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