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 if (!context || context->dummy) 1421 return; 1422 1423 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE); 1424 if (!ab) 1425 return; /* audit_panic or being filtered */ 1426 1427 audit_log_format(ab, "proctitle="); 1428 1429 /* Not cached */ 1430 if (!context->proctitle.value) { 1431 buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL); 1432 if (!buf) 1433 goto out; 1434 /* Historically called this from procfs naming */ 1435 res = get_cmdline(current, buf, MAX_PROCTITLE_AUDIT_LEN); 1436 if (res == 0) { 1437 kfree(buf); 1438 goto out; 1439 } 1440 res = audit_proctitle_rtrim(buf, res); 1441 if (res == 0) { 1442 kfree(buf); 1443 goto out; 1444 } 1445 context->proctitle.value = buf; 1446 context->proctitle.len = res; 1447 } 1448 msg = context->proctitle.value; 1449 len = context->proctitle.len; 1450 out: 1451 audit_log_n_untrustedstring(ab, msg, len); 1452 audit_log_end(ab); 1453 } 1454 1455 static void audit_log_exit(void) 1456 { 1457 int i, call_panic = 0; 1458 struct audit_context *context = audit_context(); 1459 struct audit_buffer *ab; 1460 struct audit_aux_data *aux; 1461 struct audit_names *n; 1462 1463 context->personality = current->personality; 1464 1465 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); 1466 if (!ab) 1467 return; /* audit_panic has been called */ 1468 audit_log_format(ab, "arch=%x syscall=%d", 1469 context->arch, context->major); 1470 if (context->personality != PER_LINUX) 1471 audit_log_format(ab, " per=%lx", context->personality); 1472 if (context->return_valid) 1473 audit_log_format(ab, " success=%s exit=%ld", 1474 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", 1475 context->return_code); 1476 1477 audit_log_format(ab, 1478 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d", 1479 context->argv[0], 1480 context->argv[1], 1481 context->argv[2], 1482 context->argv[3], 1483 context->name_count); 1484 1485 audit_log_task_info(ab); 1486 audit_log_key(ab, context->filterkey); 1487 audit_log_end(ab); 1488 1489 for (aux = context->aux; aux; aux = aux->next) { 1490 1491 ab = audit_log_start(context, GFP_KERNEL, aux->type); 1492 if (!ab) 1493 continue; /* audit_panic has been called */ 1494 1495 switch (aux->type) { 1496 1497 case AUDIT_BPRM_FCAPS: { 1498 struct audit_aux_data_bprm_fcaps *axs = (void *)aux; 1499 audit_log_format(ab, "fver=%x", axs->fcap_ver); 1500 audit_log_cap(ab, "fp", &axs->fcap.permitted); 1501 audit_log_cap(ab, "fi", &axs->fcap.inheritable); 1502 audit_log_format(ab, " fe=%d", axs->fcap.fE); 1503 audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted); 1504 audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable); 1505 audit_log_cap(ab, "old_pe", &axs->old_pcap.effective); 1506 audit_log_cap(ab, "old_pa", &axs->old_pcap.ambient); 1507 audit_log_cap(ab, "pp", &axs->new_pcap.permitted); 1508 audit_log_cap(ab, "pi", &axs->new_pcap.inheritable); 1509 audit_log_cap(ab, "pe", &axs->new_pcap.effective); 1510 audit_log_cap(ab, "pa", &axs->new_pcap.ambient); 1511 audit_log_format(ab, " frootid=%d", 1512 from_kuid(&init_user_ns, 1513 axs->fcap.rootid)); 1514 break; } 1515 1516 } 1517 audit_log_end(ab); 1518 } 1519 1520 if (context->type) 1521 show_special(context, &call_panic); 1522 1523 if (context->fds[0] >= 0) { 1524 ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR); 1525 if (ab) { 1526 audit_log_format(ab, "fd0=%d fd1=%d", 1527 context->fds[0], context->fds[1]); 1528 audit_log_end(ab); 1529 } 1530 } 1531 1532 if (context->sockaddr_len) { 1533 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR); 1534 if (ab) { 1535 audit_log_format(ab, "saddr="); 1536 audit_log_n_hex(ab, (void *)context->sockaddr, 1537 context->sockaddr_len); 1538 audit_log_end(ab); 1539 } 1540 } 1541 1542 for (aux = context->aux_pids; aux; aux = aux->next) { 1543 struct audit_aux_data_pids *axs = (void *)aux; 1544 1545 for (i = 0; i < axs->pid_count; i++) 1546 if (audit_log_pid_context(context, axs->target_pid[i], 1547 axs->target_auid[i], 1548 axs->target_uid[i], 1549 axs->target_sessionid[i], 1550 axs->target_sid[i], 1551 axs->target_comm[i])) 1552 call_panic = 1; 1553 } 1554 1555 if (context->target_pid && 1556 audit_log_pid_context(context, context->target_pid, 1557 context->target_auid, context->target_uid, 1558 context->target_sessionid, 1559 context->target_sid, context->target_comm)) 1560 call_panic = 1; 1561 1562 if (context->pwd.dentry && context->pwd.mnt) { 1563 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); 1564 if (ab) { 1565 audit_log_d_path(ab, "cwd=", &context->pwd); 1566 audit_log_end(ab); 1567 } 1568 } 1569 1570 i = 0; 1571 list_for_each_entry(n, &context->names_list, list) { 1572 if (n->hidden) 1573 continue; 1574 