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 #include <linux/compat.h> 71 72 #include "audit.h" 73 74 /* flags stating the success for a syscall */ 75 #define AUDITSC_INVALID 0 76 #define AUDITSC_SUCCESS 1 77 #define AUDITSC_FAILURE 2 78 79 /* AUDIT_NAMES is the number of slots we reserve in the audit_context 80 * for saving names from getname(). If we get more names we will allocate 81 * a name dynamically and also add those to the list anchored by names_list. */ 82 #define AUDIT_NAMES 5 83 84 /* Indicates that audit should log the full pathname. */ 85 #define AUDIT_NAME_FULL -1 86 87 /* no execve audit message should be longer than this (userspace limits) */ 88 #define MAX_EXECVE_AUDIT_LEN 7500 89 90 /* number of audit rules */ 91 int audit_n_rules; 92 93 /* determines whether we collect data for signals sent */ 94 int audit_signals; 95 96 struct audit_cap_data { 97 kernel_cap_t permitted; 98 kernel_cap_t inheritable; 99 union { 100 unsigned int fE; /* effective bit of a file capability */ 101 kernel_cap_t effective; /* effective set of a process */ 102 }; 103 }; 104 105 /* When fs/namei.c:getname() is called, we store the pointer in name and 106 * we don't let putname() free it (instead we free all of the saved 107 * pointers at syscall exit time). 108 * 109 * Further, in fs/namei.c:path_lookup() we store the inode and device. */ 110 struct audit_names { 111 struct list_head list; /* audit_context->names_list */ 112 const char *name; 113 unsigned long ino; 114 dev_t dev; 115 umode_t mode; 116 kuid_t uid; 117 kgid_t gid; 118 dev_t rdev; 119 u32 osid; 120 struct audit_cap_data fcap; 121 unsigned int fcap_ver; 122 int name_len; /* number of name's characters to log */ 123 bool name_put; /* call __putname() for this name */ 124 /* 125 * This was an allocated audit_names and not from the array of 126 * names allocated in the task audit context. Thus this name 127 * should be freed on syscall exit 128 */ 129 bool should_free; 130 }; 131 132 struct audit_aux_data { 133 struct audit_aux_data *next; 134 int type; 135 }; 136 137 #define AUDIT_AUX_IPCPERM 0 138 139 /* Number of target pids per aux struct. */ 140 #define AUDIT_AUX_PIDS 16 141 142 struct audit_aux_data_execve { 143 struct audit_aux_data d; 144 int argc; 145 int envc; 146 struct mm_struct *mm; 147 }; 148 149 struct audit_aux_data_pids { 150 struct audit_aux_data d; 151 pid_t target_pid[AUDIT_AUX_PIDS]; 152 kuid_t target_auid[AUDIT_AUX_PIDS]; 153 kuid_t target_uid[AUDIT_AUX_PIDS]; 154 unsigned int target_sessionid[AUDIT_AUX_PIDS]; 155 u32 target_sid[AUDIT_AUX_PIDS]; 156 char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN]; 157 int pid_count; 158 }; 159 160 struct audit_aux_data_bprm_fcaps { 161 struct audit_aux_data d; 162 struct audit_cap_data fcap; 163 unsigned int fcap_ver; 164 struct audit_cap_data old_pcap; 165 struct audit_cap_data new_pcap; 166 }; 167 168 struct audit_aux_data_capset { 169 struct audit_aux_data d; 170 pid_t pid; 171 struct audit_cap_data cap; 172 }; 173 174 struct audit_tree_refs { 175 struct audit_tree_refs *next; 176 struct audit_chunk *c[31]; 177 }; 178 179 /* The per-task audit context. */ 180 struct audit_context { 181 int dummy; /* must be the first element */ 182 int in_syscall; /* 1 if task is in a syscall */ 183 enum audit_state state, current_state; 184 unsigned int serial; /* serial number for record */ 185 int major; /* syscall number */ 186 struct timespec ctime; /* time of syscall entry */ 187 unsigned long argv[4]; /* syscall arguments */ 188 long return_code;/* syscall return code */ 189 u64 prio; 190 int return_valid; /* return code is valid */ 191 /* 192 * The names_list is the list of all audit_names collected during this 193 * syscall. The first AUDIT_NAMES entries in the names_list will 194 * actually be from the preallocated_names array for performance 195 * reasons. Except during allocation they should never be referenced 196 * through the preallocated_names array and should only be found/used 197 * by running the names_list. 198 */ 199 struct audit_names preallocated_names[AUDIT_NAMES]; 200 int name_count; /* total records in names_list */ 201 struct list_head names_list; /* anchor for struct audit_names->list */ 202 char * filterkey; /* key for rule that triggered record */ 203 struct path pwd; 204 struct audit_context *previous; /* For nested syscalls */ 205 struct audit_aux_data *aux; 206 struct audit_aux_data *aux_pids; 207 struct sockaddr_storage *sockaddr; 208 size_t sockaddr_len; 209 /* Save things to print about task_struct */ 210 pid_t pid, ppid; 211 kuid_t uid, euid, suid, fsuid; 212 kgid_t gid, egid, sgid, fsgid; 213 unsigned long personality; 214 int arch; 215 216 pid_t target_pid; 217 kuid_t target_auid; 218 kuid_t target_uid; 219 unsigned int target_sessionid; 220 u32 target_sid; 221 char target_comm[TASK_COMM_LEN]; 222 223 struct audit_tree_refs *trees, *first_trees; 224 struct list_head killed_trees; 225 int tree_count; 226 227 int type; 228 union { 229 struct { 230 int nargs; 231 long args[6]; 232 } socketcall; 233 struct { 234 kuid_t uid; 235 kgid_t gid; 236 umode_t mode; 237 u32 osid; 238 int has_perm; 239 uid_t perm_uid; 240 gid_t perm_gid; 241 umode_t perm_mode; 242 unsigned long qbytes; 243 } ipc; 244 struct { 245 mqd_t mqdes; 246 struct mq_attr mqstat; 247 } mq_getsetattr; 248 struct { 249 mqd_t mqdes; 250 int sigev_signo; 251 } mq_notify; 252 struct { 253 mqd_t mqdes; 254 size_t msg_len; 255 unsigned int msg_prio; 256 struct timespec abs_timeout; 257 } mq_sendrecv; 258 struct { 259 int oflag; 260 umode_t mode; 261 struct mq_attr attr; 262 } mq_open; 263 struct { 264 pid_t pid; 265 struct audit_cap_data cap; 266 } capset; 267 struct { 268 int fd; 269 int flags; 270 } mmap; 271 }; 272 int fds[2]; 273 274 #if AUDIT_DEBUG 275 int put_count; 276 int ino_count; 277 #endif 278 }; 279 280 static inline int open_arg(int flags, int mask) 281 { 282 int n = ACC_MODE(flags); 283 if (flags & (O_TRUNC | O_CREAT)) 284 n |= AUDIT_PERM_WRITE; 285 return n & mask; 286 } 287 288 static int audit_match_perm(struct audit_context *ctx, int mask) 289 { 290 unsigned n; 291 if (unlikely(!ctx)) 292 return 0; 293 n = ctx->major; 294 295 switch (audit_classify_syscall(ctx->arch, n)) { 296 case 0: /* native */ 297 if ((mask & AUDIT_PERM_WRITE) && 298 audit_match_class(AUDIT_CLASS_WRITE, n)) 299 return 1; 300 if ((mask & AUDIT_PERM_READ) && 301 audit_match_class(AUDIT_CLASS_READ, n)) 302 return 1; 303 if ((mask & AUDIT_PERM_ATTR) && 304 audit_match_class(AUDIT_CLASS_CHATTR, n)) 305 return 1; 306 return 0; 307 case 1: /* 32bit on biarch */ 308 if ((mask & AUDIT_PERM_WRITE) && 309 audit_match_class(AUDIT_CLASS_WRITE_32, n)) 310 return 1; 311 if ((mask & AUDIT_PERM_READ) && 312 audit_match_class(AUDIT_CLASS_READ_32, n)) 313 return 1; 314 if ((mask & AUDIT_PERM_ATTR) && 315 audit_match_class(AUDIT_CLASS_CHATTR_32, n)) 316 return 1; 317 return 0; 318 case 2: /* open */ 319 return mask & ACC_MODE(ctx->argv[1]); 320 case 3: /* openat */ 321 return mask & ACC_MODE(ctx->argv[2]); 322 case 4: /* socketcall */ 323 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); 324 case 5: /* execve */ 325 return mask & AUDIT_PERM_EXEC; 326 default: 327 return 0; 328 } 329 } 330 331 static int audit_match_filetype(struct audit_context *ctx, int val) 332 { 333 struct audit_names *n; 334 umode_t mode = (umode_t)val; 335 336 if (unlikely(!ctx)) 337 return 0; 338 339 list_for_each_entry(n, &ctx->names_list, list) { 340 if ((n->ino != -1) && 341 ((n->mode & S_IFMT) == mode)) 342 return 1; 343 } 344 345 return 0; 346 } 347 348 /* 349 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *; 350 * ->first_trees points to its beginning, ->trees - to the current end of data. 351 * ->tree_count is the number of free entries in array pointed to by ->trees. 352 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL, 353 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously, 354 * it's going to remain 1-element for almost any setup) until we free context itself. 355 * References in it _are_ dropped - at the same time we free/drop aux stuff. 356 */ 357 358 #ifdef CONFIG_AUDIT_TREE 359 static void audit_set_auditable(struct audit_context *ctx) 360 { 361 if (!ctx->prio) { 362 ctx->prio = 1; 363 ctx->current_state = AUDIT_RECORD_CONTEXT; 364 } 365 } 366 367 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk) 368 { 369 struct audit_tree_refs *p = ctx->trees; 370 int left = ctx->tree_count; 371 if (likely(left)) { 372 p->c[--left] = chunk; 373 ctx->tree_count = left; 374 return 1; 375 } 376 if (!p) 377 return 0; 378 p = p->next; 379 if (p) { 380 p->c[30] = chunk; 381 ctx->trees = p; 382 ctx->tree_count = 30; 383 return 1; 384 } 385 return 0; 386 } 387 388 static int grow_tree_refs(struct audit_context *ctx) 389 { 390 struct audit_tree_refs *p = ctx->trees; 391 ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL); 392 if (!ctx->trees) { 393 ctx->trees = p; 394 return 0; 395 } 396 if (p) 397 p->next = ctx->trees; 398 else 399 ctx->first_trees = ctx->trees; 400 ctx->tree_count = 31; 401 return 1; 402 } 403 #endif 404 405 static void unroll_tree_refs(struct audit_context *ctx, 406 struct audit_tree_refs *p, int count) 407 { 408 #ifdef CONFIG_AUDIT_TREE 409 struct audit_tree_refs *q; 410 int n; 411 if (!p) { 412 /* we started with empty chain */ 413 p = ctx->first_trees; 414 count = 31; 415 /* if the very first allocation has failed, nothing to do */ 416 if (!p) 417 return; 418 } 419 n = count; 420 for (q = p; q != ctx->trees; q = q->next, n = 31) { 421 while (n--) { 422 audit_put_chunk(q->c[n]); 423 q->c[n] = NULL; 424 } 425 } 426 while (n-- > ctx->tree_count) { 427 audit_put_chunk(q->c[n]); 428 q->c[n] = NULL; 429 } 430 