Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame] | 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/tty.h> |
| 67 | #include <linux/binfmts.h> |
| 68 | #include <linux/highmem.h> |
| 69 | #include <linux/syscalls.h> |
| 70 | #include <asm/syscall.h> |
| 71 | #include <linux/capability.h> |
| 72 | #include <linux/fs_struct.h> |
| 73 | #include <linux/compat.h> |
| 74 | #include <linux/ctype.h> |
| 75 | #include <linux/string.h> |
| 76 | #include <linux/uaccess.h> |
| 77 | #include <uapi/linux/limits.h> |
| 78 | |
| 79 | #include "audit.h" |
| 80 | |
| 81 | /* flags stating the success for a syscall */ |
| 82 | #define AUDITSC_INVALID 0 |
| 83 | #define AUDITSC_SUCCESS 1 |
| 84 | #define AUDITSC_FAILURE 2 |
| 85 | |
| 86 | /* no execve audit message should be longer than this (userspace limits), |
| 87 | * see the note near the top of audit_log_execve_info() about this value */ |
| 88 | #define MAX_EXECVE_AUDIT_LEN 7500 |
| 89 | |
| 90 | /* max length to print of cmdline/proctitle value during audit */ |
| 91 | #define MAX_PROCTITLE_AUDIT_LEN 128 |
| 92 | |
| 93 | /* number of audit rules */ |
| 94 | int audit_n_rules; |
| 95 | |
| 96 | /* determines whether we collect data for signals sent */ |
| 97 | int audit_signals; |
| 98 | |
| 99 | struct audit_aux_data { |
| 100 | struct audit_aux_data *next; |
| 101 | int type; |
| 102 | }; |
| 103 | |
| 104 | #define AUDIT_AUX_IPCPERM 0 |
| 105 | |
| 106 | /* Number of target pids per aux struct. */ |
| 107 | #define AUDIT_AUX_PIDS 16 |
| 108 | |
| 109 | struct audit_aux_data_pids { |
| 110 | struct audit_aux_data d; |
| 111 | pid_t target_pid[AUDIT_AUX_PIDS]; |
| 112 | kuid_t target_auid[AUDIT_AUX_PIDS]; |
| 113 | kuid_t target_uid[AUDIT_AUX_PIDS]; |
| 114 | unsigned int target_sessionid[AUDIT_AUX_PIDS]; |
| 115 | u32 target_sid[AUDIT_AUX_PIDS]; |
| 116 | char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN]; |
| 117 | int pid_count; |
| 118 | }; |
| 119 | |
| 120 | struct audit_aux_data_bprm_fcaps { |
| 121 | struct audit_aux_data d; |
| 122 | struct audit_cap_data fcap; |
| 123 | unsigned int fcap_ver; |
| 124 | struct audit_cap_data old_pcap; |
| 125 | struct audit_cap_data new_pcap; |
| 126 | }; |
| 127 | |
| 128 | struct audit_tree_refs { |
| 129 | struct audit_tree_refs *next; |
| 130 | struct audit_chunk *c[31]; |
| 131 | }; |
| 132 | |
| 133 | static int audit_match_perm(struct audit_context *ctx, int mask) |
| 134 | { |
| 135 | unsigned n; |
| 136 | if (unlikely(!ctx)) |
| 137 | return 0; |
| 138 | n = ctx->major; |
| 139 | |
| 140 | switch (audit_classify_syscall(ctx->arch, n)) { |
| 141 | case 0: /* native */ |
| 142 | if ((mask & AUDIT_PERM_WRITE) && |
| 143 | audit_match_class(AUDIT_CLASS_WRITE, n)) |
| 144 | return 1; |
| 145 | if ((mask & AUDIT_PERM_READ) && |
| 146 | audit_match_class(AUDIT_CLASS_READ, n)) |
| 147 | return 1; |
| 148 | if ((mask & AUDIT_PERM_ATTR) && |
| 149 | audit_match_class(AUDIT_CLASS_CHATTR, n)) |
| 150 | return 1; |
| 151 | return 0; |
| 152 | case 1: /* 32bit on biarch */ |
| 153 | if ((mask & AUDIT_PERM_WRITE) && |
| 154 | audit_match_class(AUDIT_CLASS_WRITE_32, n)) |
| 155 | return 1; |
| 156 | if ((mask & AUDIT_PERM_READ) && |
| 157 | audit_match_class(AUDIT_CLASS_READ_32, n)) |
| 158 | return 1; |
| 159 | if ((mask & AUDIT_PERM_ATTR) && |
| 160 | audit_match_class(AUDIT_CLASS_CHATTR_32, n)) |
| 161 | return 1; |
| 162 | return 0; |
| 163 | case 2: /* open */ |
| 164 | return mask & ACC_MODE(ctx->argv[1]); |
| 165 | case 3: /* openat */ |
| 166 | return mask & ACC_MODE(ctx->argv[2]); |
| 167 | case 4: /* socketcall */ |
| 168 | return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); |
| 169 | case 5: /* execve */ |
| 170 | return mask & AUDIT_PERM_EXEC; |
| 171 | default: |
| 172 | return 0; |
| 173 | } |
| 174 | } |
| 175 | |
| 176 | static int audit_match_filetype(struct audit_context *ctx, int val) |
| 177 | { |
| 178 | struct audit_names *n; |
| 179 | umode_t mode = (umode_t)val; |
| 180 | |
| 181 | if (unlikely(!ctx)) |
| 182 | return 0; |
| 183 | |
| 184 | list_for_each_entry(n, &ctx->names_list, list) { |
| 185 | if ((n->ino != AUDIT_INO_UNSET) && |
| 186 | ((n->mode & S_IFMT) == mode)) |
| 187 | return 1; |
| 188 | } |
| 189 | |
| 190 | return 0; |
| 191 | } |
| 192 | |
| 193 | /* |
| 194 | * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *; |
| 195 | * ->first_trees points to its beginning, ->trees - to the current end of data. |
| 196 | * ->tree_count is the number of free entries in array pointed to by ->trees. |
| 197 | * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL, |
| 198 | * "empty" becomes (p, p, 31) afterwards. We don't shrink the list (and seriously, |
| 199 | * it's going to remain 1-element for almost any setup) until we free context itself. |
| 200 | * References in it _are_ dropped - at the same time we free/drop aux stuff. |
| 201 | */ |
| 202 | |
| 203 | #ifdef CONFIG_AUDIT_TREE |
| 204 | static void audit_set_auditable(struct audit_context *ctx) |
| 205 | { |
| 206 | if (!ctx->prio) { |
| 207 | ctx->prio = 1; |
| 208 | ctx->current_state = AUDIT_RECORD_CONTEXT; |
| 209 | } |
| 210 | } |
| 211 | |
| 212 | static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk) |
| 213 | { |
| 214 | struct audit_tree_refs *p = ctx->trees; |
| 215 | int left = ctx->tree_count; |
| 216 | if (likely(left)) { |
| 217 | p->c[--left] = chunk; |
| 218 | ctx->tree_count = left; |
| 219 | return 1; |
| 220 | } |
| 221 | if (!p) |
| 222 | return 0; |
| 223 | p = p->next; |
| 224 | if (p) { |
| 225 | p->c[30] = chunk; |
| 226 | ctx->trees = p; |
| 227 | ctx->tree_count = 30; |
| 228 | return 1; |
| 229 | } |
| 230 | return 0; |
| 231 | } |
| 232 | |
| 233 | static int grow_tree_refs(struct audit_context *ctx) |
| 234 | { |
| 235 | struct audit_tree_refs *p = ctx->trees; |
| 236 | ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL); |
| 237 | if (!ctx->trees) { |
| 238 | ctx->trees = p; |
| 239 | return 0; |
| 240 | } |
| 241 | if (p) |
| 242 | p->next = ctx->trees; |
| 243 | else |
| 244 | ctx->first_trees = ctx->trees; |
| 245 | ctx->tree_count = 31; |
| 246 | return 1; |
| 247 | } |
| 248 | #endif |
| 249 | |
| 250 | static void unroll_tree_refs(struct audit_context *ctx, |
| 251 | struct audit_tree_refs *p, int count) |
| 252 | { |
| 253 | #ifdef CONFIG_AUDIT_TREE |
| 254 | struct audit_tree_refs *q; |
| 255 | int n; |
| 256 | if (!p) { |
| 257 | /* we started with empty chain */ |
| 258 | p = ctx->first_trees; |
| 259 | count = 31; |
| 260 | /* if the very first allocation has failed, nothing to do */ |
| 261 | if (!p) |
| 262 | return; |
| 263 | } |
| 264 | n = count; |
| 265 | for (q = p; q != ctx->trees; q = q->next, n = 31) { |
| 266 | while (n--) { |
| 267 | audit_put_chunk(q->c[n]); |
| 268 | q->c[n] = NULL; |
| 269 | } |
| 270 | } |
| 271 | while (n-- > ctx->tree_count) { |
| 272 | audit_put_chunk(q->c[n]); |
| 273 | q->c[n] = NULL; |
| 274 | } |
| 275 | ctx->trees = p; |
| 276 | ctx->tree_count = count; |
| 277 | #endif |
| 278 | } |
| 279 | |
| 280 | static void free_tree_refs(struct audit_context *ctx) |
| 281 | { |
| 282 | struct audit_tree_refs *p, *q; |
| 283 | for (p = ctx->first_trees; p; p = q) { |
| 284 | q = p->next; |
| 285 | kfree(p); |
| 286 | } |
| 287 | } |
| 288 | |
| 289 | static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree) |
| 290 | { |
| 291 | #ifdef CONFIG_AUDIT_TREE |
| 292 | struct audit_tree_refs *p; |
| 293 | int n; |
| 294 | if (!tree) |
| 295 | return 0; |
| 296 | /* full ones */ |
| 297 | for (p = ctx->first_trees; p != ctx->trees; p = p->next) { |
| 298 | for (n = 0; n < 31; n++) |
| 299 | if (audit_tree_match(p->c[n], tree)) |
| 300 | return 1; |
| 301 | } |
| 302 | /* partial */ |
| 303 | if (p) { |
| 304 | for (n = ctx->tree_count; n < 31; n++) |
| 305 | if (audit_tree_match(p->c[n], tree)) |
| 306 | return 1; |
| 307 | } |
| 308 | #endif |
| 309 | return 0; |
| 310 | } |
| 311 | |
| 312 | static int audit_compare_uid(kuid_t uid, |
| 313 | struct audit_names *name, |
| 314 | struct audit_field *f, |
| 315 | struct audit_context *ctx) |
| 316 | { |
| 317 | struct audit_names *n; |
| 318 | int rc; |
| 319 | |
| 320 | if (name) { |
| 321 | rc = audit_uid_comparator(uid, f->op, name->uid); |
| 322 | if (rc) |
| 323 | return rc; |
| 324 | } |
| 325 | |
| 326 | if (ctx) { |
| 327 | list_for_each_entry(n, &ctx->names_list, list) { |
| 328 | rc = audit_uid_comparator(uid, f->op, n->uid); |
| 329 | if (rc) |
| 330 | return rc; |
| 331 | } |
| 332 | } |
| 333 | return 0; |
| 334 | } |
| 335 | |
| 336 | static int audit_compare_gid(kgid_t gid, |
| 337 | struct audit_names *name, |
| 338 | struct audit_field *f, |
| 339 | struct audit_context *ctx) |
| 340 | { |
| 341 | struct audit_names *n; |
| 342 | int rc; |
| 343 | |
| 344 | if (name) { |
| 345 | rc = audit_gid_comparator(gid, f->op, name->gid); |
| 346 | if (rc) |
| 347 | return rc; |
| 348 | } |
| 349 | |
| 350 | if (ctx) { |
| 351 | list_for_each_entry(n, &ctx->names_list, list) { |
| 352 | rc = audit_gid_comparator(gid, f->op, n->gid); |
| 353 | if (rc) |
| 354 | return rc; |
| 355 | } |
| 356 | } |
| 357 | return 0; |
| 358 | } |
| 359 | |
| 360 | static int audit_field_compare(struct task_struct *tsk, |
| 361 | const struct cred *cred, |
| 362 | struct audit_field *f, |
| 363 | struct audit_context *ctx, |
| 364 | struct audit_names *name) |
| 365 | { |
| 366 | switch (f->val) { |
| 367 | /* process to file object comparisons */ |
| 368 | case AUDIT_COMPARE_UID_TO_OBJ_UID: |
| 369 | return audit_compare_uid(cred->uid, name, f, ctx); |
| 370 | case AUDIT_COMPARE_GID_TO_OBJ_GID: |
| 371 | return audit_compare_gid(cred->gid, name, f, ctx); |
| 372 | case AUDIT_COMPARE_EUID_TO_OBJ_UID: |
| 373 | return audit_compare_uid(cred->euid, name, f, ctx); |
| 374 | case AUDIT_COMPARE_EGID_TO_OBJ_GID: |
| 375 | return audit_compare_gid(cred->egid, name, f, ctx); |
| 376 | case AUDIT_COMPARE_AUID_TO_OBJ_UID: |
| 377 | return audit_compare_uid(tsk->loginuid, name, f, ctx); |
