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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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
46 
47 #include <linux/init.h>
48 #include <asm/types.h>
49 #include <linux/atomic.h>
50 #include <linux/fs.h>
51 #include <linux/namei.h>
52 #include <linux/mm.h>
53 #include <linux/export.h>
54 #include <linux/slab.h>
55 #include <linux/mount.h>
56 #include <linux/socket.h>
57 #include <linux/mqueue.h>
58 #include <linux/audit.h>
59 #include <linux/personality.h>
60 #include <linux/time.h>
61 #include <linux/netlink.h>
62 #include <linux/compiler.h>
63 #include <asm/unistd.h>
64 #include <linux/security.h>
65 #include <linux/list.h>
66 #include <linux/binfmts.h>
67 #include <linux/highmem.h>
68 #include <linux/syscalls.h>
69 #include <asm/syscall.h>
70 #include <linux/capability.h>
71 #include <linux/fs_struct.h>
72 #include <linux/compat.h>
73 #include <linux/ctype.h>
74 #include <linux/string.h>
75 #include <linux/uaccess.h>
76 #include <linux/fsnotify_backend.h>
77 #include <uapi/linux/limits.h>
78 
79 #include "audit.h"
80 
81 /* flags stating the success for a syscall */
82 #define AUDITSC_INVALID 0
83 #define AUDITSC_SUCCESS 1
84 #define AUDITSC_FAILURE 2
85 
86 /* no execve audit message should be longer than this (userspace limits),
87  * see the note near the top of audit_log_execve_info() about this value */
88 #define MAX_EXECVE_AUDIT_LEN 7500
89 
90 /* max length to print of cmdline/proctitle value during audit */
91 #define MAX_PROCTITLE_AUDIT_LEN 128
92 
93 /* number of audit rules */
94 int audit_n_rules;
95 
96 /* determines whether we collect data for signals sent */
97 int audit_signals;
98 
99 struct audit_aux_data {
100 	struct audit_aux_data	*next;
101 	int			type;
102 };
103 
104 #define AUDIT_AUX_IPCPERM	0
105 
106 /* Number of target pids per aux struct. */
107 #define AUDIT_AUX_PIDS	16
108 
109 struct audit_aux_data_pids {
110 	struct audit_aux_data	d;
111 	pid_t			target_pid[AUDIT_AUX_PIDS];
112 	kuid_t			target_auid[AUDIT_AUX_PIDS];
113 	kuid_t			target_uid[AUDIT_AUX_PIDS];
114 	unsigned int		target_sessionid[AUDIT_AUX_PIDS];
115 	u32			target_sid[AUDIT_AUX_PIDS];
116 	char 			target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
117 	int			pid_count;
118 };
119 
120 struct audit_aux_data_bprm_fcaps {
121 	struct audit_aux_data	d;
122 	struct audit_cap_data	fcap;
123 	unsigned int		fcap_ver;
124 	struct audit_cap_data	old_pcap;
125 	struct audit_cap_data	new_pcap;
126 };
127 
128 struct audit_tree_refs {
129 	struct audit_tree_refs *next;
130 	struct audit_chunk *c[31];
131 };
132 
audit_match_perm(struct audit_context * ctx,int mask)133 static int audit_match_perm(struct audit_context *ctx, int mask)
134 {
135 	unsigned n;
136 	if (unlikely(!ctx))
137 		return 0;
138 	n = ctx->major;
139 
140 	switch (audit_classify_syscall(ctx->arch, n)) {
141 	case 0:	/* native */
142 		if ((mask & AUDIT_PERM_WRITE) &&
143 		     audit_match_class(AUDIT_CLASS_WRITE, n))
144 			return 1;
145 		if ((mask & AUDIT_PERM_READ) &&
146 		     audit_match_class(AUDIT_CLASS_READ, n))
147 			return 1;
148 		if ((mask & AUDIT_PERM_ATTR) &&
149 		     audit_match_class(AUDIT_CLASS_CHATTR, n))
150 			return 1;
151 		return 0;
152 	case 1: /* 32bit on biarch */
153 		if ((mask & AUDIT_PERM_WRITE) &&
154 		     audit_match_class(AUDIT_CLASS_WRITE_32, n))
155 			return 1;
156 		if ((mask & AUDIT_PERM_READ) &&
157 		     audit_match_class(AUDIT_CLASS_READ_32, n))
158 			return 1;
159 		if ((mask & AUDIT_PERM_ATTR) &&
160 		     audit_match_class(AUDIT_CLASS_CHATTR_32, n))
161 			return 1;
162 		return 0;
163 	case 2: /* open */
164 		return mask & ACC_MODE(ctx->argv[1]);
165 	case 3: /* openat */
166 		return mask & ACC_MODE(ctx->argv[2]);
167 	case 4: /* socketcall */
168 		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
169 	case 5: /* execve */
170 		return mask & AUDIT_PERM_EXEC;
171 	default:
172 		return 0;
173 	}
174 }
175 
audit_match_filetype(struct audit_context * ctx,int val)176 static int audit_match_filetype(struct audit_context *ctx, int val)
177 {
178 	struct audit_names *n;
179 	umode_t mode = (umode_t)val;
180 
181 	if (unlikely(!ctx))
182 		return 0;
183 
184 	list_for_each_entry(n, &ctx->names_list, list) {
185 		if ((n->ino != AUDIT_INO_UNSET) &&
186 		    ((n->mode & S_IFMT) == mode))
187 			return 1;
188 	}
189 
190 	return 0;
191 }
192 
193 /*
194  * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
195  * ->first_trees points to its beginning, ->trees - to the current end of data.
196  * ->tree_count is the number of free entries in array pointed to by ->trees.
197  * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
198  * "empty" becomes (p, p, 31) afterwards.  We don't shrink the list (and seriously,
199  * it's going to remain 1-element for almost any setup) until we free context itself.
200  * References in it _are_ dropped - at the same time we free/drop aux stuff.
201  */
202 
audit_set_auditable(struct audit_context * ctx)203 static void audit_set_auditable(struct audit_context *ctx)
204 {
205 	if (!ctx->prio) {
206 		ctx->prio = 1;
207 		ctx->current_state = AUDIT_RECORD_CONTEXT;
208 	}
209 }
210 
put_tree_ref(struct audit_context * ctx,struct audit_chunk * chunk)211 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
212 {
213 	struct audit_tree_refs *p = ctx->trees;
214 	int left = ctx->tree_count;
215 	if (likely(left)) {
216 		p->c[--left] = chunk;
217 		ctx->tree_count = left;
218 		return 1;
219 	}
220 	if (!p)
221 		return 0;
222 	p = p->next;
223 	if (p) {
224 		p->c[30] = chunk;
225 		ctx->trees = p;
226 		ctx->tree_count = 30;
227 		return 1;
228 	}
229 	return 0;
230 }
231 
grow_tree_refs(struct audit_context * ctx)232 static int grow_tree_refs(struct audit_context *ctx)
233 {
234 	struct audit_tree_refs *p = ctx->trees;
235 	ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
236 	if (!ctx->trees) {
237 		ctx->trees = p;
238 		return 0;
239 	}
240 	if (p)
241 		p->next = ctx->trees;
242 	else
243 		ctx->first_trees = ctx->trees;
244 	ctx->tree_count = 31;
245 	return 1;
246 }
247 
unroll_tree_refs(struct audit_context * ctx,struct audit_tree_refs * p,int count)248 static void unroll_tree_refs(struct audit_context *ctx,
249 		      struct audit_tree_refs *p, int count)
250 {
251 	struct audit_tree_refs *q;
252 	int n;
253 	if (!p) {
254 		/* we started with empty chain */
255 		p = ctx->first_trees;
256 		count = 31;
257 		/* if the very first allocation has failed, nothing to do */
258 		if (!p)
259 			return;
260 	}
261 	n = count;
262 	for (q = p; q != ctx->trees; q = q->next, n = 31) {
263 		while (n--) {
264 			audit_put_chunk(q->c[n]);
265 			q->c[n] = NULL;
266 		}
267 	}
268 	while (n-- > ctx->tree_count) {
269 		audit_put_chunk(q->c[n]);
270 		q->c[n] = NULL;
271 	}
272 	ctx->trees = p;
273 	ctx->tree_count = count;
274 }
275 
free_tree_refs(struct audit_context * ctx)276 static void free_tree_refs(struct audit_context *ctx)
277 {
278 	struct audit_tree_refs *p, *q;
279 	for (p = ctx->first_trees; p; p = q) {
280 		q = p->next;
281 		kfree(p);
282 	}
283 }
284 
match_tree_refs(struct audit_context * ctx,struct audit_tree * tree)285 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
286 {
287 	struct audit_tree_refs *p;
288 	int n;
289 	if (!tree)
290 		return 0;
291 	/* full ones */
292 	for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
293 		for (n = 0; n < 31; n++)
294 			if (audit_tree_match(p->c[n], tree))
295 				return 1;
296 	}
297 	/* partial */
298 	if (p) {
299 		for (n = ctx->tree_count; n < 31; n++)
300 			if (audit_tree_match(p->c[n], tree))
301 				return 1;
302 	}
303 	return 0;
304 }
305 
audit_compare_uid(kuid_t uid,struct audit_names * name,struct audit_field * f,struct audit_context * ctx)306 static int audit_compare_uid(kuid_t uid,
307 			     struct audit_names *name,
308 			     struct audit_field *f,
309 			     struct audit_context *ctx)
310 {
311 	struct audit_names *n;
312 	int rc;
313 
314 	if (name) {
315 		rc = audit_uid_comparator(uid, f->op, name->uid);
316 		if (rc)
317 			return rc;
318 	}
319 
320 	if (ctx) {
321 		list_for_each_entry(n, &ctx->names_list, list) {
322 			rc = audit_uid_comparator(uid, f->op, n->uid);
323 			if (rc)
324 				return rc;
325 		}
326 	}
327 	return 0;
328 }
329 
audit_compare_gid(kgid_t gid,struct audit_names * name,struct audit_field * f,struct audit_context * ctx)330 static int audit_compare_gid(kgid_t gid,
331 			     struct audit_names *name,
332 			     struct audit_field *f,
333 			     struct audit_context *ctx)
334 {
335 	struct audit_names *n;
336 	int rc;
337 
338 	if (name) {
339 		rc = audit_gid_comparator(gid, f->op, name->gid);
340 		if (rc)
341 			return rc;
342 	}
343 
344 	if (ctx) {
345 		list_for_each_entry(n, &ctx->names_list, list) {
346 			rc = audit_gid_comparator(gid, f->op, n->gid);
347 			if (rc)
348 				return rc;
349 		}
350 	}
351 	return 0;
352 }
353 
audit_field_compare(struct task_struct * tsk,const struct cred * cred,struct audit_field * f,struct audit_context * ctx,struct audit_names * name)354 static int audit_field_compare(struct task_struct *tsk,
355 			       const struct cred *cred,
356 			       struct audit_field *f,
357 			       struct audit_context *ctx,
358 			       struct audit_names *name)
359 {
360 	switch (f->val) {
361 	/* process to file object comparisons */
362 	case AUDIT_COMPARE_UID_TO_OBJ_UID:
363 		return audit_compare_uid(cred->uid, name, f, ctx);
364 	case AUDIT_COMPARE_GID_TO_OBJ_GID:
365 		return audit_compare_gid(cred->gid, name, f, ctx);
366 	case AUDIT_COMPARE_EUID_TO_OBJ_UID:
367 		return audit_compare_uid(cred->euid, name, f, ctx);
368 	case AUDIT_COMPARE_EGID_TO_OBJ_GID:
369 		return audit_compare_gid(cred->egid, name, f, ctx);
370 	case AUDIT_COMPARE_AUID_TO_OBJ_UID:
371 		return audit_compare_uid(audit_get_loginuid(tsk), name, f, ctx);
372 	case AUDIT_COMPARE_SUID_TO_OBJ_UID:
373 		return audit_compare_uid(cred->suid, name, f, ctx);
374 	case AUDIT_COMPARE_SGID_TO_OBJ_GID:
375 		return audit_compare_gid(cred->sgid, name, f, ctx);
376 	case AUDIT_COMPARE_FSUID_TO_OBJ_UID:
377 		return audit_compare_uid(cred->fsuid, name, f, ctx);
378 	case AUDIT_COMPARE_FSGID_TO_OBJ_GID:
379 		return audit_compare_gid(cred->fsgid, name, f, ctx);
380 	/* uid comparisons */
381 	case AUDIT_COMPARE_UID_TO_AUID:
382 		return audit_uid_comparator(cred->uid, f->op,
383 					    audit_get_loginuid(tsk));
384 	case AUDIT_COMPARE_UID_TO_EUID:
385 		return audit_uid_comparator(cred->uid, f->op, cred->euid);
386 	case AUDIT_COMPARE_UID_TO_SUID:
387 		return audit_uid_comparator(cred->uid, f->op, cred->suid);
388 	case AUDIT_COMPARE_UID_TO_FSUID:
389 		return audit_uid_comparator(cred->uid, f->op, cred->fsuid);
390 	/* auid comparisons */
391 	case AUDIT_COMPARE_AUID_TO_EUID:
392 		return audit_uid_comparator(audit_get_loginuid(tsk), f->op,
393 					    cred->euid);
394 	case AUDIT_COMPARE_AUID_TO_SUID:
395 		return audit_uid_comparator(audit_get_loginuid(tsk), f->op,
396 					    cred->suid);
397 	case AUDIT_COMPARE_AUID_TO_FSUID:
398 		return audit_uid_comparator(audit_get_loginuid(tsk), f->op,
399 					    cred->fsuid);
400 	/* euid comparisons */
401 	case AUDIT_COMPARE_EUID_TO_SUID:
402 		return audit_uid_comparator(cred->euid, f->op, cred->suid);
403 	case AUDIT_COMPARE_EUID_TO_FSUID:
404 		return audit_uid_comparator(cred->euid, f->op, cred->fsuid);
405 	/* suid comparisons */
406 	case AUDIT_COMPARE_SUID_TO_FSUID:
407 		return audit_uid_comparator(cred->suid, f->op, cred->fsuid);
408 	/* gid comparisons */
409 	case AUDIT_COMPARE_GID_TO_EGID:
410 		return audit_gid_comparator(cred->gid, f->op, cred->egid);
411 	case AUDIT_COMPARE_GID_TO_SGID:
412 		return audit_gid_comparator(cred->gid, f->op, cred->sgid);
413 	case AUDIT_COMPARE_GID_TO_FSGID:
414 		return audit_gid_comparator(cred->gid, f->op, cred->fsgid);
415 	/* egid comparisons */
416 	case AUDIT_COMPARE_EGID_TO_SGID:
417 		return audit_gid_comparator(cred->egid, f->op, cred->sgid);
418 	case AUDIT_COMPARE_EGID_TO_FSGID:
419 		return audit_gid_comparator(cred->egid, f->op, cred->fsgid);
420 	/* sgid comparison */
421 	case AUDIT_COMPARE_SGID_TO_FSGID:
422 		return audit_gid_comparator(cred->sgid, f->op, cred->fsgid);
423 	default:
424 		WARN(1, "Missing AUDIT_COMPARE define.  Report as a bug\n");
425 		return 0;
426 	}
427 	return 0;
428 }
429 
430 /* Determine if any context name data matches a rule's watch data */
431 /* Compare a task_struct with an audit_rule.  Return 1 on match, 0
432  * otherwise.
