xref: /linux/kernel/auditsc.c (revision f24e9f586b377749dff37554696cf3a105540c94)
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 <asm/types.h>
49 #include <linux/fs.h>
50 #include <linux/namei.h>
51 #include <linux/mm.h>
52 #include <linux/module.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/selinux.h>
66 #include <linux/binfmts.h>
67 #include <linux/syscalls.h>
68 
69 #include "audit.h"
70 
71 extern struct list_head audit_filter_list[];
72 
73 /* No syscall auditing will take place unless audit_enabled != 0. */
74 extern int audit_enabled;
75 
76 /* AUDIT_NAMES is the number of slots we reserve in the audit_context
77  * for saving names from getname(). */
78 #define AUDIT_NAMES    20
79 
80 /* AUDIT_NAMES_RESERVED is the number of slots we reserve in the
81  * audit_context from being used for nameless inodes from
82  * path_lookup. */
83 #define AUDIT_NAMES_RESERVED 7
84 
85 /* Indicates that audit should log the full pathname. */
86 #define AUDIT_NAME_FULL -1
87 
88 /* number of audit rules */
89 int audit_n_rules;
90 
91 /* When fs/namei.c:getname() is called, we store the pointer in name and
92  * we don't let putname() free it (instead we free all of the saved
93  * pointers at syscall exit time).
94  *
95  * Further, in fs/namei.c:path_lookup() we store the inode and device. */
96 struct audit_names {
97 	const char	*name;
98 	int		name_len;	/* number of name's characters to log */
99 	unsigned	name_put;	/* call __putname() for this name */
100 	unsigned long	ino;
101 	dev_t		dev;
102 	umode_t		mode;
103 	uid_t		uid;
104 	gid_t		gid;
105 	dev_t		rdev;
106 	u32		osid;
107 };
108 
109 struct audit_aux_data {
110 	struct audit_aux_data	*next;
111 	int			type;
112 };
113 
114 #define AUDIT_AUX_IPCPERM	0
115 
116 struct audit_aux_data_mq_open {
117 	struct audit_aux_data	d;
118 	int			oflag;
119 	mode_t			mode;
120 	struct mq_attr		attr;
121 };
122 
123 struct audit_aux_data_mq_sendrecv {
124 	struct audit_aux_data	d;
125 	mqd_t			mqdes;
126 	size_t			msg_len;
127 	unsigned int		msg_prio;
128 	struct timespec		abs_timeout;
129 };
130 
131 struct audit_aux_data_mq_notify {
132 	struct audit_aux_data	d;
133 	mqd_t			mqdes;
134 	struct sigevent 	notification;
135 };
136 
137 struct audit_aux_data_mq_getsetattr {
138 	struct audit_aux_data	d;
139 	mqd_t			mqdes;
140 	struct mq_attr 		mqstat;
141 };
142 
143 struct audit_aux_data_ipcctl {
144 	struct audit_aux_data	d;
145 	struct ipc_perm		p;
146 	unsigned long		qbytes;
147 	uid_t			uid;
148 	gid_t			gid;
149 	mode_t			mode;
150 	u32			osid;
151 };
152 
153 struct audit_aux_data_execve {
154 	struct audit_aux_data	d;
155 	int argc;
156 	int envc;
157 	char mem[0];
158 };
159 
160 struct audit_aux_data_socketcall {
161 	struct audit_aux_data	d;
162 	int			nargs;
163 	unsigned long		args[0];
164 };
165 
166 struct audit_aux_data_sockaddr {
167 	struct audit_aux_data	d;
168 	int			len;
169 	char			a[0];
170 };
171 
172 struct audit_aux_data_path {
173 	struct audit_aux_data	d;
174 	struct dentry		*dentry;
175 	struct vfsmount		*mnt;
176 };
177 
178 /* The per-task audit context. */
179 struct audit_context {
180 	int		    dummy;	/* must be the first element */
181 	int		    in_syscall;	/* 1 if task is in a syscall */
182 	enum audit_state    state;
183 	unsigned int	    serial;     /* serial number for record */
184 	struct timespec	    ctime;      /* time of syscall entry */
185 	uid_t		    loginuid;   /* login uid (identity) */
186 	int		    major;      /* syscall number */
187 	unsigned long	    argv[4];    /* syscall arguments */
188 	int		    return_valid; /* return code is valid */
189 	long		    return_code;/* syscall return code */
190 	int		    auditable;  /* 1 if record should be written */
191 	int		    name_count;
192 	struct audit_names  names[AUDIT_NAMES];
193 	char *		    filterkey;	/* key for rule that triggered record */
194 	struct dentry *	    pwd;
195 	struct vfsmount *   pwdmnt;
196 	struct audit_context *previous; /* For nested syscalls */
197 	struct audit_aux_data *aux;
198 
199 				/* Save things to print about task_struct */
200 	pid_t		    pid, ppid;
201 	uid_t		    uid, euid, suid, fsuid;
202 	gid_t		    gid, egid, sgid, fsgid;
203 	unsigned long	    personality;
204 	int		    arch;
205 
206 #if AUDIT_DEBUG
207 	int		    put_count;
208 	int		    ino_count;
209 #endif
210 };
211 
212 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE])
213 static inline int open_arg(int flags, int mask)
214 {
215 	int n = ACC_MODE(flags);
216 	if (flags & (O_TRUNC | O_CREAT))
217 		n |= AUDIT_PERM_WRITE;
218 	return n & mask;
219 }
220 
221 static int audit_match_perm(struct audit_context *ctx, int mask)
222 {
223 	unsigned n = ctx->major;
224 	switch (audit_classify_syscall(ctx->arch, n)) {
225 	case 0:	/* native */
226 		if ((mask & AUDIT_PERM_WRITE) &&
227 		     audit_match_class(AUDIT_CLASS_WRITE, n))
228 			return 1;
229 		if ((mask & AUDIT_PERM_READ) &&
230 		     audit_match_class(AUDIT_CLASS_READ, n))
231 			return 1;
232 		if ((mask & AUDIT_PERM_ATTR) &&
233 		     audit_match_class(AUDIT_CLASS_CHATTR, n))
234 			return 1;
235 		return 0;
236 	case 1: /* 32bit on biarch */
237 		if ((mask & AUDIT_PERM_WRITE) &&
238 		     audit_match_class(AUDIT_CLASS_WRITE_32, n))
239 			return 1;
240 		if ((mask & AUDIT_PERM_READ) &&
241 		     audit_match_class(AUDIT_CLASS_READ_32, n))
242 			return 1;
243 		if ((mask & AUDIT_PERM_ATTR) &&
244 		     audit_match_class(AUDIT_CLASS_CHATTR_32, n))
245 			return 1;
246 		return 0;
247 	case 2: /* open */
248 		return mask & ACC_MODE(ctx->argv[1]);
249 	case 3: /* openat */
250 		return mask & ACC_MODE(ctx->argv[2]);
251 	case 4: /* socketcall */
252 		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
253 	case 5: /* execve */
254 		return mask & AUDIT_PERM_EXEC;
255 	default:
256 		return 0;
257 	}
258 }
259 
260 /* Determine if any context name data matches a rule's watch data */
261 /* Compare a task_struct with an audit_rule.  Return 1 on match, 0
262  * otherwise. */
263 static int audit_filter_rules(struct task_struct *tsk,
264 			      struct audit_krule *rule,
265 			      struct audit_context *ctx,
266 			      struct audit_names *name,
267 			      enum audit_state *state)
268 {
269 	int i, j, need_sid = 1;
270 	u32 sid;
271 
272 	for (i = 0; i < rule->field_count; i++) {
273 		struct audit_field *f = &rule->fields[i];
274 		int result = 0;
275 
276 		switch (f->type) {
277 		case AUDIT_PID:
278 			result = audit_comparator(tsk->pid, f->op, f->val);
279 			break;
280 		case AUDIT_PPID:
281 			if (ctx)
282 				result = audit_comparator(ctx->ppid, f->op, f->val);
283 			break;
284 		case AUDIT_UID:
285 			result = audit_comparator(tsk->uid, f->op, f->val);
286 			break;
287 		case AUDIT_EUID:
288 			result = audit_comparator(tsk->euid, f->op, f->val);
289 			break;
290 		case AUDIT_SUID:
291 			result = audit_comparator(tsk->suid, f->op, f->val);
292 			break;
293 		case AUDIT_FSUID:
