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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 46 47 #include <linux/init.h> 48 #include <asm/types.h> 49 #include <linux/atomic.h> 50 #include <linux/fs.h> 51 #include <linux/namei.h> 52 #include <linux/mm.h> 53 #include <linux/export.h> 54 #include <linux/slab.h> 55 #include <linux/mount.h> 56 #include <linux/socket.h> 57 #include <linux/mqueue.h> 58 #include <linux/audit.h> 59 #include <linux/personality.h> 60 #include <linux/time.h> 61 #include <linux/netlink.h> 62 #include <linux/compiler.h> 63 #include <asm/unistd.h> 64 #include <linux/security.h> 65 #include <linux/list.h> 66 #include <linux/binfmts.h> 67 #include <linux/highmem.h> 68 #include <linux/syscalls.h> 69 #include <asm/syscall.h> 70 #include <linux/capability.h> 71 #include <linux/fs_struct.h> 72 #include <linux/compat.h> 73 #include <linux/ctype.h> 74 #include <linux/string.h> 75 #include <linux/uaccess.h> 76 #include <linux/fsnotify_backend.h> 77 #include <uapi/linux/limits.h> 78 79 #include "audit.h" 80 81 /* flags stating the success for a syscall */ 82 #define AUDITSC_INVALID 0 83 #define AUDITSC_SUCCESS 1 84 #define AUDITSC_FAILURE 2 85 86 /* no execve audit message should be longer than this (userspace limits), 87 * see the note near the top of audit_log_execve_info() about this value */ 88 #define MAX_EXECVE_AUDIT_LEN 7500 89 90 /* max length to print of cmdline/proctitle value during audit */ 91 #define MAX_PROCTITLE_AUDIT_LEN 128 92 93 /* number of audit rules */ 94 int audit_n_rules; 95 96 /* determines whether we collect data for signals sent */ 97 int audit_signals; 98 99 struct audit_aux_data { 100 struct audit_aux_data *next; 101 int type; 102 }; 103 104 #define AUDIT_AUX_IPCPERM 0 105 106 /* Number of target pids per aux struct. */ 107 #define AUDIT_AUX_PIDS 16 108 109 struct audit_aux_data_pids { 110 struct audit_aux_data d; 111 pid_t target_pid[AUDIT_AUX_PIDS]; 112 kuid_t target_auid[AUDIT_AUX_PIDS]; 113 kuid_t target_uid[AUDIT_AUX_PIDS]; 114 unsigned int target_sessionid[AUDIT_AUX_PIDS]; 115 u32 target_sid[AUDIT_AUX_PIDS]; 116 char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN]; 117 int pid_count; 118 }; 119 120 struct audit_aux_data_bprm_fcaps { 121 struct audit_aux_data d; 122 struct audit_cap_data fcap; 123 unsigned int fcap_ver; 124 struct audit_cap_data old_pcap; 125 struct audit_cap_data new_pcap; 126 }; 127 128 struct audit_tree_refs { 129 struct audit_tree_refs *next; 130 struct audit_chunk *c[31]; 131 }; 132 133 static int audit_match_perm(struct audit_context *ctx, int mask) 134 { 135 unsigned n; 136 if (unlikely(!ctx)) 137 return 0; 138 n = ctx->major; 139 140 switch (audit_classify_syscall(ctx->arch, n)) { 141 case 0: /* native */ 142 if ((mask & AUDIT_PERM_WRITE) && 143 audit_match_class(AUDIT_CLASS_WRITE, n)) 144 return 1; 145 if ((mask & AUDIT_PERM_READ) && 146 audit_match_class(AUDIT_CLASS_READ, n)) 147 return 1; 148 if ((mask & AUDIT_PERM_ATTR) && 149 audit_match_class(AUDIT_CLASS_CHATTR, n)) 150 return 1; 151 return 0; 152 case 1: /* 32bit on biarch */ 153 if ((mask & AUDIT_PERM_WRITE) && 154 audit_match_class(AUDIT_CLASS_WRITE_32, n)) 155 return 1; 156 if ((mask & AUDIT_PERM_READ) && 157 audit_match_class(AUDIT_CLASS_READ_32, n)) 158 return 1; 159 if ((mask & AUDIT_PERM_ATTR) && 160 audit_match_class(AUDIT_CLASS_CHATTR_32, n)) 161 return 1; 162 return 0; 163 case 2: /* open */ 164 return mask & ACC_MODE(ctx->argv[1]); 165 case 3: /* openat */ 166 return mask & ACC_MODE(ctx->argv[2]); 167 case 4: /* socketcall */ 168 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); 169 case 5: /* execve */ 170 return mask & AUDIT_PERM_EXEC; 171 default: 172 return 0; 173 } 174 } 175 176 static int audit_match_filetype(struct audit_context *ctx, int val) 177 { 178 struct audit_names *n; 179 umode_t mode = (umode_t)val; 180 181 if (unlikely(!ctx)) 182 return 0; 183 184 list_for_each_entry(n, &ctx->names_list, list) { 185 if ((n->ino != AUDIT_INO_UNSET) && 186 ((n->mode & S_IFMT) == mode)) 187 return 1; 188 } 189 190 return 0; 191 } 192 193 /* 194 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *; 195 * ->first_trees points to its beginning, ->trees - to the current end of data. 196 * ->tree_count is the number of free entries in array pointed to by ->trees. 197 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL, 198 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously, 199 * it's going to remain 1-element for almost any setup) until we free context itself. 200 * References in it _are_ dropped - at the same time we free/drop aux stuff. 201 */ 202 203 static void audit_set_auditable(struct audit_context *ctx) 204 { 205 if (!ctx->prio) { 206 ctx->prio = 1; 207 ctx->current_state = AUDIT_RECORD_CONTEXT; 208 } 209 } 210 211 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk) 212 { 213 struct audit_tree_refs *p = ctx->trees; 214 int left = ctx->tree_count; 215 if (likely(left)) { 216 p->c[--left] = chunk; 217 ctx->tree_count = left; 218 return 1; 219 } 220 if (!p) 221 return 0; 222 p = p->next; 223 if (p) { 224 p->c[30] = chunk; 225 ctx->trees = p; 226 ctx->tree_count = 30; 227 return 1; 228 } 229 return 0; 230 } 231 232 static int grow_tree_refs(struct audit_context *ctx) 233 { 234 struct audit_tree_refs *p = ctx->trees; 235 ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL); 236 if (!ctx->trees) { 237 ctx->trees = p; 238 return 0; 239 } 240 if (p) 241 p->next = ctx->trees; 242 else 243 ctx->first_trees = ctx->trees; 244 ctx->tree_count = 31; 245 return 1; 246 } 247 248 static void unroll_tree_refs(struct audit_context *ctx, 249 struct audit_tree_refs *p, int count) 250 { 251 struct audit_tree_refs *q; 252 int n; 253 if (!p) { 254 /* we started with empty chain */ 255 p = ctx->first_trees; 256 count = 31; 257 /* if the very first allocation has failed, nothing to do */ 258 if (!p) 259 return; 260 } 261 n = count; 262 for (q = p; q != ctx->trees; q = q->next, n = 31) { 263 while (n--) { 264 audit_put_chunk(q->c[n]); 265 q->c[n] = NULL; 266 } 267 } 268 while (n-- > ctx->tree_count) { 269 audit_put_chunk(q->c[n]); 270 q->c[n] = NULL; 271 } 272 ctx->trees = p; 273 ctx->tree_count = count; 274 } 275 276 static void free_tree_refs(struct audit_context *ctx) 277 { 278 struct audit_tree_refs *p, *q; 279 for (p = ctx->first_trees; p; p = q) { 280 q = p->next; 281 kfree(p); 282 } 283 } 284 285 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree) 286 { 287 struct audit_tree_refs *p; 288 int n; 289 if (!tree) 290 return 0; 291 /* full ones */ 292 for (p = ctx->first_trees; p != ctx->trees; p = p->next) { 293 for (n = 0; n < 31; n++) 294 if (audit_tree_match(p->c[n], tree)) 295 return 1; 296 } 297 /* partial */ 298 if (p) { 299 for (n = ctx->tree_count; n < 31; n++) 300 if (audit_tree_match(p->c[n], tree)) 301 return 1; 302 } 303 return 0; 304 } 305 306 static int audit_compare_uid(kuid_t uid, 307 struct audit_names *name, 308 struct audit_field *f, 309 struct audit_context *ctx) 310 { 311 struct audit_names *n; 312 int rc; 313 314 if (name) { 315 rc = audit_uid_comparator(uid, f->op, name->uid); 316 if (rc) 317 return rc; 318 } 319 320 if (ctx) { 321 list_for_each_entry(n, &ctx->names_list, list) { 322 rc = audit_uid_comparator(uid, f->op, n->uid); 323 if (rc) 324 return rc; 325 } 326 } 327 return 0; 328 } 329 330 static int audit_compare_gid(kgid_t gid, 331 struct audit_names *name, 332 struct audit_field *f, 333 struct audit_context *ctx) 334 { 335 struct audit_names *n; 336 int rc; 337 338 if (name) { 339 rc = audit_gid_comparator(gid, f->op, name->gid); 340 if (rc) 341 return rc; 342 } 343 344 if (ctx) { 345 list_for_each_entry(n, &ctx->names_list, list) { 346 rc = audit_gid_comparator(gid, f->op, n->gid); 347 if (rc) 348 return rc; 349 } 350 } 351 return 0; 352 } 353 354 static int audit_field_compare(struct task_struct *tsk, 355 const struct cred *cred, 356 struct audit_field *f, 357 struct audit_context *ctx, 358 struct audit_names *name) 359 { 360 switch (f->val) { 361 /* process to file object comparisons */ 362 case AUDIT_COMPARE_UID_TO_OBJ_UID: 363 return audit_compare_uid(cred->uid, name, f, ctx); 364 case AUDIT_COMPARE_GID_TO_OBJ_GID: 365 return audit_compare_gid(cred->gid, name, f, ctx); 366 case AUDIT_COMPARE_EUID_TO_OBJ_UID: 367 return audit_compare_uid(cred->euid, name, f, ctx); 368 case AUDIT_COMPARE_EGID_TO_OBJ_GID: 369 return audit_compare_gid(cred->egid, name, f, ctx); 370 case AUDIT_COMPARE_AUID_TO_OBJ_UID: 371 return audit_compare_uid(audit_get_loginuid(tsk), name, f, ctx); 372 case AUDIT_COMPARE_SUID_TO_OBJ_UID: 373 return audit_compare_uid(cred->suid, name, f, ctx); 374 case AUDIT_COMPARE_SGID_TO_OBJ_GID: 375 return audit_compare_gid(cred->sgid, name, f, ctx); 376 case AUDIT_COMPARE_FSUID_TO_OBJ_UID: 377 return audit_compare_uid(cred->fsuid, name, f, ctx); 378 case AUDIT_COMPARE_FSGID_TO_OBJ_GID: 379 return audit_compare_gid(cred->fsgid, name, f, ctx); 380 /* uid comparisons */ 381 case AUDIT_COMPARE_UID_TO_AUID: 382 return audit_uid_comparator(cred->uid, f->op, 383 audit_get_loginuid(tsk)); 384 case AUDIT_COMPARE_UID_TO_EUID: 385 return audit_uid_comparator(cred->uid, f->op, cred->euid); 386 case AUDIT_COMPARE_UID_TO_SUID: 387 return audit_uid_comparator(cred->uid, f->op, cred->suid); 388 case AUDIT_COMPARE_UID_TO_FSUID: 389 return audit_uid_comparator(cred->uid, f->op, cred->fsuid); 390 /* auid comparisons */ 391 case AUDIT_COMPARE_AUID_TO_EUID: 392 return audit_uid_comparator(audit_get_loginuid(tsk), f->op, 393 cred->euid); 