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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 #include <uapi/linux/netfilter/nf_tables.h>
79 
80 #include "audit.h"
81 
82 /* flags stating the success for a syscall */
83 #define AUDITSC_INVALID 0
84 #define AUDITSC_SUCCESS 1
85 #define AUDITSC_FAILURE 2
86 
87 /* no execve audit message should be longer than this (userspace limits),
88  * see the note near the top of audit_log_execve_info() about this value */
89 #define MAX_EXECVE_AUDIT_LEN 7500
90 
91 /* max length to print of cmdline/proctitle value during audit */
92 #define MAX_PROCTITLE_AUDIT_LEN 128
93 
94 /* number of audit rules */
95 int audit_n_rules;
96 
97 /* determines whether we collect data for signals sent */
98 int audit_signals;
99 
100 struct audit_aux_data {
101 	struct audit_aux_data	*next;
102 	int			type;
103 };
104 
105 #define AUDIT_AUX_IPCPERM	0
106 
107 /* Number of target pids per aux struct. */
108 #define AUDIT_AUX_PIDS	16
109 
110 struct audit_aux_data_pids {
111 	struct audit_aux_data	d;
112 	pid_t			target_pid[AUDIT_AUX_PIDS];
113 	kuid_t			target_auid[AUDIT_AUX_PIDS];
114 	kuid_t			target_uid[AUDIT_AUX_PIDS];
115 	unsigned int		target_sessionid[AUDIT_AUX_PIDS];
116 	u32			target_sid[AUDIT_AUX_PIDS];
117 	char 			target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
118 	int			pid_count;
119 };
120 
121 struct audit_aux_data_bprm_fcaps {
122 	struct audit_aux_data	d;
123 	struct audit_cap_data	fcap;
124 	unsigned int		fcap_ver;
125 	struct audit_cap_data	old_pcap;
126 	struct audit_cap_data	new_pcap;
127 };
128 
129 struct audit_tree_refs {
130 	struct audit_tree_refs *next;
131 	struct audit_chunk *c[31];
132 };
133 
134 struct audit_nfcfgop_tab {
135 	enum audit_nfcfgop	op;
136 	const char		*s;
137 };
138 
139 static const struct audit_nfcfgop_tab audit_nfcfgs[] = {
140 	{ AUDIT_XT_OP_REGISTER,			"xt_register"		   },
141 	{ AUDIT_XT_OP_REPLACE,			"xt_replace"		   },
142 	{ AUDIT_XT_OP_UNREGISTER,		"xt_unregister"		   },
143 	{ AUDIT_NFT_OP_TABLE_REGISTER,		"nft_register_table"	   },
144 	{ AUDIT_NFT_OP_TABLE_UNREGISTER,	"nft_unregister_table"	   },
145 	{ AUDIT_NFT_OP_CHAIN_REGISTER,		"nft_register_chain"	   },
146 	{ AUDIT_NFT_OP_CHAIN_UNREGISTER,	"nft_unregister_chain"	   },
147 	{ AUDIT_NFT_OP_RULE_REGISTER,		"nft_register_rule"	   },
148 	{ AUDIT_NFT_OP_RULE_UNREGISTER,		"nft_unregister_rule"	   },
149 	{ AUDIT_NFT_OP_SET_REGISTER,		"nft_register_set"	   },
150 	{ AUDIT_NFT_OP_SET_UNREGISTER,		"nft_unregister_set"	   },
151 	{ AUDIT_NFT_OP_SETELEM_REGISTER,	"nft_register_setelem"	   },
152 	{ AUDIT_NFT_OP_SETELEM_UNREGISTER,	"nft_unregister_setelem"   },
153 	{ AUDIT_NFT_OP_GEN_REGISTER,		"nft_register_gen"	   },
154 	{ AUDIT_NFT_OP_OBJ_REGISTER,		"nft_register_obj"	   },
155 	{ AUDIT_NFT_OP_OBJ_UNREGISTER,		"nft_unregister_obj"	   },
156 	{ AUDIT_NFT_OP_OBJ_RESET,		"nft_reset_obj"		   },
157 	{ AUDIT_NFT_OP_FLOWTABLE_REGISTER,	"nft_register_flowtable"   },
158 	{ AUDIT_NFT_OP_FLOWTABLE_UNREGISTER,	"nft_unregister_flowtable" },
159 	{ AUDIT_NFT_OP_INVALID,			"nft_invalid"		   },
160 };
161 
audit_match_perm(struct audit_context * ctx,int mask)162 static int audit_match_perm(struct audit_context *ctx, int mask)
163 {
164 	unsigned n;
165 	if (unlikely(!ctx))
166 		return 0;
167 	n = ctx->major;
168 
169 	switch (audit_classify_syscall(ctx->arch, n)) {
170 	case 0:	/* native */
171 		if ((mask & AUDIT_PERM_WRITE) &&
172 		     audit_match_class(AUDIT_CLASS_WRITE, n))
173 			return 1;
174 		if ((mask & AUDIT_PERM_READ) &&
175 		     audit_match_class(AUDIT_CLASS_READ, n))
176 			return 1;
177 		if ((mask & AUDIT_PERM_ATTR) &&
178 		     audit_match_class(AUDIT_CLASS_CHATTR, n))
179 			return 1;
180 		return 0;
181 	case 1: /* 32bit on biarch */
182 		if ((mask & AUDIT_PERM_WRITE) &&
183 		     audit_match_class(AUDIT_CLASS_WRITE_32, n))
184 			return 1;
185 		if ((mask & AUDIT_PERM_READ) &&
186 		     audit_match_class(AUDIT_CLASS_READ_32, n))
187 			return 1;
188 		if ((mask & AUDIT_PERM_ATTR) &&
189 		     audit_match_class(AUDIT_CLASS_CHATTR_32, n))
190 			return 1;
191 		return 0;
192 	case 2: /* open */
193 		return mask & ACC_MODE(ctx->argv[1]);
194 	case 3: /* openat */
195 		return mask & ACC_MODE(ctx->argv[2]);
196 	case 4: /* socketcall */
197 		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
198 	case 5: /* execve */
199 		return mask & AUDIT_PERM_EXEC;
200 	default:
201 		return 0;
202 	}
203 }
204 
audit_match_filetype(struct audit_context * ctx,int val)205 static int audit_match_filetype(struct audit_context *ctx, int val)
206 {
207 	struct audit_names *n;
208 	umode_t mode = (umode_t)val;
209 
210 	if (unlikely(!ctx))
211 		return 0;
212 
213 	list_for_each_entry(n, &ctx->names_list, list) {
214 		if ((n->ino != AUDIT_INO_UNSET) &&
215 		    ((n->mode & S_IFMT) == mode))
216 			return 1;
217 	}
218 
219 	return 0;
220 }
221 
222 /*
223  * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
224  * ->first_trees points to its beginning, ->trees - to the current end of data.
225  * ->tree_count is the number of free entries in array pointed to by ->trees.
226  * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
227  * "empty" becomes (p, p, 31) afterwards.  We don't shrink the list (and seriously,
228  * it's going to remain 1-element for almost any setup) until we free context itself.
229  * References in it _are_ dropped - at the same time we free/drop aux stuff.
230  */
231 
audit_set_auditable(struct audit_context * ctx)232 static void audit_set_auditable(struct audit_context *ctx)
233 {
234 	if (!ctx->prio) {
235 		ctx->prio = 1;
236 		ctx->current_state = AUDIT_RECORD_CONTEXT;
237 	}
238 }
239 
put_tree_ref(struct audit_context * ctx,struct audit_chunk * chunk)240 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
241 {
242 	struct audit_tree_refs *p = ctx->trees;
243 	int left = ctx->tree_count;
244 	if (likely(left)) {
245 		p->c[--left] = chunk;
246 		ctx->tree_count = left;
247 		return 1;
248 	}
249 	if (!p)
250 		return 0;
251 	p = p->next;
252 	if (p) {
253 		p->c[30] = chunk;
254 		ctx->trees = p;
255 		ctx->tree_count = 30;
256 		return 1;
257 	}
258 	return 0;
259 }
260 
grow_tree_refs(struct audit_context * ctx)261 static int grow_tree_refs(struct audit_context *ctx)
262 {
263 	struct audit_tree_refs *p = ctx->trees;
264 	ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
265 	if (!ctx->trees) {
266 		ctx->trees = p;
267 		return 0;
268 	}
269 	if (p)
270 		p->next = ctx->trees;
271 	else
272 		ctx->first_trees = ctx->trees;
273 	ctx->tree_count = 31;
274 	return 1;
275 }
276 
unroll_tree_refs(struct audit_context * ctx,struct audit_tree_refs * p,int count)277 static void unroll_tree_refs(struct audit_context *ctx,
278 		      struct audit_tree_refs *p, int count)
279 {
280 	struct audit_tree_refs *q;
281 	int n;
282 	if (!p) {
283 		/* we started with empty chain */
284 		p = ctx->first_trees;
285 		count = 31;
286 		/* if the very first allocation has failed, nothing to do */
287 		if (!p)
288 			return;
289 	}
290 	n = count;
291 	for (q = p; q != ctx->trees; q = q->next, n = 31) {
292 		while (n--) {
293 			audit_put_chunk(q->c[n]);
294 			q->c[n] = NULL;
295 		}
296 	}
297 	while (n-- > ctx->tree_count) {
298 		audit_put_chunk(q->c[n]);
299 		q->c[n] = NULL;
300 	}
301 	ctx->trees = p;
302 	ctx->tree_count = count;
303 }
304 
free_tree_refs(struct audit_context * ctx)305 static void free_tree_refs(struct audit_context *ctx)
306 {
307 	struct audit_tree_refs *p, *q;
308 	for (p = ctx->first_trees; p; p = q) {
309 		q = p->next;
310 		kfree(p);
311 	}
312 }
313 
match_tree_refs(struct audit_context * ctx,struct audit_tree * tree)314 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
315 {
316 	struct audit_tree_refs *p;
317 	int n;
318 	if (!tree)
319 		return 0;
320 	/* full ones */
321 	for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
322 		for (n = 0; n < 31; n++)
323 			if (audit_tree_match(p->c[n], tree))
324 				return 1;
325 	}
326 	/* partial */
327 	if (p) {
328 		for (n = ctx->tree_count; n < 31; n++)
329 			if (audit_tree_match(p->c[n], tree))
330 				return 1;
331 	}
332 	return 0;
333 }
334 
audit_compare_uid(kuid_t uid,struct audit_names * name,struct audit_field * f,struct audit_context * ctx)335 static int audit_compare_uid(kuid_t uid,
336 			     struct audit_names *name,
337 			     struct audit_field *f,
338 			     struct audit_context *ctx)
339 {
340 	struct audit_names *n;
341 	int rc;
342 
343 	if (name) {
344 		rc = audit_uid_comparator(uid, f->op, name->uid);
345 		if (rc)
346 			return rc;
347 	}
348 
349 	if (ctx) {
350 		list_for_each_entry(n, &ctx->names_list, list) {
351 			rc = audit_uid_comparator(uid, f->op, n->uid);
352 			if (rc)
353 				return rc;
354 		}
355 	}
356 	return 0;
357 }
358 
audit_compare_gid(kgid_t gid,struct audit_names * name,struct audit_field * f,struct audit_context * ctx)359 static int audit_compare_gid(kgid_t gid,
360 			     struct audit_names *name,
361 			     struct audit_field *f,
362 			     struct audit_context *ctx)
363 {
364 	struct audit_names *n;
365 	int rc;
366 
367 	if (name) {
368 		rc = audit_gid_comparator(gid, f->op, name->gid);
369 		if (rc)
370 			return rc;
371 	}
372 
373 	if (ctx) {
374 		list_for_each_entry(n, &ctx->names_list, list) {
375 			rc = audit_gid_comparator(gid, f->op, n->gid);
376 			if (rc)
377 				return rc;
378 		}
379 	}
380 	return 0;
381 }
382 
audit_field_compare(struct task_struct * tsk,const struct cred * cred,struct audit_field * f,struct audit_context * ctx,struct audit_names * name)383 static int audit_field_compare(struct task_struct *tsk,
384 			       const struct cred *cred,
385 			       struct audit_field *f,
386 			       struct audit_context *ctx,
387 			       struct audit_names *name)
388 {
389 	switch (f->val) {
390 	/* process to file object comparisons */
391 	case AUDIT_COMPARE_UID_TO_OBJ_UID:
392 		return audit_compare_uid(cred->uid, name, f, ctx);
393 	case AUDIT_COMPARE_GID_TO_OBJ_GID:
394 		return audit_compare_gid(cred->gid, name, f, ctx);
395 	case AUDIT_COMPARE_EUID_TO_OBJ_UID:
396 		return audit_compare_uid(cred->euid, name, f, ctx);
397 	case AUDIT_COMPARE_EGID_TO_OBJ_GID:
398 		return audit_compare_gid(cred->egid, name, f, ctx);
399 	case AUDIT_COMPARE_AUID_TO_OBJ_UID:
400 		return audit_compare_uid(audit_get_loginuid(tsk), name, f, ctx);
401 	case AUDIT_COMPARE_SUID_TO_OBJ_UID:
402 		return audit_compare_uid(cred->suid, name, f, ctx);
403 	case AUDIT_COMPARE_SGID_TO_OBJ_GID:
404 		return audit_compare_gid(cred->sgid, name, f, ctx);
405 	case AUDIT_COMPARE_FSUID_TO_OBJ_UID:
406 		return audit_compare_uid(cred->fsuid, name, f, ctx);
407 	case AUDIT_COMPARE_FSGID_TO_OBJ_GID:
408 		return audit_compare_gid(cred->fsgid, name, f, ctx);
409 	/* uid comparisons */
410 	case AUDIT_COMPARE_UID_TO_AUID:
411 		return audit_uid_comparator(cred->uid, f->op,
412 					    audit_get_loginuid(tsk));
413 	case AUDIT_COMPARE_UID_TO_EUID:
414 		return audit_uid_comparator(cred->uid, f->op, cred->euid);
415 	case AUDIT_COMPARE_UID_TO_SUID:
416 		return audit_uid_comparator(cred->uid, f->op, cred->suid);
417 	case AUDIT_COMPARE_UID_TO_FSUID:
418 		return audit_uid_comparator(cred->uid, f->op, cred->fsuid);
419 	/* auid comparisons */
420 	case AUDIT_COMPARE_AUID_TO_EUID:
421 		return audit_uid_comparator(audit_get_loginuid(tsk), f->op,
422 					    cred->euid);
423 	case AUDIT_COMPARE_AUID_TO_SUID:
424 		return audit_uid_comparator(audit_get_loginuid(tsk), f->op,
425 					    cred->suid);
426 	case AUDIT_COMPARE_AUID_TO_FSUID:
427 		return audit_uid_comparator(audit_get_loginuid(tsk), f->op,
428 					    cred->fsuid);
429 	/* euid comparisons */
430 	case AUDIT_COMPARE_EUID_TO_SUID:
431 		return audit_uid_comparator(cred->euid, f->op, cred->suid);
432 	case AUDIT_COMPARE_EUID_TO_FSUID:
433 		return audit_uid_comparator(cred->euid, f->op, cred->fsuid);
434 	/* suid comparisons */
435 	case AUDIT_COMPARE_SUID_TO_FSUID:
436 		return audit_uid_comparator(cred->suid, f->op, cred->fsuid);
437 	/* gid comparisons */
438 	case AUDIT_COMPARE_GID_TO_EGID:
439 		return audit_gid_comparator(cred->gid, f->op, cred->egid);
440 	case AUDIT_COMPARE_GID_TO_SGID:
441 		return audit_gid_comparator(cred->gid, f->op, cred->sgid);
442 	case AUDIT_COMPARE_GID_TO_FSGID:
443 		return audit_gid_comparator(cred->gid, f->op, cred->fsgid);
444 	/* egid comparisons */
445 	case AUDIT_COMPARE_EGID_TO_SGID:
446 		return audit_gid_comparator(cred->egid, f->op, cred->sgid);
447 	case AUDIT_COMPARE_EGID_TO_FSGID:
448 		return audit_gid_comparator(cred->egid, f->op, cred->fsgid);
449 	/* sgid comparison */
450 	case AUDIT_COMPARE_SGID_TO_FSGID:
451 		return audit_gid_comparator(cred->sgid, f->op, cred->fsgid);
452 	default:
453 		WARN(1, "Missing AUDIT_COMPARE define.  Report as a bug\n");
454 		return 0;
455 	}
456 	return 0;
457 }
458 
459 /* Determine if any context name data matches a rule's watch data */
460 /* Compare a task_struct with an audit_rule.  Return 1 on match, 0
461  * otherwise.
462  *
463  * If task_creation is true, this is an explicit indication that we are
464  * filtering a task rule at task creation time.  This and tsk == current are
465  * the only situations where tsk->cred may be accessed without an rcu read lock.
466  */
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)467 static int audit_filter_rules(struct task_struct *tsk,
468 			      struct audit_krule *rule,
469 			      struct audit_context *ctx,
470 			      struct audit_names *name,
471 			      enum audit_state *state,
472 			      bool task_creation)
473 {
474 	const struct cred *cred;
475 	int i, need_sid = 1;
476 	u32 sid;
477 	unsigned int sessionid;
478 
479 	cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);
480 
481 	for (i = 0; i < rule->field_count; i++) {
482 		struct audit_field *f = &rule->fields[i];
483 		struct audit_names *n;
484 		int result = 0;
485 		pid_t pid;
486 
487 		switch (f->type) {
488 		case AUDIT_PID:
489 			pid = task_tgid_nr(tsk);
490 			result = audit_comparator(pid, f->op, f->val);
491 			break;
492 		case AUDIT_PPID:
493 			if (ctx) {
494 				if (!ctx->ppid)
495 					ctx->ppid = task_ppid_nr(tsk);
496 				result = audit_comparator(ctx->ppid, f->op, f->val);
497 			}
498 			break;
499 		case AUDIT_EXE:
500 			result = audit_exe_compare(tsk, rule->exe);
501 			if (f->op == Audit_not_equal)
502 				result = !result;
503 			break;
504 		case AUDIT_UID:
505 			result = audit_uid_comparator(cred->uid, f->op, f->uid);
506 			break;
507 		case AUDIT_EUID:
508 			result = audit_uid_comparator(cred->euid, f->op, f->uid);
509 			break;
510 		case AUDIT_SUID:
511 			result = audit_uid_comparator(cred->suid, f->op, f->uid);
512 			break;
513 		case AUDIT_FSUID:
514 			result = audit_uid_comparator(cred->fsuid, f->op, f->uid);
515 			break;
516 		case AUDIT_GID:
517 			result = audit_gid_comparator(cred->gid, f->op, f->gid);
518 			if (f->op == Audit_equal) {
519 				if (!result)
520 					result = groups_search(cred->group_info, f->gid);
521 			} else if (f->op == Audit_not_equal) {
522 				if (result)
523 					result = !groups_search(cred->group_info, f->gid);
524 			}
525 			break;
526 		case AUDIT_EGID:
527 			result = audit_gid_comparator(cred->egid, f->op, f->gid);
528 			if (f->op == Audit_equal) {
529 				if (!result)
530 					result = groups_search(cred->group_info, f->gid);
531 			} else if (f->op == Audit_not_equal) {
532 				if (result)
533 					result = !groups_search(cred->group_info, f->gid);
534 			}
535 			break;
536 		case AUDIT_SGID:
537 			result = audit_gid_comparator(cred->sgid, f->op, f->gid);
538 			break;
539 		case AUDIT_FSGID:
540 			result = audit_gid_comparator(cred->fsgid, f->op, f->gid);
541 			break;
542 		case AUDIT_SESSIONID:
543 			sessionid = audit_get_sessionid(tsk);
544 			result = audit_comparator(sessionid, f->op, f->val);
545 			break;
546 		case AUDIT_PERS:
547 			result = audit_comparator(tsk->personality, f->op, f->val);
548 			break;
549 		case AUDIT_ARCH:
550 			if (ctx)
551 				result = audit_comparator(ctx->arch, f->op, f->val);
552 			break;
553 
554 		case AUDIT_EXIT:
555 			if (ctx && ctx->return_valid)
556 				result = audit_comparator(ctx->return_code, f->op, f->val);
557 			break;
558 		case AUDIT_SUCCESS:
559 			if (ctx && ctx->return_valid) {
560 				if (f->val)
561 					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
562 				else
563 					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
564 			}
565 			break;
566 		case AUDIT_DEVMAJOR:
567 			if (name) {
568 				if (audit_comparator(MAJOR(name->dev), f->op, f->val) ||
569 				    audit_comparator(MAJOR(name->rdev), f->op, f->val))
570 					++result;
571 			} else if (ctx) {
572 				list_for_each_entry(n, &ctx->names_list, list) {
573 					if (audit_comparator(MAJOR(n->dev), f->op, f->val) ||
574 					    audit_comparator(MAJOR(n->rdev), f->op, f->val)) {
575 						++result;
576 						break;
577 					}
578 				}
579 			}
580 			break;
581 		case AUDIT_DEVMINOR:
582 			if (name) {
583 				if (audit_comparator(MINOR(name->dev), f->op, f->val) ||
584 				    audit_comparator(MINOR(name->rdev), f->op, f->val))
585 					++result;
586 			} else if (ctx) {
587 				list_for_each_entry(n, &ctx->names_list, list) {
588 					if (audit_comparator(MINOR(n->dev), f->op, f->val) ||
589 					    audit_comparator(MINOR(n->rdev), f->op, f->val)) {
590 						++result;
591 						break;
592 					}
593 				}
594 			}
595 			break;
596 		case AUDIT_INODE:
597 			if (name)
598 				result = audit_comparator(name->ino, f->op, f->val);
599 			else if (ctx) {
600 				list_for_each_entry(n, &ctx->names_list, list) {
601 					if (audit_comparator(n->ino, f->op, f->val)) {
602 						++result;
603 						break;
604 					}
605 				}
606 			}
607 			break;
608 		case AUDIT_OBJ_UID:
609 			if (name) {
610 				result = audit_uid_comparator(name->uid, f->op, f->uid);
611 			} else if (ctx) {
612 				list_for_each_entry(n, &ctx->names_list, list) {
613 					if (audit_uid_comparator(n->uid, f->op, f->uid)) {
614 						++result;
615 						break;
616 					}
617 				}
618 			}
619 			break;
620 		case AUDIT_OBJ_GID:
621 			if (name) {
622 				result = audit_gid_comparator(name->gid, f->op, f->gid);
623 			} else if (ctx) {
624 				list_for_each_entry(n, &ctx->names_list, list) {
625 					if (audit_gid_comparator(n->gid, f->op, f->gid)) {
626 						++result;
627 						break;
628 					}
629 				}
630 			}
631 			break;
632 		case AUDIT_WATCH:
633 			if (name) {
634 				result = audit_watch_compare(rule->watch,
635 							     name->ino,
636 							     name->dev);
637 				if (f->op == Audit_not_equal)
638 					result = !result;
639 			}
640 			break;
641 		case AUDIT_DIR:
642 			if (ctx) {
643 				result = match_tree_refs(ctx, rule->tree);
644 				if (f->op == Audit_not_equal)
645 					result = !result;
646 			}
647 			break;
648 		case AUDIT_LOGINUID:
649 			result = audit_uid_comparator(audit_get_loginuid(tsk),
650 						      f->op, f->uid);
651 			break;
652 		case AUDIT_LOGINUID_SET:
653 			result = audit_comparator(audit_loginuid_set(tsk), f->op, f->val);
654 			break;
655 		case AUDIT_SADDR_FAM:
656 			if (ctx && ctx->sockaddr)
657 				result = audit_comparator(ctx->sockaddr->ss_family,
658 							  f->op, f->val);
659 			break;
660 		case AUDIT_SUBJ_USER:
661 		case AUDIT_SUBJ_ROLE:
662 		case AUDIT_SUBJ_TYPE:
663 		case AUDIT_SUBJ_SEN:
664 		case AUDIT_SUBJ_CLR:
665 			/* NOTE: this may return negative values indicating
666 			   a temporary error.  We simply treat this as a
667 			   match for now to avoid losing information that
668 			   may be wanted.   An error message will also be
669 			   logged upon error */
670 			if (f->lsm_rule) {
671 				if (need_sid) {
672 					security_task_getsecid(tsk, &sid);
673 					need_sid = 0;
674 				}
675 				result = security_audit_rule_match(sid, f->type,
676 								   f->op,
677 								   f->lsm_rule);
678 			}
679 			break;
680 		case AUDIT_OBJ_USER:
681 		case AUDIT_OBJ_ROLE:
682 		case AUDIT_OBJ_TYPE:
683 		case AUDIT_OBJ_LEV_LOW:
684 		case AUDIT_OBJ_LEV_HIGH:
685 			/* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
686 			   also applies here */
687 			if (f->lsm_rule) {
688 				/* Find files that match */
689 				if (name) {
690 					result = security_audit_rule_match(
691 								name->osid,
692 								f->type,
693 								f->op,
694 								f->lsm_rule);
695 				} else if (ctx) {
696 					list_for_each_entry(n, &ctx->names_list, list) {
697 						if (security_audit_rule_match(
698 								n->osid,
699 								f->type,
700 								f->op,
701 								f->lsm_rule)) {
702 							++result;
703 							break;
704 						}
705 					}
706 				}
707 				/* Find ipc objects that match */
708 				if (!ctx || ctx->type != AUDIT_IPC)
709 					break;
710 				if (security_audit_rule_match(ctx->ipc.osid,
711 							      f->type, f->op,
712 							      f->lsm_rule))
713 					++result;
714 			}
715 			break;
716 		case AUDIT_ARG0:
717 		case AUDIT_ARG1:
718 		case AUDIT_ARG2:
719 		case AUDIT_ARG3:
720 			if (ctx)
721 				result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
722 			break;
723 		case AUDIT_FILTERKEY:
724 			/* ignore this field for filtering */
725 			result = 1;
726 			break;
727 		case AUDIT_PERM:
728 			result = audit_match_perm(ctx, f->val);
729 			if (f->op == Audit_not_equal)
730 				result = !result;
731 			break;
732 		case AUDIT_FILETYPE:
733 			result = audit_match_filetype(ctx, f->val);
734 			if (f->op == Audit_not_equal)
735 				result = !result;
736 			break;
737 		case AUDIT_FIELD_COMPARE:
738 			result = audit_field_compare(tsk, cred, f, ctx, name);
739 			break;
740 		}
741 		if (!result)
742 			return 0;
743 	}
744 
745 	if (ctx) {
746 		if (rule->prio <= ctx->prio)
747 			return 0;
748 		if (rule->filterkey) {
749 			kfree(ctx->filterkey);
750 			ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
751 		}
752 		ctx->prio = rule->prio;
753 	}
754 	switch (rule->action) {
755 	case AUDIT_NEVER:
756 		*state = AUDIT_DISABLED;
757 		break;
758 	case AUDIT_ALWAYS:
759 		*state = AUDIT_RECORD_CONTEXT;
760 		break;
761 	}
762 	return 1;
763 }
764 
765 /* At process creation time, we can determine if system-call auditing is
766  * completely disabled for this task.  Since we only have the task
767  * structure at this point, we can only check uid and gid.