294 			result = audit_comparator(tsk->fsuid, f->op, f->val);
295 			break;
296 		case AUDIT_GID:
297 			result = audit_comparator(tsk->gid, f->op, f->val);
298 			break;
299 		case AUDIT_EGID:
300 			result = audit_comparator(tsk->egid, f->op, f->val);
301 			break;
302 		case AUDIT_SGID:
303 			result = audit_comparator(tsk->sgid, f->op, f->val);
304 			break;
305 		case AUDIT_FSGID:
306 			result = audit_comparator(tsk->fsgid, f->op, f->val);
307 			break;
308 		case AUDIT_PERS:
309 			result = audit_comparator(tsk->personality, f->op, f->val);
310 			break;
311 		case AUDIT_ARCH:
312  			if (ctx)
313 				result = audit_comparator(ctx->arch, f->op, f->val);
314 			break;
315 
316 		case AUDIT_EXIT:
317 			if (ctx && ctx->return_valid)
318 				result = audit_comparator(ctx->return_code, f->op, f->val);
319 			break;
320 		case AUDIT_SUCCESS:
321 			if (ctx && ctx->return_valid) {
322 				if (f->val)
323 					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
324 				else
325 					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
326 			}
327 			break;
328 		case AUDIT_DEVMAJOR:
329 			if (name)
330 				result = audit_comparator(MAJOR(name->dev),
331 							  f->op, f->val);
332 			else if (ctx) {
333 				for (j = 0; j < ctx->name_count; j++) {
334 					if (audit_comparator(MAJOR(ctx->names[j].dev),	f->op, f->val)) {
335 						++result;
336 						break;
337 					}
338 				}
339 			}
340 			break;
341 		case AUDIT_DEVMINOR:
342 			if (name)
343 				result = audit_comparator(MINOR(name->dev),
344 							  f->op, f->val);
345 			else if (ctx) {
346 				for (j = 0; j < ctx->name_count; j++) {
347 					if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) {
348 						++result;
349 						break;
350 					}
351 				}
352 			}
353 			break;
354 		case AUDIT_INODE:
355 			if (name)
356 				result = (name->ino == f->val);
357 			else if (ctx) {
358 				for (j = 0; j < ctx->name_count; j++) {
359 					if (audit_comparator(ctx->names[j].ino, f->op, f->val)) {
360 						++result;
361 						break;
362 					}
363 				}
364 			}
365 			break;
366 		case AUDIT_WATCH:
367 			if (name && rule->watch->ino != (unsigned long)-1)
368 				result = (name->dev == rule->watch->dev &&
369 					  name->ino == rule->watch->ino);
370 			break;
371 		case AUDIT_LOGINUID:
372 			result = 0;
373 			if (ctx)
374 				result = audit_comparator(ctx->loginuid, f->op, f->val);
375 			break;
376 		case AUDIT_SUBJ_USER:
377 		case AUDIT_SUBJ_ROLE:
378 		case AUDIT_SUBJ_TYPE:
379 		case AUDIT_SUBJ_SEN:
380 		case AUDIT_SUBJ_CLR:
381 			/* NOTE: this may return negative values indicating
382 			   a temporary error.  We simply treat this as a
383 			   match for now to avoid losing information that
384 			   may be wanted.   An error message will also be
385 			   logged upon error */
386 			if (f->se_rule) {
387 				if (need_sid) {
388 					selinux_task_ctxid(tsk, &sid);
389 					need_sid = 0;
390 				}
391 				result = selinux_audit_rule_match(sid, f->type,
392 				                                  f->op,
393 				                                  f->se_rule,
394 				                                  ctx);
395 			}
396 			break;
397 		case AUDIT_OBJ_USER:
398 		case AUDIT_OBJ_ROLE:
399 		case AUDIT_OBJ_TYPE:
400 		case AUDIT_OBJ_LEV_LOW:
401 		case AUDIT_OBJ_LEV_HIGH:
402 			/* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
403 			   also applies here */
404 			if (f->se_rule) {
405 				/* Find files that match */
406 				if (name) {
407 					result = selinux_audit_rule_match(
408 					           name->osid, f->type, f->op,
409 					           f->se_rule, ctx);
410 				} else if (ctx) {
411 					for (j = 0; j < ctx->name_count; j++) {
412 						if (selinux_audit_rule_match(
413 						      ctx->names[j].osid,
414 						      f->type, f->op,
415 						      f->se_rule, ctx)) {
416 							++result;
417 							break;
418 						}
419 					}
420 				}
421 				/* Find ipc objects that match */
422 				if (ctx) {
423 					struct audit_aux_data *aux;
424 					for (aux = ctx->aux; aux;
425 					     aux = aux->next) {
426 						if (aux->type == AUDIT_IPC) {
427 							struct audit_aux_data_ipcctl *axi = (void *)aux;
428 							if (selinux_audit_rule_match(axi->osid, f->type, f->op, f->se_rule, ctx)) {
429 								++result;
430 								break;
431 							}
432 						}
433 					}
434 				}
435 			}
436 			break;
437 		case AUDIT_ARG0:
438 		case AUDIT_ARG1:
439 		case AUDIT_ARG2:
440 		case AUDIT_ARG3:
441 			if (ctx)
442 				result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
443 			break;
444 		case AUDIT_FILTERKEY:
445 			/* ignore this field for filtering */
446 			result = 1;
447 			break;
448 		case AUDIT_PERM:
449 			result = audit_match_perm(ctx, f->val);
450 			break;
451 		}
452 
453 		if (!result)
454 			return 0;
455 	}
456 	if (rule->filterkey)
457 		ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
458 	switch (rule->action) {
459 	case AUDIT_NEVER:    *state = AUDIT_DISABLED;	    break;
460 	case AUDIT_ALWAYS:   *state = AUDIT_RECORD_CONTEXT; break;
461 	}
462 	return 1;
463 }
464 
465 /* At process creation time, we can determine if system-call auditing is
466  * completely disabled for this task.  Since we only have the task
467  * structure at this point, we can only check uid and gid.
468  */
469 static enum audit_state audit_filter_task(struct task_struct *tsk)
470 {
471 	struct audit_entry *e;
472 	enum audit_state   state;
473 
474 	rcu_read_lock();
475 	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
476 		if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) {
477 			rcu_read_unlock();
478 			return state;
479 		}
480 	}
481 	rcu_read_unlock();
482 	return AUDIT_BUILD_CONTEXT;
483 }
484 
485 /* At syscall entry and exit time, this filter is called if the
486  * audit_state is not low enough that auditing cannot take place, but is
487  * also not high enough that we already know we have to write an audit
488  * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
489  */
490 static enum audit_state audit_filter_syscall(struct task_struct *tsk,
491 					     struct audit_context *ctx,
492 					     struct list_head *list)
493 {
494 	struct audit_entry *e;
495 	enum audit_state state;
496 
497 	if (audit_pid && tsk->tgid == audit_pid)
498 		return AUDIT_DISABLED;
499 
500 	rcu_read_lock();
501 	if (!list_empty(list)) {
502 		int word = AUDIT_WORD(ctx->major);
503 		int bit  = AUDIT_BIT(ctx->major);
504 
505 		list_for_each_entry_rcu(e, list, list) {
506 			if ((e->rule.mask[word] & bit) == bit &&
507 			    audit_filter_rules(tsk, &e->rule, ctx, NULL,
508 					       &state)) {
509 				rcu_read_unlock();
510 				return state;
511 			}
512 		}
513 	}
514 	rcu_read_unlock();
515 	return AUDIT_BUILD_CONTEXT;
516 }
517 
518 /* At syscall exit time, this filter is called if any audit_names[] have been
519  * collected during syscall processing.  We only check rules in sublists at hash
520  * buckets applicable to the inode numbers in audit_names[].
