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 <linux/atomic.h> 48 #include <linux/fs.h> 49 #include <linux/namei.h> 50 #include <linux/mm.h> 51 #include <linux/export.h> 52 #include <linux/slab.h> 53 #include <linux/mount.h> 54 #include <linux/socket.h> 55 #include <linux/mqueue.h> 56 #include <linux/audit.h> 57 #include <linux/personality.h> 58 #include <linux/time.h> 59 #include <linux/netlink.h> 60 #include <linux/compiler.h> 61 #include <asm/unistd.h> 62 #include <linux/security.h> 63 #include <linux/list.h> 64 #include <linux/tty.h> 65 #include <linux/binfmts.h> 66 #include <linux/highmem.h> 67 #include <linux/syscalls.h> 68 #include <linux/capability.h> 69 #include <linux/fs_struct.h> 70 71 #include "audit.h" 72 73 /* flags stating the success for a syscall */ 74 #define AUDITSC_INVALID 0 75 #define AUDITSC_SUCCESS 1 76 #define AUDITSC_FAILURE 2 77 78 /* AUDIT_NAMES is the number of slots we reserve in the audit_context 79 * for saving names from getname(). If we get more names we will allocate 80 * a name dynamically and also add those to the list anchored by names_list. */ 81 #define AUDIT_NAMES 5 82 83 /* Indicates that audit should log the full pathname. */ 84 #define AUDIT_NAME_FULL -1 85 86 /* no execve audit message should be longer than this (userspace limits) */ 87 #define MAX_EXECVE_AUDIT_LEN 7500 88 89 /* number of audit rules */ 90 int audit_n_rules; 91 92 /* determines whether we collect data for signals sent */ 93 int audit_signals; 94 95 struct audit_cap_data { 96 kernel_cap_t permitted; 97 kernel_cap_t inheritable; 98 union { 99 unsigned int fE; /* effective bit of a file capability */ 100 kernel_cap_t effective; /* effective set of a process */ 101 }; 102 }; 103 104 /* When fs/namei.c:getname() is called, we store the pointer in name and 105 * we don't let putname() free it (instead we free all of the saved 106 * pointers at syscall exit time). 107 * 108 * Further, in fs/namei.c:path_lookup() we store the inode and device. */ 109 struct audit_names { 110 struct list_head list; /* audit_context->names_list */ 111 const char *name; 112 unsigned long ino; 113 dev_t dev; 114 umode_t mode; 115 uid_t uid; 116 gid_t gid; 117 dev_t rdev; 118 u32 osid; 119 struct audit_cap_data fcap; 120 unsigned int fcap_ver; 121 int name_len; /* number of name's characters to log */ 122 bool name_put; /* call __putname() for this name */ 123 /* 124 * This was an allocated audit_names and not from the array of 125 * names allocated in the task audit context. Thus this name 126 * should be freed on syscall exit 127 */ 128 bool should_free; 129 }; 130 131 struct audit_aux_data { 132 struct audit_aux_data *next; 133 int type; 134 }; 135 136 #define AUDIT_AUX_IPCPERM 0 137 138 /* Number of target pids per aux struct. */ 139 #define AUDIT_AUX_PIDS 16 140 141 struct audit_aux_data_execve { 142 struct audit_aux_data d; 143 int argc; 144 int envc; 145 struct mm_struct *mm; 146 }; 147 148 struct audit_aux_data_pids { 149 struct audit_aux_data d; 150 pid_t target_pid[AUDIT_AUX_PIDS]; 151 uid_t target_auid[AUDIT_AUX_PIDS]; 152 uid_t target_uid[AUDIT_AUX_PIDS]; 153 unsigned int target_sessionid[AUDIT_AUX_PIDS]; 154 u32 target_sid[AUDIT_AUX_PIDS]; 155 char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN]; 156 int pid_count; 157 }; 158 159 struct audit_aux_data_bprm_fcaps { 160 struct audit_aux_data d; 161 struct audit_cap_data fcap; 162 unsigned int fcap_ver; 163 struct audit_cap_data old_pcap; 164 struct audit_cap_data new_pcap; 165 }; 166 167 struct audit_aux_data_capset { 168 struct audit_aux_data d; 169 pid_t pid; 170 struct audit_cap_data cap; 171 }; 172 173 struct audit_tree_refs { 174 struct audit_tree_refs *next; 175 struct audit_chunk *c[31]; 176 }; 177 178 /* The per-task audit context. */ 179 struct audit_context { 180 int dummy; /* must be the first element */ 181 int in_syscall; /* 1 if task is in a syscall */ 182 enum audit_state state, current_state; 183 unsigned int serial; /* serial number for record */ 184 int major; /* syscall number */ 185 struct timespec ctime; /* time of syscall entry */ 186 unsigned long argv[4]; /* syscall arguments */ 187 long return_code;/* syscall return code */ 188 u64 prio; 189 int return_valid; /* return code is valid */ 190 /* 191 * The names_list is the list of all audit_names collected during this 192 * syscall. The first AUDIT_NAMES entries in the names_list will 193 * actually be from the preallocated_names array for performance 194 * reasons. Except during allocation they should never be referenced 195 * through the preallocated_names array and should only be found/used 196 * by running the names_list. 197 */ 198 struct audit_names preallocated_names[AUDIT_NAMES]; 199 int name_count; /* total records in names_list */ 200 struct list_head names_list; /* anchor for struct audit_names->list */ 201 char * filterkey; /* key for rule that triggered record */ 202 struct path pwd; 203 struct audit_context *previous; /* For nested syscalls */ 204 struct audit_aux_data *aux; 205 struct audit_aux_data *aux_pids; 206 struct sockaddr_storage *sockaddr; 207 size_t sockaddr_len; 208 /* Save things to print about task_struct */ 209 pid_t pid, ppid; 210 uid_t uid, euid, suid, fsuid; 211 gid_t gid, egid, sgid, fsgid; 212 unsigned long personality; 213 int arch; 214 215 pid_t target_pid; 216 uid_t target_auid; 217 uid_t target_uid; 218 unsigned int target_sessionid; 219 u32 target_sid; 220 char target_comm[TASK_COMM_LEN]; 221 222 struct audit_tree_refs *trees, *first_trees; 223 struct list_head killed_trees; 224 int tree_count; 225 226 int type; 227 union { 228 struct { 229 int nargs; 230 long args[6]; 231 } socketcall; 232 struct { 233 uid_t uid; 234 gid_t gid; 235 umode_t mode; 236 u32 osid; 237 int has_perm; 238 uid_t perm_uid; 239 gid_t perm_gid; 240 umode_t perm_mode; 241 unsigned long qbytes; 242 } ipc; 243 struct { 244 mqd_t mqdes; 245 struct mq_attr mqstat; 246 } mq_getsetattr; 247 struct { 248 mqd_t mqdes; 249 int sigev_signo; 250 } mq_notify; 251 struct { 252 mqd_t mqdes; 253 size_t msg_len; 254 unsigned int msg_prio; 255 struct timespec abs_timeout; 256 } mq_sendrecv; 257 struct { 258 int oflag; 259 umode_t mode; 260 struct mq_attr attr; 261 } mq_open; 262 struct { 263 pid_t pid; 264 struct audit_cap_data cap; 265 } capset; 266 struct { 267 int fd; 268 int flags; 269 } mmap; 270 }; 271 int fds[2]; 272 273 #if AUDIT_DEBUG 274 int put_count; 275 int ino_count; 276 #endif 277 }; 278 279 static inline int open_arg(int flags, int mask) 280 { 281 int n = ACC_MODE(flags); 282 if (flags & (O_TRUNC | O_CREAT)) 283 n |= AUDIT_PERM_WRITE; 284 return n & mask; 285 } 286 287 static int audit_match_perm(struct audit_context *ctx, int mask) 288 { 289 unsigned n; 290 if (unlikely(!ctx)) 291 return 0; 292 n = ctx->major; 293 294 switch (audit_classify_syscall(ctx->arch, n)) { 295 case 0: /* native */ 296 if ((mask & AUDIT_PERM_WRITE) && 297 audit_match_class(AUDIT_CLASS_WRITE, n)) 298 return 1; 299 if ((mask & AUDIT_PERM_READ) && 300 audit_match_class(AUDIT_CLASS_READ, n)) 301 return 1; 302 if ((mask & AUDIT_PERM_ATTR) && 303 audit_match_class(AUDIT_CLASS_CHATTR, n)) 304 return 1; 305 return 0; 306 case 1: /* 32bit on biarch */ 307 if ((mask & AUDIT_PERM_WRITE) && 308 audit_match_class(AUDIT_CLASS_WRITE_32, n)) 309 return 1; 310 if ((mask & AUDIT_PERM_READ) && 311 audit_match_class(AUDIT_CLASS_READ_32, n)) 312 return 1; 313 if ((mask & AUDIT_PERM_ATTR) && 314 audit_match_class(AUDIT_CLASS_CHATTR_32, n)) 315 return 1; 316 return 0; 317 case 2: /* open */ 318 return mask & ACC_MODE(ctx->argv[1]); 319 case 3: /* openat */ 320 return mask & ACC_MODE(ctx->argv[2]); 321 case 4: /* socketcall */ 322 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); 323 case 5: /* execve */ 324 return mask & AUDIT_PERM_EXEC; 325 default: 326 return 0; 327 } 328 } 329 330 static int audit_match_filetype(struct audit_context *ctx, int val) 331 { 332 struct audit_names *n; 333 umode_t mode = (umode_t)val; 334 335 if (unlikely(!ctx)) 336 return 0; 337 338 list_for_each_entry(n, &ctx->names_list, list) { 339 if ((n->ino != -1) && 340 ((n->mode & S_IFMT) == mode)) 341 return 1; 342 } 343 344 return 0; 345 } 346 347 /* 348 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *; 349 * ->first_trees points to its beginning, ->trees - to the current end of data. 350 * ->tree_count is the number of free entries in array pointed to by ->trees. 351 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL, 352 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously, 353 * it's going to remain 1-element for almost any setup) until we free context itself. 354 * References in it _are_ dropped - at the same time we free/drop aux stuff. 