433  *
434  * If task_creation is true, this is an explicit indication that we are
435  * filtering a task rule at task creation time.  This and tsk == current are
436  * the only situations where tsk->cred may be accessed without an rcu read lock.
437  */
audit_filter_rules(struct task_struct * tsk,struct audit_krule * rule,struct audit_context * ctx,struct audit_names * name,enum audit_state * state,bool task_creation)438 static int audit_filter_rules(struct task_struct *tsk,
439 			      struct audit_krule *rule,
440 			      struct audit_context *ctx,
441 			      struct audit_names *name,
442 			      enum audit_state *state,
443 			      bool task_creation)
444 {
445 	const struct cred *cred;
446 	int i, need_sid = 1;
447 	u32 sid;
448 	unsigned int sessionid;
449 
450 	cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);
451 
452 	for (i = 0; i < rule->field_count; i++) {
453 		struct audit_field *f = &rule->fields[i];
454 		struct audit_names *n;
455 		int result = 0;
456 		pid_t pid;
457 
458 		switch (f->type) {
459 		case AUDIT_PID:
460 			pid = task_tgid_nr(tsk);
461 			result = audit_comparator(pid, f->op, f->val);
462 			break;
463 		case AUDIT_PPID:
464 			if (ctx) {
465 				if (!ctx->ppid)
466 					ctx->ppid = task_ppid_nr(tsk);
467 				result = audit_comparator(ctx->ppid, f->op, f->val);
468 			}
469 			break;
470 		case AUDIT_EXE:
471 			result = audit_exe_compare(tsk, rule->exe);
472 			if (f->op == Audit_not_equal)
473 				result = !result;
474 			break;
475 		case AUDIT_UID:
476 			result = audit_uid_comparator(cred->uid, f->op, f->uid);
477 			break;
478 		case AUDIT_EUID:
479 			result = audit_uid_comparator(cred->euid, f->op, f->uid);
480 			break;
481 		case AUDIT_SUID:
482 			result = audit_uid_comparator(cred->suid, f->op, f->uid);
483 			break;
484 		case AUDIT_FSUID:
485 			result = audit_uid_comparator(cred->fsuid, f->op, f->uid);
486 			break;
487 		case AUDIT_GID:
488 			result = audit_gid_comparator(cred->gid, f->op, f->gid);
489 			if (f->op == Audit_equal) {
490 				if (!result)
491 					result = groups_search(cred->group_info, f->gid);
492 			} else if (f->op == Audit_not_equal) {
493 				if (result)
494 					result = !groups_search(cred->group_info, f->gid);
495 			}
496 			break;
497 		case AUDIT_EGID:
498 			result = audit_gid_comparator(cred->egid, f->op, f->gid);
499 			if (f->op == Audit_equal) {
500 				if (!result)
501 					result = groups_search(cred->group_info, f->gid);
502 			} else if (f->op == Audit_not_equal) {
503 				if (result)
504 					result = !groups_search(cred->group_info, f->gid);
505 			}
506 			break;
507 		case AUDIT_SGID:
508 			result = audit_gid_comparator(cred->sgid, f->op, f->gid);
509 			break;
510 		case AUDIT_FSGID:
511 			result = audit_gid_comparator(cred->fsgid, f->op, f->gid);
512 			break;
513 		case AUDIT_SESSIONID:
514 			sessionid = audit_get_sessionid(tsk);
515 			result = audit_comparator(sessionid, f->op, f->val);
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 = audit_comparator(name->ino, f->op, 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,
606 							     name->ino,
607 							     name->dev);
608 				if (f->op == Audit_not_equal)
609 					result = !result;
610 			}
611 			break;
612 		case AUDIT_DIR:
613 			if (ctx) {
614 				result = match_tree_refs(ctx, rule->tree);
615 				if (f->op == Audit_not_equal)
616 					result = !result;
617 			}
618 			break;
619 		case AUDIT_LOGINUID:
620 			result = audit_uid_comparator(audit_get_loginuid(tsk),
621 						      f->op, f->uid);
622 			break;
623 		case AUDIT_LOGINUID_SET:
624 			result = audit_comparator(audit_loginuid_set(tsk), f->op, f->val);
625 			break;
626 		case AUDIT_SADDR_FAM:
627 			if (ctx->sockaddr)
628 				result = audit_comparator(ctx->sockaddr->ss_family,
629 							  f->op, f->val);
630 			break;
631 		case AUDIT_SUBJ_USER:
632 		case AUDIT_SUBJ_ROLE:
633 		case AUDIT_SUBJ_TYPE:
634 		case AUDIT_SUBJ_SEN:
635 		case AUDIT_SUBJ_CLR:
636 			/* NOTE: this may return negative values indicating
637 			   a temporary error.  We simply treat this as a
638 			   match for now to avoid losing information that
639 			   may be wanted.   An error message will also be
640 			   logged upon error */
641 			if (f->lsm_rule) {
642 				if (need_sid) {
643 					security_task_getsecid(tsk, &sid);
644 					need_sid = 0;
645 				}
646 				result = security_audit_rule_match(sid, f->type,
647 								   f->op,
648 								   f->lsm_rule);
649 			}
650 			break;
651 		case AUDIT_OBJ_USER:
652 		case AUDIT_OBJ_ROLE:
653 		case AUDIT_OBJ_TYPE:
654 		case AUDIT_OBJ_LEV_LOW:
655 		case AUDIT_OBJ_LEV_HIGH:
656 			/* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
657 			   also applies here */
658 			if (f->lsm_rule) {
659 				/* Find files that match */
660 				if (name) {
661 					result = security_audit_rule_match(
662 								name->osid,
663 								f->type,
664 								f->op,
665 								f->lsm_rule);
666 				} else if (ctx) {
667 					list_for_each_entry(n, &ctx->names_list, list) {
668 						if (security_audit_rule_match(
669 								n->osid,
670 								f->type,
671 								f->op,
672 								f->lsm_rule)) {
673 							++result;
674 							break;
675 						}
676 					}
677 				}
678 				/* Find ipc objects that match */
679 				if (!ctx || ctx->type != AUDIT_IPC)
680 					break;
681 				if (security_audit_rule_match(ctx->ipc.osid,
682 							      f->type, f->op,
683 							      f->lsm_rule))
684 					++result;
685 			}
686 			break;
687 		case AUDIT_ARG0:
688 		case AUDIT_ARG1:
689 		case AUDIT_ARG2:
690 		case AUDIT_ARG3:
691 			if (ctx)
692 				result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
693 			break;
694 		case AUDIT_FILTERKEY:
695 			/* ignore this field for filtering */
696 			result = 1;
697 			break;
698 		case AUDIT_PERM:
699 			result = audit_match_perm(ctx, f->val);
700 			if (f->op == Audit_not_equal)
701 				result = !result;
702 			break;
703 		case AUDIT_FILETYPE:
704 			result = audit_match_filetype(ctx, f->val);
705 			if (f->op == Audit_not_equal)
706 				result = !result;
707 			break;
708 		case AUDIT_FIELD_COMPARE:
709 			result = audit_field_compare(tsk, cred, f, ctx, name);
710 			break;
711 		}
712 		if (!result)
713 			return 0;
714 	}
715 
716 	if (ctx) {
717 		if (rule->prio <= ctx->prio)
718 			return 0;
719 		if (rule->filterkey) {
720 			kfree(ctx->filterkey);
721 			ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
722 		}
723 		ctx->prio = rule->prio;
724 	}
725 	switch (rule->action) {
726 	case AUDIT_NEVER:
727 		*state = AUDIT_DISABLED;
728 		break;
729 	case AUDIT_ALWAYS:
730 		*state = AUDIT_RECORD_CONTEXT;
731 		break;
732 	}
733 	return 1;
734 }
735 
736 /* At process creation time, we can determine if system-call auditing is
737  * completely disabled for this task.  Since we only have the task
738  * structure at this point, we can only check uid and gid.
