1 /* auditsc.c -- System-call auditing support 2 * Handles all system-call specific auditing features. 3 * 4 * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina. 5 * Copyright 2005 Hewlett-Packard Development Company, L.P. 6 * Copyright (C) 2005, 2006 IBM Corporation 7 * All Rights Reserved. 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or 12 * (at your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 22 * 23 * Written by Rickard E. (Rik) Faith <faith@redhat.com> 24 * 25 * Many of the ideas implemented here are from Stephen C. Tweedie, 26 * especially the idea of avoiding a copy by using getname. 27 * 28 * The method for actual interception of syscall entry and exit (not in 29 * this file -- see entry.S) is based on a GPL'd patch written by 30 * okir@suse.de and Copyright 2003 SuSE Linux AG. 31 * 32 * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>, 33 * 2006. 34 * 35 * The support of additional filter rules compares (>, <, >=, <=) was 36 * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005. 37 * 38 * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional 39 * filesystem information. 40 * 41 * Subject and object context labeling support added by <danjones@us.ibm.com> 42 * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance. 43 */ 44 45 #include <linux/init.h> 46 #include <asm/types.h> 47 #include <asm/atomic.h> 48 #include <linux/fs.h> 49 #include <linux/namei.h> 50 #include <linux/mm.h> 51 #include <linux/module.h> 52 #include <linux/mount.h> 53 #include <linux/socket.h> 54 #include <linux/mqueue.h> 55 #include <linux/audit.h> 56 #include <linux/personality.h> 57 #include <linux/time.h> 58 #include <linux/netlink.h> 59 #include <linux/compiler.h> 60 #include <asm/unistd.h> 61 #include <linux/security.h> 62 #include <linux/list.h> 63 #include <linux/tty.h> 64 #include <linux/binfmts.h> 65 #include <linux/highmem.h> 66 #include <linux/syscalls.h> 67 #include <linux/inotify.h> 68 69 #include "audit.h" 70 71 /* AUDIT_NAMES is the number of slots we reserve in the audit_context 72 * for saving names from getname(). */ 73 #define AUDIT_NAMES 20 74 75 /* Indicates that audit should log the full pathname. */ 76 #define AUDIT_NAME_FULL -1 77 78 /* no execve audit message should be longer than this (userspace limits) */ 79 #define MAX_EXECVE_AUDIT_LEN 7500 80 81 /* number of audit rules */ 82 int audit_n_rules; 83 84 /* determines whether we collect data for signals sent */ 85 int audit_signals; 86 87 /* When fs/namei.c:getname() is called, we store the pointer in name and 88 * we don't let putname() free it (instead we free all of the saved 89 * pointers at syscall exit time). 90 * 91 * Further, in fs/namei.c:path_lookup() we store the inode and device. */ 92 struct audit_names { 93 const char *name; 94 int name_len; /* number of name's characters to log */ 95 unsigned name_put; /* call __putname() for this name */ 96 unsigned long ino; 97 dev_t dev; 98 umode_t mode; 99 uid_t uid; 100 gid_t gid; 101 dev_t rdev; 102 u32 osid; 103 }; 104 105 struct audit_aux_data { 106 struct audit_aux_data *next; 107 int type; 108 }; 109 110 #define AUDIT_AUX_IPCPERM 0 111 112 /* Number of target pids per aux struct. */ 113 #define AUDIT_AUX_PIDS 16 114 115 struct audit_aux_data_mq_open { 116 struct audit_aux_data d; 117 int oflag; 118 mode_t mode; 119 struct mq_attr attr; 120 }; 121 122 struct audit_aux_data_mq_sendrecv { 123 struct audit_aux_data d; 124 mqd_t mqdes; 125 size_t msg_len; 126 unsigned int msg_prio; 127 struct timespec abs_timeout; 128 }; 129 130 struct audit_aux_data_mq_notify { 131 struct audit_aux_data d; 132 mqd_t mqdes; 133 struct sigevent notification; 134 }; 135 136 struct audit_aux_data_mq_getsetattr { 137 struct audit_aux_data d; 138 mqd_t mqdes; 139 struct mq_attr mqstat; 140 }; 141 142 struct audit_aux_data_ipcctl { 143 struct audit_aux_data d; 144 struct ipc_perm p; 145 unsigned long qbytes; 146 uid_t uid; 147 gid_t gid; 148 mode_t mode; 149 u32 osid; 150 }; 151 152 struct audit_aux_data_execve { 153 struct audit_aux_data d; 154 int argc; 155 int envc; 156 struct mm_struct *mm; 157 }; 158 159 struct audit_aux_data_socketcall { 160 struct audit_aux_data d; 161 int nargs; 162 unsigned long args[0]; 163 }; 164 165 struct audit_aux_data_sockaddr { 166 struct audit_aux_data d; 167 int len; 168 char a[0]; 169 }; 170 171 struct audit_aux_data_fd_pair { 172 struct audit_aux_data d; 173 int fd[2]; 174 }; 175 176 struct audit_aux_data_pids { 177 struct audit_aux_data d; 178 pid_t target_pid[AUDIT_AUX_PIDS]; 179 uid_t target_auid[AUDIT_AUX_PIDS]; 180 uid_t target_uid[AUDIT_AUX_PIDS]; 181 unsigned int target_sessionid[AUDIT_AUX_PIDS]; 182 u32 target_sid[AUDIT_AUX_PIDS]; 183 char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN]; 184 int pid_count; 185 }; 186 187 struct audit_tree_refs { 188 struct audit_tree_refs *next; 189 struct audit_chunk *c[31]; 190 }; 191 192 /* The per-task audit context. */ 193 struct audit_context { 194 int dummy; /* must be the first element */ 195 int in_syscall; /* 1 if task is in a syscall */ 196 enum audit_state state; 197 unsigned int serial; /* serial number for record */ 198 struct timespec ctime; /* time of syscall entry */ 199 int major; /* syscall number */ 200 unsigned long argv[4]; /* syscall arguments */ 201 int return_valid; /* return code is valid */ 202 long return_code;/* syscall return code */ 203 int auditable; /* 1 if record should be written */ 204 int name_count; 205 struct audit_names names[AUDIT_NAMES]; 206 char * filterkey; /* key for rule that triggered record */ 207 struct path pwd; 208 struct audit_context *previous; /* For nested syscalls */ 209 struct audit_aux_data *aux; 210 struct audit_aux_data *aux_pids; 211 212 /* Save things to print about task_struct */ 213 pid_t pid, ppid; 214 uid_t uid, euid, suid, fsuid; 215 gid_t gid, egid, sgid, fsgid; 216 unsigned long personality; 217 int arch; 218 219 pid_t target_pid; 220 uid_t target_auid; 221 uid_t target_uid; 222 unsigned int target_sessionid; 223 u32 target_sid; 224 char target_comm[TASK_COMM_LEN]; 225 226 struct audit_tree_refs *trees, *first_trees; 227 int tree_count; 228 229 #if AUDIT_DEBUG 230 int put_count; 231 int ino_count; 232 #endif 233 }; 234 235 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE]) 236 static inline int open_arg(int flags, int mask) 237 { 238 int n = ACC_MODE(flags); 239 if (flags & (O_TRUNC | O_CREAT)) 240 n |= AUDIT_PERM_WRITE; 241 return n & mask; 242 } 243 244 static int audit_match_perm(struct audit_context *ctx, int mask) 245 { 246 if (unlikely(!ctx)) 247 return 0; 248 249 unsigned n = ctx->major; 250 switch (audit_classify_syscall(ctx->arch, n)) { 251 case 0: /* native */ 252 if ((mask & AUDIT_PERM_WRITE) && 253 audit_match_class(AUDIT_CLASS_WRITE, n)) 254 return 1; 255 if ((mask & AUDIT_PERM_READ) && 256 audit_match_class(AUDIT_CLASS_READ, n)) 257 return 1; 258 if ((mask & AUDIT_PERM_ATTR) && 259 audit_match_class(AUDIT_CLASS_CHATTR, n)) 260 return 1; 261 return 0; 262 case 1: /* 32bit on biarch */ 263 if ((mask & AUDIT_PERM_WRITE) && 264 audit_match_class(AUDIT_CLASS_WRITE_32, n)) 265 return 1; 266 if ((mask & AUDIT_PERM_READ) && 267 audit_match_class(AUDIT_CLASS_READ_32, n)) 268 return 1; 269 if ((mask & AUDIT_PERM_ATTR) && 270 audit_match_class(AUDIT_CLASS_CHATTR_32, n)) 271 return 1; 272 return 0; 273 case 2: /* open */ 274 return mask & ACC_MODE(ctx->argv[1]); 275 case 3: /* openat */ 276 return mask & ACC_MODE(ctx->argv[2]); 277 case 4: /* socketcall */ 278 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); 279 case 5: /* execve */ 280 return mask & AUDIT_PERM_EXEC; 281 default: 282 return 0; 283 } 284 } 285 286 static int audit_match_filetype(struct audit_context *ctx, int which) 287 { 288 unsigned index = which & ~S_IFMT; 289 mode_t mode = which & S_IFMT; 290 291 if (unlikely(!ctx)) 292 return 0; 293 294 if (index >= ctx->name_count) 295 return 0; 296 if (ctx->names[index].ino == -1) 297 return 0; 298 if ((ctx->names[index].mode ^ mode) & S_IFMT) 299 return 0; 300 return 1; 301 } 302 303 /* 304 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *; 305 * ->first_trees points to its beginning, ->trees - to the current end of data. 306 * ->tree_count is the number of free entries in array pointed to by ->trees. 307 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL, 308 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously, 309 * it's going to remain 1-element for almost any setup) until we free context itself. 310 * References in it _are_ dropped - at the same time we free/drop aux stuff. 