355 */ 356 357 #ifdef CONFIG_AUDIT_TREE 358 static void audit_set_auditable(struct audit_context *ctx) 359 { 360 if (!ctx->prio) { 361 ctx->prio = 1; 362 ctx->current_state = AUDIT_RECORD_CONTEXT; 363 } 364 } 365 366 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk) 367 { 368 struct audit_tree_refs *p = ctx->trees; 369 int left = ctx->tree_count; 370 if (likely(left)) { 371 p->c[--left] = chunk; 372 ctx->tree_count = left; 373 return 1; 374 } 375 if (!p) 376 return 0; 377 p = p->next; 378 if (p) { 379 p->c[30] = chunk; 380 ctx->trees = p; 381 ctx->tree_count = 30; 382 return 1; 383 } 384 return 0; 385 } 386 387 static int grow_tree_refs(struct audit_context *ctx) 388 { 389 struct audit_tree_refs *p = ctx->trees; 390 ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL); 391 if (!ctx->trees) { 392 ctx->trees = p; 393 return 0; 394 } 395 if (p) 396 p->next = ctx->trees; 397 else 398 ctx->first_trees = ctx->trees; 399 ctx->tree_count = 31; 400 return 1; 401 } 402 #endif 403 404 static void unroll_tree_refs(struct audit_context *ctx, 405 struct audit_tree_refs *p, int count) 406 { 407 #ifdef CONFIG_AUDIT_TREE 408 struct audit_tree_refs *q; 409 int n; 410 if (!p) { 411 /* we started with empty chain */ 412 p = ctx->first_trees; 413 count = 31; 414 /* if the very first allocation has failed, nothing to do */ 415 if (!p) 416 return; 417 } 418 n = count; 419 for (q = p; q != ctx->trees; q = q->next, n = 31) { 420 while (n--) { 421 audit_put_chunk(q->c[n]); 422 q->c[n] = NULL; 423 } 424 } 425 while (n-- > ctx->tree_count) { 426 audit_put_chunk(q->c[n]); 427 q->c[n] = NULL; 428 } 429 ctx->trees = p; 430 ctx->tree_count = count; 431 #endif 432 } 433 434 static void free_tree_refs(struct audit_context *ctx) 435 { 436 struct audit_tree_refs *p, *q; 437 for (p = ctx->first_trees; p; p = q) { 438 q = p->next; 439 kfree(p); 440 } 441 } 442 443 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree) 444 { 445 #ifdef CONFIG_AUDIT_TREE 446 struct audit_tree_refs *p; 447 int n; 448 if (!tree) 449 return 0; 450 /* full ones */ 451 for (p = ctx->first_trees; p != ctx->trees; p = p->next) { 452 for (n = 0; n < 31; n++) 453 if (audit_tree_match(p->c[n], tree)) 454 return 1; 455 } 456 /* partial */ 457 if (p) { 458 for (n = ctx->tree_count; n < 31; n++) 459 if (audit_tree_match(p->c[n], tree)) 460 return 1; 461 } 462 #endif 463 return 0; 464 } 465 466 static int audit_compare_id(uid_t uid1, 467 struct audit_names *name, 468 unsigned long name_offset, 469 struct audit_field *f, 470 struct audit_context *ctx) 471 { 472 struct audit_names *n; 473 unsigned long addr; 474 uid_t uid2; 475 int rc; 476 477 BUILD_BUG_ON(sizeof(uid_t) != sizeof(gid_t)); 478 479 if (name) { 480 addr = (unsigned long)name; 481 addr += name_offset; 482 483 uid2 = *(uid_t *)addr; 484 rc = audit_comparator(uid1, f->op, uid2); 485 if (rc) 486 return rc; 487 } 488 489 if (ctx) { 490 list_for_each_entry(n, &ctx->names_list, list) { 491 addr = (unsigned long)n; 492 addr += name_offset; 493 494 uid2 = *(uid_t *)addr; 495 496 rc = audit_comparator(uid1, f->op, uid2); 497 if (rc) 498 return rc; 499 } 500 } 501 return 0; 502 } 503 504 static int audit_field_compare(struct task_struct *tsk, 505 const struct cred *cred, 506 struct audit_field *f, 507 struct audit_context *ctx, 508 struct audit_names *name) 509 { 510 switch (f->val) { 511 /* process to file object comparisons */ 512 case AUDIT_COMPARE_UID_TO_OBJ_UID: 513 return audit_compare_id(cred->uid, 514 name, offsetof(struct audit_names, uid), 515 f, ctx); 516 case AUDIT_COMPARE_GID_TO_OBJ_GID: 517 return audit_compare_id(cred->gid, 518 name, offsetof(struct audit_names, gid), 519 f, ctx); 520 case AUDIT_COMPARE_EUID_TO_OBJ_UID: 521 return audit_compare_id(cred->euid, 522 name, offsetof(struct audit_names, uid), 523 f, ctx); 524 case AUDIT_COMPARE_EGID_TO_OBJ_GID: 525 return audit_compare_id(cred->egid, 526 name, offsetof(struct audit_names, gid), 527 f, ctx); 528 case AUDIT_COMPARE_AUID_TO_OBJ_UID: 529 return audit_compare_id(tsk->loginuid, 530 name, offsetof(struct audit_names, uid), 531 f, ctx); 532 case AUDIT_COMPARE_SUID_TO_OBJ_UID: 533 return audit_compare_id(cred->suid, 534 name, offsetof(struct audit_names, uid), 535 f, ctx); 536 case AUDIT_COMPARE_SGID_TO_OBJ_GID: 537 return audit_compare_id(cred->sgid, 538 name, offsetof(struct audit_names, gid), 539 f, ctx); 540 case AUDIT_COMPARE_FSUID_TO_OBJ_UID: 541 return audit_compare_id(cred->fsuid, 542 name, offsetof(struct audit_names, uid), 543 f, ctx); 544 case AUDIT_COMPARE_FSGID_TO_OBJ_GID: 545 return audit_compare_id(cred->fsgid, 546 name, offsetof(struct audit_names, gid), 547 f, ctx); 548 /* uid comparisons */ 549 case AUDIT_COMPARE_UID_TO_AUID: 550 return audit_comparator(cred->uid, f->op, tsk->loginuid); 551 case AUDIT_COMPARE_UID_TO_EUID: 552 return audit_comparator(cred->uid, f->op, cred->euid); 553 case AUDIT_COMPARE_UID_TO_SUID: 554 return audit_comparator(cred->uid, f->op, cred->suid); 555 case AUDIT_COMPARE_UID_TO_FSUID: 556 return audit_comparator(cred->uid, f->op, cred->fsuid); 557 /* auid comparisons */ 558 case AUDIT_COMPARE_AUID_TO_EUID: 559 return audit_comparator(tsk->loginuid, f->op, cred->euid); 560 case AUDIT_COMPARE_AUID_TO_SUID: 561 return audit_comparator(tsk->loginuid, f->op, cred->suid); 562 case AUDIT_COMPARE_AUID_TO_FSUID: 563 return audit_comparator(tsk->loginuid, f->op, cred->fsuid); 564 /* euid comparisons */ 565 case AUDIT_COMPARE_EUID_TO_SUID: 566 return audit_comparator(cred->euid, f->op, cred->suid); 567 case AUDIT_COMPARE_EUID_TO_FSUID: 568 return audit_comparator(cred->euid, f->op, cred->fsuid); 569 /* suid comparisons */ 570 case AUDIT_COMPARE_SUID_TO_FSUID: 571 return audit_comparator(cred->suid, f->op, cred->fsuid); 572 /* gid comparisons */ 573 case AUDIT_COMPARE_GID_TO_EGID: 574 return audit_comparator(cred->gid, f->op, cred->egid); 575 case AUDIT_COMPARE_GID_TO_SGID: 576 return audit_comparator(cred->gid, f->op, cred->sgid); 577 case AUDIT_COMPARE_GID_TO_FSGID: 578 return audit_comparator(cred->gid, f->op, cred->fsgid); 579 /* egid comparisons */ 580 case AUDIT_COMPARE_EGID_TO_SGID: 581 return audit_comparator(cred->egid, f->op, cred->sgid); 582 case AUDIT_COMPARE_EGID_TO_FSGID: 583 return audit_comparator(cred->egid, f->op, cred->fsgid); 584 /* sgid comparison */ 585 case AUDIT_COMPARE_SGID_TO_FSGID: 586 return audit_comparator(cred->sgid, f->op, cred->fsgid); 587 default: 588 WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n"); 589 return 0; 590 } 591 return 0; 592 } 593 594 /* Determine if any context name data matches a rule's watch data */ 595 /* Compare a task_struct with an audit_rule. Return 1 on match, 0 596 * otherwise. 597 * 598 * If task_creation is true, this is an explicit indication that we are 599 * filtering a task rule at task creation time. This and tsk == current are 600 * the only situations where tsk->cred may be accessed without an rcu read lock. 601 */ 602 static int audit_filter_rules(struct task_struct *tsk, 603 struct audit_krule *rule, 604 struct audit_context *ctx, 605 struct audit_names *name, 606 enum audit_state *state, 607 bool task_creation) 608 { 609 const struct cred *cred; 610 int i, need_sid = 1; 611 u32 sid; 612 613 cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation); 614 615 for (i = 0; i < rule->field_count; i++) { 616 struct audit_field *f = &rule->fields[i]; 617 struct audit_names *n; 618 int result = 0; 619 620 switch (f->type) { 621 case AUDIT_PID: 622 result = audit_comparator(tsk->pid, f->op, f->val); 623 break; 624 case AUDIT_PPID: 625 if (ctx) { 626 if (!ctx->ppid) 627 ctx->ppid = sys_getppid(); 628 result = audit_comparator(ctx->ppid, f->op, f->val); 629 } 630 break; 631 case AUDIT_UID: 632 result = audit_comparator(cred->uid, f->op, f->val); 633 break; 634 case AUDIT_EUID: 635 result = audit_comparator(cred->euid, f->op, f->val); 636 break; 637 case AUDIT_SUID: 638 result = audit_comparator(cred->suid, f->op, f->val); 639 break; 640 case AUDIT_FSUID: 641 result = audit_comparator(cred->fsuid, f->op, f->val); 642 break; 643 case AUDIT_GID: 644 result = audit_comparator(cred->gid, f->op, f->val); 645 break; 646 case AUDIT_EGID: 647 result = audit_comparator(cred->egid, f->op, f->val); 648 break; 649 case AUDIT_SGID: 650 result = audit_comparator(cred->sgid, f->op, f->val); 651 break; 652 case AUDIT_FSGID: 653 result = audit_comparator(cred->fsgid, f->op, f->val); 654 break; 655 case AUDIT_PERS: 656 result = audit_comparator(tsk->personality, f->op, f->val); 657 break; 658 case AUDIT_ARCH: 659 if (ctx) 660 result = audit_comparator(ctx->arch, f->op, f->val); 661 break; 662 663 case AUDIT_EXIT: 664 if (ctx && ctx->return_valid) 665 result = audit_comparator(ctx->return_code, f->op, f->val); 666 break; 667 case AUDIT_SUCCESS: 668 if (ctx && ctx->return_valid) { 669 if (f->val) 670 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS); 671 else 672 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE); 673 } 674 break; 675 case AUDIT_DEVMAJOR: 676 if (name) { 677 if (audit_comparator(MAJOR(name->dev), f->op, f->val) || 678 audit_comparator(MAJOR(name->rdev), f->op, f->val)) 679 ++result; 680 } else if (ctx) { 681 list_for_each_entry(n, &ctx->names_list, list) { 682 if (audit_comparator(MAJOR(n->dev), f->op, f->val) || 683 audit_comparator(MAJOR(n->rdev), f->op, f->val)) { 684 ++result; 685 break; 686 } 687 } 688 } 689 break; 690 case AUDIT_DEVMINOR: 691 if (name) { 692 if (audit_comparator(MINOR(name->dev), f->op, f->val) || 693 audit_comparator(MINOR(name->rdev), f->op, f->val)) 694 ++result; 695 } else if (ctx) { 696 list_for_each_entry(n, &ctx->names_list, list) { 697 if (audit_comparator(MINOR(n->dev), f->op, f->val) || 698 audit_comparator(MINOR(n->rdev), f->op, f->val)) { 699 ++result; 700 break; 701 } 702 } 703 } 704 break; 705 case AUDIT_INODE: 706 if (name) 707 result = (name->ino == f->val); 708 else if (ctx) { 709 list_for_each_entry(n, &ctx->names_list, list) { 710 if (audit_comparator(n->ino, f->op, f->val)) { 711 ++result; 712 break; 713 } 714 } 715 } 716 break; 717 case AUDIT_OBJ_UID: 718 if (name) { 719 result = audit_comparator(name->uid, f->op, f->val); 720 } else if (ctx) { 721 list_for_each_entry(n, &ctx->names_list, list) { 722 if (audit_comparator(n->uid, f->op, f->val)) { 723 ++result; 724 break; 725 } 726 } 727 } 728 break; 729 case AUDIT_OBJ_GID: 730 if (name) { 731 result = audit_comparator(name->gid, f->op, f->val); 732 } else if (ctx) { 733 list_for_each_entry(n, &ctx->names_list, list) { 734 if (audit_comparator(n->gid, f->op, f->val)) { 735 ++result; 736 break; 737 } 738 } 739 } 740 break; 741 case AUDIT_WATCH: 742 if (name) 743 result = audit_watch_compare(rule->watch, name->ino, name->dev); 744 break; 745 case AUDIT_DIR: 746 if (ctx) 747 result = match_tree_refs(ctx, rule->tree); 748 break; 749 case AUDIT_LOGINUID: 750 result = 0; 751 if (ctx) 752 result = audit_comparator(tsk->loginuid, f->op, f->val); 753 break; 754 case AUDIT_SUBJ_USER: 755 case AUDIT_SUBJ_ROLE: 756 case AUDIT_SUBJ_TYPE: 757 case AUDIT_SUBJ_SEN: 758 case AUDIT_SUBJ_CLR: 759 /* NOTE: this may return negative values indicating 760 a temporary error. We simply treat this as a 761 match for now to avoid losing information that 762 may be wanted. An error message will also be 763 logged upon error */ 764 if (f->lsm_rule) { 765 if (need_sid) { 766 security_task_getsecid(tsk, &sid); 767 need_sid = 0; 768 } 769 result = security_audit_rule_match(sid, f->type, 770 f->op, 771 f->lsm_rule, 772 ctx); 773 } 774 break; 775 case AUDIT_OBJ_USER: 776 case AUDIT_OBJ_ROLE: 777 case AUDIT_OBJ_TYPE: 778 case AUDIT_OBJ_LEV_LOW: 779 case AUDIT_OBJ_LEV_HIGH: 780 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR 781 also applies here */ 782 if (f->lsm_rule) { 783 /* Find files that match */ 784 if (name) { 785 result = security_audit_rule_match( 786 name->osid, f->type, f->op, 787 f->lsm_rule, ctx); 788 } else if (ctx) { 789 list_for_each_entry(n, &ctx->names_list, list) { 790 if (security_audit_rule_match(n->osid, f->type, 791 f->op, f->lsm_rule, 792 ctx)) { 793 ++result; 794 break; 795 } 796 } 797 } 798 /* Find ipc objects that match */ 799 if (!ctx || ctx->type != AUDIT_IPC) 800 break; 801 if (security_audit_rule_match(ctx->ipc.osid, 802 f->type, f->op, 803 f->lsm_rule, ctx)) 804 ++result; 805 } 806 break; 807 case AUDIT_ARG0: 808 case AUDIT_ARG1: 809 case AUDIT_ARG2: 810 case AUDIT_ARG3: 811 if (ctx) 812 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val); 813 break; 814 case AUDIT_FILTERKEY: 815 /* ignore this field for filtering */ 816 result = 1; 817 break; 818 case AUDIT_PERM: 819 result = audit_match_perm(ctx, f->val); 820 break; 821 case AUDIT_FILETYPE: 822 result = audit_match_filetype(ctx, f->val); 823 break; 824 case AUDIT_FIELD_COMPARE: 825 result = audit_field_compare(tsk, cred, f, ctx, name); 826 break; 827 } 828 if (!result) 829 return 0; 830 } 831 832 if (ctx) { 833 if (rule->prio <= ctx->prio) 834 return 0; 835 if (rule->filterkey) { 836 kfree(ctx->filterkey); 837 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC); 838 } 839 ctx->prio = rule->prio; 840 } 841 switch (rule->action) { 842 case AUDIT_NEVER: *state = AUDIT_DISABLED; break; 843 case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; 844 } 845 return 1; 846 } 847 848 /* At process creation time, we can determine if system-call auditing is 849 * completely disabled for this task. Since we only have the task 850 * structure at this point, we can only check uid and gid. 851 */ 852 static enum audit_state audit_filter_task(struct task_struct *tsk, char **key) 853 { 854 struct audit_entry *e; 855 enum audit_state state; 856 857 rcu_read_lock(); 858 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { 859 if (audit_filter_rules(tsk, &e->rule, NULL, NULL, 860 &state, true)) { 861 if (state == AUDIT_RECORD_CONTEXT) 862 *key = kstrdup(e->rule.filterkey, GFP_ATOMIC); 863 rcu_read_unlock(); 864 return state; 865 } 866 } 867 rcu_read_unlock(); 868 return AUDIT_BUILD_CONTEXT; 869 } 870 871 /* At syscall entry and exit time, this filter is called if the 872 * audit_state is not low enough that auditing cannot take place, but is 873 * also not high enough that we already know we have to write an audit 874 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). 875 */ 876 static enum audit_state audit_filter_syscall(struct task_struct *tsk, 877 struct audit_context *ctx, 878 struct list_head *list) 879 { 880 struct audit_entry *e; 881 enum audit_state state; 882 883 if (audit_pid && tsk->tgid == audit_pid) 884 return AUDIT_DISABLED; 885 886 rcu_read_lock(); 887 if (!list_empty(list)) { 888 int word = AUDIT_WORD(ctx->major); 889 int bit = AUDIT_BIT(ctx->major); 890 891 list_for_each_entry_rcu(e, list, list) { 892 if ((e->rule.mask[word] & bit) == bit && 893 audit_filter_rules(tsk, &e->rule, ctx, NULL, 894 &state, false)) { 895 rcu_read_unlock(); 896 ctx->current_state = state; 897 return state; 898 } 899 } 900 } 901 rcu_read_unlock(); 902 return AUDIT_BUILD_CONTEXT; 903 } 904 905 /* 906 * Given an audit_name check the inode hash table to see if they match. 907 * Called holding the rcu read lock to protect the use of audit_inode_hash 908 */ 909 static int audit_filter_inode_name(struct task_struct *tsk, 910 struct audit_names *n, 911 struct audit_context *ctx) { 912 int word, bit; 913 int h = audit_hash_ino((u32)n->ino); 914 struct list_head *list = &audit_inode_hash[h]; 915 struct audit_entry *e; 916 enum audit_state state; 917 918 word = AUDIT_WORD(ctx->major); 919 bit = AUDIT_BIT(ctx->major); 920 921 if (list_empty(list)) 922 return 0; 923 924 list_for_each_entry_rcu(e, list, list) { 925 if ((e->rule.mask[word] & bit) == bit && 926 audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) { 927 ctx->current_state = state; 928 return 1; 929 } 930 } 931 932 return 0; 933 } 934 935 /* At syscall exit time, this filter is called if any audit_names have been 936 * collected during syscall processing. We only check rules in sublists at hash 937 * buckets applicable to the inode numbers in audit_names. 938 * Regarding audit_state, same rules apply as for audit_filter_syscall(). 939 */ 940 void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx) 941 { 942 struct audit_names *n; 943 944 if (audit_pid && tsk->tgid == audit_pid) 945 return; 946 947 rcu_read_lock(); 948 949 list_for_each_entry(n, &ctx->names_list, list) { 950 if (audit_filter_inode_name(tsk, n, ctx)) 951 break; 952 } 953 rcu_read_unlock(); 954 } 955 956 static inline struct audit_context *audit_get_context(struct task_struct *tsk, 957 int return_valid, 958 long return_code) 959 { 960 struct audit_context *context = tsk->audit_context; 961 962 if (!context) 963 return NULL; 964 context->return_valid = return_valid; 965 966 /* 967 * we need to fix up the return code in the audit logs if the actual 968 * return codes are later going to be fixed up by the arch specific 969 * signal handlers 970 * 971 * This is actually a test for: 972 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) || 973 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK) 974 * 975 * but is faster than a bunch of || 976 */ 977 if (unlikely(return_code <= -ERESTARTSYS) && 978 (return_code >= -ERESTART_RESTARTBLOCK) && 979 (return_code != -ENOIOCTLCMD)) 980 context->return_code = -EINTR; 981 else 982 context->return_code = return_code; 983 984 if (context->in_syscall && !context->dummy) { 985 audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]); 986 audit_filter_inodes(tsk, context); 987 } 988 989 tsk->audit_context = NULL; 990 return context; 991 } 992 993 static inline void audit_free_names(struct audit_context *context) 994 { 995 struct audit_names *n, *next; 996 997 #if AUDIT_DEBUG == 2 998 if (context->put_count + context->ino_count != context->name_count) { 999 printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d" 1000 " name_count=%d put_count=%d" 1001 " ino_count=%d [NOT freeing]\n", 1002 __FILE__, __LINE__, 1003 context->serial, context->major, context->in_syscall, 1004 context->name_count, context->put_count, 1005 context->ino_count); 1006 list_for_each_entry(n, &context->names_list, list) { 1007 printk(KERN_ERR "names[%d] = %p = %s\n", i, 1008 n->name, n->name ?: "(null)"); 1009 } 1010 dump_stack(); 1011 return; 1012 } 1013 #endif 1014 #if AUDIT_DEBUG 1015 context->put_count = 0; 1016 context->ino_count = 0; 1017 #endif 1018 1019 list_for_each_entry_safe(n, next, &context->names_list, list) { 1020 list_del(&n->list); 1021 if (n->name && n->name_put) 1022 __putname(n->name); 1023 if (n->should_free) 1024 kfree(n); 1025 } 1026 context->name_count = 0; 1027 path_put(&context->pwd); 1028 context->pwd.dentry = NULL; 1029 context->pwd.mnt = NULL; 1030 } 1031 1032 static inline void audit_free_aux(struct audit_context *context) 1033 { 1034 struct audit_aux_data *aux; 1035 1036 while ((aux = context->aux)) { 1037 context->aux = aux->next; 1038 kfree(aux); 1039 } 1040 while ((aux = context->aux_pids)) { 1041 context->aux_pids = aux->next; 1042 kfree(aux); 1043 } 1044 } 1045 1046 static inline void audit_zero_context(struct audit_context *context, 1047 enum audit_state state) 1048 { 1049 memset(context, 0, sizeof(*context)); 1050 context->state = state; 1051 context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 1052 } 1053 1054 static inline struct audit_context *audit_alloc_context(enum audit_state state) 1055 { 1056 struct audit_context *context; 1057 1058 if (!(context = kmalloc(sizeof(*context), GFP_KERNEL))) 1059 return NULL; 1060 audit_zero_context(context, state); 1061 INIT_LIST_HEAD(&context->killed_trees); 1062 INIT_LIST_HEAD(&context->names_list); 1063 return context; 1064 } 1065 1066 /** 1067 * audit_alloc - allocate an audit context block for a task 1068 * @tsk: task 1069 * 1070 * Filter on the task information and allocate a per-task audit context 1071 * if necessary. Doing so turns on system call auditing for the 1072 * specified task. This is called from copy_process, so no lock is 1073 * needed. 1074 */ 1075 int audit_alloc(struct task_struct *tsk) 1076 { 1077 struct audit_context *context; 1078 enum audit_state state; 1079 char *key = NULL; 1080 1081 if (likely(!audit_ever_enabled)) 1082 return 0; /* Return if not auditing. */ 1083 1084 state = audit_filter_task(tsk, &key); 1085 if (state == AUDIT_DISABLED) 1086 return 0; 1087 1088 if (!