xref: /openbmc/linux/kernel/auditsc.c (revision ca79522c)
1 /* auditsc.c -- System-call auditing support
2  * Handles all system-call specific auditing features.
3  *
4  * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
5  * Copyright 2005 Hewlett-Packard Development Company, L.P.
6  * Copyright (C) 2005, 2006 IBM Corporation
7  * All Rights Reserved.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
22  *
23  * Written by Rickard E. (Rik) Faith <faith@redhat.com>
24  *
25  * Many of the ideas implemented here are from Stephen C. Tweedie,
26  * especially the idea of avoiding a copy by using getname.
27  *
28  * The method for actual interception of syscall entry and exit (not in
29  * this file -- see entry.S) is based on a GPL'd patch written by
30  * okir@suse.de and Copyright 2003 SuSE Linux AG.
31  *
32  * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>,
33  * 2006.
34  *
35  * The support of additional filter rules compares (>, <, >=, <=) was
36  * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005.
37  *
38  * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional
39  * filesystem information.
40  *
41  * Subject and object context labeling support added by <danjones@us.ibm.com>
42  * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance.
43  */
44 
45 #include <linux/init.h>
46 #include <asm/types.h>
47 #include <linux/atomic.h>
48 #include <linux/fs.h>
49 #include <linux/namei.h>
50 #include <linux/mm.h>
51 #include <linux/export.h>
52 #include <linux/slab.h>
53 #include <linux/mount.h>
54 #include <linux/socket.h>
55 #include <linux/mqueue.h>
56 #include <linux/audit.h>
57 #include <linux/personality.h>
58 #include <linux/time.h>
59 #include <linux/netlink.h>
60 #include <linux/compiler.h>
61 #include <asm/unistd.h>
62 #include <linux/security.h>
63 #include <linux/list.h>
64 #include <linux/tty.h>
65 #include <linux/binfmts.h>
66 #include <linux/highmem.h>
67 #include <linux/syscalls.h>
68 #include <linux/capability.h>
69 #include <linux/fs_struct.h>
70 #include <linux/compat.h>
71 
72 #include "audit.h"
73 
74 /* flags stating the success for a syscall */
75 #define AUDITSC_INVALID 0
76 #define AUDITSC_SUCCESS 1
77 #define AUDITSC_FAILURE 2
78 
79 /* no execve audit message should be longer than this (userspace limits) */
80 #define MAX_EXECVE_AUDIT_LEN 7500
81 
82 /* number of audit rules */
83 int audit_n_rules;
84 
85 /* determines whether we collect data for signals sent */
86 int audit_signals;
87 
88 struct audit_aux_data {
89 	struct audit_aux_data	*next;
90 	int			type;
91 };
92 
93 #define AUDIT_AUX_IPCPERM	0
94 
95 /* Number of target pids per aux struct. */
96 #define AUDIT_AUX_PIDS	16
97 
98 struct audit_aux_data_execve {
99 	struct audit_aux_data	d;
100 	int argc;
101 	int envc;
102 	struct mm_struct *mm;
103 };
104 
105 struct audit_aux_data_pids {
106 	struct audit_aux_data	d;
107 	pid_t			target_pid[AUDIT_AUX_PIDS];
108 	kuid_t			target_auid[AUDIT_AUX_PIDS];
109 	kuid_t			target_uid[AUDIT_AUX_PIDS];
110 	unsigned int		target_sessionid[AUDIT_AUX_PIDS];
111 	u32			target_sid[AUDIT_AUX_PIDS];
112 	char 			target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
113 	int			pid_count;
114 };
115 
116 struct audit_aux_data_bprm_fcaps {
117 	struct audit_aux_data	d;
118 	struct audit_cap_data	fcap;
119 	unsigned int		fcap_ver;
120 	struct audit_cap_data	old_pcap;
121 	struct audit_cap_data	new_pcap;
122 };
123 
124 struct audit_aux_data_capset {
125 	struct audit_aux_data	d;
126 	pid_t			pid;
127 	struct audit_cap_data	cap;
128 };
129 
130 struct audit_tree_refs {
131 	struct audit_tree_refs *next;
132 	struct audit_chunk *c[31];
133 };
134 
135 static inline int open_arg(int flags, int mask)
136 {
137 	int n = ACC_MODE(flags);
138 	if (flags & (O_TRUNC | O_CREAT))
139 		n |= AUDIT_PERM_WRITE;
140 	return n & mask;
141 }
142 
143 static int audit_match_perm(struct audit_context *ctx, int mask)
144 {
145 	unsigned n;
146 	if (unlikely(!ctx))
147 		return 0;
148 	n = ctx->major;
149 
150 	switch (audit_classify_syscall(ctx->arch, n)) {
151 	case 0:	/* native */
152 		if ((mask & AUDIT_PERM_WRITE) &&
153 		     audit_match_class(AUDIT_CLASS_WRITE, n))
154 			return 1;
155 		if ((mask & AUDIT_PERM_READ) &&
156 		     audit_match_class(AUDIT_CLASS_READ, n))
157 			return 1;
158 		if ((mask & AUDIT_PERM_ATTR) &&
159 		     audit_match_class(AUDIT_CLASS_CHATTR, n))
160 			return 1;
161 		return 0;
162 	case 1: /* 32bit on biarch */
163 		if ((mask & AUDIT_PERM_WRITE) &&
164 		     audit_match_class(AUDIT_CLASS_WRITE_32, n))
165 			return 1;
166 		if ((mask & AUDIT_PERM_READ) &&
167 		     audit_match_class(AUDIT_CLASS_READ_32, n))
168 			return 1;
169 		if ((mask & AUDIT_PERM_ATTR) &&
170 		     audit_match_class(AUDIT_CLASS_CHATTR_32, n))
171 			return 1;
172 		return 0;
173 	case 2: /* open */
174 		return mask & ACC_MODE(ctx->argv[1]);
175 	case 3: /* openat */
176 		return mask & ACC_MODE(ctx->argv[2]);
177 	case 4: /* socketcall */
178 		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
179 	case 5: /* execve */
180 		return mask & AUDIT_PERM_EXEC;
181 	default:
182 		return 0;
183 	}
184 }
185 
186 static int audit_match_filetype(struct audit_context *ctx, int val)
187 {
188 	struct audit_names *n;
189 	umode_t mode = (umode_t)val;
190 
191 	if (unlikely(!ctx))
192 		return 0;
193 
194 	list_for_each_entry(n, &ctx->names_list, list) {
195 		if ((n->ino != -1) &&
196 		    ((n->mode & S_IFMT) == mode))
197 			return 1;
198 	}
199 
200 	return 0;
201 }
202 
203 /*
204  * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
205  * ->first_trees points to its beginning, ->trees - to the current end of data.
206  * ->tree_count is the number of free entries in array pointed to by ->trees.
207  * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
208  * "empty" becomes (p, p, 31) afterwards.  We don't shrink the list (and seriously,
209  * it's going to remain 1-element for almost any setup) until we free context itself.
210  * References in it _are_ dropped - at the same time we free/drop aux stuff.
211  */
212 
213 #ifdef CONFIG_AUDIT_TREE
214 static void audit_set_auditable(struct audit_context *ctx)
215 {
216 	if (!ctx->prio) {
217 		ctx->prio = 1;
218 		ctx->current_state = AUDIT_RECORD_CONTEXT;
219 	}
220 }
221 
222 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
223 {
224 	struct audit_tree_refs *p = ctx->trees;
225 	int left = ctx->tree_count;
226 	if (likely(left)) {
227 		p->c[--left] = chunk;
228 		ctx->tree_count = left;
229 		return 1;
230 	}
231 	if (!p)
232 		return 0;
233 	p = p->next;
234 	if (p) {
235 		p->c[30] = chunk;
236 		ctx->trees = p;
237 		ctx->tree_count = 30;
238 		return 1;
239 	}
240 	return 0;
241 }
242 
243 static int grow_tree_refs(struct audit_context *ctx)
244 {
245 	struct audit_tree_refs *p = ctx->trees;
246 	ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
247 	if (!ctx->trees) {
248 		ctx->trees = p;
249 		return 0;
250 	}
251 	if (p)
252 		p->next = ctx->trees;
253 	else
254 		ctx->first_trees = ctx->trees;
255 	ctx->tree_count = 31;
256 	return 1;
257 }
258 #endif
259 
260 static void unroll_tree_refs(struct audit_context *ctx,
261 		      struct audit_tree_refs *p, int count)
262 {
263 #ifdef CONFIG_AUDIT_TREE
264 	struct audit_tree_refs *q;
265 	int n;
266 	if (!p) {
267 		/* we started with empty chain */
268 		p = ctx->first_trees;
269 		count = 31;
270 		/* if the very first allocation has failed, nothing to do */
271 		if (!p)
272 			return;
273 	}
274 	n = count;
275 	for (q = p; q != ctx->trees; q = q->next, n = 31) {
276 		while (n--) {
277 			audit_put_chunk(q->c[n]);
278 			q->c[n] = NULL;
279 		}
280 	}
281 	while (n-- > ctx->tree_count) {
282 		audit_put_chunk(q->c[n]);
283 		q->c[n] = NULL;
284 	}
285 	ctx->trees = p;
286 	ctx->tree_count = count;
287 #endif
288 }
289 
290 static void free_tree_refs(struct audit_context *ctx)
291 {
292 	struct audit_tree_refs *p, *q;
293 	for (p = ctx->first_trees; p; p = q) {
294 		q = p->next;
295 		kfree(p);
296 	}
297 }
298 
299 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
300 {
301 #ifdef CONFIG_AUDIT_TREE
302 	struct audit_tree_refs *p;
303 	int n;
304 	if (!tree)
305 		return 0;
306 	/* full ones */
307 	for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
308 		for (n = 0; n < 31; n++)
309 			if (audit_tree_match(p->c[n], tree))
310 				return 1;
311 	}
312 	/* partial */
313 	if (p) {
314 		for (n = ctx->tree_count; n < 31; n++)
315 			if (audit_tree_match(p->c[n], tree))
316 				return 1;
317 	}
318 #endif
319 	return 0;
320 }
321 
322 static int audit_compare_uid(kuid_t uid,
323 			     struct audit_names *name,
324 			     struct audit_field *f,
325 			     struct audit_context *ctx)
326 {
327 	struct audit_names *n;
328 	int rc;
329 
330 	if (name) {
331 		rc = audit_uid_comparator(uid, f->op, name->uid);
332 		if (rc)
333 			return rc;
334 	}
335 
336 	if (ctx) {
337 		list_for_each_entry(n, &ctx->names_list, list) {
338 			rc = audit_uid_comparator(uid, f->op, n->uid);
339 			if (rc)
340 				return rc;
341 		}
342 	}
343 	return 0;
344 }
345 
346 static int audit_compare_gid(kgid_t gid,
347 			     struct audit_names *name,
348 			     struct audit_field *f,
349 			     struct audit_context *ctx)
350 {
351 	struct audit_names *n;
352 	int rc;
353 
354 	if (name) {
355 		rc = audit_gid_comparator(gid, f->op, name->gid);