768  */
audit_filter_task(struct task_struct * tsk,char ** key)769 static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
770 {
771 	struct audit_entry *e;
772 	enum audit_state   state;
773 
774 	rcu_read_lock();
775 	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
776 		if (audit_filter_rules(tsk, &e->rule, NULL, NULL,
777 				       &state, true)) {
778 			if (state == AUDIT_RECORD_CONTEXT)
779 				*key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
780 			rcu_read_unlock();
781 			return state;
782 		}
783 	}
784 	rcu_read_unlock();
785 	return AUDIT_BUILD_CONTEXT;
786 }
787 
audit_in_mask(const struct audit_krule * rule,unsigned long val)788 static int audit_in_mask(const struct audit_krule *rule, unsigned long val)
789 {
790 	int word, bit;
791 
792 	if (val > 0xffffffff)
793 		return false;
794 
795 	word = AUDIT_WORD(val);
796 	if (word >= AUDIT_BITMASK_SIZE)
797 		return false;
798 
799 	bit = AUDIT_BIT(val);
800 
801 	return rule->mask[word] & bit;
802 }
803 
804 /* At syscall entry and exit time, this filter is called if the
805  * audit_state is not low enough that auditing cannot take place, but is
806  * also not high enough that we already know we have to write an audit
807  * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
808  */
audit_filter_syscall(struct task_struct * tsk,struct audit_context * ctx,struct list_head * list)809 static enum audit_state audit_filter_syscall(struct task_struct *tsk,
810 					     struct audit_context *ctx,
811 					     struct list_head *list)
812 {
813 	struct audit_entry *e;
814 	enum audit_state state;
815 
816 	if (auditd_test_task(tsk))
817 		return AUDIT_DISABLED;
818 
819 	rcu_read_lock();
820 	list_for_each_entry_rcu(e, list, list) {
821 		if (audit_in_mask(&e->rule, ctx->major) &&
822 		    audit_filter_rules(tsk, &e->rule, ctx, NULL,
823 				       &state, false)) {
824 			rcu_read_unlock();
825 			ctx->current_state = state;
826 			return state;
827 		}
828 	}
829 	rcu_read_unlock();
830 	return AUDIT_BUILD_CONTEXT;
831 }
832 
833 /*
834  * Given an audit_name check the inode hash table to see if they match.
835  * Called holding the rcu read lock to protect the use of audit_inode_hash
836  */
audit_filter_inode_name(struct task_struct * tsk,struct audit_names * n,struct audit_context * ctx)837 static int audit_filter_inode_name(struct task_struct *tsk,
838 				   struct audit_names *n,
839 				   struct audit_context *ctx) {
840 	int h = audit_hash_ino((u32)n->ino);
841 	struct list_head *list = &audit_inode_hash[h];
842 	struct audit_entry *e;
843 	enum audit_state state;
844 
845 	list_for_each_entry_rcu(e, list, list) {
846 		if (audit_in_mask(&e->rule, ctx->major) &&
847 		    audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) {
848 			ctx->current_state = state;
849 			return 1;
850 		}
851 	}
852 	return 0;
853 }
854 
855 /* At syscall exit time, this filter is called if any audit_names have been
856  * collected during syscall processing.  We only check rules in sublists at hash
857  * buckets applicable to the inode numbers in audit_names.
858  * Regarding audit_state, same rules apply as for audit_filter_syscall().
859  */
audit_filter_inodes(struct task_struct * tsk,struct audit_context * ctx)860 void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
861 {
862 	struct audit_names *n;
863 
864 	if (auditd_test_task(tsk))
865 		return;
866 
867 	rcu_read_lock();
868 
869 	list_for_each_entry(n, &ctx->names_list, list) {
870 		if (audit_filter_inode_name(tsk, n, ctx))
871 			break;
872 	}
873 	rcu_read_unlock();
874 }
875 
audit_proctitle_free(struct audit_context * context)876 static inline void audit_proctitle_free(struct audit_context *context)
877 {
878 	kfree(context->proctitle.value);
879 	context->proctitle.value = NULL;
880 	context->proctitle.len = 0;
881 }
882 
audit_free_module(struct audit_context * context)883 static inline void audit_free_module(struct audit_context *context)
884 {
885 	if (context->type == AUDIT_KERN_MODULE) {
886 		kfree(context->module.name);
887 		context->module.name = NULL;
888 	}
889 }
audit_free_names(struct audit_context * context)890 static inline void audit_free_names(struct audit_context *context)
891 {
892 	struct audit_names *n, *next;
893 
894 	list_for_each_entry_safe(n, next, &context->names_list, list) {
895 		list_del(&n->list);
896 		if (n->name)
897 			putname(n->name);
898 		if (n->should_free)
899 			kfree(n);
900 	}
901 	context->name_count = 0;
902 	path_put(&context->pwd);
903 	context->pwd.dentry = NULL;
904 	context->pwd.mnt = NULL;
905 }
906 
audit_free_aux(struct audit_context * context)907 static inline void audit_free_aux(struct audit_context *context)
908 {
909 	struct audit_aux_data *aux;
910 
911 	while ((aux = context->aux)) {
912 		context->aux = aux->next;
913 		kfree(aux);
914 	}
915 	while ((aux = context->aux_pids)) {
916 		context->aux_pids = aux->next;
917 		kfree(aux);
918 	}
919 }
920 
audit_alloc_context(enum audit_state state)921 static inline struct audit_context *audit_alloc_context(enum audit_state state)
922 {
923 	struct audit_context *context;
924 
925 	context = kzalloc(sizeof(*context), GFP_KERNEL);
926 	if (!context)
927 		return NULL;
928 	context->state = state;
929 	context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
930 	INIT_LIST_HEAD(&context->killed_trees);
931 	INIT_LIST_HEAD(&context->names_list);
932 	return context;
933 }
934 
935 /**
936  * audit_alloc - allocate an audit context block for a task
937  * @tsk: task
938  *
939  * Filter on the task information and allocate a per-task audit context
940  * if necessary.  Doing so turns on system call auditing for the
941  * specified task.  This is called from copy_process, so no lock is
942  * needed.
943  */
audit_alloc(struct task_struct * tsk)944 int audit_alloc(struct task_struct *tsk)
945 {
946 	struct audit_context *context;
947 	enum audit_state     state;
948 	char *key = NULL;
949 
950 	if (likely(!audit_ever_enabled))
951 		return 0; /* Return if not auditing. */
952 
953 	state = audit_filter_task(tsk, &key);
954 	if (state == AUDIT_DISABLED) {
955 		clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
956 		return 0;
957 	}
958 
959 	if (!(context = audit_alloc_context(state))) {
960 		kfree(key);
961 		audit_log_lost("out of memory in audit_alloc");
962 		return -ENOMEM;
963 	}
964 	context->filterkey = key;
965 
966 	audit_set_context(tsk, context);
967 	set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
968 	return 0;
969 }
970 
audit_free_context(struct audit_context * context)971 static inline void audit_free_context(struct audit_context *context)
972 {
973 	audit_free_module(context);
974 	audit_free_names(context);
975 	unroll_tree_refs(context, NULL, 0);
976 	free_tree_refs(context);
977 	audit_free_aux(context);
978 	kfree(context->filterkey);
979 	kfree(context->sockaddr);
980 	audit_proctitle_free(context);
981 	kfree(context);
982 }
983 
audit_log_pid_context(struct audit_context * context,pid_t pid,kuid_t auid,kuid_t uid,unsigned int sessionid,u32 sid,char * comm)984 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
985 				 kuid_t auid, kuid_t uid, unsigned int sessionid,
986 				 u32 sid, char *comm)
987 {
988 	struct audit_buffer *ab;
989 	char *ctx = NULL;
990 	u32 len;
991 	int rc = 0;
992 
993 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
994 	if (!ab)
995 		return rc;
996 
997 	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
998 			 from_kuid(&init_user_ns, auid),
999 			 from_kuid(&init_user_ns, uid), sessionid);
1000 	if (sid) {
1001 		if (security_secid_to_secctx(sid, &ctx, &len)) {
1002 			audit_log_format(ab, " obj=(none)");
1003 			rc = 1;
1004 		} else {
1005 			audit_log_format(ab, " obj=%s", ctx);
1006 			security_release_secctx(ctx, len);
1007 		}
1008 	}
1009 	audit_log_format(ab, " ocomm=");
1010 	audit_log_untrustedstring(ab, comm);
1011 	audit_log_end(ab);
1012 
1013 	return rc;
1014 }
1015 
audit_log_execve_info(struct audit_context * context,struct audit_buffer ** ab)1016 static void audit_log_execve_info(struct audit_context *context,
1017 				  struct audit_buffer **ab)
1018 {
1019 	long len_max;
1020 	long len_rem;
1021 	long len_full;
1022 	long len_buf;
1023 	long len_abuf = 0;
1024 	long len_tmp;
1025 	bool require_data;
1026 	bool encode;
1027 	unsigned int iter;
1028 	unsigned int arg;
1029 	char *buf_head;
1030 	char *buf;
1031 	const char __user *p = (const char __user *)current->mm->arg_start;
1032 
1033 	/* NOTE: this buffer needs to be large enough to hold all the non-arg
1034 	 *       data we put in the audit record for this argument (see the
1035 	 *       code below) ... at this point in time 96 is plenty */
1036 	char abuf[96];
1037 
1038 	/* NOTE: we set MAX_EXECVE_AUDIT_LEN to a rather arbitrary limit, the
1039 	 *       current value of 7500 is not as important as the fact that it
1040 	 *       is less than 8k, a setting of 7500 gives us plenty of wiggle
1041 	 *       room if we go over a little bit in the logging below */
1042 	WARN_ON_ONCE(MAX_EXECVE_AUDIT_LEN > 7500);
1043 	len_max = MAX_EXECVE_AUDIT_LEN;
1044 
1045 	/* scratch buffer to hold the userspace args */
1046 	buf_head = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
1047 	if (!buf_head) {
1048 		audit_panic("out of memory for argv string");
1049 		return;
1050 	}
1051 	buf = buf_head;
1052 
1053 	audit_log_format(*ab, "argc=%d", context->execve.argc);
1054 
1055 	len_rem = len_max;
1056 	len_buf = 0;
1057 	len_full = 0;
1058 	require_data = true;
1059 	encode = false;
1060 	iter = 0;
1061 	arg = 0;
1062 	do {
1063 		/* NOTE: we don't ever want to trust this value for anything
1064 		 *       serious, but the audit record format insists we
1065 		 *       provide an argument length for really long arguments,
1066 		 *       e.g. > MAX_EXECVE_AUDIT_LEN, so we have no choice but
1067 		 *       to use strncpy_from_user() to obtain this value for
1068 		 *       recording in the log, although we don't use it
1069 		 *       anywhere here to avoid a double-fetch problem */
1070 		if (len_full == 0)
1071 			len_full = strnlen_user(p, MAX_ARG_STRLEN) - 1;
1072 
1073 		/* read more data from userspace */
1074 		if (require_data) {
1075 			/* can we make more room in the buffer? */
1076 			if (buf != buf_head) {
1077 				memmove(buf_head, buf, len_buf);
1078 				buf = buf_head;
1079 			}
1080 
1081 			/* fetch as much as we can of the argument */
1082 			len_tmp = strncpy_from_user(&buf_head[len_buf], p,
1083 						    len_max - len_buf);
1084 			if (len_tmp == -EFAULT) {
1085 				/* unable to copy from userspace */
1086 				send_sig(SIGKILL, current, 0);
1087 				goto out;
1088 			} else if (len_tmp == (len_max - len_buf)) {
1089 				/* buffer is not large enough */
1090 				require_data = true;
1091 				/* NOTE: if we are going to span multiple
1092 				 *       buffers force the encoding so we stand
1093 				 *       a chance at a sane len_full value and
1094 				 *       consistent record encoding */
1095 				encode = true;
1096 				len_full = len_full * 2;
1097 				p += len_tmp;
1098 			} else {
1099 				require_data = false;
1100 				if (!encode)
1101 					encode = audit_string_contains_control(
1102 								buf, len_tmp);
1103 				/* try to use a trusted value for len_full */
1104 				if (len_full < len_max)
1105 					len_full = (encode ?