audit_log_name(context, n, NULL, i++, &call_panic); 1575 } 1576 1577 audit_log_proctitle(); 1578 1579 /* Send end of event record to help user space know we are finished */ 1580 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); 1581 if (ab) 1582 audit_log_end(ab); 1583 if (call_panic) 1584 audit_panic("error converting sid to string"); 1585 } 1586 1587 /** 1588 * __audit_free - free a per-task audit context 1589 * @tsk: task whose audit context block to free 1590 * 1591 * Called from copy_process and do_exit 1592 */ 1593 void __audit_free(struct task_struct *tsk) 1594 { 1595 struct audit_context *context = tsk->audit_context; 1596 1597 if (!context) 1598 return; 1599 1600 if (!list_empty(&context->killed_trees)) 1601 audit_kill_trees(context); 1602 1603 /* We are called either by do_exit() or the fork() error handling code; 1604 * in the former case tsk == current and in the latter tsk is a 1605 * random task_struct that doesn't doesn't have any meaningful data we 1606 * need to log via audit_log_exit(). 1607 */ 1608 if (tsk == current && !context->dummy && context->in_syscall) { 1609 context->return_valid = 0; 1610 context->return_code = 0; 1611 1612 audit_filter_syscall(tsk, context, 1613 &audit_filter_list[AUDIT_FILTER_EXIT]); 1614 audit_filter_inodes(tsk, context); 1615 if (context->current_state == AUDIT_RECORD_CONTEXT) 1616 audit_log_exit(); 1617 } 1618 1619 audit_set_context(tsk, NULL); 1620 audit_free_context(context); 1621 } 1622 1623 /** 1624 * __audit_syscall_entry - fill in an audit record at syscall entry 1625 * @major: major syscall type (function) 1626 * @a1: additional syscall register 1 1627 * @a2: additional syscall register 2 1628 * @a3: additional syscall register 3 1629 * @a4: additional syscall register 4 1630 * 1631 * Fill in audit context at syscall entry. This only happens if the 1632 * audit context was created when the task was created and the state or 1633 * filters demand the audit context be built. If the state from the 1634 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, 1635 * then the record will be written at syscall exit time (otherwise, it 1636 * will only be written if another part of the kernel requests that it 1637 * be written). 1638 */ 1639 void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2, 1640 unsigned long a3, unsigned long a4) 1641 { 1642 struct audit_context *context = audit_context(); 1643 enum audit_state state; 1644 1645 if (!audit_enabled || !context) 1646 return; 1647 1648 BUG_ON(context->in_syscall || context->name_count); 1649 1650 state = context->state; 1651 if (state == AUDIT_DISABLED) 1652 return; 1653 1654 context->dummy = !audit_n_rules; 1655 if (!context->dummy && state == AUDIT_BUILD_CONTEXT) { 1656 context->prio = 0; 1657 if (auditd_test_task(current)) 1658 return; 1659 } 1660 1661 context->arch = syscall_get_arch(current); 1662 context->major = major; 1663 context->argv[0] = a1; 1664 context->argv[1] = a2; 1665 context->argv[2] = a3; 1666 context->argv[3] = a4; 1667 context->serial = 0; 1668 context->in_syscall = 1; 1669 context->current_state = state; 1670 context->ppid = 0; 1671 ktime_get_coarse_real_ts64(&context->ctime); 1672 } 1673 1674 /** 1675 * __audit_syscall_exit - deallocate audit context after a system call 1676 * @success: success value of the syscall 1677 * @return_code: return value of the syscall 1678 * 1679 * Tear down after system call. If the audit context has been marked as 1680 * auditable (either because of the AUDIT_RECORD_CONTEXT state from 1681 * filtering, or because some other part of the kernel wrote an audit 1682 * message), then write out the syscall information. In call cases, 1683 * free the names stored from getname(). 1684 */ 1685 void __audit_syscall_exit(int success, long return_code) 1686 { 1687 struct audit_context *context; 1688 1689 context = audit_context(); 1690 if (!context) 1691 return; 1692 1693 if (!list_empty(&context->killed_trees)) 1694 audit_kill_trees(context); 1695 1696 if (!context->dummy && context->in_syscall) { 1697 if (success) 1698 context->return_valid = AUDITSC_SUCCESS; 1699 else 1700 context->return_valid = AUDITSC_FAILURE; 1701 1702 /* 1703 * we need to fix up the return code in the audit logs if the 1704 * actual return codes are later going to be fixed up by the 1705 * arch specific signal handlers 1706 * 1707 * This is actually a test for: 1708 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) || 1709 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK) 1710 * 1711 * but is faster than a bunch of || 1712 */ 1713 if (unlikely(return_code <= -ERESTARTSYS) && 1714 (return_code >= -ERESTART_RESTARTBLOCK) && 1715 (return_code != -ENOIOCTLCMD)) 1716 context->return_code = -EINTR; 1717 else 1718 