(context = audit_alloc_context(state))) { 1089 kfree(key); 1090 audit_log_lost("out of memory in audit_alloc"); 1091 return -ENOMEM; 1092 } 1093 context->filterkey = key; 1094 1095 tsk->audit_context = context; 1096 set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); 1097 return 0; 1098 } 1099 1100 static inline void audit_free_context(struct audit_context *context) 1101 { 1102 struct audit_context *previous; 1103 int count = 0; 1104 1105 do { 1106 previous = context->previous; 1107 if (previous || (count && count < 10)) { 1108 ++count; 1109 printk(KERN_ERR "audit(:%d): major=%d name_count=%d:" 1110 " freeing multiple contexts (%d)\n", 1111 context->serial, context->major, 1112 context->name_count, count); 1113 } 1114 audit_free_names(context); 1115 unroll_tree_refs(context, NULL, 0); 1116 free_tree_refs(context); 1117 audit_free_aux(context); 1118 kfree(context->filterkey); 1119 kfree(context->sockaddr); 1120 kfree(context); 1121 context = previous; 1122 } while (context); 1123 if (count >= 10) 1124 printk(KERN_ERR "audit: freed %d contexts\n", count); 1125 } 1126 1127 void audit_log_task_context(struct audit_buffer *ab) 1128 { 1129 char *ctx = NULL; 1130 unsigned len; 1131 int error; 1132 u32 sid; 1133 1134 security_task_getsecid(current, &sid); 1135 if (!sid) 1136 return; 1137 1138 error = security_secid_to_secctx(sid, &ctx, &len); 1139 if (error) { 1140 if (error != -EINVAL) 1141 goto error_path; 1142 return; 1143 } 1144 1145 audit_log_format(ab, " subj=%s", ctx); 1146 security_release_secctx(ctx, len); 1147 return; 1148 1149 error_path: 1150 audit_panic("error in audit_log_task_context"); 1151 return; 1152 } 1153 1154 EXPORT_SYMBOL(audit_log_task_context); 1155 1156 static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk) 1157 { 1158 char name[sizeof(tsk->comm)]; 1159 struct mm_struct *mm = tsk->mm; 1160 struct vm_area_struct *vma; 1161 1162 /* tsk == current */ 1163 1164 get_task_comm(name, tsk); 1165 audit_log_format(ab, " comm="); 1166 audit_log_untrustedstring(ab, name); 1167 1168 if (mm) { 1169 down_read(&mm->mmap_sem); 1170 vma = mm->mmap; 1171 while (vma) { 1172 if ((vma->vm_flags & VM_EXECUTABLE) && 1173 vma->vm_file) { 1174 audit_log_d_path(ab, " exe=", 1175 &vma->vm_file->f_path); 1176 break; 1177 } 1178 vma = vma->vm_next; 1179 } 1180 up_read(&mm->mmap_sem); 1181 } 1182 audit_log_task_context(ab); 1183 } 1184 1185 static int audit_log_pid_context(struct audit_context *context, pid_t pid, 1186 uid_t auid, uid_t uid, unsigned int sessionid, 1187 u32 sid, char *comm) 1188 { 1189 struct audit_buffer *ab; 1190 char *ctx = NULL; 1191 u32 len; 1192 int rc = 0; 1193 1194 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); 1195 if (!ab) 1196 return rc; 1197 1198 audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid, 1199 uid, sessionid); 1200 if (security_secid_to_secctx(sid, &ctx, &len)) { 1201 audit_log_format(ab, " obj=(none)"); 1202 rc = 1; 1203 } else { 1204 audit_log_format(ab, " obj=%s", ctx); 1205 security_release_secctx(ctx, len); 1206 } 1207 audit_log_format(ab, " ocomm="); 1208 audit_log_untrustedstring(ab, comm); 1209 audit_log_end(ab); 1210 1211 return rc; 1212 } 1213 1214 /* 1215 * to_send and len_sent accounting are very loose estimates. We aren't 1216 * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being 1217 * within about 500 bytes (next page boundary) 1218 * 1219 * why snprintf? an int is up to 12 digits long. if we just assumed when 1220 * logging that a[%d]= was going to be 16 characters long we would be wasting 1221 * space in every audit message. In one 7500 byte message we can log up to 1222 * about 1000 min size arguments. That comes down to about 50% waste of space 1223 * if we didn't do the snprintf to find out how long arg_num_len was. 1224 */ 1225 static int audit_log_single_execve_arg(struct audit_context *context, 1226 struct audit_buffer **ab, 1227 int arg_num, 1228 size_t *len_sent, 1229 const char __user *p, 1230 char *buf) 1231 { 1232 char arg_num_len_buf[12]; 1233 const char __user *tmp_p = p; 1234 /* how many digits are in arg_num? 5 is the length of ' a=""' */ 1235 size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 5; 1236 size_t len, len_left, to_send; 1237 size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN; 1238 unsigned int i, has_cntl = 0, too_long = 0; 1239 int ret; 1240 1241 /* strnlen_user includes the null we don't want to send */ 1242 len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1; 1243 1244 /* 1245 * We just created this mm, if we can't find the strings 1246 * we just copied into it something is _very_ wrong. Similar 1247 * for strings that are too long, we should not have created 1248 * any. 1249 */ 1250 if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) { 1251 WARN_ON(1); 1252 send_sig(SIGKILL, current, 0); 1253 return -1; 1254 } 1255 1256 /* walk the whole argument looking for non-ascii chars */ 1257 do { 1258 if (len_left > MAX_EXECVE_AUDIT_LEN) 1259 to_send = MAX_EXECVE_AUDIT_LEN; 1260 else 1261 to_send = len_left; 1262 ret = copy_from_user(buf, tmp_p, to_send); 1263 /* 1264 * There is no reason for this copy to be short. We just 1265 * copied them here, and the mm hasn't been exposed to user- 1266 * space yet. 1267 */ 1268 if (ret) { 1269 WARN_ON(1); 1270 send_sig(SIGKILL, current, 0); 1271 return -1; 1272 } 1273 buf[to_send] = '\0'; 1274 has_cntl = audit_string_contains_control(buf, to_send); 1275 if (has_cntl) { 1276 /* 1277 * hex messages get logged as 2 bytes, so we can only 1278 * send half as much in each message 1279 */ 1280 max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2; 1281 break; 1282 } 1283 len_left -= to_send; 1284 tmp_p += to_send; 1285 } while (len_left > 0); 1286 1287 len_left = len; 1288 1289 if (len > max_execve_audit_len) 1290 too_long = 1; 1291 1292 /* rewalk the argument actually logging the message */ 1293 for (i = 0; len_left > 0; i++) { 1294 int room_left; 1295 1296 if (len_left > max_execve_audit_len) 1297 to_send = max_execve_audit_len; 1298 else 1299 to_send = len_left; 1300 1301 /* do we have space left to send this argument in this ab? */ 1302 room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent; 1303 if (has_cntl) 1304 room_left -= (to_send * 2); 1305 else 1306 room_left -= to_send; 1307 if (room_left < 0) { 1308 *len_sent = 0; 1309 audit_log_end(*ab); 1310 *ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE); 1311 if (!*ab) 1312 return 0; 1313 } 1314 1315 /* 1316 * first record needs to say how long the original string was 1317 * so we can be sure nothing was lost. 1318 */ 1319 if ((i == 0) && (too_long)) 1320 audit_log_format(*ab, " a%d_len=%zu", arg_num, 1321 has_cntl ? 2*len : len); 1322 1323 /* 1324 * normally arguments are small enough to fit and we already 1325 * filled buf above when we checked for control characters 1326 * so don't bother with another copy_from_user 1327 */ 1328 if (len >= max_execve_audit_len) 1329 ret = copy_from_user(buf, p, to_send); 1330 else 1331 ret = 0; 1332 if (ret) { 1333 WARN_ON(1); 1334 send_sig(SIGKILL, current, 0); 1335 return -1; 1336 } 1337 buf[to_send] = '\0'; 1338 1339 /* actually log it */ 1340 audit_log_format(*ab, " a%d", arg_num); 1341 if (too_long) 1342 audit_log_format(*ab, "[%d]", i); 1343 audit_log_format(*ab, "="); 1344 if (has_cntl) 1345 audit_log_n_hex(*ab, buf, to_send); 1346 else 1347 audit_log_string(*ab, buf); 1348 1349 p += to_send; 1350 len_left -= to_send; 1351 *len_sent += arg_num_len; 1352 if (has_cntl) 1353 *len_sent += to_send * 2; 1354 else 1355 *len_sent += to_send; 1356 } 1357 /* include the null we didn't log */ 1358 return len + 1; 1359 } 1360 1361 static void audit_log_execve_info(struct audit_context *context, 1362 struct audit_buffer **ab, 1363 struct audit_aux_data_execve *axi) 1364 { 1365 int i, len; 1366 size_t len_sent = 0; 1367 const char __user *p; 1368 char *buf; 1369 1370 if (axi->mm != current->mm) 1371 return; /* execve failed, no additional info */ 1372 1373 p = (const char __user *)axi->mm->arg_start; 1374 1375 audit_log_format(*ab, "argc=%d", axi->argc); 1376 1377 /* 1378 * we need some kernel buffer to hold the userspace args. Just 1379 * allocate one big one rather than allocating one of the right size 1380 * for every single argument inside audit_log_single_execve_arg() 1381 * should be <8k allocation so should be pretty safe. 1382 */ 1383 buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL); 1384 if (!buf) { 1385 audit_panic("out of memory for argv string\n"); 1386 return; 1387 } 1388 1389 for (i = 0; i < axi->argc; i++) { 1390 len = audit_log_single_execve_arg(context, ab, i, 1391 &len_sent, p, buf); 1392 if (len <= 0) 1393 break; 1394 p += len; 1395 } 1396 kfree(buf); 1397 } 1398 1399 static void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap) 1400 { 1401 int i; 1402 1403 audit_log_format(ab, " %s=", prefix); 1404 CAP_FOR_EACH_U32(i) { 1405 audit_log_format(ab, "%08x", cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]); 1406 } 1407 } 1408 1409 static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) 1410 { 1411 kernel_cap_t *perm = &name->fcap.permitted; 1412 kernel_cap_t *inh = &name->fcap.inheritable; 1413 int log = 0; 1414 1415 if (!cap_isclear(*perm)) { 1416 audit_log_cap(ab, "cap_fp", perm); 1417 log = 1; 1418 } 1419 if (!cap_isclear(*inh)) { 1420 audit_log_cap(ab, "cap_fi", inh); 1421 log = 1; 1422 } 1423 1424 if (log) 1425 audit_log_format(ab, " cap_fe=%d cap_fver=%x", name->fcap.fE, name->fcap_ver); 1426 } 1427 1428 static void show_special(struct audit_context *context, int *call_panic) 1429 { 1430 struct audit_buffer *ab; 1431 int i; 1432 1433 ab = audit_log_start(context, GFP_KERNEL, context->type); 1434 if (!ab) 1435 return; 1436 1437 switch (context->type) { 1438 case AUDIT_SOCKETCALL: { 1439 int nargs = context->socketcall.nargs; 1440 