394 case AUDIT_COMPARE_AUID_TO_SUID: 395 return audit_uid_comparator(audit_get_loginuid(tsk), f->op, 396 cred->suid); 397 case AUDIT_COMPARE_AUID_TO_FSUID: 398 return audit_uid_comparator(audit_get_loginuid(tsk), f->op, 399 cred->fsuid); 400 /* euid comparisons */ 401 case AUDIT_COMPARE_EUID_TO_SUID: 402 return audit_uid_comparator(cred->euid, f->op, cred->suid); 403 case AUDIT_COMPARE_EUID_TO_FSUID: 404 return audit_uid_comparator(cred->euid, f->op, cred->fsuid); 405 /* suid comparisons */ 406 case AUDIT_COMPARE_SUID_TO_FSUID: 407 return audit_uid_comparator(cred->suid, f->op, cred->fsuid); 408 /* gid comparisons */ 409 case AUDIT_COMPARE_GID_TO_EGID: 410 return audit_gid_comparator(cred->gid, f->op, cred->egid); 411 case AUDIT_COMPARE_GID_TO_SGID: 412 return audit_gid_comparator(cred->gid, f->op, cred->sgid); 413 case AUDIT_COMPARE_GID_TO_FSGID: 414 return audit_gid_comparator(cred->gid, f->op, cred->fsgid); 415 /* egid comparisons */ 416 case AUDIT_COMPARE_EGID_TO_SGID: 417 return audit_gid_comparator(cred->egid, f->op, cred->sgid); 418 case AUDIT_COMPARE_EGID_TO_FSGID: 419 return audit_gid_comparator(cred->egid, f->op, cred->fsgid); 420 /* sgid comparison */ 421 case AUDIT_COMPARE_SGID_TO_FSGID: 422 return audit_gid_comparator(cred->sgid, f->op, cred->fsgid); 423 default: 424 WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n"); 425 return 0; 426 } 427 return 0; 428 } 429 430 /* Determine if any context name data matches a rule's watch data */ 431 /* Compare a task_struct with an audit_rule. Return 1 on match, 0 432 * otherwise. 433 * 434 * If task_creation is true, this is an explicit indication that we are 435 * filtering a task rule at task creation time. This and tsk == current are 436 * the only situations where tsk->cred may be accessed without an rcu read lock. 437 */ 438 static int audit_filter_rules(struct task_struct *tsk, 439 struct audit_krule *rule, 440 struct audit_context *ctx, 441 struct audit_names *name, 442 enum audit_state *state, 443 bool task_creation) 444 { 445 const struct cred *cred; 446 int i, need_sid = 1; 447 u32 sid; 448 unsigned int sessionid; 449 450 cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation); 451 452 for (i = 0; i < rule->field_count; i++) { 453 struct audit_field *f = &rule->fields[i]; 454 struct audit_names *n; 455 int result = 0; 456 pid_t pid; 457 458 switch (f->type) { 459 case AUDIT_PID: 460 pid = task_tgid_nr(tsk); 461 result = audit_comparator(pid, f->op, f->val); 462 break; 463 case AUDIT_PPID: 464 if (ctx) { 465 if (!ctx->ppid) 466 ctx->ppid = task_ppid_nr(tsk); 467 result = audit_comparator(ctx->ppid, f->op, f->val); 468 } 469 break; 470 case AUDIT_EXE: 471 result = audit_exe_compare(tsk, rule->exe); 472 if (f->op == Audit_not_equal) 473 result = !result; 474 break; 475 case AUDIT_UID: 476 result = audit_uid_comparator(cred->uid, f->op, f->uid); 477 break; 478 case AUDIT_EUID: 479 result = audit_uid_comparator(cred->euid, f->op, f->uid); 480 break; 481 case AUDIT_SUID: 482 result = audit_uid_comparator(cred->suid, f->op, f->uid); 483 break; 484 case AUDIT_FSUID: 485 result = audit_uid_comparator(cred->fsuid, f->op, f->uid); 486 break; 487 case AUDIT_GID: 488 result = audit_gid_comparator(cred->gid, f->op, f->gid); 489 if (f->op == Audit_equal) { 490 if (!result) 491 result = groups_search(cred->group_info, f->gid); 492 } else if (f->op == Audit_not_equal) { 493 if (result) 494 result = !groups_search(cred->group_info, f->gid); 495 } 496 break; 497 case AUDIT_EGID: 498 result = audit_gid_comparator(cred->egid, f->op, f->gid); 499 if (f->op == Audit_equal) { 500 if (!result) 501 result = groups_search(cred->group_info, f->gid); 502 } else if (f->op == Audit_not_equal) { 503 if (result) 504 result = !groups_search(cred->group_info, f->gid); 505 } 506 break; 507 case AUDIT_SGID: 508 result = audit_gid_comparator(cred->sgid, f->op, f->gid); 509 break; 510 case AUDIT_FSGID: 511 result = audit_gid_comparator(cred->fsgid, f->op, f->gid); 512 break; 513 case AUDIT_SESSIONID: 514 sessionid = audit_get_sessionid(tsk); 515 result = audit_comparator(sessionid, f->op, f->val); 516 break; 517 case AUDIT_PERS: 518 result = audit_comparator(tsk->personality, f->op, f->val); 519 break; 520 case AUDIT_ARCH: 521 if (ctx) 522 result = audit_comparator(ctx->arch, f->op, f->val); 523 break; 524 525 case AUDIT_EXIT: 526 if (ctx && ctx->return_valid) 527 result = audit_comparator(ctx->return_code, f->op, f->val); 528 break; 529 case AUDIT_SUCCESS: 530 if (ctx && ctx->return_valid) { 531 if (f->val) 532 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS); 533 else 534 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE); 535 } 536 break; 537 case AUDIT_DEVMAJOR: 538 if (name) { 539 if (audit_comparator(MAJOR(name->dev), f->op, f->val) || 540 audit_comparator(MAJOR(name->rdev), f->op, f->val)) 541 ++result; 542 } else if (ctx) { 543 list_for_each_entry(n, &ctx->names_list, list) { 544 if (audit_comparator(MAJOR(n->dev), f->op, f->val) || 545 audit_comparator(MAJOR(n->rdev), f->op, f->val)) { 546 ++result; 547 break; 548 } 549 } 550 } 551 break; 552 case AUDIT_DEVMINOR: 553 if (name) { 554 if (audit_comparator(MINOR(name->dev), f->op, f->val) || 555 audit_comparator(MINOR(name->rdev), f->op, f->val)) 556 ++result; 557 } else if (ctx) { 558 list_for_each_entry(n, &ctx->names_list, list) { 559 if (audit_comparator(MINOR(n->dev), f->op, f->val) || 560 audit_comparator(MINOR(n->rdev), f->op, f->val)) { 561 ++result; 562 break; 563 } 564 } 565 } 566 break; 567 case AUDIT_INODE: 568 if (name) 569 result = audit_comparator(name->ino, f->op, f->val); 570 else if (ctx) { 571 list_for_each_entry(n, &ctx->names_list, list) { 572 if (audit_comparator(n->ino, f->op, f->val)) { 573 ++result; 574 break; 575 } 576 } 577 } 578 break; 579 case AUDIT_OBJ_UID: 580 if (name) { 581 result = audit_uid_comparator(name->uid, f->op, f->uid); 582 } else if (ctx) { 583 list_for_each_entry(n, &ctx->names_list, list) { 584 if (audit_uid_comparator(n->uid, f->op, f->uid)) { 585 ++result; 586 break; 587 } 588 } 589 } 590 break; 591 case AUDIT_OBJ_GID: 592 if (name) { 593 result = audit_gid_comparator(name->gid, f->op, f->gid); 594 } else if (ctx) { 595 list_for_each_entry(n, &ctx->names_list, list) { 596 if (audit_gid_comparator(n->gid, f->op, f->gid)) { 597 ++result; 598 break; 599 } 600 } 601 } 602 break; 603 case AUDIT_WATCH: 604 if (name) { 605 result = audit_watch_compare(rule->watch, 606 name->ino, 607 name->dev); 608 if (f->op == Audit_not_equal) 609 result = !result; 610 } 611 break; 612 case AUDIT_DIR: 613 if (ctx) { 614 result = match_tree_refs(ctx, rule->tree); 615 if (f->op == Audit_not_equal) 616 result = !result; 617 } 618 break; 619 case AUDIT_LOGINUID: 620 result = audit_uid_comparator(audit_get_loginuid(tsk), 621 f->op, f->uid); 622 break; 623 case AUDIT_LOGINUID_SET: 624 result = audit_comparator(audit_loginuid_set(tsk), f->op, f->val); 625 break; 626 case AUDIT_SADDR_FAM: 627 if (ctx->sockaddr) 628 result = audit_comparator(ctx->sockaddr->ss_family, 629 f->op, f->val); 630 break; 631 case AUDIT_SUBJ_USER: 632 case AUDIT_SUBJ_ROLE: 633 case AUDIT_SUBJ_TYPE: 634 case AUDIT_SUBJ_SEN: 635 case AUDIT_SUBJ_CLR: 636 /* NOTE: this may return negative values indicating 637 a temporary error. We simply treat this as a 638 match for now to avoid losing information that 639 may be wanted. An error message will also be 640 logged upon error */ 641 if (f->lsm_rule) { 642 if (need_sid) { 643 security_task_getsecid(tsk, &sid); 644 need_sid = 0; 645 } 646 result = security_audit_rule_match(sid, f->type, 647 f->op, 648 f->lsm_rule); 649 } 650 break; 651 case AUDIT_OBJ_USER: 652 case AUDIT_OBJ_ROLE: 653 case AUDIT_OBJ_TYPE: 654 case AUDIT_OBJ_LEV_LOW: 655 case AUDIT_OBJ_LEV_HIGH: 656 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR 657 also applies here */ 658 if (f->lsm_rule) { 659 /* Find files that match */ 660 if (name) { 661 result = security_audit_rule_match( 662 name->osid, 663 f->type, 664 f->op, 665 f->lsm_rule); 666 } else if (ctx) { 667 list_for_each_entry(n, &ctx->names_list, list) { 668 if (security_audit_rule_match( 669 n->osid, 670 f->type, 671 f->op, 672 f->lsm_rule)) { 673 ++result; 674 break; 675 } 676 } 677 } 678 /* Find ipc objects that match */ 679 if (!ctx || ctx->type != AUDIT_IPC) 680 break; 681 if (security_audit_rule_match(ctx->ipc.osid, 682 f->type, f->op, 683 f->lsm_rule)) 684 ++result; 685 } 686 break; 687 case AUDIT_ARG0: 688 case AUDIT_ARG1: 689 case AUDIT_ARG2: 690 case AUDIT_ARG3: 691 if (ctx) 692 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val); 693 break; 694 case AUDIT_FILTERKEY: 695 /* ignore this field for filtering */ 696 result = 1; 697 break; 698 case AUDIT_PERM: 699 result = audit_match_perm(ctx, f->val); 700 if (f->op == Audit_not_equal) 701 result = !result; 702 break; 703 case AUDIT_FILETYPE: 704 result = audit_match_filetype(ctx, f->val); 705 if (f->op == Audit_not_equal) 706 result = !result; 707 break; 708 case AUDIT_FIELD_COMPARE: 709 result = audit_field_compare(tsk, cred, f, ctx, name); 710 break; 711 } 712 if (!result) 713 return 0; 714 } 715 716 if (ctx) { 717 if (rule->prio <= ctx->prio) 718 return 0; 719 if (rule->filterkey) { 720 kfree(ctx->filterkey); 721 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC); 722 } 723 ctx->prio = rule->prio; 724 } 725 switch (rule->action) { 726 case AUDIT_NEVER: 727 *state = AUDIT_DISABLED; 728 break; 729 case AUDIT_ALWAYS: 730 *state = AUDIT_RECORD_CONTEXT; 731 break; 732 } 733 return 1; 734 } 735 736 /* At process creation time, we can determine if system-call auditing is 737 * completely disabled for this task. Since we only have the task 738 * structure at this point, we can only check uid and gid. 739 */ 740 static enum audit_state audit_filter_task(struct task_struct *tsk, char **key) 741 { 742 struct audit_entry *e; 743 enum audit_state state; 744 745 rcu_read_lock(); 746 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { 747 if (audit_filter_rules(tsk, &e->rule, NULL, NULL, 748 &state, true)) { 749 if (state == AUDIT_RECORD_CONTEXT) 750 *key = kstrdup(e->rule.filterkey, GFP_ATOMIC); 751 rcu_read_unlock(); 752 return state; 753 } 754 } 755 rcu_read_unlock(); 756 return AUDIT_BUILD_CONTEXT; 757 } 758 759 static int audit_in_mask(const struct audit_krule *rule, unsigned long val) 760 { 761 int word, bit; 762 763 if (val > 0xffffffff) 764 return false; 765 766 word = AUDIT_WORD(val); 767 if (word >= AUDIT_BITMASK_SIZE) 768 return false; 769 770 bit = AUDIT_BIT(val); 771 772 return rule->mask[word] & bit; 773 } 774 775 /* At syscall entry and exit time, this filter is called if the 776 * audit_state is not low enough that auditing cannot take place, but is 777 * also not high enough that we already know we have to write an audit 778 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). 