311 */ 312 313 #ifdef CONFIG_AUDIT_TREE 314 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk) 315 { 316 struct audit_tree_refs *p = ctx->trees; 317 int left = ctx->tree_count; 318 if (likely(left)) { 319 p->c[--left] = chunk; 320 ctx->tree_count = left; 321 return 1; 322 } 323 if (!p) 324 return 0; 325 p = p->next; 326 if (p) { 327 p->c[30] = chunk; 328 ctx->trees = p; 329 ctx->tree_count = 30; 330 return 1; 331 } 332 return 0; 333 } 334 335 static int grow_tree_refs(struct audit_context *ctx) 336 { 337 struct audit_tree_refs *p = ctx->trees; 338 ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL); 339 if (!ctx->trees) { 340 ctx->trees = p; 341 return 0; 342 } 343 if (p) 344 p->next = ctx->trees; 345 else 346 ctx->first_trees = ctx->trees; 347 ctx->tree_count = 31; 348 return 1; 349 } 350 #endif 351 352 static void unroll_tree_refs(struct audit_context *ctx, 353 struct audit_tree_refs *p, int count) 354 { 355 #ifdef CONFIG_AUDIT_TREE 356 struct audit_tree_refs *q; 357 int n; 358 if (!p) { 359 /* we started with empty chain */ 360 p = ctx->first_trees; 361 count = 31; 362 /* if the very first allocation has failed, nothing to do */ 363 if (!p) 364 return; 365 } 366 n = count; 367 for (q = p; q != ctx->trees; q = q->next, n = 31) { 368 while (n--) { 369 audit_put_chunk(q->c[n]); 370 q->c[n] = NULL; 371 } 372 } 373 while (n-- > ctx->tree_count) { 374 audit_put_chunk(q->c[n]); 375 q->c[n] = NULL; 376 } 377 ctx->trees = p; 378 ctx->tree_count = count; 379 #endif 380 } 381 382 static void free_tree_refs(struct audit_context *ctx) 383 { 384 struct audit_tree_refs *p, *q; 385 for (p = ctx->first_trees; p; p = q) { 386 q = p->next; 387 kfree(p); 388 } 389 } 390 391 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree) 392 { 393 #ifdef CONFIG_AUDIT_TREE 394 struct audit_tree_refs *p; 395 int n; 396 if (!tree) 397 return 0; 398 /* full ones */ 399 for (p = ctx->first_trees; p != ctx->trees; p = p->next) { 400 for (n = 0; n < 31; n++) 401 if (audit_tree_match(p->c[n], tree)) 402 return 1; 403 } 404 /* partial */ 405 if (p) { 406 for (n = ctx->tree_count; n < 31; n++) 407 if (audit_tree_match(p->c[n], tree)) 408 return 1; 409 } 410 #endif 411 return 0; 412 } 413 414 /* Determine if any context name data matches a rule's watch data */ 415 /* Compare a task_struct with an audit_rule. Return 1 on match, 0 416 * otherwise. */ 417 static int audit_filter_rules(struct task_struct *tsk, 418 struct audit_krule *rule, 419 struct audit_context *ctx, 420 struct audit_names *name, 421 enum audit_state *state) 422 { 423 int i, j, need_sid = 1; 424 u32 sid; 425 426 for (i = 0; i < rule->field_count; i++) { 427 struct audit_field *f = &rule->fields[i]; 428 int result = 0; 429 430 switch (f->type) { 431 case AUDIT_PID: 432 result = audit_comparator(tsk->pid, f->op, f->val); 433 break; 434 case AUDIT_PPID: 435 if (ctx) { 436 if (!ctx->ppid) 437 ctx->ppid = sys_getppid(); 438 result = audit_comparator(ctx->ppid, f->op, f->val); 439 } 440 break; 441 case AUDIT_UID: 442 result = audit_comparator(tsk->uid, f->op, f->val); 443 break; 444 case AUDIT_EUID: 445 result = audit_comparator(tsk->euid, f->op, f->val); 446 break; 447 case AUDIT_SUID: 448 result = audit_comparator(tsk->suid, f->op, f->val); 449 break; 450 case AUDIT_FSUID: 451 result = audit_comparator(tsk->fsuid, f->op, f->val); 452 break; 453 case AUDIT_GID: 454 result = audit_comparator(tsk->gid, f->op, f->val); 455 break; 456 case AUDIT_EGID: 457 result = audit_comparator(tsk->egid, f->op, f->val); 458 break; 459 case AUDIT_SGID: 460 result = audit_comparator(tsk->sgid, f->op, f->val); 461 break; 462 case AUDIT_FSGID: 463 result = audit_comparator(tsk->fsgid, f->op, f->val); 464 break; 465 case AUDIT_PERS: 466 result = audit_comparator(tsk->personality, f->op, f->val); 467 break; 468 case AUDIT_ARCH: 469 if (ctx) 470 result = audit_comparator(ctx->arch, f->op, f->val); 471 break; 472 473 case AUDIT_EXIT: 474 if (ctx && ctx->return_valid) 475 result = audit_comparator(ctx->return_code, f->op, f->val); 476 break; 477 case AUDIT_SUCCESS: 478 if (ctx && ctx->return_valid) { 479 if (f->val) 480 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS); 481 else 482 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE); 483 } 484 break; 485 case AUDIT_DEVMAJOR: 486 if (name) 487 result = audit_comparator(MAJOR(name->dev), 488 f->op, f->val); 489 else if (ctx) { 490 for (j = 0; j < ctx->name_count; j++) { 491 if (audit_comparator(MAJOR(ctx->names[j].dev), f->op, f->val)) { 492 ++result; 493 break; 494 } 495 } 496 } 497 break; 498 case AUDIT_DEVMINOR: 499 if (name) 500 result = audit_comparator(MINOR(name->dev), 501 f->op, f->val); 502 else if (ctx) { 503 for (j = 0; j < ctx->name_count; j++) { 504 if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) { 505 ++result; 506 break; 507 } 508 } 509 } 510 break; 511 case AUDIT_INODE: 512 if (name) 513 result = (name->ino == f->val); 514 else if (ctx) { 515 for (j = 0; j < ctx->name_count; j++) { 516 if (audit_comparator(ctx->names[j].ino, f->op, f->val)) { 517 ++result; 518 break; 519 } 520 } 521 } 522 break; 523 case AUDIT_WATCH: 524 if (name && rule->watch->ino != (unsigned long)-1) 525 result = (name->dev == rule->watch->dev && 526 name->ino == rule->watch->ino); 527 break; 528 case AUDIT_DIR: 529 if (ctx) 530 result = match_tree_refs(ctx, rule->tree); 531 break; 532 case AUDIT_LOGINUID: 533 result = 0; 534 if (ctx) 535 result = audit_comparator(tsk->loginuid, f->op, f->val); 536 break; 537 case AUDIT_SUBJ_USER: 538 case AUDIT_SUBJ_ROLE: 539 case AUDIT_SUBJ_TYPE: 540 case AUDIT_SUBJ_SEN: 541 case AUDIT_SUBJ_CLR: 542 /* NOTE: this may return negative values indicating 543 a temporary error. We simply treat this as a 544 match for now to avoid losing information that 545 may be wanted. An error message will also be 546 logged upon error */ 547 if (f->lsm_rule) { 548 if (need_sid) { 549 security_task_getsecid(tsk, &sid); 550 need_sid = 0; 551 } 552 result = security_audit_rule_match(sid, f->type, 553 f->op, 554 f->lsm_rule, 555 ctx); 556 } 557 break; 558 case AUDIT_OBJ_USER: 559 case AUDIT_OBJ_ROLE: 560 case AUDIT_OBJ_TYPE: 561 case AUDIT_OBJ_LEV_LOW: 562 case AUDIT_OBJ_LEV_HIGH: 563 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR 564 also applies here */ 565 if (f->lsm_rule) { 566 /* Find files that match */ 567 if (name) { 568 result = security_audit_rule_match( 569 name->osid, f->type, f->op, 570 f->lsm_rule, ctx); 571 } else if (ctx) { 572 for (j = 0; j < ctx->name_count; j++) { 573 if (security_audit_rule_match( 574 ctx->names[j].osid, 575 f->type, f->op, 576 f->lsm_rule, ctx)) { 577 ++result; 578 break; 579 } 580 } 581 } 582 /* Find ipc objects that match */ 583 if (ctx) { 584 struct audit_aux_data *aux; 585 for (aux = ctx->aux; aux; 586 aux = aux->next) { 587 if (aux->type == AUDIT_IPC) { 588 struct audit_aux_data_ipcctl *axi = (void *)aux; 589 if (security_audit_rule_match(axi->osid, f->type, f->op, f->lsm_rule, ctx)) { 590 ++result; 591 break; 592 } 593 } 594 } 595 } 596 } 597 break; 598 case AUDIT_ARG0: 599 case AUDIT_ARG1: 600 case AUDIT_ARG2: 601 case AUDIT_ARG3: 602 if (ctx) 603 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val); 604 break; 605 case AUDIT_FILTERKEY: 606 /* ignore this field for filtering */ 607 result = 1; 608 break; 609 case AUDIT_PERM: 610 result = audit_match_perm(ctx, f->val); 611 break; 612 case AUDIT_FILETYPE: 613 result = audit_match_filetype(ctx, f->val); 614 break; 615 } 616 617 if (!result) 618 return 0; 619 } 620 if (rule->filterkey && ctx) 621 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC); 622 switch (rule->action) { 623 case AUDIT_NEVER: *state = AUDIT_DISABLED; break; 624 case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; 625 } 626 return 1; 627 } 628 629 /* At process creation time, we can determine if system-call auditing is 630 * completely disabled for this task. Since we only have the task 631 * structure at this point, we can only check uid and gid. 632 */ 633 static enum audit_state audit_filter_task(struct task_struct *tsk) 634 { 635 struct audit_entry *e; 636 enum audit_state state; 637 638 rcu_read_lock(); 639 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { 640 if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) { 641 rcu_read_unlock(); 642 return state; 643 } 644 } 645 rcu_read_unlock(); 646 return AUDIT_BUILD_CONTEXT; 647 } 648 649 /* At syscall entry and exit time, this filter is called if the 650 * audit_state is not low enough that auditing cannot take place, but is 651 * also not high enough that we already know we have to write an audit 652 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). 