audit_log_format(ab, "nargs=%d", nargs); 1441 for (i = 0; i < nargs; i++) 1442 audit_log_format(ab, " a%d=%lx", i, 1443 context->socketcall.args[i]); 1444 break; } 1445 case AUDIT_IPC: { 1446 u32 osid = context->ipc.osid; 1447 1448 audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho", 1449 context->ipc.uid, context->ipc.gid, context->ipc.mode); 1450 if (osid) { 1451 char *ctx = NULL; 1452 u32 len; 1453 if (security_secid_to_secctx(osid, &ctx, &len)) { 1454 audit_log_format(ab, " osid=%u", osid); 1455 *call_panic = 1; 1456 } else { 1457 audit_log_format(ab, " obj=%s", ctx); 1458 security_release_secctx(ctx, len); 1459 } 1460 } 1461 if (context->ipc.has_perm) { 1462 audit_log_end(ab); 1463 ab = audit_log_start(context, GFP_KERNEL, 1464 AUDIT_IPC_SET_PERM); 1465 audit_log_format(ab, 1466 "qbytes=%lx ouid=%u ogid=%u mode=%#ho", 1467 context->ipc.qbytes, 1468 context->ipc.perm_uid, 1469 context->ipc.perm_gid, 1470 context->ipc.perm_mode); 1471 if (!ab) 1472 return; 1473 } 1474 break; } 1475 case AUDIT_MQ_OPEN: { 1476 audit_log_format(ab, 1477 "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld " 1478 "mq_msgsize=%ld mq_curmsgs=%ld", 1479 context->mq_open.oflag, context->mq_open.mode, 1480 context->mq_open.attr.mq_flags, 1481 context->mq_open.attr.mq_maxmsg, 1482 context->mq_open.attr.mq_msgsize, 1483 context->mq_open.attr.mq_curmsgs); 1484 break; } 1485 case AUDIT_MQ_SENDRECV: { 1486 audit_log_format(ab, 1487 "mqdes=%d msg_len=%zd msg_prio=%u " 1488 "abs_timeout_sec=%ld abs_timeout_nsec=%ld", 1489 context->mq_sendrecv.mqdes, 1490 context->mq_sendrecv.msg_len, 1491 context->mq_sendrecv.msg_prio, 1492 context->mq_sendrecv.abs_timeout.tv_sec, 1493 context->mq_sendrecv.abs_timeout.tv_nsec); 1494 break; } 1495 case AUDIT_MQ_NOTIFY: { 1496 audit_log_format(ab, "mqdes=%d sigev_signo=%d", 1497 context->mq_notify.mqdes, 1498 context->mq_notify.sigev_signo); 1499 break; } 1500 case AUDIT_MQ_GETSETATTR: { 1501 struct mq_attr *attr = &context->mq_getsetattr.mqstat; 1502 audit_log_format(ab, 1503 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld " 1504 "mq_curmsgs=%ld ", 1505 context->mq_getsetattr.mqdes, 1506 attr->mq_flags, attr->mq_maxmsg, 1507 attr->mq_msgsize, attr->mq_curmsgs); 1508 break; } 1509 case AUDIT_CAPSET: { 1510 audit_log_format(ab, "pid=%d", context->capset.pid); 1511 audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable); 1512 audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted); 1513 audit_log_cap(ab, "cap_pe", &context->capset.cap.effective); 1514 break; } 1515 case AUDIT_MMAP: { 1516 audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd, 1517 context->mmap.flags); 1518 break; } 1519 } 1520 audit_log_end(ab); 1521 } 1522 1523 static void audit_log_name(struct audit_context *context, struct audit_names *n, 1524 int record_num, int *call_panic) 1525 { 1526 struct audit_buffer *ab; 1527 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH); 1528 if (!ab) 1529 return; /* audit_panic has been called */ 1530 1531 audit_log_format(ab, "item=%d", record_num); 1532 1533 if (n->name) { 1534 switch (n->name_len) { 1535 case AUDIT_NAME_FULL: 1536 /* log the full path */ 1537 audit_log_format(ab, " name="); 1538 audit_log_untrustedstring(ab, n->name); 1539 break; 1540 case 0: 1541 /* name was specified as a relative path and the 1542 * directory component is the cwd */ 1543 audit_log_d_path(ab, " name=", &context->pwd); 1544 break; 1545 default: 1546 /* log the name's directory component */ 1547 audit_log_format(ab, " name="); 1548 audit_log_n_untrustedstring(ab, n->name, 1549 n->name_len); 1550 } 1551 } else 1552 audit_log_format(ab, " name=(null)"); 1553 1554 if (n->ino != (unsigned long)-1) { 1555 audit_log_format(ab, " inode=%lu" 1556 " dev=%02x:%02x mode=%#ho" 1557 " ouid=%u ogid=%u rdev=%02x:%02x", 1558 n->ino, 1559 MAJOR(n->dev), 1560 MINOR(n->dev), 1561 n->mode, 1562 n->uid, 1563 n->gid, 1564 MAJOR(n->rdev), 1565 MINOR(n->rdev)); 1566 } 1567 if (n->osid != 0) { 1568 char *ctx = NULL; 1569 u32 len; 1570 if (security_secid_to_secctx( 1571 n->osid, &ctx, &len)) { 1572 audit_log_format(ab, " osid=%u", n->osid); 1573 *call_panic = 2; 1574 } else { 1575 audit_log_format(ab, " obj=%s", ctx); 1576 security_release_secctx(ctx, len); 1577 } 1578 } 1579 1580 audit_log_fcaps(ab, n); 1581 1582 audit_log_end(ab); 1583 } 1584 1585 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk) 1586 { 1587 const struct cred *cred; 1588 int i, call_panic = 0; 1589 struct audit_buffer *ab; 1590 struct audit_aux_data *aux; 1591 const char *tty; 1592 struct audit_names *n; 1593 1594 /* tsk == current */ 1595 context->pid = tsk->pid; 1596 if (!context->ppid) 1597 context->ppid = sys_getppid(); 1598 cred = current_cred(); 1599 context->uid = cred->uid; 1600 context->gid = cred->gid; 1601 context->euid = cred->euid; 1602 context->suid = cred->suid; 1603 context->fsuid = cred->fsuid; 1604 context->egid = cred->egid; 1605 context->sgid = cred->sgid; 1606 context->fsgid = cred->fsgid; 1607 context->personality = tsk->personality; 1608 1609 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); 1610 if (!ab) 1611 return; /* audit_panic has been called */ 1612 audit_log_format(ab, "arch=%x syscall=%d", 1613 context->arch, context->major); 1614 if (context->personality != PER_LINUX) 1615 audit_log_format(ab, " per=%lx", context->personality); 1616 if (context->return_valid) 1617 audit_log_format(ab, " success=%s exit=%ld", 1618 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", 1619 context->return_code); 1620 1621 spin_lock_irq(&tsk->sighand->siglock); 1622 if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name) 1623 tty = tsk->signal->tty->name; 1624 else 1625 tty = "(none)"; 1626 spin_unlock_irq(&tsk->sighand->siglock); 1627 1628 audit_log_format(ab, 1629 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d" 1630 " ppid=%d pid=%d auid=%u uid=%u gid=%u" 1631 " euid=%u suid=%u fsuid=%u" 1632 " egid=%u sgid=%u fsgid=%u tty=%s ses=%u", 1633 context->argv[0], 1634 context->argv[1], 1635 context->argv[2], 1636 context->argv[3], 1637 context->name_count, 1638 context->ppid, 1639 context->pid, 1640 tsk->loginuid, 1641 context->uid, 1642 context->gid, 1643 context->euid, context->suid, context->fsuid, 1644 context->egid, context->sgid, context->fsgid, tty, 1645 tsk->sessionid); 1646 1647 1648 audit_log_task_info(ab, tsk); 1649 audit_log_key(ab, context->filterkey); 1650 audit_log_end(ab); 1651 1652 for (aux = context->aux; aux; aux = aux->next) { 1653 1654 ab = audit_log_start(context, GFP_KERNEL, aux->type); 1655 if (!ab) 1656 continue; /* audit_panic has been called */ 1657 1658 switch (aux->type) { 1659 1660 case AUDIT_EXECVE: { 1661 struct audit_aux_data_execve *axi = (void *)aux; 1662 audit_log_execve_info(context, &ab, axi); 1663 break; } 1664 1665 case AUDIT_BPRM_FCAPS: { 1666 struct audit_aux_data_bprm_fcaps *axs = (void *)aux; 1667 audit_log_format(ab, "fver=%x", axs->fcap_ver); 1668 audit_log_cap(ab, "fp", &axs->fcap.permitted); 1669 audit_log_cap(ab, "fi", &axs->fcap.inheritable); 1670 audit_log_format(ab, " fe=%d", axs->fcap.fE); 1671 audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted); 1672 audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable); 1673 audit_log_cap(ab, "old_pe", &axs->old_pcap.effective); 1674 audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted); 1675 audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable); 1676 audit_log_cap(ab, "new_pe", &axs->new_pcap.effective); 1677 break; } 1678 1679 } 1680 audit_log_end(ab); 1681 } 1682 1683 if (context->type) 1684 show_special(context, &call_panic); 1685 1686 if (context->fds[0] >= 0) { 1687 ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR); 1688 if (ab) { 1689 audit_log_format(ab, "fd0=%d fd1=%d", 1690 context->fds[0], context->fds[1]); 1691 audit_log_end(ab); 1692 } 1693 } 1694 1695 if (context->sockaddr_len) { 1696 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR); 1697 if (ab) { 1698 audit_log_format(ab, "saddr="); 1699 audit_log_n_hex(ab, (void *)context->sockaddr, 1700 context->sockaddr_len); 1701 audit_log_end(ab); 1702 } 1703 } 1704 1705 for (aux = context->aux_pids; aux; aux = aux->next) { 1706 struct audit_aux_data_pids *axs = (void *)aux; 1707 1708 for (i = 0; i < axs->pid_count; i++) 1709 if (audit_log_pid_context(context, axs->target_pid[i], 1710 axs->target_auid[i], 1711 axs->target_uid[i], 1712 axs->target_sessionid[i], 1713 axs->target_sid[i], 1714 axs->target_comm[i])) 1715 call_panic = 1; 1716 } 1717 1718 if (context->target_pid && 1719 audit_log_pid_context(context, context->target_pid, 1720 context->target_auid, context->target_uid, 1721 context->target_sessionid, 1722 context->target_sid, context->target_comm)) 1723 call_panic = 1; 1724 1725 if (context->pwd.dentry && context->pwd.mnt) { 1726 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); 1727 if (ab) { 1728 audit_log_d_path(ab, " cwd=", &context->pwd); 1729 audit_log_end(ab); 1730 } 1731 } 1732 1733 i = 0; 1734 list_for_each_entry(n, &context->names_list, list) 1735 audit_log_name(context, n, i++, &call_panic); 1736 1737 /* Send end of event record to help user space know we are finished */ 1738 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); 1739 if (ab) 1740 audit_log_end(ab); 1741 if (call_panic) 1742 audit_panic("error converting sid to string"); 1743 } 1744 1745 /** 1746 * audit_free - free a per-task audit context 1747 * @tsk: task whose audit context block to free 1748 * 1749 * Called from copy_process and do_exit 1750 */ 1751 void __audit_free(struct task_struct *tsk) 1752 { 1753 struct audit_context *context; 1754 1755 context = audit_get_context(tsk, 0, 0); 1756 if (!context) 1757 return; 1758 1759 /* Check for system calls that do not go through the exit 1760 * function (e.g., exit_group), then free context block. 