356 		if (rc)
357 			return rc;
358 	}
359 
360 	if (ctx) {
361 		list_for_each_entry(n, &ctx->names_list, list) {
362 			rc = audit_gid_comparator(gid, f->op, n->gid);
363 			if (rc)
364 				return rc;
365 		}
366 	}
367 	return 0;
368 }
369 
370 static int audit_field_compare(struct task_struct *tsk,
371 			       const struct cred *cred,
372 			       struct audit_field *f,
373 			       struct audit_context *ctx,
374 			       struct audit_names *name)
375 {
376 	switch (f->val) {
377 	/* process to file object comparisons */
378 	case AUDIT_COMPARE_UID_TO_OBJ_UID:
379 		return audit_compare_uid(cred->uid, name, f, ctx);
380 	case AUDIT_COMPARE_GID_TO_OBJ_GID:
381 		return audit_compare_gid(cred->gid, name, f, ctx);
382 	case AUDIT_COMPARE_EUID_TO_OBJ_UID:
383 		return audit_compare_uid(cred->euid, name, f, ctx);
384 	case AUDIT_COMPARE_EGID_TO_OBJ_GID:
385 		return audit_compare_gid(cred->egid, name, f, ctx);
386 	case AUDIT_COMPARE_AUID_TO_OBJ_UID:
387 		return audit_compare_uid(tsk->loginuid, name, f, ctx);
388 	case AUDIT_COMPARE_SUID_TO_OBJ_UID:
389 		return audit_compare_uid(cred->suid, name, f, ctx);
390 	case AUDIT_COMPARE_SGID_TO_OBJ_GID:
391 		return audit_compare_gid(cred->sgid, name, f, ctx);
392 	case AUDIT_COMPARE_FSUID_TO_OBJ_UID:
393 		return audit_compare_uid(cred->fsuid, name, f, ctx);
394 	case AUDIT_COMPARE_FSGID_TO_OBJ_GID:
395 		return audit_compare_gid(cred->fsgid, name, f, ctx);
396 	/* uid comparisons */
397 	case AUDIT_COMPARE_UID_TO_AUID:
398 		return audit_uid_comparator(cred->uid, f->op, tsk->loginuid);
399 	case AUDIT_COMPARE_UID_TO_EUID:
400 		return audit_uid_comparator(cred->uid, f->op, cred->euid);
401 	case AUDIT_COMPARE_UID_TO_SUID:
402 		return audit_uid_comparator(cred->uid, f->op, cred->suid);
403 	case AUDIT_COMPARE_UID_TO_FSUID:
404 		return audit_uid_comparator(cred->uid, f->op, cred->fsuid);
405 	/* auid comparisons */
406 	case AUDIT_COMPARE_AUID_TO_EUID:
407 		return audit_uid_comparator(tsk->loginuid, f->op, cred->euid);
408 	case AUDIT_COMPARE_AUID_TO_SUID:
409 		return audit_uid_comparator(tsk->loginuid, f->op, cred->suid);
410 	case AUDIT_COMPARE_AUID_TO_FSUID:
411 		return audit_uid_comparator(tsk->loginuid, f->op, cred->fsuid);
412 	/* euid comparisons */
413 	case AUDIT_COMPARE_EUID_TO_SUID:
414 		return audit_uid_comparator(cred->euid, f->op, cred->suid);
415 	case AUDIT_COMPARE_EUID_TO_FSUID:
416 		return audit_uid_comparator(cred->euid, f->op, cred->fsuid);
417 	/* suid comparisons */
418 	case AUDIT_COMPARE_SUID_TO_FSUID:
419 		return audit_uid_comparator(cred->suid, f->op, cred->fsuid);
420 	/* gid comparisons */
421 	case AUDIT_COMPARE_GID_TO_EGID:
422 		return audit_gid_comparator(cred->gid, f->op, cred->egid);
423 	case AUDIT_COMPARE_GID_TO_SGID:
424 		return audit_gid_comparator(cred->gid, f->op, cred->sgid);
425 	case AUDIT_COMPARE_GID_TO_FSGID:
426 		return audit_gid_comparator(cred->gid, f->op, cred->fsgid);
427 	/* egid comparisons */
428 	case AUDIT_COMPARE_EGID_TO_SGID:
429 		return audit_gid_comparator(cred->egid, f->op, cred->sgid);
430 	case AUDIT_COMPARE_EGID_TO_FSGID:
431 		return audit_gid_comparator(cred->egid, f->op, cred->fsgid);
432 	/* sgid comparison */
433 	case AUDIT_COMPARE_SGID_TO_FSGID:
434 		return audit_gid_comparator(cred->sgid, f->op, cred->fsgid);
435 	default:
436 		WARN(1, "Missing AUDIT_COMPARE define.  Report as a bug\n");
437 		return 0;
438 	}
439 	return 0;
440 }
441 
442 /* Determine if any context name data matches a rule's watch data */
443 /* Compare a task_struct with an audit_rule.  Return 1 on match, 0
444  * otherwise.
445  *
446  * If task_creation is true, this is an explicit indication that we are
447  * filtering a task rule at task creation time.  This and tsk == current are
448  * the only situations where tsk->cred may be accessed without an rcu read lock.
449  */
450 static int audit_filter_rules(struct task_struct *tsk,
451 			      struct audit_krule *rule,
452 			      struct audit_context *ctx,
453 			      struct audit_names *name,
454 			      enum audit_state *state,
455 			      bool task_creation)
456 {
457 	const struct cred *cred;
458 	int i, need_sid = 1;
459 	u32 sid;
460 
461 	cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);
462 
463 	for (i = 0; i < rule->field_count; i++) {
464 		struct audit_field *f = &rule->fields[i];
465 		struct audit_names *n;
466 		int result = 0;
467 
468 		switch (f->type) {
469 		case AUDIT_PID:
470 			result = audit_comparator(tsk->pid, f->op, f->val);
471 			break;
472 		case AUDIT_PPID:
473 			if (ctx) {
474 				if (!ctx->ppid)
475 					ctx->ppid = sys_getppid();
476 				result = audit_comparator(ctx->ppid, f->op, f->val);
477 			}
478 			break;
479 		case AUDIT_UID:
480 			result = audit_uid_comparator(cred->uid, f->op, f->uid);
481 			break;
482 		case AUDIT_EUID:
483 			result = audit_uid_comparator(cred->euid, f->op, f->uid);
484 			break;
485 		case AUDIT_SUID:
486 			result = audit_uid_comparator(cred->suid, f->op, f->uid);
487 			break;
488 		case AUDIT_FSUID:
489 			result = audit_uid_comparator(cred->fsuid, f->op, f->uid);
490 			break;
491 		case AUDIT_GID:
492 			result = audit_gid_comparator(cred->gid, f->op, f->gid);
493 			if (f->op == Audit_equal) {
494 				if (!result)
495 					result = in_group_p(f->gid);
496 			} else if (f->op == Audit_not_equal) {
497 				if (result)
498 					result = !in_group_p(f->gid);
499 			}
500 			break;
501 		case AUDIT_EGID:
502 			result = audit_gid_comparator(cred->egid, f->op, f->gid);
503 			if (f->op == Audit_equal) {
504 				if (!result)
505 					result = in_egroup_p(f->gid);
506 			} else if (f->op == Audit_not_equal) {
507 				if (result)
508 					result = !in_egroup_p(f->gid);
509 			}
510 			break;
511 		case AUDIT_SGID:
512 			result = audit_gid_comparator(cred->sgid, f->op, f->gid);
513 			break;
514 		case AUDIT_FSGID:
515 			result = audit_gid_comparator(cred->fsgid, f->op, f->gid);
516 			break;
517 		case AUDIT_PERS:
518 			result = audit_comparator(tsk->personality, f->op, f->val);
519 			break;
520 		case AUDIT_ARCH:
521 			if (ctx)
522 				result = audit_comparator(ctx->arch, f->op, f->val);
523 			break;
524 
525 		case AUDIT_EXIT:
526 			if (ctx && ctx->return_valid)
527 				result = audit_comparator(ctx->return_code, f->op, f->val);
528 			break;
529 		case AUDIT_SUCCESS:
530 			if (ctx && ctx->return_valid) {
531 				if (f->val)
532 					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
533 				else
534 					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
535 			}
536 			break;
537 		case AUDIT_DEVMAJOR:
538 			if (name) {
539 				if (audit_comparator(MAJOR(name->dev), f->op, f->val) ||
540 				    audit_comparator(MAJOR(name->rdev), f->op, f->val))
541 					++result;
542 			} else if (ctx) {
543 				list_for_each_entry(n, &ctx->names_list, list) {
544 					if (audit_comparator(MAJOR(n->dev), f->op, f->val) ||
545 					    audit_comparator(MAJOR(n->rdev), f->op, f->val)) {
546 						++result;
547 						break;
548 					}
549 				}
550 			}
551 			break;
552 		case AUDIT_DEVMINOR:
553 			if (name) {
554 				if (audit_comparator(MINOR(name->dev), f->op, f->val) ||
555 				    audit_comparator(MINOR(name->rdev), f->op, f->val))
556 					++result;
557 			} else if (ctx) {
558 				list_for_each_entry(n, &ctx->names_list, list) {
559 					if (audit_comparator(MINOR(n->dev), f->op, f->val) ||
560 					    audit_comparator(MINOR(n->rdev), f->op, f->val)) {
561 						++result;
562 						break;
563 					}
564 				}
565 			}
566 			break;
567 		case AUDIT_INODE:
568 			if (name)
569 				result = (name->ino == f->val);
570 			else if (ctx) {
571 				list_for_each_entry(n, &ctx->names_list, list) {
572 					if (audit_comparator(n->ino, f->op, f->val)) {
573 						++result;
574 						break;
575 					}
576 				}
577 			}
578 			break;
579 		case AUDIT_OBJ_UID:
580 			if (name) {
581 				result = audit_uid_comparator(name->uid, f->op, f->uid);
582 			} else if (ctx) {
583 				list_for_each_entry(n, &ctx->names_list, list) {
584 					if (audit_uid_comparator(n->uid, f->op, f->uid)) {
585 						++result;
586 						break;
587 					}
588 				}
589 			}
590 			break;
591 		case AUDIT_OBJ_GID:
592 			if (name) {
593 				result = audit_gid_comparator(name->gid, f->op, f->gid);
594 			} else if (ctx) {
595 				list_for_each_entry(n, &ctx->names_list, list) {
596 					if (audit_gid_comparator(n->gid, f->op, f->gid)) {
597 						++result;
598 						break;
599 					}
600 				}
601 			}
602 			break;
603 		case AUDIT_WATCH:
604 			if (name)
605 				result = audit_watch_compare(rule->watch, name->ino, name->dev);
606 			break;
607 		case AUDIT_DIR:
608 			if (ctx)
609 				result = match_tree_refs(ctx, rule->tree);
610 			break;
611 		case AUDIT_LOGINUID:
612 			result = 0;
613 			if (ctx)
614 				result = audit_uid_comparator(tsk->loginuid, f->op, f->uid);
615 			break;
616 		case AUDIT_LOGINUID_SET:
617 			result = audit_comparator(audit_loginuid_set(tsk), f->op, f->val);
618 			break;
619 		case AUDIT_SUBJ_USER:
620 		case AUDIT_SUBJ_ROLE:
621 		case AUDIT_SUBJ_TYPE:
622 		case AUDIT_SUBJ_SEN:
623 		case AUDIT_SUBJ_CLR:
624 			/* NOTE: this may return negative values indicating
625 			   a temporary error.  We simply treat this as a
626 			   match for now to avoid losing information that
627 			   may be wanted.   An error message will also be