context->return_code = return_code; 1719 1720 audit_filter_syscall(current, context, 1721 &audit_filter_list[AUDIT_FILTER_EXIT]); 1722 audit_filter_inodes(current, context); 1723 if (context->current_state == AUDIT_RECORD_CONTEXT) 1724 audit_log_exit(); 1725 } 1726 1727 context->in_syscall = 0; 1728 context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 1729 1730 audit_free_module(context); 1731 audit_free_names(context); 1732 unroll_tree_refs(context, NULL, 0); 1733 audit_free_aux(context); 1734 context->aux = NULL; 1735 context->aux_pids = NULL; 1736 context->target_pid = 0; 1737 context->target_sid = 0; 1738 context->sockaddr_len = 0; 1739 context->type = 0; 1740 context->fds[0] = -1; 1741 if (context->state != AUDIT_RECORD_CONTEXT) { 1742 kfree(context->filterkey); 1743 context->filterkey = NULL; 1744 } 1745 } 1746 1747 static inline void handle_one(const struct inode *inode) 1748 { 1749 struct audit_context *context; 1750 struct audit_tree_refs *p; 1751 struct audit_chunk *chunk; 1752 int count; 1753 if (likely(!inode->i_fsnotify_marks)) 1754 return; 1755 context = audit_context(); 1756 p = context->trees; 1757 count = context->tree_count; 1758 rcu_read_lock(); 1759 chunk = audit_tree_lookup(inode); 1760 rcu_read_unlock(); 1761 if (!chunk) 1762 return; 1763 if (likely(put_tree_ref(context, chunk))) 1764 return; 1765 if (unlikely(!grow_tree_refs(context))) { 1766 pr_warn("out of memory, audit has lost a tree reference\n"); 1767 audit_set_auditable(context); 1768 audit_put_chunk(chunk); 1769 unroll_tree_refs(context, p, count); 1770 return; 1771 } 1772 put_tree_ref(context, chunk); 1773 } 1774 1775 static void handle_path(const struct dentry *dentry) 1776 { 1777 struct audit_context *context; 1778 struct audit_tree_refs *p; 1779 const struct dentry *d, *parent; 1780 struct audit_chunk *drop; 1781 unsigned long seq; 1782 int count; 1783 1784 context = audit_context(); 1785 p = context->trees; 1786 count = context->tree_count; 1787 retry: 1788 drop = NULL; 1789 d = dentry; 1790 rcu_read_lock(); 1791 seq = read_seqbegin(&rename_lock); 1792 for(;;) { 1793 struct inode *inode = d_backing_inode(d); 1794 if (inode && unlikely(inode->i_fsnotify_marks)) { 1795 struct audit_chunk *chunk; 1796 chunk = audit_tree_lookup(inode); 1797 if (chunk) { 1798 if (unlikely(!put_tree_ref(context, chunk))) { 1799 drop = chunk; 1800 break; 1801 } 1802 } 1803 } 1804 parent = d->d_parent; 1805 if (parent == d) 1806 break; 1807 d = parent; 1808 } 1809 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */ 1810 rcu_read_unlock(); 1811 if (!drop) { 1812 /* just a race with rename */ 1813 unroll_tree_refs(context, p, count); 1814 goto retry; 1815 } 1816 audit_put_chunk(drop); 1817 if (grow_tree_refs(context)) { 1818 /* OK, got more space */ 1819 unroll_tree_refs(context, p, count); 1820 goto retry; 1821 } 1822 /* too bad */ 1823 pr_warn("out of memory, audit has lost a tree reference\n"); 1824 unroll_tree_refs(context, p, count); 1825 audit_set_auditable(context); 1826 return; 1827 } 1828 rcu_read_unlock(); 1829 } 1830 1831 static struct audit_names *audit_alloc_name(struct audit_context *context, 1832 unsigned char type) 1833 { 1834 struct audit_names *aname; 1835 1836 if (context->name_count < AUDIT_NAMES) { 1837 aname = &context->preallocated_names[context->name_count]; 1838 memset(aname, 0, sizeof(*aname)); 1839 } else { 1840 aname = kzalloc(sizeof(*aname), GFP_NOFS); 1841 if (!aname) 1842 return NULL; 1843 aname->should_free = true; 1844 } 1845 1846 aname->ino = AUDIT_INO_UNSET; 1847 aname->type = type; 1848 list_add_tail(&aname->list, &context->names_list); 1849 1850 context->name_count++; 1851 return aname; 1852 } 1853 1854 /** 1855 * __audit_reusename - fill out filename with info from existing entry 1856 * @uptr: userland ptr to pathname 1857 * 1858 * Search the audit_names list for the current audit context. If there is an 1859 * existing entry with a matching "uptr" then return the filename 1860 * associated with that audit_name. If not, return NULL. 1861 */ 1862 struct filename * 1863 __audit_reusename(const __user char *uptr) 1864 { 1865 struct audit_context *context = audit_context(); 1866 struct audit_names *n; 1867 1868 list_for_each_entry(n, &context->names_list, list) { 1869 if (!n->name) 1870 continue; 1871 if (n->name->uptr == uptr) { 1872 n->name->refcnt++; 1873 return n->name; 1874 } 1875 } 1876 return NULL; 1877 } 1878 1879 /** 1880 * __audit_getname - add a name to the list 1881 * @name: name to add 1882 * 1883 * Add a name to the list of audit names for this context. 1884 * Called from fs/namei.c:getname(). 