653 */ 654 static enum audit_state audit_filter_syscall(struct task_struct *tsk, 655 struct audit_context *ctx, 656 struct list_head *list) 657 { 658 struct audit_entry *e; 659 enum audit_state state; 660 661 if (audit_pid && tsk->tgid == audit_pid) 662 return AUDIT_DISABLED; 663 664 rcu_read_lock(); 665 if (!list_empty(list)) { 666 int word = AUDIT_WORD(ctx->major); 667 int bit = AUDIT_BIT(ctx->major); 668 669 list_for_each_entry_rcu(e, list, list) { 670 if ((e->rule.mask[word] & bit) == bit && 671 audit_filter_rules(tsk, &e->rule, ctx, NULL, 672 &state)) { 673 rcu_read_unlock(); 674 return state; 675 } 676 } 677 } 678 rcu_read_unlock(); 679 return AUDIT_BUILD_CONTEXT; 680 } 681 682 /* At syscall exit time, this filter is called if any audit_names[] have been 683 * collected during syscall processing. We only check rules in sublists at hash 684 * buckets applicable to the inode numbers in audit_names[]. 685 * Regarding audit_state, same rules apply as for audit_filter_syscall(). 686 */ 687 enum audit_state audit_filter_inodes(struct task_struct *tsk, 688 struct audit_context *ctx) 689 { 690 int i; 691 struct audit_entry *e; 692 enum audit_state state; 693 694 if (audit_pid && tsk->tgid == audit_pid) 695 return AUDIT_DISABLED; 696 697 rcu_read_lock(); 698 for (i = 0; i < ctx->name_count; i++) { 699 int word = AUDIT_WORD(ctx->major); 700 int bit = AUDIT_BIT(ctx->major); 701 struct audit_names *n = &ctx->names[i]; 702 int h = audit_hash_ino((u32)n->ino); 703 struct list_head *list = &audit_inode_hash[h]; 704 705 if (list_empty(list)) 706 continue; 707 708 list_for_each_entry_rcu(e, list, list) { 709 if ((e->rule.mask[word] & bit) == bit && 710 audit_filter_rules(tsk, &e->rule, ctx, n, &state)) { 711 rcu_read_unlock(); 712 return state; 713 } 714 } 715 } 716 rcu_read_unlock(); 717 return AUDIT_BUILD_CONTEXT; 718 } 719 720 void audit_set_auditable(struct audit_context *ctx) 721 { 722 ctx->auditable = 1; 723 } 724 725 static inline struct audit_context *audit_get_context(struct task_struct *tsk, 726 int return_valid, 727 int return_code) 728 { 729 struct audit_context *context = tsk->audit_context; 730 731 if (likely(!context)) 732 return NULL; 733 context->return_valid = return_valid; 734 735 /* 736 * we need to fix up the return code in the audit logs if the actual 737 * return codes are later going to be fixed up by the arch specific 738 * signal handlers 739 * 740 * This is actually a test for: 741 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) || 742 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK) 743 * 744 * but is faster than a bunch of || 745 */ 746 if (unlikely(return_code <= -ERESTARTSYS) && 747 (return_code >= -ERESTART_RESTARTBLOCK) && 748 (return_code != -ENOIOCTLCMD)) 749 context->return_code = -EINTR; 750 else 751 context->return_code = return_code; 752 753 if (context->in_syscall && !context->dummy && !context->auditable) { 754 enum audit_state state; 755 756 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]); 757 if (state == AUDIT_RECORD_CONTEXT) { 758 context->auditable = 1; 759 goto get_context; 760 } 761 762 state = audit_filter_inodes(tsk, context); 763 if (state == AUDIT_RECORD_CONTEXT) 764 context->auditable = 1; 765 766 } 767 768 get_context: 769 770 tsk->audit_context = NULL; 771 return context; 772 } 773 774 static inline void audit_free_names(struct audit_context *context) 775 { 776 int i; 777 778 #if AUDIT_DEBUG == 2 779 if (context->auditable 780 ||context->put_count + context->ino_count != context->name_count) { 781 printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d" 782 " name_count=%d put_count=%d" 783 " ino_count=%d [NOT freeing]\n", 784 __FILE__, __LINE__, 785 context->serial, context->major, context->in_syscall, 786 context->name_count, context->put_count, 787 context->ino_count); 788 for (i = 0; i < context->name_count; i++) { 789 printk(KERN_ERR "names[%d] = %p = %s\n", i, 790 context->names[i].name, 791 context->names[i].name ?: "(null)"); 792 } 793 dump_stack(); 794 return; 795 } 796 #endif 797 #if AUDIT_DEBUG 798 context->put_count = 0; 799 context->ino_count = 0; 800 #endif 801 802 for (i = 0; i < context->name_count; i++) { 803 if (context->names[i].name && context->names[i].name_put) 804 __putname(context->names[i].name); 805 } 806 context->name_count = 0; 807 path_put(&context->pwd); 808 context->pwd.dentry = NULL; 809 context->pwd.mnt = NULL; 810 } 811 812 static inline void audit_free_aux(struct audit_context *context) 813 { 814 struct audit_aux_data *aux; 815 816 while ((aux = context->aux)) { 817 context->aux = aux->next; 818 kfree(aux); 819 } 820 while ((aux = context->aux_pids)) { 821 context->aux_pids = aux->next; 822 kfree(aux); 823 } 824 } 825 826 static inline void audit_zero_context(struct audit_context *context, 827 enum audit_state state) 828 { 829 memset(context, 0, sizeof(*context)); 830 context->state = state; 831 } 832 833 static inline struct audit_context *audit_alloc_context(enum audit_state state) 834 { 835 struct audit_context *context; 836 837 if (!(context = kmalloc(sizeof(*context), GFP_KERNEL))) 838 return NULL; 839 audit_zero_context(context, state); 840 return context; 841 } 842 843 /** 844 * audit_alloc - allocate an audit context block for a task 845 * @tsk: task 846 * 847 * Filter on the task information and allocate a per-task audit context 848 * if necessary. Doing so turns on system call auditing for the 849 * specified task. This is called from copy_process, so no lock is 850 * needed. 851 */ 852 int audit_alloc(struct task_struct *tsk) 853 { 854 struct audit_context *context; 855 enum audit_state state; 856 857 if (likely(!audit_ever_enabled)) 858 return 0; /* Return if not auditing. */ 859 860 state = audit_filter_task(tsk); 861 if (likely(state == AUDIT_DISABLED)) 862 return 0; 863 864 if (!(context = audit_alloc_context(state))) { 865 audit_log_lost("out of memory in audit_alloc"); 866 return -ENOMEM; 867 } 868 869 tsk->audit_context = context; 870 set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); 871 return 0; 872 } 873 874 static inline void audit_free_context(struct audit_context *context) 875 { 876 struct audit_context *previous; 877 int count = 0; 878 879 do { 880 previous = context->previous; 881 if (previous || (count && count < 10)) { 882 ++count; 883 printk(KERN_ERR "audit(:%d): major=%d name_count=%d:" 884 " freeing multiple contexts (%d)\n", 885 context->serial, context->major, 886 context->name_count, count); 887 } 888 audit_free_names(context); 889 unroll_tree_refs(context, NULL, 0); 890 free_tree_refs(context); 891 audit_free_aux(context); 892 kfree(context->filterkey); 893 kfree(context); 894 context = previous; 895 } while (context); 896 if (count >= 10) 897 printk(KERN_ERR "audit: freed %d contexts\n", count); 898 } 899 900 void audit_log_task_context(struct audit_buffer *ab) 901 { 902 char *ctx = NULL; 903 unsigned len; 904 int error; 905 u32 sid; 906 907 security_task_getsecid(current, &sid); 908 if (!sid) 909 return; 910 911 error = security_secid_to_secctx(sid, &ctx, &len); 912 if (error) { 913 if (error != -EINVAL) 914 goto error_path; 915 return; 916 } 917 918 audit_log_format(ab, " subj=%s", ctx); 919 security_release_secctx(ctx, len); 920 return; 921 922 error_path: 923 audit_panic("error in audit_log_task_context"); 924 return; 925 } 926 927 EXPORT_SYMBOL(audit_log_task_context); 928 929 static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk) 930 { 931 char name[sizeof(tsk->comm)]; 932 struct mm_struct *mm = tsk->mm; 933 struct vm_area_struct *vma; 934 935 /* tsk == current */ 936 937 get_task_comm(name, tsk); 938 audit_log_format(ab, " comm="); 939 audit_log_untrustedstring(ab, name); 940 941 if (mm) { 942 down_read(&mm->mmap_sem); 943 vma = mm->mmap; 944 while (vma) { 945 if ((vma->vm_flags & VM_EXECUTABLE) && 946 vma->vm_file) { 947 audit_log_d_path(ab, "exe=", 948 &vma->vm_file->f_path); 949 break; 950 } 951 vma = vma->vm_next; 952 } 953 up_read(&mm->mmap_sem); 954 } 955 audit_log_task_context(ab); 956 } 957 958 static int audit_log_pid_context(struct audit_context *context, pid_t pid, 959 uid_t auid, uid_t uid, unsigned int sessionid, 960 u32 sid, char *comm) 961 { 962 struct audit_buffer *ab; 963 char *ctx = NULL; 964 u32 len; 965 int rc = 0; 966 967 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); 968 if (!ab) 969 return rc; 970 971 audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid, 972 uid, sessionid); 973 if (security_secid_to_secctx(sid, &ctx, &len)) { 974 audit_log_format(ab, " obj=(none)"); 975 rc = 1; 976 } else { 977 audit_log_format(ab, " obj=%s", ctx); 978 security_release_secctx(ctx, len); 979 } 980 audit_log_format(ab, " ocomm="); 981 audit_log_untrustedstring(ab, comm); 982 audit_log_end(ab); 983 984 return rc; 985 } 986 987 /* 988 * to_send and len_sent accounting are very loose estimates. We aren't 989 * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being 990 * within about 500 