1 /* auditsc.c -- System-call auditing support 2 * Handles all system-call specific auditing features. 3 * 4 * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina. 5 * Copyright 2005 Hewlett-Packard Development Company, L.P. 6 * Copyright (C) 2005, 2006 IBM Corporation 7 * All Rights Reserved. 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or 12 * (at your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 22 * 23 * Written by Rickard E. (Rik) Faith <faith@redhat.com> 24 * 25 * Many of the ideas implemented here are from Stephen C. Tweedie, 26 * especially the idea of avoiding a copy by using getname. 27 * 28 * The method for actual interception of syscall entry and exit (not in 29 * this file -- see entry.S) is based on a GPL'd patch written by 30 * okir@suse.de and Copyright 2003 SuSE Linux AG. 31 * 32 * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>, 33 * 2006. 34 * 35 * The support of additional filter rules compares (>, <, >=, <=) was 36 * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005. 37 * 38 * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional 39 * filesystem information. 40 * 41 * Subject and object context labeling support added by <danjones@us.ibm.com> 42 * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance. 43 */ 44 45 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 46 47 #include <linux/init.h> 48 #include <asm/types.h> 49 #include <linux/atomic.h> 50 #include <linux/fs.h> 51 #include <linux/namei.h> 52 #include <linux/mm.h> 53 #include <linux/export.h> 54 #include <linux/slab.h> 55 #include <linux/mount.h> 56 #include <linux/socket.h> 57 #include <linux/mqueue.h> 58 #include <linux/audit.h> 59 #include <linux/personality.h> 60 #include <linux/time.h> 61 #include <linux/netlink.h> 62 #include <linux/compiler.h> 63 #include <asm/unistd.h> 64 #include <linux/security.h> 65 #include <linux/list.h> 66 #include <linux/binfmts.h> 67 #include <linux/highmem.h> 68 #include <linux/syscalls.h> 69 #include <asm/syscall.h> 70 #include <linux/capability.h> 71 #include <linux/fs_struct.h> 72 #include <linux/compat.h> 73 #include <linux/ctype.h> 74 #include <linux/string.h> 75 #include <linux/uaccess.h> 76 #include <linux/fsnotify_backend.h> 77 #include <uapi/linux/limits.h> 78 79 #include "audit.h" 80 81 /* flags stating the success for a syscall */ 82 #define AUDITSC_INVALID 0 83 #define AUDITSC_SUCCESS 1 84 #define AUDITSC_FAILURE 2 85 86 /* no execve audit message should be longer than this (userspace limits), 87 * see the note near the top of audit_log_execve_info() about this value */ 88 #define MAX_EXECVE_AUDIT_LEN 7500 89 90 /* max length to print of cmdline/proctitle value during audit */ 91 #define MAX_PROCTITLE_AUDIT_LEN 128 92 93 /* number of audit rules */ 94 int audit_n_rules; 95 96 /* determines whether we collect data for signals sent */ 97 int audit_signals; 98 99 struct audit_aux_data { 100 struct audit_aux_data *next; 101 int type; 102 }; 103 104 #define AUDIT_AUX_IPCPERM 0 105 106 /* Number of target pids per aux struct. */ 107 #define AUDIT_AUX_PIDS 16 108 109 struct audit_aux_data_pids { 110 struct audit_aux_data d; 111 pid_t target_pid[AUDIT_AUX_PIDS]; 112 kuid_t target_auid[AUDIT_AUX_PIDS]; 113 kuid_t target_uid[AUDIT_AUX_PIDS]; 114 unsigned int target_sessionid[AUDIT_AUX_PIDS]; 115 u32 target_sid[AUDIT_AUX_PIDS]; 116 char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN]; 117 int pid_count; 118 }; 119 120 struct audit_aux_data_bprm_fcaps { 121 struct audit_aux_data d; 122 struct audit_cap_data fcap; 123 unsigned int fcap_ver; 124 struct audit_cap_data old_pcap; 125 struct audit_cap_data new_pcap; 126 }; 127 128 struct audit_tree_refs { 129 struct audit_tree_refs *next; 130 struct audit_chunk *c[31]; 131 }; 132 133 static int audit_match_perm(struct audit_context *ctx, int mask) 134 { 135 unsigned n; 136 if (unlikely(!ctx)) 137 return 0; 138 n = ctx->major; 139 140 switch (audit_classify_syscall(ctx->arch, n)) { 141 case 0: /* native */ 142 if ((mask & AUDIT_PERM_WRITE) && 143 audit_match_class(AUDIT_CLASS_WRITE, n)) 144 return 1; 145 if ((mask & AUDIT_PERM_READ) && 146 audit_match_class(AUDIT_CLASS_READ, n)) 147 return 1; 148 if ((mask & AUDIT_PERM_ATTR) && 149 audit_match_class(AUDIT_CLASS_CHATTR, n)) 150 return 1; 151 return 0; 152 case 1: /* 32bit on biarch */ 153 if ((mask & AUDIT_PERM_WRITE) && 154 audit_match_class(AUDIT_CLASS_WRITE_32, n)) 155 return 1; 156 if ((mask & AUDIT_PERM_READ) && 157 audit_match_class(AUDIT_CLASS_READ_32, n)) 158 return 1; 159 if ((mask & AUDIT_PERM_ATTR) && 160 audit_match_class(AUDIT_CLASS_CHATTR_32, n)) 161 return 1; 162 return 0; 163 case 2: /* open */ 164 return mask & ACC_MODE(ctx->argv[1]); 165 case 3: /* openat */ 166 return mask & ACC_MODE(ctx->argv[2]); 167 case 4: /* socketcall */ 168 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); 169 case 5: /* execve */ 170 return mask & AUDIT_PERM_EXEC; 171 default: 172 return 0; 173 } 174 } 175 176 static int audit_match_filetype(struct audit_context *ctx, int val) 177 { 178 struct audit_names *n; 179 umode_t mode = (umode_t)val; 180 181 if (unlikely(!ctx)) 182 return 0; 183 184 list_for_each_entry(n, &ctx->names_list, list) { 185 if ((n->ino != AUDIT_INO_UNSET) && 186 ((n->mode & S_IFMT) == mode)) 187 return 1; 188 } 189 190 return 0; 191 } 192 193 /* 194 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *; 195 * ->first_trees points to its beginning, ->trees - to the current end of data. 196 * ->tree_count is the number of free entries in array pointed to by ->trees. 197 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL, 198 * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously, 199 * it's going to remain 1-element for almost any setup) until we free context itself. 200 * References in it _are_ dropped - at the same time we free/drop aux stuff. 201 */ 202 203 #ifdef CONFIG_AUDIT_TREE 204 static void audit_set_auditable(struct audit_context *ctx) 205 { 206 if (!ctx->prio) { 207 ctx->prio = 1; 208 ctx->current_state = AUDIT_RECORD_CONTEXT; 209 } 210 } 211 212 static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk) 213 { 214 struct audit_tree_refs *p = ctx->trees; 215 int left = ctx->tree_count; 216 if (likely(left)) { 217 p->c[--left] = chunk; 218 ctx->tree_count = left; 219 return 1; 220 } 221 if (!p) 222 return 0; 223 p = p->next; 224 if (p) { 225 p->c[30] = chunk; 226 ctx->trees = p; 227 ctx->tree_count = 30; 228 return 1; 229 } 230 return 0; 231 } 232 233 static int grow_tree_refs(struct audit_context *ctx) 234 { 235 struct audit_tree_refs *p = ctx->trees; 236 ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL); 237 if (!ctx->trees) { 238 ctx->trees = p; 239 return 0; 240 } 241 if (p) 242 p->next = ctx->trees; 243 else 244 ctx->first_trees = ctx->trees; 245 ctx->tree_count = 31; 246 return 1; 247 } 248 #endif 249 250 static void unroll_tree_refs(struct audit_context *ctx, 251 struct audit_tree_refs *p, int count) 252 { 253 #ifdef CONFIG_AUDIT_TREE 254 struct audit_tree_refs *q; 255 int n; 256 if (!p) { 257 /* we started with empty chain */ 258 p = ctx->first_trees; 259 count = 31; 260 /* if the very first allocation has failed, nothing to do */ 261 if (!p) 262 return; 263 } 264 n = count; 265 for (q = p; q != ctx->trees; q = q->next, n = 31) { 266 while (n--) { 267 audit_put_chunk(q->c[n]); 268 q->c[n] = NULL; 269 } 270 } 271 while (n-- > ctx->tree_count) { 272 audit_put_chunk(q->c[n]); 273 q->c[n] = NULL; 274 } 275 ctx->trees = p; 276 ctx->tree_count = count; 277 #endif 278 } 279 280 static void free_tree_refs(struct audit_context *ctx) 281 { 282 struct audit_tree_refs *p, *q; 283 for (p = ctx->first_trees; p; p = q) { 284 q = p->next; 285 kfree(p); 286 } 287 } 288 289 static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree) 290 { 291 #ifdef CONFIG_AUDIT_TREE 292 struct audit_tree_refs *p; 293 int n; 294 if (!tree) 295 return 0; 296 /* full ones */ 297 for (p = ctx->first_trees; p != ctx->trees; p = p->next) { 298 for (n = 0; n < 31; n++) 299 if (audit_tree_match(p->c[n], tree)) 300 return 1; 301 } 302 /* partial */ 303 if (p) { 304 for (n = ctx->tree_count; n < 31; n++) 305 if (audit_tree_match(p->c[n], tree)) 306 return 1; 307 } 308 #endif 309 return 0; 310 } 311 312 static int audit_compare_uid(kuid_t uid, 313 struct audit_names *name, 314 struct audit_field *f, 315 struct audit_context *ctx) 316 { 317 struct audit_names *n; 318 int rc; 319 320 if (name) { 321 rc = audit_uid_comparator(uid, f->op, name->uid); 322 if (rc) 323 return rc; 324 } 325 326 if (ctx) { 327 list_for_each_entry(n, &ctx->names_list, list) { 328 rc = audit_uid_comparator(uid, f->op, n->uid); 329 if (rc) 330 return rc; 331 } 332 } 333 return 0; 334 } 335 336 static int audit_compare_gid(kgid_t gid, 337 struct audit_names *name, 338 struct audit_field *f, 339 struct audit_context *ctx) 340 { 341 struct audit_names *n; 342 int rc; 343 344 if (name) { 345 rc = audit_gid_comparator(gid, f->op, name->gid); 346 if (rc) 347 return rc; 348 } 349 350 if (ctx) { 351 list_for_each_entry(n, &ctx->names_list, list) { 352 rc = audit_gid_comparator(gid, f->op, n->gid); 353 if (rc) 354 