ctx->trees = p; 431 ctx->tree_count = count; 432 #endif 433 } 434 435 static void free_tree_refs(struct audit_context *ctx) 436 { 437 struct audit_tree_refs *p, *q; 438 for (p = ctx->first_trees; p; p = q) { 439 q = p->next; 440 kfree(p); 441 } 442 } 443 444 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree) 445 { 446 #ifdef CONFIG_AUDIT_TREE 447 struct audit_tree_refs *p; 448 int n; 449 if (!tree) 450 return 0; 451 /* full ones */ 452 for (p = ctx->first_trees; p != ctx->trees; p = p->next) { 453 for (n = 0; n < 31; n++) 454 if (audit_tree_match(p->c[n], tree)) 455 return 1; 456 } 457 /* partial */ 458 if (p) { 459 for (n = ctx->tree_count; n < 31; n++) 460 if (audit_tree_match(p->c[n], tree)) 461 return 1; 462 } 463 #endif 464 return 0; 465 } 466 467 static int audit_compare_uid(kuid_t uid, 468 struct audit_names *name, 469 struct audit_field *f, 470 struct audit_context *ctx) 471 { 472 struct audit_names *n; 473 int rc; 474 475 if (name) { 476 rc = audit_uid_comparator(uid, f->op, name->uid); 477 if (rc) 478 return rc; 479 } 480 481 if (ctx) { 482 list_for_each_entry(n, &ctx->names_list, list) { 483 rc = audit_uid_comparator(uid, f->op, n->uid); 484 if (rc) 485 return rc; 486 } 487 } 488 return 0; 489 } 490 491 static int audit_compare_gid(kgid_t gid, 492 struct audit_names *name, 493 struct audit_field *f, 494 struct audit_context *ctx) 495 { 496 struct audit_names *n; 497 int rc; 498 499 if (name) { 500 rc = audit_gid_comparator(gid, f->op, name->gid); 501 if (rc) 502 return rc; 503 } 504 505 if (ctx) { 506 list_for_each_entry(n, &ctx->names_list, list) { 507 rc = audit_gid_comparator(gid, f->op, n->gid); 508 if (rc) 509 return rc; 510 } 511 } 512 return 0; 513 } 514 515 static int audit_field_compare(struct task_struct *tsk, 516 const struct cred *cred, 517 struct audit_field *f, 518 struct audit_context *ctx, 519 struct audit_names *name) 520 { 521 switch (f->val) { 522 /* process to file object comparisons */ 523 case AUDIT_COMPARE_UID_TO_OBJ_UID: 524 return audit_compare_uid(cred->uid, name, f, ctx); 525 case AUDIT_COMPARE_GID_TO_OBJ_GID: 526 return audit_compare_gid(cred->gid, name, f, ctx); 527 case AUDIT_COMPARE_EUID_TO_OBJ_UID: 528 return audit_compare_uid(cred->euid, name, f, ctx); 529 case AUDIT_COMPARE_EGID_TO_OBJ_GID: 530 return audit_compare_gid(cred->egid, name, f, ctx); 531 case AUDIT_COMPARE_AUID_TO_OBJ_UID: 532 return audit_compare_uid(tsk->loginuid, name, f, ctx); 533 case AUDIT_COMPARE_SUID_TO_OBJ_UID: 534 return audit_compare_uid(cred->suid, name, f, ctx); 535 case AUDIT_COMPARE_SGID_TO_OBJ_GID: 536 return audit_compare_gid(cred->sgid, name, f, ctx); 537 case AUDIT_COMPARE_FSUID_TO_OBJ_UID: 538 return audit_compare_uid(cred->fsuid, name, f, ctx); 539 case AUDIT_COMPARE_FSGID_TO_OBJ_GID: 540 return audit_compare_gid(cred->fsgid, name, f, ctx); 541 /* uid comparisons */ 542 case AUDIT_COMPARE_UID_TO_AUID: 543 return audit_uid_comparator(cred->uid, f->op, tsk->loginuid); 544 case AUDIT_COMPARE_UID_TO_EUID: 545 return audit_uid_comparator(cred->uid, f->op, cred->euid); 546 case AUDIT_COMPARE_UID_TO_SUID: 547 return audit_uid_comparator(cred->uid, f->op, cred->suid); 548 case AUDIT_COMPARE_UID_TO_FSUID: 549 return audit_uid_comparator(cred->uid, f->op, cred->fsuid); 550 /* auid comparisons */ 551 case AUDIT_COMPARE_AUID_TO_EUID: 552 return audit_uid_comparator(tsk->loginuid, f->op, cred->euid); 553 case AUDIT_COMPARE_AUID_TO_SUID: 554 return audit_uid_comparator(tsk->loginuid, f->op, cred->suid); 555 case AUDIT_COMPARE_AUID_TO_FSUID: 556 return audit_uid_comparator(tsk->loginuid, f->op, cred->fsuid); 557 /* euid comparisons */ 558 case AUDIT_COMPARE_EUID_TO_SUID: 559 return audit_uid_comparator(cred->euid, f->op, cred->suid); 560 case AUDIT_COMPARE_EUID_TO_FSUID: 561 return audit_uid_comparator(cred->euid, f->op, cred->fsuid); 562 /* suid comparisons */ 563 case AUDIT_COMPARE_SUID_TO_FSUID: 564 return audit_uid_comparator(cred->suid, f->op, cred->fsuid); 565 /* gid comparisons */ 566 case AUDIT_COMPARE_GID_TO_EGID: 567 return audit_gid_comparator(cred->gid, f->op, cred->egid); 568 case AUDIT_COMPARE_GID_TO_SGID: 569 return audit_gid_comparator(cred->gid, f->op, cred->sgid); 570 case AUDIT_COMPARE_GID_TO_FSGID: 571 return audit_gid_comparator(cred->gid, f->op, cred->fsgid); 572 /* egid comparisons */ 573 case AUDIT_COMPARE_EGID_TO_SGID: 574 return audit_gid_comparator(cred->egid, f->op, cred->sgid); 575 case AUDIT_COMPARE_EGID_TO_FSGID: 576 return audit_gid_comparator(cred->egid, f->op, cred->fsgid); 577 /* sgid comparison */ 578 case AUDIT_COMPARE_SGID_TO_FSGID: 579 return audit_gid_comparator(cred->sgid, f->op, cred->fsgid); 580 default: 581 WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n"); 582 return 0; 583 } 584 return 0; 585 } 586 587 /* Determine if any context name data matches a rule's watch data */ 588 /* Compare a task_struct with an audit_rule. Return 1 on match, 0 589 * otherwise. 590 * 591 * If task_creation is true, this is an explicit indication that we are 592 * filtering a task rule at task creation time. This and tsk == current are 593 * the only situations where tsk->cred may be accessed without an rcu read lock. 594 */ 595 static int audit_filter_rules(struct task_struct *tsk, 596 struct audit_krule *rule, 597 struct audit_context *ctx, 598 struct audit_names *name, 599 enum audit_state *state, 600 bool task_creation) 601 { 602 const struct cred *cred; 603 int i, need_sid = 1; 604 u32 sid; 605 606 cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation); 607 608 for (i = 0; i < rule->field_count; i++) { 609 struct audit_field *f = &rule->fields[i]; 610 struct audit_names *n; 611 int result = 0; 612 613 switch (f->type) { 614 case AUDIT_PID: 615 result = audit_comparator(tsk->pid, f->op, f->val); 616 break; 617 case AUDIT_PPID: 618 if (ctx) { 619 if (!ctx->ppid) 620 ctx->ppid = sys_getppid(); 621 result = audit_comparator(ctx->ppid, f->op, f->val); 622 } 623 break; 624 case AUDIT_UID: 625 result = audit_uid_comparator(cred->uid, f->op, f->uid); 626 break; 627 case AUDIT_EUID: 628 result = audit_uid_comparator(cred->euid, f->op, f->uid); 629 break; 630 case AUDIT_SUID: 631 result = audit_uid_comparator(cred->suid, f->op, f->uid); 632 break; 633 case AUDIT_FSUID: 634 result = audit_uid_comparator(cred->fsuid, f->op, f->uid); 635 break; 636 case AUDIT_GID: 637 result = audit_gid_comparator(cred->gid, f->op, f->gid); 638 break; 639 case AUDIT_EGID: 640 result = audit_gid_comparator(cred->egid, f->op, f->gid); 641 break; 642 case AUDIT_SGID: 643 result = audit_gid_comparator(cred->sgid, f->op, f->gid); 644 break; 645 case AUDIT_FSGID: 646 result = audit_gid_comparator(cred->fsgid, f->op, f->gid); 647 break; 648 case AUDIT_PERS: 649 result = audit_comparator(tsk->personality, f->op, f->val); 650 break; 651 case AUDIT_ARCH: 652 if (ctx) 653 result = audit_comparator(ctx->arch, f->op, f->val); 654 break; 655 656 case AUDIT_EXIT: 657 if (ctx && ctx->return_valid) 658 result = audit_comparator(ctx->return_code, f->op, f->val); 659 break; 660 case AUDIT_SUCCESS: 661 if (ctx && ctx->return_valid) { 662 if (f->val) 663 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS); 664 else 665 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE); 666 } 667 break; 668 case AUDIT_DEVMAJOR: 669 if (name) { 670 if (audit_comparator(MAJOR(name->dev), f->op, f->val) || 671 audit_comparator(MAJOR(name->rdev), f->op, f->val)) 672 ++result; 673 } else if (ctx) { 674 list_for_each_entry(n, &ctx->names_list, list) { 675 if (audit_comparator(MAJOR(n->dev), f->op, f->val) || 676 audit_comparator(MAJOR(n->rdev), f->op, f->val)) { 677 ++result; 678 break; 679 } 680 } 681 } 682 break; 683 case AUDIT_DEVMINOR: 684 if (name) { 685 if (audit_comparator(MINOR(name->dev), f->op, f->val) || 686 audit_comparator(MINOR(name->rdev), f->op, f->val)) 687 ++result; 688 } else if (ctx) { 689 list_for_each_entry(n, &ctx->names_list, list) { 690 if (audit_comparator(MINOR(n->dev), f->op, f->val) || 691 audit_comparator(MINOR(n->rdev), f->op, f->val)) { 692 ++result; 693 break; 694 } 695 } 696 } 697 break; 698 case AUDIT_INODE: 699 if (name) 700 result = (name->ino == f->val); 701 else if (ctx) { 702 list_for_each_entry(n, &ctx->names_list, list) { 703 if (audit_comparator(n->ino, f->op, f->val)) { 704 ++result; 705 break; 706 } 707 } 708 } 709 break; 710 case AUDIT_OBJ_UID: 711 if (name) { 712 result = audit_uid_comparator(name->uid, f->op, f->uid); 713 } else if (ctx) { 714 list_for_each_entry(n, &ctx->names_list, list) { 715 if (audit_uid_comparator(n->uid, f->op, f->uid)) { 716 ++result; 717 break; 718 } 719 } 720 } 721 break; 722 case AUDIT_OBJ_GID: 723 if (name) { 724 result = audit_gid_comparator(name->gid, f->op, f->gid); 725 } else if (ctx) { 726 list_for_each_entry(n, &ctx->names_list, list) { 727 if (audit_gid_comparator(n->gid, f->op, f->gid)) { 728 ++result; 729 break; 730 } 731 } 732 } 733 break; 734 case AUDIT_WATCH: 735 if (name) 736 result = audit_watch_compare(rule->watch, name->ino, name->dev); 737 break; 738 case AUDIT_DIR: 739 if (ctx) 740 result = match_tree_refs(ctx, rule->tree); 741 break; 742 case AUDIT_LOGINUID: 743 result = 0; 744 if (ctx) 745 result = audit_uid_comparator(tsk->loginuid, f->op, f->uid); 746 break; 747 case AUDIT_SUBJ_USER: 748 case AUDIT_SUBJ_ROLE: 749 case AUDIT_SUBJ_TYPE: 750 case AUDIT_SUBJ_SEN: 751 case AUDIT_SUBJ_CLR: 752 /* NOTE: this may return negative values indicating 753 a temporary error. We simply treat this as a 754 match for now to avoid losing information that 755 may be wanted. An error message will also be 756 logged upon error */ 757 if (f->lsm_rule) { 758 if (need_sid) { 759 security_task_getsecid(tsk, &sid); 760 need_sid = 0; 761 } 