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 unsigned n; 247 if (unlikely(!ctx)) 248 return 0; 249 250 n = ctx->major; 251 switch (audit_classify_syscall(ctx->arch, n)) { 252 case 0: /* native */ 253 if ((mask & AUDIT_PERM_WRITE) && 254 audit_match_class(AUDIT_CLASS_WRITE, n)) 255 return 1; 256 if ((mask & AUDIT_PERM_READ) && 257 audit_match_class(AUDIT_CLASS_READ, n)) 258 return 1; 259 if ((mask & AUDIT_PERM_ATTR) && 260 audit_match_class(AUDIT_CLASS_CHATTR, n)) 261 return 1; 262 return 0; 263 case 1: /* 32bit on biarch */ 264 if ((mask & AUDIT_PERM_WRITE) && 265 audit_match_class(AUDIT_CLASS_WRITE_32, n)) 266 return 1; 267 if ((mask & AUDIT_PERM_READ) && 268 audit_match_class(AUDIT_CLASS_READ_32, n)) 269 return 1; 270 if ((mask & AUDIT_PERM_ATTR) && 271 audit_match_class(AUDIT_CLASS_CHATTR_32, n)) 272 return 1; 273 return 0; 274 case 2: /* open */ 275 return mask & ACC_MODE(ctx->argv[1]); 276 case 3: /* openat */ 277 return mask & ACC_MODE(ctx->argv[2]); 278 case 4: /* socketcall */ 279 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); 280 case 5: /* execve */ 281 return mask & AUDIT_PERM_EXEC; 282 default: 283 return 0; 284 } 285 } 286 287 static int audit_match_filetype(struct audit_context *ctx, int which) 288 { 289 unsigned index = which & ~S_IFMT; 290 mode_t mode = which & S_IFMT; 291 292 if (unlikely(!ctx)) 293 return 0; 294 295 if (index >= ctx->name_count) 296 return 0; 297 if (ctx->names[index].ino == -1) 298 return 0; 299 if ((ctx->names[index].mode ^ mode) & S_IFMT) 300 return 0; 301 return 1; 302 } 303 304 /* 305 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *; 306 * ->first_trees points to its beginning, ->trees - to the current end of data. 307 * ->tree_count is the number of free entries in array pointed to by ->trees. 308 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL, 309 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously, 310 * it's going to remain 1-element for almost any setup) until we free context itself. 311 * References in it _are_ dropped - at the same time we free/drop aux stuff. 312 */ 313 314 #ifdef CONFIG_AUDIT_TREE 315 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk) 316 { 317 struct audit_tree_refs *p = ctx->trees; 318 int left = ctx->tree_count; 319 if (likely(left)) { 320 p->c[--left] = chunk; 321 ctx->tree_count = left; 322 return 1; 323 } 324 if (!p) 325 return 0; 326 p = p->next; 327 if (p) { 328 p->c[30] = chunk; 329 ctx->trees = p; 330 ctx->tree_count = 30; 331 return 1; 332 } 333 return 0; 334 } 335 336 static int grow_tree_refs(struct audit_context *ctx) 337 { 338 struct audit_tree_refs *p = ctx->trees; 339 ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL); 340 if (!ctx->trees) { 341 ctx->trees = p; 342 return 0; 343 } 344 if (p) 345 p->next = ctx->trees; 346 else 347 ctx->first_trees = ctx->trees; 348 ctx->tree_count = 31; 349 return 1; 350 } 351 #endif 352 353 static void unroll_tree_refs(struct audit_context *ctx, 354 struct audit_tree_refs *p, int count) 355 { 356 #ifdef CONFIG_AUDIT_TREE 357 struct audit_tree_refs *q; 358 int n; 359 if (!p) { 360 /* we started with empty chain */ 361 p = ctx->first_trees; 362 count = 31; 363 /* if the very first allocation has failed, nothing to do */ 364 if (!p) 365 return; 366 } 367 n = count; 368 for (q = p; q != ctx->trees; q = q->next, n = 31) { 369 while (n--) { 370 audit_put_chunk(q->c[n]); 371 q->c[n] = NULL; 372 } 373 } 374 while (n-- > ctx->tree_count) { 375 audit_put_chunk(q->c[n]); 376 q->c[n] = NULL; 377 } 378 ctx->trees = p; 379 ctx->tree_count = count; 380 #endif 381 } 382 383 static void free_tree_refs(struct audit_context *ctx) 384 { 385 struct audit_tree_refs *p, *q; 386 for (p = ctx->first_trees; p; p = q) { 387 q = p->next; 388 kfree(p); 389 } 390 } 391 392 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree) 393 { 394 #ifdef CONFIG_AUDIT_TREE 395 struct audit_tree_refs *p; 396 int n; 397 if (!tree) 398 return 0; 399 /* full ones */ 400 for (p = ctx->first_trees; p != ctx->trees; p = p->next) { 401 for (n = 0; n < 31; n++) 402 if (audit_tree_match(p->c[n], tree)) 403 return 1; 404 } 405 /* partial */ 406 if (p) { 407 for (n = ctx->tree_count; n < 31; n++) 408 if (audit_tree_match(p->c[n], tree)) 409 return 1; 410 } 411 #endif 412 return 0; 413 } 414 415 /* Determine if any context name data matches a rule's watch data */ 416 /* Compare a task_struct with an audit_rule. Return 1 on match, 0 417 * otherwise. */ 418 static int audit_filter_rules(struct task_struct *tsk, 419 struct audit_krule *rule, 420 struct audit_context *ctx, 421 struct audit_names *name, 422 enum audit_state *state) 423 { 424 int i, j, need_sid = 1; 425 u32 sid; 426 427 for (i = 0; i < rule->field_count; i++) { 428 struct audit_field *f = &rule->fields[i]; 429 int result = 0; 430 431 switch (f->type) { 432 case AUDIT_PID: 433 result = audit_comparator(tsk->pid, f->op, f->val); 434 break; 435 case AUDIT_PPID: 436 if (ctx) { 437 if (!ctx->ppid) 438 ctx->ppid = sys_getppid(); 439 result = audit_comparator(ctx->ppid, f->op, f->val); 440 } 441 break; 442 case AUDIT_UID: 443 result = audit_comparator(tsk->uid, f->op, f->val); 444 break; 445 case AUDIT_EUID: 446 result = audit_comparator(tsk->euid, f->op, f->val); 447 break; 448 case AUDIT_SUID: 449 result = audit_comparator(tsk->suid, f->op, f->val); 450 break; 451 case AUDIT_FSUID: 452 result = audit_comparator(tsk->fsuid, f->op, f->val); 453 break; 454 case AUDIT_GID: 455 result = audit_comparator(tsk->gid, f->op, f->val); 456 break; 457 case AUDIT_EGID: 458 result = audit_comparator(tsk->egid, f->op, f->val); 459 break; 460 case AUDIT_SGID: 461 result = audit_comparator(tsk->sgid, f->op, f->val); 462 break; 463 case AUDIT_FSGID: 464 result = audit_comparator(tsk->fsgid, f->op, f->val); 465 break; 466 case AUDIT_PERS: 467 result = audit_comparator(tsk->personality, f->op, f->val); 468 break; 469 case AUDIT_ARCH: 470 if (ctx) 471 result = audit_comparator(ctx->arch, f->op, f->val); 472 break; 473 474 case AUDIT_EXIT: 475 if (ctx && ctx->return_valid) 476 result = audit_comparator(ctx->return_code, f->op, f->val); 477 break; 478 case AUDIT_SUCCESS: 479 if (ctx && ctx->return_valid) { 480 if (f->val) 481 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS); 482 else 483 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE); 484 } 485 break; 486 case AUDIT_DEVMAJOR: 487 if (name) 488 result = audit_comparator(MAJOR(name->dev), 489 f->op, f->val); 490 else if (ctx) { 491 for (j = 0; j < ctx->name_count; j++) { 492 if (audit_comparator(MAJOR(ctx->names[j].dev), f->op, f->val)) { 493 ++result; 494 break; 495 } 496 } 497 } 498 break; 499 case AUDIT_DEVMINOR: 500 if (name) 501 result = audit_comparator(MINOR(name->dev), 502 f->op, f->val); 503 else if (ctx) { 504 for (j = 0; j < ctx->name_count; j++) { 505 if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) { 506 ++result; 507 break; 508 } 509 } 510 } 511 break; 512 case AUDIT_INODE: 513 if (name) 514 result = (name->ino == f->val); 515 else if (ctx) { 516 for (j = 0; j < ctx->name_count; j++) { 517 if (audit_comparator(ctx->names[j].ino, f->op, f->val)) { 518 ++result; 519 break; 520 } 521 } 522 } 523 break; 524 case AUDIT_WATCH: 525 if (name && rule->watch->ino != (unsigned long)-1) 526 result = (name->dev == rule->watch->dev && 527 name->ino == rule->watch->ino); 528 break; 529 case AUDIT_DIR: 530 if (ctx) 531 result = match_tree_refs(ctx, rule->tree); 532 break; 533 case AUDIT_LOGINUID: 534 result = 0; 535 if (ctx) 536 result = audit_comparator(tsk->loginuid, f->op, f->val); 537 break; 538 case AUDIT_SUBJ_USER: 539 case AUDIT_SUBJ_ROLE: 540 case AUDIT_SUBJ_TYPE: 541 case AUDIT_SUBJ_SEN: 542 case AUDIT_SUBJ_CLR: 543 /* NOTE: this may return negative values indicating 544 a temporary error. We simply treat this as a 545 match for now to avoid losing information that 546 may be wanted. An error message will also be 547 logged upon