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 char *tty; 1155 1156 if (!ab) 1157 return; 1158 1159 /* tsk == current */ 1160 cred = current_cred(); 1161 1162 spin_lock_irq(&tsk->sighand->siglock); 1163 if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name) 1164 tty = tsk->signal->tty->name; 1165 else 1166 tty = "(none)"; 1167 spin_unlock_irq(&tsk->sighand->siglock); 1168 1169 1170 audit_log_format(ab, 1171 " ppid=%ld pid=%d auid=%u uid=%u gid=%u" 1172 " euid=%u suid=%u fsuid=%u" 1173 " egid=%u sgid=%u fsgid=%u ses=%u tty=%s", 1174 sys_getppid(), 1175 tsk->pid, 1176 from_kuid(&init_user_ns, tsk->loginuid), 1177 from_kuid(&init_user_ns, cred->uid), 1178 from_kgid(&init_user_ns, cred->gid), 1179 from_kuid(&init_user_ns, cred->euid), 1180 from_kuid(&init_user_ns, cred->suid), 1181 from_kuid(&init_user_ns, cred->fsuid), 1182 from_kgid(&init_user_ns, cred->egid), 1183 from_kgid(&init_user_ns, cred->sgid), 1184 from_kgid(&init_user_ns, cred->fsgid), 1185 tsk->sessionid, tty); 1186 1187 get_task_comm(name, tsk); 1188 audit_log_format(ab, " comm="); 1189 audit_log_untrustedstring(ab, name); 1190 1191 if (mm) { 1192 down_read(&mm->mmap_sem); 1193 if (mm->exe_file) 1194 audit_log_d_path(ab, " exe=", &mm->exe_file->f_path); 1195 up_read(&mm->mmap_sem); 1196 } 1197 audit_log_task_context(ab); 1198 } 1199 1200 EXPORT_SYMBOL(audit_log_task_info); 1201 1202 static int audit_log_pid_context(struct audit_context *context, pid_t pid, 1203 kuid_t auid, kuid_t uid, unsigned int sessionid, 1204 u32 sid, char *comm) 1205 { 1206 struct audit_buffer *ab; 1207 char *ctx = NULL; 1208 u32 len; 1209 int rc = 0; 1210 1211 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); 1212 if (!ab) 1213 return rc; 1214 1215 audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, 1216 from_kuid(&init_user_ns, auid), 1217 from_kuid(&init_user_ns, uid), sessionid); 1218 if (security_secid_to_secctx(sid, &ctx, &len)) { 1219 audit_log_format(ab, " obj=(none)"); 1220 rc = 1; 1221 } else { 1222 audit_log_format(ab, " obj=%s", ctx); 1223 security_release_secctx(ctx, len); 1224 } 1225 audit_log_format(ab, " ocomm="); 1226 audit_log_untrustedstring(ab, comm); 1227 audit_log_end(ab); 1228 1229 return rc; 1230 } 1231 1232 /* 1233 * to_send and len_sent accounting are very loose estimates. We aren't 1234 * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being 1235 * within about 500 bytes (next page boundary) 1236 * 1237 * why snprintf? an int is up to 12 digits long. if we just assumed when 1238 * logging that a[%d]= was going to be 16 characters long we would be wasting 1239 * space in every audit message. In one 7500 byte message we can log up to 1240 * about 1000 min size arguments. That comes down to about 50% waste of space 1241 * if we didn't do the snprintf to find out how long arg_num_len was. 1242 */ 1243 static int audit_log_single_execve_arg(struct audit_context *context, 1244 struct audit_buffer **ab, 1245 int arg_num, 1246 size_t *len_sent, 1247 const char __user *p, 1248 char *buf) 1249 { 1250 char arg_num_len_buf[12]; 1251 const char __user *tmp_p = p; 1252 /* how many digits are in arg_num? 5 is the length of ' a=""' */ 1253 size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 5; 1254 size_t len, len_left, to_send; 1255 size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN; 1256 unsigned int i, has_cntl = 0, too_long = 0; 1257 int ret; 1258 1259 /* strnlen_user includes the null we don't want to send */ 1260 len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1; 1261 1262 /* 1263 * We just created this mm, if we can't find the strings 1264 * we just copied into it something is _very_ wrong. Similar 1265 * for strings that are too long, we should not have created 1266 * any. 1267 */ 1268 if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) { 1269 WARN_ON(1); 1270 send_sig(SIGKILL, current, 0); 1271 return -1; 1272 } 1273 1274 /* walk the whole argument looking for non-ascii chars */ 1275 do { 1276 if (len_left > MAX_EXECVE_AUDIT_LEN) 1277 to_send = MAX_EXECVE_AUDIT_LEN; 1278 else 1279 to_send = len_left; 1280 ret = copy_from_user(buf, tmp_p, to_send); 1281 /* 1282 * There is no reason for this copy to be short. We just 1283 * copied them here, and the mm hasn't been exposed to user- 1284 * space yet. 1285 */ 1286 if (ret) { 1287 WARN_ON(1); 1288 send_sig(SIGKILL, current, 0); 1289 return -1; 1290 } 1291 buf[to_send] = '\0'; 1292 has_cntl = audit_string_contains_control(buf, to_send); 1293 if (has_cntl) { 1294 /* 1295 * hex messages get logged as 2 bytes, so we can only 1296 * send half as much in each message 1297 */ 1298 max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2; 1299 break; 1300 } 1301 len_left -= to_send; 1302 tmp_p += to_send; 1303 } while (len_left > 0); 1304 1305 len_left = len; 1306 1307 if (len > max_execve_audit_len) 1308 too_long = 1; 1309 1310 /* rewalk the argument actually logging the message */ 1311 for (i = 0; len_left > 0; i++) { 1312 int room_left; 1313 1314 if (len_left > max_execve_audit_len) 1315 to_send = max_execve_audit_len; 1316 else 1317 to_send = len_left; 1318 1319 /* do we have space left to send this argument in this ab? */ 1320 room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent; 1321 if (has_cntl) 1322 room_left -= (to_send * 2); 1323 else 1324 room_left -= to_send; 1325 if (room_left < 0) { 1326 *len_sent = 0; 1327 audit_log_end(*ab); 1328 *ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE); 1329 if (!*ab) 1330 return 0; 1331 } 1332 1333 /* 1334 * first record needs to say how long the original string was 1335 * so we can be sure nothing was lost. 1336 */ 1337 if ((i == 0) && (too_long)) 1338 audit_log_format(*ab, " a%d_len=%zu", arg_num, 1339 has_cntl ? 