762 result = security_audit_rule_match(sid, f->type, 763 f->op, 764 f->lsm_rule, 765 ctx); 766 } 767 break; 768 case AUDIT_OBJ_USER: 769 case AUDIT_OBJ_ROLE: 770 case AUDIT_OBJ_TYPE: 771 case AUDIT_OBJ_LEV_LOW: 772 case AUDIT_OBJ_LEV_HIGH: 773 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR 774 also applies here */ 775 if (f->lsm_rule) { 776 /* Find files that match */ 777 if (name) { 778 result = security_audit_rule_match( 779 name->osid, f->type, f->op, 780 f->lsm_rule, ctx); 781 } else if (ctx) { 782 list_for_each_entry(n, &ctx->names_list, list) { 783 if (security_audit_rule_match(n->osid, f->type, 784 f->op, f->lsm_rule, 785 ctx)) { 786 ++result; 787 break; 788 } 789 } 790 } 791 /* Find ipc objects that match */ 792 if (!ctx || ctx->type != AUDIT_IPC) 793 break; 794 if (security_audit_rule_match(ctx->ipc.osid, 795 f->type, f->op, 796 f->lsm_rule, ctx)) 797 ++result; 798 } 799 break; 800 case AUDIT_ARG0: 801 case AUDIT_ARG1: 802 case AUDIT_ARG2: 803 case AUDIT_ARG3: 804 if (ctx) 805 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val); 806 break; 807 case AUDIT_FILTERKEY: 808 /* ignore this field for filtering */ 809 result = 1; 810 break; 811 case AUDIT_PERM: 812 result = audit_match_perm(ctx, f->val); 813 break; 814 case AUDIT_FILETYPE: 815 result = audit_match_filetype(ctx, f->val); 816 break; 817 case AUDIT_FIELD_COMPARE: 818 result = audit_field_compare(tsk, cred, f, ctx, name); 819 break; 820 } 821 if (!result) 822 return 0; 823 } 824 825 if (ctx) { 826 if (rule->prio <= ctx->prio) 827 return 0; 828 if (rule->filterkey) { 829 kfree(ctx->filterkey); 830 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC); 831 } 832 ctx->prio = rule->prio; 833 } 834 switch (rule->action) { 835 case AUDIT_NEVER: *state = AUDIT_DISABLED; break; 836 case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; 837 } 838 return 1; 839 } 840 841 /* At process creation time, we can determine if system-call auditing is 842 * completely disabled for this task. Since we only have the task 843 * structure at this point, we can only check uid and gid. 844 */ 845 static enum audit_state audit_filter_task(struct task_struct *tsk, char **key) 846 { 847 struct audit_entry *e; 848 enum audit_state state; 849 850 rcu_read_lock(); 851 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { 852 if (audit_filter_rules(tsk, &e->rule, NULL, NULL, 853 &state, true)) { 854 if (state == AUDIT_RECORD_CONTEXT) 855 *key = kstrdup(e->rule.filterkey, GFP_ATOMIC); 856 rcu_read_unlock(); 857 return state; 858 } 859 } 860 rcu_read_unlock(); 861 return AUDIT_BUILD_CONTEXT; 862 } 863 864 /* At syscall entry and exit time, this filter is called if the 865 * audit_state is not low enough that auditing cannot take place, but is 866 * also not high enough that we already know we have to write an audit 867 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). 868 */ 869 static enum audit_state audit_filter_syscall(struct task_struct *tsk, 870 struct audit_context *ctx, 871 struct list_head *list) 872 { 873 struct audit_entry *e; 874 enum audit_state state; 875 876 if (audit_pid && tsk->tgid == audit_pid) 877 return AUDIT_DISABLED; 878 879 rcu_read_lock(); 880 if (!list_empty(list)) { 881 int word = AUDIT_WORD(ctx->major); 882 int bit = AUDIT_BIT(ctx->major); 883 884 list_for_each_entry_rcu(e, list, list) { 885 if ((e->rule.mask[word] & bit) == bit && 886 audit_filter_rules(tsk, &e->rule, ctx, NULL, 887 &state, false)) { 888 rcu_read_unlock(); 889 ctx->current_state = state; 890 return state; 891 } 892 } 893 } 894 rcu_read_unlock(); 895 return AUDIT_BUILD_CONTEXT; 896 } 897 898 /* 899 * Given an audit_name check the inode hash table to see if they match. 900 * Called holding the rcu read lock to protect the use of audit_inode_hash 901 */ 902 static int audit_filter_inode_name(struct task_struct *tsk, 903 struct audit_names *n, 904 struct audit_context *ctx) { 905 int word, bit; 906 int h = audit_hash_ino((u32)n->ino); 907 struct list_head *list = &audit_inode_hash[h]; 908 struct audit_entry *e; 909 enum audit_state state; 910 911 word = AUDIT_WORD(ctx->major); 912 bit = AUDIT_BIT(ctx->major); 913 914 if (list_empty(list)) 915 return 0; 916 917 list_for_each_entry_rcu(e, list, list) { 918 if ((e->rule.mask[word] & bit) == bit && 919 audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) { 920 ctx->current_state = state; 921 return 1; 922 } 923 } 924 925 return 0; 926 } 927 928 /* At syscall exit time, this filter is called if any audit_names have been 929 * collected during syscall processing. We only check rules in sublists at hash 930 * buckets applicable to the inode numbers in audit_names. 931 * Regarding audit_state, same rules apply as for audit_filter_syscall(). 932 */ 933 void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx) 934 { 935 struct audit_names *n; 936 937 if (audit_pid && tsk->tgid == audit_pid) 938 return; 939 940 rcu_read_lock(); 941 942 list_for_each_entry(n, &ctx->names_list, list) { 943 if (audit_filter_inode_name(tsk, n, ctx)) 944 break; 945 } 946 rcu_read_unlock(); 947 } 948 949 static inline struct audit_context *audit_get_context(struct task_struct *tsk, 950 int return_valid, 951 long return_code) 952 { 953 struct audit_context *context = tsk->audit_context; 954 955 if (!context) 956 return NULL; 957 context->return_valid = return_valid; 958 959 /* 960 * we need to fix up the return code in the audit logs if the actual 961 * return codes are later going to be fixed up by the arch specific 962 * signal handlers 963 * 964 * This is actually a test for: 965 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) || 966 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK) 967 * 968 * but is faster than a bunch of || 969 */ 970 if (unlikely(return_code <= -ERESTARTSYS) && 971 (return_code >= -ERESTART_RESTARTBLOCK) && 972 (return_code != -ENOIOCTLCMD)) 973 context->return_code = -EINTR; 974 else 975 context->return_code = return_code; 976 977 if (context->in_syscall && !context->dummy) { 978 audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]); 979 audit_filter_inodes(tsk, context); 980 } 981 982 tsk->audit_context = NULL; 983 return context; 984 } 985 986 static inline void audit_free_names(struct audit_context *context) 987 { 988 struct audit_names *n, *next; 989 990 #if AUDIT_DEBUG == 2 991 if (context->put_count + context->ino_count != context->name_count) { 992 printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d" 993 " name_count=%d put_count=%d" 994 " ino_count=%d [NOT freeing]\n", 995 __FILE__, __LINE__, 996 context->serial, context->major, context->in_syscall, 997 context->name_count, context->put_count, 998 context->ino_count); 999 list_for_each_entry(n, &context->names_list, list) { 1000 printk(KERN_ERR "names[%d] = %p = %s\n", i, 1001 n->name, n->name ?: "(null)"); 1002 } 1003 dump_stack(); 1004 return; 1005 } 1006 #endif 1007 #if AUDIT_DEBUG 1008 context->put_count = 0; 1009 context->ino_count = 0; 1010 #endif 1011 1012 list_for_each_entry_safe(n, next, &context->names_list, list) { 1013 list_del(&n->list); 1014 if (n->name && n->name_put) 1015 __putname(n->name); 1016 if (n->should_free) 1017 kfree(n); 1018 } 1019 context->name_count = 0; 1020 path_put(&context->pwd); 1021 context->pwd.dentry = NULL; 1022 context->pwd.mnt = NULL; 1023 } 1024 1025 static inline void audit_free_aux(struct audit_context *context) 1026 { 1027 struct audit_aux_data *aux; 1028 1029 while ((aux = context->aux)) { 1030 context->aux = aux->next; 1031 kfree(aux); 1032 } 1033 while ((aux = context->aux_pids)) { 1034 context->aux_pids = aux->next; 1035 kfree(aux); 1036 } 1037 } 1038 1039 static inline void audit_zero_context(struct audit_context *context, 1040 enum audit_state state) 1041 { 1042 memset(context, 0, sizeof(*context)); 1043 context->state = state; 1044 context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 1045 } 1046 1047 static inline struct audit_context *audit_alloc_context(enum audit_state state) 1048 { 1049 struct audit_context *context; 1050 1051 if (!(context = kmalloc(sizeof(*context), GFP_KERNEL))) 1052 return NULL; 1053 audit_zero_context(context, state); 1054 INIT_LIST_HEAD(&context->killed_trees); 1055 INIT_LIST_HEAD(&context->names_list); 1056 return context; 1057 } 1058 1059 /** 1060 * audit_alloc - allocate an audit context block for a task 1061 * @tsk: task 1062 * 1063 * Filter on the task information and allocate a per-task audit context 1064 * if necessary. Doing so turns on system call auditing for the 1065 * specified task. This is called from copy_process, so no lock is 1066 * needed. 1067 */ 1068 int audit_alloc(struct task_struct *tsk) 1069 { 1070 struct audit_context *context; 1071 enum audit_state state; 1072 char *key = NULL; 1073 1074 if (likely(!audit_ever_enabled)) 1075 return 0; /* Return if not auditing. */ 1076 1077 state = audit_filter_task(tsk, &key); 1078 if (state == AUDIT_DISABLED) 1079 return 0; 1080 1081 if (!