return rc; 355 } 356 } 357 return 0; 358 } 359 360 static int audit_field_compare(struct task_struct *tsk, 361 const struct cred *cred, 362 struct audit_field *f, 363 struct audit_context *ctx, 364 struct audit_names *name) 365 { 366 switch (f->val) { 367 /* process to file object comparisons */ 368 case AUDIT_COMPARE_UID_TO_OBJ_UID: 369 return audit_compare_uid(cred->uid, name, f, ctx); 370 case AUDIT_COMPARE_GID_TO_OBJ_GID: 371 return audit_compare_gid(cred->gid, name, f, ctx); 372 case AUDIT_COMPARE_EUID_TO_OBJ_UID: 373 return audit_compare_uid(cred->euid, name, f, ctx); 374 case AUDIT_COMPARE_EGID_TO_OBJ_GID: 375 return audit_compare_gid(cred->egid, name, f, ctx); 376 case AUDIT_COMPARE_AUID_TO_OBJ_UID: 377 return audit_compare_uid(tsk->loginuid, name, f, ctx); 378 case AUDIT_COMPARE_SUID_TO_OBJ_UID: 379 return audit_compare_uid(cred->suid, name, f, ctx); 380 case AUDIT_COMPARE_SGID_TO_OBJ_GID: 381 return audit_compare_gid(cred->sgid, name, f, ctx); 382 case AUDIT_COMPARE_FSUID_TO_OBJ_UID: 383 return audit_compare_uid(cred->fsuid, name, f, ctx); 384 case AUDIT_COMPARE_FSGID_TO_OBJ_GID: 385 return audit_compare_gid(cred->fsgid, name, f, ctx); 386 /* uid comparisons */ 387 case AUDIT_COMPARE_UID_TO_AUID: 388 return audit_uid_comparator(cred->uid, f->op, tsk->loginuid); 389 case AUDIT_COMPARE_UID_TO_EUID: 390 return audit_uid_comparator(cred->uid, f->op, cred->euid); 391 case AUDIT_COMPARE_UID_TO_SUID: 392 return audit_uid_comparator(cred->uid, f->op, cred->suid); 393 case AUDIT_COMPARE_UID_TO_FSUID: 394 return audit_uid_comparator(cred->uid, f->op, cred->fsuid); 395 /* auid comparisons */ 396 case AUDIT_COMPARE_AUID_TO_EUID: 397 return audit_uid_comparator(tsk->loginuid, f->op, cred->euid); 398 case AUDIT_COMPARE_AUID_TO_SUID: 399 return audit_uid_comparator(tsk->loginuid, f->op, cred->suid); 400 case AUDIT_COMPARE_AUID_TO_FSUID: 401 return audit_uid_comparator(tsk->loginuid, f->op, cred->fsuid); 402 /* euid comparisons */ 403 case AUDIT_COMPARE_EUID_TO_SUID: 404 return audit_uid_comparator(cred->euid, f->op, cred->suid); 405 case AUDIT_COMPARE_EUID_TO_FSUID: 406 return audit_uid_comparator(cred->euid, f->op, cred->fsuid); 407 /* suid comparisons */ 408 case AUDIT_COMPARE_SUID_TO_FSUID: 409 return audit_uid_comparator(cred->suid, f->op, cred->fsuid); 410 /* gid comparisons */ 411 case AUDIT_COMPARE_GID_TO_EGID: 412 return audit_gid_comparator(cred->gid, f->op, cred->egid); 413 case AUDIT_COMPARE_GID_TO_SGID: 414 return audit_gid_comparator(cred->gid, f->op, cred->sgid); 415 case AUDIT_COMPARE_GID_TO_FSGID: 416 return audit_gid_comparator(cred->gid, f->op, cred->fsgid); 417 /* egid comparisons */ 418 case AUDIT_COMPARE_EGID_TO_SGID: 419 return audit_gid_comparator(cred->egid, f->op, cred->sgid); 420 case AUDIT_COMPARE_EGID_TO_FSGID: 421 return audit_gid_comparator(cred->egid, f->op, cred->fsgid); 422 /* sgid comparison */ 423 case AUDIT_COMPARE_SGID_TO_FSGID: 424 return audit_gid_comparator(cred->sgid, f->op, cred->fsgid); 425 default: 426 WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n"); 427 return 0; 428 } 429 return 0; 430 } 431 432 /* Determine if any context name data matches a rule's watch data */ 433 /* Compare a task_struct with an audit_rule. Return 1 on match, 0 434 * otherwise. 435 * 436 * If task_creation is true, this is an explicit indication that we are 437 * filtering a task rule at task creation time. This and tsk == current are 438 * the only situations where tsk->cred may be accessed without an rcu read lock. 439 */ 440 static int audit_filter_rules(struct task_struct *tsk, 441 struct audit_krule *rule, 442 struct audit_context *ctx, 443 struct audit_names *name, 444 enum audit_state *state, 445 bool task_creation) 446 { 447 const struct cred *cred; 448 int i, need_sid = 1; 449 u32 sid; 450 unsigned int sessionid; 451 452 cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation); 453 454 for (i = 0; i < rule->field_count; i++) { 455 struct audit_field *f = &rule->fields[i]; 456 struct audit_names *n; 457 int result = 0; 458 pid_t pid; 459 460 switch (f->type) { 461 case AUDIT_PID: 462 pid = task_tgid_nr(tsk); 463 result = audit_comparator(pid, f->op, f->val); 464 break; 465 case AUDIT_PPID: 466 if (ctx) { 467 if (!ctx->ppid) 468 ctx->ppid = task_ppid_nr(tsk); 469 result = audit_comparator(ctx->ppid, f->op, f->val); 470 } 471 break; 472 case AUDIT_EXE: 473 result = audit_exe_compare(tsk, rule->exe); 474 break; 475 case AUDIT_UID: 476 result = audit_uid_comparator(cred->uid, f->op, f->uid); 477 break; 478 case AUDIT_EUID: 479 result = audit_uid_comparator(cred->euid, f->op, f->uid); 480 break; 481 case AUDIT_SUID: 482 result = audit_uid_comparator(cred->suid, f->op, f->uid); 483 break; 484 case AUDIT_FSUID: 485 result = audit_uid_comparator(cred->fsuid, f->op, f->uid); 486 break; 487 case AUDIT_GID: 488 result = audit_gid_comparator(cred->gid, f->op, f->gid); 489 if (f->op == Audit_equal) { 490 if (!result) 491 result = in_group_p(f->gid); 492 } else if (f->op == Audit_not_equal) { 493 if (result) 494 result = !in_group_p(f->gid); 495 } 496 break; 497 case AUDIT_EGID: 498 result = audit_gid_comparator(cred->egid, f->op, f->gid); 499 if (f->op == Audit_equal) { 500 if (!result) 501 result = in_egroup_p(f->gid); 502 } else if (f->op == Audit_not_equal) { 503 if (result) 504 result = !in_egroup_p(f->gid); 505 } 506 break; 507 case AUDIT_SGID: 508 result = audit_gid_comparator(cred->sgid, f->op, f->gid); 509 break; 510 case AUDIT_FSGID: 511 result = audit_gid_comparator(cred->fsgid, f->op, f->gid); 512 break; 513 case AUDIT_SESSIONID: 514 sessionid = audit_get_sessionid(current); 515 result = audit_comparator(sessionid, f->op, f->val); 516 break; 517 case AUDIT_PERS: 518 result = audit_comparator(tsk->personality, f->op, f->val); 519 break; 520 case AUDIT_ARCH: 521 if (ctx) 522 result = audit_comparator(ctx->arch, f->op, f->val); 523 break; 524 525 case AUDIT_EXIT: 526 if (ctx && ctx->return_valid) 527 result = audit_comparator(ctx->return_code, f->op, f->val); 528 break; 529 case AUDIT_SUCCESS: 530 if (ctx && ctx->return_valid) { 531 if (f->val) 532 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS); 533 else 534 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE); 535 } 536 break; 537 case AUDIT_DEVMAJOR: 538 if (name) { 539 if (audit_comparator(MAJOR(name->dev), f->op, f->val) || 540 audit_comparator(MAJOR(name->rdev), f->op, f->val)) 541 ++result; 542 } else if (ctx) { 543 list_for_each_entry(n, &ctx->names_list, list) { 544 if (audit_comparator(MAJOR(n->dev), f->op, f->val) || 545 audit_comparator(MAJOR(n->rdev), f->op, f->val)) { 546 ++result; 547 break; 548 } 549 } 550 } 551 break; 552 case AUDIT_DEVMINOR: 553 if (name) { 554 if (audit_comparator(MINOR(name->dev), f->op, f->val) || 555 audit_comparator(MINOR(name->rdev), f->op, f->val)) 556 ++result; 557 } else if (ctx) { 558 list_for_each_entry(n, &ctx->names_list, list) { 559 if (audit_comparator(MINOR(n->dev), f->op, f->val) || 560 audit_comparator(MINOR(n->rdev), f->op, f->val)) { 561 ++result; 562 break; 563 } 564 } 565 } 566 break; 567 case AUDIT_INODE: 568 if (name) 569 result = audit_comparator(name->ino, f->op, f->val); 570 else if (ctx) { 571 list_for_each_entry(n, &ctx->names_list, list) { 572 if (audit_comparator(n->ino, f->op, f->val)) { 573 ++result; 574 break; 575 } 576 } 577 } 578 break; 579 case AUDIT_OBJ_UID: 580 if (name) { 581 result = audit_uid_comparator(name->uid, f->op, f->uid); 582 } else if (ctx) { 583 list_for_each_entry(n, &ctx->names_list, list) { 584 if (audit_uid_comparator(n->uid, f->op, f->uid)) { 585 ++result; 586 break; 587 } 588 } 589 } 590 break; 591 case AUDIT_OBJ_GID: 592 if (name) { 593 result = audit_gid_comparator(name->gid, f->op, f->gid); 594 } else if (ctx) { 595 list_for_each_entry(n, &ctx->names_list, list) { 596 if (audit_gid_comparator(n->gid, f->op, f->gid)) { 597 ++result; 598 break; 599 } 600 } 601 } 602 break; 603 case AUDIT_WATCH: 604 if (name) 605 result = audit_watch_compare(rule->watch, name->ino, name->dev); 606 break; 607 case AUDIT_DIR: 608 if (ctx) 609 result = match_tree_refs(ctx, rule->tree); 610 break; 611 case AUDIT_LOGINUID: 612 result = audit_uid_comparator(tsk->loginuid, f->op, f->uid); 613 break; 614 case AUDIT_LOGINUID_SET: 615 result = audit_comparator(audit_loginuid_set(tsk), f->op, f->val); 616 break; 617 case AUDIT_SUBJ_USER: 618 case AUDIT_SUBJ_ROLE: 619 case AUDIT_SUBJ_TYPE: 620 case AUDIT_SUBJ_SEN: 621 case AUDIT_SUBJ_CLR: 622 /* NOTE: this may return negative values indicating 623 a temporary error. We simply treat this as a 624 match for now to avoid losing information that 625 may be wanted. An error message will also be 626 logged upon error */ 627 if (f->lsm_rule) { 628 if (need_sid) { 629 security_task_getsecid(tsk, &sid); 630 need_sid = 0; 631 } 632 result = security_audit_rule_match(sid, f->type, 633 f->op, 634 f->lsm_rule, 635 ctx); 636 } 637 break; 638 case AUDIT_OBJ_USER: 639 case AUDIT_OBJ_ROLE: 640 case AUDIT_OBJ_TYPE: 641 case AUDIT_OBJ_LEV_LOW: 642 case AUDIT_OBJ_LEV_HIGH: 643 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR 644 also applies here */ 645 if (f->lsm_rule) { 646 /* Find files that match */ 647 if (name) { 648 result = security_audit_rule_match( 649 name->osid, f->type, f->op, 650 f->lsm_rule, ctx); 651 } else if (ctx) { 652 list_for_each_entry(n, &ctx->names_list, list) { 653 if (security_audit_rule_match(n->osid, f->type, 654 f->op, f->lsm_rule, 655 ctx)) { 656 ++result; 657 break; 658 } 659 } 660 } 661 /* Find ipc objects that match */ 662 if (!ctx || ctx->type != AUDIT_IPC) 663 break; 664 if (security_audit_rule_match(ctx->ipc.osid, 665 f->type, f->op, 666 f->lsm_rule, ctx)) 667 ++result; 668 } 669 break; 670 case AUDIT_ARG0: 671 case AUDIT_ARG1: 672 case AUDIT_ARG2: 673 case AUDIT_ARG3: 674 if (ctx) 675 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val); 676 break; 677 case AUDIT_FILTERKEY: 678 /* ignore this field for filtering */ 679 result = 1; 680 break; 681 case AUDIT_PERM: 682 result = audit_match_perm(ctx, f->val); 683 break; 684 case AUDIT_FILETYPE: 685 result = audit_match_filetype(ctx, f->val); 686 break; 687 case AUDIT_FIELD_COMPARE: 688 result = audit_field_compare(tsk, cred, f, ctx, name); 689 break; 690 } 691 if (!result) 692 return 0; 693 } 694 695 if (ctx) { 696 if (rule->prio <= ctx->prio) 697 return 0; 698 if (rule->filterkey) { 699 kfree(ctx->filterkey); 700 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC); 701 } 702 ctx->prio = rule->prio; 703 } 704 switch (rule->action) { 705 case AUDIT_NEVER: 706 *state = AUDIT_DISABLED; 707 break; 708 case AUDIT_ALWAYS: 709 *state = AUDIT_RECORD_CONTEXT; 710 break; 711 } 712 return 1; 713 } 714 715 /* At process creation time, we can determine if system-call auditing is 716 * completely disabled for this task. Since we only have the task 717 * structure at this point, we can only check uid and gid. 718 */ 719 static enum audit_state audit_filter_task(struct task_struct *tsk, char **key) 720 { 721 struct audit_entry *e; 722 enum audit_state state; 723 724 rcu_read_lock(); 725 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { 726 if (audit_filter_rules(tsk, &e->rule, NULL, NULL, 727 &state, true)) { 728 if (state == AUDIT_RECORD_CONTEXT) 729 *key = kstrdup(e->rule.filterkey, GFP_ATOMIC); 730 rcu_read_unlock(); 731 return state; 732 } 733 } 734 rcu_read_unlock(); 735 return AUDIT_BUILD_CONTEXT; 736 } 737 738 static int audit_in_mask(const struct audit_krule *rule, unsigned long val) 739 { 740 int word, bit; 741 742 if (val > 0xffffffff) 743 return false; 744 745 word = AUDIT_WORD(val); 746 if (word >= AUDIT_BITMASK_SIZE) 747 return false; 748 749 bit = AUDIT_BIT(val); 750 751 return rule->mask[word] & bit; 752 } 753 754 /* At syscall entry and exit time, this filter is called if the 755 * audit_state is not low enough that auditing cannot take place, but is 756 * also not high enough that we already know we have to write an audit 757 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). 758 */ 759 static enum audit_state audit_filter_syscall(struct task_struct *tsk, 760 struct audit_context *ctx, 761 struct list_head *list) 762 { 763 struct audit_entry *e; 764 enum audit_state state; 765 766 if (auditd_test_task(tsk)) 767 return AUDIT_DISABLED; 768 769 rcu_read_lock(); 770 if (!list_empty(list)) { 771 list_for_each_entry_rcu(e, list, list) { 772 if (audit_in_mask(&e->rule, ctx->major) && 773 audit_filter_rules(tsk, &e->rule, ctx, NULL, 774 &state, false)) { 775 rcu_read_unlock(); 776 ctx->current_state = state; 777 return state; 778 } 779 } 780 } 781 rcu_read_unlock(); 782 return AUDIT_BUILD_CONTEXT; 783 } 784 785 /* 786 * Given an audit_name check the inode hash table to see if they match. 787 * Called holding the rcu read lock to protect the use of audit_inode_hash 788 */ 789 static int audit_filter_inode_name(struct task_struct *tsk, 790 struct audit_names *n, 791 struct audit_context *ctx) { 792 int h = audit_hash_ino((u32)n->ino); 793 struct list_head *list = &audit_inode_hash[h]; 794 struct audit_entry *e; 795 enum audit_state state; 796 797 if (list_empty(list)) 798 return 0; 799 800 list_for_each_entry_rcu(e, list, list) { 801 if (audit_in_mask(&e->rule, ctx->major) && 802 audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) { 803 ctx->current_state = state; 804 return 1; 805 } 806 } 807 808 return 0; 809 } 810 811 /* At syscall exit time, this filter is called if any audit_names have been 812 * collected during syscall processing. We only check rules in sublists at hash 813 * buckets applicable to the inode numbers in audit_names. 814 * Regarding audit_state, same rules apply as for audit_filter_syscall(). 815 */ 816 void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx) 817 { 818 struct audit_names *n; 819 820 if (auditd_test_task(tsk)) 821 return; 822 823 rcu_read_lock(); 824 825 list_for_each_entry(n, &ctx->names_list, list) { 826 if (audit_filter_inode_name(tsk, n, ctx)) 827 break; 828 } 829 rcu_read_unlock(); 830 } 831 832 /* Transfer the audit context pointer to the caller, clearing it in the tsk's struct */ 833 static inline struct audit_context *audit_take_context(struct task_struct *tsk, 834 int return_valid, 835 long return_code) 836 { 837 struct audit_context *context = tsk->audit_context; 838 839 if (!context) 840 return NULL; 841 context->return_valid = return_valid; 842 843 /* 844 * we need to fix up the return code in the audit logs if the actual 845 * return codes are later going to be fixed up by the arch specific 846 * signal handlers 847 * 848 * This is actually a test for: 849 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) || 850 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK) 851 * 852 * but is faster than a bunch of || 853 */ 854 if (unlikely(return_code <= -ERESTARTSYS) && 855 (return_code >= -ERESTART_RESTARTBLOCK) && 856 (return_code != -ENOIOCTLCMD)) 857 context->return_code = -EINTR; 858 else 859 context->return_code = return_code; 860 861 if (context->in_syscall && !context->dummy) { 862 audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]); 863 audit_filter_inodes(tsk, context); 864 } 865 866 tsk->audit_context = NULL; 867 return context; 868 } 869 870 static inline void audit_proctitle_free(struct audit_context *context) 871 { 872 kfree(context->proctitle.value); 873 context->proctitle.value = NULL; 874 context->proctitle.len = 0; 875 } 876 877 static inline void audit_free_names(struct audit_context *context) 878 { 879 struct audit_names *n, *next; 880 881 list_for_each_entry_safe(n, next, &context->names_list, list) { 882 list_del(&n->list); 883 if (n->name) 884 putname(n->name); 885 if (n->should_free) 886 kfree(n); 887 } 888 context->name_count = 0; 889 path_put(&context->pwd); 890 context->pwd.dentry = NULL; 891 context->pwd.mnt = NULL; 892 } 893 894 static inline void audit_free_aux(struct audit_context *context) 895 { 896 struct audit_aux_data *aux; 897 898 while ((aux = context->aux)) { 899 context->aux = aux->next; 900 kfree(aux); 901 } 902 while ((aux = context->aux_pids)) { 903 context->aux_pids = aux->next; 904 kfree(aux); 905 } 906 } 907 908 static inline struct audit_context *audit_alloc_context(enum audit_state state) 909 { 910 struct audit_context *context; 911 912 context = kzalloc(sizeof(*context), GFP_KERNEL); 913 if (!context) 914 return NULL; 915 context->state = state; 916 context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 917 INIT_LIST_HEAD(&context->killed_trees); 918 INIT_LIST_HEAD(&context->names_list); 919 return context; 920 } 921 922 /** 923 * audit_alloc - allocate an audit context block for a task 924 * @tsk: task 925 * 926 * Filter on the task information and allocate a per-task audit context 927 * if necessary. Doing so turns on system call auditing for the 928 * specified task. This is called from copy_process, so no lock is 929 * needed. 930 */ 931 int audit_alloc(struct task_struct *tsk) 932 { 933 struct audit_context *context; 934 enum audit_state state; 935 char *key = NULL; 936 937 if (likely(!audit_ever_enabled)) 938 return 0; /* Return if not auditing. */ 939 940 state = audit_filter_task(tsk, &key); 941 if (state == AUDIT_DISABLED) { 942 clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); 943 return 0; 944 } 945 946 if (!