779 */ 780 static enum audit_state audit_filter_syscall(struct task_struct *tsk, 781 struct audit_context *ctx, 782 struct list_head *list) 783 { 784 struct audit_entry *e; 785 enum audit_state state; 786 787 if (auditd_test_task(tsk)) 788 return AUDIT_DISABLED; 789 790 rcu_read_lock(); 791 list_for_each_entry_rcu(e, list, list) { 792 if (audit_in_mask(&e->rule, ctx->major) && 793 audit_filter_rules(tsk, &e->rule, ctx, NULL, 794 &state, false)) { 795 rcu_read_unlock(); 796 ctx->current_state = state; 797 return state; 798 } 799 } 800 rcu_read_unlock(); 801 return AUDIT_BUILD_CONTEXT; 802 } 803 804 /* 805 * Given an audit_name check the inode hash table to see if they match. 806 * Called holding the rcu read lock to protect the use of audit_inode_hash 807 */ 808 static int audit_filter_inode_name(struct task_struct *tsk, 809 struct audit_names *n, 810 struct audit_context *ctx) { 811 int h = audit_hash_ino((u32)n->ino); 812 struct list_head *list = &audit_inode_hash[h]; 813 struct audit_entry *e; 814 enum audit_state state; 815 816 list_for_each_entry_rcu(e, list, list) { 817 if (audit_in_mask(&e->rule, ctx->major) && 818 audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) { 819 ctx->current_state = state; 820 return 1; 821 } 822 } 823 return 0; 824 } 825 826 /* At syscall exit time, this filter is called if any audit_names have been 827 * collected during syscall processing. We only check rules in sublists at hash 828 * buckets applicable to the inode numbers in audit_names. 829 * Regarding audit_state, same rules apply as for audit_filter_syscall(). 830 */ 831 void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx) 832 { 833 struct audit_names *n; 834 835 if (auditd_test_task(tsk)) 836 return; 837 838 rcu_read_lock(); 839 840 list_for_each_entry(n, &ctx->names_list, list) { 841 if (audit_filter_inode_name(tsk, n, ctx)) 842 break; 843 } 844 rcu_read_unlock(); 845 } 846 847 static inline void audit_proctitle_free(struct audit_context *context) 848 { 849 kfree(context->proctitle.value); 850 context->proctitle.value = NULL; 851 context->proctitle.len = 0; 852 } 853 854 static inline void audit_free_module(struct audit_context *context) 855 { 856 if (context->type == AUDIT_KERN_MODULE) { 857 kfree(context->module.name); 858 context->module.name = NULL; 859 } 860 } 861 static inline void audit_free_names(struct audit_context *context) 862 { 863 struct audit_names *n, *next; 864 865 list_for_each_entry_safe(n, next, &context->names_list, list) { 866 list_del(&n->list); 867 if (n->name) 868 putname(n->name); 869 if (n->should_free) 870 kfree(n); 871 } 872 context->name_count = 0; 873 path_put(&context->pwd); 874 context->pwd.dentry = NULL; 875 context->pwd.mnt = NULL; 876 } 877 878 static inline void audit_free_aux(struct audit_context *context) 879 { 880 struct audit_aux_data *aux; 881 882 while ((aux = context->aux)) { 883 context->aux = aux->next; 884 kfree(aux); 885 } 886 while ((aux = context->aux_pids)) { 887 context->aux_pids = aux->next; 888 kfree(aux); 889 } 890 } 891 892 static inline struct audit_context *audit_alloc_context(enum audit_state state) 893 { 894 struct audit_context *context; 895 896 context = kzalloc(sizeof(*context), GFP_KERNEL); 897 if (!context) 898 return NULL; 899 context->state = state; 900 context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 901 INIT_LIST_HEAD(&context->killed_trees); 902 INIT_LIST_HEAD(&context->names_list); 903 return context; 904 } 905 906 /** 907 * audit_alloc - allocate an audit context block for a task 908 * @tsk: task 909 * 910 * Filter on the task information and allocate a per-task audit context 911 * if necessary. Doing so turns on system call auditing for the 912 * specified task. This is called from copy_process, so no lock is 913 * needed. 914 */ 915 int audit_alloc(struct task_struct *tsk) 916 { 917 struct audit_context *context; 918 enum audit_state state; 919 char *key = NULL; 920 921 if (likely(!audit_ever_enabled)) 922 return 0; /* Return if not auditing. */ 923 924 state = audit_filter_task(tsk, &key); 925 if (state == AUDIT_DISABLED) { 926 clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); 927 return 0; 928 } 929 930 if (!(context = audit_alloc_context(state))) { 931 kfree(key); 932 audit_log_lost("out of memory in audit_alloc"); 933 return -ENOMEM; 934 } 935 context->filterkey = key; 936 937 audit_set_context(tsk, context); 938 set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); 939 return 0; 940 } 941 942 static inline void audit_free_context(struct audit_context *context) 943 { 944 audit_free_module(context); 945 audit_free_names(context); 946 unroll_tree_refs(context, NULL, 0); 947 free_tree_refs(context); 948 audit_free_aux(context); 949 kfree(context->filterkey); 950 kfree(context->sockaddr); 951 audit_proctitle_free(context); 952 kfree(context); 953 } 954 955 static int audit_log_pid_context(struct audit_context *context, pid_t pid, 956 kuid_t auid, kuid_t uid, unsigned int sessionid, 957 u32 sid, char *comm) 958 { 959 struct audit_buffer *ab; 960 char *ctx = NULL; 961 u32 len; 962 int rc = 0; 963 964 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); 965 if (!ab) 966 return rc; 967 968 audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, 969 from_kuid(&init_user_ns, auid), 970 from_kuid(&init_user_ns, uid), sessionid); 971 if (sid) { 972 if (security_secid_to_secctx(sid, &ctx, &len)) { 973 audit_log_format(ab, " obj=(none)"); 974 rc = 1; 975 } else { 976 audit_log_format(ab, " obj=%s", ctx); 977 security_release_secctx(ctx, len); 978 } 979 } 980 audit_log_format(ab, " ocomm="); 981 audit_log_untrustedstring(ab, comm); 982 audit_log_end(ab); 983 984 return rc; 985 } 986 987 static void audit_log_execve_info(struct audit_context *context, 988 struct audit_buffer **ab) 989 { 990 long len_max; 991 long len_rem; 992 long len_full; 993 long len_buf; 994 long len_abuf = 0; 995 long len_tmp; 996 bool require_data; 997 bool encode; 998 unsigned int iter; 999 unsigned int arg; 1000 char *buf_head; 1001 char *buf; 1002 const char __user *p = (const char __user *)current->mm->arg_start; 1003 1004 /* NOTE: this buffer needs to be large enough to hold all the non-arg 1005 * data we put in the audit record for this argument (see the 1006 * code below) ... at this point in time 96 is plenty */ 1007 char abuf[96]; 1008 1009 /* NOTE: we set MAX_EXECVE_AUDIT_LEN to a rather arbitrary limit, the 1010 * current value of 7500 is not as important as the fact that it 1011 * is less than 8k, a setting of 7500 gives us plenty of wiggle 1012 * room if we go over a little bit in the logging below */ 1013 WARN_ON_ONCE(MAX_EXECVE_AUDIT_LEN > 7500); 1014 len_max = MAX_EXECVE_AUDIT_LEN; 1015 1016 /* scratch buffer to hold the userspace args */ 1017 buf_head = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL); 1018 if (!buf_head) { 1019 audit_panic("out of memory for argv string"); 1020 return; 1021 } 1022 buf = buf_head; 1023 1024 audit_log_format(*ab, "argc=%d", context->execve.argc); 1025 1026 len_rem = len_max; 1027 len_buf = 0; 1028 len_full = 0; 1029 require_data = true; 1030 encode = false; 1031 iter = 0; 1032 arg = 0; 1033 do { 1034 /* NOTE: we don't ever want to trust this value for anything 1035 * serious, but the audit record format insists we 1036 * provide an argument length for really long arguments, 1037 * e.g. > MAX_EXECVE_AUDIT_LEN, so we have no choice but 1038 * to use strncpy_from_user() to obtain this value for 1039 * recording in the log, although we don't use it 1040 * anywhere here to avoid a double-fetch problem */ 1041 if (len_full == 0) 1042 len_full = strnlen_user(p, MAX_ARG_STRLEN) - 1; 1043 1044 /* read more data from userspace */ 1045 if (require_data) { 1046 /* can we make more room in the buffer? */ 1047 if (buf != buf_head) { 1048 memmove(buf_head, buf, len_buf); 1049 buf = buf_head; 1050 } 1051 1052 /* fetch as much as we can of the argument */ 1053 len_tmp = strncpy_from_user(&buf_head[len_buf], p, 1054 len_max - len_buf); 1055 if (len_tmp == -EFAULT) { 1056 /* unable to copy from userspace */ 1057 send_sig(SIGKILL, current, 0); 1058 goto out; 1059 } else if (len_tmp == (len_max - len_buf)) { 1060 /* buffer is not large enough */ 1061 require_data = true; 1062 /* NOTE: if we are going to span multiple 1063 * buffers force the encoding so we stand 1064 * a chance at a sane len_full value and 1065 * consistent record encoding */ 1066 encode = true; 1067 len_full = len_full * 2; 1068 p += len_tmp; 1069 } else { 1070 require_data = false; 1071 if (!encode) 1072 encode = audit_string_contains_control( 1073 buf, len_tmp); 1074 /* try to use a trusted value for len_full */ 1075 if (len_full < len_max) 1076 len_full = (encode ? 