1106 						    len_tmp * 2 : len_tmp);
1107 				p += len_tmp + 1;
1108 			}
1109 			len_buf += len_tmp;
1110 			buf_head[len_buf] = '\0';
1111 
1112 			/* length of the buffer in the audit record? */
1113 			len_abuf = (encode ? len_buf * 2 : len_buf + 2);
1114 		}
1115 
1116 		/* write as much as we can to the audit log */
1117 		if (len_buf >= 0) {
1118 			/* NOTE: some magic numbers here - basically if we
1119 			 *       can't fit a reasonable amount of data into the
1120 			 *       existing audit buffer, flush it and start with
1121 			 *       a new buffer */
1122 			if ((sizeof(abuf) + 8) > len_rem) {
1123 				len_rem = len_max;
1124 				audit_log_end(*ab);
1125 				*ab = audit_log_start(context,
1126 						      GFP_KERNEL, AUDIT_EXECVE);
1127 				if (!*ab)
1128 					goto out;
1129 			}
1130 
1131 			/* create the non-arg portion of the arg record */
1132 			len_tmp = 0;
1133 			if (require_data || (iter > 0) ||
1134 			    ((len_abuf + sizeof(abuf)) > len_rem)) {
1135 				if (iter == 0) {
1136 					len_tmp += snprintf(&abuf[len_tmp],
1137 							sizeof(abuf) - len_tmp,
1138 							" a%d_len=%lu",
1139 							arg, len_full);
1140 				}
1141 				len_tmp += snprintf(&abuf[len_tmp],
1142 						    sizeof(abuf) - len_tmp,
1143 						    " a%d[%d]=", arg, iter++);
1144 			} else
1145 				len_tmp += snprintf(&abuf[len_tmp],
1146 						    sizeof(abuf) - len_tmp,
1147 						    " a%d=", arg);
1148 			WARN_ON(len_tmp >= sizeof(abuf));
1149 			abuf[sizeof(abuf) - 1] = '\0';
1150 
1151 			/* log the arg in the audit record */
1152 			audit_log_format(*ab, "%s", abuf);
1153 			len_rem -= len_tmp;
1154 			len_tmp = len_buf;
1155 			if (encode) {
1156 				if (len_abuf > len_rem)
1157 					len_tmp = len_rem / 2; /* encoding */
1158 				audit_log_n_hex(*ab, buf, len_tmp);
1159 				len_rem -= len_tmp * 2;
1160 				len_abuf -= len_tmp * 2;
1161 			} else {
1162 				if (len_abuf > len_rem)
1163 					len_tmp = len_rem - 2; /* quotes */
1164 				audit_log_n_string(*ab, buf, len_tmp);
1165 				len_rem -= len_tmp + 2;
1166 				/* don't subtract the "2" because we still need
1167 				 * to add quotes to the remaining string */
1168 				len_abuf -= len_tmp;
1169 			}
1170 			len_buf -= len_tmp;
1171 			buf += len_tmp;
1172 		}
1173 
1174 		/* ready to move to the next argument? */
1175 		if ((len_buf == 0) && !require_data) {
1176 			arg++;
1177 			iter = 0;
1178 			len_full = 0;
1179 			require_data = true;
1180 			encode = false;
1181 		}
1182 	} while (arg < context->execve.argc);
1183 
1184 	/* NOTE: the caller handles the final audit_log_end() call */
1185 
1186 out:
1187 	kfree(buf_head);
1188 }
1189 
audit_log_cap(struct audit_buffer * ab,char * prefix,kernel_cap_t * cap)1190 static void audit_log_cap(struct audit_buffer *ab, char *prefix,
1191 			  kernel_cap_t *cap)
1192 {
1193 	int i;
1194 
1195 	if (cap_isclear(*cap)) {
1196 		audit_log_format(ab, " %s=0", prefix);
1197 		return;
1198 	}
1199 	audit_log_format(ab, " %s=", prefix);
1200 	CAP_FOR_EACH_U32(i)
1201 		audit_log_format(ab, "%08x", cap->cap[CAP_LAST_U32 - i]);
1202 }
1203 
audit_log_fcaps(struct audit_buffer * ab,struct audit_names * name)1204 static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
1205 {
1206 	if (name->fcap_ver == -1) {
1207 		audit_log_format(ab, " cap_fe=? cap_fver=? cap_fp=? cap_fi=?");
1208 		return;
1209 	}
1210 	audit_log_cap(ab, "cap_fp", &name->fcap.permitted);
1211 	audit_log_cap(ab, "cap_fi", &name->fcap.inheritable);
1212 	audit_log_format(ab, " cap_fe=%d cap_fver=%x cap_frootid=%d",
1213 			 name->fcap.fE, name->fcap_ver,
1214 			 from_kuid(&init_user_ns, name->fcap.rootid));
1215 }
1216 
audit_log_time(struct audit_context * context,struct audit_buffer ** ab)1217 static void audit_log_time(struct audit_context *context, struct audit_buffer **ab)
1218 {
1219 	const struct audit_ntp_data *ntp = &context->time.ntp_data;
1220 	const struct timespec64 *tk = &context->time.tk_injoffset;
1221 	static const char * const ntp_name[] = {
1222 		"offset",
1223 		"freq",
1224 		"status",
1225 		"tai",
1226 		"tick",
1227 		"adjust",
1228 	};
1229 	int type;
1230 
1231 	if (context->type == AUDIT_TIME_ADJNTPVAL) {
1232 		for (type = 0; type < AUDIT_NTP_NVALS; type++) {
1233 			if (ntp->vals[type].newval != ntp->vals[type].oldval) {
1234 				if (!*ab) {
1235 					*ab = audit_log_start(context,
1236 							GFP_KERNEL,
1237 							AUDIT_TIME_ADJNTPVAL);
1238 					if (!*ab)
1239 						return;
1240 				}
1241 				audit_log_format(*ab, "op=%s old=%lli new=%lli",
1242 						 ntp_name[type],
1243 						 ntp->vals[type].oldval,
1244 						 ntp->vals[type].newval);
1245 				audit_log_end(*ab);
1246 				*ab = NULL;
1247 			}
1248 		}
1249 	}
1250 	if (tk->tv_sec != 0 || tk->tv_nsec != 0) {
1251 		if (!*ab) {
1252 			*ab = audit_log_start(context, GFP_KERNEL,
1253 					      AUDIT_TIME_INJOFFSET);
1254 			if (!*ab)
1255 				return;
1256 		}
1257 		audit_log_format(*ab, "sec=%lli nsec=%li",
1258 				 (long long)tk->tv_sec, tk->tv_nsec);
1259 		audit_log_end(*ab);
1260 		*ab = NULL;
1261 	}
1262 }
1263 
show_special(struct audit_context * context,int * call_panic)1264 static void show_special(struct audit_context *context, int *call_panic)
1265 {
1266 	struct audit_buffer *ab;
1267 	int i;
1268 
1269 	ab = audit_log_start(context, GFP_KERNEL, context->type);
1270 	if (!ab)
1271 		return;
1272 
1273 	switch (context->type) {
1274 	case AUDIT_SOCKETCALL: {
1275 		int nargs = context->socketcall.nargs;
1276 		audit_log_format(ab, "nargs=%d", nargs);
1277 		for (i = 0; i < nargs; i++)
1278 			audit_log_format(ab, " a%d=%lx", i,
1279 				context->socketcall.args[i]);
1280 		break; }
1281 	case AUDIT_IPC: {
1282 		u32 osid = context->ipc.osid;
1283 
1284 		audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
1285 				 from_kuid(&init_user_ns, context->ipc.uid),
1286 				 from_kgid(&init_user_ns, context->ipc.gid),
1287 				 context->ipc.mode);
1288 		if (osid) {
1289 			char *ctx = NULL;
1290 			u32 len;
1291 			if (security_secid_to_secctx(osid, &ctx, &len)) {
1292 				audit_log_format(ab, " osid=%u", osid);
1293 				*call_panic = 1;
1294 			} else {
1295 				audit_log_format(ab, " obj=%s", ctx);
1296 				security_release_secctx(ctx, len);
1297 			}
1298 		}
1299 		if (context->ipc.has_perm) {
1300 			audit_log_end(ab);
1301 			ab = audit_log_start(context, GFP_KERNEL,
1302 					     AUDIT_IPC_SET_PERM);
1303 			if (unlikely(!ab))
1304 				return;
1305 			audit_log_format(ab,
1306 				"qbytes=%lx ouid=%u ogid=%u mode=%#ho",
1307 				context->ipc.qbytes,
1308 				context->ipc.perm_uid,
1309 				context->ipc.perm_gid,
1310 				context->ipc.perm_mode);
1311 		}
1312 		break; }
1313 	case AUDIT_MQ_OPEN:
1314 		audit_log_format(ab,
1315 			"oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "
1316 			"mq_msgsize=%ld mq_curmsgs=%ld",
1317 			context->mq_open.oflag, context->mq_open.mode,
1318 			context->mq_open.attr.mq_flags,
1319 			context->mq_open.attr.mq_maxmsg,
1320 			context->mq_open.attr.mq_msgsize,
1321 			context->mq_open.attr.mq_curmsgs);
1322 		break;
1323 	case AUDIT_MQ_SENDRECV:
1324 		audit_log_format(ab,
1325 			"mqdes=%d msg_len=%zd msg_prio=%u "
1326 			"abs_timeout_sec=%lld abs_timeout_nsec=%ld",
1327 			context->mq_sendrecv.mqdes,
1328 			context->mq_sendrecv.msg_len,
1329 			context->mq_sendrecv.msg_prio,
1330 			(long long) context->mq_sendrecv.abs_timeout.tv_sec,
1331 			context->mq_sendrecv.abs_timeout.tv_nsec);
1332 		break;
1333 	case AUDIT_MQ_NOTIFY:
1334 		audit_log_format(ab, "mqdes=%d sigev_signo=%d",
1335 				context->mq_notify.mqdes,
1336 				context->mq_notify.sigev_signo);
1337 		break;
1338 	case AUDIT_MQ_GETSETATTR: {
1339 		struct mq_attr *attr = &context->mq_getsetattr.mqstat;
1340 		audit_log_format(ab,
1341 			"mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
1342 			"mq_curmsgs=%ld ",
1343 			context->mq_getsetattr.mqdes,
1344 			attr->mq_flags, attr->mq_maxmsg,
1345 			attr->mq_msgsize, attr->mq_curmsgs);
1346 		break; }
1347 	case AUDIT_CAPSET:
1348 		audit_log_format(ab, "pid=%d", context->capset.pid);
1349 		audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
1350 		audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
1351 		audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
1352 		audit_log_cap(ab, "cap_pa", &context->capset.cap.ambient);
1353 		break;
1354 	case AUDIT_MMAP:
1355 		audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
1356 				 context->mmap.flags);
1357 		break;
1358 	case AUDIT_EXECVE:
1359 		audit_log_execve_info(context, &ab);
1360 		break;
1361 	case AUDIT_KERN_MODULE:
1362 		audit_log_format(ab, "name=");
1363 		if (context->module.name) {
1364 			audit_log_untrustedstring(ab, context->module.name);
1365 		} else
1366 			audit_log_format(ab, "(null)");
1367 
1368 		break;
1369 	case AUDIT_TIME_ADJNTPVAL:
1370 	case AUDIT_TIME_INJOFFSET:
1371 		/* this call deviates from the rest, eating the buffer */
1372 		audit_log_time(context, &ab);
1373 		break;
1374 	}
1375 	audit_log_end(ab);
1376 }
1377 
audit_proctitle_rtrim(char * proctitle,int len)1378 static inline int audit_proctitle_rtrim(char *proctitle, int len)
1379 {
1380 	char *end = proctitle + len - 1;
1381 	while (end > proctitle && !isprint(*end))
1382 		end--;
1383 
1384 	/* catch the case where proctitle is only 1 non-print character */
1385 	len = end - proctitle + 1;
1386 	len -= isprint(proctitle[len-1]) == 0;
1387 	return len;
1388 }
1389 
1390 /*
1391  * audit_log_name - produce AUDIT_PATH record from struct audit_names
1392  * @context: audit_context for the task
1393  * @n: audit_names structure with reportable details
1394  * @path: optional path to report instead of audit_names->name
1395  * @record_num: record number to report when handling a list of names
1396  * @call_panic: optional pointer to int that will be updated if secid fails
1397  */
audit_log_name(struct audit_context * context,struct audit_names * n,const struct path * path,int record_num,int * call_panic)1398 static void audit_log_name(struct audit_context *context, struct audit_names *n,
