx->name_count; j++) {
518 					if (audit_comparator(MAJOR(ctx->names[j].dev),	f->op, f->val)) {
519 						++result;
520 						break;
521 					}
522 				}
523 			}
524 			break;
525 		case AUDIT_DEVMINOR:
526 			if (name)
527 				result = audit_comparator(MINOR(name->dev),
528 							  f->op, f->val);
529 			else if (ctx) {
530 				for (j = 0; j < ctx->name_count; j++) {
531 					if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) {
532 						++result;
533 						break;
534 					}
535 				}
536 			}
537 			break;
538 		case AUDIT_INODE:
539 			if (name)
540 				result = (name->ino == f->val);
541 			else if (ctx) {
542 				for (j = 0; j < ctx->name_count; j++) {
543 					if (audit_comparator(ctx->names[j].ino, f->op, f->val)) {
544 						++result;
545 						break;
546 					}
547 				}
548 			}
549 			break;
550 		case AUDIT_WATCH:
551 			if (name)
552 				result = audit_watch_compare(rule->watch, name->ino, name->dev);
553 			break;
554 		case AUDIT_DIR:
555 			if (ctx)
556 				result = match_tree_refs(ctx, rule->tree);
557 			break;
558 		case AUDIT_LOGINUID:
559 			result = 0;
560 			if (ctx)
561 				result = audit_comparator(tsk->loginuid, f->op, f->val);
562 			break;
563 		case AUDIT_SUBJ_USER:
564 		case AUDIT_SUBJ_ROLE:
565 		case AUDIT_SUBJ_TYPE:
566 		case AUDIT_SUBJ_SEN:
567 		case AUDIT_SUBJ_CLR:
568 			/* NOTE: this may return negative values indicating
569 			   a temporary error.  We simply treat this as a
570 			   match for now to avoid losing information that
571 			   may be wanted.   An error message will also be
572 			   logged upon error */
573 			if (f->lsm_rule) {
574 				if (need_sid) {
575 					security_task_getsecid(tsk, &sid);
576 					need_sid = 0;
577 				}
578 				result = security_audit_rule_match(sid, f->type,
579 				                                  f->op,
580 				                                  f->lsm_rule,
581 				                                  ctx);
582 			}
583 			break;
584 		case AUDIT_OBJ_USER:
585 		case AUDIT_OBJ_ROLE:
586 		case AUDIT_OBJ_TYPE:
587 		case AUDIT_OBJ_LEV_LOW:
588 		case AUDIT_OBJ_LEV_HIGH:
589 			/* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
590 			   also applies here */
591 			if (f->lsm_rule) {
592 				/* Find files that match */
593 				if (name) {
594 					result = security_audit_rule_match(
595 					           name->osid, f->type, f->op,
596 					           f->lsm_rule, ctx);
597 				} else if (ctx) {
598 					for (j = 0; j < ctx->name_count; j++) {
599 						if (security_audit_rule_match(
600 						      ctx->names[j].osid,
601 						      f->type, f->op,
602 						      f->lsm_rule, ctx)) {
603 							++result;
604 							break;
605 						}
606 					}
607 				}
608 				/* Find ipc objects that match */
609 				if (!ctx || ctx->type != AUDIT_IPC)
610 					break;
611 				if (security_audit_rule_match(ctx->ipc.osid,
612 							      f->type, f->op,
613 							      f->lsm_rule, ctx))
614 					++result;
615 			}
616 			break;
617 		case AUDIT_ARG0:
618 		case AUDIT_ARG1:
619 		case AUDIT_ARG2:
620 		case AUDIT_ARG3:
621 			if (ctx)
622 				result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
623 			break;
624 		case AUDIT_FILTERKEY:
625 			/* ignore this field for filtering */
626 			result = 1;
627 			break;
628 		case AUDIT_PERM:
629 			result = audit_match_perm(ctx, f->val);
630 			break;
631 		case AUDIT_FILETYPE:
632 			result = audit_match_filetype(ctx, f->val);
633 			break;
634 		}
635 
636 		if (!result) {
637 			put_cred(cred);
638 			return 0;
639 		}
640 	}
641 
642 	if (ctx) {
643 		if (rule->prio <= ctx->prio)
644 			return 0;
645 		if (rule->filterkey) {
646 			kfree(ctx->filterkey);
647 			ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
648 		}
649 		ctx->prio = rule->prio;
650 	}
651 	switch (rule->action) {
652 	case AUDIT_NEVER:    *state = AUDIT_DISABLED;	    break;
653 	case AUDIT_ALWAYS:   *state = AUDIT_RECORD_CONTEXT; break;
654 	}
655 	put_cred(cred);
656 	return 1;
657 }
658 
659 /* At process creation time, we can determine if system-call auditing is
660  * completely disabled for this task.  Since we only have the task
661  * structure at this point, we can only check uid and gid.
662  */
663 static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
664 {
665 	struct audit_entry *e;
666 	enum audit_state   state;
667 
668 	rcu_read_lock();
669 	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
670 		if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) {
671 			if (state == AUDIT_RECORD_CONTEXT)
672 				*key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
673 			rcu_read_unlock();
674 			return state;
675 		}
676 	}
677 	rcu_read_unlock();
678 	return AUDIT_BUILD_CONTEXT;
679 }
680 
681 /* At syscall entry and exit time, this filter is called if the
682  * audit_state is not low enough that auditing cannot take place, but is
683  * also not high enough that we already know we have to write an audit
684  * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
685  */
686 static enum audit_state audit_filter_syscall(struct task_struct *tsk,
687 					     struct audit_context *ctx,
688 					     struct list_head *list)
689 {
690 	struct audit_entry *e;
691 	enum audit_state state;
692 
693 	if (audit_pid && tsk->tgid == audit_pid)
694 		return AUDIT_DISABLED;
695 
696 	rcu_read_lock();
697 	if (!list_empty(list)) {
698 		int word = AUDIT_WORD(ctx->major);
699 		int bit  = AUDIT_BIT(ctx->major);
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, NULL,
704 					       &state)) {
705 				rcu_read_unlock();
706 				ctx->current_state = state;
707 				return state;
708 			}
709 		}
710 	}
711 	rcu_read_unlock();
712 	return AUDIT_BUILD_CONTEXT;
713 }
714 
715 /* At syscall exit time, this filter is called if any audit_names[] have been
716  * collected during syscall processing.  We only check rules in sublists at hash
717  * buckets applicable to the inode numbers in audit_names[].
718  * Regarding audit_state, same rules apply as for audit_filter_syscall().
