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 /* no execve audit message should be longer than this (userspace limits) */ 85 #define MAX_EXECVE_AUDIT_LEN 7500 86 87 /* number of audit rules */ 88 int audit_n_rules; 89 90 /* determines whether we collect data for signals sent */ 91 int audit_signals; 92 93 struct audit_cap_data { 94 kernel_cap_t permitted; 95 kernel_cap_t inheritable; 96 union { 97 unsigned int fE; /* effective bit of a file capability */ 98 kernel_cap_t effective; /* effective set of a process */ 99 }; 100 }; 101 102 /* When fs/namei.c:getname() is called, we store the pointer in name and 103 * we don't let putname() free it (instead we free all of the saved 104 * pointers at syscall exit time). 105 * 106 * Further, in fs/namei.c:path_lookup() we store the inode and device. 107 */ 108 struct audit_names { 109 struct list_head list; /* audit_context->names_list */ 110 struct filename *name; 111 unsigned long ino; 112 dev_t dev; 113 umode_t mode; 114 kuid_t uid; 115 kgid_t gid; 116 dev_t rdev; 117 u32 osid; 118 struct audit_cap_data fcap; 119 unsigned int fcap_ver; 120 int name_len; /* number of name's characters to log */ 121 unsigned char type; /* record type */ 122 bool name_put; /* call __putname() for this name */ 123 /* 124 * This was an allocated audit_names and not from the array of 125 * names allocated in the task audit context. Thus this name 126 * should be freed on syscall exit 127 */ 128 bool should_free; 129 }; 130 131 struct audit_aux_data { 132 struct audit_aux_data *next; 133 int type; 134 }; 135 136 #define AUDIT_AUX_IPCPERM 0 137 138 /* Number of target pids per aux struct. */ 139 #define AUDIT_AUX_PIDS 16 140 141 struct audit_aux_data_execve { 142 struct audit_aux_data d; 143 int argc; 144 int envc; 145 struct mm_struct *mm; 146 }; 147 148 struct audit_aux_data_pids { 149 struct audit_aux_data d; 150 pid_t target_pid[AUDIT_AUX_PIDS]; 151 kuid_t target_auid[AUDIT_AUX_PIDS]; 152 kuid_t target_uid[AUDIT_AUX_PIDS]; 153 unsigned int target_sessionid[AUDIT_AUX_PIDS]; 154 u32 target_sid[AUDIT_AUX_PIDS]; 155 char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN]; 156 int pid_count; 157 }; 158 159 struct audit_aux_data_bprm_fcaps { 160 struct audit_aux_data d; 161 struct audit_cap_data fcap; 162 unsigned int fcap_ver; 163 struct audit_cap_data old_pcap; 164 struct audit_cap_data new_pcap; 165 }; 166 167 struct audit_aux_data_capset { 168 struct audit_aux_data d; 169 pid_t pid; 170 struct audit_cap_data cap; 171 }; 172 173 struct audit_tree_refs { 174 struct audit_tree_refs *next; 175 struct audit_chunk *c[31]; 176 }; 177 178 /* The per-task audit context. */ 179 struct audit_context { 180 int dummy; /* must be the first element */ 181 int in_syscall; /* 1 if task is in a syscall */ 182 enum audit_state state, current_state; 183 unsigned int serial; /* serial number for record */ 184 int major; /* syscall number */ 185 struct timespec ctime; /* time of syscall entry */ 186 unsigned long argv[4]; /* syscall arguments */ 187 long return_code;/* syscall return code */ 188 u64 prio; 189 int return_valid; /* return code is valid */ 190 /* 191 * The names_list is the list of all audit_names collected during this 192 * syscall. The first AUDIT_NAMES entries in the names_list will 193 * actually be from the preallocated_names array for performance 194 * reasons. Except during allocation they should never be referenced 195 * through the preallocated_names array and should only be found/used 196 * by running the names_list. 197 */ 198 struct audit_names preallocated_names[AUDIT_NAMES]; 199 int name_count; /* total records in names_list */ 200 struct list_head names_list; /* anchor for struct audit_names->list */ 201 char * filterkey; /* key for rule that triggered record */ 202 struct path pwd; 203 struct audit_aux_data *aux; 204 struct audit_aux_data *aux_pids; 205 struct sockaddr_storage *sockaddr; 206 size_t sockaddr_len; 207 /* Save things to print about task_struct */ 208 pid_t pid, ppid; 209 kuid_t uid, euid, suid, fsuid; 210 kgid_t gid, egid, sgid, fsgid; 211 unsigned long personality; 212 int arch; 213 214 pid_t target_pid; 215 kuid_t target_auid; 216 kuid_t target_uid; 217 unsigned int target_sessionid; 218 u32 target_sid; 219 char target_comm[TASK_COMM_LEN]; 220 221 struct audit_tree_refs *trees, *first_trees; 222 struct list_head killed_trees; 223 int tree_count; 224 225 int type; 226 union { 227 struct { 228 int nargs; 229 long args[6]; 230 } socketcall; 231 struct { 232 kuid_t uid; 233 kgid_t gid; 234 umode_t mode; 235 u32 osid; 236 int has_perm; 237 uid_t perm_uid; 238 gid_t perm_gid; 239 umode_t perm_mode; 240 unsigned long qbytes; 241 } ipc; 242 struct { 243 mqd_t mqdes; 244 struct mq_attr mqstat; 245 } mq_getsetattr; 246 struct { 247 mqd_t mqdes; 248 int sigev_signo; 249 } mq_notify; 250 struct { 251 mqd_t mqdes; 252 size_t msg_len; 253 unsigned int msg_prio; 254 struct timespec abs_timeout; 255 } mq_sendrecv; 256 struct { 257 int oflag; 258 umode_t mode; 259 struct mq_attr attr; 260 } mq_open; 261 struct { 262 pid_t pid; 263 struct audit_cap_data cap; 264 } capset; 265 struct { 266 int fd; 267 int flags; 268 } mmap; 269 }; 270 int fds[2]; 271 272 #if AUDIT_DEBUG 273 int put_count; 274 int ino_count; 275 #endif 276 }; 277 278 static inline int open_arg(int flags, int mask) 279 { 280 int n = ACC_MODE(flags); 281 if (flags & (O_TRUNC | O_CREAT)) 282 n |= AUDIT_PERM_WRITE; 283 return n & mask; 284 } 285 286 static int audit_match_perm(struct audit_context *ctx, int mask) 287 { 288 unsigned n; 289 if (unlikely(!ctx)) 290 return 0; 291 n = ctx->major; 292 293 switch (audit_classify_syscall(ctx->arch, n)) { 294 case 0: /* native */ 295 if ((mask & AUDIT_PERM_WRITE) && 296 audit_match_class(AUDIT_CLASS_WRITE, n)) 297 return 1; 298 if ((mask & AUDIT_PERM_READ) && 299 audit_match_class(AUDIT_CLASS_READ, n)) 300 return 1; 301 if ((mask & AUDIT_PERM_ATTR) && 302 audit_match_class(AUDIT_CLASS_CHATTR, n)) 303 return 1; 304 return 0; 305 case 1: /* 32bit on biarch */ 306 if ((mask & AUDIT_PERM_WRITE) && 307 audit_match_class(AUDIT_CLASS_WRITE_32, n)) 308 return 1; 309 if ((mask & AUDIT_PERM_READ) && 310 audit_match_class(AUDIT_CLASS_READ_32, n)) 311 return 1; 312 if ((mask & AUDIT_PERM_ATTR) && 313 audit_match_class(AUDIT_CLASS_CHATTR_32, n)) 314 return 1; 315 return 0; 316 case 2: /* open */ 317 return mask & ACC_MODE(ctx->argv[1]); 318 case 3: /* openat */ 319 return mask & ACC_MODE(ctx->argv[2]); 320 case 4: /* socketcall */ 321 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); 322 case 5: /* execve */ 323 return mask & AUDIT_PERM_EXEC; 324 default: 325 return 0; 326 } 327 } 328 329 static int audit_match_filetype(struct audit_context *ctx, int val) 330 { 331 struct audit_names *n; 332 umode_t mode = (umode_t)val; 333 334 if (unlikely(!ctx)) 335 return 0; 336 337 list_for_each_entry(n, &ctx->names_list, list) { 338 if ((n->ino != -1) && 339 ((n->mode & S_IFMT) == mode)) 340 return 1; 341 } 342 343 return 0; 344 } 345 346 /* 347 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *; 348 * ->first_trees points to its beginning, ->trees - to the current end of data. 349 * ->tree_count is the number of free entries in array pointed to by ->trees. 350 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL, 351 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously, 352 * it's going to remain 1-element for almost any setup) until we free context itself. 353 * References in it _are_ dropped - at the same time we free/drop aux stuff. 354 */ 355 356 #ifdef CONFIG_AUDIT_TREE 357 static void audit_set_auditable(struct audit_context *ctx) 358 { 359 if (!ctx->prio) { 360 ctx->prio = 1; 361 ctx->current_state = AUDIT_RECORD_CONTEXT; 362 } 363 } 364 365 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk) 366 { 367 struct audit_tree_refs *p = ctx->trees; 368 int left = ctx->tree_count; 369 if (likely(left)) { 370 p->c[--left] = chunk; 371 ctx->tree_count = left; 372 return 1; 373 } 374 if (!p) 375 return 0; 376 p = p->next; 377 if (p) { 378 p->c[30] = chunk; 379 ctx->trees = p; 380 ctx->tree_count = 30; 381 return 1; 382 } 383 return 0; 384 } 385 386 static int grow_tree_refs(struct audit_context *ctx) 387 { 388 struct audit_tree_refs *p = ctx->trees; 389 ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL); 390 if (!ctx->trees) { 391 ctx->trees = p; 392 return 0; 393 } 394 if (p) 395 p->next = ctx->trees; 396 else 397 ctx->first_trees = ctx->trees; 398 ctx->tree_count = 31; 399 return 1; 400 } 401 #endif 402 403 static void unroll_tree_refs(struct audit_context *ctx, 404 struct audit_tree_refs *p, int count) 405 { 406 #ifdef CONFIG_AUDIT_TREE 407 struct audit_tree_refs *q; 408 int n; 409 if (!p) { 410 /* we started with empty chain */ 411 p = ctx->first_trees; 412 count = 31; 413 /* if the very first allocation has failed, nothing to do */ 414 if (!p) 415 return; 416 } 417 n = count; 418 for (q = p; q != ctx->trees; q = q->next, n = 31) { 419 while (n--) { 420 audit_put_chunk(q->c[n]); 421 q->c[n] = NULL; 422 } 423 } 424 while (n-- > ctx->tree_count) { 425 audit_put_chunk(q->c[n]); 426 q->c[n] = NULL; 427 } 428 ctx->trees = p; 429 ctx->tree_count = count; 430 #endif 431 } 432 433 static void free_tree_refs(struct audit_context *ctx) 434 { 435 struct audit_tree_refs *p, *q; 436 for (p = ctx->first_trees; p; p = q) { 437 q = p->next; 438 kfree(p); 439 } 440 } 441 442 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree) 443 { 444 #ifdef CONFIG_AUDIT_TREE 445 struct audit_tree_refs *p; 446 int n; 447 if (!tree) 448 return 0; 449 /* full ones */ 450 for (p = ctx->first_trees; p != ctx->trees; p = p->next) { 451 for (n = 0; n < 