1399 		    const struct path *path, int record_num, int *call_panic)
1400 {
1401 	struct audit_buffer *ab;
1402 
1403 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
1404 	if (!ab)
1405 		return;
1406 
1407 	audit_log_format(ab, "item=%d", record_num);
1408 
1409 	if (path)
1410 		audit_log_d_path(ab, " name=", path);
1411 	else if (n->name) {
1412 		switch (n->name_len) {
1413 		case AUDIT_NAME_FULL:
1414 			/* log the full path */
1415 			audit_log_format(ab, " name=");
1416 			audit_log_untrustedstring(ab, n->name->name);
1417 			break;
1418 		case 0:
1419 			/* name was specified as a relative path and the
1420 			 * directory component is the cwd
1421 			 */
1422 			audit_log_d_path(ab, " name=", &context->pwd);
1423 			break;
1424 		default:
1425 			/* log the name's directory component */
1426 			audit_log_format(ab, " name=");
1427 			audit_log_n_untrustedstring(ab, n->name->name,
1428 						    n->name_len);
1429 		}
1430 	} else
1431 		audit_log_format(ab, " name=(null)");
1432 
1433 	if (n->ino != AUDIT_INO_UNSET)
1434 		audit_log_format(ab, " inode=%lu dev=%02x:%02x mode=%#ho ouid=%u ogid=%u rdev=%02x:%02x",
1435 				 n->ino,
1436 				 MAJOR(n->dev),
1437 				 MINOR(n->dev),
1438 				 n->mode,
1439 				 from_kuid(&init_user_ns, n->uid),
1440 				 from_kgid(&init_user_ns, n->gid),
1441 				 MAJOR(n->rdev),
1442 				 MINOR(n->rdev));
1443 	if (n->osid != 0) {
1444 		char *ctx = NULL;
1445 		u32 len;
1446 
1447 		if (security_secid_to_secctx(
1448 			n->osid, &ctx, &len)) {
1449 			audit_log_format(ab, " osid=%u", n->osid);
1450 			if (call_panic)
1451 				*call_panic = 2;
1452 		} else {
1453 			audit_log_format(ab, " obj=%s", ctx);
1454 			security_release_secctx(ctx, len);
1455 		}
1456 	}
1457 
1458 	/* log the audit_names record type */
1459 	switch (n->type) {
1460 	case AUDIT_TYPE_NORMAL:
1461 		audit_log_format(ab, " nametype=NORMAL");
1462 		break;
1463 	case AUDIT_TYPE_PARENT:
1464 		audit_log_format(ab, " nametype=PARENT");
1465 		break;
1466 	case AUDIT_TYPE_CHILD_DELETE:
1467 		audit_log_format(ab, " nametype=DELETE");
1468 		break;
1469 	case AUDIT_TYPE_CHILD_CREATE:
1470 		audit_log_format(ab, " nametype=CREATE");
1471 		break;
1472 	default:
1473 		audit_log_format(ab, " nametype=UNKNOWN");
1474 		break;
1475 	}
1476 
1477 	audit_log_fcaps(ab, n);
1478 	audit_log_end(ab);
1479 }
1480 
audit_log_proctitle(void)1481 static void audit_log_proctitle(void)
1482 {
1483 	int res;
1484 	char *buf;
1485 	char *msg = "(null)";
1486 	int len = strlen(msg);
1487 	struct audit_context *context = audit_context();
1488 	struct audit_buffer *ab;
1489 
1490 	if (!context || context->dummy)
1491 		return;
1492 
1493 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE);
1494 	if (!ab)
1495 		return;	/* audit_panic or being filtered */
1496 
1497 	audit_log_format(ab, "proctitle=");
1498 
1499 	/* Not  cached */
1500 	if (!context->proctitle.value) {
1501 		buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL);
1502 		if (!buf)
1503 			goto out;
1504 		/* Historically called this from procfs naming */
1505 		res = get_cmdline(current, buf, MAX_PROCTITLE_AUDIT_LEN);
1506 		if (res == 0) {
1507 			kfree(buf);
1508 			goto out;
1509 		}
1510 		res = audit_proctitle_rtrim(buf, res);
1511 		if (res == 0) {
1512 			kfree(buf);
1513 			goto out;
1514 		}
1515 		context->proctitle.value = buf;
1516 		context->proctitle.len = res;
1517 	}
1518 	msg = context->proctitle.value;
1519 	len = context->proctitle.len;
1520 out:
1521 	audit_log_n_untrustedstring(ab, msg, len);
1522 	audit_log_end(ab);
1523 }
1524 
audit_log_exit(void)1525 static void audit_log_exit(void)
1526 {
1527 	int i, call_panic = 0;
1528 	struct audit_context *context = audit_context();
1529 	struct audit_buffer *ab;
1530 	struct audit_aux_data *aux;
1531 	struct audit_names *n;
1532 
1533 	context->personality = current->personality;
1534 
1535 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
1536 	if (!ab)
1537 		return;		/* audit_panic has been called */
1538 	audit_log_format(ab, "arch=%x syscall=%d",
1539 			 context->arch, context->major);
1540 	if (context->personality != PER_LINUX)
1541 		audit_log_format(ab, " per=%lx", context->personality);
1542 	if (context->return_valid)
1543 		audit_log_format(ab, " success=%s exit=%ld",
1544 				 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
1545 				 context->return_code);
1546 
1547 	audit_log_format(ab,
1548 			 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d",
1549 			 context->argv[0],
1550 			 context->argv[1],
1551 			 context->argv[2],
1552 			 context->argv[3],
1553 			 context->name_count);
1554 
1555 	audit_log_task_info(ab);
1556 	audit_log_key(ab, context->filterkey);
1557 	audit_log_end(ab);
1558 
1559 	for (aux = context->aux; aux; aux = aux->next) {
1560 
1561 		ab = audit_log_start(context, GFP_KERNEL, aux->type);
1562 		if (!ab)
1563 			continue; /* audit_panic has been called */
1564 
1565 		switch (aux->type) {
1566 
1567 		case AUDIT_BPRM_FCAPS: {
1568 			struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
1569 			audit_log_format(ab, "fver=%x", axs->fcap_ver);
1570 			audit_log_cap(ab, "fp", &axs->fcap.permitted);
1571 			audit_log_cap(ab, "fi", &axs->fcap.inheritable);
1572 			audit_log_format(ab, " fe=%d", axs->fcap.fE);
1573 			audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
1574 			audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
1575 			audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
1576 			audit_log_cap(ab, "old_pa", &axs->old_pcap.ambient);
1577 			audit_log_cap(ab, "pp", &axs->new_pcap.permitted);
1578 			audit_log_cap(ab, "pi", &axs->new_pcap.inheritable);
1579 			audit_log_cap(ab, "pe", &axs->new_pcap.effective);
1580 			audit_log_cap(ab, "pa", &axs->new_pcap.ambient);
1581 			audit_log_format(ab, " frootid=%d",
1582 					 from_kuid(&init_user_ns,
1583 						   axs->fcap.rootid));
1584 			break; }
1585 
1586 		}
1587 		audit_log_end(ab);
1588 	}
1589 
1590 	if (context->type)
1591 		show_special(context, &call_panic);
1592 
1593 	if (context->fds[0] >= 0) {
1594 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
1595 		if (ab) {
1596 			audit_log_format(ab, "fd0=%d fd1=%d",
1597 					context->fds[0], context->fds[1]);
1598 			audit_log_end(ab);
1599 		}
1600 	}
1601 
1602 	if (context->sockaddr_len) {
1603 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
1604 		if (ab) {
1605 			audit_log_format(ab, "saddr=");
1606 			audit_log_n_hex(ab, (void *)context->sockaddr,
1607 					context->sockaddr_len);
1608 			audit_log_end(ab);
1609 		}
1610 	}
1611 
1612 	for (aux = context->aux_pids; aux; aux = aux->next) {
1613 		struct audit_aux_data_pids *axs = (void *)aux;
1614 
1615 		for (i = 0; i < axs->pid_count; i++)
1616 			if (audit_log_pid_context(context, axs->target_pid[i],
1617 						  axs->target_auid[i],
1618 						  axs->target_uid[i],
1619 						  axs->target_sessionid[i],
1620 						  axs->target_sid[i],
1621 						  axs->target_comm[i]))
1622 				call_panic = 1;
1623 	}
1624 
1625 	if (context->target_pid &&
1626 	    audit_log_pid_context(context, context->target_pid,
1627 				  context->target_auid, context->target_uid,
1628 				  context->target_sessionid,
1629 				  context->target_sid, context->target_comm))
1630 			call_panic = 1;
1631 
1632 	if (context->pwd.dentry && context->pwd.mnt) {
1633 		ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1634 		if (ab) {
1635 			audit_log_d_path(ab, "cwd=", &context->pwd);
1636 			audit_log_end(ab);
1637 		}
1638 	}
1639 
1640 	i = 0;
1641 	list_for_each_entry(n, &context->names_list, list) {
1642 		if (n->hidden)
1643 			continue;
1644 		audit_log_name(context, n, NULL, i++, &call_panic);
1645 	}
1646 
1647 	audit_log_proctitle();
1648 
1649 	/* Send end of event record to help user space know we are finished */
1650 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
1651 	if (ab)
1652 		audit_log_end(ab);
1653 	if (call_panic)
1654 		audit_panic("error converting sid to string");
1655 }
1656 
1657 /**
1658  * __audit_free - free a per-task audit context
1659  * @tsk: task whose audit context block to free
1660  *
1661  * Called from copy_process and do_exit
1662  */
__audit_free(struct task_struct * tsk)1663 void __audit_free(struct task_struct *tsk)
1664 {
1665 	struct audit_context *context = tsk->audit_context;
1666 
1667 	if (!context)
1668 		return;
1669 
1670 	if (!list_empty(&context->killed_trees))
1671 		audit_kill_trees(context);
1672 
1673 	/* We are called either by do_exit() or the fork() error handling code;
1674 	 * in the former case tsk == current and in the latter tsk is a
1675 	 * random task_struct that doesn't doesn't have any meaningful data we
1676 	 * need to log via audit_log_exit().
1677 	 */
1678 	if (tsk == current && !context->dummy && context->in_syscall) {
1679 		context->return_valid = 0;
1680 		context->return_code = 0;
1681 
1682 		audit_filter_syscall(tsk, context,
1683 				     &audit_filter_list[AUDIT_FILTER_EXIT]);
1684 		audit_filter_inodes(tsk, context);
1685 		if (context->current_state == AUDIT_RECORD_CONTEXT)
1686 			audit_log_exit();
1687 	}
1688 
1689 	audit_set_context(tsk, NULL);
1690 	audit_free_context(context);
1691 }
1692 
1693 /**
1694  * __audit_syscall_entry - fill in an audit record at syscall entry
1695  * @major: major syscall type (function)
1696  * @a1: additional syscall register 1
1697  * @a2: additional syscall register 2
1698  * @a3: additional syscall register 3
1699  * @a4: additional syscall register 4
1700  *
1701  * Fill in audit context at syscall entry.  This only happens if the
1702  * audit context was created when the task was created and the state or
1703  * filters demand the audit context be built.  If the state from the
1704  * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
1705  * then the record will be written at syscall exit time (otherwise, it
1706  * will only be written if another part of the kernel requests that it
1707  * be written).