1077 len_tmp * 2 : len_tmp); 1078 p += len_tmp + 1; 1079 } 1080 len_buf += len_tmp; 1081 buf_head[len_buf] = '\0'; 1082 1083 /* length of the buffer in the audit record? */ 1084 len_abuf = (encode ? len_buf * 2 : len_buf + 2); 1085 } 1086 1087 /* write as much as we can to the audit log */ 1088 if (len_buf >= 0) { 1089 /* NOTE: some magic numbers here - basically if we 1090 * can't fit a reasonable amount of data into the 1091 * existing audit buffer, flush it and start with 1092 * a new buffer */ 1093 if ((sizeof(abuf) + 8) > len_rem) { 1094 len_rem = len_max; 1095 audit_log_end(*ab); 1096 *ab = audit_log_start(context, 1097 GFP_KERNEL, AUDIT_EXECVE); 1098 if (!*ab) 1099 goto out; 1100 } 1101 1102 /* create the non-arg portion of the arg record */ 1103 len_tmp = 0; 1104 if (require_data || (iter > 0) || 1105 ((len_abuf + sizeof(abuf)) > len_rem)) { 1106 if (iter == 0) { 1107 len_tmp += snprintf(&abuf[len_tmp], 1108 sizeof(abuf) - len_tmp, 1109 " a%d_len=%lu", 1110 arg, len_full); 1111 } 1112 len_tmp += snprintf(&abuf[len_tmp], 1113 sizeof(abuf) - len_tmp, 1114 " a%d[%d]=", arg, iter++); 1115 } else 1116 len_tmp += snprintf(&abuf[len_tmp], 1117 sizeof(abuf) - len_tmp, 1118 " a%d=", arg); 1119 WARN_ON(len_tmp >= sizeof(abuf)); 1120 abuf[sizeof(abuf) - 1] = '\0'; 1121 1122 /* log the arg in the audit record */ 1123 audit_log_format(*ab, "%s", abuf); 1124 len_rem -= len_tmp; 1125 len_tmp = len_buf; 1126 if (encode) { 1127 if (len_abuf > len_rem) 1128 len_tmp = len_rem / 2; /* encoding */ 1129 audit_log_n_hex(*ab, buf, len_tmp); 1130 len_rem -= len_tmp * 2; 1131 len_abuf -= len_tmp * 2; 1132 } else { 1133 if (len_abuf > len_rem) 1134 len_tmp = len_rem - 2; /* quotes */ 1135 audit_log_n_string(*ab, buf, len_tmp); 1136 len_rem -= len_tmp + 2; 1137 /* don't subtract the "2" because we still need 1138 * to add quotes to the remaining string */ 1139 len_abuf -= len_tmp; 1140 } 1141 len_buf -= len_tmp; 1142 buf += len_tmp; 1143 } 1144 1145 /* ready to move to the next argument? */ 1146 if ((len_buf == 0) && !require_data) { 1147 arg++; 1148 iter = 0; 1149 len_full = 0; 1150 require_data = true; 1151 encode = false; 1152 } 1153 } while (arg < context->execve.argc); 1154 1155 /* NOTE: the caller handles the final audit_log_end() call */ 1156 1157 out: 1158 kfree(buf_head); 1159 } 1160 1161 static void audit_log_cap(struct audit_buffer *ab, char *prefix, 1162 kernel_cap_t *cap) 1163 { 1164 int i; 1165 1166 if (cap_isclear(*cap)) { 1167 audit_log_format(ab, " %s=0", prefix); 1168 return; 1169 } 1170 audit_log_format(ab, " %s=", prefix); 1171 CAP_FOR_EACH_U32(i) 1172 audit_log_format(ab, "%08x", cap->cap[CAP_LAST_U32 - i]); 1173 } 1174 1175 static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) 1176 { 1177 if (name->fcap_ver == -1) { 1178 audit_log_format(ab, " cap_fe=? cap_fver=? cap_fp=? cap_fi=?"); 1179 return; 1180 } 1181 audit_log_cap(ab, "cap_fp", &name->fcap.permitted); 1182 audit_log_cap(ab, "cap_fi", &name->fcap.inheritable); 1183 audit_log_format(ab, " cap_fe=%d cap_fver=%x cap_frootid=%d", 1184 name->fcap.fE, name->fcap_ver, 1185 from_kuid(&init_user_ns, name->fcap.rootid)); 1186 } 1187 1188 static void show_special(struct audit_context *context, int *call_panic) 1189 { 1190 struct audit_buffer *ab; 1191 int i; 1192 1193 ab = audit_log_start(context, GFP_KERNEL, context->type); 1194 if (!ab) 1195 return; 1196 1197 switch (context->type) { 1198 case AUDIT_SOCKETCALL: { 1199 int nargs = context->socketcall.nargs; 1200 audit_log_format(ab, "nargs=%d", nargs); 1201 for (i = 0; i < nargs; i++) 1202 audit_log_format(ab, " a%d=%lx", i, 1203 context->socketcall.args[i]); 1204 break; } 1205 case AUDIT_IPC: { 1206 u32 osid = context->ipc.osid; 1207 1208 audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho", 1209 from_kuid(&init_user_ns, context->ipc.uid), 1210 from_kgid(&init_user_ns, context->ipc.gid), 1211 context->ipc.mode); 1212 if (osid) { 1213 char *ctx = NULL; 1214 u32 len; 1215 if (security_secid_to_secctx(osid, &ctx, &len)) { 1216 audit_log_format(ab, " osid=%u", osid); 1217 *call_panic = 1; 1218 } else { 1219 audit_log_format(ab, " obj=%s", ctx); 1220 security_release_secctx(ctx, len); 1221 } 1222 } 1223 if (context->ipc.has_perm) { 1224 audit_log_end(ab); 1225 ab = audit_log_start(context, GFP_KERNEL, 1226 AUDIT_IPC_SET_PERM); 1227 if (unlikely(!ab)) 1228 return; 1229 audit_log_format(ab, 1230 "qbytes=%lx ouid=%u ogid=%u mode=%#ho", 1231 context->ipc.qbytes, 1232 context->ipc.perm_uid, 1233 context->ipc.perm_gid, 1234 context->ipc.perm_mode); 1235 } 1236 break; } 1237 case AUDIT_MQ_OPEN: 1238 audit_log_format(ab, 1239 "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld " 1240 "mq_msgsize=%ld mq_curmsgs=%ld", 1241 context->mq_open.oflag, context->mq_open.mode, 1242 context->mq_open.attr.mq_flags, 1243 context->mq_open.attr.mq_maxmsg, 1244 context->mq_open.attr.mq_msgsize, 1245 context->mq_open.attr.mq_curmsgs); 1246 break; 1247 case AUDIT_MQ_SENDRECV: 1248 audit_log_format(ab, 1249 "mqdes=%d msg_len=%zd msg_prio=%u " 1250 "abs_timeout_sec=%lld abs_timeout_nsec=%ld", 1251 context->mq_sendrecv.mqdes, 1252 context->mq_sendrecv.msg_len, 1253 context->mq_sendrecv.msg_prio, 1254 (long long) context->mq_sendrecv.abs_timeout.tv_sec, 1255 context->mq_sendrecv.abs_timeout.tv_nsec); 1256 break; 1257 case AUDIT_MQ_NOTIFY: 1258 audit_log_format(ab, "mqdes=%d sigev_signo=%d", 1259 context->mq_notify.mqdes, 1260 context->mq_notify.sigev_signo); 1261 break; 1262 case AUDIT_MQ_GETSETATTR: { 1263 struct mq_attr *attr = &context->mq_getsetattr.mqstat; 1264 audit_log_format(ab, 1265 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld " 1266 "mq_curmsgs=%ld ", 1267 context->mq_getsetattr.mqdes, 1268 attr->mq_flags, attr->mq_maxmsg, 1269 attr->mq_msgsize, attr->mq_curmsgs); 1270 break; } 1271 case AUDIT_CAPSET: 1272 audit_log_format(ab, "pid=%d", context->capset.pid); 1273 audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable); 1274 audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted); 1275 audit_log_cap(ab, "cap_pe", &context->capset.cap.effective); 1276 audit_log_cap(ab, "cap_pa", &context->capset.cap.ambient); 1277 break; 1278 case AUDIT_MMAP: 1279 audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd, 1280 context->mmap.flags); 1281 break; 1282 case AUDIT_EXECVE: 1283 audit_log_execve_info(context, &ab); 1284 break; 1285 case AUDIT_KERN_MODULE: 1286 audit_log_format(ab, "name="); 1287 if (context->module.name) { 1288 audit_log_untrustedstring(ab, context->module.name); 1289 } else 1290 audit_log_format(ab, "(null)"); 1291 1292 break; 1293 } 1294 audit_log_end(ab); 1295 } 1296 1297 static inline int audit_proctitle_rtrim(char *proctitle, int len) 1298 { 1299 char *end = proctitle + len - 1; 1300 while (end > proctitle && !isprint(*end)) 1301 end--; 1302 1303 /* catch the case where proctitle is only 1 non-print character */ 1304 len = end - proctitle + 1; 1305 len -= isprint(proctitle[len-1]) == 0; 1306 return len; 1307 } 1308 1309 /* 1310 * audit_log_name - produce AUDIT_PATH record from struct audit_names 1311 * @context: audit_context for the task 1312 * @n: audit_names structure with reportable details 1313 * @path: optional path to report instead of audit_names->name 1314 * @record_num: record number to report when handling a list of names 1315 * @call_panic: optional pointer to int that will be updated if secid fails 1316 */ 1317 static void audit_log_name(struct audit_context *context, struct audit_names *n, 1318 const struct path *path, int record_num, int *call_panic) 1319 { 1320 struct audit_buffer *ab; 1321 1322 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH); 1323 if (!ab) 1324 return; 1325 1326 audit_log_format(ab, "item=%d", record_num); 1327 1328 if (path) 1329 audit_log_d_path(ab, " name=", path); 1330 else if (n->name) { 1331 switch (n->name_len) { 1332 case AUDIT_NAME_FULL: 1333 /* log the full path */ 1334 audit_log_format(ab, " name="); 1335 audit_log_untrustedstring(ab, n->name->name); 1336 break; 1337 case 0: 1338 /* name was specified as a relative path and the 1339 * directory component is the cwd 1340 */ 1341 audit_log_d_path(ab, " name=", &context->pwd); 1342 break; 1343 default: 1344 /* log the name's directory component */ 1345 audit_log_format(ab, " name="); 1346 audit_log_n_untrustedstring(ab, n->name->name, 1347 n->name_len); 1348 } 1349 } else 1350 audit_log_format(ab, " name=(null)"); 1351 1352 if (n->ino != AUDIT_INO_UNSET) 1353 audit_log_format(ab, " inode=%lu dev=%02x:%02x mode=%#ho ouid=%u ogid=%u rdev=%02x:%02x", 1354 n->ino, 1355 MAJOR(n->dev), 1356 MINOR(n->dev), 1357 n->mode, 1358 from_kuid(&init_user_ns, n->uid), 1359 from_kgid(&init_user_ns, n->gid), 1360 MAJOR(n->rdev), 1361 MINOR(n->rdev)); 1362 if (n->osid != 0) { 1363 char *ctx = NULL; 1364 u32 len; 1365 1366 if (security_secid_to_secctx( 1367 n->osid, &ctx, &len)) { 1368 audit_log_format(ab, " osid=%u", n->osid); 1369 if (call_panic) 1370 *call_panic = 2; 1371 } else { 1372 