2*len : len); 1340 1341 /* 1342 * normally arguments are small enough to fit and we already 1343 * filled buf above when we checked for control characters 1344 * so don't bother with another copy_from_user 1345 */ 1346 if (len >= max_execve_audit_len) 1347 ret = copy_from_user(buf, p, to_send); 1348 else 1349 ret = 0; 1350 if (ret) { 1351 WARN_ON(1); 1352 send_sig(SIGKILL, current, 0); 1353 return -1; 1354 } 1355 buf[to_send] = '\0'; 1356 1357 /* actually log it */ 1358 audit_log_format(*ab, " a%d", arg_num); 1359 if (too_long) 1360 audit_log_format(*ab, "[%d]", i); 1361 audit_log_format(*ab, "="); 1362 if (has_cntl) 1363 audit_log_n_hex(*ab, buf, to_send); 1364 else 1365 audit_log_string(*ab, buf); 1366 1367 p += to_send; 1368 len_left -= to_send; 1369 *len_sent += arg_num_len; 1370 if (has_cntl) 1371 *len_sent += to_send * 2; 1372 else 1373 *len_sent += to_send; 1374 } 1375 /* include the null we didn't log */ 1376 return len + 1; 1377 } 1378 1379 static void audit_log_execve_info(struct audit_context *context, 1380 struct audit_buffer **ab, 1381 struct audit_aux_data_execve *axi) 1382 { 1383 int i, len; 1384 size_t len_sent = 0; 1385 const char __user *p; 1386 char *buf; 1387 1388 if (axi->mm != current->mm) 1389 return; /* execve failed, no additional info */ 1390 1391 p = (const char __user *)axi->mm->arg_start; 1392 1393 audit_log_format(*ab, "argc=%d", axi->argc); 1394 1395 /* 1396 * we need some kernel buffer to hold the userspace args. Just 1397 * allocate one big one rather than allocating one of the right size 1398 * for every single argument inside audit_log_single_execve_arg() 1399 * should be <8k allocation so should be pretty safe. 1400 */ 1401 buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL); 1402 if (!buf) { 1403 audit_panic("out of memory for argv string\n"); 1404 return; 1405 } 1406 1407 for (i = 0; i < axi->argc; i++) { 1408 len = audit_log_single_execve_arg(context, ab, i, 1409 &len_sent, p, buf); 1410 if (len <= 0) 1411 break; 1412 p += len; 1413 } 1414 kfree(buf); 1415 } 1416 1417 static void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap) 1418 { 1419 int i; 1420 1421 audit_log_format(ab, " %s=", prefix); 1422 CAP_FOR_EACH_U32(i) { 1423 audit_log_format(ab, "%08x", cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]); 1424 } 1425 } 1426 1427 static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) 1428 { 1429 kernel_cap_t *perm = &name->fcap.permitted; 1430 kernel_cap_t *inh = &name->fcap.inheritable; 1431 int log = 0; 1432 1433 if (!cap_isclear(*perm)) { 1434 audit_log_cap(ab, "cap_fp", perm); 1435 log = 1; 1436 } 1437 if (!cap_isclear(*inh)) { 1438 audit_log_cap(ab, "cap_fi", inh); 1439 log = 1; 1440 } 1441 1442 if (log) 1443 audit_log_format(ab, " cap_fe=%d cap_fver=%x", name->fcap.fE, name->fcap_ver); 1444 } 1445 1446 static void show_special(struct audit_context *context, int *call_panic) 1447 { 1448 struct audit_buffer *ab; 1449 int i; 1450 1451 ab = audit_log_start(context, GFP_KERNEL, context->type); 1452 if (!ab) 1453 return; 1454 1455 switch (context->type) { 1456 case AUDIT_SOCKETCALL: { 1457 int nargs = context->socketcall.nargs; 1458 audit_log_format(ab, "nargs=%d", nargs); 1459 for (i = 0; i < nargs; i++) 1460 audit_log_format(ab, " a%d=%lx", i, 1461 context->socketcall.args[i]); 1462 break; } 1463 case AUDIT_IPC: { 1464 u32 osid = context->ipc.osid; 1465 1466 audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho", 1467 from_kuid(&init_user_ns, context->ipc.uid), 1468 from_kgid(&init_user_ns, context->ipc.gid), 1469 context->ipc.mode); 1470 if (osid) { 1471 char *ctx = NULL; 1472 u32 len; 1473 if (security_secid_to_secctx(osid, &ctx, &len)) { 1474 audit_log_format(ab, " osid=%u", osid); 1475 *call_panic = 1; 1476 } else { 1477 audit_log_format(ab, " obj=%s", ctx); 1478 security_release_secctx(ctx, len); 1479 } 1480 } 1481 if (context->ipc.has_perm) { 1482 audit_log_end(ab); 1483 ab = audit_log_start(context, GFP_KERNEL, 1484 AUDIT_IPC_SET_PERM); 1485 audit_log_format(ab, 1486 "qbytes=%lx ouid=%u ogid=%u mode=%#ho", 1487 context->ipc.qbytes, 1488 context->ipc.perm_uid, 1489 context->ipc.perm_gid, 1490 context->ipc.perm_mode); 1491 if (!ab) 1492 return; 1493 } 1494 break; } 1495 case AUDIT_MQ_OPEN: { 1496 audit_log_format(ab, 1497 "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld " 1498 "mq_msgsize=%ld mq_curmsgs=%ld", 1499 context->mq_open.oflag, context->mq_open.mode, 1500 context->mq_open.attr.mq_flags, 1501 context->mq_open.attr.mq_maxmsg, 1502 context->mq_open.attr.mq_msgsize, 1503 context->mq_open.attr.mq_curmsgs); 1504 break; } 1505 case AUDIT_MQ_SENDRECV: { 1506 audit_log_format(ab, 1507 "mqdes=%d msg_len=%zd msg_prio=%u " 1508 "abs_timeout_sec=%ld abs_timeout_nsec=%ld", 1509 context->mq_sendrecv.mqdes, 1510 context->mq_sendrecv.msg_len, 1511 context->mq_sendrecv.msg_prio, 1512 context->mq_sendrecv.abs_timeout.tv_sec, 1513 context->mq_sendrecv.abs_timeout.tv_nsec); 1514 break; } 1515 case AUDIT_MQ_NOTIFY: { 1516 audit_log_format(ab, "mqdes=%d sigev_signo=%d", 1517 context->mq_notify.mqdes, 1518 context->mq_notify.sigev_signo); 1519 break; } 1520 case AUDIT_MQ_GETSETATTR: { 1521 struct mq_attr *attr = &context->mq_getsetattr.mqstat; 1522 audit_log_format(ab, 1523 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld " 1524 "mq_curmsgs=%ld ", 1525 context->mq_getsetattr.mqdes, 1526 attr->mq_flags, attr->mq_maxmsg, 1527 attr->mq_msgsize, attr->mq_curmsgs); 1528 break; } 1529 case AUDIT_CAPSET: { 1530 audit_log_format(ab, "pid=%d", context->capset.pid); 1531 audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable); 1532 audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted); 1533 audit_log_cap(ab, "cap_pe", &context->capset.cap.effective); 1534 break; } 1535 case AUDIT_MMAP: { 1536 audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd, 1537 context->mmap.flags); 1538 break; } 1539 } 1540 audit_log_end(ab); 1541 } 1542 1543 static void audit_log_name(struct audit_context *context, struct audit_names *n, 1544 int record_num, int *call_panic) 1545 { 1546 struct audit_buffer *ab; 1547 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH); 1548 if (!ab) 1549 return; /* audit_panic has been called */ 1550 1551 audit_log_format(ab, "item=%d", record_num); 1552 1553 if (n->name) { 1554 switch (n->name_len) { 1555 case AUDIT_NAME_FULL: 1556 /* log the full path */ 1557 audit_log_format(ab, " name="); 1558 audit_log_untrustedstring(ab, n->name); 1559 break; 1560 case 0: 1561 /* name was specified as a relative path and the 1562 * directory component is the cwd */ 1563 audit_log_d_path(ab, " name=", &context->pwd); 1564 break; 1565 default: 1566 /* log the name's directory component */ 1567 audit_log_format(ab, " name="); 1568 audit_log_n_untrustedstring(ab, n->name, 1569 n->name_len); 1570 } 1571 } else 1572 audit_log_format(ab, " name=(null)"); 1573 1574 if (n->ino != (unsigned long)-1) { 1575 audit_log_format(ab, " inode=%lu" 1576 " dev=%02x:%02x mode=%#ho" 1577 " ouid=%u ogid=%u rdev=%02x:%02x", 1578 n->ino, 1579 MAJOR(n->dev), 1580 MINOR(n->dev), 1581 n->mode, 1582 from_kuid(&init_user_ns, n->uid), 1583 from_kgid(&init_user_ns, n->gid), 1584 MAJOR(n->rdev), 1585 MINOR(n->rdev)); 1586 } 1587 if (n->osid != 0) { 1588 char *ctx = NULL; 1589 u32 len; 1590 if (security_secid_to_secctx( 1591 n->osid, &ctx, &len)) { 1592 audit_log_format(ab, " osid=%u", n->osid); 1593 *call_panic = 2; 1594 } else { 1595 audit_log_format(ab, " obj=%s", ctx); 1596 security_release_secctx(ctx, len); 1597 } 1598 } 1599 1600 audit_log_fcaps(ab, n); 1601 1602 audit_log_end(ab); 1603 } 1604 1605 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk) 1606 { 1607 int i, call_panic = 0; 1608 struct audit_buffer *ab; 1609 struct audit_aux_data *aux; 1610 struct audit_names *n; 1611 1612 /* tsk == current */ 1613 context->personality = tsk->personality; 1614 1615 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); 1616 if (!ab) 1617 return; /* audit_panic has been called */ 1618 audit_log_format(ab, "arch=%x syscall=%d", 1619 context->arch, context->major); 1620 if (context->personality != PER_LINUX) 1621 audit_log_format(ab, " per=%lx", context->personality); 1622 if (context->return_valid) 1623 audit_log_format(ab, " success=%s exit=%ld", 1624 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", 1625 context->return_code); 1626 1627 audit_log_format(ab, 1628 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d", 1629 context->argv[0], 1630 context->argv[1], 1631 context->argv[2], 1632 context->argv[3], 1633 context->name_count); 1634 1635 audit_log_task_info(ab, tsk); 1636 audit_log_key(ab, context->filterkey); 1637 audit_log_end(ab); 1638 1639 for (aux = context->aux; aux; aux = aux->next) { 1640 1641 ab = audit_log_start(context, GFP_KERNEL, aux->type); 1642 if (!ab) 1643 continue; /* audit_panic has been called */ 1644 1645 switch (aux->type) { 1646 1647 case AUDIT_EXECVE: { 1648 struct audit_aux_data_execve *axi = (void *)aux; 1649 audit_log_execve_info(context, &ab, axi); 1650 break; } 1651 1652 case AUDIT_BPRM_FCAPS: { 1653 struct audit_aux_data_bprm_fcaps *axs = (void *)aux; 1654 audit_log_format(ab, "fver=%x", axs->fcap_ver); 1655 audit_log_cap(ab, "fp", &axs->fcap.permitted); 1656 audit_log_cap(ab, "fi", &axs->fcap.inheritable); 1657 audit_log_format(ab, " fe=%d", axs->fcap.fE); 1658 audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted); 1659 audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable); 1660 audit_log_cap(ab, "old_pe", &axs->old_pcap.effective); 1661 audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted); 1662 audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable); 1663 audit_log_cap(ab, "new_pe", &axs->new_pcap.effective); 1664 break; } 1665 1666 } 1667 audit_log_end(ab); 1668 } 1669 1670 if (context->type) 1671 show_special(context, &call_panic); 1672 1673 if (context->fds[0] >= 0) { 1674 ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR); 1675 if (ab) { 1676 audit_log_format(ab, "fd0=%d fd1=%d", 1677 context->fds[0], context->fds[1]); 1678 audit_log_end(ab); 1679 } 1680 } 1681 1682 if (context->sockaddr_len) { 1683 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR); 1684 if (ab) { 1685 audit_log_format(ab, "saddr="); 1686 audit_log_n_hex(ab, (void *)context->sockaddr, 1687 context->sockaddr_len); 1688 audit_log_end(ab); 1689 } 1690 } 1691 1692 for (aux = context->aux_pids; aux; aux = aux->next) { 1693 struct audit_aux_data_pids *axs = (void *)aux; 1694 1695 for (i = 0; i < axs->pid_count; i++) 1696 if (audit_log_pid_context(context, axs->target_pid[i], 1697 axs->target_auid[i], 1698 axs->target_uid[i], 1699 axs->target_sessionid[i], 1700 axs->target_sid[i], 1701 axs->target_comm[i])) 1702 call_panic = 1; 1703 } 1704 1705 if (context->target_pid && 1706 audit_log_pid_context(context, context->target_pid, 1707 context->target_auid, context->target_uid, 1708 context->target_sessionid, 1709 context->target_sid, context->target_comm)) 1710 call_panic = 1; 1711 1712 if (context->pwd.dentry && context->pwd.mnt) { 1713 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); 1714 if (ab) { 1715 audit_log_d_path(ab, " cwd=", &context->pwd); 1716 audit_log_end(ab); 1717 } 1718 } 1719 1720 i = 0; 1721 list_for_each_entry(n, &context->names_list, list) 1722 audit_log_name(context, n, i++, &call_panic); 1723 1724 /* Send end of event record to help user space know we are finished */ 1725 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); 1726 if (ab) 1727 audit_log_end(ab); 1728 if (call_panic) 1729 audit_panic("error converting sid to string"); 1730 } 1731 1732 /** 1733 * audit_free - free a per-task audit context 1734 * @tsk: task whose audit context block to free 1735 * 1736 * Called from copy_process and do_exit 1737 */ 1738 void __audit_free(struct task_struct *tsk) 1739 { 1740 struct audit_context *context; 1741 1742 context = audit_get_context(tsk, 0, 0); 1743 if (!context) 1744 return; 1745 1746 /* Check for system calls that do not go through the exit 1747 * function (e.g., exit_group), then free context block. 