739  */
audit_filter_task(struct task_struct * tsk,char ** key)740 static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
741 {
742 	struct audit_entry *e;
743 	enum audit_state   state;
744 
745 	rcu_read_lock();
746 	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
747 		if (audit_filter_rules(tsk, &e->rule, NULL, NULL,
748 				       &state, true)) {
749 			if (state == AUDIT_RECORD_CONTEXT)
750 				*key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
751 			rcu_read_unlock();
752 			return state;
753 		}
754 	}
755 	rcu_read_unlock();
756 	return AUDIT_BUILD_CONTEXT;
757 }
758 
audit_in_mask(const struct audit_krule * rule,unsigned long val)759 static int audit_in_mask(const struct audit_krule *rule, unsigned long val)
760 {
761 	int word, bit;
762 
763 	if (val > 0xffffffff)
764 		return false;
765 
766 	word = AUDIT_WORD(val);
767 	if (word >= AUDIT_BITMASK_SIZE)
768 		return false;
769 
770 	bit = AUDIT_BIT(val);
771 
772 	return rule->mask[word] & bit;
773 }
774 
775 /* At syscall entry and exit time, this filter is called if the
776  * audit_state is not low enough that auditing cannot take place, but is
777  * also not high enough that we already know we have to write an audit
778  * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
779  */
audit_filter_syscall(struct task_struct * tsk,struct audit_context * ctx,struct list_head * list)780 static enum audit_state audit_filter_syscall(struct task_struct *tsk,
781 					     struct audit_context *ctx,
782 					     struct list_head *list)
783 {
784 	struct audit_entry *e;
785 	enum audit_state state;
786 
787 	if (auditd_test_task(tsk))
788 		return AUDIT_DISABLED;
789 
790 	rcu_read_lock();
791 	list_for_each_entry_rcu(e, list, list) {
792 		if (audit_in_mask(&e->rule, ctx->major) &&
793 		    audit_filter_rules(tsk, &e->rule, ctx, NULL,
794 				       &state, false)) {
795 			rcu_read_unlock();
796 			ctx->current_state = state;
797 			return state;
798 		}
799 	}
800 	rcu_read_unlock();
801 	return AUDIT_BUILD_CONTEXT;
802 }
803 
804 /*
805  * Given an audit_name check the inode hash table to see if they match.
806  * Called holding the rcu read lock to protect the use of audit_inode_hash
807  */
audit_filter_inode_name(struct task_struct * tsk,struct audit_names * n,struct audit_context * ctx)808 static int audit_filter_inode_name(struct task_struct *tsk,
809 				   struct audit_names *n,
810 				   struct audit_context *ctx) {
811 	int h = audit_hash_ino((u32)n->ino);
812 	struct list_head *list = &audit_inode_hash[h];
813 	struct audit_entry *e;
814 	enum audit_state state;
815 
816 	list_for_each_entry_rcu(e, list, list) {
817 		if (audit_in_mask(&e->rule, ctx->major) &&
818 		    audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) {
819 			ctx->current_state = state;
820 			return 1;
821 		}
822 	}
823 	return 0;
824 }
825 
826 /* At syscall exit time, this filter is called if any audit_names have been
827  * collected during syscall processing.  We only check rules in sublists at hash
828  * buckets applicable to the inode numbers in audit_names.
829  * Regarding audit_state, same rules apply as for audit_filter_syscall().
830  */
audit_filter_inodes(struct task_struct * tsk,struct audit_context * ctx)831 void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
832 {
833 	struct audit_names *n;
834 
835 	if (auditd_test_task(tsk))
836 		return;
837 
838 	rcu_read_lock();
839 
840 	list_for_each_entry(n, &ctx->names_list, list) {
841 		if (audit_filter_inode_name(tsk, n, ctx))
842 			break;
843 	}
844 	rcu_read_unlock();
845 }
846 
audit_proctitle_free(struct audit_context * context)847 static inline void audit_proctitle_free(struct audit_context *context)
848 {
849 	kfree(context->proctitle.value);
850 	context->proctitle.value = NULL;
851 	context->proctitle.len = 0;
852 }
853 
audit_free_module(struct audit_context * context)854 static inline void audit_free_module(struct audit_context *context)
855 {
856 	if (context->type == AUDIT_KERN_MODULE) {
857 		kfree(context->module.name);
858 		context->module.name = NULL;
859 	}
860 }
audit_free_names(struct audit_context * context)861 static inline void audit_free_names(struct audit_context *context)
862 {
863 	struct audit_names *n, *next;
864 
865 	list_for_each_entry_safe(n, next, &context->names_list, list) {
866 		list_del(&n->list);
867 		if (n->name)
868 			putname(n->name);
869 		if (n->should_free)
870 			kfree(n);
871 	}
872 	context->name_count = 0;
873 	path_put(&context->pwd);
874 	context->pwd.dentry = NULL;
875 	context->pwd.mnt = NULL;
876 }
877 
audit_free_aux(struct audit_context * context)878 static inline void audit_free_aux(struct audit_context *context)
879 {
880 	struct audit_aux_data *aux;
881 
882 	while ((aux = context->aux)) {
883 		context->aux = aux->next;
884 		kfree(aux);
885 	}
886 	while ((aux = context->aux_pids)) {
887 		context->aux_pids = aux->next;
888 		kfree(aux);
889 	}
890 }
891 
audit_alloc_context(enum audit_state state)892 static inline struct audit_context *audit_alloc_context(enum audit_state state)
893 {
894 	struct audit_context *context;
895 
896 	context = kzalloc(sizeof(*context), GFP_KERNEL);
897 	if (!context)
898 		return NULL;
899 	context->state = state;
900 	context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
901 	INIT_LIST_HEAD(&context->killed_trees);
902 	INIT_LIST_HEAD(&context->names_list);
903 	return context;
904 }
905 
906 /**
907  * audit_alloc - allocate an audit context block for a task
908  * @tsk: task
909  *
910  * Filter on the task information and allocate a per-task audit context
911  * if necessary.  Doing so turns on system call auditing for the
912  * specified task.  This is called from copy_process, so no lock is
913  * needed.
914  */
audit_alloc(struct task_struct * tsk)915 int audit_alloc(struct task_struct *tsk)
916 {
917 	struct audit_context *context;
918 	enum audit_state     state;
919 	char *key = NULL;
920 
921 	if (likely(!audit_ever_enabled))
922 		return 0; /* Return if not auditing. */
923 
924 	state = audit_filter_task(tsk, &key);
925 	if (state == AUDIT_DISABLED) {
926 		clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
927 		return 0;
928 	}
929 
930 	if (!(context = audit_alloc_context(state))) {
931 		kfree(key);
932 		audit_log_lost("out of memory in audit_alloc");
933 		return -ENOMEM;
934 	}
935 	context->filterkey = key;
936 
937 	audit_set_context(tsk, context);
938 	set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
939 	return 0;
940 }
941 
audit_free_context(struct audit_context * context)942 static inline void audit_free_context(struct audit_context *context)
943 {
944 	audit_free_module(context);
945 	audit_free_names(context);
946 	unroll_tree_refs(context, NULL, 0);
947 	free_tree_refs(context);
948 	audit_free_aux(context);
949 	kfree(context->filterkey);
950 	kfree(context->sockaddr);
951 	audit_proctitle_free(context);
952 	kfree(context);
953 }
954 
audit_log_pid_context(struct audit_context * context,pid_t pid,kuid_t auid,kuid_t uid,unsigned int sessionid,u32 sid,char * comm)955 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
956 				 kuid_t auid, kuid_t uid, unsigned int sessionid,
957 				 u32 sid, char *comm)
958 {
959 	struct audit_buffer *ab;
960 	char *ctx = NULL;
961 	u32 len;
962 	int rc = 0;
963 
964 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
965 	if (!ab)
966 		return rc;
967 
968 	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
969 			 from_kuid(&init_user_ns, auid),
970 			 from_kuid(&init_user_ns, uid), sessionid);
971 	if (sid) {
972 		if (security_secid_to_secctx(sid, &ctx, &len)) {
973 			audit_log_format(ab, " obj=(none)");
974 			rc = 1;
975 		} else {
976 			audit_log_format(ab, " obj=%s", ctx);
977 			security_release_secctx(ctx, len);
978 		}
979 	}
980 	audit_log_format(ab, " ocomm=");
981 	audit_log_untrustedstring(ab, comm);
982 	audit_log_end(ab);
983 
984 	return rc;
985 }
986 
audit_log_execve_info(struct audit_context * context,struct audit_buffer ** ab)987 static void audit_log_execve_info(struct audit_context *context,
988 				  struct audit_buffer **ab)
989 {
990 	long len_max;
991 	long len_rem;
992 	long len_full;
993 	long len_buf;
994 	long len_abuf = 0;
995 	long len_tmp;
996 	bool require_data;
997 	bool encode;
998 	unsigned int iter;
999 	unsigned int arg;
1000 	char *buf_head;
1001 	char *buf;
1002 	const char __user *p = (const char __user *)current->mm->arg_start;
1003 
1004 	/* NOTE: this buffer needs to be large enough to hold all the non-arg
1005 	 *       data we put in the audit record for this argument (see the
1006 	 *       code below) ... at this point in time 96 is plenty */
1007 	char abuf[96];
1008 
1009 	/* NOTE: we set MAX_EXECVE_AUDIT_LEN to a rather arbitrary limit, the
1010 	 *       current value of 7500 is not as important as the fact that it
1011 	 *       is less than 8k, a setting of 7500 gives us plenty of wiggle
1012 	 *       room if we go over a little bit in the logging below */
1013 	WARN_ON_ONCE(MAX_EXECVE_AUDIT_LEN > 7500);
1014 	len_max = MAX_EXECVE_AUDIT_LEN;
1015 
1016 	/* scratch buffer to hold the userspace args */
1017 	buf_head = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1018 	if (!buf_head) {
1019 		audit_panic("out of memory for argv string");
1020 		return;
1021 	}
1022 	buf = buf_head;
1023 
1024 	audit_log_format(*ab, "argc=%d", context->execve.argc);
1025 
1026 	len_rem = len_max;
1027 	len_buf = 0;
1028 	len_full = 0;
1029 	require_data = true;
1030 	encode = false;
1031 	iter = 0;
1032 	arg = 0;
1033 	do {
1034 		/* NOTE: we don't ever want to trust this value for anything
1035 		 *       serious, but the audit record format insists we
1036 		 *       provide an argument length for really long arguments,
1037 		 *       e.g. > MAX_EXECVE_AUDIT_LEN, so we have no choice but
1038 		 *       to use strncpy_from_user() to obtain this value for
1039 		 *       recording in the log, although we don't use it
1040 		 *       anywhere here to avoid a double-fetch problem */
1041 		if (len_full == 0)
1042 			len_full = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1043 
1044 		/* read more data from userspace */
1045 		if (require_data) {
1046 			/* can we make more room in the buffer? */
1047 			if (buf != buf_head) {
1048 				memmove(buf_head, buf, len_buf);
1049 				buf = buf_head;
1050 			}
1051 
1052 			/* fetch as much as we can of the argument */
1053 			len_tmp = strncpy_from_user(&buf_head[len_buf], p,
1054 						    len_max - len_buf);
1055 			if (len_tmp == -EFAULT) {
1056 				/* unable to copy from userspace */
1057 				send_sig(SIGKILL, current, 0);
1058 				goto out;
1059 			} else if (len_tmp == (len_max - len_buf)) {
1060 				/* buffer is not large enough */
1061 				require_data = true;
1062 				/* NOTE: if we are going to span multiple
1063 				 *       buffers force the encoding so we stand
1064 				 *       a chance at a sane len_full value and
1065 				 *       consistent record encoding */
1066 				encode = true;
1067 				len_full = len_full * 2;
1068 				p += len_tmp;
1069 			} else {
1070 				require_data = false;
1071 				if (!encode)
1072 					encode = audit_string_contains_control(
1073 								buf, len_tmp);
1074 				/* try to use a trusted value for len_full */
1075 				if (len_full < len_max)
1076 					len_full = (encode ?