bytes (next page boundry) 991 * 992 * why snprintf? an int is up to 12 digits long. if we just assumed when 993 * logging that a[%d]= was going to be 16 characters long we would be wasting 994 * space in every audit message. In one 7500 byte message we can log up to 995 * about 1000 min size arguments. That comes down to about 50% waste of space 996 * if we didn't do the snprintf to find out how long arg_num_len was. 997 */ 998 static int audit_log_single_execve_arg(struct audit_context *context, 999 struct audit_buffer **ab, 1000 int arg_num, 1001 size_t *len_sent, 1002 const char __user *p, 1003 char *buf) 1004 { 1005 char arg_num_len_buf[12]; 1006 const char __user *tmp_p = p; 1007 /* how many digits are in arg_num? 3 is the length of a=\n */ 1008 size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 3; 1009 size_t len, len_left, to_send; 1010 size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN; 1011 unsigned int i, has_cntl = 0, too_long = 0; 1012 int ret; 1013 1014 /* strnlen_user includes the null we don't want to send */ 1015 len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1; 1016 1017 /* 1018 * We just created this mm, if we can't find the strings 1019 * we just copied into it something is _very_ wrong. Similar 1020 * for strings that are too long, we should not have created 1021 * any. 1022 */ 1023 if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) { 1024 WARN_ON(1); 1025 send_sig(SIGKILL, current, 0); 1026 return -1; 1027 } 1028 1029 /* walk the whole argument looking for non-ascii chars */ 1030 do { 1031 if (len_left > MAX_EXECVE_AUDIT_LEN) 1032 to_send = MAX_EXECVE_AUDIT_LEN; 1033 else 1034 to_send = len_left; 1035 ret = copy_from_user(buf, tmp_p, to_send); 1036 /* 1037 * There is no reason for this copy to be short. We just 1038 * copied them here, and the mm hasn't been exposed to user- 1039 * space yet. 1040 */ 1041 if (ret) { 1042 WARN_ON(1); 1043 send_sig(SIGKILL, current, 0); 1044 return -1; 1045 } 1046 buf[to_send] = '\0'; 1047 has_cntl = audit_string_contains_control(buf, to_send); 1048 if (has_cntl) { 1049 /* 1050 * hex messages get logged as 2 bytes, so we can only 1051 * send half as much in each message 1052 */ 1053 max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2; 1054 break; 1055 } 1056 len_left -= to_send; 1057 tmp_p += to_send; 1058 } while (len_left > 0); 1059 1060 len_left = len; 1061 1062 if (len > max_execve_audit_len) 1063 too_long = 1; 1064 1065 /* rewalk the argument actually logging the message */ 1066 for (i = 0; len_left > 0; i++) { 1067 int room_left; 1068 1069 if (len_left > max_execve_audit_len) 1070 to_send = max_execve_audit_len; 1071 else 1072 to_send = len_left; 1073 1074 /* do we have space left to send this argument in this ab? */ 1075 room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent; 1076 if (has_cntl) 1077 room_left -= (to_send * 2); 1078 else 1079 room_left -= to_send; 1080 if (room_left < 0) { 1081 *len_sent = 0; 1082 audit_log_end(*ab); 1083 *ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE); 1084 if (!*ab) 1085 return 0; 1086 } 1087 1088 /* 1089 * first record needs to say how long the original string was 1090 * so we can be sure nothing was lost. 1091 */ 1092 if ((i == 0) && (too_long)) 1093 audit_log_format(*ab, "a%d_len=%zu ", arg_num, 1094 has_cntl ? 2*len : len); 1095 1096 /* 1097 * normally arguments are small enough to fit and we already 1098 * filled buf above when we checked for control characters 1099 * so don't bother with another copy_from_user 1100 */ 1101 if (len >= max_execve_audit_len) 1102 ret = copy_from_user(buf, p, to_send); 1103 else 1104 ret = 0; 1105 if (ret) { 1106 WARN_ON(1); 1107 send_sig(SIGKILL, current, 0); 1108 return -1; 1109 } 1110 buf[to_send] = '\0'; 1111 1112 /* actually log it */ 1113 audit_log_format(*ab, "a%d", arg_num); 1114 if (too_long) 1115 audit_log_format(*ab, "[%d]", i); 1116 audit_log_format(*ab, "="); 1117 if (has_cntl) 1118 audit_log_n_hex(*ab, buf, to_send); 1119 else 1120 audit_log_format(*ab, "\"%s\"", buf); 1121 audit_log_format(*ab, "\n"); 1122 1123 p += to_send; 1124 len_left -= to_send; 1125 *len_sent += arg_num_len; 1126 if (has_cntl) 1127 *len_sent += to_send * 2; 1128 else 1129 *len_sent += to_send; 1130 } 1131 /* include the null we didn't log */ 1132 return len + 1; 1133 } 1134 1135 static void audit_log_execve_info(struct audit_context *context, 1136 struct audit_buffer **ab, 1137 struct audit_aux_data_execve *axi) 1138 { 1139 int i; 1140 size_t len, len_sent = 0; 1141 const char __user *p; 1142 char *buf; 1143 1144 if (axi->mm != current->mm) 1145 return; /* execve failed, no additional info */ 1146 1147 p = (const char __user *)axi->mm->arg_start; 1148 1149 audit_log_format(*ab, "argc=%d ", axi->argc); 1150 1151 /* 1152 * we need some kernel buffer to hold the userspace args. Just 1153 * allocate one big one rather than allocating one of the right size 1154 * for every single argument inside audit_log_single_execve_arg() 1155 * should be <8k allocation so should be pretty safe. 1156 */ 1157 buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL); 1158 if (!buf) { 1159 audit_panic("out of memory for argv string\n"); 1160 return; 1161 } 1162 1163 for (i = 0; i < axi->argc; i++) { 1164 len = audit_log_single_execve_arg(context, ab, i, 1165 &len_sent, p, buf); 1166 if (len <= 0) 1167 break; 1168 p += len; 1169 } 1170 kfree(buf); 1171 } 1172 1173 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk) 1174 { 1175 int i, call_panic = 0; 1176 struct audit_buffer *ab; 1177 struct audit_aux_data *aux; 1178 const char *tty; 1179 1180 /* tsk == current */ 1181 context->pid = tsk->pid; 1182 if (!context->ppid) 1183 context->ppid = sys_getppid(); 1184 context->uid = tsk->uid; 1185 context->gid = tsk->gid; 1186 context->euid = tsk->euid; 1187 context->suid = tsk->suid; 1188 context->fsuid = tsk->fsuid; 1189 context->egid = tsk->egid; 1190 context->sgid = tsk->sgid; 1191 context->fsgid = tsk->fsgid; 1192 context->personality = tsk->personality; 1193 1194 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); 1195 if (!ab) 1196 return; /* audit_panic has been called */ 1197 audit_log_format(ab, "arch=%x syscall=%d", 1198 context->arch, context->major); 1199 if (context->personality != PER_LINUX) 1200 audit_log_format(ab, " per=%lx", context->personality); 1201 if (context->return_valid) 1202 audit_log_format(ab, " success=%s exit=%ld", 1203 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", 1204 context->return_code); 1205 1206 mutex_lock(&tty_mutex); 1207 read_lock(&tasklist_lock); 1208 if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name) 1209 tty = tsk->signal->tty->name; 1210 else 1211 tty = "(none)"; 1212 read_unlock(&tasklist_lock); 1213 audit_log_format(ab, 1214 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d" 1215 " ppid=%d pid=%d auid=%u uid=%u gid=%u" 1216 " euid=%u suid=%u fsuid=%u" 1217 " egid=%u sgid=%u fsgid=%u tty=%s ses=%u", 1218 context->argv[0], 1219 context->argv[1], 1220 context->argv[2], 1221 context->argv[3], 1222 context->name_count, 1223 context->ppid, 1224 context->pid, 1225 tsk->loginuid, 1226 context->uid, 1227 context->gid, 1228 context->euid, context->suid, context->fsuid, 1229 context->egid, context->sgid, context->fsgid, tty, 1230 tsk->sessionid); 1231 1232 mutex_unlock(&tty_mutex); 1233 1234 audit_log_task_info(ab, tsk); 1235 if (context->filterkey) { 1236 audit_log_format(ab, " key="); 1237 audit_log_untrustedstring(ab, context->filterkey); 1238 } else 1239 audit_log_format(ab, " key=(null)"); 1240 audit_log_end(ab); 1241 1242 for (aux = context->aux; aux; aux = aux->next) { 1243 1244 ab = audit_log_start(context, GFP_KERNEL, aux->type); 1245 if (!ab) 1246 continue; /* audit_panic has been called */ 1247 1248 switch (aux->type) { 1249 case AUDIT_MQ_OPEN: { 1250 struct audit_aux_data_mq_open *axi = (void *)aux; 1251 audit_log_format(ab, 1252 "oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld " 1253 "mq_msgsize=%ld mq_curmsgs=%ld", 1254 axi->oflag, axi->mode, axi->attr.mq_flags, 1255 axi->attr.mq_maxmsg, axi->attr.mq_msgsize, 1256 axi->attr.mq_curmsgs); 1257 break; } 1258 1259 case AUDIT_MQ_SENDRECV: { 1260 struct audit_aux_data_mq_sendrecv *axi = (void *)aux; 1261 audit_log_format(ab, 1262 "mqdes=%d msg_len=%zd msg_prio=%u " 1263 "abs_timeout_sec=%ld abs_timeout_nsec=%ld", 1264 axi->mqdes, axi->msg_len, axi->msg_prio, 1265 axi->abs_timeout.tv_sec, axi->abs_timeout.tv_nsec); 1266 break; } 1267 1268 case AUDIT_MQ_NOTIFY: { 1269 struct audit_aux_data_mq_notify *axi = (void *)aux; 1270 audit_log_format(ab, 1271 "mqdes=%d sigev_signo=%d", 1272 axi->mqdes, 1273 axi->notification.sigev_signo); 1274 break; } 1275 1276 case AUDIT_MQ_GETSETATTR: { 