audit_log_format(ab, " obj=%s", ctx); 1373 security_release_secctx(ctx, len); 1374 } 1375 } 1376 1377 /* log the audit_names record type */ 1378 switch (n->type) { 1379 case AUDIT_TYPE_NORMAL: 1380 audit_log_format(ab, " nametype=NORMAL"); 1381 break; 1382 case AUDIT_TYPE_PARENT: 1383 audit_log_format(ab, " nametype=PARENT"); 1384 break; 1385 case AUDIT_TYPE_CHILD_DELETE: 1386 audit_log_format(ab, " nametype=DELETE"); 1387 break; 1388 case AUDIT_TYPE_CHILD_CREATE: 1389 audit_log_format(ab, " nametype=CREATE"); 1390 break; 1391 default: 1392 audit_log_format(ab, " nametype=UNKNOWN"); 1393 break; 1394 } 1395 1396 audit_log_fcaps(ab, n); 1397 audit_log_end(ab); 1398 } 1399 1400 static void audit_log_proctitle(void) 1401 { 1402 int res; 1403 char *buf; 1404 char *msg = "(null)"; 1405 int len = strlen(msg); 1406 struct audit_context *context = audit_context(); 1407 struct audit_buffer *ab; 1408 1409 if (!context || context->dummy) 1410 return; 1411 1412 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE); 1413 if (!ab) 1414 return; /* audit_panic or being filtered */ 1415 1416 audit_log_format(ab, "proctitle="); 1417 1418 /* Not cached */ 1419 if (!context->proctitle.value) { 1420 buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL); 1421 if (!buf) 1422 goto out; 1423 /* Historically called this from procfs naming */ 1424 res = get_cmdline(current, buf, MAX_PROCTITLE_AUDIT_LEN); 1425 if (res == 0) { 1426 kfree(buf); 1427 goto out; 1428 } 1429 res = audit_proctitle_rtrim(buf, res); 1430 if (res == 0) { 1431 kfree(buf); 1432 goto out; 1433 } 1434 context->proctitle.value = buf; 1435 context->proctitle.len = res; 1436 } 1437 msg = context->proctitle.value; 1438 len = context->proctitle.len; 1439 out: 1440 audit_log_n_untrustedstring(ab, msg, len); 1441 audit_log_end(ab); 1442 } 1443 1444 static void audit_log_exit(void) 1445 { 1446 int i, call_panic = 0; 1447 struct audit_context *context = audit_context(); 1448 struct audit_buffer *ab; 1449 struct audit_aux_data *aux; 1450 struct audit_names *n; 1451 1452 context->personality = current->personality; 1453 1454 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); 1455 if (!ab) 1456 return; /* audit_panic has been called */ 1457 audit_log_format(ab, "arch=%x syscall=%d", 1458 context->arch, context->major); 1459 if (context->personality != PER_LINUX) 1460 audit_log_format(ab, " per=%lx", context->personality); 1461 if (context->return_valid) 1462 audit_log_format(ab, " success=%s exit=%ld", 1463 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", 1464 context->return_code); 1465 1466 audit_log_format(ab, 1467 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d", 1468 context->argv[0], 1469 context->argv[1], 1470 context->argv[2], 1471 context->argv[3], 1472 context->name_count); 1473 1474 audit_log_task_info(ab); 1475 audit_log_key(ab, context->filterkey); 1476 audit_log_end(ab); 1477 1478 for (aux = context->aux; aux; aux = aux->next) { 1479 1480 ab = audit_log_start(context, GFP_KERNEL, aux->type); 1481 if (!ab) 1482 continue; /* audit_panic has been called */ 1483 1484 switch (aux->type) { 1485 1486 case AUDIT_BPRM_FCAPS: { 1487 struct audit_aux_data_bprm_fcaps *axs = (void *)aux; 1488 audit_log_format(ab, "fver=%x", axs->fcap_ver); 1489 audit_log_cap(ab, "fp", &axs->fcap.permitted); 1490 audit_log_cap(ab, "fi", &axs->fcap.inheritable); 1491 audit_log_format(ab, " fe=%d", axs->fcap.fE); 1492 audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted); 1493 audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable); 1494 audit_log_cap(ab, "old_pe", &axs->old_pcap.effective); 1495 audit_log_cap(ab, "old_pa", &axs->old_pcap.ambient); 1496 audit_log_cap(ab, "pp", &axs->new_pcap.permitted); 1497 audit_log_cap(ab, "pi", &axs->new_pcap.inheritable); 1498 audit_log_cap(ab, "pe", &axs->new_pcap.effective); 1499 audit_log_cap(ab, "pa", &axs->new_pcap.ambient); 1500 audit_log_format(ab, " frootid=%d", 1501 from_kuid(&init_user_ns, 1502 axs->fcap.rootid)); 1503 break; } 1504 1505 } 1506 audit_log_end(ab); 1507 } 1508 1509 if (context->type) 1510 show_special(context, &call_panic); 1511 1512 if (context->fds[0] >= 0) { 1513 ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR); 1514 if (ab) { 1515 audit_log_format(ab, "fd0=%d fd1=%d", 1516 context->fds[0], context->fds[1]); 1517 audit_log_end(ab); 1518 } 1519 } 1520 1521 if (context->sockaddr_len) { 1522 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR); 1523 if (ab) { 1524 audit_log_format(ab, "saddr="); 1525 audit_log_n_hex(ab, (void *)context->sockaddr, 1526 context->sockaddr_len); 1527 audit_log_end(ab); 1528 } 1529 } 1530 1531 for (aux = context->aux_pids; aux; aux = aux->next) { 1532 struct audit_aux_data_pids *axs = (void *)aux; 1533 1534 for (i = 0; i < axs->pid_count; i++) 1535 if (audit_log_pid_context(context, axs->target_pid[i], 1536 axs->target_auid[i], 1537 axs->target_uid[i], 1538 axs->target_sessionid[i], 1539 axs->target_sid[i], 1540 axs->target_comm[i])) 1541 call_panic = 1; 1542 } 1543 1544 if (context->target_pid && 1545 audit_log_pid_context(context, context->target_pid, 1546 context->target_auid, context->target_uid, 1547 context->target_sessionid, 1548 context->target_sid, context->target_comm)) 1549 call_panic = 1; 1550 1551 if (context->pwd.dentry && context->pwd.mnt) { 1552 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); 1553 if (ab) { 1554 audit_log_d_path(ab, "cwd=", &context->pwd); 1555 audit_log_end(ab); 1556 } 1557 } 1558 1559 i = 0; 1560 list_for_each_entry(n, &context->names_list, list) { 1561 if (n->hidden) 1562 continue; 1563 audit_log_name(context, n, NULL, i++, &call_panic); 1564 } 1565 1566 audit_log_proctitle(); 1567 1568 /* Send end of event record to help user space know we are finished */ 1569 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); 1570 if (ab) 1571 audit_log_end(ab); 1572 if (call_panic) 1573 audit_panic("error converting sid to string"); 1574 } 1575 1576 /** 1577 * __audit_free - free a per-task audit context 1578 * @tsk: task whose audit context block to free 1579 * 1580 * Called from copy_process and do_exit 1581 */ 1582 void __audit_free(struct task_struct *tsk) 1583 { 1584 struct audit_context *context = tsk->audit_context; 1585 1586 if (!context) 1587 return; 1588 1589 if (!list_empty(&context->killed_trees)) 1590 audit_kill_trees(context); 1591 1592 /* We are called either by do_exit() or the fork() error handling code; 1593 * in the former case tsk == current and in the latter tsk is a 1594 * random task_struct that doesn't doesn't have any meaningful data we 1595 * need to log via audit_log_exit(). 1596 */ 1597 if (tsk == current && !context->dummy && context->in_syscall) { 1598 context->return_valid = 0; 1599 context->return_code = 0; 1600 1601 audit_filter_syscall(tsk, context, 1602 &audit_filter_list[AUDIT_FILTER_EXIT]); 1603 audit_filter_inodes(tsk, context); 1604 if (context->current_state == AUDIT_RECORD_CONTEXT) 1605 audit_log_exit(); 1606 } 1607 1608 audit_set_context(tsk, NULL); 1609 audit_free_context(context); 1610 } 1611 1612 /** 1613 * __audit_syscall_entry - fill in an audit record at syscall entry 1614 * @major: major syscall type (function) 1615 * @a1: additional syscall register 1 1616 * @a2: additional syscall register 2 1617 * @a3: additional syscall register 3 1618 * @a4: additional syscall register 4 1619 * 1620 * Fill in audit context at syscall entry. This only happens if the 1621 * audit context was created when the task was created and the state or 1622 * filters demand the audit context be built. If the state from the 1623 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, 1624 * then the record will be written at syscall exit time (otherwise, it 1625 * will only be written if another part of the kernel requests that it 1626 * be written). 1627 */ 1628 void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2, 1629 unsigned long a3, unsigned long a4) 1630 { 1631 struct audit_context *context = audit_context(); 1632 enum audit_state state; 1633 1634 if (!audit_enabled || !context) 1635 return; 1636 1637 BUG_ON(context->in_syscall || context->name_count); 1638 1639 state = context->state; 1640 if (state == AUDIT_DISABLED) 1641 return; 1642 1643 context->dummy = !audit_n_rules; 1644 if (!context->dummy && state == AUDIT_BUILD_CONTEXT) { 1645 context->prio = 0; 1646 if (auditd_test_task(current)) 1647 return; 1648 } 1649 1650 context->arch = syscall_get_arch(current); 1651 context->major = major; 1652 context->argv[0] = a1; 1653 context->argv[1] = a2; 1654 context->argv[2] = a3; 1655 context->argv[3] = a4; 1656 context->serial = 0; 1657 context->in_syscall = 1; 1658 context->current_state = state; 1659 context->ppid = 0; 1660 ktime_get_coarse_real_ts64(&context->ctime); 1661 } 1662 1663 /** 1664 * __audit_syscall_exit - deallocate audit context after a system call 1665 * @success: success value of the syscall 1666 * @return_code: return value of the syscall 1667 * 1668 * Tear down after system call. If the audit context has been marked as 1669 * auditable (either because of the AUDIT_RECORD_CONTEXT state from 1670 * filtering, or because some other part of the kernel wrote an audit 1671 * message), then write out the syscall information. In call cases, 1672 * free the names stored from getname(). 