error */ 548 if (f->lsm_rule) { 549 if (need_sid) { 550 security_task_getsecid(tsk, &sid); 551 need_sid = 0; 552 } 553 result = security_audit_rule_match(sid, f->type, 554 f->op, 555 f->lsm_rule, 556 ctx); 557 } 558 break; 559 case AUDIT_OBJ_USER: 560 case AUDIT_OBJ_ROLE: 561 case AUDIT_OBJ_TYPE: 562 case AUDIT_OBJ_LEV_LOW: 563 case AUDIT_OBJ_LEV_HIGH: 564 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR 565 also applies here */ 566 if (f->lsm_rule) { 567 /* Find files that match */ 568 if (name) { 569 result = security_audit_rule_match( 570 name->osid, f->type, f->op, 571 f->lsm_rule, ctx); 572 } else if (ctx) { 573 for (j = 0; j < ctx->name_count; j++) { 574 if (security_audit_rule_match( 575 ctx->names[j].osid, 576 f->type, f->op, 577 f->lsm_rule, ctx)) { 578 ++result; 579 break; 580 } 581 } 582 } 583 /* Find ipc objects that match */ 584 if (ctx) { 585 struct audit_aux_data *aux; 586 for (aux = ctx->aux; aux; 587 aux = aux->next) { 588 if (aux->type == AUDIT_IPC) { 589 struct audit_aux_data_ipcctl *axi = (void *)aux; 590 if (security_audit_rule_match(axi->osid, f->type, f->op, f->lsm_rule, ctx)) { 591 ++result; 592 break; 593 } 594 } 595 } 596 } 597 } 598 break; 599 case AUDIT_ARG0: 600 case AUDIT_ARG1: 601 case AUDIT_ARG2: 602 case AUDIT_ARG3: 603 if (ctx) 604 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val); 605 break; 606 case AUDIT_FILTERKEY: 607 /* ignore this field for filtering */ 608 result = 1; 609 break; 610 case AUDIT_PERM: 611 result = audit_match_perm(ctx, f->val); 612 break; 613 case AUDIT_FILETYPE: 614 result = audit_match_filetype(ctx, f->val); 615 break; 616 } 617 618 if (!result) 619 return 0; 620 } 621 if (rule->filterkey && ctx) 622 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC); 623 switch (rule->action) { 624 case AUDIT_NEVER: *state = AUDIT_DISABLED; break; 625 case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; 626 } 627 return 1; 628 } 629 630 /* At process creation time, we can determine if system-call auditing is 631 * completely disabled for this task. Since we only have the task 632 * structure at this point, we can only check uid and gid. 633 */ 634 static enum audit_state audit_filter_task(struct task_struct *tsk) 635 { 636 struct audit_entry *e; 637 enum audit_state state; 638 639 rcu_read_lock(); 640 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { 641 if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) { 642 rcu_read_unlock(); 643 return state; 644 } 645 } 646 rcu_read_unlock(); 647 return AUDIT_BUILD_CONTEXT; 648 } 649 650 /* At syscall entry and exit time, this filter is called if the 651 * audit_state is not low enough that auditing cannot take place, but is 652 * also not high enough that we already know we have to write an audit 653 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). 654 */ 655 static enum audit_state audit_filter_syscall(struct task_struct *tsk, 656 struct audit_context *ctx, 657 struct list_head *list) 658 { 659 struct audit_entry *e; 660 enum audit_state state; 661 662 if (audit_pid && tsk->tgid == audit_pid) 663 return AUDIT_DISABLED; 664 665 rcu_read_lock(); 666 if (!list_empty(list)) { 667 int word = AUDIT_WORD(ctx->major); 668 int bit = AUDIT_BIT(ctx->major); 669 670 list_for_each_entry_rcu(e, list, list) { 671 if ((e->rule.mask[word] & bit) == bit && 672 audit_filter_rules(tsk, &e->rule, ctx, NULL, 673 &state)) { 674 rcu_read_unlock(); 675 return state; 676 } 677 } 678 } 679 rcu_read_unlock(); 680 return AUDIT_BUILD_CONTEXT; 681 } 682 683 /* At syscall exit time, this filter is called if any audit_names[] have been 684 * collected during syscall processing. We only check rules in sublists at hash 685 * buckets applicable to the inode numbers in audit_names[]. 686 * Regarding audit_state, same rules apply as for audit_filter_syscall(). 687 */ 688 enum audit_state audit_filter_inodes(struct task_struct *tsk, 689 struct audit_context *ctx) 690 { 691 int i; 692 struct audit_entry *e; 693 enum audit_state state; 694 695 if (audit_pid && tsk->tgid == audit_pid) 696 return AUDIT_DISABLED; 697 698 rcu_read_lock(); 699 for (i = 0; i < ctx->name_count; i++) { 700 int word = AUDIT_WORD(ctx->major); 701 int bit = AUDIT_BIT(ctx->major); 702 struct audit_names *n = &ctx->names[i]; 703 int h = audit_hash_ino((u32)n->ino); 704 struct list_head *list = &audit_inode_hash[h]; 705 706 if (list_empty(list)) 707 continue; 708 709 list_for_each_entry_rcu(e, list, list) { 710 if ((e->rule.mask[word] & bit) == bit && 711 audit_filter_rules(tsk, &e->rule, ctx, n, &state)) { 712 rcu_read_unlock(); 713 return state; 714 } 715 } 716 } 717 rcu_read_unlock(); 718 return AUDIT_BUILD_CONTEXT; 719 } 720 721 void audit_set_auditable(struct audit_context *ctx) 722 { 723 ctx->auditable = 1; 724 } 725 726 static inline struct audit_context *audit_get_context(struct task_struct *tsk, 727 int return_valid, 728 int return_code) 729 { 730 struct audit_context *context = tsk->audit_context; 731 732 if (likely(!context)) 733 return NULL; 734 context->return_valid = return_valid; 735 736 /* 737 * we need to fix up the return code in the audit logs if the actual 738 * return codes are later going to be fixed up by the arch specific 739 * signal handlers 740 * 741 * This is actually a test for: 742 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) || 743 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK) 744 * 745 * but is faster than a bunch of || 746 */ 747 if (unlikely(return_code <= -ERESTARTSYS) && 748 (return_code >= -ERESTART_RESTARTBLOCK) && 749 (return_code != -ENOIOCTLCMD)) 750 context->return_code = -EINTR; 751 else 752 context->return_code = return_code; 753 754 if (context->in_syscall && !context->dummy && !context->auditable) { 755 enum audit_state state; 756 757 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]); 758 if (state == AUDIT_RECORD_CONTEXT) { 759 context->auditable = 1; 760 goto get_context; 761 } 762 763 state = audit_filter_inodes(tsk, context); 764 if (state == AUDIT_RECORD_CONTEXT) 765 context->auditable = 1; 766 767 } 768 769 get_context: 770 771 tsk->audit_context = NULL; 772 return context; 773 } 774 775 static inline void audit_free_names(struct audit_context *context) 776 { 777 int i; 778 779 #if AUDIT_DEBUG == 2 780 if (context->auditable 781 ||context->put_count + context->ino_count != context->name_count) { 782 printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d" 783 " name_count=%d put_count=%d" 784 " ino_count=%d [NOT freeing]\n", 785 __FILE__, __LINE__, 786 context->serial, context->major, context->in_syscall, 787 context->name_count, context->put_count, 788 context->ino_count); 789 for (i = 0; i < context->name_count; i++) { 790 printk(KERN_ERR "names[%d] = %p = %s\n", i, 791 context->names[i].name, 792 context->names[i].name ?: "(null)"); 793 } 794 dump_stack(); 795 return; 796 } 797 #endif 798 #if AUDIT_DEBUG 799 context->put_count = 0; 800 context->ino_count = 0; 801 #endif 802 803 for (i = 0; i < context->name_count; i++) { 804 if (context->names[i].name && context->names[i].name_put) 805 __putname(context->names[i].name); 806 } 807 context->name_count = 0; 808 path_put(&context->pwd); 809 context->pwd.dentry = NULL; 810 context->pwd.mnt = NULL; 811 } 812 813 static inline void audit_free_aux(struct audit_context *context) 814 { 815 struct audit_aux_data *aux; 816 817 while ((aux = context->aux)) { 818 context->aux = aux->next; 819 kfree(aux); 820 } 821 while ((aux = context->aux_pids)) { 822 context->aux_pids = aux->next; 823 kfree(aux); 824 } 825 } 826 827 static inline void audit_zero_context(struct audit_context *context, 828 enum audit_state state) 829 { 830 memset(context, 0, sizeof(*context)); 831 context->state = state; 832 } 833 834 static inline struct audit_context *audit_alloc_context(enum audit_state state) 835 { 836 struct audit_context *context; 837 838 if (!