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