1673 */ 1674 void __audit_syscall_exit(int success, long return_code) 1675 { 1676 struct audit_context *context; 1677 1678 context = audit_context(); 1679 if (!context) 1680 return; 1681 1682 if (!list_empty(&context->killed_trees)) 1683 audit_kill_trees(context); 1684 1685 if (!context->dummy && context->in_syscall) { 1686 if (success) 1687 context->return_valid = AUDITSC_SUCCESS; 1688 else 1689 context->return_valid = AUDITSC_FAILURE; 1690 1691 /* 1692 * we need to fix up the return code in the audit logs if the 1693 * actual return codes are later going to be fixed up by the 1694 * arch specific signal handlers 1695 * 1696 * This is actually a test for: 1697 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) || 1698 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK) 1699 * 1700 * but is faster than a bunch of || 1701 */ 1702 if (unlikely(return_code <= -ERESTARTSYS) && 1703 (return_code >= -ERESTART_RESTARTBLOCK) && 1704 (return_code != -ENOIOCTLCMD)) 1705 context->return_code = -EINTR; 1706 else 1707 context->return_code = return_code; 1708 1709 audit_filter_syscall(current, context, 1710 &audit_filter_list[AUDIT_FILTER_EXIT]); 1711 audit_filter_inodes(current, context); 1712 if (context->current_state == AUDIT_RECORD_CONTEXT) 1713 audit_log_exit(); 1714 } 1715 1716 context->in_syscall = 0; 1717 context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 1718 1719 audit_free_module(context); 1720 audit_free_names(context); 1721 unroll_tree_refs(context, NULL, 0); 1722 audit_free_aux(context); 1723 context->aux = NULL; 1724 context->aux_pids = NULL; 1725 context->target_pid = 0; 1726 context->target_sid = 0; 1727 context->sockaddr_len = 0; 1728 context->type = 0; 1729 context->fds[0] = -1; 1730 if (context->state != AUDIT_RECORD_CONTEXT) { 1731 kfree(context->filterkey); 1732 context->filterkey = NULL; 1733 } 1734 } 1735 1736 static inline void handle_one(const struct inode *inode) 1737 { 1738 struct audit_context *context; 1739 struct audit_tree_refs *p; 1740 struct audit_chunk *chunk; 1741 int count; 1742 if (likely(!inode->i_fsnotify_marks)) 1743 return; 1744 context = audit_context(); 1745 p = context->trees; 1746 count = context->tree_count; 1747 rcu_read_lock(); 1748 chunk = audit_tree_lookup(inode); 1749 rcu_read_unlock(); 1750 if (!chunk) 1751 return; 1752 if (likely(put_tree_ref(context, chunk))) 1753 return; 1754 if (unlikely(!grow_tree_refs(context))) { 1755 pr_warn("out of memory, audit has lost a tree reference\n"); 1756 audit_set_auditable(context); 1757 audit_put_chunk(chunk); 1758 unroll_tree_refs(context, p, count); 1759 return; 1760 } 1761 put_tree_ref(context, chunk); 1762 } 1763 1764 static void handle_path(const struct dentry *dentry) 1765 { 1766 struct audit_context *context; 1767 struct audit_tree_refs *p; 1768 const struct dentry *d, *parent; 1769 struct audit_chunk *drop; 1770 unsigned long seq; 1771 int count; 1772 1773 context = audit_context(); 1774 p = context->trees; 1775 count = context->tree_count; 1776 retry: 1777 drop = NULL; 1778 d = dentry; 1779 rcu_read_lock(); 1780 seq = read_seqbegin(&rename_lock); 1781 for(;;) { 1782 struct inode *inode = d_backing_inode(d); 1783 if (inode && unlikely(inode->i_fsnotify_marks)) { 1784 struct audit_chunk *chunk; 1785 chunk = audit_tree_lookup(inode); 1786 if (chunk) { 1787 if (unlikely(!put_tree_ref(context, chunk))) { 1788 drop = chunk; 1789 break; 1790 } 1791 } 1792 } 1793 parent = d->d_parent; 1794 if (parent == d) 1795 break; 1796 d = parent; 1797 } 1798 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */ 1799 rcu_read_unlock(); 1800 if (!drop) { 1801 /* just a race with rename */ 1802 unroll_tree_refs(context, p, count); 1803 goto retry; 1804 } 1805 audit_put_chunk(drop); 1806 if (grow_tree_refs(context)) { 1807 /* OK, got more space */ 1808 unroll_tree_refs(context, p, count); 1809 goto retry; 1810 } 1811 /* too bad */ 1812 pr_warn("out of memory, audit has lost a tree reference\n"); 1813 unroll_tree_refs(context, p, count); 1814 audit_set_auditable(context); 1815 return; 1816 } 1817 rcu_read_unlock(); 1818 } 1819 1820 static struct audit_names *audit_alloc_name(struct audit_context *context, 1821 unsigned char type) 1822 { 1823 struct audit_names *aname; 1824 1825 if (context->name_count < AUDIT_NAMES) { 1826 aname = &context->preallocated_names[context->name_count]; 1827 memset(aname, 0, sizeof(*aname)); 1828 } else { 1829 aname = kzalloc(sizeof(*aname), GFP_NOFS); 1830 if (!aname) 1831 return NULL; 1832 aname->should_free = true; 1833 } 1834 1835 aname->ino = AUDIT_INO_UNSET; 1836 aname->type = type; 1837 list_add_tail(&aname->list, &context->names_list); 1838 1839 context->name_count++; 1840 return aname; 1841 } 1842 1843 /** 1844 * __audit_reusename - fill out filename with info from existing entry 1845 * @uptr: userland ptr to pathname 1846 * 1847 * Search the audit_names list for the current audit context. If there is an 1848 * existing entry with a matching "uptr" then return the filename 1849 * associated with that audit_name. If not, return NULL. 1850 */ 1851 struct filename * 1852 __audit_reusename(const __user char *uptr) 1853 { 1854 struct audit_context *context = audit_context(); 1855 struct audit_names *n; 1856 1857 list_for_each_entry(n, &context->names_list, list) { 1858 if (!n->name) 1859 continue; 1860 if (n->name->uptr == uptr) { 1861 n->name->refcnt++; 1862 return n->name; 1863 } 1864 } 1865 return NULL; 1866 } 1867 1868 /** 1869 * __audit_getname - add a name to the list 1870 * @name: name to add 1871 * 1872 * Add a name to the list of audit names for this context. 1873 * Called from fs/namei.c:getname(). 1874 */ 1875 void __audit_getname(struct filename *name) 1876 { 1877 struct audit_context *context = audit_context(); 1878 struct audit_names *n; 1879 1880 if (!context->in_syscall) 1881 return; 1882 1883 n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); 1884 if (!n) 1885 return; 1886 1887 n->name = name; 1888 n->name_len = AUDIT_NAME_FULL; 1889 name->aname = n; 1890 name->refcnt++; 1891 1892 if (!context->pwd.dentry) 1893 get_fs_pwd(current->fs, &context->pwd); 1894 } 1895 1896 static inline int audit_copy_fcaps(struct audit_names *name, 1897 const struct dentry *dentry) 1898 { 1899 struct cpu_vfs_cap_data caps; 1900 int rc; 1901 1902 if (!dentry) 1903 return 0; 1904 1905 rc = get_vfs_caps_from_disk(dentry, &caps); 1906 if (rc) 1907 return rc; 1908 1909 name->fcap.permitted = caps.permitted; 1910 name->fcap.inheritable = caps.inheritable; 1911 name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 1912 name->fcap.rootid = caps.rootid; 1913 name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> 1914 VFS_CAP_REVISION_SHIFT; 1915 1916 return 0; 1917 } 1918 1919 /* Copy inode data into an audit_names. */ 1920 static void audit_copy_inode(struct audit_names *name, 1921 const struct dentry *dentry, 1922 struct inode *inode, unsigned int flags) 1923 { 1924 name->ino = inode->i_ino; 1925 name->dev = inode->i_sb->s_dev; 1926 name->mode = inode->i_mode; 1927 name->uid = inode->i_uid; 1928 name->gid = inode->i_gid; 1929 name->rdev = inode->i_rdev; 1930 security_inode_getsecid(inode, &name->osid); 1931 if (flags & AUDIT_INODE_NOEVAL) { 1932 name->fcap_ver = -1; 1933 return; 1934 } 1935 audit_copy_fcaps(name, dentry); 1936 } 1937 1938 /** 1939 * __audit_inode - store the inode and device from a lookup 1940 * @name: name being audited 1941 * @dentry: dentry being audited 1942 * @flags: attributes for this particular entry 1943 */ 1944 void __audit_inode(struct filename *name, const struct dentry *dentry, 1945 unsigned int flags) 1946 { 1947 struct audit_context *context = audit_context(); 1948 struct inode *inode = d_backing_inode(dentry); 1949 struct audit_names *n; 1950 bool parent = flags & AUDIT_INODE_PARENT; 1951 struct audit_entry *e; 1952 struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS]; 1953 int i; 1954 1955 if (!context->in_syscall) 1956 return; 1957 1958 rcu_read_lock(); 1959 list_for_each_entry_rcu(e, list, list) { 1960 for (i = 0; i < e->rule.field_count; i++) { 1961 struct audit_field *f = &e->rule.fields[i]; 1962 1963 if (f->type == AUDIT_FSTYPE 1964 && audit_comparator(inode->i_sb->s_magic, 1965 f->op, f->val) 1966 && e->rule.action == AUDIT_NEVER) { 1967 rcu_read_unlock(); 1968 return; 1969 } 1970 } 1971 } 1972 rcu_read_unlock(); 1973 1974 if (!name) 1975 goto out_alloc; 1976 1977 /* 1978 * If we have a pointer to an audit_names entry already, then we can 1979 * just use it directly if the type is correct. 1980 */ 1981 n = name->aname; 1982 if (n) { 1983 if (parent) { 1984 if (n->type == AUDIT_TYPE_PARENT || 1985 n->type == AUDIT_TYPE_UNKNOWN) 1986 goto out; 1987 } else { 1988 if (n->type != AUDIT_TYPE_PARENT) 1989 goto out; 1990 } 1991 } 1992 1993 list_for_each_entry_reverse(n, &context->names_list, list) { 1994 if (n->ino) { 1995 /* valid inode number, use that for the comparison */ 1996 if (n->ino != inode->i_ino || 1997 n->dev != inode->i_sb->s_dev) 1998 continue; 1999 } else if (n->name) { 2000 /* inode number has not been set, check the name */ 2001 if (strcmp(n->name->name, name->name)) 2002 continue; 2003 } else 2004 /* no inode and no name (?!) ... this is odd ... */ 2005 continue; 2006 2007 /* match the correct record type */ 2008 if (parent) { 2009 if (n->type == AUDIT_TYPE_PARENT || 2010 n->type == AUDIT_TYPE_UNKNOWN) 2011 goto out; 2012 } else { 2013 if (n->type != AUDIT_TYPE_PARENT) 2014 goto out; 2015 } 2016 } 2017 2018 out_alloc: 2019 /* unable to find an entry with both a matching name and type */ 2020 n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); 2021 if (!n) 2022 return; 2023 if (name) { 2024 n->name = name; 2025 name->refcnt++; 2026 } 2027 2028 out: 2029 if (parent) { 2030 n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL; 2031 n->type = AUDIT_TYPE_PARENT; 2032 if (flags & AUDIT_INODE_HIDDEN) 2033 n->hidden = true; 2034 } else { 2035 n->name_len = AUDIT_NAME_FULL; 2036 n->type = AUDIT_TYPE_NORMAL; 2037 } 2038 handle_path(dentry); 2039 audit_copy_inode(n, dentry, inode, flags & AUDIT_INODE_NOEVAL); 2040 } 2041 2042 void __audit_file(const struct file *file) 2043 { 2044 __audit_inode(NULL, file->f_path.dentry, 0); 2045 } 2046 2047 /** 2048 * __audit_inode_child - collect inode info for created/removed objects 2049 * @parent: inode of dentry parent 2050 * @dentry: dentry being audited 2051 * @type: AUDIT_TYPE_* value that we're looking for 2052 * 2053 * For syscalls that create or remove filesystem objects, audit_inode 2054 * can only collect information for the filesystem object's parent. 