| 378 | case AUDIT_COMPARE_SUID_TO_OBJ_UID: |
| 379 | return audit_compare_uid(cred->suid, name, f, ctx); |
| 380 | case AUDIT_COMPARE_SGID_TO_OBJ_GID: |
| 381 | return audit_compare_gid(cred->sgid, name, f, ctx); |
| 382 | case AUDIT_COMPARE_FSUID_TO_OBJ_UID: |
| 383 | return audit_compare_uid(cred->fsuid, name, f, ctx); |
| 384 | case AUDIT_COMPARE_FSGID_TO_OBJ_GID: |
| 385 | return audit_compare_gid(cred->fsgid, name, f, ctx); |
| 386 | /* uid comparisons */ |
| 387 | case AUDIT_COMPARE_UID_TO_AUID: |
| 388 | return audit_uid_comparator(cred->uid, f->op, tsk->loginuid); |
| 389 | case AUDIT_COMPARE_UID_TO_EUID: |
| 390 | return audit_uid_comparator(cred->uid, f->op, cred->euid); |
| 391 | case AUDIT_COMPARE_UID_TO_SUID: |
| 392 | return audit_uid_comparator(cred->uid, f->op, cred->suid); |
| 393 | case AUDIT_COMPARE_UID_TO_FSUID: |
| 394 | return audit_uid_comparator(cred->uid, f->op, cred->fsuid); |
| 395 | /* auid comparisons */ |
| 396 | case AUDIT_COMPARE_AUID_TO_EUID: |
| 397 | return audit_uid_comparator(tsk->loginuid, f->op, cred->euid); |
| 398 | case AUDIT_COMPARE_AUID_TO_SUID: |
| 399 | return audit_uid_comparator(tsk->loginuid, f->op, cred->suid); |
| 400 | case AUDIT_COMPARE_AUID_TO_FSUID: |
| 401 | return audit_uid_comparator(tsk->loginuid, f->op, cred->fsuid); |
| 402 | /* euid comparisons */ |
| 403 | case AUDIT_COMPARE_EUID_TO_SUID: |
| 404 | return audit_uid_comparator(cred->euid, f->op, cred->suid); |
| 405 | case AUDIT_COMPARE_EUID_TO_FSUID: |
| 406 | return audit_uid_comparator(cred->euid, f->op, cred->fsuid); |
| 407 | /* suid comparisons */ |
| 408 | case AUDIT_COMPARE_SUID_TO_FSUID: |
| 409 | return audit_uid_comparator(cred->suid, f->op, cred->fsuid); |
| 410 | /* gid comparisons */ |
| 411 | case AUDIT_COMPARE_GID_TO_EGID: |
| 412 | return audit_gid_comparator(cred->gid, f->op, cred->egid); |
| 413 | case AUDIT_COMPARE_GID_TO_SGID: |
| 414 | return audit_gid_comparator(cred->gid, f->op, cred->sgid); |
| 415 | case AUDIT_COMPARE_GID_TO_FSGID: |
| 416 | return audit_gid_comparator(cred->gid, f->op, cred->fsgid); |
| 417 | /* egid comparisons */ |
| 418 | case AUDIT_COMPARE_EGID_TO_SGID: |
| 419 | return audit_gid_comparator(cred->egid, f->op, cred->sgid); |
| 420 | case AUDIT_COMPARE_EGID_TO_FSGID: |
| 421 | return audit_gid_comparator(cred->egid, f->op, cred->fsgid); |
| 422 | /* sgid comparison */ |
| 423 | case AUDIT_COMPARE_SGID_TO_FSGID: |
| 424 | return audit_gid_comparator(cred->sgid, f->op, cred->fsgid); |
| 425 | default: |
| 426 | WARN(1, "Missing AUDIT_COMPARE define. Report as a bug\n"); |
| 427 | return 0; |
| 428 | } |
| 429 | return 0; |
| 430 | } |
| 431 | |
| 432 | /* Determine if any context name data matches a rule's watch data */ |
| 433 | /* Compare a task_struct with an audit_rule. Return 1 on match, 0 |
| 434 | * otherwise. |
| 435 | * |
| 436 | * If task_creation is true, this is an explicit indication that we are |
| 437 | * filtering a task rule at task creation time. This and tsk == current are |
| 438 | * the only situations where tsk->cred may be accessed without an rcu read lock. |
| 439 | */ |
| 440 | static int audit_filter_rules(struct task_struct *tsk, |
| 441 | struct audit_krule *rule, |
| 442 | struct audit_context *ctx, |
| 443 | struct audit_names *name, |
| 444 | enum audit_state *state, |
| 445 | bool task_creation) |
| 446 | { |
| 447 | const struct cred *cred; |
| 448 | int i, need_sid = 1; |
| 449 | u32 sid; |
| 450 | |
| 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_pid_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_PERS: |
| 513 | result = audit_comparator(tsk->personality, f->op, f->val); |
| 514 | break; |
| 515 | case AUDIT_ARCH: |
| 516 | if (ctx) |
| 517 | result = audit_comparator(ctx->arch, f->op, f->val); |
| 518 | break; |
| 519 | |
| 520 | case AUDIT_EXIT: |
| 521 | if (ctx && ctx->return_valid) |
| 522 | result = audit_comparator(ctx->return_code, f->op, f->val); |
| 523 | break; |
| 524 | case AUDIT_SUCCESS: |
| 525 | if (ctx && ctx->return_valid) { |
| 526 | if (f->val) |
| 527 | result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS); |
| 528 | else |
| 529 | result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE); |
| 530 | } |
| 531 | break; |
| 532 | case AUDIT_DEVMAJOR: |
| 533 | if (name) { |
| 534 | if (audit_comparator(MAJOR(name->dev), f->op, f->val) || |
| 535 | audit_comparator(MAJOR(name->rdev), f->op, f->val)) |
| 536 | ++result; |
| 537 | } else if (ctx) { |
| 538 | list_for_each_entry(n, &ctx->names_list, list) { |
| 539 | if (audit_comparator(MAJOR(n->dev), f->op, f->val) || |
| 540 | audit_comparator(MAJOR(n->rdev), f->op, f->val)) { |
| 541 | ++result; |
| 542 | break; |
| 543 | } |
| 544 | } |
| 545 | } |
| 546 | break; |
| 547 | case AUDIT_DEVMINOR: |
| 548 | if (name) { |
| 549 | if (audit_comparator(MINOR(name->dev), f->op, f->val) || |
| 550 | audit_comparator(MINOR(name->rdev), f->op, f->val)) |
| 551 | ++result; |
| 552 | } else if (ctx) { |
| 553 | list_for_each_entry(n, &ctx->names_list, list) { |
| 554 | if (audit_comparator(MINOR(n->dev), f->op, f->val) || |
| 555 | audit_comparator(MINOR(n->rdev), f->op, f->val)) { |
| 556 | ++result; |
| 557 | break; |
| 558 | } |
| 559 | } |
| 560 | } |
| 561 | break; |
| 562 | case AUDIT_INODE: |
| 563 | if (name) |
| 564 | result = audit_comparator(name->ino, f->op, f->val); |
| 565 | else if (ctx) { |
| 566 | list_for_each_entry(n, &ctx->names_list, list) { |
| 567 | if (audit_comparator(n->ino, f->op, f->val)) { |
| 568 | ++result; |
| 569 | break; |
| 570 | } |
| 571 | } |
| 572 | } |
| 573 | break; |
| 574 | case AUDIT_OBJ_UID: |
| 575 | if (name) { |
| 576 | result = audit_uid_comparator(name->uid, f->op, f->uid); |
| 577 | } else if (ctx) { |
| 578 | list_for_each_entry(n, &ctx->names_list, list) { |
| 579 | if (audit_uid_comparator(n->uid, f->op, f->uid)) { |
| 580 | ++result; |
| 581 | break; |
| 582 | } |
| 583 | } |
| 584 | } |
| 585 | break; |
| 586 | case AUDIT_OBJ_GID: |
| 587 | if (name) { |
| 588 | result = audit_gid_comparator(name->gid, f->op, f->gid); |
| 589 | } else if (ctx) { |
| 590 | list_for_each_entry(n, &ctx->names_list, list) { |
| 591 | if (audit_gid_comparator(n->gid, f->op, f->gid)) { |
| 592 | ++result; |
| 593 | break; |
| 594 | } |
| 595 | } |
| 596 | } |
| 597 | break; |
| 598 | case AUDIT_WATCH: |
| 599 | if (name) |
| 600 | result = audit_watch_compare(rule->watch, name->ino, name->dev); |
| 601 | break; |
| 602 | case AUDIT_DIR: |
| 603 | if (ctx) |
| 604 | result = match_tree_refs(ctx, rule->tree); |
| 605 | break; |
| 606 | case AUDIT_LOGINUID: |
| 607 | result = audit_uid_comparator(tsk->loginuid, f->op, f->uid); |
| 608 | break; |
| 609 | case AUDIT_LOGINUID_SET: |
| 610 | result = audit_comparator(audit_loginuid_set(tsk), f->op, f->val); |
| 611 | break; |
| 612 | case AUDIT_SUBJ_USER: |
| 613 | case AUDIT_SUBJ_ROLE: |
| 614 | case AUDIT_SUBJ_TYPE: |
| 615 | case AUDIT_SUBJ_SEN: |
| 616 | case AUDIT_SUBJ_CLR: |
| 617 | /* NOTE: this may return negative values indicating |
| 618 | a temporary error. We simply treat this as a |
| 619 | match for now to avoid losing information that |
| 620 | may be wanted. An error message will also be |
| 621 | logged upon error */ |
| 622 | if (f->lsm_rule) { |
| 623 | if (need_sid) { |
| 624 | security_task_getsecid(tsk, &sid); |
| 625 | need_sid = 0; |
| 626 | } |
| 627 | result = security_audit_rule_match(sid, f->type, |
| 628 | f->op, |
| 629 | f->lsm_rule, |
| 630 | ctx); |
| 631 | } |
| 632 | break; |
| 633 | case AUDIT_OBJ_USER: |
| 634 | case AUDIT_OBJ_ROLE: |
| 635 | case AUDIT_OBJ_TYPE: |
| 636 | case AUDIT_OBJ_LEV_LOW: |
| 637 | case AUDIT_OBJ_LEV_HIGH: |
| 638 | /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR |
| 639 | also applies here */ |
| 640 | if (f->lsm_rule) { |
| 641 | /* Find files that match */ |
| 642 | if (name) { |
| 643 | result = security_audit_rule_match( |
| 644 | name->osid, f->type, f->op, |
| 645 | f->lsm_rule, ctx); |
| 646 | } else if (ctx) { |
| 647 | list_for_each_entry(n, &ctx->names_list, list) { |
| 648 | if (security_audit_rule_match(n->osid, f->type, |
| 649 | f->op, f->lsm_rule, |
| 650 | ctx)) { |
| 651 | ++result; |
| 652 | break; |
| 653 | } |
| 654 | } |
| 655 | } |
| 656 | /* Find ipc objects that match */ |
| 657 | if (!ctx || ctx->type != AUDIT_IPC) |
| 658 | break; |
| 659 | if (security_audit_rule_match(ctx->ipc.osid, |
| 660 | f->type, f->op, |
| 661 | f->lsm_rule, ctx)) |
| 662 | ++result; |
| 663 | } |
| 664 | break; |
| 665 | case AUDIT_ARG0: |
| 666 | case AUDIT_ARG1: |
| 667 | case AUDIT_ARG2: |
| 668 | case AUDIT_ARG3: |
| 669 | if (ctx) |
| 670 | result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val); |
| 671 | break; |
| 672 | case AUDIT_FILTERKEY: |
| 673 | /* ignore this field for filtering */ |
| 674 | result = 1; |
| 675 | break; |
| 676 | case AUDIT_PERM: |
| 677 | result = audit_match_perm(ctx, f->val); |
| 678 | break; |
| 679 | case AUDIT_FILETYPE: |
| 680 | result = audit_match_filetype(ctx, f->val); |
| 681 | break; |
| 682 | case AUDIT_FIELD_COMPARE: |
| 683 | result = audit_field_compare(tsk, cred, f, ctx, name); |
| 684 | break; |
| 685 | } |
| 686 | if (!result) |
| 687 | return 0; |
| 688 | } |
| 689 | |
| 690 | if (ctx) { |
| 691 | if (rule->prio <= ctx->prio) |
| 692 | return 0; |
| 693 | if (rule->filterkey) { |
| 694 | kfree(ctx->filterkey); |
| 695 | ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC); |
| 696 | } |
| 697 | ctx->prio = rule->prio; |
| 698 | } |
| 699 | switch (rule->action) { |
| 700 | case AUDIT_NEVER: *state = AUDIT_DISABLED; break; |
| 701 | case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; |
| 702 | } |
| 703 | return 1; |
| 704 | } |
| 705 | |
| 706 | /* At process creation time, we can determine if system-call auditing is |
| 707 | * completely disabled for this task. Since we only have the task |
| 708 | * structure at this point, we can only check uid and gid. |
| 709 | */ |
