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 struct audit_nfcfgop_tab { 134 enum audit_nfcfgop op; 135 const char *s; 136 }; 137 138 static const struct audit_nfcfgop_tab audit_nfcfgs[] = { 139 { AUDIT_XT_OP_REGISTER, "register" }, 140 { AUDIT_XT_OP_REPLACE, "replace" }, 141 { AUDIT_XT_OP_UNREGISTER, "unregister" }, 142 }; 143 144 static int audit_match_perm(struct audit_context *ctx, int mask) 145 { 146 unsigned n; 147 if (unlikely(!ctx)) 148 return 0; 149 n = ctx->major; 150 151 switch (audit_classify_syscall(ctx->arch, n)) { 152 case 0: /* native */ 153 if ((mask & AUDIT_PERM_WRITE) && 154 audit_match_class(AUDIT_CLASS_WRITE, n)) 155 return 1; 156 if ((mask & AUDIT_PERM_READ) && 157 audit_match_class(AUDIT_CLASS_READ, n)) 158 return 1; 159 if ((mask & AUDIT_PERM_ATTR) && 160 audit_match_class(AUDIT_CLASS_CHATTR, n)) 161 return 1; 162 return 0; 163 case 1: /* 32bit on biarch */ 164 if ((mask & AUDIT_PERM_WRITE) && 165 audit_match_class(AUDIT_CLASS_WRITE_32, n)) 166 return 1; 167 if ((mask & AUDIT_PERM_READ) && 168 audit_match_class(AUDIT_CLASS_READ_32, n)) 169 return 1; 170 if ((mask & AUDIT_PERM_ATTR) && 171 audit_match_class(AUDIT_CLASS_CHATTR_32, n)) 172 return 1; 173 return 0; 174 case 2: /* open */ 175 return mask & ACC_MODE(ctx->argv[1]); 176 case 3: /* openat */ 177 return mask & ACC_MODE(ctx->argv[2]); 178 case 4: /* socketcall */ 179 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); 180 case 5: /* execve */ 181 return mask & AUDIT_PERM_EXEC; 182 default: 183 return 0; 184 } 185 } 186 187 static int audit_match_filetype(struct audit_context *ctx, int val) 188 { 189 struct audit_names *n; 190 umode_t mode = (umode_t)val; 191 192 if (unlikely(!ctx)) 193 return 0; 194 195 list_for_each_entry(n, &ctx->names_list, list) { 196 if ((n->ino != AUDIT_INO_UNSET) && 197 ((n->mode & S_IFMT) == mode)) 198 return 1; 199 } 200 201 return 0; 202 } 203 204 /* 205 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *; 206 * ->first_trees points to its beginning, ->trees - to the current end of data. 207 * ->tree_count is the number of free entries in array pointed to by ->trees. 208 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL, 209 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously, 210 * it's going to remain 1-element for almost any setup) until we free context itself. 211 * References in it _are_ dropped - at the same time we free/drop aux stuff. 212 */ 213 214 static void audit_set_auditable(struct audit_context *ctx) 215 { 216 if (!ctx->prio) { 217 ctx->prio = 1; 218 ctx->current_state = AUDIT_RECORD_CONTEXT; 219 } 220 } 221 222 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk) 223 { 224 struct audit_tree_refs *p = ctx->trees; 225 int left = ctx->tree_count; 226 if (likely(left)) { 227 p->c[--left] = chunk; 228 ctx->tree_count = left; 229 return 1; 230 } 231 if (!p) 232 return 0; 233 p = p->next; 234 if (p) { 235 p->c[30] = chunk; 236 ctx->trees = p; 237 ctx->tree_count = 30; 238 return 1; 239 } 240 return 0; 241 } 242 243 static int grow_tree_refs(struct audit_context *ctx) 244 { 245 struct audit_tree_refs *p = ctx->trees; 246 ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL); 247 if (!ctx->trees) { 248 ctx->trees = p; 249 return 0; 250 } 251 if (p) 252 p->next = ctx->trees; 253 else 254 ctx->first_trees = ctx->trees; 255 ctx->tree_count = 31; 256 return 1; 257 } 258 259 static void unroll_tree_refs(struct audit_context *ctx, 260 struct audit_tree_refs *p, int count) 261 { 262 struct audit_tree_refs *q; 263 int n; 264 if (!p) { 265 /* we started with empty chain */ 266 p = ctx->first_trees; 267 count = 31; 268 /* if the very first allocation has failed, nothing to do */ 269 if (!p) 270 return; 271 } 272 n = count; 273 for (q = p; q != ctx->trees; q = q->next, n = 31) { 274 while (n--) { 275 audit_put_chunk(q->c[n]); 276 q->c[n] = NULL; 277 } 278 } 279 while (n-- > ctx->tree_count) { 280 audit_put_chunk(q->c[n]); 281 q->c[n] = NULL; 282 } 283 ctx->trees = p; 284 ctx->tree_count = count; 285 } 286 287 static void free_tree_refs(struct audit_context *ctx) 288 { 289 struct audit_tree_refs *p, *q; 290 for (p = ctx->first_trees; p; p = q) { 291 q = p->next; 292 kfree(p); 293 } 294 } 295 296 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree) 297 { 298 struct audit_tree_refs *p; 299 int n; 300 if (!tree) 301 return 0; 302 /* full ones */ 303 for (p = ctx->first_trees; p != ctx->trees; p = p->next) { 304 for (n = 0; n < 31; n++) 305 if (audit_tree_match(p->c[n], tree)) 306 return 1; 307 } 308 /* partial */ 309 if (p) { 310 for (n = ctx->tree_count; n < 31; n++) 311 if (audit_tree_match(p->c[n], tree)) 312 return 1; 313 } 314 return 0; 315 } 316 317 static int audit_compare_uid(kuid_t uid, 318 struct audit_names *name, 319 struct audit_field *f, 320 struct audit_context *ctx) 321 { 322 struct audit_names *n; 323 int rc; 324 325 if (name) { 326 rc = audit_uid_comparator(uid, f->op, name->uid); 327 if (rc) 328 return rc; 329 } 330 331 if (ctx) { 332 list_for_each_entry(n, &ctx->names_list, list) { 333 rc = audit_uid_comparator(uid, f->op, n->uid); 334 if (rc) 335 return rc; 336 } 337 } 338 return 0; 339 } 340 341 static int audit_compare_gid(kgid_t gid, 342 struct audit_names *name, 343 struct audit_field *f, 344 struct audit_context *ctx) 345 { 346 struct audit_names *n; 347 int rc; 348 349 if (name) { 350 rc = audit_gid_comparator(gid, f->op, name->gid); 351 if (rc) 352 return rc; 353 } 354 355 if (ctx) { 356 list_for_each_entry(n, &ctx->names_list, list) { 357 rc = audit_gid_comparator(gid, f->op, n->gid); 358 if (rc) 359 return rc; 360 } 361 } 362 return 0; 363 } 364 365 static int audit_field_compare(struct task_struct *tsk, 366 const struct cred *cred, 367 struct audit_field *f, 368 struct audit_context *ctx, 369 struct audit_names *name) 370 { 371 switch (f->val) { 372 /* process to file object comparisons */ 373 case AUDIT_COMPARE_UID_TO_OBJ_UID: 374 return audit_compare_uid(cred->uid, name, f, ctx); 375 case AUDIT_COMPARE_GID_TO_OBJ_GID: 376 return audit_compare_gid(cred->gid, name, f, ctx); 377 case AUDIT_COMPARE_EUID_TO_OBJ_UID: 378 return audit_compare_uid(cred->euid, name, f, ctx); 379 case AUDIT_COMPARE_EGID_TO_OBJ_GID: 380 return audit_compare_gid(cred->egid, name, f, ctx); 381 case AUDIT_COMPARE_AUID_TO_OBJ_UID: 382 return audit_compare_uid(audit_get_loginuid(tsk), name, f, ctx); 383 case AUDIT_COMPARE_SUID_TO_OBJ_UID: 384 return audit_compare_uid(cred->suid, name, f, ctx); 385 case AUDIT_COMPARE_SGID_TO_OBJ_GID: 386 return audit_compare_gid(cred->sgid, name, f, ctx); 387 case AUDIT_COMPARE_FSUID_TO_OBJ_UID: 388 return audit_compare_uid(cred->fsuid, name, f, ctx); 389 case AUDIT_COMPARE_FSGID_TO_OBJ_GID: 390 return audit_compare_gid(cred->fsgid, name, f, ctx); 391 /* uid comparisons */ 392 case AUDIT_COMPARE_UID_TO_AUID: 393 return audit_uid_comparator(cred->uid, f->op, 394 audit_get_loginuid(tsk)); 395 case AUDIT_COMPARE_UID_TO_EUID: 396 return audit_uid_comparator(cred->uid, f->op, cred->euid); 397 case AUDIT_COMPARE_UID_TO_SUID: 398 return audit_uid_comparator(cred->uid, f->op, cred->suid); 399 case AUDIT_COMPARE_UID_TO_FSUID: 400 return audit_uid_comparator(cred->uid, f->op, cred->fsuid); 401 /* auid comparisons */ 402 case AUDIT_COMPARE_AUID_TO_EUID: 403 return audit_uid_comparator(audit_get_loginuid(tsk), f->op, 404 cred->euid); 405 case AUDIT_COMPARE_AUID_TO_SUID: 406 return audit_uid_comparator(audit_get_loginuid(tsk), f->op, 407 cred->suid); 408 case AUDIT_COMPARE_AUID_TO_FSUID: 409 return audit_uid_comparator(audit_get_loginuid(tsk), f->op, 410 cred->fsuid); 411 /* euid comparisons */ 412 case AUDIT_COMPARE_EUID_TO_SUID: 413 return audit_uid_comparator(cred->euid, f->op, cred->suid); 414 case AUDIT_COMPARE_EUID_TO_FSUID: 415 return audit_uid_comparator(cred->euid, f->op, cred->fsuid); 416 /* suid comparisons */ 417 case AUDIT_COMPARE_SUID_TO_FSUID: 418 return audit_uid_comparator(cred->suid, f->op, cred->fsuid); 419 /* gid comparisons */ 420 case AUDIT_COMPARE_GID_TO_EGID: 421 return audit_gid_comparator(cred->gid, f->op, cred->egid); 422 case AUDIT_COMPARE_GID_TO_SGID: 423 return audit_gid_comparator(cred->gid, f->op, cred->sgid); 424 case AUDIT_COMPARE_GID_TO_FSGID: 425 return audit_gid_comparator(cred->gid, f->op, cred->fsgid); 426 /* egid comparisons */ 427 case AUDIT_COMPARE_EGID_TO_SGID: 428 return audit_gid_comparator(cred->egid, f->op, cred->sgid); 429 case AUDIT_COMPARE_EGID_TO_FSGID: 430 return audit_gid_comparator(cred->egid, f->op, cred->fsgid); 431 /* sgid comparison */ 432 case AUDIT_COMPARE_SGID_TO_FSGID: 433 return audit_gid_comparator(cred->sgid, f->op, cred->fsgid); 434 default: 435 WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n"); 436 return 0; 437 } 438 return 0; 439 } 440 441 /* Determine if any context name data matches a rule's watch data */ 442 /* Compare a task_struct with an audit_rule. Return 1 on match, 0 443 * otherwise. 