521  * Regarding audit_state, same rules apply as for audit_filter_syscall().
522  */
523 enum audit_state audit_filter_inodes(struct task_struct *tsk,
524 				     struct audit_context *ctx)
525 {
526 	int i;
527 	struct audit_entry *e;
528 	enum audit_state state;
529 
530 	if (audit_pid && tsk->tgid == audit_pid)
531 		return AUDIT_DISABLED;
532 
533 	rcu_read_lock();
534 	for (i = 0; i < ctx->name_count; i++) {
535 		int word = AUDIT_WORD(ctx->major);
536 		int bit  = AUDIT_BIT(ctx->major);
537 		struct audit_names *n = &ctx->names[i];
538 		int h = audit_hash_ino((u32)n->ino);
539 		struct list_head *list = &audit_inode_hash[h];
540 
541 		if (list_empty(list))
542 			continue;
543 
544 		list_for_each_entry_rcu(e, list, list) {
545 			if ((e->rule.mask[word] & bit) == bit &&
546 			    audit_filter_rules(tsk, &e->rule, ctx, n, &state)) {
547 				rcu_read_unlock();
548 				return state;
549 			}
550 		}
551 	}
552 	rcu_read_unlock();
553 	return AUDIT_BUILD_CONTEXT;
554 }
555 
556 void audit_set_auditable(struct audit_context *ctx)
557 {
558 	ctx->auditable = 1;
559 }
560 
561 static inline struct audit_context *audit_get_context(struct task_struct *tsk,
562 						      int return_valid,
563 						      int return_code)
564 {
565 	struct audit_context *context = tsk->audit_context;
566 
567 	if (likely(!context))
568 		return NULL;
569 	context->return_valid = return_valid;
570 	context->return_code  = return_code;
571 
572 	if (context->in_syscall && !context->dummy && !context->auditable) {
573 		enum audit_state state;
574 
575 		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
576 		if (state == AUDIT_RECORD_CONTEXT) {
577 			context->auditable = 1;
578 			goto get_context;
579 		}
580 
581 		state = audit_filter_inodes(tsk, context);
582 		if (state == AUDIT_RECORD_CONTEXT)
583 			context->auditable = 1;
584 
585 	}
586 
587 get_context:
588 
589 	tsk->audit_context = NULL;
590 	return context;
591 }
592 
593 static inline void audit_free_names(struct audit_context *context)
594 {
595 	int i;
596 
597 #if AUDIT_DEBUG == 2
598 	if (context->auditable
599 	    ||context->put_count + context->ino_count != context->name_count) {
600 		printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
601 		       " name_count=%d put_count=%d"
602 		       " ino_count=%d [NOT freeing]\n",
603 		       __FILE__, __LINE__,
604 		       context->serial, context->major, context->in_syscall,
605 		       context->name_count, context->put_count,
606 		       context->ino_count);
607 		for (i = 0; i < context->name_count; i++) {
608 			printk(KERN_ERR "names[%d] = %p = %s\n", i,
609 			       context->names[i].name,
610 			       context->names[i].name ?: "(null)");
611 		}
612 		dump_stack();
613 		return;
614 	}
615 #endif
616 #if AUDIT_DEBUG
617 	context->put_count  = 0;
618 	context->ino_count  = 0;
619 #endif
620 
621 	for (i = 0; i < context->name_count; i++) {
622 		if (context->names[i].name && context->names[i].name_put)
623 			__putname(context->names[i].name);
624 	}
625 	context->name_count = 0;
626 	if (context->pwd)
627 		dput(context->pwd);
628 	if (context->pwdmnt)
629 		mntput(context->pwdmnt);
630 	context->pwd = NULL;
631 	context->pwdmnt = NULL;
632 }
633 
634 static inline void audit_free_aux(struct audit_context *context)
635 {
636 	struct audit_aux_data *aux;
637 
638 	while ((aux = context->aux)) {
639 		if (aux->type == AUDIT_AVC_PATH) {
640 			struct audit_aux_data_path *axi = (void *)aux;
641 			dput(axi->dentry);
642 			mntput(axi->mnt);
643 		}
644 
645 		context->aux = aux->next;
646 		kfree(aux);
647 	}
648 }
649 
650 static inline void audit_zero_context(struct audit_context *context,
651 				      enum audit_state state)
652 {
653 	uid_t loginuid = context->loginuid;
654 
655 	memset(context, 0, sizeof(*context));
656 	context->state      = state;
657 	context->loginuid   = loginuid;
658 }
659 
660 static inline struct audit_context *audit_alloc_context(enum audit_state state)
661 {
662 	struct audit_context *context;
663 
664 	if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
665 		return NULL;
666 	audit_zero_context(context, state);
667 	return context;
668 }
669 
670 /**
671  * audit_alloc - allocate an audit context block for a task
672  * @tsk: task
673  *
674  * Filter on the task information and allocate a per-task audit context
675  * if necessary.  Doing so turns on system call auditing for the
676  * specified task.  This is called from copy_process, so no lock is
677  * needed.
678  */
679 int audit_alloc(struct task_struct *tsk)
680 {
681 	struct audit_context *context;
682 	enum audit_state     state;
683 
684 	if (likely(!audit_enabled))
685 		return 0; /* Return if not auditing. */
686 
687 	state = audit_filter_task(tsk);
688 	if (likely(state == AUDIT_DISABLED))
689 		return 0;
690 
691 	if (!(context = audit_alloc_context(state))) {
692 		audit_log_lost("out of memory in audit_alloc");
693 		return -ENOMEM;
694 	}
695 
696 				/* Preserve login uid */
697 	context->loginuid = -1;
698 	if (current->audit_context)
699 		context->loginuid = current->audit_context->loginuid;
700 
701 	tsk->audit_context  = context;
702 	set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
703 	return 0;
704 }
705 
706 static inline void audit_free_context(struct audit_context *context)
707 {
708 	struct audit_context *previous;
709 	int		     count = 0;
710 
711 	do {
712 		previous = context->previous;
713 		if (previous || (count &&  count < 10)) {
714 			++count;
715 			printk(KERN_ERR "audit(:%d): major=%d name_count=%d:"
716 			       " freeing multiple contexts (%d)\n",
717 			       context->serial, context->major,
718 			       context->name_count, count);
719 		}
720 		audit_free_names(context);
721 		audit_free_aux(context);
722 		kfree(context->filterkey);
723 		kfree(context);
724 		context  = previous;
725 	} while (context);
726 	if (count >= 10)
727 		printk(KERN_ERR "audit: freed %d contexts\n", count);
728 }
729 
730 static void audit_log_task_context(struct audit_buffer *ab)
731 {
732 	char *ctx = NULL;
733 	ssize_t len = 0;
734 
735 	len = security_getprocattr(current, "current", NULL, 0);
736 	if (len < 0) {
737 		if (len != -EINVAL)
738 			goto error_path;
739 		return;
740 	}
741 
742 	ctx = kmalloc(len, GFP_KERNEL);
743 	if (!ctx)
744 		goto error_path;
745 
746 	len = security_getprocattr(current, "current", ctx, len);
747 	if (len < 0 )
748 		goto error_path;
749 
750 	audit_log_format(ab, " subj=%s", ctx);
751 	return;
752 
753 error_path:
754 	kfree(ctx);
755 	audit_panic("error in audit_log_task_context");
756 	return;
757 }
758 
759 static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
760 {
761 	char name[sizeof(tsk->comm)];
762 	struct mm_struct *mm = tsk->mm;
763 	struct vm_area_struct *vma;
764 