| 710 | static enum audit_state audit_filter_task(struct task_struct *tsk, char **key) |
| 711 | { |
| 712 | struct audit_entry *e; |
| 713 | enum audit_state state; |
| 714 | |
| 715 | rcu_read_lock(); |
| 716 | list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { |
| 717 | if (audit_filter_rules(tsk, &e->rule, NULL, NULL, |
| 718 | &state, true)) { |
| 719 | if (state == AUDIT_RECORD_CONTEXT) |
| 720 | *key = kstrdup(e->rule.filterkey, GFP_ATOMIC); |
| 721 | rcu_read_unlock(); |
| 722 | return state; |
| 723 | } |
| 724 | } |
| 725 | rcu_read_unlock(); |
| 726 | return AUDIT_BUILD_CONTEXT; |
| 727 | } |
| 728 | |
| 729 | static int audit_in_mask(const struct audit_krule *rule, unsigned long val) |
| 730 | { |
| 731 | int word, bit; |
| 732 | |
| 733 | if (val > 0xffffffff) |
| 734 | return false; |
| 735 | |
| 736 | word = AUDIT_WORD(val); |
| 737 | if (word >= AUDIT_BITMASK_SIZE) |
| 738 | return false; |
| 739 | |
| 740 | bit = AUDIT_BIT(val); |
| 741 | |
| 742 | return rule->mask[word] & bit; |
| 743 | } |
| 744 | |
| 745 | /* At syscall entry and exit time, this filter is called if the |
| 746 | * audit_state is not low enough that auditing cannot take place, but is |
| 747 | * also not high enough that we already know we have to write an audit |
| 748 | * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). |
| 749 | */ |
| 750 | static enum audit_state audit_filter_syscall(struct task_struct *tsk, |
| 751 | struct audit_context *ctx, |
| 752 | struct list_head *list) |
| 753 | { |
| 754 | struct audit_entry *e; |
| 755 | enum audit_state state; |
| 756 | |
| 757 | if (audit_pid && tsk->tgid == audit_pid) |
| 758 | return AUDIT_DISABLED; |
| 759 | |
| 760 | rcu_read_lock(); |
| 761 | if (!list_empty(list)) { |
| 762 | list_for_each_entry_rcu(e, list, list) { |
| 763 | if (audit_in_mask(&e->rule, ctx->major) && |
| 764 | audit_filter_rules(tsk, &e->rule, ctx, NULL, |
| 765 | &state, false)) { |
| 766 | rcu_read_unlock(); |
| 767 | ctx->current_state = state; |
| 768 | return state; |
| 769 | } |
| 770 | } |
| 771 | } |
| 772 | rcu_read_unlock(); |
| 773 | return AUDIT_BUILD_CONTEXT; |
| 774 | } |
| 775 | |
| 776 | /* |
| 777 | * Given an audit_name check the inode hash table to see if they match. |
| 778 | * Called holding the rcu read lock to protect the use of audit_inode_hash |
| 779 | */ |
| 780 | static int audit_filter_inode_name(struct task_struct *tsk, |
| 781 | struct audit_names *n, |
| 782 | struct audit_context *ctx) { |
| 783 | int h = audit_hash_ino((u32)n->ino); |
| 784 | struct list_head *list = &audit_inode_hash[h]; |
| 785 | struct audit_entry *e; |
| 786 | enum audit_state state; |
| 787 | |
| 788 | if (list_empty(list)) |
| 789 | return 0; |
| 790 | |
| 791 | list_for_each_entry_rcu(e, list, list) { |
| 792 | if (audit_in_mask(&e->rule, ctx->major) && |
| 793 | audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) { |
| 794 | ctx->current_state = state; |
| 795 | return 1; |
| 796 | } |
| 797 | } |
| 798 | |
| 799 | return 0; |
| 800 | } |
| 801 | |
| 802 | /* At syscall exit time, this filter is called if any audit_names have been |
| 803 | * collected during syscall processing. We only check rules in sublists at hash |
| 804 | * buckets applicable to the inode numbers in audit_names. |
| 805 | * Regarding audit_state, same rules apply as for audit_filter_syscall(). |
| 806 | */ |
| 807 | void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx) |
| 808 | { |
| 809 | struct audit_names *n; |
| 810 | |
| 811 | if (audit_pid && tsk->tgid == audit_pid) |
| 812 | return; |
| 813 | |
| 814 | rcu_read_lock(); |
| 815 | |
| 816 | list_for_each_entry(n, &ctx->names_list, list) { |
| 817 | if (audit_filter_inode_name(tsk, n, ctx)) |
| 818 | break; |
| 819 | } |
| 820 | rcu_read_unlock(); |
| 821 | } |
| 822 | |
| 823 | /* Transfer the audit context pointer to the caller, clearing it in the tsk's struct */ |
| 824 | static inline struct audit_context *audit_take_context(struct task_struct *tsk, |
| 825 | int return_valid, |
| 826 | long return_code) |
| 827 | { |
| 828 | struct audit_context *context = tsk->audit_context; |
| 829 | |
| 830 | if (!context) |
| 831 | return NULL; |
| 832 | context->return_valid = return_valid; |
| 833 | |
| 834 | /* |
| 835 | * we need to fix up the return code in the audit logs if the actual |
| 836 | * return codes are later going to be fixed up by the arch specific |
| 837 | * signal handlers |
| 838 | * |
| 839 | * This is actually a test for: |
| 840 | * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) || |
| 841 | * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK) |
| 842 | * |
| 843 | * but is faster than a bunch of || |
| 844 | */ |
| 845 | if (unlikely(return_code <= -ERESTARTSYS) && |
| 846 | (return_code >= -ERESTART_RESTARTBLOCK) && |
| 847 | (return_code != -ENOIOCTLCMD)) |
| 848 | context->return_code = -EINTR; |
| 849 | else |
| 850 | context->return_code = return_code; |
| 851 | |
| 852 | if (context->in_syscall && !context->dummy) { |
| 853 | audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]); |
| 854 | audit_filter_inodes(tsk, context); |
| 855 | } |
| 856 | |
| 857 | tsk->audit_context = NULL; |
| 858 | return context; |
| 859 | } |
| 860 | |
| 861 | static inline void audit_proctitle_free(struct audit_context *context) |
| 862 | { |
| 863 | kfree(context->proctitle.value); |
| 864 | context->proctitle.value = NULL; |
| 865 | context->proctitle.len = 0; |
| 866 | } |
| 867 | |
| 868 | static inline void audit_free_names(struct audit_context *context) |
| 869 | { |
| 870 | struct audit_names *n, *next; |
| 871 | |
| 872 | list_for_each_entry_safe(n, next, &context->names_list, list) { |
| 873 | list_del(&n->list); |
| 874 | if (n->name) |
| 875 | putname(n->name); |
| 876 | if (n->should_free) |
| 877 | kfree(n); |
| 878 | } |
| 879 | context->name_count = 0; |
| 880 | path_put(&context->pwd); |
| 881 | context->pwd.dentry = NULL; |
| 882 | context->pwd.mnt = NULL; |
| 883 | } |
| 884 | |
| 885 | static inline void audit_free_aux(struct audit_context *context) |
| 886 | { |
| 887 | struct audit_aux_data *aux; |
| 888 | |
| 889 | while ((aux = context->aux)) { |
| 890 | context->aux = aux->next; |
| 891 | kfree(aux); |
| 892 | } |
| 893 | while ((aux = context->aux_pids)) { |
| 894 | context->aux_pids = aux->next; |
| 895 | kfree(aux); |
| 896 | } |
| 897 | } |
| 898 | |
| 899 | static inline struct audit_context *audit_alloc_context(enum audit_state state) |
| 900 | { |
| 901 | struct audit_context *context; |
| 902 | |
| 903 | context = kzalloc(sizeof(*context), GFP_KERNEL); |
| 904 | if (!context) |
| 905 | return NULL; |
| 906 | context->state = state; |
| 907 | context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; |
| 908 | INIT_LIST_HEAD(&context->killed_trees); |
| 909 | INIT_LIST_HEAD(&context->names_list); |
| 910 | return context; |
| 911 | } |
| 912 | |
| 913 | /** |
| 914 | * audit_alloc - allocate an audit context block for a task |
| 915 | * @tsk: task |
| 916 | * |
| 917 | * Filter on the task information and allocate a per-task audit context |
| 918 | * if necessary. Doing so turns on system call auditing for the |
| 919 | * specified task. This is called from copy_process, so no lock is |
| 920 | * needed. |
| 921 | */ |
| 922 | int audit_alloc(struct task_struct *tsk) |
| 923 | { |
| 924 | struct audit_context *context; |
| 925 | enum audit_state state; |
| 926 | char *key = NULL; |
| 927 | |
| 928 | if (likely(!audit_ever_enabled)) |
| 929 | return 0; /* Return if not auditing. */ |
| 930 | |
| 931 | state = audit_filter_task(tsk, &key); |
| 932 | if (state == AUDIT_DISABLED) { |
| 933 | clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); |
| 934 | return 0; |
| 935 | } |
| 936 | |
| 937 | if (!(context = audit_alloc_context(state))) { |
| 938 | kfree(key); |
| 939 | audit_log_lost("out of memory in audit_alloc"); |
| 940 | return -ENOMEM; |
| 941 | } |
| 942 | context->filterkey = key; |
| 943 | |
| 944 | tsk->audit_context = context; |
| 945 | set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); |
| 946 | return 0; |
| 947 | } |
| 948 | |
| 949 | static inline void audit_free_context(struct audit_context *context) |
| 950 | { |
| 951 | audit_free_names(context); |
| 952 | unroll_tree_refs(context, NULL, 0); |
| 953 | free_tree_refs(context); |
| 954 | audit_free_aux(context); |
| 955 | kfree(context->filterkey); |
| 956 | kfree(context->sockaddr); |
| 957 | audit_proctitle_free(context); |
| 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 | static void audit_log_execve_info(struct audit_context *context, |
| 994 | struct audit_buffer **ab) |
| 995 | { |
| 996 | long len_max; |
| 997 | long len_rem; |
| 998 | long len_full; |
| 999 | long len_buf; |
| 1000 | long len_abuf; |
| 1001 | long len_tmp; |
| 1002 | bool require_data; |
| 1003 | bool encode; |
| 1004 | unsigned int iter; |
| 1005 | unsigned int arg; |
| 1006 | char *buf_head; |
| 1007 | char *buf; |
| 1008 | const char __user *p = (const char __user *)current->mm->arg_start; |
| 1009 | |
| 1010 | /* NOTE: this buffer needs to be large enough to hold all the non-arg |
| 1011 | * data we put in the audit record for this argument (see the |
| 1012 | * code below) ... at this point in time 96 is plenty */ |
| 1013 | char abuf[96]; |
| 1014 | |
| 1015 | /* NOTE: we set MAX_EXECVE_AUDIT_LEN to a rather arbitrary limit, the |
| 1016 | * current value of 7500 is not as important as the fact that it |
| 1017 | * is less than 8k, a setting of 7500 gives us plenty of wiggle |
| 1018 | * room if we go over a little bit in the logging below */ |
| 1019 | WARN_ON_ONCE(MAX_EXECVE_AUDIT_LEN > 7500); |
| 1020 | len_max = MAX_EXECVE_AUDIT_LEN; |
| 1021 | |
| 1022 | /* scratch buffer to hold the userspace args */ |
| 1023 | buf_head = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL); |
| 1024 | if (!buf_head) { |
| 1025 | audit_panic("out of memory for argv string"); |
| 1026 | return; |
| 1027 | } |
| 1028 | buf = buf_head; |