444 * 445 * If task_creation is true, this is an explicit indication that we are 446 * filtering a task rule at task creation time. This and tsk == current are 447 * the only situations where tsk->cred may be accessed without an rcu read lock. 448 */ 449 static int audit_filter_rules(struct task_struct *tsk, 450 struct audit_krule *rule, 451 struct audit_context *ctx, 452 struct audit_names *name, 453 enum audit_state *state, 454 bool task_creation) 455 { 456 const struct cred *cred; 457 int i, need_sid = 1; 458 u32 sid; 459 unsigned int sessionid; 460 461 cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation); 462 463 for (i = 0; i < rule->field_count; i++) { 464 struct audit_field *f = &rule->fields[i]; 465 struct audit_names *n; 466 int result = 0; 467 pid_t pid; 468 469 switch (f->type) { 470 case AUDIT_PID: 471 pid = task_tgid_nr(tsk); 472 result = audit_comparator(pid, f->op, f->val); 473 break; 474 case AUDIT_PPID: 475 if (ctx) { 476 if (!ctx->ppid) 477 ctx->ppid = task_ppid_nr(tsk); 478 result = audit_comparator(ctx->ppid, f->op, f->val); 479 } 480 break; 481 case AUDIT_EXE: 482 result = audit_exe_compare(tsk, rule->exe); 483 if (f->op == Audit_not_equal) 484 result = !result; 485 break; 486 case AUDIT_UID: 487 result = audit_uid_comparator(cred->uid, f->op, f->uid); 488 break; 489 case AUDIT_EUID: 490 result = audit_uid_comparator(cred->euid, f->op, f->uid); 491 break; 492 case AUDIT_SUID: 493 result = audit_uid_comparator(cred->suid, f->op, f->uid); 494 break; 495 case AUDIT_FSUID: 496 result = audit_uid_comparator(cred->fsuid, f->op, f->uid); 497 break; 498 case AUDIT_GID: 499 result = audit_gid_comparator(cred->gid, f->op, f->gid); 500 if (f->op == Audit_equal) { 501 if (!result) 502 result = groups_search(cred->group_info, f->gid); 503 } else if (f->op == Audit_not_equal) { 504 if (result) 505 result = !groups_search(cred->group_info, f->gid); 506 } 507 break; 508 case AUDIT_EGID: 509 result = audit_gid_comparator(cred->egid, f->op, f->gid); 510 if (f->op == Audit_equal) { 511 if (!result) 512 result = groups_search(cred->group_info, f->gid); 513 } else if (f->op == Audit_not_equal) { 514 if (result) 515 result = !groups_search(cred->group_info, f->gid); 516 } 517 break; 518 case AUDIT_SGID: 519 result = audit_gid_comparator(cred->sgid, f->op, f->gid); 520 break; 521 case AUDIT_FSGID: 522 result = audit_gid_comparator(cred->fsgid, f->op, f->gid); 523 break; 524 case AUDIT_SESSIONID: 525 sessionid = audit_get_sessionid(tsk); 526 result = audit_comparator(sessionid, f->op, f->val); 527 break; 528 case AUDIT_PERS: 529 result = audit_comparator(tsk->personality, f->op, f->val); 530 break; 531 case AUDIT_ARCH: 532 if (ctx) 533 result = audit_comparator(ctx->arch, f->op, f->val); 534 break; 535 536 case AUDIT_EXIT: 537 if (ctx && ctx->return_valid) 538 result = audit_comparator(ctx->return_code, f->op, f->val); 539 break; 540 case AUDIT_SUCCESS: 541 if (ctx && ctx->return_valid) { 542 if (f->val) 543 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS); 544 else 545 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE); 546 } 547 break; 548 case AUDIT_DEVMAJOR: 549 if (name) { 550 if (audit_comparator(MAJOR(name->dev), f->op, f->val) || 551 audit_comparator(MAJOR(name->rdev), f->op, f->val)) 552 ++result; 553 } else if (ctx) { 554 list_for_each_entry(n, &ctx->names_list, list) { 555 if (audit_comparator(MAJOR(n->dev), f->op, f->val) || 556 audit_comparator(MAJOR(n->rdev), f->op, f->val)) { 557 ++result; 558 break; 559 } 560 } 561 } 562 break; 563 case AUDIT_DEVMINOR: 564 if (name) { 565 if (audit_comparator(MINOR(name->dev), f->op, f->val) || 566 audit_comparator(MINOR(name->rdev), f->op, f->val)) 567 ++result; 568 } else if (ctx) { 569 list_for_each_entry(n, &ctx->names_list, list) { 570 if (audit_comparator(MINOR(n->dev), f->op, f->val) || 571 audit_comparator(MINOR(n->rdev), f->op, f->val)) { 572 ++result; 573 break; 574 } 575 } 576 } 577 break; 578 case AUDIT_INODE: 579 if (name) 580 result = audit_comparator(name->ino, f->op, f->val); 581 else if (ctx) { 582 list_for_each_entry(n, &ctx->names_list, list) { 583 if (audit_comparator(n->ino, f->op, f->val)) { 584 ++result; 585 break; 586 } 587 } 588 } 589 break; 590 case AUDIT_OBJ_UID: 591 if (name) { 592 result = audit_uid_comparator(name->uid, f->op, f->uid); 593 } else if (ctx) { 594 list_for_each_entry(n, &ctx->names_list, list) { 595 if (audit_uid_comparator(n->uid, f->op, f->uid)) { 596 ++result; 597 break; 598 } 599 } 600 } 601 break; 602 case AUDIT_OBJ_GID: 603 if (name) { 604 result = audit_gid_comparator(name->gid, f->op, f->gid); 605 } else if (ctx) { 606 list_for_each_entry(n, &ctx->names_list, list) { 607 if (audit_gid_comparator(n->gid, f->op, f->gid)) { 608 ++result; 609 break; 610 } 611 } 612 } 613 break; 614 case AUDIT_WATCH: 615 if (name) { 616 result = audit_watch_compare(rule->watch, 617 name->ino, 618 name->dev); 619 if (f->op == Audit_not_equal) 620 result = !result; 621 } 622 break; 623 case AUDIT_DIR: 624 if (ctx) { 625 result = match_tree_refs(ctx, rule->tree); 626 if (f->op == Audit_not_equal) 627 result = !result; 628 } 629 break; 630 case AUDIT_LOGINUID: 631 result = audit_uid_comparator(audit_get_loginuid(tsk), 632 f->op, f->uid); 633 break; 634 case AUDIT_LOGINUID_SET: 635 result = audit_comparator(audit_loginuid_set(tsk), f->op, f->val); 636 break; 637 case AUDIT_SADDR_FAM: 638 if (ctx->sockaddr) 639 result = audit_comparator(ctx->sockaddr->ss_family, 640 f->op, f->val); 641 break; 642 case AUDIT_SUBJ_USER: 643 case AUDIT_SUBJ_ROLE: 644 case AUDIT_SUBJ_TYPE: 645 case AUDIT_SUBJ_SEN: 646 case AUDIT_SUBJ_CLR: 647 /* NOTE: this may return negative values indicating 648 a temporary error. We simply treat this as a 649 match for now to avoid losing information that 650 may be wanted. An error message will also be 651 logged upon error */ 652 if (f->lsm_rule) { 653 if (need_sid) { 654 security_task_getsecid(tsk, &sid); 655 need_sid = 0; 656 } 657 result = security_audit_rule_match(sid, f->type, 658 f->op, 659 f->lsm_rule); 660 } 661 break; 662 case AUDIT_OBJ_USER: 663 case AUDIT_OBJ_ROLE: 664 case AUDIT_OBJ_TYPE: 665 case AUDIT_OBJ_LEV_LOW: 666 case AUDIT_OBJ_LEV_HIGH: 667 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR 668 also applies here */ 669 if (f->lsm_rule) { 670 /* Find files that match */ 671 if (name) { 672 result = security_audit_rule_match( 673 name->osid, 674 f->type, 675 f->op, 676 f->lsm_rule); 677 } else if (ctx) { 678 list_for_each_entry(n, &ctx->names_list, list) { 679 if (security_audit_rule_match( 680 n->osid, 681 f->type, 682 f->op, 683 f->lsm_rule)) { 684 ++result; 685 break; 686 } 687 } 688 } 689 /* Find ipc objects that match */ 690 if (!ctx || ctx->type != AUDIT_IPC) 691 break; 692 if (security_audit_rule_match(ctx->ipc.osid, 693 f->type, f->op, 694 f->lsm_rule)) 695 ++result; 696 } 697 break; 698 case AUDIT_ARG0: 699 case AUDIT_ARG1: 700 case AUDIT_ARG2: 701 case AUDIT_ARG3: 702 if (ctx) 703 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val); 704 break; 705 case AUDIT_FILTERKEY: 706 /* ignore this field for filtering */ 707 result = 1; 708 break; 709 case AUDIT_PERM: 710 result = audit_match_perm(ctx, f->val); 711 if (f->op == Audit_not_equal) 712 result = !result; 713 break; 714 case AUDIT_FILETYPE: 715 result = audit_match_filetype(ctx, f->val); 716 if (f->op == Audit_not_equal) 717 result = !result; 718 break; 719 case AUDIT_FIELD_COMPARE: 720 result = audit_field_compare(tsk, cred, f, ctx, name); 721 break; 722 } 723 if (!result) 724 return 0; 725 } 726 727 if (ctx) { 728 if (rule->prio <= ctx->prio) 729 return 0; 730 if (rule->filterkey) { 731 kfree(ctx->filterkey); 732 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC); 733 } 734 ctx->prio = rule->prio; 735 } 736 switch (rule->action) { 737 case AUDIT_NEVER: 738 *state = AUDIT_DISABLED; 739 break; 740 case AUDIT_ALWAYS: 741 *state = AUDIT_RECORD_CONTEXT; 742 break; 743 } 744 return 1; 745 } 746 747 /* At process creation time, we can determine if system-call auditing is 748 * completely disabled for this task. Since we only have the task 749 * structure at this point, we can only check uid and gid. 750 */ 751 static enum audit_state audit_filter_task(struct task_struct *tsk, char **key) 752 { 753 struct audit_entry *e; 754 enum audit_state state; 755 756 rcu_read_lock(); 757 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { 758 if (audit_filter_rules(tsk, &e->rule, NULL, NULL, 759 &state, true)) { 760 if (state == AUDIT_RECORD_CONTEXT) 761 *key = kstrdup(e->rule.filterkey, GFP_ATOMIC); 762 rcu_read_unlock(); 763 return state; 764 } 765 } 766 rcu_read_unlock(); 767 return AUDIT_BUILD_CONTEXT; 768 } 769 770 static int audit_in_mask(const struct audit_krule *rule, unsigned long val) 771 { 772 int word, bit; 773 774 if (val > 0xffffffff) 775 return false; 776 777 word = AUDIT_WORD(val); 778 if (word >= AUDIT_BITMASK_SIZE) 779 return false; 780 781 bit = AUDIT_BIT(val); 782 783 return rule->mask[word] & bit; 784 } 785 786 /* At syscall entry and exit time, this filter is called if the 787 * audit_state is not low enough that auditing cannot take place, but is 788 * also not high enough that we already know we have to write an audit 789 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). 790 */ 791 static enum audit_state audit_filter_syscall(struct task_struct *tsk, 792 struct audit_context *ctx, 793 struct list_head *list) 794 { 795 struct audit_entry *e; 796 enum audit_state state; 797 798 if (auditd_test_task(tsk)) 799 return AUDIT_DISABLED; 800 801 rcu_read_lock(); 802 list_for_each_entry_rcu(e, list, list) { 803 if (audit_in_mask(&e->rule, ctx->major) && 804 audit_filter_rules(tsk, &e->rule, ctx, NULL, 805 &state, false)) { 806 rcu_read_unlock(); 807 ctx->current_state = state; 808 return state; 809 } 810 } 811 rcu_read_unlock(); 812 return AUDIT_BUILD_CONTEXT; 813 } 814 815 /* 816 * Given an audit_name check the inode hash table to see if they match. 