(context = audit_alloc_context(state))) { 947 kfree(key); 948 audit_log_lost("out of memory in audit_alloc"); 949 return -ENOMEM; 950 } 951 context->filterkey = key; 952 953 tsk->audit_context = context; 954 set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); 955 return 0; 956 } 957 958 static inline void audit_free_context(struct audit_context *context) 959 { 960 audit_free_names(context); 961 unroll_tree_refs(context, NULL, 0); 962 free_tree_refs(context); 963 audit_free_aux(context); 964 kfree(context->filterkey); 965 kfree(context->sockaddr); 966 audit_proctitle_free(context); 967 kfree(context); 968 } 969 970 static int audit_log_pid_context(struct audit_context *context, pid_t pid, 971 kuid_t auid, kuid_t uid, unsigned int sessionid, 972 u32 sid, char *comm) 973 { 974 struct audit_buffer *ab; 975 char *ctx = NULL; 976 u32 len; 977 int rc = 0; 978 979 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); 980 if (!ab) 981 return rc; 982 983 audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, 984 from_kuid(&init_user_ns, auid), 985 from_kuid(&init_user_ns, uid), sessionid); 986 if (sid) { 987 if (security_secid_to_secctx(sid, &ctx, &len)) { 988 audit_log_format(ab, " obj=(none)"); 989 rc = 1; 990 } else { 991 audit_log_format(ab, " obj=%s", ctx); 992 security_release_secctx(ctx, len); 993 } 994 } 995 audit_log_format(ab, " ocomm="); 996 audit_log_untrustedstring(ab, comm); 997 audit_log_end(ab); 998 999 return rc; 1000 } 1001 1002 static void audit_log_execve_info(struct audit_context *context, 1003 struct audit_buffer **ab) 1004 { 1005 long len_max; 1006 long len_rem; 1007 long len_full; 1008 long len_buf; 1009 long len_abuf = 0; 1010 long len_tmp; 1011 bool require_data; 1012 bool encode; 1013 unsigned int iter; 1014 unsigned int arg; 1015 char *buf_head; 1016 char *buf; 1017 const char __user *p = (const char __user *)current->mm->arg_start; 1018 1019 /* NOTE: this buffer needs to be large enough to hold all the non-arg 1020 * data we put in the audit record for this argument (see the 1021 * code below) ... at this point in time 96 is plenty */ 1022 char abuf[96]; 1023 1024 /* NOTE: we set MAX_EXECVE_AUDIT_LEN to a rather arbitrary limit, the 1025 * current value of 7500 is not as important as the fact that it 1026 * is less than 8k, a setting of 7500 gives us plenty of wiggle 1027 * room if we go over a little bit in the logging below */ 1028 WARN_ON_ONCE(MAX_EXECVE_AUDIT_LEN > 7500); 1029 len_max = MAX_EXECVE_AUDIT_LEN; 1030 1031 /* scratch buffer to hold the userspace args */ 1032 buf_head = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL); 1033 if (!buf_head) { 1034 audit_panic("out of memory for argv string"); 1035 return; 1036 } 1037 buf = buf_head; 1038 1039 audit_log_format(*ab, "argc=%d", context->execve.argc); 1040 1041 len_rem = len_max; 1042 len_buf = 0; 1043 len_full = 0; 1044 require_data = true; 1045 encode = false; 1046 iter = 0; 1047 arg = 0; 1048 do { 1049 /* NOTE: we don't ever want to trust this value for anything 1050 * serious, but the audit record format insists we 1051 * provide an argument length for really long arguments, 1052 * e.g. > MAX_EXECVE_AUDIT_LEN, so we have no choice but 1053 * to use strncpy_from_user() to obtain this value for 1054 * recording in the log, although we don't use it 1055 * anywhere here to avoid a double-fetch problem */ 1056 if (len_full == 0) 1057 len_full = strnlen_user(p, MAX_ARG_STRLEN) - 1; 1058 1059 /* read more data from userspace */ 1060 if (require_data) { 1061 /* can we make more room in the buffer? */ 1062 if (buf != buf_head) { 1063 memmove(buf_head, buf, len_buf); 1064 buf = buf_head; 1065 } 1066 1067 /* fetch as much as we can of the argument */ 1068 len_tmp = strncpy_from_user(&buf_head[len_buf], p, 1069 len_max - len_buf); 1070 if (len_tmp == -EFAULT) { 1071 /* unable to copy from userspace */ 1072 send_sig(SIGKILL, current, 0); 1073 goto out; 1074 } else if (len_tmp == (len_max - len_buf)) { 1075 /* buffer is not large enough */ 1076 require_data = true; 1077 /* NOTE: if we are going to span multiple 1078 * buffers force the encoding so we stand 1079 * a chance at a sane len_full value and 1080 * consistent record encoding */ 1081 encode = true; 1082 len_full = len_full * 2; 1083 p += len_tmp; 1084 } else { 1085 require_data = false; 1086 if (!encode) 1087 encode = audit_string_contains_control( 1088 buf, len_tmp); 1089 /* try to use a trusted value for len_full */ 1090 if (len_full < len_max) 1091 len_full = (encode ? 1092 len_tmp * 2 : len_tmp); 1093 p += len_tmp + 1; 1094 } 1095 len_buf += len_tmp; 1096 buf_head[len_buf] = '\0'; 1097 1098 /* length of the buffer in the audit record? */ 1099 len_abuf = (encode ? len_buf * 2 : len_buf + 2); 1100 } 1101 1102 /* write as much as we can to the audit log */ 1103 if (len_buf > 0) { 1104 /* NOTE: some magic numbers here - basically if we 1105 * can't fit a reasonable amount of data into the 1106 * existing audit buffer, flush it and start with 1107 * a new buffer */ 1108 if ((sizeof(abuf) + 8) > len_rem) { 1109 len_rem = len_max; 1110 audit_log_end(*ab); 1111 *ab = audit_log_start(context, 1112 GFP_KERNEL, AUDIT_EXECVE); 1113 if (!*ab) 1114 goto out; 1115 } 1116 1117 /* create the non-arg portion of the arg record */ 1118 len_tmp = 0; 1119 if (require_data || (iter > 0) || 1120 ((len_abuf + sizeof(abuf)) > len_rem)) { 1121 if (iter == 0) { 1122 len_tmp += snprintf(&abuf[len_tmp], 1123 sizeof(abuf) - len_tmp, 1124 " a%d_len=%lu", 1125 arg, len_full); 1126 } 1127 len_tmp += snprintf(&abuf[len_tmp], 1128 sizeof(abuf) - len_tmp, 1129 " a%d[%d]=", arg, iter++); 1130 } else 1131 len_tmp += snprintf(&abuf[len_tmp], 1132 sizeof(abuf) - len_tmp, 1133 " a%d=", arg); 1134 WARN_ON(len_tmp >= sizeof(abuf)); 1135 abuf[sizeof(abuf) - 1] = '\0'; 1136 1137 /* log the arg in the audit record */ 1138 audit_log_format(*ab, "%s", abuf); 1139 len_rem -= len_tmp; 1140 len_tmp = len_buf; 1141 if (encode) { 1142 if (len_abuf > len_rem) 1143 len_tmp = len_rem / 2; /* encoding */ 1144 audit_log_n_hex(*ab, buf, len_tmp); 1145 len_rem -= len_tmp * 2; 1146 len_abuf -= len_tmp * 2; 1147 } else { 1148 if (len_abuf > len_rem) 1149 len_tmp = len_rem - 2; /* quotes */ 1150 audit_log_n_string(*ab, buf, len_tmp); 1151 len_rem -= len_tmp + 2; 1152 /* don't subtract the "2" because we still need 1153 * to add quotes to the remaining string */ 1154 len_abuf -= len_tmp; 1155 } 1156 len_buf -= len_tmp; 1157 buf += len_tmp; 1158 } 1159 1160 /* ready to move to the next argument? */ 1161 if ((len_buf == 0) && !require_data) { 1162 arg++; 1163 iter = 0; 1164 len_full = 0; 1165 require_data = true; 1166 encode = false; 1167 } 1168 } while (arg < context->execve.argc); 1169 1170 /* NOTE: the caller handles the final audit_log_end() call */ 1171 1172 out: 1173 kfree(buf_head); 1174 } 1175 1176 static void show_special(struct audit_context *context, int *call_panic) 1177 { 1178 struct audit_buffer *ab; 1179 int i; 1180 1181 ab = audit_log_start(context, GFP_KERNEL, context->type); 1182 if (!ab) 1183 return; 1184 1185 switch (context->type) { 1186 case AUDIT_SOCKETCALL: { 1187 int nargs = context->socketcall.nargs; 1188 audit_log_format(ab, "nargs=%d", nargs); 1189 for (i = 0; i < nargs; i++) 1190 audit_log_format(ab, " a%d=%lx", i, 1191 context->socketcall.args[i]); 1192 break; } 1193 case AUDIT_IPC: { 1194 u32 osid = context->ipc.osid; 1195 1196 audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho", 1197 from_kuid(&init_user_ns, context->ipc.uid), 1198 from_kgid(&init_user_ns, context->ipc.gid), 1199 context->ipc.mode); 1200 if (osid) { 1201 char *ctx = NULL; 1202 u32 len; 1203 if (security_secid_to_secctx(osid, &ctx, &len)) { 1204 audit_log_format(ab, " osid=%u", osid); 1205 *call_panic = 1; 1206 } else { 1207 audit_log_format(ab, " obj=%s", ctx); 1208 security_release_secctx(ctx, len); 1209 } 1210 } 1211 if (context->ipc.has_perm) { 1212 audit_log_end(ab); 1213 ab = audit_log_start(context, GFP_KERNEL, 1214 AUDIT_IPC_SET_PERM); 1215 if (unlikely(!ab)) 1216 return; 1217 audit_log_format(ab, 1218 "qbytes=%lx ouid=%u ogid=%u mode=%#ho", 1219 context->ipc.qbytes, 1220 context->ipc.perm_uid, 1221 context->ipc.perm_gid, 1222 context->ipc.perm_mode); 1223 } 1224 break; } 1225 case AUDIT_MQ_OPEN: 1226 audit_log_format(ab, 1227 "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld " 1228 "mq_msgsize=%ld mq_curmsgs=%ld", 1229 context->mq_open.oflag, context->mq_open.mode, 1230 context->mq_open.attr.mq_flags, 1231 context->mq_open.attr.mq_maxmsg, 1232 context->mq_open.attr.mq_msgsize, 1233 context->mq_open.attr.mq_curmsgs); 1234 break; 1235 case AUDIT_MQ_SENDRECV: 1236 audit_log_format(ab, 1237 "mqdes=%d msg_len=%zd msg_prio=%u " 1238 "abs_timeout_sec=%lld abs_timeout_nsec=%ld", 1239 context->mq_sendrecv.mqdes, 1240 context->mq_sendrecv.msg_len, 1241 context->mq_sendrecv.msg_prio, 1242 (long long) context->mq_sendrecv.abs_timeout.tv_sec, 1243 context->mq_sendrecv.abs_timeout.tv_nsec); 1244 break; 1245 case AUDIT_MQ_NOTIFY: 1246 audit_log_format(ab, "mqdes=%d sigev_signo=%d", 1247 context->mq_notify.mqdes, 1248 context->mq_notify.sigev_signo); 1249 break; 1250 case AUDIT_MQ_GETSETATTR: { 1251 struct mq_attr *attr = &context->mq_getsetattr.mqstat; 1252 audit_log_format(ab, 1253 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld " 1254 "mq_curmsgs=%ld ", 1255 context->mq_getsetattr.mqdes, 1256 attr->mq_flags, attr->mq_maxmsg, 1257 attr->mq_msgsize, attr->mq_curmsgs); 1258 break; } 1259 case AUDIT_CAPSET: 1260 audit_log_format(ab, "pid=%d", context->capset.pid); 1261 audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable); 1262 audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted); 1263 audit_log_cap(ab, "cap_pe", &context->capset.cap.effective); 1264 audit_log_cap(ab, "cap_pa", &context->capset.cap.ambient); 1265 break; 1266 case AUDIT_MMAP: 1267 audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd, 1268 context->mmap.flags); 1269 break; 1270 case AUDIT_EXECVE: 1271 audit_log_execve_info(context, &ab); 1272 break; 1273 case AUDIT_KERN_MODULE: 1274 audit_log_format(ab, "name="); 1275 