719  */
720 void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
721 {
722 	int i;
723 	struct audit_entry *e;
724 	enum audit_state state;
725 
726 	if (audit_pid && tsk->tgid == audit_pid)
727 		return;
728 
729 	rcu_read_lock();
730 	for (i = 0; i < ctx->name_count; i++) {
731 		int word = AUDIT_WORD(ctx->major);
732 		int bit  = AUDIT_BIT(ctx->major);
733 		struct audit_names *n = &ctx->names[i];
734 		int h = audit_hash_ino((u32)n->ino);
735 		struct list_head *list = &audit_inode_hash[h];
736 
737 		if (list_empty(list))
738 			continue;
739 
740 		list_for_each_entry_rcu(e, list, list) {
741 			if ((e->rule.mask[word] & bit) == bit &&
742 			    audit_filter_rules(tsk, &e->rule, ctx, n, &state)) {
743 				rcu_read_unlock();
744 				ctx->current_state = state;
745 				return;
746 			}
747 		}
748 	}
749 	rcu_read_unlock();
750 }
751 
752 static inline struct audit_context *audit_get_context(struct task_struct *tsk,
753 						      int return_valid,
754 						      long return_code)
755 {
756 	struct audit_context *context = tsk->audit_context;
757 
758 	if (likely(!context))
759 		return NULL;
760 	context->return_valid = return_valid;
761 
762 	/*
763 	 * we need to fix up the return code in the audit logs if the actual
764 	 * return codes are later going to be fixed up by the arch specific
765 	 * signal handlers
766 	 *
767 	 * This is actually a test for:
768 	 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
769 	 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
770 	 *
771 	 * but is faster than a bunch of ||
772 	 */
773 	if (unlikely(return_code <= -ERESTARTSYS) &&
774 	    (return_code >= -ERESTART_RESTARTBLOCK) &&
775 	    (return_code != -ENOIOCTLCMD))
776 		context->return_code = -EINTR;
777 	else
778 		context->return_code  = return_code;
779 
780 	if (context->in_syscall && !context->dummy) {
781 		audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
782 		audit_filter_inodes(tsk, context);
783 	}
784 
785 	tsk->audit_context = NULL;
786 	return context;
787 }
788 
789 static inline void audit_free_names(struct audit_context *context)
790 {
791 	int i;
792 
793 #if AUDIT_DEBUG == 2
794 	if (context->put_count + context->ino_count != context->name_count) {
795 		printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
796 		       " name_count=%d put_count=%d"
797 		       " ino_count=%d [NOT freeing]\n",
798 		       __FILE__, __LINE__,
799 		       context->serial, context->major, context->in_syscall,
800 		       context->name_count, context->put_count,
801 		       context->ino_count);
802 		for (i = 0; i < context->name_count; i++) {
803 			printk(KERN_ERR "names[%d] = %p = %s\n", i,
804 			       context->names[i].name,
805 			       context->names[i].name ?: "(null)");
806 		}
807 		dump_stack();
808 		return;
809 	}
810 #endif
811 #if AUDIT_DEBUG
812 	context->put_count  = 0;
813 	context->ino_count  = 0;
814 #endif
815 
816 	for (i = 0; i < context->name_count; i++) {
817 		if (context->names[i].name && context->names[i].name_put)
818 			__putname(context->names[i].name);
819 	}
820 	context->name_count = 0;
821 	path_put(&context->pwd);
822 	context->pwd.dentry = NULL;
823 	context->pwd.mnt = NULL;
824 }
825 
826 static inline void audit_free_aux(struct audit_context *context)
827 {
828 	struct audit_aux_data *aux;
829 
830 	while ((aux = context->aux)) {
831 		context->aux = aux->next;
832 		kfree(aux);
833 	}
834 	while ((aux = context->aux_pids)) {
835 		context->aux_pids = aux->next;
836 		kfree(aux);
837 	}
838 }
839 
840 static inline void audit_zero_context(struct audit_context *context,
841 				      enum audit_state state)
842 {
843 	memset(context, 0, sizeof(*context));
844 	context->state      = state;
845 	context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
846 }
847 
848 static inline struct audit_context *audit_alloc_context(enum audit_state state)
849 {
850 	struct audit_context *context;
851 
852 	if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
853 		return NULL;
854 	audit_zero_context(context, state);
855 	INIT_LIST_HEAD(&context->killed_trees);
856 	return context;
857 }
858 
859 /**
860  * audit_alloc - allocate an audit context block for a task
861  * @tsk: task
862  *
863  * Filter on the task information and allocate a per-task audit context
864  * if necessary.  Doing so turns on system call auditing for the
865  * specified task.  This is called from copy_process, so no lock is
866  * needed.
867  */
868 int audit_alloc(struct task_struct *tsk)
869 {
870 	struct audit_context *context;
871 	enum audit_state     state;
872 	char *key = NULL;
873 
874 	if (likely(!audit_ever_enabled))
875 		return 0; /* Return if not auditing. */
876 
877 	state = audit_filter_task(tsk, &key);
878 	if (likely(state == AUDIT_DISABLED))
879 		return 0;
880 
881 	if (!(context = audit_alloc_context(state))) {
882 		kfree(key);
883 		audit_log_lost("out of memory in audit_alloc");
884 		return -ENOMEM;
885 	}
886 	context->filterkey = key;
887 
888 	tsk->audit_context  = context;
889 	set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
890 	return 0;
891 }
892 
893 static inline void audit_free_context(struct audit_context *context)
894 {
895 	struct audit_context *previous;
896 	int		     count = 0;
897 
898 	do {
899 		previous = context->previous;
900 		if (previous || (count &&  count < 10)) {
901 			++count;
902 			printk(KERN_ERR "audit(:%d): major=%d name_count=%d:"
903 			       " freeing multiple contexts (%d)\n",
904 			       context->serial, context->major,
905 			       context->name_count, count);
906 		}
907 		audit_free_names(context);
908 		unroll_tree_refs(context, NULL, 0);
909 		free_tree_refs(context);
910 		audit_free_aux(context);
911 		kfree(context->filterkey);
912 		kfree(context->sockaddr);
913 		kfree(context);
914 		context  = previous;
915 	} while (context);
916 	if (count >= 10)
917 		printk(KERN_ERR "audit: freed %d contexts\n", count);
918 }
919 
920 void audit_log_task_context(struct audit_buffer *ab)
921 {
922 	char *ctx = NULL;
923 	unsigned len;
924 	int error;
925 	u32 sid;
926 
927 	security_task_getsecid(current, &sid);
928 	if (!sid)
929 		return;
930 
931 	error = security_secid_to_secctx(sid, &ctx, &len);
932 	if (error) {
933 		if (error != -EINVAL)
934 			goto error_path;
935 		return;
936 	}
937 
938 	audit_log_format(ab, " subj=%s", ctx);
939 	security_release_secctx(ctx, len);
940 	return;
941 
942 error_path:
943 	audit_panic("error in audit_log_task_context");
944 	return;
945 }
946 
947 EXPORT_SYMBOL(audit_log_task_context);
948 
949 static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
950 {
951 	char name[sizeof(tsk->comm)];
952 	struct mm_struct *mm = tsk->mm;
953 	struct vm_area_struct *vma;
954 
955 	/* tsk == current */
956 
957 	get_task_comm(name, tsk);
958 	audit_log_format(ab, " comm=");
959 	audit_log_untrustedstring(ab, name);
960 
961 	if (mm) {
962 		down_read(&mm->mmap_sem);
963 		vma = mm->mmap;
964 		while (vma) {
965 			if ((vma->vm_flags & VM_EXECUTABLE) &&
966 			    vma->vm_file) {
967 				audit_log_d_path(ab, "exe=",
968 						 &vma->vm_file->f_path);
969 				break;
970 			}
971 			vma = vma->vm_next;
972 		}
973 		up_read(&mm->mmap_sem);
974 	}
975 	audit_log_task_context(ab);
976 }
977 
978 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
979 				 uid_t auid, uid_t uid, unsigned int sessionid,
980 				 u32 sid, char *comm)
981 {
982 	struct audit_buffer *ab;
983 	char *ctx = NULL;
984 	u32 len;
985 	int rc = 0;
986 
987 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
988 	if (!ab)
989 		return rc;
990 
991 	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid,
992 			 uid, sessionid);
993 	if (security_secid_to_secctx(sid, &ctx, &len)) {
994 		audit_log_format(ab, " obj=(none)");
995 		rc = 1;
996 	} else {
997 		audit_log_format(ab, " obj=%s", ctx);
998 		security_release_secctx(ctx, len);
999 	}
1000 	audit_log_format(ab, " ocomm=");
1001 	audit_log_untrustedstring(ab, comm);
1002 	audit_log_end(ab);
1003 
1004 	return rc;
1005 }
1006 
1007 /*
1008  * to_send and len_sent accounting are very loose estimates.  We aren't
1009  * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being
1010  * within about 500 bytes (next page boundry)
1011  *
1012  * why snprintf?  an int is up to 12 digits long.  if we just assumed when
1013  * logging that a[%d]= was going to be 16 characters long we would be wasting
1014  * space in every audit message.  In one 7500 byte message we can log up to
1015  * about 1000 min size arguments.  That comes down to about 50% waste of space
1016  * if we didn't do the snprintf to find out how long arg_num_len was.
1017  */
1018 static int audit_log_single_execve_arg(struct audit_context *context,
1019 					struct audit_buffer **ab,
1020 					int arg_num,
1021 					size_t *len_sent,
1022 					const char __user *p,
1023 					char *buf)
1024 {
1025 	char arg_num_len_buf[12];
1026 	const char __user *tmp_p = p;
1027 	/* how many digits are in arg_num? 5 is the length of ' a=""' */
1028 	size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 5;
1029 	size_t len, len_left, to_send;
1030 	size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN;
1031 	unsigned int i, has_cntl = 0, too_long = 0;
1032 	int ret;
1033 
1034 	/* strnlen_user includes the null we don't want to send */
1035 	len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1036 
1037 	/*
1038 	 * We just created this mm, if we can't find the strings
1039 	 * we just copied into it something is _very_ wrong. Similar
1040 	 * for strings that are too long, we should not have created
1041 	 * any.
1042 	 */
1043 	if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
1044 		WARN_ON(1);
1045 		send_sig(SIGKILL, current, 0);
1046 		return -1;
1047 	}
1048 
1049 	/* walk the whole argument looking for non-ascii chars */
1050 	do {
1051 		if (len_left > MAX_EXECVE_AUDIT_LEN)
1052 			to_send = MAX_EXECVE_AUDIT_LEN;
1053 		else
1054 			to_send = len_left;
1055 		ret = copy_from_user(buf, tmp_p, to_send);
1056 		/*
1057 		 * There is no reason for this copy to be short. We just
1058 		 * copied them here, and the mm hasn't been exposed to user-
1059 		 * space yet.