2055 * This call updates the audit context with the child's information. 2056 * Syscalls that create a new filesystem object must be hooked after 2057 * the object is created. Syscalls that remove a filesystem object 2058 * must be hooked prior, in order to capture the target inode during 2059 * unsuccessful attempts. 2060 */ 2061 void __audit_inode_child(struct inode *parent, 2062 const struct dentry *dentry, 2063 const unsigned char type) 2064 { 2065 struct audit_context *context = audit_context(); 2066 struct inode *inode = d_backing_inode(dentry); 2067 const struct qstr *dname = &dentry->d_name; 2068 struct audit_names *n, *found_parent = NULL, *found_child = NULL; 2069 struct audit_entry *e; 2070 struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS]; 2071 int i; 2072 2073 if (!context->in_syscall) 2074 return; 2075 2076 rcu_read_lock(); 2077 list_for_each_entry_rcu(e, list, list) { 2078 for (i = 0; i < e->rule.field_count; i++) { 2079 struct audit_field *f = &e->rule.fields[i]; 2080 2081 if (f->type == AUDIT_FSTYPE 2082 && audit_comparator(parent->i_sb->s_magic, 2083 f->op, f->val) 2084 && e->rule.action == AUDIT_NEVER) { 2085 rcu_read_unlock(); 2086 return; 2087 } 2088 } 2089 } 2090 rcu_read_unlock(); 2091 2092 if (inode) 2093 handle_one(inode); 2094 2095 /* look for a parent entry first */ 2096 list_for_each_entry(n, &context->names_list, list) { 2097 if (!n->name || 2098 (n->type != AUDIT_TYPE_PARENT && 2099 n->type != AUDIT_TYPE_UNKNOWN)) 2100 continue; 2101 2102 if (n->ino == parent->i_ino && n->dev == parent->i_sb->s_dev && 2103 !audit_compare_dname_path(dname, 2104 n->name->name, n->name_len)) { 2105 if (n->type == AUDIT_TYPE_UNKNOWN) 2106 n->type = AUDIT_TYPE_PARENT; 2107 found_parent = n; 2108 break; 2109 } 2110 } 2111 2112 /* is there a matching child entry? */ 2113 list_for_each_entry(n, &context->names_list, list) { 2114 /* can only match entries that have a name */ 2115 if (!n->name || 2116 (n->type != type && n->type != AUDIT_TYPE_UNKNOWN)) 2117 continue; 2118 2119 if (!strcmp(dname->name, n->name->name) || 2120 !audit_compare_dname_path(dname, n->name->name, 2121 found_parent ? 2122 found_parent->name_len : 2123 AUDIT_NAME_FULL)) { 2124 if (n->type == AUDIT_TYPE_UNKNOWN) 2125 n->type = type; 2126 found_child = n; 2127 break; 2128 } 2129 } 2130 2131 if (!found_parent) { 2132 /* create a new, "anonymous" parent record */ 2133 n = audit_alloc_name(context, AUDIT_TYPE_PARENT); 2134 if (!n) 2135 return; 2136 audit_copy_inode(n, NULL, parent, 0); 2137 } 2138 2139 if (!found_child) { 2140 found_child = audit_alloc_name(context, type); 2141 if (!found_child) 2142 return; 2143 2144 /* Re-use the name belonging to the slot for a matching parent 2145 * directory. All names for this context are relinquished in 2146 * audit_free_names() */ 2147 if (found_parent) { 2148 found_child->name = found_parent->name; 2149 found_child->name_len = AUDIT_NAME_FULL; 2150 found_child->name->refcnt++; 2151 } 2152 } 2153 2154 if (inode) 2155 audit_copy_inode(found_child, dentry, inode, 0); 2156 else 2157 found_child->ino = AUDIT_INO_UNSET; 2158 } 2159 EXPORT_SYMBOL_GPL(__audit_inode_child); 2160 2161 /** 2162 * auditsc_get_stamp - get local copies of audit_context values 2163 * @ctx: audit_context for the task 2164 * @t: timespec64 to store time recorded in the audit_context 2165 * @serial: serial value that is recorded in the audit_context 2166 * 2167 * Also sets the context as auditable. 2168 */ 2169 int auditsc_get_stamp(struct audit_context *ctx, 2170 struct timespec64 *t, unsigned int *serial) 2171 { 2172 if (!ctx->in_syscall) 2173 return 0; 2174 if (!ctx->serial) 2175 ctx->serial = audit_serial(); 2176 t->tv_sec = ctx->ctime.tv_sec; 2177 t->tv_nsec = ctx->ctime.tv_nsec; 2178 *serial = ctx->serial; 2179 if (!ctx->prio) { 2180 ctx->prio = 1; 2181 ctx->current_state = AUDIT_RECORD_CONTEXT; 2182 } 2183 return 1; 2184 } 2185 2186 /** 2187 * __audit_mq_open - record audit data for a POSIX MQ open 2188 * @oflag: open flag 2189 * @mode: mode bits 2190 * @attr: queue attributes 2191 * 2192 */ 2193 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr) 2194 { 2195 struct audit_context *context = audit_context(); 2196 2197 if (attr) 2198 memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr)); 2199 else 2200 memset(&context->mq_open.attr, 0, sizeof(struct mq_attr)); 2201 2202 context->mq_open.oflag = oflag; 2203 context->mq_open.mode = mode; 2204 2205 context->type = AUDIT_MQ_OPEN; 2206 } 2207 2208 /** 2209 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive 2210 * @mqdes: MQ descriptor 2211 * @msg_len: Message length 2212 * @msg_prio: Message priority 2213 * @abs_timeout: Message timeout in absolute time 2214 * 2215 */ 2216 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, 2217 const struct timespec64 *abs_timeout) 2218 { 2219 struct audit_context *context = audit_context(); 2220 struct timespec64 *p = &context->mq_sendrecv.abs_timeout; 2221 2222 if (abs_timeout) 2223 memcpy(p, abs_timeout, sizeof(*p)); 2224 else 2225 memset(p, 0, sizeof(*p)); 2226 2227 context->mq_sendrecv.mqdes = mqdes; 2228 context->mq_sendrecv.msg_len = msg_len; 2229 context->mq_sendrecv.msg_prio = msg_prio; 2230 2231 context->type = AUDIT_MQ_SENDRECV; 2232 } 2233 2234 /** 2235 * __audit_mq_notify - record audit data for a POSIX MQ notify 2236 * @mqdes: MQ descriptor 2237 * @notification: Notification event 2238 * 2239 */ 2240 2241 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification) 2242 { 2243 struct audit_context *context = audit_context(); 2244 2245 if (notification) 2246 context->mq_notify.sigev_signo = notification->sigev_signo; 2247 else 2248 context->mq_notify.sigev_signo = 0; 2249 2250 context->mq_notify.mqdes = mqdes; 2251 context->type = AUDIT_MQ_NOTIFY; 2252 } 2253 2254 /** 2255 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute 2256 * @mqdes: MQ descriptor 2257 * @mqstat: MQ flags 2258 * 2259 */ 2260 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) 2261 { 2262 struct audit_context *context = audit_context(); 2263 context->mq_getsetattr.mqdes = mqdes; 2264 context->mq_getsetattr.mqstat = *mqstat; 2265 context->type = AUDIT_MQ_GETSETATTR; 2266 } 2267 2268 /** 2269 * __audit_ipc_obj - record audit data for ipc object 2270 * @ipcp: ipc permissions 2271 * 2272 */ 2273 void __audit_ipc_obj(struct kern_ipc_perm *ipcp) 2274 { 2275 struct audit_context *context = audit_context(); 2276 context->ipc.uid = ipcp->uid; 2277 context->ipc.gid = ipcp->gid; 2278 context->ipc.mode = ipcp->mode; 2279 context->ipc.has_perm = 0; 2280 security_ipc_getsecid(ipcp, &context->ipc.osid); 2281 context->type = AUDIT_IPC; 2282 } 2283 2284 /** 2285 * __audit_ipc_set_perm - record audit data for new ipc permissions 2286 * @qbytes: msgq bytes 2287 * @uid: msgq user id 2288 * @gid: msgq group id 2289 * @mode: msgq mode (permissions) 2290 * 2291 * Called only after audit_ipc_obj(). 2292 */ 2293 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode) 2294 { 2295 struct audit_context *context = audit_context(); 2296 2297 context->ipc.qbytes = qbytes; 2298 context->ipc.perm_uid = uid; 2299 context->ipc.perm_gid = gid; 2300 context->ipc.perm_mode = mode; 2301 context->ipc.has_perm = 1; 2302 } 2303 2304 void __audit_bprm(struct linux_binprm *bprm) 2305 { 2306 struct audit_context *context = audit_context(); 2307 2308 context->type = AUDIT_EXECVE; 2309 context->execve.argc = bprm->argc; 2310 } 2311 2312 2313 /** 2314 * __audit_socketcall - record audit data for sys_socketcall 2315 * @nargs: number of args, which should not be more than AUDITSC_ARGS. 2316 * @args: args array 2317 * 2318 */ 2319 int __audit_socketcall(int nargs, unsigned long *args) 2320 { 2321 struct audit_context *context = audit_context(); 2322 2323 if (nargs <= 0 || nargs > AUDITSC_ARGS || !args) 2324 return -EINVAL; 2325 context->type = AUDIT_SOCKETCALL; 2326 context->socketcall.nargs = nargs; 2327 memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long)); 2328 return 0; 2329 } 2330 2331 /** 2332 * __audit_fd_pair - record audit data for pipe and socketpair 2333 * @fd1: the first file descriptor 2334 * @fd2: the second file descriptor 2335 * 2336 */ 2337 void __audit_fd_pair(int fd1, int fd2) 2338 { 2339 struct audit_context *context = audit_context(); 2340 context->fds[0] = fd1; 2341 context->fds[1] = fd2; 2342 } 2343 2344 /** 2345 * __audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto 2346 * @len: data length in user space 2347 * @a: data address in kernel space 2348 * 2349 * Returns 0 for success or NULL context or < 0 on error. 