1761 * We use GFP_ATOMIC here because we might be doing this 1762 * in the context of the idle thread */ 1763 /* that can happen only if we are called from do_exit() */ 1764 if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) 1765 audit_log_exit(context, tsk); 1766 if (!list_empty(&context->killed_trees)) 1767 audit_kill_trees(&context->killed_trees); 1768 1769 audit_free_context(context); 1770 } 1771 1772 /** 1773 * audit_syscall_entry - fill in an audit record at syscall entry 1774 * @arch: architecture type 1775 * @major: major syscall type (function) 1776 * @a1: additional syscall register 1 1777 * @a2: additional syscall register 2 1778 * @a3: additional syscall register 3 1779 * @a4: additional syscall register 4 1780 * 1781 * Fill in audit context at syscall entry. This only happens if the 1782 * audit context was created when the task was created and the state or 1783 * filters demand the audit context be built. If the state from the 1784 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, 1785 * then the record will be written at syscall exit time (otherwise, it 1786 * will only be written if another part of the kernel requests that it 1787 * be written). 1788 */ 1789 void __audit_syscall_entry(int arch, int major, 1790 unsigned long a1, unsigned long a2, 1791 unsigned long a3, unsigned long a4) 1792 { 1793 struct task_struct *tsk = current; 1794 struct audit_context *context = tsk->audit_context; 1795 enum audit_state state; 1796 1797 if (!context) 1798 return; 1799 1800 /* 1801 * This happens only on certain architectures that make system 1802 * calls in kernel_thread via the entry.S interface, instead of 1803 * with direct calls. (If you are porting to a new 1804 * architecture, hitting this condition can indicate that you 1805 * got the _exit/_leave calls backward in entry.S.) 1806 * 1807 * i386 no 1808 * x86_64 no 1809 * ppc64 yes (see arch/powerpc/platforms/iseries/misc.S) 1810 * 1811 * This also happens with vm86 emulation in a non-nested manner 1812 * (entries without exits), so this case must be caught. 1813 */ 1814 if (context->in_syscall) { 1815 struct audit_context *newctx; 1816 1817 #if AUDIT_DEBUG 1818 printk(KERN_ERR 1819 "audit(:%d) pid=%d in syscall=%d;" 1820 " entering syscall=%d\n", 1821 context->serial, tsk->pid, context->major, major); 1822 #endif 1823 newctx = audit_alloc_context(context->state); 1824 if (newctx) { 1825 newctx->previous = context; 1826 context = newctx; 1827 tsk->audit_context = newctx; 1828 } else { 1829 /* If we can't alloc a new context, the best we 1830 * can do is to leak memory (any pending putname 1831 * will be lost). The only other alternative is 1832 * to abandon auditing. */ 1833 audit_zero_context(context, context->state); 1834 } 1835 } 1836 BUG_ON(context->in_syscall || context->name_count); 1837 1838 if (!audit_enabled) 1839 return; 1840 1841 context->arch = arch; 1842 context->major = major; 1843 context->argv[0] = a1; 1844 context->argv[1] = a2; 1845 context->argv[2] = a3; 1846 context->argv[3] = a4; 1847 1848 state = context->state; 1849 context->dummy = !audit_n_rules; 1850 if (!context->dummy && state == AUDIT_BUILD_CONTEXT) { 1851 context->prio = 0; 1852 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]); 1853 } 1854 if (state == AUDIT_DISABLED) 1855 return; 1856 1857 context->serial = 0; 1858 context->ctime = CURRENT_TIME; 1859 context->in_syscall = 1; 1860 context->current_state = state; 1861 context->ppid = 0; 1862 } 1863 1864 /** 1865 * audit_syscall_exit - deallocate audit context after a system call 1866 * @success: success value of the syscall 1867 * @return_code: return value of the syscall 1868 * 1869 * Tear down after system call. If the audit context has been marked as 1870 * auditable (either because of the AUDIT_RECORD_CONTEXT state from 1871 * filtering, or because some other part of the kernel wrote an audit 1872 * message), then write out the syscall information. In call cases, 1873 * free the names stored from getname(). 1874 */ 1875 void __audit_syscall_exit(int success, long return_code) 1876 { 1877 struct task_struct *tsk = current; 1878 struct audit_context *context; 1879 1880 if (success) 1881 success = AUDITSC_SUCCESS; 1882 else 1883 success = AUDITSC_FAILURE; 1884 1885 context = audit_get_context(tsk, success, return_code); 1886 if (!context) 1887 return; 1888 1889 if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) 1890 audit_log_exit(context, tsk); 1891 1892 context->in_syscall = 0; 1893 context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 1894 1895 if (!list_empty(&context->killed_trees)) 1896 audit_kill_trees(&context->killed_trees); 1897 1898 if (context->previous) { 1899 struct audit_context *new_context = context->previous; 1900 context->previous = NULL; 1901 audit_free_context(context); 1902 tsk->audit_context = new_context; 1903 } else { 1904 audit_free_names(context); 1905 unroll_tree_refs(context, NULL, 0); 1906 audit_free_aux(context); 1907 context->aux = NULL; 1908 context->aux_pids = NULL; 1909 context->target_pid = 0; 1910 context->target_sid = 0; 1911 context->sockaddr_len = 0; 1912 context->type = 0; 1913 context->fds[0] = -1; 1914 if (context->state != AUDIT_RECORD_CONTEXT) { 1915 kfree(context->filterkey); 1916 context->filterkey = NULL; 1917 } 1918 tsk->audit_context = context; 1919 } 1920 } 1921 1922 static inline void handle_one(const struct inode *inode) 1923 { 1924 #ifdef CONFIG_AUDIT_TREE 1925 struct audit_context *context; 1926 struct audit_tree_refs *p; 1927 struct audit_chunk *chunk; 1928 int count; 1929 if (likely(hlist_empty(&inode->i_fsnotify_marks))) 1930 return; 1931 context = current->audit_context; 1932 p = context->trees; 1933 count = context->tree_count; 1934 rcu_read_lock(); 1935 chunk = audit_tree_lookup(inode); 1936 rcu_read_unlock(); 1937 if (!chunk) 1938 return; 1939 if (likely(put_tree_ref(context, chunk))) 1940 return; 1941 if (unlikely(!grow_tree_refs(context))) { 1942 printk(KERN_WARNING "out of memory, audit has lost a tree reference\n"); 1943 audit_set_auditable(context); 1944 audit_put_chunk(chunk); 1945 unroll_tree_refs(context, p, count); 1946 return; 1947 } 1948 put_tree_ref(context, chunk); 1949 #endif 1950 } 1951 1952 static void handle_path(const struct dentry *dentry) 1953 { 1954 #ifdef CONFIG_AUDIT_TREE 1955 struct audit_context *context; 1956 struct audit_tree_refs *p; 1957 const struct dentry *d, *parent; 1958 struct audit_chunk *drop; 1959 unsigned long seq; 1960 int count; 1961 1962 context = current->audit_context; 1963 p = context->trees; 1964 count = context->tree_count; 1965 retry: 1966 drop = NULL; 1967 d = dentry; 1968 rcu_read_lock(); 1969 seq = read_seqbegin(&rename_lock); 1970 for(;;) { 1971 struct inode *inode = d->d_inode; 1972 if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) { 1973 struct audit_chunk *chunk; 1974 chunk = audit_tree_lookup(inode); 1975 if (chunk) { 1976 if (unlikely(!put_tree_ref(context, chunk))) { 1977 drop = chunk; 1978 break; 1979 } 1980 } 1981 } 1982 parent = d->d_parent; 1983 if (parent == d) 1984 break; 1985 d = parent; 1986 } 1987 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */ 1988 rcu_read_unlock(); 1989 if (!drop) { 1990 /* just a race with rename */ 1991 unroll_tree_refs(context, p, count); 1992 goto retry; 1993 } 1994 audit_put_chunk(drop); 1995 if (grow_tree_refs(context)) { 1996 /* OK, got more space */ 1997 unroll_tree_refs(context, p, count); 1998 goto retry; 1999 } 2000 /* too bad */ 2001 printk(KERN_WARNING 2002 "out of memory, audit has lost a tree reference\n"); 2003 unroll_tree_refs(context, p, count); 2004 audit_set_auditable(context); 2005 return; 2006 } 2007 rcu_read_unlock(); 2008 #endif 2009 } 2010 2011 static struct audit_names *audit_alloc_name(struct audit_context *context) 2012 { 2013 struct audit_names *aname; 2014 2015 if (context->name_count < AUDIT_NAMES) { 2016 aname = &context->preallocated_names[context->name_count]; 2017 memset(aname, 0, sizeof(*aname)); 2018 } else { 2019 aname = kzalloc(sizeof(*aname), GFP_NOFS); 2020 if (!aname) 2021 return NULL; 2022 aname->should_free = true; 2023 } 2024 2025 aname->ino = (unsigned long)-1; 2026 list_add_tail(&aname->list, &context->names_list); 2027 2028 context->name_count++; 2029 #if AUDIT_DEBUG 2030 context->ino_count++; 2031 #endif 2032 return aname; 2033 } 2034 2035 /** 2036 * audit_getname - add a name to the list 2037 * @name: name to add 2038 * 2039 * Add a name to the list of audit names for this context. 2040 * Called from fs/namei.c:getname(). 2041 */ 2042 void __audit_getname(const char *name) 2043 { 2044 struct audit_context *context = current->audit_context; 2045 struct audit_names *n; 2046 2047 if (!context->in_syscall) { 2048 #if AUDIT_DEBUG == 2 2049 printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n", 2050 __FILE__, __LINE__, context->serial, name); 2051 dump_stack(); 2052 #endif 2053 return; 2054 } 2055 2056 n = audit_alloc_name(context); 2057 if (!n) 2058 return; 2059 2060 n->name = name; 2061 n->name_len = AUDIT_NAME_FULL; 2062 n->name_put = true; 2063 2064 if (!context->pwd.dentry) 2065 get_fs_pwd(current->fs, &context->pwd); 2066 } 2067 2068 /* audit_putname - intercept a putname request 2069 * @name: name to intercept and delay for putname 2070 * 2071 * If we have stored the name from getname in the audit context, 2072 * then we delay the putname until syscall exit. 2073 * Called from include/linux/fs.h:putname(). 