(context = audit_alloc_context(state))) { 1082 kfree(key); 1083 audit_log_lost("out of memory in audit_alloc"); 1084 return -ENOMEM; 1085 } 1086 context->filterkey = key; 1087 1088 tsk->audit_context = context; 1089 set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); 1090 return 0; 1091 } 1092 1093 static inline void audit_free_context(struct audit_context *context) 1094 { 1095 struct audit_context *previous; 1096 int count = 0; 1097 1098 do { 1099 previous = context->previous; 1100 if (previous || (count && count < 10)) { 1101 ++count; 1102 printk(KERN_ERR "audit(:%d): major=%d name_count=%d:" 1103 " freeing multiple contexts (%d)\n", 1104 context->serial, context->major, 1105 context->name_count, count); 1106 } 1107 audit_free_names(context); 1108 unroll_tree_refs(context, NULL, 0); 1109 free_tree_refs(context); 1110 audit_free_aux(context); 1111 kfree(context->filterkey); 1112 kfree(context->sockaddr); 1113 kfree(context); 1114 context = previous; 1115 } while (context); 1116 if (count >= 10) 1117 printk(KERN_ERR "audit: freed %d contexts\n", count); 1118 } 1119 1120 void audit_log_task_context(struct audit_buffer *ab) 1121 { 1122 char *ctx = NULL; 1123 unsigned len; 1124 int error; 1125 u32 sid; 1126 1127 security_task_getsecid(current, &sid); 1128 if (!sid) 1129 return; 1130 1131 error = security_secid_to_secctx(sid, &ctx, &len); 1132 if (error) { 1133 if (error != -EINVAL) 1134 goto error_path; 1135 return; 1136 } 1137 1138 audit_log_format(ab, " subj=%s", ctx); 1139 security_release_secctx(ctx, len); 1140 return; 1141 1142 error_path: 1143 audit_panic("error in audit_log_task_context"); 1144 return; 1145 } 1146 1147 EXPORT_SYMBOL(audit_log_task_context); 1148 1149 void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk) 1150 { 1151 const struct cred *cred; 1152 char name[sizeof(tsk->comm)]; 1153 struct mm_struct *mm = tsk->mm; 1154 struct vm_area_struct *vma; 1155 char *tty; 1156 1157 if (!ab) 1158 return; 1159 1160 /* tsk == current */ 1161 cred = current_cred(); 1162 1163 spin_lock_irq(&tsk->sighand->siglock); 1164 if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name) 1165 tty = tsk->signal->tty->name; 1166 else 1167 tty = "(none)"; 1168 spin_unlock_irq(&tsk->sighand->siglock); 1169 1170 1171 audit_log_format(ab, 1172 " ppid=%ld pid=%d auid=%u uid=%u gid=%u" 1173 " euid=%u suid=%u fsuid=%u" 1174 " egid=%u sgid=%u fsgid=%u ses=%u tty=%s", 1175 sys_getppid(), 1176 tsk->pid, 1177 from_kuid(&init_user_ns, tsk->loginuid), 1178 from_kuid(&init_user_ns, cred->uid), 1179 from_kgid(&init_user_ns, cred->gid), 1180 from_kuid(&init_user_ns, cred->euid), 1181 from_kuid(&init_user_ns, cred->suid), 1182 from_kuid(&init_user_ns, cred->fsuid), 1183 from_kgid(&init_user_ns, cred->egid), 1184 from_kgid(&init_user_ns, cred->sgid), 1185 from_kgid(&init_user_ns, cred->fsgid), 1186 tsk->sessionid, tty); 1187 1188 get_task_comm(name, tsk); 1189 audit_log_format(ab, " comm="); 1190 audit_log_untrustedstring(ab, name); 1191 1192 if (mm) { 1193 down_read(&mm->mmap_sem); 1194 vma = mm->mmap; 1195 while (vma) { 1196 if ((vma->vm_flags & VM_EXECUTABLE) && 1197 vma->vm_file) { 1198 audit_log_d_path(ab, " exe=", 1199 &vma->vm_file->f_path); 1200 break; 1201 } 1202 vma = vma->vm_next; 1203 } 1204 up_read(&mm->mmap_sem); 1205 } 1206 audit_log_task_context(ab); 1207 } 1208 1209 EXPORT_SYMBOL(audit_log_task_info); 1210 1211 static int audit_log_pid_context(struct audit_context *context, pid_t pid, 1212 kuid_t auid, kuid_t uid, unsigned int sessionid, 1213 u32 sid, char *comm) 1214 { 1215 struct audit_buffer *ab; 1216 char *ctx = NULL; 1217 u32 len; 1218 int rc = 0; 1219 1220 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); 1221 if (!ab) 1222 return rc; 1223 1224 audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, 1225 from_kuid(&init_user_ns, auid), 1226 from_kuid(&init_user_ns, uid), sessionid); 1227 if (security_secid_to_secctx(sid, &ctx, &len)) { 1228 audit_log_format(ab, " obj=(none)"); 1229 rc = 1; 1230 } else { 1231 audit_log_format(ab, " obj=%s", ctx); 1232 security_release_secctx(ctx, len); 1233 } 1234 audit_log_format(ab, " ocomm="); 1235 audit_log_untrustedstring(ab, comm); 1236 audit_log_end(ab); 1237 1238 return rc; 1239 } 1240 1241 /* 1242 * to_send and len_sent accounting are very loose estimates. We aren't 1243 * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being 1244 * within about 500 bytes (next page boundary) 1245 * 1246 * why snprintf? an int is up to 12 digits long. if we just assumed when 1247 * logging that a[%d]= was going to be 16 characters long we would be wasting 1248 * space in every audit message. In one 7500 byte message we can log up to 1249 * about 1000 min size arguments. That comes down to about 50% waste of space 1250 * if we didn't do the snprintf to find out how long arg_num_len was. 1251 */ 1252 static int audit_log_single_execve_arg(struct audit_context *context, 1253 struct audit_buffer **ab, 1254 int arg_num, 1255 size_t *len_sent, 1256 const char __user *p, 1257 char *buf) 1258 { 1259 char arg_num_len_buf[12]; 1260 const char __user *tmp_p = p; 1261 /* how many digits are in arg_num? 5 is the length of ' a=""' */ 1262 size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 5; 1263 size_t len, len_left, to_send; 1264 size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN; 1265 unsigned int i, has_cntl = 0, too_long = 0; 1266 int ret; 1267 1268 /* strnlen_user includes the null we don't want to send */ 1269 len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1; 1270 1271 /* 1272 * We just created this mm, if we can't find the strings 1273 * we just copied into it something is _very_ wrong. Similar 1274 * for strings that are too long, we should not have created 1275 * any. 1276 */ 1277 if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) { 1278 WARN_ON(1); 1279 send_sig(SIGKILL, current, 0); 1280 return -1; 1281 } 1282 1283 /* walk the whole argument looking for non-ascii chars */ 1284 do { 1285 if (len_left > MAX_EXECVE_AUDIT_LEN) 1286 to_send = MAX_EXECVE_AUDIT_LEN; 1287 else 1288 to_send = len_left; 1289 ret = copy_from_user(buf, tmp_p, to_send); 1290 /* 1291 * There is no reason for this copy to be short. We just 1292 * copied them here, and the mm hasn't been exposed to user- 1293 * space yet. 1294 */ 1295 if (ret) { 1296 WARN_ON(1); 1297 send_sig(SIGKILL, current, 0); 1298 return -1; 1299 } 1300 buf[to_send] = '\0'; 1301 has_cntl = audit_string_contains_control(buf, to_send); 1302 if (has_cntl) { 1303 /* 1304 * hex messages get logged as 2 bytes, so we can only 1305 * send half as much in each message 1306 */ 1307 max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2; 1308 break; 1309 } 1310 len_left -= to_send; 1311 tmp_p += to_send; 1312 } while (len_left > 0); 1313 1314 len_left = len; 1315 1316 if (len > max_execve_audit_len) 1317 too_long = 1; 1318 1319 /* rewalk the argument actually logging the message */ 1320 for (i = 0; len_left > 0; i++) { 1321 int room_left; 1322 1323 if (len_left > max_execve_audit_len) 1324 to_send = max_execve_audit_len; 1325 else 1326 to_send = len_left; 1327 1328 /* do we have space left to send this argument in this ab? */ 1329 room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent; 1330 if (has_cntl) 1331 room_left -= (to_send * 2); 1332 else 1333 room_left -= to_send; 1334 if (room_left < 0) { 1335 *len_sent = 0; 1336 audit_log_end(*ab); 1337 *ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE); 1338 if (!*ab) 1339 return 0; 1340 } 1341 1342 /* 1343 * first record needs to say how long the original string was 1344 * so we can be sure nothing was lost. 1345 */ 1346 if ((i == 0) && (too_long)) 1347 audit_log_format(*ab, " a%d_len=%zu", arg_num, 1348 has_cntl ? 2*len : len); 1349 1350 /* 1351 * normally arguments are small enough to fit and we already 1352 * filled buf above when we checked for control characters 1353 * so don't bother with another copy_from_user 1354 */ 1355 if (len >= max_execve_audit_len) 1356 ret = copy_from_user(buf, p, to_send); 1357 else 1358 ret = 0; 1359 if (ret) { 1360 WARN_ON(1); 1361 send_sig(SIGKILL, current, 0); 1362 return -1; 1363 } 1364 buf[to_send] = '\0'; 1365 1366 /* actually log it */ 1367 audit_log_format(*ab, " a%d", arg_num); 1368 if (too_long) 1369 audit_log_format(*ab, "[%d]", i); 1370 audit_log_format(*ab, "="); 1371 if (has_cntl) 1372 audit_log_n_hex(*ab, buf, to_send); 1373 else 1374 audit_log_string(*ab, buf); 1375 1376 p += to_send; 1377 len_left -= to_send; 1378 *len_sent += arg_num_len; 1379 if (has_cntl) 1380 *len_sent += to_send * 2; 1381 else 1382 *len_sent += to_send; 1383 } 1384 /* include the null we didn't log */ 1385 return len + 1; 1386 } 1387 1388 static void audit_log_execve_info(struct audit_context *context, 1389 struct audit_buffer **ab, 1390 struct audit_aux_data_execve *axi) 1391 { 1392 int i, len; 1393 size_t len_sent = 0; 1394 const char __user *p; 1395 char *buf; 1396 1397 if (axi->mm != current->mm) 1398 return; /* execve failed, no additional info */ 1399 1400 p = (const char __user *)axi->mm->arg_start; 1401 1402 audit_log_format(*ab, "argc=%d", axi->argc); 1403 1404 /* 1405 * we need some kernel buffer to hold the userspace args. Just 1406 * allocate one big one rather than allocating one of the right size 1407 * for every single argument inside audit_log_single_execve_arg() 1408 * should be <8k allocation so should be pretty safe. 1409 */ 1410 buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL); 1411 if (!buf) { 1412 audit_panic("out of memory for argv string\n"); 1413 return; 1414 } 1415 1416 for (i = 0; i < axi->argc; i++) { 1417 len = audit_log_single_execve_arg(context, ab, i, 1418 &len_sent, p, buf); 1419 if (len <= 0) 1420 break; 1421 p += len; 1422 } 1423 kfree(buf); 1424 } 1425 1426 static void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap) 1427 { 1428 int i; 1429 1430 audit_log_format(ab, " %s=", prefix); 1431 CAP_FOR_EACH_U32(i) { 1432 audit_log_format(ab, "%08x", cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]); 1433 } 1434 } 1435 1436 static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) 1437 { 1438 kernel_cap_t *perm = &name->fcap.permitted; 1439 kernel_cap_t *inh = &name->fcap.inheritable; 1440 int log = 0; 1441 1442 if (!cap_isclear(*perm)) { 1443 audit_log_cap(ab, "cap_fp", perm); 1444 log = 1; 1445 } 1446 if (!cap_isclear(*inh)) { 1447 audit_log_cap(ab, "cap_fi", inh); 1448 log = 1; 1449 } 1450 1451 if (log) 