817 * Called holding the rcu read lock to protect the use of audit_inode_hash 818 */ 819 static int audit_filter_inode_name(struct task_struct *tsk, 820 struct audit_names *n, 821 struct audit_context *ctx) { 822 int h = audit_hash_ino((u32)n->ino); 823 struct list_head *list = &audit_inode_hash[h]; 824 struct audit_entry *e; 825 enum audit_state state; 826 827 list_for_each_entry_rcu(e, list, list) { 828 if (audit_in_mask(&e->rule, ctx->major) && 829 audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) { 830 ctx->current_state = state; 831 return 1; 832 } 833 } 834 return 0; 835 } 836 837 /* At syscall exit time, this filter is called if any audit_names have been 838 * collected during syscall processing. We only check rules in sublists at hash 839 * buckets applicable to the inode numbers in audit_names. 840 * Regarding audit_state, same rules apply as for audit_filter_syscall(). 841 */ 842 void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx) 843 { 844 struct audit_names *n; 845 846 if (auditd_test_task(tsk)) 847 return; 848 849 rcu_read_lock(); 850 851 list_for_each_entry(n, &ctx->names_list, list) { 852 if (audit_filter_inode_name(tsk, n, ctx)) 853 break; 854 } 855 rcu_read_unlock(); 856 } 857 858 static inline void audit_proctitle_free(struct audit_context *context) 859 { 860 kfree(context->proctitle.value); 861 context->proctitle.value = NULL; 862 context->proctitle.len = 0; 863 } 864 865 static inline void audit_free_module(struct audit_context *context) 866 { 867 if (context->type == AUDIT_KERN_MODULE) { 868 kfree(context->module.name); 869 context->module.name = NULL; 870 } 871 } 872 static inline void audit_free_names(struct audit_context *context) 873 { 874 struct audit_names *n, *next; 875 876 list_for_each_entry_safe(n, next, &context->names_list, list) { 877 list_del(&n->list); 878 if (n->name) 879 putname(n->name); 880 if (n->should_free) 881 kfree(n); 882 } 883 context->name_count = 0; 884 path_put(&context->pwd); 885 context->pwd.dentry = NULL; 886 context->pwd.mnt = NULL; 887 } 888 889 static inline void audit_free_aux(struct audit_context *context) 890 { 891 struct audit_aux_data *aux; 892 893 while ((aux = context->aux)) { 894 context->aux = aux->next; 895 kfree(aux); 896 } 897 while ((aux = context->aux_pids)) { 898 context->aux_pids = aux->next; 899 kfree(aux); 900 } 901 } 902 903 static inline struct audit_context *audit_alloc_context(enum audit_state state) 904 { 905 struct audit_context *context; 906 907 context = kzalloc(sizeof(*context), GFP_KERNEL); 908 if (!context) 909 return NULL; 910 context->state = state; 911 context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 912 INIT_LIST_HEAD(&context->killed_trees); 913 INIT_LIST_HEAD(&context->names_list); 914 return context; 915 } 916 917 /** 918 * audit_alloc - allocate an audit context block for a task 919 * @tsk: task 920 * 921 * Filter on the task information and allocate a per-task audit context 922 * if necessary. Doing so turns on system call auditing for the 923 * specified task. This is called from copy_process, so no lock is 924 * needed. 925 */ 926 int audit_alloc(struct task_struct *tsk) 927 { 928 struct audit_context *context; 929 enum audit_state state; 930 char *key = NULL; 931 932 if (likely(!audit_ever_enabled)) 933 return 0; /* Return if not auditing. */ 934 935 state = audit_filter_task(tsk, &key); 936 if (state == AUDIT_DISABLED) { 937 clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); 938 return 0; 939 } 940 941 if (!(context = audit_alloc_context(state))) { 942 kfree(key); 943 audit_log_lost("out of memory in audit_alloc"); 944 return -ENOMEM; 945 } 946 context->filterkey = key; 947 948 audit_set_context(tsk, context); 949 set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); 950 return 0; 951 } 952 953 static inline void audit_free_context(struct audit_context *context) 954 { 955 audit_free_module(context); 956 audit_free_names(context); 957 unroll_tree_refs(context, NULL, 0); 958 free_tree_refs(context); 959 audit_free_aux(context); 960 kfree(context->filterkey); 961 kfree(context->sockaddr); 962 audit_proctitle_free(context); 963 kfree(context); 964 } 965 966 static int audit_log_pid_context(struct audit_context *context, pid_t pid, 967 kuid_t auid, kuid_t uid, unsigned int sessionid, 968 u32 sid, char *comm) 969 { 970 struct audit_buffer *ab; 971 char *ctx = NULL; 972 u32 len; 973 int rc = 0; 974 975 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); 976 if (!ab) 977 return rc; 978 979 audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, 980 from_kuid(&init_user_ns, auid), 981 from_kuid(&init_user_ns, uid), sessionid); 982 if (sid) { 983 if (security_secid_to_secctx(sid, &ctx, &len)) { 984 audit_log_format(ab, " obj=(none)"); 985 rc = 1; 986 } else { 987 audit_log_format(ab, " obj=%s", ctx); 988 security_release_secctx(ctx, len); 989 } 990 } 991 audit_log_format(ab, " ocomm="); 992 audit_log_untrustedstring(ab, comm); 993 audit_log_end(ab); 994 995 return rc; 996 } 997 998 static void audit_log_execve_info(struct audit_context *context, 999 struct audit_buffer **ab) 1000 { 1001 long len_max; 1002 long len_rem; 1003 long len_full; 1004 long len_buf; 1005 long len_abuf = 0; 1006 long len_tmp; 1007 bool require_data; 1008 bool encode; 1009 unsigned int iter; 1010 unsigned int arg; 1011 char *buf_head; 1012 char *buf; 1013 const char __user *p = (const char __user *)current->mm->arg_start; 1014 1015 /* NOTE: this buffer needs to be large enough to hold all the non-arg 1016 * data we put in the audit record for this argument (see the 1017 * code below) ... at this point in time 96 is plenty */ 1018 char abuf[96]; 1019 1020 /* NOTE: we set MAX_EXECVE_AUDIT_LEN to a rather arbitrary limit, the 1021 * current value of 7500 is not as important as the fact that it 1022 * is less than 8k, a setting of 7500 gives us plenty of wiggle 1023 * room if we go over a little bit in the logging below */ 1024 WARN_ON_ONCE(MAX_EXECVE_AUDIT_LEN > 7500); 1025 len_max = MAX_EXECVE_AUDIT_LEN; 1026 1027 /* scratch buffer to hold the userspace args */ 1028 buf_head = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL); 1029 if (!buf_head) { 1030 audit_panic("out of memory for argv string"); 1031 return; 1032 } 1033 buf = buf_head; 1034 1035 audit_log_format(*ab, "argc=%d", context->execve.argc); 1036 1037 len_rem = len_max; 1038 len_buf = 0; 1039 len_full = 0; 1040 require_data = true; 1041 encode = false; 1042 iter = 0; 1043 arg = 0; 1044 do { 1045 /* NOTE: we don't ever want to trust this value for anything 1046 * serious, but the audit record format insists we 1047 * provide an argument length for really long arguments, 1048 * e.g. > MAX_EXECVE_AUDIT_LEN, so we have no choice but 1049 * to use strncpy_from_user() to obtain this value for 1050 * recording in the log, although we don't use it 1051 * anywhere here to avoid a double-fetch problem */ 1052 if (len_full == 0) 1053 len_full = strnlen_user(p, MAX_ARG_STRLEN) - 1; 1054 1055 /* read more data from userspace */ 1056 if (require_data) { 1057 /* can we make more room in the buffer? */ 1058 if (buf != buf_head) { 1059 memmove(buf_head, buf, len_buf); 1060 buf = buf_head; 1061 } 1062 1063 /* fetch as much as we can of the argument */ 1064 len_tmp = strncpy_from_user(&buf_head[len_buf], p, 1065 len_max - len_buf); 1066 if (len_tmp == -EFAULT) { 1067 /* unable to copy from userspace */ 1068 send_sig(SIGKILL, current, 0); 1069 goto out; 1070 } else if (len_tmp == (len_max - len_buf)) { 1071 /* buffer is not large enough */ 1072 require_data = true; 1073 /* NOTE: if we are going to span multiple 1074 * buffers force the encoding so we stand 1075 * a chance at a sane len_full value and 1076 * consistent record encoding */ 1077 encode = true; 1078 len_full = len_full * 2; 1079 p += len_tmp; 1080 } else { 1081 require_data = false; 1082 if (!encode) 1083 encode = audit_string_contains_control( 1084 buf, len_tmp); 1085 /* try to use a trusted value for len_full */ 1086 if (len_full < len_max) 1087 len_full = (encode ? 1088 len_tmp * 2 : len_tmp); 1089 p += len_tmp + 1; 1090 } 1091 len_buf += len_tmp; 1092 buf_head[len_buf] = '\0'; 1093 1094 /* length of the buffer in the audit record? */ 1095 len_abuf = (encode ? len_buf * 2 : len_buf + 2); 1096 } 1097 1098 /* write as much as we can to the audit log */ 1099 if (len_buf >= 0) { 1100 /* NOTE: some magic numbers here - basically if we 1101 * can't fit a reasonable amount of data into the 1102 * existing audit buffer, flush it and start with 1103 * a new buffer */ 1104 if ((sizeof(abuf) + 8) > len_rem) { 1105 len_rem = len_max; 1106 audit_log_end(*ab); 1107 *ab = audit_log_start(context, 1108 GFP_KERNEL, AUDIT_EXECVE); 1109 if (!