1077 						    len_tmp * 2 : len_tmp);
1078 				p += len_tmp + 1;
1079 			}
1080 			len_buf += len_tmp;
1081 			buf_head[len_buf] = '\0';
1082 
1083 			/* length of the buffer in the audit record? */
1084 			len_abuf = (encode ? len_buf * 2 : len_buf + 2);
1085 		}
1086 
1087 		/* write as much as we can to the audit log */
1088 		if (len_buf >= 0) {
1089 			/* NOTE: some magic numbers here - basically if we
1090 			 *       can't fit a reasonable amount of data into the
1091 			 *       existing audit buffer, flush it and start with
1092 			 *       a new buffer */
1093 			if ((sizeof(abuf) + 8) > len_rem) {
1094 				len_rem = len_max;
1095 				audit_log_end(*ab);
1096 				*ab = audit_log_start(context,
1097 						      GFP_KERNEL, AUDIT_EXECVE);
1098 				if (!*ab)
1099 					goto out;
1100 			}
1101 
1102 			/* create the non-arg portion of the arg record */
1103 			len_tmp = 0;
1104 			if (require_data || (iter > 0) ||
1105 			    ((len_abuf + sizeof(abuf)) > len_rem)) {
1106 				if (iter == 0) {
1107 					len_tmp += snprintf(&abuf[len_tmp],
1108 							sizeof(abuf) - len_tmp,
1109 							" a%d_len=%lu",
1110 							arg, len_full);
1111 				}
1112 				len_tmp += snprintf(&abuf[len_tmp],
1113 						    sizeof(abuf) - len_tmp,
1114 						    " a%d[%d]=", arg, iter++);
1115 			} else
1116 				len_tmp += snprintf(&abuf[len_tmp],
1117 						    sizeof(abuf) - len_tmp,
1118 						    " a%d=", arg);
1119 			WARN_ON(len_tmp >= sizeof(abuf));
1120 			abuf[sizeof(abuf) - 1] = '\0';
1121 
1122 			/* log the arg in the audit record */
1123 			audit_log_format(*ab, "%s", abuf);
1124 			len_rem -= len_tmp;
1125 			len_tmp = len_buf;
1126 			if (encode) {
1127 				if (len_abuf > len_rem)
1128 					len_tmp = len_rem / 2; /* encoding */
1129 				audit_log_n_hex(*ab, buf, len_tmp);
1130 				len_rem -= len_tmp * 2;
1131 				len_abuf -= len_tmp * 2;
1132 			} else {
1133 				if (len_abuf > len_rem)
1134 					len_tmp = len_rem - 2; /* quotes */
1135 				audit_log_n_string(*ab, buf, len_tmp);
1136 				len_rem -= len_tmp + 2;
1137 				/* don't subtract the "2" because we still need
1138 				 * to add quotes to the remaining string */
1139 				len_abuf -= len_tmp;
1140 			}
1141 			len_buf -= len_tmp;
1142 			buf += len_tmp;
1143 		}
1144 
1145 		/* ready to move to the next argument? */
1146 		if ((len_buf == 0) && !require_data) {
1147 			arg++;
1148 			iter = 0;
1149 			len_full = 0;
1150 			require_data = true;
1151 			encode = false;
1152 		}
1153 	} while (arg < context->execve.argc);
1154 
1155 	/* NOTE: the caller handles the final audit_log_end() call */
1156 
1157 out:
1158 	kfree(buf_head);
1159 }
1160 
audit_log_cap(struct audit_buffer * ab,char * prefix,kernel_cap_t * cap)1161 static void audit_log_cap(struct audit_buffer *ab, char *prefix,
1162 			  kernel_cap_t *cap)
1163 {
1164 	int i;
1165 
1166 	if (cap_isclear(*cap)) {
1167 		audit_log_format(ab, " %s=0", prefix);
1168 		return;
1169 	}
1170 	audit_log_format(ab, " %s=", prefix);
1171 	CAP_FOR_EACH_U32(i)
1172 		audit_log_format(ab, "%08x", cap->cap[CAP_LAST_U32 - i]);
1173 }
1174 
audit_log_fcaps(struct audit_buffer * ab,struct audit_names * name)1175 static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
1176 {
1177 	if (name->fcap_ver == -1) {
1178 		audit_log_format(ab, " cap_fe=? cap_fver=? cap_fp=? cap_fi=?");
1179 		return;
1180 	}
1181 	audit_log_cap(ab, "cap_fp", &name->fcap.permitted);
1182 	audit_log_cap(ab, "cap_fi", &name->fcap.inheritable);
1183 	audit_log_format(ab, " cap_fe=%d cap_fver=%x cap_frootid=%d",
1184 			 name->fcap.fE, name->fcap_ver,
1185 			 from_kuid(&init_user_ns, name->fcap.rootid));
1186 }
1187 
show_special(struct audit_context * context,int * call_panic)1188 static void show_special(struct audit_context *context, int *call_panic)
1189 {
1190 	struct audit_buffer *ab;
1191 	int i;
1192 
1193 	ab = audit_log_start(context, GFP_KERNEL, context->type);
1194 	if (!ab)
1195 		return;
1196 
1197 	switch (context->type) {
1198 	case AUDIT_SOCKETCALL: {
1199 		int nargs = context->socketcall.nargs;
1200 		audit_log_format(ab, "nargs=%d", nargs);
1201 		for (i = 0; i < nargs; i++)
1202 			audit_log_format(ab, " a%d=%lx", i,
1203 				context->socketcall.args[i]);
1204 		break; }
1205 	case AUDIT_IPC: {
1206 		u32 osid = context->ipc.osid;
1207 
1208 		audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
1209 				 from_kuid(&init_user_ns, context->ipc.uid),
1210 				 from_kgid(&init_user_ns, context->ipc.gid),
1211 				 context->ipc.mode);
1212 		if (osid) {
1213 			char *ctx = NULL;
1214 			u32 len;
1215 			if (security_secid_to_secctx(osid, &ctx, &len)) {
1216 				audit_log_format(ab, " osid=%u", osid);
1217 				*call_panic = 1;
1218 			} else {
1219 				audit_log_format(ab, " obj=%s", ctx);
1220 				security_release_secctx(ctx, len);
1221 			}
1222 		}
1223 		if (context->ipc.has_perm) {
1224 			audit_log_end(ab);
1225 			ab = audit_log_start(context, GFP_KERNEL,
1226 					     AUDIT_IPC_SET_PERM);
1227 			if (unlikely(!ab))
1228 				return;
1229 			audit_log_format(ab,
1230 				"qbytes=%lx ouid=%u ogid=%u mode=%#ho",
1231 				context->ipc.qbytes,
1232 				context->ipc.perm_uid,
1233 				context->ipc.perm_gid,
1234 				context->ipc.perm_mode);
1235 		}
1236 		break; }
1237 	case AUDIT_MQ_OPEN:
1238 		audit_log_format(ab,
1239 			"oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "
1240 			"mq_msgsize=%ld mq_curmsgs=%ld",
1241 			context->mq_open.oflag, context->mq_open.mode,
1242 			context->mq_open.attr.mq_flags,
1243 			context->mq_open.attr.mq_maxmsg,
1244 			context->mq_open.attr.mq_msgsize,
1245 			context->mq_open.attr.mq_curmsgs);
1246 		break;
1247 	case AUDIT_MQ_SENDRECV:
1248 		audit_log_format(ab,
1249 			"mqdes=%d msg_len=%zd msg_prio=%u "
1250 			"abs_timeout_sec=%lld abs_timeout_nsec=%ld",
1251 			context->mq_sendrecv.mqdes,
1252 			context->mq_sendrecv.msg_len,
1253 			context->mq_sendrecv.msg_prio,
1254 			(long long) context->mq_sendrecv.abs_timeout.tv_sec,
1255 			context->mq_sendrecv.abs_timeout.tv_nsec);
1256 		break;
1257 	case AUDIT_MQ_NOTIFY:
1258 		audit_log_format(ab, "mqdes=%d sigev_signo=%d",
1259 				context->mq_notify.mqdes,
1260 				context->mq_notify.sigev_signo);
1261 		break;
1262 	case AUDIT_MQ_GETSETATTR: {
1263 		struct mq_attr *attr = &context->mq_getsetattr.mqstat;
1264 		audit_log_format(ab,
1265 			"mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1266 			"mq_curmsgs=%ld ",
1267 			context->mq_getsetattr.mqdes,
1268 			attr->mq_flags, attr->mq_maxmsg,
1269 			attr->mq_msgsize, attr->mq_curmsgs);
1270 		break; }
1271 	case AUDIT_CAPSET:
1272 		audit_log_format(ab, "pid=%d", context->capset.pid);
1273 		audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
1274 		audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
1275 		audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
1276 		audit_log_cap(ab, "cap_pa", &context->capset.cap.ambient);
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 	case AUDIT_EXECVE:
1283 		audit_log_execve_info(context, &ab);
1284 		break;
1285 	case AUDIT_KERN_MODULE:
1286 		audit_log_format(ab, "name=");
1287 		if (context->module.name) {
1288 			audit_log_untrustedstring(ab, context->module.name);
1289 		} else
1290 			audit_log_format(ab, "(null)");
1291 
1292 		break;
1293 	}
1294 	audit_log_end(ab);
1295 }
1296 
audit_proctitle_rtrim(char * proctitle,int len)1297 static inline int audit_proctitle_rtrim(char *proctitle, int len)
1298 {
1299 	char *end = proctitle + len - 1;
1300 	while (end > proctitle && !isprint(*end))
1301 		end--;
1302 
1303 	/* catch the case where proctitle is only 1 non-print character */
1304 	len = end - proctitle + 1;
1305 	len -= isprint(proctitle[len-1]) == 0;
1306 	return len;
1307 }
1308 
1309 /*
1310  * audit_log_name - produce AUDIT_PATH record from struct audit_names
1311  * @context: audit_context for the task
1312  * @n: audit_names structure with reportable details
1313  * @path: optional path to report instead of audit_names->name
1314  * @record_num: record number to report when handling a list of names
1315  * @call_panic: optional pointer to int that will be updated if secid fails
1316  */
audit_log_name(struct audit_context * context,struct audit_names * n,const struct path * path,int record_num,int * call_panic)1317 static void audit_log_name(struct audit_context *context, struct audit_names *n,
1318 		    const struct path *path, int record_num, int *call_panic)
1319 {
1320 	struct audit_buffer *ab;
1321 
1322 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1323 	if (!ab)
1324 		return;
1325 
1326 	audit_log_format(ab, "item=%d", record_num);
1327 
1328 	if (path)
1329 		audit_log_d_path(ab, " name=", path);
1330 	else if (n->name) {
1331 		switch (n->name_len) {
1332 		case AUDIT_NAME_FULL:
1333 			/* log the full path */
1334 			audit_log_format(ab, " name=");
1335 			audit_log_untrustedstring(ab, n->name->name);
1336 			break;
1337 		case 0:
1338 			/* name was specified as a relative path and the
1339 			 * directory component is the cwd
1340 			 */
1341 			audit_log_d_path(ab, " name=", &context->pwd);
1342 			break;
1343 		default:
1344 			/* log the name's directory component */
1345 			audit_log_format(ab, " name=");
1346 			audit_log_n_untrustedstring(ab, n->name->name,
1347 						    n->name_len);
1348 		}
1349 	} else
1350 		audit_log_format(ab, " name=(null)");
1351 
1352 	if (n->ino != AUDIT_INO_UNSET)
1353 		audit_log_format(ab, " inode=%lu dev=%02x:%02x mode=%#ho ouid=%u ogid=%u rdev=%02x:%02x",
1354 				 n->ino,
1355 				 MAJOR(n->dev),
1356 				 MINOR(n->dev),
1357 				 n->mode,
1358 				 from_kuid(&init_user_ns, n->uid),
1359 				 from_kgid(&init_user_ns, n->gid),
1360 				 MAJOR(n->rdev),
1361 				 MINOR(n->rdev));
1362 	if (n->osid != 0) {
1363 		char *ctx = NULL;
1364 		u32 len;
1365 
1366 		if (security_secid_to_secctx(
1367 			n->osid, &ctx, &len)) {
1368 			audit_log_format(ab, " osid=%u", n->osid);
1369 			if (call_panic)
1370 				*call_panic = 2;
1371 		} else {