(context = kmalloc(sizeof(*context), GFP_KERNEL))) 839 return NULL; 840 audit_zero_context(context, state); 841 return context; 842 } 843 844 /** 845 * audit_alloc - allocate an audit context block for a task 846 * @tsk: task 847 * 848 * Filter on the task information and allocate a per-task audit context 849 * if necessary. Doing so turns on system call auditing for the 850 * specified task. This is called from copy_process, so no lock is 851 * needed. 852 */ 853 int audit_alloc(struct task_struct *tsk) 854 { 855 struct audit_context *context; 856 enum audit_state state; 857 858 if (likely(!audit_ever_enabled)) 859 return 0; /* Return if not auditing. */ 860 861 state = audit_filter_task(tsk); 862 if (likely(state == AUDIT_DISABLED)) 863 return 0; 864 865 if (!(context = audit_alloc_context(state))) { 866 audit_log_lost("out of memory in audit_alloc"); 867 return -ENOMEM; 868 } 869 870 tsk->audit_context = context; 871 set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); 872 return 0; 873 } 874 875 static inline void audit_free_context(struct audit_context *context) 876 { 877 struct audit_context *previous; 878 int count = 0; 879 880 do { 881 previous = context->previous; 882 if (previous || (count && count < 10)) { 883 ++count; 884 printk(KERN_ERR "audit(:%d): major=%d name_count=%d:" 885 " freeing multiple contexts (%d)\n", 886 context->serial, context->major, 887 context->name_count, count); 888 } 889 audit_free_names(context); 890 unroll_tree_refs(context, NULL, 0); 891 free_tree_refs(context); 892 audit_free_aux(context); 893 kfree(context->filterkey); 894 kfree(context); 895 context = previous; 896 } while (context); 897 if (count >= 10) 898 printk(KERN_ERR "audit: freed %d contexts\n", count); 899 } 900 901 void audit_log_task_context(struct audit_buffer *ab) 902 { 903 char *ctx = NULL; 904 unsigned len; 905 int error; 906 u32 sid; 907 908 security_task_getsecid(current, &sid); 909 if (!sid) 910 return; 911 912 error = security_secid_to_secctx(sid, &ctx, &len); 913 if (error) { 914 if (error != -EINVAL) 915 goto error_path; 916 return; 917 } 918 919 audit_log_format(ab, " subj=%s", ctx); 920 security_release_secctx(ctx, len); 921 return; 922 923 error_path: 924 audit_panic("error in audit_log_task_context"); 925 return; 926 } 927 928 EXPORT_SYMBOL(audit_log_task_context); 929 930 static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk) 931 { 932 char name[sizeof(tsk->comm)]; 933 struct mm_struct *mm = tsk->mm; 934 struct vm_area_struct *vma; 935 936 /* tsk == current */ 937 938 get_task_comm(name, tsk); 939 audit_log_format(ab, " comm="); 940 audit_log_untrustedstring(ab, name); 941 942 if (mm) { 943 down_read(&mm->mmap_sem); 944 vma = mm->mmap; 945 while (vma) { 946 if ((vma->vm_flags & VM_EXECUTABLE) && 947 vma->vm_file) { 948 audit_log_d_path(ab, "exe=", 949 &vma->vm_file->f_path); 950 break; 951 } 952 vma = vma->vm_next; 953 } 954 up_read(&mm->mmap_sem); 955 } 956 audit_log_task_context(ab); 957 } 958 959 static int audit_log_pid_context(struct audit_context *context, pid_t pid, 960 uid_t auid, uid_t uid, unsigned int sessionid, 961 u32 sid, char *comm) 962 { 963 struct audit_buffer *ab; 964 char *ctx = NULL; 965 u32 len; 966 int rc = 0; 967 968 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); 969 if (!ab) 970 return rc; 971 972 audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid, 973 uid, sessionid); 974 if (security_secid_to_secctx(sid, &ctx, &len)) { 975 audit_log_format(ab, " obj=(none)"); 976 rc = 1; 977 } else { 978 audit_log_format(ab, " obj=%s", ctx); 979 security_release_secctx(ctx, len); 980 } 981 audit_log_format(ab, " ocomm="); 982 audit_log_untrustedstring(ab, comm); 983 audit_log_end(ab); 984 985 return rc; 986 } 987 988 /* 989 * to_send and len_sent accounting are very loose estimates. We aren't 990 * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being 991 * within about 500 bytes (next page boundry) 992 * 993 * why snprintf? an int is up to 12 digits long. if we just assumed when 994 * logging that a[%d]= was going to be 16 characters long we would be wasting 995 * space in every audit message. In one 7500 byte message we can log up to 996 * about 1000 min size arguments. That comes down to about 50% waste of space 997 * if we didn't do the snprintf to find out how long arg_num_len was. 998 */ 999 static int audit_log_single_execve_arg(struct audit_context *context, 1000 struct audit_buffer **ab, 1001 int arg_num, 1002 size_t *len_sent, 1003 const char __user *p, 1004 char *buf) 1005 { 1006 char arg_num_len_buf[12]; 1007 const char __user *tmp_p = p; 1008 /* how many digits are in arg_num? 3 is the length of a=\n */ 1009 size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 3; 1010 size_t len, len_left, to_send; 1011 size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN; 1012 unsigned int i, has_cntl = 0, too_long = 0; 1013 int ret; 1014 1015 /* strnlen_user includes the null we don't want to send */ 1016 len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1; 1017 1018 /* 1019 * We just created this mm, if we can't find the strings 1020 * we just copied into it something is _very_ wrong. Similar 1021 * for strings that are too long, we should not have created 1022 * any. 1023 */ 1024 if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) { 1025 WARN_ON(1); 1026 send_sig(SIGKILL, current, 0); 1027 return -1; 1028 } 1029 1030 /* walk the whole argument looking for non-ascii chars */ 1031 do { 1032 if (len_left > MAX_EXECVE_AUDIT_LEN) 1033 to_send = MAX_EXECVE_AUDIT_LEN; 1034 else 1035 to_send = len_left; 1036 ret = copy_from_user(buf, tmp_p, to_send); 1037 /* 1038 * There is no reason for this copy to be short. We just 1039 * copied them here, and the mm hasn't been exposed to user- 1040 * space yet. 1041 */ 1042 if (ret) { 1043 WARN_ON(1); 1044 send_sig(SIGKILL, current, 0); 1045 return -1; 1046 } 1047 buf[to_send] = '\0'; 1048 has_cntl = audit_string_contains_control(buf, to_send); 1049 if (has_cntl) { 1050 /* 1051 * hex messages get logged as 2 bytes, so we can only 1052 * send half as much in each message 1053 */ 1054 max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2; 1055 break; 1056 } 1057 len_left -= to_send; 1058 tmp_p += to_send; 1059 } while (len_left > 0); 1060 1061 len_left = len; 1062 1063 if (len > max_execve_audit_len) 1064 too_long = 1; 1065 1066 /* rewalk the argument actually logging the message */ 1067 for (i = 0; len_left > 0; i++) { 1068 int room_left; 1069 1070 if (len_left > max_execve_audit_len) 1071 to_send = max_execve_audit_len; 1072 else 1073 to_send = len_left; 1074 1075 /* do we have space left to send this argument in this ab? */ 1076 room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent; 1077 if (has_cntl) 1078 room_left -= (to_send * 2); 1079 else 1080 room_left -= to_send; 1081 if (room_left < 0) { 1082 *len_sent = 0; 1083 audit_log_end(*ab); 1084 *ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE); 1085 if (!*ab) 1086 return 0; 1087 } 1088 1089 /* 1090 * first record needs to say how long the original string was 1091 * so we can be sure nothing was lost. 1092 */ 1093 if ((i == 0) && (too_long)) 1094 audit_log_format(*ab, "a%d_len=%zu ", arg_num, 1095 has_cntl ? 