31; n++) 452 if (audit_tree_match(p->c[n], tree)) 453 return 1; 454 } 455 /* partial */ 456 if (p) { 457 for (n = ctx->tree_count; n < 31; n++) 458 if (audit_tree_match(p->c[n], tree)) 459 return 1; 460 } 461 #endif 462 return 0; 463 } 464 465 static int audit_compare_uid(kuid_t uid, 466 struct audit_names *name, 467 struct audit_field *f, 468 struct audit_context *ctx) 469 { 470 struct audit_names *n; 471 int rc; 472 473 if (name) { 474 rc = audit_uid_comparator(uid, f->op, name->uid); 475 if (rc) 476 return rc; 477 } 478 479 if (ctx) { 480 list_for_each_entry(n, &ctx->names_list, list) { 481 rc = audit_uid_comparator(uid, f->op, n->uid); 482 if (rc) 483 return rc; 484 } 485 } 486 return 0; 487 } 488 489 static int audit_compare_gid(kgid_t gid, 490 struct audit_names *name, 491 struct audit_field *f, 492 struct audit_context *ctx) 493 { 494 struct audit_names *n; 495 int rc; 496 497 if (name) { 498 rc = audit_gid_comparator(gid, f->op, name->gid); 499 if (rc) 500 return rc; 501 } 502 503 if (ctx) { 504 list_for_each_entry(n, &ctx->names_list, list) { 505 rc = audit_gid_comparator(gid, f->op, n->gid); 506 if (rc) 507 return rc; 508 } 509 } 510 return 0; 511 } 512 513 static int audit_field_compare(struct task_struct *tsk, 514 const struct cred *cred, 515 struct audit_field *f, 516 struct audit_context *ctx, 517 struct audit_names *name) 518 { 519 switch (f->val) { 520 /* process to file object comparisons */ 521 case AUDIT_COMPARE_UID_TO_OBJ_UID: 522 return audit_compare_uid(cred->uid, name, f, ctx); 523 case AUDIT_COMPARE_GID_TO_OBJ_GID: 524 return audit_compare_gid(cred->gid, name, f, ctx); 525 case AUDIT_COMPARE_EUID_TO_OBJ_UID: 526 return audit_compare_uid(cred->euid, name, f, ctx); 527 case AUDIT_COMPARE_EGID_TO_OBJ_GID: 528 return audit_compare_gid(cred->egid, name, f, ctx); 529 case AUDIT_COMPARE_AUID_TO_OBJ_UID: 530 return audit_compare_uid(tsk->loginuid, name, f, ctx); 531 case AUDIT_COMPARE_SUID_TO_OBJ_UID: 532 return audit_compare_uid(cred->suid, name, f, ctx); 533 case AUDIT_COMPARE_SGID_TO_OBJ_GID: 534 return audit_compare_gid(cred->sgid, name, f, ctx); 535 case AUDIT_COMPARE_FSUID_TO_OBJ_UID: 536 return audit_compare_uid(cred->fsuid, name, f, ctx); 537 case AUDIT_COMPARE_FSGID_TO_OBJ_GID: 538 return audit_compare_gid(cred->fsgid, name, f, ctx); 539 /* uid comparisons */ 540 case AUDIT_COMPARE_UID_TO_AUID: 541 return audit_uid_comparator(cred->uid, f->op, tsk->loginuid); 542 case AUDIT_COMPARE_UID_TO_EUID: 543 return audit_uid_comparator(cred->uid, f->op, cred->euid); 544 case AUDIT_COMPARE_UID_TO_SUID: 545 return audit_uid_comparator(cred->uid, f->op, cred->suid); 546 case AUDIT_COMPARE_UID_TO_FSUID: 547 return audit_uid_comparator(cred->uid, f->op, cred->fsuid); 548 /* auid comparisons */ 549 case AUDIT_COMPARE_AUID_TO_EUID: 550 return audit_uid_comparator(tsk->loginuid, f->op, cred->euid); 551 case AUDIT_COMPARE_AUID_TO_SUID: 552 return audit_uid_comparator(tsk->loginuid, f->op, cred->suid); 553 case AUDIT_COMPARE_AUID_TO_FSUID: 554 return audit_uid_comparator(tsk->loginuid, f->op, cred->fsuid); 555 /* euid comparisons */ 556 case AUDIT_COMPARE_EUID_TO_SUID: 557 return audit_uid_comparator(cred->euid, f->op, cred->suid); 558 case AUDIT_COMPARE_EUID_TO_FSUID: 559 return audit_uid_comparator(cred->euid, f->op, cred->fsuid); 560 /* suid comparisons */ 561 case AUDIT_COMPARE_SUID_TO_FSUID: 562 return audit_uid_comparator(cred->suid, f->op, cred->fsuid); 563 /* gid comparisons */ 564 case AUDIT_COMPARE_GID_TO_EGID: 565 return audit_gid_comparator(cred->gid, f->op, cred->egid); 566 case AUDIT_COMPARE_GID_TO_SGID: 567 return audit_gid_comparator(cred->gid, f->op, cred->sgid); 568 case AUDIT_COMPARE_GID_TO_FSGID: 569 return audit_gid_comparator(cred->gid, f->op, cred->fsgid); 570 /* egid comparisons */ 571 case AUDIT_COMPARE_EGID_TO_SGID: 572 return audit_gid_comparator(cred->egid, f->op, cred->sgid); 573 case AUDIT_COMPARE_EGID_TO_FSGID: 574 return audit_gid_comparator(cred->egid, f->op, cred->fsgid); 575 /* sgid comparison */ 576 case AUDIT_COMPARE_SGID_TO_FSGID: 577 return audit_gid_comparator(cred->sgid, f->op, cred->fsgid); 578 default: 579 WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n"); 580 return 0; 581 } 582 return 0; 583 } 584 585 /* Determine if any context name data matches a rule's watch data */ 586 /* Compare a task_struct with an audit_rule. Return 1 on match, 0 587 * otherwise. 588 * 589 * If task_creation is true, this is an explicit indication that we are 590 * filtering a task rule at task creation time. This and tsk == current are 591 * the only situations where tsk->cred may be accessed without an rcu read lock. 592 */ 593 static int audit_filter_rules(struct task_struct *tsk, 594 struct audit_krule *rule, 595 struct audit_context *ctx, 596 struct audit_names *name, 597 enum audit_state *state, 598 bool task_creation) 599 { 600 const struct cred *cred; 601 int i, need_sid = 1; 602 u32 sid; 603 604 cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation); 605 606 for (i = 0; i < rule->field_count; i++) { 607 struct audit_field *f = &rule->fields[i]; 608 struct audit_names *n; 609 int result = 0; 610 611 switch (f->type) { 612 case AUDIT_PID: 613 result = audit_comparator(tsk->pid, f->op, f->val); 614 break; 615 case AUDIT_PPID: 616 if (ctx) { 617 if (!ctx->ppid) 618 ctx->ppid = sys_getppid(); 619 result = audit_comparator(ctx->ppid, f->op, f->val); 620 } 621 break; 622 case AUDIT_UID: 623 result = audit_uid_comparator(cred->uid, f->op, f->uid); 624 break; 625 case AUDIT_EUID: 626 result = audit_uid_comparator(cred->euid, f->op, f->uid); 627 break; 628 case AUDIT_SUID: 629 result = audit_uid_comparator(cred->suid, f->op, f->uid); 630 break; 631 case AUDIT_FSUID: 632 result = audit_uid_comparator(cred->fsuid, f->op, f->uid); 633 break; 634 case AUDIT_GID: 635 result = audit_gid_comparator(cred->gid, f->op, f->gid); 636 break; 637 case AUDIT_EGID: 638 result = audit_gid_comparator(cred->egid, f->op, f->gid); 639 break; 640 case AUDIT_SGID: 641 result = audit_gid_comparator(cred->sgid, f->op, f->gid); 642 break; 643 case AUDIT_FSGID: 644 result = audit_gid_comparator(cred->fsgid, f->op, f->gid); 645 break; 646 case AUDIT_PERS: 647 result = audit_comparator(tsk->personality, f->op, f->val); 648 break; 649 case AUDIT_ARCH: 650 if (ctx) 651 result = audit_comparator(ctx->arch, f->op, f->val); 652 break; 653 654 case AUDIT_EXIT: 655 if (ctx && ctx->return_valid) 656 result = audit_comparator(ctx->return_code, f->op, f->val); 657 break; 658 case AUDIT_SUCCESS: 659 if (ctx && ctx->return_valid) { 660 if (f->val) 661 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS); 662 else 663 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE); 664 } 665 break; 666 case AUDIT_DEVMAJOR: 667 if (name) { 668 if (audit_comparator(MAJOR(name->dev), f->op, f->val) || 669 audit_comparator(MAJOR(name->rdev), f->op, f->val)) 670 ++result; 671 } else if (ctx) { 672 list_for_each_entry(n, &ctx->names_list, list) { 673 if (audit_comparator(MAJOR(n->dev), f->op, f->val) || 674 audit_comparator(MAJOR(n->rdev), f->op, f->val)) { 675 ++result; 676 break; 677 } 678 } 679 } 680 break; 681 case AUDIT_DEVMINOR: 682 if (name) { 683 if (audit_comparator(MINOR(name->dev), f->op, f->val) || 684 audit_comparator(MINOR(name->rdev), f->op, f->val)) 685 ++result; 686 } else if (ctx) { 687 list_for_each_entry(n, &ctx->names_list, list) { 688 if (audit_comparator(MINOR(n->dev), f->op, f->val) || 689 audit_comparator(MINOR(n->rdev), f->op, f->val)) { 690 ++result; 691 break; 692 } 693 } 694 } 695 break; 696 case AUDIT_INODE: 697 if (name) 698 result = (name->ino == f->val); 699 else if (ctx) { 700 list_for_each_entry(n, &ctx->names_list, list) { 701 if (audit_comparator(n->ino, f->op, f->val)) { 702 ++result; 703 break; 704 } 705 } 706 } 707 break; 708 case AUDIT_OBJ_UID: 709 if (name) { 710 result = audit_uid_comparator(name->uid, f->op, f->uid); 711 } else if (ctx) { 712 list_for_each_entry(n, &ctx->names_list, list) { 713 if (audit_uid_comparator(n->uid, f->op, f->uid)) { 714 ++result; 715 break; 716 } 717 } 718 } 719 break; 720 case AUDIT_OBJ_GID: 721 if (name) { 722 result = audit_gid_comparator(name->gid, f->op, f->gid); 723 } else if (ctx) { 724 list_for_each_entry(n, &ctx->names_list, list) { 725 if (audit_gid_comparator(n->gid, f->op, f->gid)) { 726 ++result; 727 break; 728 } 729 } 730 } 731 break; 732 case AUDIT_WATCH: 733 if (name) 734 result = audit_watch_compare(rule->watch, name->ino, name->dev); 735 break; 736 case AUDIT_DIR: 737 if (ctx) 738 result = match_tree_refs(ctx, rule->tree); 739 break; 740 case AUDIT_LOGINUID: 741 result = 0; 742 if (ctx) 743 result = audit_uid_comparator(tsk->loginuid, f->op, f->uid); 744 break; 745 case AUDIT_SUBJ_USER: 746 case AUDIT_SUBJ_ROLE: 747 case AUDIT_SUBJ_TYPE: 748 case AUDIT_SUBJ_SEN: 749 case AUDIT_SUBJ_CLR: 750 /* NOTE: this may return negative values indicating 751 a temporary error. We simply treat this as a 752 match for now to avoid losing information that 753 may be wanted. An error message will also be 754 logged upon error */ 755 if (f->lsm_rule) { 756 if (need_sid) { 757 security_task_getsecid(tsk, &sid); 758 need_sid = 0; 759 } 760 result = security_audit_rule_match(sid, f->type, 761 f->op, 762 f->lsm_rule, 763 ctx); 764 } 765 break; 766 case AUDIT_OBJ_USER: 767 case AUDIT_OBJ_ROLE: 768 case AUDIT_OBJ_TYPE: 769 case AUDIT_OBJ_LEV_LOW: 770 case AUDIT_OBJ_LEV_HIGH: 771 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR 772 also applies here */ 773 if (f->lsm_rule) { 774 /* Find files that match */ 775 if (name) { 776 result = security_audit_rule_match( 777 name->osid, f->type, f->op, 778 f->lsm_rule, ctx); 