765 	/* tsk == current */
766 
767 	get_task_comm(name, tsk);
768 	audit_log_format(ab, " comm=");
769 	audit_log_untrustedstring(ab, name);
770 
771 	if (mm) {
772 		down_read(&mm->mmap_sem);
773 		vma = mm->mmap;
774 		while (vma) {
775 			if ((vma->vm_flags & VM_EXECUTABLE) &&
776 			    vma->vm_file) {
777 				audit_log_d_path(ab, "exe=",
778 						 vma->vm_file->f_dentry,
779 						 vma->vm_file->f_vfsmnt);
780 				break;
781 			}
782 			vma = vma->vm_next;
783 		}
784 		up_read(&mm->mmap_sem);
785 	}
786 	audit_log_task_context(ab);
787 }
788 
789 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
790 {
791 	int i, call_panic = 0;
792 	struct audit_buffer *ab;
793 	struct audit_aux_data *aux;
794 	const char *tty;
795 
796 	/* tsk == current */
797 	context->pid = tsk->pid;
798 	context->ppid = sys_getppid();	/* sic.  tsk == current in all cases */
799 	context->uid = tsk->uid;
800 	context->gid = tsk->gid;
801 	context->euid = tsk->euid;
802 	context->suid = tsk->suid;
803 	context->fsuid = tsk->fsuid;
804 	context->egid = tsk->egid;
805 	context->sgid = tsk->sgid;
806 	context->fsgid = tsk->fsgid;
807 	context->personality = tsk->personality;
808 
809 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
810 	if (!ab)
811 		return;		/* audit_panic has been called */
812 	audit_log_format(ab, "arch=%x syscall=%d",
813 			 context->arch, context->major);
814 	if (context->personality != PER_LINUX)
815 		audit_log_format(ab, " per=%lx", context->personality);
816 	if (context->return_valid)
817 		audit_log_format(ab, " success=%s exit=%ld",
818 				 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
819 				 context->return_code);
820 	if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
821 		tty = tsk->signal->tty->name;
822 	else
823 		tty = "(none)";
824 	audit_log_format(ab,
825 		  " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
826 		  " ppid=%d pid=%d auid=%u uid=%u gid=%u"
827 		  " euid=%u suid=%u fsuid=%u"
828 		  " egid=%u sgid=%u fsgid=%u tty=%s",
829 		  context->argv[0],
830 		  context->argv[1],
831 		  context->argv[2],
832 		  context->argv[3],
833 		  context->name_count,
834 		  context->ppid,
835 		  context->pid,
836 		  context->loginuid,
837 		  context->uid,
838 		  context->gid,
839 		  context->euid, context->suid, context->fsuid,
840 		  context->egid, context->sgid, context->fsgid, tty);
841 	audit_log_task_info(ab, tsk);
842 	if (context->filterkey) {
843 		audit_log_format(ab, " key=");
844 		audit_log_untrustedstring(ab, context->filterkey);
845 	} else
846 		audit_log_format(ab, " key=(null)");
847 	audit_log_end(ab);
848 
849 	for (aux = context->aux; aux; aux = aux->next) {
850 
851 		ab = audit_log_start(context, GFP_KERNEL, aux->type);
852 		if (!ab)
853 			continue; /* audit_panic has been called */
854 
855 		switch (aux->type) {
856 		case AUDIT_MQ_OPEN: {
857 			struct audit_aux_data_mq_open *axi = (void *)aux;
858 			audit_log_format(ab,
859 				"oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld "
860 				"mq_msgsize=%ld mq_curmsgs=%ld",
861 				axi->oflag, axi->mode, axi->attr.mq_flags,
862 				axi->attr.mq_maxmsg, axi->attr.mq_msgsize,
863 				axi->attr.mq_curmsgs);
864 			break; }
865 
866 		case AUDIT_MQ_SENDRECV: {
867 			struct audit_aux_data_mq_sendrecv *axi = (void *)aux;
868 			audit_log_format(ab,
869 				"mqdes=%d msg_len=%zd msg_prio=%u "
870 				"abs_timeout_sec=%ld abs_timeout_nsec=%ld",
871 				axi->mqdes, axi->msg_len, axi->msg_prio,
872 				axi->abs_timeout.tv_sec, axi->abs_timeout.tv_nsec);
873 			break; }
874 
875 		case AUDIT_MQ_NOTIFY: {
876 			struct audit_aux_data_mq_notify *axi = (void *)aux;
877 			audit_log_format(ab,
878 				"mqdes=%d sigev_signo=%d",
879 				axi->mqdes,
880 				axi->notification.sigev_signo);
881 			break; }
882 
883 		case AUDIT_MQ_GETSETATTR: {
884 			struct audit_aux_data_mq_getsetattr *axi = (void *)aux;
885 			audit_log_format(ab,
886 				"mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
887 				"mq_curmsgs=%ld ",
888 				axi->mqdes,
889 				axi->mqstat.mq_flags, axi->mqstat.mq_maxmsg,
890 				axi->mqstat.mq_msgsize, axi->mqstat.mq_curmsgs);
891 			break; }
892 
893 		case AUDIT_IPC: {
894 			struct audit_aux_data_ipcctl *axi = (void *)aux;
895 			audit_log_format(ab,
896 				 "ouid=%u ogid=%u mode=%x",
897 				 axi->uid, axi->gid, axi->mode);
898 			if (axi->osid != 0) {
899 				char *ctx = NULL;
900 				u32 len;
901 				if (selinux_ctxid_to_string(
902 						axi->osid, &ctx, &len)) {
903 					audit_log_format(ab, " osid=%u",
904 							axi->osid);
905 					call_panic = 1;
906 				} else
907 					audit_log_format(ab, " obj=%s", ctx);
908 				kfree(ctx);
909 			}
910 			break; }
911 
912 		case AUDIT_IPC_SET_PERM: {
913 			struct audit_aux_data_ipcctl *axi = (void *)aux;
914 			audit_log_format(ab,
915 				"qbytes=%lx ouid=%u ogid=%u mode=%x",
916 				axi->qbytes, axi->uid, axi->gid, axi->mode);
917 			break; }
918 
919 		case AUDIT_EXECVE: {
920 			struct audit_aux_data_execve *axi = (void *)aux;
921 			int i;
922 			const char *p;
923 			for (i = 0, p = axi->mem; i < axi->argc; i++) {
924 				audit_log_format(ab, "a%d=", i);
925 				p = audit_log_untrustedstring(ab, p);
926 				audit_log_format(ab, "\n");
927 			}
928 			break; }
929 
930 		case AUDIT_SOCKETCALL: {
931 			int i;
932 			struct audit_aux_data_socketcall *axs = (void *)aux;
933 			audit_log_format(ab, "nargs=%d", axs->nargs);
934 			for (i=0; i<axs->nargs; i++)
935 				audit_log_format(ab, " a%d=%lx", i, axs->args[i]);
936 			break; }
937 
938 		case AUDIT_SOCKADDR: {
939 			struct audit_aux_data_sockaddr *axs = (void *)aux;
940 
941 			audit_log_format(ab, "saddr=");
942 			audit_log_hex(ab, axs->a, axs->len);
943 			break; }
944 
945 		case AUDIT_AVC_PATH: {
946 			struct audit_aux_data_path *axi = (void *)aux;
947 			audit_log_d_path(ab, "path=", axi->dentry, axi->mnt);
948 			break; }
949 
950 		}
951 		audit_log_end(ab);
952 	}
953 
954 	if (context->pwd && context->pwdmnt) {
955 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
956 		if (ab) {
957 			audit_log_d_path(ab, "cwd=", context->pwd, context->pwdmnt);
958 			audit_log_end(ab);
959 		}
960 	}
961 	for (i = 0; i < context->name_count; i++) {
962 		struct audit_names *n = &context->names[i];
963 
964 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
965 		if (!ab)
966 			continue; /* audit_panic has been called */
967 
968 		audit_log_format(ab, "item=%d", i);
969 
970 		if (n->name) {
971 			switch(n->name_len) {
972 			case AUDIT_NAME_FULL:
973 				/* log the full path */
974 				audit_log_format(ab, " name=");
975 				audit_log_untrustedstring(ab, n->name);
976 				break;
977 			case 0:
978 				/* name was specified as a relative path and the
979 				 * directory component is the cwd */