628 			   logged upon error */
629 			if (f->lsm_rule) {
630 				if (need_sid) {
631 					security_task_getsecid(tsk, &sid);
632 					need_sid = 0;
633 				}
634 				result = security_audit_rule_match(sid, f->type,
635 				                                  f->op,
636 				                                  f->lsm_rule,
637 				                                  ctx);
638 			}
639 			break;
640 		case AUDIT_OBJ_USER:
641 		case AUDIT_OBJ_ROLE:
642 		case AUDIT_OBJ_TYPE:
643 		case AUDIT_OBJ_LEV_LOW:
644 		case AUDIT_OBJ_LEV_HIGH:
645 			/* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
646 			   also applies here */
647 			if (f->lsm_rule) {
648 				/* Find files that match */
649 				if (name) {
650 					result = security_audit_rule_match(
651 					           name->osid, f->type, f->op,
652 					           f->lsm_rule, ctx);
653 				} else if (ctx) {
654 					list_for_each_entry(n, &ctx->names_list, list) {
655 						if (security_audit_rule_match(n->osid, f->type,
656 									      f->op, f->lsm_rule,
657 									      ctx)) {
658 							++result;
659 							break;
660 						}
661 					}
662 				}
663 				/* Find ipc objects that match */
664 				if (!ctx || ctx->type != AUDIT_IPC)
665 					break;
666 				if (security_audit_rule_match(ctx->ipc.osid,
667 							      f->type, f->op,
668 							      f->lsm_rule, ctx))
669 					++result;
670 			}
671 			break;
672 		case AUDIT_ARG0:
673 		case AUDIT_ARG1:
674 		case AUDIT_ARG2:
675 		case AUDIT_ARG3:
676 			if (ctx)
677 				result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
678 			break;
679 		case AUDIT_FILTERKEY:
680 			/* ignore this field for filtering */
681 			result = 1;
682 			break;
683 		case AUDIT_PERM:
684 			result = audit_match_perm(ctx, f->val);
685 			break;
686 		case AUDIT_FILETYPE:
687 			result = audit_match_filetype(ctx, f->val);
688 			break;
689 		case AUDIT_FIELD_COMPARE:
690 			result = audit_field_compare(tsk, cred, f, ctx, name);
691 			break;
692 		}
693 		if (!result)
694 			return 0;
695 	}
696 
697 	if (ctx) {
698 		if (rule->prio <= ctx->prio)
699 			return 0;
700 		if (rule->filterkey) {
701 			kfree(ctx->filterkey);
702 			ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
703 		}
704 		ctx->prio = rule->prio;
705 	}
706 	switch (rule->action) {
707 	case AUDIT_NEVER:    *state = AUDIT_DISABLED;	    break;
708 	case AUDIT_ALWAYS:   *state = AUDIT_RECORD_CONTEXT; break;
709 	}
710 	return 1;
711 }
712 
713 /* At process creation time, we can determine if system-call auditing is
714  * completely disabled for this task.  Since we only have the task
715  * structure at this point, we can only check uid and gid.
716  */
717 static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
718 {
719 	struct audit_entry *e;
720 	enum audit_state   state;
721 
722 	rcu_read_lock();
723 	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
724 		if (audit_filter_rules(tsk, &e->rule, NULL, NULL,
725 				       &state, true)) {
726 			if (state == AUDIT_RECORD_CONTEXT)
727 				*key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
728 			rcu_read_unlock();
729 			return state;
730 		}
731 	}
732 	rcu_read_unlock();
733 	return AUDIT_BUILD_CONTEXT;
734 }
735 
736 /* At syscall entry and exit time, this filter is called if the
737  * audit_state is not low enough that auditing cannot take place, but is
738  * also not high enough that we already know we have to write an audit
739  * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
740  */
741 static enum audit_state audit_filter_syscall(struct task_struct *tsk,
742 					     struct audit_context *ctx,
743 					     struct list_head *list)
744 {
745 	struct audit_entry *e;
746 	enum audit_state state;
747 
748 	if (audit_pid && tsk->tgid == audit_pid)
749 		return AUDIT_DISABLED;
750 
751 	rcu_read_lock();
752 	if (!list_empty(list)) {
753 		int word = AUDIT_WORD(ctx->major);
754 		int bit  = AUDIT_BIT(ctx->major);
755 
756 		list_for_each_entry_rcu(e, list, list) {
757 			if ((e->rule.mask[word] & bit) == bit &&
758 			    audit_filter_rules(tsk, &e->rule, ctx, NULL,
759 					       &state, false)) {
760 				rcu_read_unlock();
761 				ctx->current_state = state;
762 				return state;
763 			}
764 		}
765 	}
766 	rcu_read_unlock();
767 	return AUDIT_BUILD_CONTEXT;
768 }
769 
770 /*
771  * Given an audit_name check the inode hash table to see if they match.
772  * Called holding the rcu read lock to protect the use of audit_inode_hash
773  */
774 static int audit_filter_inode_name(struct task_struct *tsk,
775 				   struct audit_names *n,
776 				   struct audit_context *ctx) {
777 	int word, bit;
778 	int h = audit_hash_ino((u32)n->ino);
779 	struct list_head *list = &audit_inode_hash[h];
780 	struct audit_entry *e;
781 	enum audit_state state;
782 
783 	word = AUDIT_WORD(ctx->major);
784 	bit  = AUDIT_BIT(ctx->major);
785 
786 	if (list_empty(list))
787 		return 0;
788 
789 	list_for_each_entry_rcu(e, list, list) {
790 		if ((e->rule.mask[word] & bit) == bit &&
791 		    audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) {
792 			ctx->current_state = state;
793 			return 1;
794 		}
795 	}
796 
797 	return 0;
798 }
799 
800 /* At syscall exit time, this filter is called if any audit_names have been
801  * collected during syscall processing.  We only check rules in sublists at hash
802  * buckets applicable to the inode numbers in audit_names.
803  * Regarding audit_state, same rules apply as for audit_filter_syscall().
804  */
805 void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
806 {
807 	struct audit_names *n;
808 
809 	if (audit_pid && tsk->tgid == audit_pid)
810 		return;
811 
812 	rcu_read_lock();
813 
814 	list_for_each_entry(n, &ctx->names_list, list) {
815 		if (audit_filter_inode_name(tsk, n, ctx))
816 			break;
817 	}
818 	rcu_read_unlock();
819 }
820 
821 static inline struct audit_context *audit_get_context(struct task_struct *tsk,
822 						      int return_valid,
823 						      long return_code)
824 {
825 	struct audit_context *context = tsk->audit_context;
826 
827 	if (!context)
828 		return NULL;
829 	context->return_valid = return_valid;
830 
831 	/*
832 	 * we need to fix up the return code in the audit logs if the actual
833 	 * return codes are later going to be fixed up by the arch specific
834 	 * signal handlers
835 	 *
836 	 * This is actually a test for:
837 	 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
838 	 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
839 	 *
840 	 * but is faster than a bunch of ||
841 	 */
842 	if (unlikely(return_code <= -ERESTARTSYS) &&
843 	    (return_code >= -ERESTART_RESTARTBLOCK) &&
844 	    (return_code != -ENOIOCTLCMD))
845 		context->return_code = -EINTR;
846 	else
847 		context->return_code  = return_code;
848 
849 	if (context->in_syscall && !context->dummy) {
850 		audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
851 		audit_filter_inodes(tsk, context);
852 	}
853 
854 	tsk->audit_context = NULL;
855 	return context;
856 }
857 
858 static inline void audit_free_names(struct audit_context *context)
859 {
860 	struct audit_names *n, *next;
861 
862 #if AUDIT_DEBUG == 2
863 	if (context->put_count + context->ino_count != context->name_count) {
864 		int i = 0;
865 
866 		printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
867 		       " name_count=%d put_count=%d"
868 		       " ino_count=%d [NOT freeing]\n",
869 		       __FILE__, __LINE__,
870 		       context->serial, context->major, context->in_syscall,
871 		       context->name_count, context->put_count,
872 		       context->ino_count);
873 		list_for_each_entry(n, &context->names_list, list) {
874 			printk(KERN_ERR "names[%d] = %p = %s\n", i++,
875 			       n->name, n->name->name ?: "(null)");
876 		}
877 		dump_stack();
878 		return;
879 	}
880 #endif
881 #if AUDIT_DEBUG
882 	context->put_count  = 0;
883 	context->ino_count  = 0;
884 #endif
885 
886 	list_for_each_entry_safe(n, next, &context->names_list, list) {
887 		list_del(&n->list);
888 		if (n->name && n->name_put)
889 			final_putname(n->name);
890 		if (n->should_free)
891 			kfree(n);
892 	}
893 	context->name_count = 0;
894 	path_put(&context->pwd);
895 	context->pwd.dentry = NULL;
896 	context->pwd.mnt = NULL;
897 }
898 
899 static inline void audit_free_aux(struct audit_context *context)
900 {
901 	struct audit_aux_data *aux;
902 
903 	while ((aux = context->aux)) {
904 		context->aux = aux->next;
905 		kfree(aux);
906 	}
907 	while ((aux = context->aux_pids)) {
908 		context->aux_pids = aux->next;
909 		kfree(aux);
910 	}
911 }
912 
913 static inline struct audit_context *audit_alloc_context(enum audit_state state)
914 {
915 	struct audit_context *context;
916 
917 	context = kzalloc(sizeof(*context), GFP_KERNEL);
918 	if (!context)
919 		return NULL;
920 	context->state = state;
921 	context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
922 	INIT_LIST_HEAD(&context->killed_trees);
923 	INIT_LIST_HEAD(&context->names_list);
924 	return context;
925 }
926 
927 /**
928  * audit_alloc - allocate an audit context block for a task
929  * @tsk: task
930  *
931  * Filter on the task information and allocate a per-task audit context
932  * if necessary.  Doing so turns on system call auditing for the
933  * specified task.  This is called from copy_process, so no lock is
934  * needed.