1708  */
__audit_syscall_entry(int major,unsigned long a1,unsigned long a2,unsigned long a3,unsigned long a4)1709 void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2,
1710 			   unsigned long a3, unsigned long a4)
1711 {
1712 	struct audit_context *context = audit_context();
1713 	enum audit_state     state;
1714 
1715 	if (!audit_enabled || !context)
1716 		return;
1717 
1718 	BUG_ON(context->in_syscall || context->name_count);
1719 
1720 	state = context->state;
1721 	if (state == AUDIT_DISABLED)
1722 		return;
1723 
1724 	context->dummy = !audit_n_rules;
1725 	if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
1726 		context->prio = 0;
1727 		if (auditd_test_task(current))
1728 			return;
1729 	}
1730 
1731 	context->arch	    = syscall_get_arch(current);
1732 	context->major      = major;
1733 	context->argv[0]    = a1;
1734 	context->argv[1]    = a2;
1735 	context->argv[2]    = a3;
1736 	context->argv[3]    = a4;
1737 	context->serial     = 0;
1738 	context->in_syscall = 1;
1739 	context->current_state  = state;
1740 	context->ppid       = 0;
1741 	ktime_get_coarse_real_ts64(&context->ctime);
1742 }
1743 
1744 /**
1745  * __audit_syscall_exit - deallocate audit context after a system call
1746  * @success: success value of the syscall
1747  * @return_code: return value of the syscall
1748  *
1749  * Tear down after system call.  If the audit context has been marked as
1750  * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1751  * filtering, or because some other part of the kernel wrote an audit
1752  * message), then write out the syscall information.  In call cases,
1753  * free the names stored from getname().
1754  */
__audit_syscall_exit(int success,long return_code)1755 void __audit_syscall_exit(int success, long return_code)
1756 {
1757 	struct audit_context *context;
1758 
1759 	context = audit_context();
1760 	if (!context)
1761 		return;
1762 
1763 	if (!list_empty(&context->killed_trees))
1764 		audit_kill_trees(context);
1765 
1766 	if (!context->dummy && context->in_syscall) {
1767 		if (success)
1768 			context->return_valid = AUDITSC_SUCCESS;
1769 		else
1770 			context->return_valid = AUDITSC_FAILURE;
1771 
1772 		/*
1773 		 * we need to fix up the return code in the audit logs if the
1774 		 * actual return codes are later going to be fixed up by the
1775 		 * arch specific signal handlers
1776 		 *
1777 		 * This is actually a test for:
1778 		 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
1779 		 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
1780 		 *
1781 		 * but is faster than a bunch of ||
1782 		 */
1783 		if (unlikely(return_code <= -ERESTARTSYS) &&
1784 		    (return_code >= -ERESTART_RESTARTBLOCK) &&
1785 		    (return_code != -ENOIOCTLCMD))
1786 			context->return_code = -EINTR;
1787 		else
1788 			context->return_code  = return_code;
1789 
1790 		audit_filter_syscall(current, context,
1791 				     &audit_filter_list[AUDIT_FILTER_EXIT]);
1792 		audit_filter_inodes(current, context);
1793 		if (context->current_state == AUDIT_RECORD_CONTEXT)
1794 			audit_log_exit();
1795 	}
1796 
1797 	context->in_syscall = 0;
1798 	context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
1799 
1800 	audit_free_module(context);
1801 	audit_free_names(context);
1802 	unroll_tree_refs(context, NULL, 0);
1803 	audit_free_aux(context);
1804 	context->aux = NULL;
1805 	context->aux_pids = NULL;
1806 	context->target_pid = 0;
1807 	context->target_sid = 0;
1808 	context->sockaddr_len = 0;
1809 	context->type = 0;
1810 	context->fds[0] = -1;
1811 	if (context->state != AUDIT_RECORD_CONTEXT) {
1812 		kfree(context->filterkey);
1813 		context->filterkey = NULL;
1814 	}
1815 }
1816 
handle_one(const struct inode * inode)1817 static inline void handle_one(const struct inode *inode)
1818 {
1819 	struct audit_context *context;
1820 	struct audit_tree_refs *p;
1821 	struct audit_chunk *chunk;
1822 	int count;
1823 	if (likely(!inode->i_fsnotify_marks))
1824 		return;
1825 	context = audit_context();
1826 	p = context->trees;
1827 	count = context->tree_count;
1828 	rcu_read_lock();
1829 	chunk = audit_tree_lookup(inode);
1830 	rcu_read_unlock();
1831 	if (!chunk)
1832 		return;
1833 	if (likely(put_tree_ref(context, chunk)))
1834 		return;
1835 	if (unlikely(!grow_tree_refs(context))) {
1836 		pr_warn("out of memory, audit has lost a tree reference\n");
1837 		audit_set_auditable(context);
1838 		audit_put_chunk(chunk);
1839 		unroll_tree_refs(context, p, count);
1840 		return;
1841 	}
1842 	put_tree_ref(context, chunk);
1843 }
1844 
handle_path(const struct dentry * dentry)1845 static void handle_path(const struct dentry *dentry)
1846 {
1847 	struct audit_context *context;
1848 	struct audit_tree_refs *p;
1849 	const struct dentry *d, *parent;
1850 	struct audit_chunk *drop;
1851 	unsigned long seq;
1852 	int count;
1853 
1854 	context = audit_context();
1855 	p = context->trees;
1856 	count = context->tree_count;
1857 retry:
1858 	drop = NULL;
1859 	d = dentry;
1860 	rcu_read_lock();
1861 	seq = read_seqbegin(&rename_lock);
1862 	for(;;) {
1863 		struct inode *inode = d_backing_inode(d);
1864 		if (inode && unlikely(inode->i_fsnotify_marks)) {
1865 			struct audit_chunk *chunk;
1866 			chunk = audit_tree_lookup(inode);
1867 			if (chunk) {
1868 				if (unlikely(!put_tree_ref(context, chunk))) {
1869 					drop = chunk;
1870 					break;
1871 				}
1872 			}
1873 		}
1874 		parent = d->d_parent;
1875 		if (parent == d)
1876 			break;
1877 		d = parent;
1878 	}
1879 	if (unlikely(read_seqretry(&rename_lock, seq) || drop)) {  /* in this order */
1880 		rcu_read_unlock();
1881 		if (!drop) {
1882 			/* just a race with rename */
1883 			unroll_tree_refs(context, p, count);
1884 			goto retry;
1885 		}
1886 		audit_put_chunk(drop);
1887 		if (grow_tree_refs(context)) {
1888 			/* OK, got more space */
1889 			unroll_tree_refs(context, p, count);
1890 			goto retry;
1891 		}
1892 		/* too bad */
1893 		pr_warn("out of memory, audit has lost a tree reference\n");
1894 		unroll_tree_refs(context, p, count);
1895 		audit_set_auditable(context);
1896 		return;
1897 	}
1898 	rcu_read_unlock();
1899 }
1900 
audit_alloc_name(struct audit_context * context,unsigned char type)1901 static struct audit_names *audit_alloc_name(struct audit_context *context,
1902 						unsigned char type)
1903 {
1904 	struct audit_names *aname;
1905 
1906 	if (context->name_count < AUDIT_NAMES) {
1907 		aname = &context->preallocated_names[context->name_count];
1908 		memset(aname, 0, sizeof(*aname));
1909 	} else {
1910 		aname = kzalloc(sizeof(*aname), GFP_NOFS);
1911 		if (!aname)
1912 			return NULL;
1913 		aname->should_free = true;
1914 	}
1915 
1916 	aname->ino = AUDIT_INO_UNSET;
1917 	aname->type = type;
1918 	list_add_tail(&aname->list, &context->names_list);
1919 
1920 	context->name_count++;
1921 	return aname;
1922 }
1923 
1924 /**
1925  * __audit_reusename - fill out filename with info from existing entry
1926  * @uptr: userland ptr to pathname
1927  *
1928  * Search the audit_names list for the current audit context. If there is an
1929  * existing entry with a matching "uptr" then return the filename
1930  * associated with that audit_name. If not, return NULL.
1931  */
1932 struct filename *
__audit_reusename(const __user char * uptr)1933 __audit_reusename(const __user char *uptr)
1934 {
1935 	struct audit_context *context = audit_context();
1936 	struct audit_names *n;
1937 
1938 	list_for_each_entry(n, &context->names_list, list) {
1939 		if (!n->name)
1940 			continue;
1941 		if (n->name->uptr == uptr) {
1942 			n->name->refcnt++;
1943 			return n->name;
1944 		}
1945 	}
1946 	return NULL;
1947 }
1948 
_audit_getcwd(struct audit_context * context)1949 inline void _audit_getcwd(struct audit_context *context)
1950 {
1951 	if (!context->pwd.dentry)
1952 		get_fs_pwd(current->fs, &context->pwd);
1953 }
1954 
__audit_getcwd(void)1955 void __audit_getcwd(void)
1956 {
1957 	struct audit_context *context = audit_context();
1958 
1959 	if (context->in_syscall)
1960 		_audit_getcwd(context);
1961 }
1962 
1963 /**
1964  * __audit_getname - add a name to the list
1965  * @name: name to add
1966  *
1967  * Add a name to the list of audit names for this context.
1968  * Called from fs/namei.c:getname().
1969  */
__audit_getname(struct filename * name)1970 void __audit_getname(struct filename *name)
1971 {
1972 	struct audit_context *context = audit_context();
1973 	struct audit_names *n;
1974 
1975 	if (!context->in_syscall)
1976 		return;
1977 
1978 	n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
1979 	if (!n)
1980 		return;
1981 
1982 	n->name = name;
1983 	n->name_len = AUDIT_NAME_FULL;
1984 	name->aname = n;
1985 	name->refcnt++;
1986 
1987 	_audit_getcwd(context);
1988 }
1989 
audit_copy_fcaps(struct audit_names * name,const struct dentry * dentry)1990 static inline int audit_copy_fcaps(struct audit_names *name,
1991 				   const struct dentry *dentry)
1992 {
1993 	struct cpu_vfs_cap_data caps;
1994 	int rc;
1995 
1996 	if (!dentry)
1997 		return 0;
1998 
1999 	rc = get_vfs_caps_from_disk(dentry, &caps);
2000 	if (rc)
2001 		return rc;
2002 
2003 	name->fcap.permitted = caps.permitted;
2004 	name->fcap.inheritable = caps.inheritable;
2005 	name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2006 	name->fcap.rootid = caps.rootid;
2007 	name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >>
2008 				VFS_CAP_REVISION_SHIFT;
2009 
2010 	return 0;
2011 }
2012 
2013 /* Copy inode data into an audit_names. */
audit_copy_inode(struct audit_names * name,const struct dentry * dentry,struct inode * inode,unsigned int flags)2014 static void audit_copy_inode(struct audit_names *name,
2015 			     const struct dentry *dentry,
2016 			     struct inode *inode, unsigned int flags)
2017 {
2018 	name->ino   = inode->i_ino;
2019 	name->dev   = inode->i_sb->s_dev;
2020 	name->mode  = inode->i_mode;
2021 	name->uid   = inode->i_uid;
2022 	name->gid   = inode->i_gid;
2023 	name->rdev  = inode->i_rdev;
2024 	security_inode_getsecid(inode, &name->osid);
2025 	if (flags & AUDIT_INODE_NOEVAL) {
2026 		name->fcap_ver = -1;
2027 		return;
2028 	}
2029 	audit_copy_fcaps(name, dentry);
2030 }
2031 
2032 /**
2033  * __audit_inode - store the inode and device from a lookup
2034  * @name: name being audited
2035  * @dentry: dentry being audited
2036  * @flags: attributes for this particular entry
2037  */
__audit_inode(struct filename * name,const struct dentry * dentry,unsigned int flags)2038 void __audit_inode(struct filename *name, const struct dentry *dentry,
2039 		   unsigned int flags)
2040 {
2041 	struct audit_context *context = audit_context();
2042 	struct inode *inode = d_backing_inode(dentry);
2043 	struct audit_names *n;
2044 	bool parent = flags & AUDIT_INODE_PARENT;
2045 	struct audit_entry *e;
2046 	struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS];
2047 	int i;
2048 
2049 	if (!context->in_syscall)
2050 		return;
2051 
2052 	rcu_read_lock();
2053 	list_for_each_entry_rcu(e, list, list) {
2054 		for (i = 0; i < e->rule.field_count; i++) {
2055 			struct audit_field *f = &e->rule.fields[i];
2056 
2057 			if (f->type == AUDIT_FSTYPE
2058 			    && audit_comparator(inode->i_sb->s_magic,
2059 						f->op, f->val)
2060 			    && e->rule.action == AUDIT_NEVER) {
2061 				rcu_read_unlock();
2062 				return;
2063 			}
2064 		}
2065 	}
2066 	rcu_read_unlock();
2067 
2068 	if (!name)
2069 		goto out_alloc;
2070 
2071 	/*
2072 	 * If we have a pointer to an audit_names entry already, then we can
2073 	 * just use it directly if the type is correct.