1372 			audit_log_format(ab, " obj=%s", ctx);
1373 			security_release_secctx(ctx, len);
1374 		}
1375 	}
1376 
1377 	/* log the audit_names record type */
1378 	switch (n->type) {
1379 	case AUDIT_TYPE_NORMAL:
1380 		audit_log_format(ab, " nametype=NORMAL");
1381 		break;
1382 	case AUDIT_TYPE_PARENT:
1383 		audit_log_format(ab, " nametype=PARENT");
1384 		break;
1385 	case AUDIT_TYPE_CHILD_DELETE:
1386 		audit_log_format(ab, " nametype=DELETE");
1387 		break;
1388 	case AUDIT_TYPE_CHILD_CREATE:
1389 		audit_log_format(ab, " nametype=CREATE");
1390 		break;
1391 	default:
1392 		audit_log_format(ab, " nametype=UNKNOWN");
1393 		break;
1394 	}
1395 
1396 	audit_log_fcaps(ab, n);
1397 	audit_log_end(ab);
1398 }
1399 
audit_log_proctitle(void)1400 static void audit_log_proctitle(void)
1401 {
1402 	int res;
1403 	char *buf;
1404 	char *msg = "(null)";
1405 	int len = strlen(msg);
1406 	struct audit_context *context = audit_context();
1407 	struct audit_buffer *ab;
1408 
1409 	if (!context || context->dummy)
1410 		return;
1411 
1412 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE);
1413 	if (!ab)
1414 		return;	/* audit_panic or being filtered */
1415 
1416 	audit_log_format(ab, "proctitle=");
1417 
1418 	/* Not  cached */
1419 	if (!context->proctitle.value) {
1420 		buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL);
1421 		if (!buf)
1422 			goto out;
1423 		/* Historically called this from procfs naming */
1424 		res = get_cmdline(current, buf, MAX_PROCTITLE_AUDIT_LEN);
1425 		if (res == 0) {
1426 			kfree(buf);
1427 			goto out;
1428 		}
1429 		res = audit_proctitle_rtrim(buf, res);
1430 		if (res == 0) {
1431 			kfree(buf);
1432 			goto out;
1433 		}
1434 		context->proctitle.value = buf;
1435 		context->proctitle.len = res;
1436 	}
1437 	msg = context->proctitle.value;
1438 	len = context->proctitle.len;
1439 out:
1440 	audit_log_n_untrustedstring(ab, msg, len);
1441 	audit_log_end(ab);
1442 }
1443 
audit_log_exit(void)1444 static void audit_log_exit(void)
1445 {
1446 	int i, call_panic = 0;
1447 	struct audit_context *context = audit_context();
1448 	struct audit_buffer *ab;
1449 	struct audit_aux_data *aux;
1450 	struct audit_names *n;
1451 
1452 	context->personality = current->personality;
1453 
1454 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1455 	if (!ab)
1456 		return;		/* audit_panic has been called */
1457 	audit_log_format(ab, "arch=%x syscall=%d",
1458 			 context->arch, context->major);
1459 	if (context->personality != PER_LINUX)
1460 		audit_log_format(ab, " per=%lx", context->personality);
1461 	if (context->return_valid)
1462 		audit_log_format(ab, " success=%s exit=%ld",
1463 				 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
1464 				 context->return_code);
1465 
1466 	audit_log_format(ab,
1467 			 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d",
1468 			 context->argv[0],
1469 			 context->argv[1],
1470 			 context->argv[2],
1471 			 context->argv[3],
1472 			 context->name_count);
1473 
1474 	audit_log_task_info(ab);
1475 	audit_log_key(ab, context->filterkey);
1476 	audit_log_end(ab);
1477 
1478 	for (aux = context->aux; aux; aux = aux->next) {
1479 
1480 		ab = audit_log_start(context, GFP_KERNEL, aux->type);
1481 		if (!ab)
1482 			continue; /* audit_panic has been called */
1483 
1484 		switch (aux->type) {
1485 
1486 		case AUDIT_BPRM_FCAPS: {
1487 			struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
1488 			audit_log_format(ab, "fver=%x", axs->fcap_ver);
1489 			audit_log_cap(ab, "fp", &axs->fcap.permitted);
1490 			audit_log_cap(ab, "fi", &axs->fcap.inheritable);
1491 			audit_log_format(ab, " fe=%d", axs->fcap.fE);
1492 			audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
1493 			audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
1494 			audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
1495 			audit_log_cap(ab, "old_pa", &axs->old_pcap.ambient);
1496 			audit_log_cap(ab, "pp", &axs->new_pcap.permitted);
1497 			audit_log_cap(ab, "pi", &axs->new_pcap.inheritable);
1498 			audit_log_cap(ab, "pe", &axs->new_pcap.effective);
1499 			audit_log_cap(ab, "pa", &axs->new_pcap.ambient);
1500 			audit_log_format(ab, " frootid=%d",
1501 					 from_kuid(&init_user_ns,
1502 						   axs->fcap.rootid));
1503 			break; }
1504 
1505 		}
1506 		audit_log_end(ab);
1507 	}
1508 
1509 	if (context->type)
1510 		show_special(context, &call_panic);
1511 
1512 	if (context->fds[0] >= 0) {
1513 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
1514 		if (ab) {
1515 			audit_log_format(ab, "fd0=%d fd1=%d",
1516 					context->fds[0], context->fds[1]);
1517 			audit_log_end(ab);
1518 		}
1519 	}
1520 
1521 	if (context->sockaddr_len) {
1522 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
1523 		if (ab) {
1524 			audit_log_format(ab, "saddr=");
1525 			audit_log_n_hex(ab, (void *)context->sockaddr,
1526 					context->sockaddr_len);
1527 			audit_log_end(ab);
1528 		}
1529 	}
1530 
1531 	for (aux = context->aux_pids; aux; aux = aux->next) {
1532 		struct audit_aux_data_pids *axs = (void *)aux;
1533 
1534 		for (i = 0; i < axs->pid_count; i++)
1535 			if (audit_log_pid_context(context, axs->target_pid[i],
1536 						  axs->target_auid[i],
1537 						  axs->target_uid[i],
1538 						  axs->target_sessionid[i],
1539 						  axs->target_sid[i],
1540 						  axs->target_comm[i]))
1541 				call_panic = 1;
1542 	}
1543 
1544 	if (context->target_pid &&
1545 	    audit_log_pid_context(context, context->target_pid,
1546 				  context->target_auid, context->target_uid,
1547 				  context->target_sessionid,
1548 				  context->target_sid, context->target_comm))
1549 			call_panic = 1;
1550 
1551 	if (context->pwd.dentry && context->pwd.mnt) {
1552 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1553 		if (ab) {
1554 			audit_log_d_path(ab, "cwd=", &context->pwd);
1555 			audit_log_end(ab);
1556 		}
1557 	}
1558 
1559 	i = 0;
1560 	list_for_each_entry(n, &context->names_list, list) {
1561 		if (n->hidden)
1562 			continue;
1563 		audit_log_name(context, n, NULL, i++, &call_panic);
1564 	}
1565 
1566 	audit_log_proctitle();
1567 
1568 	/* Send end of event record to help user space know we are finished */
1569 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1570 	if (ab)
1571 		audit_log_end(ab);
1572 	if (call_panic)
1573 		audit_panic("error converting sid to string");
1574 }
1575 
1576 /**
1577  * __audit_free - free a per-task audit context
1578  * @tsk: task whose audit context block to free
1579  *
1580  * Called from copy_process and do_exit
1581  */
__audit_free(struct task_struct * tsk)1582 void __audit_free(struct task_struct *tsk)
1583 {
1584 	struct audit_context *context = tsk->audit_context;
1585 
1586 	if (!context)
1587 		return;
1588 
1589 	if (!list_empty(&context->killed_trees))
1590 		audit_kill_trees(context);
1591 
1592 	/* We are called either by do_exit() or the fork() error handling code;
1593 	 * in the former case tsk == current and in the latter tsk is a
1594 	 * random task_struct that doesn't doesn't have any meaningful data we
1595 	 * need to log via audit_log_exit().
1596 	 */
1597 	if (tsk == current && !context->dummy && context->in_syscall) {
1598 		context->return_valid = 0;
1599 		context->return_code = 0;
1600 
1601 		audit_filter_syscall(tsk, context,
1602 				     &audit_filter_list[AUDIT_FILTER_EXIT]);
1603 		audit_filter_inodes(tsk, context);
1604 		if (context->current_state == AUDIT_RECORD_CONTEXT)
1605 			audit_log_exit();
1606 	}
1607 
1608 	audit_set_context(tsk, NULL);
1609 	audit_free_context(context);
1610 }
1611 
1612 /**
1613  * __audit_syscall_entry - fill in an audit record at syscall entry
1614  * @major: major syscall type (function)
1615  * @a1: additional syscall register 1
1616  * @a2: additional syscall register 2
1617  * @a3: additional syscall register 3
1618  * @a4: additional syscall register 4
1619  *
1620  * Fill in audit context at syscall entry.  This only happens if the
1621  * audit context was created when the task was created and the state or
1622  * filters demand the audit context be built.  If the state from the
1623  * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1624  * then the record will be written at syscall exit time (otherwise, it
1625  * will only be written if another part of the kernel requests that it
1626  * be written).
1627  */
__audit_syscall_entry(int major,unsigned long a1,unsigned long a2,unsigned long a3,unsigned long a4)1628 void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2,
1629 			   unsigned long a3, unsigned long a4)
1630 {
1631 	struct audit_context *context = audit_context();
1632 	enum audit_state     state;
1633 
1634 	if (!audit_enabled || !context)
1635 		return;
1636 
1637 	BUG_ON(context->in_syscall || context->name_count);
1638 
1639 	state = context->state;
1640 	if (state == AUDIT_DISABLED)
1641 		return;
1642 
1643 	context->dummy = !audit_n_rules;
1644 	if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
1645 		context->prio = 0;
1646 		if (auditd_test_task(current))
1647 			return;
1648 	}
1649 
1650 	context->arch	    = syscall_get_arch(current);
1651 	context->major      = major;
1652 	context->argv[0]    = a1;
1653 	context->argv[1]    = a2;
1654 	context->argv[2]    = a3;
1655 	context->argv[3]    = a4;
1656 	context->serial     = 0;
1657 	context->in_syscall = 1;
1658 	context->current_state  = state;
1659 	context->ppid       = 0;
1660 	ktime_get_coarse_real_ts64(&context->ctime);
1661 }
1662 
1663 /**
1664  * __audit_syscall_exit - deallocate audit context after a system call
1665  * @success: success value of the syscall
1666  * @return_code: return value of the syscall
1667  *
1668  * Tear down after system call.  If the audit context has been marked as
1669  * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1670  * filtering, or because some other part of the kernel wrote an audit
1671  * message), then write out the syscall information.  In call cases,
1672  * free the names stored from getname().