1452 audit_log_format(ab, " cap_fe=%d cap_fver=%x", name->fcap.fE, name->fcap_ver); 1453 } 1454 1455 static void show_special(struct audit_context *context, int *call_panic) 1456 { 1457 struct audit_buffer *ab; 1458 int i; 1459 1460 ab = audit_log_start(context, GFP_KERNEL, context->type); 1461 if (!ab) 1462 return; 1463 1464 switch (context->type) { 1465 case AUDIT_SOCKETCALL: { 1466 int nargs = context->socketcall.nargs; 1467 audit_log_format(ab, "nargs=%d", nargs); 1468 for (i = 0; i < nargs; i++) 1469 audit_log_format(ab, " a%d=%lx", i, 1470 context->socketcall.args[i]); 1471 break; } 1472 case AUDIT_IPC: { 1473 u32 osid = context->ipc.osid; 1474 1475 audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho", 1476 from_kuid(&init_user_ns, context->ipc.uid), 1477 from_kgid(&init_user_ns, context->ipc.gid), 1478 context->ipc.mode); 1479 if (osid) { 1480 char *ctx = NULL; 1481 u32 len; 1482 if (security_secid_to_secctx(osid, &ctx, &len)) { 1483 audit_log_format(ab, " osid=%u", osid); 1484 *call_panic = 1; 1485 } else { 1486 audit_log_format(ab, " obj=%s", ctx); 1487 security_release_secctx(ctx, len); 1488 } 1489 } 1490 if (context->ipc.has_perm) { 1491 audit_log_end(ab); 1492 ab = audit_log_start(context, GFP_KERNEL, 1493 AUDIT_IPC_SET_PERM); 1494 audit_log_format(ab, 1495 "qbytes=%lx ouid=%u ogid=%u mode=%#ho", 1496 context->ipc.qbytes, 1497 context->ipc.perm_uid, 1498 context->ipc.perm_gid, 1499 context->ipc.perm_mode); 1500 if (!ab) 1501 return; 1502 } 1503 break; } 1504 case AUDIT_MQ_OPEN: { 1505 audit_log_format(ab, 1506 "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld " 1507 "mq_msgsize=%ld mq_curmsgs=%ld", 1508 context->mq_open.oflag, context->mq_open.mode, 1509 context->mq_open.attr.mq_flags, 1510 context->mq_open.attr.mq_maxmsg, 1511 context->mq_open.attr.mq_msgsize, 1512 context->mq_open.attr.mq_curmsgs); 1513 break; } 1514 case AUDIT_MQ_SENDRECV: { 1515 audit_log_format(ab, 1516 "mqdes=%d msg_len=%zd msg_prio=%u " 1517 "abs_timeout_sec=%ld abs_timeout_nsec=%ld", 1518 context->mq_sendrecv.mqdes, 1519 context->mq_sendrecv.msg_len, 1520 context->mq_sendrecv.msg_prio, 1521 context->mq_sendrecv.abs_timeout.tv_sec, 1522 context->mq_sendrecv.abs_timeout.tv_nsec); 1523 break; } 1524 case AUDIT_MQ_NOTIFY: { 1525 audit_log_format(ab, "mqdes=%d sigev_signo=%d", 1526 context->mq_notify.mqdes, 1527 context->mq_notify.sigev_signo); 1528 break; } 1529 case AUDIT_MQ_GETSETATTR: { 1530 struct mq_attr *attr = &context->mq_getsetattr.mqstat; 1531 audit_log_format(ab, 1532 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld " 1533 "mq_curmsgs=%ld ", 1534 context->mq_getsetattr.mqdes, 1535 attr->mq_flags, attr->mq_maxmsg, 1536 attr->mq_msgsize, attr->mq_curmsgs); 1537 break; } 1538 case AUDIT_CAPSET: { 1539 audit_log_format(ab, "pid=%d", context->capset.pid); 1540 audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable); 1541 audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted); 1542 audit_log_cap(ab, "cap_pe", &context->capset.cap.effective); 1543 break; } 1544 case AUDIT_MMAP: { 1545 audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd, 1546 context->mmap.flags); 1547 break; } 1548 } 1549 audit_log_end(ab); 1550 } 1551 1552 static void audit_log_name(struct audit_context *context, struct audit_names *n, 1553 int record_num, int *call_panic) 1554 { 1555 struct audit_buffer *ab; 1556 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH); 1557 if (!ab) 1558 return; /* audit_panic has been called */ 1559 1560 audit_log_format(ab, "item=%d", record_num); 1561 1562 if (n->name) { 1563 switch (n->name_len) { 1564 case AUDIT_NAME_FULL: 1565 /* log the full path */ 1566 audit_log_format(ab, " name="); 1567 audit_log_untrustedstring(ab, n->name); 1568 break; 1569 case 0: 1570 /* name was specified as a relative path and the 1571 * directory component is the cwd */ 1572 audit_log_d_path(ab, " name=", &context->pwd); 1573 break; 1574 default: 1575 /* log the name's directory component */ 1576 audit_log_format(ab, " name="); 1577 audit_log_n_untrustedstring(ab, n->name, 1578 n->name_len); 1579 } 1580 } else 1581 audit_log_format(ab, " name=(null)"); 1582 1583 if (n->ino != (unsigned long)-1) { 1584 audit_log_format(ab, " inode=%lu" 1585 " dev=%02x:%02x mode=%#ho" 1586 " ouid=%u ogid=%u rdev=%02x:%02x", 1587 n->ino, 1588 MAJOR(n->dev), 1589 MINOR(n->dev), 1590 n->mode, 1591 from_kuid(&init_user_ns, n->uid), 1592 from_kgid(&init_user_ns, n->gid), 1593 MAJOR(n->rdev), 1594 MINOR(n->rdev)); 1595 } 1596 if (n->osid != 0) { 1597 char *ctx = NULL; 1598 u32 len; 1599 if (security_secid_to_secctx( 1600 n->osid, &ctx, &len)) { 1601 audit_log_format(ab, " osid=%u", n->osid); 1602 *call_panic = 2; 1603 } else { 1604 audit_log_format(ab, " obj=%s", ctx); 1605 security_release_secctx(ctx, len); 1606 } 1607 } 1608 1609 audit_log_fcaps(ab, n); 1610 1611 audit_log_end(ab); 1612 } 1613 1614 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk) 1615 { 1616 int i, call_panic = 0; 1617 struct audit_buffer *ab; 1618 struct audit_aux_data *aux; 1619 struct audit_names *n; 1620 1621 /* tsk == current */ 1622 context->personality = tsk->personality; 1623 1624 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); 1625 if (!ab) 1626 return; /* audit_panic has been called */ 1627 audit_log_format(ab, "arch=%x syscall=%d", 1628 context->arch, context->major); 1629 if (context->personality != PER_LINUX) 1630 audit_log_format(ab, " per=%lx", context->personality); 1631 if (context->return_valid) 1632 audit_log_format(ab, " success=%s exit=%ld", 1633 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", 1634 context->return_code); 1635 1636 audit_log_format(ab, 1637 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d", 1638 context->argv[0], 1639 context->argv[1], 1640 context->argv[2], 1641 context->argv[3], 1642 context->name_count); 1643 1644 audit_log_task_info(ab, tsk); 1645 audit_log_key(ab, context->filterkey); 1646 audit_log_end(ab); 1647 1648 for (aux = context->aux; aux; aux = aux->next) { 1649 1650 ab = audit_log_start(context, GFP_KERNEL, aux->type); 1651 if (!ab) 1652 continue; /* audit_panic has been called */ 1653 1654 switch (aux->type) { 1655 1656 case AUDIT_EXECVE: { 1657 struct audit_aux_data_execve *axi = (void *)aux; 1658 audit_log_execve_info(context, &ab, axi); 1659 break; } 1660 1661 case AUDIT_BPRM_FCAPS: { 1662 struct audit_aux_data_bprm_fcaps *axs = (void *)aux; 1663 audit_log_format(ab, "fver=%x", axs->fcap_ver); 1664 audit_log_cap(ab, "fp", &axs->fcap.permitted); 1665 audit_log_cap(ab, "fi", &axs->fcap.inheritable); 1666 audit_log_format(ab, " fe=%d", axs->fcap.fE); 1667 audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted); 1668 audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable); 1669 audit_log_cap(ab, "old_pe", &axs->old_pcap.effective); 1670 audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted); 1671 audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable); 1672 audit_log_cap(ab, "new_pe", &axs->new_pcap.effective); 1673 break; } 1674 1675 } 1676 audit_log_end(ab); 1677 } 1678 1679 if (context->type) 1680 show_special(context, &call_panic); 1681 1682 if (context->fds[0] >= 0) { 1683 ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR); 1684 if (ab) { 1685 audit_log_format(ab, "fd0=%d fd1=%d", 1686 context->fds[0], context->fds[1]); 1687 audit_log_end(ab); 1688 } 1689 } 1690 1691 if (context->sockaddr_len) { 1692 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR); 1693 if (ab) { 1694 audit_log_format(ab, "saddr="); 1695 audit_log_n_hex(ab, (void *)context->sockaddr, 1696 context->sockaddr_len); 1697 audit_log_end(ab); 1698 } 1699 } 1700 1701 for (aux = context->aux_pids; aux; aux = aux->next) { 1702 struct audit_aux_data_pids *axs = (void *)aux; 1703 1704 for (i = 0; i < axs->pid_count; i++) 1705 if (audit_log_pid_context(context, axs->target_pid[i], 1706 axs->target_auid[i], 1707 axs->target_uid[i], 1708 axs->target_sessionid[i], 1709 axs->target_sid[i], 1710 axs->target_comm[i])) 1711 call_panic = 1; 1712 } 1713 1714 if (context->target_pid && 1715 audit_log_pid_context(context, context->target_pid, 1716 context->target_auid, context->target_uid, 1717 context->target_sessionid, 1718 context->target_sid, context->target_comm)) 1719 call_panic = 1; 1720 1721 if (context->pwd.dentry && context->pwd.mnt) { 1722 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); 1723 if (ab) { 1724 audit_log_d_path(ab, " cwd=", &context->pwd); 1725 audit_log_end(ab); 1726 } 1727 } 1728 1729 i = 0; 1730 list_for_each_entry(n, &context->names_list, list) 1731 audit_log_name(context, n, i++, &call_panic); 1732 1733 /* Send end of event record to help user space know we are finished */ 1734 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); 1735 if (ab) 1736 audit_log_end(ab); 1737 if (call_panic) 1738 audit_panic("error converting sid to string"); 1739 } 1740 1741 /** 1742 * audit_free - free a per-task audit context 1743 * @tsk: task whose audit context block to free 1744 * 1745 * Called from copy_process and do_exit 1746 */ 1747 void __audit_free(struct task_struct *tsk) 1748 { 1749 struct audit_context *context; 1750 1751 context = audit_get_context(tsk, 0, 0); 1752 if (!context) 1753 return; 1754 1755 /* Check for system calls that do not go through the exit 1756 * function (e.g., exit_group), then free context block. 