*ab) 1110 goto out; 1111 } 1112 1113 /* create the non-arg portion of the arg record */ 1114 len_tmp = 0; 1115 if (require_data || (iter > 0) || 1116 ((len_abuf + sizeof(abuf)) > len_rem)) { 1117 if (iter == 0) { 1118 len_tmp += snprintf(&abuf[len_tmp], 1119 sizeof(abuf) - len_tmp, 1120 " a%d_len=%lu", 1121 arg, len_full); 1122 } 1123 len_tmp += snprintf(&abuf[len_tmp], 1124 sizeof(abuf) - len_tmp, 1125 " a%d[%d]=", arg, iter++); 1126 } else 1127 len_tmp += snprintf(&abuf[len_tmp], 1128 sizeof(abuf) - len_tmp, 1129 " a%d=", arg); 1130 WARN_ON(len_tmp >= sizeof(abuf)); 1131 abuf[sizeof(abuf) - 1] = '\0'; 1132 1133 /* log the arg in the audit record */ 1134 audit_log_format(*ab, "%s", abuf); 1135 len_rem -= len_tmp; 1136 len_tmp = len_buf; 1137 if (encode) { 1138 if (len_abuf > len_rem) 1139 len_tmp = len_rem / 2; /* encoding */ 1140 audit_log_n_hex(*ab, buf, len_tmp); 1141 len_rem -= len_tmp * 2; 1142 len_abuf -= len_tmp * 2; 1143 } else { 1144 if (len_abuf > len_rem) 1145 len_tmp = len_rem - 2; /* quotes */ 1146 audit_log_n_string(*ab, buf, len_tmp); 1147 len_rem -= len_tmp + 2; 1148 /* don't subtract the "2" because we still need 1149 * to add quotes to the remaining string */ 1150 len_abuf -= len_tmp; 1151 } 1152 len_buf -= len_tmp; 1153 buf += len_tmp; 1154 } 1155 1156 /* ready to move to the next argument? */ 1157 if ((len_buf == 0) && !require_data) { 1158 arg++; 1159 iter = 0; 1160 len_full = 0; 1161 require_data = true; 1162 encode = false; 1163 } 1164 } while (arg < context->execve.argc); 1165 1166 /* NOTE: the caller handles the final audit_log_end() call */ 1167 1168 out: 1169 kfree(buf_head); 1170 } 1171 1172 static void audit_log_cap(struct audit_buffer *ab, char *prefix, 1173 kernel_cap_t *cap) 1174 { 1175 int i; 1176 1177 if (cap_isclear(*cap)) { 1178 audit_log_format(ab, " %s=0", prefix); 1179 return; 1180 } 1181 audit_log_format(ab, " %s=", prefix); 1182 CAP_FOR_EACH_U32(i) 1183 audit_log_format(ab, "%08x", cap->cap[CAP_LAST_U32 - i]); 1184 } 1185 1186 static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) 1187 { 1188 if (name->fcap_ver == -1) { 1189 audit_log_format(ab, " cap_fe=? cap_fver=? cap_fp=? cap_fi=?"); 1190 return; 1191 } 1192 audit_log_cap(ab, "cap_fp", &name->fcap.permitted); 1193 audit_log_cap(ab, "cap_fi", &name->fcap.inheritable); 1194 audit_log_format(ab, " cap_fe=%d cap_fver=%x cap_frootid=%d", 1195 name->fcap.fE, name->fcap_ver, 1196 from_kuid(&init_user_ns, name->fcap.rootid)); 1197 } 1198 1199 static void show_special(struct audit_context *context, int *call_panic) 1200 { 1201 struct audit_buffer *ab; 1202 int i; 1203 1204 ab = audit_log_start(context, GFP_KERNEL, context->type); 1205 if (!ab) 1206 return; 1207 1208 switch (context->type) { 1209 case AUDIT_SOCKETCALL: { 1210 int nargs = context->socketcall.nargs; 1211 audit_log_format(ab, "nargs=%d", nargs); 1212 for (i = 0; i < nargs; i++) 1213 audit_log_format(ab, " a%d=%lx", i, 1214 context->socketcall.args[i]); 1215 break; } 1216 case AUDIT_IPC: { 1217 u32 osid = context->ipc.osid; 1218 1219 audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho", 1220 from_kuid(&init_user_ns, context->ipc.uid), 1221 from_kgid(&init_user_ns, context->ipc.gid), 1222 context->ipc.mode); 1223 if (osid) { 1224 char *ctx = NULL; 1225 u32 len; 1226 if (security_secid_to_secctx(osid, &ctx, &len)) { 1227 audit_log_format(ab, " osid=%u", osid); 1228 *call_panic = 1; 1229 } else { 1230 audit_log_format(ab, " obj=%s", ctx); 1231 security_release_secctx(ctx, len); 1232 } 1233 } 1234 if (context->ipc.has_perm) { 1235 audit_log_end(ab); 1236 ab = audit_log_start(context, GFP_KERNEL, 1237 AUDIT_IPC_SET_PERM); 1238 if (unlikely(!ab)) 1239 return; 1240 audit_log_format(ab, 1241 "qbytes=%lx ouid=%u ogid=%u mode=%#ho", 1242 context->ipc.qbytes, 1243 context->ipc.perm_uid, 1244 context->ipc.perm_gid, 1245 context->ipc.perm_mode); 1246 } 1247 break; } 1248 case AUDIT_MQ_OPEN: 1249 audit_log_format(ab, 1250 "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld " 1251 "mq_msgsize=%ld mq_curmsgs=%ld", 1252 context->mq_open.oflag, context->mq_open.mode, 1253 context->mq_open.attr.mq_flags, 1254 context->mq_open.attr.mq_maxmsg, 1255 context->mq_open.attr.mq_msgsize, 1256 context->mq_open.attr.mq_curmsgs); 1257 break; 1258 case AUDIT_MQ_SENDRECV: 1259 audit_log_format(ab, 1260 "mqdes=%d msg_len=%zd msg_prio=%u " 1261 "abs_timeout_sec=%lld abs_timeout_nsec=%ld", 1262 context->mq_sendrecv.mqdes, 1263 context->mq_sendrecv.msg_len, 1264 context->mq_sendrecv.msg_prio, 1265 (long long) context->mq_sendrecv.abs_timeout.tv_sec, 1266 context->mq_sendrecv.abs_timeout.tv_nsec); 1267 break; 1268 case AUDIT_MQ_NOTIFY: 1269 audit_log_format(ab, "mqdes=%d sigev_signo=%d", 1270 context->mq_notify.mqdes, 1271 context->mq_notify.sigev_signo); 1272 break; 1273 case AUDIT_MQ_GETSETATTR: { 1274 struct mq_attr *attr = &context->mq_getsetattr.mqstat; 1275 audit_log_format(ab, 1276 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld " 1277 "mq_curmsgs=%ld ", 1278 context->mq_getsetattr.mqdes, 1279 attr->mq_flags, attr->mq_maxmsg, 1280 attr->mq_msgsize, attr->mq_curmsgs); 1281 break; } 1282 case AUDIT_CAPSET: 1283 audit_log_format(ab, "pid=%d", context->capset.pid); 1284 audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable); 1285 audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted); 1286 audit_log_cap(ab, "cap_pe", &context->capset.cap.effective); 1287 audit_log_cap(ab, "cap_pa", &context->capset.cap.ambient); 1288 break; 1289 case AUDIT_MMAP: 1290 audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd, 1291 context->mmap.flags); 1292 break; 1293 case AUDIT_EXECVE: 1294 audit_log_execve_info(context, &ab); 1295 break; 1296 case AUDIT_KERN_MODULE: 1297 audit_log_format(ab, "name="); 1298 if (context->module.name) { 1299 audit_log_untrustedstring(ab, context->module.name); 1300 } else 1301 audit_log_format(ab, "(null)"); 1302 1303 break; 1304 } 1305 audit_log_end(ab); 1306 } 1307 1308 static inline int audit_proctitle_rtrim(char *proctitle, int len) 1309 { 1310 char *end = proctitle + len - 1; 1311 while (end > proctitle && !isprint(*end)) 1312 end--; 1313 1314 /* catch the case where proctitle is only 1 non-print character */ 1315 len = end - proctitle + 1; 1316 len -= isprint(proctitle[len-1]) == 0; 1317 return len; 1318 } 1319 1320 /* 1321 * audit_log_name - produce AUDIT_PATH record from struct audit_names 1322 * @context: audit_context for the task 1323 * @n: audit_names structure with reportable details 1324 * @path: optional path to report instead of audit_names->name 1325 * @record_num: record number to report when handling a list of names 1326 * @call_panic: optional pointer to int that will be updated if secid fails 1327 */ 1328 static void audit_log_name(struct audit_context *context, struct audit_names *n, 1329 const struct path *path, int record_num, int *call_panic) 1330 { 1331 struct audit_buffer *ab; 1332 1333 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH); 1334 if (!ab) 1335 return; 1336 1337 audit_log_format(ab, "item=%d", record_num); 1338 1339 if (path) 1340 audit_log_d_path(ab, " name=", path); 1341 else if (n->name) { 1342 switch (n->name_len) { 1343 case AUDIT_NAME_FULL: 1344 /* log the full path */ 1345 audit_log_format(ab, " name="); 1346 audit_log_untrustedstring(ab, n->name->name); 1347 break; 1348 case 0: 1349 /* name was specified as a relative path and the 1350 * directory component is the cwd 1351 */ 1352 audit_log_d_path(ab, " name=", &context->pwd); 1353 break; 1354 default: 1355 /* log the name's directory component */ 1356 audit_log_format(ab, " name="); 1357 audit_log_n_untrustedstring(ab, n->name->name, 1358 n->name_len); 1359 } 1360 } else 1361 audit_log_format(ab, " name=(null)"); 1362 1363 if (n->ino != AUDIT_INO_UNSET) 1364 audit_log_format(ab, " inode=%lu dev=%02x:%02x mode=%#ho ouid=%u ogid=%u rdev=%02x:%02x", 1365 n->ino, 1366 MAJOR(n->dev), 1367 MINOR(n->dev), 1368 n->mode, 1369 from_kuid(&init_user_ns, n->uid), 1370 from_kgid(&init_user_ns, n->gid), 1371 MAJOR(n->rdev), 1372 MINOR(n->rdev)); 1373 if (n->osid != 0) { 1374 char *ctx = NULL; 1375 u32 len; 1376 1377 if (security_secid_to_secctx( 1378 n->osid, &ctx, &len)) { 1379 audit_log_format(ab, " osid=%u", n->osid); 1380 if (call_panic) 1381 *call_panic = 2; 1382 } else { 1383 audit_log_format(ab, " obj=%s", ctx); 1384 security_release_secctx(ctx, len); 1385 } 1386 } 1387 1388 /* log the audit_names record type */ 1389 switch (n->type) { 1390 case AUDIT_TYPE_NORMAL: 1391 audit_log_format(ab, " nametype=NORMAL"); 1392 break; 1393 case AUDIT_TYPE_PARENT: 1394 audit_log_format(ab, " nametype=PARENT"); 1395 break; 1396 case AUDIT_TYPE_CHILD_DELETE: 1397 audit_log_format(ab, " nametype=DELETE"); 1398 break; 1399 case AUDIT_TYPE_CHILD_CREATE: 1400 audit_log_format(ab, " nametype=CREATE"); 1401 break; 1402 default: 1403 audit_log_format(ab, " nametype=UNKNOWN"); 1404 break; 1405 } 1406 1407 audit_log_fcaps(ab, n); 1408 audit_log_end(ab); 1409 } 1410 1411 static void audit_log_proctitle(void) 1412 { 1413 int res; 1414 char *buf; 1415 char *msg = "(null)"; 1416 int len = strlen(msg); 1417 struct audit_context *context = audit_context(); 1418 struct audit_buffer *ab; 1419 1420 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE); 1421 if (!ab) 1422 return; /* audit_panic or being filtered */ 1423 1424 audit_log_format(ab, "proctitle="); 1425 1426 /* Not cached */ 1427 if (!context->proctitle.value) { 1428 buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL); 1429 if (!buf) 1430 goto out; 1431 /* Historically called this from procfs naming */ 1432 res = get_cmdline(current, buf, MAX_PROCTITLE_AUDIT_LEN); 1433 if (res == 0) { 1434 kfree(buf); 1435 goto out; 