1673  */
__audit_syscall_exit(int success,long return_code)1674 void __audit_syscall_exit(int success, long return_code)
1675 {
1676 	struct audit_context *context;
1677 
1678 	context = audit_context();
1679 	if (!context)
1680 		return;
1681 
1682 	if (!list_empty(&context->killed_trees))
1683 		audit_kill_trees(context);
1684 
1685 	if (!context->dummy && context->in_syscall) {
1686 		if (success)
1687 			context->return_valid = AUDITSC_SUCCESS;
1688 		else
1689 			context->return_valid = AUDITSC_FAILURE;
1690 
1691 		/*
1692 		 * we need to fix up the return code in the audit logs if the
1693 		 * actual return codes are later going to be fixed up by the
1694 		 * arch specific signal handlers
1695 		 *
1696 		 * This is actually a test for:
1697 		 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
1698 		 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
1699 		 *
1700 		 * but is faster than a bunch of ||
1701 		 */
1702 		if (unlikely(return_code <= -ERESTARTSYS) &&
1703 		    (return_code >= -ERESTART_RESTARTBLOCK) &&
1704 		    (return_code != -ENOIOCTLCMD))
1705 			context->return_code = -EINTR;
1706 		else
1707 			context->return_code  = return_code;
1708 
1709 		audit_filter_syscall(current, context,
1710 				     &audit_filter_list[AUDIT_FILTER_EXIT]);
1711 		audit_filter_inodes(current, context);
1712 		if (context->current_state == AUDIT_RECORD_CONTEXT)
1713 			audit_log_exit();
1714 	}
1715 
1716 	context->in_syscall = 0;
1717 	context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
1718 
1719 	audit_free_module(context);
1720 	audit_free_names(context);
1721 	unroll_tree_refs(context, NULL, 0);
1722 	audit_free_aux(context);
1723 	context->aux = NULL;
1724 	context->aux_pids = NULL;
1725 	context->target_pid = 0;
1726 	context->target_sid = 0;
1727 	context->sockaddr_len = 0;
1728 	context->type = 0;
1729 	context->fds[0] = -1;
1730 	if (context->state != AUDIT_RECORD_CONTEXT) {
1731 		kfree(context->filterkey);
1732 		context->filterkey = NULL;
1733 	}
1734 }
1735 
handle_one(const struct inode * inode)1736 static inline void handle_one(const struct inode *inode)
1737 {
1738 	struct audit_context *context;
1739 	struct audit_tree_refs *p;
1740 	struct audit_chunk *chunk;
1741 	int count;
1742 	if (likely(!inode->i_fsnotify_marks))
1743 		return;
1744 	context = audit_context();
1745 	p = context->trees;
1746 	count = context->tree_count;
1747 	rcu_read_lock();
1748 	chunk = audit_tree_lookup(inode);
1749 	rcu_read_unlock();
1750 	if (!chunk)
1751 		return;
1752 	if (likely(put_tree_ref(context, chunk)))
1753 		return;
1754 	if (unlikely(!grow_tree_refs(context))) {
1755 		pr_warn("out of memory, audit has lost a tree reference\n");
1756 		audit_set_auditable(context);
1757 		audit_put_chunk(chunk);
1758 		unroll_tree_refs(context, p, count);
1759 		return;
1760 	}
1761 	put_tree_ref(context, chunk);
1762 }
1763 
handle_path(const struct dentry * dentry)1764 static void handle_path(const struct dentry *dentry)
1765 {
1766 	struct audit_context *context;
1767 	struct audit_tree_refs *p;
1768 	const struct dentry *d, *parent;
1769 	struct audit_chunk *drop;
1770 	unsigned long seq;
1771 	int count;
1772 
1773 	context = audit_context();
1774 	p = context->trees;
1775 	count = context->tree_count;
1776 retry:
1777 	drop = NULL;
1778 	d = dentry;
1779 	rcu_read_lock();
1780 	seq = read_seqbegin(&rename_lock);
1781 	for(;;) {
1782 		struct inode *inode = d_backing_inode(d);
1783 		if (inode && unlikely(inode->i_fsnotify_marks)) {
1784 			struct audit_chunk *chunk;
1785 			chunk = audit_tree_lookup(inode);
1786 			if (chunk) {
1787 				if (unlikely(!put_tree_ref(context, chunk))) {
1788 					drop = chunk;
1789 					break;
1790 				}
1791 			}
1792 		}
1793 		parent = d->d_parent;
1794 		if (parent == d)
1795 			break;
1796 		d = parent;
1797 	}
1798 	if (unlikely(read_seqretry(&rename_lock, seq) || drop)) {  /* in this order */
1799 		rcu_read_unlock();
1800 		if (!drop) {
1801 			/* just a race with rename */
1802 			unroll_tree_refs(context, p, count);
1803 			goto retry;
1804 		}
1805 		audit_put_chunk(drop);
1806 		if (grow_tree_refs(context)) {
1807 			/* OK, got more space */
1808 			unroll_tree_refs(context, p, count);
1809 			goto retry;
1810 		}
1811 		/* too bad */
1812 		pr_warn("out of memory, audit has lost a tree reference\n");
1813 		unroll_tree_refs(context, p, count);
1814 		audit_set_auditable(context);
1815 		return;
1816 	}
1817 	rcu_read_unlock();
1818 }
1819 
audit_alloc_name(struct audit_context * context,unsigned char type)1820 static struct audit_names *audit_alloc_name(struct audit_context *context,
1821 						unsigned char type)
1822 {
1823 	struct audit_names *aname;
1824 
1825 	if (context->name_count < AUDIT_NAMES) {
1826 		aname = &context->preallocated_names[context->name_count];
1827 		memset(aname, 0, sizeof(*aname));
1828 	} else {
1829 		aname = kzalloc(sizeof(*aname), GFP_NOFS);
1830 		if (!aname)
1831 			return NULL;
1832 		aname->should_free = true;
1833 	}
1834 
1835 	aname->ino = AUDIT_INO_UNSET;
1836 	aname->type = type;
1837 	list_add_tail(&aname->list, &context->names_list);
1838 
1839 	context->name_count++;
1840 	return aname;
1841 }
1842 
1843 /**
1844  * __audit_reusename - fill out filename with info from existing entry
1845  * @uptr: userland ptr to pathname
1846  *
1847  * Search the audit_names list for the current audit context. If there is an
1848  * existing entry with a matching "uptr" then return the filename
1849  * associated with that audit_name. If not, return NULL.
1850  */
1851 struct filename *
__audit_reusename(const __user char * uptr)1852 __audit_reusename(const __user char *uptr)
1853 {
1854 	struct audit_context *context = audit_context();
1855 	struct audit_names *n;
1856 
1857 	list_for_each_entry(n, &context->names_list, list) {
1858 		if (!n->name)
1859 			continue;
1860 		if (n->name->uptr == uptr) {
1861 			n->name->refcnt++;
1862 			return n->name;
1863 		}
1864 	}
1865 	return NULL;
1866 }
1867 
1868 /**
1869  * __audit_getname - add a name to the list
1870  * @name: name to add
1871  *
1872  * Add a name to the list of audit names for this context.
1873  * Called from fs/namei.c:getname().
1874  */
__audit_getname(struct filename * name)1875 void __audit_getname(struct filename *name)
1876 {
1877 	struct audit_context *context = audit_context();
1878 	struct audit_names *n;
1879 
1880 	if (!context->in_syscall)
1881 		return;
1882 
1883 	n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
1884 	if (!n)
1885 		return;
1886 
1887 	n->name = name;
1888 	n->name_len = AUDIT_NAME_FULL;
1889 	name->aname = n;
1890 	name->refcnt++;
1891 
1892 	if (!context->pwd.dentry)
1893 		get_fs_pwd(current->fs, &context->pwd);
1894 }
1895 
audit_copy_fcaps(struct audit_names * name,const struct dentry * dentry)1896 static inline int audit_copy_fcaps(struct audit_names *name,
1897 				   const struct dentry *dentry)
1898 {
1899 	struct cpu_vfs_cap_data caps;
1900 	int rc;
1901 
1902 	if (!dentry)
1903 		return 0;
1904 
1905 	rc = get_vfs_caps_from_disk(dentry, &caps);
1906 	if (rc)
1907 		return rc;
1908 
1909 	name->fcap.permitted = caps.permitted;
1910 	name->fcap.inheritable = caps.inheritable;
1911 	name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
1912 	name->fcap.rootid = caps.rootid;
1913 	name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >>
1914 				VFS_CAP_REVISION_SHIFT;
1915 
1916 	return 0;
1917 }
1918 
1919 /* Copy inode data into an audit_names. */
audit_copy_inode(struct audit_names * name,const struct dentry * dentry,struct inode * inode,unsigned int flags)1920 static void audit_copy_inode(struct audit_names *name,
1921 			     const struct dentry *dentry,
1922 			     struct inode *inode, unsigned int flags)
1923 {
1924 	name->ino   = inode->i_ino;
1925 	name->dev   = inode->i_sb->s_dev;
1926 	name->mode  = inode->i_mode;
1927 	name->uid   = inode->i_uid;
1928 	name->gid   = inode->i_gid;
1929 	name->rdev  = inode->i_rdev;
1930 	security_inode_getsecid(inode, &name->osid);
1931 	if (flags & AUDIT_INODE_NOEVAL) {
1932 		name->fcap_ver = -1;
1933 		return;
1934 	}
1935 	audit_copy_fcaps(name, dentry);
1936 }
1937 
1938 /**
1939  * __audit_inode - store the inode and device from a lookup
1940  * @name: name being audited
1941  * @dentry: dentry being audited
1942  * @flags: attributes for this particular entry
1943  */
__audit_inode(struct filename * name,const struct dentry * dentry,unsigned int flags)1944 void __audit_inode(struct filename *name, const struct dentry *dentry,
1945 		   unsigned int flags)
1946 {
1947 	struct audit_context *context = audit_context();
1948 	struct inode *inode = d_backing_inode(dentry);
1949 	struct audit_names *n;
1950 	bool parent = flags & AUDIT_INODE_PARENT;
1951 	struct audit_entry *e;
1952 	struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS];
1953 	int i;
1954 
1955 	if (!context->in_syscall)
1956 		return;
1957 
1958 	rcu_read_lock();
1959 	list_for_each_entry_rcu(e, list, list) {
1960 		for (i = 0; i < e->rule.field_count; i++) {
1961 			struct audit_field *f = &e->rule.fields[i];
1962 
1963 			if (f->type == AUDIT_FSTYPE
1964 			    && audit_comparator(inode->i_sb->s_magic,
1965 						f->op, f->val)
1966 			    && e->rule.action == AUDIT_NEVER) {
1967 				rcu_read_unlock();
1968 				return;
1969 			}
1970 		}
1971 	}
1972 	rcu_read_unlock();
1973 
1974 	if (!name)
1975 		goto out_alloc;
1976 
1977 	/*
1978 	 * If we have a pointer to an audit_names entry already, then we can
1979 	 * just use it directly if the type is correct.
1980 	 */
1981 	n = name->aname;
1982 	if (n) {
1983 		if (parent) {
1984 			if (n->type == AUDIT_TYPE_PARENT ||
1985 			    n->type == AUDIT_TYPE_UNKNOWN)
1986 				goto out;
1987 		} else {
1988 			if (n->type != AUDIT_TYPE_PARENT)
1989 				goto out;
1990 		}
1991 	}
1992 
1993 	list_for_each_entry_reverse(n, &context->names_list, list) {
1994 		if (n->ino) {
1995 			/* valid inode number, use that for the comparison */
1996 			if (n->ino != inode->i_ino ||
1997 			    n->dev != inode->i_sb->s_dev)
1998 				continue;
1999 		} else if (n->name) {
2000 			/* inode number has not been set, check the name */
2001 			if (strcmp(n->name->name, name->name))
2002 				continue;
2003 		} else
2004 			/* no inode and no name (?!) ... this is odd ... */
2005 			continue;
2006 
2007 		/* match the correct record type */
2008 		if (parent) {
2009 			if (n->type == AUDIT_TYPE_PARENT ||
2010 			    n->type == AUDIT_TYPE_UNKNOWN)
2011 				goto out;
2012 		} else {
2013 			if (n->type != AUDIT_TYPE_PARENT)
2014 				goto out;
2015 		}
2016 	}
2017 
2018 out_alloc:
2019 	/* unable to find an entry with both a matching name and type */
2020 	n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
2021 	if (!n)
2022 		return;
2023 	if (name) {
2024 		n->name = name;
2025 		name->refcnt++;
2026 	}
2027 
2028 out:
2029 	if (parent) {
2030 		n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL;
2031 		n->type = AUDIT_TYPE_PARENT;
2032 		if (flags & AUDIT_INODE_HIDDEN)
2033 			n->hidden = true;
2034 	} else {
2035 		n->name_len = AUDIT_NAME_FULL;
2036 		n->type = AUDIT_TYPE_NORMAL;
2037 	}
2038 	handle_path(dentry);
2039 	audit_copy_inode(n, dentry, inode, flags & AUDIT_INODE_NOEVAL);
2040 }
2041 
__audit_file(const struct file * file)2042 void __audit_file(const struct file *file)
2043 {
2044 	__audit_inode(NULL, file->f_path.dentry, 0);
2045 }
2046 
2047 /**
2048  * __audit_inode_child - collect inode info for created/removed objects
2049  * @parent: inode of dentry parent
2050  * @dentry: dentry being audited
2051  * @type:   AUDIT_TYPE_* value that we're looking for
2052  *
2053  * For syscalls that create or remove filesystem objects, audit_inode
2054  * can only collect information for the filesystem object's parent.
