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