| 1029 | |
| 1030 | audit_log_format(*ab, "argc=%d", context->execve.argc); |
| 1031 | |
| 1032 | len_rem = len_max; |
| 1033 | len_buf = 0; |
| 1034 | len_full = 0; |
| 1035 | require_data = true; |
| 1036 | encode = false; |
| 1037 | iter = 0; |
| 1038 | arg = 0; |
| 1039 | do { |
| 1040 | /* NOTE: we don't ever want to trust this value for anything |
| 1041 | * serious, but the audit record format insists we |
| 1042 | * provide an argument length for really long arguments, |
| 1043 | * e.g. > MAX_EXECVE_AUDIT_LEN, so we have no choice but |
| 1044 | * to use strncpy_from_user() to obtain this value for |
| 1045 | * recording in the log, although we don't use it |
| 1046 | * anywhere here to avoid a double-fetch problem */ |
| 1047 | if (len_full == 0) |
| 1048 | len_full = strnlen_user(p, MAX_ARG_STRLEN) - 1; |
| 1049 | |
| 1050 | /* read more data from userspace */ |
| 1051 | if (require_data) { |
| 1052 | /* can we make more room in the buffer? */ |
| 1053 | if (buf != buf_head) { |
| 1054 | memmove(buf_head, buf, len_buf); |
| 1055 | buf = buf_head; |
| 1056 | } |
| 1057 | |
| 1058 | /* fetch as much as we can of the argument */ |
| 1059 | len_tmp = strncpy_from_user(&buf_head[len_buf], p, |
| 1060 | len_max - len_buf); |
| 1061 | if (len_tmp == -EFAULT) { |
| 1062 | /* unable to copy from userspace */ |
| 1063 | send_sig(SIGKILL, current, 0); |
| 1064 | goto out; |
| 1065 | } else if (len_tmp == (len_max - len_buf)) { |
| 1066 | /* buffer is not large enough */ |
| 1067 | require_data = true; |
| 1068 | /* NOTE: if we are going to span multiple |
| 1069 | * buffers force the encoding so we stand |
| 1070 | * a chance at a sane len_full value and |
| 1071 | * consistent record encoding */ |
| 1072 | encode = true; |
| 1073 | len_full = len_full * 2; |
| 1074 | p += len_tmp; |
| 1075 | } else { |
| 1076 | require_data = false; |
| 1077 | if (!encode) |
| 1078 | encode = audit_string_contains_control( |
| 1079 | buf, len_tmp); |
| 1080 | /* try to use a trusted value for len_full */ |
| 1081 | if (len_full < len_max) |
| 1082 | len_full = (encode ? |
| 1083 | len_tmp * 2 : len_tmp); |
| 1084 | p += len_tmp + 1; |
| 1085 | } |
| 1086 | len_buf += len_tmp; |
| 1087 | buf_head[len_buf] = '\0'; |
| 1088 | |
| 1089 | /* length of the buffer in the audit record? */ |
| 1090 | len_abuf = (encode ? len_buf * 2 : len_buf + 2); |
| 1091 | } |
| 1092 | |
| 1093 | /* write as much as we can to the audit log */ |
| 1094 | if (len_buf > 0) { |
| 1095 | /* NOTE: some magic numbers here - basically if we |
| 1096 | * can't fit a reasonable amount of data into the |
| 1097 | * existing audit buffer, flush it and start with |
| 1098 | * a new buffer */ |
| 1099 | if ((sizeof(abuf) + 8) > len_rem) { |
| 1100 | len_rem = len_max; |
| 1101 | audit_log_end(*ab); |
| 1102 | *ab = audit_log_start(context, |
| 1103 | GFP_KERNEL, AUDIT_EXECVE); |
| 1104 | if (!*ab) |
| 1105 | goto out; |
| 1106 | } |
| 1107 | |
| 1108 | /* create the non-arg portion of the arg record */ |
| 1109 | len_tmp = 0; |
| 1110 | if (require_data || (iter > 0) || |
| 1111 | ((len_abuf + sizeof(abuf)) > len_rem)) { |
| 1112 | if (iter == 0) { |
| 1113 | len_tmp += snprintf(&abuf[len_tmp], |
| 1114 | sizeof(abuf) - len_tmp, |
| 1115 | " a%d_len=%lu", |
| 1116 | arg, len_full); |
| 1117 | } |
| 1118 | len_tmp += snprintf(&abuf[len_tmp], |
| 1119 | sizeof(abuf) - len_tmp, |
| 1120 | " a%d[%d]=", arg, iter++); |
| 1121 | } else |
| 1122 | len_tmp += snprintf(&abuf[len_tmp], |
| 1123 | sizeof(abuf) - len_tmp, |
| 1124 | " a%d=", arg); |
| 1125 | WARN_ON(len_tmp >= sizeof(abuf)); |
| 1126 | abuf[sizeof(abuf) - 1] = '\0'; |
| 1127 | |
| 1128 | /* log the arg in the audit record */ |
| 1129 | audit_log_format(*ab, "%s", abuf); |
| 1130 | len_rem -= len_tmp; |
| 1131 | len_tmp = len_buf; |
| 1132 | if (encode) { |
| 1133 | if (len_abuf > len_rem) |
| 1134 | len_tmp = len_rem / 2; /* encoding */ |
| 1135 | audit_log_n_hex(*ab, buf, len_tmp); |
| 1136 | len_rem -= len_tmp * 2; |
| 1137 | len_abuf -= len_tmp * 2; |
| 1138 | } else { |
| 1139 | if (len_abuf > len_rem) |
| 1140 | len_tmp = len_rem - 2; /* quotes */ |
| 1141 | audit_log_n_string(*ab, buf, len_tmp); |
| 1142 | len_rem -= len_tmp + 2; |
| 1143 | /* don't subtract the "2" because we still need |
| 1144 | * to add quotes to the remaining string */ |
| 1145 | len_abuf -= len_tmp; |
| 1146 | } |
| 1147 | len_buf -= len_tmp; |
| 1148 | buf += len_tmp; |
| 1149 | } |
| 1150 | |
| 1151 | /* ready to move to the next argument? */ |
| 1152 | if ((len_buf == 0) && !require_data) { |
| 1153 | arg++; |
| 1154 | iter = 0; |
| 1155 | len_full = 0; |
| 1156 | require_data = true; |
| 1157 | encode = false; |
| 1158 | } |
| 1159 | } while (arg < context->execve.argc); |
| 1160 | |
| 1161 | /* NOTE: the caller handles the final audit_log_end() call */ |
| 1162 | |
| 1163 | out: |
| 1164 | kfree(buf_head); |
| 1165 | } |
| 1166 | |
| 1167 | static void show_special(struct audit_context *context, int *call_panic) |
| 1168 | { |
| 1169 | struct audit_buffer *ab; |
| 1170 | int i; |
| 1171 | |
| 1172 | ab = audit_log_start(context, GFP_KERNEL, context->type); |
| 1173 | if (!ab) |
| 1174 | return; |
| 1175 | |
| 1176 | switch (context->type) { |
| 1177 | case AUDIT_SOCKETCALL: { |
| 1178 | int nargs = context->socketcall.nargs; |
| 1179 | audit_log_format(ab, "nargs=%d", nargs); |
| 1180 | for (i = 0; i < nargs; i++) |
| 1181 | audit_log_format(ab, " a%d=%lx", i, |
| 1182 | context->socketcall.args[i]); |
| 1183 | break; } |
| 1184 | case AUDIT_IPC: { |
| 1185 | u32 osid = context->ipc.osid; |
| 1186 | |
| 1187 | audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho", |
| 1188 | from_kuid(&init_user_ns, context->ipc.uid), |
| 1189 | from_kgid(&init_user_ns, context->ipc.gid), |
| 1190 | context->ipc.mode); |
| 1191 | if (osid) { |
| 1192 | char *ctx = NULL; |
| 1193 | u32 len; |
| 1194 | if (security_secid_to_secctx(osid, &ctx, &len)) { |
| 1195 | audit_log_format(ab, " osid=%u", osid); |
| 1196 | *call_panic = 1; |
| 1197 | } else { |
| 1198 | audit_log_format(ab, " obj=%s", ctx); |
| 1199 | security_release_secctx(ctx, len); |
| 1200 | } |
| 1201 | } |
| 1202 | if (context->ipc.has_perm) { |
| 1203 | audit_log_end(ab); |
| 1204 | ab = audit_log_start(context, GFP_KERNEL, |
| 1205 | AUDIT_IPC_SET_PERM); |
| 1206 | if (unlikely(!ab)) |
| 1207 | return; |
| 1208 | audit_log_format(ab, |
| 1209 | "qbytes=%lx ouid=%u ogid=%u mode=%#ho", |
| 1210 | context->ipc.qbytes, |
| 1211 | context->ipc.perm_uid, |
| 1212 | context->ipc.perm_gid, |
| 1213 | context->ipc.perm_mode); |
| 1214 | } |
| 1215 | break; } |
| 1216 | case AUDIT_MQ_OPEN: { |
| 1217 | audit_log_format(ab, |
| 1218 | "oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld " |
| 1219 | "mq_msgsize=%ld mq_curmsgs=%ld", |
| 1220 | context->mq_open.oflag, context->mq_open.mode, |
| 1221 | context->mq_open.attr.mq_flags, |
| 1222 | context->mq_open.attr.mq_maxmsg, |
| 1223 | context->mq_open.attr.mq_msgsize, |
| 1224 | context->mq_open.attr.mq_curmsgs); |
| 1225 | break; } |
| 1226 | case AUDIT_MQ_SENDRECV: { |
| 1227 | audit_log_format(ab, |
| 1228 | "mqdes=%d msg_len=%zd msg_prio=%u " |
| 1229 | "abs_timeout_sec=%ld abs_timeout_nsec=%ld", |
| 1230 | context->mq_sendrecv.mqdes, |
| 1231 | context->mq_sendrecv.msg_len, |
| 1232 | context->mq_sendrecv.msg_prio, |
| 1233 | context->mq_sendrecv.abs_timeout.tv_sec, |
| 1234 | context->mq_sendrecv.abs_timeout.tv_nsec); |
| 1235 | break; } |
| 1236 | case AUDIT_MQ_NOTIFY: { |
| 1237 | audit_log_format(ab, "mqdes=%d sigev_signo=%d", |
| 1238 | context->mq_notify.mqdes, |
| 1239 | context->mq_notify.sigev_signo); |
| 1240 | break; } |
| 1241 | case AUDIT_MQ_GETSETATTR: { |
| 1242 | struct mq_attr *attr = &context->mq_getsetattr.mqstat; |
| 1243 | audit_log_format(ab, |
| 1244 | "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld " |
| 1245 | "mq_curmsgs=%ld ", |
| 1246 | context->mq_getsetattr.mqdes, |
| 1247 | attr->mq_flags, attr->mq_maxmsg, |
| 1248 | attr->mq_msgsize, attr->mq_curmsgs); |
| 1249 | break; } |
| 1250 | case AUDIT_CAPSET: { |
| 1251 | audit_log_format(ab, "pid=%d", context->capset.pid); |
| 1252 | audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable); |
| 1253 | audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted); |
| 1254 | audit_log_cap(ab, "cap_pe", &context->capset.cap.effective); |
| 1255 | break; } |
| 1256 | case AUDIT_MMAP: { |
| 1257 | audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd, |
| 1258 | context->mmap.flags); |
| 1259 | break; } |
| 1260 | case AUDIT_EXECVE: { |
| 1261 | audit_log_execve_info(context, &ab); |
| 1262 | break; } |
| 1263 | } |
| 1264 | audit_log_end(ab); |
| 1265 | } |
| 1266 | |
| 1267 | static inline int audit_proctitle_rtrim(char *proctitle, int len) |
| 1268 | { |
| 1269 | char *end = proctitle + len - 1; |
| 1270 | while (end > proctitle && !isprint(*end)) |
| 1271 | end--; |
| 1272 | |
| 1273 | /* catch the case where proctitle is only 1 non-print character */ |
| 1274 | len = end - proctitle + 1; |
| 1275 | len -= isprint(proctitle[len-1]) == 0; |
| 1276 | return len; |
| 1277 | } |
| 1278 | |
| 1279 | static void audit_log_proctitle(struct task_struct *tsk, |
| 1280 | struct audit_context *context) |
| 1281 | { |
| 1282 | int res; |
| 1283 | char *buf; |
| 1284 | char *msg = "(null)"; |
| 1285 | int len = strlen(msg); |
| 1286 | struct audit_buffer *ab; |
| 1287 | |
| 1288 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE); |
| 1289 | if (!ab) |
| 1290 | return; /* audit_panic or being filtered */ |
| 1291 | |
| 1292 | audit_log_format(ab, "proctitle="); |
| 1293 | |
| 1294 | /* Not cached */ |
| 1295 | if (!context->proctitle.value) { |
| 1296 | buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL); |
| 1297 | if (!buf) |
| 1298 | goto out; |
| 1299 | /* Historically called this from procfs naming */ |
| 1300 | res = get_cmdline(tsk, buf, MAX_PROCTITLE_AUDIT_LEN); |
| 1301 | if (res == 0) { |