1748 * We use GFP_ATOMIC here because we might be doing this 1749 * in the context of the idle thread */ 1750 /* that can happen only if we are called from do_exit() */ 1751 if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) 1752 audit_log_exit(context, tsk); 1753 if (!list_empty(&context->killed_trees)) 1754 audit_kill_trees(&context->killed_trees); 1755 1756 audit_free_context(context); 1757 } 1758 1759 /** 1760 * audit_syscall_entry - fill in an audit record at syscall entry 1761 * @arch: architecture type 1762 * @major: major syscall type (function) 1763 * @a1: additional syscall register 1 1764 * @a2: additional syscall register 2 1765 * @a3: additional syscall register 3 1766 * @a4: additional syscall register 4 1767 * 1768 * Fill in audit context at syscall entry. This only happens if the 1769 * audit context was created when the task was created and the state or 1770 * filters demand the audit context be built. If the state from the 1771 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, 1772 * then the record will be written at syscall exit time (otherwise, it 1773 * will only be written if another part of the kernel requests that it 1774 * be written). 1775 */ 1776 void __audit_syscall_entry(int arch, int major, 1777 unsigned long a1, unsigned long a2, 1778 unsigned long a3, unsigned long a4) 1779 { 1780 struct task_struct *tsk = current; 1781 struct audit_context *context = tsk->audit_context; 1782 enum audit_state state; 1783 1784 if (!context) 1785 return; 1786 1787 /* 1788 * This happens only on certain architectures that make system 1789 * calls in kernel_thread via the entry.S interface, instead of 1790 * with direct calls. (If you are porting to a new 1791 * architecture, hitting this condition can indicate that you 1792 * got the _exit/_leave calls backward in entry.S.) 1793 * 1794 * i386 no 1795 * x86_64 no 1796 * ppc64 yes (see arch/powerpc/platforms/iseries/misc.S) 1797 * 1798 * This also happens with vm86 emulation in a non-nested manner 1799 * (entries without exits), so this case must be caught. 1800 */ 1801 if (context->in_syscall) { 1802 struct audit_context *newctx; 1803 1804 #if AUDIT_DEBUG 1805 printk(KERN_ERR 1806 "audit(:%d) pid=%d in syscall=%d;" 1807 " entering syscall=%d\n", 1808 context->serial, tsk->pid, context->major, major); 1809 #endif 1810 newctx = audit_alloc_context(context->state); 1811 if (newctx) { 1812 newctx->previous = context; 1813 context = newctx; 1814 tsk->audit_context = newctx; 1815 } else { 1816 /* If we can't alloc a new context, the best we 1817 * can do is to leak memory (any pending putname 1818 * will be lost). The only other alternative is 1819 * to abandon auditing. */ 1820 audit_zero_context(context, context->state); 1821 } 1822 } 1823 BUG_ON(context->in_syscall || context->name_count); 1824 1825 if (!audit_enabled) 1826 return; 1827 1828 context->arch = arch; 1829 context->major = major; 1830 context->argv[0] = a1; 1831 context->argv[1] = a2; 1832 context->argv[2] = a3; 1833 context->argv[3] = a4; 1834 1835 state = context->state; 1836 context->dummy = !audit_n_rules; 1837 if (!context->dummy && state == AUDIT_BUILD_CONTEXT) { 1838 context->prio = 0; 1839 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]); 1840 } 1841 if (state == AUDIT_DISABLED) 1842 return; 1843 1844 context->serial = 0; 1845 context->ctime = CURRENT_TIME; 1846 context->in_syscall = 1; 1847 context->current_state = state; 1848 context->ppid = 0; 1849 } 1850 1851 /** 1852 * audit_syscall_exit - deallocate audit context after a system call 1853 * @success: success value of the syscall 1854 * @return_code: return value of the syscall 1855 * 1856 * Tear down after system call. If the audit context has been marked as 1857 * auditable (either because of the AUDIT_RECORD_CONTEXT state from 1858 * filtering, or because some other part of the kernel wrote an audit 1859 * message), then write out the syscall information. In call cases, 1860 * free the names stored from getname(). 1861 */ 1862 void __audit_syscall_exit(int success, long return_code) 1863 { 1864 struct task_struct *tsk = current; 1865 struct audit_context *context; 1866 1867 if (success) 1868 success = AUDITSC_SUCCESS; 1869 else 1870 success = AUDITSC_FAILURE; 1871 1872 context = audit_get_context(tsk, success, return_code); 1873 if (!context) 1874 return; 1875 1876 if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) 1877 audit_log_exit(context, tsk); 1878 1879 context->in_syscall = 0; 1880 context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 1881 1882 if (!list_empty(&context->killed_trees)) 1883 audit_kill_trees(&context->killed_trees); 1884 1885 if (context->previous) { 1886 struct audit_context *new_context = context->previous; 1887 context->previous = NULL; 1888 audit_free_context(context); 1889 tsk->audit_context = new_context; 1890 } else { 1891 audit_free_names(context); 1892 unroll_tree_refs(context, NULL, 0); 1893 audit_free_aux(context); 1894 context->aux = NULL; 1895 context->aux_pids = NULL; 1896 context->target_pid = 0; 1897 context->target_sid = 0; 1898 context->sockaddr_len = 0; 1899 context->type = 0; 1900 context->fds[0] = -1; 1901 if (context->state != AUDIT_RECORD_CONTEXT) { 1902 kfree(context->filterkey); 1903 context->filterkey = NULL; 1904 } 1905 tsk->audit_context = context; 1906 } 1907 } 1908 1909 static inline void handle_one(const struct inode *inode) 1910 { 1911 #ifdef CONFIG_AUDIT_TREE 1912 struct audit_context *context; 1913 struct audit_tree_refs *p; 1914 struct audit_chunk *chunk; 1915 int count; 1916 if (likely(hlist_empty(&inode->i_fsnotify_marks))) 1917 return; 1918 context = current->audit_context; 1919 p = context->trees; 1920 count = context->tree_count; 1921 rcu_read_lock(); 1922 chunk = audit_tree_lookup(inode); 1923 rcu_read_unlock(); 1924 if (!chunk) 1925 return; 1926 if (likely(put_tree_ref(context, chunk))) 1927 return; 1928 if (unlikely(!grow_tree_refs(context))) { 1929 printk(KERN_WARNING "out of memory, audit has lost a tree reference\n"); 1930 audit_set_auditable(context); 1931 audit_put_chunk(chunk); 1932 unroll_tree_refs(context, p, count); 1933 return; 1934 } 1935 put_tree_ref(context, chunk); 1936 #endif 1937 } 1938 1939 static void handle_path(const struct dentry *dentry) 1940 { 1941 #ifdef CONFIG_AUDIT_TREE 1942 struct audit_context *context; 1943 struct audit_tree_refs *p; 1944 const struct dentry *d, *parent; 1945 struct audit_chunk *drop; 1946 unsigned long seq; 1947 int count; 1948 1949 context = current->audit_context; 1950 p = context->trees; 1951 count = context->tree_count; 1952 retry: 1953 drop = NULL; 1954 d = dentry; 1955 rcu_read_lock(); 1956 seq = read_seqbegin(&rename_lock); 1957 for(;;) { 1958 struct inode *inode = d->d_inode; 1959 if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) { 1960 struct audit_chunk *chunk; 1961 chunk = audit_tree_lookup(inode); 1962 if (chunk) { 1963 if (unlikely(!put_tree_ref(context, chunk))) { 1964 drop = chunk; 1965 break; 1966 } 1967 } 1968 } 1969 parent = d->d_parent; 1970 if (parent == d) 1971 break; 1972 d = parent; 1973 } 1974 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */ 1975 rcu_read_unlock(); 1976 if (!drop) { 1977 /* just a race with rename */ 1978 unroll_tree_refs(context, p, count); 1979 goto retry; 1980 } 1981 audit_put_chunk(drop); 1982 if (grow_tree_refs(context)) { 1983 /* OK, got more space */ 1984 unroll_tree_refs(context, p, count); 1985 goto retry; 1986 } 1987 /* too bad */ 1988 printk(KERN_WARNING 1989 "out of memory, audit has lost a tree reference\n"); 1990 unroll_tree_refs(context, p, count); 1991 audit_set_auditable(context); 1992 return; 1993 } 1994 rcu_read_unlock(); 1995 #endif 1996 } 1997 1998 static struct audit_names *audit_alloc_name(struct audit_context *context) 1999 { 2000 struct audit_names *aname; 2001 2002 if (context->name_count < AUDIT_NAMES) { 2003 aname = &context->preallocated_names[context->name_count]; 2004 memset(aname, 0, sizeof(*aname)); 2005 } else { 2006 aname = kzalloc(sizeof(*aname), GFP_NOFS); 2007 if (!aname) 2008 return NULL; 2009 aname->should_free = true; 2010 } 2011 2012 aname->ino = (unsigned long)-1; 2013 list_add_tail(&aname->list, &context->names_list); 2014 2015 context->name_count++; 2016 #if AUDIT_DEBUG 2017 context->ino_count++; 2018 #endif 2019 return aname; 2020 } 2021 2022 /** 2023 * audit_getname - add a name to the list 2024 * @name: name to add 2025 * 2026 * Add a name to the list of audit names for this context. 2027 * Called from fs/namei.c:getname(). 2028 */ 2029 void __audit_getname(const char *name) 2030 { 2031 struct audit_context *context = current->audit_context; 2032 struct audit_names *n; 2033 2034 if (!context->in_syscall) { 2035 #if AUDIT_DEBUG == 2 2036 printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n", 2037 __FILE__, __LINE__, context->serial, name); 2038 dump_stack(); 2039 #endif 2040 return; 2041 } 2042 2043 n = audit_alloc_name(context); 2044 if (!n) 2045 return; 2046 2047 n->name = name; 2048 n->name_len = AUDIT_NAME_FULL; 2049 n->name_put = true; 2050 2051 if (!context->pwd.dentry) 2052 get_fs_pwd(current->fs, &context->pwd); 2053 } 2054 2055 /* audit_putname - intercept a putname request 2056 * @name: name to intercept and delay for putname 2057 * 2058 * If we have stored the name from getname in the audit context, 2059 * then we delay the putname until syscall exit. 2060 * Called from include/linux/fs.h:putname(). 2061 */ 2062 void audit_putname(const char *name) 2063 { 2064 struct audit_context *context = current->audit_context; 2065 2066 BUG_ON(!context); 2067 if (!context->in_syscall) { 2068 #if AUDIT_DEBUG == 2 2069 printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n", 2070 __FILE__, __LINE__, context->serial, name); 2071 if (context->name_count) { 2072 struct audit_names *n; 2073 int i; 2074 2075 list_for_each_entry(n, &context->names_list, list) 2076 printk(KERN_ERR "name[%d] = %p = %s\n", i, 2077 n->name, n->name ?: "(null)"); 2078 } 2079 #endif 2080 __putname(name); 2081 } 2082 #if AUDIT_DEBUG 2083 else { 2084 ++context->put_count; 2085 if (context->put_count > context->name_count) { 2086 printk(KERN_ERR "%s:%d(:%d): major=%d" 2087 " in_syscall=%d putname(%p) name_count=%d" 2088 " put_count=%d\n", 2089 __FILE__, __LINE__, 2090 context->serial, context->major, 2091 context->in_syscall, name, context->name_count, 2092 context->put_count); 2093 dump_stack(); 2094 } 2095 } 2096 #endif 2097 } 2098 2099 static inline int audit_copy_fcaps(struct audit_names *name, const struct dentry *dentry) 2100 { 2101 struct cpu_vfs_cap_data caps; 2102 int rc; 2103 2104 if (!dentry) 2105 return 0; 2106 2107 rc = get_vfs_caps_from_disk(dentry, &caps); 2108 if (rc) 2109 return rc; 2110 2111 name->fcap.permitted = caps.permitted; 2112 name->fcap.inheritable = caps.inheritable; 2113 name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 2114 name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; 2115 2116 return 0; 2117 } 2118 2119 2120 /* Copy inode data into an audit_names. */ 2121 static void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, 2122 const struct inode *inode) 2123 { 2124 name->ino = inode->i_ino; 2125 name->dev = inode->i_sb->s_dev; 2126 name->mode = inode->i_mode; 2127 name->uid = inode->i_uid; 2128 name->gid = inode->i_gid; 2129 name->rdev = inode->i_rdev; 2130 security_inode_getsecid(inode, &name->osid); 2131 audit_copy_fcaps(name, dentry); 2132 } 2133 2134 /** 2135 * audit_inode - store the inode and device from a lookup 2136 * @name: name being audited 2137 * @dentry: dentry being audited 2138 * 2139 * Called from fs/namei.c:path_lookup(). 