1060 		 */
1061 		if (ret) {
1062 			WARN_ON(1);
1063 			send_sig(SIGKILL, current, 0);
1064 			return -1;
1065 		}
1066 		buf[to_send] = '\0';
1067 		has_cntl = audit_string_contains_control(buf, to_send);
1068 		if (has_cntl) {
1069 			/*
1070 			 * hex messages get logged as 2 bytes, so we can only
1071 			 * send half as much in each message
1072 			 */
1073 			max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2;
1074 			break;
1075 		}
1076 		len_left -= to_send;
1077 		tmp_p += to_send;
1078 	} while (len_left > 0);
1079 
1080 	len_left = len;
1081 
1082 	if (len > max_execve_audit_len)
1083 		too_long = 1;
1084 
1085 	/* rewalk the argument actually logging the message */
1086 	for (i = 0; len_left > 0; i++) {
1087 		int room_left;
1088 
1089 		if (len_left > max_execve_audit_len)
1090 			to_send = max_execve_audit_len;
1091 		else
1092 			to_send = len_left;
1093 
1094 		/* do we have space left to send this argument in this ab? */
1095 		room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent;
1096 		if (has_cntl)
1097 			room_left -= (to_send * 2);
1098 		else
1099 			room_left -= to_send;
1100 		if (room_left < 0) {
1101 			*len_sent = 0;
1102 			audit_log_end(*ab);
1103 			*ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE);
1104 			if (!*ab)
1105 				return 0;
1106 		}
1107 
1108 		/*
1109 		 * first record needs to say how long the original string was
1110 		 * so we can be sure nothing was lost.
1111 		 */
1112 		if ((i == 0) && (too_long))
1113 			audit_log_format(*ab, " a%d_len=%zu", arg_num,
1114 					 has_cntl ? 2*len : len);
1115 
1116 		/*
1117 		 * normally arguments are small enough to fit and we already
1118 		 * filled buf above when we checked for control characters
1119 		 * so don't bother with another copy_from_user
1120 		 */
1121 		if (len >= max_execve_audit_len)
1122 			ret = copy_from_user(buf, p, to_send);
1123 		else
1124 			ret = 0;
1125 		if (ret) {
1126 			WARN_ON(1);
1127 			send_sig(SIGKILL, current, 0);
1128 			return -1;
1129 		}
1130 		buf[to_send] = '\0';
1131 
1132 		/* actually log it */
1133 		audit_log_format(*ab, " a%d", arg_num);
1134 		if (too_long)
1135 			audit_log_format(*ab, "[%d]", i);
1136 		audit_log_format(*ab, "=");
1137 		if (has_cntl)
1138 			audit_log_n_hex(*ab, buf, to_send);
1139 		else
1140 			audit_log_string(*ab, buf);
1141 
1142 		p += to_send;
1143 		len_left -= to_send;
1144 		*len_sent += arg_num_len;
1145 		if (has_cntl)
1146 			*len_sent += to_send * 2;
1147 		else
1148 			*len_sent += to_send;
1149 	}
1150 	/* include the null we didn't log */
1151 	return len + 1;
1152 }
1153 
1154 static void audit_log_execve_info(struct audit_context *context,
1155 				  struct audit_buffer **ab,
1156 				  struct audit_aux_data_execve *axi)
1157 {
1158 	int i;
1159 	size_t len, len_sent = 0;
1160 	const char __user *p;
1161 	char *buf;
1162 
1163 	if (axi->mm != current->mm)
1164 		return; /* execve failed, no additional info */
1165 
1166 	p = (const char __user *)axi->mm->arg_start;
1167 
1168 	audit_log_format(*ab, "argc=%d", axi->argc);
1169 
1170 	/*
1171 	 * we need some kernel buffer to hold the userspace args.  Just
1172 	 * allocate one big one rather than allocating one of the right size
1173 	 * for every single argument inside audit_log_single_execve_arg()
1174 	 * should be <8k allocation so should be pretty safe.
1175 	 */
1176 	buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1177 	if (!buf) {
1178 		audit_panic("out of memory for argv string\n");
1179 		return;
1180 	}
1181 
1182 	for (i = 0; i < axi->argc; i++) {
1183 		len = audit_log_single_execve_arg(context, ab, i,
1184 						  &len_sent, p, buf);
1185 		if (len <= 0)
1186 			break;
1187 		p += len;
1188 	}
1189 	kfree(buf);
1190 }
1191 
1192 static void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap)
1193 {
1194 	int i;
1195 
1196 	audit_log_format(ab, " %s=", prefix);
1197 	CAP_FOR_EACH_U32(i) {
1198 		audit_log_format(ab, "%08x", cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]);
1199 	}
1200 }
1201 
1202 static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
1203 {
1204 	kernel_cap_t *perm = &name->fcap.permitted;
1205 	kernel_cap_t *inh = &name->fcap.inheritable;
1206 	int log = 0;
1207 
1208 	if (!cap_isclear(*perm)) {
1209 		audit_log_cap(ab, "cap_fp", perm);
1210 		log = 1;
1211 	}
1212 	if (!cap_isclear(*inh)) {
1213 		audit_log_cap(ab, "cap_fi", inh);
1214 		log = 1;
1215 	}
1216 
1217 	if (log)
1218 		audit_log_format(ab, " cap_fe=%d cap_fver=%x", name->fcap.fE, name->fcap_ver);
1219 }
1220 
1221 static void show_special(struct audit_context *context, int *call_panic)
1222 {
1223 	struct audit_buffer *ab;
1224 	int i;
1225 
1226 	ab = audit_log_start(context, GFP_KERNEL, context->type);
1227 	if (!ab)
1228 		return;
1229 
1230 	switch (context->type) {
1231 	case AUDIT_SOCKETCALL: {
1232 		int nargs = context->socketcall.nargs;
1233 		audit_log_format(ab, "nargs=%d", nargs);
1234 		for (i = 0; i < nargs; i++)
1235 			audit_log_format(ab, " a%d=%lx", i,
1236 				context->socketcall.args[i]);
1237 		break; }
1238 	case AUDIT_IPC: {
1239 		u32 osid = context->ipc.osid;
1240 
1241 		audit_log_format(ab, "ouid=%u ogid=%u mode=%#o",
1242 			 context->ipc.uid, context->ipc.gid, context->ipc.mode);
1243 		if (osid) {
1244 			char *ctx = NULL;
1245 			u32 len;
1246 			if (security_secid_to_secctx(osid, &ctx, &len)) {
1247 				audit_log_format(ab, " osid=%u", osid);
1248 				*call_panic = 1;
1249 			} else {
1250 				audit_log_format(ab, " obj=%s", ctx);
1251 				security_release_secctx(ctx, len);
1252 			}
1253 		}
1254 		if (context->ipc.has_perm) {
1255 			audit_log_end(ab);
1256 			ab = audit_log_start(context, GFP_KERNEL,
1257 					     AUDIT_IPC_SET_PERM);
1258 			audit_log_format(ab,
1259 				"qbytes=%lx ouid=%u ogid=%u mode=%#o",
1260 				context->ipc.qbytes,
1261 				context->ipc.perm_uid,
1262 				context->ipc.perm_gid,
1263 				context->ipc.perm_mode);
1264 			if (!ab)
1265 				return;
1266 		}
1267 		break; }
1268 	case AUDIT_MQ_OPEN: {
1269 		audit_log_format(ab,
1270 			"oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld "
1271 			"mq_msgsize=%ld mq_curmsgs=%ld",
1272 			context->mq_open.oflag, context->mq_open.mode,
1273 			context->mq_open.attr.mq_flags,
1274 			context->mq_open.attr.mq_maxmsg,
1275 			context->mq_open.attr.mq_msgsize,
1276 			context->mq_open.attr.mq_curmsgs);
1277 		break; }
1278 	case AUDIT_MQ_SENDRECV: {
1279 		audit_log_format(ab,
1280 			"mqdes=%d msg_len=%zd msg_prio=%u "
1281 			"abs_timeout_sec=%ld abs_timeout_nsec=%ld",
1282 			context->mq_sendrecv.mqdes,
1283 			context->mq_sendrecv.msg_len,
1284 			context->mq_sendrecv.msg_prio,
1285 			context->mq_sendrecv.abs_timeout.tv_sec,
1286 			context->mq_sendrecv.abs_timeout.tv_nsec);
1287 		break; }
1288 	case AUDIT_MQ_NOTIFY: {
1289 		audit_log_format(ab, "mqdes=%d sigev_signo=%d",
1290 				context->mq_notify.mqdes,
1291 				context->mq_notify.sigev_signo);
1292 		break; }
1293 	case AUDIT_MQ_GETSETATTR: {
1294 		struct mq_attr *attr = &context->mq_getsetattr.mqstat;
1295 		audit_log_format(ab,
1296 			"mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1297 			"mq_curmsgs=%ld ",
1298 			context->mq_getsetattr.mqdes,
1299 			attr->mq_flags, attr->mq_maxmsg,
1300 			attr->mq_msgsize, attr->mq_curmsgs);
1301 		break; }
1302 	case AUDIT_CAPSET: {
1303 		audit_log_format(ab, "pid=%d", context->capset.pid);
1304 		audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
1305 		audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