935  */
936 int audit_alloc(struct task_struct *tsk)
937 {
938 	struct audit_context *context;
939 	enum audit_state     state;
940 	char *key = NULL;
941 
942 	if (likely(!audit_ever_enabled))
943 		return 0; /* Return if not auditing. */
944 
945 	state = audit_filter_task(tsk, &key);
946 	if (state == AUDIT_DISABLED)
947 		return 0;
948 
949 	if (!(context = audit_alloc_context(state))) {
950 		kfree(key);
951 		audit_log_lost("out of memory in audit_alloc");
952 		return -ENOMEM;
953 	}
954 	context->filterkey = key;
955 
956 	tsk->audit_context  = context;
957 	set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
958 	return 0;
959 }
960 
961 static inline void audit_free_context(struct audit_context *context)
962 {
963 	audit_free_names(context);
964 	unroll_tree_refs(context, NULL, 0);
965 	free_tree_refs(context);
966 	audit_free_aux(context);
967 	kfree(context->filterkey);
968 	kfree(context->sockaddr);
969 	kfree(context);
970 }
971 
972 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
973 				 kuid_t auid, kuid_t uid, unsigned int sessionid,
974 				 u32 sid, char *comm)
975 {
976 	struct audit_buffer *ab;
977 	char *ctx = NULL;
978 	u32 len;
979 	int rc = 0;
980 
981 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
982 	if (!ab)
983 		return rc;
984 
985 	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
986 			 from_kuid(&init_user_ns, auid),
987 			 from_kuid(&init_user_ns, uid), sessionid);
988 	if (sid) {
989 		if (security_secid_to_secctx(sid, &ctx, &len)) {
990 			audit_log_format(ab, " obj=(none)");
991 			rc = 1;
992 		} else {
993 			audit_log_format(ab, " obj=%s", ctx);
994 			security_release_secctx(ctx, len);
995 		}
996 	}
997 	audit_log_format(ab, " ocomm=");
998 	audit_log_untrustedstring(ab, comm);
999 	audit_log_end(ab);
1000 
1001 	return rc;
1002 }
1003 
1004 /*
1005  * to_send and len_sent accounting are very loose estimates.  We aren't
1006  * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being
1007  * within about 500 bytes (next page boundary)
1008  *
1009  * why snprintf?  an int is up to 12 digits long.  if we just assumed when
1010  * logging that a[%d]= was going to be 16 characters long we would be wasting
1011  * space in every audit message.  In one 7500 byte message we can log up to
1012  * about 1000 min size arguments.  That comes down to about 50% waste of space
1013  * if we didn't do the snprintf to find out how long arg_num_len was.
1014  */
1015 static int audit_log_single_execve_arg(struct audit_context *context,
1016 					struct audit_buffer **ab,
1017 					int arg_num,
1018 					size_t *len_sent,
1019 					const char __user *p,
1020 					char *buf)
1021 {
1022 	char arg_num_len_buf[12];
1023 	const char __user *tmp_p = p;
1024 	/* how many digits are in arg_num? 5 is the length of ' a=""' */
1025 	size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 5;
1026 	size_t len, len_left, to_send;
1027 	size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN;
1028 	unsigned int i, has_cntl = 0, too_long = 0;
1029 	int ret;
1030 
1031 	/* strnlen_user includes the null we don't want to send */
1032 	len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1033 
1034 	/*
1035 	 * We just created this mm, if we can't find the strings
1036 	 * we just copied into it something is _very_ wrong. Similar
1037 	 * for strings that are too long, we should not have created
1038 	 * any.
1039 	 */
1040 	if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
1041 		WARN_ON(1);
1042 		send_sig(SIGKILL, current, 0);
1043 		return -1;
1044 	}
1045 
1046 	/* walk the whole argument looking for non-ascii chars */
1047 	do {
1048 		if (len_left > MAX_EXECVE_AUDIT_LEN)
1049 			to_send = MAX_EXECVE_AUDIT_LEN;
1050 		else
1051 			to_send = len_left;
1052 		ret = copy_from_user(buf, tmp_p, to_send);
1053 		/*
1054 		 * There is no reason for this copy to be short. We just
1055 		 * copied them here, and the mm hasn't been exposed to user-
1056 		 * space yet.
1057 		 */
1058 		if (ret) {
1059 			WARN_ON(1);
1060 			send_sig(SIGKILL, current, 0);
1061 			return -1;
1062 		}
1063 		buf[to_send] = '\0';
1064 		has_cntl = audit_string_contains_control(buf, to_send);
1065 		if (has_cntl) {
1066 			/*
1067 			 * hex messages get logged as 2 bytes, so we can only
1068 			 * send half as much in each message
1069 			 */
1070 			max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2;
1071 			break;
1072 		}
1073 		len_left -= to_send;
1074 		tmp_p += to_send;
1075 	} while (len_left > 0);
1076 
1077 	len_left = len;
1078 
1079 	if (len > max_execve_audit_len)
1080 		too_long = 1;
1081 
1082 	/* rewalk the argument actually logging the message */
1083 	for (i = 0; len_left > 0; i++) {
1084 		int room_left;
1085 
1086 		if (len_left > max_execve_audit_len)
1087 			to_send = max_execve_audit_len;
1088 		else
1089 			to_send = len_left;
1090 
1091 		/* do we have space left to send this argument in this ab? */
1092 		room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent;
1093 		if (has_cntl)
1094 			room_left -= (to_send * 2);
1095 		else
1096 			room_left -= to_send;
1097 		if (room_left < 0) {
1098 			*len_sent = 0;
1099 			audit_log_end(*ab);
1100 			*ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE);
1101 			if (!*ab)
1102 				return 0;
1103 		}
1104 
1105 		/*
1106 		 * first record needs to say how long the original string was
1107 		 * so we can be sure nothing was lost.
1108 		 */
1109 		if ((i == 0) && (too_long))
1110 			audit_log_format(*ab, " a%d_len=%zu", arg_num,
1111 					 has_cntl ? 2*len : len);
1112 
1113 		/*
1114 		 * normally arguments are small enough to fit and we already
1115 		 * filled buf above when we checked for control characters
1116 		 * so don't bother with another copy_from_user
1117 		 */
1118 		if (len >= max_execve_audit_len)
1119 			ret = copy_from_user(buf, p, to_send);
1120 		else
1121 			ret = 0;
1122 		if (ret) {
1123 			WARN_ON(1);
1124 			send_sig(SIGKILL, current, 0);
1125 			return -1;
1126 		}
1127 		buf[to_send] = '\0';
1128 
1129 		/* actually log it */
1130 		audit_log_format(*ab, " a%d", arg_num);
1131 		if (too_long)
1132 			audit_log_format(*ab, "[%d]", i);
1133 		audit_log_format(*ab, "=");
1134 		if (has_cntl)
1135 			audit_log_n_hex(*ab, buf, to_send);
1136 		else
1137 			audit_log_string(*ab, buf);
1138 
1139 		p += to_send;
1140 		len_left -= to_send;
1141 		*len_sent += arg_num_len;
1142 		if (has_cntl)
1143 			*len_sent += to_send * 2;
1144 		else
1145 			*len_sent += to_send;
1146 	}
1147 	/* include the null we didn't log */
1148 	return len + 1;
1149 }
1150 
1151 static void audit_log_execve_info(struct audit_context *context,
1152 				  struct audit_buffer **ab,
1153 				  struct audit_aux_data_execve *axi)
1154 {
1155 	int i, len;
1156 	size_t len_sent = 0;
1157 	const char __user *p;
1158 	char *buf;
1159 
1160 	if (axi->mm != current->mm)
1161 		return; /* execve failed, no additional info */
1162 
1163 	p = (const char __user *)axi->mm->arg_start;
1164 
1165 	audit_log_format(*ab, "argc=%d", axi->argc);
1166 
1167 	/*
1168 	 * we need some kernel buffer to hold the userspace args.  Just
1169 	 * allocate one big one rather than allocating one of the right size
1170 	 * for every single argument inside audit_log_single_execve_arg()
1171 	 * should be <8k allocation so should be pretty safe.