2140 */ 2141 void __audit_inode(const char *name, const struct dentry *dentry) 2142 { 2143 struct audit_context *context = current->audit_context; 2144 const struct inode *inode = dentry->d_inode; 2145 struct audit_names *n; 2146 2147 if (!context->in_syscall) 2148 return; 2149 2150 list_for_each_entry_reverse(n, &context->names_list, list) { 2151 if (n->name && (n->name == name)) 2152 goto out; 2153 } 2154 2155 /* unable to find the name from a previous getname() */ 2156 n = audit_alloc_name(context); 2157 if (!n) 2158 return; 2159 out: 2160 handle_path(dentry); 2161 audit_copy_inode(n, dentry, inode); 2162 } 2163 2164 /** 2165 * audit_inode_child - collect inode info for created/removed objects 2166 * @dentry: dentry being audited 2167 * @parent: inode of dentry parent 2168 * 2169 * For syscalls that create or remove filesystem objects, audit_inode 2170 * can only collect information for the filesystem object's parent. 2171 * This call updates the audit context with the child's information. 2172 * Syscalls that create a new filesystem object must be hooked after 2173 * the object is created. Syscalls that remove a filesystem object 2174 * must be hooked prior, in order to capture the target inode during 2175 * unsuccessful attempts. 2176 */ 2177 void __audit_inode_child(const struct dentry *dentry, 2178 const struct inode *parent) 2179 { 2180 struct audit_context *context = current->audit_context; 2181 const char *found_parent = NULL, *found_child = NULL; 2182 const struct inode *inode = dentry->d_inode; 2183 const char *dname = dentry->d_name.name; 2184 struct audit_names *n; 2185 int dirlen = 0; 2186 2187 if (!context->in_syscall) 2188 return; 2189 2190 if (inode) 2191 handle_one(inode); 2192 2193 /* parent is more likely, look for it first */ 2194 list_for_each_entry(n, &context->names_list, list) { 2195 if (!n->name) 2196 continue; 2197 2198 if (n->ino == parent->i_ino && 2199 !audit_compare_dname_path(dname, n->name, &dirlen)) { 2200 n->name_len = dirlen; /* update parent data in place */ 2201 found_parent = n->name; 2202 goto add_names; 2203 } 2204 } 2205 2206 /* no matching parent, look for matching child */ 2207 list_for_each_entry(n, &context->names_list, list) { 2208 if (!n->name) 2209 continue; 2210 2211 /* strcmp() is the more likely scenario */ 2212 if (!strcmp(dname, n->name) || 2213 !audit_compare_dname_path(dname, n->name, &dirlen)) { 2214 if (inode) 2215 audit_copy_inode(n, NULL, inode); 2216 else 2217 n->ino = (unsigned long)-1; 2218 found_child = n->name; 2219 goto add_names; 2220 } 2221 } 2222 2223 add_names: 2224 if (!found_parent) { 2225 n = audit_alloc_name(context); 2226 if (!n) 2227 return; 2228 audit_copy_inode(n, NULL, parent); 2229 } 2230 2231 if (!found_child) { 2232 n = audit_alloc_name(context); 2233 if (!n) 2234 return; 2235 2236 /* Re-use the name belonging to the slot for a matching parent 2237 * directory. All names for this context are relinquished in 2238 * audit_free_names() */ 2239 if (found_parent) { 2240 n->name = found_parent; 2241 n->name_len = AUDIT_NAME_FULL; 2242 /* don't call __putname() */ 2243 n->name_put = false; 2244 } 2245 2246 if (inode) 2247 audit_copy_inode(n, NULL, inode); 2248 } 2249 } 2250 EXPORT_SYMBOL_GPL(__audit_inode_child); 2251 2252 /** 2253 * auditsc_get_stamp - get local copies of audit_context values 2254 * @ctx: audit_context for the task 2255 * @t: timespec to store time recorded in the audit_context 2256 * @serial: serial value that is recorded in the audit_context 2257 * 2258 * Also sets the context as auditable. 2259 */ 2260 int auditsc_get_stamp(struct audit_context *ctx, 2261 struct timespec *t, unsigned int *serial) 2262 { 2263 if (!ctx->in_syscall) 2264 return 0; 2265 if (!ctx->serial) 2266 ctx->serial = audit_serial(); 2267 t->tv_sec = ctx->ctime.tv_sec; 2268 t->tv_nsec = ctx->ctime.tv_nsec; 2269 *serial = ctx->serial; 2270 if (!ctx->prio) { 2271 ctx->prio = 1; 2272 ctx->current_state = AUDIT_RECORD_CONTEXT; 2273 } 2274 return 1; 2275 } 2276 2277 /* global counter which is incremented every time something logs in */ 2278 static atomic_t session_id = ATOMIC_INIT(0); 2279 2280 /** 2281 * audit_set_loginuid - set current task's audit_context loginuid 2282 * @loginuid: loginuid value 2283 * 2284 * Returns 0. 2285 * 2286 * Called (set) from fs/proc/base.c::proc_loginuid_write(). 2287 */ 2288 int audit_set_loginuid(kuid_t loginuid) 2289 { 2290 struct task_struct *task = current; 2291 struct audit_context *context = task->audit_context; 2292 unsigned int sessionid; 2293 2294 #ifdef CONFIG_AUDIT_LOGINUID_IMMUTABLE 2295 if (uid_valid(task->loginuid)) 2296 return -EPERM; 2297 #else /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */ 2298 if (!capable(CAP_AUDIT_CONTROL)) 2299 return -EPERM; 2300 #endif /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */ 2301 2302 sessionid = atomic_inc_return(&session_id); 2303 if (context && context->in_syscall) { 2304 struct audit_buffer *ab; 2305 2306 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); 2307 if (ab) { 2308 audit_log_format(ab, "login pid=%d uid=%u " 2309 "old auid=%u new auid=%u" 2310 " old ses=%u new ses=%u", 2311 task->pid, 2312 from_kuid(&init_user_ns, task_uid(task)), 2313 from_kuid(&init_user_ns, task->loginuid), 2314 from_kuid(&init_user_ns, loginuid), 2315 task->sessionid, sessionid); 2316 audit_log_end(ab); 2317 } 2318 } 2319 task->sessionid = sessionid; 2320 task->loginuid = loginuid; 2321 return 0; 2322 } 2323 2324 /** 2325 * __audit_mq_open - record audit data for a POSIX MQ open 2326 * @oflag: open flag 2327 * @mode: mode bits 2328 * @attr: queue attributes 2329 * 2330 */ 2331 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr) 2332 { 2333 struct audit_context *context = current->audit_context; 2334 2335 if (attr) 2336 memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr)); 2337 else 2338 memset(&context->mq_open.attr, 0, sizeof(struct mq_attr)); 2339 2340 context->mq_open.oflag = oflag; 2341 context->mq_open.mode = mode; 2342 