audit_log_untrustedstring(ab, context->module.name); 1276 kfree(context->module.name); 1277 break; 1278 } 1279 audit_log_end(ab); 1280 } 1281 1282 static inline int audit_proctitle_rtrim(char *proctitle, int len) 1283 { 1284 char *end = proctitle + len - 1; 1285 while (end > proctitle && !isprint(*end)) 1286 end--; 1287 1288 /* catch the case where proctitle is only 1 non-print character */ 1289 len = end - proctitle + 1; 1290 len -= isprint(proctitle[len-1]) == 0; 1291 return len; 1292 } 1293 1294 static void audit_log_proctitle(struct task_struct *tsk, 1295 struct audit_context *context) 1296 { 1297 int res; 1298 char *buf; 1299 char *msg = "(null)"; 1300 int len = strlen(msg); 1301 struct audit_buffer *ab; 1302 1303 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE); 1304 if (!ab) 1305 return; /* audit_panic or being filtered */ 1306 1307 audit_log_format(ab, "proctitle="); 1308 1309 /* Not cached */ 1310 if (!context->proctitle.value) { 1311 buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL); 1312 if (!buf) 1313 goto out; 1314 /* Historically called this from procfs naming */ 1315 res = get_cmdline(tsk, buf, MAX_PROCTITLE_AUDIT_LEN); 1316 if (res == 0) { 1317 kfree(buf); 1318 goto out; 1319 } 1320 res = audit_proctitle_rtrim(buf, res); 1321 if (res == 0) { 1322 kfree(buf); 1323 goto out; 1324 } 1325 context->proctitle.value = buf; 1326 context->proctitle.len = res; 1327 } 1328 msg = context->proctitle.value; 1329 len = context->proctitle.len; 1330 out: 1331 audit_log_n_untrustedstring(ab, msg, len); 1332 audit_log_end(ab); 1333 } 1334 1335 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk) 1336 { 1337 int i, call_panic = 0; 1338 struct audit_buffer *ab; 1339 struct audit_aux_data *aux; 1340 struct audit_names *n; 1341 1342 /* tsk == current */ 1343 context->personality = tsk->personality; 1344 1345 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); 1346 if (!ab) 1347 return; /* audit_panic has been called */ 1348 audit_log_format(ab, "arch=%x syscall=%d", 1349 context->arch, context->major); 1350 if (context->personality != PER_LINUX) 1351 audit_log_format(ab, " per=%lx", context->personality); 1352 if (context->return_valid) 1353 audit_log_format(ab, " success=%s exit=%ld", 1354 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", 1355 context->return_code); 1356 1357 audit_log_format(ab, 1358 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d", 1359 context->argv[0], 1360 context->argv[1], 1361 context->argv[2], 1362 context->argv[3], 1363 context->name_count); 1364 1365 audit_log_task_info(ab, tsk); 1366 audit_log_key(ab, context->filterkey); 1367 audit_log_end(ab); 1368 1369 for (aux = context->aux; aux; aux = aux->next) { 1370 1371 ab = audit_log_start(context, GFP_KERNEL, aux->type); 1372 if (!ab) 1373 continue; /* audit_panic has been called */ 1374 1375 switch (aux->type) { 1376 1377 case AUDIT_BPRM_FCAPS: { 1378 struct audit_aux_data_bprm_fcaps *axs = (void *)aux; 1379 audit_log_format(ab, "fver=%x", axs->fcap_ver); 1380 audit_log_cap(ab, "fp", &axs->fcap.permitted); 1381 audit_log_cap(ab, "fi", &axs->fcap.inheritable); 1382 audit_log_format(ab, " fe=%d", axs->fcap.fE); 1383 audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted); 1384 audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable); 1385 audit_log_cap(ab, "old_pe", &axs->old_pcap.effective); 1386 audit_log_cap(ab, "old_pa", &axs->old_pcap.ambient); 1387 audit_log_cap(ab, "pp", &axs->new_pcap.permitted); 1388 audit_log_cap(ab, "pi", &axs->new_pcap.inheritable); 1389 audit_log_cap(ab, "pe", &axs->new_pcap.effective); 1390 audit_log_cap(ab, "pa", &axs->new_pcap.ambient); 1391 break; } 1392 1393 } 1394 audit_log_end(ab); 1395 } 1396 1397 if (context->type) 1398 show_special(context, &call_panic); 1399 1400 if (context->fds[0] >= 0) { 1401 ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR); 1402 if (ab) { 1403 audit_log_format(ab, "fd0=%d fd1=%d", 1404 context->fds[0], context->fds[1]); 1405 audit_log_end(ab); 1406 } 1407 } 1408 1409 if (context->sockaddr_len) { 1410 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR); 1411 if (ab) { 1412 audit_log_format(ab, "saddr="); 1413 audit_log_n_hex(ab, (void *)context->sockaddr, 1414 context->sockaddr_len); 1415 audit_log_end(ab); 1416 } 1417 } 1418 1419 for (aux = context->aux_pids; aux; aux = aux->next) { 1420 struct audit_aux_data_pids *axs = (void *)aux; 1421 1422 for (i = 0; i < axs->pid_count; i++) 1423 if (audit_log_pid_context(context, axs->target_pid[i], 1424 axs->target_auid[i], 1425 axs->target_uid[i], 1426 axs->target_sessionid[i], 1427 axs->target_sid[i], 1428 axs->target_comm[i])) 1429 call_panic = 1; 1430 } 1431 1432 if (context->target_pid && 1433 audit_log_pid_context(context, context->target_pid, 1434 context->target_auid, context->target_uid, 1435 context->target_sessionid, 1436 context->target_sid, context->target_comm)) 1437 call_panic = 1; 1438 1439 if (context->pwd.dentry && context->pwd.mnt) { 1440 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); 1441 if (ab) { 1442 audit_log_d_path(ab, "cwd=", &context->pwd); 1443 audit_log_end(ab); 1444 } 1445 } 1446 1447 i = 0; 1448 list_for_each_entry(n, &context->names_list, list) { 1449 if (n->hidden) 1450 continue; 1451 audit_log_name(context, n, NULL, i++, &call_panic); 1452 } 1453 1454 audit_log_proctitle(tsk, context); 1455 1456 /* Send end of event record to help user space know we are finished */ 1457 ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); 1458 if (ab) 1459 audit_log_end(ab); 1460 if (call_panic) 1461 audit_panic("error converting sid to string"); 1462 } 1463 1464 /** 1465 * __audit_free - free a per-task audit context 1466 * @tsk: task whose audit context block to free 1467 * 1468 * Called from copy_process and do_exit 1469 */ 1470 void __audit_free(struct task_struct *tsk) 1471 { 1472 struct audit_context *context; 1473 1474 context = audit_take_context(tsk, 0, 0); 1475 if (!context) 1476 return; 1477 1478 /* Check for system calls that do not go through the exit 1479 * function (e.g., exit_group), then free context block. 1480 * We use GFP_ATOMIC here because we might be doing this 1481 * in the context of the idle thread */ 1482 /* that can happen only if we are called from do_exit() */ 1483 if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) 1484 audit_log_exit(context, tsk); 1485 if (!list_empty(&context->killed_trees)) 1486 audit_kill_trees(&context->killed_trees); 1487 1488 audit_free_context(context); 1489 } 1490 1491 /** 1492 * __audit_syscall_entry - fill in an audit record at syscall entry 1493 * @major: major syscall type (function) 1494 * @a1: additional syscall register 1 1495 * @a2: additional syscall register 2 1496 * @a3: additional syscall register 3 1497 * @a4: additional syscall register 4 1498 * 1499 * Fill in audit context at syscall entry. This only happens if the 1500 * audit context was created when the task was created and the state or 1501 * filters demand the audit context be built. If the state from the 1502 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, 1503 * then the record will be written at syscall exit time (otherwise, it 1504 * will only be written if another part of the kernel requests that it 1505 * be written). 1506 */ 1507 void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2, 1508 unsigned long a3, unsigned long a4) 1509 { 1510 struct task_struct *tsk = current; 1511 struct audit_context *context = tsk->audit_context; 1512 enum audit_state state; 1513 1514 if (!context) 1515 return; 1516 1517 BUG_ON(context->in_syscall || context->name_count); 1518 1519 if (!audit_enabled) 1520 return; 1521 1522 context->arch = syscall_get_arch(); 1523 context->major = major; 1524 context->argv[0] = a1; 1525 context->argv[1] = a2; 1526 context->argv[2] = a3; 1527 context->argv[3] = a4; 1528 1529 state = context->state; 1530 context->dummy = !audit_n_rules; 1531 if (!context->dummy && state == AUDIT_BUILD_CONTEXT) { 1532 context->prio = 0; 1533 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]); 1534 } 1535 if (state == AUDIT_DISABLED) 1536 return; 1537 1538 context->serial = 0; 1539 context->ctime = current_kernel_time64(); 1540 context->in_syscall = 1; 1541 context->current_state = state; 1542 context->ppid = 0; 1543 } 1544 1545 /** 1546 * __audit_syscall_exit - deallocate audit context after a system call 1547 * @success: success value of the syscall 1548 * @return_code: return value of the syscall 1549 * 1550 * Tear down after system call. If the audit context has been marked as 1551 * auditable (either because of the AUDIT_RECORD_CONTEXT state from 1552 * filtering, or because some other part of the kernel wrote an audit 1553 * message), then write out the syscall information. In call cases, 1554 * free the names stored from getname(). 