1172 	 */
1173 	buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1174 	if (!buf) {
1175 		audit_panic("out of memory for argv string\n");
1176 		return;
1177 	}
1178 
1179 	for (i = 0; i < axi->argc; i++) {
1180 		len = audit_log_single_execve_arg(context, ab, i,
1181 						  &len_sent, p, buf);
1182 		if (len <= 0)
1183 			break;
1184 		p += len;
1185 	}
1186 	kfree(buf);
1187 }
1188 
1189 static void show_special(struct audit_context *context, int *call_panic)
1190 {
1191 	struct audit_buffer *ab;
1192 	int i;
1193 
1194 	ab = audit_log_start(context, GFP_KERNEL, context->type);
1195 	if (!ab)
1196 		return;
1197 
1198 	switch (context->type) {
1199 	case AUDIT_SOCKETCALL: {
1200 		int nargs = context->socketcall.nargs;
1201 		audit_log_format(ab, "nargs=%d", nargs);
1202 		for (i = 0; i < nargs; i++)
1203 			audit_log_format(ab, " a%d=%lx", i,
1204 				context->socketcall.args[i]);
1205 		break; }
1206 	case AUDIT_IPC: {
1207 		u32 osid = context->ipc.osid;
1208 
1209 		audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
1210 				 from_kuid(&init_user_ns, context->ipc.uid),
1211 				 from_kgid(&init_user_ns, context->ipc.gid),
1212 				 context->ipc.mode);
1213 		if (osid) {
1214 			char *ctx = NULL;
1215 			u32 len;
1216 			if (security_secid_to_secctx(osid, &ctx, &len)) {
1217 				audit_log_format(ab, " osid=%u", osid);
1218 				*call_panic = 1;
1219 			} else {
1220 				audit_log_format(ab, " obj=%s", ctx);
1221 				security_release_secctx(ctx, len);
1222 			}
1223 		}
1224 		if (context->ipc.has_perm) {
1225 			audit_log_end(ab);
1226 			ab = audit_log_start(context, GFP_KERNEL,
1227 					     AUDIT_IPC_SET_PERM);
1228 			if (unlikely(!ab))
1229 				return;
1230 			audit_log_format(ab,
1231 				"qbytes=%lx ouid=%u ogid=%u mode=%#ho",
1232 				context->ipc.qbytes,
1233 				context->ipc.perm_uid,
1234 				context->ipc.perm_gid,
1235 				context->ipc.perm_mode);
1236 		}
1237 		break; }
1238 	case AUDIT_MQ_OPEN: {
1239 		audit_log_format(ab,
1240 			"oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "
1241 			"mq_msgsize=%ld mq_curmsgs=%ld",
1242 			context->mq_open.oflag, context->mq_open.mode,
1243 			context->mq_open.attr.mq_flags,
1244 			context->mq_open.attr.mq_maxmsg,
1245 			context->mq_open.attr.mq_msgsize,
1246 			context->mq_open.attr.mq_curmsgs);
1247 		break; }
1248 	case AUDIT_MQ_SENDRECV: {
1249 		audit_log_format(ab,
1250 			"mqdes=%d msg_len=%zd msg_prio=%u "
1251 			"abs_timeout_sec=%ld abs_timeout_nsec=%ld",
1252 			context->mq_sendrecv.mqdes,
1253 			context->mq_sendrecv.msg_len,
1254 			context->mq_sendrecv.msg_prio,
1255 			context->mq_sendrecv.abs_timeout.tv_sec,
1256 			context->mq_sendrecv.abs_timeout.tv_nsec);
1257 		break; }
1258 	case AUDIT_MQ_NOTIFY: {
1259 		audit_log_format(ab, "mqdes=%d sigev_signo=%d",
1260 				context->mq_notify.mqdes,
1261 				context->mq_notify.sigev_signo);
1262 		break; }
1263 	case AUDIT_MQ_GETSETATTR: {
1264 		struct mq_attr *attr = &context->mq_getsetattr.mqstat;
1265 		audit_log_format(ab,
1266 			"mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1267 			"mq_curmsgs=%ld ",
1268 			context->mq_getsetattr.mqdes,
1269 			attr->mq_flags, attr->mq_maxmsg,
1270 			attr->mq_msgsize, attr->mq_curmsgs);
1271 		break; }
1272 	case AUDIT_CAPSET: {
1273 		audit_log_format(ab, "pid=%d", context->capset.pid);
1274 		audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
1275 		audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
1276 		audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
1277 		break; }
1278 	case AUDIT_MMAP: {
1279 		audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
1280 				 context->mmap.flags);
1281 		break; }
1282 	}
1283 	audit_log_end(ab);
1284 }
1285 
1286 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
1287 {
1288 	int i, call_panic = 0;
1289 	struct audit_buffer *ab;
1290 	struct audit_aux_data *aux;
1291 	struct audit_names *n;
1292 
1293 	/* tsk == current */
1294 	context->personality = tsk->personality;
1295 
1296 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1297 	if (!ab)
1298 		return;		/* audit_panic has been called */
1299 	audit_log_format(ab, "arch=%x syscall=%d",
1300 			 context->arch, context->major);
1301 	if (context->personality != PER_LINUX)
1302 		audit_log_format(ab, " per=%lx", context->personality);
1303 	if (context->return_valid)
1304 		audit_log_format(ab, " success=%s exit=%ld",
1305 				 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
1306 				 context->return_code);
1307 
1308 	audit_log_format(ab,
1309 			 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d",
1310 			 context->argv[0],
1311 			 context->argv[1],
1312 			 context->argv[2],
1313 			 context->argv[3],
1314 			 context->name_count);
1315 
1316 	audit_log_task_info(ab, tsk);
1317 	audit_log_key(ab, context->filterkey);
1318 	audit_log_end(ab);
1319 
1320 	for (aux = context->aux; aux; aux = aux->next) {
1321 
1322 		ab = audit_log_start(context, GFP_KERNEL, aux->type);
1323 		if (!ab)
1324 			continue; /* audit_panic has been called */
1325 
1326 		switch (aux->type) {
1327 
1328 		case AUDIT_EXECVE: {
1329 			struct audit_aux_data_execve *axi = (void *)aux;
1330 			audit_log_execve_info(context, &ab, axi);
1331 			break; }
1332 
1333 		case AUDIT_BPRM_FCAPS: {
1334 			struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
1335 			audit_log_format(ab, "fver=%x", axs->fcap_ver);
1336 			audit_log_cap(ab, "fp", &axs->fcap.permitted);
1337 			audit_log_cap(ab, "fi", &axs->fcap.inheritable);
1338 			audit_log_format(ab, " fe=%d", axs->fcap.fE);
1339 			audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
1340 			audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
1341 			audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
1342 			audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted);
1343 			audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable);
1344 			audit_log_cap(ab, "new_pe", &axs->new_pcap.effective);
1345 			break; }
1346 
1347 		}
1348 		audit_log_end(ab);
1349 	}
1350 
1351 	if (context->type)
1352 		show_special(context, &call_panic);
1353 
1354 	if (context->fds[0] >= 0) {
1355 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
1356 		if (ab) {
1357 			audit_log_format(ab, "fd0=%d fd1=%d",
1358 					context->fds[0], context->fds[1]);
1359 			audit_log_end(ab);
1360 		}
1361 	}
1362 
1363 	if (context->sockaddr_len) {
1364 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
1365 		if (ab) {
1366 			audit_log_format(ab, "saddr=");
1367 			audit_log_n_hex(ab, (void *)context->sockaddr,
1368 					context->sockaddr_len);
1369 			audit_log_end(ab);
1370 		}
1371 	}
1372 
1373 	for (aux = context->aux_pids; aux; aux = aux->next) {
1374 		struct audit_aux_data_pids *axs = (void *)aux;
1375 
1376 		for (i = 0; i < axs->pid_count; i++)
1377 			if (audit_log_pid_context(context, axs->target_pid[i],
1378 						  axs->target_auid[i],
1379 						  axs->target_uid[i],
1380 						  axs->target_sessionid[i],
1381 						  axs->target_sid[i],
1382 						  axs->target_comm[i]))
1383 				call_panic = 1;
1384 	}
1385 
1386 	if (context->target_pid &&
1387 	    audit_log_pid_context(context, context->target_pid,
1388 				  context->target_auid, context->target_uid,
1389 				  context->target_sessionid,
1390 				  context->target_sid, context->target_comm))
1391 			call_panic = 1;
1392 
1393 	if (context->pwd.dentry && context->pwd.mnt) {
1394 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1395 		if (ab) {
1396 			audit_log_d_path(ab, " cwd=", &context->pwd);
1397 			audit_log_end(ab);
1398 		}
1399 	}
1400 
1401 	i = 0;
1402 	list_for_each_entry(n, &context->names_list, list)
1403 		audit_log_name(context, n, NULL, i++, &call_panic);
1404 
1405 	/* Send end of event record to help user space know we are finished */
1406 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1407 	if (ab)
1408 		audit_log_end(ab);
1409 	if (call_panic)
1410 		audit_panic("error converting sid to string");
1411 }
1412 
1413 /**
1414  * audit_free - free a per-task audit context
1415  * @tsk: task whose audit context block to free
1416  *
1417  * Called from copy_process and do_exit
1418  */
1419 void __audit_free(struct task_struct *tsk)
1420 {
1421 	struct audit_context *context;
1422 
1423 	context = audit_get_context(tsk, 0, 0);
1424 	if (!context)
1425 		return;
1426 
1427 	/* Check for system calls that do not go through the exit
1428 	 * function (e.g., exit_group), then free context block.
1429 	 * We use GFP_ATOMIC here because we might be doing this
1430 	 * in the context of the idle thread */
1431 	/* that can happen only if we are called from do_exit() */
1432 	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1433 		audit_log_exit(context, tsk);
1434 	if (!list_empty(&context->killed_trees))
1435 		audit_kill_trees(&context->killed_trees);
1436 
1437 	audit_free_context(context);
1438 }
1439 
1440 /**
1441  * audit_syscall_entry - fill in an audit record at syscall entry
1442  * @arch: architecture type
1443  * @major: major syscall type (function)
1444  * @a1: additional syscall register 1
1445  * @a2: additional syscall register 2
1446  * @a3: additional syscall register 3
1447  * @a4: additional syscall register 4
1448  *
1449  * Fill in audit context at syscall entry.  This only happens if the
1450  * audit context was created when the task was created and the state or
1451  * filters demand the audit context be built.  If the state from the
1452  * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1453  * then the record will be written at syscall exit time (otherwise, it
1454  * will only be written if another part of the kernel requests that it
1455  * be written).
1456  */
1457 void __audit_syscall_entry(int arch, int major,
1458 			 unsigned long a1, unsigned long a2,
1459 			 unsigned long a3, unsigned long a4)
1460 {
1461 	struct task_struct *tsk = current;
1462 	struct audit_context *context = tsk->audit_context;
1463 	enum audit_state     state;
1464 
1465 	if (!context)
1466 		return;
1467 
1468 	BUG_ON(context->in_syscall || context->name_count);
1469 
1470 	if (!audit_enabled)
1471 		return;
1472 
1473 	context->arch	    = arch;
1474 	context->major      = major;
1475 	context->argv[0]    = a1;
1476 	context->argv[1]    = a2;
1477 	context->argv[2]    = a3;
1478 	context->argv[3]    = a4;
1479 
1480 	state = context->state;
1481 	context->dummy = !audit_n_rules;
1482 	if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
1483 		context->prio = 0;
1484 		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1485 	}
1486 	if (state == AUDIT_DISABLED)
1487 		return;
1488 
1489 	context->serial     = 0;
1490 	context->ctime      = CURRENT_TIME;
1491 	context->in_syscall = 1;
1492 	context->current_state  = state;
1493 	context->ppid       = 0;
1494 }
1495 
1496 /**
1497  * audit_syscall_exit - deallocate audit context after a system call
1498  * @success: success value of the syscall
1499  * @return_code: return value of the syscall
1500  *
1501  * Tear down after system call.  If the audit context has been marked as
1502  * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1503  * filtering, or because some other part of the kernel wrote an audit
1504  * message), then write out the syscall information.  In call cases,
1505  * free the names stored from getname().