779 } else if (ctx) { 780 list_for_each_entry(n, &ctx->names_list, list) { 781 if (security_audit_rule_match(n->osid, f->type, 782 f->op, f->lsm_rule, 783 ctx)) { 784 ++result; 785 break; 786 } 787 } 788 } 789 /* Find ipc objects that match */ 790 if (!ctx || ctx->type != AUDIT_IPC) 791 break; 792 if (security_audit_rule_match(ctx->ipc.osid, 793 f->type, f->op, 794 f->lsm_rule, ctx)) 795 ++result; 796 } 797 break; 798 case AUDIT_ARG0: 799 case AUDIT_ARG1: 800 case AUDIT_ARG2: 801 case AUDIT_ARG3: 802 if (ctx) 803 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val); 804 break; 805 case AUDIT_FILTERKEY: 806 /* ignore this field for filtering */ 807 result = 1; 808 break; 809 case AUDIT_PERM: 810 result = audit_match_perm(ctx, f->val); 811 break; 812 case AUDIT_FILETYPE: 813 result = audit_match_filetype(ctx, f->val); 814 break; 815 case AUDIT_FIELD_COMPARE: 816 result = audit_field_compare(tsk, cred, f, ctx, name); 817 break; 818 } 819 if (!result) 820 return 0; 821 } 822 823 if (ctx) { 824 if (rule->prio <= ctx->prio) 825 return 0; 826 if (rule->filterkey) { 827 kfree(ctx->filterkey); 828 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC); 829 } 830 ctx->prio = rule->prio; 831 } 832 switch (rule->action) { 833 case AUDIT_NEVER: *state = AUDIT_DISABLED; break; 834 case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; 835 } 836 return 1; 837 } 838 839 /* At process creation time, we can determine if system-call auditing is 840 * completely disabled for this task. Since we only have the task 841 * structure at this point, we can only check uid and gid. 842 */ 843 static enum audit_state audit_filter_task(struct task_struct *tsk, char **key) 844 { 845 struct audit_entry *e; 846 enum audit_state state; 847 848 rcu_read_lock(); 849 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { 850 if (audit_filter_rules(tsk, &e->rule, NULL, NULL, 851 &state, true)) { 852 if (state == AUDIT_RECORD_CONTEXT) 853 *key = kstrdup(e->rule.filterkey, GFP_ATOMIC); 854 rcu_read_unlock(); 855 return state; 856 } 857 } 858 rcu_read_unlock(); 859 return AUDIT_BUILD_CONTEXT; 860 } 861 862 /* At syscall entry and exit time, this filter is called if the 863 * audit_state is not low enough that auditing cannot take place, but is 864 * also not high enough that we already know we have to write an audit 865 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). 866 */ 867 static enum audit_state audit_filter_syscall(struct task_struct *tsk, 868 struct audit_context *ctx, 869 struct list_head *list) 870 { 871 struct audit_entry *e; 872 enum audit_state state; 873 874 if (audit_pid && tsk->tgid == audit_pid) 875 return AUDIT_DISABLED; 876 877 rcu_read_lock(); 878 if (!list_empty(list)) { 879 int word = AUDIT_WORD(ctx->major); 880 int bit = AUDIT_BIT(ctx->major); 881 882 list_for_each_entry_rcu(e, list, list) { 883 if ((e->rule.mask[word] & bit) == bit && 884 audit_filter_rules(tsk, &e->rule, ctx, NULL, 885 &state, false)) { 886 rcu_read_unlock(); 887 ctx->current_state = state; 888 return state; 889 } 890 } 891 } 892 rcu_read_unlock(); 893 return AUDIT_BUILD_CONTEXT; 894 } 895 896 /* 897 * Given an audit_name check the inode hash table to see if they match. 898 * Called holding the rcu read lock to protect the use of audit_inode_hash 899 */ 900 static int audit_filter_inode_name(struct task_struct *tsk, 901 struct audit_names *n, 902 struct audit_context *ctx) { 903 int word, bit; 904 int h = audit_hash_ino((u32)n->ino); 905 struct list_head *list = &audit_inode_hash[h]; 906 struct audit_entry *e; 907 enum audit_state state; 908 909 word = AUDIT_WORD(ctx->major); 910 bit = AUDIT_BIT(ctx->major); 911 912 if (list_empty(list)) 913 return 0; 914 915 list_for_each_entry_rcu(e, list, list) { 916 if ((e->rule.mask[word] & bit) == bit && 917 audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) { 918 ctx->current_state = state; 919 return 1; 920 } 921 } 922 923 return 0; 924 } 925 926 /* At syscall exit time, this filter is called if any audit_names have been 927 * collected during syscall processing. We only check rules in sublists at hash 928 * buckets applicable to the inode numbers in audit_names. 929 * Regarding audit_state, same rules apply as for audit_filter_syscall(). 930 */ 931 void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx) 932 { 933 struct audit_names *n; 934 935 if (audit_pid && tsk->tgid == audit_pid) 936 return; 937 938 rcu_read_lock(); 939 940 list_for_each_entry(n, &ctx->names_list, list) { 941 if (audit_filter_inode_name(tsk, n, ctx)) 942 break; 943 } 944 rcu_read_unlock(); 945 } 946 947 static inline struct audit_context *audit_get_context(struct task_struct *tsk, 948 int return_valid, 949 long return_code) 950 { 951 struct audit_context *context = tsk->audit_context; 952 953 if (!context) 954 return NULL; 955 context->return_valid = return_valid; 956 957 /* 958 * we need to fix up the return code in the audit logs if the actual 959 * return codes are later going to be fixed up by the arch specific 960 * signal handlers 961 * 962 * This is actually a test for: 963 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) || 964 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK) 965 * 966 * but is faster than a bunch of || 967 */ 968 if (unlikely(return_code <= -ERESTARTSYS) && 969 (return_code >= -ERESTART_RESTARTBLOCK) && 970 (return_code != -ENOIOCTLCMD)) 971 context->return_code = -EINTR; 972 else 973 context->return_code = return_code; 974 975 if (context->in_syscall && !context->dummy) { 976 audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]); 977 audit_filter_inodes(tsk, context); 978 } 979 980 tsk->audit_context = NULL; 981 return context; 982 } 983 984 static inline void audit_free_names(struct audit_context *context) 985 { 986 struct audit_names *n, *next; 987 988 #if AUDIT_DEBUG == 2 989 if (context->put_count + context->ino_count != context->name_count) { 990 printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d" 991 " name_count=%d put_count=%d" 992 " ino_count=%d [NOT freeing]\n", 993 __FILE__, __LINE__, 994 context->serial, context->major, context->in_syscall, 995 context->name_count, context->put_count, 996 context->ino_count); 997 list_for_each_entry(n, &context->names_list, list) { 998 printk(KERN_ERR "names[%d] = %p = %s\n", i, 999 n->name, n->name->name ?: "(null)"); 1000 } 1001 dump_stack(); 1002 return; 1003 } 1004 #endif 1005 #if AUDIT_DEBUG 1006 context->put_count = 0; 1007 context->ino_count = 0; 1008 #endif 1009 1010 list_for_each_entry_safe(n, next, &context->names_list, list) { 1011 list_del(&n->list); 1012 if (n->name && n->name_put) 1013 __putname(n->name); 1014 if (n->should_free) 1015 kfree(n); 1016 } 1017 context->name_count = 0; 1018 path_put(&context->pwd); 1019 context->pwd.dentry = NULL; 1020 context->pwd.mnt = NULL; 1021 } 1022 1023 static inline void audit_free_aux(struct audit_context *context) 1024 { 1025 struct audit_aux_data *aux; 1026 1027 while ((aux = context->aux)) { 1028 context->aux = aux->next; 1029 kfree(aux); 1030 } 1031 while ((aux = context->aux_pids)) { 1032 context->aux_pids = aux->next; 1033 kfree(aux); 1034 } 1035 } 1036 1037 static inline void audit_zero_context(struct audit_context *context, 1038 enum audit_state state) 1039 { 1040 memset(context, 0, sizeof(*context)); 1041 context->state = state; 1042 context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 1043 } 1044 1045 static inline struct audit_context *audit_alloc_context(enum audit_state state) 1046 { 1047 struct audit_context *context; 1048 1049 if (!(context = kmalloc(sizeof(*context), GFP_KERNEL))) 1050 return NULL; 1051 audit_zero_context(context, state); 1052 INIT_LIST_HEAD(&context->killed_trees); 1053 INIT_LIST_HEAD(&context->names_list); 1054 return context; 1055 } 1056 1057 /** 1058 * audit_alloc - allocate an audit context block for a task 1059 * @tsk: task 1060 * 1061 * Filter on the task information and allocate a per-task audit context 1062 * if necessary. Doing so turns on system call auditing for the 1063 * specified task. This is called from copy_process, so no lock is 1064 * needed. 1065 */ 1066 int audit_alloc(struct task_struct *tsk) 1067 { 1068 struct audit_context *context; 1069 enum audit_state state; 1070 char *key = NULL; 1071 1072 if (likely(!audit_ever_enabled)) 1073 return 0; /* Return if not auditing. */ 1074 1075 state = audit_filter_task(tsk, &key); 1076 if (state == AUDIT_DISABLED) 1077 return 0; 1078 1079 if (!