1306 		audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
1307 		break; }
1308 	}
1309 	audit_log_end(ab);
1310 }
1311 
1312 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
1313 {
1314 	const struct cred *cred;
1315 	int i, call_panic = 0;
1316 	struct audit_buffer *ab;
1317 	struct audit_aux_data *aux;
1318 	const char *tty;
1319 
1320 	/* tsk == current */
1321 	context->pid = tsk->pid;
1322 	if (!context->ppid)
1323 		context->ppid = sys_getppid();
1324 	cred = current_cred();
1325 	context->uid   = cred->uid;
1326 	context->gid   = cred->gid;
1327 	context->euid  = cred->euid;
1328 	context->suid  = cred->suid;
1329 	context->fsuid = cred->fsuid;
1330 	context->egid  = cred->egid;
1331 	context->sgid  = cred->sgid;
1332 	context->fsgid = cred->fsgid;
1333 	context->personality = tsk->personality;
1334 
1335 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1336 	if (!ab)
1337 		return;		/* audit_panic has been called */
1338 	audit_log_format(ab, "arch=%x syscall=%d",
1339 			 context->arch, context->major);
1340 	if (context->personality != PER_LINUX)
1341 		audit_log_format(ab, " per=%lx", context->personality);
1342 	if (context->return_valid)
1343 		audit_log_format(ab, " success=%s exit=%ld",
1344 				 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
1345 				 context->return_code);
1346 
1347 	spin_lock_irq(&tsk->sighand->siglock);
1348 	if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
1349 		tty = tsk->signal->tty->name;
1350 	else
1351 		tty = "(none)";
1352 	spin_unlock_irq(&tsk->sighand->siglock);
1353 
1354 	audit_log_format(ab,
1355 		  " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
1356 		  " ppid=%d pid=%d auid=%u uid=%u gid=%u"
1357 		  " euid=%u suid=%u fsuid=%u"
1358 		  " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
1359 		  context->argv[0],
1360 		  context->argv[1],
1361 		  context->argv[2],
1362 		  context->argv[3],
1363 		  context->name_count,
1364 		  context->ppid,
1365 		  context->pid,
1366 		  tsk->loginuid,
1367 		  context->uid,
1368 		  context->gid,
1369 		  context->euid, context->suid, context->fsuid,
1370 		  context->egid, context->sgid, context->fsgid, tty,
1371 		  tsk->sessionid);
1372 
1373 
1374 	audit_log_task_info(ab, tsk);
1375 	audit_log_key(ab, context->filterkey);
1376 	audit_log_end(ab);
1377 
1378 	for (aux = context->aux; aux; aux = aux->next) {
1379 
1380 		ab = audit_log_start(context, GFP_KERNEL, aux->type);
1381 		if (!ab)
1382 			continue; /* audit_panic has been called */
1383 
1384 		switch (aux->type) {
1385 
1386 		case AUDIT_EXECVE: {
1387 			struct audit_aux_data_execve *axi = (void *)aux;
1388 			audit_log_execve_info(context, &ab, axi);
1389 			break; }
1390 
1391 		case AUDIT_BPRM_FCAPS: {
1392 			struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
1393 			audit_log_format(ab, "fver=%x", axs->fcap_ver);
1394 			audit_log_cap(ab, "fp", &axs->fcap.permitted);
1395 			audit_log_cap(ab, "fi", &axs->fcap.inheritable);
1396 			audit_log_format(ab, " fe=%d", axs->fcap.fE);
1397 			audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
1398 			audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
1399 			audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
1400 			audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted);
1401 			audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable);
1402 			audit_log_cap(ab, "new_pe", &axs->new_pcap.effective);
1403 			break; }
1404 
1405 		}
1406 		audit_log_end(ab);
1407 	}
1408 
1409 	if (context->type)
1410 		show_special(context, &call_panic);
1411 
1412 	if (context->fds[0] >= 0) {
1413 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
1414 		if (ab) {
1415 			audit_log_format(ab, "fd0=%d fd1=%d",
1416 					context->fds[0], context->fds[1]);
1417 			audit_log_end(ab);
1418 		}
1419 	}
1420 
1421 	if (context->sockaddr_len) {
1422 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
1423 		if (ab) {
1424 			audit_log_format(ab, "saddr=");
1425 			audit_log_n_hex(ab, (void *)context->sockaddr,
1426 					context->sockaddr_len);
1427 			audit_log_end(ab);
1428 		}
1429 	}
1430 
1431 	for (aux = context->aux_pids; aux; aux = aux->next) {
1432 		struct audit_aux_data_pids *axs = (void *)aux;
1433 
1434 		for (i = 0; i < axs->pid_count; i++)
1435 			if (audit_log_pid_context(context, axs->target_pid[i],
1436 						  axs->target_auid[i],
1437 						  axs->target_uid[i],
1438 						  axs->target_sessionid[i],
1439 						  axs->target_sid[i],
1440 						  axs->target_comm[i]))
1441 				call_panic = 1;
1442 	}
1443 
1444 	if (context->target_pid &&
1445 	    audit_log_pid_context(context, context->target_pid,
1446 				  context->target_auid, context->target_uid,
1447 				  context->target_sessionid,
1448 				  context->target_sid, context->target_comm))
1449 			call_panic = 1;
1450 
1451 	if (context->pwd.dentry && context->pwd.mnt) {
1452 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1453 		if (ab) {
1454 			audit_log_d_path(ab, "cwd=", &context->pwd);
1455 			audit_log_end(ab);
1456 		}
1457 	}
1458 	for (i = 0; i < context->name_count; i++) {
1459 		struct audit_names *n = &context->names[i];
1460 
1461 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1462 		if (!ab)
1463 			continue; /* audit_panic has been called */
1464 
1465 		audit_log_format(ab, "item=%d", i);
1466 
1467 		if (n->name) {
1468 			switch(n->name_len) {
1469 			case AUDIT_NAME_FULL:
1470 				/* log the full path */
1471 				audit_log_format(ab, " name=");
1472 				audit_log_untrustedstring(ab, n->name);
1473 				break;
1474 			case 0:
1475 				/* name was specified as a relative path and the
1476 				 * directory component is the cwd */
1477 				audit_log_d_path(ab, "name=", &context->pwd);
1478 				break;
1479 			default:
1480 				/* log the name's directory component */
1481 				audit_log_format(ab, " name=");
1482 				audit_log_n_untrustedstring(ab, n->name,
1483 							    n->name_len);
1484 			}
1485 		} else
1486 			audit_log_format(ab, " name=(null)");
1487 
1488 		if (n->ino != (unsigned long)-1) {
1489 			audit_log_format(ab, " inode=%lu"
1490 					 " dev=%02x:%02x mode=%#o"
1491 					 " ouid=%u ogid=%u rdev=%02x:%02x",
1492 					 n->ino,
1493 					 MAJOR(n->dev),
1494 					 MINOR(n->dev),
1495 					 n->mode,
1496 					 n->uid,
1497 					 n->gid,
1498 					 MAJOR(n->rdev),
1499 					 MINOR(n->rdev));
1500 		}
1501 		if (n->osid != 0) {
1502 			char *ctx = NULL;
1503 			u32 len;
1504 			if (security_secid_to_secctx(
1505 				n->osid, &ctx, &len)) {
1506 				audit_log_format(ab, " osid=%u", n->osid);
1507 				call_panic = 2;
1508 			} else {
1509 				audit_log_format(ab, " obj=%s", ctx);
1510 				security_release_secctx(ctx, len);
1511 			}
1512 		}
1513 
1514 		audit_log_fcaps(ab, n);
1515 
1516 		audit_log_end(ab);
1517 	}
1518 
1519 	/* Send end of event record to help user space know we are finished */
1520 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1521 	if (ab)
1522 		audit_log_end(ab);
1523 	if (call_panic)
1524 		audit_panic("error converting sid to string");
1525 }
1526 
1527 /**
1528  * audit_free - free a per-task audit context
1529  * @tsk: task whose audit context block to free
1530  *
1531  * Called from copy_process and do_exit
1532  */
1533 void audit_free(struct task_struct *tsk)
1534 {
1535 	struct audit_context *context;
1536 
1537 	context = audit_get_context(tsk, 0, 0);
1538 	if (likely(!context))
1539 		return;
1540 
1541 	/* Check for system calls that do not go through the exit
1542 	 * function (e.g., exit_group), then free context block.