2074 */ 2075 void audit_putname(const char *name) 2076 { 2077 struct audit_context *context = current->audit_context; 2078 2079 BUG_ON(!context); 2080 if (!context->in_syscall) { 2081 #if AUDIT_DEBUG == 2 2082 printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n", 2083 __FILE__, __LINE__, context->serial, name); 2084 if (context->name_count) { 2085 struct audit_names *n; 2086 int i; 2087 2088 list_for_each_entry(n, &context->names_list, list) 2089 printk(KERN_ERR "name[%d] = %p = %s\n", i, 2090 n->name, n->name ?: "(null)"); 2091 } 2092 #endif 2093 __putname(name); 2094 } 2095 #if AUDIT_DEBUG 2096 else { 2097 ++context->put_count; 2098 if (context->put_count > context->name_count) { 2099 printk(KERN_ERR "%s:%d(:%d): major=%d" 2100 " in_syscall=%d putname(%p) name_count=%d" 2101 " put_count=%d\n", 2102 __FILE__, __LINE__, 2103 context->serial, context->major, 2104 context->in_syscall, name, context->name_count, 2105 context->put_count); 2106 dump_stack(); 2107 } 2108 } 2109 #endif 2110 } 2111 2112 static inline int audit_copy_fcaps(struct audit_names *name, const struct dentry *dentry) 2113 { 2114 struct cpu_vfs_cap_data caps; 2115 int rc; 2116 2117 if (!dentry) 2118 return 0; 2119 2120 rc = get_vfs_caps_from_disk(dentry, &caps); 2121 if (rc) 2122 return rc; 2123 2124 name->fcap.permitted = caps.permitted; 2125 name->fcap.inheritable = caps.inheritable; 2126 name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 2127 name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; 2128 2129 return 0; 2130 } 2131 2132 2133 /* Copy inode data into an audit_names. */ 2134 static void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, 2135 const struct inode *inode) 2136 { 2137 name->ino = inode->i_ino; 2138 name->dev = inode->i_sb->s_dev; 2139 name->mode = inode->i_mode; 2140 name->uid = inode->i_uid; 2141 name->gid = inode->i_gid; 2142 name->rdev = inode->i_rdev; 2143 security_inode_getsecid(inode, &name->osid); 2144 audit_copy_fcaps(name, dentry); 2145 } 2146 2147 /** 2148 * audit_inode - store the inode and device from a lookup 2149 * @name: name being audited 2150 * @dentry: dentry being audited 2151 * 2152 * Called from fs/namei.c:path_lookup(). 2153 */ 2154 void __audit_inode(const char *name, const struct dentry *dentry) 2155 { 2156 struct audit_context *context = current->audit_context; 2157 const struct inode *inode = dentry->d_inode; 2158 struct audit_names *n; 2159 2160 if (!context->in_syscall) 2161 return; 2162 2163 list_for_each_entry_reverse(n, &context->names_list, list) { 2164 if (n->name && (n->name == name)) 2165 goto out; 2166 } 2167 2168 /* unable to find the name from a previous getname() */ 2169 n = audit_alloc_name(context); 2170 if (!n) 2171 return; 2172 out: 2173 handle_path(dentry); 2174 audit_copy_inode(n, dentry, inode); 2175 } 2176 2177 /** 2178 * audit_inode_child - collect inode info for created/removed objects 2179 * @dentry: dentry being audited 2180 * @parent: inode of dentry parent 2181 * 2182 * For syscalls that create or remove filesystem objects, audit_inode 2183 * can only collect information for the filesystem object's parent. 2184 * This call updates the audit context with the child's information. 2185 * Syscalls that create a new filesystem object must be hooked after 2186 * the object is created. Syscalls that remove a filesystem object 2187 * must be hooked prior, in order to capture the target inode during 2188 * unsuccessful attempts. 2189 */ 2190 void __audit_inode_child(const struct dentry *dentry, 2191 const struct inode *parent) 2192 { 2193 struct audit_context *context = current->audit_context; 2194 const char *found_parent = NULL, *found_child = NULL; 2195 const struct inode *inode = dentry->d_inode; 2196 const char *dname = dentry->d_name.name; 2197 struct audit_names *n; 2198 int dirlen = 0; 2199 2200 if (!context->in_syscall) 2201 return; 2202 2203 if (inode) 2204 handle_one(inode); 2205 2206 /* parent is more likely, look for it first */ 2207 list_for_each_entry(n, &context->names_list, list) { 2208 if (!n->name) 2209 continue; 2210 2211 if (n->ino == parent->i_ino && 2212 !audit_compare_dname_path(dname, n->name, &dirlen)) { 2213 n->name_len = dirlen; /* update parent data in place */ 2214 found_parent = n->name; 2215 goto add_names; 2216 } 2217 } 2218 2219 /* no matching parent, look for matching child */ 2220 list_for_each_entry(n, &context->names_list, list) { 2221 if (!n->name) 2222 continue; 2223 2224 /* strcmp() is the more likely scenario */ 2225 if (!strcmp(dname, n->name) || 2226 !audit_compare_dname_path(dname, n->name, &dirlen)) { 2227 if (inode) 2228 audit_copy_inode(n, NULL, inode); 2229 else 2230 n->ino = (unsigned long)-1; 2231 found_child = n->name; 2232 goto add_names; 2233 } 2234 } 2235 2236 add_names: 2237 if (!found_parent) { 2238 n = audit_alloc_name(context); 2239 if (!n) 2240 return; 2241 audit_copy_inode(n, NULL, parent); 2242 } 2243 2244 if (!found_child) { 2245 n = audit_alloc_name(context); 2246 if (!n) 2247 return; 2248 2249 /* Re-use the name belonging to the slot for a matching parent 2250 * directory. All names for this context are relinquished in 2251 * audit_free_names() */ 2252 if (found_parent) { 2253 n->name = found_parent; 2254 n->name_len = AUDIT_NAME_FULL; 2255 /* don't call __putname() */ 2256 n->name_put = false; 2257 } 2258 2259 if (inode) 2260 audit_copy_inode(n, NULL, inode); 2261 } 2262 } 2263 EXPORT_SYMBOL_GPL(__audit_inode_child); 2264 2265 /** 2266 * auditsc_get_stamp - get local copies of audit_context values 2267 * @ctx: audit_context for the task 2268 * @t: timespec to store time recorded in the audit_context 2269 * @serial: serial value that is recorded in the audit_context 2270 * 2271 * Also sets the context as auditable. 2272 */ 2273 int auditsc_get_stamp(struct audit_context *ctx, 2274 struct timespec *t, unsigned int *serial) 2275 { 2276 if (!ctx->in_syscall) 2277 return 0; 2278 if (!ctx->serial) 2279 ctx->serial = audit_serial(); 2280 t->tv_sec = ctx->ctime.tv_sec; 2281 t->tv_nsec = ctx->ctime.tv_nsec; 2282 *serial = ctx->serial; 2283 if (!ctx->prio) { 2284 ctx->prio = 1; 2285 ctx->current_state = AUDIT_RECORD_CONTEXT; 2286 } 2287 return 1; 2288 } 2289 2290 /* global counter which is incremented every time something logs in */ 2291 static atomic_t session_id = ATOMIC_INIT(0); 2292 2293 /** 2294 * audit_set_loginuid - set current task's audit_context loginuid 2295 * @loginuid: loginuid value 2296 * 2297 * Returns 0. 2298 * 2299 * Called (set) from fs/proc/base.c::proc_loginuid_write(). 2300 */ 2301 int audit_set_loginuid(uid_t loginuid) 2302 { 2303 struct task_struct *task = current; 2304 struct audit_context *context = task->audit_context; 2305 unsigned int sessionid; 2306 2307 #ifdef CONFIG_AUDIT_LOGINUID_IMMUTABLE 2308 if (task->loginuid != -1) 2309 return -EPERM; 2310 #else /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */ 2311 if (!capable(CAP_AUDIT_CONTROL)) 2312 return -EPERM; 2313 #endif /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */ 2314 2315 sessionid = atomic_inc_return(&session_id); 2316 if (context && context->in_syscall) { 2317 struct audit_buffer *ab; 2318 2319 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); 2320 if (ab) { 2321 audit_log_format(ab, "login pid=%d uid=%u " 2322 "old auid=%u new auid=%u" 2323 " old ses=%u new ses=%u", 2324 task->pid, task_uid(task), 2325 task->loginuid, loginuid, 2326 task->sessionid, sessionid); 2327 audit_log_end(ab); 2328 } 2329 } 2330 task->sessionid = sessionid; 2331 task->loginuid = loginuid; 2332 return 0; 2333 } 2334 2335 /** 2336 * __audit_mq_open - record audit data for a POSIX MQ open 2337 * @oflag: open flag 2338 * @mode: mode bits 2339 * @attr: queue attributes 2340 * 2341 */ 2342 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr) 2343 { 2344 struct audit_context *context = current->audit_context; 2345 2346 if (attr) 2347 memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr)); 2348 else 2349 memset(&context->mq_open.attr, 0, sizeof(struct mq_attr)); 2350 2351 context->mq_open.oflag = oflag; 2352 context->mq_open.mode = mode; 2353 2354 context->type = AUDIT_MQ_OPEN; 2355 } 2356 2357 /** 2358 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive 2359 * @mqdes: MQ descriptor 2360 * @msg_len: Message length 2361 * @msg_prio: Message priority 2362 * @abs_timeout: Message timeout in absolute time 2363 * 2364 */ 2365 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, 2366 const struct timespec *abs_timeout) 2367 { 2368 struct audit_context *context = current->audit_context; 2369 struct timespec *p = &context->mq_sendrecv.abs_timeout; 2370 2371 if (abs_timeout) 2372 memcpy(p, abs_timeout, sizeof(struct timespec)); 2373 else 2374 memset(p, 0, sizeof(struct timespec)); 2375 2376 context->mq_sendrecv.mqdes = mqdes; 2377 context->mq_sendrecv.msg_len = msg_len; 2378 context->mq_sendrecv.msg_prio = msg_prio; 2379 2380 context->type = AUDIT_MQ_SENDRECV; 2381 } 2382 2383 /** 2384 * __audit_mq_notify - record audit data for a POSIX MQ notify 2385 * @mqdes: MQ descriptor 2386 * @notification: Notification event 2387 * 2388 */ 2389 2390 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification) 2391 { 2392 struct audit_context *context = current->audit_context; 2393 2394 if (notification) 2395 context->mq_notify.sigev_signo = notification->sigev_signo; 2396 else 2397 context->mq_notify.sigev_signo = 0; 2398 2399 context->mq_notify.mqdes = mqdes; 2400 context->type = AUDIT_MQ_NOTIFY; 2401 } 2402 2403 /** 2404 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute 2405 * @mqdes: MQ descriptor 2406 * @mqstat: MQ flags 2407 * 2408 */ 2409 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) 2410 { 2411 struct audit_context *context = current->audit_context; 2412 context->mq_getsetattr.mqdes = mqdes; 2413 context->mq_getsetattr.mqstat = *mqstat; 2414 context->type = AUDIT_MQ_GETSETATTR; 2415 } 2416 2417 /** 2418 * audit_ipc_obj - record audit data for ipc object 2419 * @ipcp: ipc permissions 2420 * 2421 */ 2422 void __audit_ipc_obj(struct kern_ipc_perm *ipcp) 2423 { 2424 struct audit_context *context = current->audit_context; 2425 context->ipc.uid = ipcp->uid; 2426 context->ipc.gid = ipcp->gid; 2427 context->ipc.mode = ipcp->mode; 2428 context->ipc.has_perm = 0; 2429 security_ipc_getsecid(ipcp, &context->ipc.osid); 2430 context->type = AUDIT_IPC; 2431 } 2432 2433 /** 2434 * audit_ipc_set_perm - record audit data for new ipc permissions 2435 * @qbytes: msgq bytes 2436 * @uid: msgq user id 2437 * @gid: msgq group id 2438 * @mode: msgq mode (permissions) 2439 * 2440 * Called only after audit_ipc_obj(). 