(context = audit_alloc_context(state))) { 1080 kfree(key); 1081 audit_log_lost("out of memory in audit_alloc"); 1082 return -ENOMEM; 1083 } 1084 context->filterkey = key; 1085 1086 tsk->audit_context = context; 1087 set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); 1088 return 0; 1089 } 1090 1091 static inline void audit_free_context(struct audit_context *context) 1092 { 1093 audit_free_names(context); 1094 unroll_tree_refs(context, NULL, 0); 1095 free_tree_refs(context); 1096 audit_free_aux(context); 1097 kfree(context->filterkey); 1098 kfree(context->sockaddr); 1099 kfree(context); 1100 } 1101 1102 void audit_log_task_context(struct audit_buffer *ab) 1103 { 1104 char *ctx = NULL; 1105 unsigned len; 1106 int error; 1107 u32 sid; 1108 1109 security_task_getsecid(current, &sid); 1110 if (!sid) 1111 return; 1112 1113 error = security_secid_to_secctx(sid, &ctx, &len); 1114 if (error) { 1115 if (error != -EINVAL) 1116 goto error_path; 1117 return; 1118 } 1119 1120 audit_log_format(ab, " subj=%s", ctx); 1121 security_release_secctx(ctx, len); 1122 return; 1123 1124 error_path: 1125 audit_panic("error in audit_log_task_context"); 1126 return; 1127 } 1128 1129 EXPORT_SYMBOL(audit_log_task_context); 1130 1131 void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk) 1132 { 1133 const struct cred *cred; 1134 char name[sizeof(tsk->comm)]; 1135 struct mm_struct *mm = tsk->mm; 1136 char *tty; 1137 1138 if (!ab) 1139 return; 1140 1141 /* tsk == current */ 1142 cred = current_cred(); 1143 1144 spin_lock_irq(&tsk->sighand->siglock); 1145 if (tsk->signal && tsk->signal->tty) 1146 tty = tsk->signal->tty->name; 1147 else 1148 tty = "(none)"; 1149 spin_unlock_irq(&tsk->sighand->siglock); 1150 1151 1152 audit_log_format(ab, 1153 " ppid=%ld pid=%d auid=%u uid=%u gid=%u" 1154 " euid=%u suid=%u fsuid=%u" 1155 " egid=%u sgid=%u fsgid=%u ses=%u tty=%s", 1156 sys_getppid(), 1157 tsk->pid, 1158 from_kuid(&init_user_ns, tsk->loginuid), 1159 from_kuid(&init_user_ns, cred->uid), 1160 from_kgid(&init_user_ns, cred->gid), 1161 from_kuid(&init_user_ns, cred->euid), 1162 from_kuid(&init_user_ns, cred->suid), 1163 from_kuid(&init_user_ns, cred->fsuid), 1164 from_kgid(&init_user_ns, cred->egid), 1165 from_kgid(&init_user_ns, cred->sgid), 1166 from_kgid(&init_user_ns, cred->fsgid), 1167 tsk->sessionid, tty); 1168 1169 get_task_comm(name, tsk); 1170 audit_log_format(ab, " comm="); 1171 audit_log_untrustedstring(ab, name); 1172 1173 if (mm) { 1174 down_read(&mm->mmap_sem); 1175 if (mm->exe_file) 1176 audit_log_d_path(ab, " exe=", &mm->exe_file->f_path); 1177 up_read(&mm->mmap_sem); 1178 } 1179 audit_log_task_context(ab); 1180 } 1181 1182 EXPORT_SYMBOL(audit_log_task_info); 1183 1184 static int audit_log_pid_context(struct audit_context *context, pid_t pid, 1185 kuid_t auid, kuid_t uid, unsigned int sessionid, 1186 u32 sid, char *comm) 1187 { 1188 struct audit_buffer *ab; 1189 char *ctx = NULL; 1190 u32 len; 1191 int rc = 0; 1192 1193 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); 1194 if (!ab) 1195 return rc; 1196 1197 audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, 1198 from_kuid(&init_user_ns, auid), 1199 from_kuid(&init_user_ns, uid), sessionid); 1200 if (security_secid_to_secctx(sid, &ctx, &len)) { 1201 audit_log_format(ab, " obj=(none)"); 1202 rc = 1; 1203 } else { 1204 audit_log_format(ab, " obj=%s", ctx); 1205 security_release_secctx(ctx, len); 1206 } 1207 audit_log_format(ab, " ocomm="); 1208 audit_log_untrustedstring(ab, comm); 1209 audit_log_end(ab); 1210 1211 return rc; 1212 } 1213 1214 /* 1215 * to_send and len_sent accounting are very loose estimates. We aren't 1216 * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being 1217 * within about 500 bytes (next page boundary) 1218 * 1219 * why snprintf? an int is up to 12 digits long. if we just assumed when 1220 * logging that a[%d]= was going to be 16 characters long we would be wasting 1221 * space in every audit message. In one 7500 byte message we can log up to 1222 * about 1000 min size arguments. That comes down to about 50% waste of space 1223 * if we didn't do the snprintf to find out how long arg_num_len was. 1224 */ 1225 static int audit_log_single_execve_arg(struct audit_context *context, 1226 struct audit_buffer **ab, 1227 int arg_num, 1228 size_t *len_sent, 1229 const char __user *p, 1230 char *buf) 1231 { 1232 char arg_num_len_buf[12]; 1233 const char __user *tmp_p = p; 1234 /* how many digits are in arg_num? 5 is the length of ' a=""' */ 1235 size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 5; 1236 size_t len, len_left, to_send; 1237 size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN; 1238 unsigned int i, has_cntl = 0, too_long = 0; 1239 int ret; 1240 1241 /* strnlen_user includes the null we don't want to send */ 1242 len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1; 1243 1244 /* 1245 * We just created this mm, if we can't find the strings 1246 * we just copied into it something is _very_ wrong. Similar 1247 * for strings that are too long, we should not have created 1248 * any. 1249 */ 1250 if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) { 1251 WARN_ON(1); 1252 send_sig(SIGKILL, current, 0); 1253 return -1; 1254 } 1255 1256 /* walk the whole argument looking for non-ascii chars */ 1257 do { 1258 if (len_left > MAX_EXECVE_AUDIT_LEN) 1259 to_send = MAX_EXECVE_AUDIT_LEN; 1260 else 1261 to_send = len_left; 1262 ret = copy_from_user(buf, tmp_p, to_send); 1263 /* 1264 * There is no reason for this copy to be short. We just 1265 * copied them here, and the mm hasn't been exposed to user- 1266 * space yet. 1267 */ 1268 if (ret) { 1269 WARN_ON(1); 1270 send_sig(SIGKILL, current, 0); 1271 return -1; 1272 } 1273 buf[to_send] = '\0'; 1274 has_cntl = audit_string_contains_control(buf, to_send); 1275 if (has_cntl) { 1276 /* 1277 * hex messages get logged as 2 bytes, so we can only 1278 * send half as much in each message 1279 */ 1280 max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2; 1281 break; 1282 } 1283 len_left -= to_send; 1284 tmp_p += to_send; 1285 } while (len_left > 0); 1286 1287 len_left = len; 1288 1289 if (len > max_execve_audit_len) 1290 too_long = 1; 1291 1292 /* rewalk the argument actually logging the message */ 1293 for (i = 0; len_left > 0; i++) { 1294 int room_left; 1295 1296 if (len_left > max_execve_audit_len) 1297 to_send = max_execve_audit_len; 1298 else 1299 to_send = len_left; 1300 1301 /* do we have space left to send this argument in this ab? */ 1302 room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent; 1303 if (has_cntl) 1304 room_left -= (to_send * 2); 1305 else 1306 room_left -= to_send; 1307 if (room_left < 0) { 1308 *len_sent = 0; 1309 audit_log_end(*ab); 1310 *ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE); 1311 if (!*ab) 1312 return 0; 1313 } 1314 1315 /* 1316 * first record needs to say how long the original string was 1317 * so we can be sure nothing was lost. 1318 */ 1319 if ((i == 0) && (too_long)) 1320 audit_log_format(*ab, " a%d_len=%zu", arg_num, 1321 has_cntl ? 2*len : len); 1322 1323 /* 1324 * normally arguments are small enough to fit and we already 1325 * filled buf above when we checked for control characters 1326 * so don't bother with another copy_from_user 1327 */ 1328 if (len >= max_execve_audit_len) 1329 ret = copy_from_user(buf, p, to_send); 1330 else 1331 ret = 0; 1332 if (ret) { 1333 WARN_ON(1); 1334 send_sig(SIGKILL, current, 0); 1335 return -1; 1336 } 1337 buf[to_send] = '\0'; 1338 1339 /* actually log it */ 1340 audit_log_format(*ab, " a%d", arg_num); 1341 if (too_long) 1342 audit_log_format(*ab, "[%d]", i); 1343 audit_log_format(*ab, "="); 1344 if (has_cntl) 1345 audit_log_n_hex(*ab, buf, to_send); 1346 else 1347 audit_log_string(*ab, buf); 1348 1349 p += to_send; 1350 len_left -= to_send; 1351 *len_sent += arg_num_len; 1352 if (has_cntl) 1353 *len_sent += to_send * 2; 1354 else 1355 *len_sent += to_send; 1356 } 1357 /* include the null we didn't log */ 1358 return len + 1; 1359 } 1360 1361 static void audit_log_execve_info(struct audit_context *context, 1362 struct audit_buffer **ab, 1363 struct audit_aux_data_execve *axi) 1364 { 1365 int i, len; 1366 size_t len_sent = 0; 1367 const char __user *p; 1368 char *buf; 1369 1370 if (axi->mm != current->mm) 1371 return; /* execve failed, no additional info */ 1372 1373 p = (const char __user *)axi->mm->arg_start; 1374 1375 audit_log_format(*ab, "argc=%d", axi->argc); 1376 1377 /* 1378 * we need some kernel buffer to hold the userspace args. Just 1379 * allocate one big one rather than allocating one of the right size 1380 * for every single argument inside audit_log_single_execve_arg() 1381 * should be <8k allocation so should be pretty safe. 1382 */ 1383 buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL); 1384 if (!buf) { 1385 audit_panic("out of memory for argv string\n"); 1386 return; 1387 } 1388 1389 for (i = 0; i < axi->argc; i++) { 1390 len = audit_log_single_execve_arg(context, ab, i, 1391 &len_sent, p, buf); 1392 if (len <= 0) 1393 break; 1394 p += len; 1395 } 1396 kfree(buf); 1397 } 1398 1399 static void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap) 1400 { 1401 int i; 1402 1403 audit_log_format(ab, " %s=", prefix); 1404 CAP_FOR_EACH_U32(i) { 1405 audit_log_format(ab, "%08x", cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]); 1406 } 1407 } 1408 1409 static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) 1410 { 1411 kernel_cap_t *perm = &name->fcap.permitted; 1412 kernel_cap_t *inh = &name->fcap.inheritable; 1413 int log = 0; 1414 1415 if (!cap_isclear(*perm)) { 1416 audit_log_cap(ab, "cap_fp", perm); 1417 log = 1; 1418 } 1419 if (!cap_isclear(*inh)) { 1420 audit_log_cap(ab, "cap_fi", inh); 1421 log = 1; 1422 } 1423 1424 if (log) 1425 audit_log_format(ab, " cap_fe=%d cap_fver=%x", name->fcap.fE, name->fcap_ver); 1426 } 1427 1428 static void show_special(struct audit_context *context, int *call_panic) 1429 { 1430 struct audit_buffer *ab; 1431 int i; 1432 1433 ab = audit_log_start(context, GFP_KERNEL, context->type); 1434 if (!ab) 1435 return; 1436 1437 switch (context->type) { 1438 case AUDIT_SOCKETCALL: { 1439 int nargs = context->socketcall.nargs; 1440 audit_log_format(ab, "nargs=%d", nargs); 1441 for (i = 0; i < nargs; i++) 1442 audit_log_format(ab, " a%d=%lx", i, 1443 context->socketcall.args[i]); 1444 break; } 1445 case AUDIT_IPC: { 1446 u32 osid = context->ipc.osid; 1447 1448 audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho", 1449 from_kuid(&init_user_ns, context->ipc.uid), 1450 from_kgid(&init_user_ns, context->ipc.gid), 1451 context->ipc.mode); 1452 if (osid) { 1453 char *ctx = NULL; 1454 u32 len; 1455 if (security_secid_to_secctx(osid, &ctx, &len)) { 1456 audit_log_format(ab, " osid=%u", osid); 1457 *call_panic = 1; 1458 } else { 1459 audit_log_format(ab, " obj=%s", ctx); 1460 