2074 	 */
2075 	n = name->aname;
2076 	if (n) {
2077 		if (parent) {
2078 			if (n->type == AUDIT_TYPE_PARENT ||
2079 			    n->type == AUDIT_TYPE_UNKNOWN)
2080 				goto out;
2081 		} else {
2082 			if (n->type != AUDIT_TYPE_PARENT)
2083 				goto out;
2084 		}
2085 	}
2086 
2087 	list_for_each_entry_reverse(n, &context->names_list, list) {
2088 		if (n->ino) {
2089 			/* valid inode number, use that for the comparison */
2090 			if (n->ino != inode->i_ino ||
2091 			    n->dev != inode->i_sb->s_dev)
2092 				continue;
2093 		} else if (n->name) {
2094 			/* inode number has not been set, check the name */
2095 			if (strcmp(n->name->name, name->name))
2096 				continue;
2097 		} else
2098 			/* no inode and no name (?!) ... this is odd ... */
2099 			continue;
2100 
2101 		/* match the correct record type */
2102 		if (parent) {
2103 			if (n->type == AUDIT_TYPE_PARENT ||
2104 			    n->type == AUDIT_TYPE_UNKNOWN)
2105 				goto out;
2106 		} else {
2107 			if (n->type != AUDIT_TYPE_PARENT)
2108 				goto out;
2109 		}
2110 	}
2111 
2112 out_alloc:
2113 	/* unable to find an entry with both a matching name and type */
2114 	n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
2115 	if (!n)
2116 		return;
2117 	if (name) {
2118 		n->name = name;
2119 		name->refcnt++;
2120 	}
2121 
2122 out:
2123 	if (parent) {
2124 		n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL;
2125 		n->type = AUDIT_TYPE_PARENT;
2126 		if (flags & AUDIT_INODE_HIDDEN)
2127 			n->hidden = true;
2128 	} else {
2129 		n->name_len = AUDIT_NAME_FULL;
2130 		n->type = AUDIT_TYPE_NORMAL;
2131 	}
2132 	handle_path(dentry);
2133 	audit_copy_inode(n, dentry, inode, flags & AUDIT_INODE_NOEVAL);
2134 }
2135 
__audit_file(const struct file * file)2136 void __audit_file(const struct file *file)
2137 {
2138 	__audit_inode(NULL, file->f_path.dentry, 0);
2139 }
2140 
2141 /**
2142  * __audit_inode_child - collect inode info for created/removed objects
2143  * @parent: inode of dentry parent
2144  * @dentry: dentry being audited
2145  * @type:   AUDIT_TYPE_* value that we're looking for
2146  *
2147  * For syscalls that create or remove filesystem objects, audit_inode
2148  * can only collect information for the filesystem object's parent.
2149  * This call updates the audit context with the child's information.
2150  * Syscalls that create a new filesystem object must be hooked after
2151  * the object is created.  Syscalls that remove a filesystem object
2152  * must be hooked prior, in order to capture the target inode during
2153  * unsuccessful attempts.
2154  */
__audit_inode_child(struct inode * parent,const struct dentry * dentry,const unsigned char type)2155 void __audit_inode_child(struct inode *parent,
2156 			 const struct dentry *dentry,
2157 			 const unsigned char type)
2158 {
2159 	struct audit_context *context = audit_context();
2160 	struct inode *inode = d_backing_inode(dentry);
2161 	const struct qstr *dname = &dentry->d_name;
2162 	struct audit_names *n, *found_parent = NULL, *found_child = NULL;
2163 	struct audit_entry *e;
2164 	struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS];
2165 	int i;
2166 
2167 	if (!context->in_syscall)
2168 		return;
2169 
2170 	rcu_read_lock();
2171 	list_for_each_entry_rcu(e, list, list) {
2172 		for (i = 0; i < e->rule.field_count; i++) {
2173 			struct audit_field *f = &e->rule.fields[i];
2174 
2175 			if (f->type == AUDIT_FSTYPE
2176 			    && audit_comparator(parent->i_sb->s_magic,
2177 						f->op, f->val)
2178 			    && e->rule.action == AUDIT_NEVER) {
2179 				rcu_read_unlock();
2180 				return;
2181 			}
2182 		}
2183 	}
2184 	rcu_read_unlock();
2185 
2186 	if (inode)
2187 		handle_one(inode);
2188 
2189 	/* look for a parent entry first */
2190 	list_for_each_entry(n, &context->names_list, list) {
2191 		if (!n->name ||
2192 		    (n->type != AUDIT_TYPE_PARENT &&
2193 		     n->type != AUDIT_TYPE_UNKNOWN))
2194 			continue;
2195 
2196 		if (n->ino == parent->i_ino && n->dev == parent->i_sb->s_dev &&
2197 		    !audit_compare_dname_path(dname,
2198 					      n->name->name, n->name_len)) {
2199 			if (n->type == AUDIT_TYPE_UNKNOWN)
2200 				n->type = AUDIT_TYPE_PARENT;
2201 			found_parent = n;
2202 			break;
2203 		}
2204 	}
2205 
2206 	cond_resched();
2207 
2208 	/* is there a matching child entry? */
2209 	list_for_each_entry(n, &context->names_list, list) {
2210 		/* can only match entries that have a name */
2211 		if (!n->name ||
2212 		    (n->type != type && n->type != AUDIT_TYPE_UNKNOWN))
2213 			continue;
2214 
2215 		if (!strcmp(dname->name, n->name->name) ||
2216 		    !audit_compare_dname_path(dname, n->name->name,
2217 						found_parent ?
2218 						found_parent->name_len :
2219 						AUDIT_NAME_FULL)) {
2220 			if (n->type == AUDIT_TYPE_UNKNOWN)
2221 				n->type = type;
2222 			found_child = n;
2223 			break;
2224 		}
2225 	}
2226 
2227 	if (!found_parent) {
2228 		/* create a new, "anonymous" parent record */
2229 		n = audit_alloc_name(context, AUDIT_TYPE_PARENT);
2230 		if (!n)
2231 			return;
2232 		audit_copy_inode(n, NULL, parent, 0);
2233 	}
2234 
2235 	if (!found_child) {
2236 		found_child = audit_alloc_name(context, type);
2237 		if (!found_child)
2238 			return;
2239 
2240 		/* Re-use the name belonging to the slot for a matching parent
2241 		 * directory. All names for this context are relinquished in
2242 		 * audit_free_names() */
2243 		if (found_parent) {
2244 			found_child->name = found_parent->name;
2245 			found_child->name_len = AUDIT_NAME_FULL;
2246 			found_child->name->refcnt++;
2247 		}
2248 	}
2249 
2250 	if (inode)
2251 		audit_copy_inode(found_child, dentry, inode, 0);
2252 	else
2253 		found_child->ino = AUDIT_INO_UNSET;
2254 }
2255 EXPORT_SYMBOL_GPL(__audit_inode_child);
2256 
2257 /**
2258  * auditsc_get_stamp - get local copies of audit_context values
2259  * @ctx: audit_context for the task
2260  * @t: timespec64 to store time recorded in the audit_context
2261  * @serial: serial value that is recorded in the audit_context
2262  *
2263  * Also sets the context as auditable.
2264  */
auditsc_get_stamp(struct audit_context * ctx,struct timespec64 * t,unsigned int * serial)2265 int auditsc_get_stamp(struct audit_context *ctx,
2266 		       struct timespec64 *t, unsigned int *serial)
2267 {
2268 	if (!ctx->in_syscall)
2269 		return 0;
2270 	if (!ctx->serial)
2271 		ctx->serial = audit_serial();
2272 	t->tv_sec  = ctx->ctime.tv_sec;
2273 	t->tv_nsec = ctx->ctime.tv_nsec;
2274 	*serial    = ctx->serial;
2275 	if (!ctx->prio) {
2276 		ctx->prio = 1;
2277 		ctx->current_state = AUDIT_RECORD_CONTEXT;
2278 	}
2279 	return 1;
2280 }
2281 
2282 /**
2283  * __audit_mq_open - record audit data for a POSIX MQ open
2284  * @oflag: open flag
2285  * @mode: mode bits
2286  * @attr: queue attributes
2287  *
2288  */
__audit_mq_open(int oflag,umode_t mode,struct mq_attr * attr)2289 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
2290 {
2291 	struct audit_context *context = audit_context();
2292 
2293 	if (attr)
2294 		memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
2295 	else
2296 		memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2297 
2298 	context->mq_open.oflag = oflag;
2299 	context->mq_open.mode = mode;
2300 
2301 	context->type = AUDIT_MQ_OPEN;
2302 }
2303 
2304 /**
2305  * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2306  * @mqdes: MQ descriptor
2307  * @msg_len: Message length
2308  * @msg_prio: Message priority
2309  * @abs_timeout: Message timeout in absolute time
2310  *
2311  */
__audit_mq_sendrecv(mqd_t mqdes,size_t msg_len,unsigned int msg_prio,const struct timespec64 * abs_timeout)2312 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
2313 			const struct timespec64 *abs_timeout)
2314 {
2315 	struct audit_context *context = audit_context();
2316 	struct timespec64 *p = &context->mq_sendrecv.abs_timeout;
2317 
2318 	if (abs_timeout)
2319 		memcpy(p, abs_timeout, sizeof(*p));
2320 	else
2321 		memset(p, 0, sizeof(*p));
2322 
2323 	context->mq_sendrecv.mqdes = mqdes;
2324 	context->mq_sendrecv.msg_len = msg_len;
2325 	context->mq_sendrecv.msg_prio = msg_prio;
2326 
2327 	context->type = AUDIT_MQ_SENDRECV;
2328 }
2329 
2330 /**
2331  * __audit_mq_notify - record audit data for a POSIX MQ notify
2332  * @mqdes: MQ descriptor
2333  * @notification: Notification event
2334  *
2335  */
2336 
__audit_mq_notify(mqd_t mqdes,const struct sigevent * notification)2337 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2338 {
2339 	struct audit_context *context = audit_context();
2340 
2341 	if (notification)
2342 		context->mq_notify.sigev_signo = notification->sigev_signo;
2343 	else
2344 		context->mq_notify.sigev_signo = 0;
2345 
2346 	context->mq_notify.mqdes = mqdes;
2347 	context->type = AUDIT_MQ_NOTIFY;
2348 }
2349 
2350 /**
2351  * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
2352  * @mqdes: MQ descriptor
2353  * @mqstat: MQ flags
2354  *
2355  */
__audit_mq_getsetattr(mqd_t mqdes,struct mq_attr * mqstat)2356 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2357 {
2358 	struct audit_context *context = audit_context();
2359 	context->mq_getsetattr.mqdes = mqdes;
2360 	context->mq_getsetattr.mqstat = *mqstat;
2361 	context->type = AUDIT_MQ_GETSETATTR;
2362 }
2363 
2364 /**
2365  * __audit_ipc_obj - record audit data for ipc object
2366  * @ipcp: ipc permissions
2367  *
2368  */
__audit_ipc_obj(struct kern_ipc_perm * ipcp)2369 void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
2370 {
2371 	struct audit_context *context = audit_context();
2372 	context->ipc.uid = ipcp->uid;
2373 	context->ipc.gid = ipcp->gid;
2374 	context->ipc.mode = ipcp->mode;
2375 	context->ipc.has_perm = 0;
2376 	security_ipc_getsecid(ipcp, &context->ipc.osid);
2377 	context->type = AUDIT_IPC;
2378 }
2379 
2380 /**
2381  * __audit_ipc_set_perm - record audit data for new ipc permissions
2382  * @qbytes: msgq bytes
2383  * @uid: msgq user id
2384  * @gid: msgq group id
2385  * @mode: msgq mode (permissions)
2386  *
2387  * Called only after audit_ipc_obj().
2388  */
__audit_ipc_set_perm(unsigned long qbytes,uid_t uid,gid_t gid,umode_t mode)2389 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
2390 {
2391 	struct audit_context *context = audit_context();
2392 
2393 	context->ipc.qbytes = qbytes;
2394 	context->ipc.perm_uid = uid;
2395 	context->ipc.perm_gid = gid;
2396 	context->ipc.perm_mode = mode;
2397 	context->ipc.has_perm = 1;
2398 }
2399 
__audit_bprm(struct linux_binprm * bprm)2400 void __audit_bprm(struct linux_binprm *bprm)
2401 {
2402 	struct audit_context *context = audit_context();
2403 
2404 	context->type = AUDIT_EXECVE;
2405 	context->execve.argc = bprm->argc;
2406 }
2407 
2408 
2409 /**
2410  * __audit_socketcall - record audit data for sys_socketcall
2411  * @nargs: number of args, which should not be more than AUDITSC_ARGS.
2412  * @args: args array
2413  *
2414  */
__audit_socketcall(int nargs,unsigned long * args)2415 int __audit_socketcall(int nargs, unsigned long *args)
2416 {
2417 	struct audit_context *context = audit_context();
2418 
2419 	if (nargs <= 0 || nargs > AUDITSC_ARGS || !args)
2420 		return -EINVAL;
2421 	context->type = AUDIT_SOCKETCALL;
2422 	context->socketcall.nargs = nargs;
2423 	memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
2424 	return 0;
2425 }
2426 
2427 /**
2428  * __audit_fd_pair - record audit data for pipe and socketpair
2429  * @fd1: the first file descriptor
2430  * @fd2: the second file descriptor
2431  *
2432  */
__audit_fd_pair(int fd1,int fd2)2433 void __audit_fd_pair(int fd1, int fd2)
2434 {
2435 	struct audit_context *context = audit_context();
2436 	context->fds[0] = fd1;
2437 	context->fds[1] = fd2;
2438 }
2439 
2440 /**
2441  * __audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
2442  * @len: data length in user space
2443  * @a: data address in kernel space
2444  *
2445  * Returns 0 for success or NULL context or < 0 on error.