1555 */ 1556 void __audit_syscall_exit(int success, long return_code) 1557 { 1558 struct task_struct *tsk = current; 1559 struct audit_context *context; 1560 1561 if (success) 1562 success = AUDITSC_SUCCESS; 1563 else 1564 success = AUDITSC_FAILURE; 1565 1566 context = audit_take_context(tsk, success, return_code); 1567 if (!context) 1568 return; 1569 1570 if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) 1571 audit_log_exit(context, tsk); 1572 1573 context->in_syscall = 0; 1574 context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; 1575 1576 if (!list_empty(&context->killed_trees)) 1577 audit_kill_trees(&context->killed_trees); 1578 1579 audit_free_names(context); 1580 unroll_tree_refs(context, NULL, 0); 1581 audit_free_aux(context); 1582 context->aux = NULL; 1583 context->aux_pids = NULL; 1584 context->target_pid = 0; 1585 context->target_sid = 0; 1586 context->sockaddr_len = 0; 1587 context->type = 0; 1588 context->fds[0] = -1; 1589 if (context->state != AUDIT_RECORD_CONTEXT) { 1590 kfree(context->filterkey); 1591 context->filterkey = NULL; 1592 } 1593 tsk->audit_context = context; 1594 } 1595 1596 static inline void handle_one(const struct inode *inode) 1597 { 1598 #ifdef CONFIG_AUDIT_TREE 1599 struct audit_context *context; 1600 struct audit_tree_refs *p; 1601 struct audit_chunk *chunk; 1602 int count; 1603 if (likely(!inode->i_fsnotify_marks)) 1604 return; 1605 context = current->audit_context; 1606 p = context->trees; 1607 count = context->tree_count; 1608 rcu_read_lock(); 1609 chunk = audit_tree_lookup(inode); 1610 rcu_read_unlock(); 1611 if (!chunk) 1612 return; 1613 if (likely(put_tree_ref(context, chunk))) 1614 return; 1615 if (unlikely(!grow_tree_refs(context))) { 1616 pr_warn("out of memory, audit has lost a tree reference\n"); 1617 audit_set_auditable(context); 1618 audit_put_chunk(chunk); 1619 unroll_tree_refs(context, p, count); 1620 return; 1621 } 1622 put_tree_ref(context, chunk); 1623 #endif 1624 } 1625 1626 static void handle_path(const struct dentry *dentry) 1627 { 1628 #ifdef CONFIG_AUDIT_TREE 1629 struct audit_context *context; 1630 struct audit_tree_refs *p; 1631 const struct dentry *d, *parent; 1632 struct audit_chunk *drop; 1633 unsigned long seq; 1634 int count; 1635 1636 context = current->audit_context; 1637 p = context->trees; 1638 count = context->tree_count; 1639 retry: 1640 drop = NULL; 1641 d = dentry; 1642 rcu_read_lock(); 1643 seq = read_seqbegin(&rename_lock); 1644 for(;;) { 1645 struct inode *inode = d_backing_inode(d); 1646 if (inode && unlikely(inode->i_fsnotify_marks)) { 1647 struct audit_chunk *chunk; 1648 chunk = audit_tree_lookup(inode); 1649 if (chunk) { 1650 if (unlikely(!put_tree_ref(context, chunk))) { 1651 drop = chunk; 1652 break; 1653 } 1654 } 1655 } 1656 parent = d->d_parent; 1657 if (parent == d) 1658 break; 1659 d = parent; 1660 } 1661 if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */ 1662 rcu_read_unlock(); 1663 if (!drop) { 1664 /* just a race with rename */ 1665 unroll_tree_refs(context, p, count); 1666 goto retry; 1667 } 1668 audit_put_chunk(drop); 1669 if (grow_tree_refs(context)) { 1670 /* OK, got more space */ 1671 unroll_tree_refs(context, p, count); 1672 goto retry; 1673 } 1674 /* too bad */ 1675 pr_warn("out of memory, audit has lost a tree reference\n"); 1676 unroll_tree_refs(context, p, count); 1677 audit_set_auditable(context); 1678 return; 1679 } 1680 rcu_read_unlock(); 1681 #endif 1682 } 1683 1684 static struct audit_names *audit_alloc_name(struct audit_context *context, 1685 unsigned char type) 1686 { 1687 struct audit_names *aname; 1688 1689 if (context->name_count < AUDIT_NAMES) { 1690 aname = &context->preallocated_names[context->name_count]; 1691 memset(aname, 0, sizeof(*aname)); 1692 } else { 1693 aname = kzalloc(sizeof(*aname), GFP_NOFS); 1694 if (!aname) 1695 return NULL; 1696 aname->should_free = true; 1697 } 1698 1699 aname->ino = AUDIT_INO_UNSET; 1700 aname->type = type; 1701 list_add_tail(&aname->list, &context->names_list); 1702 1703 context->name_count++; 1704 return aname; 1705 } 1706 1707 /** 1708 * __audit_reusename - fill out filename with info from existing entry 1709 * @uptr: userland ptr to pathname 1710 * 1711 * Search the audit_names list for the current audit context. If there is an 1712 * existing entry with a matching "uptr" then return the filename 1713 * associated with that audit_name. If not, return NULL. 1714 */ 1715 struct filename * 1716 __audit_reusename(const __user char *uptr) 1717 { 1718 struct audit_context *context = current->audit_context; 1719 struct audit_names *n; 1720 1721 list_for_each_entry(n, &context->names_list, list) { 1722 if (!n->name) 1723 continue; 1724 if (n->name->uptr == uptr) { 1725 n->name->refcnt++; 1726 return n->name; 1727 } 1728 } 1729 return NULL; 1730 } 1731 1732 /** 1733 * __audit_getname - add a name to the list 1734 * @name: name to add 1735 * 1736 * Add a name to the list of audit names for this context. 1737 * Called from fs/namei.c:getname(). 1738 */ 1739 void __audit_getname(struct filename *name) 1740 { 1741 struct audit_context *context = current->audit_context; 1742 struct audit_names *n; 1743 1744 if (!context->in_syscall) 1745 return; 1746 1747 n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); 1748 if (!n) 1749 return; 1750 1751 n->name = name; 1752 n->name_len = AUDIT_NAME_FULL; 1753 name->aname = n; 1754 name->refcnt++; 1755 1756 if (!context->pwd.dentry) 1757 get_fs_pwd(current->fs, &context->pwd); 1758 } 1759 1760 /** 1761 * __audit_inode - store the inode and device from a lookup 1762 * @name: name being audited 1763 * @dentry: dentry being audited 1764 * @flags: attributes for this particular entry 1765 */ 1766 void __audit_inode(struct filename *name, const struct dentry *dentry, 1767 unsigned int flags) 1768 { 1769 struct audit_context *context = current->audit_context; 1770 struct inode *inode = d_backing_inode(dentry); 1771 struct audit_names *n; 1772 bool parent = flags & AUDIT_INODE_PARENT; 1773 1774 if (!context->in_syscall) 1775 return; 1776 1777 if (!name) 1778 goto out_alloc; 1779 1780 /* 1781 * If we have a pointer to an audit_names entry already, then we can 1782 * just use it directly if the type is correct. 1783 */ 1784 n = name->aname; 1785 if (n) { 1786 if (parent) { 1787 if (n->type == AUDIT_TYPE_PARENT || 1788 n->type == AUDIT_TYPE_UNKNOWN) 1789 goto out; 1790 } else { 1791 if (n->type != AUDIT_TYPE_PARENT) 1792 goto out; 1793 } 1794 } 1795 1796 list_for_each_entry_reverse(n, &context->names_list, list) { 1797 if (n->ino) { 1798 /* valid inode number, use that for the comparison */ 1799 if (n->ino != inode->i_ino || 1800 n->dev != inode->i_sb->s_dev) 1801 continue; 1802 } else if (n->name) { 1803 /* inode number has not been set, check the name */ 1804 if (strcmp(n->name->name, name->name)) 1805 continue; 1806 } else 1807 /* no inode and no name (?!) ... this is odd ... */ 1808 continue; 1809 1810 /* match the correct record type */ 1811 if (parent) { 1812 if (n->type == AUDIT_TYPE_PARENT || 1813 n->type == AUDIT_TYPE_UNKNOWN) 1814 goto out; 1815 } else { 1816 if (n->type != AUDIT_TYPE_PARENT) 1817 goto out; 1818 } 1819 } 1820 1821 out_alloc: 1822 /* unable to find an entry with both a matching name and type */ 1823 n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); 1824 if (!n) 1825 return; 1826 if (name) { 1827 n->name = name; 1828 name->refcnt++; 1829 } 1830 1831 out: 1832 if (parent) { 1833 n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL; 1834 n->type = AUDIT_TYPE_PARENT; 1835 if (flags & AUDIT_INODE_HIDDEN) 1836 n->hidden = true; 1837 } else { 1838 n->name_len = AUDIT_NAME_FULL; 1839 n->type = AUDIT_TYPE_NORMAL; 1840 } 1841 handle_path(dentry); 1842 audit_copy_inode(n, dentry, inode); 1843 } 1844 1845 void __audit_file(const struct file *file) 1846 { 1847 __audit_inode(NULL, file->f_path.dentry, 0); 1848 } 1849 1850 /** 1851 * __audit_inode_child - collect inode info for created/removed objects 1852 * @parent: inode of dentry parent 1853 * @dentry: dentry being audited 1854 * @type: AUDIT_TYPE_* value that we're looking for 1855 * 1856 * For syscalls that create or remove filesystem objects, audit_inode 1857 * can only collect information for the filesystem object's parent. 1858 * This call updates the audit context with the child's information. 1859 * Syscalls that create a new filesystem object must be hooked after 1860 * the object is created. Syscalls that remove a filesystem object 1861 * must be hooked prior, in order to capture the target inode during 1862 * unsuccessful attempts. 