1506  */
1507 void __audit_syscall_exit(int success, long return_code)
1508 {
1509 	struct task_struct *tsk = current;
1510 	struct audit_context *context;
1511 
1512 	if (success)
1513 		success = AUDITSC_SUCCESS;
1514 	else
1515 		success = AUDITSC_FAILURE;
1516 
1517 	context = audit_get_context(tsk, success, return_code);
1518 	if (!context)
1519 		return;
1520 
1521 	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1522 		audit_log_exit(context, tsk);
1523 
1524 	context->in_syscall = 0;
1525 	context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
1526 
1527 	if (!list_empty(&context->killed_trees))
1528 		audit_kill_trees(&context->killed_trees);
1529 
1530 	audit_free_names(context);
1531 	unroll_tree_refs(context, NULL, 0);
1532 	audit_free_aux(context);
1533 	context->aux = NULL;
1534 	context->aux_pids = NULL;
1535 	context->target_pid = 0;
1536 	context->target_sid = 0;
1537 	context->sockaddr_len = 0;
1538 	context->type = 0;
1539 	context->fds[0] = -1;
1540 	if (context->state != AUDIT_RECORD_CONTEXT) {
1541 		kfree(context->filterkey);
1542 		context->filterkey = NULL;
1543 	}
1544 	tsk->audit_context = context;
1545 }
1546 
1547 static inline void handle_one(const struct inode *inode)
1548 {
1549 #ifdef CONFIG_AUDIT_TREE
1550 	struct audit_context *context;
1551 	struct audit_tree_refs *p;
1552 	struct audit_chunk *chunk;
1553 	int count;
1554 	if (likely(hlist_empty(&inode->i_fsnotify_marks)))
1555 		return;
1556 	context = current->audit_context;
1557 	p = context->trees;
1558 	count = context->tree_count;
1559 	rcu_read_lock();
1560 	chunk = audit_tree_lookup(inode);
1561 	rcu_read_unlock();
1562 	if (!chunk)
1563 		return;
1564 	if (likely(put_tree_ref(context, chunk)))
1565 		return;
1566 	if (unlikely(!grow_tree_refs(context))) {
1567 		printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
1568 		audit_set_auditable(context);
1569 		audit_put_chunk(chunk);
1570 		unroll_tree_refs(context, p, count);
1571 		return;
1572 	}
1573 	put_tree_ref(context, chunk);
1574 #endif
1575 }
1576 
1577 static void handle_path(const struct dentry *dentry)
1578 {
1579 #ifdef CONFIG_AUDIT_TREE
1580 	struct audit_context *context;
1581 	struct audit_tree_refs *p;
1582 	const struct dentry *d, *parent;
1583 	struct audit_chunk *drop;
1584 	unsigned long seq;
1585 	int count;
1586 
1587 	context = current->audit_context;
1588 	p = context->trees;
1589 	count = context->tree_count;
1590 retry:
1591 	drop = NULL;
1592 	d = dentry;
1593 	rcu_read_lock();
1594 	seq = read_seqbegin(&rename_lock);
1595 	for(;;) {
1596 		struct inode *inode = d->d_inode;
1597 		if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) {
1598 			struct audit_chunk *chunk;
1599 			chunk = audit_tree_lookup(inode);
1600 			if (chunk) {
1601 				if (unlikely(!put_tree_ref(context, chunk))) {
1602 					drop = chunk;
1603 					break;
1604 				}
1605 			}
1606 		}
1607 		parent = d->d_parent;
1608 		if (parent == d)
1609 			break;
1610 		d = parent;
1611 	}
1612 	if (unlikely(read_seqretry(&rename_lock, seq) || drop)) {  /* in this order */
1613 		rcu_read_unlock();
1614 		if (!drop) {
1615 			/* just a race with rename */
1616 			unroll_tree_refs(context, p, count);
1617 			goto retry;
1618 		}
1619 		audit_put_chunk(drop);
1620 		if (grow_tree_refs(context)) {
1621 			/* OK, got more space */
1622 			unroll_tree_refs(context, p, count);
1623 			goto retry;
1624 		}
1625 		/* too bad */
1626 		printk(KERN_WARNING
1627 			"out of memory, audit has lost a tree reference\n");
1628 		unroll_tree_refs(context, p, count);
1629 		audit_set_auditable(context);
1630 		return;
1631 	}
1632 	rcu_read_unlock();
1633 #endif
1634 }
1635 
1636 static struct audit_names *audit_alloc_name(struct audit_context *context,
1637 						unsigned char type)
1638 {
1639 	struct audit_names *aname;
1640 
1641 	if (context->name_count < AUDIT_NAMES) {
1642 		aname = &context->preallocated_names[context->name_count];
1643 		memset(aname, 0, sizeof(*aname));
1644 	} else {
1645 		aname = kzalloc(sizeof(*aname), GFP_NOFS);
1646 		if (!aname)
1647 			return NULL;
1648 		aname->should_free = true;
1649 	}
1650 
1651 	aname->ino = (unsigned long)-1;
1652 	aname->type = type;
1653 	list_add_tail(&aname->list, &context->names_list);
1654 
1655 	context->name_count++;
1656 #if AUDIT_DEBUG
1657 	context->ino_count++;
1658 #endif
1659 	return aname;
1660 }
1661 
1662 /**
1663  * audit_reusename - fill out filename with info from existing entry
1664  * @uptr: userland ptr to pathname
1665  *
1666  * Search the audit_names list for the current audit context. If there is an
1667  * existing entry with a matching "uptr" then return the filename
1668  * associated with that audit_name. If not, return NULL.
1669  */
1670 struct filename *
1671 __audit_reusename(const __user char *uptr)
1672 {
1673 	struct audit_context *context = current->audit_context;
1674 	struct audit_names *n;
1675 
1676 	list_for_each_entry(n, &context->names_list, list) {
1677 		if (!n->name)
1678 			continue;
1679 		if (n->name->uptr == uptr)
1680 			return n->name;
1681 	}
1682 	return NULL;
1683 }
1684 
1685 /**
1686  * audit_getname - add a name to the list
1687  * @name: name to add
1688  *
1689  * Add a name to the list of audit names for this context.
1690  * Called from fs/namei.c:getname().
1691  */
1692 void __audit_getname(struct filename *name)
1693 {
1694 	struct audit_context *context = current->audit_context;
1695 	struct audit_names *n;
1696 
1697 	if (!context->in_syscall) {
1698 #if AUDIT_DEBUG == 2
1699 		printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
1700 		       __FILE__, __LINE__, context->serial, name);
1701 		dump_stack();
1702 #endif
1703 		return;
1704 	}
1705 
1706 #if AUDIT_DEBUG
1707 	/* The filename _must_ have a populated ->name */
1708 	BUG_ON(!name->name);
1709 #endif
1710 
1711 	n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
1712 	if (!n)
1713 		return;
1714 
1715 	n->name = name;
1716 	n->name_len = AUDIT_NAME_FULL;
1717 	n->name_put = true;
1718 	name->aname = n;
1719 
1720 	if (!context->pwd.dentry)
1721 		get_fs_pwd(current->fs, &context->pwd);
1722 }
1723 
1724 /* audit_putname - intercept a putname request
1725  * @name: name to intercept and delay for putname
1726  *
1727  * If we have stored the name from getname in the audit context,
1728  * then we delay the putname until syscall exit.
1729  * Called from include/linux/fs.h:putname().
1730  */
1731 void audit_putname(struct filename *name)
1732 {
1733 	struct audit_context *context = current->audit_context;
1734 
1735 	BUG_ON(!context);
1736 	if (!context->in_syscall) {
1737 #if AUDIT_DEBUG == 2
1738 		printk(KERN_ERR "%s:%d(:%d): final_putname(%p)\n",
1739 		       __FILE__, __LINE__, context->serial, name);
1740 		if (context->name_count) {
1741 			struct audit_names *n;
1742 			int i = 0;
1743 
1744 			list_for_each_entry(n, &context->names_list, list)
1745 				printk(KERN_ERR "name[%d] = %p = %s\n", i++,
1746 				       n->name, n->name->name ?: "(null)");
1747 			}
1748 #endif
1749 		final_putname(name);
1750 	}
1751 #if AUDIT_DEBUG
1752 	else {
1753 		++context->put_count;
1754 		if (context->put_count > context->name_count) {
1755 			printk(KERN_ERR "%s:%d(:%d): major=%d"
1756 			       " in_syscall=%d putname(%p) name_count=%d"
1757 			       " put_count=%d\n",
1758 			       __FILE__, __LINE__,
1759 			       context->serial, context->major,
1760 			       context->in_syscall, name->name,
1761 			       context->name_count, context->put_count);
1762 			dump_stack();
1763 		}
1764 	}
1765 #endif
1766 }
1767 
1768 /**
1769  * __audit_inode - store the inode and device from a lookup
1770  * @name: name being audited
1771  * @dentry: dentry being audited
1772  * @parent: does this dentry represent the parent?
1773  */
1774 void __audit_inode(struct filename *name, const struct dentry *dentry,
1775 		   unsigned int parent)
1776 {
1777 	struct audit_context *context = current->audit_context;
1778 	const struct inode *inode = dentry->d_inode;
1779 	struct audit_names *n;
1780 
1781 	if (!context->in_syscall)
1782 		return;
1783 
1784 	if (!name)
1785 		goto out_alloc;
1786 
1787 #if AUDIT_DEBUG
1788 	/* The struct filename _must_ have a populated ->name */
1789 	BUG_ON(!name->name);
1790 #endif
1791 	/*
1792 	 * If we have a pointer to an audit_names entry already, then we can
1793 	 * just use it directly if the type is correct.
1794 	 */
1795 	n = name->aname;
1796 	if (n) {
1797 		if (parent) {
1798 			if (n->type == AUDIT_TYPE_PARENT ||
1799 			    n->type == AUDIT_TYPE_UNKNOWN)
1800 				goto out;
1801 		} else {
1802 			if (n->type != AUDIT_TYPE_PARENT)
1803 				goto out;
1804 		}
1805 	}
1806 
1807 	list_for_each_entry_reverse(n, &context->names_list, list) {
1808 		/* does the name pointer match? */
1809 		if (!n->name || n->name->name != name->name)
1810 			continue;
1811 
1812 		/* match the correct record type */
1813 		if (parent) {
1814 			if (n->type == AUDIT_TYPE_PARENT ||
1815 			    n->type == AUDIT_TYPE_UNKNOWN)
1816 				goto out;
1817 		} else {
1818 			if (n->type != AUDIT_TYPE_PARENT)
1819 				goto out;
1820 		}
1821 	}
1822 
1823 out_alloc:
1824 	/* unable to find the name from a previous getname(). Allocate a new
1825 	 * anonymous entry.