1885 */ 1886 void __audit_getname(struct filename *name) 1887 { 1888 struct audit_context *context = audit_context(); 1889 struct audit_names *n; 1890 1891 if (!context->in_syscall) 1892 return; 1893 1894 n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); 1895 if (!n) 1896 return; 1897 1898 n->name = name; 1899 n->name_len = AUDIT_NAME_FULL; 1900 name->aname = n; 1901 name->refcnt++; 1902 1903 if (!context->pwd.dentry) 1904 get_fs_pwd(current->fs, &context->pwd); 1905 } 1906 1907 static inline int audit_copy_fcaps(struct audit_names *name, 1908 const struct dentry *dentry) 1909 { 1910 struct cpu_vfs_cap_data caps; 1911 int rc; 1912 1913 if (!dentry) 1914 return 0; 1915 1916 rc = get_vfs_caps_from_disk(dentry, &caps); 1917 if (rc) 1918 return rc; 1919 1920 name->fcap.permitted = caps.permitted; 1921 name->fcap.inheritable = caps.inheritable; 1922 name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 1923 name->fcap.rootid = caps.rootid; 1924 name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> 1925 VFS_CAP_REVISION_SHIFT; 1926 1927 return 0; 1928 } 1929 1930 /* Copy inode data into an audit_names. */ 1931 static void audit_copy_inode(struct audit_names *name, 1932 const struct dentry *dentry, 1933 struct inode *inode, unsigned int flags) 1934 { 1935 name->ino = inode->i_ino; 1936 name->dev = inode->i_sb->s_dev; 1937 name->mode = inode->i_mode; 1938 name->uid = inode->i_uid; 1939 name->gid = inode->i_gid; 1940 name->rdev = inode->i_rdev; 1941 security_inode_getsecid(inode, &name->osid); 1942 if (flags & AUDIT_INODE_NOEVAL) { 1943 name->fcap_ver = -1; 1944 return; 1945 } 1946 audit_copy_fcaps(name, dentry); 1947 } 1948 1949 /** 1950 * __audit_inode - store the inode and device from a lookup 1951 * @name: name being audited 1952 * @dentry: dentry being audited 1953 * @flags: attributes for this particular entry 1954 */ 1955 void __audit_inode(struct filename *name, const struct dentry *dentry, 1956 unsigned int flags) 1957 { 1958 struct audit_context *context = audit_context(); 1959 struct inode *inode = d_backing_inode(dentry); 1960 struct audit_names *n; 1961 bool parent = flags & AUDIT_INODE_PARENT; 1962 struct audit_entry *e; 1963 struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS]; 1964 int i; 1965 1966 if (!context->in_syscall) 1967 return; 1968 1969 rcu_read_lock(); 1970 list_for_each_entry_rcu(e, list, list) { 1971 for (i = 0; i < e->rule.field_count; i++) { 1972 struct audit_field *f = &e->rule.fields[i]; 1973 1974 if (f->type == AUDIT_FSTYPE 1975 && audit_comparator(inode->i_sb->s_magic, 1976 f->op, f->val) 1977 && e->rule.action == AUDIT_NEVER) { 1978 rcu_read_unlock(); 1979 return; 1980 } 1981 } 1982 } 1983 rcu_read_unlock(); 1984 1985 if (!name) 1986 goto out_alloc; 1987 1988 /* 1989 * If we have a pointer to an audit_names entry already, then we can 1990 * just use it directly if the type is correct. 1991 */ 1992 n = name->aname; 1993 if (n) { 1994 if (parent) { 1995 if (n->type == AUDIT_TYPE_PARENT || 1996 n->type == AUDIT_TYPE_UNKNOWN) 1997 goto out; 1998 } else { 1999 if (n->type != AUDIT_TYPE_PARENT) 2000 goto out; 2001 } 2002 } 2003 2004 list_for_each_entry_reverse(n, &context->names_list, list) { 2005 if (n->ino) { 2006 /* valid inode number, use that for the comparison */ 2007 if (n->ino != inode->i_ino || 2008 n->dev != inode->i_sb->s_dev) 2009 continue; 2010 } else if (n->name) { 2011 /* inode number has not been set, check the name */ 2012 if (strcmp(n->name->name, name->name)) 2013 continue; 2014 } else 2015 /* no inode and no name (?!) ... this is odd ... */ 2016 continue; 2017 2018 /* match the correct record type */ 2019 if (parent) { 2020 if (n->type == AUDIT_TYPE_PARENT || 2021 n->type == AUDIT_TYPE_UNKNOWN) 2022 goto out; 2023 } else { 2024 if (n->type != AUDIT_TYPE_PARENT) 2025 goto out; 2026 } 2027 } 2028 2029 out_alloc: 2030 /* unable to find an entry with both a matching name and type */ 2031 n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); 2032 if (!n) 2033 return; 2034 if (name) { 2035 n->name = name; 2036 name->refcnt++; 2037 } 2038 2039 out: 2040 if (parent) { 2041 n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL; 2042 n->type = AUDIT_TYPE_PARENT; 2043 if (flags & AUDIT_INODE_HIDDEN) 2044 n->hidden = true; 2045 } else { 2046 n->name_len = AUDIT_NAME_FULL; 2047 n->type = AUDIT_TYPE_NORMAL; 2048 } 2049 handle_path(dentry); 2050 audit_copy_inode(n, dentry, inode, flags & AUDIT_INODE_NOEVAL); 2051 } 2052 2053 void __audit_file(const struct file *file) 2054 { 2055 __audit_inode(NULL, file->f_path.dentry, 0); 2056 } 2057 2058 /** 2059 * __audit_inode_child - collect inode info for created/removed objects 2060 * @parent: inode of dentry parent 2061 * @dentry: dentry being audited 2062 * @type: AUDIT_TYPE_* value that we're looking for 2063 * 2064 * For syscalls that create or remove filesystem objects, audit_inode 2065 * can only collect information for the filesystem object's parent. 