| 1302 | kfree(buf); |
| 1303 | goto out; |
| 1304 | } |
| 1305 | res = audit_proctitle_rtrim(buf, res); |
| 1306 | if (res == 0) { |
| 1307 | kfree(buf); |
| 1308 | goto out; |
| 1309 | } |
| 1310 | context->proctitle.value = buf; |
| 1311 | context->proctitle.len = res; |
| 1312 | } |
| 1313 | msg = context->proctitle.value; |
| 1314 | len = context->proctitle.len; |
| 1315 | out: |
| 1316 | audit_log_n_untrustedstring(ab, msg, len); |
| 1317 | audit_log_end(ab); |
| 1318 | } |
| 1319 | |
| 1320 | static void audit_log_exit(struct audit_context *context, struct task_struct *tsk) |
| 1321 | { |
| 1322 | int i, call_panic = 0; |
| 1323 | struct audit_buffer *ab; |
| 1324 | struct audit_aux_data *aux; |
| 1325 | struct audit_names *n; |
| 1326 | |
| 1327 | /* tsk == current */ |
| 1328 | context->personality = tsk->personality; |
| 1329 | |
| 1330 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); |
| 1331 | if (!ab) |
| 1332 | return; /* audit_panic has been called */ |
| 1333 | audit_log_format(ab, "arch=%x syscall=%d", |
| 1334 | context->arch, context->major); |
| 1335 | if (context->personality != PER_LINUX) |
| 1336 | audit_log_format(ab, " per=%lx", context->personality); |
| 1337 | if (context->return_valid) |
| 1338 | audit_log_format(ab, " success=%s exit=%ld", |
| 1339 | (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", |
| 1340 | context->return_code); |
| 1341 | |
| 1342 | audit_log_format(ab, |
| 1343 | " a0=%lx a1=%lx a2=%lx a3=%lx items=%d", |
| 1344 | context->argv[0], |
| 1345 | context->argv[1], |
| 1346 | context->argv[2], |
| 1347 | context->argv[3], |
| 1348 | context->name_count); |
| 1349 | |
| 1350 | audit_log_task_info(ab, tsk); |
| 1351 | audit_log_key(ab, context->filterkey); |
| 1352 | audit_log_end(ab); |
| 1353 | |
| 1354 | for (aux = context->aux; aux; aux = aux->next) { |
| 1355 | |
| 1356 | ab = audit_log_start(context, GFP_KERNEL, aux->type); |
| 1357 | if (!ab) |
| 1358 | continue; /* audit_panic has been called */ |
| 1359 | |
| 1360 | switch (aux->type) { |
| 1361 | |
| 1362 | case AUDIT_BPRM_FCAPS: { |
| 1363 | struct audit_aux_data_bprm_fcaps *axs = (void *)aux; |
| 1364 | audit_log_format(ab, "fver=%x", axs->fcap_ver); |
| 1365 | audit_log_cap(ab, "fp", &axs->fcap.permitted); |
| 1366 | audit_log_cap(ab, "fi", &axs->fcap.inheritable); |
| 1367 | audit_log_format(ab, " fe=%d", axs->fcap.fE); |
| 1368 | audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted); |
| 1369 | audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable); |
| 1370 | audit_log_cap(ab, "old_pe", &axs->old_pcap.effective); |
| 1371 | audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted); |
| 1372 | audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable); |
| 1373 | audit_log_cap(ab, "new_pe", &axs->new_pcap.effective); |
| 1374 | break; } |
| 1375 | |
| 1376 | } |
| 1377 | audit_log_end(ab); |
| 1378 | } |
| 1379 | |
| 1380 | if (context->type) |
| 1381 | show_special(context, &call_panic); |
| 1382 | |
| 1383 | if (context->fds[0] >= 0) { |
| 1384 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR); |
| 1385 | if (ab) { |
| 1386 | audit_log_format(ab, "fd0=%d fd1=%d", |
| 1387 | context->fds[0], context->fds[1]); |
| 1388 | audit_log_end(ab); |
| 1389 | } |
| 1390 | } |
| 1391 | |
| 1392 | if (context->sockaddr_len) { |
| 1393 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR); |
| 1394 | if (ab) { |
| 1395 | audit_log_format(ab, "saddr="); |
| 1396 | audit_log_n_hex(ab, (void *)context->sockaddr, |
| 1397 | context->sockaddr_len); |
| 1398 | audit_log_end(ab); |
| 1399 | } |
| 1400 | } |
| 1401 | |
| 1402 | for (aux = context->aux_pids; aux; aux = aux->next) { |
| 1403 | struct audit_aux_data_pids *axs = (void *)aux; |
| 1404 | |
| 1405 | for (i = 0; i < axs->pid_count; i++) |
| 1406 | if (audit_log_pid_context(context, axs->target_pid[i], |
| 1407 | axs->target_auid[i], |
| 1408 | axs->target_uid[i], |
| 1409 | axs->target_sessionid[i], |
| 1410 | axs->target_sid[i], |
| 1411 | axs->target_comm[i])) |
| 1412 | call_panic = 1; |
| 1413 | } |
| 1414 | |
| 1415 | if (context->target_pid && |
| 1416 | audit_log_pid_context(context, context->target_pid, |
| 1417 | context->target_auid, context->target_uid, |
| 1418 | context->target_sessionid, |
| 1419 | context->target_sid, context->target_comm)) |
| 1420 | call_panic = 1; |
| 1421 | |
| 1422 | if (context->pwd.dentry && context->pwd.mnt) { |
| 1423 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); |
| 1424 | if (ab) { |
| 1425 | audit_log_d_path(ab, " cwd=", &context->pwd); |
| 1426 | audit_log_end(ab); |
| 1427 | } |
| 1428 | } |
| 1429 | |
| 1430 | i = 0; |
| 1431 | list_for_each_entry(n, &context->names_list, list) { |
| 1432 | if (n->hidden) |
| 1433 | continue; |
| 1434 | audit_log_name(context, n, NULL, i++, &call_panic); |
| 1435 | } |
| 1436 | |
| 1437 | audit_log_proctitle(tsk, context); |
| 1438 | |
| 1439 | /* Send end of event record to help user space know we are finished */ |
| 1440 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); |
| 1441 | if (ab) |
| 1442 | audit_log_end(ab); |
| 1443 | if (call_panic) |
| 1444 | audit_panic("error converting sid to string"); |
| 1445 | } |
| 1446 | |
| 1447 | /** |
| 1448 | * audit_free - free a per-task audit context |
| 1449 | * @tsk: task whose audit context block to free |
| 1450 | * |
| 1451 | * Called from copy_process and do_exit |
| 1452 | */ |
| 1453 | void __audit_free(struct task_struct *tsk) |
| 1454 | { |
| 1455 | struct audit_context *context; |
| 1456 | |
| 1457 | context = audit_take_context(tsk, 0, 0); |
| 1458 | if (!context) |
| 1459 | return; |
| 1460 | |
| 1461 | /* Check for system calls that do not go through the exit |
| 1462 | * function (e.g., exit_group), then free context block. |
| 1463 | * We use GFP_ATOMIC here because we might be doing this |
| 1464 | * in the context of the idle thread */ |
| 1465 | /* that can happen only if we are called from do_exit() */ |
| 1466 | if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) |
| 1467 | audit_log_exit(context, tsk); |
| 1468 | if (!list_empty(&context->killed_trees)) |
| 1469 | audit_kill_trees(&context->killed_trees); |
| 1470 | |
| 1471 | audit_free_context(context); |
| 1472 | } |
| 1473 | |
| 1474 | /** |
| 1475 | * audit_syscall_entry - fill in an audit record at syscall entry |
| 1476 | * @major: major syscall type (function) |
| 1477 | * @a1: additional syscall register 1 |
| 1478 | * @a2: additional syscall register 2 |
| 1479 | * @a3: additional syscall register 3 |
| 1480 | * @a4: additional syscall register 4 |
| 1481 | * |
| 1482 | * Fill in audit context at syscall entry. This only happens if the |
| 1483 | * audit context was created when the task was created and the state or |
| 1484 | * filters demand the audit context be built. If the state from the |
| 1485 | * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, |
| 1486 | * then the record will be written at syscall exit time (otherwise, it |
| 1487 | * will only be written if another part of the kernel requests that it |
| 1488 | * be written). |
| 1489 | */ |
| 1490 | void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2, |
| 1491 | unsigned long a3, unsigned long a4) |
| 1492 | { |
| 1493 | struct task_struct *tsk = current; |
| 1494 | struct audit_context *context = tsk->audit_context; |
| 1495 | enum audit_state state; |
| 1496 | |
| 1497 | if (!context) |
| 1498 | return; |
| 1499 | |
| 1500 | BUG_ON(context->in_syscall || context->name_count); |
| 1501 | |
| 1502 | if (!audit_enabled) |
| 1503 | return; |
| 1504 | |
| 1505 | context->arch = syscall_get_arch(); |
| 1506 | context->major = major; |
| 1507 | context->argv[0] = a1; |
| 1508 | context->argv[1] = a2; |
| 1509 | context->argv[2] = a3; |
| 1510 | context->argv[3] = a4; |
| 1511 | |
| 1512 | state = context->state; |
| 1513 | context->dummy = !audit_n_rules; |
| 1514 | if (!context->dummy && state == AUDIT_BUILD_CONTEXT) { |
| 1515 | context->prio = 0; |
| 1516 | state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]); |
| 1517 | } |
| 1518 | if (state == AUDIT_DISABLED) |
| 1519 | return; |
| 1520 | |
| 1521 | context->serial = 0; |
| 1522 | context->ctime = CURRENT_TIME; |
| 1523 | context->in_syscall = 1; |
| 1524 | context->current_state = state; |
| 1525 | context->ppid = 0; |
| 1526 | } |
| 1527 | |
| 1528 | /** |
| 1529 | * audit_syscall_exit - deallocate audit context after a system call |
| 1530 | * @success: success value of the syscall |
| 1531 | * @return_code: return value of the syscall |
| 1532 | * |
| 1533 | * Tear down after system call. If the audit context has been marked as |
| 1534 | * auditable (either because of the AUDIT_RECORD_CONTEXT state from |
| 1535 | * filtering, or because some other part of the kernel wrote an audit |
| 1536 | * message), then write out the syscall information. In call cases, |
| 1537 | * free the names stored from getname(). |
| 1538 | */ |
| 1539 | void __audit_syscall_exit(int success, long return_code) |
| 1540 | { |
| 1541 | struct task_struct *tsk = current; |
| 1542 | struct audit_context *context; |
| 1543 | |
| 1544 | if (success) |
| 1545 | success = AUDITSC_SUCCESS; |
| 1546 | else |
| 1547 | success = AUDITSC_FAILURE; |
| 1548 | |
| 1549 | context = audit_take_context(tsk, success, return_code); |
| 1550 | if (!context) |
| 1551 | return; |
| 1552 | |
| 1553 | if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) |
| 1554 | audit_log_exit(context, tsk); |
| 1555 | |
| 1556 | context->in_syscall = 0; |
| 1557 | context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; |
| 1558 | |
| 1559 | if (!list_empty(&context->killed_trees)) |
| 1560 | audit_kill_trees(&context->killed_trees); |
| 1561 | |
| 1562 | audit_free_names(context); |
| 1563 | unroll_tree_refs(context, NULL, 0); |
| 1564 | audit_free_aux(context); |
| 1565 | context->aux = NULL; |
| 1566 | context->aux_pids = NULL; |
| 1567 | context->target_pid = 0; |