security_release_secctx(ctx, len); 1461 } 1462 } 1463 if (context->ipc.has_perm) { 1464 audit_log_end(ab); 1465 ab = audit_log_start(context, GFP_KERNEL, 1466 AUDIT_IPC_SET_PERM); 1467 audit_log_format(ab, 1468 "qbytes=%lx ouid=%u ogid=%u mode=%#ho", 1469 context->ipc.qbytes, 1470 context->ipc.perm_uid, 1471 context->ipc.perm_gid, 1472 context->ipc.perm_mode); 1473 if (!ab) 1474 return; 1475 } 1476 break; } 1477 case AUDIT_MQ_OPEN: { 1478 audit_log_format(ab, 1479 "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld " 1480 "mq_msgsize=%ld mq_curmsgs=%ld", 1481 context->mq_open.oflag, context->mq_open.mode, 1482 context->mq_open.attr.mq_flags, 1483 context->mq_open.attr.mq_maxmsg, 1484 context->mq_open.attr.mq_msgsize, 1485 context->mq_open.attr.mq_curmsgs); 1486 break; } 1487 case AUDIT_MQ_SENDRECV: { 1488 audit_log_format(ab, 1489 "mqdes=%d msg_len=%zd msg_prio=%u " 1490 "abs_timeout_sec=%ld abs_timeout_nsec=%ld", 1491 context->mq_sendrecv.mqdes, 1492 context->mq_sendrecv.msg_len, 1493 context->mq_sendrecv.msg_prio, 1494 context->mq_sendrecv.abs_timeout.tv_sec, 1495 context->mq_sendrecv.abs_timeout.tv_nsec); 1496 break; } 1497 case AUDIT_MQ_NOTIFY: { 1498 audit_log_format(ab, "mqdes=%d sigev_signo=%d", 1499 context->mq_notify.mqdes, 1500 context->mq_notify.sigev_signo); 1501 break; } 1502 case AUDIT_MQ_GETSETATTR: { 1503 struct mq_attr *attr = &context->mq_getsetattr.mqstat; 1504 audit_log_format(ab, 1505 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld " 1506 "mq_curmsgs=%ld ", 1507 context->mq_getsetattr.mqdes, 1508 attr->mq_flags, attr->mq_maxmsg, 1509 attr->mq_msgsize, attr->mq_curmsgs); 1510 break; } 1511 case AUDIT_CAPSET: { 1512 audit_log_format(ab, "pid=%d", context->capset.pid); 1513 audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable); 1514 audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted); 1515 audit_log_cap(ab, "cap_pe", &context->capset.cap.effective); 1516 break; } 1517 case AUDIT_MMAP: { 1518 audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd, 1519 context->mmap.flags); 1520 break; } 1521 } 1522 audit_log_end(ab); 1523 } 1524 1525 static void audit_log_name(struct audit_context *context, struct audit_names *n, 1526 int record_num, int *call_panic) 1527 { 1528 struct audit_buffer *ab; 1529 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH); 1530 if (!ab) 1531 return; /* audit_panic has been called */ 1532 1533 audit_log_format(ab, "item=%d", record_num); 1534 1535 if (n->name) { 1536 switch (n->name_len) { 1537 case AUDIT_NAME_FULL: 1538 /* log the full path */ 1539 audit_log_format(ab, " name="); 1540 audit_log_untrustedstring(ab, n->name->name); 1541 break; 1542 case 0: 1543 /* name was specified as a relative path and the 1544 * directory component is the cwd */ 1545 audit_log_d_path(ab, " name=", &context->pwd); 1546 break; 1547 default: 1548 /* log the name's directory component */ 1549 audit_log_format(ab, " name="); 1550 audit_log_n_untrustedstring(ab, n->name->name, 1551 n->name_len); 1552 } 1553 } else 1554 audit_log_format(ab, " name=(null)"); 1555 1556 if (n->ino != (unsigned long)-1) { 1557 audit_log_format(ab, " inode=%lu" 1558 " dev=%02x:%02x mode=%#ho" 1559 " ouid=%u ogid=%u rdev=%02x:%02x", 1560 n->ino, 1561 MAJOR(n->dev), 1562 MINOR(n->dev), 1563 n->mode, 1564 from_kuid(&init_user_ns, n->uid), 1565 from_kgid(&init_user_ns, n->gid), 1566 MAJOR(n->rdev), 1567 MINOR(n->rdev)); 1568 } 1569 if (n->osid != 0) { 1570 char *ctx = NULL; 1571 u32 len; 1572 if (security_secid_to_secctx( 1573 n->osid, &ctx, &len)) { 1574 audit_log_format(ab, " osid=%u", n->osid); 1575 *call_panic = 2; 1576 } else { 1577 audit_log_format(ab, " obj=%s", ctx); 1578 security_release_secctx(ctx, len); 1579 } 1580 } 1581 1582 audit_log_fcaps(ab, n); 1583 1584 audit_log_end(ab); 1585 } 1586 1587 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk) 1588 { 1589 int i, call_panic = 0; 1590 struct audit_buffer *ab; 1591 struct audit_aux_data *aux; 1592 struct audit_names *n; 1593 1594 /* tsk == current */ 1595 context->personality = tsk->personality; 1596 1597 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); 1598 if (!ab) 1599 return; /* audit_panic has been called */ 1600 audit_log_format(ab, "arch=%x syscall=%d", 1601 context->arch, context->major); 1602 if (context->personality != PER_LINUX) 1603 audit_log_format(ab, " per=%lx", context->personality); 1604 if (context->return_valid) 1605 audit_log_format(ab, " success=%s exit=%ld", 1606 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", 1607 context->return_code); 1608 1609 audit_log_format(ab, 1610 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d", 1611 context->argv[0], 1612 context->argv[1], 1613 context->argv[2], 1614 context->argv[3], 1615 context->name_count); 1616 1617 audit_log_task_info(ab, tsk); 1618 audit_log_key(ab, context->filterkey); 1619 audit_log_end(ab); 1620 1621 for (aux = context->aux; aux; aux = aux->next) { 1622 1623 ab = audit_log_start(context, GFP_KERNEL, aux->type); 1624 if (!ab) 1625 continue; /* audit_panic has been called */ 1626 1627 switch (aux->type) { 1628 1629 case AUDIT_EXECVE: { 1630 struct audit_aux_data_execve *axi = (void *)aux; 1631 audit_log_execve_info(context, &ab, axi); 1632 break; } 1633 1634 case AUDIT_BPRM_FCAPS: { 1635 struct audit_aux_data_bprm_fcaps *axs = (void *)aux; 1636 audit_log_format(ab, "fver=%x", axs->fcap_ver); 1637 audit_log_cap(ab, "fp", &axs->fcap.permitted); 1638 audit_log_cap(ab, "fi", &axs->fcap.inheritable); 1639 audit_log_format(ab, " fe=%d", axs->fcap.fE); 1640 audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted); 1641 audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable); 1642 audit_log_cap(ab, "old_pe", &axs->old_pcap.effective); 1643 audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted); 1644 audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable); 1645 audit_log_cap(ab, "new_pe", &axs->new_pcap.effective); 1646 break; } 1647 1648 } 1649 audit_log_end(ab); 1650 } 1651 1652 if (context->type) 1653 show_special(context, &call_panic); 1654 1655 if (context->fds[0] >= 0) { 1656 ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR); 1657 if (ab) { 1658 audit_log_format(ab, "fd0=%d fd1=%d", 1659 context->fds[0], context->fds[1]); 1660 audit_log_end(ab); 1661 } 1662 } 1663 1664 if (context->sockaddr_len) { 1665 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR); 1666 if (ab) { 1667 audit_log_format(ab, "saddr="); 1668 audit_log_n_hex(ab, (void *)context->sockaddr, 1669 context->sockaddr_len); 1670 audit_log_end(ab); 1671 } 1672 } 1673 1674 for (aux = context->aux_pids; aux; aux = aux->next) { 1675 struct audit_aux_data_pids *axs = (void *)aux; 1676 1677 for (i = 0; i < axs->pid_count; i++) 1678 if (audit_log_pid_context(context, axs->target_pid[i], 1679 axs->target_auid[i], 1680 axs->target_uid[i], 1681 axs->target_sessionid[i], 1682 axs->target_sid[i], 1683 axs->target_comm[i])) 1684 call_panic = 1; 1685 } 1686 1687 if (context->target_pid && 1688 audit_log_pid_context(context, context->target_pid, 1689 context->target_auid, context->target_uid, 1690 context->target_sessionid, 1691 context->target_sid, context->target_comm)) 1692 call_panic = 1; 1693 1694 if (context->pwd.dentry && context->pwd.mnt) { 1695 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); 1696 if (ab) { 1697 audit_log_d_path(ab, " cwd=", &context->pwd); 1698 audit_log_end(ab); 1699 } 1700 } 1701 1702 i = 0; 1703 list_for_each_entry(n, &context->names_list, list) 1704 audit_log_name(context, n, i++, &call_panic); 1705 1706 /* Send end of event record to help user space know we are finished */ 1707 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); 1708 if (ab) 1709 audit_log_end(ab); 1710 if (call_panic) 1711 audit_panic("error converting sid to string"); 1712 } 1713 1714 /** 1715 * audit_free - free a per-task audit context 1716 * @tsk: task whose audit context block to free 1717 * 1718 * Called from copy_process and do_exit 1719 */ 1720 void __audit_free(struct task_struct *tsk) 1721 { 1722 struct audit_context *context; 1723 1724 context = audit_get_context(tsk, 0, 0); 1725 if (!context) 1726 return; 1727 1728 /* Check for system calls that do not go through the exit 1729 * function (e.g., exit_group), then free context block. 1730 * We use GFP_ATOMIC here because we might be doing this 1731 * in the context of the idle thread */ 1732 /* that can happen only if we are called from do_exit() */ 1733 if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) 1734 audit_log_exit(context, tsk); 1735 if (!list_empty(&context->killed_trees)) 1736 audit_kill_trees(&context->killed_trees); 1737 1738 audit_free_context(context); 1739 } 1740 1741 /** 1742 * audit_syscall_entry - fill in an audit record at syscall entry 1743 * @arch: architecture type 1744 * @major: major syscall type (function) 1745 * @a1: additional syscall register 1 1746 * @a2: additional syscall register 2 1747 * @a3: additional syscall register 3 1748 * @a4: additional syscall register 4 1749 * 1750 * Fill in audit context at syscall entry. This only happens if the 1751 * audit context was created when the task was created and the state or 1752 * filters demand the audit context be built. If the state from the 1753 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, 1754 * then the record will be written at syscall exit time (otherwise, it 1755 * will only be written if another part of the kernel requests that it 1756 * be written). 