1436 } 1437 res = audit_proctitle_rtrim(buf, res); 1438 if (res == 0) { 1439 kfree(buf); 1440 goto out; 1441 } 1442 context->proctitle.value = buf; 1443 context->proctitle.len = res; 1444 } 1445 msg = context->proctitle.value; 1446 len = context->proctitle.len; 1447 out: 1448 audit_log_n_untrustedstring(ab, msg, len); 1449 audit_log_end(ab); 1450 } 1451 1452 static void audit_log_exit(void) 1453 { 1454 int i, call_panic = 0; 1455 struct audit_context *context = audit_context(); 1456 struct audit_buffer *ab; 1457 struct audit_aux_data *aux; 1458 struct audit_names *n; 1459 1460 context->personality = current->personality; 1461 1462 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); 1463 if (!ab) 1464 return; /* audit_panic has been called */ 1465 audit_log_format(ab, "arch=%x syscall=%d", 1466 context->arch, context->major); 1467 if (context->personality != PER_LINUX) 1468 audit_log_format(ab, " per=%lx", context->personality); 1469 if (context->return_valid) 1470 audit_log_format(ab, " success=%s exit=%ld", 1471 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", 1472 context->return_code); 1473 1474 audit_log_format(ab, 1475 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d", 1476 context->argv[0], 1477 context->argv[1], 1478 context->argv[2], 1479 context->argv[3], 1480 context->name_count); 1481 1482 audit_log_task_info(ab); 1483 audit_log_key(ab, context->filterkey); 1484 audit_log_end(ab); 1485 1486 for (aux = context->aux; aux; aux = aux->next) { 1487 1488 ab = audit_log_start(context, GFP_KERNEL, aux->type); 1489 if (!ab) 1490 continue; /* audit_panic has been called */ 1491 1492 switch (aux->type) { 1493 1494 case AUDIT_BPRM_FCAPS: { 1495 struct audit_aux_data_bprm_fcaps *axs = (void *)aux; 1496 audit_log_format(ab, "fver=%x", axs->fcap_ver); 1497 audit_log_cap(ab, "fp", &axs->fcap.permitted); 1498 audit_log_cap(ab, "fi", &axs->fcap.inheritable); 1499 audit_log_format(ab, " fe=%d", axs->fcap.fE); 1500 audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted); 1501 audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable); 1502 audit_log_cap(ab, "old_pe", &axs->old_pcap.effective); 1503 audit_log_cap(ab, "old_pa", &axs->old_pcap.ambient); 1504 audit_log_cap(ab, "pp", &axs->new_pcap.permitted); 1505 audit_log_cap(ab, "pi", &axs->new_pcap.inheritable); 1506 audit_log_cap(ab, "pe", &axs->new_pcap.effective); 1507 audit_log_cap(ab, "pa", &axs->new_pcap.ambient); 1508 audit_log_format(ab, " frootid=%d", 1509 from_kuid(&init_user_ns, 1510 axs->fcap.rootid)); 1511 break; } 1512 1513 } 1514 audit_log_end(ab); 1515 } 1516 1517 if (context->type) 1518 show_special(context, &call_panic); 1519 1520 if (context->fds[0] >= 0) { 1521 ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR); 1522 if (ab) { 1523 audit_log_format(ab, "fd0=%d fd1=%d", 1524 context->fds[0], context->fds[1]); 1525 audit_log_end(ab); 1526 } 1527 } 1528 1529 if (context->sockaddr_len) { 1530 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR); 1531 if (ab) { 1532 audit_log_format(ab, "saddr="); 1533 audit_log_n_hex(ab, (void *)context->sockaddr, 1534 context->sockaddr_len); 1535 audit_log_end(ab); 1536 } 1537 } 1538 1539 for (aux = context->aux_pids; aux; aux = aux->next) { 1540 struct audit_aux_data_pids *axs = (void *)aux; 1541 1542 for (i = 0; i < axs->pid_count; i++) 1543 if (audit_log_pid_context(context, axs->target_pid[i], 1544 axs->target_auid[i], 1545 axs->target_uid[i], 1546 axs->target_sessionid[i], 1547 axs->target_sid[i], 1548 axs->target_comm[i])) 1549 call_panic = 1; 1550 } 1551 1552 if (context->target_pid && 1553 audit_log_pid_context(context, context->target_pid, 1554 context->target_auid, context->target_uid, 1555 context->target_sessionid, 1556 context->target_sid, context->target_comm)) 1557 call_panic = 1; 1558 1559 if (context->pwd.dentry && context->pwd.mnt) { 1560 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); 1561 if (ab) { 1562 audit_log_d_path(ab, "cwd=", &context->pwd); 1563 audit_log_end(ab); 1564 } 1565 } 1566 1567 i = 0; 1568 list_for_each_entry(n, &context->names_list, list) { 1569 if (n->hidden) 1570 continue; 1571 audit_log_name(context, n, NULL, i++, &call_panic); 1572 } 1573 1574 audit_log_proctitle(); 1575 1576 /* Send end of event record to help user space know we are finished */ 1577 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); 1578 if (ab) 1579 audit_log_end(ab); 1580 if (call_panic) 1581 audit_panic("error converting sid to string"); 1582 } 1583 1584 /** 1585 * __audit_free - free a per-task audit context 1586 * @tsk: task whose audit context block to free 1587 * 1588 * Called from copy_process and do_exit 1589 */ 1590 void __audit_free(struct task_struct *tsk) 1591 { 1592 struct audit_context *context = tsk->audit_context; 1593 1594 if (!context) 1595 return; 1596 1597 if (!list_empty(&context->killed_trees)) 1598 audit_kill_trees(context); 1599 1600 /* We are called either by do_exit() or the fork() error handling code; 1601 * in the former case tsk == current and in the latter tsk is a 1602 * random task_struct that doesn't doesn't have any meaningful data we 1603 * need to log via audit_log_exit(). 1604 */ 1605 if (tsk == current && !context->dummy && context->in_syscall) { 1606 context->return_valid = 0; 1607 context->return_code = 0; 1608 1609 audit_filter_syscall(tsk, context, 1610 &audit_filter_list[AUDIT_FILTER_EXIT]); 1611 audit_filter_inodes(tsk, context); 1612 if (context->current_state == AUDIT_RECORD_CONTEXT) 1613 audit_log_exit(); 1614 } 1615 1616 audit_set_context(tsk, NULL); 1617 audit_free_context(context); 1618 } 1619 1620 /** 1621 * __audit_syscall_entry - fill in an audit record at syscall entry 1622 * @major: major syscall type (function) 1623 * @a1: additional syscall register 1 1624 * @a2: additional syscall register 2 1625 * @a3: additional syscall register 3 1626 * @a4: additional syscall register 4 1627 * 1628 * Fill in audit context at syscall entry. This only happens if the 1629 * audit context was created when the task was created and the state or 1630 * filters demand the audit context be built. If the state from the 1631 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, 1632 * then the record will be written at syscall exit time (otherwise, it 1633 * will only be written if another part of the kernel requests that it 1634 * be written). 1635 */ 1636 void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2, 1637 unsigned long a3, unsigned long a4) 1638 { 1639 struct audit_context *context = audit_context(); 1640 enum audit_state state; 1641 1642 if (!audit_enabled || !context) 1643 return; 1644 1645 BUG_ON(context->in_syscall || context->name_count); 1646 1647 state = context->state; 1648 if (state == AUDIT_DISABLED) 1649 return; 1650 1651 context->dummy = !audit_n_rules; 1652 if (!context->dummy && state == AUDIT_BUILD_CONTEXT) { 1653 context->prio = 0; 1654 if (auditd_test_task(current)) 1655 return; 1656 } 1657 1658 context->arch = syscall_get_arch(current); 1659 context->major = major; 1660 context->argv[0] = a1; 1661 context->argv[1] = a2; 1662 context->argv[2] = a3; 1663 context->argv[3] = a4; 1664 context->serial = 0; 1665 context->in_syscall = 1; 1666 context->current_state = state; 1667 context->ppid = 0; 1668 ktime_get_coarse_real_ts64(&context->ctime); 1669 } 1670 1671 /** 1672 * __audit_syscall_exit - deallocate audit context after a system call 1673 * @success: success value of the syscall 1674 * @return_code: return value of the syscall 1675 * 1676 * Tear down after system call. If the audit context has been marked as 1677 * auditable (either because of the AUDIT_RECORD_CONTEXT state from 1678 * filtering, or because some other part of the kernel wrote an audit 1679 * message), then write out the syscall information. In call cases, 1680 * free the names stored from getname(). 1681 */ 1682 void __audit_syscall_exit(int success, long return_code) 1683 { 1684 struct audit_context *context; 1685 1686 context = audit_context(); 1687 if (!context) 1688 return; 1689 1690 if (!list_empty(&context->killed_trees)) 1691 audit_kill_trees(context); 1692 1693 if (!context->dummy && context->in_syscall) { 1694 if (success) 1695 context->return_valid = AUDITSC_SUCCESS; 1696 else 1697 context->return_valid = AUDITSC_FAILURE; 1698 1699 /* 1700 * we need to fix up the return code in the audit logs if the 1701 * actual return codes are later going to be fixed up by the 1702 * arch specific signal handlers 1703 * 1704 * This is actually a test for: 1705 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) || 1706 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK) 1707 * 1708 * but is faster than a bunch of || 1709 */ 1710 if (unlikely(return_code <= -ERESTARTSYS) && 1711 (return_code >= -ERESTART_RESTARTBLOCK) && 1712 (return_code != -ENOIOCTLCMD)) 1713 context->return_code = -EINTR; 1714 else 1715 context->return_code = return_code; 1716 1717 audit_filter_syscall(current, context, 1718 &audit_filter_list[AUDIT_FILTER_EXIT]); 1719 audit_filter_inodes(current, context); 1720 if (context->current_state == AUDIT_RECORD_CONTEXT) 1721 audit_log_exit(); 1722 } 1723 1724 context->in_syscall = 0; 1725 context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 1726 1727 audit_free_module(context); 1728 audit_free_names(context); 1729 