2343 context->type = AUDIT_MQ_OPEN; 2344 } 2345 2346 /** 2347 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive 2348 * @mqdes: MQ descriptor 2349 * @msg_len: Message length 2350 * @msg_prio: Message priority 2351 * @abs_timeout: Message timeout in absolute time 2352 * 2353 */ 2354 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, 2355 const struct timespec *abs_timeout) 2356 { 2357 struct audit_context *context = current->audit_context; 2358 struct timespec *p = &context->mq_sendrecv.abs_timeout; 2359 2360 if (abs_timeout) 2361 memcpy(p, abs_timeout, sizeof(struct timespec)); 2362 else 2363 memset(p, 0, sizeof(struct timespec)); 2364 2365 context->mq_sendrecv.mqdes = mqdes; 2366 context->mq_sendrecv.msg_len = msg_len; 2367 context->mq_sendrecv.msg_prio = msg_prio; 2368 2369 context->type = AUDIT_MQ_SENDRECV; 2370 } 2371 2372 /** 2373 * __audit_mq_notify - record audit data for a POSIX MQ notify 2374 * @mqdes: MQ descriptor 2375 * @notification: Notification event 2376 * 2377 */ 2378 2379 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification) 2380 { 2381 struct audit_context *context = current->audit_context; 2382 2383 if (notification) 2384 context->mq_notify.sigev_signo = notification->sigev_signo; 2385 else 2386 context->mq_notify.sigev_signo = 0; 2387 2388 context->mq_notify.mqdes = mqdes; 2389 context->type = AUDIT_MQ_NOTIFY; 2390 } 2391 2392 /** 2393 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute 2394 * @mqdes: MQ descriptor 2395 * @mqstat: MQ flags 2396 * 2397 */ 2398 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) 2399 { 2400 struct audit_context *context = current->audit_context; 2401 context->mq_getsetattr.mqdes = mqdes; 2402 context->mq_getsetattr.mqstat = *mqstat; 2403 context->type = AUDIT_MQ_GETSETATTR; 2404 } 2405 2406 /** 2407 * audit_ipc_obj - record audit data for ipc object 2408 * @ipcp: ipc permissions 2409 * 2410 */ 2411 void __audit_ipc_obj(struct kern_ipc_perm *ipcp) 2412 { 2413 struct audit_context *context = current->audit_context; 2414 context->ipc.uid = ipcp->uid; 2415 context->ipc.gid = ipcp->gid; 2416 context->ipc.mode = ipcp->mode; 2417 context->ipc.has_perm = 0; 2418 security_ipc_getsecid(ipcp, &context->ipc.osid); 2419 context->type = AUDIT_IPC; 2420 } 2421 2422 /** 2423 * audit_ipc_set_perm - record audit data for new ipc permissions 2424 * @qbytes: msgq bytes 2425 * @uid: msgq user id 2426 * @gid: msgq group id 2427 * @mode: msgq mode (permissions) 2428 * 2429 * Called only after audit_ipc_obj(). 2430 */ 2431 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode) 2432 { 2433 struct audit_context *context = current->audit_context; 2434 2435 context->ipc.qbytes = qbytes; 2436 context->ipc.perm_uid = uid; 2437 context->ipc.perm_gid = gid; 2438 context->ipc.perm_mode = mode; 2439 context->ipc.has_perm = 1; 2440 } 2441 2442 int __audit_bprm(struct linux_binprm *bprm) 2443 { 2444 struct audit_aux_data_execve *ax; 2445 struct audit_context *context = current->audit_context; 2446 2447 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2448 if (!ax) 2449 return -ENOMEM; 2450 2451 ax->argc = bprm->argc; 2452 ax->envc = bprm->envc; 2453 ax->mm = bprm->mm; 2454 ax->d.type = AUDIT_EXECVE; 2455 ax->d.next = context->aux; 2456 context->aux = (void *)ax; 2457 return 0; 2458 } 2459 2460 2461 /** 2462 * audit_socketcall - record audit data for sys_socketcall 2463 * @nargs: number of args 2464 * @args: args array 2465 * 2466 */ 2467 void __audit_socketcall(int nargs, unsigned long *args) 2468 { 2469 struct audit_context *context = current->audit_context; 2470 2471 context->type = AUDIT_SOCKETCALL; 2472 context->socketcall.nargs = nargs; 2473 memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long)); 2474 } 2475 2476 /** 2477 * __audit_fd_pair - record audit data for pipe and socketpair 2478 * @fd1: the first file descriptor 2479 * @fd2: the second file descriptor 2480 * 2481 */ 2482 void __audit_fd_pair(int fd1, int fd2) 2483 { 2484 struct audit_context *context = current->audit_context; 2485 context->fds[0] = fd1; 2486 context->fds[1] = fd2; 2487 } 2488 2489 /** 2490 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto 2491 * @len: data length in user space 2492 * @a: data address in kernel space 2493 * 2494 * Returns 0 for success or NULL context or < 0 on error. 2495 */ 2496 int __audit_sockaddr(int len, void *a) 2497 { 2498 struct audit_context *context = current->audit_context; 2499 2500 if (!context->sockaddr) { 2501 void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL); 2502 if (!p) 2503 return -ENOMEM; 2504 context->sockaddr = p; 2505 } 2506 2507 context->sockaddr_len = len; 2508 memcpy(context->sockaddr, a, len); 2509 return 0; 2510 } 2511 2512 void __audit_ptrace(struct task_struct *t) 2513 { 2514 struct audit_context *context = current->audit_context; 2515 2516 context->target_pid = t->pid; 2517 context->target_auid = audit_get_loginuid(t); 2518 context->target_uid = task_uid(t); 2519 context->target_sessionid = audit_get_sessionid(t); 2520 security_task_getsecid(t, &context->target_sid); 2521 memcpy(context->target_comm, t->comm, TASK_COMM_LEN); 2522 } 2523 2524 /** 2525 * audit_signal_info - record signal info for shutting down audit subsystem 2526 * @sig: signal value 2527 * @t: task being signaled 2528 * 2529 * If the audit subsystem is being terminated, record the task (pid) 2530 * and uid that is doing that. 2531 */ 2532 int __audit_signal_info(int sig, struct task_struct *t) 2533 { 2534 struct audit_aux_data_pids *axp; 2535 struct task_struct *tsk = current; 2536 struct audit_context *ctx = tsk->audit_context; 2537 kuid_t uid = current_uid(), t_uid = task_uid(t); 2538 2539 if (audit_pid && t->tgid == audit_pid) { 2540 if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) { 2541 audit_sig_pid = tsk->pid; 2542 if (uid_valid(tsk->loginuid)) 2543 audit_sig_uid = tsk->loginuid; 2544 else 2545 audit_sig_uid = uid; 2546 security_task_getsecid(tsk, &audit_sig_sid); 2547 } 2548 if (!audit_signals || audit_dummy_context()) 2549 return 0; 2550 } 2551 2552 /* optimize the common case by putting first signal recipient directly 2553 * in audit_context */ 2554 if (!ctx->target_pid) { 2555 ctx->target_pid = t->tgid; 2556 ctx->target_auid = audit_get_loginuid(t); 2557 ctx->target_uid = t_uid; 2558 ctx->target_sessionid = audit_get_sessionid(t); 2559 security_task_getsecid(t, &ctx->target_sid); 2560 memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); 2561 return 0; 2562 } 2563 2564 axp = (void *)ctx->aux_pids; 2565 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { 2566 axp = kzalloc(sizeof(*axp), GFP_ATOMIC); 2567 if (!axp) 2568 return -ENOMEM; 2569 2570 axp->d.type = AUDIT_OBJ_PID; 2571 axp->d.next = ctx->aux_pids; 2572 ctx->aux_pids = (void *)axp; 2573 } 2574 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); 2575 2576 axp->target_pid[axp->pid_count] = t->tgid; 2577 axp->target_auid[axp->pid_count] = audit_get_loginuid(t); 2578 axp->target_uid[axp->pid_count] = t_uid; 2579 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); 2580 security_task_getsecid(t, &axp->target_sid[axp->pid_count]); 2581 memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); 2582 axp->pid_count++; 2583 2584 return 0; 2585 } 2586 2587 /** 2588 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps 2589 * @bprm: pointer to the bprm being processed 2590 * @new: the proposed new credentials 2591 * @old: the old credentials 2592 * 2593 * Simply check if the proc already has the caps given by the file and if not 2594 * store the priv escalation info for later auditing at the end of the syscall 2595 * 2596 * -Eric 2597 */ 2598 int __audit_log_bprm_fcaps(struct linux_binprm *bprm, 2599 const struct cred *new, const struct cred *old) 2600 { 2601 struct audit_aux_data_bprm_fcaps *ax; 2602 struct audit_context *context = current->audit_context; 2603 struct cpu_vfs_cap_data vcaps; 2604 struct dentry *dentry; 2605 2606 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2607 if (!ax) 2608 return -ENOMEM; 2609 2610 ax->d.type = AUDIT_BPRM_FCAPS; 2611 ax->d.next = context->aux; 2612 context->aux = (void *)ax; 2613 2614 dentry = dget(bprm->file->f_dentry); 2615 get_vfs_caps_from_disk(dentry, &vcaps); 2616 dput(dentry); 2617 2618 ax->fcap.permitted = vcaps.permitted; 2619 ax->fcap.inheritable = vcaps.inheritable; 2620 ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 2621 ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; 2622 2623 ax->old_pcap.permitted = old->cap_permitted; 2624 ax->old_pcap.inheritable = old->cap_inheritable; 2625 ax->old_pcap.effective = old->cap_effective; 2626 2627 ax->new_pcap.permitted = new->cap_permitted; 2628 ax->new_pcap.inheritable = new->cap_inheritable; 2629 ax->new_pcap.effective = new->cap_effective; 2630 return 0; 2631 } 2632 2633 /** 2634 * __audit_log_capset - store information about the arguments to the capset syscall 2635 * @pid: target pid of the capset call 2636 * @new: the new credentials 2637 * @old: the old (current) credentials 2638 * 2639 * Record the aguments userspace sent to sys_capset for later printing by the 2640 * audit system if applicable 2641 */ 2642 void __audit_log_capset(pid_t pid, 2643 const struct cred *new, const struct cred *old) 2644 { 2645 struct audit_context *context = current->audit_context; 2646 context->capset.pid = pid; 2647 context->capset.cap.effective = new->cap_effective; 2648 context->capset.cap.inheritable = new->cap_effective; 2649 context->capset.cap.permitted = new->cap_permitted; 2650 context->type = AUDIT_CAPSET; 2651 } 2652 2653 void __audit_mmap_fd(int fd, int flags) 2654 { 2655 struct audit_context *context = current->audit_context; 2656 context->mmap.fd = fd; 2657 context->mmap.flags = flags; 2658 context->type = AUDIT_MMAP; 2659 } 2660 2661 static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr) 2662 { 2663 kuid_t auid, uid; 2664 kgid_t gid; 2665 unsigned int sessionid; 2666 2667 auid = audit_get_loginuid(current); 2668 sessionid = audit_get_sessionid(current); 2669 current_uid_gid(&uid, &gid); 2670 2671 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", 2672 from_kuid(&init_user_ns, auid), 2673 from_kuid(&init_user_ns, uid), 2674 from_kgid(&init_user_ns, gid), 2675 sessionid); 2676 audit_log_task_context(ab); 2677 audit_log_format(ab, " pid=%d comm=", current->pid); 2678 audit_log_untrustedstring(ab, current->comm); 2679 audit_log_format(ab, " reason="); 2680 audit_log_string(ab, reason); 2681 audit_log_format(ab, " sig=%ld", signr); 2682 } 2683 /** 2684 * audit_core_dumps - record information about processes that end abnormally 2685 * @signr: signal value 2686 * 2687 * If a process ends with a core dump, something fishy is going on and we 2688 * should record the event for investigation. 2689 */ 2690 void audit_core_dumps(long signr) 2691 { 2692 struct audit_buffer *ab; 2693 2694 if (!audit_enabled) 2695 return; 2696 2697 if (signr == SIGQUIT) /* don't care for those */ 2698 return; 2699 2700 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); 2701 audit_log_abend(ab, "memory violation", signr); 2702 audit_log_end(ab); 2703 } 2704 2705 void __audit_seccomp(unsigned long syscall, long signr, int code) 2706 { 2707 struct audit_buffer *ab; 2708 2709 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); 2710 audit_log_abend(ab, "seccomp", signr); 2711 audit_log_format(ab, " syscall=%ld", syscall); 2712 audit_log_format(ab, " compat=%d", is_compat_task()); 2713 audit_log_format(ab, " ip=0x%lx", KSTK_EIP(current)); 2714 audit_log_format(ab, " code=0x%x", code); 2715 audit_log_end(ab); 2716 } 2717 2718 struct list_head *audit_killed_trees(void) 2719 { 2720 struct audit_context *ctx = current->audit_context; 2721 if (likely(!ctx || !ctx->in_syscall)) 2722 return NULL; 2723 return &ctx->killed_trees; 2724 } 2725