2055  * This call updates the audit context with the child's information.
2056  * Syscalls that create a new filesystem object must be hooked after
2057  * the object is created.  Syscalls that remove a filesystem object
2058  * must be hooked prior, in order to capture the target inode during
2059  * unsuccessful attempts.
2060  */
__audit_inode_child(struct inode * parent,const struct dentry * dentry,const unsigned char type)2061 void __audit_inode_child(struct inode *parent,
2062 			 const struct dentry *dentry,
2063 			 const unsigned char type)
2064 {
2065 	struct audit_context *context = audit_context();
2066 	struct inode *inode = d_backing_inode(dentry);
2067 	const struct qstr *dname = &dentry->d_name;
2068 	struct audit_names *n, *found_parent = NULL, *found_child = NULL;
2069 	struct audit_entry *e;
2070 	struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS];
2071 	int i;
2072 
2073 	if (!context->in_syscall)
2074 		return;
2075 
2076 	rcu_read_lock();
2077 	list_for_each_entry_rcu(e, list, list) {
2078 		for (i = 0; i < e->rule.field_count; i++) {
2079 			struct audit_field *f = &e->rule.fields[i];
2080 
2081 			if (f->type == AUDIT_FSTYPE
2082 			    && audit_comparator(parent->i_sb->s_magic,
2083 						f->op, f->val)
2084 			    && e->rule.action == AUDIT_NEVER) {
2085 				rcu_read_unlock();
2086 				return;
2087 			}
2088 		}
2089 	}
2090 	rcu_read_unlock();
2091 
2092 	if (inode)
2093 		handle_one(inode);
2094 
2095 	/* look for a parent entry first */
2096 	list_for_each_entry(n, &context->names_list, list) {
2097 		if (!n->name ||
2098 		    (n->type != AUDIT_TYPE_PARENT &&
2099 		     n->type != AUDIT_TYPE_UNKNOWN))
2100 			continue;
2101 
2102 		if (n->ino == parent->i_ino && n->dev == parent->i_sb->s_dev &&
2103 		    !audit_compare_dname_path(dname,
2104 					      n->name->name, n->name_len)) {
2105 			if (n->type == AUDIT_TYPE_UNKNOWN)
2106 				n->type = AUDIT_TYPE_PARENT;
2107 			found_parent = n;
2108 			break;
2109 		}
2110 	}
2111 
2112 	/* is there a matching child entry? */
2113 	list_for_each_entry(n, &context->names_list, list) {
2114 		/* can only match entries that have a name */
2115 		if (!n->name ||
2116 		    (n->type != type && n->type != AUDIT_TYPE_UNKNOWN))
2117 			continue;
2118 
2119 		if (!strcmp(dname->name, n->name->name) ||
2120 		    !audit_compare_dname_path(dname, n->name->name,
2121 						found_parent ?
2122 						found_parent->name_len :
2123 						AUDIT_NAME_FULL)) {
2124 			if (n->type == AUDIT_TYPE_UNKNOWN)
2125 				n->type = type;
2126 			found_child = n;
2127 			break;
2128 		}
2129 	}
2130 
2131 	if (!found_parent) {
2132 		/* create a new, "anonymous" parent record */
2133 		n = audit_alloc_name(context, AUDIT_TYPE_PARENT);
2134 		if (!n)
2135 			return;
2136 		audit_copy_inode(n, NULL, parent, 0);
2137 	}
2138 
2139 	if (!found_child) {
2140 		found_child = audit_alloc_name(context, type);
2141 		if (!found_child)
2142 			return;
2143 
2144 		/* Re-use the name belonging to the slot for a matching parent
2145 		 * directory. All names for this context are relinquished in
2146 		 * audit_free_names() */
2147 		if (found_parent) {
2148 			found_child->name = found_parent->name;
2149 			found_child->name_len = AUDIT_NAME_FULL;
2150 			found_child->name->refcnt++;
2151 		}
2152 	}
2153 
2154 	if (inode)
2155 		audit_copy_inode(found_child, dentry, inode, 0);
2156 	else
2157 		found_child->ino = AUDIT_INO_UNSET;
2158 }
2159 EXPORT_SYMBOL_GPL(__audit_inode_child);
2160 
2161 /**
2162  * auditsc_get_stamp - get local copies of audit_context values
2163  * @ctx: audit_context for the task
2164  * @t: timespec64 to store time recorded in the audit_context
2165  * @serial: serial value that is recorded in the audit_context
2166  *
2167  * Also sets the context as auditable.
2168  */
auditsc_get_stamp(struct audit_context * ctx,struct timespec64 * t,unsigned int * serial)2169 int auditsc_get_stamp(struct audit_context *ctx,
2170 		       struct timespec64 *t, unsigned int *serial)
2171 {
2172 	if (!ctx->in_syscall)
2173 		return 0;
2174 	if (!ctx->serial)
2175 		ctx->serial = audit_serial();
2176 	t->tv_sec  = ctx->ctime.tv_sec;
2177 	t->tv_nsec = ctx->ctime.tv_nsec;
2178 	*serial    = ctx->serial;
2179 	if (!ctx->prio) {
2180 		ctx->prio = 1;
2181 		ctx->current_state = AUDIT_RECORD_CONTEXT;
2182 	}
2183 	return 1;
2184 }
2185 
2186 /**
2187  * __audit_mq_open - record audit data for a POSIX MQ open
2188  * @oflag: open flag
2189  * @mode: mode bits
2190  * @attr: queue attributes
2191  *
2192  */
__audit_mq_open(int oflag,umode_t mode,struct mq_attr * attr)2193 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
2194 {
2195 	struct audit_context *context = audit_context();
2196 
2197 	if (attr)
2198 		memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
2199 	else
2200 		memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2201 
2202 	context->mq_open.oflag = oflag;
2203 	context->mq_open.mode = mode;
2204 
2205 	context->type = AUDIT_MQ_OPEN;
2206 }
2207 
2208 /**
2209  * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2210  * @mqdes: MQ descriptor
2211  * @msg_len: Message length
2212  * @msg_prio: Message priority
2213  * @abs_timeout: Message timeout in absolute time
2214  *
2215  */
__audit_mq_sendrecv(mqd_t mqdes,size_t msg_len,unsigned int msg_prio,const struct timespec64 * abs_timeout)2216 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2217 			const struct timespec64 *abs_timeout)
2218 {
2219 	struct audit_context *context = audit_context();
2220 	struct timespec64 *p = &context->mq_sendrecv.abs_timeout;
2221 
2222 	if (abs_timeout)
2223 		memcpy(p, abs_timeout, sizeof(*p));
2224 	else
2225 		memset(p, 0, sizeof(*p));
2226 
2227 	context->mq_sendrecv.mqdes = mqdes;
2228 	context->mq_sendrecv.msg_len = msg_len;
2229 	context->mq_sendrecv.msg_prio = msg_prio;
2230 
2231 	context->type = AUDIT_MQ_SENDRECV;
2232 }
2233 
2234 /**
2235  * __audit_mq_notify - record audit data for a POSIX MQ notify
2236  * @mqdes: MQ descriptor
2237  * @notification: Notification event
2238  *
2239  */
2240 
__audit_mq_notify(mqd_t mqdes,const struct sigevent * notification)2241 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2242 {
2243 	struct audit_context *context = audit_context();
2244 
2245 	if (notification)
2246 		context->mq_notify.sigev_signo = notification->sigev_signo;
2247 	else
2248 		context->mq_notify.sigev_signo = 0;
2249 
2250 	context->mq_notify.mqdes = mqdes;
2251 	context->type = AUDIT_MQ_NOTIFY;
2252 }
2253 
2254 /**
2255  * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2256  * @mqdes: MQ descriptor
2257  * @mqstat: MQ flags
2258  *
2259  */
__audit_mq_getsetattr(mqd_t mqdes,struct mq_attr * mqstat)2260 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2261 {
2262 	struct audit_context *context = audit_context();
2263 	context->mq_getsetattr.mqdes = mqdes;
2264 	context->mq_getsetattr.mqstat = *mqstat;
2265 	context->type = AUDIT_MQ_GETSETATTR;
2266 }
2267 
2268 /**
2269  * __audit_ipc_obj - record audit data for ipc object
2270  * @ipcp: ipc permissions
2271  *
2272  */
__audit_ipc_obj(struct kern_ipc_perm * ipcp)2273 void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2274 {
2275 	struct audit_context *context = audit_context();
2276 	context->ipc.uid = ipcp->uid;
2277 	context->ipc.gid = ipcp->gid;
2278 	context->ipc.mode = ipcp->mode;
2279 	context->ipc.has_perm = 0;
2280 	security_ipc_getsecid(ipcp, &context->ipc.osid);
2281 	context->type = AUDIT_IPC;
2282 }
2283 
2284 /**
2285  * __audit_ipc_set_perm - record audit data for new ipc permissions
2286  * @qbytes: msgq bytes
2287  * @uid: msgq user id
2288  * @gid: msgq group id
2289  * @mode: msgq mode (permissions)
2290  *
2291  * Called only after audit_ipc_obj().
2292  */
__audit_ipc_set_perm(unsigned long qbytes,uid_t uid,gid_t gid,umode_t mode)2293 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
2294 {
2295 	struct audit_context *context = audit_context();
2296 
2297 	context->ipc.qbytes = qbytes;
2298 	context->ipc.perm_uid = uid;
2299 	context->ipc.perm_gid = gid;
2300 	context->ipc.perm_mode = mode;
2301 	context->ipc.has_perm = 1;
2302 }
2303 
__audit_bprm(struct linux_binprm * bprm)2304 void __audit_bprm(struct linux_binprm *bprm)
2305 {
2306 	struct audit_context *context = audit_context();
2307 
2308 	context->type = AUDIT_EXECVE;
2309 	context->execve.argc = bprm->argc;
2310 }
2311 
2312 
2313 /**
2314  * __audit_socketcall - record audit data for sys_socketcall
2315  * @nargs: number of args, which should not be more than AUDITSC_ARGS.
2316  * @args: args array
2317  *
2318  */
__audit_socketcall(int nargs,unsigned long * args)2319 int __audit_socketcall(int nargs, unsigned long *args)
2320 {
2321 	struct audit_context *context = audit_context();
2322 
2323 	if (nargs <= 0 || nargs > AUDITSC_ARGS || !args)
2324 		return -EINVAL;
2325 	context->type = AUDIT_SOCKETCALL;
2326 	context->socketcall.nargs = nargs;
2327 	memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
2328 	return 0;
2329 }
2330 
2331 /**
2332  * __audit_fd_pair - record audit data for pipe and socketpair
2333  * @fd1: the first file descriptor
2334  * @fd2: the second file descriptor
2335  *
2336  */
__audit_fd_pair(int fd1,int fd2)2337 void __audit_fd_pair(int fd1, int fd2)
2338 {
2339 	struct audit_context *context = audit_context();
2340 	context->fds[0] = fd1;
2341 	context->fds[1] = fd2;
2342 }
2343 
2344 /**
2345  * __audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2346  * @len: data length in user space
2347  * @a: data address in kernel space
2348  *
2349  * Returns 0 for success or NULL context or < 0 on error.