1757 */ 1758 void __audit_syscall_entry(int arch, int major, 1759 unsigned long a1, unsigned long a2, 1760 unsigned long a3, unsigned long a4) 1761 { 1762 struct task_struct *tsk = current; 1763 struct audit_context *context = tsk->audit_context; 1764 enum audit_state state; 1765 1766 if (!context) 1767 return; 1768 1769 BUG_ON(context->in_syscall || context->name_count); 1770 1771 if (!audit_enabled) 1772 return; 1773 1774 context->arch = arch; 1775 context->major = major; 1776 context->argv[0] = a1; 1777 context->argv[1] = a2; 1778 context->argv[2] = a3; 1779 context->argv[3] = a4; 1780 1781 state = context->state; 1782 context->dummy = !audit_n_rules; 1783 if (!context->dummy && state == AUDIT_BUILD_CONTEXT) { 1784 context->prio = 0; 1785 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]); 1786 } 1787 if (state == AUDIT_DISABLED) 1788 return; 1789 1790 context->serial = 0; 1791 context->ctime = CURRENT_TIME; 1792 context->in_syscall = 1; 1793 context->current_state = state; 1794 context->ppid = 0; 1795 } 1796 1797 /** 1798 * audit_syscall_exit - deallocate audit context after a system call 1799 * @success: success value of the syscall 1800 * @return_code: return value of the syscall 1801 * 1802 * Tear down after system call. If the audit context has been marked as 1803 * auditable (either because of the AUDIT_RECORD_CONTEXT state from 1804 * filtering, or because some other part of the kernel wrote an audit 1805 * message), then write out the syscall information. In call cases, 1806 * free the names stored from getname(). 1807 */ 1808 void __audit_syscall_exit(int success, long return_code) 1809 { 1810 struct task_struct *tsk = current; 1811 struct audit_context *context; 1812 1813 if (success) 1814 success = AUDITSC_SUCCESS; 1815 else 1816 success = AUDITSC_FAILURE; 1817 1818 context = audit_get_context(tsk, success, return_code); 1819 if (!context) 1820 return; 1821 1822 if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) 1823 audit_log_exit(context, tsk); 1824 1825 context->in_syscall = 0; 1826 context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 1827 1828 if (!list_empty(&context->killed_trees)) 1829 audit_kill_trees(&context->killed_trees); 1830 1831 audit_free_names(context); 1832 unroll_tree_refs(context, NULL, 0); 1833 audit_free_aux(context); 1834 context->aux = NULL; 1835 context->aux_pids = NULL; 1836 context->target_pid = 0; 1837 context->target_sid = 0; 1838 context->sockaddr_len = 0; 1839 context->type = 0; 1840 context->fds[0] = -1; 1841 if (context->state != AUDIT_RECORD_CONTEXT) { 1842 kfree(context->filterkey); 1843 context->filterkey = NULL; 1844 } 1845 tsk->audit_context = context; 1846 } 1847 1848 static inline void handle_one(const struct inode *inode) 1849 { 1850 #ifdef CONFIG_AUDIT_TREE 1851 struct audit_context *context; 1852 struct audit_tree_refs *p; 1853 struct audit_chunk *chunk; 1854 int count; 1855 if (likely(hlist_empty(&inode->i_fsnotify_marks))) 1856 return; 1857 context = current->audit_context; 1858 p = context->trees; 1859 count = context->tree_count; 1860 rcu_read_lock(); 1861 chunk = audit_tree_lookup(inode); 1862 rcu_read_unlock(); 1863 if (!chunk) 1864 return; 1865 if (likely(put_tree_ref(context, chunk))) 1866 return; 1867 if (unlikely(!grow_tree_refs(context))) { 1868 printk(KERN_WARNING "out of memory, audit has lost a tree reference\n"); 1869 audit_set_auditable(context); 1870 audit_put_chunk(chunk); 1871 unroll_tree_refs(context, p, count); 1872 return; 1873 } 1874 put_tree_ref(context, chunk); 1875 #endif 1876 } 1877 1878 static void handle_path(const struct dentry *dentry) 1879 { 1880 #ifdef CONFIG_AUDIT_TREE 1881 struct audit_context *context; 1882 struct audit_tree_refs *p; 1883 const struct dentry *d, *parent; 1884 struct audit_chunk *drop; 1885 unsigned long seq; 1886 int count; 1887 1888 context = current->audit_context; 1889 p = context->trees; 1890 count = context->tree_count; 1891 retry: 1892 drop = NULL; 1893 d = dentry; 1894 rcu_read_lock(); 1895 seq = read_seqbegin(&rename_lock); 1896 for(;;) { 1897 struct inode *inode = d->d_inode; 1898 if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) { 1899 struct audit_chunk *chunk; 1900 chunk = audit_tree_lookup(inode); 1901 if (chunk) { 1902 if (unlikely(!put_tree_ref(context, chunk))) { 1903 drop = chunk; 1904 break; 1905 } 1906 } 1907 } 1908 parent = d->d_parent; 1909 if (parent == d) 1910 break; 1911 d = parent; 1912 } 1913 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */ 1914 rcu_read_unlock(); 1915 if (!drop) { 1916 /* just a race with rename */ 1917 unroll_tree_refs(context, p, count); 1918 goto retry; 1919 } 1920 audit_put_chunk(drop); 1921 if (grow_tree_refs(context)) { 1922 /* OK, got more space */ 1923 unroll_tree_refs(context, p, count); 1924 goto retry; 1925 } 1926 /* too bad */ 1927 printk(KERN_WARNING 1928 "out of memory, audit has lost a tree reference\n"); 1929 unroll_tree_refs(context, p, count); 1930 audit_set_auditable(context); 1931 return; 1932 } 1933 rcu_read_unlock(); 1934 #endif 1935 } 1936 1937 static struct audit_names *audit_alloc_name(struct audit_context *context, 1938 unsigned char type) 1939 { 1940 struct audit_names *aname; 1941 1942 if (context->name_count < AUDIT_NAMES) { 1943 aname = &context->preallocated_names[context->name_count]; 1944 memset(aname, 0, sizeof(*aname)); 1945 } else { 1946 aname = kzalloc(sizeof(*aname), GFP_NOFS); 1947 if (!aname) 1948 return NULL; 1949 aname->should_free = true; 1950 } 1951 1952 aname->ino = (unsigned long)-1; 1953 aname->type = type; 1954 list_add_tail(&aname->list, &context->names_list); 1955 1956 context->name_count++; 1957 #if AUDIT_DEBUG 1958 context->ino_count++; 1959 #endif 1960 return aname; 1961 } 1962 1963 /** 1964 * audit_reusename - fill out filename with info from existing entry 1965 * @uptr: userland ptr to pathname 1966 * 1967 * Search the audit_names list for the current audit context. If there is an 1968 * existing entry with a matching "uptr" then return the filename 1969 * associated with that audit_name. If not, return NULL. 1970 */ 1971 struct filename * 1972 __audit_reusename(const __user char *uptr) 1973 { 1974 struct audit_context *context = current->audit_context; 1975 struct audit_names *n; 1976 1977 list_for_each_entry(n, &context->names_list, list) { 1978 if (!n->name) 1979 continue; 1980 if (n->name->uptr == uptr) 1981 return n->name; 1982 } 1983 return NULL; 1984 } 1985 1986 /** 1987 * audit_getname - add a name to the list 1988 * @name: name to add 1989 * 1990 * Add a name to the list of audit names for this context. 1991 * Called from fs/namei.c:getname(). 1992 */ 1993 void __audit_getname(struct filename *name) 1994 { 1995 struct audit_context *context = current->audit_context; 1996 struct audit_names *n; 1997 1998 if (!context->in_syscall) { 1999 #if AUDIT_DEBUG == 2 2000 printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n", 2001 __FILE__, __LINE__, context->serial, name); 2002 dump_stack(); 2003 #endif 2004 return; 2005 } 2006 2007 #if AUDIT_DEBUG 2008 /* The filename _must_ have a populated ->name */ 2009 BUG_ON(!name->name); 2010 #endif 2011 2012 n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); 2013 if (!n) 2014 return; 2015 2016 n->name = name; 2017 n->name_len = AUDIT_NAME_FULL; 2018 n->name_put = true; 2019 name->aname = n; 2020 2021 if (!context->pwd.dentry) 2022 get_fs_pwd(current->fs, &context->pwd); 2023 } 2024 2025 /* audit_putname - intercept a putname request 2026 * @name: name to intercept and delay for putname 2027 * 2028 * If we have stored the name from getname in the audit context, 2029 * then we delay the putname until syscall exit. 2030 * Called from include/linux/fs.h:putname(). 2031 */ 2032 void audit_putname(struct filename *name) 2033 { 2034 struct audit_context *context = current->audit_context; 2035 2036 BUG_ON(!context); 2037 if (!context->in_syscall) { 2038 #if AUDIT_DEBUG == 2 2039 printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n", 2040 __FILE__, __LINE__, context->serial, name); 2041 if (context->name_count) { 2042 struct audit_names *n; 2043 int i; 2044 2045 list_for_each_entry(n, &context->names_list, list) 2046 printk(KERN_ERR "name[%d] = %p = %s\n", i, 2047 n->name, n->name->name ?: "(null)"); 2048 } 2049 #endif 2050 __putname(name); 2051 } 2052 #if AUDIT_DEBUG 2053 else { 2054 ++context->put_count; 2055 if (context->put_count > context->name_count) { 2056 printk(KERN_ERR "%s:%d(:%d): major=%d" 2057 " in_syscall=%d putname(%p) name_count=%d" 2058 " put_count=%d\n", 2059 __FILE__, __LINE__, 2060 context->serial, context->major, 2061 context->in_syscall, name->name, 2062 context->name_count, context->put_count); 2063 dump_stack(); 2064 } 2065 } 2066 #endif 2067 } 2068 2069 static inline int audit_copy_fcaps(struct audit_names *name, const struct dentry *dentry) 2070 { 2071 struct cpu_vfs_cap_data caps; 2072 int rc; 2073 2074 if (!dentry) 2075 return 0; 2076 2077 rc = get_vfs_caps_from_disk(dentry, &caps); 2078 if (rc) 2079 return rc; 2080 2081 name->fcap.permitted = caps.permitted; 2082 name->fcap.inheritable = caps.inheritable; 2083 name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 2084 name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; 2085 2086 return 0; 2087 } 2088 2089 2090 /* Copy inode data into an audit_names. */ 2091 static void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, 2092 const struct inode *inode) 2093 { 2094 name->ino = inode->i_ino; 2095 name->dev = inode->i_sb->s_dev; 2096 name->mode = inode->i_mode; 2097 name->uid = inode->i_uid; 2098 name->gid = inode->i_gid; 2099 name->rdev = inode->i_rdev; 2100 security_inode_getsecid(inode, &name->osid); 2101 audit_copy_fcaps(name, dentry); 2102 } 2103 2104 /** 2105 * __audit_inode - store the inode and device from a lookup 2106 * @name: name being audited 2107 * @dentry: dentry being audited 2108 * @parent: does this dentry represent the parent? 