1543 	 * We use GFP_ATOMIC here because we might be doing this
1544 	 * in the context of the idle thread */
1545 	/* that can happen only if we are called from do_exit() */
1546 	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1547 		audit_log_exit(context, tsk);
1548 	if (!list_empty(&context->killed_trees))
1549 		audit_kill_trees(&context->killed_trees);
1550 
1551 	audit_free_context(context);
1552 }
1553 
1554 /**
1555  * audit_syscall_entry - fill in an audit record at syscall entry
1556  * @arch: architecture type
1557  * @major: major syscall type (function)
1558  * @a1: additional syscall register 1
1559  * @a2: additional syscall register 2
1560  * @a3: additional syscall register 3
1561  * @a4: additional syscall register 4
1562  *
1563  * Fill in audit context at syscall entry.  This only happens if the
1564  * audit context was created when the task was created and the state or
1565  * filters demand the audit context be built.  If the state from the
1566  * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1567  * then the record will be written at syscall exit time (otherwise, it
1568  * will only be written if another part of the kernel requests that it
1569  * be written).
1570  */
1571 void audit_syscall_entry(int arch, int major,
1572 			 unsigned long a1, unsigned long a2,
1573 			 unsigned long a3, unsigned long a4)
1574 {
1575 	struct task_struct *tsk = current;
1576 	struct audit_context *context = tsk->audit_context;
1577 	enum audit_state     state;
1578 
1579 	if (unlikely(!context))
1580 		return;
1581 
1582 	/*
1583 	 * This happens only on certain architectures that make system
1584 	 * calls in kernel_thread via the entry.S interface, instead of
1585 	 * with direct calls.  (If you are porting to a new
1586 	 * architecture, hitting this condition can indicate that you
1587 	 * got the _exit/_leave calls backward in entry.S.)
1588 	 *
1589 	 * i386     no
1590 	 * x86_64   no
1591 	 * ppc64    yes (see arch/powerpc/platforms/iseries/misc.S)
1592 	 *
1593 	 * This also happens with vm86 emulation in a non-nested manner
1594 	 * (entries without exits), so this case must be caught.
1595 	 */
1596 	if (context->in_syscall) {
1597 		struct audit_context *newctx;
1598 
1599 #if AUDIT_DEBUG
1600 		printk(KERN_ERR
1601 		       "audit(:%d) pid=%d in syscall=%d;"
1602 		       " entering syscall=%d\n",
1603 		       context->serial, tsk->pid, context->major, major);
1604 #endif
1605 		newctx = audit_alloc_context(context->state);
1606 		if (newctx) {
1607 			newctx->previous   = context;
1608 			context		   = newctx;
1609 			tsk->audit_context = newctx;
1610 		} else	{
1611 			/* If we can't alloc a new context, the best we
1612 			 * can do is to leak memory (any pending putname
1613 			 * will be lost).  The only other alternative is
1614 			 * to abandon auditing. */
1615 			audit_zero_context(context, context->state);
1616 		}
1617 	}
1618 	BUG_ON(context->in_syscall || context->name_count);
1619 
1620 	if (!audit_enabled)
1621 		return;
1622 
1623 	context->arch	    = arch;
1624 	context->major      = major;
1625 	context->argv[0]    = a1;
1626 	context->argv[1]    = a2;
1627 	context->argv[2]    = a3;
1628 	context->argv[3]    = a4;
1629 
1630 	state = context->state;
1631 	context->dummy = !audit_n_rules;
1632 	if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
1633 		context->prio = 0;
1634 		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1635 	}
1636 	if (likely(state == AUDIT_DISABLED))
1637 		return;
1638 
1639 	context->serial     = 0;
1640 	context->ctime      = CURRENT_TIME;
1641 	context->in_syscall = 1;
1642 	context->current_state  = state;
1643 	context->ppid       = 0;
1644 }
1645 
1646 void audit_finish_fork(struct task_struct *child)
1647 {
1648 	struct audit_context *ctx = current->audit_context;
1649 	struct audit_context *p = child->audit_context;
1650 	if (!p || !ctx)
1651 		return;
1652 	if (!ctx->in_syscall || ctx->current_state != AUDIT_RECORD_CONTEXT)
1653 		return;
1654 	p->arch = ctx->arch;
1655 	p->major = ctx->major;
1656 	memcpy(p->argv, ctx->argv, sizeof(ctx->argv));
1657 	p->ctime = ctx->ctime;
1658 	p->dummy = ctx->dummy;
1659 	p->in_syscall = ctx->in_syscall;
1660 	p->filterkey = kstrdup(ctx->filterkey, GFP_KERNEL);
1661 	p->ppid = current->pid;
1662 	p->prio = ctx->prio;
1663 	p->current_state = ctx->current_state;
1664 }
1665 
1666 /**
1667  * audit_syscall_exit - deallocate audit context after a system call
1668  * @valid: success/failure flag
1669  * @return_code: syscall return value
1670  *
1671  * Tear down after system call.  If the audit context has been marked as
1672  * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1673  * filtering, or because some other part of the kernel write an audit
1674  * message), then write out the syscall information.  In call cases,
1675  * free the names stored from getname().
1676  */
1677 void audit_syscall_exit(int valid, long return_code)
1678 {
1679 	struct task_struct *tsk = current;
1680 	struct audit_context *context;
1681 
1682 	context = audit_get_context(tsk, valid, return_code);
1683 
1684 	if (likely(!context))
1685 		return;
1686 
1687 	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1688 		audit_log_exit(context, tsk);
1689 
1690 	context->in_syscall = 0;
1691 	context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
1692 
1693 	if (!list_empty(&context->killed_trees))
1694 		audit_kill_trees(&context->killed_trees);
1695 
1696 	if (context->previous) {
1697 		struct audit_context *new_context = context->previous;
1698 		context->previous  = NULL;
1699 		audit_free_context(context);
1700 		tsk->audit_context = new_context;
1701 	} else {
1702 		audit_free_names(context);
1703 		unroll_tree_refs(context, NULL, 0);
1704 		audit_free_aux(context);
1705 		context->aux = NULL;
1706 		context->aux_pids = NULL;
1707 		context->target_pid = 0;
1708 		context->target_sid = 0;
1709 		context->sockaddr_len = 0;
1710 		context->type = 0;
1711 		context->fds[0] = -1;
1712 		if (context->state != AUDIT_RECORD_CONTEXT) {
1713 			kfree(context->filterkey);
1714 			context->filterkey = NULL;
1715 		}
1716 		tsk->audit_context = context;
1717 	}
1718 }
1719 
1720 static inline void handle_one(const struct inode *inode)
1721 {
1722 #ifdef CONFIG_AUDIT_TREE
1723 	struct audit_context *context;
1724 	struct audit_tree_refs *p;
1725 	struct audit_chunk *chunk;
1726 	int count;
1727 	if (likely(hlist_empty(&inode->i_fsnotify_marks)))
1728 		return;
1729 	context = current->audit_context;
1730 	p = context->trees;
1731 	count = context->tree_count;
1732 	rcu_read_lock();
1733 	chunk = audit_tree_lookup(inode);
1734 	rcu_read_unlock();
1735 	if (!chunk)
1736 		return;
1737 	if (likely(put_tree_ref(context, chunk)))
1738 		return;
1739 	if (unlikely(!grow_tree_refs(context))) {
1740 		printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
1741 		audit_set_auditable(context);
1742 		audit_put_chunk(chunk);
1743 		unroll_tree_refs(context, p, count);
1744 		return;
1745 	}
1746 	put_tree_ref(context, chunk);
1747 #endif
1748 }
1749 
1750 static void handle_path(const struct dentry *dentry)
1751 {
1752 #ifdef CONFIG_AUDIT_TREE
1753 	struct audit_context *context;
1754 	struct audit_tree_refs *p;
1755 	const struct dentry *d, *parent;
1756 	struct audit_chunk *drop;
1757 	unsigned long seq;
1758 	int count;
1759 
1760 	context = current->audit_context;
1761 	p = context->trees;
1762 	count = context->tree_count;
1763 retry:
1764 	drop = NULL;
1765 	d = dentry;
1766 	rcu_read_lock();
1767 	seq = read_seqbegin(&rename_lock);
1768 	for(;;) {
1769 		struct inode *inode = d->d_inode;
1770 		if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) {
1771 			struct audit_chunk *chunk;
1772 			chunk = audit_tree_lookup(inode);
1773 			if (chunk) {
1774 				if (unlikely(!put_tree_ref(context, chunk))) {
1775 					drop = chunk;
1776 					break;
1777 				}
1778 			}
1779 		}
1780 		parent = d->d_parent;
1781 		if (parent == d)
1782 			break;
1783 		d = parent;
1784 	}
1785 	if (unlikely(read_seqretry(&rename_lock, seq) || drop)) {  /* in this order */
1786 		rcu_read_unlock();
1787 		if (!drop) {
1788 			/* just a race with rename */
1789 			unroll_tree_refs(context, p, count);
1790 			goto retry;
1791 		}
1792 		audit_put_chunk(drop);
1793 		if (grow_tree_refs(context)) {
1794 			/* OK, got more space */
1795 			unroll_tree_refs(context, p, count);
1796 			goto retry;
1797 		}
1798 		/* too bad */
1799 		printk(KERN_WARNING
1800 			"out of memory, audit has lost a tree reference\n");
1801 		unroll_tree_refs(context, p, count);
1802 		audit_set_auditable(context);
1803 		return;
1804 	}
1805 	rcu_read_unlock();
1806 #endif
1807 }
1808 
1809 /**
1810  * audit_getname - add a name to the list
1811  * @name: name to add
1812  *
1813  * Add a name to the list of audit names for this context.