2*len : len); 1096 1097 /* 1098 * normally arguments are small enough to fit and we already 1099 * filled buf above when we checked for control characters 1100 * so don't bother with another copy_from_user 1101 */ 1102 if (len >= max_execve_audit_len) 1103 ret = copy_from_user(buf, p, to_send); 1104 else 1105 ret = 0; 1106 if (ret) { 1107 WARN_ON(1); 1108 send_sig(SIGKILL, current, 0); 1109 return -1; 1110 } 1111 buf[to_send] = '\0'; 1112 1113 /* actually log it */ 1114 audit_log_format(*ab, "a%d", arg_num); 1115 if (too_long) 1116 audit_log_format(*ab, "[%d]", i); 1117 audit_log_format(*ab, "="); 1118 if (has_cntl) 1119 audit_log_n_hex(*ab, buf, to_send); 1120 else 1121 audit_log_format(*ab, "\"%s\"", buf); 1122 audit_log_format(*ab, "\n"); 1123 1124 p += to_send; 1125 len_left -= to_send; 1126 *len_sent += arg_num_len; 1127 if (has_cntl) 1128 *len_sent += to_send * 2; 1129 else 1130 *len_sent += to_send; 1131 } 1132 /* include the null we didn't log */ 1133 return len + 1; 1134 } 1135 1136 static void audit_log_execve_info(struct audit_context *context, 1137 struct audit_buffer **ab, 1138 struct audit_aux_data_execve *axi) 1139 { 1140 int i; 1141 size_t len, len_sent = 0; 1142 const char __user *p; 1143 char *buf; 1144 1145 if (axi->mm != current->mm) 1146 return; /* execve failed, no additional info */ 1147 1148 p = (const char __user *)axi->mm->arg_start; 1149 1150 audit_log_format(*ab, "argc=%d ", axi->argc); 1151 1152 /* 1153 * we need some kernel buffer to hold the userspace args. Just 1154 * allocate one big one rather than allocating one of the right size 1155 * for every single argument inside audit_log_single_execve_arg() 1156 * should be <8k allocation so should be pretty safe. 1157 */ 1158 buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL); 1159 if (!buf) { 1160 audit_panic("out of memory for argv string\n"); 1161 return; 1162 } 1163 1164 for (i = 0; i < axi->argc; i++) { 1165 len = audit_log_single_execve_arg(context, ab, i, 1166 &len_sent, p, buf); 1167 if (len <= 0) 1168 break; 1169 p += len; 1170 } 1171 kfree(buf); 1172 } 1173 1174 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk) 1175 { 1176 int i, call_panic = 0; 1177 struct audit_buffer *ab; 1178 struct audit_aux_data *aux; 1179 const char *tty; 1180 1181 /* tsk == current */ 1182 context->pid = tsk->pid; 1183 if (!context->ppid) 1184 context->ppid = sys_getppid(); 1185 context->uid = tsk->uid; 1186 context->gid = tsk->gid; 1187 context->euid = tsk->euid; 1188 context->suid = tsk->suid; 1189 context->fsuid = tsk->fsuid; 1190 context->egid = tsk->egid; 1191 context->sgid = tsk->sgid; 1192 context->fsgid = tsk->fsgid; 1193 context->personality = tsk->personality; 1194 1195 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); 1196 if (!ab) 1197 return; /* audit_panic has been called */ 1198 audit_log_format(ab, "arch=%x syscall=%d", 1199 context->arch, context->major); 1200 if (context->personality != PER_LINUX) 1201 audit_log_format(ab, " per=%lx", context->personality); 1202 if (context->return_valid) 1203 audit_log_format(ab, " success=%s exit=%ld", 1204 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", 1205 context->return_code); 1206 1207 mutex_lock(&tty_mutex); 1208 read_lock(&tasklist_lock); 1209 if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name) 1210 tty = tsk->signal->tty->name; 1211 else 1212 tty = "(none)"; 1213 read_unlock(&tasklist_lock); 1214 audit_log_format(ab, 1215 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d" 1216 " ppid=%d pid=%d auid=%u uid=%u gid=%u" 1217 " euid=%u suid=%u fsuid=%u" 1218 " egid=%u sgid=%u fsgid=%u tty=%s ses=%u", 1219 context->argv[0], 1220 context->argv[1], 1221 context->argv[2], 1222 context->argv[3], 1223 context->name_count, 1224 context->ppid, 1225 context->pid, 1226 tsk->loginuid, 1227 context->uid, 1228 context->gid, 1229 context->euid, context->suid, context->fsuid, 1230 context->egid, context->sgid, context->fsgid, tty, 1231 tsk->sessionid); 1232 1233 mutex_unlock(&tty_mutex); 1234 1235 audit_log_task_info(ab, tsk); 1236 if (context->filterkey) { 1237 audit_log_format(ab, " key="); 1238 audit_log_untrustedstring(ab, context->filterkey); 1239 } else 1240 audit_log_format(ab, " key=(null)"); 1241 audit_log_end(ab); 1242 1243 for (aux = context->aux; aux; aux = aux->next) { 1244 1245 ab = audit_log_start(context, GFP_KERNEL, aux->type); 1246 if (!ab) 1247 continue; /* audit_panic has been called */ 1248 1249 switch (aux->type) { 1250 case AUDIT_MQ_OPEN: { 1251 struct audit_aux_data_mq_open *axi = (void *)aux; 1252 audit_log_format(ab, 1253 "oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld " 1254 "mq_msgsize=%ld mq_curmsgs=%ld", 1255 axi->oflag, axi->mode, axi->attr.mq_flags, 1256 axi->attr.mq_maxmsg, axi->attr.mq_msgsize, 1257 axi->attr.mq_curmsgs); 1258 break; } 1259 1260 case AUDIT_MQ_SENDRECV: { 1261 struct audit_aux_data_mq_sendrecv *axi = (void *)aux; 1262 audit_log_format(ab, 1263 "mqdes=%d msg_len=%zd msg_prio=%u " 1264 "abs_timeout_sec=%ld abs_timeout_nsec=%ld", 1265 axi->mqdes, axi->msg_len, axi->msg_prio, 1266 axi->abs_timeout.tv_sec, axi->abs_timeout.tv_nsec); 1267 break; } 1268 1269 case AUDIT_MQ_NOTIFY: { 1270 struct audit_aux_data_mq_notify *axi = (void *)aux; 1271 audit_log_format(ab, 1272 "mqdes=%d sigev_signo=%d", 1273 axi->mqdes, 1274 axi->notification.sigev_signo); 1275 break; } 1276 1277 case AUDIT_MQ_GETSETATTR: { 1278 struct audit_aux_data_mq_getsetattr *axi = (void *)aux; 1279 audit_log_format(ab, 1280 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld " 1281 "mq_curmsgs=%ld ", 1282 axi->mqdes, 1283 axi->mqstat.mq_flags, axi->mqstat.mq_maxmsg, 1284 axi->mqstat.mq_msgsize, axi->mqstat.mq_curmsgs); 1285 break; } 1286 1287 case AUDIT_IPC: { 1288 struct audit_aux_data_ipcctl *axi = (void *)aux; 1289 audit_log_format(ab, 1290 "ouid=%u ogid=%u mode=%#o", 1291 axi->uid, axi->gid, axi->mode); 1292 if (axi->osid != 0) { 1293 char *ctx = NULL; 1294 u32 len; 1295 if (security_secid_to_secctx( 1296 axi->osid, &ctx, &len)) { 1297 audit_log_format(ab, " osid=%u", 1298 axi->osid); 1299 call_panic = 1; 1300 } else { 1301 audit_log_format(ab, " obj=%s", ctx); 1302 security_release_secctx(ctx, len); 1303 } 1304 } 1305 break; } 1306 1307 case AUDIT_IPC_SET_PERM: { 1308 struct audit_aux_data_ipcctl *axi = (void *)aux; 1309 audit_log_format(ab, 1310 "qbytes=%lx ouid=%u ogid=%u mode=%#o", 1311 axi->qbytes, axi->uid, axi->gid, axi->mode); 1312 break; } 1313 1314 case AUDIT_EXECVE: { 1315 struct audit_aux_data_execve *axi = (void *)aux; 1316 audit_log_execve_info(context, &ab, axi); 1317 break; } 1318 1319 case AUDIT_SOCKETCALL: { 1320 struct audit_aux_data_socketcall *axs = (void *)aux; 1321 audit_log_format(ab, "nargs=%d", axs->nargs); 1322 for (i=0; i<axs->nargs; i++) 1323 audit_log_format(ab, " a%d=%lx", i, axs->args[i]); 1324 break; } 1325 1326 case AUDIT_SOCKADDR: { 1327 struct audit_aux_data_sockaddr *axs = (void *)aux; 1328 1329 audit_log_format(ab, "saddr="); 1330 audit_log_n_hex(ab, axs->a, axs->len); 1331 break; } 1332 1333 case AUDIT_FD_PAIR: { 1334 struct audit_aux_data_fd_pair *axs = (void *)aux; 1335 audit_log_format(ab, "fd0=%d fd1=%d", axs->fd[0], axs->fd[1]); 1336 break; } 1337 1338 } 1339 audit_log_end(ab); 1340 } 1341 1342 for (aux = context->aux_pids; aux; aux = aux->next) { 1343 struct audit_aux_data_pids *axs = (void *)aux; 1344 1345 for (i = 0; i < axs->pid_count; i++) 1346 if (audit_log_pid_context(context, axs->target_pid[i], 1347 axs->target_auid[i], 1348 axs->target_uid[i], 1349 axs->target_sessionid[i], 1350 axs->target_sid[i], 1351 axs->target_comm[i])) 1352 call_panic = 1; 1353 } 1354 1355 if (context->target_pid && 1356 audit_log_pid_context(context, context->target_pid, 1357 context->target_auid, context->target_uid, 1358 context->target_sessionid, 1359 context->target_sid, context->target_comm)) 1360 call_panic = 1; 1361 1362 if (context->pwd.dentry && context->pwd.mnt) { 1363 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); 1364 if (ab) { 1365 audit_log_d_path(ab, "cwd=", &context->pwd); 1366 audit_log_end(ab); 1367 } 1368 } 1369 for (i = 0; i < context->name_count; i++) { 1370 struct audit_names *n = &context->names[i]; 1371 1372 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH); 1373 if (!ab) 1374 continue; /* audit_panic has been called */ 1375 1376 audit_log_format(ab, "item=%d", i); 1377 1378 if (n->name) { 1379 switch(n->name_len) { 1380 case AUDIT_NAME_FULL: 1381 /* log the full path */ 1382 audit_log_format(ab, " name="); 1383 audit_log_untrustedstring(ab, n->name); 1384 break; 1385 case 0: 1386 /* name was specified as a relative path and the 1387 * directory component is the cwd */ 1388 audit_log_d_path(ab, " name=", &context->pwd); 1389 break; 1390 default: 1391 /* log the name's directory component */ 1392 audit_log_format(ab, " name="); 1393 audit_log_n_untrustedstring(ab, n->name, 1394 n->name_len); 1395 } 1396 } else 1397 audit_log_format(ab, " name=(null)"); 1398 1399 if (n->ino != (unsigned long)-1) { 1400 audit_log_format(ab, " inode=%lu" 1401 " dev=%02x:%02x mode=%#o" 1402 " ouid=%u ogid=%u rdev=%02x:%02x", 1403 n->ino, 1404 MAJOR(n->dev), 1405 MINOR(n->dev), 1406 n->mode, 1407 n->uid, 1408 n->gid, 1409 MAJOR(n->rdev), 1410 MINOR(n->rdev)); 1411 } 1412 if (n->osid != 0) { 1413 char *ctx = NULL; 1414 u32 len; 1415 if (security_secid_to_secctx( 1416 n->osid, &ctx, &len)) { 1417 audit_log_format(ab, " osid=%u", n->osid); 1418 call_panic = 2; 1419 } else { 1420 audit_log_format(ab, " obj=%s", ctx); 1421 security_release_secctx(ctx, len); 1422 } 1423 } 1424 1425 audit_log_end(ab); 1426 } 1427 1428 /* Send end of event record to help user space know we are finished */ 1429 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); 1430 if (ab) 1431 audit_log_end(ab); 1432 if (call_panic) 1433 audit_panic("error converting sid to string"); 1434 } 1435 1436 /** 1437 * audit_free - free a per-task audit context 1438 * @tsk: task whose audit context block to free 1439 * 1440 * Called from copy_process and do_exit 1441 */ 1442 void audit_free(struct task_struct *tsk) 1443 { 1444 struct audit_context *context; 1445 1446 context = audit_get_context(tsk, 0, 0); 1447 if (likely(!context)) 1448 return; 1449 1450 /* Check for system calls that do not go through the exit 1451 * function (e.g., exit_group), then free context block. 1452 * We use GFP_ATOMIC here because we might be doing this 1453 * in the context of the idle thread */ 1454 /* that can happen only if we are called from do_exit() */ 1455 if (context->in_syscall && context->auditable) 1456 audit_log_exit(context, tsk); 1457 1458 audit_free_context(context); 1459 } 1460 1461 /** 1462 * audit_syscall_entry - fill in an audit record at syscall entry 1463 * @tsk: task being audited 1464 * @arch: architecture type 1465 * @major: major syscall type (function) 1466 * @a1: additional syscall register 1 1467 * @a2: additional syscall register 2 1468 * @a3: additional syscall register 3 1469 * @a4: additional syscall register 4 1470 * 1471 * Fill in audit context at syscall entry. This only happens if the 1472 * audit context was created when the task was created and the state or 1473 * filters demand the audit context be built. If the state from the 1474 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, 1475 * then the record will be written at syscall exit time (otherwise, it 1476 * will only be written if another part of the kernel requests that it 1477 * be written). 1478 */ 1479 void audit_syscall_entry(int arch, int major, 1480 unsigned long a1, unsigned long a2, 1481 unsigned long a3, unsigned long a4) 1482 { 1483 struct task_struct *tsk = current; 1484 struct audit_context *context = tsk->audit_context; 1485 enum audit_state state; 1486 1487 if (unlikely(!context)) 1488 return; 1489 1490 /* 1491 * This happens only on certain architectures that make system 1492 * calls in kernel_thread via the entry.S interface, instead of 1493 * with direct calls. (If you are porting to a new 1494 * architecture, hitting this condition can indicate that you 1495 * got the _exit/_leave calls backward in entry.S.) 1496 * 1497 * i386 no 1498 * x86_64 no 1499 * ppc64 yes (see arch/powerpc/platforms/iseries/misc.S) 1500 * 1501 * This also happens with vm86 emulation in a non-nested manner 1502 * (entries without exits), so this case must be caught. 1503 */ 1504 if (context->in_syscall) { 1505 struct audit_context *newctx; 1506 1507 #if AUDIT_DEBUG 1508 printk(KERN_ERR 1509 "audit(:%d) pid=%d in syscall=%d;" 1510 " entering syscall=%d\n", 1511 context->serial, tsk->pid, context->major, major); 1512 #endif 1513 newctx = audit_alloc_context(context->state); 1514 if (newctx) { 1515 newctx->previous = context; 1516 context = newctx; 1517 tsk->audit_context = newctx; 1518 } else { 1519 /* If we can't alloc a new context, the best we 1520 * can do is to leak memory (any pending putname 1521 * will be lost). The only other alternative is 1522 * to abandon auditing. */ 1523 audit_zero_context(context, context->state); 1524 } 1525 } 1526 BUG_ON(context->in_syscall || context->name_count); 1527 1528 if (!audit_enabled) 1529 return; 1530 1531 context->arch = arch; 1532 context->major = major; 1533 context->argv[0] = a1; 1534 context->argv[1] = a2; 1535 context->argv[2] = a3; 1536 context->argv[3] = a4; 1537 1538 state = context->state; 1539 context->dummy = !audit_n_rules; 1540 if (!context->dummy && (state == AUDIT_SETUP_CONTEXT || state == AUDIT_BUILD_CONTEXT)) 1541 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]); 1542 if (likely(state == AUDIT_DISABLED)) 1543 return; 1544 1545 context->serial = 0; 1546 context->ctime = CURRENT_TIME; 1547 context->in_syscall = 1; 1548 context->auditable = !!(state == AUDIT_RECORD_CONTEXT); 1549 context->ppid = 0; 1550 } 1551 1552 /** 1553 * audit_syscall_exit - deallocate audit context after a system call 1554 * @tsk: task being audited 1555 * @valid: success/failure flag 1556 * @return_code: syscall return value 1557 * 1558 * Tear down after system call. If the audit context has been marked as 1559 * auditable (either because of the AUDIT_RECORD_CONTEXT state from 1560 * filtering, or because some other part of the kernel write an audit 1561 * message), then write out the syscall information. In call cases, 1562 * free the names stored from getname(). 1563 */ 1564 void audit_syscall_exit(int valid, long return_code) 1565 { 1566 struct task_struct *tsk = current; 1567 struct audit_context *context; 1568 1569 context = audit_get_context(tsk, valid, return_code); 1570 1571 if (likely(!context)) 1572 return; 1573 1574 if (context->in_syscall && context->auditable) 1575 audit_log_exit(context, tsk); 1576 1577 context->in_syscall = 0; 1578 context->auditable = 0; 1579 1580 if (context->previous) { 1581 struct audit_context *new_context = context->previous; 1582 context->previous = NULL; 1583 audit_free_context(context); 1584 tsk->audit_context = new_context; 1585 } else { 1586 audit_free_names(context); 1587 unroll_tree_refs(context, NULL, 0); 1588 audit_free_aux(context); 1589 context->aux = NULL; 1590 context->aux_pids = NULL; 1591 context->target_pid = 0; 1592 context->target_sid = 0; 1593 kfree(context->filterkey); 1594 context->filterkey = NULL; 1595 tsk->audit_context = context; 1596 } 1597 } 1598 1599 static inline void handle_one(const struct inode *inode) 1600 { 1601 #ifdef CONFIG_AUDIT_TREE 1602 struct audit_context *context; 1603 struct audit_tree_refs *p; 1604 struct audit_chunk *chunk; 1605 int count; 1606 if (likely(list_empty(&inode->inotify_watches))) 1607 return; 1608 context = current->audit_context; 1609 p = context->trees; 1610 count = context->tree_count; 1611 rcu_read_lock(); 1612 chunk = audit_tree_lookup(inode); 1613 rcu_read_unlock(); 1614 if (!chunk) 1615 return; 1616 if (likely(put_tree_ref(context, chunk))) 1617 return; 1618 if (unlikely(!grow_tree_refs(context))) { 1619 printk(KERN_WARNING "out of memory, audit has lost a tree reference\n"); 1620 audit_set_auditable(context); 1621 audit_put_chunk(chunk); 1622 unroll_tree_refs(context, p, count); 1623 return; 1624 } 1625 put_tree_ref(context, chunk); 1626 #endif 1627 } 1628 1629 static void handle_path(const struct dentry *dentry) 1630 { 1631 #ifdef CONFIG_AUDIT_TREE 1632 struct audit_context *context; 1633 struct audit_tree_refs *p; 1634 const struct dentry *d, *parent; 1635 struct audit_chunk *drop; 1636 unsigned long seq; 1637 int count; 1638 1639 context = current->audit_context; 1640 p = context->trees; 1641 count = context->tree_count; 1642 retry: 1643 