| 1568 | context->target_sid = 0; |
| 1569 | context->sockaddr_len = 0; |
| 1570 | context->type = 0; |
| 1571 | context->fds[0] = -1; |
| 1572 | if (context->state != AUDIT_RECORD_CONTEXT) { |
| 1573 | kfree(context->filterkey); |
| 1574 | context->filterkey = NULL; |
| 1575 | } |
| 1576 | tsk->audit_context = context; |
| 1577 | } |
| 1578 | |
| 1579 | static inline void handle_one(const struct inode *inode) |
| 1580 | { |
| 1581 | #ifdef CONFIG_AUDIT_TREE |
| 1582 | struct audit_context *context; |
| 1583 | struct audit_tree_refs *p; |
| 1584 | struct audit_chunk *chunk; |
| 1585 | int count; |
| 1586 | if (likely(hlist_empty(&inode->i_fsnotify_marks))) |
| 1587 | return; |
| 1588 | context = current->audit_context; |
| 1589 | p = context->trees; |
| 1590 | count = context->tree_count; |
| 1591 | rcu_read_lock(); |
| 1592 | chunk = audit_tree_lookup(inode); |
| 1593 | rcu_read_unlock(); |
| 1594 | if (!chunk) |
| 1595 | return; |
| 1596 | if (likely(put_tree_ref(context, chunk))) |
| 1597 | return; |
| 1598 | if (unlikely(!grow_tree_refs(context))) { |
| 1599 | pr_warn("out of memory, audit has lost a tree reference\n"); |
| 1600 | audit_set_auditable(context); |
| 1601 | audit_put_chunk(chunk); |
| 1602 | unroll_tree_refs(context, p, count); |
| 1603 | return; |
| 1604 | } |
| 1605 | put_tree_ref(context, chunk); |
| 1606 | #endif |
| 1607 | } |
| 1608 | |
| 1609 | static void handle_path(const struct dentry *dentry) |
| 1610 | { |
| 1611 | #ifdef CONFIG_AUDIT_TREE |
| 1612 | struct audit_context *context; |
| 1613 | struct audit_tree_refs *p; |
| 1614 | const struct dentry *d, *parent; |
| 1615 | struct audit_chunk *drop; |
| 1616 | unsigned long seq; |
| 1617 | int count; |
| 1618 | |
| 1619 | context = current->audit_context; |
| 1620 | p = context->trees; |
| 1621 | count = context->tree_count; |
| 1622 | retry: |
| 1623 | drop = NULL; |
| 1624 | d = dentry; |
| 1625 | rcu_read_lock(); |
| 1626 | seq = read_seqbegin(&rename_lock); |
| 1627 | for(;;) { |
| 1628 | struct inode *inode = d_backing_inode(d); |
| 1629 | if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) { |
| 1630 | struct audit_chunk *chunk; |
| 1631 | chunk = audit_tree_lookup(inode); |
| 1632 | if (chunk) { |
| 1633 | if (unlikely(!put_tree_ref(context, chunk))) { |
| 1634 | drop = chunk; |
| 1635 | break; |
| 1636 | } |
| 1637 | } |
| 1638 | } |
| 1639 | parent = d->d_parent; |
| 1640 | if (parent == d) |
| 1641 | break; |
| 1642 | d = parent; |
| 1643 | } |
| 1644 | if (unlikely(read_seqretry(&rename_lock, seq) || drop)) { /* in this order */ |
| 1645 | rcu_read_unlock(); |
| 1646 | if (!drop) { |
| 1647 | /* just a race with rename */ |
| 1648 | unroll_tree_refs(context, p, count); |
| 1649 | goto retry; |
| 1650 | } |
| 1651 | audit_put_chunk(drop); |
| 1652 | if (grow_tree_refs(context)) { |
| 1653 | /* OK, got more space */ |
| 1654 | unroll_tree_refs(context, p, count); |
| 1655 | goto retry; |
| 1656 | } |
| 1657 | /* too bad */ |
| 1658 | pr_warn("out of memory, audit has lost a tree reference\n"); |
| 1659 | unroll_tree_refs(context, p, count); |
| 1660 | audit_set_auditable(context); |
| 1661 | return; |
| 1662 | } |
| 1663 | rcu_read_unlock(); |
| 1664 | #endif |
| 1665 | } |
| 1666 | |
| 1667 | static struct audit_names *audit_alloc_name(struct audit_context *context, |
| 1668 | unsigned char type) |
| 1669 | { |
| 1670 | struct audit_names *aname; |
| 1671 | |
| 1672 | if (context->name_count < AUDIT_NAMES) { |
| 1673 | aname = &context->preallocated_names[context->name_count]; |
| 1674 | memset(aname, 0, sizeof(*aname)); |
| 1675 | } else { |
| 1676 | aname = kzalloc(sizeof(*aname), GFP_NOFS); |
| 1677 | if (!aname) |
| 1678 | return NULL; |
| 1679 | aname->should_free = true; |
| 1680 | } |
| 1681 | |
| 1682 | aname->ino = AUDIT_INO_UNSET; |
| 1683 | aname->type = type; |
| 1684 | list_add_tail(&aname->list, &context->names_list); |
| 1685 | |
| 1686 | context->name_count++; |
| 1687 | return aname; |
| 1688 | } |
| 1689 | |
| 1690 | /** |
| 1691 | * audit_reusename - fill out filename with info from existing entry |
| 1692 | * @uptr: userland ptr to pathname |
| 1693 | * |
| 1694 | * Search the audit_names list for the current audit context. If there is an |
| 1695 | * existing entry with a matching "uptr" then return the filename |
| 1696 | * associated with that audit_name. If not, return NULL. |
| 1697 | */ |
| 1698 | struct filename * |
| 1699 | __audit_reusename(const __user char *uptr) |
| 1700 | { |
| 1701 | struct audit_context *context = current->audit_context; |
| 1702 | struct audit_names *n; |
| 1703 | |
| 1704 | list_for_each_entry(n, &context->names_list, list) { |
| 1705 | if (!n->name) |
| 1706 | continue; |
| 1707 | if (n->name->uptr == uptr) { |
| 1708 | n->name->refcnt++; |
| 1709 | return n->name; |
| 1710 | } |
| 1711 | } |
| 1712 | return NULL; |
| 1713 | } |
| 1714 | |
| 1715 | /** |
| 1716 | * audit_getname - add a name to the list |
| 1717 | * @name: name to add |
| 1718 | * |
| 1719 | * Add a name to the list of audit names for this context. |
| 1720 | * Called from fs/namei.c:getname(). |
| 1721 | */ |
| 1722 | void __audit_getname(struct filename *name) |
| 1723 | { |
| 1724 | struct audit_context *context = current->audit_context; |
| 1725 | struct audit_names *n; |
| 1726 | |
| 1727 | if (!context->in_syscall) |
| 1728 | return; |
| 1729 | |
| 1730 | n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); |
| 1731 | if (!n) |
| 1732 | return; |
| 1733 | |
| 1734 | n->name = name; |
| 1735 | n->name_len = AUDIT_NAME_FULL; |
| 1736 | name->aname = n; |
| 1737 | name->refcnt++; |
| 1738 | |
| 1739 | if (!context->pwd.dentry) |
| 1740 | get_fs_pwd(current->fs, &context->pwd); |
| 1741 | } |
| 1742 | |
| 1743 | /** |
| 1744 | * __audit_inode - store the inode and device from a lookup |
| 1745 | * @name: name being audited |
| 1746 | * @dentry: dentry being audited |
| 1747 | * @flags: attributes for this particular entry |
| 1748 | */ |
| 1749 | void __audit_inode(struct filename *name, const struct dentry *dentry, |
| 1750 | unsigned int flags) |
| 1751 | { |
| 1752 | struct audit_context *context = current->audit_context; |
| 1753 | const struct inode *inode = d_backing_inode(dentry); |
| 1754 | struct audit_names *n; |
| 1755 | bool parent = flags & AUDIT_INODE_PARENT; |
| 1756 | |
| 1757 | if (!context->in_syscall) |
| 1758 | return; |
| 1759 | |
| 1760 | if (!name) |
| 1761 | goto out_alloc; |
| 1762 | |
| 1763 | /* |
| 1764 | * If we have a pointer to an audit_names entry already, then we can |
| 1765 | * just use it directly if the type is correct. |
| 1766 | */ |
| 1767 | n = name->aname; |
| 1768 | if (n) { |
| 1769 | if (parent) { |
| 1770 | if (n->type == AUDIT_TYPE_PARENT || |
| 1771 | n->type == AUDIT_TYPE_UNKNOWN) |
| 1772 | goto out; |
| 1773 | } else { |
| 1774 | if (n->type != AUDIT_TYPE_PARENT) |
| 1775 | goto out; |
| 1776 | } |
| 1777 | } |
| 1778 | |
| 1779 | list_for_each_entry_reverse(n, &context->names_list, list) { |
| 1780 | if (n->ino) { |
| 1781 | /* valid inode number, use that for the comparison */ |
| 1782 | if (n->ino != inode->i_ino || |
| 1783 | n->dev != inode->i_sb->s_dev) |
| 1784 | continue; |
| 1785 | } else if (n->name) { |
| 1786 | /* inode number has not been set, check the name */ |
| 1787 | if (strcmp(n->name->name, name->name)) |
| 1788 | continue; |
| 1789 | } else |
| 1790 | /* no inode and no name (?!) ... this is odd ... */ |
| 1791 | continue; |
| 1792 | |
| 1793 | /* match the correct record type */ |
| 1794 | if (parent) { |
| 1795 | if (n->type == AUDIT_TYPE_PARENT || |
| 1796 | n->type == AUDIT_TYPE_UNKNOWN) |
| 1797 | goto out; |
| 1798 | } else { |
| 1799 | if (n->type != AUDIT_TYPE_PARENT) |
| 1800 | goto out; |
| 1801 | } |
| 1802 | } |
| 1803 | |
| 1804 | out_alloc: |
| 1805 | /* unable to find an entry with both a matching name and type */ |
| 1806 | n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); |
| 1807 | if (!n) |
| 1808 | return; |
| 1809 | if (name) { |
| 1810 | n->name = name; |
| 1811 | name->refcnt++; |
| 1812 | } |
| 1813 | |
| 1814 | out: |
| 1815 | if (parent) { |
| 1816 | n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL; |
| 1817 | n->type = AUDIT_TYPE_PARENT; |
| 1818 | if (flags & AUDIT_INODE_HIDDEN) |
| 1819 | n->hidden = true; |
| 1820 | } else { |
| 1821 | n->name_len = AUDIT_NAME_FULL; |
| 1822 | n->type = AUDIT_TYPE_NORMAL; |
| 1823 | } |
| 1824 | handle_path(dentry); |
| 1825 | audit_copy_inode(n, dentry, inode); |
| 1826 | } |
| 1827 | |
| 1828 | void __audit_file(const struct file *file) |
| 1829 | { |
| 1830 | __audit_inode(NULL, file->f_path.dentry, 0); |
| 1831 | } |
| 1832 | |
| 1833 | /** |
| 1834 | * __audit_inode_child - collect inode info for created/removed objects |
| 1835 | * @parent: inode of dentry parent |
| 1836 | * @dentry: dentry being audited |
| 1837 | * @type: AUDIT_TYPE_* value that we're looking for |
| 1838 | * |
| 1839 | * For syscalls that create or remove filesystem objects, audit_inode |
| 1840 | * can only collect information for the filesystem object's parent. |
| 1841 | * This call updates the audit context with the child's information. |
| 1842 | * Syscalls that create a new filesystem object must be hooked after |
| 1843 | * the object is created. Syscalls that remove a filesystem object |
| 1844 | * must be hooked prior, in order to capture the target inode during |
| 1845 | * unsuccessful attempts. |
| 1846 | */ |
| 1847 | void __audit_inode_child(const struct inode *parent, |
| 1848 | const struct dentry *dentry, |
| 1849 | const unsigned char type) |
| 1850 | { |
| 1851 | struct audit_context *context = current->audit_context; |
| 1852 | const struct inode *inode = d_backing_inode(dentry); |
| 1853 | const char *dname = dentry->d_name.name; |
| 1854 | struct audit_names *n, *found_parent = NULL, *found_child = NULL; |
| 1855 | |
| 1856 | if (!context->in_syscall) |
| 1857 | return; |
| 1858 | |
| 1859 | if (inode) |
| 1860 | handle_one(inode); |