1863 */ 1864 void __audit_inode_child(struct inode *parent, 1865 const struct dentry *dentry, 1866 const unsigned char type) 1867 { 1868 struct audit_context *context = current->audit_context; 1869 struct inode *inode = d_backing_inode(dentry); 1870 const char *dname = dentry->d_name.name; 1871 struct audit_names *n, *found_parent = NULL, *found_child = NULL; 1872 struct audit_entry *e; 1873 struct list_head *list = &audit_filter_list[AUDIT_FILTER_FS]; 1874 int i; 1875 1876 if (!context->in_syscall) 1877 return; 1878 1879 rcu_read_lock(); 1880 if (!list_empty(list)) { 1881 list_for_each_entry_rcu(e, list, list) { 1882 for (i = 0; i < e->rule.field_count; i++) { 1883 struct audit_field *f = &e->rule.fields[i]; 1884 1885 if (f->type == AUDIT_FSTYPE) { 1886 if (audit_comparator(parent->i_sb->s_magic, 1887 f->op, f->val)) { 1888 if (e->rule.action == AUDIT_NEVER) { 1889 rcu_read_unlock(); 1890 return; 1891 } 1892 } 1893 } 1894 } 1895 } 1896 } 1897 rcu_read_unlock(); 1898 1899 if (inode) 1900 handle_one(inode); 1901 1902 /* look for a parent entry first */ 1903 list_for_each_entry(n, &context->names_list, list) { 1904 if (!n->name || 1905 (n->type != AUDIT_TYPE_PARENT && 1906 n->type != AUDIT_TYPE_UNKNOWN)) 1907 continue; 1908 1909 if (n->ino == parent->i_ino && n->dev == parent->i_sb->s_dev && 1910 !audit_compare_dname_path(dname, 1911 n->name->name, n->name_len)) { 1912 if (n->type == AUDIT_TYPE_UNKNOWN) 1913 n->type = AUDIT_TYPE_PARENT; 1914 found_parent = n; 1915 break; 1916 } 1917 } 1918 1919 /* is there a matching child entry? */ 1920 list_for_each_entry(n, &context->names_list, list) { 1921 /* can only match entries that have a name */ 1922 if (!n->name || 1923 (n->type != type && n->type != AUDIT_TYPE_UNKNOWN)) 1924 continue; 1925 1926 if (!strcmp(dname, n->name->name) || 1927 !audit_compare_dname_path(dname, n->name->name, 1928 found_parent ? 1929 found_parent->name_len : 1930 AUDIT_NAME_FULL)) { 1931 if (n->type == AUDIT_TYPE_UNKNOWN) 1932 n->type = type; 1933 found_child = n; 1934 break; 1935 } 1936 } 1937 1938 if (!found_parent) { 1939 /* create a new, "anonymous" parent record */ 1940 n = audit_alloc_name(context, AUDIT_TYPE_PARENT); 1941 if (!n) 1942 return; 1943 audit_copy_inode(n, NULL, parent); 1944 } 1945 1946 if (!found_child) { 1947 found_child = audit_alloc_name(context, type); 1948 if (!found_child) 1949 return; 1950 1951 /* Re-use the name belonging to the slot for a matching parent 1952 * directory. All names for this context are relinquished in 1953 * audit_free_names() */ 1954 if (found_parent) { 1955 found_child->name = found_parent->name; 1956 found_child->name_len = AUDIT_NAME_FULL; 1957 found_child->name->refcnt++; 1958 } 1959 } 1960 1961 if (inode) 1962 audit_copy_inode(found_child, dentry, inode); 1963 else 1964 found_child->ino = AUDIT_INO_UNSET; 1965 } 1966 EXPORT_SYMBOL_GPL(__audit_inode_child); 1967 1968 /** 1969 * auditsc_get_stamp - get local copies of audit_context values 1970 * @ctx: audit_context for the task 1971 * @t: timespec64 to store time recorded in the audit_context 1972 * @serial: serial value that is recorded in the audit_context 1973 * 1974 * Also sets the context as auditable. 1975 */ 1976 int auditsc_get_stamp(struct audit_context *ctx, 1977 struct timespec64 *t, unsigned int *serial) 1978 { 1979 if (!ctx->in_syscall) 1980 return 0; 1981 if (!ctx->serial) 1982 ctx->serial = audit_serial(); 1983 t->tv_sec = ctx->ctime.tv_sec; 1984 t->tv_nsec = ctx->ctime.tv_nsec; 1985 *serial = ctx->serial; 1986 if (!ctx->prio) { 1987 ctx->prio = 1; 1988 ctx->current_state = AUDIT_RECORD_CONTEXT; 1989 } 1990 return 1; 1991 } 1992 1993 /* global counter which is incremented every time something logs in */ 1994 static atomic_t session_id = ATOMIC_INIT(0); 1995 1996 static int audit_set_loginuid_perm(kuid_t loginuid) 1997 { 1998 /* if we are unset, we don't need privs */ 1999 if (!audit_loginuid_set(current)) 2000 return 0; 2001 /* if AUDIT_FEATURE_LOGINUID_IMMUTABLE means never ever allow a change*/ 2002 if (is_audit_feature_set(AUDIT_FEATURE_LOGINUID_IMMUTABLE)) 2003 return -EPERM; 2004 /* it is set, you need permission */ 2005 if (!capable(CAP_AUDIT_CONTROL)) 2006 return -EPERM; 2007 /* reject if this is not an unset and we don't allow that */ 2008 if (is_audit_feature_set(AUDIT_FEATURE_ONLY_UNSET_LOGINUID) && uid_valid(loginuid)) 2009 return -EPERM; 2010 return 0; 2011 } 2012 2013 static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid, 2014 unsigned int oldsessionid, unsigned int sessionid, 2015 int rc) 2016 { 2017 struct audit_buffer *ab; 2018 uid_t uid, oldloginuid, loginuid; 2019 struct tty_struct *tty; 2020 2021 if (!audit_enabled) 2022 return; 2023 2024 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); 2025 if (!ab) 2026 return; 2027 2028 uid = from_kuid(&init_user_ns, task_uid(current)); 2029 oldloginuid = from_kuid(&init_user_ns, koldloginuid); 2030 loginuid = from_kuid(&init_user_ns, kloginuid), 2031 tty = audit_get_tty(current); 2032 2033 audit_log_format(ab, "pid=%d uid=%u", task_tgid_nr(current), uid); 2034 audit_log_task_context(ab); 2035 audit_log_format(ab, " old-auid=%u auid=%u tty=%s old-ses=%u ses=%u res=%d", 2036 oldloginuid, loginuid, tty ? tty_name(tty) : "(none)", 2037 oldsessionid, sessionid, !rc); 2038 audit_put_tty(tty); 2039 audit_log_end(ab); 2040 } 2041 2042 /** 2043 * audit_set_loginuid - set current task's audit_context loginuid 2044 * @loginuid: loginuid value 2045 * 2046 * Returns 0. 2047 * 2048 * Called (set) from fs/proc/base.c::proc_loginuid_write(). 2049 */ 2050 int audit_set_loginuid(kuid_t loginuid) 2051 { 2052 struct task_struct *task = current; 2053 unsigned int oldsessionid, sessionid = (unsigned int)-1; 2054 kuid_t oldloginuid; 2055 int rc; 2056 2057 oldloginuid = audit_get_loginuid(current); 2058 oldsessionid = audit_get_sessionid(current); 2059 2060 rc = audit_set_loginuid_perm(loginuid); 2061 if (rc) 2062 goto out; 2063 2064 /* are we setting or clearing? */ 2065 if (uid_valid(loginuid)) { 2066 sessionid = (unsigned int)atomic_inc_return(&session_id); 2067 if (unlikely(sessionid == (unsigned int)-1)) 2068 sessionid = (unsigned int)atomic_inc_return(&session_id); 2069 } 2070 2071 task->sessionid = sessionid; 2072 task->loginuid = loginuid; 2073 out: 2074 audit_log_set_loginuid(oldloginuid, loginuid, oldsessionid, sessionid, rc); 2075 return rc; 2076 } 2077 2078 /** 2079 * __audit_mq_open - record audit data for a POSIX MQ open 2080 * @oflag: open flag 2081 * @mode: mode bits 2082 * @attr: queue attributes 2083 * 2084 */ 2085 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr) 2086 { 2087 struct audit_context *context = current->audit_context; 2088 2089 if (attr) 2090 memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr)); 2091 else 2092 memset(&context->mq_open.attr, 0, sizeof(struct mq_attr)); 2093 2094 context->mq_open.oflag = oflag; 2095 context->mq_open.mode = mode; 2096 2097 context->type = AUDIT_MQ_OPEN; 2098 } 2099 2100 /** 2101 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive 2102 * @mqdes: MQ descriptor 2103 * @msg_len: Message length 2104 * @msg_prio: Message priority 2105 * @abs_timeout: Message timeout in absolute time 2106 * 2107 */ 2108 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, 2109 const struct timespec64 *abs_timeout) 2110 { 2111 struct audit_context *context = current->audit_context; 2112 struct timespec64 *p = &context->mq_sendrecv.abs_timeout; 2113 2114 if (abs_timeout) 2115 memcpy(p, abs_timeout, sizeof(*p)); 2116 else 2117 memset(p, 0, sizeof(*p)); 2118 2119 context->mq_sendrecv.mqdes = mqdes; 2120 context->mq_sendrecv.msg_len = msg_len; 2121 context->mq_sendrecv.msg_prio = msg_prio; 2122 2123 context->type = AUDIT_MQ_SENDRECV; 2124 } 2125 2126 /** 2127 * __audit_mq_notify - record audit data for a POSIX MQ notify 2128 * @mqdes: MQ descriptor 2129 * @notification: Notification event 2130 * 2131 */ 2132 2133 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification) 2134 { 2135 struct audit_context *context = current->audit_context; 2136 2137 if (notification) 2138 context->mq_notify.sigev_signo = notification->sigev_signo; 2139 else 2140 context->mq_notify.sigev_signo = 0; 2141 2142 context->mq_notify.mqdes = mqdes; 2143 context->type = AUDIT_MQ_NOTIFY; 2144 } 2145 2146 /** 2147 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute 2148 * @mqdes: MQ descriptor 2149 * @mqstat: MQ flags 2150 * 2151 */ 2152 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) 2153 { 2154 struct audit_context *context = current->audit_context; 2155 context->mq_getsetattr.mqdes = mqdes; 2156 context->mq_getsetattr.mqstat = *mqstat; 2157 context->type = AUDIT_MQ_GETSETATTR; 2158 } 2159 2160 /** 2161 * __audit_ipc_obj - record audit data for ipc object 2162 * @ipcp: ipc permissions 2163 * 2164 */ 2165 void __audit_ipc_obj(struct kern_ipc_perm *ipcp) 2166 { 2167 struct audit_context *context = current->audit_context; 2168 context->ipc.uid = ipcp->uid; 2169 context->ipc.gid = ipcp->gid; 2170 context->ipc.mode = ipcp->mode; 2171 context->ipc.has_perm = 0; 2172 security_ipc_getsecid(ipcp, &context->ipc.osid); 2173 context->type = AUDIT_IPC; 2174 } 2175 2176 /** 2177 * __audit_ipc_set_perm - record audit data for new ipc permissions 2178 * @qbytes: msgq bytes 2179 * @uid: msgq user id 2180 * @gid: msgq group id 2181 * @mode: msgq mode (permissions) 2182 * 2183 * Called only after audit_ipc_obj(). 