1757 * We use GFP_ATOMIC here because we might be doing this 1758 * in the context of the idle thread */ 1759 /* that can happen only if we are called from do_exit() */ 1760 if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) 1761 audit_log_exit(context, tsk); 1762 if (!list_empty(&context->killed_trees)) 1763 audit_kill_trees(&context->killed_trees); 1764 1765 audit_free_context(context); 1766 } 1767 1768 /** 1769 * audit_syscall_entry - fill in an audit record at syscall entry 1770 * @arch: architecture type 1771 * @major: major syscall type (function) 1772 * @a1: additional syscall register 1 1773 * @a2: additional syscall register 2 1774 * @a3: additional syscall register 3 1775 * @a4: additional syscall register 4 1776 * 1777 * Fill in audit context at syscall entry. This only happens if the 1778 * audit context was created when the task was created and the state or 1779 * filters demand the audit context be built. If the state from the 1780 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, 1781 * then the record will be written at syscall exit time (otherwise, it 1782 * will only be written if another part of the kernel requests that it 1783 * be written). 1784 */ 1785 void __audit_syscall_entry(int arch, int major, 1786 unsigned long a1, unsigned long a2, 1787 unsigned long a3, unsigned long a4) 1788 { 1789 struct task_struct *tsk = current; 1790 struct audit_context *context = tsk->audit_context; 1791 enum audit_state state; 1792 1793 if (!context) 1794 return; 1795 1796 /* 1797 * This happens only on certain architectures that make system 1798 * calls in kernel_thread via the entry.S interface, instead of 1799 * with direct calls. (If you are porting to a new 1800 * architecture, hitting this condition can indicate that you 1801 * got the _exit/_leave calls backward in entry.S.) 1802 * 1803 * i386 no 1804 * x86_64 no 1805 * ppc64 yes (see arch/powerpc/platforms/iseries/misc.S) 1806 * 1807 * This also happens with vm86 emulation in a non-nested manner 1808 * (entries without exits), so this case must be caught. 1809 */ 1810 if (context->in_syscall) { 1811 struct audit_context *newctx; 1812 1813 #if AUDIT_DEBUG 1814 printk(KERN_ERR 1815 "audit(:%d) pid=%d in syscall=%d;" 1816 " entering syscall=%d\n", 1817 context->serial, tsk->pid, context->major, major); 1818 #endif 1819 newctx = audit_alloc_context(context->state); 1820 if (newctx) { 1821 newctx->previous = context; 1822 context = newctx; 1823 tsk->audit_context = newctx; 1824 } else { 1825 /* If we can't alloc a new context, the best we 1826 * can do is to leak memory (any pending putname 1827 * will be lost). The only other alternative is 1828 * to abandon auditing. */ 1829 audit_zero_context(context, context->state); 1830 } 1831 } 1832 BUG_ON(context->in_syscall || context->name_count); 1833 1834 if (!audit_enabled) 1835 return; 1836 1837 context->arch = arch; 1838 context->major = major; 1839 context->argv[0] = a1; 1840 context->argv[1] = a2; 1841 context->argv[2] = a3; 1842 context->argv[3] = a4; 1843 1844 state = context->state; 1845 context->dummy = !audit_n_rules; 1846 if (!context->dummy && state == AUDIT_BUILD_CONTEXT) { 1847 context->prio = 0; 1848 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]); 1849 } 1850 if (state == AUDIT_DISABLED) 1851 return; 1852 1853 context->serial = 0; 1854 context->ctime = CURRENT_TIME; 1855 context->in_syscall = 1; 1856 context->current_state = state; 1857 context->ppid = 0; 1858 } 1859 1860 /** 1861 * audit_syscall_exit - deallocate audit context after a system call 1862 * @success: success value of the syscall 1863 * @return_code: return value of the syscall 1864 * 1865 * Tear down after system call. If the audit context has been marked as 1866 * auditable (either because of the AUDIT_RECORD_CONTEXT state from 1867 * filtering, or because some other part of the kernel wrote an audit 1868 * message), then write out the syscall information. In call cases, 1869 * free the names stored from getname(). 1870 */ 1871 void __audit_syscall_exit(int success, long return_code) 1872 { 1873 struct task_struct *tsk = current; 1874 struct audit_context *context; 1875 1876 if (success) 1877 success = AUDITSC_SUCCESS; 1878 else 1879 success = AUDITSC_FAILURE; 1880 1881 context = audit_get_context(tsk, success, return_code); 1882 if (!context) 1883 return; 1884 1885 if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) 1886 audit_log_exit(context, tsk); 1887 1888 context->in_syscall = 0; 1889 context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 1890 1891 if (!list_empty(&context->killed_trees)) 1892 audit_kill_trees(&context->killed_trees); 1893 1894 if (context->previous) { 1895 struct audit_context *new_context = context->previous; 1896 context->previous = NULL; 1897 audit_free_context(context); 1898 tsk->audit_context = new_context; 1899 } else { 1900 audit_free_names(context); 1901 unroll_tree_refs(context, NULL, 0); 1902 audit_free_aux(context); 1903 context->aux = NULL; 1904 context->aux_pids = NULL; 1905 context->target_pid = 0; 1906 context->target_sid = 0; 1907 context->sockaddr_len = 0; 1908 context->type = 0; 1909 context->fds[0] = -1; 1910 if (context->state != AUDIT_RECORD_CONTEXT) { 1911 kfree(context->filterkey); 1912 context->filterkey = NULL; 1913 } 1914 tsk->audit_context = context; 1915 } 1916 } 1917 1918 static inline void handle_one(const struct inode *inode) 1919 { 1920 #ifdef CONFIG_AUDIT_TREE 1921 struct audit_context *context; 1922 struct audit_tree_refs *p; 1923 struct audit_chunk *chunk; 1924 int count; 1925 if (likely(hlist_empty(&inode->i_fsnotify_marks))) 1926 return; 1927 context = current->audit_context; 1928 p = context->trees; 1929 count = context->tree_count; 1930 rcu_read_lock(); 1931 chunk = audit_tree_lookup(inode); 1932 rcu_read_unlock(); 1933 if (!chunk) 1934 return; 1935 if (likely(put_tree_ref(context, chunk))) 1936 return; 1937 if (unlikely(!grow_tree_refs(context))) { 1938 printk(KERN_WARNING "out of memory, audit has lost a tree reference\n"); 1939 audit_set_auditable(context); 1940 audit_put_chunk(chunk); 1941 unroll_tree_refs(context, p, count); 1942 return; 1943 } 1944 put_tree_ref(context, chunk); 1945 #endif 1946 } 1947 1948 static void handle_path(const struct dentry *dentry) 1949 { 1950 #ifdef CONFIG_AUDIT_TREE 1951 struct audit_context *context; 1952 struct audit_tree_refs *p; 1953 const struct dentry *d, *parent; 1954 struct audit_chunk *drop; 1955 unsigned long seq; 1956 int count; 1957 1958 context = current->audit_context; 1959 p = context->trees; 1960 count = context->tree_count; 1961 retry: 1962 drop = NULL; 1963 d = dentry; 1964 rcu_read_lock(); 1965 seq = read_seqbegin(&rename_lock); 1966 for(;;) { 1967 struct inode *inode = d->d_inode; 1968 if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) { 1969 struct audit_chunk *chunk; 1970 chunk = audit_tree_lookup(inode); 1971 if (chunk) { 1972 if (unlikely(!put_tree_ref(context, chunk))) { 1973 drop = chunk; 1974 break; 1975 } 1976 } 1977 } 1978 parent = d->d_parent; 1979 if (parent == d) 1980 break; 1981 d = parent; 1982 } 1983 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */ 1984 rcu_read_unlock(); 1985 if (!drop) { 1986 /* just a race with rename */ 1987 unroll_tree_refs(context, p, count); 1988 goto retry; 1989 } 1990 audit_put_chunk(drop); 1991 if (grow_tree_refs(context)) { 1992 /* OK, got more space */ 1993 unroll_tree_refs(context, p, count); 1994 goto retry; 1995 } 1996 /* too bad */ 1997 printk(KERN_WARNING 1998 "out of memory, audit has lost a tree reference\n"); 1999 unroll_tree_refs(context, p, count); 2000 audit_set_auditable(context); 2001 return; 2002 } 2003 rcu_read_unlock(); 2004 #endif 2005 } 2006 2007 static struct audit_names *audit_alloc_name(struct audit_context *context) 2008 { 2009 struct audit_names *aname; 2010 2011 if (context->name_count < AUDIT_NAMES) { 2012 aname = &context->preallocated_names[context->name_count]; 2013 memset(aname, 0, sizeof(*aname)); 2014 } else { 2015 aname = kzalloc(sizeof(*aname), GFP_NOFS); 2016 if (!aname) 2017 return NULL; 2018 aname->should_free = true; 2019 } 2020 2021 aname->ino = (unsigned long)-1; 2022 list_add_tail(&aname->list, &context->names_list); 2023 2024 context->name_count++; 2025 #if AUDIT_DEBUG 2026 context->ino_count++; 2027 #endif 2028 return aname; 2029 } 2030 2031 /** 2032 * audit_getname - add a name to the list 2033 * @name: name to add 2034 * 2035 * Add a name to the list of audit names for this context. 2036 * Called from fs/namei.c:getname(). 2037 */ 2038 void __audit_getname(const char *name) 2039 { 2040 struct audit_context *context = current->audit_context; 2041 struct audit_names *n; 2042 2043 if (!context->in_syscall) { 2044 #if AUDIT_DEBUG == 2 2045 printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n", 2046 __FILE__, __LINE__, context->serial, name); 2047 dump_stack(); 2048 #endif 2049 return; 2050 } 2051 2052 n = audit_alloc_name(context); 2053 if (!n) 2054 return; 2055 2056 n->name = name; 2057 n->name_len = AUDIT_NAME_FULL; 2058 n->name_put = true; 2059 2060 if (!context->pwd.dentry) 2061 get_fs_pwd(current->fs, &context->pwd); 2062 } 2063 2064 /* audit_putname - intercept a putname request 2065 * @name: name to intercept and delay for putname 2066 * 2067 * If we have stored the name from getname in the audit context, 2068 * then we delay the putname until syscall exit. 2069 * Called from include/linux/fs.h:putname(). 