2350 */ 2351 int __audit_sockaddr(int len, void *a) 2352 { 2353 struct audit_context *context = audit_context(); 2354 2355 if (!context->sockaddr) { 2356 void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL); 2357 if (!p) 2358 return -ENOMEM; 2359 context->sockaddr = p; 2360 } 2361 2362 context->sockaddr_len = len; 2363 memcpy(context->sockaddr, a, len); 2364 return 0; 2365 } 2366 2367 void __audit_ptrace(struct task_struct *t) 2368 { 2369 struct audit_context *context = audit_context(); 2370 2371 context->target_pid = task_tgid_nr(t); 2372 context->target_auid = audit_get_loginuid(t); 2373 context->target_uid = task_uid(t); 2374 context->target_sessionid = audit_get_sessionid(t); 2375 security_task_getsecid(t, &context->target_sid); 2376 memcpy(context->target_comm, t->comm, TASK_COMM_LEN); 2377 } 2378 2379 /** 2380 * audit_signal_info_syscall - record signal info for syscalls 2381 * @t: task being signaled 2382 * 2383 * If the audit subsystem is being terminated, record the task (pid) 2384 * and uid that is doing that. 2385 */ 2386 int audit_signal_info_syscall(struct task_struct *t) 2387 { 2388 struct audit_aux_data_pids *axp; 2389 struct audit_context *ctx = audit_context(); 2390 kuid_t t_uid = task_uid(t); 2391 2392 if (!audit_signals || audit_dummy_context()) 2393 return 0; 2394 2395 /* optimize the common case by putting first signal recipient directly 2396 * in audit_context */ 2397 if (!ctx->target_pid) { 2398 ctx->target_pid = task_tgid_nr(t); 2399 ctx->target_auid = audit_get_loginuid(t); 2400 ctx->target_uid = t_uid; 2401 ctx->target_sessionid = audit_get_sessionid(t); 2402 security_task_getsecid(t, &ctx->target_sid); 2403 memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); 2404 return 0; 2405 } 2406 2407 axp = (void *)ctx->aux_pids; 2408 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { 2409 axp = kzalloc(sizeof(*axp), GFP_ATOMIC); 2410 if (!axp) 2411 return -ENOMEM; 2412 2413 axp->d.type = AUDIT_OBJ_PID; 2414 axp->d.next = ctx->aux_pids; 2415 ctx->aux_pids = (void *)axp; 2416 } 2417 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); 2418 2419 axp->target_pid[axp->pid_count] = task_tgid_nr(t); 2420 axp->target_auid[axp->pid_count] = audit_get_loginuid(t); 2421 axp->target_uid[axp->pid_count] = t_uid; 2422 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); 2423 security_task_getsecid(t, &axp->target_sid[axp->pid_count]); 2424 memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); 2425 axp->pid_count++; 2426 2427 return 0; 2428 } 2429 2430 /** 2431 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps 2432 * @bprm: pointer to the bprm being processed 2433 * @new: the proposed new credentials 2434 * @old: the old credentials 2435 * 2436 * Simply check if the proc already has the caps given by the file and if not 2437 * store the priv escalation info for later auditing at the end of the syscall 2438 * 2439 * -Eric 2440 */ 2441 int __audit_log_bprm_fcaps(struct linux_binprm *bprm, 2442 const struct cred *new, const struct cred *old) 2443 { 2444 struct audit_aux_data_bprm_fcaps *ax; 2445 struct audit_context *context = audit_context(); 2446 struct cpu_vfs_cap_data vcaps; 2447 2448 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2449 if (!ax) 2450 return -ENOMEM; 2451 2452 ax->d.type = AUDIT_BPRM_FCAPS; 2453 ax->d.next = context->aux; 2454 context->aux = (void *)ax; 2455 2456 get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps); 2457 2458 ax->fcap.permitted = vcaps.permitted; 2459 ax->fcap.inheritable = vcaps.inheritable; 2460 ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 2461 ax->fcap.rootid = vcaps.rootid; 2462 ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; 2463 2464 ax->old_pcap.permitted = old->cap_permitted; 2465 ax->old_pcap.inheritable = old->cap_inheritable; 2466 ax->old_pcap.effective = old->cap_effective; 2467 ax->old_pcap.ambient = old->cap_ambient; 2468 2469 ax->new_pcap.permitted = new->cap_permitted; 2470 ax->new_pcap.inheritable = new->cap_inheritable; 2471 ax->new_pcap.effective = new->cap_effective; 2472 ax->new_pcap.ambient = new->cap_ambient; 2473 return 0; 2474 } 2475 2476 /** 2477 * __audit_log_capset - store information about the arguments to the capset syscall 2478 * @new: the new credentials 2479 * @old: the old (current) credentials 2480 * 2481 * Record the arguments userspace sent to sys_capset for later printing by the 2482 * audit system if applicable 2483 */ 2484 void __audit_log_capset(const struct cred *new, const struct cred *old) 2485 { 2486 struct audit_context *context = audit_context(); 2487 context->capset.pid = task_tgid_nr(current); 2488 context->capset.cap.effective = new->cap_effective; 2489 context->capset.cap.inheritable = new->cap_effective; 2490 context->capset.cap.permitted = new->cap_permitted; 2491 context->capset.cap.ambient = new->cap_ambient; 2492 context->type = AUDIT_CAPSET; 2493 } 2494 2495 void __audit_mmap_fd(int fd, int flags) 2496 { 2497 struct audit_context *context = audit_context(); 2498 context->mmap.fd = fd; 2499 context->mmap.flags = flags; 2500 context->type = AUDIT_MMAP; 2501 } 2502 2503 void __audit_log_kern_module(char *name) 2504 { 2505 struct audit_context *context = audit_context(); 2506 2507 context->module.name = kstrdup(name, GFP_KERNEL); 2508 if (!context->module.name) 2509 audit_log_lost("out of memory in __audit_log_kern_module"); 2510 context->type = AUDIT_KERN_MODULE; 2511 } 2512 2513 void __audit_fanotify(unsigned int response) 2514 { 2515 audit_log(audit_context(), GFP_KERNEL, 2516 AUDIT_FANOTIFY, "resp=%u", response); 2517 } 2518 2519 void __audit_tk_injoffset(struct timespec64 offset) 2520 { 2521 audit_log(audit_context(), GFP_KERNEL, AUDIT_TIME_INJOFFSET, 2522 "sec=%lli nsec=%li", 2523 (long long)offset.tv_sec, offset.tv_nsec); 2524 } 2525 2526 static void audit_log_ntp_val(const struct audit_ntp_data *ad, 2527 const char *op, enum audit_ntp_type type) 2528 { 2529 const struct audit_ntp_val *val = &ad->vals[type]; 2530 2531 if (val->newval == val->oldval) 2532 return; 2533 2534 audit_log(audit_context(), GFP_KERNEL, AUDIT_TIME_ADJNTPVAL, 2535 "op=%s old=%lli new=%lli", op, val->oldval, val->newval); 2536 } 2537 2538 void __audit_ntp_log(const struct audit_ntp_data *ad) 2539 { 2540 audit_log_ntp_val(ad, "offset", AUDIT_NTP_OFFSET); 2541 audit_log_ntp_val(ad, "freq", AUDIT_NTP_FREQ); 2542 audit_log_ntp_val(ad, "status", AUDIT_NTP_STATUS); 2543 audit_log_ntp_val(ad, "tai", AUDIT_NTP_TAI); 2544 audit_log_ntp_val(ad, "tick", AUDIT_NTP_TICK); 2545 audit_log_ntp_val(ad, "adjust", AUDIT_NTP_ADJUST); 2546 } 2547 2548 static void audit_log_task(struct audit_buffer *ab) 2549 { 2550 kuid_t auid, uid; 2551 kgid_t gid; 2552 unsigned int sessionid; 2553 char comm[sizeof(current->comm)]; 2554 2555 auid = audit_get_loginuid(current); 2556 sessionid = audit_get_sessionid(current); 2557 current_uid_gid(&uid, &gid); 2558 2559 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", 2560 from_kuid(&init_user_ns, auid), 2561 from_kuid(&init_user_ns, uid), 2562 from_kgid(&init_user_ns, gid), 2563 sessionid); 2564 audit_log_task_context(ab); 2565 audit_log_format(ab, " pid=%d comm=", task_tgid_nr(current)); 2566 audit_log_untrustedstring(ab, get_task_comm(comm, current)); 2567 audit_log_d_path_exe(ab, current->mm); 2568 } 2569 2570 /** 2571 * audit_core_dumps - record information about processes that end abnormally 2572 * @signr: signal value 2573 * 2574 * If a process ends with a core dump, something fishy is going on and we 2575 * should record the event for investigation. 2576 */ 2577 void audit_core_dumps(long signr) 2578 { 2579 struct audit_buffer *ab; 2580 2581 if (!audit_enabled) 2582 return; 2583 2584 if (signr == SIGQUIT) /* don't care for those */ 2585 return; 2586 2587 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_ANOM_ABEND); 2588 if (unlikely(!ab)) 2589 return; 2590 audit_log_task(ab); 2591 audit_log_format(ab, " sig=%ld res=1", signr); 2592 audit_log_end(ab); 2593 } 2594 2595 /** 2596 * audit_seccomp - record information about a seccomp action 2597 * @syscall: syscall number 2598 * @signr: signal value 2599 * @code: the seccomp action 2600 * 2601 * Record the information associated with a seccomp action. Event filtering for 2602 * seccomp actions that are not to be logged is done in seccomp_log(). 2603 * Therefore, this function forces auditing independent of the audit_enabled 2604 * and dummy context state because seccomp actions should be logged even when 2605 * audit is not in use. 2606 */ 2607 void audit_seccomp(unsigned long syscall, long signr, int code) 2608 { 2609 struct audit_buffer *ab; 2610 2611 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_SECCOMP); 2612 if (unlikely(!ab)) 2613 return; 2614 audit_log_task(ab); 2615 audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x", 2616 signr, syscall_get_arch(current), syscall, 2617 in_compat_syscall(), KSTK_EIP(current), code); 2618 audit_log_end(ab); 2619 } 2620 2621 void audit_seccomp_actions_logged(const char *names, const char *old_names, 2622 int res) 2623 { 2624 struct audit_buffer *ab; 2625 2626 if (!audit_enabled) 2627 return; 2628 2629 ab = audit_log_start(audit_context(), GFP_KERNEL, 2630 AUDIT_CONFIG_CHANGE); 2631 if (unlikely(!ab)) 2632 return; 2633 2634 audit_log_format(ab, 2635 "op=seccomp-logging actions=%s old-actions=%s res=%d", 2636 names, old_names, res); 2637 audit_log_end(ab); 2638 } 2639 2640 struct list_head *audit_killed_trees(void) 2641 { 2642 struct audit_context *ctx = audit_context(); 2643 if (likely(!ctx || !ctx->in_syscall)) 2644 return NULL; 2645 return &ctx->killed_trees; 2646 } 2647