980 				audit_log_d_path(ab, " name=", context->pwd,
981 						 context->pwdmnt);
982 				break;
983 			default:
984 				/* log the name's directory component */
985 				audit_log_format(ab, " name=");
986 				audit_log_n_untrustedstring(ab, n->name_len,
987 							    n->name);
988 			}
989 		} else
990 			audit_log_format(ab, " name=(null)");
991 
992 		if (n->ino != (unsigned long)-1) {
993 			audit_log_format(ab, " inode=%lu"
994 					 " dev=%02x:%02x mode=%#o"
995 					 " ouid=%u ogid=%u rdev=%02x:%02x",
996 					 n->ino,
997 					 MAJOR(n->dev),
998 					 MINOR(n->dev),
999 					 n->mode,
1000 					 n->uid,
1001 					 n->gid,
1002 					 MAJOR(n->rdev),
1003 					 MINOR(n->rdev));
1004 		}
1005 		if (n->osid != 0) {
1006 			char *ctx = NULL;
1007 			u32 len;
1008 			if (selinux_ctxid_to_string(
1009 				n->osid, &ctx, &len)) {
1010 				audit_log_format(ab, " osid=%u", n->osid);
1011 				call_panic = 2;
1012 			} else
1013 				audit_log_format(ab, " obj=%s", ctx);
1014 			kfree(ctx);
1015 		}
1016 
1017 		audit_log_end(ab);
1018 	}
1019 	if (call_panic)
1020 		audit_panic("error converting sid to string");
1021 }
1022 
1023 /**
1024  * audit_free - free a per-task audit context
1025  * @tsk: task whose audit context block to free
1026  *
1027  * Called from copy_process and do_exit
1028  */
1029 void audit_free(struct task_struct *tsk)
1030 {
1031 	struct audit_context *context;
1032 
1033 	context = audit_get_context(tsk, 0, 0);
1034 	if (likely(!context))
1035 		return;
1036 
1037 	/* Check for system calls that do not go through the exit
1038 	 * function (e.g., exit_group), then free context block.
1039 	 * We use GFP_ATOMIC here because we might be doing this
1040 	 * in the context of the idle thread */
1041 	/* that can happen only if we are called from do_exit() */
1042 	if (context->in_syscall && context->auditable)
1043 		audit_log_exit(context, tsk);
1044 
1045 	audit_free_context(context);
1046 }
1047 
1048 /**
1049  * audit_syscall_entry - fill in an audit record at syscall entry
1050  * @tsk: task being audited
1051  * @arch: architecture type
1052  * @major: major syscall type (function)
1053  * @a1: additional syscall register 1
1054  * @a2: additional syscall register 2
1055  * @a3: additional syscall register 3
1056  * @a4: additional syscall register 4
1057  *
1058  * Fill in audit context at syscall entry.  This only happens if the
1059  * audit context was created when the task was created and the state or
1060  * filters demand the audit context be built.  If the state from the
1061  * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1062  * then the record will be written at syscall exit time (otherwise, it
1063  * will only be written if another part of the kernel requests that it
1064  * be written).
1065  */
1066 void audit_syscall_entry(int arch, int major,
1067 			 unsigned long a1, unsigned long a2,
1068 			 unsigned long a3, unsigned long a4)
1069 {
1070 	struct task_struct *tsk = current;
1071 	struct audit_context *context = tsk->audit_context;
1072 	enum audit_state     state;
1073 
1074 	BUG_ON(!context);
1075 
1076 	/*
1077 	 * This happens only on certain architectures that make system
1078 	 * calls in kernel_thread via the entry.S interface, instead of
1079 	 * with direct calls.  (If you are porting to a new
1080 	 * architecture, hitting this condition can indicate that you
1081 	 * got the _exit/_leave calls backward in entry.S.)
1082 	 *
1083 	 * i386     no
1084 	 * x86_64   no
1085 	 * ppc64    yes (see arch/powerpc/platforms/iseries/misc.S)
1086 	 *
1087 	 * This also happens with vm86 emulation in a non-nested manner
1088 	 * (entries without exits), so this case must be caught.
1089 	 */
1090 	if (context->in_syscall) {
1091 		struct audit_context *newctx;
1092 
1093 #if AUDIT_DEBUG
1094 		printk(KERN_ERR
1095 		       "audit(:%d) pid=%d in syscall=%d;"
1096 		       " entering syscall=%d\n",
1097 		       context->serial, tsk->pid, context->major, major);
1098 #endif
1099 		newctx = audit_alloc_context(context->state);
1100 		if (newctx) {
1101 			newctx->previous   = context;
1102 			context		   = newctx;
1103 			tsk->audit_context = newctx;
1104 		} else	{
1105 			/* If we can't alloc a new context, the best we
1106 			 * can do is to leak memory (any pending putname
1107 			 * will be lost).  The only other alternative is
1108 			 * to abandon auditing. */
1109 			audit_zero_context(context, context->state);
1110 		}
1111 	}
1112 	BUG_ON(context->in_syscall || context->name_count);
1113 
1114 	if (!audit_enabled)
1115 		return;
1116 
1117 	context->arch	    = arch;
1118 	context->major      = major;
1119 	context->argv[0]    = a1;
1120 	context->argv[1]    = a2;
1121 	context->argv[2]    = a3;
1122 	context->argv[3]    = a4;
1123 
1124 	state = context->state;
1125 	context->dummy = !audit_n_rules;
1126 	if (!context->dummy && (state == AUDIT_SETUP_CONTEXT || state == AUDIT_BUILD_CONTEXT))
1127 		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1128 	if (likely(state == AUDIT_DISABLED))
1129 		return;
1130 
1131 	context->serial     = 0;
1132 	context->ctime      = CURRENT_TIME;
1133 	context->in_syscall = 1;
1134 	context->auditable  = !!(state == AUDIT_RECORD_CONTEXT);
1135 }
1136 
1137 /**
1138  * audit_syscall_exit - deallocate audit context after a system call
1139  * @tsk: task being audited
1140  * @valid: success/failure flag
1141  * @return_code: syscall return value
1142  *
1143  * Tear down after system call.  If the audit context has been marked as
1144  * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1145  * filtering, or because some other part of the kernel write an audit
1146  * message), then write out the syscall information.  In call cases,
1147  * free the names stored from getname().
1148  */
1149 void audit_syscall_exit(int valid, long return_code)
1150 {
1151 	struct task_struct *tsk = current;
1152 	struct audit_context *context;
1153 
1154 	context = audit_get_context(tsk, valid, return_code);
1155 
1156 	if (likely(!context))
1157 		return;
1158 
1159 	if (context->in_syscall && context->auditable)
1160 		audit_log_exit(context, tsk);
1161 
1162 	context->in_syscall = 0;
1163 	context->auditable  = 0;
1164 
1165 	if (context->previous) {
1166 		struct audit_context *new_context = context->previous;
1167 		context->previous  = NULL;
1168 		audit_free_context(context);
1169 		tsk->audit_context = new_context;
1170 	} else {
1171 		audit_free_names(context);
1172 		audit_free_aux(context);
1173 		kfree(context->filterkey);
1174 		context->filterkey = NULL;
1175 		tsk->audit_context = context;
1176 	}
1177 }
1178 
1179 /**
1180  * audit_getname - add a name to the list
1181  * @name: name to add
1182  *
1183  * Add a name to the list of audit names for this context.
1184  * Called from fs/namei.c:getname().