2446  */
__audit_sockaddr(int len,void * a)2447 int __audit_sockaddr(int len, void *a)
2448 {
2449 	struct audit_context *context = audit_context();
2450 
2451 	if (!context->sockaddr) {
2452 		void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
2453 		if (!p)
2454 			return -ENOMEM;
2455 		context->sockaddr = p;
2456 	}
2457 
2458 	context->sockaddr_len = len;
2459 	memcpy(context->sockaddr, a, len);
2460 	return 0;
2461 }
2462 
__audit_ptrace(struct task_struct * t)2463 void __audit_ptrace(struct task_struct *t)
2464 {
2465 	struct audit_context *context = audit_context();
2466 
2467 	context->target_pid = task_tgid_nr(t);
2468 	context->target_auid = audit_get_loginuid(t);
2469 	context->target_uid = task_uid(t);
2470 	context->target_sessionid = audit_get_sessionid(t);
2471 	security_task_getsecid(t, &context->target_sid);
2472 	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
2473 }
2474 
2475 /**
2476  * audit_signal_info_syscall - record signal info for syscalls
2477  * @t: task being signaled
2478  *
2479  * If the audit subsystem is being terminated, record the task (pid)
2480  * and uid that is doing that.
2481  */
audit_signal_info_syscall(struct task_struct * t)2482 int audit_signal_info_syscall(struct task_struct *t)
2483 {
2484 	struct audit_aux_data_pids *axp;
2485 	struct audit_context *ctx = audit_context();
2486 	kuid_t t_uid = task_uid(t);
2487 
2488 	if (!audit_signals || audit_dummy_context())
2489 		return 0;
2490 
2491 	/* optimize the common case by putting first signal recipient directly
2492 	 * in audit_context */
2493 	if (!ctx->target_pid) {
2494 		ctx->target_pid = task_tgid_nr(t);
2495 		ctx->target_auid = audit_get_loginuid(t);
2496 		ctx->target_uid = t_uid;
2497 		ctx->target_sessionid = audit_get_sessionid(t);
2498 		security_task_getsecid(t, &ctx->target_sid);
2499 		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
2500 		return 0;
2501 	}
2502 
2503 	axp = (void *)ctx->aux_pids;
2504 	if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
2505 		axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
2506 		if (!axp)
2507 			return -ENOMEM;
2508 
2509 		axp->d.type = AUDIT_OBJ_PID;
2510 		axp->d.next = ctx->aux_pids;
2511 		ctx->aux_pids = (void *)axp;
2512 	}
2513 	BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
2514 
2515 	axp->target_pid[axp->pid_count] = task_tgid_nr(t);
2516 	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2517 	axp->target_uid[axp->pid_count] = t_uid;
2518 	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2519 	security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2520 	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
2521 	axp->pid_count++;
2522 
2523 	return 0;
2524 }
2525 
2526 /**
2527  * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
2528  * @bprm: pointer to the bprm being processed
2529  * @new: the proposed new credentials
2530  * @old: the old credentials
2531  *
2532  * Simply check if the proc already has the caps given by the file and if not
2533  * store the priv escalation info for later auditing at the end of the syscall
2534  *
2535  * -Eric
2536  */
__audit_log_bprm_fcaps(struct linux_binprm * bprm,const struct cred * new,const struct cred * old)2537 int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
2538 			   const struct cred *new, const struct cred *old)
2539 {
2540 	struct audit_aux_data_bprm_fcaps *ax;
2541 	struct audit_context *context = audit_context();
2542 	struct cpu_vfs_cap_data vcaps;
2543 
2544 	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
2545 	if (!ax)
2546 		return -ENOMEM;
2547 
2548 	ax->d.type = AUDIT_BPRM_FCAPS;
2549 	ax->d.next = context->aux;
2550 	context->aux = (void *)ax;
2551 
2552 	get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps);
2553 
2554 	ax->fcap.permitted = vcaps.permitted;
2555 	ax->fcap.inheritable = vcaps.inheritable;
2556 	ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
2557 	ax->fcap.rootid = vcaps.rootid;
2558 	ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
2559 
2560 	ax->old_pcap.permitted   = old->cap_permitted;
2561 	ax->old_pcap.inheritable = old->cap_inheritable;
2562 	ax->old_pcap.effective   = old->cap_effective;
2563 	ax->old_pcap.ambient     = old->cap_ambient;
2564 
2565 	ax->new_pcap.permitted   = new->cap_permitted;
2566 	ax->new_pcap.inheritable = new->cap_inheritable;
2567 	ax->new_pcap.effective   = new->cap_effective;
2568 	ax->new_pcap.ambient     = new->cap_ambient;
2569 	return 0;
2570 }
2571 
2572 /**
2573  * __audit_log_capset - store information about the arguments to the capset syscall
2574  * @new: the new credentials
2575  * @old: the old (current) credentials
2576  *
2577  * Record the arguments userspace sent to sys_capset for later printing by the
2578  * audit system if applicable
2579  */
__audit_log_capset(const struct cred * new,const struct cred * old)2580 void __audit_log_capset(const struct cred *new, const struct cred *old)
2581 {
2582 	struct audit_context *context = audit_context();
2583 	context->capset.pid = task_tgid_nr(current);
2584 	context->capset.cap.effective   = new->cap_effective;
2585 	context->capset.cap.inheritable = new->cap_effective;
2586 	context->capset.cap.permitted   = new->cap_permitted;
2587 	context->capset.cap.ambient     = new->cap_ambient;
2588 	context->type = AUDIT_CAPSET;
2589 }
2590 
__audit_mmap_fd(int fd,int flags)2591 void __audit_mmap_fd(int fd, int flags)
2592 {
2593 	struct audit_context *context = audit_context();
2594 	context->mmap.fd = fd;
2595 	context->mmap.flags = flags;
2596 	context->type = AUDIT_MMAP;
2597 }
2598 
__audit_log_kern_module(char * name)2599 void __audit_log_kern_module(char *name)
2600 {
2601 	struct audit_context *context = audit_context();
2602 
2603 	context->module.name = kstrdup(name, GFP_KERNEL);
2604 	if (!context->module.name)
2605 		audit_log_lost("out of memory in __audit_log_kern_module");
2606 	context->type = AUDIT_KERN_MODULE;
2607 }
2608 
__audit_fanotify(unsigned int response)2609 void __audit_fanotify(unsigned int response)
2610 {
2611 	audit_log(audit_context(), GFP_KERNEL,
2612 		AUDIT_FANOTIFY,	"resp=%u", response);
2613 }
2614 
__audit_tk_injoffset(struct timespec64 offset)2615 void __audit_tk_injoffset(struct timespec64 offset)
2616 {
2617 	struct audit_context *context = audit_context();
2618 
2619 	/* only set type if not already set by NTP */
2620 	if (!context->type)
2621 		context->type = AUDIT_TIME_INJOFFSET;
2622 	memcpy(&context->time.tk_injoffset, &offset, sizeof(offset));
2623 }
2624 
__audit_ntp_log(const struct audit_ntp_data * ad)2625 void __audit_ntp_log(const struct audit_ntp_data *ad)
2626 {
2627 	struct audit_context *context = audit_context();
2628 	int type;
2629 
2630 	for (type = 0; type < AUDIT_NTP_NVALS; type++)
2631 		if (ad->vals[type].newval != ad->vals[type].oldval) {
2632 			/* unconditionally set type, overwriting TK */
2633 			context->type = AUDIT_TIME_ADJNTPVAL;
2634 			memcpy(&context->time.ntp_data, ad, sizeof(*ad));
2635 			break;
2636 		}
2637 }
2638 
__audit_log_nfcfg(const char * name,u8 af,unsigned int nentries,enum audit_nfcfgop op,gfp_t gfp)2639 void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries,
2640 		       enum audit_nfcfgop op, gfp_t gfp)
2641 {
2642 	struct audit_buffer *ab;
2643 	char comm[sizeof(current->comm)];
2644 
2645 	ab = audit_log_start(audit_context(), gfp, AUDIT_NETFILTER_CFG);
2646 	if (!ab)
2647 		return;
2648 	audit_log_format(ab, "table=%s family=%u entries=%u op=%s",
2649 			 name, af, nentries, audit_nfcfgs[op].s);
2650 
2651 	audit_log_format(ab, " pid=%u", task_pid_nr(current));
2652 	audit_log_task_context(ab); /* subj= */
2653 	audit_log_format(ab, " comm=");
2654 	audit_log_untrustedstring(ab, get_task_comm(comm, current));
2655 	audit_log_end(ab);
2656 }
2657 EXPORT_SYMBOL_GPL(__audit_log_nfcfg);
2658 
audit_log_task(struct audit_buffer * ab)2659 static void audit_log_task(struct audit_buffer *ab)
2660 {
2661 	kuid_t auid, uid;
2662 	kgid_t gid;
2663 	unsigned int sessionid;
2664 	char comm[sizeof(current->comm)];
2665 
2666 	auid = audit_get_loginuid(current);
2667 	sessionid = audit_get_sessionid(current);
2668 	current_uid_gid(&uid, &gid);
2669 
2670 	audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
2671 			 from_kuid(&init_user_ns, auid),
2672 			 from_kuid(&init_user_ns, uid),
2673 			 from_kgid(&init_user_ns, gid),
2674 			 sessionid);
2675 	audit_log_task_context(ab);
2676 	audit_log_format(ab, " pid=%d comm=", task_tgid_nr(current));
2677 	audit_log_untrustedstring(ab, get_task_comm(comm, current));
2678 	audit_log_d_path_exe(ab, current->mm);
2679 }
2680 
2681 /**
2682  * audit_core_dumps - record information about processes that end abnormally
2683  * @signr: signal value
2684  *
2685  * If a process ends with a core dump, something fishy is going on and we
2686  * should record the event for investigation.
2687  */
audit_core_dumps(long signr)2688 void audit_core_dumps(long signr)
2689 {
2690 	struct audit_buffer *ab;
2691 
2692 	if (!audit_enabled)
2693 		return;
2694 
2695 	if (signr == SIGQUIT)	/* don't care for those */
2696 		return;
2697 
2698 	ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_ANOM_ABEND);
2699 	if (unlikely(!ab))
2700 		return;
2701 	audit_log_task(ab);
2702 	audit_log_format(ab, " sig=%ld res=1", signr);
2703 	audit_log_end(ab);
2704 }
2705 
2706 /**
2707  * audit_seccomp - record information about a seccomp action
2708  * @syscall: syscall number
2709  * @signr: signal value
2710  * @code: the seccomp action
2711  *
2712  * Record the information associated with a seccomp action. Event filtering for
2713  * seccomp actions that are not to be logged is done in seccomp_log().
2714  * Therefore, this function forces auditing independent of the audit_enabled
2715  * and dummy context state because seccomp actions should be logged even when
2716  * audit is not in use.
2717  */
audit_seccomp(unsigned long syscall,long signr,int code)2718 void audit_seccomp(unsigned long syscall, long signr, int code)
2719 {
2720 	struct audit_buffer *ab;
2721 
2722 	ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_SECCOMP);
2723 	if (unlikely(!ab))
2724 		return;
2725 	audit_log_task(ab);
2726 	audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x",
2727 			 signr, syscall_get_arch(current), syscall,
2728 			 in_compat_syscall(), KSTK_EIP(current), code);
2729 	audit_log_end(ab);
2730 }
2731 
audit_seccomp_actions_logged(const char * names,const char * old_names,int res)2732 void audit_seccomp_actions_logged(const char *names, const char *old_names,
2733 				  int res)
2734 {
2735 	struct audit_buffer *ab;
2736 
2737 	if (!audit_enabled)
2738 		return;
2739 
2740 	ab = audit_log_start(audit_context(), GFP_KERNEL,
2741 			     AUDIT_CONFIG_CHANGE);
2742 	if (unlikely(!ab))
2743 		return;
2744 
2745 	audit_log_format(ab,
2746 			 "op=seccomp-logging actions=%s old-actions=%s res=%d",
2747 			 names, old_names, res);
2748 	audit_log_end(ab);
2749 }
2750 
audit_killed_trees(void)2751 struct list_head *audit_killed_trees(void)
2752 {
2753 	struct audit_context *ctx = audit_context();
2754 	if (likely(!ctx || !ctx->in_syscall))
2755 		return NULL;
2756 	return &ctx->killed_trees;
2757 }
2758