1277 struct audit_aux_data_mq_getsetattr *axi = (void *)aux; 1278 audit_log_format(ab, 1279 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld " 1280 "mq_curmsgs=%ld ", 1281 axi->mqdes, 1282 axi->mqstat.mq_flags, axi->mqstat.mq_maxmsg, 1283 axi->mqstat.mq_msgsize, axi->mqstat.mq_curmsgs); 1284 break; } 1285 1286 case AUDIT_IPC: { 1287 struct audit_aux_data_ipcctl *axi = (void *)aux; 1288 audit_log_format(ab, 1289 "ouid=%u ogid=%u mode=%#o", 1290 axi->uid, axi->gid, axi->mode); 1291 if (axi->osid != 0) { 1292 char *ctx = NULL; 1293 u32 len; 1294 if (security_secid_to_secctx( 1295 axi->osid, &ctx, &len)) { 1296 audit_log_format(ab, " osid=%u", 1297 axi->osid); 1298 call_panic = 1; 1299 } else { 1300 audit_log_format(ab, " obj=%s", ctx); 1301 security_release_secctx(ctx, len); 1302 } 1303 } 1304 break; } 1305 1306 case AUDIT_IPC_SET_PERM: { 1307 struct audit_aux_data_ipcctl *axi = (void *)aux; 1308 audit_log_format(ab, 1309 "qbytes=%lx ouid=%u ogid=%u mode=%#o", 1310 axi->qbytes, axi->uid, axi->gid, axi->mode); 1311 break; } 1312 1313 case AUDIT_EXECVE: { 1314 struct audit_aux_data_execve *axi = (void *)aux; 1315 audit_log_execve_info(context, &ab, axi); 1316 break; } 1317 1318 case AUDIT_SOCKETCALL: { 1319 struct audit_aux_data_socketcall *axs = (void *)aux; 1320 audit_log_format(ab, "nargs=%d", axs->nargs); 1321 for (i=0; i<axs->nargs; i++) 1322 audit_log_format(ab, " a%d=%lx", i, axs->args[i]); 1323 break; } 1324 1325 case AUDIT_SOCKADDR: { 1326 struct audit_aux_data_sockaddr *axs = (void *)aux; 1327 1328 audit_log_format(ab, "saddr="); 1329 audit_log_n_hex(ab, axs->a, axs->len); 1330 break; } 1331 1332 case AUDIT_FD_PAIR: { 1333 struct audit_aux_data_fd_pair *axs = (void *)aux; 1334 audit_log_format(ab, "fd0=%d fd1=%d", axs->fd[0], axs->fd[1]); 1335 break; } 1336 1337 } 1338 audit_log_end(ab); 1339 } 1340 1341 for (aux = context->aux_pids; aux; aux = aux->next) { 1342 struct audit_aux_data_pids *axs = (void *)aux; 1343 1344 for (i = 0; i < axs->pid_count; i++) 1345 if (audit_log_pid_context(context, axs->target_pid[i], 1346 axs->target_auid[i], 1347 axs->target_uid[i], 1348 axs->target_sessionid[i], 1349 axs->target_sid[i], 1350 axs->target_comm[i])) 1351 call_panic = 1; 1352 } 1353 1354 if (context->target_pid && 1355 audit_log_pid_context(context, context->target_pid, 1356 context->target_auid, context->target_uid, 1357 context->target_sessionid, 1358 context->target_sid, context->target_comm)) 1359 call_panic = 1; 1360 1361 if (context->pwd.dentry && context->pwd.mnt) { 1362 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); 1363 if (ab) { 1364 audit_log_d_path(ab, "cwd=", &context->pwd); 1365 audit_log_end(ab); 1366 } 1367 } 1368 for (i = 0; i < context->name_count; i++) { 1369 struct audit_names *n = &context->names[i]; 1370 1371 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH); 1372 if (!ab) 1373 continue; /* audit_panic has been called */ 1374 1375 audit_log_format(ab, "item=%d", i); 1376 1377 if (n->name) { 1378 switch(n->name_len) { 1379 case AUDIT_NAME_FULL: 1380 /* log the full path */ 1381 audit_log_format(ab, " name="); 1382 audit_log_untrustedstring(ab, n->name); 1383 break; 1384 case 0: 1385 /* name was specified as a relative path and the 1386 * directory component is the cwd */ 1387 audit_log_d_path(ab, " name=", &context->pwd); 1388 break; 1389 default: 1390 /* log the name's directory component */ 1391 audit_log_format(ab, " name="); 1392 audit_log_n_untrustedstring(ab, n->name, 1393 n->name_len); 1394 } 1395 } else 1396 audit_log_format(ab, " name=(null)"); 1397 1398 if (n->ino != (unsigned long)-1) { 1399 audit_log_format(ab, " inode=%lu" 1400 " dev=%02x:%02x mode=%#o" 1401 " ouid=%u ogid=%u rdev=%02x:%02x", 1402 n->ino, 1403 MAJOR(n->dev), 1404 MINOR(n->dev), 1405 n->mode, 1406 n->uid, 1407 n->gid, 1408 MAJOR(n->rdev), 1409 MINOR(n->rdev)); 1410 } 1411 if (n->osid != 0) { 1412 char *ctx = NULL; 1413 u32 len; 1414 if (security_secid_to_secctx( 1415 n->osid, &ctx, &len)) { 1416 audit_log_format(ab, " osid=%u", n->osid); 1417 call_panic = 2; 1418 } else { 1419 audit_log_format(ab, " obj=%s", ctx); 1420 security_release_secctx(ctx, len); 1421 } 1422 } 1423 1424 audit_log_end(ab); 1425 } 1426 1427 /* Send end of event record to help user space know we are finished */ 1428 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); 1429 if (ab) 1430 audit_log_end(ab); 1431 if (call_panic) 1432 audit_panic("error converting sid to string"); 1433 } 1434 1435 /** 1436 * audit_free - free a per-task audit context 1437 * @tsk: task whose audit context block to free 1438 * 1439 * Called from copy_process and do_exit 1440 */ 1441 void audit_free(struct task_struct *tsk) 1442 { 1443 struct audit_context *context; 1444 1445 context = audit_get_context(tsk, 0, 0); 1446 if (likely(!context)) 1447 return; 1448 1449 /* Check for system calls that do not go through the exit 1450 * function (e.g., exit_group), then free context block. 1451 * We use GFP_ATOMIC here because we might be doing this 1452 * in the context of the idle thread */ 1453 /* that can happen only if we are called from do_exit() */ 1454 if (context->in_syscall && context->auditable) 1455 audit_log_exit(context, tsk); 1456 1457 audit_free_context(context); 1458 } 1459 1460 /** 1461 * audit_syscall_entry - fill in an audit record at syscall entry 1462 * @tsk: task being audited 1463 * @arch: architecture type 1464 * @major: major syscall type (function) 1465 * @a1: additional syscall register 1 1466 * @a2: additional syscall register 2 1467 * @a3: additional syscall register 3 1468 * @a4: additional syscall register 4 1469 * 1470 * Fill in audit context at syscall entry. This only happens if the 1471 * audit context was created when the task was created and the state or 1472 * filters demand the audit context be built. If the state from the 1473 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, 1474 * then the record will be written at syscall exit time (otherwise, it 1475 * will only be written if another part of the kernel requests that it 1476 * be written). 1477 */ 1478 void audit_syscall_entry(int arch, int major, 1479 unsigned long a1, unsigned long a2, 1480 unsigned long a3, unsigned long a4) 1481 { 1482 struct task_struct *tsk = current; 1483 struct audit_context *context = tsk->audit_context; 1484 enum audit_state state; 1485 1486 if (unlikely(!context)) 1487 return; 1488 1489 /* 1490 * This happens only on certain architectures that make system 1491 * calls in kernel_thread via the entry.S interface, instead of 1492 * with direct calls. (If you are porting to a new 1493 * architecture, hitting this condition can indicate that you 1494 * got the _exit/_leave calls backward in entry.S.) 1495 * 1496 * i386 no 1497 * x86_64 no 1498 * ppc64 yes (see arch/powerpc/platforms/iseries/misc.S) 1499 * 1500 * This also happens with vm86 emulation in a non-nested manner 1501 * (entries without exits), so this case must be caught. 1502 */ 1503 if (context->in_syscall) { 1504 struct audit_context *newctx; 1505 1506 #if AUDIT_DEBUG 1507 printk(KERN_ERR 1508 "audit(:%d) pid=%d in syscall=%d;" 1509 " entering syscall=%d\n", 1510 context->serial, tsk->pid, context->major, major); 1511 #endif 1512 newctx = audit_alloc_context(context->state); 1513 if (newctx) { 1514 newctx->previous = context; 1515 context = newctx; 1516 tsk->audit_context = newctx; 1517 } else { 1518 /* If we can't alloc a new context, the best we 1519 * can do is to leak memory (any pending putname 1520 * will be lost). The only other alternative is 1521 * to abandon auditing. */ 1522 audit_zero_context(context, context->state); 1523 } 1524 } 1525 BUG_ON(context->in_syscall || context->name_count); 1526 1527 if (!audit_enabled) 1528 return; 1529 1530 context->arch = arch; 1531 context->major = major; 1532 context->argv[0] = a1; 1533 context->argv[1] = a2; 1534 context->argv[2] = a3; 1535 context->argv[3] = a4; 1536 1537 state = context->state; 1538 context->dummy = !audit_n_rules; 1539 if (!context->dummy && (state == AUDIT_SETUP_CONTEXT || state == AUDIT_BUILD_CONTEXT)) 1540 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]); 1541 if (likely(state == AUDIT_DISABLED)) 1542 return; 1543 1544 context->serial = 0; 1545 context->ctime = CURRENT_TIME; 1546 context->in_syscall = 1; 1547 context->auditable = !!(state == AUDIT_RECORD_CONTEXT); 1548 context->ppid = 0; 1549 } 1550 1551 /** 1552 * audit_syscall_exit - deallocate audit context after a system call 1553 * @tsk: task being audited 1554 * @valid: success/failure flag 1555 * @return_code: syscall return value 1556 * 1557 * Tear down after system call. If the audit context has been marked as 1558 * auditable (either because of the AUDIT_RECORD_CONTEXT state from 1559 * filtering, or because some other part of the kernel write an audit 1560 * message), then write out the syscall information. In call cases, 1561 * free the names stored from getname(). 