1185  */
1186 void __audit_getname(const char *name)
1187 {
1188 	struct audit_context *context = current->audit_context;
1189 
1190 	if (IS_ERR(name) || !name)
1191 		return;
1192 
1193 	if (!context->in_syscall) {
1194 #if AUDIT_DEBUG == 2
1195 		printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
1196 		       __FILE__, __LINE__, context->serial, name);
1197 		dump_stack();
1198 #endif
1199 		return;
1200 	}
1201 	BUG_ON(context->name_count >= AUDIT_NAMES);
1202 	context->names[context->name_count].name = name;
1203 	context->names[context->name_count].name_len = AUDIT_NAME_FULL;
1204 	context->names[context->name_count].name_put = 1;
1205 	context->names[context->name_count].ino  = (unsigned long)-1;
1206 	++context->name_count;
1207 	if (!context->pwd) {
1208 		read_lock(&current->fs->lock);
1209 		context->pwd = dget(current->fs->pwd);
1210 		context->pwdmnt = mntget(current->fs->pwdmnt);
1211 		read_unlock(&current->fs->lock);
1212 	}
1213 
1214 }
1215 
1216 /* audit_putname - intercept a putname request
1217  * @name: name to intercept and delay for putname
1218  *
1219  * If we have stored the name from getname in the audit context,
1220  * then we delay the putname until syscall exit.
1221  * Called from include/linux/fs.h:putname().
1222  */
1223 void audit_putname(const char *name)
1224 {
1225 	struct audit_context *context = current->audit_context;
1226 
1227 	BUG_ON(!context);
1228 	if (!context->in_syscall) {
1229 #if AUDIT_DEBUG == 2
1230 		printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n",
1231 		       __FILE__, __LINE__, context->serial, name);
1232 		if (context->name_count) {
1233 			int i;
1234 			for (i = 0; i < context->name_count; i++)
1235 				printk(KERN_ERR "name[%d] = %p = %s\n", i,
1236 				       context->names[i].name,
1237 				       context->names[i].name ?: "(null)");
1238 		}
1239 #endif
1240 		__putname(name);
1241 	}
1242 #if AUDIT_DEBUG
1243 	else {
1244 		++context->put_count;
1245 		if (context->put_count > context->name_count) {
1246 			printk(KERN_ERR "%s:%d(:%d): major=%d"
1247 			       " in_syscall=%d putname(%p) name_count=%d"
1248 			       " put_count=%d\n",
1249 			       __FILE__, __LINE__,
1250 			       context->serial, context->major,
1251 			       context->in_syscall, name, context->name_count,
1252 			       context->put_count);
1253 			dump_stack();
1254 		}
1255 	}
1256 #endif
1257 }
1258 
1259 /* Copy inode data into an audit_names. */
1260 static void audit_copy_inode(struct audit_names *name, const struct inode *inode)
1261 {
1262 	name->ino   = inode->i_ino;
1263 	name->dev   = inode->i_sb->s_dev;
1264 	name->mode  = inode->i_mode;
1265 	name->uid   = inode->i_uid;
1266 	name->gid   = inode->i_gid;
1267 	name->rdev  = inode->i_rdev;
1268 	selinux_get_inode_sid(inode, &name->osid);
1269 }
1270 
1271 /**
1272  * audit_inode - store the inode and device from a lookup
1273  * @name: name being audited
1274  * @inode: inode being audited
1275  *
1276  * Called from fs/namei.c:path_lookup().
1277  */
1278 void __audit_inode(const char *name, const struct inode *inode)
1279 {
1280 	int idx;
1281 	struct audit_context *context = current->audit_context;
1282 
1283 	if (!context->in_syscall)
1284 		return;
1285 	if (context->name_count
1286 	    && context->names[context->name_count-1].name
1287 	    && context->names[context->name_count-1].name == name)
1288 		idx = context->name_count - 1;
1289 	else if (context->name_count > 1
1290 		 && context->names[context->name_count-2].name
1291 		 && context->names[context->name_count-2].name == name)
1292 		idx = context->name_count - 2;
1293 	else {
1294 		/* FIXME: how much do we care about inodes that have no
1295 		 * associated name? */
1296 		if (context->name_count >= AUDIT_NAMES - AUDIT_NAMES_RESERVED)
1297 			return;
1298 		idx = context->name_count++;
1299 		context->names[idx].name = NULL;
1300 #if AUDIT_DEBUG
1301 		++context->ino_count;
1302 #endif
1303 	}
1304 	audit_copy_inode(&context->names[idx], inode);
1305 }
1306 
1307 /**
1308  * audit_inode_child - collect inode info for created/removed objects
1309  * @dname: inode's dentry name
1310  * @inode: inode being audited
1311  * @parent: inode of dentry parent
1312  *
1313  * For syscalls that create or remove filesystem objects, audit_inode
1314  * can only collect information for the filesystem object's parent.
1315  * This call updates the audit context with the child's information.
1316  * Syscalls that create a new filesystem object must be hooked after
1317  * the object is created.  Syscalls that remove a filesystem object
1318  * must be hooked prior, in order to capture the target inode during
1319  * unsuccessful attempts.
1320  */
1321 void __audit_inode_child(const char *dname, const struct inode *inode,
1322 			 const struct inode *parent)
1323 {
1324 	int idx;
1325 	struct audit_context *context = current->audit_context;
1326 	const char *found_name = NULL;
1327 	int dirlen = 0;
1328 
1329 	if (!context->in_syscall)
1330 		return;
1331 
1332 	/* determine matching parent */
1333 	if (!dname)
1334 		goto update_context;
1335 	for (idx = 0; idx < context->name_count; idx++)
1336 		if (context->names[idx].ino == parent->i_ino) {
1337 			const char *name = context->names[idx].name;
1338 
1339 			if (!name)
1340 				continue;
1341 
1342 			if (audit_compare_dname_path(dname, name, &dirlen) == 0) {
1343 				context->names[idx].name_len = dirlen;
1344 				found_name = name;
1345 				break;
1346 			}
1347 		}
1348 
1349 update_context:
1350 	idx = context->name_count++;
1351 #if AUDIT_DEBUG
1352 	context->ino_count++;
1353 #endif
1354 	/* Re-use the name belonging to the slot for a matching parent directory.
1355 	 * All names for this context are relinquished in audit_free_names() */
1356 	context->names[idx].name = found_name;
1357 	context->names[idx].name_len = AUDIT_NAME_FULL;
1358 	context->names[idx].name_put = 0;	/* don't call __putname() */
1359 
1360 	if (!inode)
1361 		context->names[idx].ino = (unsigned long)-1;
1362 	else
1363 		audit_copy_inode(&context->names[idx], inode);
1364 
1365 	/* A parent was not found in audit_names, so copy the inode data for the
1366 	 * provided parent. */
1367 	if (!found_name) {
1368 		idx = context->name_count++;
1369 #if AUDIT_DEBUG
1370 		context->ino_count++;
1371 #endif
1372 		audit_copy_inode(&context->names[idx], parent);
1373 	}
1374 }
1375 
1376 /**
1377  * audit_inode_update - update inode info for last collected name
1378  * @inode: inode being audited
1379  *
1380  * When open() is called on an existing object with the O_CREAT flag, the inode
1381  * data audit initially collects is incorrect.  This additional hook ensures
1382  * audit has the inode data for the actual object to be opened.
1383  */
1384 void __audit_inode_update(const struct inode *inode)
1385 {
1386 	struct audit_context *context = current->audit_context;
1387 	int idx;
1388 
1389 	if (!context->in_syscall || !inode)
1390 		return;
1391 
1392 	if (context->name_count == 0) {
1393 		context->name_count++;
1394 #if AUDIT_DEBUG
1395 		context->ino_count++;
1396 #endif
1397 	}
1398 	idx = context->name_count - 1;
1399 
1400 	audit_copy_inode(&context->names[idx], inode);
1401 }
1402 
1403 /**
1404  * auditsc_get_stamp - get local copies of audit_context values
1405  * @ctx: audit_context for the task
1406  * @t: timespec to store time recorded in the audit_context
1407  * @serial: serial value that is recorded in the audit_context
1408  *
1409  * Also sets the context as auditable.