2070 */ 2071 void audit_putname(const char *name) 2072 { 2073 struct audit_context *context = current->audit_context; 2074 2075 BUG_ON(!context); 2076 if (!context->in_syscall) { 2077 #if AUDIT_DEBUG == 2 2078 printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n", 2079 __FILE__, __LINE__, context->serial, name); 2080 if (context->name_count) { 2081 struct audit_names *n; 2082 int i; 2083 2084 list_for_each_entry(n, &context->names_list, list) 2085 printk(KERN_ERR "name[%d] = %p = %s\n", i, 2086 n->name, n->name ?: "(null)"); 2087 } 2088 #endif 2089 __putname(name); 2090 } 2091 #if AUDIT_DEBUG 2092 else { 2093 ++context->put_count; 2094 if (context->put_count > context->name_count) { 2095 printk(KERN_ERR "%s:%d(:%d): major=%d" 2096 " in_syscall=%d putname(%p) name_count=%d" 2097 " put_count=%d\n", 2098 __FILE__, __LINE__, 2099 context->serial, context->major, 2100 context->in_syscall, name, context->name_count, 2101 context->put_count); 2102 dump_stack(); 2103 } 2104 } 2105 #endif 2106 } 2107 2108 static inline int audit_copy_fcaps(struct audit_names *name, const struct dentry *dentry) 2109 { 2110 struct cpu_vfs_cap_data caps; 2111 int rc; 2112 2113 if (!dentry) 2114 return 0; 2115 2116 rc = get_vfs_caps_from_disk(dentry, &caps); 2117 if (rc) 2118 return rc; 2119 2120 name->fcap.permitted = caps.permitted; 2121 name->fcap.inheritable = caps.inheritable; 2122 name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 2123 name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; 2124 2125 return 0; 2126 } 2127 2128 2129 /* Copy inode data into an audit_names. */ 2130 static void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, 2131 const struct inode *inode) 2132 { 2133 name->ino = inode->i_ino; 2134 name->dev = inode->i_sb->s_dev; 2135 name->mode = inode->i_mode; 2136 name->uid = inode->i_uid; 2137 name->gid = inode->i_gid; 2138 name->rdev = inode->i_rdev; 2139 security_inode_getsecid(inode, &name->osid); 2140 audit_copy_fcaps(name, dentry); 2141 } 2142 2143 /** 2144 * audit_inode - store the inode and device from a lookup 2145 * @name: name being audited 2146 * @dentry: dentry being audited 2147 * 2148 * Called from fs/namei.c:path_lookup(). 2149 */ 2150 void __audit_inode(const char *name, const struct dentry *dentry) 2151 { 2152 struct audit_context *context = current->audit_context; 2153 const struct inode *inode = dentry->d_inode; 2154 struct audit_names *n; 2155 2156 if (!context->in_syscall) 2157 return; 2158 2159 list_for_each_entry_reverse(n, &context->names_list, list) { 2160 if (n->name && (n->name == name)) 2161 goto out; 2162 } 2163 2164 /* unable to find the name from a previous getname() */ 2165 n = audit_alloc_name(context); 2166 if (!n) 2167 return; 2168 out: 2169 handle_path(dentry); 2170 audit_copy_inode(n, dentry, inode); 2171 } 2172 2173 /** 2174 * audit_inode_child - collect inode info for created/removed objects 2175 * @dentry: dentry being audited 2176 * @parent: inode of dentry parent 2177 * 2178 * For syscalls that create or remove filesystem objects, audit_inode 2179 * can only collect information for the filesystem object's parent. 2180 * This call updates the audit context with the child's information. 2181 * Syscalls that create a new filesystem object must be hooked after 2182 * the object is created. Syscalls that remove a filesystem object 2183 * must be hooked prior, in order to capture the target inode during 2184 * unsuccessful attempts. 2185 */ 2186 void __audit_inode_child(const struct dentry *dentry, 2187 const struct inode *parent) 2188 { 2189 struct audit_context *context = current->audit_context; 2190 const char *found_parent = NULL, *found_child = NULL; 2191 const struct inode *inode = dentry->d_inode; 2192 const char *dname = dentry->d_name.name; 2193 struct audit_names *n; 2194 int dirlen = 0; 2195 2196 if (!context->in_syscall) 2197 return; 2198 2199 if (inode) 2200 handle_one(inode); 2201 2202 /* parent is more likely, look for it first */ 2203 list_for_each_entry(n, &context->names_list, list) { 2204 if (!n->name) 2205 continue; 2206 2207 if (n->ino == parent->i_ino && 2208 !audit_compare_dname_path(dname, n->name, &dirlen)) { 2209 n->name_len = dirlen; /* update parent data in place */ 2210 found_parent = n->name; 2211 goto add_names; 2212 } 2213 } 2214 2215 /* no matching parent, look for matching child */ 2216 list_for_each_entry(n, &context->names_list, list) { 2217 if (!n->name) 2218 continue; 2219 2220 /* strcmp() is the more likely scenario */ 2221 if (!strcmp(dname, n->name) || 2222 !audit_compare_dname_path(dname, n->name, &dirlen)) { 2223 if (inode) 2224 audit_copy_inode(n, NULL, inode); 2225 else 2226 n->ino = (unsigned long)-1; 2227 found_child = n->name; 2228 goto add_names; 2229 } 2230 } 2231 2232 add_names: 2233 if (!found_parent) { 2234 n = audit_alloc_name(context); 2235 if (!n) 2236 return; 2237 audit_copy_inode(n, NULL, parent); 2238 } 2239 2240 if (!found_child) { 2241 n = audit_alloc_name(context); 2242 if (!n) 2243 return; 2244 2245 /* Re-use the name belonging to the slot for a matching parent 2246 * directory. All names for this context are relinquished in 2247 * audit_free_names() */ 2248 if (found_parent) { 2249 n->name = found_parent; 2250 n->name_len = AUDIT_NAME_FULL; 2251 /* don't call __putname() */ 2252 n->name_put = false; 2253 } 2254 2255 if (inode) 2256 audit_copy_inode(n, NULL, inode); 2257 } 2258 } 2259 EXPORT_SYMBOL_GPL(__audit_inode_child); 2260 2261 /** 2262 * auditsc_get_stamp - get local copies of audit_context values 2263 * @ctx: audit_context for the task 2264 * @t: timespec to store time recorded in the audit_context 2265 * @serial: serial value that is recorded in the audit_context 2266 * 2267 * Also sets the context as auditable. 2268 */ 2269 int auditsc_get_stamp(struct audit_context *ctx, 2270 struct timespec *t, unsigned int *serial) 2271 { 2272 if (!ctx->in_syscall) 2273 return 0; 2274 if (!ctx->serial) 2275 ctx->serial = audit_serial(); 2276 t->tv_sec = ctx->ctime.tv_sec; 2277 t->tv_nsec = ctx->ctime.tv_nsec; 2278 *serial = ctx->serial; 2279 if (!ctx->prio) { 2280 ctx->prio = 1; 2281 ctx->current_state = AUDIT_RECORD_CONTEXT; 2282 } 2283 return 1; 2284 } 2285 2286 /* global counter which is incremented every time something logs in */ 2287 static atomic_t session_id = ATOMIC_INIT(0); 2288 2289 /** 2290 * audit_set_loginuid - set current task's audit_context loginuid 2291 * @loginuid: loginuid value 2292 * 2293 * Returns 0. 2294 * 2295 * Called (set) from fs/proc/base.c::proc_loginuid_write(). 2296 */ 2297 int audit_set_loginuid(kuid_t loginuid) 2298 { 2299 struct task_struct *task = current; 2300 struct audit_context *context = task->audit_context; 2301 unsigned int sessionid; 2302 2303 #ifdef CONFIG_AUDIT_LOGINUID_IMMUTABLE 2304 if (uid_valid(task->loginuid)) 2305 return -EPERM; 2306 #else /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */ 2307 if (!capable(CAP_AUDIT_CONTROL)) 2308 return -EPERM; 2309 #endif /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */ 2310 2311 sessionid = atomic_inc_return(&session_id); 2312 if (context && context->in_syscall) { 2313 struct audit_buffer *ab; 2314 2315 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); 2316 if (ab) { 2317 audit_log_format(ab, "login pid=%d uid=%u " 2318 "old auid=%u new auid=%u" 2319 " old ses=%u new ses=%u", 2320 task->pid, 2321 from_kuid(&init_user_ns, task_uid(task)), 2322 from_kuid(&init_user_ns, task->loginuid), 2323 from_kuid(&init_user_ns, loginuid), 2324 task->sessionid, sessionid); 2325 audit_log_end(ab); 2326 } 2327 } 2328 task->sessionid = sessionid; 2329 task->loginuid = loginuid; 2330 return 0; 2331 } 2332 2333 /** 2334 * __audit_mq_open - record audit data for a POSIX MQ open 2335 * @oflag: open flag 2336 * @mode: mode bits 2337 * @attr: queue attributes 2338 * 2339 */ 2340 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr) 2341 { 2342 struct audit_context *context = current->audit_context; 2343 2344 if (attr) 2345 memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr)); 2346 else 2347 memset(&context->mq_open.attr, 0, sizeof(struct mq_attr)); 2348 2349 context->mq_open.oflag = oflag; 2350 context->mq_open.mode = mode; 2351 2352 context->type = AUDIT_MQ_OPEN; 2353 } 2354 2355 /** 2356 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive 2357 * @mqdes: MQ descriptor 2358 * @msg_len: Message length 2359 * @msg_prio: Message priority 2360 * @abs_timeout: Message timeout in absolute time 2361 * 2362 */ 2363 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, 2364 const struct timespec *abs_timeout) 2365 { 2366 struct audit_context *context = current->audit_context; 2367 struct timespec *p = &context->mq_sendrecv.abs_timeout; 2368 2369 if (abs_timeout) 2370 memcpy(p, abs_timeout, sizeof(struct timespec)); 2371 else 2372 memset(p, 0, sizeof(struct timespec)); 2373 2374 context->mq_sendrecv.mqdes = mqdes; 2375 context->mq_sendrecv.msg_len = msg_len; 2376 context->mq_sendrecv.msg_prio = msg_prio; 2377 2378 context->type = AUDIT_MQ_SENDRECV; 2379 } 2380 2381 /** 2382 * __audit_mq_notify - record audit data for a POSIX MQ notify 2383 * @mqdes: MQ descriptor 2384 * @notification: Notification event 2385 * 2386 */ 2387 2388 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification) 2389 { 2390 struct audit_context *context = current->audit_context; 2391 2392 if (notification) 2393 context->mq_notify.sigev_signo = notification->sigev_signo; 2394 else 2395 context->mq_notify.sigev_signo = 0; 2396 2397 context->mq_notify.mqdes = mqdes; 2398 context->type = AUDIT_MQ_NOTIFY; 2399 } 2400 2401 /** 2402 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute 2403 * @mqdes: MQ descriptor 2404 * @mqstat: MQ flags 2405 * 2406 */ 2407 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) 2408 { 2409 struct audit_context *context = current->audit_context; 2410 context->mq_getsetattr.mqdes = mqdes; 2411 context->mq_getsetattr.mqstat = *mqstat; 2412 context->type = AUDIT_MQ_GETSETATTR; 2413 } 2414 2415 /** 2416 * audit_ipc_obj - record audit data for ipc object 2417 * @ipcp: ipc permissions 2418 * 2419 */ 2420 void __audit_ipc_obj(struct kern_ipc_perm *ipcp) 2421 { 2422 struct audit_context *context = current->audit_context; 2423 context->ipc.uid = ipcp->uid; 2424 context->ipc.gid = ipcp->gid; 2425 context->ipc.mode = ipcp->mode; 2426 context->ipc.has_perm = 0; 2427 security_ipc_getsecid(ipcp, &context->ipc.osid); 2428 context->type = AUDIT_IPC; 2429 } 2430 2431 /** 2432 * audit_ipc_set_perm - record audit data for new ipc permissions 2433 * @qbytes: msgq bytes 2434 * @uid: msgq user id 2435 * @gid: msgq group id 2436 * @mode: msgq mode (permissions) 2437 * 2438 * Called only after audit_ipc_obj(). 