1562 */ 1563 void audit_syscall_exit(int valid, long return_code) 1564 { 1565 struct task_struct *tsk = current; 1566 struct audit_context *context; 1567 1568 context = audit_get_context(tsk, valid, return_code); 1569 1570 if (likely(!context)) 1571 return; 1572 1573 if (context->in_syscall && context->auditable) 1574 audit_log_exit(context, tsk); 1575 1576 context->in_syscall = 0; 1577 context->auditable = 0; 1578 1579 if (context->previous) { 1580 struct audit_context *new_context = context->previous; 1581 context->previous = NULL; 1582 audit_free_context(context); 1583 tsk->audit_context = new_context; 1584 } else { 1585 audit_free_names(context); 1586 unroll_tree_refs(context, NULL, 0); 1587 audit_free_aux(context); 1588 context->aux = NULL; 1589 context->aux_pids = NULL; 1590 context->target_pid = 0; 1591 context->target_sid = 0; 1592 kfree(context->filterkey); 1593 context->filterkey = NULL; 1594 tsk->audit_context = context; 1595 } 1596 } 1597 1598 static inline void handle_one(const struct inode *inode) 1599 { 1600 #ifdef CONFIG_AUDIT_TREE 1601 struct audit_context *context; 1602 struct audit_tree_refs *p; 1603 struct audit_chunk *chunk; 1604 int count; 1605 if (likely(list_empty(&inode->inotify_watches))) 1606 return; 1607 context = current->audit_context; 1608 p = context->trees; 1609 count = context->tree_count; 1610 rcu_read_lock(); 1611 chunk = audit_tree_lookup(inode); 1612 rcu_read_unlock(); 1613 if (!chunk) 1614 return; 1615 if (likely(put_tree_ref(context, chunk))) 1616 return; 1617 if (unlikely(!grow_tree_refs(context))) { 1618 printk(KERN_WARNING "out of memory, audit has lost a tree reference\n"); 1619 audit_set_auditable(context); 1620 audit_put_chunk(chunk); 1621 unroll_tree_refs(context, p, count); 1622 return; 1623 } 1624 put_tree_ref(context, chunk); 1625 #endif 1626 } 1627 1628 static void handle_path(const struct dentry *dentry) 1629 { 1630 #ifdef CONFIG_AUDIT_TREE 1631 struct audit_context *context; 1632 struct audit_tree_refs *p; 1633 const struct dentry *d, *parent; 1634 struct audit_chunk *drop; 1635 unsigned long seq; 1636 int count; 1637 1638 context = current->audit_context; 1639 p = context->trees; 1640 count = context->tree_count; 1641 retry: 1642 drop = NULL; 1643 d = dentry; 1644 rcu_read_lock(); 1645 seq = read_seqbegin(&rename_lock); 1646 for(;;) { 1647 struct inode *inode = d->d_inode; 1648 if (inode && unlikely(!list_empty(&inode->inotify_watches))) { 1649 struct audit_chunk *chunk; 1650 chunk = audit_tree_lookup(inode); 1651 if (chunk) { 1652 if (unlikely(!put_tree_ref(context, chunk))) { 1653 drop = chunk; 1654 break; 1655 } 1656 } 1657 } 1658 parent = d->d_parent; 1659 if (parent == d) 1660 break; 1661 d = parent; 1662 } 1663 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */ 1664 rcu_read_unlock(); 1665 if (!drop) { 1666 /* just a race with rename */ 1667 unroll_tree_refs(context, p, count); 1668 goto retry; 1669 } 1670 audit_put_chunk(drop); 1671 if (grow_tree_refs(context)) { 1672 /* OK, got more space */ 1673 unroll_tree_refs(context, p, count); 1674 goto retry; 1675 } 1676 /* too bad */ 1677 printk(KERN_WARNING 1678 "out of memory, audit has lost a tree reference\n"); 1679 unroll_tree_refs(context, p, count); 1680 audit_set_auditable(context); 1681 return; 1682 } 1683 rcu_read_unlock(); 1684 #endif 1685 } 1686 1687 /** 1688 * audit_getname - add a name to the list 1689 * @name: name to add 1690 * 1691 * Add a name to the list of audit names for this context. 1692 * Called from fs/namei.c:getname(). 1693 */ 1694 void __audit_getname(const char *name) 1695 { 1696 struct audit_context *context = current->audit_context; 1697 1698 if (IS_ERR(name) || !name) 1699 return; 1700 1701 if (!context->in_syscall) { 1702 #if AUDIT_DEBUG == 2 1703 printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n", 1704 __FILE__, __LINE__, context->serial, name); 1705 dump_stack(); 1706 #endif 1707 return; 1708 } 1709 BUG_ON(context->name_count >= AUDIT_NAMES); 1710 context->names[context->name_count].name = name; 1711 context->names[context->name_count].name_len = AUDIT_NAME_FULL; 1712 context->names[context->name_count].name_put = 1; 1713 context->names[context->name_count].ino = (unsigned long)-1; 1714 context->names[context->name_count].osid = 0; 1715 ++context->name_count; 1716 if (!context->pwd.dentry) { 1717 read_lock(¤t->fs->lock); 1718 context->pwd = current->fs->pwd; 1719 path_get(¤t->fs->pwd); 1720 read_unlock(¤t->fs->lock); 1721 } 1722 1723 } 1724 1725 /* audit_putname - intercept a putname request 1726 * @name: name to intercept and delay for putname 1727 * 1728 * If we have stored the name from getname in the audit context, 1729 * then we delay the putname until syscall exit. 1730 * Called from include/linux/fs.h:putname(). 1731 */ 1732 void audit_putname(const char *name) 1733 { 1734 struct audit_context *context = current->audit_context; 1735 1736 BUG_ON(!context); 1737 if (!context->in_syscall) { 1738 #if AUDIT_DEBUG == 2 1739 printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n", 1740 __FILE__, __LINE__, context->serial, name); 1741 if (context->name_count) { 1742 int i; 1743 for (i = 0; i < context->name_count; i++) 1744 printk(KERN_ERR "name[%d] = %p = %s\n", i, 1745 context->names[i].name, 1746 context->names[i].name ?: "(null)"); 1747 } 1748 #endif 1749 __putname(name); 1750 } 1751 #if AUDIT_DEBUG 1752 else { 1753 ++context->put_count; 1754 if (context->put_count > context->name_count) { 1755 printk(KERN_ERR "%s:%d(:%d): major=%d" 1756 " in_syscall=%d putname(%p) name_count=%d" 1757 " put_count=%d\n", 1758 __FILE__, __LINE__, 1759 context->serial, context->major, 1760 context->in_syscall, name, context->name_count, 1761 context->put_count); 1762 dump_stack(); 1763 } 1764 } 1765 #endif 1766 } 1767 1768 static int audit_inc_name_count(struct audit_context *context, 1769 const struct inode *inode) 1770 { 1771 if (context->name_count >= AUDIT_NAMES) { 1772 if (inode) 1773 printk(KERN_DEBUG "name_count maxed, losing inode data: " 1774 "dev=%02x:%02x, inode=%lu\n", 1775 MAJOR(inode->i_sb->s_dev), 1776 MINOR(inode->i_sb->s_dev), 1777 inode->i_ino); 1778 1779 else 1780 printk(KERN_DEBUG "name_count maxed, losing inode data\n"); 1781 return 1; 1782 } 1783 context->name_count++; 1784 #if AUDIT_DEBUG 1785 context->ino_count++; 1786 #endif 1787 return 0; 1788 } 1789 1790 /* Copy inode data into an audit_names. */ 1791 static void audit_copy_inode(struct audit_names *name, const struct inode *inode) 1792 { 1793 name->ino = inode->i_ino; 1794 name->dev = inode->i_sb->s_dev; 1795 name->mode = inode->i_mode; 1796 name->uid = inode->i_uid; 1797 name->gid = inode->i_gid; 1798 name->rdev = inode->i_rdev; 1799 security_inode_getsecid(inode, &name->osid); 1800 } 1801 1802 /** 1803 * audit_inode - store the inode and device from a lookup 1804 * @name: name being audited 1805 * @dentry: dentry being audited 1806 * 1807 * Called from fs/namei.c:path_lookup(). 1808 */ 1809 void __audit_inode(const char *name, const struct dentry *dentry) 1810 { 1811 int idx; 1812 struct audit_context *context = current->audit_context; 1813 const struct inode *inode = dentry->d_inode; 1814 1815 if (!context->in_syscall) 1816 return; 1817 if (context->name_count 1818 && context->names[context->name_count-1].name 1819 && context->names[context->name_count-1].name == name) 1820 idx = context->name_count - 1; 1821 else if (context->name_count > 1 1822 && context->names[context->name_count-2].name 1823 && context->names[context->name_count-2].name == name) 1824 idx = context->name_count - 2; 1825 else { 1826 /* FIXME: how much do we care about inodes that have no 1827 * associated name? */ 1828 if (audit_inc_name_count(context, inode)) 1829 return; 1830 idx = context->name_count - 1; 1831 context->names[idx].name = NULL; 1832 } 1833 handle_path(dentry); 1834 audit_copy_inode(&context->names[idx], inode); 1835 } 1836 1837 /** 1838 * audit_inode_child - collect inode info for created/removed objects 1839 * @dname: inode's dentry name 1840 * @dentry: dentry being audited 1841 * @parent: inode of dentry parent 1842 * 1843 * For syscalls that create or remove filesystem objects, audit_inode 1844 * can only collect information for the filesystem object's parent. 1845 * This call updates the audit context with the child's information. 1846 * Syscalls that create a new filesystem object must be hooked after 1847 * the object is created. Syscalls that remove a filesystem object 1848 * must be hooked prior, in order to capture the target inode during 1849 * unsuccessful attempts. 