2441 */ 2442 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode) 2443 { 2444 struct audit_context *context = current->audit_context; 2445 2446 context->ipc.qbytes = qbytes; 2447 context->ipc.perm_uid = uid; 2448 context->ipc.perm_gid = gid; 2449 context->ipc.perm_mode = mode; 2450 context->ipc.has_perm = 1; 2451 } 2452 2453 int __audit_bprm(struct linux_binprm *bprm) 2454 { 2455 struct audit_aux_data_execve *ax; 2456 struct audit_context *context = current->audit_context; 2457 2458 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2459 if (!ax) 2460 return -ENOMEM; 2461 2462 ax->argc = bprm->argc; 2463 ax->envc = bprm->envc; 2464 ax->mm = bprm->mm; 2465 ax->d.type = AUDIT_EXECVE; 2466 ax->d.next = context->aux; 2467 context->aux = (void *)ax; 2468 return 0; 2469 } 2470 2471 2472 /** 2473 * audit_socketcall - record audit data for sys_socketcall 2474 * @nargs: number of args 2475 * @args: args array 2476 * 2477 */ 2478 void __audit_socketcall(int nargs, unsigned long *args) 2479 { 2480 struct audit_context *context = current->audit_context; 2481 2482 context->type = AUDIT_SOCKETCALL; 2483 context->socketcall.nargs = nargs; 2484 memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long)); 2485 } 2486 2487 /** 2488 * __audit_fd_pair - record audit data for pipe and socketpair 2489 * @fd1: the first file descriptor 2490 * @fd2: the second file descriptor 2491 * 2492 */ 2493 void __audit_fd_pair(int fd1, int fd2) 2494 { 2495 struct audit_context *context = current->audit_context; 2496 context->fds[0] = fd1; 2497 context->fds[1] = fd2; 2498 } 2499 2500 /** 2501 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto 2502 * @len: data length in user space 2503 * @a: data address in kernel space 2504 * 2505 * Returns 0 for success or NULL context or < 0 on error. 2506 */ 2507 int __audit_sockaddr(int len, void *a) 2508 { 2509 struct audit_context *context = current->audit_context; 2510 2511 if (!context->sockaddr) { 2512 void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL); 2513 if (!p) 2514 return -ENOMEM; 2515 context->sockaddr = p; 2516 } 2517 2518 context->sockaddr_len = len; 2519 memcpy(context->sockaddr, a, len); 2520 return 0; 2521 } 2522 2523 void __audit_ptrace(struct task_struct *t) 2524 { 2525 struct audit_context *context = current->audit_context; 2526 2527 context->target_pid = t->pid; 2528 context->target_auid = audit_get_loginuid(t); 2529 context->target_uid = task_uid(t); 2530 context->target_sessionid = audit_get_sessionid(t); 2531 security_task_getsecid(t, &context->target_sid); 2532 memcpy(context->target_comm, t->comm, TASK_COMM_LEN); 2533 } 2534 2535 /** 2536 * audit_signal_info - record signal info for shutting down audit subsystem 2537 * @sig: signal value 2538 * @t: task being signaled 2539 * 2540 * If the audit subsystem is being terminated, record the task (pid) 2541 * and uid that is doing that. 2542 */ 2543 int __audit_signal_info(int sig, struct task_struct *t) 2544 { 2545 struct audit_aux_data_pids *axp; 2546 struct task_struct *tsk = current; 2547 struct audit_context *ctx = tsk->audit_context; 2548 uid_t uid = current_uid(), t_uid = task_uid(t); 2549 2550 if (audit_pid && t->tgid == audit_pid) { 2551 if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) { 2552 audit_sig_pid = tsk->pid; 2553 if (tsk->loginuid != -1) 2554 audit_sig_uid = tsk->loginuid; 2555 else 2556 audit_sig_uid = uid; 2557 security_task_getsecid(tsk, &audit_sig_sid); 2558 } 2559 if (!audit_signals || audit_dummy_context()) 2560 return 0; 2561 } 2562 2563 /* optimize the common case by putting first signal recipient directly 2564 * in audit_context */ 2565 if (!ctx->target_pid) { 2566 ctx->target_pid = t->tgid; 2567 ctx->target_auid = audit_get_loginuid(t); 2568 ctx->target_uid = t_uid; 2569 ctx->target_sessionid = audit_get_sessionid(t); 2570 security_task_getsecid(t, &ctx->target_sid); 2571 memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); 2572 return 0; 2573 } 2574 2575 axp = (void *)ctx->aux_pids; 2576 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { 2577 axp = kzalloc(sizeof(*axp), GFP_ATOMIC); 2578 if (!axp) 2579 return -ENOMEM; 2580 2581 axp->d.type = AUDIT_OBJ_PID; 2582 axp->d.next = ctx->aux_pids; 2583 ctx->aux_pids = (void *)axp; 2584 } 2585 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); 2586 2587 axp->target_pid[axp->pid_count] = t->tgid; 2588 axp->target_auid[axp->pid_count] = audit_get_loginuid(t); 2589 axp->target_uid[axp->pid_count] = t_uid; 2590 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); 2591 security_task_getsecid(t, &axp->target_sid[axp->pid_count]); 2592 memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); 2593 axp->pid_count++; 2594 2595 return 0; 2596 } 2597 2598 /** 2599 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps 2600 * @bprm: pointer to the bprm being processed 2601 * @new: the proposed new credentials 2602 * @old: the old credentials 2603 * 2604 * Simply check if the proc already has the caps given by the file and if not 2605 * store the priv escalation info for later auditing at the end of the syscall 2606 * 2607 * -Eric 2608 */ 2609 int __audit_log_bprm_fcaps(struct linux_binprm *bprm, 2610 const struct cred *new, const struct cred *old) 2611 { 2612 struct audit_aux_data_bprm_fcaps *ax; 2613 struct audit_context *context = current->audit_context; 2614 struct cpu_vfs_cap_data vcaps; 2615 struct dentry *dentry; 2616 2617 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2618 if (!ax) 2619 return -ENOMEM; 2620 2621 ax->d.type = AUDIT_BPRM_FCAPS; 2622 ax->d.next = context->aux; 2623 context->aux = (void *)ax; 2624 2625 dentry = dget(bprm->file->f_dentry); 2626 get_vfs_caps_from_disk(dentry, &vcaps); 2627 dput(dentry); 2628 2629 ax->fcap.permitted = vcaps.permitted; 2630 ax->fcap.inheritable = vcaps.inheritable; 2631 ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 2632 ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; 2633 2634 ax->old_pcap.permitted = old->cap_permitted; 2635 ax->old_pcap.inheritable = old->cap_inheritable; 2636 ax->old_pcap.effective = old->cap_effective; 2637 2638 ax->new_pcap.permitted = new->cap_permitted; 2639 ax->new_pcap.inheritable = new->cap_inheritable; 2640 ax->new_pcap.effective = new->cap_effective; 2641 return 0; 2642 } 2643 2644 /** 2645 * __audit_log_capset - store information about the arguments to the capset syscall 2646 * @pid: target pid of the capset call 2647 * @new: the new credentials 2648 * @old: the old (current) credentials 2649 * 2650 * Record the aguments userspace sent to sys_capset for later printing by the 2651 * audit system if applicable 2652 */ 2653 void __audit_log_capset(pid_t pid, 2654 const struct cred *new, const struct cred *old) 2655 { 2656 struct audit_context *context = current->audit_context; 2657 context->capset.pid = pid; 2658 context->capset.cap.effective = new->cap_effective; 2659 context->capset.cap.inheritable = new->cap_effective; 2660 context->capset.cap.permitted = new->cap_permitted; 2661 context->type = AUDIT_CAPSET; 2662 } 2663 2664 void __audit_mmap_fd(int fd, int flags) 2665 { 2666 struct audit_context *context = current->audit_context; 2667 context->mmap.fd = fd; 2668 context->mmap.flags = flags; 2669 context->type = AUDIT_MMAP; 2670 } 2671 2672 static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr) 2673 { 2674 uid_t auid, uid; 2675 gid_t gid; 2676 unsigned int sessionid; 2677 2678 auid = audit_get_loginuid(current); 2679 sessionid = audit_get_sessionid(current); 2680 current_uid_gid(&uid, &gid); 2681 2682 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", 2683 auid, uid, gid, sessionid); 2684 audit_log_task_context(ab); 2685 audit_log_format(ab, " pid=%d comm=", current->pid); 2686 audit_log_untrustedstring(ab, current->comm); 2687 audit_log_format(ab, " reason="); 2688 audit_log_string(ab, reason); 2689 audit_log_format(ab, " sig=%ld", signr); 2690 } 2691 /** 2692 * audit_core_dumps - record information about processes that end abnormally 2693 * @signr: signal value 2694 * 2695 * If a process ends with a core dump, something fishy is going on and we 2696 * should record the event for investigation. 2697 */ 2698 void audit_core_dumps(long signr) 2699 { 2700 struct audit_buffer *ab; 2701 2702 if (!audit_enabled) 2703 return; 2704 2705 if (signr == SIGQUIT) /* don't care for those */ 2706 return; 2707 2708 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); 2709 audit_log_abend(ab, "memory violation", signr); 2710 audit_log_end(ab); 2711 } 2712 2713 void __audit_seccomp(unsigned long syscall) 2714 { 2715 struct audit_buffer *ab; 2716 2717 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); 2718 audit_log_abend(ab, "seccomp", SIGKILL); 2719 audit_log_format(ab, " syscall=%ld", syscall); 2720 audit_log_end(ab); 2721 } 2722 2723 struct list_head *audit_killed_trees(void) 2724 { 2725 struct audit_context *ctx = current->audit_context; 2726 if (likely(!ctx || !ctx->in_syscall)) 2727 return NULL; 2728 return &ctx->killed_trees; 2729 } 2730