unroll_tree_refs(context, NULL, 0); 1730 audit_free_aux(context); 1731 context->aux = NULL; 1732 context->aux_pids = NULL; 1733 context->target_pid = 0; 1734 context->target_sid = 0; 1735 context->sockaddr_len = 0; 1736 context->type = 0; 1737 context->fds[0] = -1; 1738 if (context->state != AUDIT_RECORD_CONTEXT) { 1739 kfree(context->filterkey); 1740 context->filterkey = NULL; 1741 } 1742 } 1743 1744 static inline void handle_one(const struct inode *inode) 1745 { 1746 struct audit_context *context; 1747 struct audit_tree_refs *p; 1748 struct audit_chunk *chunk; 1749 int count; 1750 if (likely(!inode->i_fsnotify_marks)) 1751 return; 1752 context = audit_context(); 1753 p = context->trees; 1754 count = context->tree_count; 1755 rcu_read_lock(); 1756 chunk = audit_tree_lookup(inode); 1757 rcu_read_unlock(); 1758 if (!chunk) 1759 return; 1760 if (likely(put_tree_ref(context, chunk))) 1761 return; 1762 if (unlikely(!grow_tree_refs(context))) { 1763 pr_warn("out of memory, audit has lost a tree reference\n"); 1764 audit_set_auditable(context); 1765 audit_put_chunk(chunk); 1766 unroll_tree_refs(context, p, count); 1767 return; 1768 } 1769 put_tree_ref(context, chunk); 1770 } 1771 1772 static void handle_path(const struct dentry *dentry) 1773 { 1774 struct audit_context *context; 1775 struct audit_tree_refs *p; 1776 const struct dentry *d, *parent; 1777 struct audit_chunk *drop; 1778 unsigned long seq; 1779 int count; 1780 1781 context = audit_context(); 1782 p = context->trees; 1783 count = context->tree_count; 1784 retry: 1785 drop = NULL; 1786 d = dentry; 1787 rcu_read_lock(); 1788 seq = read_seqbegin(&rename_lock); 1789 for(;;) { 1790 struct inode *inode = d_backing_inode(d); 1791 if (inode && unlikely(inode->i_fsnotify_marks)) { 1792 struct audit_chunk *chunk; 1793 chunk = audit_tree_lookup(inode); 1794 if (chunk) { 1795 if (unlikely(!put_tree_ref(context, chunk))) { 1796 drop = chunk; 1797 break; 1798 } 1799 } 1800 } 1801 parent = d->d_parent; 1802 if (parent == d) 1803 break; 1804 d = parent; 1805 } 1806 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */ 1807 rcu_read_unlock(); 1808 if (!drop) { 1809 /* just a race with rename */ 1810 unroll_tree_refs(context, p, count); 1811 goto retry; 1812 } 1813 audit_put_chunk(drop); 1814 if (grow_tree_refs(context)) { 1815 /* OK, got more space */ 1816 unroll_tree_refs(context, p, count); 1817 goto retry; 1818 } 1819 /* too bad */ 1820 pr_warn("out of memory, audit has lost a tree reference\n"); 1821 unroll_tree_refs(context, p, count); 1822 audit_set_auditable(context); 1823 return; 1824 } 1825 rcu_read_unlock(); 1826 } 1827 1828 static struct audit_names *audit_alloc_name(struct audit_context *context, 1829 unsigned char type) 1830 { 1831 struct audit_names *aname; 1832 1833 if (context->name_count < AUDIT_NAMES) { 1834 aname = &context->preallocated_names[context->name_count]; 1835 memset(aname, 0, sizeof(*aname)); 1836 } else { 1837 aname = kzalloc(sizeof(*aname), GFP_NOFS); 1838 if (!aname) 1839 return NULL; 1840 aname->should_free = true; 1841 } 1842 1843 aname->ino = AUDIT_INO_UNSET; 1844 aname->type = type; 1845 list_add_tail(&aname->list, &context->names_list); 1846 1847 context->name_count++; 1848 return aname; 1849 } 1850 1851 /** 1852 * __audit_reusename - fill out filename with info from existing entry 1853 * @uptr: userland ptr to pathname 1854 * 1855 * Search the audit_names list for the current audit context. If there is an 1856 * existing entry with a matching "uptr" then return the filename 1857 * associated with that audit_name. If not, return NULL. 1858 */ 1859 struct filename * 1860 __audit_reusename(const __user char *uptr) 1861 { 1862 struct audit_context *context = audit_context(); 1863 struct audit_names *n; 1864 1865 list_for_each_entry(n, &context->names_list, list) { 1866 if (!n->name) 1867 continue; 1868 if (n->name->uptr == uptr) { 1869 n->name->refcnt++; 1870 return n->name; 1871 } 1872 } 1873 return NULL; 1874 } 1875 1876 /** 1877 * __audit_getname - add a name to the list 1878 * @name: name to add 1879 * 1880 * Add a name to the list of audit names for this context. 1881 * Called from fs/namei.c:getname(). 1882 */ 1883 void __audit_getname(struct filename *name) 1884 { 1885 struct audit_context *context = audit_context(); 1886 struct audit_names *n; 1887 1888 if (!context->in_syscall) 1889 return; 1890 1891 n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); 1892 if (!n) 1893 return; 1894 1895 n->name = name; 1896 n->name_len = AUDIT_NAME_FULL; 1897 name->aname = n; 1898 name->refcnt++; 1899 1900 if (!context->pwd.dentry) 1901 get_fs_pwd(current->fs, &context->pwd); 1902 } 1903 1904 static inline int audit_copy_fcaps(struct audit_names *name, 1905 const struct dentry *dentry) 1906 { 1907 struct cpu_vfs_cap_data caps; 1908 int rc; 1909 1910 if (!dentry) 1911 return 0; 1912 1913 rc = get_vfs_caps_from_disk(dentry, &caps); 1914 if (rc) 1915 return rc; 1916 1917 name->fcap.permitted = caps.permitted; 1918 name->fcap.inheritable = caps.inheritable; 1919 name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 1920 name->fcap.rootid = caps.rootid; 1921 name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> 1922 VFS_CAP_REVISION_SHIFT; 1923 1924 return 0; 1925 } 1926 1927 /* Copy inode data into an audit_names. */ 1928 static void audit_copy_inode(struct audit_names *name, 1929 const struct dentry *dentry, 1930 struct inode *inode, unsigned int flags) 1931 { 1932 name->ino = inode->i_ino; 1933 name->dev = inode->i_sb->s_dev; 1934 name->mode = inode->i_mode; 1935 name->uid = inode->i_uid; 1936 name->gid = inode->i_gid; 1937 name->rdev = inode->i_rdev; 1938 security_inode_getsecid(inode, &name->osid); 1939 if (flags & AUDIT_INODE_NOEVAL) { 1940 name->fcap_ver = -1; 1941 return; 1942 } 1943 audit_copy_fcaps(name, dentry); 1944 } 1945 1946 /** 1947 * __audit_inode - store the inode and device from a lookup 1948 * @name: name being audited 1949 * @dentry: dentry being audited 1950 * @flags: attributes for this particular entry 1951 */ 1952 void __audit_inode(struct filename *name, const struct dentry *dentry, 1953 unsigned int flags) 1954 { 1955 struct audit_context *context = audit_context(); 1956 struct inode *inode = d_backing_inode(dentry); 1957 struct audit_names *n; 1958 bool parent = flags & AUDIT_INODE_PARENT; 1959 struct audit_entry *e; 1960 struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS]; 1961 int i; 1962 1963 if (!context->in_syscall) 1964 return; 1965 1966 rcu_read_lock(); 1967 list_for_each_entry_rcu(e, list, list) { 1968 for (i = 0; i < e->rule.field_count; i++) { 1969 struct audit_field *f = &e->rule.fields[i]; 1970 1971 if (f->type == AUDIT_FSTYPE 1972 && audit_comparator(inode->i_sb->s_magic, 1973 f->op, f->val) 1974 && e->rule.action == AUDIT_NEVER) { 1975 rcu_read_unlock(); 1976 return; 1977 } 1978 } 1979 } 1980 rcu_read_unlock(); 1981 1982 if (!name) 1983 goto out_alloc; 1984 1985 /* 1986 * If we have a pointer to an audit_names entry already, then we can 1987 * just use it directly if the type is correct. 1988 */ 1989 n = name->aname; 1990 if (n) { 1991 if (parent) { 1992 if (n->type == AUDIT_TYPE_PARENT || 1993 n->type == AUDIT_TYPE_UNKNOWN) 1994 goto out; 1995 } else { 1996 if (n->type != AUDIT_TYPE_PARENT) 1997 goto out; 1998 } 1999 } 2000 2001 list_for_each_entry_reverse(n, &context->names_list, list) { 2002 if (n->ino) { 2003 /* valid inode number, use that for the comparison */ 2004 if (n->ino != inode->i_ino || 2005 n->dev != inode->i_sb->s_dev) 2006 continue; 2007 } else if (n->name) { 2008 /* inode number has not been set, check the name */ 2009 if (strcmp(n->name->name, name->name)) 2010 continue; 2011 } else 2012 /* no inode and no name (?!) ... this is odd ... */ 2013 continue; 2014 2015 /* match the correct record type */ 2016 if (parent) { 2017 if (n->type == AUDIT_TYPE_PARENT || 2018 n->type == AUDIT_TYPE_UNKNOWN) 2019 goto out; 2020 } else { 2021 if (n->type != AUDIT_TYPE_PARENT) 2022 goto out; 2023 } 2024 } 2025 2026 out_alloc: 2027 /* unable to find an entry with both a matching name and type */ 2028 n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); 2029 if (!n) 2030 return; 2031 if (name) { 2032 n->name = name; 2033 name->refcnt++; 2034 } 2035 2036 out: 2037 if (parent) { 2038 n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL; 2039 n->type = AUDIT_TYPE_PARENT; 2040 if (flags & AUDIT_INODE_HIDDEN) 2041 n->hidden = true; 2042 } else { 2043 n->name_len = AUDIT_NAME_FULL; 2044 n->type = AUDIT_TYPE_NORMAL; 2045 } 2046 handle_path(dentry); 2047 audit_copy_inode(n, dentry, inode, flags & AUDIT_INODE_NOEVAL); 2048 } 2049 2050 void __audit_file(const struct file *file) 2051 { 2052 __audit_inode(NULL, file->f_path.dentry, 0); 2053 } 2054 2055 /** 2056 * __audit_inode_child - collect inode info for created/removed objects 2057 * @parent: inode of dentry parent 2058 * @dentry: dentry being audited 2059 * @type: AUDIT_TYPE_* value that we're looking for 2060 * 2061 * For syscalls that create or remove filesystem objects, audit_inode 2062 * can only collect information for the filesystem object's parent. 2063 * This call updates the audit context with the child's information. 2064 * Syscalls that create a new filesystem object must be hooked after 2065 * the object is created. Syscalls that remove a filesystem object 2066 * must be hooked prior, in order to capture the target inode during 2067 * unsuccessful attempts. 