1850 */ 1851 void __audit_inode_child(const char *dname, const struct dentry *dentry, 1852 const struct inode *parent) 1853 { 1854 int idx; 1855 struct audit_context *context = current->audit_context; 1856 const char *found_parent = NULL, *found_child = NULL; 1857 const struct inode *inode = dentry->d_inode; 1858 int dirlen = 0; 1859 1860 if (!context->in_syscall) 1861 return; 1862 1863 if (inode) 1864 handle_one(inode); 1865 /* determine matching parent */ 1866 if (!dname) 1867 goto add_names; 1868 1869 /* parent is more likely, look for it first */ 1870 for (idx = 0; idx < context->name_count; idx++) { 1871 struct audit_names *n = &context->names[idx]; 1872 1873 if (!n->name) 1874 continue; 1875 1876 if (n->ino == parent->i_ino && 1877 !audit_compare_dname_path(dname, n->name, &dirlen)) { 1878 n->name_len = dirlen; /* update parent data in place */ 1879 found_parent = n->name; 1880 goto add_names; 1881 } 1882 } 1883 1884 /* no matching parent, look for matching child */ 1885 for (idx = 0; idx < context->name_count; idx++) { 1886 struct audit_names *n = &context->names[idx]; 1887 1888 if (!n->name) 1889 continue; 1890 1891 /* strcmp() is the more likely scenario */ 1892 if (!strcmp(dname, n->name) || 1893 !audit_compare_dname_path(dname, n->name, &dirlen)) { 1894 if (inode) 1895 audit_copy_inode(n, inode); 1896 else 1897 n->ino = (unsigned long)-1; 1898 found_child = n->name; 1899 goto add_names; 1900 } 1901 } 1902 1903 add_names: 1904 if (!found_parent) { 1905 if (audit_inc_name_count(context, parent)) 1906 return; 1907 idx = context->name_count - 1; 1908 context->names[idx].name = NULL; 1909 audit_copy_inode(&context->names[idx], parent); 1910 } 1911 1912 if (!found_child) { 1913 if (audit_inc_name_count(context, inode)) 1914 return; 1915 idx = context->name_count - 1; 1916 1917 /* Re-use the name belonging to the slot for a matching parent 1918 * directory. All names for this context are relinquished in 1919 * audit_free_names() */ 1920 if (found_parent) { 1921 context->names[idx].name = found_parent; 1922 context->names[idx].name_len = AUDIT_NAME_FULL; 1923 /* don't call __putname() */ 1924 context->names[idx].name_put = 0; 1925 } else { 1926 context->names[idx].name = NULL; 1927 } 1928 1929 if (inode) 1930 audit_copy_inode(&context->names[idx], inode); 1931 else 1932 context->names[idx].ino = (unsigned long)-1; 1933 } 1934 } 1935 EXPORT_SYMBOL_GPL(__audit_inode_child); 1936 1937 /** 1938 * auditsc_get_stamp - get local copies of audit_context values 1939 * @ctx: audit_context for the task 1940 * @t: timespec to store time recorded in the audit_context 1941 * @serial: serial value that is recorded in the audit_context 1942 * 1943 * Also sets the context as auditable. 1944 */ 1945 void auditsc_get_stamp(struct audit_context *ctx, 1946 struct timespec *t, unsigned int *serial) 1947 { 1948 if (!ctx->serial) 1949 ctx->serial = audit_serial(); 1950 t->tv_sec = ctx->ctime.tv_sec; 1951 t->tv_nsec = ctx->ctime.tv_nsec; 1952 *serial = ctx->serial; 1953 ctx->auditable = 1; 1954 } 1955 1956 /* global counter which is incremented every time something logs in */ 1957 static atomic_t session_id = ATOMIC_INIT(0); 1958 1959 /** 1960 * audit_set_loginuid - set a task's audit_context loginuid 1961 * @task: task whose audit context is being modified 1962 * @loginuid: loginuid value 1963 * 1964 * Returns 0. 1965 * 1966 * Called (set) from fs/proc/base.c::proc_loginuid_write(). 1967 */ 1968 int audit_set_loginuid(struct task_struct *task, uid_t loginuid) 1969 { 1970 unsigned int sessionid = atomic_inc_return(&session_id); 1971 struct audit_context *context = task->audit_context; 1972 1973 if (context && context->in_syscall) { 1974 struct audit_buffer *ab; 1975 1976 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); 1977 if (ab) { 1978 audit_log_format(ab, "login pid=%d uid=%u " 1979 "old auid=%u new auid=%u" 1980 " old ses=%u new ses=%u", 1981 task->pid, task->uid, 1982 task->loginuid, loginuid, 1983 task->sessionid, sessionid); 1984 audit_log_end(ab); 1985 } 1986 } 1987 task->sessionid = sessionid; 1988 task->loginuid = loginuid; 1989 return 0; 1990 } 1991 1992 /** 1993 * __audit_mq_open - record audit data for a POSIX MQ open 1994 * @oflag: open flag 1995 * @mode: mode bits 1996 * @u_attr: queue attributes 1997 * 1998 * Returns 0 for success or NULL context or < 0 on error. 1999 */ 2000 int __audit_mq_open(int oflag, mode_t mode, struct mq_attr __user *u_attr) 2001 { 2002 struct audit_aux_data_mq_open *ax; 2003 struct audit_context *context = current->audit_context; 2004 2005 if (!audit_enabled) 2006 return 0; 2007 2008 if (likely(!context)) 2009 return 0; 2010 2011 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2012 if (!ax) 2013 return -ENOMEM; 2014 2015 if (u_attr != NULL) { 2016 if (copy_from_user(&ax->attr, u_attr, sizeof(ax->attr))) { 2017 kfree(ax); 2018 return -EFAULT; 2019 } 2020 } else 2021 memset(&ax->attr, 0, sizeof(ax->attr)); 2022 2023 ax->oflag = oflag; 2024 ax->mode = mode; 2025 2026 ax->d.type = AUDIT_MQ_OPEN; 2027 ax->d.next = context->aux; 2028 context->aux = (void *)ax; 2029 return 0; 2030 } 2031 2032 /** 2033 * __audit_mq_timedsend - record audit data for a POSIX MQ timed send 2034 * @mqdes: MQ descriptor 2035 * @msg_len: Message length 2036 * @msg_prio: Message priority 2037 * @u_abs_timeout: Message timeout in absolute time 2038 * 2039 * Returns 0 for success or NULL context or < 0 on error. 2040 */ 2041 int __audit_mq_timedsend(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, 2042 const struct timespec __user *u_abs_timeout) 2043 { 2044 struct audit_aux_data_mq_sendrecv *ax; 2045 struct audit_context *context = current->audit_context; 2046 2047 if (!audit_enabled) 2048 return 0; 2049 2050 if (likely(!context)) 2051 return 0; 2052 2053 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2054 if (!ax) 2055 return -ENOMEM; 2056 2057 if (u_abs_timeout != NULL) { 2058 if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) { 2059 kfree(ax); 2060 return -EFAULT; 2061 } 2062 } else 2063 memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout)); 2064 2065 ax->mqdes = mqdes; 2066 ax->msg_len = msg_len; 2067 ax->msg_prio = msg_prio; 2068 2069 ax->d.type = AUDIT_MQ_SENDRECV; 2070 ax->d.next = context->aux; 2071 context->aux = (void *)ax; 2072 return 0; 2073 } 2074 2075 /** 2076 * __audit_mq_timedreceive - record audit data for a POSIX MQ timed receive 2077 * @mqdes: MQ descriptor 2078 * @msg_len: Message length 2079 * @u_msg_prio: Message priority 2080 * @u_abs_timeout: Message timeout in absolute time 2081 * 2082 * Returns 0 for success or NULL context or < 0 on error. 2083 */ 2084 int __audit_mq_timedreceive(mqd_t mqdes, size_t msg_len, 2085 unsigned int __user *u_msg_prio, 2086 const struct timespec __user *u_abs_timeout) 2087 { 2088 struct audit_aux_data_mq_sendrecv *ax; 2089 struct audit_context *context = current->audit_context; 2090 2091 if (!audit_enabled) 2092 return 0; 2093 2094 if (likely(!context)) 2095 return 0; 2096 2097 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2098 if (!ax) 2099 return -ENOMEM; 2100 2101 if (u_msg_prio != NULL) { 2102 if (get_user(ax->msg_prio, u_msg_prio)) { 2103 kfree(ax); 2104 return -EFAULT; 2105 } 2106 } else 2107 ax->msg_prio = 0; 2108 2109 if (u_abs_timeout != NULL) { 2110 if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) { 2111 kfree(ax); 2112 return -EFAULT; 2113 } 2114 } else 2115 memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout)); 2116 2117 ax->mqdes = mqdes; 2118 ax->msg_len = msg_len; 2119 2120 ax->d.type = AUDIT_MQ_SENDRECV; 2121 ax->d.next = context->aux; 2122 context->aux = (void *)ax; 2123 return 0; 2124 } 2125 2126 /** 2127 * __audit_mq_notify - record audit data for a POSIX MQ notify 2128 * @mqdes: MQ descriptor 2129 * @u_notification: Notification event 2130 * 2131 * Returns 0 for success or NULL context or < 0 on error. 2132 */ 2133 2134 int __audit_mq_notify(mqd_t mqdes, const struct sigevent __user *u_notification) 2135 { 2136 struct audit_aux_data_mq_notify *ax; 2137 struct audit_context *context = current->audit_context; 2138 2139 if (!audit_enabled) 2140 return 0; 2141 2142 if (likely(!context)) 2143 return 0; 2144 2145 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2146 if (!ax) 2147 return -ENOMEM; 2148 2149 if (u_notification != NULL) { 2150 if (copy_from_user(&ax->notification, u_notification, sizeof(ax->notification))) { 2151 kfree(ax); 2152 return -EFAULT; 2153 } 2154 } else 2155 memset(&ax->notification, 0, sizeof(ax->notification)); 2156 2157 ax->mqdes = mqdes; 2158 2159 ax->d.type = AUDIT_MQ_NOTIFY; 2160 ax->d.next = context->aux; 2161 context->aux = (void *)ax; 2162 return 0; 2163 } 2164 2165 /** 2166 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute 2167 * @mqdes: MQ descriptor 2168 * @mqstat: MQ flags 2169 * 2170 * Returns 0 for success or NULL context or < 0 on error. 