1814  * Called from fs/namei.c:getname().
1815  */
1816 void __audit_getname(const char *name)
1817 {
1818 	struct audit_context *context = current->audit_context;
1819 
1820 	if (IS_ERR(name) || !name)
1821 		return;
1822 
1823 	if (!context->in_syscall) {
1824 #if AUDIT_DEBUG == 2
1825 		printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
1826 		       __FILE__, __LINE__, context->serial, name);
1827 		dump_stack();
1828 #endif
1829 		return;
1830 	}
1831 	BUG_ON(context->name_count >= AUDIT_NAMES);
1832 	context->names[context->name_count].name = name;
1833 	context->names[context->name_count].name_len = AUDIT_NAME_FULL;
1834 	context->names[context->name_count].name_put = 1;
1835 	context->names[context->name_count].ino  = (unsigned long)-1;
1836 	context->names[context->name_count].osid = 0;
1837 	++context->name_count;
1838 	if (!context->pwd.dentry)
1839 		get_fs_pwd(current->fs, &context->pwd);
1840 }
1841 
1842 /* audit_putname - intercept a putname request
1843  * @name: name to intercept and delay for putname
1844  *
1845  * If we have stored the name from getname in the audit context,
1846  * then we delay the putname until syscall exit.
1847  * Called from include/linux/fs.h:putname().
1848  */
1849 void audit_putname(const char *name)
1850 {
1851 	struct audit_context *context = current->audit_context;
1852 
1853 	BUG_ON(!context);
1854 	if (!context->in_syscall) {
1855 #if AUDIT_DEBUG == 2
1856 		printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n",
1857 		       __FILE__, __LINE__, context->serial, name);
1858 		if (context->name_count) {
1859 			int i;
1860 			for (i = 0; i < context->name_count; i++)
1861 				printk(KERN_ERR "name[%d] = %p = %s\n", i,
1862 				       context->names[i].name,
1863 				       context->names[i].name ?: "(null)");
1864 		}
1865 #endif
1866 		__putname(name);
1867 	}
1868 #if AUDIT_DEBUG
1869 	else {
1870 		++context->put_count;
1871 		if (context->put_count > context->name_count) {
1872 			printk(KERN_ERR "%s:%d(:%d): major=%d"
1873 			       " in_syscall=%d putname(%p) name_count=%d"
1874 			       " put_count=%d\n",
1875 			       __FILE__, __LINE__,
1876 			       context->serial, context->major,
1877 			       context->in_syscall, name, context->name_count,
1878 			       context->put_count);
1879 			dump_stack();
1880 		}
1881 	}
1882 #endif
1883 }
1884 
1885 static int audit_inc_name_count(struct audit_context *context,
1886 				const struct inode *inode)
1887 {
1888 	if (context->name_count >= AUDIT_NAMES) {
1889 		if (inode)
1890 			printk(KERN_DEBUG "audit: name_count maxed, losing inode data: "
1891 			       "dev=%02x:%02x, inode=%lu\n",
1892 			       MAJOR(inode->i_sb->s_dev),
1893 			       MINOR(inode->i_sb->s_dev),
1894 			       inode->i_ino);
1895 
1896 		else
1897 			printk(KERN_DEBUG "name_count maxed, losing inode data\n");
1898 		return 1;
1899 	}
1900 	context->name_count++;
1901 #if AUDIT_DEBUG
1902 	context->ino_count++;
1903 #endif
1904 	return 0;
1905 }
1906 
1907 
1908 static inline int audit_copy_fcaps(struct audit_names *name, const struct dentry *dentry)
1909 {
1910 	struct cpu_vfs_cap_data caps;
1911 	int rc;
1912 
1913 	memset(&name->fcap.permitted, 0, sizeof(kernel_cap_t));
1914 	memset(&name->fcap.inheritable, 0, sizeof(kernel_cap_t));
1915 	name->fcap.fE = 0;
1916 	name->fcap_ver = 0;
1917 
1918 	if (!dentry)
1919 		return 0;
1920 
1921 	rc = get_vfs_caps_from_disk(dentry, &caps);
1922 	if (rc)
1923 		return rc;
1924 
1925 	name->fcap.permitted = caps.permitted;
1926 	name->fcap.inheritable = caps.inheritable;
1927 	name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
1928 	name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
1929 
1930 	return 0;
1931 }
1932 
1933 
1934 /* Copy inode data into an audit_names. */
1935 static void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
1936 			     const struct inode *inode)
1937 {
1938 	name->ino   = inode->i_ino;
1939 	name->dev   = inode->i_sb->s_dev;
1940 	name->mode  = inode->i_mode;
1941 	name->uid   = inode->i_uid;
1942 	name->gid   = inode->i_gid;
1943 	name->rdev  = inode->i_rdev;
1944 	security_inode_getsecid(inode, &name->osid);
1945 	audit_copy_fcaps(name, dentry);
1946 }
1947 
1948 /**
1949  * audit_inode - store the inode and device from a lookup
1950  * @name: name being audited
1951  * @dentry: dentry being audited
1952  *
1953  * Called from fs/namei.c:path_lookup().
1954  */
1955 void __audit_inode(const char *name, const struct dentry *dentry)
1956 {
1957 	int idx;
1958 	struct audit_context *context = current->audit_context;
1959 	const struct inode *inode = dentry->d_inode;
1960 
1961 	if (!context->in_syscall)
1962 		return;
1963 	if (context->name_count
1964 	    && context->names[context->name_count-1].name
1965 	    && context->names[context->name_count-1].name == name)
1966 		idx = context->name_count - 1;
1967 	else if (context->name_count > 1
1968 		 && context->names[context->name_count-2].name
1969 		 && context->names[context->name_count-2].name == name)
1970 		idx = context->name_count - 2;
1971 	else {
1972 		/* FIXME: how much do we care about inodes that have no
1973 		 * associated name? */
1974 		if (audit_inc_name_count(context, inode))
1975 			return;
1976 		idx = context->name_count - 1;
1977 		context->names[idx].name = NULL;
1978 	}
1979 	handle_path(dentry);
1980 	audit_copy_inode(&context->names[idx], dentry, inode);
1981 }
1982 
1983 /**
1984  * audit_inode_child - collect inode info for created/removed objects
1985  * @dentry: dentry being audited
1986  * @parent: inode of dentry parent
1987  *
1988  * For syscalls that create or remove filesystem objects, audit_inode
1989  * can only collect information for the filesystem object's parent.
1990  * This call updates the audit context with the child's information.
1991  * Syscalls that create a new filesystem object must be hooked after
1992  * the object is created.  Syscalls that remove a filesystem object
1993  * must be hooked prior, in order to capture the target inode during
1994  * unsuccessful attempts.