| 1861 | |
| 1862 | /* look for a parent entry first */ |
| 1863 | list_for_each_entry(n, &context->names_list, list) { |
| 1864 | if (!n->name || |
| 1865 | (n->type != AUDIT_TYPE_PARENT && |
| 1866 | n->type != AUDIT_TYPE_UNKNOWN)) |
| 1867 | continue; |
| 1868 | |
| 1869 | if (n->ino == parent->i_ino && n->dev == parent->i_sb->s_dev && |
| 1870 | !audit_compare_dname_path(dname, |
| 1871 | n->name->name, n->name_len)) { |
| 1872 | if (n->type == AUDIT_TYPE_UNKNOWN) |
| 1873 | n->type = AUDIT_TYPE_PARENT; |
| 1874 | found_parent = n; |
| 1875 | break; |
| 1876 | } |
| 1877 | } |
| 1878 | |
| 1879 | /* is there a matching child entry? */ |
| 1880 | list_for_each_entry(n, &context->names_list, list) { |
| 1881 | /* can only match entries that have a name */ |
| 1882 | if (!n->name || |
| 1883 | (n->type != type && n->type != AUDIT_TYPE_UNKNOWN)) |
| 1884 | continue; |
| 1885 | |
| 1886 | if (!strcmp(dname, n->name->name) || |
| 1887 | !audit_compare_dname_path(dname, n->name->name, |
| 1888 | found_parent ? |
| 1889 | found_parent->name_len : |
| 1890 | AUDIT_NAME_FULL)) { |
| 1891 | if (n->type == AUDIT_TYPE_UNKNOWN) |
| 1892 | n->type = type; |
| 1893 | found_child = n; |
| 1894 | break; |
| 1895 | } |
| 1896 | } |
| 1897 | |
| 1898 | if (!found_parent) { |
| 1899 | /* create a new, "anonymous" parent record */ |
| 1900 | n = audit_alloc_name(context, AUDIT_TYPE_PARENT); |
| 1901 | if (!n) |
| 1902 | return; |
| 1903 | audit_copy_inode(n, NULL, parent); |
| 1904 | } |
| 1905 | |
| 1906 | if (!found_child) { |
| 1907 | found_child = audit_alloc_name(context, type); |
| 1908 | if (!found_child) |
| 1909 | return; |
| 1910 | |
| 1911 | /* Re-use the name belonging to the slot for a matching parent |
| 1912 | * directory. All names for this context are relinquished in |
| 1913 | * audit_free_names() */ |
| 1914 | if (found_parent) { |
| 1915 | found_child->name = found_parent->name; |
| 1916 | found_child->name_len = AUDIT_NAME_FULL; |
| 1917 | found_child->name->refcnt++; |
| 1918 | } |
| 1919 | } |
| 1920 | |
| 1921 | if (inode) |
| 1922 | audit_copy_inode(found_child, dentry, inode); |
| 1923 | else |
| 1924 | found_child->ino = AUDIT_INO_UNSET; |
| 1925 | } |
| 1926 | EXPORT_SYMBOL_GPL(__audit_inode_child); |
| 1927 | |
| 1928 | /** |
| 1929 | * auditsc_get_stamp - get local copies of audit_context values |
| 1930 | * @ctx: audit_context for the task |
| 1931 | * @t: timespec to store time recorded in the audit_context |
| 1932 | * @serial: serial value that is recorded in the audit_context |
| 1933 | * |
| 1934 | * Also sets the context as auditable. |
| 1935 | */ |
| 1936 | int auditsc_get_stamp(struct audit_context *ctx, |
| 1937 | struct timespec *t, unsigned int *serial) |
| 1938 | { |
| 1939 | if (!ctx->in_syscall) |
| 1940 | return 0; |
| 1941 | if (!ctx->serial) |
| 1942 | ctx->serial = audit_serial(); |
| 1943 | t->tv_sec = ctx->ctime.tv_sec; |
| 1944 | t->tv_nsec = ctx->ctime.tv_nsec; |
| 1945 | *serial = ctx->serial; |
| 1946 | if (!ctx->prio) { |
| 1947 | ctx->prio = 1; |
| 1948 | ctx->current_state = AUDIT_RECORD_CONTEXT; |
| 1949 | } |
| 1950 | return 1; |
| 1951 | } |
| 1952 | |
| 1953 | /* global counter which is incremented every time something logs in */ |
| 1954 | static atomic_t session_id = ATOMIC_INIT(0); |
| 1955 | |
| 1956 | static int audit_set_loginuid_perm(kuid_t loginuid) |
| 1957 | { |
| 1958 | /* if we are unset, we don't need privs */ |
| 1959 | if (!audit_loginuid_set(current)) |
| 1960 | return 0; |
| 1961 | /* if AUDIT_FEATURE_LOGINUID_IMMUTABLE means never ever allow a change*/ |
| 1962 | if (is_audit_feature_set(AUDIT_FEATURE_LOGINUID_IMMUTABLE)) |
| 1963 | return -EPERM; |
| 1964 | /* it is set, you need permission */ |
| 1965 | if (!capable(CAP_AUDIT_CONTROL)) |
| 1966 | return -EPERM; |
| 1967 | /* reject if this is not an unset and we don't allow that */ |
| 1968 | if (is_audit_feature_set(AUDIT_FEATURE_ONLY_UNSET_LOGINUID) && uid_valid(loginuid)) |
| 1969 | return -EPERM; |
| 1970 | return 0; |
| 1971 | } |
| 1972 | |
| 1973 | static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid, |
| 1974 | unsigned int oldsessionid, unsigned int sessionid, |
| 1975 | int rc) |
| 1976 | { |
| 1977 | struct audit_buffer *ab; |
| 1978 | uid_t uid, oldloginuid, loginuid; |
| 1979 | |
| 1980 | if (!audit_enabled) |
| 1981 | return; |
| 1982 | |
| 1983 | uid = from_kuid(&init_user_ns, task_uid(current)); |
| 1984 | oldloginuid = from_kuid(&init_user_ns, koldloginuid); |
| 1985 | loginuid = from_kuid(&init_user_ns, kloginuid), |
| 1986 | |
| 1987 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); |
| 1988 | if (!ab) |
| 1989 | return; |
| 1990 | audit_log_format(ab, "pid=%d uid=%u", task_pid_nr(current), uid); |
| 1991 | audit_log_task_context(ab); |
| 1992 | audit_log_format(ab, " old-auid=%u auid=%u old-ses=%u ses=%u res=%d", |
| 1993 | oldloginuid, loginuid, oldsessionid, sessionid, !rc); |
| 1994 | audit_log_end(ab); |
| 1995 | } |
| 1996 | |
| 1997 | /** |
| 1998 | * audit_set_loginuid - set current task's audit_context loginuid |
| 1999 | * @loginuid: loginuid value |
| 2000 | * |
| 2001 | * Returns 0. |
| 2002 | * |
| 2003 | * Called (set) from fs/proc/base.c::proc_loginuid_write(). |
| 2004 | */ |
| 2005 | int audit_set_loginuid(kuid_t loginuid) |
| 2006 | { |
| 2007 | struct task_struct *task = current; |
| 2008 | unsigned int oldsessionid, sessionid = (unsigned int)-1; |
| 2009 | kuid_t oldloginuid; |
| 2010 | int rc; |
| 2011 | |
| 2012 | oldloginuid = audit_get_loginuid(current); |
| 2013 | oldsessionid = audit_get_sessionid(current); |
| 2014 | |
| 2015 | rc = audit_set_loginuid_perm(loginuid); |
| 2016 | if (rc) |
| 2017 | goto out; |
| 2018 | |
| 2019 | /* are we setting or clearing? */ |
| 2020 | if (uid_valid(loginuid)) |
| 2021 | sessionid = (unsigned int)atomic_inc_return(&session_id); |
| 2022 | |
| 2023 | task->sessionid = sessionid; |
| 2024 | task->loginuid = loginuid; |
| 2025 | out: |
| 2026 | audit_log_set_loginuid(oldloginuid, loginuid, oldsessionid, sessionid, rc); |
| 2027 | return rc; |
| 2028 | } |
| 2029 | |
| 2030 | /** |
| 2031 | * __audit_mq_open - record audit data for a POSIX MQ open |
| 2032 | * @oflag: open flag |
| 2033 | * @mode: mode bits |
| 2034 | * @attr: queue attributes |
| 2035 | * |
| 2036 | */ |
| 2037 | void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr) |
| 2038 | { |
| 2039 | struct audit_context *context = current->audit_context; |
| 2040 | |
| 2041 | if (attr) |
| 2042 | memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr)); |
| 2043 | else |
| 2044 | memset(&context->mq_open.attr, 0, sizeof(struct mq_attr)); |
| 2045 | |
| 2046 | context->mq_open.oflag = oflag; |
| 2047 | context->mq_open.mode = mode; |
| 2048 | |
| 2049 | context->type = AUDIT_MQ_OPEN; |
| 2050 | } |
| 2051 | |
| 2052 | /** |
| 2053 | * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive |
| 2054 | * @mqdes: MQ descriptor |
| 2055 | * @msg_len: Message length |
| 2056 | * @msg_prio: Message priority |
| 2057 | * @abs_timeout: Message timeout in absolute time |
| 2058 | * |
| 2059 | */ |
| 2060 | void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, |
| 2061 | const struct timespec *abs_timeout) |
| 2062 | { |
| 2063 | struct audit_context *context = current->audit_context; |
| 2064 | struct timespec *p = &context->mq_sendrecv.abs_timeout; |
| 2065 | |
| 2066 | if (abs_timeout) |
| 2067 | memcpy(p, abs_timeout, sizeof(struct timespec)); |
| 2068 | else |
| 2069 | memset(p, 0, sizeof(struct timespec)); |
| 2070 | |
| 2071 | context->mq_sendrecv.mqdes = mqdes; |
| 2072 | context->mq_sendrecv.msg_len = msg_len; |
| 2073 | context->mq_sendrecv.msg_prio = msg_prio; |
| 2074 | |
| 2075 | context->type = AUDIT_MQ_SENDRECV; |
| 2076 | } |
| 2077 | |
| 2078 | /** |
| 2079 | * __audit_mq_notify - record audit data for a POSIX MQ notify |
| 2080 | * @mqdes: MQ descriptor |
| 2081 | * @notification: Notification event |
| 2082 | * |
| 2083 | */ |
| 2084 | |
| 2085 | void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification) |
| 2086 | { |
| 2087 | struct audit_context *context = current->audit_context; |
| 2088 | |
| 2089 | if (notification) |
| 2090 | context->mq_notify.sigev_signo = notification->sigev_signo; |
| 2091 | else |
| 2092 | context->mq_notify.sigev_signo = 0; |
| 2093 | |
| 2094 | context->mq_notify.mqdes = mqdes; |
| 2095 | context->type = AUDIT_MQ_NOTIFY; |
| 2096 | } |
| 2097 | |
| 2098 | /** |
| 2099 | * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute |
| 2100 | * @mqdes: MQ descriptor |
| 2101 | * @mqstat: MQ flags |
| 2102 | * |
| 2103 | */ |
| 2104 | void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) |
| 2105 | { |
| 2106 | struct audit_context *context = current->audit_context; |
| 2107 | context->mq_getsetattr.mqdes = mqdes; |
| 2108 | context->mq_getsetattr.mqstat = *mqstat; |
| 2109 | context->type = AUDIT_MQ_GETSETATTR; |
| 2110 | } |
| 2111 | |
| 2112 | /** |
| 2113 | * audit_ipc_obj - record audit data for ipc object |
| 2114 | * @ipcp: ipc permissions |
| 2115 | * |
| 2116 | */ |
| 2117 | void __audit_ipc_obj(struct kern_ipc_perm *ipcp) |
| 2118 | { |
| 2119 | struct audit_context *context = current->audit_context; |
| 2120 | context->ipc.uid = ipcp->uid; |
| 2121 | context->ipc.gid = ipcp->gid; |
| 2122 | context->ipc.mode = ipcp->mode; |
| 2123 | context->ipc.has_perm = 0; |
| 2124 | security_ipc_getsecid(ipcp, &context->ipc.osid); |
| 2125 | context->type = AUDIT_IPC; |
| 2126 | } |
| 2127 | |
| 2128 | /** |
| 2129 | * audit_ipc_set_perm - record audit data for new ipc permissions |
| 2130 | * @qbytes: msgq bytes |
| 2131 | * @uid: msgq user id |
| 2132 | * @gid: msgq group id |
| 2133 | * @mode: msgq mode (permissions) |
| 2134 | * |
| 2135 | * Called only after audit_ipc_obj(). |
| 2136 | */ |
| 2137 | void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode) |
| 2138 | { |
| 2139 | struct audit_context *context = current->audit_context; |
| 2140 | |