2068 */ 2069 void __audit_inode_child(struct inode *parent, 2070 const struct dentry *dentry, 2071 const unsigned char type) 2072 { 2073 struct audit_context *context = audit_context(); 2074 struct inode *inode = d_backing_inode(dentry); 2075 const struct qstr *dname = &dentry->d_name; 2076 struct audit_names *n, *found_parent = NULL, *found_child = NULL; 2077 struct audit_entry *e; 2078 struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS]; 2079 int i; 2080 2081 if (!context->in_syscall) 2082 return; 2083 2084 rcu_read_lock(); 2085 list_for_each_entry_rcu(e, list, list) { 2086 for (i = 0; i < e->rule.field_count; i++) { 2087 struct audit_field *f = &e->rule.fields[i]; 2088 2089 if (f->type == AUDIT_FSTYPE 2090 && audit_comparator(parent->i_sb->s_magic, 2091 f->op, f->val) 2092 && e->rule.action == AUDIT_NEVER) { 2093 rcu_read_unlock(); 2094 return; 2095 } 2096 } 2097 } 2098 rcu_read_unlock(); 2099 2100 if (inode) 2101 handle_one(inode); 2102 2103 /* look for a parent entry first */ 2104 list_for_each_entry(n, &context->names_list, list) { 2105 if (!n->name || 2106 (n->type != AUDIT_TYPE_PARENT && 2107 n->type != AUDIT_TYPE_UNKNOWN)) 2108 continue; 2109 2110 if (n->ino == parent->i_ino && n->dev == parent->i_sb->s_dev && 2111 !audit_compare_dname_path(dname, 2112 n->name->name, n->name_len)) { 2113 if (n->type == AUDIT_TYPE_UNKNOWN) 2114 n->type = AUDIT_TYPE_PARENT; 2115 found_parent = n; 2116 break; 2117 } 2118 } 2119 2120 /* is there a matching child entry? */ 2121 list_for_each_entry(n, &context->names_list, list) { 2122 /* can only match entries that have a name */ 2123 if (!n->name || 2124 (n->type != type && n->type != AUDIT_TYPE_UNKNOWN)) 2125 continue; 2126 2127 if (!strcmp(dname->name, n->name->name) || 2128 !audit_compare_dname_path(dname, n->name->name, 2129 found_parent ? 2130 found_parent->name_len : 2131 AUDIT_NAME_FULL)) { 2132 if (n->type == AUDIT_TYPE_UNKNOWN) 2133 n->type = type; 2134 found_child = n; 2135 break; 2136 } 2137 } 2138 2139 if (!found_parent) { 2140 /* create a new, "anonymous" parent record */ 2141 n = audit_alloc_name(context, AUDIT_TYPE_PARENT); 2142 if (!n) 2143 return; 2144 audit_copy_inode(n, NULL, parent, 0); 2145 } 2146 2147 if (!found_child) { 2148 found_child = audit_alloc_name(context, type); 2149 if (!found_child) 2150 return; 2151 2152 /* Re-use the name belonging to the slot for a matching parent 2153 * directory. All names for this context are relinquished in 2154 * audit_free_names() */ 2155 if (found_parent) { 2156 found_child->name = found_parent->name; 2157 found_child->name_len = AUDIT_NAME_FULL; 2158 found_child->name->refcnt++; 2159 } 2160 } 2161 2162 if (inode) 2163 audit_copy_inode(found_child, dentry, inode, 0); 2164 else 2165 found_child->ino = AUDIT_INO_UNSET; 2166 } 2167 EXPORT_SYMBOL_GPL(__audit_inode_child); 2168 2169 /** 2170 * auditsc_get_stamp - get local copies of audit_context values 2171 * @ctx: audit_context for the task 2172 * @t: timespec64 to store time recorded in the audit_context 2173 * @serial: serial value that is recorded in the audit_context 2174 * 2175 * Also sets the context as auditable. 2176 */ 2177 int auditsc_get_stamp(struct audit_context *ctx, 2178 struct timespec64 *t, unsigned int *serial) 2179 { 2180 if (!ctx->in_syscall) 2181 return 0; 2182 if (!ctx->serial) 2183 ctx->serial = audit_serial(); 2184 t->tv_sec = ctx->ctime.tv_sec; 2185 t->tv_nsec = ctx->ctime.tv_nsec; 2186 *serial = ctx->serial; 2187 if (!ctx->prio) { 2188 ctx->prio = 1; 2189 ctx->current_state = AUDIT_RECORD_CONTEXT; 2190 } 2191 return 1; 2192 } 2193 2194 /** 2195 * __audit_mq_open - record audit data for a POSIX MQ open 2196 * @oflag: open flag 2197 * @mode: mode bits 2198 * @attr: queue attributes 2199 * 2200 */ 2201 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr) 2202 { 2203 struct audit_context *context = audit_context(); 2204 2205 if (attr) 2206 memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr)); 2207 else 2208 memset(&context->mq_open.attr, 0, sizeof(struct mq_attr)); 2209 2210 context->mq_open.oflag = oflag; 2211 context->mq_open.mode = mode; 2212 2213 context->type = AUDIT_MQ_OPEN; 2214 } 2215 2216 /** 2217 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive 2218 * @mqdes: MQ descriptor 2219 * @msg_len: Message length 2220 * @msg_prio: Message priority 2221 * @abs_timeout: Message timeout in absolute time 2222 * 2223 */ 2224 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, 2225 const struct timespec64 *abs_timeout) 2226 { 2227 struct audit_context *context = audit_context(); 2228 struct timespec64 *p = &context->mq_sendrecv.abs_timeout; 2229 2230 if (abs_timeout) 2231 memcpy(p, abs_timeout, sizeof(*p)); 2232 else 2233 memset(p, 0, sizeof(*p)); 2234 2235 context->mq_sendrecv.mqdes = mqdes; 2236 context->mq_sendrecv.msg_len = msg_len; 2237 context->mq_sendrecv.msg_prio = msg_prio; 2238 2239 context->type = AUDIT_MQ_SENDRECV; 2240 } 2241 2242 /** 2243 * __audit_mq_notify - record audit data for a POSIX MQ notify 2244 * @mqdes: MQ descriptor 2245 * @notification: Notification event 2246 * 2247 */ 2248 2249 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification) 2250 { 2251 struct audit_context *context = audit_context(); 2252 2253 if (notification) 2254 context->mq_notify.sigev_signo = notification->sigev_signo; 2255 else 2256 context->mq_notify.sigev_signo = 0; 2257 2258 context->mq_notify.mqdes = mqdes; 2259 context->type = AUDIT_MQ_NOTIFY; 2260 } 2261 2262 /** 2263 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute 2264 * @mqdes: MQ descriptor 2265 * @mqstat: MQ flags 2266 * 2267 */ 2268 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) 2269 { 2270 struct audit_context *context = audit_context(); 2271 context->mq_getsetattr.mqdes = mqdes; 2272 context->mq_getsetattr.mqstat = *mqstat; 2273 context->type = AUDIT_MQ_GETSETATTR; 2274 } 2275 2276 /** 2277 * __audit_ipc_obj - record audit data for ipc object 2278 * @ipcp: ipc permissions 2279 * 2280 */ 2281 void __audit_ipc_obj(struct kern_ipc_perm *ipcp) 2282 { 2283 struct audit_context *context = audit_context(); 2284 context->ipc.uid = ipcp->uid; 2285 context->ipc.gid = ipcp->gid; 2286 context->ipc.mode = ipcp->mode; 2287 context->ipc.has_perm = 0; 2288 security_ipc_getsecid(ipcp, &context->ipc.osid); 2289 context->type = AUDIT_IPC; 2290 } 2291 2292 /** 2293 * __audit_ipc_set_perm - record audit data for new ipc permissions 2294 * @qbytes: msgq bytes 2295 * @uid: msgq user id 2296 * @gid: msgq group id 2297 * @mode: msgq mode (permissions) 2298 * 2299 * Called only after audit_ipc_obj(). 2300 */ 2301 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode) 2302 { 2303 struct audit_context *context = audit_context(); 2304 2305 context->ipc.qbytes = qbytes; 2306 context->ipc.perm_uid = uid; 2307 context->ipc.perm_gid = gid; 2308 context->ipc.perm_mode = mode; 2309 context->ipc.has_perm = 1; 2310 } 2311 2312 void __audit_bprm(struct linux_binprm *bprm) 2313 { 2314 struct audit_context *context = audit_context(); 2315 2316 context->type = AUDIT_EXECVE; 2317 context->execve.argc = bprm->argc; 2318 } 2319 2320 2321 /** 2322 * __audit_socketcall - record audit data for sys_socketcall 2323 * @nargs: number of args, which should not be more than AUDITSC_ARGS. 2324 * @args: args array 2325 * 2326 */ 2327 int __audit_socketcall(int nargs, unsigned long *args) 2328 { 2329 struct audit_context *context = audit_context(); 2330 2331 if (nargs <= 0 || nargs > AUDITSC_ARGS || !args) 2332 return -EINVAL; 2333 context->type = AUDIT_SOCKETCALL; 2334 context->socketcall.nargs = nargs; 2335 memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long)); 2336 return 0; 2337 } 2338 2339 /** 2340 * __audit_fd_pair - record audit data for pipe and socketpair 2341 * @fd1: the first file descriptor 2342 * @fd2: the second file descriptor 2343 * 2344 */ 2345 void __audit_fd_pair(int fd1, int fd2) 2346 { 2347 struct audit_context *context = audit_context(); 2348 context->fds[0] = fd1; 2349 context->fds[1] = fd2; 2350 } 2351 2352 /** 2353 * __audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto 2354 * @len: data length in user space 2355 * @a: data address in kernel space 2356 * 2357 * Returns 0 for success or NULL context or < 0 on error. 