1995  */
1996 void __audit_inode_child(const struct dentry *dentry,
1997 			 const struct inode *parent)
1998 {
1999 	int idx;
2000 	struct audit_context *context = current->audit_context;
2001 	const char *found_parent = NULL, *found_child = NULL;
2002 	const struct inode *inode = dentry->d_inode;
2003 	const char *dname = dentry->d_name.name;
2004 	int dirlen = 0;
2005 
2006 	if (!context->in_syscall)
2007 		return;
2008 
2009 	if (inode)
2010 		handle_one(inode);
2011 
2012 	/* parent is more likely, look for it first */
2013 	for (idx = 0; idx < context->name_count; idx++) {
2014 		struct audit_names *n = &context->names[idx];
2015 
2016 		if (!n->name)
2017 			continue;
2018 
2019 		if (n->ino == parent->i_ino &&
2020 		    !audit_compare_dname_path(dname, n->name, &dirlen)) {
2021 			n->name_len = dirlen; /* update parent data in place */
2022 			found_parent = n->name;
2023 			goto add_names;
2024 		}
2025 	}
2026 
2027 	/* no matching parent, look for matching child */
2028 	for (idx = 0; idx < context->name_count; idx++) {
2029 		struct audit_names *n = &context->names[idx];
2030 
2031 		if (!n->name)
2032 			continue;
2033 
2034 		/* strcmp() is the more likely scenario */
2035 		if (!strcmp(dname, n->name) ||
2036 		     !audit_compare_dname_path(dname, n->name, &dirlen)) {
2037 			if (inode)
2038 				audit_copy_inode(n, NULL, inode);
2039 			else
2040 				n->ino = (unsigned long)-1;
2041 			found_child = n->name;
2042 			goto add_names;
2043 		}
2044 	}
2045 
2046 add_names:
2047 	if (!found_parent) {
2048 		if (audit_inc_name_count(context, parent))
2049 			return;
2050 		idx = context->name_count - 1;
2051 		context->names[idx].name = NULL;
2052 		audit_copy_inode(&context->names[idx], NULL, parent);
2053 	}
2054 
2055 	if (!found_child) {
2056 		if (audit_inc_name_count(context, inode))
2057 			return;
2058 		idx = context->name_count - 1;
2059 
2060 		/* Re-use the name belonging to the slot for a matching parent
2061 		 * directory. All names for this context are relinquished in
2062 		 * audit_free_names() */
2063 		if (found_parent) {
2064 			context->names[idx].name = found_parent;
2065 			context->names[idx].name_len = AUDIT_NAME_FULL;
2066 			/* don't call __putname() */
2067 			context->names[idx].name_put = 0;
2068 		} else {
2069 			context->names[idx].name = NULL;
2070 		}
2071 
2072 		if (inode)
2073 			audit_copy_inode(&context->names[idx], NULL, inode);
2074 		else
2075 			context->names[idx].ino = (unsigned long)-1;
2076 	}
2077 }
2078 EXPORT_SYMBOL_GPL(__audit_inode_child);
2079 
2080 /**
2081  * auditsc_get_stamp - get local copies of audit_context values
2082  * @ctx: audit_context for the task
2083  * @t: timespec to store time recorded in the audit_context
2084  * @serial: serial value that is recorded in the audit_context
2085  *
2086  * Also sets the context as auditable.
2087  */
2088 int auditsc_get_stamp(struct audit_context *ctx,
2089 		       struct timespec *t, unsigned int *serial)
2090 {
2091 	if (!ctx->in_syscall)
2092 		return 0;
2093 	if (!ctx->serial)
2094 		ctx->serial = audit_serial();
2095 	t->tv_sec  = ctx->ctime.tv_sec;
2096 	t->tv_nsec = ctx->ctime.tv_nsec;
2097 	*serial    = ctx->serial;
2098 	if (!ctx->prio) {
2099 		ctx->prio = 1;
2100 		ctx->current_state = AUDIT_RECORD_CONTEXT;
2101 	}
2102 	return 1;
2103 }
2104 
2105 /* global counter which is incremented every time something logs in */
2106 static atomic_t session_id = ATOMIC_INIT(0);
2107 
2108 /**
2109  * audit_set_loginuid - set a task's audit_context loginuid
2110  * @task: task whose audit context is being modified
2111  * @loginuid: loginuid value
2112  *
2113  * Returns 0.
2114  *
2115  * Called (set) from fs/proc/base.c::proc_loginuid_write().
2116  */
2117 int audit_set_loginuid(struct task_struct *task, uid_t loginuid)
2118 {
2119 	unsigned int sessionid = atomic_inc_return(&session_id);
2120 	struct audit_context *context = task->audit_context;
2121 
2122 	if (context && context->in_syscall) {
2123 		struct audit_buffer *ab;
2124 
2125 		ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
2126 		if (ab) {
2127 			audit_log_format(ab, "login pid=%d uid=%u "
2128 				"old auid=%u new auid=%u"
2129 				" old ses=%u new ses=%u",
2130 				task->pid, task_uid(task),
2131 				task->loginuid, loginuid,
2132 				task->sessionid, sessionid);
2133 			audit_log_end(ab);
2134 		}
2135 	}
2136 	task->sessionid = sessionid;
2137 	task->loginuid = loginuid;
2138 	return 0;
2139 }
2140 
2141 /**
2142  * __audit_mq_open - record audit data for a POSIX MQ open
2143  * @oflag: open flag
2144  * @mode: mode bits
2145  * @attr: queue attributes
2146  *
2147  */
2148 void __audit_mq_open(int oflag, mode_t mode, struct mq_attr *attr)
2149 {
2150 	struct audit_context *context = current->audit_context;
2151 
2152 	if (attr)
2153 		memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
2154 	else
2155 		memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2156 
2157 	context->mq_open.oflag = oflag;
2158 	context->mq_open.mode = mode;
2159 
2160 	context->type = AUDIT_MQ_OPEN;
2161 }
2162 
2163 /**
2164  * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2165  * @mqdes: MQ descriptor
2166  * @msg_len: Message length
2167  * @msg_prio: Message priority
2168  * @abs_timeout: Message timeout in absolute time
2169  *
2170  */
2171 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2172 			const struct timespec *abs_timeout)
2173 {
2174 	struct audit_context *context = current->audit_context;
2175 	struct timespec *p = &context->mq_sendrecv.abs_timeout;
2176 
2177 	if (abs_timeout)
2178 		memcpy(p, abs_timeout, sizeof(struct timespec));
2179 	else
2180 		memset(p, 0, sizeof(struct timespec));
2181 
2182 	context->mq_sendrecv.mqdes = mqdes;
2183 	context->mq_sendrecv.msg_len = msg_len;
2184 	context->mq_sendrecv.msg_prio = msg_prio;
2185 
2186 	context->type = AUDIT_MQ_SENDRECV;
2187 }
2188 
2189 /**
2190  * __audit_mq_notify - record audit data for a POSIX MQ notify
2191  * @mqdes: MQ descriptor
2192  * @notification: Notification event
2193  *
2194  */
2195 
2196 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2197 {
2198 	struct audit_context *context = current->audit_context;
2199 
2200 	if (notification)
2201 		context->mq_notify.sigev_signo = notification->sigev_signo;
2202 	else
2203 		context->mq_notify.sigev_signo = 0;
2204 
2205 	context->mq_notify.mqdes = mqdes;
2206 	context->type = AUDIT_MQ_NOTIFY;
2207 }
2208 
2209 /**
2210  * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2211  * @mqdes: MQ descriptor
2212  * @mqstat: MQ flags
2213  *
2214  */
2215 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2216 {
2217 	struct audit_context *context = current->audit_context;
2218 	context->mq_getsetattr.mqdes = mqdes;
2219 	context->mq_getsetattr.mqstat = *mqstat;
2220 	context->type = AUDIT_MQ_GETSETATTR;
2221 }
2222 
2223 /**
2224  * audit_ipc_obj - record audit data for ipc object
2225  * @ipcp: ipc permissions
2226  *
2227  */
2228 void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2229 {
2230 	struct audit_context *context = current->audit_context;
2231 	context->ipc.uid = ipcp->uid;
2232 	context->ipc.gid = ipcp->gid;
2233 	context->ipc.mode = ipcp->mode;
2234 	context->ipc.has_perm = 0;
2235 	security_ipc_getsecid(ipcp, &context->ipc.osid);
2236 	context->type = AUDIT_IPC;
2237 }
2238 
2239 /**
2240  * audit_ipc_set_perm - record audit data for new ipc permissions
2241  * @qbytes: msgq bytes
2242  * @uid: msgq user id
2243  * @gid: msgq group id
2244  * @mode: msgq mode (permissions)
2245  *
2246  * Called only after audit_ipc_obj().