1826 	 */
1827 	n = audit_alloc_name(context, AUDIT_TYPE_NORMAL);
1828 	if (!n)
1829 		return;
1830 out:
1831 	if (parent) {
1832 		n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL;
1833 		n->type = AUDIT_TYPE_PARENT;
1834 	} else {
1835 		n->name_len = AUDIT_NAME_FULL;
1836 		n->type = AUDIT_TYPE_NORMAL;
1837 	}
1838 	handle_path(dentry);
1839 	audit_copy_inode(n, dentry, inode);
1840 }
1841 
1842 /**
1843  * __audit_inode_child - collect inode info for created/removed objects
1844  * @parent: inode of dentry parent
1845  * @dentry: dentry being audited
1846  * @type:   AUDIT_TYPE_* value that we're looking for
1847  *
1848  * For syscalls that create or remove filesystem objects, audit_inode
1849  * can only collect information for the filesystem object's parent.
1850  * This call updates the audit context with the child's information.
1851  * Syscalls that create a new filesystem object must be hooked after
1852  * the object is created.  Syscalls that remove a filesystem object
1853  * must be hooked prior, in order to capture the target inode during
1854  * unsuccessful attempts.
1855  */
1856 void __audit_inode_child(const struct inode *parent,
1857 			 const struct dentry *dentry,
1858 			 const unsigned char type)
1859 {
1860 	struct audit_context *context = current->audit_context;
1861 	const struct inode *inode = dentry->d_inode;
1862 	const char *dname = dentry->d_name.name;
1863 	struct audit_names *n, *found_parent = NULL, *found_child = NULL;
1864 
1865 	if (!context->in_syscall)
1866 		return;
1867 
1868 	if (inode)
1869 		handle_one(inode);
1870 
1871 	/* look for a parent entry first */
1872 	list_for_each_entry(n, &context->names_list, list) {
1873 		if (!n->name || n->type != AUDIT_TYPE_PARENT)
1874 			continue;
1875 
1876 		if (n->ino == parent->i_ino &&
1877 		    !audit_compare_dname_path(dname, n->name->name, n->name_len)) {
1878 			found_parent = n;
1879 			break;
1880 		}
1881 	}
1882 
1883 	/* is there a matching child entry? */
1884 	list_for_each_entry(n, &context->names_list, list) {
1885 		/* can only match entries that have a name */
1886 		if (!n->name || n->type != type)
1887 			continue;
1888 
1889 		/* if we found a parent, make sure this one is a child of it */
1890 		if (found_parent && (n->name != found_parent->name))
1891 			continue;
1892 
1893 		if (!strcmp(dname, n->name->name) ||
1894 		    !audit_compare_dname_path(dname, n->name->name,
1895 						found_parent ?
1896 						found_parent->name_len :
1897 						AUDIT_NAME_FULL)) {
1898 			found_child = n;
1899 			break;
1900 		}
1901 	}
1902 
1903 	if (!found_parent) {
1904 		/* create a new, "anonymous" parent record */
1905 		n = audit_alloc_name(context, AUDIT_TYPE_PARENT);
1906 		if (!n)
1907 			return;
1908 		audit_copy_inode(n, NULL, parent);
1909 	}
1910 
1911 	if (!found_child) {
1912 		found_child = audit_alloc_name(context, type);
1913 		if (!found_child)
1914 			return;
1915 
1916 		/* Re-use the name belonging to the slot for a matching parent
1917 		 * directory. All names for this context are relinquished in
1918 		 * audit_free_names() */
1919 		if (found_parent) {
1920 			found_child->name = found_parent->name;
1921 			found_child->name_len = AUDIT_NAME_FULL;
1922 			/* don't call __putname() */
1923 			found_child->name_put = false;
1924 		}
1925 	}
1926 	if (inode)
1927 		audit_copy_inode(found_child, dentry, inode);
1928 	else
1929 		found_child->ino = (unsigned long)-1;
1930 }
1931 EXPORT_SYMBOL_GPL(__audit_inode_child);
1932 
1933 /**
1934  * auditsc_get_stamp - get local copies of audit_context values
1935  * @ctx: audit_context for the task
1936  * @t: timespec to store time recorded in the audit_context
1937  * @serial: serial value that is recorded in the audit_context
1938  *
1939  * Also sets the context as auditable.
1940  */
1941 int auditsc_get_stamp(struct audit_context *ctx,
1942 		       struct timespec *t, unsigned int *serial)
1943 {
1944 	if (!ctx->in_syscall)
1945 		return 0;
1946 	if (!ctx->serial)
1947 		ctx->serial = audit_serial();
1948 	t->tv_sec  = ctx->ctime.tv_sec;
1949 	t->tv_nsec = ctx->ctime.tv_nsec;
1950 	*serial    = ctx->serial;
1951 	if (!ctx->prio) {
1952 		ctx->prio = 1;
1953 		ctx->current_state = AUDIT_RECORD_CONTEXT;
1954 	}
1955 	return 1;
1956 }
1957 
1958 /* global counter which is incremented every time something logs in */
1959 static atomic_t session_id = ATOMIC_INIT(0);
1960 
1961 /**
1962  * audit_set_loginuid - set current task's audit_context loginuid
1963  * @loginuid: loginuid value
1964  *
1965  * Returns 0.
1966  *
1967  * Called (set) from fs/proc/base.c::proc_loginuid_write().
1968  */
1969 int audit_set_loginuid(kuid_t loginuid)
1970 {
1971 	struct task_struct *task = current;
1972 	struct audit_context *context = task->audit_context;
1973 	unsigned int sessionid;
1974 
1975 #ifdef CONFIG_AUDIT_LOGINUID_IMMUTABLE
1976 	if (audit_loginuid_set(task))
1977 		return -EPERM;
1978 #else /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */
1979 	if (!capable(CAP_AUDIT_CONTROL))
1980 		return -EPERM;
1981 #endif  /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */
1982 
1983 	sessionid = atomic_inc_return(&session_id);
1984 	if (context && context->in_syscall) {
1985 		struct audit_buffer *ab;
1986 
1987 		ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
1988 		if (ab) {
1989 			audit_log_format(ab, "login pid=%d uid=%u "
1990 				"old auid=%u new auid=%u"
1991 				" old ses=%u new ses=%u",
1992 				task->pid,
1993 				from_kuid(&init_user_ns, task_uid(task)),
1994 				from_kuid(&init_user_ns, task->loginuid),
1995 				from_kuid(&init_user_ns, loginuid),
1996 				task->sessionid, sessionid);
1997 			audit_log_end(ab);
1998 		}
1999 	}
2000 	task->sessionid = sessionid;
2001 	task->loginuid = loginuid;
2002 	return 0;
2003 }
2004 
2005 /**
2006  * __audit_mq_open - record audit data for a POSIX MQ open
2007  * @oflag: open flag
2008  * @mode: mode bits
2009  * @attr: queue attributes
2010  *
2011  */
2012 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
2013 {
2014 	struct audit_context *context = current->audit_context;
2015 
2016 	if (attr)
2017 		memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
2018 	else
2019 		memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2020 
2021 	context->mq_open.oflag = oflag;
2022 	context->mq_open.mode = mode;
2023 
2024 	context->type = AUDIT_MQ_OPEN;
2025 }
2026 
2027 /**
2028  * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2029  * @mqdes: MQ descriptor
2030  * @msg_len: Message length
2031  * @msg_prio: Message priority
2032  * @abs_timeout: Message timeout in absolute time
2033  *
2034  */
2035 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2036 			const struct timespec *abs_timeout)
2037 {
2038 	struct audit_context *context = current->audit_context;
2039 	struct timespec *p = &context->mq_sendrecv.abs_timeout;
2040 
2041 	if (abs_timeout)
2042 		memcpy(p, abs_timeout, sizeof(struct timespec));
2043 	else
2044 		memset(p, 0, sizeof(struct timespec));
2045 
2046 	context->mq_sendrecv.mqdes = mqdes;
2047 	context->mq_sendrecv.msg_len = msg_len;
2048 	context->mq_sendrecv.msg_prio = msg_prio;
2049 
2050 	context->type = AUDIT_MQ_SENDRECV;
2051 }
2052 
2053 /**
2054  * __audit_mq_notify - record audit data for a POSIX MQ notify
2055  * @mqdes: MQ descriptor
2056  * @notification: Notification event
2057  *
2058  */
2059 
2060 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2061 {
2062 	struct audit_context *context = current->audit_context;
2063 
2064 	if (notification)
2065 		context->mq_notify.sigev_signo = notification->sigev_signo;
2066 	else
2067 		context->mq_notify.sigev_signo = 0;
2068 
2069 	context->mq_notify.mqdes = mqdes;
2070 	context->type = AUDIT_MQ_NOTIFY;
2071 }
2072 
2073 /**
2074  * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2075  * @mqdes: MQ descriptor
2076  * @mqstat: MQ flags
2077  *
2078  */
2079 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2080 {
2081 	struct audit_context *context = current->audit_context;
2082 	context->mq_getsetattr.mqdes = mqdes;
2083 	context->mq_getsetattr.mqstat = *mqstat;
2084 	context->type = AUDIT_MQ_GETSETATTR;
2085 }
2086 
2087 /**
2088  * audit_ipc_obj - record audit data for ipc object
2089  * @ipcp: ipc permissions
2090  *
2091  */
2092 void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2093 {
2094 	struct audit_context *context = current->audit_context;
2095 	context->ipc.uid = ipcp->uid;
2096 	context->ipc.gid = ipcp->gid;
2097 	context->ipc.mode = ipcp->mode;
2098 	context->ipc.has_perm = 0;
2099 	security_ipc_getsecid(ipcp, &context->ipc.osid);
2100 	context->type = AUDIT_IPC;
2101 }
2102 
2103 /**
2104  * audit_ipc_set_perm - record audit data for new ipc permissions
2105  * @qbytes: msgq bytes
2106  * @uid: msgq user id
2107  * @gid: msgq group id
2108  * @mode: msgq mode (permissions)
2109  *
2110  * Called only after audit_ipc_obj().