2109 */ 2110 void __audit_inode(struct filename *name, const struct dentry *dentry, 2111 unsigned int parent) 2112 { 2113 struct audit_context *context = current->audit_context; 2114 const struct inode *inode = dentry->d_inode; 2115 struct audit_names *n; 2116 2117 if (!context->in_syscall) 2118 return; 2119 2120 if (!name) 2121 goto out_alloc; 2122 2123 #if AUDIT_DEBUG 2124 /* The struct filename _must_ have a populated ->name */ 2125 BUG_ON(!name->name); 2126 #endif 2127 /* 2128 * If we have a pointer to an audit_names entry already, then we can 2129 * just use it directly if the type is correct. 2130 */ 2131 n = name->aname; 2132 if (n) { 2133 if (parent) { 2134 if (n->type == AUDIT_TYPE_PARENT || 2135 n->type == AUDIT_TYPE_UNKNOWN) 2136 goto out; 2137 } else { 2138 if (n->type != AUDIT_TYPE_PARENT) 2139 goto out; 2140 } 2141 } 2142 2143 list_for_each_entry_reverse(n, &context->names_list, list) { 2144 /* does the name pointer match? */ 2145 if (!n->name || n->name->name != name->name) 2146 continue; 2147 2148 /* match the correct record type */ 2149 if (parent) { 2150 if (n->type == AUDIT_TYPE_PARENT || 2151 n->type == AUDIT_TYPE_UNKNOWN) 2152 goto out; 2153 } else { 2154 if (n->type != AUDIT_TYPE_PARENT) 2155 goto out; 2156 } 2157 } 2158 2159 out_alloc: 2160 /* unable to find the name from a previous getname(). Allocate a new 2161 * anonymous entry. 2162 */ 2163 n = audit_alloc_name(context, AUDIT_TYPE_NORMAL); 2164 if (!n) 2165 return; 2166 out: 2167 if (parent) { 2168 n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL; 2169 n->type = AUDIT_TYPE_PARENT; 2170 } else { 2171 n->name_len = AUDIT_NAME_FULL; 2172 n->type = AUDIT_TYPE_NORMAL; 2173 } 2174 handle_path(dentry); 2175 audit_copy_inode(n, dentry, inode); 2176 } 2177 2178 /** 2179 * __audit_inode_child - collect inode info for created/removed objects 2180 * @parent: inode of dentry parent 2181 * @dentry: dentry being audited 2182 * @type: AUDIT_TYPE_* value that we're looking for 2183 * 2184 * For syscalls that create or remove filesystem objects, audit_inode 2185 * can only collect information for the filesystem object's parent. 2186 * This call updates the audit context with the child's information. 2187 * Syscalls that create a new filesystem object must be hooked after 2188 * the object is created. Syscalls that remove a filesystem object 2189 * must be hooked prior, in order to capture the target inode during 2190 * unsuccessful attempts. 2191 */ 2192 void __audit_inode_child(const struct inode *parent, 2193 const struct dentry *dentry, 2194 const unsigned char type) 2195 { 2196 struct audit_context *context = current->audit_context; 2197 const struct inode *inode = dentry->d_inode; 2198 const char *dname = dentry->d_name.name; 2199 struct audit_names *n, *found_parent = NULL, *found_child = NULL; 2200 2201 if (!context->in_syscall) 2202 return; 2203 2204 if (inode) 2205 handle_one(inode); 2206 2207 /* look for a parent entry first */ 2208 list_for_each_entry(n, &context->names_list, list) { 2209 if (!n->name || n->type != AUDIT_TYPE_PARENT) 2210 continue; 2211 2212 if (n->ino == parent->i_ino && 2213 !audit_compare_dname_path(dname, n->name->name, n->name_len)) { 2214 found_parent = n; 2215 break; 2216 } 2217 } 2218 2219 /* is there a matching child entry? */ 2220 list_for_each_entry(n, &context->names_list, list) { 2221 /* can only match entries that have a name */ 2222 if (!n->name || n->type != type) 2223 continue; 2224 2225 /* if we found a parent, make sure this one is a child of it */ 2226 if (found_parent && (n->name != found_parent->name)) 2227 continue; 2228 2229 if (!strcmp(dname, n->name->name) || 2230 !audit_compare_dname_path(dname, n->name->name, 2231 found_parent ? 2232 found_parent->name_len : 2233 AUDIT_NAME_FULL)) { 2234 found_child = n; 2235 break; 2236 } 2237 } 2238 2239 if (!found_parent) { 2240 /* create a new, "anonymous" parent record */ 2241 n = audit_alloc_name(context, AUDIT_TYPE_PARENT); 2242 if (!n) 2243 return; 2244 audit_copy_inode(n, NULL, parent); 2245 } 2246 2247 if (!found_child) { 2248 found_child = audit_alloc_name(context, type); 2249 if (!found_child) 2250 return; 2251 2252 /* Re-use the name belonging to the slot for a matching parent 2253 * directory. All names for this context are relinquished in 2254 * audit_free_names() */ 2255 if (found_parent) { 2256 found_child->name = found_parent->name; 2257 found_child->name_len = AUDIT_NAME_FULL; 2258 /* don't call __putname() */ 2259 found_child->name_put = false; 2260 } 2261 } 2262 if (inode) 2263 audit_copy_inode(found_child, dentry, inode); 2264 else 2265 found_child->ino = (unsigned long)-1; 2266 } 2267 EXPORT_SYMBOL_GPL(__audit_inode_child); 2268 2269 /** 2270 * auditsc_get_stamp - get local copies of audit_context values 2271 * @ctx: audit_context for the task 2272 * @t: timespec to store time recorded in the audit_context 2273 * @serial: serial value that is recorded in the audit_context 2274 * 2275 * Also sets the context as auditable. 2276 */ 2277 int auditsc_get_stamp(struct audit_context *ctx, 2278 struct timespec *t, unsigned int *serial) 2279 { 2280 if (!ctx->in_syscall) 2281 return 0; 2282 if (!ctx->serial) 2283 ctx->serial = audit_serial(); 2284 t->tv_sec = ctx->ctime.tv_sec; 2285 t->tv_nsec = ctx->ctime.tv_nsec; 2286 *serial = ctx->serial; 2287 if (!ctx->prio) { 2288 ctx->prio = 1; 2289 ctx->current_state = AUDIT_RECORD_CONTEXT; 2290 } 2291 return 1; 2292 } 2293 2294 /* global counter which is incremented every time something logs in */ 2295 static atomic_t session_id = ATOMIC_INIT(0); 2296 2297 /** 2298 * audit_set_loginuid - set current task's audit_context loginuid 2299 * @loginuid: loginuid value 2300 * 2301 * Returns 0. 2302 * 2303 * Called (set) from fs/proc/base.c::proc_loginuid_write(). 2304 */ 2305 int audit_set_loginuid(kuid_t loginuid) 2306 { 2307 struct task_struct *task = current; 2308 struct audit_context *context = task->audit_context; 2309 unsigned int sessionid; 2310 2311 #ifdef CONFIG_AUDIT_LOGINUID_IMMUTABLE 2312 if (uid_valid(task->loginuid)) 2313 return -EPERM; 2314 #else /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */ 2315 if (!capable(CAP_AUDIT_CONTROL)) 2316 return -EPERM; 2317 #endif /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */ 2318 2319 sessionid = atomic_inc_return(&session_id); 2320 if (context && context->in_syscall) { 2321 struct audit_buffer *ab; 2322 2323 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); 2324 if (ab) { 2325 audit_log_format(ab, "login pid=%d uid=%u " 2326 "old auid=%u new auid=%u" 2327 " old ses=%u new ses=%u", 2328 task->pid, 2329 from_kuid(&init_user_ns, task_uid(task)), 2330 from_kuid(&init_user_ns, task->loginuid), 2331 from_kuid(&init_user_ns, loginuid), 2332 task->sessionid, sessionid); 2333 audit_log_end(ab); 2334 } 2335 } 2336 task->sessionid = sessionid; 2337 task->loginuid = loginuid; 2338 return 0; 2339 } 2340 2341 /** 2342 * __audit_mq_open - record audit data for a POSIX MQ open 2343 * @oflag: open flag 2344 * @mode: mode bits 2345 * @attr: queue attributes 2346 * 2347 */ 2348 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr) 2349 { 2350 struct audit_context *context = current->audit_context; 2351 2352 if (attr) 2353 memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr)); 2354 else 2355 memset(&context->mq_open.attr, 0, sizeof(struct mq_attr)); 2356 2357 context->mq_open.oflag = oflag; 2358 context->mq_open.mode = mode; 2359 2360 context->type = AUDIT_MQ_OPEN; 2361 } 2362 2363 /** 2364 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive 2365 * @mqdes: MQ descriptor 2366 * @msg_len: Message length 2367 * @msg_prio: Message priority 2368 * @abs_timeout: Message timeout in absolute time 2369 * 2370 */ 2371 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, 2372 const struct timespec *abs_timeout) 2373 { 2374 struct audit_context *context = current->audit_context; 2375 struct timespec *p = &context->mq_sendrecv.abs_timeout; 2376 2377 if (abs_timeout) 2378 memcpy(p, abs_timeout, sizeof(struct timespec)); 2379 else 2380 memset(p, 0, sizeof(struct timespec)); 2381 2382 context->mq_sendrecv.mqdes = mqdes; 2383 context->mq_sendrecv.msg_len = msg_len; 2384 context->mq_sendrecv.msg_prio = msg_prio; 2385 2386 context->type = AUDIT_MQ_SENDRECV; 2387 } 2388 2389 /** 2390 * __audit_mq_notify - record audit data for a POSIX MQ notify 2391 * @mqdes: MQ descriptor 2392 * @notification: Notification event 2393 * 2394 */ 2395 2396 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification) 2397 { 2398 struct audit_context *context = current->audit_context; 2399 2400 if (notification) 2401 context->mq_notify.sigev_signo = notification->sigev_signo; 2402 else 2403 context->mq_notify.sigev_signo = 0; 2404 2405 context->mq_notify.mqdes = mqdes; 2406 context->type = AUDIT_MQ_NOTIFY; 2407 } 2408 2409 /** 2410 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute 2411 * @mqdes: MQ descriptor 2412 * @mqstat: MQ flags 2413 * 2414 */ 2415 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) 2416 { 2417 struct audit_context *context = current->audit_context; 2418 context->mq_getsetattr.mqdes = mqdes; 2419 context->mq_getsetattr.mqstat = *mqstat; 2420 context->type = AUDIT_MQ_GETSETATTR; 2421 } 2422 2423 /** 2424 * audit_ipc_obj - record audit data for ipc object 2425 * @ipcp: ipc permissions 2426 * 2427 */ 2428 void __audit_ipc_obj(struct kern_ipc_perm *ipcp) 2429 { 2430 struct audit_context *context = current->audit_context; 2431 context->ipc.uid = ipcp->uid; 2432 context->ipc.gid = ipcp->gid; 2433 context->ipc.mode = ipcp->mode; 2434 context->ipc.has_perm = 0; 2435 security_ipc_getsecid(ipcp, &context->ipc.osid); 2436 context->type = AUDIT_IPC; 2437 } 2438 2439 /** 2440 * audit_ipc_set_perm - record audit data for new ipc permissions 2441 * @qbytes: msgq bytes 2442 * @uid: msgq user id 2443 * @gid: msgq group id 2444 * @mode: msgq mode (permissions) 2445 * 2446 * Called only after audit_ipc_obj(). 