1410  */
1411 void auditsc_get_stamp(struct audit_context *ctx,
1412 		       struct timespec *t, unsigned int *serial)
1413 {
1414 	if (!ctx->serial)
1415 		ctx->serial = audit_serial();
1416 	t->tv_sec  = ctx->ctime.tv_sec;
1417 	t->tv_nsec = ctx->ctime.tv_nsec;
1418 	*serial    = ctx->serial;
1419 	ctx->auditable = 1;
1420 }
1421 
1422 /**
1423  * audit_set_loginuid - set a task's audit_context loginuid
1424  * @task: task whose audit context is being modified
1425  * @loginuid: loginuid value
1426  *
1427  * Returns 0.
1428  *
1429  * Called (set) from fs/proc/base.c::proc_loginuid_write().
1430  */
1431 int audit_set_loginuid(struct task_struct *task, uid_t loginuid)
1432 {
1433 	struct audit_context *context = task->audit_context;
1434 
1435 	if (context) {
1436 		/* Only log if audit is enabled */
1437 		if (context->in_syscall) {
1438 			struct audit_buffer *ab;
1439 
1440 			ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
1441 			if (ab) {
1442 				audit_log_format(ab, "login pid=%d uid=%u "
1443 					"old auid=%u new auid=%u",
1444 					task->pid, task->uid,
1445 					context->loginuid, loginuid);
1446 				audit_log_end(ab);
1447 			}
1448 		}
1449 		context->loginuid = loginuid;
1450 	}
1451 	return 0;
1452 }
1453 
1454 /**
1455  * audit_get_loginuid - get the loginuid for an audit_context
1456  * @ctx: the audit_context
1457  *
1458  * Returns the context's loginuid or -1 if @ctx is NULL.
1459  */
1460 uid_t audit_get_loginuid(struct audit_context *ctx)
1461 {
1462 	return ctx ? ctx->loginuid : -1;
1463 }
1464 
1465 /**
1466  * __audit_mq_open - record audit data for a POSIX MQ open
1467  * @oflag: open flag
1468  * @mode: mode bits
1469  * @u_attr: queue attributes
1470  *
1471  * Returns 0 for success or NULL context or < 0 on error.
1472  */
1473 int __audit_mq_open(int oflag, mode_t mode, struct mq_attr __user *u_attr)
1474 {
1475 	struct audit_aux_data_mq_open *ax;
1476 	struct audit_context *context = current->audit_context;
1477 
1478 	if (!audit_enabled)
1479 		return 0;
1480 
1481 	if (likely(!context))
1482 		return 0;
1483 
1484 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1485 	if (!ax)
1486 		return -ENOMEM;
1487 
1488 	if (u_attr != NULL) {
1489 		if (copy_from_user(&ax->attr, u_attr, sizeof(ax->attr))) {
1490 			kfree(ax);
1491 			return -EFAULT;
1492 		}
1493 	} else
1494 		memset(&ax->attr, 0, sizeof(ax->attr));
1495 
1496 	ax->oflag = oflag;
1497 	ax->mode = mode;
1498 
1499 	ax->d.type = AUDIT_MQ_OPEN;
1500 	ax->d.next = context->aux;
1501 	context->aux = (void *)ax;
1502 	return 0;
1503 }
1504 
1505 /**
1506  * __audit_mq_timedsend - record audit data for a POSIX MQ timed send
1507  * @mqdes: MQ descriptor
1508  * @msg_len: Message length
1509  * @msg_prio: Message priority
1510  * @u_abs_timeout: Message timeout in absolute time
1511  *
1512  * Returns 0 for success or NULL context or < 0 on error.
1513  */
1514 int __audit_mq_timedsend(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
1515 			const struct timespec __user *u_abs_timeout)
1516 {
1517 	struct audit_aux_data_mq_sendrecv *ax;
1518 	struct audit_context *context = current->audit_context;
1519 
1520 	if (!audit_enabled)
1521 		return 0;
1522 
1523 	if (likely(!context))
1524 		return 0;
1525 
1526 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1527 	if (!ax)
1528 		return -ENOMEM;
1529 
1530 	if (u_abs_timeout != NULL) {
1531 		if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) {
1532 			kfree(ax);
1533 			return -EFAULT;
1534 		}
1535 	} else
1536 		memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout));
1537 
1538 	ax->mqdes = mqdes;
1539 	ax->msg_len = msg_len;
1540 	ax->msg_prio = msg_prio;
1541 
1542 	ax->d.type = AUDIT_MQ_SENDRECV;
1543 	ax->d.next = context->aux;
1544 	context->aux = (void *)ax;
1545 	return 0;
1546 }
1547 
1548 /**
1549  * __audit_mq_timedreceive - record audit data for a POSIX MQ timed receive
1550  * @mqdes: MQ descriptor
1551  * @msg_len: Message length
1552  * @u_msg_prio: Message priority
1553  * @u_abs_timeout: Message timeout in absolute time
1554  *
1555  * Returns 0 for success or NULL context or < 0 on error.
1556  */
1557 int __audit_mq_timedreceive(mqd_t mqdes, size_t msg_len,
1558 				unsigned int __user *u_msg_prio,
1559 				const struct timespec __user *u_abs_timeout)
1560 {
1561 	struct audit_aux_data_mq_sendrecv *ax;
1562 	struct audit_context *context = current->audit_context;
1563 
1564 	if (!audit_enabled)
1565 		return 0;
1566 
1567 	if (likely(!context))
1568 		return 0;
1569 
1570 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1571 	if (!ax)
1572 		return -ENOMEM;
1573 
1574 	if (u_msg_prio != NULL) {
1575 		if (get_user(ax->msg_prio, u_msg_prio)) {
1576 			kfree(ax);
1577 			return -EFAULT;
1578 		}
1579 	} else
1580 		ax->msg_prio = 0;
1581 
1582 	if (u_abs_timeout != NULL) {
1583 		if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) {
1584 			kfree(ax);
1585 			return -EFAULT;
1586 		}
1587 	} else
1588 		memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout));
1589 
1590 	ax->mqdes = mqdes;
1591 	ax->msg_len = msg_len;
1592 
1593 	ax->d.type = AUDIT_MQ_SENDRECV;
1594 	ax->d.next = context->aux;
1595 	context->aux = (void *)ax;
1596 	return 0;
1597 }
1598 
1599 /**
1600  * __audit_mq_notify - record audit data for a POSIX MQ notify
1601  * @mqdes: MQ descriptor
1602  * @u_notification: Notification event
1603  *
1604  * Returns 0 for success or NULL context or < 0 on error.
1605  */
1606 
1607 int __audit_mq_notify(mqd_t mqdes, const struct sigevent __user *u_notification)
1608 {
1609 	struct audit_aux_data_mq_notify *ax;
1610 	struct audit_context *context = current->audit_context;
1611 
1612 	if (!audit_enabled)
1613 		return 0;
1614 
1615 	if (likely(!context))
1616 		return 0;
1617 
1618 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1619 	if (!ax)
1620 		return -ENOMEM;
1621 
1622 	if (u_notification != NULL) {
1623 		if (copy_from_user(&ax->notification, u_notification, sizeof(ax->notification))) {
1624 			kfree(ax);
1625 			return -EFAULT;
1626 		}
1627 	} else
1628 		memset(&ax->notification, 0, sizeof(ax->notification));
1629 
1630 	ax->mqdes = mqdes;
1631 
1632 	ax->d.type = AUDIT_MQ_NOTIFY;
1633 	ax->d.next = context->aux;
1634 	context->aux = (void *)ax;
1635 	return 0;
1636 }
1637 
1638 /**
1639  * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
1640  * @mqdes: MQ descriptor
1641  * @mqstat: MQ flags
1642  *
1643  * Returns 0 for success or NULL context or < 0 on error.