drop = NULL; 1644 d = dentry; 1645 rcu_read_lock(); 1646 seq = read_seqbegin(&rename_lock); 1647 for(;;) { 1648 struct inode *inode = d->d_inode; 1649 if (inode && unlikely(!list_empty(&inode->inotify_watches))) { 1650 struct audit_chunk *chunk; 1651 chunk = audit_tree_lookup(inode); 1652 if (chunk) { 1653 if (unlikely(!put_tree_ref(context, chunk))) { 1654 drop = chunk; 1655 break; 1656 } 1657 } 1658 } 1659 parent = d->d_parent; 1660 if (parent == d) 1661 break; 1662 d = parent; 1663 } 1664 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */ 1665 rcu_read_unlock(); 1666 if (!drop) { 1667 /* just a race with rename */ 1668 unroll_tree_refs(context, p, count); 1669 goto retry; 1670 } 1671 audit_put_chunk(drop); 1672 if (grow_tree_refs(context)) { 1673 /* OK, got more space */ 1674 unroll_tree_refs(context, p, count); 1675 goto retry; 1676 } 1677 /* too bad */ 1678 printk(KERN_WARNING 1679 "out of memory, audit has lost a tree reference\n"); 1680 unroll_tree_refs(context, p, count); 1681 audit_set_auditable(context); 1682 return; 1683 } 1684 rcu_read_unlock(); 1685 #endif 1686 } 1687 1688 /** 1689 * audit_getname - add a name to the list 1690 * @name: name to add 1691 * 1692 * Add a name to the list of audit names for this context. 1693 * Called from fs/namei.c:getname(). 1694 */ 1695 void __audit_getname(const char *name) 1696 { 1697 struct audit_context *context = current->audit_context; 1698 1699 if (IS_ERR(name) || !name) 1700 return; 1701 1702 if (!context->in_syscall) { 1703 #if AUDIT_DEBUG == 2 1704 printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n", 1705 __FILE__, __LINE__, context->serial, name); 1706 dump_stack(); 1707 #endif 1708 return; 1709 } 1710 BUG_ON(context->name_count >= AUDIT_NAMES); 1711 context->names[context->name_count].name = name; 1712 context->names[context->name_count].name_len = AUDIT_NAME_FULL; 1713 context->names[context->name_count].name_put = 1; 1714 context->names[context->name_count].ino = (unsigned long)-1; 1715 context->names[context->name_count].osid = 0; 1716 ++context->name_count; 1717 if (!context->pwd.dentry) { 1718 read_lock(¤t->fs->lock); 1719 context->pwd = current->fs->pwd; 1720 path_get(¤t->fs->pwd); 1721 read_unlock(¤t->fs->lock); 1722 } 1723 1724 } 1725 1726 /* audit_putname - intercept a putname request 1727 * @name: name to intercept and delay for putname 1728 * 1729 * If we have stored the name from getname in the audit context, 1730 * then we delay the putname until syscall exit. 1731 * Called from include/linux/fs.h:putname(). 1732 */ 1733 void audit_putname(const char *name) 1734 { 1735 struct audit_context *context = current->audit_context; 1736 1737 BUG_ON(!context); 1738 if (!context->in_syscall) { 1739 #if AUDIT_DEBUG == 2 1740 printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n", 1741 __FILE__, __LINE__, context->serial, name); 1742 if (context->name_count) { 1743 int i; 1744 for (i = 0; i < context->name_count; i++) 1745 printk(KERN_ERR "name[%d] = %p = %s\n", i, 1746 context->names[i].name, 1747 context->names[i].name ?: "(null)"); 1748 } 1749 #endif 1750 __putname(name); 1751 } 1752 #if AUDIT_DEBUG 1753 else { 1754 ++context->put_count; 1755 if (context->put_count > context->name_count) { 1756 printk(KERN_ERR "%s:%d(:%d): major=%d" 1757 " in_syscall=%d putname(%p) name_count=%d" 1758 " put_count=%d\n", 1759 __FILE__, __LINE__, 1760 context->serial, context->major, 1761 context->in_syscall, name, context->name_count, 1762 context->put_count); 1763 dump_stack(); 1764 } 1765 } 1766 #endif 1767 } 1768 1769 static int audit_inc_name_count(struct audit_context *context, 1770 const struct inode *inode) 1771 { 1772 if (context->name_count >= AUDIT_NAMES) { 1773 if (inode) 1774 printk(KERN_DEBUG "name_count maxed, losing inode data: " 1775 "dev=%02x:%02x, inode=%lu\n", 1776 MAJOR(inode->i_sb->s_dev), 1777 MINOR(inode->i_sb->s_dev), 1778 inode->i_ino); 1779 1780 else 1781 printk(KERN_DEBUG "name_count maxed, losing inode data\n"); 1782 return 1; 1783 } 1784 context->name_count++; 1785 #if AUDIT_DEBUG 1786 context->ino_count++; 1787 #endif 1788 return 0; 1789 } 1790 1791 /* Copy inode data into an audit_names. */ 1792 static void audit_copy_inode(struct audit_names *name, const struct inode *inode) 1793 { 1794 name->ino = inode->i_ino; 1795 name->dev = inode->i_sb->s_dev; 1796 name->mode = inode->i_mode; 1797 name->uid = inode->i_uid; 1798 name->gid = inode->i_gid; 1799 name->rdev = inode->i_rdev; 1800 security_inode_getsecid(inode, &name->osid); 1801 } 1802 1803 /** 1804 * audit_inode - store the inode and device from a lookup 1805 * @name: name being audited 1806 * @dentry: dentry being audited 1807 * 1808 * Called from fs/namei.c:path_lookup(). 1809 */ 1810 void __audit_inode(const char *name, const struct dentry *dentry) 1811 { 1812 int idx; 1813 struct audit_context *context = current->audit_context; 1814 const struct inode *inode = dentry->d_inode; 1815 1816 if (!context->in_syscall) 1817 return; 1818 if (context->name_count 1819 && context->names[context->name_count-1].name 1820 && context->names[context->name_count-1].name == name) 1821 idx = context->name_count - 1; 1822 else if (context->name_count > 1 1823 && context->names[context->name_count-2].name 1824 && context->names[context->name_count-2].name == name) 1825 idx = context->name_count - 2; 1826 else { 1827 /* FIXME: how much do we care about inodes that have no 1828 * associated name? */ 1829 if (audit_inc_name_count(context, inode)) 1830 return; 1831 idx = context->name_count - 1; 1832 context->names[idx].name = NULL; 1833 } 1834 handle_path(dentry); 1835 audit_copy_inode(&context->names[idx], inode); 1836 } 1837 1838 /** 1839 * audit_inode_child - collect inode info for created/removed objects 1840 * @dname: inode's dentry name 1841 * @dentry: dentry being audited 1842 * @parent: inode of dentry parent 1843 * 1844 * For syscalls that create or remove filesystem objects, audit_inode 1845 * can only collect information for the filesystem object's parent. 1846 * This call updates the audit context with the child's information. 1847 * Syscalls that create a new filesystem object must be hooked after 1848 * the object is created. Syscalls that remove a filesystem object 1849 * must be hooked prior, in order to capture the target inode during 1850 * unsuccessful attempts. 1851 */ 1852 void __audit_inode_child(const char *dname, const struct dentry *dentry, 1853 const struct inode *parent) 1854 { 1855 int idx; 1856 struct audit_context *context = current->audit_context; 1857 const char *found_parent = NULL, *found_child = NULL; 1858 const struct inode *inode = dentry->d_inode; 1859 int dirlen = 0; 1860 1861 if (!context->in_syscall) 1862 return; 1863 1864 if (inode) 1865 handle_one(inode); 1866 /* determine matching parent */ 1867 if (!dname) 1868 goto add_names; 1869 1870 /* parent is more likely, look for it first */ 1871 for (idx = 0; idx < context->name_count; idx++) { 1872 struct audit_names *n = &context->names[idx]; 1873 1874 if (!n->name) 1875 continue; 1876 1877 if (n->ino == parent->i_ino && 1878 !audit_compare_dname_path(dname, n->name, &dirlen)) { 1879 n->name_len = dirlen; /* update parent data in place */ 1880 found_parent = n->name; 1881 goto add_names; 1882 } 1883 } 1884 1885 /* no matching parent, look for matching child */ 1886 for (idx = 0; idx < context->name_count; idx++) { 1887 struct audit_names *n = &context->names[idx]; 1888 1889 if (!n->name) 1890 continue; 1891 1892 /* strcmp() is the more likely scenario */ 1893 if (!strcmp(dname, n->name) || 1894 !audit_compare_dname_path(dname, n->name, &dirlen)) { 1895 if (inode) 1896 audit_copy_inode(n, inode); 1897 else 1898 n->ino = (unsigned long)-1; 1899 found_child = n->name; 1900 goto add_names; 1901 } 1902 } 1903 1904 add_names: 1905 if (!found_parent) { 1906 if (audit_inc_name_count(context, parent)) 1907 return; 1908 idx = context->name_count - 1; 1909 context->names[idx].name = NULL; 1910 audit_copy_inode(&context->names[idx], parent); 1911 } 1912 1913 if (!found_child) { 1914 if (audit_inc_name_count(context, inode)) 1915 return; 1916 idx = context->name_count - 1; 1917 1918 /* Re-use the name belonging to the slot for a matching parent 1919 * directory. All names for this context are relinquished in 1920 * audit_free_names() */ 1921 if (found_parent) { 1922 context->names[idx].name = found_parent; 1923 context->names[idx].name_len = AUDIT_NAME_FULL; 1924 /* don't call __putname() */ 1925 context->names[idx].name_put = 0; 1926 } else { 1927 context->names[idx].name = NULL; 1928 } 1929 1930 if (inode) 1931 audit_copy_inode(&context->names[idx], inode); 1932 else 1933 context->names[idx].ino = (unsigned long)-1; 1934 } 1935 } 1936 EXPORT_SYMBOL_GPL(__audit_inode_child); 1937 1938 /** 1939 * auditsc_get_stamp - get local copies of audit_context values 1940 * @ctx: audit_context for the task 1941 * @t: timespec to store time recorded in the audit_context 1942 * @serial: serial value that is recorded in the audit_context 1943 * 1944 * Also sets the context as auditable. 