2447 */ 2448 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode) 2449 { 2450 struct audit_context *context = current->audit_context; 2451 2452 context->ipc.qbytes = qbytes; 2453 context->ipc.perm_uid = uid; 2454 context->ipc.perm_gid = gid; 2455 context->ipc.perm_mode = mode; 2456 context->ipc.has_perm = 1; 2457 } 2458 2459 int __audit_bprm(struct linux_binprm *bprm) 2460 { 2461 struct audit_aux_data_execve *ax; 2462 struct audit_context *context = current->audit_context; 2463 2464 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2465 if (!ax) 2466 return -ENOMEM; 2467 2468 ax->argc = bprm->argc; 2469 ax->envc = bprm->envc; 2470 ax->mm = bprm->mm; 2471 ax->d.type = AUDIT_EXECVE; 2472 ax->d.next = context->aux; 2473 context->aux = (void *)ax; 2474 return 0; 2475 } 2476 2477 2478 /** 2479 * audit_socketcall - record audit data for sys_socketcall 2480 * @nargs: number of args 2481 * @args: args array 2482 * 2483 */ 2484 void __audit_socketcall(int nargs, unsigned long *args) 2485 { 2486 struct audit_context *context = current->audit_context; 2487 2488 context->type = AUDIT_SOCKETCALL; 2489 context->socketcall.nargs = nargs; 2490 memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long)); 2491 } 2492 2493 /** 2494 * __audit_fd_pair - record audit data for pipe and socketpair 2495 * @fd1: the first file descriptor 2496 * @fd2: the second file descriptor 2497 * 2498 */ 2499 void __audit_fd_pair(int fd1, int fd2) 2500 { 2501 struct audit_context *context = current->audit_context; 2502 context->fds[0] = fd1; 2503 context->fds[1] = fd2; 2504 } 2505 2506 /** 2507 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto 2508 * @len: data length in user space 2509 * @a: data address in kernel space 2510 * 2511 * Returns 0 for success or NULL context or < 0 on error. 2512 */ 2513 int __audit_sockaddr(int len, void *a) 2514 { 2515 struct audit_context *context = current->audit_context; 2516 2517 if (!context->sockaddr) { 2518 void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL); 2519 if (!p) 2520 return -ENOMEM; 2521 context->sockaddr = p; 2522 } 2523 2524 context->sockaddr_len = len; 2525 memcpy(context->sockaddr, a, len); 2526 return 0; 2527 } 2528 2529 void __audit_ptrace(struct task_struct *t) 2530 { 2531 struct audit_context *context = current->audit_context; 2532 2533 context->target_pid = t->pid; 2534 context->target_auid = audit_get_loginuid(t); 2535 context->target_uid = task_uid(t); 2536 context->target_sessionid = audit_get_sessionid(t); 2537 security_task_getsecid(t, &context->target_sid); 2538 memcpy(context->target_comm, t->comm, TASK_COMM_LEN); 2539 } 2540 2541 /** 2542 * audit_signal_info - record signal info for shutting down audit subsystem 2543 * @sig: signal value 2544 * @t: task being signaled 2545 * 2546 * If the audit subsystem is being terminated, record the task (pid) 2547 * and uid that is doing that. 2548 */ 2549 int __audit_signal_info(int sig, struct task_struct *t) 2550 { 2551 struct audit_aux_data_pids *axp; 2552 struct task_struct *tsk = current; 2553 struct audit_context *ctx = tsk->audit_context; 2554 kuid_t uid = current_uid(), t_uid = task_uid(t); 2555 2556 if (audit_pid && t->tgid == audit_pid) { 2557 if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) { 2558 audit_sig_pid = tsk->pid; 2559 if (uid_valid(tsk->loginuid)) 2560 audit_sig_uid = tsk->loginuid; 2561 else 2562 audit_sig_uid = uid; 2563 security_task_getsecid(tsk, &audit_sig_sid); 2564 } 2565 if (!audit_signals || audit_dummy_context()) 2566 return 0; 2567 } 2568 2569 /* optimize the common case by putting first signal recipient directly 2570 * in audit_context */ 2571 if (!ctx->target_pid) { 2572 ctx->target_pid = t->tgid; 2573 ctx->target_auid = audit_get_loginuid(t); 2574 ctx->target_uid = t_uid; 2575 ctx->target_sessionid = audit_get_sessionid(t); 2576 security_task_getsecid(t, &ctx->target_sid); 2577 memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); 2578 return 0; 2579 } 2580 2581 axp = (void *)ctx->aux_pids; 2582 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { 2583 axp = kzalloc(sizeof(*axp), GFP_ATOMIC); 2584 if (!axp) 2585 return -ENOMEM; 2586 2587 axp->d.type = AUDIT_OBJ_PID; 2588 axp->d.next = ctx->aux_pids; 2589 ctx->aux_pids = (void *)axp; 2590 } 2591 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); 2592 2593 axp->target_pid[axp->pid_count] = t->tgid; 2594 axp->target_auid[axp->pid_count] = audit_get_loginuid(t); 2595 axp->target_uid[axp->pid_count] = t_uid; 2596 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); 2597 security_task_getsecid(t, &axp->target_sid[axp->pid_count]); 2598 memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); 2599 axp->pid_count++; 2600 2601 return 0; 2602 } 2603 2604 /** 2605 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps 2606 * @bprm: pointer to the bprm being processed 2607 * @new: the proposed new credentials 2608 * @old: the old credentials 2609 * 2610 * Simply check if the proc already has the caps given by the file and if not 2611 * store the priv escalation info for later auditing at the end of the syscall 2612 * 2613 * -Eric 2614 */ 2615 int __audit_log_bprm_fcaps(struct linux_binprm *bprm, 2616 const struct cred *new, const struct cred *old) 2617 { 2618 struct audit_aux_data_bprm_fcaps *ax; 2619 struct audit_context *context = current->audit_context; 2620 struct cpu_vfs_cap_data vcaps; 2621 struct dentry *dentry; 2622 2623 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2624 if (!ax) 2625 return -ENOMEM; 2626 2627 ax->d.type = AUDIT_BPRM_FCAPS; 2628 ax->d.next = context->aux; 2629 context->aux = (void *)ax; 2630 2631 dentry = dget(bprm->file->f_dentry); 2632 get_vfs_caps_from_disk(dentry, &vcaps); 2633 dput(dentry); 2634 2635 ax->fcap.permitted = vcaps.permitted; 2636 ax->fcap.inheritable = vcaps.inheritable; 2637 ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 2638 ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; 2639 2640 ax->old_pcap.permitted = old->cap_permitted; 2641 ax->old_pcap.inheritable = old->cap_inheritable; 2642 ax->old_pcap.effective = old->cap_effective; 2643 2644 ax->new_pcap.permitted = new->cap_permitted; 2645 ax->new_pcap.inheritable = new->cap_inheritable; 2646 ax->new_pcap.effective = new->cap_effective; 2647 return 0; 2648 } 2649 2650 /** 2651 * __audit_log_capset - store information about the arguments to the capset syscall 2652 * @pid: target pid of the capset call 2653 * @new: the new credentials 2654 * @old: the old (current) credentials 2655 * 2656 * Record the aguments userspace sent to sys_capset for later printing by the 2657 * audit system if applicable 2658 */ 2659 void __audit_log_capset(pid_t pid, 2660 const struct cred *new, const struct cred *old) 2661 { 2662 struct audit_context *context = current->audit_context; 2663 context->capset.pid = pid; 2664 context->capset.cap.effective = new->cap_effective; 2665 context->capset.cap.inheritable = new->cap_effective; 2666 context->capset.cap.permitted = new->cap_permitted; 2667 context->type = AUDIT_CAPSET; 2668 } 2669 2670 void __audit_mmap_fd(int fd, int flags) 2671 { 2672 struct audit_context *context = current->audit_context; 2673 context->mmap.fd = fd; 2674 context->mmap.flags = flags; 2675 context->type = AUDIT_MMAP; 2676 } 2677 2678 static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr) 2679 { 2680 kuid_t auid, uid; 2681 kgid_t gid; 2682 unsigned int sessionid; 2683 2684 auid = audit_get_loginuid(current); 2685 sessionid = audit_get_sessionid(current); 2686 current_uid_gid(&uid, &gid); 2687 2688 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", 2689 from_kuid(&init_user_ns, auid), 2690 from_kuid(&init_user_ns, uid), 2691 from_kgid(&init_user_ns, gid), 2692 sessionid); 2693 audit_log_task_context(ab); 2694 audit_log_format(ab, " pid=%d comm=", current->pid); 2695 audit_log_untrustedstring(ab, current->comm); 2696 audit_log_format(ab, " reason="); 2697 audit_log_string(ab, reason); 2698 audit_log_format(ab, " sig=%ld", signr); 2699 } 2700 /** 2701 * audit_core_dumps - record information about processes that end abnormally 2702 * @signr: signal value 2703 * 2704 * If a process ends with a core dump, something fishy is going on and we 2705 * should record the event for investigation. 2706 */ 2707 void audit_core_dumps(long signr) 2708 { 2709 struct audit_buffer *ab; 2710 2711 if (!audit_enabled) 2712 return; 2713 2714 if (signr == SIGQUIT) /* don't care for those */ 2715 return; 2716 2717 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); 2718 audit_log_abend(ab, "memory violation", signr); 2719 audit_log_end(ab); 2720 } 2721 2722 void __audit_seccomp(unsigned long syscall, long signr, int code) 2723 { 2724 struct audit_buffer *ab; 2725 2726 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); 2727 audit_log_abend(ab, "seccomp", signr); 2728 audit_log_format(ab, " syscall=%ld", syscall); 2729 audit_log_format(ab, " compat=%d", is_compat_task()); 2730 audit_log_format(ab, " ip=0x%lx", KSTK_EIP(current)); 2731 audit_log_format(ab, " code=0x%x", code); 2732 audit_log_end(ab); 2733 } 2734 2735 struct list_head *audit_killed_trees(void) 2736 { 2737 struct audit_context *ctx = current->audit_context; 2738 if (likely(!ctx || !ctx->in_syscall)) 2739 return NULL; 2740 return &ctx->killed_trees; 2741 } 2742