2358 */ 2359 int __audit_sockaddr(int len, void *a) 2360 { 2361 struct audit_context *context = audit_context(); 2362 2363 if (!context->sockaddr) { 2364 void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL); 2365 if (!p) 2366 return -ENOMEM; 2367 context->sockaddr = p; 2368 } 2369 2370 context->sockaddr_len = len; 2371 memcpy(context->sockaddr, a, len); 2372 return 0; 2373 } 2374 2375 void __audit_ptrace(struct task_struct *t) 2376 { 2377 struct audit_context *context = audit_context(); 2378 2379 context->target_pid = task_tgid_nr(t); 2380 context->target_auid = audit_get_loginuid(t); 2381 context->target_uid = task_uid(t); 2382 context->target_sessionid = audit_get_sessionid(t); 2383 security_task_getsecid(t, &context->target_sid); 2384 memcpy(context->target_comm, t->comm, TASK_COMM_LEN); 2385 } 2386 2387 /** 2388 * audit_signal_info_syscall - record signal info for syscalls 2389 * @t: task being signaled 2390 * 2391 * If the audit subsystem is being terminated, record the task (pid) 2392 * and uid that is doing that. 2393 */ 2394 int audit_signal_info_syscall(struct task_struct *t) 2395 { 2396 struct audit_aux_data_pids *axp; 2397 struct audit_context *ctx = audit_context(); 2398 kuid_t t_uid = task_uid(t); 2399 2400 if (!audit_signals || audit_dummy_context()) 2401 return 0; 2402 2403 /* optimize the common case by putting first signal recipient directly 2404 * in audit_context */ 2405 if (!ctx->target_pid) { 2406 ctx->target_pid = task_tgid_nr(t); 2407 ctx->target_auid = audit_get_loginuid(t); 2408 ctx->target_uid = t_uid; 2409 ctx->target_sessionid = audit_get_sessionid(t); 2410 security_task_getsecid(t, &ctx->target_sid); 2411 memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); 2412 return 0; 2413 } 2414 2415 axp = (void *)ctx->aux_pids; 2416 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { 2417 axp = kzalloc(sizeof(*axp), GFP_ATOMIC); 2418 if (!axp) 2419 return -ENOMEM; 2420 2421 axp->d.type = AUDIT_OBJ_PID; 2422 axp->d.next = ctx->aux_pids; 2423 ctx->aux_pids = (void *)axp; 2424 } 2425 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); 2426 2427 axp->target_pid[axp->pid_count] = task_tgid_nr(t); 2428 axp->target_auid[axp->pid_count] = audit_get_loginuid(t); 2429 axp->target_uid[axp->pid_count] = t_uid; 2430 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); 2431 security_task_getsecid(t, &axp->target_sid[axp->pid_count]); 2432 memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); 2433 axp->pid_count++; 2434 2435 return 0; 2436 } 2437 2438 /** 2439 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps 2440 * @bprm: pointer to the bprm being processed 2441 * @new: the proposed new credentials 2442 * @old: the old credentials 2443 * 2444 * Simply check if the proc already has the caps given by the file and if not 2445 * store the priv escalation info for later auditing at the end of the syscall 2446 * 2447 * -Eric 2448 */ 2449 int __audit_log_bprm_fcaps(struct linux_binprm *bprm, 2450 const struct cred *new, const struct cred *old) 2451 { 2452 struct audit_aux_data_bprm_fcaps *ax; 2453 struct audit_context *context = audit_context(); 2454 struct cpu_vfs_cap_data vcaps; 2455 2456 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2457 if (!ax) 2458 return -ENOMEM; 2459 2460 ax->d.type = AUDIT_BPRM_FCAPS; 2461 ax->d.next = context->aux; 2462 context->aux = (void *)ax; 2463 2464 get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps); 2465 2466 ax->fcap.permitted = vcaps.permitted; 2467 ax->fcap.inheritable = vcaps.inheritable; 2468 ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 2469 ax->fcap.rootid = vcaps.rootid; 2470 ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; 2471 2472 ax->old_pcap.permitted = old->cap_permitted; 2473 ax->old_pcap.inheritable = old->cap_inheritable; 2474 ax->old_pcap.effective = old->cap_effective; 2475 ax->old_pcap.ambient = old->cap_ambient; 2476 2477 ax->new_pcap.permitted = new->cap_permitted; 2478 ax->new_pcap.inheritable = new->cap_inheritable; 2479 ax->new_pcap.effective = new->cap_effective; 2480 ax->new_pcap.ambient = new->cap_ambient; 2481 return 0; 2482 } 2483 2484 /** 2485 * __audit_log_capset - store information about the arguments to the capset syscall 2486 * @new: the new credentials 2487 * @old: the old (current) credentials 2488 * 2489 * Record the arguments userspace sent to sys_capset for later printing by the 2490 * audit system if applicable 2491 */ 2492 void __audit_log_capset(const struct cred *new, const struct cred *old) 2493 { 2494 struct audit_context *context = audit_context(); 2495 context->capset.pid = task_tgid_nr(current); 2496 context->capset.cap.effective = new->cap_effective; 2497 context->capset.cap.inheritable = new->cap_effective; 2498 context->capset.cap.permitted = new->cap_permitted; 2499 context->capset.cap.ambient = new->cap_ambient; 2500 context->type = AUDIT_CAPSET; 2501 } 2502 2503 void __audit_mmap_fd(int fd, int flags) 2504 { 2505 struct audit_context *context = audit_context(); 2506 context->mmap.fd = fd; 2507 context->mmap.flags = flags; 2508 context->type = AUDIT_MMAP; 2509 } 2510 2511 void __audit_log_kern_module(char *name) 2512 { 2513 struct audit_context *context = audit_context(); 2514 2515 context->module.name = kstrdup(name, GFP_KERNEL); 2516 if (!context->module.name) 2517 audit_log_lost("out of memory in __audit_log_kern_module"); 2518 context->type = AUDIT_KERN_MODULE; 2519 } 2520 2521 void __audit_fanotify(unsigned int response) 2522 { 2523 audit_log(audit_context(), GFP_KERNEL, 2524 AUDIT_FANOTIFY, "resp=%u", response); 2525 } 2526 2527 void __audit_tk_injoffset(struct timespec64 offset) 2528 { 2529 audit_log(audit_context(), GFP_KERNEL, AUDIT_TIME_INJOFFSET, 2530 "sec=%lli nsec=%li", 2531 (long long)offset.tv_sec, offset.tv_nsec); 2532 } 2533 2534 static void audit_log_ntp_val(const struct audit_ntp_data *ad, 2535 const char *op, enum audit_ntp_type type) 2536 { 2537 const struct audit_ntp_val *val = &ad->vals[type]; 2538 2539 if (val->newval == val->oldval) 2540 return; 2541 2542 audit_log(audit_context(), GFP_KERNEL, AUDIT_TIME_ADJNTPVAL, 2543 "op=%s old=%lli new=%lli", op, val->oldval, val->newval); 2544 } 2545 2546 void __audit_ntp_log(const struct audit_ntp_data *ad) 2547 { 2548 audit_log_ntp_val(ad, "offset", AUDIT_NTP_OFFSET); 2549 audit_log_ntp_val(ad, "freq", AUDIT_NTP_FREQ); 2550 audit_log_ntp_val(ad, "status", AUDIT_NTP_STATUS); 2551 audit_log_ntp_val(ad, "tai", AUDIT_NTP_TAI); 2552 audit_log_ntp_val(ad, "tick", AUDIT_NTP_TICK); 2553 audit_log_ntp_val(ad, "adjust", AUDIT_NTP_ADJUST); 2554 } 2555 2556 void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries, 2557 enum audit_nfcfgop op) 2558 { 2559 struct audit_buffer *ab; 2560 char comm[sizeof(current->comm)]; 2561 2562 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_NETFILTER_CFG); 2563 if (!ab) 2564 return; 2565 audit_log_format(ab, "table=%s family=%u entries=%u op=%s", 2566 name, af, nentries, audit_nfcfgs[op].s); 2567 2568 audit_log_format(ab, " pid=%u", task_pid_nr(current)); 2569 audit_log_task_context(ab); /* subj= */ 2570 audit_log_format(ab, " comm="); 2571 audit_log_untrustedstring(ab, get_task_comm(comm, current)); 2572 audit_log_end(ab); 2573 } 2574 EXPORT_SYMBOL_GPL(__audit_log_nfcfg); 2575 2576 static void audit_log_task(struct audit_buffer *ab) 2577 { 2578 kuid_t auid, uid; 2579 kgid_t gid; 2580 unsigned int sessionid; 2581 char comm[sizeof(current->comm)]; 2582 2583 auid = audit_get_loginuid(current); 2584 sessionid = audit_get_sessionid(current); 2585 current_uid_gid(&uid, &gid); 2586 2587 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", 2588 from_kuid(&init_user_ns, auid), 2589 from_kuid(&init_user_ns, uid), 2590 from_kgid(&init_user_ns, gid), 2591 sessionid); 2592 audit_log_task_context(ab); 2593 audit_log_format(ab, " pid=%d comm=", task_tgid_nr(current)); 2594 audit_log_untrustedstring(ab, get_task_comm(comm, current)); 2595 audit_log_d_path_exe(ab, current->mm); 2596 } 2597 2598 /** 2599 * audit_core_dumps - record information about processes that end abnormally 2600 * @signr: signal value 2601 * 2602 * If a process ends with a core dump, something fishy is going on and we 2603 * should record the event for investigation. 2604 */ 2605 void audit_core_dumps(long signr) 2606 { 2607 struct audit_buffer *ab; 2608 2609 if (!audit_enabled) 2610 return; 2611 2612 if (signr == SIGQUIT) /* don't care for those */ 2613 return; 2614 2615 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_ANOM_ABEND); 2616 if (unlikely(!ab)) 2617 return; 2618 audit_log_task(ab); 2619 audit_log_format(ab, " sig=%ld res=1", signr); 2620 audit_log_end(ab); 2621 } 2622 2623 /** 2624 * audit_seccomp - record information about a seccomp action 2625 * @syscall: syscall number 2626 * @signr: signal value 2627 * @code: the seccomp action 2628 * 2629 * Record the information associated with a seccomp action. Event filtering for 2630 * seccomp actions that are not to be logged is done in seccomp_log(). 2631 * Therefore, this function forces auditing independent of the audit_enabled 2632 * and dummy context state because seccomp actions should be logged even when 2633 * audit is not in use. 2634 */ 2635 void audit_seccomp(unsigned long syscall, long signr, int code) 2636 { 2637 struct audit_buffer *ab; 2638 2639 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_SECCOMP); 2640 if (unlikely(!ab)) 2641 return; 2642 audit_log_task(ab); 2643 audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x", 2644 signr, syscall_get_arch(current), syscall, 2645 in_compat_syscall(), KSTK_EIP(current), code); 2646 audit_log_end(ab); 2647 } 2648 2649 void audit_seccomp_actions_logged(const char *names, const char *old_names, 2650 int res) 2651 { 2652 struct audit_buffer *ab; 2653 2654 if (!audit_enabled) 2655 return; 2656 2657 ab = audit_log_start(audit_context(), GFP_KERNEL, 2658 AUDIT_CONFIG_CHANGE); 2659 if (unlikely(!ab)) 2660 return; 2661 2662 audit_log_format(ab, 2663 "op=seccomp-logging actions=%s old-actions=%s res=%d", 2664 names, old_names, res); 2665 audit_log_end(ab); 2666 } 2667 2668 struct list_head *audit_killed_trees(void) 2669 { 2670 struct audit_context *ctx = audit_context(); 2671 if (likely(!ctx || !ctx->in_syscall)) 2672 return NULL; 2673 return &ctx->killed_trees; 2674 } 2675