2247  */
2248 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode)
2249 {
2250 	struct audit_context *context = current->audit_context;
2251 
2252 	context->ipc.qbytes = qbytes;
2253 	context->ipc.perm_uid = uid;
2254 	context->ipc.perm_gid = gid;
2255 	context->ipc.perm_mode = mode;
2256 	context->ipc.has_perm = 1;
2257 }
2258 
2259 int audit_bprm(struct linux_binprm *bprm)
2260 {
2261 	struct audit_aux_data_execve *ax;
2262 	struct audit_context *context = current->audit_context;
2263 
2264 	if (likely(!audit_enabled || !context || context->dummy))
2265 		return 0;
2266 
2267 	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2268 	if (!ax)
2269 		return -ENOMEM;
2270 
2271 	ax->argc = bprm->argc;
2272 	ax->envc = bprm->envc;
2273 	ax->mm = bprm->mm;
2274 	ax->d.type = AUDIT_EXECVE;
2275 	ax->d.next = context->aux;
2276 	context->aux = (void *)ax;
2277 	return 0;
2278 }
2279 
2280 
2281 /**
2282  * audit_socketcall - record audit data for sys_socketcall
2283  * @nargs: number of args
2284  * @args: args array
2285  *
2286  */
2287 void audit_socketcall(int nargs, unsigned long *args)
2288 {
2289 	struct audit_context *context = current->audit_context;
2290 
2291 	if (likely(!context || context->dummy))
2292 		return;
2293 
2294 	context->type = AUDIT_SOCKETCALL;
2295 	context->socketcall.nargs = nargs;
2296 	memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
2297 }
2298 
2299 /**
2300  * __audit_fd_pair - record audit data for pipe and socketpair
2301  * @fd1: the first file descriptor
2302  * @fd2: the second file descriptor
2303  *
2304  */
2305 void __audit_fd_pair(int fd1, int fd2)
2306 {
2307 	struct audit_context *context = current->audit_context;
2308 	context->fds[0] = fd1;
2309 	context->fds[1] = fd2;
2310 }
2311 
2312 /**
2313  * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2314  * @len: data length in user space
2315  * @a: data address in kernel space
2316  *
2317  * Returns 0 for success or NULL context or < 0 on error.
2318  */
2319 int audit_sockaddr(int len, void *a)
2320 {
2321 	struct audit_context *context = current->audit_context;
2322 
2323 	if (likely(!context || context->dummy))
2324 		return 0;
2325 
2326 	if (!context->sockaddr) {
2327 		void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
2328 		if (!p)
2329 			return -ENOMEM;
2330 		context->sockaddr = p;
2331 	}
2332 
2333 	context->sockaddr_len = len;
2334 	memcpy(context->sockaddr, a, len);
2335 	return 0;
2336 }
2337 
2338 void __audit_ptrace(struct task_struct *t)
2339 {
2340 	struct audit_context *context = current->audit_context;
2341 
2342 	context->target_pid = t->pid;
2343 	context->target_auid = audit_get_loginuid(t);
2344 	context->target_uid = task_uid(t);
2345 	context->target_sessionid = audit_get_sessionid(t);
2346 	security_task_getsecid(t, &context->target_sid);
2347 	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
2348 }
2349 
2350 /**
2351  * audit_signal_info - record signal info for shutting down audit subsystem
2352  * @sig: signal value
2353  * @t: task being signaled
2354  *
2355  * If the audit subsystem is being terminated, record the task (pid)
2356  * and uid that is doing that.
2357  */
2358 int __audit_signal_info(int sig, struct task_struct *t)
2359 {
2360 	struct audit_aux_data_pids *axp;
2361 	struct task_struct *tsk = current;
2362 	struct audit_context *ctx = tsk->audit_context;
2363 	uid_t uid = current_uid(), t_uid = task_uid(t);
2364 
2365 	if (audit_pid && t->tgid == audit_pid) {
2366 		if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
2367 			audit_sig_pid = tsk->pid;
2368 			if (tsk->loginuid != -1)
2369 				audit_sig_uid = tsk->loginuid;
2370 			else
2371 				audit_sig_uid = uid;
2372 			security_task_getsecid(tsk, &audit_sig_sid);
2373 		}
2374 		if (!audit_signals || audit_dummy_context())
2375 			return 0;
2376 	}
2377 
2378 	/* optimize the common case by putting first signal recipient directly
2379 	 * in audit_context */
2380 	if (!ctx->target_pid) {
2381 		ctx->target_pid = t->tgid;
2382 		ctx->target_auid = audit_get_loginuid(t);
2383 		ctx->target_uid = t_uid;
2384 		ctx->target_sessionid = audit_get_sessionid(t);
2385 		security_task_getsecid(t, &ctx->target_sid);
2386 		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
2387 		return 0;
2388 	}
2389 
2390 	axp = (void *)ctx->aux_pids;
2391 	if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2392 		axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2393 		if (!axp)
2394 			return -ENOMEM;
2395 
2396 		axp->d.type = AUDIT_OBJ_PID;
2397 		axp->d.next = ctx->aux_pids;
2398 		ctx->aux_pids = (void *)axp;
2399 	}
2400 	BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2401 
2402 	axp->target_pid[axp->pid_count] = t->tgid;
2403 	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2404 	axp->target_uid[axp->pid_count] = t_uid;
2405 	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2406 	security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2407 	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
2408 	axp->pid_count++;
2409 
2410 	return 0;
2411 }
2412 
2413 /**
2414  * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
2415  * @bprm: pointer to the bprm being processed
2416  * @new: the proposed new credentials
2417  * @old: the old credentials
2418  *
2419  * Simply check if the proc already has the caps given by the file and if not
2420  * store the priv escalation info for later auditing at the end of the syscall
2421  *
2422  * -Eric
2423  */
2424 int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
2425 			   const struct cred *new, const struct cred *old)
2426 {
2427 	struct audit_aux_data_bprm_fcaps *ax;
2428 	struct audit_context *context = current->audit_context;
2429 	struct cpu_vfs_cap_data vcaps;
2430 	struct dentry *dentry;
2431 
2432 	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2433 	if (!ax)
2434 		return -ENOMEM;
2435 
2436 	ax->d.type = AUDIT_BPRM_FCAPS;
2437 	ax->d.next = context->aux;
2438 	context->aux = (void *)ax;
2439 
2440 	dentry = dget(bprm->file->f_dentry);
2441 	get_vfs_caps_from_disk(dentry, &vcaps);
2442 	dput(dentry);
2443 
2444 	ax->fcap.permitted = vcaps.permitted;
2445 	ax->fcap.inheritable = vcaps.inheritable;
2446 	ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2447 	ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
2448 
2449 	ax->old_pcap.permitted   = old->cap_permitted;
2450 	ax->old_pcap.inheritable = old->cap_inheritable;
2451 	ax->old_pcap.effective   = old->cap_effective;
2452 
2453 	ax->new_pcap.permitted   = new->cap_permitted;
2454 	ax->new_pcap.inheritable = new->cap_inheritable;
2455 	ax->new_pcap.effective   = new->cap_effective;
2456 	return 0;
2457 }
2458 
2459 /**
2460  * __audit_log_capset - store information about the arguments to the capset syscall
2461  * @pid: target pid of the capset call
2462  * @new: the new credentials
2463  * @old: the old (current) credentials
2464  *
2465  * Record the aguments userspace sent to sys_capset for later printing by the
2466  * audit system if applicable
2467  */
2468 void __audit_log_capset(pid_t pid,
2469 		       const struct cred *new, const struct cred *old)
2470 {
2471 	struct audit_context *context = current->audit_context;
2472 	context->capset.pid = pid;
2473 	context->capset.cap.effective   = new->cap_effective;
2474 	context->capset.cap.inheritable = new->cap_effective;
2475 	context->capset.cap.permitted   = new->cap_permitted;
2476 	context->type = AUDIT_CAPSET;
2477 }
2478 
2479 /**
2480  * audit_core_dumps - record information about processes that end abnormally
2481  * @signr: signal value
2482  *
2483  * If a process ends with a core dump, something fishy is going on and we
2484  * should record the event for investigation.
2485  */
2486 void audit_core_dumps(long signr)
2487 {
2488 	struct audit_buffer *ab;
2489 	u32 sid;
2490 	uid_t auid = audit_get_loginuid(current), uid;
2491 	gid_t gid;
2492 	unsigned int sessionid = audit_get_sessionid(current);
2493 
2494 	if (!audit_enabled)
2495 		return;
2496 
2497 	if (signr == SIGQUIT)	/* don't care for those */
2498 		return;
2499 
2500 	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2501 	current_uid_gid(&uid, &gid);
2502 	audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2503 			 auid, uid, gid, sessionid);
2504 	security_task_getsecid(current, &sid);
2505 	if (sid) {
2506 		char *ctx = NULL;
2507 		u32 len;
2508 
2509 		if (security_secid_to_secctx(sid, &ctx, &len))
2510 			audit_log_format(ab, " ssid=%u", sid);
2511 		else {
2512 			audit_log_format(ab, " subj=%s", ctx);
2513 			security_release_secctx(ctx, len);
2514 		}
2515 	}
2516 	audit_log_format(ab, " pid=%d comm=", current->pid);
2517 	audit_log_untrustedstring(ab, current->comm);
2518 	audit_log_format(ab, " sig=%ld", signr);
2519 	audit_log_end(ab);
2520 }
2521 
2522 struct list_head *audit_killed_trees(void)
2523 {
2524 	struct audit_context *ctx = current->audit_context;
2525 	if (likely(!ctx || !ctx->in_syscall))
2526 		return NULL;
2527 	return &ctx->killed_trees;
2528 }
2529