2350  */
__audit_sockaddr(int len,void * a)2351 int __audit_sockaddr(int len, void *a)
2352 {
2353 	struct audit_context *context = audit_context();
2354 
2355 	if (!context->sockaddr) {
2356 		void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
2357 		if (!p)
2358 			return -ENOMEM;
2359 		context->sockaddr = p;
2360 	}
2361 
2362 	context->sockaddr_len = len;
2363 	memcpy(context->sockaddr, a, len);
2364 	return 0;
2365 }
2366 
__audit_ptrace(struct task_struct * t)2367 void __audit_ptrace(struct task_struct *t)
2368 {
2369 	struct audit_context *context = audit_context();
2370 
2371 	context->target_pid = task_tgid_nr(t);
2372 	context->target_auid = audit_get_loginuid(t);
2373 	context->target_uid = task_uid(t);
2374 	context->target_sessionid = audit_get_sessionid(t);
2375 	security_task_getsecid(t, &context->target_sid);
2376 	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
2377 }
2378 
2379 /**
2380  * audit_signal_info_syscall - record signal info for syscalls
2381  * @t: task being signaled
2382  *
2383  * If the audit subsystem is being terminated, record the task (pid)
2384  * and uid that is doing that.
2385  */
audit_signal_info_syscall(struct task_struct * t)2386 int audit_signal_info_syscall(struct task_struct *t)
2387 {
2388 	struct audit_aux_data_pids *axp;
2389 	struct audit_context *ctx = audit_context();
2390 	kuid_t t_uid = task_uid(t);
2391 
2392 	if (!audit_signals || audit_dummy_context())
2393 		return 0;
2394 
2395 	/* optimize the common case by putting first signal recipient directly
2396 	 * in audit_context */
2397 	if (!ctx->target_pid) {
2398 		ctx->target_pid = task_tgid_nr(t);
2399 		ctx->target_auid = audit_get_loginuid(t);
2400 		ctx->target_uid = t_uid;
2401 		ctx->target_sessionid = audit_get_sessionid(t);
2402 		security_task_getsecid(t, &ctx->target_sid);
2403 		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
2404 		return 0;
2405 	}
2406 
2407 	axp = (void *)ctx->aux_pids;
2408 	if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2409 		axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2410 		if (!axp)
2411 			return -ENOMEM;
2412 
2413 		axp->d.type = AUDIT_OBJ_PID;
2414 		axp->d.next = ctx->aux_pids;
2415 		ctx->aux_pids = (void *)axp;
2416 	}
2417 	BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2418 
2419 	axp->target_pid[axp->pid_count] = task_tgid_nr(t);
2420 	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2421 	axp->target_uid[axp->pid_count] = t_uid;
2422 	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2423 	security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2424 	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
2425 	axp->pid_count++;
2426 
2427 	return 0;
2428 }
2429 
2430 /**
2431  * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
2432  * @bprm: pointer to the bprm being processed
2433  * @new: the proposed new credentials
2434  * @old: the old credentials
2435  *
2436  * Simply check if the proc already has the caps given by the file and if not
2437  * store the priv escalation info for later auditing at the end of the syscall
2438  *
2439  * -Eric
2440  */
__audit_log_bprm_fcaps(struct linux_binprm * bprm,const struct cred * new,const struct cred * old)2441 int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
2442 			   const struct cred *new, const struct cred *old)
2443 {
2444 	struct audit_aux_data_bprm_fcaps *ax;
2445 	struct audit_context *context = audit_context();
2446 	struct cpu_vfs_cap_data vcaps;
2447 
2448 	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2449 	if (!ax)
2450 		return -ENOMEM;
2451 
2452 	ax->d.type = AUDIT_BPRM_FCAPS;
2453 	ax->d.next = context->aux;
2454 	context->aux = (void *)ax;
2455 
2456 	get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps);
2457 
2458 	ax->fcap.permitted = vcaps.permitted;
2459 	ax->fcap.inheritable = vcaps.inheritable;
2460 	ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2461 	ax->fcap.rootid = vcaps.rootid;
2462 	ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
2463 
2464 	ax->old_pcap.permitted   = old->cap_permitted;
2465 	ax->old_pcap.inheritable = old->cap_inheritable;
2466 	ax->old_pcap.effective   = old->cap_effective;
2467 	ax->old_pcap.ambient     = old->cap_ambient;
2468 
2469 	ax->new_pcap.permitted   = new->cap_permitted;
2470 	ax->new_pcap.inheritable = new->cap_inheritable;
2471 	ax->new_pcap.effective   = new->cap_effective;
2472 	ax->new_pcap.ambient     = new->cap_ambient;
2473 	return 0;
2474 }
2475 
2476 /**
2477  * __audit_log_capset - store information about the arguments to the capset syscall
2478  * @new: the new credentials
2479  * @old: the old (current) credentials
2480  *
2481  * Record the arguments userspace sent to sys_capset for later printing by the
2482  * audit system if applicable
2483  */
__audit_log_capset(const struct cred * new,const struct cred * old)2484 void __audit_log_capset(const struct cred *new, const struct cred *old)
2485 {
2486 	struct audit_context *context = audit_context();
2487 	context->capset.pid = task_tgid_nr(current);
2488 	context->capset.cap.effective   = new->cap_effective;
2489 	context->capset.cap.inheritable = new->cap_effective;
2490 	context->capset.cap.permitted   = new->cap_permitted;
2491 	context->capset.cap.ambient     = new->cap_ambient;
2492 	context->type = AUDIT_CAPSET;
2493 }
2494 
__audit_mmap_fd(int fd,int flags)2495 void __audit_mmap_fd(int fd, int flags)
2496 {
2497 	struct audit_context *context = audit_context();
2498 	context->mmap.fd = fd;
2499 	context->mmap.flags = flags;
2500 	context->type = AUDIT_MMAP;
2501 }
2502 
__audit_log_kern_module(char * name)2503 void __audit_log_kern_module(char *name)
2504 {
2505 	struct audit_context *context = audit_context();
2506 
2507 	context->module.name = kstrdup(name, GFP_KERNEL);
2508 	if (!context->module.name)
2509 		audit_log_lost("out of memory in __audit_log_kern_module");
2510 	context->type = AUDIT_KERN_MODULE;
2511 }
2512 
__audit_fanotify(unsigned int response)2513 void __audit_fanotify(unsigned int response)
2514 {
2515 	audit_log(audit_context(), GFP_KERNEL,
2516 		AUDIT_FANOTIFY,	"resp=%u", response);
2517 }
2518 
__audit_tk_injoffset(struct timespec64 offset)2519 void __audit_tk_injoffset(struct timespec64 offset)
2520 {
2521 	audit_log(audit_context(), GFP_KERNEL, AUDIT_TIME_INJOFFSET,
2522 		  "sec=%lli nsec=%li",
2523 		  (long long)offset.tv_sec, offset.tv_nsec);
2524 }
2525 
audit_log_ntp_val(const struct audit_ntp_data * ad,const char * op,enum audit_ntp_type type)2526 static void audit_log_ntp_val(const struct audit_ntp_data *ad,
2527 			      const char *op, enum audit_ntp_type type)
2528 {
2529 	const struct audit_ntp_val *val = &ad->vals[type];
2530 
2531 	if (val->newval == val->oldval)
2532 		return;
2533 
2534 	audit_log(audit_context(), GFP_KERNEL, AUDIT_TIME_ADJNTPVAL,
2535 		  "op=%s old=%lli new=%lli", op, val->oldval, val->newval);
2536 }
2537 
__audit_ntp_log(const struct audit_ntp_data * ad)2538 void __audit_ntp_log(const struct audit_ntp_data *ad)
2539 {
2540 	audit_log_ntp_val(ad, "offset",	AUDIT_NTP_OFFSET);
2541 	audit_log_ntp_val(ad, "freq",	AUDIT_NTP_FREQ);
2542 	audit_log_ntp_val(ad, "status",	AUDIT_NTP_STATUS);
2543 	audit_log_ntp_val(ad, "tai",	AUDIT_NTP_TAI);
2544 	audit_log_ntp_val(ad, "tick",	AUDIT_NTP_TICK);
2545 	audit_log_ntp_val(ad, "adjust",	AUDIT_NTP_ADJUST);
2546 }
2547 
audit_log_task(struct audit_buffer * ab)2548 static void audit_log_task(struct audit_buffer *ab)
2549 {
2550 	kuid_t auid, uid;
2551 	kgid_t gid;
2552 	unsigned int sessionid;
2553 	char comm[sizeof(current->comm)];
2554 
2555 	auid = audit_get_loginuid(current);
2556 	sessionid = audit_get_sessionid(current);
2557 	current_uid_gid(&uid, &gid);
2558 
2559 	audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2560 			 from_kuid(&init_user_ns, auid),
2561 			 from_kuid(&init_user_ns, uid),
2562 			 from_kgid(&init_user_ns, gid),
2563 			 sessionid);
2564 	audit_log_task_context(ab);
2565 	audit_log_format(ab, " pid=%d comm=", task_tgid_nr(current));
2566 	audit_log_untrustedstring(ab, get_task_comm(comm, current));
2567 	audit_log_d_path_exe(ab, current->mm);
2568 }
2569 
2570 /**
2571  * audit_core_dumps - record information about processes that end abnormally
2572  * @signr: signal value
2573  *
2574  * If a process ends with a core dump, something fishy is going on and we
2575  * should record the event for investigation.
2576  */
audit_core_dumps(long signr)2577 void audit_core_dumps(long signr)
2578 {
2579 	struct audit_buffer *ab;
2580 
2581 	if (!audit_enabled)
2582 		return;
2583 
2584 	if (signr == SIGQUIT)	/* don't care for those */
2585 		return;
2586 
2587 	ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_ANOM_ABEND);
2588 	if (unlikely(!ab))
2589 		return;
2590 	audit_log_task(ab);
2591 	audit_log_format(ab, " sig=%ld res=1", signr);
2592 	audit_log_end(ab);
2593 }
2594 
2595 /**
2596  * audit_seccomp - record information about a seccomp action
2597  * @syscall: syscall number
2598  * @signr: signal value
2599  * @code: the seccomp action
2600  *
2601  * Record the information associated with a seccomp action. Event filtering for
2602  * seccomp actions that are not to be logged is done in seccomp_log().
2603  * Therefore, this function forces auditing independent of the audit_enabled
2604  * and dummy context state because seccomp actions should be logged even when
2605  * audit is not in use.
2606  */
audit_seccomp(unsigned long syscall,long signr,int code)2607 void audit_seccomp(unsigned long syscall, long signr, int code)
2608 {
2609 	struct audit_buffer *ab;
2610 
2611 	ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_SECCOMP);
2612 	if (unlikely(!ab))
2613 		return;
2614 	audit_log_task(ab);
2615 	audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x",
2616 			 signr, syscall_get_arch(current), syscall,
2617 			 in_compat_syscall(), KSTK_EIP(current), code);
2618 	audit_log_end(ab);
2619 }
2620 
audit_seccomp_actions_logged(const char * names,const char * old_names,int res)2621 void audit_seccomp_actions_logged(const char *names, const char *old_names,
2622 				  int res)
2623 {
2624 	struct audit_buffer *ab;
2625 
2626 	if (!audit_enabled)
2627 		return;
2628 
2629 	ab = audit_log_start(audit_context(), GFP_KERNEL,
2630 			     AUDIT_CONFIG_CHANGE);
2631 	if (unlikely(!ab))
2632 		return;
2633 
2634 	audit_log_format(ab,
2635 			 "op=seccomp-logging actions=%s old-actions=%s res=%d",
2636 			 names, old_names, res);
2637 	audit_log_end(ab);
2638 }
2639 
audit_killed_trees(void)2640 struct list_head *audit_killed_trees(void)
2641 {
2642 	struct audit_context *ctx = audit_context();
2643 	if (likely(!ctx || !ctx->in_syscall))
2644 		return NULL;
2645 	return &ctx->killed_trees;
2646 }
2647