2171 */ 2172 int __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) 2173 { 2174 struct audit_aux_data_mq_getsetattr *ax; 2175 struct audit_context *context = current->audit_context; 2176 2177 if (!audit_enabled) 2178 return 0; 2179 2180 if (likely(!context)) 2181 return 0; 2182 2183 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2184 if (!ax) 2185 return -ENOMEM; 2186 2187 ax->mqdes = mqdes; 2188 ax->mqstat = *mqstat; 2189 2190 ax->d.type = AUDIT_MQ_GETSETATTR; 2191 ax->d.next = context->aux; 2192 context->aux = (void *)ax; 2193 return 0; 2194 } 2195 2196 /** 2197 * audit_ipc_obj - record audit data for ipc object 2198 * @ipcp: ipc permissions 2199 * 2200 * Returns 0 for success or NULL context or < 0 on error. 2201 */ 2202 int __audit_ipc_obj(struct kern_ipc_perm *ipcp) 2203 { 2204 struct audit_aux_data_ipcctl *ax; 2205 struct audit_context *context = current->audit_context; 2206 2207 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2208 if (!ax) 2209 return -ENOMEM; 2210 2211 ax->uid = ipcp->uid; 2212 ax->gid = ipcp->gid; 2213 ax->mode = ipcp->mode; 2214 security_ipc_getsecid(ipcp, &ax->osid); 2215 ax->d.type = AUDIT_IPC; 2216 ax->d.next = context->aux; 2217 context->aux = (void *)ax; 2218 return 0; 2219 } 2220 2221 /** 2222 * audit_ipc_set_perm - record audit data for new ipc permissions 2223 * @qbytes: msgq bytes 2224 * @uid: msgq user id 2225 * @gid: msgq group id 2226 * @mode: msgq mode (permissions) 2227 * 2228 * Returns 0 for success or NULL context or < 0 on error. 2229 */ 2230 int __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode) 2231 { 2232 struct audit_aux_data_ipcctl *ax; 2233 struct audit_context *context = current->audit_context; 2234 2235 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2236 if (!ax) 2237 return -ENOMEM; 2238 2239 ax->qbytes = qbytes; 2240 ax->uid = uid; 2241 ax->gid = gid; 2242 ax->mode = mode; 2243 2244 ax->d.type = AUDIT_IPC_SET_PERM; 2245 ax->d.next = context->aux; 2246 context->aux = (void *)ax; 2247 return 0; 2248 } 2249 2250 int audit_bprm(struct linux_binprm *bprm) 2251 { 2252 struct audit_aux_data_execve *ax; 2253 struct audit_context *context = current->audit_context; 2254 2255 if (likely(!audit_enabled || !context || context->dummy)) 2256 return 0; 2257 2258 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2259 if (!ax) 2260 return -ENOMEM; 2261 2262 ax->argc = bprm->argc; 2263 ax->envc = bprm->envc; 2264 ax->mm = bprm->mm; 2265 ax->d.type = AUDIT_EXECVE; 2266 ax->d.next = context->aux; 2267 context->aux = (void *)ax; 2268 return 0; 2269 } 2270 2271 2272 /** 2273 * audit_socketcall - record audit data for sys_socketcall 2274 * @nargs: number of args 2275 * @args: args array 2276 * 2277 * Returns 0 for success or NULL context or < 0 on error. 2278 */ 2279 int audit_socketcall(int nargs, unsigned long *args) 2280 { 2281 struct audit_aux_data_socketcall *ax; 2282 struct audit_context *context = current->audit_context; 2283 2284 if (likely(!context || context->dummy)) 2285 return 0; 2286 2287 ax = kmalloc(sizeof(*ax) + nargs * sizeof(unsigned long), GFP_KERNEL); 2288 if (!ax) 2289 return -ENOMEM; 2290 2291 ax->nargs = nargs; 2292 memcpy(ax->args, args, nargs * sizeof(unsigned long)); 2293 2294 ax->d.type = AUDIT_SOCKETCALL; 2295 ax->d.next = context->aux; 2296 context->aux = (void *)ax; 2297 return 0; 2298 } 2299 2300 /** 2301 * __audit_fd_pair - record audit data for pipe and socketpair 2302 * @fd1: the first file descriptor 2303 * @fd2: the second file descriptor 2304 * 2305 * Returns 0 for success or NULL context or < 0 on error. 2306 */ 2307 int __audit_fd_pair(int fd1, int fd2) 2308 { 2309 struct audit_context *context = current->audit_context; 2310 struct audit_aux_data_fd_pair *ax; 2311 2312 if (likely(!context)) { 2313 return 0; 2314 } 2315 2316 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2317 if (!ax) { 2318 return -ENOMEM; 2319 } 2320 2321 ax->fd[0] = fd1; 2322 ax->fd[1] = fd2; 2323 2324 ax->d.type = AUDIT_FD_PAIR; 2325 ax->d.next = context->aux; 2326 context->aux = (void *)ax; 2327 return 0; 2328 } 2329 2330 /** 2331 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto 2332 * @len: data length in user space 2333 * @a: data address in kernel space 2334 * 2335 * Returns 0 for success or NULL context or < 0 on error. 2336 */ 2337 int audit_sockaddr(int len, void *a) 2338 { 2339 struct audit_aux_data_sockaddr *ax; 2340 struct audit_context *context = current->audit_context; 2341 2342 if (likely(!context || context->dummy)) 2343 return 0; 2344 2345 ax = kmalloc(sizeof(*ax) + len, GFP_KERNEL); 2346 if (!ax) 2347 return -ENOMEM; 2348 2349 ax->len = len; 2350 memcpy(ax->a, a, len); 2351 2352 ax->d.type = AUDIT_SOCKADDR; 2353 ax->d.next = context->aux; 2354 context->aux = (void *)ax; 2355 return 0; 2356 } 2357 2358 void __audit_ptrace(struct task_struct *t) 2359 { 2360 struct audit_context *context = current->audit_context; 2361 2362 context->target_pid = t->pid; 2363 context->target_auid = audit_get_loginuid(t); 2364 context->target_uid = t->uid; 2365 context->target_sessionid = audit_get_sessionid(t); 2366 security_task_getsecid(t, &context->target_sid); 2367 memcpy(context->target_comm, t->comm, TASK_COMM_LEN); 2368 } 2369 2370 /** 2371 * audit_signal_info - record signal info for shutting down audit subsystem 2372 * @sig: signal value 2373 * @t: task being signaled 2374 * 2375 * If the audit subsystem is being terminated, record the task (pid) 2376 * and uid that is doing that. 2377 */ 2378 int __audit_signal_info(int sig, struct task_struct *t) 2379 { 2380 struct audit_aux_data_pids *axp; 2381 struct task_struct *tsk = current; 2382 struct audit_context *ctx = tsk->audit_context; 2383 2384 if (audit_pid && t->tgid == audit_pid) { 2385 if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) { 2386 audit_sig_pid = tsk->pid; 2387 if (tsk->loginuid != -1) 2388 audit_sig_uid = tsk->loginuid; 2389 else 2390 audit_sig_uid = tsk->uid; 2391 security_task_getsecid(tsk, &audit_sig_sid); 2392 } 2393 if (!audit_signals || audit_dummy_context()) 2394 return 0; 2395 } 2396 2397 /* optimize the common case by putting first signal recipient directly 2398 * in audit_context */ 2399 if (!ctx->target_pid) { 2400 ctx->target_pid = t->tgid; 2401 ctx->target_auid = audit_get_loginuid(t); 2402 ctx->target_uid = t->uid; 2403 ctx->target_sessionid = audit_get_sessionid(t); 2404 security_task_getsecid(t, &ctx->target_sid); 2405 memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); 2406 return 0; 2407 } 2408 2409 axp = (void *)ctx->aux_pids; 2410 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { 2411 axp = kzalloc(sizeof(*axp), GFP_ATOMIC); 2412 if (!axp) 2413 return -ENOMEM; 2414 2415 axp->d.type = AUDIT_OBJ_PID; 2416 axp->d.next = ctx->aux_pids; 2417 ctx->aux_pids = (void *)axp; 2418 } 2419 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); 2420 2421 axp->target_pid[axp->pid_count] = t->tgid; 2422 axp->target_auid[axp->pid_count] = audit_get_loginuid(t); 2423 axp->target_uid[axp->pid_count] = t->uid; 2424 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); 2425 security_task_getsecid(t, &axp->target_sid[axp->pid_count]); 2426 memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); 2427 axp->pid_count++; 2428 2429 return 0; 2430 } 2431 2432 /** 2433 * audit_core_dumps - record information about processes that end abnormally 2434 * @signr: signal value 2435 * 2436 * If a process ends with a core dump, something fishy is going on and we 2437 * should record the event for investigation. 2438 */ 2439 void audit_core_dumps(long signr) 2440 { 2441 struct audit_buffer *ab; 2442 u32 sid; 2443 uid_t auid = audit_get_loginuid(current); 2444 unsigned int sessionid = audit_get_sessionid(current); 2445 2446 if (!audit_enabled) 2447 return; 2448 2449 if (signr == SIGQUIT) /* don't care for those */ 2450 return; 2451 2452 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); 2453 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", 2454 auid, current->uid, current->gid, sessionid); 2455 security_task_getsecid(current, &sid); 2456 if (sid) { 2457 char *ctx = NULL; 2458 u32 len; 2459 2460 if (security_secid_to_secctx(sid, &ctx, &len)) 2461 audit_log_format(ab, " ssid=%u", sid); 2462 else { 2463 audit_log_format(ab, " subj=%s", ctx); 2464 security_release_secctx(ctx, len); 2465 } 2466 } 2467 audit_log_format(ab, " pid=%d comm=", current->pid); 2468 audit_log_untrustedstring(ab, current->comm); 2469 audit_log_format(ab, " sig=%ld", signr); 2470 audit_log_end(ab); 2471 } 2472