2066 * This call updates the audit context with the child's information. 2067 * Syscalls that create a new filesystem object must be hooked after 2068 * the object is created. Syscalls that remove a filesystem object 2069 * must be hooked prior, in order to capture the target inode during 2070 * unsuccessful attempts. 2071 */ 2072 void __audit_inode_child(struct inode *parent, 2073 const struct dentry *dentry, 2074 const unsigned char type) 2075 { 2076 struct audit_context *context = audit_context(); 2077 struct inode *inode = d_backing_inode(dentry); 2078 const struct qstr *dname = &dentry->d_name; 2079 struct audit_names *n, *found_parent = NULL, *found_child = NULL; 2080 struct audit_entry *e; 2081 struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS]; 2082 int i; 2083 2084 if (!context->in_syscall) 2085 return; 2086 2087 rcu_read_lock(); 2088 list_for_each_entry_rcu(e, list, list) { 2089 for (i = 0; i < e->rule.field_count; i++) { 2090 struct audit_field *f = &e->rule.fields[i]; 2091 2092 if (f->type == AUDIT_FSTYPE 2093 && audit_comparator(parent->i_sb->s_magic, 2094 f->op, f->val) 2095 && e->rule.action == AUDIT_NEVER) { 2096 rcu_read_unlock(); 2097 return; 2098 } 2099 } 2100 } 2101 rcu_read_unlock(); 2102 2103 if (inode) 2104 handle_one(inode); 2105 2106 /* look for a parent entry first */ 2107 list_for_each_entry(n, &context->names_list, list) { 2108 if (!n->name || 2109 (n->type != AUDIT_TYPE_PARENT && 2110 n->type != AUDIT_TYPE_UNKNOWN)) 2111 continue; 2112 2113 if (n->ino == parent->i_ino && n->dev == parent->i_sb->s_dev && 2114 !audit_compare_dname_path(dname, 2115 n->name->name, n->name_len)) { 2116 if (n->type == AUDIT_TYPE_UNKNOWN) 2117 n->type = AUDIT_TYPE_PARENT; 2118 found_parent = n; 2119 break; 2120 } 2121 } 2122 2123 /* is there a matching child entry? */ 2124 list_for_each_entry(n, &context->names_list, list) { 2125 /* can only match entries that have a name */ 2126 if (!n->name || 2127 (n->type != type && n->type != AUDIT_TYPE_UNKNOWN)) 2128 continue; 2129 2130 if (!strcmp(dname->name, n->name->name) || 2131 !audit_compare_dname_path(dname, n->name->name, 2132 found_parent ? 2133 found_parent->name_len : 2134 AUDIT_NAME_FULL)) { 2135 if (n->type == AUDIT_TYPE_UNKNOWN) 2136 n->type = type; 2137 found_child = n; 2138 break; 2139 } 2140 } 2141 2142 if (!found_parent) { 2143 /* create a new, "anonymous" parent record */ 2144 n = audit_alloc_name(context, AUDIT_TYPE_PARENT); 2145 if (!n) 2146 return; 2147 audit_copy_inode(n, NULL, parent, 0); 2148 } 2149 2150 if (!found_child) { 2151 found_child = audit_alloc_name(context, type); 2152 if (!found_child) 2153 return; 2154 2155 /* Re-use the name belonging to the slot for a matching parent 2156 * directory. All names for this context are relinquished in 2157 * audit_free_names() */ 2158 if (found_parent) { 2159 found_child->name = found_parent->name; 2160 found_child->name_len = AUDIT_NAME_FULL; 2161 found_child->name->refcnt++; 2162 } 2163 } 2164 2165 if (inode) 2166 audit_copy_inode(found_child, dentry, inode, 0); 2167 else 2168 found_child->ino = AUDIT_INO_UNSET; 2169 } 2170 EXPORT_SYMBOL_GPL(__audit_inode_child); 2171 2172 /** 2173 * auditsc_get_stamp - get local copies of audit_context values 2174 * @ctx: audit_context for the task 2175 * @t: timespec64 to store time recorded in the audit_context 2176 * @serial: serial value that is recorded in the audit_context 2177 * 2178 * Also sets the context as auditable. 2179 */ 2180 int auditsc_get_stamp(struct audit_context *ctx, 2181 struct timespec64 *t, unsigned int *serial) 2182 { 2183 if (!ctx->in_syscall) 2184 return 0; 2185 if (!ctx->serial) 2186 ctx->serial = audit_serial(); 2187 t->tv_sec = ctx->ctime.tv_sec; 2188 t->tv_nsec = ctx->ctime.tv_nsec; 2189 *serial = ctx->serial; 2190 if (!ctx->prio) { 2191 ctx->prio = 1; 2192 ctx->current_state = AUDIT_RECORD_CONTEXT; 2193 } 2194 return 1; 2195 } 2196 2197 /** 2198 * __audit_mq_open - record audit data for a POSIX MQ open 2199 * @oflag: open flag 2200 * @mode: mode bits 2201 * @attr: queue attributes 2202 * 2203 */ 2204 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr) 2205 { 2206 struct audit_context *context = audit_context(); 2207 2208 if (attr) 2209 memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr)); 2210 else 2211 memset(&context->mq_open.attr, 0, sizeof(struct mq_attr)); 2212 2213 context->mq_open.oflag = oflag; 2214 context->mq_open.mode = mode; 2215 2216 context->type = AUDIT_MQ_OPEN; 2217 } 2218 2219 /** 2220 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive 2221 * @mqdes: MQ descriptor 2222 * @msg_len: Message length 2223 * @msg_prio: Message priority 2224 * @abs_timeout: Message timeout in absolute time 2225 * 2226 */ 2227 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, 2228 const struct timespec64 *abs_timeout) 2229 { 2230 struct audit_context *context = audit_context(); 2231 struct timespec64 *p = &context->mq_sendrecv.abs_timeout; 2232 2233 if (abs_timeout) 2234 memcpy(p, abs_timeout, sizeof(*p)); 2235 else 2236 memset(p, 0, sizeof(*p)); 2237 2238 context->mq_sendrecv.mqdes = mqdes; 2239 context->mq_sendrecv.msg_len = msg_len; 2240 context->mq_sendrecv.msg_prio = msg_prio; 2241 2242 context->type = AUDIT_MQ_SENDRECV; 2243 } 2244 2245 /** 2246 * __audit_mq_notify - record audit data for a POSIX MQ notify 2247 * @mqdes: MQ descriptor 2248 * @notification: Notification event 2249 * 2250 */ 2251 2252 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification) 2253 { 2254 struct audit_context *context = audit_context(); 2255 2256 if (notification) 2257 context->mq_notify.sigev_signo = notification->sigev_signo; 2258 else 2259 context->mq_notify.sigev_signo = 0; 2260 2261 context->mq_notify.mqdes = mqdes; 2262 context->type = AUDIT_MQ_NOTIFY; 2263 } 2264 2265 /** 2266 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute 2267 * @mqdes: MQ descriptor 2268 * @mqstat: MQ flags 2269 * 2270 */ 2271 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) 2272 { 2273 struct audit_context *context = audit_context(); 2274 context->mq_getsetattr.mqdes = mqdes; 2275 context->mq_getsetattr.mqstat = *mqstat; 2276 context->type = AUDIT_MQ_GETSETATTR; 2277 } 2278 2279 /** 2280 * __audit_ipc_obj - record audit data for ipc object 2281 * @ipcp: ipc permissions 2282 * 2283 */ 2284 void __audit_ipc_obj(struct kern_ipc_perm *ipcp) 2285 { 2286 struct audit_context *context = audit_context(); 2287 context->ipc.uid = ipcp->uid; 2288 context->ipc.gid = ipcp->gid; 2289 context->ipc.mode = ipcp->mode; 2290 context->ipc.has_perm = 0; 2291 security_ipc_getsecid(ipcp, &context->ipc.osid); 2292 context->type = AUDIT_IPC; 2293 } 2294 2295 /** 2296 * __audit_ipc_set_perm - record audit data for new ipc permissions 2297 * @qbytes: msgq bytes 2298 * @uid: msgq user id 2299 * @gid: msgq group id 2300 * @mode: msgq mode (permissions) 2301 * 2302 * Called only after audit_ipc_obj(). 2303 */ 2304 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode) 2305 { 2306 struct audit_context *context = audit_context(); 2307 2308 context->ipc.qbytes = qbytes; 2309 context->ipc.perm_uid = uid; 2310 context->ipc.perm_gid = gid; 2311 context->ipc.perm_mode = mode; 2312 context->ipc.has_perm = 1; 2313 } 2314 2315 void __audit_bprm(struct linux_binprm *bprm) 2316 { 2317 struct audit_context *context = audit_context(); 2318 2319 context->type = AUDIT_EXECVE; 2320 context->execve.argc = bprm->argc; 2321 } 2322 2323 2324 /** 2325 * __audit_socketcall - record audit data for sys_socketcall 2326 * @nargs: number of args, which should not be more than AUDITSC_ARGS. 2327 * @args: args array 2328 * 2329 */ 2330 int __audit_socketcall(int nargs, unsigned long *args) 2331 { 2332 struct audit_context *context = audit_context(); 2333 2334 if (nargs <= 0 || nargs > AUDITSC_ARGS || !args) 2335 return -EINVAL; 2336 context->type = AUDIT_SOCKETCALL; 2337 context->socketcall.nargs = nargs; 2338 memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long)); 2339 return 0; 2340 } 2341 2342 /** 2343 * __audit_fd_pair - record audit data for pipe and socketpair 2344 * @fd1: the first file descriptor 2345 * @fd2: the second file descriptor 2346 * 2347 */ 2348 void __audit_fd_pair(int fd1, int fd2) 2349 { 2350 struct audit_context *context = audit_context(); 2351 context->fds[0] = fd1; 2352 context->fds[1] = fd2; 2353 } 2354 2355 /** 2356 * __audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto 2357 * @len: data length in user space 2358 * @a: data address in kernel space 2359 * 2360 * Returns 0 for success or NULL context or < 0 on error. 2361 */ 2362 int __audit_sockaddr(int len, void *a) 2363 { 2364 struct audit_context *context = audit_context(); 2365 2366 if (!context->sockaddr) { 2367 void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL); 2368 if (!p) 2369 return -ENOMEM; 2370 context->sockaddr = p; 2371 } 2372 2373 context->sockaddr_len = len; 2374 memcpy(context->sockaddr, a, len); 2375 return 0; 2376 } 2377 2378 void __audit_ptrace(struct task_struct *t) 2379 { 2380 struct audit_context *context = audit_context(); 2381 2382 context->target_pid = task_tgid_nr(t); 2383 context->target_auid = audit_get_loginuid(t); 2384 context->target_uid = task_uid(t); 2385 context->target_sessionid = audit_get_sessionid(t); 2386 security_task_getsecid(t, &context->target_sid); 2387 memcpy(context->target_comm, t->comm, TASK_COMM_LEN); 2388 } 2389 2390 /** 