1945 */ 1946 void auditsc_get_stamp(struct audit_context *ctx, 1947 struct timespec *t, unsigned int *serial) 1948 { 1949 if (!ctx->serial) 1950 ctx->serial = audit_serial(); 1951 t->tv_sec = ctx->ctime.tv_sec; 1952 t->tv_nsec = ctx->ctime.tv_nsec; 1953 *serial = ctx->serial; 1954 ctx->auditable = 1; 1955 } 1956 1957 /* global counter which is incremented every time something logs in */ 1958 static atomic_t session_id = ATOMIC_INIT(0); 1959 1960 /** 1961 * audit_set_loginuid - set a task's audit_context loginuid 1962 * @task: task whose audit context is being modified 1963 * @loginuid: loginuid value 1964 * 1965 * Returns 0. 1966 * 1967 * Called (set) from fs/proc/base.c::proc_loginuid_write(). 1968 */ 1969 int audit_set_loginuid(struct task_struct *task, uid_t loginuid) 1970 { 1971 unsigned int sessionid = atomic_inc_return(&session_id); 1972 struct audit_context *context = task->audit_context; 1973 1974 if (context && context->in_syscall) { 1975 struct audit_buffer *ab; 1976 1977 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); 1978 if (ab) { 1979 audit_log_format(ab, "login pid=%d uid=%u " 1980 "old auid=%u new auid=%u" 1981 " old ses=%u new ses=%u", 1982 task->pid, task->uid, 1983 task->loginuid, loginuid, 1984 task->sessionid, sessionid); 1985 audit_log_end(ab); 1986 } 1987 } 1988 task->sessionid = sessionid; 1989 task->loginuid = loginuid; 1990 return 0; 1991 } 1992 1993 /** 1994 * __audit_mq_open - record audit data for a POSIX MQ open 1995 * @oflag: open flag 1996 * @mode: mode bits 1997 * @u_attr: queue attributes 1998 * 1999 * Returns 0 for success or NULL context or < 0 on error. 2000 */ 2001 int __audit_mq_open(int oflag, mode_t mode, struct mq_attr __user *u_attr) 2002 { 2003 struct audit_aux_data_mq_open *ax; 2004 struct audit_context *context = current->audit_context; 2005 2006 if (!audit_enabled) 2007 return 0; 2008 2009 if (likely(!context)) 2010 return 0; 2011 2012 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2013 if (!ax) 2014 return -ENOMEM; 2015 2016 if (u_attr != NULL) { 2017 if (copy_from_user(&ax->attr, u_attr, sizeof(ax->attr))) { 2018 kfree(ax); 2019 return -EFAULT; 2020 } 2021 } else 2022 memset(&ax->attr, 0, sizeof(ax->attr)); 2023 2024 ax->oflag = oflag; 2025 ax->mode = mode; 2026 2027 ax->d.type = AUDIT_MQ_OPEN; 2028 ax->d.next = context->aux; 2029 context->aux = (void *)ax; 2030 return 0; 2031 } 2032 2033 /** 2034 * __audit_mq_timedsend - record audit data for a POSIX MQ timed send 2035 * @mqdes: MQ descriptor 2036 * @msg_len: Message length 2037 * @msg_prio: Message priority 2038 * @u_abs_timeout: Message timeout in absolute time 2039 * 2040 * Returns 0 for success or NULL context or < 0 on error. 2041 */ 2042 int __audit_mq_timedsend(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, 2043 const struct timespec __user *u_abs_timeout) 2044 { 2045 struct audit_aux_data_mq_sendrecv *ax; 2046 struct audit_context *context = current->audit_context; 2047 2048 if (!audit_enabled) 2049 return 0; 2050 2051 if (likely(!context)) 2052 return 0; 2053 2054 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2055 if (!ax) 2056 return -ENOMEM; 2057 2058 if (u_abs_timeout != NULL) { 2059 if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) { 2060 kfree(ax); 2061 return -EFAULT; 2062 } 2063 } else 2064 memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout)); 2065 2066 ax->mqdes = mqdes; 2067 ax->msg_len = msg_len; 2068 ax->msg_prio = msg_prio; 2069 2070 ax->d.type = AUDIT_MQ_SENDRECV; 2071 ax->d.next = context->aux; 2072 context->aux = (void *)ax; 2073 return 0; 2074 } 2075 2076 /** 2077 * __audit_mq_timedreceive - record audit data for a POSIX MQ timed receive 2078 * @mqdes: MQ descriptor 2079 * @msg_len: Message length 2080 * @u_msg_prio: Message priority 2081 * @u_abs_timeout: Message timeout in absolute time 2082 * 2083 * Returns 0 for success or NULL context or < 0 on error. 2084 */ 2085 int __audit_mq_timedreceive(mqd_t mqdes, size_t msg_len, 2086 unsigned int __user *u_msg_prio, 2087 const struct timespec __user *u_abs_timeout) 2088 { 2089 struct audit_aux_data_mq_sendrecv *ax; 2090 struct audit_context *context = current->audit_context; 2091 2092 if (!audit_enabled) 2093 return 0; 2094 2095 if (likely(!context)) 2096 return 0; 2097 2098 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2099 if (!ax) 2100 return -ENOMEM; 2101 2102 if (u_msg_prio != NULL) { 2103 if (get_user(ax->msg_prio, u_msg_prio)) { 2104 kfree(ax); 2105 return -EFAULT; 2106 } 2107 } else 2108 ax->msg_prio = 0; 2109 2110 if (u_abs_timeout != NULL) { 2111 if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) { 2112 kfree(ax); 2113 return -EFAULT; 2114 } 2115 } else 2116 memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout)); 2117 2118 ax->mqdes = mqdes; 2119 ax->msg_len = msg_len; 2120 2121 ax->d.type = AUDIT_MQ_SENDRECV; 2122 ax->d.next = context->aux; 2123 context->aux = (void *)ax; 2124 return 0; 2125 } 2126 2127 /** 2128 * __audit_mq_notify - record audit data for a POSIX MQ notify 2129 * @mqdes: MQ descriptor 2130 * @u_notification: Notification event 2131 * 2132 * Returns 0 for success or NULL context or < 0 on error. 2133 */ 2134 2135 int __audit_mq_notify(mqd_t mqdes, const struct sigevent __user *u_notification) 2136 { 2137 struct audit_aux_data_mq_notify *ax; 2138 struct audit_context *context = current->audit_context; 2139 2140 if (!audit_enabled) 2141 return 0; 2142 2143 if (likely(!context)) 2144 return 0; 2145 2146 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2147 if (!ax) 2148 return -ENOMEM; 2149 2150 if (u_notification != NULL) { 2151 if (copy_from_user(&ax->notification, u_notification, sizeof(ax->notification))) { 2152 kfree(ax); 2153 return -EFAULT; 2154 } 2155 } else 2156 memset(&ax->notification, 0, sizeof(ax->notification)); 2157 2158 ax->mqdes = mqdes; 2159 2160 ax->d.type = AUDIT_MQ_NOTIFY; 2161 ax->d.next = context->aux; 2162 context->aux = (void *)ax; 2163 return 0; 2164 } 2165 2166 /** 2167 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute 2168 * @mqdes: MQ descriptor 2169 * @mqstat: MQ flags 2170 * 2171 * Returns 0 for success or NULL context or < 0 on error. 2172 */ 2173 int __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) 2174 { 2175 struct audit_aux_data_mq_getsetattr *ax; 2176 struct audit_context *context = current->audit_context; 2177 2178 if (!audit_enabled) 2179 return 0; 2180 2181 if (likely(!context)) 2182 return 0; 2183 2184 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2185 if (!ax) 2186 return -ENOMEM; 2187 2188 ax->mqdes = mqdes; 2189 ax->mqstat = *mqstat; 2190 2191 ax->d.type = AUDIT_MQ_GETSETATTR; 2192 ax->d.next = context->aux; 2193 context->aux = (void *)ax; 2194 return 0; 2195 } 2196 2197 /** 2198 * audit_ipc_obj - record audit data for ipc object 2199 * @ipcp: ipc permissions 2200 * 2201 * Returns 0 for success or NULL context or < 0 on error. 