2184 */ 2185 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode) 2186 { 2187 struct audit_context *context = current->audit_context; 2188 2189 context->ipc.qbytes = qbytes; 2190 context->ipc.perm_uid = uid; 2191 context->ipc.perm_gid = gid; 2192 context->ipc.perm_mode = mode; 2193 context->ipc.has_perm = 1; 2194 } 2195 2196 void __audit_bprm(struct linux_binprm *bprm) 2197 { 2198 struct audit_context *context = current->audit_context; 2199 2200 context->type = AUDIT_EXECVE; 2201 context->execve.argc = bprm->argc; 2202 } 2203 2204 2205 /** 2206 * __audit_socketcall - record audit data for sys_socketcall 2207 * @nargs: number of args, which should not be more than AUDITSC_ARGS. 2208 * @args: args array 2209 * 2210 */ 2211 int __audit_socketcall(int nargs, unsigned long *args) 2212 { 2213 struct audit_context *context = current->audit_context; 2214 2215 if (nargs <= 0 || nargs > AUDITSC_ARGS || !args) 2216 return -EINVAL; 2217 context->type = AUDIT_SOCKETCALL; 2218 context->socketcall.nargs = nargs; 2219 memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long)); 2220 return 0; 2221 } 2222 2223 /** 2224 * __audit_fd_pair - record audit data for pipe and socketpair 2225 * @fd1: the first file descriptor 2226 * @fd2: the second file descriptor 2227 * 2228 */ 2229 void __audit_fd_pair(int fd1, int fd2) 2230 { 2231 struct audit_context *context = current->audit_context; 2232 context->fds[0] = fd1; 2233 context->fds[1] = fd2; 2234 } 2235 2236 /** 2237 * __audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto 2238 * @len: data length in user space 2239 * @a: data address in kernel space 2240 * 2241 * Returns 0 for success or NULL context or < 0 on error. 2242 */ 2243 int __audit_sockaddr(int len, void *a) 2244 { 2245 struct audit_context *context = current->audit_context; 2246 2247 if (!context->sockaddr) { 2248 void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL); 2249 if (!p) 2250 return -ENOMEM; 2251 context->sockaddr = p; 2252 } 2253 2254 context->sockaddr_len = len; 2255 memcpy(context->sockaddr, a, len); 2256 return 0; 2257 } 2258 2259 void __audit_ptrace(struct task_struct *t) 2260 { 2261 struct audit_context *context = current->audit_context; 2262 2263 context->target_pid = task_tgid_nr(t); 2264 context->target_auid = audit_get_loginuid(t); 2265 context->target_uid = task_uid(t); 2266 context->target_sessionid = audit_get_sessionid(t); 2267 security_task_getsecid(t, &context->target_sid); 2268 memcpy(context->target_comm, t->comm, TASK_COMM_LEN); 2269 } 2270 2271 /** 2272 * audit_signal_info - record signal info for shutting down audit subsystem 2273 * @sig: signal value 2274 * @t: task being signaled 2275 * 2276 * If the audit subsystem is being terminated, record the task (pid) 2277 * and uid that is doing that. 2278 */ 2279 int audit_signal_info(int sig, struct task_struct *t) 2280 { 2281 struct audit_aux_data_pids *axp; 2282 struct task_struct *tsk = current; 2283 struct audit_context *ctx = tsk->audit_context; 2284 kuid_t uid = current_uid(), t_uid = task_uid(t); 2285 2286 if (auditd_test_task(t) && 2287 (sig == SIGTERM || sig == SIGHUP || 2288 sig == SIGUSR1 || sig == SIGUSR2)) { 2289 audit_sig_pid = task_tgid_nr(tsk); 2290 if (uid_valid(tsk->loginuid)) 2291 audit_sig_uid = tsk->loginuid; 2292 else 2293 audit_sig_uid = uid; 2294 security_task_getsecid(tsk, &audit_sig_sid); 2295 } 2296 2297 if (!audit_signals || audit_dummy_context()) 2298 return 0; 2299 2300 /* optimize the common case by putting first signal recipient directly 2301 * in audit_context */ 2302 if (!ctx->target_pid) { 2303 ctx->target_pid = task_tgid_nr(t); 2304 ctx->target_auid = audit_get_loginuid(t); 2305 ctx->target_uid = t_uid; 2306 ctx->target_sessionid = audit_get_sessionid(t); 2307 security_task_getsecid(t, &ctx->target_sid); 2308 memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); 2309 return 0; 2310 } 2311 2312 axp = (void *)ctx->aux_pids; 2313 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { 2314 axp = kzalloc(sizeof(*axp), GFP_ATOMIC); 2315 if (!axp) 2316 return -ENOMEM; 2317 2318 axp->d.type = AUDIT_OBJ_PID; 2319 axp->d.next = ctx->aux_pids; 2320 ctx->aux_pids = (void *)axp; 2321 } 2322 BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); 2323 2324 axp->target_pid[axp->pid_count] = task_tgid_nr(t); 2325 axp->target_auid[axp->pid_count] = audit_get_loginuid(t); 2326 axp->target_uid[axp->pid_count] = t_uid; 2327 axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); 2328 security_task_getsecid(t, &axp->target_sid[axp->pid_count]); 2329 memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); 2330 axp->pid_count++; 2331 2332 return 0; 2333 } 2334 2335 /** 2336 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps 2337 * @bprm: pointer to the bprm being processed 2338 * @new: the proposed new credentials 2339 * @old: the old credentials 2340 * 2341 * Simply check if the proc already has the caps given by the file and if not 2342 * store the priv escalation info for later auditing at the end of the syscall 2343 * 2344 * -Eric 2345 */ 2346 int __audit_log_bprm_fcaps(struct linux_binprm *bprm, 2347 const struct cred *new, const struct cred *old) 2348 { 2349 struct audit_aux_data_bprm_fcaps *ax; 2350 struct audit_context *context = current->audit_context; 2351 struct cpu_vfs_cap_data vcaps; 2352 2353 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 2354 if (!ax) 2355 return -ENOMEM; 2356 2357 ax->d.type = AUDIT_BPRM_FCAPS; 2358 ax->d.next = context->aux; 2359 context->aux = (void *)ax; 2360 2361 get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps); 2362 2363 ax->fcap.permitted = vcaps.permitted; 2364 ax->fcap.inheritable = vcaps.inheritable; 2365 ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); 2366 ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; 2367 2368 ax->old_pcap.permitted = old->cap_permitted; 2369 ax->old_pcap.inheritable = old->cap_inheritable; 2370 ax->old_pcap.effective = old->cap_effective; 2371 ax->old_pcap.ambient = old->cap_ambient; 2372 2373 ax->new_pcap.permitted = new->cap_permitted; 2374 ax->new_pcap.inheritable = new->cap_inheritable; 2375 ax->new_pcap.effective = new->cap_effective; 2376 ax->new_pcap.ambient = new->cap_ambient; 2377 return 0; 2378 } 2379 2380 /** 2381 * __audit_log_capset - store information about the arguments to the capset syscall 2382 * @new: the new credentials 2383 * @old: the old (current) credentials 2384 * 2385 * Record the arguments userspace sent to sys_capset for later printing by the 2386 * audit system if applicable 2387 */ 2388 void __audit_log_capset(const struct cred *new, const struct cred *old) 2389 { 2390 struct audit_context *context = current->audit_context; 2391 context->capset.pid = task_tgid_nr(current); 2392 context->capset.cap.effective = new->cap_effective; 2393 context->capset.cap.inheritable = new->cap_effective; 2394 context->capset.cap.permitted = new->cap_permitted; 2395 context->capset.cap.ambient = new->cap_ambient; 2396 context->type = AUDIT_CAPSET; 2397 } 2398 2399 void __audit_mmap_fd(int fd, int flags) 2400 { 2401 struct audit_context *context = current->audit_context; 2402 context->mmap.fd = fd; 2403 context->mmap.flags = flags; 2404 context->type = AUDIT_MMAP; 2405 } 2406 2407 void __audit_log_kern_module(char *name) 2408 { 2409 struct audit_context *context = current->audit_context; 2410 2411 context->module.name = kmalloc(strlen(name) + 1, GFP_KERNEL); 2412 strcpy(context->module.name, name); 2413 context->type = AUDIT_KERN_MODULE; 2414 } 2415 2416 void __audit_fanotify(unsigned int response) 2417 { 2418 audit_log(current->audit_context, GFP_KERNEL, 2419 AUDIT_FANOTIFY, "resp=%u", response); 2420 } 2421 2422 static void audit_log_task(struct audit_buffer *ab) 2423 { 2424 kuid_t auid, uid; 2425 kgid_t gid; 2426 unsigned int sessionid; 2427 char comm[sizeof(current->comm)]; 2428 2429 auid = audit_get_loginuid(current); 2430 sessionid = audit_get_sessionid(current); 2431 current_uid_gid(&uid, &gid); 2432 2433 audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", 2434 from_kuid(&init_user_ns, auid), 2435 from_kuid(&init_user_ns, uid), 2436 from_kgid(&init_user_ns, gid), 2437 sessionid); 2438 audit_log_task_context(ab); 2439 audit_log_format(ab, " pid=%d comm=", task_tgid_nr(current)); 2440 audit_log_untrustedstring(ab, get_task_comm(comm, current)); 2441 audit_log_d_path_exe(ab, current->mm); 2442 } 2443 2444 /** 2445 * audit_core_dumps - record information about processes that end abnormally 2446 * @signr: signal value 2447 * 2448 * If a process ends with a core dump, something fishy is going on and we 2449 * should record the event for investigation. 2450 */ 2451 void audit_core_dumps(long signr) 2452 { 2453 struct audit_buffer *ab; 2454 2455 if (!audit_enabled) 2456 return; 2457 2458 if (signr == SIGQUIT) /* don't care for those */ 2459 return; 2460 2461 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); 2462 if (unlikely(!ab)) 2463 return; 2464 audit_log_task(ab); 2465 audit_log_format(ab, " sig=%ld res=1", signr); 2466 audit_log_end(ab); 2467 } 2468 2469 void __audit_seccomp(unsigned long syscall, long signr, int code) 2470 { 2471 struct audit_buffer *ab; 2472 2473 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_SECCOMP); 2474 if (unlikely(!ab)) 2475 return; 2476 audit_log_task(ab); 2477 audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x", 2478 signr, syscall_get_arch(), syscall, 2479 in_compat_syscall(), KSTK_EIP(current), code); 2480 audit_log_end(ab); 2481 } 2482 2483 struct list_head *audit_killed_trees(void) 2484 { 2485 struct audit_context *ctx = current->audit_context; 2486 if (likely(!ctx || !ctx->in_syscall)) 2487 return NULL; 2488 return &ctx->killed_trees; 2489 } 2490