2439 */ 2440 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode) 2441 { 2442 struct audit_context *context = current->audit_context; 2443 2444 context->ipc.qbytes = qbytes; 2445 context->ipc.perm_uid = uid; 2446 context->ipc.perm_gid = gid; 2447 context->ipc.perm_mode = mode; 2448 context->ipc.has_perm = 1; 2449 } 2450 2451 int __audit_bprm(struct linux_binprm *bprm) 2452 { 2453 struct audit_aux_data_execve *ax; 2454 struct audit_context *context = current->audit_context; 2455 2456 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2457 if (!ax) 2458 return -ENOMEM; 2459 2460 ax->argc = bprm->argc; 2461 ax->envc = bprm->envc; 2462 ax->mm = bprm->mm; 2463 ax->d.type = AUDIT_EXECVE; 2464 ax->d.next = context->aux; 2465 context->aux = (void *)ax; 2466 return 0; 2467 } 2468 2469 2470 /** 2471 * audit_socketcall - record audit data for sys_socketcall 2472 * @nargs: number of args 2473 * @args: args array 2474 * 2475 */ 2476 void __audit_socketcall(int nargs, unsigned long *args) 2477 { 2478 struct audit_context *context = current->audit_context; 2479 2480 context->type = AUDIT_SOCKETCALL; 2481 context->socketcall.nargs = nargs; 2482 memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long)); 2483 } 2484 2485 /** 2486 * __audit_fd_pair - record audit data for pipe and socketpair 2487 * @fd1: the first file descriptor 2488 * @fd2: the second file descriptor 2489 * 2490 */ 2491 void __audit_fd_pair(int fd1, int fd2) 2492 { 2493 struct audit_context *context = current->audit_context; 2494 context->fds[0] = fd1; 2495 context->fds[1] = fd2; 2496 } 2497 2498 /** 2499 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto 2500 * @len: data length in user space 2501 * @a: data address in kernel space 2502 * 2503 * Returns 0 for success or NULL context or < 0 on error. 2504 */ 2505 int __audit_sockaddr(int len, void *a) 2506 { 2507 struct audit_context *context = current->audit_context; 2508 2509 if (!context->sockaddr) { 2510 void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL); 2511 if (!p) 2512 return -ENOMEM; 2513 context->sockaddr = p; 2514 } 2515 2516 context->sockaddr_len = len; 2517 memcpy(context->sockaddr, a, len); 2518 return 0; 2519 } 2520 2521 void __audit_ptrace(struct task_struct *t) 2522 { 2523 struct audit_context *context = current->audit_context; 2524 2525 context->target_pid = t->pid; 2526 context->target_auid = audit_get_loginuid(t); 2527 context->target_uid = task_uid(t); 2528 context->target_sessionid = audit_get_sessionid(t); 2529 security_task_getsecid(t, &context->target_sid); 2530 memcpy(context->target_comm, t->comm, TASK_COMM_LEN); 2531 } 2532 2533 /** 2534 * audit_signal_info - record signal info for shutting down audit subsystem 2535 * @sig: signal value 2536 * @t: task being signaled 2537 * 2538 * If the audit subsystem is being terminated, record the task (pid) 2539 * and uid that is doing that. 2540 */ 2541 int __audit_signal_info(int sig, struct task_struct *t) 2542 { 2543 struct audit_aux_data_pids *axp; 2544 struct task_struct *tsk = current; 2545 struct audit_context *ctx = tsk->audit_context; 2546 kuid_t uid = current_uid(), t_uid = task_uid(t); 2547 2548 if (audit_pid && t->tgid == audit_pid) { 2549 if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) { 2550 audit_sig_pid = tsk->pid; 2551 if (uid_valid(tsk->loginuid)) 2552 audit_sig_uid = tsk->loginuid; 2553 else 2554 audit_sig_uid = uid; 2555 security_task_getsecid(tsk, &audit_sig_sid); 2556 } 2557 if (!audit_signals || audit_dummy_context()) 2558 return 0; 2559 } 2560 2561 /* optimize the common case by putting first signal recipient directly 2562 * in audit_context */ 2563 if (!ctx->target_pid) { 2564 ctx->target_pid = t->tgid; 2565 ctx->target_auid = audit_get_loginuid(t); 2566 ctx->target_uid = t_uid; 2567 ctx->target_sessionid = audit_get_sessionid(t); 2568 security_task_getsecid(t, &ctx->target_sid); 2569 memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); 2570 return 0; 2571 } 2572 2573 axp = (void *)ctx->aux_pids; 2574 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { 2575 axp = kzalloc(sizeof(*axp), GFP_ATOMIC); 2576 if (!axp) 2577 return -ENOMEM; 2578 2579 axp->d.type = AUDIT_OBJ_PID; 2580 axp->d.next = ctx->aux_pids; 2581 ctx->aux_pids = (void *)axp; 2582 } 2583 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); 2584 2585 axp->target_pid[axp->pid_count] = t->tgid; 2586 axp->target_auid[axp->pid_count] = audit_get_loginuid(t); 2587 axp->target_uid[axp->pid_count] = t_uid; 2588 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); 2589 security_task_getsecid(t, &axp->target_sid[axp->pid_count]); 2590 memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); 2591 axp->pid_count++; 2592 2593 return 0; 2594 } 2595 2596 /** 2597 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps 2598 * @bprm: pointer to the bprm being processed 2599 * @new: the proposed new credentials 2600 * @old: the old credentials 2601 * 2602 * Simply check if the proc already has the caps given by the file and if not 2603 * store the priv escalation info for later auditing at the end of the syscall 2604 * 2605 * -Eric 2606 */ 2607 int __audit_log_bprm_fcaps(struct linux_binprm *bprm, 2608 const struct cred *new, const struct cred *old) 2609 { 2610 struct audit_aux_data_bprm_fcaps *ax; 2611 struct audit_context *context = current->audit_context; 2612 struct cpu_vfs_cap_data vcaps; 2613 struct dentry *dentry; 2614 2615 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2616 if (!ax) 2617 return -ENOMEM; 2618 2619 ax->d.type = AUDIT_BPRM_FCAPS; 2620 ax->d.next = context->aux; 2621 context->aux = (void *)ax; 2622 2623 dentry = dget(bprm->file->f_dentry); 2624 get_vfs_caps_from_disk(dentry, &vcaps); 2625 dput(dentry); 2626 2627 ax->fcap.permitted = vcaps.permitted; 2628 ax->fcap.inheritable = vcaps.inheritable; 2629 ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 2630 ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; 2631 2632 ax->old_pcap.permitted = old->cap_permitted; 2633 ax->old_pcap.inheritable = old->cap_inheritable; 2634 ax->old_pcap.effective = old->cap_effective; 2635 2636 ax->new_pcap.permitted = new->cap_permitted; 2637 ax->new_pcap.inheritable = new->cap_inheritable; 2638 ax->new_pcap.effective = new->cap_effective; 2639 return 0; 2640 } 2641 2642 /** 2643 * __audit_log_capset - store information about the arguments to the capset syscall 2644 * @pid: target pid of the capset call 2645 * @new: the new credentials 2646 * @old: the old (current) credentials 2647 * 2648 * Record the aguments userspace sent to sys_capset for later printing by the 2649 * audit system if applicable 2650 */ 2651 void __audit_log_capset(pid_t pid, 2652 const struct cred *new, const struct cred *old) 2653 { 2654 struct audit_context *context = current->audit_context; 2655 context->capset.pid = pid; 2656 context->capset.cap.effective = new->cap_effective; 2657 context->capset.cap.inheritable = new->cap_effective; 2658 context->capset.cap.permitted = new->cap_permitted; 2659 context->type = AUDIT_CAPSET; 2660 } 2661 2662 void __audit_mmap_fd(int fd, int flags) 2663 { 2664 struct audit_context *context = current->audit_context; 2665 context->mmap.fd = fd; 2666 context->mmap.flags = flags; 2667 context->type = AUDIT_MMAP; 2668 } 2669 2670 static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr) 2671 { 2672 kuid_t auid, uid; 2673 kgid_t gid; 2674 unsigned int sessionid; 2675 2676 auid = audit_get_loginuid(current); 2677 sessionid = audit_get_sessionid(current); 2678 current_uid_gid(&uid, &gid); 2679 2680 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", 2681 from_kuid(&init_user_ns, auid), 2682 from_kuid(&init_user_ns, uid), 2683 from_kgid(&init_user_ns, gid), 2684 sessionid); 2685 audit_log_task_context(ab); 2686 audit_log_format(ab, " pid=%d comm=", current->pid); 2687 audit_log_untrustedstring(ab, current->comm); 2688 audit_log_format(ab, " reason="); 2689 audit_log_string(ab, reason); 2690 audit_log_format(ab, " sig=%ld", signr); 2691 } 2692 /** 2693 * audit_core_dumps - record information about processes that end abnormally 2694 * @signr: signal value 2695 * 2696 * If a process ends with a core dump, something fishy is going on and we 2697 * should record the event for investigation. 2698 */ 2699 void audit_core_dumps(long signr) 2700 { 2701 struct audit_buffer *ab; 2702 2703 if (!audit_enabled) 2704 return; 2705 2706 if (signr == SIGQUIT) /* don't care for those */ 2707 return; 2708 2709 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); 2710 audit_log_abend(ab, "memory violation", signr); 2711 audit_log_end(ab); 2712 } 2713 2714 void __audit_seccomp(unsigned long syscall, long signr, int code) 2715 { 2716 struct audit_buffer *ab; 2717 2718 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); 2719 audit_log_abend(ab, "seccomp", signr); 2720 audit_log_format(ab, " syscall=%ld", syscall); 2721 audit_log_format(ab, " compat=%d", is_compat_task()); 2722 audit_log_format(ab, " ip=0x%lx", KSTK_EIP(current)); 2723 audit_log_format(ab, " code=0x%x", code); 2724 audit_log_end(ab); 2725 } 2726 2727 struct list_head *audit_killed_trees(void) 2728 { 2729 struct audit_context *ctx = current->audit_context; 2730 if (likely(!ctx || !ctx->in_syscall)) 2731 return NULL; 2732 return &ctx->killed_trees; 2733 } 2734