2391 * audit_signal_info_syscall - record signal info for syscalls 2392 * @t: task being signaled 2393 * 2394 * If the audit subsystem is being terminated, record the task (pid) 2395 * and uid that is doing that. 2396 */ 2397 int audit_signal_info_syscall(struct task_struct *t) 2398 { 2399 struct audit_aux_data_pids *axp; 2400 struct audit_context *ctx = audit_context(); 2401 kuid_t t_uid = task_uid(t); 2402 2403 if (!audit_signals || audit_dummy_context()) 2404 return 0; 2405 2406 /* optimize the common case by putting first signal recipient directly 2407 * in audit_context */ 2408 if (!ctx->target_pid) { 2409 ctx->target_pid = task_tgid_nr(t); 2410 ctx->target_auid = audit_get_loginuid(t); 2411 ctx->target_uid = t_uid; 2412 ctx->target_sessionid = audit_get_sessionid(t); 2413 security_task_getsecid(t, &ctx->target_sid); 2414 memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); 2415 return 0; 2416 } 2417 2418 axp = (void *)ctx->aux_pids; 2419 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { 2420 axp = kzalloc(sizeof(*axp), GFP_ATOMIC); 2421 if (!axp) 2422 return -ENOMEM; 2423 2424 axp->d.type = AUDIT_OBJ_PID; 2425 axp->d.next = ctx->aux_pids; 2426 ctx->aux_pids = (void *)axp; 2427 } 2428 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); 2429 2430 axp->target_pid[axp->pid_count] = task_tgid_nr(t); 2431 axp->target_auid[axp->pid_count] = audit_get_loginuid(t); 2432 axp->target_uid[axp->pid_count] = t_uid; 2433 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); 2434 security_task_getsecid(t, &axp->target_sid[axp->pid_count]); 2435 memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); 2436 axp->pid_count++; 2437 2438 return 0; 2439 } 2440 2441 /** 2442 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps 2443 * @bprm: pointer to the bprm being processed 2444 * @new: the proposed new credentials 2445 * @old: the old credentials 2446 * 2447 * Simply check if the proc already has the caps given by the file and if not 2448 * store the priv escalation info for later auditing at the end of the syscall 2449 * 2450 * -Eric 2451 */ 2452 int __audit_log_bprm_fcaps(struct linux_binprm *bprm, 2453 const struct cred *new, const struct cred *old) 2454 { 2455 struct audit_aux_data_bprm_fcaps *ax; 2456 struct audit_context *context = audit_context(); 2457 struct cpu_vfs_cap_data vcaps; 2458 2459 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2460 if (!ax) 2461 return -ENOMEM; 2462 2463 ax->d.type = AUDIT_BPRM_FCAPS; 2464 ax->d.next = context->aux; 2465 context->aux = (void *)ax; 2466 2467 get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps); 2468 2469 ax->fcap.permitted = vcaps.permitted; 2470 ax->fcap.inheritable = vcaps.inheritable; 2471 ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 2472 ax->fcap.rootid = vcaps.rootid; 2473 ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; 2474 2475 ax->old_pcap.permitted = old->cap_permitted; 2476 ax->old_pcap.inheritable = old->cap_inheritable; 2477 ax->old_pcap.effective = old->cap_effective; 2478 ax->old_pcap.ambient = old->cap_ambient; 2479 2480 ax->new_pcap.permitted = new->cap_permitted; 2481 ax->new_pcap.inheritable = new->cap_inheritable; 2482 ax->new_pcap.effective = new->cap_effective; 2483 ax->new_pcap.ambient = new->cap_ambient; 2484 return 0; 2485 } 2486 2487 /** 2488 * __audit_log_capset - store information about the arguments to the capset syscall 2489 * @new: the new credentials 2490 * @old: the old (current) credentials 2491 * 2492 * Record the arguments userspace sent to sys_capset for later printing by the 2493 * audit system if applicable 2494 */ 2495 void __audit_log_capset(const struct cred *new, const struct cred *old) 2496 { 2497 struct audit_context *context = audit_context(); 2498 context->capset.pid = task_tgid_nr(current); 2499 context->capset.cap.effective = new->cap_effective; 2500 context->capset.cap.inheritable = new->cap_effective; 2501 context->capset.cap.permitted = new->cap_permitted; 2502 context->capset.cap.ambient = new->cap_ambient; 2503 context->type = AUDIT_CAPSET; 2504 } 2505 2506 void __audit_mmap_fd(int fd, int flags) 2507 { 2508 struct audit_context *context = audit_context(); 2509 context->mmap.fd = fd; 2510 context->mmap.flags = flags; 2511 context->type = AUDIT_MMAP; 2512 } 2513 2514 void __audit_log_kern_module(char *name) 2515 { 2516 struct audit_context *context = audit_context(); 2517 2518 context->module.name = kstrdup(name, GFP_KERNEL); 2519 if (!context->module.name) 2520 audit_log_lost("out of memory in __audit_log_kern_module"); 2521 context->type = AUDIT_KERN_MODULE; 2522 } 2523 2524 void __audit_fanotify(unsigned int response) 2525 { 2526 audit_log(audit_context(), GFP_KERNEL, 2527 AUDIT_FANOTIFY, "resp=%u", response); 