2202 */ 2203 int __audit_ipc_obj(struct kern_ipc_perm *ipcp) 2204 { 2205 struct audit_aux_data_ipcctl *ax; 2206 struct audit_context *context = current->audit_context; 2207 2208 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2209 if (!ax) 2210 return -ENOMEM; 2211 2212 ax->uid = ipcp->uid; 2213 ax->gid = ipcp->gid; 2214 ax->mode = ipcp->mode; 2215 security_ipc_getsecid(ipcp, &ax->osid); 2216 ax->d.type = AUDIT_IPC; 2217 ax->d.next = context->aux; 2218 context->aux = (void *)ax; 2219 return 0; 2220 } 2221 2222 /** 2223 * audit_ipc_set_perm - record audit data for new ipc permissions 2224 * @qbytes: msgq bytes 2225 * @uid: msgq user id 2226 * @gid: msgq group id 2227 * @mode: msgq mode (permissions) 2228 * 2229 * Returns 0 for success or NULL context or < 0 on error. 2230 */ 2231 int __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode) 2232 { 2233 struct audit_aux_data_ipcctl *ax; 2234 struct audit_context *context = current->audit_context; 2235 2236 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 2237 if (!ax) 2238 return -ENOMEM; 2239 2240 ax->qbytes = qbytes; 2241 ax->uid = uid; 2242 ax->gid = gid; 2243 ax->mode = mode; 2244 2245 ax->d.type = AUDIT_IPC_SET_PERM; 2246 ax->d.next = context->aux; 2247 context->aux = (void *)ax; 2248 return 0; 2249 } 2250 2251 int audit_bprm(struct linux_binprm *bprm) 2252 { 2253 struct audit_aux_data_execve *ax; 2254 struct audit_context *context = current->audit_context; 2255 2256 if (likely(!audit_enabled || !context || context->dummy)) 2257 return 0; 2258 2259 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2260 if (!ax) 2261 return -ENOMEM; 2262 2263 ax->argc = bprm->argc; 2264 ax->envc = bprm->envc; 2265 ax->mm = bprm->mm; 2266 ax->d.type = AUDIT_EXECVE; 2267 ax->d.next = context->aux; 2268 context->aux = (void *)ax; 2269 return 0; 2270 } 2271 2272 2273 /** 2274 * audit_socketcall - record audit data for sys_socketcall 2275 * @nargs: number of args 2276 * @args: args array 2277 * 2278 * Returns 0 for success or NULL context or < 0 on error. 2279 */ 2280 int audit_socketcall(int nargs, unsigned long *args) 2281 { 2282 struct audit_aux_data_socketcall *ax; 2283 struct audit_context *context = current->audit_context; 2284 2285 if (likely(!context || context->dummy)) 2286 return 0; 2287 2288 ax = kmalloc(sizeof(*ax) + nargs * sizeof(unsigned long), GFP_KERNEL); 2289 if (!ax) 2290 return -ENOMEM; 2291 2292 ax->nargs = nargs; 2293 memcpy(ax->args, args, nargs * sizeof(unsigned long)); 2294 2295 ax->d.type = AUDIT_SOCKETCALL; 2296 ax->d.next = context->aux; 2297 context->aux = (void *)ax; 2298 return 0; 2299 } 2300 2301 /** 2302 * __audit_fd_pair - record audit data for pipe and socketpair 2303 * @fd1: the first file descriptor 2304 * @fd2: the second file descriptor 2305 * 2306 * Returns 0 for success or NULL context or < 0 on error. 2307 */ 2308 int __audit_fd_pair(int fd1, int fd2) 2309 { 2310 struct audit_context *context = current->audit_context; 2311 struct audit_aux_data_fd_pair *ax; 2312 2313 if (likely(!context)) { 2314 return 0; 2315 } 2316 2317 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2318 if (!ax) { 2319 return -ENOMEM; 2320 } 2321 2322 ax->fd[0] = fd1; 2323 ax->fd[1] = fd2; 2324 2325 ax->d.type = AUDIT_FD_PAIR; 2326 ax->d.next = context->aux; 2327 context->aux = (void *)ax; 2328 return 0; 2329 } 2330 2331 /** 2332 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto 2333 * @len: data length in user space 2334 * @a: data address in kernel space 2335 * 2336 * Returns 0 for success or NULL context or < 0 on error. 2337 */ 2338 int audit_sockaddr(int len, void *a) 2339 { 2340 struct audit_aux_data_sockaddr *ax; 2341 struct audit_context *context = current->audit_context; 2342 2343 if (likely(!context || context->dummy)) 2344 return 0; 2345 2346 ax = kmalloc(sizeof(*ax) + len, GFP_KERNEL); 2347 if (!ax) 2348 return -ENOMEM; 2349 2350 ax->len = len; 2351 memcpy(ax->a, a, len); 2352 2353 ax->d.type = AUDIT_SOCKADDR; 2354 ax->d.next = context->aux; 2355 context->aux = (void *)ax; 2356 return 0; 2357 } 2358 2359 void __audit_ptrace(struct task_struct *t) 2360 { 2361 struct audit_context *context = current->audit_context; 2362 2363 context->target_pid = t->pid; 2364 context->target_auid = audit_get_loginuid(t); 2365 context->target_uid = t->uid; 2366 context->target_sessionid = audit_get_sessionid(t); 2367 security_task_getsecid(t, &context->target_sid); 2368 memcpy(context->target_comm, t->comm, TASK_COMM_LEN); 2369 } 2370 2371 /** 2372 * audit_signal_info - record signal info for shutting down audit subsystem 2373 * @sig: signal value 2374 * @t: task being signaled 2375 * 2376 * If the audit subsystem is being terminated, record the task (pid) 2377 * and uid that is doing that. 2378 */ 2379 int __audit_signal_info(int sig, struct task_struct *t) 2380 { 2381 struct audit_aux_data_pids *axp; 2382 struct task_struct *tsk = current; 2383 struct audit_context *ctx = tsk->audit_context; 2384 2385 if (audit_pid && t->tgid == audit_pid) { 2386 if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) { 2387 audit_sig_pid = tsk->pid; 2388 if (tsk->loginuid != -1) 2389 audit_sig_uid = tsk->loginuid; 2390 else 2391 audit_sig_uid = tsk->uid; 2392 security_task_getsecid(tsk, &audit_sig_sid); 2393 } 2394 if (!audit_signals || audit_dummy_context()) 2395 return 0; 2396 } 2397 2398 /* optimize the common case by putting first signal recipient directly 2399 * in audit_context */ 2400 if (!ctx->target_pid) { 2401 ctx->target_pid = t->tgid; 2402 ctx->target_auid = audit_get_loginuid(t); 2403 ctx->target_uid = t->uid; 2404 ctx->target_sessionid = audit_get_sessionid(t); 2405 security_task_getsecid(t, &ctx->target_sid); 2406 memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); 2407 return 0; 2408 } 2409 2410 axp = (void *)ctx->aux_pids; 2411 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { 2412 axp = kzalloc(sizeof(*axp), GFP_ATOMIC); 2413 if (!axp) 2414 return -ENOMEM; 2415 2416 axp->d.type = AUDIT_OBJ_PID; 2417 axp->d.next = ctx->aux_pids; 2418 ctx->aux_pids = (void *)axp; 2419 } 2420 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); 2421 2422 axp->target_pid[axp->pid_count] = t->tgid; 2423 axp->target_auid[axp->pid_count] = audit_get_loginuid(t); 2424 axp->target_uid[axp->pid_count] = t->uid; 2425 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); 2426 security_task_getsecid(t, &axp->target_sid[axp->pid_count]); 2427 memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); 2428 axp->pid_count++; 2429 2430 return 0; 2431 } 2432 2433 /** 2434 * audit_core_dumps - record information about processes that end abnormally 2435 * @signr: signal value 2436 * 2437 * If a process ends with a core dump, something fishy is going on and we 2438 * should record the event for investigation. 2439 */ 2440 void audit_core_dumps(long signr) 2441 { 2442 struct audit_buffer *ab; 2443 u32 sid; 2444 uid_t auid = audit_get_loginuid(current); 2445 unsigned int sessionid = audit_get_sessionid(current); 2446 2447 if (!audit_enabled) 2448 return; 2449 2450 if (signr == SIGQUIT) /* don't care for those */ 2451 return; 2452 2453 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); 2454 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", 2455 auid, current->uid, current->gid, sessionid); 2456 security_task_getsecid(current, &sid); 2457 if (sid) { 2458 char *ctx = NULL; 2459 u32 len; 2460 2461 if (security_secid_to_secctx(sid, &ctx, &len)) 2462 audit_log_format(ab, " ssid=%u", sid); 2463 else { 2464 audit_log_format(ab, " subj=%s", ctx); 2465 security_release_secctx(ctx, len); 2466 } 2467 } 2468 audit_log_format(ab, " pid=%d comm=", current->pid); 2469 audit_log_untrustedstring(ab, current->comm); 2470 audit_log_format(ab, " sig=%ld", signr); 2471 audit_log_end(ab); 2472 } 2473