2111  */
2112 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
2113 {
2114 	struct audit_context *context = current->audit_context;
2115 
2116 	context->ipc.qbytes = qbytes;
2117 	context->ipc.perm_uid = uid;
2118 	context->ipc.perm_gid = gid;
2119 	context->ipc.perm_mode = mode;
2120 	context->ipc.has_perm = 1;
2121 }
2122 
2123 int __audit_bprm(struct linux_binprm *bprm)
2124 {
2125 	struct audit_aux_data_execve *ax;
2126 	struct audit_context *context = current->audit_context;
2127 
2128 	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2129 	if (!ax)
2130 		return -ENOMEM;
2131 
2132 	ax->argc = bprm->argc;
2133 	ax->envc = bprm->envc;
2134 	ax->mm = bprm->mm;
2135 	ax->d.type = AUDIT_EXECVE;
2136 	ax->d.next = context->aux;
2137 	context->aux = (void *)ax;
2138 	return 0;
2139 }
2140 
2141 
2142 /**
2143  * audit_socketcall - record audit data for sys_socketcall
2144  * @nargs: number of args, which should not be more than AUDITSC_ARGS.
2145  * @args: args array
2146  *
2147  */
2148 int __audit_socketcall(int nargs, unsigned long *args)
2149 {
2150 	struct audit_context *context = current->audit_context;
2151 
2152 	if (nargs <= 0 || nargs > AUDITSC_ARGS || !args)
2153 		return -EINVAL;
2154 	context->type = AUDIT_SOCKETCALL;
2155 	context->socketcall.nargs = nargs;
2156 	memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
2157 	return 0;
2158 }
2159 
2160 /**
2161  * __audit_fd_pair - record audit data for pipe and socketpair
2162  * @fd1: the first file descriptor
2163  * @fd2: the second file descriptor
2164  *
2165  */
2166 void __audit_fd_pair(int fd1, int fd2)
2167 {
2168 	struct audit_context *context = current->audit_context;
2169 	context->fds[0] = fd1;
2170 	context->fds[1] = fd2;
2171 }
2172 
2173 /**
2174  * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2175  * @len: data length in user space
2176  * @a: data address in kernel space
2177  *
2178  * Returns 0 for success or NULL context or < 0 on error.
2179  */
2180 int __audit_sockaddr(int len, void *a)
2181 {
2182 	struct audit_context *context = current->audit_context;
2183 
2184 	if (!context->sockaddr) {
2185 		void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
2186 		if (!p)
2187 			return -ENOMEM;
2188 		context->sockaddr = p;
2189 	}
2190 
2191 	context->sockaddr_len = len;
2192 	memcpy(context->sockaddr, a, len);
2193 	return 0;
2194 }
2195 
2196 void __audit_ptrace(struct task_struct *t)
2197 {
2198 	struct audit_context *context = current->audit_context;
2199 
2200 	context->target_pid = t->pid;
2201 	context->target_auid = audit_get_loginuid(t);
2202 	context->target_uid = task_uid(t);
2203 	context->target_sessionid = audit_get_sessionid(t);
2204 	security_task_getsecid(t, &context->target_sid);
2205 	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
2206 }
2207 
2208 /**
2209  * audit_signal_info - record signal info for shutting down audit subsystem
2210  * @sig: signal value
2211  * @t: task being signaled
2212  *
2213  * If the audit subsystem is being terminated, record the task (pid)
2214  * and uid that is doing that.
2215  */
2216 int __audit_signal_info(int sig, struct task_struct *t)
2217 {
2218 	struct audit_aux_data_pids *axp;
2219 	struct task_struct *tsk = current;
2220 	struct audit_context *ctx = tsk->audit_context;
2221 	kuid_t uid = current_uid(), t_uid = task_uid(t);
2222 
2223 	if (audit_pid && t->tgid == audit_pid) {
2224 		if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
2225 			audit_sig_pid = tsk->pid;
2226 			if (uid_valid(tsk->loginuid))
2227 				audit_sig_uid = tsk->loginuid;
2228 			else
2229 				audit_sig_uid = uid;
2230 			security_task_getsecid(tsk, &audit_sig_sid);
2231 		}
2232 		if (!audit_signals || audit_dummy_context())
2233 			return 0;
2234 	}
2235 
2236 	/* optimize the common case by putting first signal recipient directly
2237 	 * in audit_context */
2238 	if (!ctx->target_pid) {
2239 		ctx->target_pid = t->tgid;
2240 		ctx->target_auid = audit_get_loginuid(t);
2241 		ctx->target_uid = t_uid;
2242 		ctx->target_sessionid = audit_get_sessionid(t);
2243 		security_task_getsecid(t, &ctx->target_sid);
2244 		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
2245 		return 0;
2246 	}
2247 
2248 	axp = (void *)ctx->aux_pids;
2249 	if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2250 		axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2251 		if (!axp)
2252 			return -ENOMEM;
2253 
2254 		axp->d.type = AUDIT_OBJ_PID;
2255 		axp->d.next = ctx->aux_pids;
2256 		ctx->aux_pids = (void *)axp;
2257 	}
2258 	BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2259 
2260 	axp->target_pid[axp->pid_count] = t->tgid;
2261 	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2262 	axp->target_uid[axp->pid_count] = t_uid;
2263 	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2264 	security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2265 	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
2266 	axp->pid_count++;
2267 
2268 	return 0;
2269 }
2270 
2271 /**
2272  * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
2273  * @bprm: pointer to the bprm being processed
2274  * @new: the proposed new credentials
2275  * @old: the old credentials
2276  *
2277  * Simply check if the proc already has the caps given by the file and if not
2278  * store the priv escalation info for later auditing at the end of the syscall
2279  *
2280  * -Eric
2281  */
2282 int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
2283 			   const struct cred *new, const struct cred *old)
2284 {
2285 	struct audit_aux_data_bprm_fcaps *ax;
2286 	struct audit_context *context = current->audit_context;
2287 	struct cpu_vfs_cap_data vcaps;
2288 	struct dentry *dentry;
2289 
2290 	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2291 	if (!ax)
2292 		return -ENOMEM;
2293 
2294 	ax->d.type = AUDIT_BPRM_FCAPS;
2295 	ax->d.next = context->aux;
2296 	context->aux = (void *)ax;
2297 
2298 	dentry = dget(bprm->file->f_dentry);
2299 	get_vfs_caps_from_disk(dentry, &vcaps);
2300 	dput(dentry);
2301 
2302 	ax->fcap.permitted = vcaps.permitted;
2303 	ax->fcap.inheritable = vcaps.inheritable;
2304 	ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2305 	ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
2306 
2307 	ax->old_pcap.permitted   = old->cap_permitted;
2308 	ax->old_pcap.inheritable = old->cap_inheritable;
2309 	ax->old_pcap.effective   = old->cap_effective;
2310 
2311 	ax->new_pcap.permitted   = new->cap_permitted;
2312 	ax->new_pcap.inheritable = new->cap_inheritable;
2313 	ax->new_pcap.effective   = new->cap_effective;
2314 	return 0;
2315 }
2316 
2317 /**
2318  * __audit_log_capset - store information about the arguments to the capset syscall
2319  * @pid: target pid of the capset call
2320  * @new: the new credentials
2321  * @old: the old (current) credentials
2322  *
2323  * Record the aguments userspace sent to sys_capset for later printing by the
2324  * audit system if applicable
2325  */
2326 void __audit_log_capset(pid_t pid,
2327 		       const struct cred *new, const struct cred *old)
2328 {
2329 	struct audit_context *context = current->audit_context;
2330 	context->capset.pid = pid;
2331 	context->capset.cap.effective   = new->cap_effective;
2332 	context->capset.cap.inheritable = new->cap_effective;
2333 	context->capset.cap.permitted   = new->cap_permitted;
2334 	context->type = AUDIT_CAPSET;
2335 }
2336 
2337 void __audit_mmap_fd(int fd, int flags)
2338 {
2339 	struct audit_context *context = current->audit_context;
2340 	context->mmap.fd = fd;
2341 	context->mmap.flags = flags;
2342 	context->type = AUDIT_MMAP;
2343 }
2344 
2345 static void audit_log_task(struct audit_buffer *ab)
2346 {
2347 	kuid_t auid, uid;
2348 	kgid_t gid;
2349 	unsigned int sessionid;
2350 
2351 	auid = audit_get_loginuid(current);
2352 	sessionid = audit_get_sessionid(current);
2353 	current_uid_gid(&uid, &gid);
2354 
2355 	audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2356 			 from_kuid(&init_user_ns, auid),
2357 			 from_kuid(&init_user_ns, uid),
2358 			 from_kgid(&init_user_ns, gid),
2359 			 sessionid);
2360 	audit_log_task_context(ab);
2361 	audit_log_format(ab, " pid=%d comm=", current->pid);
2362 	audit_log_untrustedstring(ab, current->comm);
2363 }
2364 
2365 static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
2366 {
2367 	audit_log_task(ab);
2368 	audit_log_format(ab, " reason=");
2369 	audit_log_string(ab, reason);
2370 	audit_log_format(ab, " sig=%ld", signr);
2371 }
2372 /**
2373  * audit_core_dumps - record information about processes that end abnormally
2374  * @signr: signal value
2375  *
2376  * If a process ends with a core dump, something fishy is going on and we
2377  * should record the event for investigation.
2378  */
2379 void audit_core_dumps(long signr)
2380 {
2381 	struct audit_buffer *ab;
2382 
2383 	if (!audit_enabled)
2384 		return;
2385 
2386 	if (signr == SIGQUIT)	/* don't care for those */
2387 		return;
2388 
2389 	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2390 	if (unlikely(!ab))
2391 		return;
2392 	audit_log_abend(ab, "memory violation", signr);
2393 	audit_log_end(ab);
2394 }
2395 
2396 void __audit_seccomp(unsigned long syscall, long signr, int code)
2397 {
2398 	struct audit_buffer *ab;
2399 
2400 	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_SECCOMP);
2401 	if (unlikely(!ab))
2402 		return;
2403 	audit_log_task(ab);
2404 	audit_log_format(ab, " sig=%ld", signr);
2405 	audit_log_format(ab, " syscall=%ld", syscall);
2406 	audit_log_format(ab, " compat=%d", is_compat_task());
2407 	audit_log_format(ab, " ip=0x%lx", KSTK_EIP(current));
2408 	audit_log_format(ab, " code=0x%x", code);
2409 	audit_log_end(ab);
2410 }
2411 
2412 struct list_head *audit_killed_trees(void)
2413 {
2414 	struct audit_context *ctx = current->audit_context;
2415 	if (likely(!ctx || !ctx->in_syscall))
2416 		return NULL;
2417 	return &ctx->killed_trees;
2418 }
2419