2528 } 2529 2530 void __audit_tk_injoffset(struct timespec64 offset) 2531 { 2532 audit_log(audit_context(), GFP_KERNEL, AUDIT_TIME_INJOFFSET, 2533 "sec=%lli nsec=%li", 2534 (long long)offset.tv_sec, offset.tv_nsec); 2535 } 2536 2537 static void audit_log_ntp_val(const struct audit_ntp_data *ad, 2538 const char *op, enum audit_ntp_type type) 2539 { 2540 const struct audit_ntp_val *val = &ad->vals[type]; 2541 2542 if (val->newval == val->oldval) 2543 return; 2544 2545 audit_log(audit_context(), GFP_KERNEL, AUDIT_TIME_ADJNTPVAL, 2546 "op=%s old=%lli new=%lli", op, val->oldval, val->newval); 2547 } 2548 2549 void __audit_ntp_log(const struct audit_ntp_data *ad) 2550 { 2551 audit_log_ntp_val(ad, "offset", AUDIT_NTP_OFFSET); 2552 audit_log_ntp_val(ad, "freq", AUDIT_NTP_FREQ); 2553 audit_log_ntp_val(ad, "status", AUDIT_NTP_STATUS); 2554 audit_log_ntp_val(ad, "tai", AUDIT_NTP_TAI); 2555 audit_log_ntp_val(ad, "tick", AUDIT_NTP_TICK); 2556 audit_log_ntp_val(ad, "adjust", AUDIT_NTP_ADJUST); 2557 } 2558 2559 void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries, 2560 enum audit_nfcfgop op) 2561 { 2562 struct audit_buffer *ab; 2563 char comm[sizeof(current->comm)]; 2564 2565 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_NETFILTER_CFG); 2566 if (!ab) 2567 return; 2568 audit_log_format(ab, "table=%s family=%u entries=%u op=%s", 2569 name, af, nentries, audit_nfcfgs[op].s); 2570 2571 audit_log_format(ab, " pid=%u", task_pid_nr(current)); 2572 audit_log_task_context(ab); /* subj= */ 2573 audit_log_format(ab, " comm="); 2574 audit_log_untrustedstring(ab, get_task_comm(comm, current)); 2575 audit_log_end(ab); 2576 } 2577 EXPORT_SYMBOL_GPL(__audit_log_nfcfg); 2578 2579 static void audit_log_task(struct audit_buffer *ab) 2580 { 2581 kuid_t auid, uid; 2582 kgid_t gid; 2583 unsigned int sessionid; 2584 char comm[sizeof(current->comm)]; 2585 2586 auid = audit_get_loginuid(current); 2587 sessionid = audit_get_sessionid(current); 2588 current_uid_gid(&uid, &gid); 2589 2590 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", 2591 from_kuid(&init_user_ns, auid), 2592 from_kuid(&init_user_ns, uid), 2593 from_kgid(&init_user_ns, gid), 2594 sessionid); 2595 audit_log_task_context(ab); 2596 audit_log_format(ab, " pid=%d comm=", task_tgid_nr(current)); 2597 audit_log_untrustedstring(ab, get_task_comm(comm, current)); 2598 audit_log_d_path_exe(ab, current->mm); 2599 } 2600 2601 /** 2602 * audit_core_dumps - record information about processes that end abnormally 2603 * @signr: signal value 2604 * 2605 * If a process ends with a core dump, something fishy is going on and we 2606 * should record the event for investigation. 2607 */ 2608 void audit_core_dumps(long signr) 2609 { 2610 struct audit_buffer *ab; 2611 2612 if (!audit_enabled) 2613 return; 2614 2615 if (signr == SIGQUIT) /* don't care for those */ 2616 return; 2617 2618 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_ANOM_ABEND); 2619 if (unlikely(!ab)) 2620 return; 2621 audit_log_task(ab); 2622 audit_log_format(ab, " sig=%ld res=1", signr); 2623 audit_log_end(ab); 2624 } 2625 2626 /** 2627 * audit_seccomp - record information about a seccomp action 2628 * @syscall: syscall number 2629 * @signr: signal value 2630 * @code: the seccomp action 2631 * 2632 * Record the information associated with a seccomp action. Event filtering for 2633 * seccomp actions that are not to be logged is done in seccomp_log(). 2634 * Therefore, this function forces auditing independent of the audit_enabled 2635 * and dummy context state because seccomp actions should be logged even when 2636 * audit is not in use. 2637 */ 2638 void audit_seccomp(unsigned long syscall, long signr, int code) 2639 { 2640 struct audit_buffer *ab; 2641 2642 ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_SECCOMP); 2643 if (unlikely(!ab)) 2644 return; 2645 audit_log_task(ab); 2646 audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x", 2647 signr, syscall_get_arch(current), syscall, 2648 in_compat_syscall(), KSTK_EIP(current), code); 2649 audit_log_end(ab); 2650 } 2651 2652 void audit_seccomp_actions_logged(const char *names, const char *old_names, 2653 int res) 2654 { 2655 struct audit_buffer *ab; 2656 2657 if (!audit_enabled) 2658 return; 2659 2660 ab = audit_log_start(audit_context(), GFP_KERNEL, 2661 AUDIT_CONFIG_CHANGE); 2662 if (unlikely(!ab)) 2663 return; 2664 2665 audit_log_format(ab, 2666 "op=seccomp-logging actions=%s old-actions=%s res=%d", 2667 names, old_names, res); 2668 audit_log_end(ab); 2669 } 2670 2671 struct list_head *audit_killed_trees(void) 2672 { 2673 struct audit_context *ctx = audit_context(); 2674 if (likely(!ctx || !ctx->in_syscall)) 2675 return NULL; 2676 return &ctx->killed_trees; 2677 } 2678