1644  */
1645 int __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
1646 {
1647 	struct audit_aux_data_mq_getsetattr *ax;
1648 	struct audit_context *context = current->audit_context;
1649 
1650 	if (!audit_enabled)
1651 		return 0;
1652 
1653 	if (likely(!context))
1654 		return 0;
1655 
1656 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1657 	if (!ax)
1658 		return -ENOMEM;
1659 
1660 	ax->mqdes = mqdes;
1661 	ax->mqstat = *mqstat;
1662 
1663 	ax->d.type = AUDIT_MQ_GETSETATTR;
1664 	ax->d.next = context->aux;
1665 	context->aux = (void *)ax;
1666 	return 0;
1667 }
1668 
1669 /**
1670  * audit_ipc_obj - record audit data for ipc object
1671  * @ipcp: ipc permissions
1672  *
1673  * Returns 0 for success or NULL context or < 0 on error.
1674  */
1675 int __audit_ipc_obj(struct kern_ipc_perm *ipcp)
1676 {
1677 	struct audit_aux_data_ipcctl *ax;
1678 	struct audit_context *context = current->audit_context;
1679 
1680 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1681 	if (!ax)
1682 		return -ENOMEM;
1683 
1684 	ax->uid = ipcp->uid;
1685 	ax->gid = ipcp->gid;
1686 	ax->mode = ipcp->mode;
1687 	selinux_get_ipc_sid(ipcp, &ax->osid);
1688 
1689 	ax->d.type = AUDIT_IPC;
1690 	ax->d.next = context->aux;
1691 	context->aux = (void *)ax;
1692 	return 0;
1693 }
1694 
1695 /**
1696  * audit_ipc_set_perm - record audit data for new ipc permissions
1697  * @qbytes: msgq bytes
1698  * @uid: msgq user id
1699  * @gid: msgq group id
1700  * @mode: msgq mode (permissions)
1701  *
1702  * Returns 0 for success or NULL context or < 0 on error.
1703  */
1704 int __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode)
1705 {
1706 	struct audit_aux_data_ipcctl *ax;
1707 	struct audit_context *context = current->audit_context;
1708 
1709 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1710 	if (!ax)
1711 		return -ENOMEM;
1712 
1713 	ax->qbytes = qbytes;
1714 	ax->uid = uid;
1715 	ax->gid = gid;
1716 	ax->mode = mode;
1717 
1718 	ax->d.type = AUDIT_IPC_SET_PERM;
1719 	ax->d.next = context->aux;
1720 	context->aux = (void *)ax;
1721 	return 0;
1722 }
1723 
1724 int audit_bprm(struct linux_binprm *bprm)
1725 {
1726 	struct audit_aux_data_execve *ax;
1727 	struct audit_context *context = current->audit_context;
1728 	unsigned long p, next;
1729 	void *to;
1730 
1731 	if (likely(!audit_enabled || !context || context->dummy))
1732 		return 0;
1733 
1734 	ax = kmalloc(sizeof(*ax) + PAGE_SIZE * MAX_ARG_PAGES - bprm->p,
1735 				GFP_KERNEL);
1736 	if (!ax)
1737 		return -ENOMEM;
1738 
1739 	ax->argc = bprm->argc;
1740 	ax->envc = bprm->envc;
1741 	for (p = bprm->p, to = ax->mem; p < MAX_ARG_PAGES*PAGE_SIZE; p = next) {
1742 		struct page *page = bprm->page[p / PAGE_SIZE];
1743 		void *kaddr = kmap(page);
1744 		next = (p + PAGE_SIZE) & ~(PAGE_SIZE - 1);
1745 		memcpy(to, kaddr + (p & (PAGE_SIZE - 1)), next - p);
1746 		to += next - p;
1747 		kunmap(page);
1748 	}
1749 
1750 	ax->d.type = AUDIT_EXECVE;
1751 	ax->d.next = context->aux;
1752 	context->aux = (void *)ax;
1753 	return 0;
1754 }
1755 
1756 
1757 /**
1758  * audit_socketcall - record audit data for sys_socketcall
1759  * @nargs: number of args
1760  * @args: args array
1761  *
1762  * Returns 0 for success or NULL context or < 0 on error.
1763  */
1764 int audit_socketcall(int nargs, unsigned long *args)
1765 {
1766 	struct audit_aux_data_socketcall *ax;
1767 	struct audit_context *context = current->audit_context;
1768 
1769 	if (likely(!context || context->dummy))
1770 		return 0;
1771 
1772 	ax = kmalloc(sizeof(*ax) + nargs * sizeof(unsigned long), GFP_KERNEL);
1773 	if (!ax)
1774 		return -ENOMEM;
1775 
1776 	ax->nargs = nargs;
1777 	memcpy(ax->args, args, nargs * sizeof(unsigned long));
1778 
1779 	ax->d.type = AUDIT_SOCKETCALL;
1780 	ax->d.next = context->aux;
1781 	context->aux = (void *)ax;
1782 	return 0;
1783 }
1784 
1785 /**
1786  * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
1787  * @len: data length in user space
1788  * @a: data address in kernel space
1789  *
1790  * Returns 0 for success or NULL context or < 0 on error.
1791  */
1792 int audit_sockaddr(int len, void *a)
1793 {
1794 	struct audit_aux_data_sockaddr *ax;
1795 	struct audit_context *context = current->audit_context;
1796 
1797 	if (likely(!context || context->dummy))
1798 		return 0;
1799 
1800 	ax = kmalloc(sizeof(*ax) + len, GFP_KERNEL);
1801 	if (!ax)
1802 		return -ENOMEM;
1803 
1804 	ax->len = len;
1805 	memcpy(ax->a, a, len);
1806 
1807 	ax->d.type = AUDIT_SOCKADDR;
1808 	ax->d.next = context->aux;
1809 	context->aux = (void *)ax;
1810 	return 0;
1811 }
1812 
1813 /**
1814  * audit_avc_path - record the granting or denial of permissions
1815  * @dentry: dentry to record
1816  * @mnt: mnt to record
1817  *
1818  * Returns 0 for success or NULL context or < 0 on error.
1819  *
1820  * Called from security/selinux/avc.c::avc_audit()
1821  */
1822 int audit_avc_path(struct dentry *dentry, struct vfsmount *mnt)
1823 {
1824 	struct audit_aux_data_path *ax;
1825 	struct audit_context *context = current->audit_context;
1826 
1827 	if (likely(!context))
1828 		return 0;
1829 
1830 	ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
1831 	if (!ax)
1832 		return -ENOMEM;
1833 
1834 	ax->dentry = dget(dentry);
1835 	ax->mnt = mntget(mnt);
1836 
1837 	ax->d.type = AUDIT_AVC_PATH;
1838 	ax->d.next = context->aux;
1839 	context->aux = (void *)ax;
1840 	return 0;
1841 }
1842 
1843 /**
1844  * audit_signal_info - record signal info for shutting down audit subsystem
1845  * @sig: signal value
1846  * @t: task being signaled
1847  *
1848  * If the audit subsystem is being terminated, record the task (pid)
1849  * and uid that is doing that.
1850  */
1851 void __audit_signal_info(int sig, struct task_struct *t)
1852 {
1853 	extern pid_t audit_sig_pid;
1854 	extern uid_t audit_sig_uid;
1855 	extern u32 audit_sig_sid;
1856 
1857 	if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1) {
1858 		struct task_struct *tsk = current;
1859 		struct audit_context *ctx = tsk->audit_context;
1860 		audit_sig_pid = tsk->pid;
1861 		if (ctx)
1862 			audit_sig_uid = ctx->loginuid;
1863 		else
1864 			audit_sig_uid = tsk->uid;
1865 		selinux_get_task_sid(tsk, &audit_sig_sid);
1866 	}
1867 }
1868