| 2141 | context->ipc.qbytes = qbytes; |
| 2142 | context->ipc.perm_uid = uid; |
| 2143 | context->ipc.perm_gid = gid; |
| 2144 | context->ipc.perm_mode = mode; |
| 2145 | context->ipc.has_perm = 1; |
| 2146 | } |
| 2147 | |
| 2148 | void __audit_bprm(struct linux_binprm *bprm) |
| 2149 | { |
| 2150 | struct audit_context *context = current->audit_context; |
| 2151 | |
| 2152 | context->type = AUDIT_EXECVE; |
| 2153 | context->execve.argc = bprm->argc; |
| 2154 | } |
| 2155 | |
| 2156 | |
| 2157 | /** |
| 2158 | * audit_socketcall - record audit data for sys_socketcall |
| 2159 | * @nargs: number of args, which should not be more than AUDITSC_ARGS. |
| 2160 | * @args: args array |
| 2161 | * |
| 2162 | */ |
| 2163 | int __audit_socketcall(int nargs, unsigned long *args) |
| 2164 | { |
| 2165 | struct audit_context *context = current->audit_context; |
| 2166 | |
| 2167 | if (nargs <= 0 || nargs > AUDITSC_ARGS || !args) |
| 2168 | return -EINVAL; |
| 2169 | context->type = AUDIT_SOCKETCALL; |
| 2170 | context->socketcall.nargs = nargs; |
| 2171 | memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long)); |
| 2172 | return 0; |
| 2173 | } |
| 2174 | |
| 2175 | /** |
| 2176 | * __audit_fd_pair - record audit data for pipe and socketpair |
| 2177 | * @fd1: the first file descriptor |
| 2178 | * @fd2: the second file descriptor |
| 2179 | * |
| 2180 | */ |
| 2181 | void __audit_fd_pair(int fd1, int fd2) |
| 2182 | { |
| 2183 | struct audit_context *context = current->audit_context; |
| 2184 | context->fds[0] = fd1; |
| 2185 | context->fds[1] = fd2; |
| 2186 | } |
| 2187 | |
| 2188 | /** |
| 2189 | * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto |
| 2190 | * @len: data length in user space |
| 2191 | * @a: data address in kernel space |
| 2192 | * |
| 2193 | * Returns 0 for success or NULL context or < 0 on error. |
| 2194 | */ |
| 2195 | int __audit_sockaddr(int len, void *a) |
| 2196 | { |
| 2197 | struct audit_context *context = current->audit_context; |
| 2198 | |
| 2199 | if (!context->sockaddr) { |
| 2200 | void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL); |
| 2201 | if (!p) |
| 2202 | return -ENOMEM; |
| 2203 | context->sockaddr = p; |
| 2204 | } |
| 2205 | |
| 2206 | context->sockaddr_len = len; |
| 2207 | memcpy(context->sockaddr, a, len); |
| 2208 | return 0; |
| 2209 | } |
| 2210 | |
| 2211 | void __audit_ptrace(struct task_struct *t) |
| 2212 | { |
| 2213 | struct audit_context *context = current->audit_context; |
| 2214 | |
| 2215 | context->target_pid = task_pid_nr(t); |
| 2216 | context->target_auid = audit_get_loginuid(t); |
| 2217 | context->target_uid = task_uid(t); |
| 2218 | context->target_sessionid = audit_get_sessionid(t); |
| 2219 | security_task_getsecid(t, &context->target_sid); |
| 2220 | memcpy(context->target_comm, t->comm, TASK_COMM_LEN); |
| 2221 | } |
| 2222 | |
| 2223 | /** |
| 2224 | * audit_signal_info - record signal info for shutting down audit subsystem |
| 2225 | * @sig: signal value |
| 2226 | * @t: task being signaled |
| 2227 | * |
| 2228 | * If the audit subsystem is being terminated, record the task (pid) |
| 2229 | * and uid that is doing that. |
| 2230 | */ |
| 2231 | int __audit_signal_info(int sig, struct task_struct *t) |
| 2232 | { |
| 2233 | struct audit_aux_data_pids *axp; |
| 2234 | struct task_struct *tsk = current; |
| 2235 | struct audit_context *ctx = tsk->audit_context; |
| 2236 | kuid_t uid = current_uid(), t_uid = task_uid(t); |
| 2237 | |
| 2238 | if (audit_pid && t->tgid == audit_pid) { |
| 2239 | if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) { |
| 2240 | audit_sig_pid = task_pid_nr(tsk); |
| 2241 | if (uid_valid(tsk->loginuid)) |
| 2242 | audit_sig_uid = tsk->loginuid; |
| 2243 | else |
| 2244 | audit_sig_uid = uid; |
| 2245 | security_task_getsecid(tsk, &audit_sig_sid); |
| 2246 | } |
| 2247 | if (!audit_signals || audit_dummy_context()) |
| 2248 | return 0; |
| 2249 | } |
| 2250 | |
| 2251 | /* optimize the common case by putting first signal recipient directly |
| 2252 | * in audit_context */ |
| 2253 | if (!ctx->target_pid) { |
| 2254 | ctx->target_pid = task_tgid_nr(t); |
| 2255 | ctx->target_auid = audit_get_loginuid(t); |
| 2256 | ctx->target_uid = t_uid; |
| 2257 | ctx->target_sessionid = audit_get_sessionid(t); |
| 2258 | security_task_getsecid(t, &ctx->target_sid); |
| 2259 | memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); |
| 2260 | return 0; |
| 2261 | } |
| 2262 | |
| 2263 | axp = (void *)ctx->aux_pids; |
| 2264 | if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { |
| 2265 | axp = kzalloc(sizeof(*axp), GFP_ATOMIC); |
| 2266 | if (!axp) |
| 2267 | return -ENOMEM; |
| 2268 | |
| 2269 | axp->d.type = AUDIT_OBJ_PID; |
| 2270 | axp->d.next = ctx->aux_pids; |
| 2271 | ctx->aux_pids = (void *)axp; |
| 2272 | } |
| 2273 | BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); |
| 2274 | |
| 2275 | axp->target_pid[axp->pid_count] = task_tgid_nr(t); |
| 2276 | axp->target_auid[axp->pid_count] = audit_get_loginuid(t); |
| 2277 | axp->target_uid[axp->pid_count] = t_uid; |
| 2278 | axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); |
| 2279 | security_task_getsecid(t, &axp->target_sid[axp->pid_count]); |
| 2280 | memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); |
| 2281 | axp->pid_count++; |
| 2282 | |
| 2283 | return 0; |
| 2284 | } |
| 2285 | |
| 2286 | /** |
| 2287 | * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps |
| 2288 | * @bprm: pointer to the bprm being processed |
| 2289 | * @new: the proposed new credentials |
| 2290 | * @old: the old credentials |
| 2291 | * |
| 2292 | * Simply check if the proc already has the caps given by the file and if not |
| 2293 | * store the priv escalation info for later auditing at the end of the syscall |
| 2294 | * |
| 2295 | * -Eric |
| 2296 | */ |
| 2297 | int __audit_log_bprm_fcaps(struct linux_binprm *bprm, |
| 2298 | const struct cred *new, const struct cred *old) |
| 2299 | { |
| 2300 | struct audit_aux_data_bprm_fcaps *ax; |
| 2301 | struct audit_context *context = current->audit_context; |
| 2302 | struct cpu_vfs_cap_data vcaps; |
| 2303 | |
| 2304 | ax = kmalloc(sizeof(*ax), GFP_KERNEL); |
| 2305 | if (!ax) |
| 2306 | return -ENOMEM; |
| 2307 | |
| 2308 | ax->d.type = AUDIT_BPRM_FCAPS; |
| 2309 | ax->d.next = context->aux; |
| 2310 | context->aux = (void *)ax; |
| 2311 | |
| 2312 | get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps); |
| 2313 | |
| 2314 | ax->fcap.permitted = vcaps.permitted; |
| 2315 | ax->fcap.inheritable = vcaps.inheritable; |
| 2316 | ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE); |
| 2317 | ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT; |
| 2318 | |
| 2319 | ax->old_pcap.permitted = old->cap_permitted; |
| 2320 | ax->old_pcap.inheritable = old->cap_inheritable; |
| 2321 | ax->old_pcap.effective = old->cap_effective; |
| 2322 | |
| 2323 | ax->new_pcap.permitted = new->cap_permitted; |
| 2324 | ax->new_pcap.inheritable = new->cap_inheritable; |
| 2325 | ax->new_pcap.effective = new->cap_effective; |
| 2326 | return 0; |
| 2327 | } |
| 2328 | |
| 2329 | /** |
| 2330 | * __audit_log_capset - store information about the arguments to the capset syscall |
| 2331 | * @new: the new credentials |
| 2332 | * @old: the old (current) credentials |
| 2333 | * |
| 2334 | * Record the arguments userspace sent to sys_capset for later printing by the |
| 2335 | * audit system if applicable |
| 2336 | */ |
| 2337 | void __audit_log_capset(const struct cred *new, const struct cred *old) |
| 2338 | { |
| 2339 | struct audit_context *context = current->audit_context; |
| 2340 | context->capset.pid = task_pid_nr(current); |
| 2341 | context->capset.cap.effective = new->cap_effective; |
| 2342 | context->capset.cap.inheritable = new->cap_effective; |
| 2343 | context->capset.cap.permitted = new->cap_permitted; |
| 2344 | context->type = AUDIT_CAPSET; |
| 2345 | } |
| 2346 | |
| 2347 | void __audit_mmap_fd(int fd, int flags) |
| 2348 | { |
| 2349 | struct audit_context *context = current->audit_context; |
| 2350 | context->mmap.fd = fd; |
| 2351 | context->mmap.flags = flags; |
| 2352 | context->type = AUDIT_MMAP; |
| 2353 | } |
| 2354 | |
| 2355 | static void audit_log_task(struct audit_buffer *ab) |
| 2356 | { |
| 2357 | kuid_t auid, uid; |
| 2358 | kgid_t gid; |
| 2359 | unsigned int sessionid; |
| 2360 | char comm[sizeof(current->comm)]; |
| 2361 | |
| 2362 | auid = audit_get_loginuid(current); |
| 2363 | sessionid = audit_get_sessionid(current); |
| 2364 | current_uid_gid(&uid, &gid); |
| 2365 | |
| 2366 | audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", |
| 2367 | from_kuid(&init_user_ns, auid), |
| 2368 | from_kuid(&init_user_ns, uid), |
| 2369 | from_kgid(&init_user_ns, gid), |
| 2370 | sessionid); |
| 2371 | audit_log_task_context(ab); |
| 2372 | audit_log_format(ab, " pid=%d comm=", task_pid_nr(current)); |
| 2373 | audit_log_untrustedstring(ab, get_task_comm(comm, current)); |
| 2374 | audit_log_d_path_exe(ab, current->mm); |
| 2375 | } |
| 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_task(ab); |
| 2398 | audit_log_format(ab, " sig=%ld", signr); |
| 2399 | audit_log_end(ab); |
| 2400 | } |
| 2401 | |
| 2402 | void __audit_seccomp(unsigned long syscall, long signr, int code) |
| 2403 | { |
| 2404 | struct audit_buffer *ab; |
| 2405 | |
| 2406 | ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_SECCOMP); |
| 2407 | if (unlikely(!ab)) |
| 2408 | return; |
| 2409 | audit_log_task(ab); |
| 2410 | audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x", |
| 2411 | signr, syscall_get_arch(), syscall, is_compat_task(), |
| 2412 | KSTK_EIP(current), code); |
| 2413 | audit_log_end(ab); |
| 2414 | } |
| 2415 | |
| 2416 | struct list_head *audit_killed_trees(void) |
| 2417 | { |
| 2418 | struct audit_context *ctx = current->audit_context; |
| 2419 | if (likely(!ctx || !ctx->in_syscall)) |
| 2420 | return NULL; |
| 2421 | return &ctx->killed_trees; |
| 2422 | } |